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Experimental Study and Simulation Principles of An Oil-Gas Multiphase Transportation System 被引量:3
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作者 吴应湘 郑之初 +2 位作者 李东晖 劳力云 马艺馨 《China Ocean Engineering》 SCIE EI 2000年第1期33-44,共12页
Presented is an experimental study on the performance of an oil-gas multiphase transportation system, especially on the multiphase flow patterns, multiphase pumping and multiphase metering of the system. A dynamic sim... Presented is an experimental study on the performance of an oil-gas multiphase transportation system, especially on the multiphase flow patterns, multiphase pumping and multiphase metering of the system. A dynamic simulation analysis is conducted to deduce simulation parameters of the system and similarity criteria under simplified conditions are obtained. The reliability and feasibility of two-phase flow experiment with oil and natural gas simulated by water and air are discussed by using the similarity criteria. 展开更多
关键词 multiphase flow similarity criteria simulation principle oil-gas multiphase transportation
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Wave Effect on the Ocean Circulations Through Mass Transport and Wave-Induced Pumping 被引量:3
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作者 BI Fan WU Kejian 《Journal of Ocean University of China》 SCIE CAS 2014年第2期175-182,共8页
The wave Coriolis-Stokes-Force-modified ocean momentum equations are reviewed in this paper and the wave Stokes transport is pointed out to be part of the ocean circulations. Using the European Centre for Medium-Range... The wave Coriolis-Stokes-Force-modified ocean momentum equations are reviewed in this paper and the wave Stokes transport is pointed out to be part of the ocean circulations. Using the European Centre for Medium-Range Weather Forecasts 40-year reanalysis data(ERA-40 data) and the Simple Ocean Data Assimilation(SODA) version 2.2.4 data, the magnitude of this transport is compared with that of wind-driven Sverdrup transport and a 5-to-10-precent contribution by the wave Stokes transport is found. Both transports are stronger in boreal winter than in summers. The wave effect can be either contribution or cancellation in different seasons. Examination with Kuroshio transport verifies similar seasonal variations. The clarification of the efficient wave boundary condition helps to understand the role of waves in mass transport. It acts as surface wind stress and can be functional down to the bottom of the ageostrophic layer. The pumping velocities resulting from wave-induced stress are zonally distributed and are significant in relatively high latitudes. Further work will focus on the model performance of the wave-stress-changed-boundary and the role of swells in the eastern part of the oceans. 展开更多
关键词 海洋环流 运输 大众 季节性变化 流通 数值天气预报 波浪作用 再分析资料
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Role of Ekman Transport Versus Ekman Pumping in Driving Summer Upwelling in the South China Sea 被引量:3
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作者 WANG Dakui WANG Hui +2 位作者 LI Ming LIU Guimei WU Xiangyu 《Journal of Ocean University of China》 SCIE CAS 2013年第3期355-365,共11页
Relative roles of Ekman transport and Ekman pumping in driving summer upwelling in the South China Sea(SCS) are examined using QuikSCAT scatterometer wind data.The major upwelling regions in the SCS are the coastal re... Relative roles of Ekman transport and Ekman pumping in driving summer upwelling in the South China Sea(SCS) are examined using QuikSCAT scatterometer wind data.The major upwelling regions in the SCS are the coastal regions east and southeast of Vietnam(UESEV),east and southeast of Hainan Island(UESEH),and southeast of Guangdong province(USEG).It is shown that the Ekman transport due to alongshore winds and Ekman pumping due to offshore wind stress curl play different roles in the three upwelling systems.In UESEV,Ekman pumping and Ekman transport are equally important in generating upwelling.The Ekman transport increases linearly from 0.49 Sv in May to 1.23 Sv in August,while the Ekman pumping increases from 0.36 to 1.22 Sv during the same period.In UESEH,the mean estimates of Ekman transport and Ekman pumping are 0.14 and 0.07 Sv,respectively,indicating that 33% of the total wind-driven upwelling is due to Ekman pumping.In USEG,the mean Ekman transport is 0.041 Sv with the peak occurring in July,while Ekman pumping is much smaller(0.003 on average),indicating that the upwelling in this area is primarily driven by Ekman transport.In the summers of 2003 and 2007 following El Ni o-Southern Oscillation(ENSO) events,both Ekman transport and Ekman pumping decrease in UESEV due to the abnormally weak southwest monsoon.During the same events,however,Ekman transport is slightly enhanced and Ekman pumping is weakened in UESEH and USEG. 展开更多
关键词 交通运输 中国南海 EKMAN抽吸 海上 夏季 驱动 南海地区 ENSO
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Pump-lockage ore transportation system for deep sea flexible mining system 被引量:4
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作者 徐海良 尹平伟 +1 位作者 徐绍军 杨放琼 《Journal of Central South University of Technology》 EI 2008年第4期540-544,共5页
Based on characteristics of deep sea flexible mining system,a new pump-lockage ore transportation system was designed.According to Bernoulli equation and two-phase hydrodynamics theory,parameters of the new system wer... Based on characteristics of deep sea flexible mining system,a new pump-lockage ore transportation system was designed.According to Bernoulli equation and two-phase hydrodynamics theory,parameters of the new system were obtained and four ore transportation systems were analyzed.The results indicate that the pump head of 1 000 m mining system is 100-150 m and that of 5 000 m mining system is 660-750 m.In addition,based on similarity theory,a model of the new transportation system was made,which can simulate more than 5 000 m actual ore transportation system.So both theory and experiment prove that the new pump-lockage ore transportation system is an ideal design for deep sea flexible mining system. 展开更多
关键词 水闸 矿石运输系统 开采技术 船闸
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可见光抗菌的单向导湿自泵织物
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作者 王健 时连鑫 葛介超 《发光学报》 EI CAS CSCD 北大核心 2024年第5期853-860,共8页
具有湿度管理和抑菌性能的功能织物可以有效提高穿着舒适度。现有方法往往通过在亲水织物表面物理浸涂抗菌剂,虽然可起到短效抑菌作用,但会导致抗菌剂大量突释,引起皮肤不适,抗菌能力快速减弱。本文利用静电纺丝方法制备了一种掺杂可见... 具有湿度管理和抑菌性能的功能织物可以有效提高穿着舒适度。现有方法往往通过在亲水织物表面物理浸涂抗菌剂,虽然可起到短效抑菌作用,但会导致抗菌剂大量突释,引起皮肤不适,抗菌能力快速减弱。本文利用静电纺丝方法制备了一种掺杂可见光激发抗菌光敏剂的自泵织物(Self-pumping textile,SPT),实现了汗液的单向移除同时高效抗菌。自泵织物由疏水的聚偏二氟乙烯-六氟丙烯(PVDF-HFP)纤维和亲水的碱水解醋酸纤维素(CA)纤维组成,其中亲水纤维中掺杂了具有高活性氧产生能力的聚噻吩(PT2)光敏剂。在接触角导液模型中,我们证实了导液时间随疏水层厚度增加而延长,当疏水层电纺时间为60 s时,水分可以在10 s内从疏水层单向导出到亲水层。使用功率为25 mW/cm^(2)的氙灯光模拟日常太阳光进行抗菌,结果表明,10 min可以杀灭95%以上的金黄色葡萄球菌和大肠杆菌。本工作为功能性织物的设计提供了一种新的思路。 展开更多
关键词 自泵织物 单向导湿 可见光抗菌 光动力
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长江口南槽悬沙纵向和横向输运过程与机制研究
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作者 李致尚 李占海 +4 位作者 李霞 杨海飞 施韩臻 卢婷 汪亚平 《海洋通报》 CAS CSCD 北大核心 2024年第1期1-20,共20页
河口悬沙输运对于最大浑浊带形成发育、地貌演变、港口航道安全、水质以及生态系统健康至关重要。本文基于2017年洪季长江口南槽拦门沙海域4站位同步观测的沉积动力数据,采用Scully和Sommerfield改进的通量机制分解法来获取垂向各层平... 河口悬沙输运对于最大浑浊带形成发育、地貌演变、港口航道安全、水质以及生态系统健康至关重要。本文基于2017年洪季长江口南槽拦门沙海域4站位同步观测的沉积动力数据,采用Scully和Sommerfield改进的通量机制分解法来获取垂向各层平流通量和潮泵通量及累积动态变化,以确定平流和潮汐泵送对悬沙净通量的相对贡献,探讨纵向和横向的水沙输运时空格局和动力机制,弥补了传统通量机制分解法仅限计算时空平均值的缺陷。研究发现:(1)洪季长江口南槽拦门沙海域大潮期间存在横向余环流,小潮期间出现表层向海、底层向陆的纵向余环流;(2)平流和潮泵作用是影响净输运的关键因素,南槽拦门沙海域由平流作用主导、悬沙向海净输运,横向上向西南边滩输运,为南汇边滩围垦区向海淤长提供物源,且靠近主槽区域横向悬沙通量对沉积过程的贡献与纵向通量相当;(3)潮泵输运在河口滞流点和拦门沙海域均较显著,泵送的大小和方向与径潮流相互作用和底床物源有关,纵向上由大潮期间向陆泵送占优转为小潮期间的向海净输运占优。综上,南槽拦门沙海域近底层悬沙呈现由浅滩向主槽辐聚的格局,浅滩区域的近底层悬沙净输运受潮泵作用控制,且对整个水柱悬沙输运贡献显著,可能是拦门沙形成和最大浑浊带发育的重要机制。 展开更多
关键词 长江口南槽 通量机制分解 平流作用 潮泵作用 悬沙输运
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气动隔膜泵水力性能试验研究
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作者 张永江 常智新 +2 位作者 高彦峰 黄福友 陈传宝 《阀门》 2024年第1期51-55,共5页
为确定气动隔膜泵输送常温推进剂的工作性能,对气动隔膜泵的水力性能进行试验研究。气动隔膜泵首次应用于常温推进剂加注系统,用于加注后的管路内残存推进剂的输送,有必要对其工作性能进行详细研究。本文通过试验方法,对不同供气压力条... 为确定气动隔膜泵输送常温推进剂的工作性能,对气动隔膜泵的水力性能进行试验研究。气动隔膜泵首次应用于常温推进剂加注系统,用于加注后的管路内残存推进剂的输送,有必要对其工作性能进行详细研究。本文通过试验方法,对不同供气压力条件下气动隔膜泵输送流量、气体流量以及双泵并联输送液体流量进行了测量,并对影响气动隔膜泵水力性能的因素进行了详细分析。试验结果表明,随着供气压力的提高,气动隔膜泵输送液体的流量增加,输送气体的流量反而减小;两个减压阀供气时,双泵并联输送液体的流量是约单泵工作时的2倍。试验结果为隔膜泵抽吸常温液体推进剂的应用提供参考。 展开更多
关键词 气动隔膜泵 常温推进剂 输送 水力性能
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多相混输泵用超高压机械密封性能研究
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作者 任宝杰 郝木明 +2 位作者 沈宗沼 赵伟龙 郭崇斌 《炼油技术与工程》 CAS 2024年第5期33-36,48,共5页
针对超高压混输泵机械密封易磨损失效的问题,介绍了端面槽加工和涂层应用两种策略,用热流固耦合分析方法,分析了浅槽微接触式机械密封在实际应用中的温度分布和端面变形情况,阐述了表面涂层技术的应用,进行了一系列机械密封性能的试验... 针对超高压混输泵机械密封易磨损失效的问题,介绍了端面槽加工和涂层应用两种策略,用热流固耦合分析方法,分析了浅槽微接触式机械密封在实际应用中的温度分布和端面变形情况,阐述了表面涂层技术的应用,进行了一系列机械密封性能的试验研究。研究结果不仅证实了这些技术在提高机械密封寿命和可靠性方面的有效性,还证实了端面开槽和涂层技术在降低摩擦、改善耐磨性能方面的显著效果。为超高压混输泵机械密封系统的设计和优化提供了重要的理论依据及实践指导。 展开更多
关键词 多相混输泵 超高压 机械密封 浅槽微接触 温度场 变形计算 表面涂层 摩擦扭矩
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基于多重对应分析与Logistic回归探究IABP支持下心血管危重患者院内转运不良事件的危险因素
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作者 孙卓铖 王宇 +3 位作者 魏松奇 樊方慧 马凌燕 杨巧芳 《临床医学研究与实践》 2024年第13期12-17,共6页
目的分析主动脉内球囊反搏(IABP)支持下心血管危重患者院内转运不良事件现状及危险因素。方法选取2022年11月至2023年6月郑州市某两所三甲医院进行院内转运的IABP支持的心血管危重患者为研究对象,根据是否发生院内转运不良事件进行分组... 目的分析主动脉内球囊反搏(IABP)支持下心血管危重患者院内转运不良事件现状及危险因素。方法选取2022年11月至2023年6月郑州市某两所三甲医院进行院内转运的IABP支持的心血管危重患者为研究对象,根据是否发生院内转运不良事件进行分组,通过单因素分析、二元Logistic回归分析筛选危险因素;采用多重对应分析探索不同类型不良事件与危险因素的关联程度。结果182例患者转运中有68例(37.36%)发生了不良事件,病情变化类不良事件发生率最高(43/23.63%),不良事件主要为血压波动(26/14.29%)、IABP氦气管路断开(16/8.79%)和血氧饱和度(SpO2)变化(10/5.49%)。使用儿茶酚胺类药物、转运目的地是IABP支持下心血管危重患者院内转运不良事件发生的危险因素(P<0.05)。多重对应分析显示病情变化不良事件与机械通气、镇痛镇静药物相关联。结论IABP支持下心血管危重患者院内转运不良事件发生率较高,临床医护人员应重视相关危险因素的识别,并采取综合措施提高患者院内转运的安全性。 展开更多
关键词 主动脉内球囊反搏 心血管危重患者 院内转运 不良事件 多重对应分析
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Investigation of impurity transport using laser blow-off technique in the HL-2A Ohmic and ECRH plasmas 被引量:3
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作者 张凯 崔正英 +8 位作者 孙平 董春凤 邓玮 董云波 宋绍栋 蒋敏 李永高 卢平 杨青巍 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期296-304,共9页
Impurity transports in two neighboring discharges with and without electron cyclotron resonance heating(ECRH)are studied in the HL-2A tokamak by laser blow-off(LBO) technique.The progression of aluminium ions as t... Impurity transports in two neighboring discharges with and without electron cyclotron resonance heating(ECRH)are studied in the HL-2A tokamak by laser blow-off(LBO) technique.The progression of aluminium ions as the trace impurity is monitored by soft x-ray(SXR) and bolometer detector arrays with good temporal and spatial resolutions.Obvious difference in the time trace of the signal between the Ohmic and ECRH L-mode discharges is observed.Based on the numerical simulation with one-dimensional(1D) impurity transport code STRAHL,the radial profiles of impurity diffusion coefficient D and convective velocity V are obtained for each shot.The result shows that the diffusion coefficient D significantly increases throughout the plasma minor radius for the ECRH case with respect to the Ohmic case,and that the convection velocity V changes from negative(inward) for the Ohmic case to partially positive(outward) for the ECRH case.The result on HL-2A confirms the pump out effect of ECRH on impurity profile as reported on various other devices. 展开更多
关键词 impurity transport LBO numerical simulation pump out
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Valley-polarized pumping current in zigzag graphene nanoribbons with different spatial symmetries
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作者 俞之舟 许富明 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期110-114,共5页
We numerically investigate the valley-polarized current in symmetric and asymmetric zigzag graphene nanoribbons(ZGNRs) by the adiabatic pump, and the effect of spatial symmetry is considered by introducing different p... We numerically investigate the valley-polarized current in symmetric and asymmetric zigzag graphene nanoribbons(ZGNRs) by the adiabatic pump, and the effect of spatial symmetry is considered by introducing different pumping regions. It is found that pumping potentials with the symmetry Vp(x,y) = Vp(-x,y)can generate the largest valleypolarized current. The valley-polarized currents I13~L with the pumping potential symmetry Vp(x,y) =Vp(x,-y,) and I14~L with Vp(x,y) = Vp(-x,-y) of symmetric ZGNRs are much smaller than those of asymmetric ZGNRs. We also find I13~L and I14~L of symmetric ZGNRs decrease and increase with the increasing pumping amplitude, respectively. Moreover, the dephasing effect from the electron-phonon coupling within the Buttiker dephasing scheme is introduced. The valley-polarized current of the symmetric ZGNRs with Vp(x,y)= Vp(x,-y) increases with the increase of the dephasing strength while that with Vp(x,y) = Vp(-x,-y) decreases as the dephasing strength increases. 展开更多
关键词 valley polarization charge pump graphene quantum transport
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Mechanisms Efflux Pumps of <i>Acinetobacter baumannii</i>(MDR): Increasing Resistance to Antibiotics
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作者 Francis T. Dongmo Temgoua Liang Wu 《Journal of Biosciences and Medicines》 2019年第1期48-70,共23页
Acinetobacter baumannii has greatly increased its degree of resistance to become multidrug resistant (MDR) over the past 30 years and is on the red line of the most widely replicated bacteria according to World Health... Acinetobacter baumannii has greatly increased its degree of resistance to become multidrug resistant (MDR) over the past 30 years and is on the red line of the most widely replicated bacteria according to World Health Organization (WHO). The efflux pumps are the main cause for the increasing antibiotic resistance of A. baumannii originated from nosocomial infection. The progressive resistance of A. baumannii even on the recent drugs (tigecycline and fosfomycin) reduces to very effective antibiotic scale. With attention focused on MDR and pan-drug-resistant (PDR) in A. baumannii multiple works on efflux pumps chemical inhibitor (NMP, PAβN, omeprazole, verapamil, reserpine, CCCP) are still in progress. Certain inhibitors from plants (Biricodar and timcodar, Falvone, Mahonia, Dalea versicolor, Lycopus europaeus, and Rosmarinus officinalis) have the capability to have such compounds according to their very significant synergistic effect with antibiotics. In this review we focused on the growth of antibiotic resistance to explain the mechanism of efflux pumps into these different super families and a comprehensive understanding of the extrusion, regulation and physiology role of drug efflux pumps in the essential development of anti-resistivity drugs. We recapitulated the evolution of the work carried out in these fields during the last years and in the course of elaboration, with the aim of increasing the chances of decreasing bacterial resistivity to antibiotics. 展开更多
关键词 Acinetobacter BAUMANNII RND EFFLUX pumpS EFFLUX transporters Multidrug Resistant (MDR) EFFLUX pumpS Inhibitors (EPIs)
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Partial external biliary diversion in bile salt export pump deficiency: Association between outcome and mutation 被引量:4
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作者 Philipp Ellinger Jan Stindt +13 位作者 Carola Droge Katharina Sattler Claudia Stross Stefanie Kluge Diran Herebian Sander HJ Smits Martin Burdelski Sebastian Schulz-Jürgensen Antje Ballauff Jan Schulte am Esch Ertan Mayatepek Dieter Haussinger Ralf Kubitz Lutz Schmitt 《World Journal of Gastroenterology》 SCIE CAS 2017年第29期5295-5303,共9页
AIM To investigate the relation of two different mutations to the outcome of partial external biliary diversion(PEBD)in severe bile salt export pump(BSEP) deficiency.METHODS Mutations in the gene encoding BSEP leading... AIM To investigate the relation of two different mutations to the outcome of partial external biliary diversion(PEBD)in severe bile salt export pump(BSEP) deficiency.METHODS Mutations in the gene encoding BSEP leading to severe BSEP deficiency in two unrelated patients were identified by genomic sequencing. Native liver biopsies and transiently transfected human embryonic kidney(HEK) 293 cells expressing either wild-type or mutated BSEP were subjected to immunofluorescence analysis to assess BSEP transporter localization. Bile acid profiles of patient and control bile samples were generated by ultra-performance liquid chromatographytandem mass spectrometry. Wild-type and mutant BSEP transport of [~3H]-labeled taurocholate(TC) and taurochenodeoxycholate(TCDC) was assessed by vesicular transport assays.RESULTS A girl(at 2 mo) presented with pruritus, jaundice and elevated serum bile salts(BS). PEBD stabilized liver function and prevented liver transplantation. She was heterozygous for the BSEP deletion p.T919 del and the nonsense mutation p.R1235 X. At the age of 17 years relative amounts of conjugated BS in her bile were normal, while total BS were less than 3% as compared to controls. An unrelated boy(age 1.5 years) presenting with severe pruritus and elevated serum BS was heterozygous for the same nonsense and another missense mutation, p.G1032 R. PEBD failed to alleviate pruritus, eventually necessitating liver transplantation. BS concentration in bile was about 5% of controls. BS were mainly unconjugated with an unusual low amount of chenodeoxycholate derivatives(< 5%). The patients' native liver biopsies showed canalicular BSEP expression. Both BSEP p.T919 del and p.G1032 R were localized in the plasma membrane in HEK293 cells. In vitro transport assays showed drastic reduction of transport by both mutations. Using purified recombinant BSEP as quantifiable reference, per-molecule transport rates for TC and TCDC were determined to be 3 and 2 BS molecules per wild-type BSEP transporter per minute, respectively.CONCLUSION In summary, our findings suggest that residual function of BSEP as well as substrate specificity influence the therapeutic effectiveness of PEBD in progressive familial intrahepatic cholestasis type 2(PFIC-2). 展开更多
关键词 家庭 intrahepatic cholestasis 类型 2 部分外部胆汁的转向 胆汁盐出口泵 ATP 有约束力的盒子 transporter Intrahepatic cholestasis
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Emanuel Strehler’s work on calcium pumps and calcium signaling
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作者 Emanuel E Strehler 《World Journal of Biological Chemistry》 CAS 2011年第4期67-72,共6页
Cells are equipped with mechanisms to control tightly the influx, efflux and resting level of free calcium (Ca 2+ ). Inappropriate Ca 2+ signaling and abnormal Ca 2+ levels are involved in many clinical disorders incl... Cells are equipped with mechanisms to control tightly the influx, efflux and resting level of free calcium (Ca 2+ ). Inappropriate Ca 2+ signaling and abnormal Ca 2+ levels are involved in many clinical disorders including heart disease, Alzheimer's disease and stroke. Ca 2+ also plays a major role in cell growth, differentiation and motility; disturbances in these processes underlie cell transformation and the progression of cancer. Accordingly, research in the Strehler laboratory is focused on a better understanding of the molecular "toolkit" needed to ensure proper Ca 2+ homeostasis in the cell, as well as on the mechanisms of localized Ca 2+ signaling. A longterm focus has been on the plasma membrane calcium pumps (PMCAs), which are linked to multiple disorders including hearing loss, neurodegeneration, and heart disease. Our work over the past 20 years or more has revealed a surprising complexity of PMCA isoforms with different functional characteristics, regulation, and cellular localization. Emerging evidence shows how specific PMCAs contribute not only to setting basal intracellular Ca 2+ levels, but also to local Ca 2+ signaling and vectorial Ca 2+ transport. A second major research arearevolves around the calcium sensor protein calmodulin and an enigmatic calmodulin-like protein (CALML3) that is linked to epithelial differentiation. One of the cellular targets of CALML3 is the unconventional motor protein myosin-10, which raises new questions about the role of CALML3 and myosin-10 in cell adhesion and migration in normal cell differentiation and cancer. 展开更多
关键词 CALCIUM signaling CALCIUM transport CALMODULIN Membrane TRAFFICKING Myosin-10 CALCIUM ATPASE CALCIUM pumpS STRUCTURE-FUNCTION relationship
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Temperature dependence of spin pumping in YIG/NiO(x)/W multilayer
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作者 倪丽君 王文强 +13 位作者 金立川 叶建东 巩贺贺 战翔 陈振东 张龙龙 代兴泽 黎遥 张荣 杨燚 张怀武 刘荣华 陈丽娜 徐永兵 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期678-682,共5页
We report the temperature dependence of the spin pumping effect for Y_(3)Fe_(5)O_(12)(YIG,0.9μm)/NiO(tNiO)/W(6 nm)(tNiO=0 nm,1 nm,2 nm,and 10 nm)heterostructures.All samples exhibit a strong temperature-dependent inv... We report the temperature dependence of the spin pumping effect for Y_(3)Fe_(5)O_(12)(YIG,0.9μm)/NiO(tNiO)/W(6 nm)(tNiO=0 nm,1 nm,2 nm,and 10 nm)heterostructures.All samples exhibit a strong temperature-dependent inverse spin Hall effect(ISHE)signal I_(c)and sensitivity to the NiO layer thickness.We observe a dramatic decrease of I_(c)with inserting thin NiO layer between YIG and W layers indicating that the inserting of NiO layer significantly suppresses the spin transport from YIG to W.In contrast to the noticeable enhancement in YIG/NiO(tNiO≈1-2 nm)/Pt,the suppression of spin transport may be closely related to the specific interface-dependent spin scattering,spin memory loss,and spin conductance at the NiO/W interface.Besides,the I_(c)of YIG/Ni O/W exhibits a maximum near the TNof the AF NiO layer because the spins are transported dominantly by incoherent thermal magnons. 展开更多
关键词 spin pumping effect spin transport charge current I_(c) linewidth△H temperature dependence
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复杂工况下深海采矿混输泵有限元分析 被引量:1
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作者 王凯 陆钇霖 +4 位作者 刘厚林 程智明 管禹 邹丽 王磊 《排灌机械工程学报》 CSCD 北大核心 2023年第4期331-337,共7页
采用流固耦合及有限元方法对布放和混输等复杂工况下3级深海采矿混输泵进行强度计算,分析了泵内流场分布、转子部件应力应变及临界转速,并进行了500 m级深海采矿混输系统海上试验.结果表明:设计流量下,混输泵的计算扬程为124.30 m,相对... 采用流固耦合及有限元方法对布放和混输等复杂工况下3级深海采矿混输泵进行强度计算,分析了泵内流场分布、转子部件应力应变及临界转速,并进行了500 m级深海采矿混输系统海上试验.结果表明:设计流量下,混输泵的计算扬程为124.30 m,相对误差为0.27%;布放工况时,混输泵最大变形仅为0.36500 mm,最大应力为73.971 MPa;混输工况时,泵最大变形为0.31500 mm,最大应力为58.860 MPa;转子部件前3阶模态仅沿泵轴方向变形,并未发生扭曲,而后3阶模态呈“S”形扭曲变形;转子部件1阶固有频率对应临界转速为2476 r/min;海试布放过程中混输泵安全可靠,混输工况下泵稳定运行时长超过57 h,实现了2次24 h连续无故障运行,且矿石颗粒体积浓度达到11.7%. 展开更多
关键词 混输泵 深海采矿 布放 有限元分析 海上试验
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大流量无堵塞旋流泵的优化设计及实验研究
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作者 李洪彬 蒋爽 +2 位作者 倪福生 钟卫华 王勇 《水道港口》 2023年第1期150-156,共7页
依据三要素设计方法及相关经验公式,对大流量无堵塞旋流泵主要结构参数的尺寸进行初步确定,用ANSYS CFX软件对初始设计的旋流泵进行外特性预测后发现,工况点处扬程仅达到设计扬程的77.1%,效率高出设计效率的24.2%。对主要部件叶轮外径D ... 依据三要素设计方法及相关经验公式,对大流量无堵塞旋流泵主要结构参数的尺寸进行初步确定,用ANSYS CFX软件对初始设计的旋流泵进行外特性预测后发现,工况点处扬程仅达到设计扬程的77.1%,效率高出设计效率的24.2%。对主要部件叶轮外径D 2、宽度b 2和包角ψ等进行逐步优化,得到较优化的旋流泵模型,该泵工况点处扬程高出设计扬程3.2%,效率高出设计效率30.5%。为了验证模拟计算的准确性,对实体旋流泵进行了清水输送实验,工况点处实验扬程高出模拟扬程0.7%,实验效率高出模拟效率6.4%。 展开更多
关键词 无堵塞旋流泵 叶轮 输送实验
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深海矿产混输装备防堵塞调控技术与应用研究
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作者 沈丹 郑鹏 +2 位作者 王磊 张家锐 占剑锋 《船舶与海洋工程》 2023年第2期45-49,共5页
为解决深海矿产混输系统中泵管堵塞影响矿物过泵能力的问题,针对3 000米级固液两相流混输装备系统提出深海混输泵防堵塞调控技术方案。通过对混输系统堵塞状态的判断、自动控制策略的研究和混输装备软硬件系统的设计,实现对混输系统的... 为解决深海矿产混输系统中泵管堵塞影响矿物过泵能力的问题,针对3 000米级固液两相流混输装备系统提出深海混输泵防堵塞调控技术方案。通过对混输系统堵塞状态的判断、自动控制策略的研究和混输装备软硬件系统的设计,实现对混输系统的防堵塞调控;通过混输装备系统500米级海试,验证该方案的合理性、可靠性和稳定性,为后续深海混输装备的智能控制研究提供参考。 展开更多
关键词 深海矿产混输 固液混输 深海混输泵 防堵塞调控 专家PID技术
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旋涡泵进口含气量和叶片数对泵内流场和性能的影响分析
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作者 张人会 段鹏 杨伟峰 《兰州理工大学学报》 CAS 北大核心 2023年第3期36-42,共7页
为分析旋涡泵气液混输时进口含气量和叶片数对泵内流场和外特性的影响机理,通过数值计算,对不同进口含气量(5%、10%、15%)和不同叶片数(20、22、24、28)时旋涡泵内流场和外特性进行对比分析.结果表明:旋涡泵的扬程和效率随着进口含气量... 为分析旋涡泵气液混输时进口含气量和叶片数对泵内流场和外特性的影响机理,通过数值计算,对不同进口含气量(5%、10%、15%)和不同叶片数(20、22、24、28)时旋涡泵内流场和外特性进行对比分析.结果表明:旋涡泵的扬程和效率随着进口含气量的增大而减小,扬程从48.98 m减小到36.19 m,效率从34.8%减小到32.4%;在各纵向截面上侧流道内压力大于叶轮流道内压力,从叶轮进口到出口沿圆周方向,各纵向截面内叶轮与壳体的最大压差逐渐增大;纵向截面上气液分离现象越来越严重,叶轮内气体体积分数逐渐增大,而侧流道内气体体积分数逐渐减小,叶轮轮毂处气相聚集越来越严重;随着叶片数的增加,旋涡泵的扬程和效率均呈先增后减的趋势;随着进口含气量的增大,旋涡泵的性能随叶片数变化的敏感度先增后减. 展开更多
关键词 旋涡泵 气液混输 气液两相流 叶片数
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基于神经网络PID的疏浚管道泥浆流速控制
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作者 蒋爽 刘世纪 +1 位作者 高礼科 倪福生 《计算机测量与控制》 2023年第11期198-203,220,共7页
疏浚作业中,泥浆管道内物料的组成、粒径、浓度等随水下地形土质等变化很大,易造成流速波动甚至堵管、爆管等故障,因此泥浆流速稳定控制对泥浆输送的效率和安全具有重要意义;疏浚管道输送系统具有非线性、大时滞和参数时变等特征,传统PI... 疏浚作业中,泥浆管道内物料的组成、粒径、浓度等随水下地形土质等变化很大,易造成流速波动甚至堵管、爆管等故障,因此泥浆流速稳定控制对泥浆输送的效率和安全具有重要意义;疏浚管道输送系统具有非线性、大时滞和参数时变等特征,传统PID控制方法效果不佳,故此将BP神经网络和传统PID控制算法相结合,并将其应用于泥浆流速控制中;以河海大学管道输送实验平台为对象,采用受控自回归CAR模型描述泥泵变频器频率与管道泥浆流速之间的关系,通过实验和数值处理对模型进行离线辨识;在此基础上通过仿真对比传统PID、单神经元PID和BP-PID的流速控制性能,发现BP-PID控制器的超调量仅为3.8%,响应时间为11 s,控制性能较好;最后通过在体积浓度-10%到-30%泥浆范围内,泥浆浓度小幅度和大幅度增减实验,对流速控制方法进行了验证,结果表明在浓度平缓或剧烈波动时,采用BP-PID控制算法的流速控制系统,均能够在保证输送安全的前提下,快速、稳定地达到目标流速,具有较好的自适应控制性能。 展开更多
关键词 疏浚工程 泥浆流速控制 泥泵管道输送实验台 受控自回归模型 神经网络PID 单神经元PID
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