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Experimental study of the influencing factors and mechanisms of the pressure-reduction and augmented injection effect by nanoparticles in ultra-low permeability reservoirs
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作者 Pan Wang Yu-Hang Hu +8 位作者 Liao-Yuan Zhang Yong Meng Zhen-Fu Ma Tian-Ru Wang Zi-Lin Zhang Ji-Chao Fang Xiao-Qiang Liu Qing You Yan Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1915-1927,共13页
Nanoparticles(NPs)have gained significant attention as a functional material due to their ability to effectively enhance pressure reduction in injection processes in ultra-low permeability reservoirs.NPs are typically... Nanoparticles(NPs)have gained significant attention as a functional material due to their ability to effectively enhance pressure reduction in injection processes in ultra-low permeability reservoirs.NPs are typically studied in controlled laboratory conditions,and their behavior in real-world,complex environments such as ultra-low permeability reservoirs,is not well understood due to the limited scope of their applications.This study investigates the efficacy and underlying mechanisms of NPs in decreasing injection pressure under various injection conditions(25—85℃,10—25 MPa).The results reveal that under optimal injection conditions,NPs effectively reduce injection pressure by a maximum of 22.77%in core experiment.The pressure reduction rate is found to be positively correlated with oil saturation and permeability,and negatively correlated with temperature and salinity.Furthermore,particle image velocimetry(PIV)experiments(25℃,atmospheric pressure)indicate that the pressure reduction is achieved by NPs through the reduction of wall shear resistance and wettability change.This work has important implications for the design of water injection strategies in ultra-low permeability reservoirs. 展开更多
关键词 NANOPARTICLE pressure reduction Augmented injection Ultra-low permeability reservoir
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Background diseases and the number of previous intravitreal aflibercept injections on immediate intraocular pressure increase and vitreous reflux rate in phakic eyes
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作者 Tetsuya Muto Shigeki Machida Shinichiro Imaizumi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期545-550,共6页
●AIM:To evaluate the effect of background diseases and number of previous intravitreal aflibercept injections(IVAIs)on immediate intraocular pressure(IOP)increase and vitreous reflux(VR)rate and to evaluate the corre... ●AIM:To evaluate the effect of background diseases and number of previous intravitreal aflibercept injections(IVAIs)on immediate intraocular pressure(IOP)increase and vitreous reflux(VR)rate and to evaluate the correlation of both age and axial length with immediate IOP increase and VR rate.●METHODS:This study included 105 patients with cystoid macular edema secondary to retinal vein occlusion,35 patients with diabetic macular edema,69 patients with neovascular age-related macular degeneration(nAMD),and 12 patients with myopic choroidal neovascularization,which underwent first-time IVAI.The correlation of immediate IOP increase and VR rates with the four background diseases was investigated.Moreover,the correlation of age with immediate IOP increase and VR rate as well as correlation of axial length with immediate IOP increase and VR rate were evaluated.Further,54 patients with nAMD were treated with IVAI>10 times(multiple IVAIs).Moreover,the correlation of immediate IOP increase and VR rates with first-time and multiple IVAIs in nAMD was determined.●RESULTS:The immediate IOP increase(P=0.16)and VR rates(P=0.50)were almost similar among the four background diseases.The immediate postinjection IOP and age,VR rate and age,immediate postinjection IOP and axial length,or VR rate and axial length were not correlated in the four background diseases.The immediate IOP increase(P=0.66)and VR rates(P=0.28)did not significantly differ between first-time and multiple IVAIs in nAMD.●CONCLUSION:Background diseases and number of previous IVAIs have no effect on immediate IOP increase and VR rate.Further,age and axial length have no correlation on immediate IOP increase and VR rate. 展开更多
关键词 AFLIBERCEPT intraocular pressure vitreous reflux intravitreal injection
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Short-term fluctuation of intraocular pressure and influencing factors following intravitreal injection in patients with retinal vascular diseases
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作者 Jing-Peng Miao Yi-Yun Zeng +1 位作者 Xin-Ming Gu Xin-Yuan Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2052-2059,共8页
AIM:To investigate the patterns of short-term intraocular pressure(IOP)fluctuations and identify the contributing factors following intravitreal injection in patients with retinal vascular diseases.METHODS:Totally 81 ... AIM:To investigate the patterns of short-term intraocular pressure(IOP)fluctuations and identify the contributing factors following intravitreal injection in patients with retinal vascular diseases.METHODS:Totally 81 patients were enrolled in this case control study.Eyes were categorized into 7 groups,including age-related macular degeneration(AMD),polypoidal choroidal vasculopathy(PCV),idiopathic choroidal neovascularization(CNV),proliferative diabetic retinopathy(PDR),diabetic macular edema(DME),macular edema secondary to branch(BVOME)and central(CVOME)retinal vein occlusion.IOP was measured in all patients using rebound tonometer at 7 preset time points perioperatively.Additionally,based on the administered medication,the eyes were classified into three treatment groups,including dexamethasone intravitreal implant(IVO),intravitreal conbercept(IVC),and intravitreal ranibizumab(IVR).To compare IOP values at various time points across groups,we employed one-way ANOVA,independent sample t-test or χ^(2) test and multivariate logistic regression analysis.RESULTS:Peak IOP values across all groups were observed at 40s,and 5min after intravitreal injection.Statistical differences in IOP were detected at the 5min among the 7 indication groups(F=2.50,P=0.029).When examing the impact of medications,the IVO group exhibited lower average IOP values at both 40s and 5min compared to the IVC and IVR groups(P<0.001;P=0.007).The IOP values at 40s and 5min were significantly higher in BVOME and CVOME group compared to non-retinal vein occlusionsecondary macular edema(RVOME)group(P<0.001).Multivariate logistic regression analysis further confirmed that IOP measurement at 40s was significantly higher in CVOME group than in non-RVOME group(OR=1.64,95%CI:1.09-2.47;P=0.018).CONCLUSION:Needle size plays a crucial role in the transient changes of IOP following intravitreal injection.Before administering intravitreal injection to patients with central retinal vein occlusion,it is essential to exclude any underlysing causes of increased IOP. 展开更多
关键词 intravitreal injection rebound tonometer intraocular pressure retinal vein occlusion ocular fundus diseases
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Analysis of the Emissions and Performance of a Diesel Engine Using Pumpkin Seed Oil Methyl Ester with Different Injection Pressures
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作者 Surendrababu Kuppusamy Prabhahar Muthuswamy +1 位作者 Muthurajan Kumarasamy Sendilvelan Subramanian 《Fluid Dynamics & Materials Processing》 EI 2023年第4期1003-1014,共12页
Biodiesel fuel is a potential alternative energy source for diesel engines due to its physiochemical characteristics relatively similar to those of traditional diesel fuel.In this study,the performance,emission,and co... Biodiesel fuel is a potential alternative energy source for diesel engines due to its physiochemical characteristics relatively similar to those of traditional diesel fuel.In this study,the performance,emission,and combustion features of a mono cylinder DI diesel engine are assessed using 20%Pumpkin seed methyl ester(PSOME20)and considering varying injection pressures(200,220,240,and 260 bar).The considered Pumpkin seed oil is converted into pumpkin biodiesel by transesterification and then used as fuel.The findings demonstrate that the Brake Thermal Efficiency(BTE)of PSOME20 can be raised by 1.68%,and the carbon monoxide(CO),hydrocarbon(HC),and smoke emanations can be lowered,while oxides of nitrogen(NOx)emissions are increased at an injection pressure(IP)of 240 bar compared to the standard IP of 200 bar.The cylinder pressure and the Heat Release Rate(HRR)become higher at 240 bar,whereas the ignition delay is shortened with respect to PSOME20 at a normal IP of 200 bar. 展开更多
关键词 Pumpkin seed biodiesel PERFORMANCE EMISSION diesel engine injection pressure
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Optimization of the Algorithm for Increasing Injection Rate in Water Injection Wells for Pressure Optimization in P Oilfield
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作者 Lingyu Li 《World Journal of Engineering and Technology》 2023年第2期246-251,共6页
In today’s society, with the continuous growth of energy demand, Bohai Oilfield, as an important offshore oil resource base in China, is facing increasingly severe challenges while contributing to national energy sec... In today’s society, with the continuous growth of energy demand, Bohai Oilfield, as an important offshore oil resource base in China, is facing increasingly severe challenges while contributing to national energy security. In order to improve the quality of water injection in the oilfield and gradually achieve efficient and stable production, Bohai Oilfield has launched a water injection well pressure optimization project, focusing on improving the efficiency and quality of water injection in the water injection wells, in order to achieve the optimal water injection plan. In practical work, P Oilfield continues to promote the development of water injection well pressure optimization projects, emphasizing practical exploration and continuous optimization of work plans. However, during the project implementation process, there were some problems, one of which was that the statistics of cumulative injection volume were not scientific enough, resulting in a more comprehensive and accurate presentation of the actual results of pressure optimization work. In the context of continuous improvement work, after careful analysis and research, P Oilfield has decided to optimize the cumulative injection rate algorithm to guide the oilfield’s water injection work in a more refined way, ensuring sufficient and good water injection, and enhancing the oilfield’s production efficiency and comprehensive competitiveness. 展开更多
关键词 Offshore Oil Fields Water injection Wells pressure Optimization Water injection Volume Calculation Method
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Effect of Salvia Miltiorrhiza Injection on Blood Pressure and Cardiac Function in Rats with Gestational Hypertension and Preeclampsia
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作者 Xi Zhang Juan Li +3 位作者 Ping Zhou Qianqian Luo Zhaojun Xiang Hongying Wu 《Journal of Biosciences and Medicines》 2023年第12期152-160,共9页
Objective: This study is to observe the effects of Salvia miltiorrhiza injection on blood pressure and cardiac function in rats with pregnancy-induced hypertension and preeclampsia. Methodology: Syncytiotrophoblast mi... Objective: This study is to observe the effects of Salvia miltiorrhiza injection on blood pressure and cardiac function in rats with pregnancy-induced hypertension and preeclampsia. Methodology: Syncytiotrophoblast microvilli (stbm) and l-arginine nitrosyl methyl ester were screened out via caudal vein injection. Twenty gestational hypertension-preeclampsia model SD (Sprague Dawley) rats successfully induced by L-NAME (L-arginine Nitrosyl methyl ester) were randomly divided into 2 groups (model group and Danshen injection group, n = 10). Then another 10 normal pregnant SD rats without model were selected as blank control group. The Salvia miltiorrhiza injection group was given Salvia miltiorrhiza injection (0.5 g?kg?1?d?1) through tail vein, and the control group and model group were given equal volume of normal saline through tail vein injection. All three groups were treated by tail vein injection once a day (d) for 7 days. After treatment, heart rate (HR), Systolic pressure (SP), diastolic pressure (DP) and mean arterial pressure (MAP) were measured by tail artery. Left ventricular end-diastolic diameter (LVDd) and Left ventricular end systolic diameter (LVDs) were recorded by echocardiography. Left ventricular end diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), left ventricular ejection fraction (left ventricular ejection) fraction, LVEF) and the maximum rate of increase/decrease of left ventricular pressure during isovolemic systole (+dp/dtmax/?dp/dtmax);Endothelin-1 (ET-1) levels in rat tail vein blood were detected by ELISA. Results: SP, DP, MP, HR, LVSP, LVDs and ?dp/dtmaxx were all decreased, plasma ET-1 expression was low, and LVDd, LVEDP, LVEF, and +dp/dtmax were all increased in the Salvia miltiorroot injection group, with statistical significance compared to the model group (p Conclusion: Salvia miltiorrhiza injection can improve the cardiac function and reduce blood pressure in rats with pregnancy-induced hypertension and preeclampsia, and the mechanism may be related to alleviating systemic arteriolar spasm by regulating ET-1 level. 展开更多
关键词 RAT Danshen injection Pregnancy-Induced Hypertension PREECLAMPSIA ENDOTHELIN-1 Blood pressure Cardiac Function
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Immediate intraocular pressure rise after intravitreal injection of ranibizumab and two doses of triamcinolone acetonide 被引量:6
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作者 Gul Arikan Ali Osman Saatci Ferit Hakan Oner 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第4期402-405,共4页
AIM: To evaluate prospectively immediate intraocular pressure (IOP) changes after the intravitreal injection of ranibizumab, 2 and 4mg triamcinolone acetonide. METHODS: Patients who underwent intravitreal injection of... AIM: To evaluate prospectively immediate intraocular pressure (IOP) changes after the intravitreal injection of ranibizumab, 2 and 4mg triamcinolone acetonide. METHODS: Patients who underwent intravitreal injection of 0.1mL (4mg) triamcinolone acetonide (TA, Group T4), 0.05mL (2mg) TA (Group T2) and 0.05mL (0.5mg) ranibizumab (Group R) comprised the study population. Overall, 229 eyes of 205 patients were injected. Fifty-four eyes (23.6%) were in Group T4, 69 eyes (30.1%) in Group T2 and 106 eyes (46.3%) in Group R. If IOP was less than 26mmHg immediately after the injection no further measurement was performed. If IOP was ≥26mmHg, IOP was remeasured till the reading was below 26mmHg at 5, 15 and 30 minutes. RESULTS: Immediately after the injection, the IOP of 28 eyes (51.9%) in Group T4, 22 eyes (31.9%) in Group T2 and 51 eyes (48.1%) in Group R were over 25mmHg. At 30 minutes, IOP of one eye (1.9%) in group T4, two eyes (2.9%) in group T2 and two eyes (1.9 %) in Group R were over 25mmHg. Immediate post-injection IOP was significantly higher in Group T4 and Group R when compared to Group T2 (P <0.001 and P <0.001, respectively). IOP was significantly higher in eyes without vitreous reflux when compared to those with vitreous reflux in all groups (P <0.001). CONCLUSION: IOP may remarkably increase immediately after the intravitreal injection of 2 or 4mg triamcinolone acetonide, and 0.5mg ranibizumab. Absence of vitreous reflux is the most important predicting factor for immediate IOP rise after the injection. 展开更多
关键词 anti-VEGF agents GLAUCOMA intraocular pressure intravitreal injection STEROIDS
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Intraocular pressure elevation after intravitreal triamcinolone acetonide injection: a Meta-analysis 被引量:6
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作者 Cansu Yuksel-Elgin Ceyhun Elgin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第1期139-144,共6页
AIM:To report on intraocular pressure(IOP)after intravitreal injections of triamcinolone acetonide.·M ETHODS:Systematic literature review of studies that investigated the effects of an injection of triamcinol... AIM:To report on intraocular pressure(IOP)after intravitreal injections of triamcinolone acetonide.·M ETHODS:Systematic literature review of studies that investigated the effects of an injection of triamcinolone Intravitreal triamcinolone acetonide on IOP was conducted according to the Cochrane Collaboration methodology and the reported effects have been analyzed with Meta-analysis.·RESULTS:We found that the IOP follows an inverted-U shape pattern over time starting with an average value of14.81±1.22 mm Hg before the injection,rising to a maximum of 19.48±2.15 mm Hg after one month of injection and falling down to 16.16±1.92 mm Hg after6mo.Moreover,country of study,age,previous history of glaucoma and gender compositions matter for crossstudy were different in reported IOP changes.·CONCLUSION:Our findings may be helpful in determining pressure elevation risk of intravitreal triamcinolone acetonide therapy as well as comparing it with those of more recent therapies such as the antivascular endothelial growth factor agents. 展开更多
关键词 intravitreal injections intraocular pressure META-ANALYSIS
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Simulation and Experiment Research on the Proportional Pressure Control of Water-assisted Injection Molding 被引量:3
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作者 ZHOU Hua CHEN Yinglong +1 位作者 ZHANG Zengmeng YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期430-438,共9页
Water-assisted injection molding(WAIM),a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving,short cooling circle time and high quality of products.Ex... Water-assisted injection molding(WAIM),a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving,short cooling circle time and high quality of products.Existing research for the process of WAIM has shown that the pressure control of the injecting water is mostly important for the WAIM.However,the proportional pressure control for the WAIM system is quite complex due to the existence of nonlinearities in the water hydraulic system.In order to achieve better pressure control performance of the injecting water to meet the requirements of the WAIM,the proportional pressure control of the WAIM system is investigated both numerically and experimentally.A newly designed water hydraulic system for WAIM is first modeled in AMEsim environment,the load characteristics and the nonlinearities of water hydraulic system are both considered,then the main factors affecting the injecting pressure and load flow rate are extensively studied.Meanwhile,an open-loop model-based compensation control strategy is employed to regulate the water injection pressure and a feedback proportional integrator controller is further adopted to achieve better control performance.In order to verify the AMEsim simulation results WAIM experiment for particular Acrylonitrile Butadiene Styrene(ABS) parts is implemented and the measured experimental data including injecting pressure and flow rate results are compared with the simulation.The good coincidence between experiment and simulation shows that the AMEsim model is accurate,and the tracking performance of the load pressure indicates that the proposed control strategy is effective for the proportional pressure control of the nonlinear WAIM system.The proposed proportional pressure control strategy and the conclusions drawn from simulation and experiment contribute to the application of water hydraulic proportional control and WAIM technology. 展开更多
关键词 water-assisted injection molding nonlinear modeling proportional pressure control AMEsim simulation
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Research on Casing Damage Based on Effect of Water Injection Pressure 被引量:3
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作者 Liping Guo Xu Chen +2 位作者 Xiaoyang Yu Shuang Shi Yu Wang 《Open Journal of Fluid Dynamics》 2015年第2期208-214,共7页
Based on statistical analysis on the situation of casing damage and water injection pressure in Pubei Oilfield, it shows that the main forms of casing damage in Pubei Oilfield are deformation and dislocation. Dip angl... Based on statistical analysis on the situation of casing damage and water injection pressure in Pubei Oilfield, it shows that the main forms of casing damage in Pubei Oilfield are deformation and dislocation. Dip angle and faults have a significant impact on casing damage and casing damage is closely related to water injection pressure. Through laboratory simulating experiment and theoretical calculation, the formula of critical injection pressure giving rise to casing damage is obtained and the preventive measures are drafted. 展开更多
关键词 CASING DAMAGE WATER injection pressure Pubei OILFIELD
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Effect of different lens status on intraocular pressure elevation in patients treated with anti-vascular endothelial growth factor injections 被引量:2
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作者 Amir Sternfeld Rita Ehrlich +1 位作者 Dov Weinberger Assaf Dotan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第1期79-84,共6页
AIM: To assess the effect of lens status on sustained intraocular pressure(IOP) elevation in patients treated intravitreally with anti-vascular endothelial growth factor(VEGF) agents. METHODS: Data were retrospectivel... AIM: To assess the effect of lens status on sustained intraocular pressure(IOP) elevation in patients treated intravitreally with anti-vascular endothelial growth factor(VEGF) agents. METHODS: Data were retrospectively collected for all patients treated with intravitreal injections of anti-VEGF medication at a tertiary medical center in July 2015. Findings were analyzed by lens status during 6 months' follow-up. The main outcome measure was a sustained increase in IOP(≥21 mm Hg or change of ≥6 mm Hg from baseline on ≥2 consecutive visits, or addition of a new IOPlowering medication during follow-up). RESULTS: A total of 119 eyes of 100 patients met the study criteria: 40 phakic, 40 pseudophakic, and 39 pseudophakic after Nd:YAG capsulotomy. The rate of sustained IOP elevation was significantly higher in the postcapsulotomy group(23.1%) than in the phakic/pseudophakic groups(8.1%;P=0.032), with no statistically significant differences among the 3 groups in mean number of injections, either total(P=0.82) or by type of anti-VEGF mediation(bevacizumab: P=0.19;ranibizumab: P=0.13), or mean follow-up time(P=0.70). CONCLUSION: Nd:YAG capsulotomy appears to be a risk factor for sustained IOP elevation in patients receiving intravitreal anti-VEGF injections. This finding has important implications given the growing use of anti-VEGF treatment and the irreversible effects of elevated IOP. 展开更多
关键词 anti-VEGF injections cataract surgery intraocular pressure Nd:YAG capsulotomy
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A fast explicit finite difference method for determination of wellhead injection pressure 被引量:2
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作者 白冰 李小春 +2 位作者 刘明泽 石露 李琦 《Journal of Central South University》 SCIE EI CAS 2012年第11期3266-3272,共7页
A fast explicit finite difference method (FEFDM),derived from the differential equations of one-dimensional steady pipe flow,was presented for calculation of wellhead injection pressure.Recalculation with a traditiona... A fast explicit finite difference method (FEFDM),derived from the differential equations of one-dimensional steady pipe flow,was presented for calculation of wellhead injection pressure.Recalculation with a traditional numerical method of the same equations corroborates well the reliability and rate of FEFDM.Moreover,a flow rate estimate method was developed for the project whose injection rate has not been clearly determined.A wellhead pressure regime determined by this method was successfully applied to the trial injection operations in Shihezi formation of Shenhua CCS Project,which is a good practice verification of FEFDM.At last,this method was used to evaluate the effect of friction and acceleration terms on the flow equation on the wellhead pressure.The result shows that for deep wellbore,the friction term can be omitted when flow rate is low and in a wide range of velocity the acceleration term can always be deleted.It is also shown that with flow rate increasing,the friction term can no longer be neglected. 展开更多
关键词 wellhead pressure injection pressure bottom-hole pressure fast explicit finite difference method
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Study on Reducing Injection Pressure of Low Permeability Reservoirs Characterized by High Temperature and High Salinity 被引量:4
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作者 Zhao Lin Qin Bing +2 位作者 Wu Xiongjun Wang Zenglin Jiang Jianlin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第2期44-54,共11页
In view of the problems of high injection pressure and low water injection rate in water injection wells of low permeability reservoirs featuring high temperature and high salinity,two new surfactants were synthesized... In view of the problems of high injection pressure and low water injection rate in water injection wells of low permeability reservoirs featuring high temperature and high salinity,two new surfactants were synthesized,including a quaternary ammonium surfactant and a betaine amphoteric surfactant.The composite surfactant system BYJ-1 was formed by mixing two kinds of surfactants.The minimum interfacial tension between BYJ-1 solution and the crude oil could reach 1.4×10^(-3) mN/m.The temperature resistance was up to 140℃,and the salt resistance could reach up to 120 g/L.For the low permeability core fully saturated with water phase,BYJ-1 could obviously reduce the starting pressure gradient of low permeability core.While for the core with residual oil,BYJ-1 could obviously reduce the injection pressure and improve the oil recovery.Moreover,the field test showed that BYJ-1 could effectively reduce the injection pressure of the water injection well,increase the injection volume,and increase the liquid production and oil production of the corresponding production well. 展开更多
关键词 low permeability reservoir quaternary ammonium salt betaine surfactant interfacial tension reducing injection pressure enhancing oil recovery
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Effect of nozzle geometry on pressure drop in submerged gas injection 被引量:1
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作者 XIAO Jun-bing YAN Hong-jie LIU Liu 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2068-2076,共9页
Submerged gas injection into liquid leads to complex multiphase flow, in which nozzle geometries are crucial important for the operational expenditure in terms of pressure drop. The influence of the nozzle geometry on... Submerged gas injection into liquid leads to complex multiphase flow, in which nozzle geometries are crucial important for the operational expenditure in terms of pressure drop. The influence of the nozzle geometry on pressure drop between nozzle inlet and outlet has been experimentally studied for different gas flow rates and bath depths. Nozzles with circular, gear-like and four-leaf cross-sectional shape have been studied. The results indicate that, besides the hydraulic diameter of the outlet, the orifice area and the perimeter of the nozzle tip also play significant roles. For the same superficial gas velocity, the average pressure drop from the four-leaf-shaped geometry is the least. The influence of bath depth was found negligible. A correlation for the modified Euler number considering the pressure drop is proposed depending on nozzle geometric parameter and on the modified Froude number with the hydraulic diameter of the nozzle do as characteristic length. 展开更多
关键词 submerged gas injection nozzle geometry hydraulic diameter pressure drop modified Euler number
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Clinical Analysis of Early and Mid-late Elevated Intraocular Pressure after Silicone Oil Injection 被引量:9
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作者 Lifei Wang Jingjiang Liu Tianxiang Lu 《Eye Science》 CAS 2014年第2期85-89,共5页
Purpose:.To discuss the incidence and clinical features of early and mid-late elevated intraocular pressure after pars plana vitrectomy and silicone oil injection, and to evaluate the clinical management of eyes with ... Purpose:.To discuss the incidence and clinical features of early and mid-late elevated intraocular pressure after pars plana vitrectomy and silicone oil injection, and to evaluate the clinical management of eyes with secondary glaucoma.Methods:.This was an observational consecutive case series of 691 eyes in 679 patients who were treated with pars plana vitrectomy and silicone injection...The diagnostic criteria of early elevated intraocular pressure after silicone oil injection was ≥21 mmHg two weeks after surgery, while mid-late elevated intraocular pressure was ≥21 mmHg after two weeks.The incidence and clinical management of elevated intraocular pressure were analyzed.Results: In total, 211 of 691 eyes(30.54%) developed elevated intraocular pressure two weeks after pars plana vitrecto my and silicone injection. Of the 211 eyes, 101 eyes(47.87%)had ocular inflammation, 64 eyes(30.33%) showed hyphema,35 eyes(16.59%) had silicone oil in the anterior chamber, 6eyes.(2.84%).had excess silicone oil injected,.and 5 eyes(2.37%).had rubeosis irides..Eighty three of 691 eyes(12.01%).developed elevated intraocular pressure after two weeks..Of these 83 eyes, 25 eyes(30.12%) had rubeosis irides,.16 eyes(19.27%) had issues related to topic steroid therapy,.13 eyes.(15.66%).had a papillary block,.silicone oil in the anterior chamber,10 eyes(12.05%) had a silicone emulsion,.10 eyes(12.05%).had peripheral anterior synchiae,.and 9 eyes(10.84%).had silicone oil in the anterior chamber..All eyes with elevated intraocular pressure were treated with antiglaucoma medications and surgeries.Conclusion:.The reasons for elevated intraocular pressure differed between early and mid-late after pars plana vitrectomy and silicone oil injection. The elevated intraocular pressure can be controlled effectively by immediate diagnosis and proper treatment with medicine and operation. 展开更多
关键词 中后期 硅油 眼压 临床分析 早期 注射治疗 临床管理 毫米汞柱
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Analysis and Calculation of the Flow Pressure in the Multipoint Steam Injection String of a Horizontal Well 被引量:1
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作者 Xu Xin 《International Journal of Technology Management》 2014年第9期72-74,共3页
The multipoint steam injection string of the horizontal well is a commonly used downhole component for high efficiency steam injection of the thermal recovery horizontal well. A reasonable layout of the valves to ensu... The multipoint steam injection string of the horizontal well is a commonly used downhole component for high efficiency steam injection of the thermal recovery horizontal well. A reasonable layout of the valves to ensure an even steam output of each point is still not well designed. At present, a general design method which is urgently necessary isn' t applied by each factory. According to the balance relationship of the momentum, the energy and the mass of the fluid flowing in the string, the pressure distribution equation of the fluid flowing in the multipoint steam injection string is built. On the basis of this equation, the design calculation method of the multipoint steam injection string is come up with. A specific example is given in the paper. Study shows that, with the equation built in this paper, the string can be designed with each axial valve having the same output, so that the technical demand of an even steam injection of the horizontal well section can be met. 展开更多
关键词 horizontal well multipoint steam injection pressure CALCULATION
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Elimination of Fuel Pressure Fluctuation and Multi-injection Fuel Mass Deviation of High Pressure Common-rail Fuel Injection System 被引量:8
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作者 LI Pimao ZHANG Youtong +1 位作者 LI Tieshuan XIE Lizhe 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期294-306,共13页
The influence of fuel pressure fluctuation on multi-injection fuel mass deviation has been studied a lot,but the fuel pressure fluctuation at injector inlet is still not eliminated efficiently.In this paper,a new type... The influence of fuel pressure fluctuation on multi-injection fuel mass deviation has been studied a lot,but the fuel pressure fluctuation at injector inlet is still not eliminated efficiently.In this paper,a new type of hydraulic filter consisting of a damping hole and a chamber is developed for elimination of fuel pressure fluctuation and multi-injection fuel mass deviation.Linear model of the improved high pressure common-rail system(HPCRS)including injector,the pipe connecting common-rail with injector and the hydraulic filter is built.Fuel pressure fluctuation at injector inlet,on which frequency domain analysis is conducted through fast Fourier transformation,is acquired at different target pressure and different damping hole diameter experimentally.The linear model is validated and can predict the natural frequencies of the system.Influence of damping hole diameter on fuel pressure fluctuation is analyzed qualitatively based on the linear model,and it can be inferred that an optimal diameter of the damping hole for elimination of fuel pressure fluctuation exists.Fuel pressure fluctuation and fuel mass deviation under different damping hole diameters are measured experimentally,and it is testified that the amplitude of both fuel pressure fluctuation and fuel mass deviation decreases first and then increases with the increasing of damping hole diameter.The amplitude of main injection fuel mass deviation can be reduced by 73%at most under pilot-main injection mode,and the amplitude of post injection fuel mass deviation can be reduced by 92%at most under main-post injection mode.Fuel mass of a single injection increases with the increasing of the damping hole diameter.The hydraulic filter proposed by this research can be potentially used to eliminate fuel pressure fluctuation at injector inlet and improve the stability of HPCRS fuel injection. 展开更多
关键词 high pressure common-rail system pressure fluctuation multi-injection fuel mass deviation hydraulic filter
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Paracentesis following intravitreal drug injections in maintaining physiologic ocular perfusion pressure
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作者 Austin Bach Artur Filipowic +2 位作者 Aaron S. Gold Azeema Latiff Timothy G. Murray 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第12期1925-1927,共3页
A retrospective analysis was performed of patients who received a paracentesis immediately following an intravitreal injection of bevacizumab or triamcinolone acetonide.These patients were previously diagnosed as havi... A retrospective analysis was performed of patients who received a paracentesis immediately following an intravitreal injection of bevacizumab or triamcinolone acetonide.These patients were previously diagnosed as having glaucoma,ocular hypertension,or had responded previously with sustained elevated intraocular pressure.Of 1661 procedures were performed.Totally 219(13%) of the injections were on phakic patients.A median(SD) of 210 μL(40 μL) of aqueous was removed during each paracentesis.There were no reported incidences of any complications.We propose performing a paracentesis immediately following intravitreal injections for patients at risk for ocular hypertension,glaucoma,and retinal vein or artery occlusion. 展开更多
关键词 anterior chamber paracentesis intravitreal injection intraocular pressure ocular perfusion pressure
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Acne Treated by point Injection of One's Own Blood Concerted with Ear-Acupuncture-Pressure: Observation on 70 Cases
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作者 Wang Libo Jiang Xinhua Niu Chuiju(Central Hospital of Forestry of Mudanjiang,Heilongjang 157011 ) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期297-298,共2页
AcneTreatedbyPointInjectionofOne'sOwnBloodConcertedwithEar-Acupuncture-Pressure:Observationon70Cases¥WangLib... AcneTreatedbyPointInjectionofOne'sOwnBloodConcertedwithEar-Acupuncture-Pressure:Observationon70Cases¥WangLibo;JiangXinhua;Niu... 展开更多
关键词 Observation ACUPUNCTURE injection Concerted EAR ACNE CASES One OWN pressure
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Generation and propagation characteristics of fluctuation pressure in hydraulic fracturing with unstable fluid-injection
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作者 ZHU Ge DONG Shi-min +1 位作者 JIA He-tong DONG Zi-long 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期186-196,共11页
Different from the stable injection mode of conventional hydraulic fracturing,unstable fluid-injection can bring significant dynamic effect by using variable injection flow rate,which is beneficial to improve the frac... Different from the stable injection mode of conventional hydraulic fracturing,unstable fluid-injection can bring significant dynamic effect by using variable injection flow rate,which is beneficial to improve the fracturing effect.Obviously,the propagation process of fracturing fluid along the pipe string is crucial.In this paper,the fluid transient dynamics model in the pipe string was established,considering the boundary conditions of variable injection flow rate and reservoir seepage,and the unsteady friction was also taken into account.The above model was solved by characteristics and finite difference method respectively.Furthermore,the influences of geological parameters and fluid injection schemes on fluctuating pressure were also analyzed.The results show that unstable fluid-injection can cause noticeable fluctuation of fracturing fluid in the pipe string.Simultaneously,there is attenuation during the propagation of pressure fluctuation.The variation frequency of unstable fluid-injection and well depth have significant effects on pressure fluctuation amplitude at the bottom of the well.This research is conducive to understanding the mechanism of unstable fluid-injection hydraulic fracturing and providing guidance for the design of fluid-injection scheme. 展开更多
关键词 hydraulic fracturing unstable injection transient flow fluctuation pressure SEEPAGE
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