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Underground Space 2024年第5期18卷 130-150页

作者： Shimin Wang xuhu He Xiaoyu Peng Ya Wang Zhengxin Li Zihan Song Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

In large-diameter shield tunnels,applying the double-layer lining structure can improve the load-bearing properties and maintain the stability of segmental *** secondary lining thickness is a key parameter in the design of a double lining structure,which is worth being *** on an actual large-diameter shield tunnel,loading model tests are carried out to investigate the effect of the secondary lining thickness on the mechanical behaviours of the double lining *** test results show that within the range of secondary lining thicknesses discussed,the load-bearing limit of the double-layer lining increases with growing secondary lining *** a passive support,the secondary lining acts as an auxiliary load-bearing structure by contacting the *** changes in secondary lining thickness have a significant effect on the contact state between the segment and secondary lining,with both the contact pressure level and the contact area between the two *** double-layer lining structures in large-diameter shield tunnels,it is proposed that the stiffness of the secondary lining needs to be matched to the stiffness of the segment,as this allows them to have a coordinated deformation and a good joint load-bearing effect.

关键词： Large-diameter shield tunnels Double-layer lining structure Secondary lining thickness Stiffness matching Similar model test

Deformation control criterion of shield tunnel under lateral relaxation of soft soil

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 780-795页

作者： Shimin WANG Xiaoyu PENG Hang ZHOU xuhu HE Anqi ZHOU Bing CHEN Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610036China Guangdong Provincial Railway Construction Investment Group Co. LtdGuangzhou 510080China

Metro shield tunnels under the lateral relaxation of soil(LRS)are susceptible to significant lateral deformations,which jeopardizes the structural safety and ***,deformation control standards for such situations have not been clearly ***,based on a specific case,a model test is conducted to realize the LRS of a shield tunnel in a sandy stratum to reveal its effect on segment ***,a deformation control criterion is *** LRS is simulated by linearly reducing the loads applied to the lateral sides of the segment *** lateral unloading,the lateral earth pressure coefficient on the segment decreases almost exponentially,and the structural deformation is characterized by horizontal expansion at the arch haunches and vertical shrinkage at the arch vault and arch *** on the mechanical pattern of the segment structure and the acoustic emission,the deformation response of a segment can be classified into three stages:elastic and quasi-elastic,damage,and rapid deformation *** a shield tunnel with a diameter of approximately 6 m and under the lateral relaxation of sandy soil,when the ellipticity of the segment is less than 2.71%,reinforcement measures are not ***,the segment deformation must be controlled when the ellipticity is 2.71%to 3.12%;in this regard,an ellipticity of 3%can be used as a benchmark in similar engineering projects.

关键词： shield tunnel lateral relaxation of soil deformation control criterion of segment structure model test

Influence of Nuclear Deformation on the Potential Energy Surface in Di—Nuclear Model

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Chinese Physics Letters 2003年第5期20卷 635-638页

作者： WANGNan ZHAOEn-Guang LIJian-Feng LIWen-Fei xuhu-Shan ZUOWei LIJun-Qing InstituteofTheoreticalPhysics ChineseAcademyofSciencesBeijing100080 InstituteofModermPhysics ChineseAcademyofSciencesLanzhou730000

Influence of the nuclear deformation on the potential energy surface (PES) in a di-nuclear system is studied in details. It is found that the PES shape changes greatly due to the deformation effect. The top point of the PES could be reduced significantly, which implies that the optimum excitation energy could also be reduced greatly and may enhance the formation probability of the compound nucleus. The dynamical deformation as a function of the reaction time in the reaction process is dramatic. The Z/N ratios of fragments tend to follow that of the compound nucleus during the nucleon exchange process, but to fluctuate.

关键词：原子核物理学变形 PES 核反应二次核模型能量

Study of Survival Probability of Super Heavy Nuclei

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Communications in Theoretical Physics 2003年第2X期40卷 199-202页

作者： WANGNan ZHAOEn-Guang LIWen-Fei LIJian-Feng xuhu-Shan ZUOWei LIJun-Qing InstituteofTheoreticalPhysics theChineseAcademyofSciencesBeijing100080China InstituteofModernPhysics theChineseAcademyofSciencesLanzhou730000China CenterofTheoreticalNuclearPhysics NationalLaboratoryofHeavyIonAcceleratorLanzhou730000China

The survival probability of super heavy nuclei produced in cold fusion reactions is studied by using the standard Fermi gas level density formula and analyzed with fission and neutron evaporation characteristics predicted in different theoretical models. The level density formula used in this letter suppresses the ratio of neutron emission width to fission width, Гn/Гf. The dependence of Гn/Гf on the saddle point level density parameter and excitation energy is also investigated.

关键词：超重原子核超重元素幸存可能性裂变宽度中子发射宽度

Specific detection and effective inhibition of a single bacterial species in situ using peptide mineralized Au cluster probes

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Science China Chemistry 2018年第5期61卷 627-634页

作者： Xiangchun Zhang Li Liu Ru Liu Jing Wang xuhu Hu Qing Yuan Juanjuan Guo Gengmei Xing Yuliang Zhao Xueyun Gao CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Chemistry and Chemical Engineering Beijing University of Technology Beijing 100124 China University of Chinese Academy of Sciences Beijing 100049 China

Increasingly serious microbial infections call for the development of new simpler methods for the precise diagnosis and specific inhibition of such pathogens. In this work, a peptide mineralized Au cluster probe was applied as a new simplified strategy to both recognize and inhibit a single bacteria species of Staphylococcus aureus(S. aureus) simultaneously. The probes are composed of peptides and Au clusters. Moreover, the peptides specifically target S. aureus cells and the Au clusters provide fluorescent imaging and have an antibacterial effect. These new probes enable the simultaneous specific detection and effective destruction S. aureus cells in situ.

关键词： Au cluster probes single bacteria species S aureus specific detection effective inhibition

Methylenetetrahydrofolate Reductase Genotypes, Dietary Habits and Susceptibility to Stomach Cancer

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Chinese Journal of Clinical Oncology 2004年第3期1卷 162-166页

作者： ChangmingGao TakezakiToshiro JianzhongWu JianhuoDing YantingLiu SupingLi PingSu xuhu TianliongXu HamajimaNobuyuki TajimaKazuo DivisionofEpidemiology JiangsuProvinceInstituteofCancerResearchNanjing210009China. DivisionofEpidemiologyandPrevention AichiCancerCenterResearchInstituteNagoya464-8681Japan. PublicHealthCenterofChuzhouDistrict Huaian221300China.

OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach cancer (SC).METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian, Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects..MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and SC cases (79.4%,P=0.0416), the increased risk had an adjusted OR of 1.79 (95%C1:1.01-3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intakeof meat, the carriers of the MTHFR C/T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their exposure level to environmental factors.

关键词：亚甲基四氢叶酸还原酶基因型饮食习惯易感性胃癌肿瘤

Effect of chemical treatments on seed germination and early seedling growth of Kobresia

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Effect of chemical treatments on seed germination and early ...

Precise mode control of laser-written waveguides for broadband,low-dispersion 3D integrated optics

第十八届中国科协年会——分14 西北地区农牧结合发展草牧业研讨会

作者： xuhu ZHANG Xitong CHU Yuefei XU Department of Grassland Science College of Animal Science and Technology Northwest A&F University

Seeds of Kobresia, which grow on Qinghai-Tibet plateau, China, are known for poor performance in germination and early seedling development. In this study, we investigated the effect of chemicals on seed germination and early seedling growth in five species of Kobresia seeds(Kobresia setchwanensis, Kobresia royleana, Kobresia littledalei, Kobresia capillifolia and Kobresia pygmaea). To assess the actual germination level, we performed germination experiments comparing the behaviors of seeds without any treatment, and tests showed the inherent differences among various species. Pretreatments of these seeds with sodium hydroxide(Na OH), potassium nitrate(KNO3) and sulfuric acid(H2SO4) also been tested and turned out that the best method to enhance germination performance for K. setchwanensis, K. littledalei and K. pygmaea was to immerse seeds in 40% Na OH solution. All the five species of Kobresia had longer shoot lengths with treatments of higher Na OH solution concentration. Moreover, KNO3 and H2SO4 do have influence on Kobresia seed germination and seedling growth in some specific species. These results suggested that all the chemicals involved had impacts on germination performance, further promoted the early seedling growth of almost all the selected seeds.

关键词： Kobresia Qinghai-Tibet Plateau germination seedling growth

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Light(Science & Applications) 2024年第6期13卷 1186-1195页

作者： Yuying Wang Lijing Zhong Kuen Yao Lau xuhu Han Yi Yang Jiacheng Hu Sergei Firstov Zhi Chen Zhijun Ma Limin Tong Kin Seng Chiang Dezhi Tan Jianrong Qiu College of Optical Science and Engineering Zhejiang University310027HangzhouChina Institute of Light+X Science and Technology College of Information Science and EngineeringNingbo University315211NingboChina School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University215006SuzhouChina Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center38 Vavilov str.Moscow119333Russia Zhejiang Lab 311121HangzhouChina College of Materials Science and Engineering Key Laboratory of Advanced Materials of Yunnan ProvinceKunming University of Science and Technology650093KunmingYunnanChina Department of Electrical Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong SARChina School of Materials Science and Engineering Zhejiang University310027HangzhouChina

Three-dimensional(3D)glass chips are promising waveguide platforms for building hybrid 3D photonic circuits due to their 3D topological capabilities,large transparent windows,and low coupling *** present,the key challenge in scaling down a benchtop optical system to a glass chip is the lack of precise methods for controlling the mode field and optical coupling of 3D waveguide ***,we propose an overlap-controlled multi-scan(OCMS)method based on laser-direct lithography that allows customizing the refractive index profile of 3D waveguides with high spatial precision in a variety of *** the basis of this method,we achieve variable mode-field distribution,robust and broadband coupling,and thereby demonstrate dispersionless LP21-mode conversion of supercontinuum pulses with the largest deviation of<0.1 dB in coupling ratios on 210 nm *** approach provides a route to achieve ultra-broadband and low-dispersion coupling in 3D photonic circuits,with overwhelming advantages over conventional planar waveguide-optic platforms for on-chip transmission and manipulation of ultrashort laser pulses and broadband supercontinuum.

关键词： waveguide mode dispersion

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岩石材料力学相似性定量评价方法研究

中国石油大学学报（自然科学版） 2015年第5期39卷 137-143页

作者：任旭虎张卓单亦先中国石油大学信息与控制工程学院山东青岛266580 中海油山东化学工程有限责任公司山东济南250101

材料的相似度是物理模拟实验的关键因素,分析两种定量化评价方法。提出一种基于应力-应变曲线的岩石材料力学相似性定量评价法,由应力-应变曲线评价、基于应力-应变曲线的π值评价和综合评价3部分组成。通过综合评价指标描述相似程度。... 详细信息

材料的相似度是物理模拟实验的关键因素,分析两种定量化评价方法。提出一种基于应力-应变曲线的岩石材料力学相似性定量评价法,由应力-应变曲线评价、基于应力-应变曲线的π值评价和综合评价3部分组成。通过综合评价指标描述相似程度。结果表明:评价内容应包含材料参数两个方面的特性,即相似材料参数理论值与实际值的近似度和相似材料参数满足无量纲数的情况。验证了所提出的方法在构造变形与烃类充注一体化物理模拟中的准确性和实用性。

关键词：相似性评价相似材料岩石力学应力-应变曲线

E-cadherin gene C-160A promoter polymorphism and risk of non-cardia gastric cancer in a Chinese population

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World Journal of Gastroenterology 2005年第1期11卷 56-60页

作者： YanLu Yao-Chuxu JingShen Rong-BinYu Ju-YinNiu Jian-TaoGuo xuhu Hong-BingShen DepartmentofEpidemiologyandBiostatistics NanjingMedicalUniversitySchoolofPublicHealthNanjing210029JiangsuProvinceChina JintanCenterforDiseaseControlandPrevention JintanCity213200JiangsuProvinceChina HuaianCenterforDiseaseControlandPrevention Huaian223200JiangsuProvinceChina

AIM: To test the hypothesis that E-cadherin gene (CDH1)C-160A promoter variant genotype is associated with an increased risk for developing gastric ***: In this population-based case-control study of gastric cancer in Jiangsu Province, China, we performed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to genotype the C-160A polymorphism of CDH1 promoter in 206 non-cardia gastriccancer patients and 261 age- and sex-matched but unrelated cancer-free ***: The frequencies of genotypes CC, CA and AA were 57.8%, 36.4% and 5.8% in gasfric cancer cases,respectively, and 58.2%, 34.9% and 6.9% in controls respectively. The distributions of CDH1 genotypes were not significantly different between gastric cancer cases and controls (P = 0.87 for genotype frequency and P = 0.92for allele frequency). Compared with the CC genotype, the CA and AA genotypes were not associated with an increased risk for non-cardia gastric cancer (adjusted odds ratios (OR)= 1.15, and 95% confidence interval (95% CI) = 0.78-1.72for CA genotype, and OR = 0.90 and 95% CI = 0.42-2.01for AA genotype).CONCLUSION: E-cadherin gene C-160A promoter polymorphism may not play a major role in the etiology of non-cardia gastric cancer in Chinese population.

关键词： Gastric cancer E-cadherin gene Promoter Polymorphism