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Large post-liquefaction deformation of sand:Mechanisms and modeling considering water absorption in shearing and seismic wave conditions

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Underground Space 2024年第5期18卷 3-64页

作者： jian-min zhang Rui Wang Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China

Large deformation of sand due to soil liquefaction is a major cause for seismic *** this study,the mechanisms and modeling of large post-liquefaction deformation of sand considering the significant influence of water absorption in shearing and seismic wave *** of case histories from past earthquakes and review of existing studies highlight the importance of the two *** on the micro and macro scale mechanisms for post-liquefaction shear deformation,the mechanism for water absorption in shearing after initial liquefaction is *** is aided by novel designed constant water-absorption-rate shear *** absorption in shearing can be classified into three types,including partial water absorption,complete water absorption,and compulsory water *** the influence of water absorption in shearing,even a strongly dilative sand under naturally drained conditions could experience instability and large shear *** mechanism for amplification of post-liquefaction deformation under surface wave load is also explained via element tests and theoretical *** shows that surface wave–shear wave coupling can induce asymmetrical force and resistance in sand,resulting in asymmetrical accumulation of deformation,which is amplified by liquefaction.A constitutive model,referred to as CycLiq,is formulated to capture the large deformation of sand considering water absorption in shearing and seismic wave conditions,along with its numerical implementation *** model is comprehensively calibrated based on various types of element tests and validated against centrifuge shaking table tests in the liquefaction experiments and analysis projects(LEAP).The model,along with various numerical analysis methods,is adopted in the successful simulation of water absorption in shearing and Rayleigh wave-shear wave coupling induced large liquefaction ***,the model is applied to high-performance simulation fo

关键词： Liquefaction Sand Large deformation Water absorption in shearing Surface wave Rayleigh wave-shear wave coupling

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A constrained neural network model for soil liquefaction assessment with global applicability

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1066-1082页

作者： Yifan zhang Rui WANG jian-min zhang jianhong zhang Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China

A constrained back propagation neural network(C-BPNN)model for standard penetration test based soil liquefaction assessment with global applicability is developed,incorporating existing knowledge for liquefaction triggering mechanism and empirical *** its development and validation,a comprehensive liquefaction data set is compiled,covering more than 600 liquefaction sites from 36 earthquakes in 10 countries over 50 years with 13 complete information *** C-BPNN model design procedure for liquefaction assessment is established by considering appropriate constraints,input data selection,and computation and calibration *** empirical relationships for overburden correction and fines content adjustment are shown to be able to improve the prediction success rate of the neural network model,and are thus adopted as constraints for the C-BPNN *** effectiveness of the C-BPNN method is validated using the liquefaction data set and compared with that of several liquefaction assessment methods currently adopted in engineering *** C-BPNN liquefaction model is shown to have improved prediction accuracy and high global adaptability.

关键词： soil liquefaction assessment case history dataset constrained neural network model existing knowledge

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Experimental study of anti-cavitation mechanism of valve lintel natural aeration of high head lock

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Journal of Hydrodynamics 2020年第2期32卷 337-344页

作者： Xin Wang Ya-an Hu jian-min zhang Hydraulic Engineering Department Nanjing Hydraulic Research InstituteNanjing210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing210029China

To study the serious valve top gap cavitation of Datengxia high head single-lift ship lock,the 1:1 scale slice experiment is carried out,to truly reveal the gap flow characteristics,as well as the valve top gap cavitation characteristics and the anti-cavitation mechanism of natural *** kinds of cavitation,namely,the throat cavitation,the mainstream inner cavitation,and the valve plate cavitation,are determined and they are found to occur step-by-step in the gap section in the development of the *** to the anti-cavitation mechanism of the natural aeration,the pressure of the gap flow through the ventilation is increased,to avoid the mainstream inner cavitation and the valve plate cavitation,and to weaken the throat *** negative pressure zone in the gap section gradually extends with the development of the cavitation until the gap section is filled with a stable−10 m water *** the natural aeration measure is employed,the pressure in the gap section approximately reaches the−2 m water head,and the cavitation *** systematic tests reveal the quadratic polynomial relationship between the pressure in the gap and the ventilation per meter *** pressure,which corresponds to the maximum value of the ventilation at the beginning of the gap,approximately reaches the−2 m water head,and the pressure and the ventilation reach the equilibrium state *** the pressure in the gap increases when the valve is opened,the ventilation gradually decreases until the natural aeration *** gap section length for the high head valves has a great effect on the natural aeration and should be long enough to maintain the stable negative pressure in the gap,whereas the throat width has a minimal *** can be used for the anti-cavitation design of the high head lock valve.

关键词： High head lock valve top gap cavitation natural aeration slice experiment

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A REAL-TIME AFM STUDY ON CRYSTAL NUCLEATION AND GROWTH IN NANODROPLETS OF ISOTACTIC POLYPROPYLENE

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Chinese Journal of Polymer Science 2013年第9期31卷 1310-1320页

作者： Jun-chai Zhao Bo Xing Zheng Peng jian-min zhang School of Material Science and Engineering Shijiazhuang Tiedao University

Isotactic polypropylene （iPP） nanodroplets were prepared by using the classical droplet method in this study. The formation of nanodroplets allowed the controlled observation of polymer nucleation as well as access to crystal growth at exceptionally high supercooling in /PP. Three cases including the heterogeneous nucleation and fast crystallization in iPP droplets, the formation of multiple independent homogeneous nuclei within a single droplet and a single nucleus within a single droplet were detected by using atomic force microscopy （AFM） during gradually cooling after remelting the nanodroplets. Moreover, it is found that when the volume of droplet is larger than the value of ca. 130000 nm3, the first case was observed. Otherwise, the latter two cases appeared. The temperature at which the onset of nucleation was observed in individual droplets was found to be mainly dependent on height of the droplets when the size scale of the droplet is comparable to the size of the critical nucleus in at least one dimension, which indicates the nucleation behavior under confinement.

关键词： Atomic force microscopy (AFM) Isotactic polypropylene (iPP) Nanodroplets Homogeneous nucleation.

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Case Report:Granulomatous hypophysitis:two case reports and literature review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 552-558页

作者： jian SHI jian-min zhang Qun WU Gao CHEN Hong zhang Wen-liang BO Department of Neurosurgepy the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Neurosurgery Suichang People's Hospital Suichang 323000 China

Granulomatous hypophysitis （GRH） is extremely rare and commonly presents with chronic inflammatory of the enlarged pituitary gland. In our study, 66-year-old and 57-year-old women, both Chinese, were diagnosed with GRH presenting preoperatively definite imageology characters as pituitary adenoma. The 66-year-old woman presented with a year of headache, half a year of gradual decrease of visual acuity, and one month of right ptosis. Serum prolaetin level was slightly elevated. Screening computed tomography （CT） scanning revealed typical low density mass found on the enlarged sella, which demonstrated invasive extension from the sella to the right cavernous sinus by contrast enhanced magnetic resonance imaging （MRI）. Consequently, the patient was diagnosed with probable invasive pituitary adenoma. The other 57-year-old woman complained a light headache and had been previously treated as nonfunctional pituitary adenoma in other hospital. Finally these two patients underwent transsphenoidal microsurgery and were diagnosed with GRH according to postoperative histopathology. They then were treated with steroid. During the follow-up, the clinical symptoms such as headache, visual damage, and ptosis vanished, and the mass of the sellae dramatically shrank on repeated MR images. Clinically and radiologically, GRH is a rare sellar entity easily to be misdiagnosed as a pituitary adenoma. Trans-sphenoidal surgery can decompress the optical nerve or oculomotornerve as a therapeutic strategy, and support biopsy or further pathological diagnosis. However, the hormonal therapy should be emphasized both as diagnostic and therapeutic strategies. Conservative and tentative steroid treatment should be performed in preoperative period without acute nerve damage.

关键词： Granulomatous hypophysitis Steroid treatment Imageology Trans-sphenoidal surgery

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VIBRATION OF A SINGLE PROTEIN BUBBLE IN BINGHAM LIQUID

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Journal of Hydrodynamics 2009年第5期21卷 658-668页

作者： WANG Hai-min jianG Xu-ping MA jian-min zhang Wen College of Power Engineering University of Shanghai for Science and Technology Shanghai 200093 China Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

The vibration of a single protein bubble may take place under the action of high pressure difference. In this process, the bubble wall may experience a finite deformation. The equation describing the dynamics of the protein bubble with viscoelastic film in Bingham liquid is derived. A numerical solution to this equation is carried out to study the effect of liquid pressure, the characteristic parameters of Bingham liquid and the viscosity of the protein film on the finite deformation of the bubble. The results show that the vibration of the protein bubble wall is caused by the action of pressure difference, the elastic stress in finite deformation and the dissipation of viscosity of the protein film and Bingham liquid. The vibration is nonlinear. Decreasing the pressure difference between gas and Bingham liquid on both sides of the protein bubble will lead to a change of vibration performance. The frequency and amplitude are reduced, tegether with the speed of vibration damping. In addition, the deformation rate of the bubble is smaller when the amplitude of vibration is reduced, which means shorter time to reach a balance state. On the other side, the increase of the magnitude of viscosity of the protein film or the plastic viscosity of Bingham liquid can restrain the vibration of the protein bubble wall in the course of finite deformation, as a result, the load bearing capacity of bubble is enhanced.

关键词： protein bubble Bingham liquid vibration finite deformation viscosity

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Analysis on Genetic Relationship of Oxya chinensis and Oxya japonica from Xuzhou and Pingshan, China

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Agricultural Sciences in China 2006年第2期5卷 116-122页

作者： zhang jian-zhen zhang min GUO Ya-ping MA En-bo College of Life Science and Technology Shanxi University Taiyuan 030006 P.R.China

Genetic relationship among Oxya chinensis populations and Oxya japonica populations collected from Xuzhou City, jiangsu Province and Pingshan County, Hebei Province, China were analyzed by random amplified polymorphic DNA （RAPD） markers. A total of 125 DNA bands ranging from 200 to 2 200 bp were amplified by 10 random primers in DNA samples from 43 grasshopper individuals. One hundred and twenty-three （99%） of these bands were polymorphic. Shannon＇s index showed that the genetic, diversity within O. chinensis （0.3432） was higher than that of O. japonica （0.2781）. Nei＇s genetic distance between O. chinensis population and O. japonica population from the same area was less than that between populations from two different areas. The dendrogram based on Nei＇s genetic distance of RAPD markers was constructed using the unweighted pair group method with the arithmetic average （UPGMA） and Neighbor-Joining （NJ） methods. Cluster analysis indicated that all the individuals were grouped into two main clusters. O. chinensis populations from Xuzhou and Pingshan formed one cluster, and O. japonica populations from the two regions belonged to another cluster. The results demonstrated that RAPD can detect within species, and among closely related species. polymorphisms to distinguish minor difference among individuals

关键词： Oxya chinensis Oxya japonica random amplified polymorphic DNA (RAPD) genetic relationship

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B7-H4 expression is elevated in human U251 glioma stem-like cells and is inducible in monocytes cultured with U251 stem-like cell conditioned medium

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Chinese Journal of Cancer 2013年第12期32卷 653-660页

作者： Lian-Jie Mo Hong-Xing Ye Ying Mao Yu Yao jian-min zhang Department of Neurosurgery Second Affiliated Hospital School of Medicine Zhejiang University Department of Neurosurgery Huashan Hospital Fudan University

Previous studies indicated that B7-H4,the youngest B7 family,negatively regulates T cell-mediated immunity and is significantly overexpressed in many human *** stem cells are purported to play a role in tumor renewal and resistance to radiation and ***,the link between B7-H4and tumor stem cells is *** this study,we investigated B7-H4 expression in the medium of human glioma U251 cell *** results showed that U251 cells cultured in serum-free medium(supplemented with 2%B27,20 ng/mL epidermal growth factor,20 ng/mL basic fibroblast growth factor)maintained stem-like cell characteristics,including expression of stem cell marker CD133 and the neural progenitor cell markers nestin and *** contrast,U251 cells cultured in serum-containing medium highly expressed differentiation marker glial fibrillary acidic *** cytometry analysis showed serum-free medium-cultured U251 cells expressed higher intracellular B7-H4 than serumcontaining medium-cultured U251 cells(24%-35%vs.8%-11%,P<0.001).Immunofluorescence in purified monocytes from normal human peripheral blood mononuclear cells revealed moderate expression of B7-H4 after stimulation with conditioned medium from U251 cells cultured in serum-containing ***,conditioned medium from U251 stem-like cells had a significant stimulation effect on B7-H4expression compared with serum-containing conditioned medium(P<0.01).Negative costimulatory molecule B7-H4 was preferentially expressed in U251 stem-like cells,and conditioned medium from these cells more effectively induced monocytes to express B7-H4 than conditioned medium from U251 cells cultured in the presence of *** results show that U251 stem-like cells may play a more crucial role in tumor immunoloregulation with high expression of B7-H4.

关键词：外周血单核细胞肿瘤干细胞条件培养基脑胶质瘤碱性成纤维细胞生长因子诱导无血清培养基 U251细胞

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Hydrogen induced room-temperature ferromagnetism in Co-doped ZnO: first-principles and Monte Carlo study

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Chinese Science Bulletin 2014年第26期59卷 3232-3238页

作者： jian-min zhang Zhigao Chen Kehua Zhong Guigui Xu Zhigao Huang College of Physics and Energy Fujian Normal University Fujian Provincial Key Laboratory of Quantum Manipulation andNew Energy Materials

The structural stability, vibrational and magnetic properties of hydrogen doped ZnO:Co have been studied by first-principles calculations based on density functional theory. Bond-center(BC) sites were identified to be most stable sites for hydrogen, the corresponding vibrational frequencies including anharmonic contributions were calculated. Its magnetic properties were investigated as well. The calculated results reveal that hydrogen could induce the change of electronic transfer, leading to a decrease of magnetic moment. However, the magnetic coupling between Co atoms is greatly strengthen. The results simulated by Monte Carlo method indicate that hydrogen can induce the Curie temperature to increase from 200 to 300 K.

关键词：蒙特卡罗法钴掺杂第一性原理氧化锌铁磁性第一原理计算氢室温

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Predictive significance of serum inhibin B on testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men

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Asian Journal of Andrology 2019年第2期21卷 137-142页

作者： Zhi-Guo Zhu Zhi-Gang Zhao Qing-Yang Pang Tong Chen jian-min zhang Tai-jian zhang Chao Xu Hao-Bo zhang Wen Liu Xu-Jun Xuan Department of Urology and Andrology Minimally Invasive Surgery CenterThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510230China Guangzhou Institute of Urology Guangzhou 510230China Guangdong Key Laboratory of Urology Guangzhou 510230China Center for Reproductive Medicine Shandong UniversityJinan 250001China National Research Center for Assisted Reproductive Technology and Reproductive Genetics Jinan 250001China The Key Laboratory for Reproductive Endocrinology of ministry of Education Jinan 250001China Shandong Xiehe University Jinan 250109China

The purpose of this study was to determine the diagnostic accuracy of serum inhibin B(INHB)as a predictor of the retrieval outcome of testicular haploid gametes(spermatids and testicular spermatozoa)in nonobstructive azoospermic *** hormone levels,testicular volume,and histological evaluation were performed in 403 Chin ese non obstructive azoospermic *** haploid gamete was successfully retrieved in 213 of 403 patients(52.85%).The haploid gamete group always had higher INHB levels than the non-haploid gamete *** to the receiver operating characteristic(ROC)curve analysis,INHB was a good predictor of testicular haploid gamete retrieval outcome in all patients(sensitivity:77.93%and specificity:91.58%)and patients with normal follicle-stimulating hormone(FSH;sensitivity:88.52%and specificity:70.83%).The area under the ROC curve(AUC)of INHB was similar to that of FSH in all patients or patients with normal *** patients with elevated FSH,INHB was superior to FSH in predicting the presence of haploid gamete(AUC:0.73 vs 0.55,P<0.05),with a sensitivity of 60.00%and a specificity of 80.28%.It con eluded that serum INHB as an effective marker for spermatoge nesis was a sign ificant predictor of testicular haploid gamete retrieval outcomes in nonobstructive azoospermic ***,INHB is superior to FSH in predicting the presenee of haploid gamete in the patients with elevated FSH.

关键词： azoospermia biomarker follicle-stimulating hormone inhibin B testicular sperm extraction

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