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Osmotic pressure of serum and cerebrospinal fluid in patients with suspected neurological conditions 预览
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作者 Tetsuya Akaishi Toshiyuki Takahashi +3 位作者 Ichiro Nakashima Michiaki Abe Masashi Aoki Tadashi Ishii 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第5期944-947,共4页
Interstitial fluid movement in the brain parenchyma has been suggested to contribute to sustaining the metabolism in brain parenchyma and maintaining the function of neurons and glial cells.The pulsatile hydrostatic p... Interstitial fluid movement in the brain parenchyma has been suggested to contribute to sustaining the metabolism in brain parenchyma and maintaining the function of neurons and glial cells.The pulsatile hydrostatic pressure gradient may be one of the driving forces of this bulk flow.However,osmotic pressure- related factors have not been studied until now.In this prospective observational study,to elucidate the relationship between osmolality (mOsm/kg) in the serum and that in the cerebrospinal fluid (CSF),we simultaneously measured the serum and CSF osmolality of 179 subjects with suspected neurological conditions.Serum osmolality was 283.6 ± 6.5 mOsm/kg and CSF osmolality was 289.5 ± 6.6 mOsm/kg.Because the specific gravity of serum and CSF is known to be 1.024–1.028 and 1.004–1.007,respectively,the estimated average of osmolarity (mOsm/L) in the serum and CSF covered exactly the same range (i.e.,290.5–291.5 mOsm/L).There was strong correlation between CSF osmolality and serum osmolality,but the difference in osmolality between serum and CSF was not correlated with serum osmolality,serum electrolyte levels,protein levels,or quotient of albumin.In conclusion,CSF osmolarity was suggested to be equal to serum osmolarity.Osmolarity is not one of the driving forces of this bulk flow.Other factors such as hydrostatic pressure gradient should be used to explain the mechanism of bulk flow in the brain parenchyma.This study was approved by the Institutional Review Board of the Tohoku University Hospital (approval No.IRB No.2015-1-257) on July 29,2015. 展开更多
关键词 brain PARENCHYMA bulk flow CEREBROSPINAL FLUID hydrostatic PRESSURE interstitial FLUID OSMOLARITY OSMOTIC PRESSURE
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Spatiotemporal expression of leukemia inhibitory factor receptor protein during neural tube development in embryos with neural tube defects 预览
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作者 Dong An Xiao-Wei Wei +3 位作者 He-Nan Zhang Dan Liu Wei Ma Zheng-Wei Yuan 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期705-711,共7页
Leukemia inhibitory factor receptor(LIFR),as a neuroregulatory cytokine receptor,generally shows a neuroprotective effect in central nervous system injuries.In this study,to understand the effect of LIFR on pathogenes... Leukemia inhibitory factor receptor(LIFR),as a neuroregulatory cytokine receptor,generally shows a neuroprotective effect in central nervous system injuries.In this study,to understand the effect of LIFR on pathogenesis of neural tube defects,we explored spatiotemporal expression of LIFR at different stages of fetal development in normal and neural tube defect embryos.Spina bifida aperta was induced with all-trans retinoic acid on embryonic day 10 in rats,and the spatiotemporal expression of LIFR was investigated in spina bifida aperta rats and healthy rats from embryonic day 11 to 17.Real time-polymerase chain reaction and western blot assay were used to examine mRNA and protein expression of LIFR in healthy control and neural tube defect embryos.Results of the animal experiment demonstrated that expression of LIFR protein and mRNA in the spinal cords of normal rat embryos increased with embryonic development.LIFR was significantly downregulated in the spinal cords of spina bifida aperta rats compared with healthy rats from embryonic days 11 to 17.Immunohistochemical staining showed that the expression of LIFR in placenta and spinal cord in spina bifida aperta rat embryos was decreased compared with that in control embryos at embryonic day 15.Results from human embryo specimens showed that LIFR mRNA expression was significantly down-regulated in spinal cords of human fetuses with neural tube defects compared with normal controls at a gestational age of 24 to 33 weeks.The results were consistent with the down-regulation of LIFR in the animal experiments.Our study revealed spatiotemporal changes in expression of LIFR during embryonic neurulation.Thus,LIFR might play a specific role in neural tube development.All animal and human experimental procedures were approved by the Medical Ethics Committee of Shengjing Hospital of China Medical University,China(approval No.2016PS106K)on February 25,2016. 展开更多
关键词 amniotic fluid DEVELOPMENT EMBRYOGENESIS LEUKEMIA INHIBITORY factor receptor nerve regeneration neural tube defect PLACENTA SPATIOTEMPORAL expression spina bifida aperta spinal cord serum
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Cerebrospinal fluid neurogranin as a new player in prion disease diagnosis and prognosis 预览
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作者 Anna Villar-Piqué Inga Zerr Franc Llorens 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第5期861-862,共2页
Neurogranin (Ng) and its role as Alzheimer’s disease (AD) biomarker: Ng is a calmodulin-binding protein mainly expressed in cerebral structures such as the cortex,hippocampus and striatum.It is mainly located in the ... Neurogranin (Ng) and its role as Alzheimer’s disease (AD) biomarker: Ng is a calmodulin-binding protein mainly expressed in cerebral structures such as the cortex,hippocampus and striatum.It is mainly located in the dendritic processes,particularly in post-synaptic compartments,but also in the cytosolic compartment,being likely involved in the regulation of the intracellular calcium-calmodulin signaling pathway (Represa et al.,1990).In the last decade,a plethora of studies have demonstrated that cerebrospinal fluid (CSF) Ng is increased in AD patients and in individuals with an ADlike CSF profile (Kester et al.,2015a).This increase seems to be disease-specific because other neurodegenerative conditions including frontotemporal dementia,Lewy body dementia,Parkinson’s disease,progressive supranuclear palsy,multiple system atrophy or Huntington’s disease,present CSF Ng concentrations similar to controls (Wellington et al.,2016).Ng levels in CSF appear to be elevated in mild cognitive impairment (MCI)-affected individuals who progress to AD and are highly related to memory and cognitive function (Kester et al.,2015a;Tarawneh et al.,2016),which indicates that this protein may serve as an early AD biomarker with diagnostic utility in pre-dementia disease stages,and with prognostic utility to predict cognitive decline and MCI-to-AD conversion. 展开更多
关键词 Represa CEREBROSPINAL FLUID MULTIPLE SYSTEM
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Fluid Inclusion and H-O Isotope Geochemistry of the Phapon Gold Deposit, NW Laos: Implications for Fluid Source and Ore Genesis
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作者 Linnan Guo Shusheng Liu +6 位作者 Lin Hou Jieting Wang Meifeng Shi Qiming Zhang Fei Nie Yongfei Yang Zhimin Peng 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第1期80-94,共15页
The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brit... The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brittle fault system. There are three types of primary ore including auriferous calcite vein type, disseminated type, and breccia type, and the first two are important in the Phapon gold deposit. Based on fluid inclusion petrography and microthermometry, three types of primary fluid inclusions including type 1 liquid-rich aqueous, type 2 vapor-rich aqueous and type 3 daughter mineralbearing aqueous were identified in hydrothermal calcite grains. The ore-forming fluids are normally homogeneous, as indicated by the widespread type 1 inclusions with identical composition. The coexistence of type 1 and type 2 inclusions, showing similar final homogenization temperature but different compositions, indicate that fluid immiscibility did locally take place in both two types of ores. The results of microthermometry and H-O isotopes geochemistry indicate that there are little differences on ore-fluid geochemistry between the auriferous calcite vein-type and disseminated type ores. The oreforming fluids are characterized by medium-low temperatures(157–268 oC) and low salinity(1.6 wt.%–9.9 wt.% NaCl eq.). It is likely to have a metamorphic-dominant mixed source, which could be associated with dehydration and decarbonisation of Lower Permian limestone and Middle–Upper Triassic sandstones during the dynamic metamorphism. The fluid-wallrock interaction played a major role, and the locally occurred fluid-immiscible processes played a subordinate role in gold precipitation. Combined with the regional and ore deposit geology, and ore-fluid geochemistry, we suggest that the Phapon gold deposit is best considered to be a member of the epizonal orogenic deposit class. 展开更多
关键词 FLUID inclusion H-O isotopes FLUID SOURCE ore genesis Phapon gold deposit northern Laos
Supercritical Fluid Media in Challenges of Substance and Material Dispersion
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作者 KHAIRUTDINOV Vener GUMEROV Farid KHABRIEV Ilnar 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期519-546,共28页
The paper deals with the problem of material dispersion using supercritical fluid media. At the same time, emphasis is made on modifications(SAS, GAS, SEDS and ASES) of the supercritical fluid anti-solvent method of d... The paper deals with the problem of material dispersion using supercritical fluid media. At the same time, emphasis is made on modifications(SAS, GAS, SEDS and ASES) of the supercritical fluid anti-solvent method of dispersion. The results of SAS method implementation for dispersion of pure polycarbonate and polycarbonate doped with "CdSe/CdS-core/shell" quantum dots(carried out in the pressure range of 8.0-25.0 MPa at temperatures of 313.15 K and 358.15 K) are submitted. The range of the operating parameters has been established through the example of pure polycarbonate dispersion, which provides the production of nanoparticles with the size range of 10-100 nm. Encapsulation of Cd Se/Cd S quantum dots into polycarbonate using the SAS method has no effect on optical properties of the encapsulated quantum dots. The results of paracetamol dispersion using the SEDS method are presented. The effect of operating conditions of the paracetamol dispersion process on morphology of the obtained product is described. Co-dispersion of ethylene–vinyl acetate copolymers and low-density polyethylene mixtures by SEDS method has been carried out under pressures of 8.0-25.0 MPa at temperatures of 313 K, 323 K, and 333 K. The comparison of melting and crystallization between the resulting copolymer mixtures and mixtures with the same composition obtained by mixing in the liquid melt, has shown that implementation of SEDS results in an increase of crystallinity degree of the polymer mixtures. 展开更多
关键词 SUPERCRITICAL FLUID MEDIA SUPERCRITICAL FLUID ANTI-SOLVENT method dispersion POLYCARBONATE PARACETAMOL ethylene-vinyl acetate copolymers
《黄帝内经》“膀胱”概念解析 预览
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作者 王燕平 张维波 +1 位作者 李宏彦 叶丰瑶 《中医学报》 CAS 2019年第1期9-14,共6页
《黄帝内经》中'膀胱'在结构上是指下焦之下、以腹膜为其外壁的盆腔空间,其中包括含尿液的尿脬和腹腔液。'膀胱'所藏津液主要指腹腔液,它来自大肠、小肠分泌的水液,通过三焦特别是下焦的网膜结构聚积于盆腔的间隙空间中... 《黄帝内经》中'膀胱'在结构上是指下焦之下、以腹膜为其外壁的盆腔空间,其中包括含尿液的尿脬和腹腔液。'膀胱'所藏津液主要指腹腔液,它来自大肠、小肠分泌的水液,通过三焦特别是下焦的网膜结构聚积于盆腔的间隙空间中,再通过内脏的温度、压力等作用,变成小水颗粒,从腹膜等途径渗入膀胱经,最后通过膀胱经的气化作用转运全身。故不应把《黄帝内经》中的'膀胱'与西医解剖同名之'膀胱'混为一谈。 展开更多
关键词 “膀胱” 《黄帝内经》 津液 腹腔液
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Global Regularity of Solutions for a One-dimensional Nuclear Fluid with Non-monotone Pressure
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作者 Bao-wei FENG 《应用数学学报:英文版》 CSCD 2019年第4期798-811,共14页
We consider a one-dimensional continuous thermal model of nuclear matter, which is described by a compressible Navier-Stokes-Poission system with a non-monotone equation of state owing to the effective Skyrme nuclear ... We consider a one-dimensional continuous thermal model of nuclear matter, which is described by a compressible Navier-Stokes-Poission system with a non-monotone equation of state owing to the effective Skyrme nuclear interaction between particles. We prove the global existence of solutions in H~4 space for a free boundary value problem with a possible destabilizing influence of the pressure which is not always positive,provided a sufficient thermal dissipation is present and first obtain the existence of classical solutions. 展开更多
关键词 GLOBAL existence COMPRESSIBLE FLUID non-monotone FLUID
SOME PROBLEMS IN RADIATION TRANSPORT FLUID MECHANICS AND QUANTUM FLUID MECHANICS
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作者 Boling Guo Jun Wu 《应用数学年刊:英文版》 2019年第2期111-125,共15页
We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport flu... We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport fluid mechanics equations under certain initial and boundary values. In addition, we also obtain the periodic region problem of the compressible N-S equation with quantum effect has weak solutions under some conditions. 展开更多
关键词 RADIATION transport equation RADIATION FLUID MECHANICS EQUATIONS FLUID MECHANICS EQUATIONS with QUANTUM effects
Diffraction of Surface Harmonic Viscoelastic Waves on a Multilayer Cylinder with a Liquid 预览
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作者 Safarov Ismoil Ibrohimovich Kulmuratov Nurillo Rakhimovich +1 位作者 Teshayev Muhsin Khudoyberdiyevich Kuldashov Nasriddin Urinovich 《应用数学(英文)》 2019年第6期468-484,共17页
An infinitely long circular cylinder, consisting generally of a finite number of coaxial viscoelastic layers, surrounded by a deformable medium is considered. The dynamic stress—the deformed state of a piecewise-homo... An infinitely long circular cylinder, consisting generally of a finite number of coaxial viscoelastic layers, surrounded by a deformable medium is considered. The dynamic stress—the deformed state of a piecewise-homogeneous cylindrical layer from a harmonic wave is investigated. The numerical results of stress, depending on the wavelength are obtained. 展开更多
关键词 VISCOELASTICITY Fluid Frequency Longitudinal and TRANSVERSE Wave Shell Plane Strain
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Numerical optimisation and experimental validation of divided rail freight brake disc crown 预览
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作者 Uros Grivc David Derzic Simon Muhic 《现代交通学报:英文版》 2019年第1期1-10,共10页
In this study,numerical optimisation and experimental validation of a divided rail freight brake disc crown made of grey cast iron EN-GJL-250 is presented.The analysed brake disc is used in rail freight wagons and pos... In this study,numerical optimisation and experimental validation of a divided rail freight brake disc crown made of grey cast iron EN-GJL-250 is presented.The analysed brake disc is used in rail freight wagons and possesses a load capacity of 22.5 tons per axle.Two of the divided rail freight brake discs are mounted on each axle.With the aid of numerical analysis,the thermal dissipation properties of the brake disc were optimised and ventilation losses were reduced,and the numerical results were compared with experimental results.A one-way fluid–structure interaction analysis was performed.A computational fluid dynamic model of a divided rail freight brake disc,used to predict air flow properties and heat convection,was incorporated into a finite element model of the disc and used to evaluate the temperature of the disc.A numerical parametrical optimisation of cooling ribs of the brake disc was also performed,and novel optimised cooling ribs were developed.A transient thermal numerical analysis of the brake disc was validated using temperature measurements obtained during a braking test on a test bench.The ventilation losses of the brake disc were measured on a test bench specifically designed for the task,and the losses were compared to the simulation results.The experimentally obtained ventilation losses and temperature measurements compared favourably with the simulation results,confirming that this type of simulation process may be confidently applied in the future.Through systematic optimisation of the divided rail freight brake disc,ventilation losses were reduced by 37% and the mass was reduced by 21%,resulting in better thermal performance that will bring with it substantial energy savings. 展开更多
关键词 Divided RAIL FREIGHT BRAKE DISC Computational fluid dynamics Finite element method COMPUTER-AIDED engineering One-way fluid-structure interaction
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Wave Propagation in Submerged Pipe Conveying Fluid
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作者 Qing-tian Deng Zhi-chun Yang 《固体力学学报:英文版》 SCIE EI CSCD 2019年第4期483-498,共16页
A problem of wave propagation in submerged pipe conveying fluid is discussed in this paper. Three different fluid-pipe models are considered: the pipe conveying non-viscous fluid immersed in still fluid, the pipe conv... A problem of wave propagation in submerged pipe conveying fluid is discussed in this paper. Three different fluid-pipe models are considered: the pipe conveying non-viscous fluid immersed in still fluid, the pipe conveying non-viscous fluid considering hydrostatic pressure and the pipe conveying viscous fluid considering hydrostatic pressure. The Fliiggle shell model and the hydrostatic pressure considered as the static prestress are introduced for the description of pipe and external/internal fluids. The effects of steady viscous forces are obtained by using the time-mean Navier-Stokes equations, and the perturbation pressures can be determined by means of potential flow theory. The wave dispersion curves of a submerged pipe conveying fluid are obtained numerically by considering the coupling conditions. The effects of internal fluid velocity and hydrostatic pressure on phase velocity are also discussed. 展开更多
关键词 Wave propagation SUBMERGED pipe HYDROSTATIC pressure Shell theory CONVEYING FLUID VISCOUS FLUID
超临界流体色谱在纺织检测中的应用
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作者 郑环达 钟毅 毛志平 《上海纺织科技》 北大核心 2019年第6期1-3,31共4页
随着对纺织品可能带来的环境与生物危害性的日益关注,建立快速响应、高灵敏度的测试分析方法成为纺织产业新的诉求。超临界流体色谱以超临界流体和少量助溶剂为流动相,基于不同化合物在两相间的各异分配系数进行物质分离,其兼具气相色... 随着对纺织品可能带来的环境与生物危害性的日益关注,建立快速响应、高灵敏度的测试分析方法成为纺织产业新的诉求。超临界流体色谱以超临界流体和少量助溶剂为流动相,基于不同化合物在两相间的各异分配系数进行物质分离,其兼具气相色谱和液相色谱的优点,并具有黏度低、传质性好和绿色环保的优势,在低挥发性物质的分析分离上发挥了重要作用。从系统构成、流动相、固定相方面对超临界流体色谱进行了系统介绍。同时,综述了超临界流体色谱在纺织品中致敏染料、聚合物添加剂、荧光增白剂等检测中的应用。 展开更多
关键词 流体 超临界流体 色谱 染料 添加剂 荧光增白剂 纺织品检测
Selection and Evaluation of Dry and Isentropic Organic Working Fluids Used in Organic Rankine Cycle Based on the Turning Point on Their Saturated Vapor Curves
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作者 ZHANG Xinxin ZHANG Congtian +1 位作者 HE Maogang WANG Jingfu 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期643-658,共16页
The organic Rankine cycle(ORC)is a popular technique used in the utilization of low-grade thermal energy.Among wet,dry,and isentropic organic working fluids,the latter two types are more appropriate for ORC systems.In... The organic Rankine cycle(ORC)is a popular technique used in the utilization of low-grade thermal energy.Among wet,dry,and isentropic organic working fluids,the latter two types are more appropriate for ORC systems.In this paper,the definition of turning point on saturated vapor curve of dry fluid and isentropic fluid was given according to the shape of the saturated curve of working fluids in a T-s diagram.On this basis,the model of near-critical region triangle was established.Using this model,the thermodynamic performance of 57 kinds of dry and isentropic organic working fluids in ORC was evaluated.The performance includes the relation between turning point temperature and cycle thermal efficiency,the relation between near-critical region triangle area and cycle thermal efficiency,the relation between near-critical region triangle area and exergy at turning point temperature,the relation between near-critical region triangle area and reciprocal value of slope of saturated vapor curve.Moreover,working fluid selection was also conducted in terms of heat source type.It was found through theoretical analysis results that the popular R123 is an acceptable choice especially for the utilization of closed type heat source.Considering it will be phased out in near future,then cis-butene,butane,trans-butene,and isobutene are worth studying as its successor.Dodecane is worthy of attention and further research and it can be a good choice for utilization of open type heat source. 展开更多
关键词 DRY FLUID ISENTROPIC FLUID turning point saturated vapor curve NEAR-CRITICAL region TRIANGLE ORGANIC Rankine Cycle
Simultaneous determination of amino acids in different teas using supercritical fluid chromatography coupled with single quadrupole mass spectrometry 预览
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作者 Yang Huang Tiejie Wang +2 位作者 Marianne Fillet Jacques Crommen Zhengjin Jiang 《药物分析学报:英文版》 CAS CSCD 2019年第4期254-258,共5页
Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry... Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties. 展开更多
关键词 Amino ACIDS TEAS SUPERCRITICAL fluid chromatography with SINGLE QUADRUPOLE mass spectrometry (SFCMS)
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Mixture flow of particles and power-law fluid in round peristaltic tube 预览
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作者 Hailin YANG Jianzhong LIN Xiaoke KU 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第6期805-822,共18页
The erythrocyte and blood flowing in the blood vessel can be treated as the two-phase flow of the mixture of particles and a power-law fluid in a peristaltic tube.In the present work, the peristaltic transport of a po... The erythrocyte and blood flowing in the blood vessel can be treated as the two-phase flow of the mixture of particles and a power-law fluid in a peristaltic tube.In the present work, the peristaltic transport of a power-law fluid and the suspension of particles in a tube is investigated by a perturbation method using the long wavelength approximation. The influence of different parameters on the velocity profile and streamlines is explored. Results show that there is a deflection of the flow field when the power-law index n = 0.5 or 1.5 compared with the Newtonian fluid where the trapping zone is symmetric to a certain cross section. The flux rate and reflux of the material are identified,and the conditions under which the reflux appears are determined. Moreover, a reflux phenomenon occurs near the wall. The trapping zone is related to not only the tube geometry and the flow flux but also the fluid properties. Both the length and width of the trapping zone increase with an increase in θ or φ. The trapping zone is more difficult to produce in the shear-thinning fluid than the shear-thickening fluid. 展开更多
关键词 peristaltic transport TWO-PHASE FLOW POWER-LAW fluid PERTURBATION method TRAPPING phenomenon
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Stamping Reliability of Rocket Engine Cover Based on Finite Element Anglysis and Experiments 预览
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作者 高辉 丁凡 +2 位作者 杨涛 侯守全 张斌斌 《东华大学学报:英文版》 EI CAS 2019年第3期255-260,共6页
This paper mainly focuses on the simulation and experimental study of the reliability of the solid rocket nozzle cover.The test-bed is designed according to the technical requirements in order to provide different sta... This paper mainly focuses on the simulation and experimental study of the reliability of the solid rocket nozzle cover.The test-bed is designed according to the technical requirements in order to provide different stamping rates and tests for different sizes of covers.The gas source,the four valves and the installation container structure are used to realize the stamping.The installation container is a multistage flange stacking structure to achieve the installation of different sizes of plugging covers,and then the opening process of the plugging cover is recorded by the high speed pressure sensor and the automatic control system.The fluid solid coupling method is used to simulate the impact state of plugging cover in the flow field at 10,20,30 and 35 ms,and the maximum pressure at 35 ms is 1.244 MPa.Then the deformation of aluminum alloy plugging cover is observed by stress analysis and display dynamic method.The maximum value of Von Mises Stress of the simulation result is 277.600 MPa.In the experimental test,the performance of the system is tested with a high strength plugging cover.In the opening state of the two large flux control valves,the pressure in the installation container reaches 1.000 MPa at 35 ms.And then we modify the experimental system with the knowledge of aerodynamic theory.Finally,the plugging cover is installed to carry out the experiment,so as to obtain the reliable stamping rate of the plugging cover.Simulations,blind measurements and measurement results provide strong data for reliability of the plugging cover opening,and provide reliable reference data for rocket engine charge structure and nozzle shape optimization. 展开更多
关键词 plugging COVER STAMPING RELIABILITY simulation FLUID solid coupling
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Geology, Mineralization, Fluid Inclusion and Stable Isotope of the Early Cretaceous Sn and Associated Metal Deposits in the Southern Great Xing’an Range, NE China: A Review 预览
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作者 WANG Chengyang LIU Guanghu +3 位作者 SUN Zhenjun LIU Jie LI Jianfeng LIANG Xinyang 《地质学报:英文版》 SCIE CAS CSCD 2019年第5期1522-1543,共22页
The Southern Great Xing’an Range(SGXR) hosts a number of Early Cretaceous Sn and associated metal deposits, which can be divided into three principal types according to their geological characteristics: skarn type de... The Southern Great Xing’an Range(SGXR) hosts a number of Early Cretaceous Sn and associated metal deposits, which can be divided into three principal types according to their geological characteristics: skarn type deposits, porphyry type deposits and hydrothermal vein type deposits. Fluid inclusion assemblages of different types of deposits are quite different, which represent the complexities of metallogenic process and formation mechanism. CH4 and CO2 have been detected in fluid inclusions from some of deposits, indicating that the ore-forming fluids are affected by materials of Permian strata. Hydrogen and oxygen isotope data from ore minerals and associated gangue minerals indicate that the initial ore fluids were dominated by magmatic waters, some of which had clearly exchanged oxygen with wall rocks during their passage through the strata. The narrow range for the δ34S values presumably reflects the corresponding uniformity of the ore forming fluids, and these δ34S values have been interpreted to reflect magmatic sources for the sulfur. The comparation between lead isotope ratios of ore minerals and different geological units’ also reveals that deeply seated magma has been a significant source of lead in the ores. 展开更多
关键词 fluid inclusion stable isotope Early Cretaceous SN and ASSOCIATED metal deposits Southern GREAT Xing'an RANGE
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Magma chamber growth models in the upper crust: A review of the hydraulic and inertial constraints 预览
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作者 Eugenio Aragon Fernando J. D'Eramo +4 位作者 Lucio P. Pinotti Manuel Demartis Jose Maria Tubia Roberto F. Weinberg Jorge E. Coniglio 《地学前缘:英文版》 CAS CSCD 2019年第3期1211-1218,共8页
Finite volumes of magma moving in confinement, store hydraulic potential energy for the generation, control and transmission of power. The Pascal’s principle in a hydraulic jack arrangement is used to model the verti... Finite volumes of magma moving in confinement, store hydraulic potential energy for the generation, control and transmission of power. The Pascal’s principle in a hydraulic jack arrangement is used to model the vertical and lateral growth of sills. The small input piston of the hydraulic jack is equivalent to the feeder dike, the upper large expansible piston equivalent to the magmatic chamber and the inertial force of the magma in the dike is the input force. This arrangement is particularly relevant to the case of sills expanding with blunt tips, for which rapid fracture propagation is inhibited. Hydraulic models concur with experimental data that show that lateral expansion of magma into a sill is promoted when the vertical ascent of magma through a feeder dike reaches the bottom contact with an overlying, flat rigid-layer. At this point, the magma is forced to decelerate, triggering a pressure wave through the conduit caused by the continued ascent of magma further down (fluid-hammer effect). This pressure wave can provide overpressure enough to trigger the initial hydraulic lateral expansion of magma into an incipient sill, and still have enough input inertial force left to continue feeding the hydraulic system. The lateral expansion underneath the strong impeding layer, causes an area increase and thus, further hydraulic amplification of the input inertial force on the sides and roof of the incipient sill, triggering further expansion in a self-reinforcing process. Initially, the lateral pressure increase is larger than that in the roof allowing the sill to expand. However, expansion eventually increases the total integrated force on the roof allowing its uplift into either a laccolith, if the roof preserves continuity, or into a piston bounded by a circular set of fractures. Hydraulic models for shallow magmatic chambers, also suggest that laccolith-like intrusions require the existence of a self-supported chamber roof. In contrast, if the roof of magmatic chambers loses the self-supporting capacity, lop 展开更多
关键词 Pascal’s principle GEOLOGIC HYDRAULIC jack EMPLACEMENT SILLS growth Fluid HAMMER
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Hydrodynamics Analysis of Automatic Feeding and Forming System of Coating Layer 预览
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作者 张斌斌 杨涛 +2 位作者 李继良 丁凡 陈强 《东华大学学报:英文版》 EI CAS 2019年第3期277-283,共7页
The automatic forming device of the cladding layer of the solid rocket engine is a kind of equipment that can automatically complete the coating process of the coating layer.It is mainly composed of the feeding system... The automatic forming device of the cladding layer of the solid rocket engine is a kind of equipment that can automatically complete the coating process of the coating layer.It is mainly composed of the feeding system,the detection system and the automatic control system.The feeding system plays the role of providing the slurry in the coating process.In order to ensure the uniformity and stability of the feeding device,the automatic forming and feeding system of the coating is studied in this paper.The dynamic analysis of the slurry transportation process in the automatic coating system is carried out.In this paper,the feed cylinder is designed in theory.The feeding mode of the servo electric cylinder is adopted.Through the analysis of the hydrodynamic equations,the mixture model is chosen as the basis for the numerical simulation analysis.We use the SolidWorks software to create the geometric model of the feed cylinder.The dynamic analysis of the feed cylinder is carried out by Fluent software,and the convergent residual diagram and the fluid cloud chart are obtained.Fluent software is used for simulation analysis.The simulation results show that the distribution device has stable flow velocity and uniform slurry flow in the feeding process.The effect of scraping and coating process can be guaranteed by the feeding device,which provides a theoretical basis for actual production. 展开更多
关键词 SCRAPING and coating FEED FEEDING SYSTEM fluid mechanics fluent simulation analysis
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Comparison of the Efficacy of Standard Decompressive Craniectomy Combined with Cerebrospinal Fluid Circulation Reconstruction in the Treatment of Severe Craniocerebral Injury 预览
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作者 Zhanqing Han Jianbin Sun Jingyang Zhong 《临床护理研究》 2019年第2期11-13,共3页
Objective:To observe and discuss the clinical effect of standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction in the treatment of severe craniocerebral injury.Methods:Seventy ... Objective:To observe and discuss the clinical effect of standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction in the treatment of severe craniocerebral injury.Methods:Seventy patients who underwent surgery in our hospital were selected as subjects for this study.The time was from August 2016 to August 2018,and patients were divided into experimental group(35 cases)and control group(35 cases)according to the random number table method.The control group was treated with a single standard decompressive craniectomy according to clinical symptoms.The experimental group was treated with standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction.The surgical treatment effect,GCS(Glasgow Coma Scale)score and operation time were compared between the two groups.Results:After comparison,the surgical treatment effect of the experimental group was higher than that of the control group and there was a significant difference between the two groups(P<0.05).The GCS score and operation time of the experimental group were also better than of the control group and there was a significant difference the two groups(P<0.05).Conclusion:The use of standard decompressive craniectomy combined with cerebrospinal fluid circulation reconstruction in the treatment of severe craniocerebral injury is more effective and worthy of widespread promotion and application. 展开更多
关键词 standard decompressive craniectomy cerebrospinal fluid circulation reconstruction severe craniocerebral injury combined therapy
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