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A simplified three-dimensional extension of Hoek-Brown strength criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 568-578页

作者： hangzhou li Tong Guo Yalin Nan Bo Han Department of Civil Engineering Xi’an Jiaotong UniversityXi’anShaanxi710049China Shaanxi Engineering Research Center of Soil Body China Electronic Research Institute of Engineering Investigation and DesignXi’anShaanxi710054China

The Hoek-Brown(HB)strength criterion has been applied widely in a large number of projects around the ***,this criterion ignores the intermediate principal stress *** evidences have demonstrated that the rock strength is dependent on *** it is necessary to extend the HB criterion into a three-dimensional(3D)*** this study,the effect of s2 on the strength of rocks is identified by reviewing the true triaxial tests of various rock types reported in the literature.A simple 3D strength criterion is *** modified criterion is verified by the true triaxial tests of 13 rock *** results indicate that the modified criterion can achieve a good fit to most of rock *** can represent a series of criteria as b *** comparisons,several existing 3D versions of the HB criterion are selected to predict the strengths of these rock *** is indicated that the proposed criterion works better than other criteria.A substantial relationship between parameter b and the unconfined compressive strength is established,which guarantees that the proposed criterion can still work well even in the absence of true triaxial test data.

关键词： Hoek-Brown(HB)strength criterion Three-dimensional(3D)strength criterion Intermediate principal stress Failure envelope

空气幕对采空区漏风和上隅角瓦斯积聚影响研究

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矿业研究与开发 2024年第10期44卷 167-173页

作者：李杭洲王飞刘红威朱国红刘小平李德军尹宝廷太原理工大学安全与应急管理工程学院山西太原030024 山西煤矿安全研究生教育创新中心山西太原030024 伍伦贡大学土木、采矿与环境工程学院澳大利亚伍伦贡NSW2522 山西工程职业学院山西太原030009 山西阳煤寺家庄煤业有限责任公司山西晋中市030600 山西煤炭进出口集团左云韩家洼煤业有限公司山西大同市037100

为有效防治采空区漏风和上隅角瓦斯积聚,提出在上隅角处布置空气幕系统,通过形成空气幕墙以阻隔采空区回风侧漏风,同时对上隅角处进行加压,达到均压堵漏效果。利用COMSOL数值模拟软件研究空气幕在不同射流宽度、射流速度和射流角度参数... 详细信息

为有效防治采空区漏风和上隅角瓦斯积聚,提出在上隅角处布置空气幕系统,通过形成空气幕墙以阻隔采空区回风侧漏风,同时对上隅角处进行加压,达到均压堵漏效果。利用COMSOL数值模拟软件研究空气幕在不同射流宽度、射流速度和射流角度参数下对采空区漏风、氧化带面积、上隅角瓦斯浓度和采场能位分布的影响。结果表明:随着空气幕射流速度和宽度增大,采空区漏风量和上隅角瓦斯逐渐减少,氧化带面积先减小后增大,大宽度低流速空气幕对横向风流阻挡能力要优于小宽度高流速空气幕;空气幕方向由垂直向水平方向增大射流角度能有效减少采空区漏风和氧化带面积。综合考虑空气幕对采空区漏风、氧化带面积、上隅角瓦斯浓度的影响,空气幕在射流宽度为25 cm、射流角度为20°~30°、射流速度为7~8 m/s时效果最佳;空气幕可以吹散上隅角瓦斯,将瓦斯封闭在采空区内部,有效防治上隅角瓦斯积聚,同时可在采空区内部形成均压效果,有效减少采空区回风侧漏风。

关键词：空气幕采空区漏风防治瓦斯积聚均压堵漏

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注意对冲突责任判断的影响的实验研究

心理科学 2004年第4期27卷 881-883页

作者：李安杭州师范学院心理学系杭州310036

工读学生是介于普通学生与少年犯之间的一个社会群体。已有研究表明 ,工读学生在冲突中比一般人有更多的冲动攻击行为。责任判断是对攻击行为有重要影响的认知过程 ,文章比较了工读学生与普通学生在不同注意条件下 (注意分配与注意集中 ... 详细信息

工读学生是介于普通学生与少年犯之间的一个社会群体。已有研究表明 ,工读学生在冲突中比一般人有更多的冲动攻击行为。责任判断是对攻击行为有重要影响的认知过程 ,文章比较了工读学生与普通学生在不同注意条件下 (注意分配与注意集中 )的责任的判断情况。

关键词：工读学生攻击性行为冲突责任心理健康

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项目反应理论初评

心理科学 1991年第1期14卷 1-5,63页

作者：陈立杭州大学

本文就项目反应理论的几个要点,如单维、局部独立、参数不变、取样无关,和信度与效度等概念,都进行了讨沦。提出了中介变量的理论问题。关于IRT 的方法论与科学推论,以及它和经典测验理论的争论都作了重点的讨论。

关键词：项目反应理论经典测验理论中介变量心理学史信度与效度构思效度因素分析认知心理学内容效度假说

Addition of Organosamarium Reagents toα, β-Unsaturated Esters

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Chinese Chemical Letters 2000年第1期11卷 5-8页

作者： Yun Fa ZHENG Wei liang BAO Yong Min ZHANG( Department of Chemistry, Zhejiang University, Xi Xi Campus, hangzhou 310028 li Shui Teachers College. Zhejiang 323000) li Shui Teachers College Zhejiang 323000 China Department of Chemistry Zhejiang University Xi Xi Campus Hangzhou 310028 China

Allylsamarium bromide reacts with Q, 6 -unsaturated esters and a -alkyloxy carbonyl α, β-unsaturated esters to give l,2-addition and 1 .4-addition products respectively.

关键词： Samarium Grignard reagent conjugate addition α β-unsaturated esters.

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平话心理科学向何处去

心理科学 1997年第5期20卷 385-389页

作者：陈立杭州大学

对心理学现状，要从课题的琐细，及屈从物理方法的独裁解放出来。建议群策群力，从战略的高度，进行战役性的研究，避免仓卒应付的遭遇战。要理论研究结果实际，从现实中发现漏洞以资利用。克服方法论中的诸多限制，比较机器人学的缺陷... 详细信息

对心理学现状，要从课题的琐细，及屈从物理方法的独裁解放出来。建议群策群力，从战略的高度，进行战役性的研究，避免仓卒应付的遭遇战。要理论研究结果实际，从现实中发现漏洞以资利用。克服方法论中的诸多限制，比较机器人学的缺陷，重视意义的地位，采纳释义学的方法，打破“所谓”科学的梏制，以活跃心理学克服科学方法论的专制。

关键词：心理学认知人工智能方法论释义学

Gene heterogeneity of hepatitis B virus isolates from patients with severe hepatitis B

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Hepatobiliary & Pancreatic Diseases International 2005年第4期4卷 530-534页

作者： Wei Wu, Yu Chen, Bing Ruan and Lan-Juan li hangzhou, China Department of Infectious Diseases, First Affiliated Hospital, Zhejiang University School of Medicine, Key Laboratory of Infectious Diseases of Health Ministry of China, hangzhou 310003, China Department of Infectious Diseases First Affiliated Hospital Zhejiang University School of Medicine Key Laboratory of Infectious Diseases of Health Ministry of China Hangzhou 310003 China.

BACKGROUND: The pathogenesis of severe hepatitis B remains unknown. Reports have indicated that hepatitis B virus (HBV) mutations are important factors in the pathogenesis of this disease. This study was to investigate the genetic heterogeneity of HBV strains from serum samples of patients with fulminant hepatitis B. METHODS: Full-length HBV genomes from 4 patients with severe hepatitis B were cloned and sequenced to observe mutations in every open reading-frame ( ORF). Serum samples of another 25 patients with severe hepatitis B, 30 patients with chronic hepatitis B, and 25 HBV carriers were collected for sequencing and comparison of mutations in preS2, preC and core promoter regions. RESULTS: Of 4 HBV full-length genome sequences, 3 had a G to A mutation at nucleotide A1896 in the preC region and 1 had double mutations of T1762-A1764 in the core promoter region. The 4 sequences showed mutations in the known B or T cell epitopes of the preS2 and C regions. For the other 3 groups, more mutations were seen in the preS2 region in the HBV isolates from the patients with severe hepatitis B than those from the patients with chronic hepatitis B and HBV carriers (P <0.01). There was a significant difference of mutations in the T cell epitope region of preS2 between the patients with severe hepatitis B and those with chronic hepatitis B or HBV carriers (P <0.01). In the preC and core promoter regions, the mutation frequencies of T1653 and C1753 were 48.0% and 24.0% respectively in the patients with severe hepatitis B, but none of these mutations were observed in the patients with chronic hepatitis B group or HBV carriers (P <0.01). The mutation frequency of T1762-A1764 was 76.0% in the patients with severe hepatitis B, 40.0% in the patients with chronic hepatitis B (P <0. 01) , and 16. 0% in the HBV carriers ( P < 0. 01). There was a significant difference in A1896 mutation between the patients with severe hepatitis B and the patients with chronic hepatitis B (P < 0. 05 ) o

关键词： hepatitis B virus severe hepatitis virus genome gene heterogeneity preS2 preC core promoter

A CLASS OF SINGULARLY PERTURBED EQUATIONS FOR LARGE PARAMETER WITH THREE TURNING POINTS

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Annals of Differential Equations 2012年第2期28卷 180-185页

作者： Huang li (hangzhou Dianzi University, hangzhou 310018) Xianglin Han , Cheng Ouyang (Huzhou Teachers College, Huzhou 313000, Zhejiang)

A class of singularly perturbed problem of third order equation with two para-meters is studied. Using singular perturbation method, the structure of solutions to the problem is discussed in three different cases about two small parameters. The asymptotic solutions to the problem are given. The structure of solutions and the different limit behaviors are revealed. And the solutions are compared with the exact solutions to the equation in which the coefficients are constants and a relatively more perfect result is obtained.

关键词： singular perturbation turning point outer solution interior layer matching method

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创新与发展的辩证关系研究

理论前沿 2007年第15期504卷 24-25页

作者：李航舟洛阳师范学院后勤服务集团

创新是发展的内在要求,也是发展的根本动力。从一定意义上讲,发展的本质就是创新,创新的结果就是发展。创新是解决发展问题的根本途径。

关键词：创新发展关系