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Pipelines vibration analysis and control based on clamps'locations optimization of multi-pump system

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Chinese Journal of Aeronautics 2022年第6期35卷 352-366页

作者： Xin LI Weihao LI Jian SHI Qiang LI Shaoping WANG School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China School of Automation Science and Electric Engineering Beihang UniversityBeijing 100191China

The violent vibration of hydraulic pipelines in aircraft may cause faults or even an accident,especially for the large aircraft with the multi-pump system because of different vibration sources and complex pipelines system.Aiming to the vibration analysis and control of the multipump system,this paper proposed the clamps’locations optimization to minimize the system impedance at vibration frequencies.Firstly,the models of the flexible clamp and other components in multi-pump system were established,based on which,the system impedance was calculated by using Transfer Matrix Method(TMM);Secondly,the objective function is defined as weighted sum of system impedance at frequencies of different vibration sources.Then,the clamps’locations were altered to change the system impedance.Moreover,The Chaotic Swarm Particle Optimization(CPSO)algorithm was applied to obtain the optimal clamps’locations and the minimum value of objective function which decreased by 36.4%compared to the value of original clamps’locations;Finally,the experiments from vibration and pressure test with original and optimized clamps’locations verified the effectiveness of the system impedance calculation and clamps’locations optimization method.

关键词： clamp CPSO Impedance Multi-pump Pipeline TMM Vibration

Prenatal exposure to perfluorooctane sulfonate and perfluorooctanoate and the risk of preeclampsia: a nested case-control study in Shanghai, China

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Chinese Medical Journal 2023年第7期136卷 857-859页

作者： Ying Zhao Jizi Zhou Huangfang Xu Huanqiang Zhao Ping An Xiaotian Li Yu Xiong Obstetrics and Gynecology Hospital Fudan UniversityShanghai 200090China Shenzhen Maternity&Child Healthcare Hospital ShenzhenGuangdong 518028China

To the Editor:Preeclampsia presents with new-onset hypertension and maternal multi-organ injury that is associated with substantial maternal and fetal morbidity and mortality.[1]Although the etiology remains a mystery,environmental toxicants,especially those that interact with genetic factors and disrupt normal placental function,are emerging as potential risk factors for preeclampsia.

关键词： mortality fetal clamp

WHOLE-CELL clamp STUDY OF XENOPUS EMBRYONIC CHOLINERGIC NEURONS

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Science China Chemistry 1989年第2期32卷 148-154页

作者：谢佐平王堤竺煜杰 Department of Biology Tsinghua University Beijing

Whole-cell clamped myoballs are placed into direct visible contact with the growth cones of isolated neurons in embryonic Xenopus culture to serve as probe of acetylchollne (AcCHo) release in order to determine whether these neurons are cholinergic or not. Using a GQ-seal, whole-cell recording method, the electrophysiological properties of these identified cholinergic neurons are studied. It is found that these embryonic neurons, like adult frog motor neurons, exhibit repetitive firings in a certain embryonic developing stage. A development of repetitive firings is observed simultaneously. Tracing the development of one neuron, we find that the development of repetitive firing is completed at the 48th h after fertilization. Tetrodotoxin (TTX) which blocks Na^+ channels can abolish all firings; and tetraethyl ammonium chloride (TEA), the blocker of K^+ channels, reverses this development, i. e. it makes the repetitive firings disappear again. These data show that the nature of the development of

关键词： whole-cell clamp cholinergic neurous repetitive firings Xenopus embryo.

Design Study of Top Lid with clamp Structure in JT-60SA Cryostat

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Plasma Science and Technology 2013年第2期15卷 188-191页

作者： Shigetoshi NAKAMURA Yusuke K. SHIBAMA Kei MASAKI Akira SAKASAI Japan Atomic Energy Agency Mukouyama 801-1 Naka Ibaraki 311-0193 Japan

JT-60SA is a fully superconducting coil tokamak upgraded from the JT-60U. This paper focused on the integrity of the top lid of cryostat in JT-60SA. The design requirement for the cryostat in normal operations is to achieve vacuum insulation of 10-1 Pa, and the top flange of the top lid is lightly welded onto its body flange. The weld is tensile-loaded by bending deformation of the top lid due to vacuum pressure of external 0.1 MPa. This weld integrity is evaluated with tensile-load reduction, which results in clamp reinforcement. The structural integrity of the top lid is validated.

关键词： clamp vacuum insulation top lid cryostat JT-60SA

Expression and effect of sodium-potassium-chloride cotransporter on dorsal root ganglion neurons in a rat model of chronic constriction injury

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Neural Regeneration Research 2020年第5期15卷 912-921页

作者： Chao-Yang Tan Yan-Ping Wang Yuan-Yuan Han Bi-Han Lu Wei Ji Li-Cang Zhu Yang Wang Wen-Yan Shi Li-Ya Shan Liang Zhang Ke-Tao Ma Li Li Jun-Qiang Si Department of Physiology College of MedicineShihezi UniversityShiheziXinjiang Uygur Autonomous RegionChina Department of Physiology Medical College of Jiaxing UniversityJiaxingZhejiang ProvinceChina Department of Health Karamay Army DivisionChinese People’s Liberation ArmyKaramayXinjiang Uygur Autonomous RegionChina Department of Nursing Medical College of Jiaxing UniversityJiaxingZhejiang ProvinceChina Department of Clinical Medicine Karamay College of Xinjiang Medical UniversityKaramayXinjiang Uygur Autonomous RegionChina Department of Neurosurgery First Affiliated HospitalCollege of MedicineShihezi UniversityShiheziXinjiang Uygur Autonomous RegionChina The key Laboratory of Xinjiang Endemic and Ethnic Diseases College of MedicineShihezi UniversityShiheziXinjiang Uygur Autonomous RegionChina Department of Physiology School of Basic Medical SciencesWuhan UniversityWuhanHubei ProvinceChina Department of Physiology School of Basic Medical SciencesHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Sodium-potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) are associated with the transmission of peripheral pain.We investigated whether the increase of NKCC1 and KCC2 is associated with peripheral pain transmission in dorsal root ganglion neurons.To this aim,rats with persistent hyperalgesia were randomly divided into four groups.Rats in the control group received no treatment,and the rat sciatic nerve was only exposed in the sham group.Rats in the chronic constriction injury group were established into chronic constriction injury models by ligating sciatic nerve and rats were given bumetanide,an inhibitor of NKCC1,based on chronic constriction injury modeling in the chronic constriction injury + bumetanide group.In the experiment measuring thermal withdrawal latency,bumetanide (15 mg/kg) was intravenously administered.In the patch clamp experiment,bumetanide (10 μg/μL) and acutely isolated dorsal root ganglion neurons (on day 14) were incubated for 1 hour,or bumetanide (5 μg/μL) was intrathecally injected.The Hargreaves test was conducted to detect changes in thermal hyperalgesia in rats.We found that the thermal withdrawal latency of rats was significantly decreased on days 7,14,and 21 after model establishment.After intravenous injection of bumetanide,the reduction in thermal retraction latency caused by model establishment was significantly inhibited.Immunohistochemistry and western blot assay results revealed that the immune response and protein expression of NKCC1 in dorsal root ganglion neurons of the chronic constriction injury group increased significantly on days 7,14,and 21 after model establishment.No immune response or protein expression of KCC2 was observed in dorsal root ganglion neurons before and after model establishment.The Cl^– (chloride ion) fluorescent probe technique was used to evaluate the change of Cl^– concentration in dorsal root ganglion neurons of chronic constriction injury model rats.We found that the relative optical density of N-(ethoxycarb

关键词： bumetanide chronic constriction injury dorsal root ganglion dorsal root reflex hyperalgesia KCC2 nerve regeneration neuropathic pain NKCC1 primary afferent depolarization whole-cell patch clamp

A dynamic modeling approach for nonlinear vibration analysis of the L-type pipeline system with clamps

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Chinese Journal of Aeronautics 2020年第12期33卷 3253-3265页

作者： Qingdong CHAI Jin ZENG Hui MA Kun LI Qingkai HAN School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern UniversityShenyang 110819China

There exists a lot of research on the nonlinear vibration of the pipeline system with different boundary conditions.To the best of our knowledge,little research on the actual constraint of the clamp has been performed.In this paper,according to hysteresis loops of the clamp obtained from experimental test,the simplified bilinear stiffness and damping model is proposed.Then the Finite Element(FE)model of L-type pipeline system with clamps is established using Timoshenko beam theory in combination with aforementioned stiffness-damping model.Both hammering and shaker tests verify the FE model via the comparisons of natural frequencies and vibration responses.The results show that the maximum errors of natural frequencies and vibration responses are about 8.31%and 17.6%,respectively.The proposed model can simulate the dynamic characteristics of the L-type pipeline system with clamps well,which is helpful to provide some guidance for the early design stage of pipeline in aero-engine.

关键词： clamp Dynamic modeling Experimental test Finite element Nonlinear vibration Pipeline

The effects of rises in external K^+ on the hyperpolarization-activated cation current I_h in rat dorsal root ganglion neurons

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Science China Chemistry 2009年第8期52卷 1258-1263页

作者： DU ZhengQing WU WenJie ZHOU YuFen Department of Environmental Science Shanxi University of Finance and EconomicsTaiyuan 030006China

The effects of rises in external K+(Kext) were examined on the hyperpolarization-activated cation current(Ih) in rat dorsal root ganglion neurons using the whole-cell patch clamp technique.The results showed that Kext increased Ih in a certain concentration and voltage-dependent manner.At the basal Kext level(4 mmol/L),Ih had a maximal amplitude of 1085 ± 340 pA which was enhanced by ～45% and ～92% at 8 and 16 mmol/L Kext,respectively.The midpoint activation voltage was significantly shifted from -98 mV in the hyperpolarizing direction by 8 and 12 mV at 8 and 16 mmol/L Kext,respectively with alteration of the activation course of Ih.The short time constants of activation became longer with the increasing amplitude of the command potential upon rises in Kext.The long time constants became shorter.The reversal potentials were shifted in the positive direction without significant alterations upon rises in Kext.According to the functional role of Ih,Kext increased Ih,resulting in an enhanced neuronal excitability,which might produce activation potential abnormality and perhaps neuropathic pain involved.

关键词： hyperpolarization-activated inward current external potassium dorsal root ganglion neurons patch clamp

GM-CSF-induced Ca_(2+) -activated non-voltage-dependent inwardly rectifying K_+ channel in murine peritoneal exudate macrophages

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Chinese Science Bulletin 1997年第11期42卷 947-952页

作者： ZHANG Xiaofeng, FENG Meifu, WU Caihong and ZHOU Pei’aiState Key Laboratory of Biomembrane and Membrane Biotechnology, Chinese Academy of Sciences, Beijing 100080, China 1 . In-stitute of Zoology, Chinese Academy of Sciences, Beijing 100080, China 2 College of Life Sciences, Peking University, Beijing 100871, China State Key Laboratory of Biomembrane and Membrane Biotechnology Chinese Academy of Sciences Beijing China Institute of Zoology Chinese Academy of Sciences Beijing China College of Life Sciences Peking University Beijing China

GRANULOCYTE-MACROPHAGE colony-stimulating factor(GM-CSF),a member in the family ofglycoprotein cytokines,can not only act to stimulate proliferation of immature progenitors,butalso enhance differentiated functions of mature effector cell.It has two kinds of biologicaleffects on mature effector cells,i.***.direct effect and indirect effect.The latter is also

关键词： K+ channel patch clamp GM-CSF macrophage.

Na^+-permeable channels of human sperm membrane reassembled into giant liposome

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Chinese Science Bulletin 2001年第13期46卷 1085-1088页

作者： Zhang Guangping Bai Junping Shi Yuliang Chinese Acad Sci Shanghai Inst Biol Sci Shanghai Inst Physiol Shanghai 200031 Peoples R China

Previous data showed that a Na+-transmem-brane flux was accompanied with acrosome reaction of sperm. However, the electrophysiological recording and characterization of Na+ current in human sperm membrane have not been yet reported. In the present investigation, membrane proteins extracted from human sperms were reassembled into liposome bilayer, and then the liposomes were fused by dehydration-rehydration into giant liposomes with the diameter of more than 10μm. By patch clamping the giant liposomes two kinds of single channel currents were recorded in a NaCl solution system. Both of them were Na+-carried, TTX-sensitive and strongly rectifying, but with different unit conductance and open probability. Moreover, bursting activity and channel-substates as well as two open time constants were observed in the larger channel.

关键词： patch clamp giant liposome single channel human sperm Na+-channel.