Thiswork investigates an oblique stagnation point flowof hybrid nanofluid over a rigid surface with power lawfluidas lubricated layers. Copper (Cu) and Silver (Ag) solid particles are used as hybrid particles acting i...Thiswork investigates an oblique stagnation point flowof hybrid nanofluid over a rigid surface with power lawfluidas lubricated layers. Copper (Cu) and Silver (Ag) solid particles are used as hybrid particles acting in water H2O asa base fluid. The mathematical formulation of flow configuration is presented in terms of differential systemthat isnonlinear in nature. The thermal aspects of the flow field are also investigated by assuming the surface is a heatedsurface with a constant temperature T. Numerical solutions to the governing mathematical model are calculatedby the RK45 algorithm. The results based on the numerical solution against various flow and thermal controllingparameters are presented in terms of line graphs. The specific results depict that the heat flux increases over thelubricated-indexed parameter.展开更多
Objective:To investigate the effect of Guangdong Shenqu(GSQ)on intestinal flora structure in mice with food stagnation through 16S rDNA sequencing.Methods: Mice were randomly assigned to control,model,GSQ low-dose(GSQ...Objective:To investigate the effect of Guangdong Shenqu(GSQ)on intestinal flora structure in mice with food stagnation through 16S rDNA sequencing.Methods: Mice were randomly assigned to control,model,GSQ low-dose(GSQL),GSQ medium-dose(GSQM),GSQ high-dose(GSQH),and lacidophilin tablets(LAB)groups,with each group containing 10 mice.A food stagnation and internal heat mouse model was established through intragastric administration of a mixture of beeswax and olive oil(1:15).The control group was administered normal saline,and the model group was administered beeswax and olive oil to maintain a state.The GSQL(2 g/kg),GSQM(4 g/kg),GSQH(8 g/kg),and LAB groups(0.625 g/kg)were administered corresponding drugs for 5 d.After administration,16S rDNA sequencing was performed to assess gut microbiota in mouse fecal samples.Results: The model group exhibited significant intestinal flora changes.Following GSQ administration,the abundance and diversity index of the intestinal flora increased significantly,the number of bacterial species was regulated,andαandβdiversity were improved.GSQ administration increased the abundance of probiotics,including Clostridia,Lachnospirales,and Lactobacillus,whereas the abundance of conditional pathogenic bacteria,such as Allobaculum,Erysipelotrichaceae,and Bacteroides decreased.Functional prediction analysis indicated that the pathogenesis of food stagnation and GSQ intervention were primarily associated with carbohydrate,lipid,and amino acid metabolism,among other metabolic pathways.Conclusion: The digestive mechanism of GSQ may be attributed to its role in restoring diversity and abundance within the intestinal flora,thereby improving the composition and structure of the intestinal flora in mice and subsequently influencing the regulation of metabolic pathways.展开更多
Hybrid nanofluids are remarkable functioning liquids that are intended to reduce the energy loss while maximizing the heat transmission.In the involvement of suction and nonlinear thermal radiation effects,this study ...Hybrid nanofluids are remarkable functioning liquids that are intended to reduce the energy loss while maximizing the heat transmission.In the involvement of suction and nonlinear thermal radiation effects,this study attempted to explore the energy transmission features of the inclined magnetohydrodynamic(MHD)stagnation flow of CNTs-hybrid nanofluid across the nonlinear permeable stretching or shrinking sheet.This work also included some noteworthy features like chemical reactions,variable molecular diffusivity,quadratic convection,viscous dissipation,velocity slip and heat omission assessment.Employing appropriate similarity components,the model equations were modified to ODEs and computed by using the HAM technique.The impact of various relevant flow characteristics on movement,heat and concentration profiles was investigated and plotted on a graph.Considering various model factors,the significance of drag friction,heat and mass transfer rate were also computed in tabular and graphical form.This leads to the conclusion that such factors have a considerable impact on the dynamics of fluid as well as other engineering measurements of interest.Furthermore,viscous forces are dominated by increasing the values ofλ_(p),δ_(m)andδ_(q),and as a result,F(ξ)accelerates while the opposite trend is observed for M andφ.The drag friction is boosted by the augmentation M,λ_(p)andφ,but the rate of heat transfer declined.According to our findings,hybrid nanoliquid effects dominate that of ordinary nanofluid in terms of F(ξ),Θ(ξ)andφ(ξ)profiles.The HAM and the numerical technique(shooting method)were found to be in good agreement.展开更多
Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network...Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network pharmacology.Methods Patients with gastroesophageal reflux disease(GERD)of liver–stomach stagnant heat pattern who met the inclusion and exclusion criteria were randomly divided into the control group and the observation group.The control group received oral rabeprazole,whereas the observation group were given Zhenzhu Qingyuan Granules in addition to the rabeprazole.The treatment duration was 8 weeks.Clinical efficacy was observed in both groups after 8 weeks.Network pharmacology was used to analyze the action targets of ZhenzhuQingyuanGranules and the genes related to GERD,and core targets were inferred.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential mechanisms of this formula.Results The clinical research results showed that the total effective rate in the treatment group was 92.68%,compared with 70.00%in the control group,with a statistically significant difference(p<0.05).After treatment,both Chinese medicine syndrome score and endoscopic score improved in both groups compared with before treatment(p<0.05),and the treatment group showed greater improvement than the control group(p<0.05).Network pharmacology identified effective components of Zhenzhu Qingyuan Granules for treating GERD,including quercetin,luteolin,andβ-sitosterol,with potential action targets such as tumor protein 53(TP53),protein kinase B(AKT1),and tumor necrosis factor.Conclusion Zhenzhu Qingyuan Granules can significantly improve clinical symptoms in patients with GERD of liver–stomach stagnated heat pattern,enhance clinical efficacy,and have high safety.This formula may exert therapeutic effects through multiple targets and pathways.展开更多
This paper proposes a mathematical modeling approach to examine the two-dimensional flow stagnates at x=0 over a heated stretchable sheet in a porous medium influenced by nonlinear thermal radiation,variable viscosity...This paper proposes a mathematical modeling approach to examine the two-dimensional flow stagnates at x=0 over a heated stretchable sheet in a porous medium influenced by nonlinear thermal radiation,variable viscosity,and MHD.This study’s main purpose is to examine how thermal radiation and varying viscosity affect fluid flow motion.Additionally,we consider the convective boundary conditions and incorporate the gyrotactic microorganisms equation,which describes microorganism behavior in response to fluid flow.The partial differential equations(PDEs)that represent the conservation equations for mass,momentum,energy,and microorganisms are then converted into a system of coupled ordinary differential equations(ODEs)through the inclusion of nonsimilarity variables.Using MATLAB’s built-in solver bvp4c,the resulting ODEs are numerically solved.The model’s complexity is assessed by plotting two-dimensional graphics of the solution profiles at various physical parameter values.The physical parameters considered in this study include skin friction coefficient,local Nusselt number,local Sherwood number,and density of motile microorganisms.These parameters measure,respectively,the roughness of the sheet,the transformation rate of heat,the rate at which mass is transferred to it,and the rate at which microorganisms are transferred to it.Our study shows that,depending on the magnetic parameter M,the presence of a porous medium causes a significant increase in fluid velocity,ranging from about 25%to 45%.Furthermore,with an increase in the Prandtl number Pr,we have seen a notable improvement of about 6%in fluid thermal conductivity.Additionally,our latest findings are in good agreement with published research for particular values.This study provides valuable insights into the behavior of fluid flow under various physical conditions and can be useful in designing and optimizing industrial processes.展开更多
Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis,...Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH.展开更多
Gastroesophageal reflux disease (GERD) is a high-incidence digestive system disease. Western medicine mainly uses drugs such as proton pump inhibitors to inhibit gastric acid secretion, but some patients are accompani...Gastroesophageal reflux disease (GERD) is a high-incidence digestive system disease. Western medicine mainly uses drugs such as proton pump inhibitors to inhibit gastric acid secretion, but some patients are accompanied by symptoms such as non-acid reflux and gas reflux, which cannot effectively treat the disease. It is necessary to actively explore other treatment schemes. Traditional Chinese medicine (TCM) has a long history of research on gastroesophageal reflux disease, which emphasizes the treatment based on syndrome differentiation as a whole. Through the treatment of various and multi-component TCM prescriptions, the patient’s body condition can be adjusted, and the treatment effect on gastroesophageal reflux disease is reliable, which has obvious therapeutic advantages. To further clarify the treatment of gastroesophageal reflux disease, this study reviewed and analyzed the research progress of the treatment of liver disease with modified prescriptions, and the report is as follows.展开更多
In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer...In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer phenomenon is involved.Fourier’s law of heat conduction has been used as the foundation for predicting the heat transfer behavior in a variety of real-world contexts.This model’s production of a parabolic energy expression,which means that an initial disturbance would immediately affect the system under investigation,is one of its main drawbacks.Therefore,numerous researchers worked on such problem to resolve this issue.At last,this problem was resolved by Cattaneo by adding relaxation time for heat flux in Fourier’s law,which was defined as the time required to establish steady heat conduction once a temperature gradient is imposed.Christov offered a material invariant version of Cattaneo’s model by taking into account the upper-connected derivative of the Oldroyd model.Nowadays,both models are combinedly known as the Cattaneo-Christov(CC)model.In this attempt,the mixed convective MHD Falkner-Skan Sutterby nanofluid flow is addressed towards a wedge surface in the presence of the variable external magnetic field.The CC model is incorporated instead of Fourier’s law for the examination of heat transfer features in the energy expression.A two-phase nanofluid model is utilized for the implementation of nano-concept.The nonlinear system of equations is tackled through the bvp4c technique in the MATLAB software 2016.The influence of pertinent flow parameters is discussed and displayed through different sketches.Major and important results are summarized in the conclusion section.Furthermore,in both cases of wall-through flow(i.e.,suction and injection effects),the porosity parameters increase the flow speed,and decrease the heat transport and the influence of drag forces.展开更多
In this paper,the effects of thermal radiation and viscous dissipation on the stagnation–point flow of a micropolar fluid over a permeable stretching sheet with suction and injection are analyzed and discussed.A suit...In this paper,the effects of thermal radiation and viscous dissipation on the stagnation–point flow of a micropolar fluid over a permeable stretching sheet with suction and injection are analyzed and discussed.A suitable similarity transformation is used to convert the governing nonlinear partial differential equations into a system of nonlinear ordinary differential equations,which are then solved numerically by a fourth–order Runge–Kutta method.It is found that the linear fluid velocity decreases with the enhancement of the porosity,boundary,and suction parameters.Conversely,it increases with the micropolar and injection parameters.The angular velocity grows with the boundary,porosity,and suction parameters,whereas it is reduced if the micropolar and injection parameters become larger.It is concluded that the thermal boundary layer extension increases with the injection parameter and decreases with the suction parameter.展开更多
This study investigates the suction and magnetic field effects on the two-dimensional nanofluid flow through a stretching/shrinking sheet at the stagnation point in the porous medium with thermal radiation.The governi...This study investigates the suction and magnetic field effects on the two-dimensional nanofluid flow through a stretching/shrinking sheet at the stagnation point in the porous medium with thermal radiation.The governing partial differential equations(PDEs)are converted into ordinary differential equations(ODEs)using the similarity transformation.The resulting ODEs are then solved numerically by using the bvp4c solver in MATLAB software.It was found that dual solutions exist for the shrinking parameter values up to a certain range.The numerical results obtained are compared,and the comparison showed a good agreement with the existing results in the literature.The governing parameters’effect on the velocity,temperature and nanoparticle fraction fields as well as the skin friction coefficient,the local Nusselt number and the Sherwood number are represented graphically and analyzed.The variation of the velocity,temperature and concentration increase with the increase in the suction and magnetic field parameters.It seems that the thermal radiation effect has increased the local Sherwood number while the local Nusselt number is reduced with it.展开更多
Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has develop...Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.展开更多
This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity slips.To the authors’knowledge,this is...This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity slips.To the authors’knowledge,this is the first study presenting this very interesting analysis.Nonlinear partial differential equations for the flow problem are transformed into nonlinear ordinary differential equations(ODEs)by using appropriate similarity transformation.These ODEs with the corresponding boundary conditions are numerically solved by utilizing the bvp4c solver in MATLAB programming language.The effects of the governing parameters on the non-dimensional velocity profiles,temperature profiles,skin friction coefficients,and the local Nusselt number are presented in detail through a series of graphs and tables.Interestingly,it is reported that the reduced skin friction coefficient decreases for the assisting flow situation and increases for the opposing flow situation.The numerical computations of the present work are compared with those from other research available in specific situations,and an excellent consensus is observed.Another exciting feature for this work is the existence of dual solutions.An important remark is that the dual solutions exist for both assisting and opposing flows.A linear stability analysis is performed showing that one solution is stable and the other solution is not stable.We notice that the mixed convection and velocity slip parameters have strong effects on the flow characteristics.These effects are depicted in graphs and discussed in this paper.The obtained results show that the first-order and second-order slip parameters have a considerable effect on the flow,as well as on the heat transfer characteristics.展开更多
Objective: To evaluate the curative effect of the Traditional Chinese Medicine (TCM) external therapy on knee osteoarthritis patients with different TCM constitutions using musculoskeletal ultrasonography and contrast...Objective: To evaluate the curative effect of the Traditional Chinese Medicine (TCM) external therapy on knee osteoarthritis patients with different TCM constitutions using musculoskeletal ultrasonography and contrast-enhanced ultrasonography, and to explore the application value of contrast-enhanced ultrasonography in knee joint diseases. Methods: A total of 57 patients diagnosed with knee osteoarthritis in Shaanxi University of Traditional Chinese Medicine from December 2019 to May 2021 were collected, and they were divided into qi stagnation and blood stasis type group (23 cases) and cold-dampness obstruction type group (34 cases) according to the traditional Chinese medicine method. All patients were given acupuncture combined with TCM fumigation and washing. All patients underwent musculoskeletal ultrasonography and contrast-enhanced ultrasonography before and after treatment, observed and recorded relevant data, and compared the treatment effects between the two groups. Results: 85.96% (49/57) of knee osteoarthritis (KOA) patients had suprapatellar bursa effusion, 42.1% (24/57) had iliotibial band bursae effusion, some of which had poor sound transmission, and thickened synovium was seen in most effusions, 33.33% (19/57) had osteophyte formation. Compared with before treatment, the depth of suprapatellar sac effusion in the Qi stagnation and blood stasis type group decreased after treatment (P Conclusion: Musculoskeletal contrast-enhanced ultrasonography was used to quantitatively evaluate the efficacy of TCM external therapy on KOA for different TCM constitutions. Dynamic observation of synovial lesions of knee osteoarthritis provides a valuable imaging method for evaluating the efficacy of traditional Chinese medicine.展开更多
In this particular study,we have considered the flow of Casson fluid over inclined flat and cylindrical surfaces,and have conducted a numerical analysis taking into account various physical factors such as mixed conve...In this particular study,we have considered the flow of Casson fluid over inclined flat and cylindrical surfaces,and have conducted a numerical analysis taking into account various physical factors such as mixed convection,stagnation point flow,MHD,thermal radiation,viscous dissipation,heat generation,Joule heating effect,variable thermal conductivity and chemical reaction.Flow over flat plate phenomena is observed aerospace industry,and airflow over solar panels,etc.Cylindrical surfaces are commonly used in several applications interacting with fluids,such as bridges,cables,and buildings,so the study of fluid flow over cylindrical surfaces is more important.Due to the motivation of these applications,in this paper,a comparative study of fluid flow over these two surfaces is considered.By applying appropriate similarity transformations,the governing PDEs of the problem have been transformed into non-linear ODEs,which are solved by utilizing the Keller box technique.We have examined the impact of distinct parameters by plotting velocity and thermal concentration graphs.All the profiles are plotted in both cases of cylindrical and inclined flat surface.It has been observed that for higher Casson and Magnetic parameter values,a decreasing velocity profile is noted for progressive values of the Eckert Number,thermal conductivity parameter,Joule heating parameter,heat generation,and growth in temperature profiles are witnessed.While the Prandtl number shows the opposite trend.Further,it has been observed that the concentration profile declines for incremental observations of Schmidt number and chemical reaction parameters.Computed Local parameters like the coefficient of skin friction for various values of Casson parameter and Curvature parameter,Skin friction value increases for increasing observations of Curvature parameter the phenomena agree with existing literature.Also,Nusselt number is calculated for various observations of curvature and variable thermal conductivity parameters.Nusselt number decreases in magnitude with rising observations of varying thermal conductivity argument at both flat and cylindrical surfaces.The values are matched with prevailing results and noted a good agreement.展开更多
The theory of stagnation of collateral Qi(Chinese medicine refers to the most fundamental and subtle substances thatconstitute the human body and maintain life activities,and also has the meaning of physiological func...The theory of stagnation of collateral Qi(Chinese medicine refers to the most fundamental and subtle substances thatconstitute the human body and maintain life activities,and also has the meaning of physiological functions)originates from the theory of collateral disease,which refers to the deficiency of Qi in the body’s collaterals,the loss of Qi and blood,and the failure of stagnation of collateral Qi,which leads to the loss of Qi,blood and body fluid,and the formation of pathological products such as deficiency,depression,phlegm,blood stasis in the local area,and ultimately damage the pathological process of collaterals.Based on the in-depth study of the pathogenesis of collateral Qi stagnation and the previous study of meridian channels,we believe that the key pathogenesis of the formation,evolution and spread of malignant tumors is“collateral Qi deficiency stagnation,collateral Qi stagnation and collateral Qi decay”.As an important energy resonance channel of the body,meridians play a key role in the process of material transformation and energy metabolism.It is believed that the small focus caused by the pathogenesis of stagnation is the cause of malignant transformation of tumor,the reprogramming of energy metabolism induced by the lesion of collateral Qi is the basis of the progress of tumor pathogenesis,and the formation of tumor microenvironment regulated by the tumor toxin vena is the root of alienation of tumor development.Guided by this theory,focusing on the correlation between collateral Qi and tumor energy metabolism,using Professor Hua Baojin's treatment method of“Regulating Qi and detoxifying”to prescribe drugs can adjust collateral Qi function,achieve the relative balance of internal environment,and then inhibit the progress of tumor.Based on the above understanding,this study tries to enlighten new diagnosis and treatment ideas under the guidance of“stagnation of collateral Qi”in traditional Chinese medicine,in order to provide some theoretical support for the intervention of traditional Chinese medicine in the process of tumor development.展开更多
Introduction:Functional Constipation(FC)is a type of functional bowel disease that is in Clinically characterized by dysportia,decreased frequency of bowel movements,or incomplete bowel movements in the absence of irr...Introduction:Functional Constipation(FC)is a type of functional bowel disease that is in Clinically characterized by dysportia,decreased frequency of bowel movements,or incomplete bowel movements in the absence of irritable bowel syndrome syndrome,at least 6 months before diagnosis,and symptoms within the last 3 months.At present,commonly used drugs include enema and suppositories,laxatives,microecological preparations,gastrointestinal motility drugs and other treatments.However,the effect is limited.Traditional Chinese medicine(TCM)treatment of FC has advantages.Methods:In this randomized controlled study,244 eligible patients were randomly assigned in a 1:1 ratio to a treatment group(Zangfu ointment and massage therapy+Lactulose Oral Liquid)and a control group(Lactulose Oral Liquid)for 14 days.Number of spontaneous defecation per week and First defecation time will be used as primary outcomes,and Traditional Chinese Medicine(TCM)syndrome scores and syndrome scores,PAC-QOL form will be used as secondary outcomes.Blood routine,liver function,and renal function will be used as safety outcomes.The primary and secondary outcomes will be performed at 0th,7th,and 14th day,and the safety outcomes will be performed at 0th and 14th day.Ethics and dissemination:Ethical approval has been obtained from the Committee on Health Research Ethics of the Fangshan Hospital,Beijing University of Chinese Medicine,Beijing,People's Republic of China(FZY LK-2020-010)on September 18,2020.All patients will be provided oral and written information about the trial before screening.The study results will be disseminated by peer-review publications and conference presentations.Trial registration number:ChiCTR2000038754(registered on April 14,2021).This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial license,which permits others to distribute,remix,adapt,build upon this work non-commercially,and license their derivative works on different terms,provided the original work is properly cited,appropriate credit is given,any changes made indicated,and the use is non-commercial.STRENGTHS AND LIMITATIONS OF THIS STUDY(1)The efficacy of the Zangfu ointment and massage therapy is evaluated in a randomised,double-blind 2-week clinical trial in FC patients.(2)Form a complete and generalizable regimen for the treatment of FC(Qi stagnation)with the Zangfu ointment and massage therapy.展开更多
The double flapper-nozzle servo valve is widely used to launch and guide the equipment. Due to the large instantaneous flow rate of servo valve working under specific operating conditions, the temperature of servo val...The double flapper-nozzle servo valve is widely used to launch and guide the equipment. Due to the large instantaneous flow rate of servo valve working under specific operating conditions, the temperature of servo valve would reach 120℃ and the valve core and valve sleeve deform in a short amount of time. So the control precision of servo valve significantly decreases and the clamping stagnation phenomenon of valve core appears. In order to solve the problem of degraded control accuracy and clamping stagnation of servo valve under large temperature difference circumstance, the numerical simulation of heat-fluid-solid coupling by using finite element method is done. The simulation result shows that zero position leakage of servo valve is basically impacted by oil temperature and change of fit clearance. The clamping stagnation is caused by warpage-deformation and fit clearance reduction of the valve core and valve sleeve. The distribution roles of the temperature and thermal-deformation of shell, valve core and valve sleeve and the pressure, velocity and temperature field of flow channel are also analyzed. Zero position leakage and electromagnet's current when valve core moves in full-stroke are tested using Electro-hydraulic Servo-valve Characteristic Test-bed of an aerospace sciences and technology corporation. The experimental results show that the change law of experimental current at different oil temperatures is roughly identical to simulation current. The current curve of the electromagnet is smooth when oil temperature is below 80℃, but the amplitude of current significantly increases and the hairy appears when oil temperature is above 80℃. The current becomes smooth again after the warped valve core and valve sleeve are reground. It indicates that clamping stagnation is caused by warpage-deformation and fit clearance reduction of valve core and valve sleeve. This paper simulates and tests the heat-fluid-solid coupling of double flapper-nozzle servo valve, and the obtained results provide the reference value for the design of double flapper-nozzle force feedback servo valve.展开更多
When perforating with an abrasive water jet, it is possible that the pressure in the hole (perforation) will be higher than that in the annulus because of water jet blasting against the hole wall, which also is the ...When perforating with an abrasive water jet, it is possible that the pressure in the hole (perforation) will be higher than that in the annulus because of water jet blasting against the hole wall, which also is the theoretical basis for the technology of hydro-jet fracturing. This paper analyzes the mechanism of generating pressure stagnation in water jet hole, and puts forward a new concept of hydroseal. Then, the distribution of pressure in the hole was simulated with the finite element method. The simulation results showed that the pressure in the hole was higher than that in the annulus. Also, the lower the annular pressure (confining pressure) and the higher the blasting pressure, the greater the pressure difference. An experiment indicated that the cement sample was lifted up under the pressure stagnation in the hole, which proved the finite element simulation results obviously.展开更多
In this paper a mathematical model is built for a buried hot crude oil pipeline during shutdown, and an unstructured grid and polar coordinate grid are respectively applied to generating grids for the soil region and ...In this paper a mathematical model is built for a buried hot crude oil pipeline during shutdown, and an unstructured grid and polar coordinate grid are respectively applied to generating grids for the soil region and the three layers in the pipe (wax layer, pipe wall, and corrosion-inhibiting coating). The governing equations are discretized using the finite volume method. The variations in temperatures of static oil and soil were investigated during pipeline shutdown in both summer and winter, in which some important parameters of the soil and crude oils of a Northeast pipeline are employed.展开更多
文摘Thiswork investigates an oblique stagnation point flowof hybrid nanofluid over a rigid surface with power lawfluidas lubricated layers. Copper (Cu) and Silver (Ag) solid particles are used as hybrid particles acting in water H2O asa base fluid. The mathematical formulation of flow configuration is presented in terms of differential systemthat isnonlinear in nature. The thermal aspects of the flow field are also investigated by assuming the surface is a heatedsurface with a constant temperature T. Numerical solutions to the governing mathematical model are calculatedby the RK45 algorithm. The results based on the numerical solution against various flow and thermal controllingparameters are presented in terms of line graphs. The specific results depict that the heat flux increases over thelubricated-indexed parameter.
基金supported by the National Natural Science Foundation of China(81872995).
文摘Objective:To investigate the effect of Guangdong Shenqu(GSQ)on intestinal flora structure in mice with food stagnation through 16S rDNA sequencing.Methods: Mice were randomly assigned to control,model,GSQ low-dose(GSQL),GSQ medium-dose(GSQM),GSQ high-dose(GSQH),and lacidophilin tablets(LAB)groups,with each group containing 10 mice.A food stagnation and internal heat mouse model was established through intragastric administration of a mixture of beeswax and olive oil(1:15).The control group was administered normal saline,and the model group was administered beeswax and olive oil to maintain a state.The GSQL(2 g/kg),GSQM(4 g/kg),GSQH(8 g/kg),and LAB groups(0.625 g/kg)were administered corresponding drugs for 5 d.After administration,16S rDNA sequencing was performed to assess gut microbiota in mouse fecal samples.Results: The model group exhibited significant intestinal flora changes.Following GSQ administration,the abundance and diversity index of the intestinal flora increased significantly,the number of bacterial species was regulated,andαandβdiversity were improved.GSQ administration increased the abundance of probiotics,including Clostridia,Lachnospirales,and Lactobacillus,whereas the abundance of conditional pathogenic bacteria,such as Allobaculum,Erysipelotrichaceae,and Bacteroides decreased.Functional prediction analysis indicated that the pathogenesis of food stagnation and GSQ intervention were primarily associated with carbohydrate,lipid,and amino acid metabolism,among other metabolic pathways.Conclusion: The digestive mechanism of GSQ may be attributed to its role in restoring diversity and abundance within the intestinal flora,thereby improving the composition and structure of the intestinal flora in mice and subsequently influencing the regulation of metabolic pathways.
基金funded by King Mongkut’s University of Technology North Bangkok with Contract no.KMUTNB-Post-65-07。
文摘Hybrid nanofluids are remarkable functioning liquids that are intended to reduce the energy loss while maximizing the heat transmission.In the involvement of suction and nonlinear thermal radiation effects,this study attempted to explore the energy transmission features of the inclined magnetohydrodynamic(MHD)stagnation flow of CNTs-hybrid nanofluid across the nonlinear permeable stretching or shrinking sheet.This work also included some noteworthy features like chemical reactions,variable molecular diffusivity,quadratic convection,viscous dissipation,velocity slip and heat omission assessment.Employing appropriate similarity components,the model equations were modified to ODEs and computed by using the HAM technique.The impact of various relevant flow characteristics on movement,heat and concentration profiles was investigated and plotted on a graph.Considering various model factors,the significance of drag friction,heat and mass transfer rate were also computed in tabular and graphical form.This leads to the conclusion that such factors have a considerable impact on the dynamics of fluid as well as other engineering measurements of interest.Furthermore,viscous forces are dominated by increasing the values ofλ_(p),δ_(m)andδ_(q),and as a result,F(ξ)accelerates while the opposite trend is observed for M andφ.The drag friction is boosted by the augmentation M,λ_(p)andφ,but the rate of heat transfer declined.According to our findings,hybrid nanoliquid effects dominate that of ordinary nanofluid in terms of F(ξ),Θ(ξ)andφ(ξ)profiles.The HAM and the numerical technique(shooting method)were found to be in good agreement.
基金National Administration of Traditional Chinese Medicine Evidence-Based Capacity Building Project(2019XZZXXH005)Special Project on Traditional Chinese Medicine Scientific Research of Health Commission of Henan Province(2022ZY2022)+1 种基金Henan Provincial Top Talents Cultivation Project in Traditional Chinese Medicine Discipline of Henan Provincial Traditional Chinese Medicine Inheritance and Innovation Talents Project(Zhongjing Project)(Henan Health TraditionalMedicine Letter[2021]No.15)Special Project on Traditional Chinese Medicine Scientific Research of Health Commission of Henan Province(2023ZY2062).
文摘Objective To evaluate the clinical efficacy and safety of Zhenzhu Qingyuan Granules through a clinical randomized controlled trial and to analyze the potential action targets and pathways of this formula using network pharmacology.Methods Patients with gastroesophageal reflux disease(GERD)of liver–stomach stagnant heat pattern who met the inclusion and exclusion criteria were randomly divided into the control group and the observation group.The control group received oral rabeprazole,whereas the observation group were given Zhenzhu Qingyuan Granules in addition to the rabeprazole.The treatment duration was 8 weeks.Clinical efficacy was observed in both groups after 8 weeks.Network pharmacology was used to analyze the action targets of ZhenzhuQingyuanGranules and the genes related to GERD,and core targets were inferred.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted to explore the potential mechanisms of this formula.Results The clinical research results showed that the total effective rate in the treatment group was 92.68%,compared with 70.00%in the control group,with a statistically significant difference(p<0.05).After treatment,both Chinese medicine syndrome score and endoscopic score improved in both groups compared with before treatment(p<0.05),and the treatment group showed greater improvement than the control group(p<0.05).Network pharmacology identified effective components of Zhenzhu Qingyuan Granules for treating GERD,including quercetin,luteolin,andβ-sitosterol,with potential action targets such as tumor protein 53(TP53),protein kinase B(AKT1),and tumor necrosis factor.Conclusion Zhenzhu Qingyuan Granules can significantly improve clinical symptoms in patients with GERD of liver–stomach stagnated heat pattern,enhance clinical efficacy,and have high safety.This formula may exert therapeutic effects through multiple targets and pathways.
文摘This paper proposes a mathematical modeling approach to examine the two-dimensional flow stagnates at x=0 over a heated stretchable sheet in a porous medium influenced by nonlinear thermal radiation,variable viscosity,and MHD.This study’s main purpose is to examine how thermal radiation and varying viscosity affect fluid flow motion.Additionally,we consider the convective boundary conditions and incorporate the gyrotactic microorganisms equation,which describes microorganism behavior in response to fluid flow.The partial differential equations(PDEs)that represent the conservation equations for mass,momentum,energy,and microorganisms are then converted into a system of coupled ordinary differential equations(ODEs)through the inclusion of nonsimilarity variables.Using MATLAB’s built-in solver bvp4c,the resulting ODEs are numerically solved.The model’s complexity is assessed by plotting two-dimensional graphics of the solution profiles at various physical parameter values.The physical parameters considered in this study include skin friction coefficient,local Nusselt number,local Sherwood number,and density of motile microorganisms.These parameters measure,respectively,the roughness of the sheet,the transformation rate of heat,the rate at which mass is transferred to it,and the rate at which microorganisms are transferred to it.Our study shows that,depending on the magnetic parameter M,the presence of a porous medium causes a significant increase in fluid velocity,ranging from about 25%to 45%.Furthermore,with an increase in the Prandtl number Pr,we have seen a notable improvement of about 6%in fluid thermal conductivity.Additionally,our latest findings are in good agreement with published research for particular values.This study provides valuable insights into the behavior of fluid flow under various physical conditions and can be useful in designing and optimizing industrial processes.
文摘Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH.
文摘Gastroesophageal reflux disease (GERD) is a high-incidence digestive system disease. Western medicine mainly uses drugs such as proton pump inhibitors to inhibit gastric acid secretion, but some patients are accompanied by symptoms such as non-acid reflux and gas reflux, which cannot effectively treat the disease. It is necessary to actively explore other treatment schemes. Traditional Chinese medicine (TCM) has a long history of research on gastroesophageal reflux disease, which emphasizes the treatment based on syndrome differentiation as a whole. Through the treatment of various and multi-component TCM prescriptions, the patient’s body condition can be adjusted, and the treatment effect on gastroesophageal reflux disease is reliable, which has obvious therapeutic advantages. To further clarify the treatment of gastroesophageal reflux disease, this study reviewed and analyzed the research progress of the treatment of liver disease with modified prescriptions, and the report is as follows.
基金Deanship of Scientific Research at King Khalid University for funding this work through Large Group Research Project(No.RGP2/19/44)。
文摘In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer phenomenon is involved.Fourier’s law of heat conduction has been used as the foundation for predicting the heat transfer behavior in a variety of real-world contexts.This model’s production of a parabolic energy expression,which means that an initial disturbance would immediately affect the system under investigation,is one of its main drawbacks.Therefore,numerous researchers worked on such problem to resolve this issue.At last,this problem was resolved by Cattaneo by adding relaxation time for heat flux in Fourier’s law,which was defined as the time required to establish steady heat conduction once a temperature gradient is imposed.Christov offered a material invariant version of Cattaneo’s model by taking into account the upper-connected derivative of the Oldroyd model.Nowadays,both models are combinedly known as the Cattaneo-Christov(CC)model.In this attempt,the mixed convective MHD Falkner-Skan Sutterby nanofluid flow is addressed towards a wedge surface in the presence of the variable external magnetic field.The CC model is incorporated instead of Fourier’s law for the examination of heat transfer features in the energy expression.A two-phase nanofluid model is utilized for the implementation of nano-concept.The nonlinear system of equations is tackled through the bvp4c technique in the MATLAB software 2016.The influence of pertinent flow parameters is discussed and displayed through different sketches.Major and important results are summarized in the conclusion section.Furthermore,in both cases of wall-through flow(i.e.,suction and injection effects),the porosity parameters increase the flow speed,and decrease the heat transport and the influence of drag forces.
文摘In this paper,the effects of thermal radiation and viscous dissipation on the stagnation–point flow of a micropolar fluid over a permeable stretching sheet with suction and injection are analyzed and discussed.A suitable similarity transformation is used to convert the governing nonlinear partial differential equations into a system of nonlinear ordinary differential equations,which are then solved numerically by a fourth–order Runge–Kutta method.It is found that the linear fluid velocity decreases with the enhancement of the porosity,boundary,and suction parameters.Conversely,it increases with the micropolar and injection parameters.The angular velocity grows with the boundary,porosity,and suction parameters,whereas it is reduced if the micropolar and injection parameters become larger.It is concluded that the thermal boundary layer extension increases with the injection parameter and decreases with the suction parameter.
基金the Fundamental Research Grant Scheme(FRGS)under a grant number of FRGS/1/2018/STG06/UNIMAP/02/3 from the Ministry of Education Malaysia。
文摘This study investigates the suction and magnetic field effects on the two-dimensional nanofluid flow through a stretching/shrinking sheet at the stagnation point in the porous medium with thermal radiation.The governing partial differential equations(PDEs)are converted into ordinary differential equations(ODEs)using the similarity transformation.The resulting ODEs are then solved numerically by using the bvp4c solver in MATLAB software.It was found that dual solutions exist for the shrinking parameter values up to a certain range.The numerical results obtained are compared,and the comparison showed a good agreement with the existing results in the literature.The governing parameters’effect on the velocity,temperature and nanoparticle fraction fields as well as the skin friction coefficient,the local Nusselt number and the Sherwood number are represented graphically and analyzed.The variation of the velocity,temperature and concentration increase with the increase in the suction and magnetic field parameters.It seems that the thermal radiation effect has increased the local Sherwood number while the local Nusselt number is reduced with it.
文摘Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.
基金Project supported by the Executive Agency for Higher Education Research Development and Innovation Funding of Romania(No.PN-III-P4-PCE-2021-0993)。
文摘This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity slips.To the authors’knowledge,this is the first study presenting this very interesting analysis.Nonlinear partial differential equations for the flow problem are transformed into nonlinear ordinary differential equations(ODEs)by using appropriate similarity transformation.These ODEs with the corresponding boundary conditions are numerically solved by utilizing the bvp4c solver in MATLAB programming language.The effects of the governing parameters on the non-dimensional velocity profiles,temperature profiles,skin friction coefficients,and the local Nusselt number are presented in detail through a series of graphs and tables.Interestingly,it is reported that the reduced skin friction coefficient decreases for the assisting flow situation and increases for the opposing flow situation.The numerical computations of the present work are compared with those from other research available in specific situations,and an excellent consensus is observed.Another exciting feature for this work is the existence of dual solutions.An important remark is that the dual solutions exist for both assisting and opposing flows.A linear stability analysis is performed showing that one solution is stable and the other solution is not stable.We notice that the mixed convection and velocity slip parameters have strong effects on the flow characteristics.These effects are depicted in graphs and discussed in this paper.The obtained results show that the first-order and second-order slip parameters have a considerable effect on the flow,as well as on the heat transfer characteristics.
文摘Objective: To evaluate the curative effect of the Traditional Chinese Medicine (TCM) external therapy on knee osteoarthritis patients with different TCM constitutions using musculoskeletal ultrasonography and contrast-enhanced ultrasonography, and to explore the application value of contrast-enhanced ultrasonography in knee joint diseases. Methods: A total of 57 patients diagnosed with knee osteoarthritis in Shaanxi University of Traditional Chinese Medicine from December 2019 to May 2021 were collected, and they were divided into qi stagnation and blood stasis type group (23 cases) and cold-dampness obstruction type group (34 cases) according to the traditional Chinese medicine method. All patients were given acupuncture combined with TCM fumigation and washing. All patients underwent musculoskeletal ultrasonography and contrast-enhanced ultrasonography before and after treatment, observed and recorded relevant data, and compared the treatment effects between the two groups. Results: 85.96% (49/57) of knee osteoarthritis (KOA) patients had suprapatellar bursa effusion, 42.1% (24/57) had iliotibial band bursae effusion, some of which had poor sound transmission, and thickened synovium was seen in most effusions, 33.33% (19/57) had osteophyte formation. Compared with before treatment, the depth of suprapatellar sac effusion in the Qi stagnation and blood stasis type group decreased after treatment (P Conclusion: Musculoskeletal contrast-enhanced ultrasonography was used to quantitatively evaluate the efficacy of TCM external therapy on KOA for different TCM constitutions. Dynamic observation of synovial lesions of knee osteoarthritis provides a valuable imaging method for evaluating the efficacy of traditional Chinese medicine.
文摘In this particular study,we have considered the flow of Casson fluid over inclined flat and cylindrical surfaces,and have conducted a numerical analysis taking into account various physical factors such as mixed convection,stagnation point flow,MHD,thermal radiation,viscous dissipation,heat generation,Joule heating effect,variable thermal conductivity and chemical reaction.Flow over flat plate phenomena is observed aerospace industry,and airflow over solar panels,etc.Cylindrical surfaces are commonly used in several applications interacting with fluids,such as bridges,cables,and buildings,so the study of fluid flow over cylindrical surfaces is more important.Due to the motivation of these applications,in this paper,a comparative study of fluid flow over these two surfaces is considered.By applying appropriate similarity transformations,the governing PDEs of the problem have been transformed into non-linear ODEs,which are solved by utilizing the Keller box technique.We have examined the impact of distinct parameters by plotting velocity and thermal concentration graphs.All the profiles are plotted in both cases of cylindrical and inclined flat surface.It has been observed that for higher Casson and Magnetic parameter values,a decreasing velocity profile is noted for progressive values of the Eckert Number,thermal conductivity parameter,Joule heating parameter,heat generation,and growth in temperature profiles are witnessed.While the Prandtl number shows the opposite trend.Further,it has been observed that the concentration profile declines for incremental observations of Schmidt number and chemical reaction parameters.Computed Local parameters like the coefficient of skin friction for various values of Casson parameter and Curvature parameter,Skin friction value increases for increasing observations of Curvature parameter the phenomena agree with existing literature.Also,Nusselt number is calculated for various observations of curvature and variable thermal conductivity parameters.Nusselt number decreases in magnitude with rising observations of varying thermal conductivity argument at both flat and cylindrical surfaces.The values are matched with prevailing results and noted a good agreement.
基金supported by Beijing Natural Science Foundation(No.7222296)Major research project of oncology of scientific and technological innovation project of China Academy of Chinese Medical Sciences(No.CI2021A01805).
文摘The theory of stagnation of collateral Qi(Chinese medicine refers to the most fundamental and subtle substances thatconstitute the human body and maintain life activities,and also has the meaning of physiological functions)originates from the theory of collateral disease,which refers to the deficiency of Qi in the body’s collaterals,the loss of Qi and blood,and the failure of stagnation of collateral Qi,which leads to the loss of Qi,blood and body fluid,and the formation of pathological products such as deficiency,depression,phlegm,blood stasis in the local area,and ultimately damage the pathological process of collaterals.Based on the in-depth study of the pathogenesis of collateral Qi stagnation and the previous study of meridian channels,we believe that the key pathogenesis of the formation,evolution and spread of malignant tumors is“collateral Qi deficiency stagnation,collateral Qi stagnation and collateral Qi decay”.As an important energy resonance channel of the body,meridians play a key role in the process of material transformation and energy metabolism.It is believed that the small focus caused by the pathogenesis of stagnation is the cause of malignant transformation of tumor,the reprogramming of energy metabolism induced by the lesion of collateral Qi is the basis of the progress of tumor pathogenesis,and the formation of tumor microenvironment regulated by the tumor toxin vena is the root of alienation of tumor development.Guided by this theory,focusing on the correlation between collateral Qi and tumor energy metabolism,using Professor Hua Baojin's treatment method of“Regulating Qi and detoxifying”to prescribe drugs can adjust collateral Qi function,achieve the relative balance of internal environment,and then inhibit the progress of tumor.Based on the above understanding,this study tries to enlighten new diagnosis and treatment ideas under the guidance of“stagnation of collateral Qi”in traditional Chinese medicine,in order to provide some theoretical support for the intervention of traditional Chinese medicine in the process of tumor development.
基金This work was supported by Beijing TCM science and Technology Development Fund Project(No.JJ-2020-43)The sixth batch of Beijing TCM master-apprentice work project+2 种基金Cheng Hongjie famous doctor inheritance studio,Fangshan hospital,Beijing University of Chinese Medicine1234 talent project of Fangshan Hospital,Beijing University of Chinese MedicineNew Teachers Launch Fund Project,Fangshan hospital,Beijing University of Chinese Medicine.(No.2021-BUCMXJKY044).
文摘Introduction:Functional Constipation(FC)is a type of functional bowel disease that is in Clinically characterized by dysportia,decreased frequency of bowel movements,or incomplete bowel movements in the absence of irritable bowel syndrome syndrome,at least 6 months before diagnosis,and symptoms within the last 3 months.At present,commonly used drugs include enema and suppositories,laxatives,microecological preparations,gastrointestinal motility drugs and other treatments.However,the effect is limited.Traditional Chinese medicine(TCM)treatment of FC has advantages.Methods:In this randomized controlled study,244 eligible patients were randomly assigned in a 1:1 ratio to a treatment group(Zangfu ointment and massage therapy+Lactulose Oral Liquid)and a control group(Lactulose Oral Liquid)for 14 days.Number of spontaneous defecation per week and First defecation time will be used as primary outcomes,and Traditional Chinese Medicine(TCM)syndrome scores and syndrome scores,PAC-QOL form will be used as secondary outcomes.Blood routine,liver function,and renal function will be used as safety outcomes.The primary and secondary outcomes will be performed at 0th,7th,and 14th day,and the safety outcomes will be performed at 0th and 14th day.Ethics and dissemination:Ethical approval has been obtained from the Committee on Health Research Ethics of the Fangshan Hospital,Beijing University of Chinese Medicine,Beijing,People's Republic of China(FZY LK-2020-010)on September 18,2020.All patients will be provided oral and written information about the trial before screening.The study results will be disseminated by peer-review publications and conference presentations.Trial registration number:ChiCTR2000038754(registered on April 14,2021).This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial license,which permits others to distribute,remix,adapt,build upon this work non-commercially,and license their derivative works on different terms,provided the original work is properly cited,appropriate credit is given,any changes made indicated,and the use is non-commercial.STRENGTHS AND LIMITATIONS OF THIS STUDY(1)The efficacy of the Zangfu ointment and massage therapy is evaluated in a randomised,double-blind 2-week clinical trial in FC patients.(2)Form a complete and generalizable regimen for the treatment of FC(Qi stagnation)with the Zangfu ointment and massage therapy.
基金Supposed by National Natural Science Foundation of China(Grant No.51075348)Hebei Provincial Natural Science Foundation of China(Grant No.E2011203151)Research Fund for Doctoral Program of Higher Education of China(Grant No.20101333110002)
文摘The double flapper-nozzle servo valve is widely used to launch and guide the equipment. Due to the large instantaneous flow rate of servo valve working under specific operating conditions, the temperature of servo valve would reach 120℃ and the valve core and valve sleeve deform in a short amount of time. So the control precision of servo valve significantly decreases and the clamping stagnation phenomenon of valve core appears. In order to solve the problem of degraded control accuracy and clamping stagnation of servo valve under large temperature difference circumstance, the numerical simulation of heat-fluid-solid coupling by using finite element method is done. The simulation result shows that zero position leakage of servo valve is basically impacted by oil temperature and change of fit clearance. The clamping stagnation is caused by warpage-deformation and fit clearance reduction of the valve core and valve sleeve. The distribution roles of the temperature and thermal-deformation of shell, valve core and valve sleeve and the pressure, velocity and temperature field of flow channel are also analyzed. Zero position leakage and electromagnet's current when valve core moves in full-stroke are tested using Electro-hydraulic Servo-valve Characteristic Test-bed of an aerospace sciences and technology corporation. The experimental results show that the change law of experimental current at different oil temperatures is roughly identical to simulation current. The current curve of the electromagnet is smooth when oil temperature is below 80℃, but the amplitude of current significantly increases and the hairy appears when oil temperature is above 80℃. The current becomes smooth again after the warped valve core and valve sleeve are reground. It indicates that clamping stagnation is caused by warpage-deformation and fit clearance reduction of valve core and valve sleeve. This paper simulates and tests the heat-fluid-solid coupling of double flapper-nozzle servo valve, and the obtained results provide the reference value for the design of double flapper-nozzle force feedback servo valve.
文摘When perforating with an abrasive water jet, it is possible that the pressure in the hole (perforation) will be higher than that in the annulus because of water jet blasting against the hole wall, which also is the theoretical basis for the technology of hydro-jet fracturing. This paper analyzes the mechanism of generating pressure stagnation in water jet hole, and puts forward a new concept of hydroseal. Then, the distribution of pressure in the hole was simulated with the finite element method. The simulation results showed that the pressure in the hole was higher than that in the annulus. Also, the lower the annular pressure (confining pressure) and the higher the blasting pressure, the greater the pressure difference. An experiment indicated that the cement sample was lifted up under the pressure stagnation in the hole, which proved the finite element simulation results obviously.
基金supported by National High-tech R&D Program of China (No. 2006AA09Z357)the National Science Foundation of China (No. 50876114, No. 10602043)+1 种基金the Program for New Century Excellent Talents in University (NCET-07-0843) and SRF for ROCS, SEMsupported by the State Key Laboratory of Multiphase Flow in Power Engineering (Xi'an Jiaotong University)
文摘In this paper a mathematical model is built for a buried hot crude oil pipeline during shutdown, and an unstructured grid and polar coordinate grid are respectively applied to generating grids for the soil region and the three layers in the pipe (wax layer, pipe wall, and corrosion-inhibiting coating). The governing equations are discretized using the finite volume method. The variations in temperatures of static oil and soil were investigated during pipeline shutdown in both summer and winter, in which some important parameters of the soil and crude oils of a Northeast pipeline are employed.