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Characteristics of Abnormal Pressure Systems and Their Responses of Fluid in Huatugou Oil Field,Qaidam Basin 被引量:3
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作者 CHEN Xiaozhi XU Hao +4 位作者 TANG Dazhen ZHANG Junfeng HU Xiaolan TAO Shu CAI Yidong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期939-950,共12页
Based on the comprehensive study of core samples, well testing data, and reservoir fluid properties, the construction and the distribution of the abnormal pressure systems of the Huatugou oil field in Qaidam Basin are... Based on the comprehensive study of core samples, well testing data, and reservoir fluid properties, the construction and the distribution of the abnormal pressure systems of the Huatugou oil field in Qaidam Basin are discussed. The correlation between the pressure systems and hydrocarbon accumulation is addressed by analyzing the corresponding fluid characteristics. The results show that the Huatugou oil field as a whole has low formation pressure and low fluid energy; therefore, the hydrocarbons are hard to migrate, which facilitates the forming of primary reservoirs. The study reservoirs, located at the Xiayoushashan Formation (N1/2) and the Shangganchaigou Formation (N1) are relatively shallow and have medium porosity and low permeability. They are abnormal low-pressure reservoirs with an average formation pressure coefficient of 0.61 and 0.72 respectively. According to the pressure coefficient and geothermal anomaly, the N1 and N1/2 Formations belong to two independent temperature-pressure systems, and the former has slightly higher energy. The low-pressure compartments consist of a distal bar as the main body, prodelta mud as the top boundary, and shore and shallow lake mud or algal mound as the bottom boundary. They are vertically overlapped and horizontally paralleled. The formation water is abundant in the Cl^- ion and can be categorized as CaCl2 type with high safinity, which indicates that the abnormal low-pressure compartments are in good sealing condition and beneficial for oil and gas accumulation and preservation. 展开更多
关键词 abnormal pressure system low-pressure compartment fluid characteristics Huatugou oil field Qaidam basin
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Formation of overpressure system and its relationship with the distribution of large gas fields in typical foreland basins in central and western China 被引量:3
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作者 LI Wei CHEN Zhuxin +3 位作者 HUANG Pinghui YU Zhichao MIN Lei LU Xuesong 《Petroleum Exploration and Development》 CSCD 2021年第3期625-640,共16页
Based on the data of measured formation pressure, drilling fluid density of key exploration wells and calculated pressure by well logging, combined with the analysis of natural gas geological conditions, the character... Based on the data of measured formation pressure, drilling fluid density of key exploration wells and calculated pressure by well logging, combined with the analysis of natural gas geological conditions, the characteristics and formation mechanisms of formation fluid overpressure systems in different foreland basins and the relationship between overpressure systems and large-scale gas accumulation are discussed.(1) The formation mechanisms of formation overpressure in different foreland basins are different. The formation mechanism of overpressure in the Kuqa foreland basin is mainly the overpressure sealing of plastic salt gypsum layer and hydrocarbon generation pressurization in deep–ultra-deep layers, that in the southern Junggar foreland basin is mainly hydrocarbon generation pressurization and under-compaction sealing, and that in the western Sichuan foreland basin is mainly hydrocarbon generation pressurization and paleo-fluid overpressure residual.(2) There are three common characteristics in foreland basins, i.e. superimposed development of multi-type overpressure and multi-layer overpressure, strong–extremely strong overpressure developed in a closed foreland thrust belt, and strong–extremely strong overpressure developed in a deep foreland uplift area.(3) There are four regional overpressure sealing and storage mechanisms, which play an important role in controlling large gas fields, such as the overpressure of plastic salt gypsum layer, the overpressure formed by hydrocarbon generation pressurization, the residual overpressure after Himalayan uplift and denudation, and the under-compaction overpressure.(4) Regional overpressure is an important guarantee for forming large gas fields, the sufficient gas source, large-scale reservoir and trap development in overpressure system are the basic conditions for forming large gas fields, and the overpressure system is conducive to forming deep to ultra-deep large gas fields. 展开更多
关键词 central and western China foreland basin overpressure system large gas field hydrocarbon generation pressurization under-compaction salt gypsum layer overpressure sealing overpressure residual
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On the Relationship between Climatic Variables and Pressure Systems over Saudi Arabia in the Winter Season
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作者 H.M.HASANEAN H.Abdel BASSET M.A.A.HUSSEIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第5期690-703,共14页
The synoptic circulation over Saudi Arabia is complicated and frequently governed by the effect of large-scale pressure systems. In this work, we used NCEP–NCAR global data to illustrate the relationship between clim... The synoptic circulation over Saudi Arabia is complicated and frequently governed by the effect of large-scale pressure systems. In this work, we used NCEP–NCAR global data to illustrate the relationship between climatic variables and the main pressure systems that affect the weather and climate of Saudi Arabia, and also to investigate the influence of these pressure systems on surface air temperature(SAT) and rainfall over the region in the winter season. It was found that there are two primary patterns of pressure that influence the weather and climate of Saudi Arabia. The first occurs in cases of a strengthening Subtropical High(Sub H), a weakening Siberian High(Sib H), a deepening of the Icelandic Low(Ice L), or a weakening of the Sudanese Low(Sud L). During this pattern, the Sub H combines with the Sib H and an obvious increase of sea level pressure(SLP) occurs over southern European, the Mediterranean, North Africa, and the Middle East. This belt of high pressure prevents interaction between midlatitude and extratropical systems, which leads to a decrease in the SAT,relative humidity(RH) and rainfall over Saudi Arabia. The second pattern occurs in association with a weakening of the Sub H, a strengthening of the Sib H, a weakening of the Ice L, or a deepening of the Sud L. The pattern arising in this case leads to an interaction between two different air masses: the first(cold moist) air mass is associated with the Mediterranean depression travelling from west to east, while the second(warm moist) air mass is associated with the northward oscillation of the Sud L and its inverted V-shape trough. The interaction between these two air masses increases the SAT, RH and the probability of rainfall over Saudi Arabia, especially over the northwest and northeast regions. 展开更多
关键词 climatic variables pressure system surface air temperature RAINFALL relative humidity Saudi Arabia
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Comparison of walking quality variables between incomplete spinal cord injury patients and healthy subjects by using a footscan plantar pressure system 被引量:4
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作者 Xiang-Nan Yuan Wei-Di Liang +4 位作者 Feng-Hua Zhou Han-Ting Li Li-Xin Zhang Zhi-Qiang Zhang Jian-Jun Li 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期354-360,共7页
The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can ... The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury(SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University(approval No. 2015 PS54 J) on August 13, 2015. This trial was registered in the ISRCTN Registry(ISRCTN42544587) on August 22, 2018. Protocol version: 1.0. 展开更多
关键词 nerve REGENERATION spinal cord injury WALKING gait QUALITY PLANTAR pressure system PLANTAR pressure distribution speed PLANTAR pressure impulse contact area symmetry index neural REGENERATION
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Management of Complex Wounds with Dermal Substitute Assisted by a Negative Pressure System
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作者 Cuahutémoc Márquez Espriella Ruiz Garza Jorge Gerardo +18 位作者 Barbosa Villarreal Fernando Dávila Díaz Rodrigo Cuervo Vergara Marco Antonio Campollo López Ana Priscila Gutierrez Alvarez Mauricio Chama Naranjo Alfredo García Corral Jesús Ricardo Pérez Benítez Omar Alberto Pulido López Ricardo Alberto Jaimes Duran Edwing Michel Garibaldi Bernot Mauro Cortes Aguilar Carlos Manuel García Córdova Carlos Emiliano Camacho Rodriguez Hayah Camacho Rodriguez Hayah Martinez Villalobos Claudia Nallely Ochoa Contreras Erick Cesar Randall Cruz Soto Herrera Lozano Luis Arturo 《Modern Plastic Surgery》 2023年第4期95-105,共11页
Introduction: The standard treatment for complex wound care is autografting. The advent of dermal substitutes has provided a novel tool for the preparation of the bed to be grafted. However, most types of dermal matri... Introduction: The standard treatment for complex wound care is autografting. The advent of dermal substitutes has provided a novel tool for the preparation of the bed to be grafted. However, most types of dermal matrices require the application of a skin graft a second time. Currently, other strategies have been developed to improve the vascularization process, such as negative pressure wound therapy (NPWT), which has been reported to reduce the time required for vascular growth and dermal matrix integration and thus achieve a shorter waiting period for autologous graft application. The present study aims to evaluate the effectiveness and safety of dermal matrix management associated with NPWT in the treatment of complex wounds. Methods: Seven patients with a diagnosis of complex wounds were enrolled in this study between July 1, 2015, and June 31, 2016. After debridement and having an adequate wound bed, patients who met the criteria for the application of combined therapy were treated with dermal substitutes and a negative pressure system. The percentage of graft integration into the wound bed, complications, length of hospital stay, and duration of therapy were analyzed. Results: The mean age was 42.5 ± 16 (39 - 54) years old;three women and four men were included in the study. The approximate size of skin loss was 120.7 ± 75 cm<sup>2</sup> (25 - 250 cm<sup>2</sup>). The combined therapy of dermal matrix plus NPWT was instituted in all cases for a period of 14 days. There were no complications, with 100% graft integration in 6 of 7 cases. Patients were discharged after a mean hospital stay of 5.4 days. Conclusions: This study demonstrates that the utilization of combined dermal matrix plus NPWT therapy can be performed safely and effectively in patients with complex wounds with low complication rates and a short hospital stay. 展开更多
关键词 Negative pressure Wound Therapy Complex Wound Dermal Matrix Wound Therapy
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The effectiveness of physical activity interventions on blood pressure in children and adolescents:A systematic review and network meta-analysis
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作者 Mohamed A.Hassan Wanjiang Zhou +2 位作者 Mingyi Ye Hui He Zan Gao 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期699-708,共10页
Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(P... Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(PA)intervention.This systematic review and network meta-analysis(NMA)aimed to evaluate the available evidence on the effectiveness of various PA interventions for reducing BP and to determine their hierarchy based on their impact on BP.Methods:A search of PubMed,SPORTDiscus,PsycINFO,Web of Science,CINAHL,Cochrane,and Eric databases was conducted up to December 2022 for this systematic review and NMA.Randomized controlled trials and quasi-experimental studies targeting healthy children and adolescents aged 6-12 years old were included in this study.Only studies that compared controlled and intervention groups using PA or exercise as the major influence were included.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.Three independent investigators performed the literature screening,data extraction,and risk of bias assessment.We used Bayesian arm-based NMA to synthesize the data.The primary outcomes were systolic BP and diastolic BP.We calculated the mean differences(MDs)in systolic BP and diastolic BP before and after treatment.Mean treatment differences were estimated using NMA and random-effect models.Results:We synthesized 27 studies involving 15,220 children and adolescents.PA combined with nutrition and behavior change was the most effective intervention for reducing both systolic BP and diastolic BP(MD=-8.64,95%credible interval(95%CI):-11.44 to-5.84;MD=-6.75,95%CI:-10.44 to-3.11),followed by interventions with multiple components(MD=-1.39,95%CI:-1.94 to-0.84;MD=-2.54,95%CI:-4.89 to-0.29).Conclusion:Our findings suggest that PA interventions incorporating nutrition and behavior change,followed by interventions with multiple components,are most effective for reducing both systolic BP and diastolic BP in children and adolescents. 展开更多
关键词 CHILDREN Diastolic blood pressure Physical activity Systolic blood pressure
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Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system
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作者 Nai-Liang Li Bin Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1305-1319,共15页
Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to ... Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop. 展开更多
关键词 Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging CORRELATION
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Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method
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作者 M.Hajipour G.R.Ansarifar 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期145-154,共10页
Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor... Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual reactor.In an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the nonlinearities.In this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled simultaneously.In an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power maneuvering.Reactor point kinetics equations with three groups of delayed neutrons were used in the simulation.Higher-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous studies.The controlled parameters were reactor power,steam temperature,and pressure.Notably,for these parameters,the PI controller had certain instabilities in the presence of disturbances.The classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering phenomenon.HOSMC was highly accurate and stable and had a small computational cost.In reality,it followed the desired values without oscillations and chattering. 展开更多
关键词 Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model
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Ethics of Human Resources Management in the Cameroonian Health System, Medical Nomadism and the Ineffectiveness of the Fight against High Blood Pressure
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作者 Jean Ndibi Abanda Anicet Onana Akoa +2 位作者 Désiré Tchoffo Ulrich Dama Pierre Yassa Yoniene 《Health》 2024年第1期9-21,共13页
Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of sk... Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of skills on both qualitative and quantitative levels is one of the essential functions of a health system. To better implement policies of fight against High Blood Pressure (HBP) and other chronic diseases, it is important to establish strategies to retain health personnel. This loyalty requires favorable working conditions and consideration of the contribution-reward couple. Good working conditions are likely to reduce the phenomenon of medical nomadism;conversely, poor HR management can contribute to their exodus towards exotic “green pastures”, thus leading to an additional crisis in the Cameroonian health system. The fight against HBP is a complex, multifaceted and multifactorial reality that requires appropriate management model for all types of resources mainly HR. The main objective of this research is to show the impact of poor management of human resources in Cameroon health system on medical nomadism and the ineffectiveness of the fight against High Blood Pressure. Method: A cross-sectional descriptive survey among five hundred (500) health facilities in the center region of Cameroon has been conducted. A stratified probabilistic technique has been used, and the number of health facilities to be surveyed has been determined using the “sample size estimation table” of Depelteau. The physical questionnaires have been printed and then distributed to data collectors. After data collection, the latter were grouped during processing in Excel sheets. The Chi-square test was used for data with a qualitative value and that of Kolmogorov-Sminorf for data with a quantitative value to assess the normality and reliability of data. The Crochach’s Alpha reliability test allowed us to have a summary of the means and variances and then to search for intragroup correlations between variables. Descriptive analysis was possible with the XLSTAT 2016 software. Results: 43.60% of Health Facilities (HF) managers were unqualified. 82.20% of HF managers have staff in a situation of professional insecurity. They are mainly contractual (49.00), decision-making agents (24.40%), casual agents (08.80). The proportion of unstable personnel is average of 22.00% and very unstable, 12.00%. 展开更多
关键词 ETHICS Human Resources Management Cameroonian Health system Medical Nomadism Ineffectiveness High Blood pressure
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Development of a Pipeline Pulsating Pressure Excitation Device and System
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作者 Yong Su Wu-qi Gong 《风机技术》 2024年第5期63-72,共10页
The high turbulence of unstable combustion in the working process of liquid rocket engine will cause periodic pressure pulsation.Therefore,a pressure pulsation device that is easy to reuse,broadband,suited for poisono... The high turbulence of unstable combustion in the working process of liquid rocket engine will cause periodic pressure pulsation.Therefore,a pressure pulsation device that is easy to reuse,broadband,suited for poisonous media,and high pressure is designed and produced.Numerical and experimental studies show that the pulsator produces stable pressure waveforms at different flow rates,pressures,and frequencies,while the pressure waveform amplitude at the excitation frequency is larger.The pressure waveform amplitude increases exponentially with the flow rate and with smaller gaps and linear pressure increasing.The pressure waveform amplitude varies greatly at different frequencies along the pipeline.As the frequency increases,the pressure waveform amplitude of the excitation increases first and then decreases.The pressure waveform amplitude at low frequencies changes little along the pipeline.The pressure waveform amplitude at medium frequencies readily couples to the pipeline flow field and increases its value.The pressure waveform amplitude at high frequencies attenuates along the pipeline,where attenuation increases with frequency.The ability of the pulsator to provide stable excitation and high pressure is verified through normal and high pressure testsindifferentpipelinesystems. 展开更多
关键词 Pulsator pressure FLUCTUATION High-pressure Dynamic Characteristic Rocket Engine
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φ-pH diagram of V-Ti-H_2O system during pressure acid leaching of converter slag containing vanadium and titanium 被引量:4
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作者 牟望重 张廷安 +2 位作者 豆志河 吕国志 刘燕 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2078-2086,共9页
To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures rangi... To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures ranging from 60 to 200 ℃ was obtained by recently published critically assessed standard Gibbs energies and activity coefficients of various species. When pH2, stable regions of V3+, VO2+ and VO2+ exist in the stable region of TiO2. The pH values of stable regions of vanadium and titanium decrease and redox potentials become more positive with the temperature increasing. Vanadium and titanium could be separated by one-step leaching based on thermodynamics. The experiment results of pressure acid leaching of converter slag show that leaching rates of vanadium and titanium are 96.87% and 8.76% respectively, at 140 ℃ of temperature, 0.5 MPa of oxygen partial pressure, 0.055-0.075mm of particle size, 15:1 of liquid to solid ratio, 120 min of leaching time, 500 r/min of stirring speed and 200 g/L of initial acid concentration. Vanadium and titanium could be selectively separated in the pressure acid leaching process, and the experiment result is in agreement with thermodynamic calculation result. 展开更多
关键词 φ-pH diagram V-Ti-H2O system pressure acid leaching converter slag VANADIUM titanium
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Effect of Implanted Chip System on Blood Pressure Regulation in Rabbits 被引量:1
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作者 高兴亚 王汉军 +4 位作者 朱国庆 郭瑞 张枫 张颖 陆祖宏 《Journal of Nanjing Medical University》 2004年第6期279-282,共4页
Objective: To evaluate the efficiency of an implanted chip system on blood pressure regulation. Methods: The mean arterial pressure (MAP) and heart rate (HR) were recorded in anesthetized rabbits. Based on the set poi... Objective: To evaluate the efficiency of an implanted chip system on blood pressure regulation. Methods: The mean arterial pressure (MAP) and heart rate (HR) were recorded in anesthetized rabbits. Based on the set point theory, an implanted chip system was designed to regulate the blood pressure by stimulating the aortic depressor nerve (ADN) according to the feedback of blood pressure. The blood pressure regulation induced by the implanted chip system was carried out twice (lasted for 15 min and 60 min respectively) and the change of MAP and HR during the regulation was compared with the control. Results: There was a significant decrease of MAP during the first regulation ([-32.0 ± 6.6] mmHg) and second regulation ([-27.4 ± 6.2] mmHg) compared with the control (P<0.01). The HR was also significantly decreased during regulation compared with the control. Both MAP and HR returned to the baseline immediately without rebound after the regulation ceased. Conclusion: The implanted chip system can regulate the blood pressure successfully and keep the blood pressure in a lower constant level without adaptation. 展开更多
关键词 implanted chip blood pressure set point HYPERTENSION
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Wireless distributed test system based on transient pressure signal detection and recognition 被引量:2
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作者 贾振华 王文廉 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期18-23,共6页
During the test on transient pressure signal in explosion field,false trigger caused by field interference can lead to test failure.To improve the stability of test system,a signal detection and recognition technology... During the test on transient pressure signal in explosion field,false trigger caused by field interference can lead to test failure.To improve the stability of test system,a signal detection and recognition technology is proposed for transient pressure test system.In the process of signal acquisition,firstly,electrical levels are monitored in real time to find effective abrupt changes and mark them;then the effective data segments are detecdted totected;thus the effective signals can be acquired in turn finally.The experimental results show that the shock wave signal can be collected effectively and the reliability of the test system can be improved after removal of interferences. 展开更多
关键词 signal recognition shock wave signal transient pressure test
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Vapor pressure measurement of lead and lead chlorides in FeO_T-CaO-SiO_2-Al_2O_3 system 被引量:1
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作者 张延玲 Eiki KASAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2772-2780,共9页
Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with in... Vapor pressure of lead and lead chlorides from FeOT?CaO?SiO2?Al2O3 slag system was measured by using Knudsen effusion method. The results suggest that the vapor pressures of lead and lead chlorides increase with increasing temperature. For the slag systems without chlorine, the logarithm of vapor pressure (lnp) shows highly linear dependency on the reciprocal of temperature (1/T), and higher vapor pressure is observed in the condition where more metallic lead vapor is formed. In this case, the vapor pressure of lead increases with increasing slag basicity (w(CaO)/w(SiO2)), increasing FeO content andw(Fe2+)/w(Fe3+) ratio. For the case of slag system with chlorine addition, the total pressures of PbCl2 and PbCl increase with decreasing basicity and FeO content of slag. 展开更多
关键词 金属Pb vapor pressure Knudsen effusion method metallic Pb lead chlorides smelting process
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The Effects of Strong Ageostrophic Outflows on the Formation of Surface Mesoscale Pressure Systems in Squall Lines 被引量:1
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作者 姜勇强 王元 《Acta meteorologica Sinica》 SCIE 2010年第2期225-238,共14页
Based on the previous study of the streamline field triggered by singularities in a two-dimensional potential flow,the wind field caused by vorticity lines in an incompressible flow is deduced in this paper.The result... Based on the previous study of the streamline field triggered by singularities in a two-dimensional potential flow,the wind field caused by vorticity lines in an incompressible flow is deduced in this paper.The result shows an elliptic cyclonic(anticyclonic) circulation in association with a positive(negative) vorticity line.By use of the shallow-water model,the flow fields are simulated in a weak wind background under the influence of mesoscale vorticity lines.In the case of two vorticity line,one positive and the other negative,a mesoscale vortex couplet forms in the flow.When three vorticity lines are considered,three mesoscale circulations develop,and a mesohigh and two mesolows similar to the thunderstorm high,wake low and pre-squall mesolow of a mature squall line are produced.Theoretical analysis and numerical simulations show that the formation of the surface mesoscale pressure systems in squall lines may be partly attributed to the dynamical effects of the ageostrophic outflows.The strong downdrafts under the thundercloud base of the squall line lead to surface ageostrophic outflows,and produce positive-negative-positive arranged vertical vorticity bands(VBs) along the direction normal to the squall line,then the mesoscale circulations develop and mesoscale pressure systems form or strengthen during the geostrophic adjustment.By use of the scale separation method,this dynamic mechanism is confirmed by a case study of a severe storm passing over eastern China on 17 June 1974. 展开更多
关键词 squall line ageostrophic wind vorticity line mesoscale pressure system
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Development of Energy-storing High Pressure Spray Cooling System
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作者 林家彬 周忠凯 +7 位作者 秦竹 李辉 唐玉新 顾洪如 杨杰 汤赤 陈俊 余刚 《Agricultural Science & Technology》 CAS 2015年第1期167-171,共5页
The greenhouse has been increasingly used in the breeding industry. However, the high temperature inside the greenhouse in summer has not been effectively addressed. The spray cooling system sprays tiny droplets into ... The greenhouse has been increasingly used in the breeding industry. However, the high temperature inside the greenhouse in summer has not been effectively addressed. The spray cooling system sprays tiny droplets into the air. Thus the water molecules will be vaporized, absorbing heat and reducing ambient temperature. It is the only cooling method that can be used to cool the uneasily-sealed flexible greenhouse. We developed an energy-storing high pressure spray cooling system. The ordinary water pump is used as the source of high-pressure water. The partial kinetic energy is stored in the energy-storing tubes. When the water pump is stopped, the energy produced by releasing the compressed air can still be used to maintain the spray. And thus the use-cost and systematic wear would be reduced. The cooling system only requires 1 kilowatt hour of power per day. It has been widely used in summer to cool the breeding sheds. After a recent continuous improvement, its functions have been extended to disinfection, removing dust, humidifying and immunizing animals. In addition, it can also be used for the cooling and humidifying of squares, venues and streets in summer. The energy-storing high pressure spray cooling system has a broad application prospect. 展开更多
关键词 Energy-storing High pressure spray Spray cooling Energy-storing system Facility agriculture
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Design and implementation of configurable parameters test system for transient pressure measurement
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作者 解亚妮 贾振华 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期123-127,共5页
For the shock wave overpressure signal measurement of explosion field, the type and equivalent of the ammunition as well as the distance from test nodes to ground zero have a great influence on the characteristics of ... For the shock wave overpressure signal measurement of explosion field, the type and equivalent of the ammunition as well as the distance from test nodes to ground zero have a great influence on the characteristics of shock wave signal. To ensure that shock wave signal with different characteristic parameters can be collected completely in the test of shooting range, a tran- sient pressure signal storage system with configurable parameters is presented. In order to meet the requirements of different test nodes, the system can set parameters of all test nodes by wireless communication in explosion field. The feasibility and re- liability of the system are fully verified through transient pressure measurement in explosion field. 展开更多
关键词 transient pressure shock wave signal test system configurable parameters
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Design and theoretical analysis of test system for propellants' gas pressure in warhead
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作者 边晶晶 武震 《Journal of Measurement Science and Instrumentation》 CAS 2014年第1期10-14,共5页
Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 i... Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system's modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained. 展开更多
关键词 warhead dispersion center tube explosion dispersion gas pressure storage test and measurement low power consumption
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BLOCKING EFFECT OF HIGH PRESSURE SYSTEM ON THE FORMATION OF EXTRA-INTENSE HEAVY RAIN
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作者 章淹 《Acta meteorologica Sinica》 SCIE 1989年第4期458-470,共13页
Commonly the centre of an intense heavy rain occurs in a very limited area,but for the three extra- intense heavy rains of the present study,63-8 in North China,75-8 in central China and 77-8 in the desert region of I... Commonly the centre of an intense heavy rain occurs in a very limited area,but for the three extra- intense heavy rains of the present study,63-8 in North China,75-8 in central China and 77-8 in the desert region of Inner Mongolia,which all appeared under the environments of“Western Low and Eastern Blocking” (EB)pattern.From this study,the following effects of the EB are found:(1)It affects the precipitation systems staggering in a local place and/or changes the trajectories of low votices and urges them into the same raining areas intermittently.(2)It transports water vapour into raining areas.The air flows by the west side of EB produce strong cyclonic vorticity behind EB frequently,which transports water vapour and forms mesoscale precipitation systems more favourably than the low level jets.(3)Air flows behind EB con- jugate with adequate topographic relief,which enhances the precipitation and makes the raining areas over- lapped.So that extra-intense heavy rains could occur in higher latitudes of semi-aird areas,and occasionally even in the desert region of North China. Such extra-intense heavy rains could not be explained by static local humidity and temperature only. This is also a principal discrimination between the prolonged extra-intense heavy rain and the short-range convective precipitation and/or the common precipitation. 展开更多
关键词 BLOCKING EFFECT OF HIGH pressure system ON THE FORMATION OF EXTRA-INTENSE HEAVY RAIN PMP
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Reliability Design for Impact Vibration of Hydraulic Pressure Pipeline Systems 被引量:17
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作者 ZHANG Tianxiao LIU Xinhui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期1050-1055,共6页
The research of reliability design for impact vibration of hydraulic pressure pipeline systems is still in the primary stage,and the research of quantitative reliability of hydraulic components and system is still inc... The research of reliability design for impact vibration of hydraulic pressure pipeline systems is still in the primary stage,and the research of quantitative reliability of hydraulic components and system is still incomplete.On the condition of having obtained the numerical characteristics of basic random parameters,several techniques and methods including the probability statistical theory,hydraulic technique and stochastic perturbation method are employed to carry out the reliability design for impact vibration of the hydraulic pressure system.Considering the instantaneous pressure pulse of hydraulic impact in pipeline,the reliability analysis model of hydraulic pipeline system is established,and the reliability-based optimization design method is presented.The proposed method can reflect the inherent reliability of hydraulic pipe system exactly,and the desired result is obtained.The reliability design of hydraulic pipeline system is achieved by computer programs and the reliability design information of hydraulic pipeline system is obtained.This research proposes a reliability design method,which can solve the problem of the reliability-based optimization design for the hydraulic pressure system with impact vibration practically and effectively,and enhance the quantitative research on the reliability design of hydraulic pipeline system.The proposed method has generality for the reliability optimization design of hydraulic pipeline system. 展开更多
关键词 hydraulic pressure impact vibration systems probability perturbation method reliability design
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