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Study on syndrome distribution and medication characteristics of patients with rectal cancer in the real world
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作者 GAO Feng GUO Li‑jun +4 位作者 XIE Yan‑ming LIU Huan ZHANG Yin LU Qi ZHUANG Yan 《Journal of Hainan Medical University》 2022年第23期50-57,共8页
Objective:To explore the general characteristics,traditional Chinese medicine(TCM)syndromes and medication of patients with rectal cancer in China.Methods:The clinical data of inpatients with rectal cancer from the in... Objective:To explore the general characteristics,traditional Chinese medicine(TCM)syndromes and medication of patients with rectal cancer in China.Methods:The clinical data of inpatients with rectal cancer from the information system of 17 tertiary A‑level traditional Chinese medicine hospitals in China were collected.After data standardization,descriptive analysis was performed on the general information,syndrome distribution and medication characteristics of the included patients,and association rule analysis was performed on the drug usage.Results:A total of 15424 hospitalized patients with rectal cancer were included.The ratio of male to female patients was 1.6:1,the average age was 60.87 years old,and the age was mainly in the range of 50 to 79 years old.Among the 12146 patients with rectal cancer,the top 5 TCM syndromes were Qi and Yin deficiency syndrome(25%),phlegm and blood stasis syndrome(19%),spleen deficiency syndrome(14%),Qi stagnation and blood stasis syndrome(7%)and Qi and blood deficiency syndrome(6%).After excluding the anti‑tumor western medicine recommended by the guidelines,adrenal corticosteroids(43.55%),antibiotics(42.94%)and immunomodulatory drugs(42.66%)ranked the top three in the frequency of western medicine use.Dexamethasone(38.15%),metoclopramide tablets(20.51%)and furosemide injection(19.71%)were the three most commonly used western medicines.Among the three western medicines combined,cimetidine,granisetron hydrochloride dextrose injection+dexamethasone were the most common(support 8.23%,confidence 96.4%,and improvement 2.48%).Heat‑clearing and detoxifying agents(53.72%),Yiqi‑fuzheng agents(49.76%)and blood‑activating and stasis‑removing agents(15.68%)ranked the top 3 in the frequency of use of traditional Chinese medicine.Shenqi Fuzheng injection,Shenqi Fuzheng injection(21.59%),Compound Kushen injection(17.52%)and Aidi injection(11.96%)were the three most commonly used Chinese patent medicines.Conclusion:The main syndromes of patients with rectal cancer may be Qi and Yin deficiency syndrome,phlegm and blood stasis syndrome,and spleen deficiency syndrome,etc.The treatment needs to focus on the supplementation of vital essence,combination of dredging and tonifying method,and the integration of traditional Chinese and western medicine. 展开更多
关键词 Real‑world data Rectal cancer Hospital information system Syndrome distribution medication characteristics
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Gravel hardness effect on compaction characteristics of gravelly soil
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作者 SHI Yunfang LI Shengang +1 位作者 JIANG Chen LIU Jinning 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1432-1443,共12页
The compaction characteristics of gravelly soil are affected by gravel hardness.To investigate the evolution and influencing mechanism of different gravel hardness on the compaction characteristics of gravelly soil,he... The compaction characteristics of gravelly soil are affected by gravel hardness.To investigate the evolution and influencing mechanism of different gravel hardness on the compaction characteristics of gravelly soil,heavy compaction tests and crushing tests were conducted on gravelly soils with gravels originated from hard,soft and extremely soft rocks.According to orthogonal experiments and variance analysis,it was found that hardness has a significant impact on the maximum dry density of gravelly soil,followed by gravel content,and lastly,moisture content.For gravel compositions with an average saturated uniaxial compressive strength less than 60 MPa,the order of compacted maximum dry density is soft gravels>hard gravels>extremely soft gravels.Each type of gravelly soil has a threshold for gravel content,with 60%for hard and soft gravels and 50%for extremely soft gravels.Beyond these thresholds,the compacted dry density decreases significantly.There is a certain interaction between hardness,gravel content,and moisture content.Higher hardness increases the influence of gravel content,whereas lower hardness increases the influence of moisture content.Gravelly soils with the coarse aggregate(CA)between 0.7 and 0.8 typically achieve higher dry densities after compaction.In addition,the prediction equations for the particle breakage rate and CA ratio in the Bailey method were proposed to estimate the compaction performance of gravelly soil preliminarily.The results further revealed the compaction mechanism of different gravelly soils and can provide reference for subgrade filling construction. 展开更多
关键词 Gravelly soil HARDNESS Compaction characteristics Crushing characteristics Particle breakage rate Bailey method
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Sleep quality and characteristics of older adults with acute cardiovascular disease
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作者 Haroon Munir Michael Goldfarb 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第3期369-373,共5页
Sleep plays a vital role in restoring the physical and mental health of people with cardiovascular disease.However,the hospital setting is not a conducive environment for sleep.Sleep interruptions by members of the ca... Sleep plays a vital role in restoring the physical and mental health of people with cardiovascular disease.However,the hospital setting is not a conducive environment for sleep.Sleep interruptions by members of the care team,including vital sign checks,medication delivery,and blood draws for laboratory investigations,are routinely done in many hospitals.Frequent interruptions by staff and noise by other patients have been cited as barriers to restorative sleep in the hospital. 展开更多
关键词 SLEEP ROUTINE characteristics
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Some of the Chemical and Physical Characteristics of the Graff River in Kut City, Iraq
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作者 Salih Mahdi Ali Imad Kazem Ali 《Open Journal of Modern Hydrology》 CAS 2024年第1期56-67,共12页
Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period fro... Some of the chemical and physical water qualities of the Graff River in the city of Kut were studied, and for two sites of the river, One was at the Crimea site, the other in the Jihad district, and for the period from October/2018 to March/2019, Seven variables of river water have been analyzed: temperature PH, electrical conductivity, TDS, turbidity, alkaline, and chloride. The results showed that most of the chemical and physical water properties of the river were in normal proportions and did not rise, except for the turbidity, which was at a very high level, and that the pH values were close to the basal side. The results of the statistical analysis revealed positive significant relationships between the pH and (chloride and TDS). On the other hand, between electrical conductivity and both previous variables as well. And a negative significant connection between temperature and alkaline. 展开更多
关键词 Graff River Kut City Iraq Chemical characteristics Physical characteristics
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The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation
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作者 Hao Zhang Yan Zhang +2 位作者 Wei Liu Ximin Zhang Xiang Liu 《Energy Engineering》 EI 2024年第1期27-42,共16页
The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to ... The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation.The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion.And a 15%concentration of hydrochloric acid can effectively dissolve shale.Furthermore,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir section.After the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale decreased.Moreover,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume modification.This discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources. 展开更多
关键词 SHALE acid fracturing macro characteristics microscopic characteristics mechanical properties
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Research on the influences of motion characteristics of jetting projectile charge under water
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作者 Xing Chen Yong-gang Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期411-425,共15页
Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of... Shaped charge warhead is important for enhancing the damage performance of underwater weapons.This paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in water.The findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying exponentially.Increasing the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the JPC.The optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in water.Material density plays a crucial role in the velocity decay pattern of the JPC during penetration.JPC with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are similar.Consequently,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge warhead.Finally,the results will provide an important reference for the design of underwater shaped charge warhead. 展开更多
关键词 JPC Movement characteristics Underwater penetration Numerical simulation
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Informing policy makers in developing countries:Practices and limitations of geriatric home medication review in Malaysia-A qualitative inquiry
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作者 Ahlam Sundus Renukha Sellappans Tan Maw Pin 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期21-29,I0001-I0003,共12页
Objective:To explore existing practices and challenges in the delivery of geriatric home medication review(HMR).The study was part of a larger study aimed to offer solution to expand the range of geriatric HMR.Methods... Objective:To explore existing practices and challenges in the delivery of geriatric home medication review(HMR).The study was part of a larger study aimed to offer solution to expand the range of geriatric HMR.Methods:This study employed qualitative exploratory design through semi-structured individual in-depth interviews with the public pharmacists involved in the delivery of geriatric HMR at public hospitals.The purpose of the interviews was to explore challenges faced by them in the delivery of geriatric HMR.Results:Based on the emerging themes from the qualitative data,the study reveals that geriatric HMR in Malaysia is integrated as part of multidisciplinary home care visits,encompassing a diverse patient population with various healthcare needs.However,it faces challenges such as the lack of outcome monitoring,formal training,and workforce constraints.Despite these hurdles,there is a pressing need for the expansion of this service to better serve the community,and collaboration with community pharmacists holds potential to broaden its scope.Ultimately,the findings suggest that pharmacist-led HMR is both warranted and feasible within the Malaysian healthcare context.In order to optimize medicine-use among older people living in the community,approaches for expanding geriatric HMR services in Malaysia must be developed.Conclusions:This study holds profound implications as it attempts to illuminate policy makers in developing countries,enabling them to formulate effective HMR plans.By considering the challenges highlighted within this research,policy makers can design a comprehensive HMR service that caters adeptly to the healthcare needs of the mass population. 展开更多
关键词 Home medication review Older adults MALAYSIA PHARMACISTS Low-to-middle-income countries
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Study of Pyrolysis Characteristics and Kinetic Analysis of Shenmu Coal at a High Heating Rate Using TG-FTIR
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作者 An Xiaoxi Zhang Yanpeng +2 位作者 Shang Yanchao Tian Yuanyu Qiao Yingyun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期47-55,共9页
Coal pyrolysis is a fundamental reaction in the thermal processing and utilization of coal.Investigating the behavior and kinetics of coal pyrolysis is crucial for optimizing,designing,and developing a composite riser... Coal pyrolysis is a fundamental reaction in the thermal processing and utilization of coal.Investigating the behavior and kinetics of coal pyrolysis is crucial for optimizing,designing,and developing a composite riser for the staged pyrolysis gasification process of pulverized coal.In this study,the non-isothermal pyrolysis behavior and kinetics of coal were examined at different heating rates(30,50,100,300,500,700,and 900℃/min)using thermogravimetry(TG)coupled with Fourier-transform infrared spectroscopy.Analysis of the TG/derivative TG(TG/DTG)curves indicated that coal pyrolysis mainly occurred between 300℃ and 700℃.Higher heating rates led to more volatiles being released from the coal,and a higher temperature was required to achieve rapid pyrolysis.Kinetic analysis showed that both the model-free methods(Friedman,Flynn-Wall-Ozawa,and Kissinger-Akahira-Sunose)and the model-based method(Coats-Redfern)effectively describe the coal pyrolysis process.The change in the Ea values between the two kinetic models was consistent throughout the pyrolysis process,and the most probable mechanism was the F2 model(secondary chemical reaction).In addition,the heating rate did not change the overall reaction order of the pyrolysis process;however,a higher heating rate resulted in a decrease in the Ea value during the initial pyrolysis stage. 展开更多
关键词 coal pyrolysis TG-FTIR characteristic parameters DYNAMICS
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Advancements in Medication Rule for Pulmonary Nodules: A Review of Current Research Progress
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作者 Weilan Lin Shun Chen Feng Lu 《Journal of Biosciences and Medicines》 2024年第3期193-203,共11页
This paper reviewed the literature on medication rule of pulmonary nodules in recent years. It is found that contemporary doctors pay more attention to regulating Qi, clearing heat and detoxifying, eliminating phlegm,... This paper reviewed the literature on medication rule of pulmonary nodules in recent years. It is found that contemporary doctors pay more attention to regulating Qi, clearing heat and detoxifying, eliminating phlegm, dissolving phlegm and dissipating masses. They use mild drugs, cold and warm treatments in parallel, combining the tastes of pungent, bitterness, and sweetness at the same time. The treatment focuses on the five viscera with emphasis on the lung meridian while also considering the spleen and stomach functions as well as soothing liver stagnation. This information aims to provide some reference for clinical treatment of pulmonary nodules. 展开更多
关键词 Pulmonary Nodules medication Rule REVIEW
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Jet Characteristics and Optimization of a Cavitation Nozzle for Hydraulic Fracturing Applications
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作者 Yu Gao Zhenqiang Xu Kaixiang Shen 《Fluid Dynamics & Materials Processing》 EI 2024年第1期179-192,共14页
Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perfora... Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perforation tool.In this study,the flow behavior of the nozzle is simulated numerically in the framework of a SST k-ωturbulence model.The results show that the nozzle structure can significantly influence the jet performance and related cavitation effect.Through orthogonal experiments,the nozzle geometric parameters are optimized,and the following configuration is found accordingly:contraction angle 20°,contraction segment length 6 mm,cylindrical segment diameter 6 mm,cylindrical segment length 12 mm,spread segment length 10 mm,and spread angle 55°. 展开更多
关键词 Cavitation jet angle nozzle hydraulic characteristics nozzle parameters
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Research Progress of Measuring Tools for Patient Medication Compliance
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作者 Chengping Jian Xiangdong Peng +3 位作者 Haiyan Tian Liying Wang Yanan Zhang Defang Cai 《Journal of Biosciences and Medicines》 2024年第2期225-235,共11页
This paper introduced the content, compilation process, reliability and validity, scoring method of the evaluation tool for patients’ medication compliance at home and abroad, and reviewed the research progress of th... This paper introduced the content, compilation process, reliability and validity, scoring method of the evaluation tool for patients’ medication compliance at home and abroad, and reviewed the research progress of the tool. The evaluation method, dimension, scoring method, evaluation content and application scope of the tool were compared, so as to provide reference for nurses to comprehensively and accurately evaluate patients’ medication status. 展开更多
关键词 medication Compliance Assessment Tool Research Progress
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Dynamic response mechanism and precursor characteristics of gneiss rockburst under different initial burial depths
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作者 LIU Dongqiao SUN Jie +4 位作者 MENG Wen HE Manchao ZHANG Chongyuan LI Ran CAO Binghao 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1004-1018,共15页
To investigate the influence mechanism of geostress on rockburst characteristics,three groups of gneiss rockburst experiments were conducted under different initial geostress conditions.A high-speed photography system... To investigate the influence mechanism of geostress on rockburst characteristics,three groups of gneiss rockburst experiments were conducted under different initial geostress conditions.A high-speed photography system and acoustic emission(AE)monitoring system were used to monitor the entire rockburst process in real time.The experimental results show that when the initial burial depth increases from 928 m to 1320 m,the proportion of large fracture scale in rockburst increases by 154.54%,and the AE energy increases by 565.63%,reflecting that the degree and severity of rockburst increase with the increase of burial depth.And then,two mechanisms are proposed to explain this effect,including(i)the increase of initial geostress improves the energy storage capacity of gneiss,and then,the excess energy which can be converted into kinetic energy of debris ejection increases,consequently,a more pronounced violent ejection phenomenon is observed at rockburst;(ii)the increase of initial geostress causes more sufficient plate cracks of gneiss after unloading ofσh,which provides a basis for more severe ejection of rockburst.What’s more,a precursor with clear physical meaning for rockburst is proposed under the framework of dynamic response process of crack evolution.Finally,potential value in long term rockburst warning of the precursor obtained in this study is shown via the comparison of conventional precursor. 展开更多
关键词 Traffic Engineering Gneiss Rockburst Crack propagation Excess energy Precursor characteristic
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The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys
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作者 Jia-yu Meng Jing-zhi He +4 位作者 Bin Zhang Jin Chen Shun Li Dun Niu Yu Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期343-350,共8页
Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-elem... Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were studied.The microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of Ti.While the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of Zr.The evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta alloys.The synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation movement.And as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually increase.The higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content. 展开更多
关键词 Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics
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Experimental study of the damage characteristics of rocks containing non-penetrating cracks under cyclic loading
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作者 Jun Xu Xiaochun Xiao +3 位作者 Lu Ma Sen Luo Jiaxu Jin Baijian Wu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期197-210,共14页
The damage evolution process of non-penetrating cracks often causes some unexpected engineering disasters.Gypsum specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics ... The damage evolution process of non-penetrating cracks often causes some unexpected engineering disasters.Gypsum specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics under cyclic loading.The results show that under cyclic loading,the relationship between the number of non-penetrating crack(s)and the characteristic parameters(cyclic number,peak stress,peak strain,failure stress,and failure strain)of the pre-cracked specimens can be represented by a decreasing linear function.The damage evolution equation is fitted by calibrating the accumulative plastic strain for each cycle,and the damage constitutive equation is proposed by the concept of effective stress.Additionally,non-penetrating cracks are more likely to cause uneven stress distribution,damage accumulation,and local failure of specimen.The local failure can change the stress distribution and relieve the inhibition of non-penetrating crack extension and eventually cause a dramatic destruction of the specimen.Therefore,the evolution process caused by non-penetrating cracks can be regarded as one of the important reasons for inducing rockburst.These results are expected to improve the understanding of the process of spalling formation and rockburst and can be used to analyze the stability of rocks or rock structures. 展开更多
关键词 Damage characteristics Constitutive model Fissured rocks Non-penetrating crack Cyclic loading
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Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal
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作者 Linghui Zeng Zhongqi Wang +1 位作者 Xing Chen Jianping Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期484-495,共12页
The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation f... The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is built.The concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation field.The phase and component changes of fuel cloud at different locations are compared.The fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 K.The highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,respectively.The stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge. 展开更多
关键词 Fuel dispersal Concentration distribution Detonation characteristic Fuel loss Numerical simulation
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Deformation Characteristics of Hydrate-Bearing Sediments
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作者 DONG Lin LI Yanlong +4 位作者 ZHANG Yajuan HU Gaowei LIAO Hualin CHEN Qiang WU Nengyou 《Journal of Ocean University of China》 CAS CSCD 2024年第1期149-156,共8页
The safe and efficient development of natural gas hydrate requires a deep understanding of the deformation behaviors of reservoirs.In this study,a series of triaxial shearing tests are carried out to investigate the d... The safe and efficient development of natural gas hydrate requires a deep understanding of the deformation behaviors of reservoirs.In this study,a series of triaxial shearing tests are carried out to investigate the deformation properties of hydrate-bearing sediments.Variations of volumetric and lateral strains versus hydrate saturation are analyzed comprehensively.Results indicate that the sediments with high hydrate saturation show dilative behaviors,which lead to strain-softening characteristics during shearing.The volumetric strain curves have a tendency to transform gradually from dilatation to compression with the increase in effective confining pressure.An easy prediction model is proposed to describe the relationship between volumetric and axial strains.The model coefficientβis the key dominating factor for the shape of volumetric strain curves and can be determined by the hydrate saturation and stress state.Moreover,a modified model is established for the calculation of lateral strain.The corresponding determination method is provided for the easy estimation of model coefficients for medium sand sediments containing hydrate.This study provides a theoretical and experimental reference for deformation estimation in natural gas hydrate development. 展开更多
关键词 gas hydrate deformation characteristics volumetric strain lateral strain prediction model
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Present-day movement characteristics of the Qinghai Nanshan fault and its surrounding area from GPS observation
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作者 Yang Liu Yuxuan Qiu +5 位作者 Jialiang Liu Luyun Xiong Caijun Xu Jianghui Geng Gang Zheng Tianchen Sheng 《Geodesy and Geodynamics》 EI CSCD 2024年第2期133-141,共9页
The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transfo... The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet clear.This study uses data fusion to obtain denser GPS observations near the Qinghai Nanshan fault.Based on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip deficit.The results show that the Qinghai Nanshan fault slip rate is characterized by sinistral and convergent movement.Both the sinistral and convergent rates display a decreasing trend from west to east.The locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern segment.Then,we construct a strain rate field using GPS observations to analyze the regional strain characteristics.The results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation rate.Regional earthquake records show that the frequency of earthquakes is lower near the fault.The joint results suggest that the western segment may have a higher earthquake risk.In addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults. 展开更多
关键词 The Qinghai Nanshan fault Movement characteristics Block model Slip rate GPS
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Short-time maritime target detection based on polarization scattering characteristics
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作者 CHEN Shichao LUO Feng +1 位作者 TIAN Min LYU Wanghan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期55-64,共10页
In this paper,a detection method combining Cameron decomposition based on polarization scattering characteristics in sea clutter background is proposed.Firstly,the Cameron decomposition is exploited to fuse the radar ... In this paper,a detection method combining Cameron decomposition based on polarization scattering characteristics in sea clutter background is proposed.Firstly,the Cameron decomposition is exploited to fuse the radar echoes of full polarization channels at the data level.Due to the artificial material structure on the surface of the target,it can be shown that the non-reciprocity of the target cell is stronger than that of the clutter cell.Then,based on the analysis of the decomposition results,a new feature with scattering geometry characteristics in polarization domain,denoted as Cameron polarization decomposition scattering weight(CPD-SW),is extracted as the test statistic,which can achieve more detailed descriptions of the clutter scattering characteristics utilizing the difference between their scattering types.Finally,the superiority of the proposed CPD-SW detector over traditional detectors in improving detection performance is verified by the IPIX measured dataset,which has strong stability under short-time observation in threshold detection and can also improve the separability of feature space zin anomaly detection. 展开更多
关键词 sea clutter small target radar detection Cameron decomposition characteristics analysis
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Flow Field Characteristics of Multi-Trophic Artificial Reef Based on Computation Fluid Dynamics
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作者 HUANG Junlin LI Jiao +3 位作者 LI Yan GONG Pihai GUAN Changtao XIA Xu 《Journal of Ocean University of China》 CAS CSCD 2024年第2期317-327,共11页
On the basis of computational fluid dynamics,the flow field characteristics of multi-trophic artificial reefs,including the flow field distribution features of a single reef under three different velocities and the ef... On the basis of computational fluid dynamics,the flow field characteristics of multi-trophic artificial reefs,including the flow field distribution features of a single reef under three different velocities and the effect of spacing between reefs on flow scale and the flow state,were analyzed.Results indicate upwelling,slow flow,and eddy around a single reef.Maximum velocity,height,and volume of upwelling in front of a single reef were positively correlated with inflow velocity.The length and volume of slow flow increased with the increase in inflow velocity.Eddies were present both inside and backward,and vorticity was positively correlated with inflow velocity.Space between reefs had a minor influence on the maximum velocity and height of upwelling.With the increase in space from 0.5 L to 1.5 L(L is the reef lehgth),the length of slow flow in the front and back of the combined reefs increased slightly.When the space was 2.0 L,the length of the slow flow decreased.In four different spaces,eddies were present inside and at the back of each reef.The maximum vorticity was negatively correlated with space from 0.5 L to 1.5 L,but under 2.0 L space,the maximum vorticity was close to the vorticity of a single reef under the same inflow velocity. 展开更多
关键词 artificial reef flow field characteristics computation fluid dynamics multi-trophic structure
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Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress
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作者 WEI Huanhe GENG Xiaoyu +7 位作者 ZHANG Xiang ZHU Wang ZHANG Xubin CHEN Yinglong HUO Zhongyang ZHOU Guisheng MENG Tianyao DAI Qigen 《Rice science》 SCIE CSCD 2024年第1期118-128,I0023,共12页
Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinit... Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield. 展开更多
关键词 antioxidant defense system combined salinity-drought stress drought stress photosynthetic characteristics RICE salinity stress
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