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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 867-877页

作者： Zhen-jun YANG guo-hua liu College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China

Fully automatic finite element(FE) modelling of the fracture process in quasi-brittle materials such as concrete and rocks and ductile materials such as metals and alloys,is of great significance in assessing structural integrity and presents tre-mendous challenges to the engineering community. One challenge lies in the adoption of an objective and effective crack propagation criterion. This paper proposes a crack propagation criterion based on the principle of energy conservation and the cohesive zone model(CZM) . The virtual crack extension technique is used to calculate the differential terms in the criterion. A fully-automatic discrete crack modelling methodology,integrating the developed criterion,the CZM to model the crack,a simple remeshing procedure to accommodate crack propagation,the J2 flow theory implemented within the incremental plasticity framework to model the ductile materials,and a local arc-length solver to the nonlinear equation system,is developed and im-plemented in an in-house program. Three examples,i.e.,a plain concrete beam with a single shear crack,a reinforced concrete(RC) beam with multiple cracks and a compact-tension steel specimen,are simulated. Good agreement between numerical predictions and experimental data is found,which demonstrates the applicability of the criterion to both quasi-brittle and ductile materials.

关键词： Finite element method (FEM) Crack propagation criterion Cohesive zone model (CZM) Virtual crack extension(VCE) Arc-length method

Cryosphere water resources supply function and service in China

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Advances in Climate Change Research 2022年第3期13卷 408-420页

作者： Kai-Lu LI Ren-Sheng CHEN guo-hua liu Yong YANG Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China College of Urban and Environmental Sciences Northwest UniversityXi’an 710000China

With global warming and rapid shrinkage of the cryosphere,the decreasing cryosphere water resources(CWR)supply function would weaken its service and then affect local economic development and implement of United Nations Sustainable Development Goals(SDGs)in the world,but how does the CWR supply affect its service and their variations in the past and future are still not clear at *** this study,the past dynamics(1960-2020),current situation(2010s)and projected changes(2020-2100)of CWR in China were assessed by calculating the meltwater from glacier,snow cover and the ground ice of permafrost under Representative Concentration Pathways scenarios(RCP2.6,RCP4.5,and RCP8.5).Combined with projected data of population and economy,the CWR service potential was also estimated in the 2030s,2050s and 2090s under scenarios of Shared Socioeconomic Pathways(SSP1,SSP2,and SSP5).The annual CWR in China is about 310.7×10^(9)m^(3) in the 2010s,with glacier runoff,snowmelt,and ground ice meltwater accounting for 24.1%,72.7%and 3.2%,*** SSP1-RCP2.6,the quantity of CWR was projected to decline by 14%-18%over the next 80 years,and the service potential would reach the peak in *** under SSP5-RCP8.5,CWR would be reduced by 40%by 2100,and the service would gradually decline from *** study of CWR is of great significance for water security,sustainable development and risk avoidance in the arid endorheic region.

关键词： Cryosphere water resources Glaciers Snow cover Permafrost Function and service

Imipramine protects retinal ganglion cells from oxidative stress through the tyrosine kinase receptor B signaling pathway

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Neural Regeneration Research 2016年第3期11卷 476-479页

作者： Ming-lei Han guo-hua liu Jin guo Shu-juan Yu Jing huang Department of Ophthalmology Qilu Children HospitalShandong University

Retinal ganglion cell（RGC） degeneration is irreversible in glaucoma and tyrosine kinase receptor B（Trk B）-associated signaling pathways have been implicated in the *** this study,we attempted to examine whether imipramine,a tricyclic antidepressant,may protect hydrogen peroxide（H_2O_2）-induced RGC degeneration through the activation of the Trk B pathway in RGC-5 cell ***-5 cell lines were pre-treated with imipramine 30 minutes before exposure to H_2O_*** blot assay showed that in H_2O_2-damaged RGC-5 cells,imipramine activated Trk B pathways through extracellular signal-regulated protein kinase/Trk B *** staining assay also demonstrated that imipramine ameliorated H_2O_2-induced apoptosis in RGC-5 ***,Trk B-Ig G intervention was able to reverse the protective effect of imipramine on H_2O_2-induced RGC-5 *** therefore protects RGCs from oxidative stress-induced apoptosis through the Trk B signaling pathway.

关键词： nerve regeneration retinal ganglion cell imipramine oxidative stress apoptosis tyrosine kinase receptor B neural regeneration

Synthesis of multi-hydroxyl and sulfonyl dual-functionalized room temperature ionic liquids

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Chinese Chemical Letters 2007年第6期18卷 633-635页

作者： guo Yang Zhu Rong Wang guo hua liu Li Qun Xu Bei Zhang Xia Qin Wu College of Life and Environment Science Shanghai Normal University Shanghai 200234 China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha 410082 China

Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).

关键词： Dual-functionalized Zwitterionic salt Room temperature ionic liquids Polymerization

Immobilization of chiral Rh catalyst on glass and application to asymmetric transfer hydrogenation of aryl ketones in aqueous media

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Chinese Chemical Letters 2014年第4期25卷 613-616页

作者： Tan-Yu Cheng Jing-Lan Zhuang Hui Yao huai-Sheng Zhang guo-hua liu Key Laboratory of Resource Chemistry of Ministry of Education College of Life and Environmental ScienceShanghai Normal University

A chiral catalyst, Cp＊RhTsDPEN （Cp＊ = pentamethyl cyclopentadiene, TsDPEN = substitutive phenylsulfonyl-l,2-diphenylethylenediamine）, was synthesized and immobilized at the surface of glass. The immobilized catalyst exhibited good catalytic efficiency for asymmetric transfer hydrogenation of aromatic ketones in water with HCOONa as hydrogen source.

关键词： Heterogeneous Rh catalyst Asymmetric transfer hydrogenation Aromatic ketones Glass suhstrate

The evolution of refractive status in Chinese infants during the first year of life and its affected factors

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1290-1294页

作者： Shu-Juan Yu guo-hua liu Yi liu Jing huang Ming-Lei Han Bo-dun Zha Zhong-Tao Gai Department of Ophthalmology Qilu Children's Hospital of Shandong University Jinan 250022 Shandong ProvinceChina Pediatric Research Institute Qilu Children's Hospital of Shandong University Jinan 250022 Shandong ProvinceChina Department of Ophthalmology Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021 Shandong Province China

AIM： To study the evolution of the refractive status and examine the affected factors in infants during the first year of life in a large sample size in China. METHODS： A total of 1258 babies （2516 eyes） aged 32wk gestational age to ty participated in the study, including 766 premature and 492 full-term infants. First, each baby received an orthoptic examination, slit-lamp checking and fundus imaging. Patients with diseases which might affect refractive status were excluded from the cohort. The cycloplegia retinoscopy was performed. Their neonatal histories were reviewed. Each measurement contained the refractive status and calculation of the spherical equivalent （SE）. RESULTS： Refractive state showed an average hyperopia of ＋0.94_＋1.63 D at early ages, followed by a trend toward more hyperopia. The refractive state reached the top （＋2.431.46 D） at the age of one to two months. Then gliding till one year old when the refractive state reached ＋0.59：1.41 D. The prevalence of astigmatism was 42.17% in the study, being 2.82% myopic astigmatism and 39.35% hyperopic astigmatism. The 94.1% of hyperopic astigmatism was with-the-rule astigmatism and 71.83% of myopic astigmatism was with-the-rule astigmatism. Refractive state between boys and girls was different. The mean SE of boys was ＋1.97＋1.57 D, while that of girls was ＋1.79＋1.46 D, and the difference was significant. CONCLUSION： Before one year old, the change of refractive status is associated with checking age and sex. At the age of one to two months, the degree of hyperopia reaches the top. Boys have more hyperopic degree than girls, and with- the-rule astigmatism is predominant. Excluding premature infants with advanced retinopathy of prematurity, premature and full-term children have same refraction status.

关键词： refractive status corrected age infant, prematurity spherical equivalent cycloplegic retinoscopy

Experimental study of water effects on gas desorption during highpressure water injection

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 408-413页

作者： ZHANG guo-hua liu Xian-xin BI Ye-wu PU Wen-long Safety Engineering College Heilongliang University of Science and Technology Harbin 150027 China

For the question of applying high-pressure water injection to increase gas extraction efficiency by increasing the permeability of water to drive gas action, an independently designed gas desorption experimental measuring device was used under the condition of external solution invasion. The law of water effect on gas desorption was obtained after water invasion through experiment for the first time. The results show that water＇s later invasion not only can make the quantity of gas dcsorp- tion greatly reduced, but also can make gas desorption end early. Therefore, when evaluating the applications of high-pressure water injection to increase gas extraction efficiency, we should take water damaging effects on gas desorption into account.

关键词： gas desorption gas extraction high pressure water injection later invasion

Toxocariasis:a silent threat with a progressive public health impact

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Infectious Diseases of Poverty 2018年第1期7卷 570-582页

作者： Jia Chen Quan liu guo-hua liu Wen-Bin Zheng Sung-Jong Hong Hiromu Sugiyama Xing-Quan Zhu Hany M.Elsheikha State Key Laboratory of Veterinary Etiological Biology Lanzhou Veterinary Research InstituteChinese Academy of Agricultural Sciences1 XujiapingYanchangbuLanzhouGansu Province 730046People’s Republic of China Ningbo University School of Medicine NingboZhejiang ProvincePeople’s Republic of China Military Veterinary Institute Academy of Military Medical SciencesKey Laboratory of Jilin Province for Zoonosis Prevention and ControlChangchunJilin ProvincePeople’s Republic of China College of Veterinary Medicine Hunan Agricultural UniversityChangshaHunan ProvincePeople’s Republic of China Department of Medical Environmental Biology Chung-Ang University College of MedicineSeoulSouth Korea Department of Parasitology National Institute of Infectious DiseasesTokyoJapan Faculty of Medicine and Health Sciences School of Veterinary Medicine and ScienceUniversity of NottinghamLoughboroughUK

Background:Toxocariasis is a neglected parasitic zoonosis that afflicts millions of the pediatric and adolescent populations worldwide,especially in impoverished *** disease is caused by infection with the larvae of Toxocara canis and ***,the most ubiquitous intestinal nematode parasite in dogs and cats,*** this article,recent advances in the epidemiology,clinical presentation,diagnosis and pharmacotherapies that have been used in the treatment of toxocariasis are *** text:Over the past two decades,we have come far in our understanding of the biology and epidemiology of ***,lack of laboratory infrastructure in some countries,lack of uniform case definitions and limited surveillance infrastructure are some of the challenges that hindered the estimation of global disease *** encompasses four clinical forms:visceral,ocular,covert and *** or misdiagnosis of any of these disabling conditions can result in severe health consequences and considerable medical care ***,multiple diagnostic modalities are available,which if effectively used together with the administration of appropriate pharmacologic therapies,can minimize any unnecessary patient ***:Although progress has been made in the management of toxocariasis patients,there remains much work to be *** of new technologies and better understanding of the pathogenesis of toxocariasis can identify new diagnostic biomarkers,which may help in increasing diagnostic ***,further clinical research breakthroughs are needed to develop better ways to effectively control and prevent this serious disease.

关键词： Toxocara canis Toxocariasis Zoonosis Larva migrans Epidemiology Diagnosis Control

Modeling of human colonic blood flow for a novel artificial anal sphincter system

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第9期9卷 734-738页

作者： Peng ZAN, guo-zheng YAN, hua liu (School of Electronics, Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China) School of Electronics Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China. zanpeng@***

A novel artificial anal sphincter system has been developed to simulate the normal physiology of the human anorectum. With the goal of engineering a safe and reliable device, the model of human colonic blood flow has been built and the relationship between the colonic blood flow rate and the operating occlusion pressure of the anorectum is achieved. The tissue ischemia is analyzed based on constitutive relations for human anorectum. The results suggest that at the planned operating occlusion pressure of less than 4 kPa the artificial anal sphincter should not risk the vascularity of the human colon.

关键词： Incontinence Artificial anal sphincter Colonic blood flow Tissue ischemia

Diffraction Properties of Blazed Gratings Illuminated with Broad-bandwidth and Divergent Beam

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Semiconductor Photonics and Technology 2008年第1期14卷 13-16页

作者： liu guo-hua liu De-ming Department of Optoelectronics Huazhong University of Science and Technology Wuhan 430074 CHN

Far-field intensity and diffraction efficiency of the blazed reflection gratings illuminated with broad-bandwidth and divergent beam are *** the spectral width and divergence of the incident beam with a constant energy increase,the maximum intensity decreases,and the half width at e-2 of the maximum intensity becomes *** efficiency has no deterioration for the blazed grating with a proper groove shape even when the incident light contains a broad range of wavelengths and comes from a wide range of angles.

关键词： blazed grating broad-bandwidth beam divergent beam fiber lasers