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Research and application of mechanical models for the whole process of 110 mining method roof structural movement

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Journal of Central South University 2022年第9期29卷 3106-3124页

作者： BIAN Wen-hui YANG Jun HE Man-chao ZHU Chun xu dong-ming School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Geomechanics and Deep Underground Engineering Beijing 100083China School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China

For the 110 mining method,it is challenging to accurately calculate the support resistance of the roadway due to the lack of understanding of the dynamic movement of the overlying strata in this *** consequential excessive support results in a significant increase in the cost of roadway *** authors explored the overlying strata movement and roadway deformation of the gob-entry retaining in the 110 mining method to solve this ***,the typical stages of the roof-cutting gob-side entry were ***,the mechanical model and calculation formula of the support resistance on the roof were ***,using numerical simulation software,the starting ranges of the specific supports at different stages were verified and the feasibility of the support scheme was ***,combined with the field measurement data,the stress and the deformation of the gob roadway at different stages under the influence of two mining processes in the 110 mining method were *** numerical simulation results obtained are consistent with the field test results,providing a theoretical basis for precision support at different stages by the 110 mining method.

关键词： 110 mining method gob-side entry retaining roof structure movement mechanical model

Application of excavation compensation method for enhancing stability and efficiency in shallow large-span rock tunnels

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Journal of Central South University 2024年第9期31卷 3242-3263页

作者： BIAN Wen-hui YANG Jun ZHU Chun WANG Ke-xue xu dong-ming School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Tunnel Engineering Beijing 100083China School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China

Engineering shallow,large-span rock tunnels challenges deformation control and escalates construction *** study investigates the excavation compensation method(ECM)and its associated technologies to address these *** five key technologies,the ECM effectively modulates radial stress post-excavation,redistributes stress in the surrounding rock,and eliminates tensile stress at the excavation ***-tensioning measures further enhance the rock’s residual strength,establishing a new stability *** tests corroborate the method’s effectiveness,demonstrating a crown settlement reduction of 3–8 mm,a nearly 50%decrease compared to conventional construction ***,material consumption and construction duration were reduced by approximately 30%–35%and 1.75 months per 100 m,***,the ECM represents a significant innovation in enhancing the stability and construction efficiency of large-span rock tunnels,marking a novel contribution to the engineering field.

关键词： excavation compensation method rocky tunnels shallow spanning tunnels tunnel support field test

高应变率下延性金属中微孔洞贯通行为的数值分析

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兵工学报 2012年第9期33卷 1095-1100页

作者：王永刚徐东明宁波大学力学与材料科学研究中心浙江宁波315211

采用有限元分析方法,研究了延性金属材料动态拉伸断裂过程中微孔洞之间贯通行为,讨论了初始孔洞间韧带距离和加载应变速率的影响。通过实时跟踪测量微孔洞长大过程中的形状改变,定量判断微孔洞开始贯通时刻。计算结果显示微孔洞从独立... 详细信息

采用有限元分析方法,研究了延性金属材料动态拉伸断裂过程中微孔洞之间贯通行为,讨论了初始孔洞间韧带距离和加载应变速率的影响。通过实时跟踪测量微孔洞长大过程中的形状改变,定量判断微孔洞开始贯通时刻。计算结果显示微孔洞从独立长大向微孔洞贯通转变开始的临界韧带距离约为0.5倍微孔洞实时直径,其对初始微孔洞间韧带距离和加载应变速率不敏感。从物理机制上看,微孔洞间贯通行为是通过塑性应变场相互作用实现的,但孔洞间韧带区域的塑性应变场需要达到一个临界阈值才能驱动微孔洞开始贯通。在材料中微孔洞统计均匀分布的假定条件下,指出临界孔洞间韧带距离(ILDc)判据和临界孔洞体积分数(fc)判据在物理本质是一致的,可以相互转换。

关键词：固体力学高应变率微孔洞贯通延性金属数值模拟

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全球外汇储备激增及管理策略的国际比较

国际贸易问题 2007年第5期293卷 113-116页

作者：徐明东复旦大学金融研究院

自1995年以来,全球尤其是新兴经济国家外汇储备表现出了史无前例的特征:规模急剧增加、国家集中度提高、地区分布特征明显等。外汇储备激增和外汇储备的过量会给国内宏观经济带来一系列的风险和成本,增加了官方外汇储备资产管理的难度... 详细信息

自1995年以来,全球尤其是新兴经济国家外汇储备表现出了史无前例的特征:规模急剧增加、国家集中度提高、地区分布特征明显等。外汇储备激增和外汇储备的过量会给国内宏观经济带来一系列的风险和成本,增加了官方外汇储备资产管理的难度。本文对外汇储备激增国际背景下全球主要储备国或地区外汇储备管理的经验做了比较分析,并对我国的外汇储备管理提出了建议。

关键词：外汇储备冲销政策储备管理策略

Chemical constituents from the stems of Gymnema sylvestre

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Chinese Journal of Natural Medicines 2014年第4期12卷 300-304页

作者： LIU Yue xu Tun-Hai ZHANG Man-Qi LI xue xu Ya-Juan JIANG Hong-Yu LIU Tong-Hua xu dong-ming Jilin Academy of Chinese Medicine Sciences Department of Traditional Chinese Medicine Chemistry School of Traditional Chinese Medicine Beijing University of Chinese Medicine School of Pharmacy China Pharmaceutical University School of Pharmacy Jilin University Department of General Internal Medicine The First Hospital of Jilin University Jilin University

AIM: To study the chemical constituents of stems of Gymnema sylvestre(Retz.) Schult. METHODS: Chromatographic techniques using silica gel, C18 reversed phase silica gel, and prep-HPLC were used. The structures were elucidated on the basis of MS and spectroscopic analysis(1D and 2D NMR), as well as chemical methods. RESULTS: Seven compounds were isolated and their structures were elucidated as conduritol A(1), stigmasterol(2), lupeol(3), stigmasterol-3-O-β-D-glucoside(4), the sodium salt of 22α-hydroxy-longispinogenin-3-O-β-D-glucopyranosyl-(1→3)-β-D-glucurono-pyranosyl-28-O-α-L-rhamnopyranoside(5), oleanolic acid-3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside(6), and the sodium salt of 22α-hydroxy-longispinogenin 3-O-β-D-glucuronopyranosyl-28-O-α-L-rhamnopyranoside(7). The inhibition activities of compounds 1, 5-7 on non-enzymatic glycation of protein in vitro were evaluated. CONCLUSION: Compound 7 is a new triterpenoid saponin. It was shown that compounds 1, 5-7 have weak inhibition activities for non-enzymatic glycation of protein in vitro.

关键词： Gymnema sylvestre Triterpenoid saponin Non-enzymatic glycation-inhibiting activity

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高硬度球面磨削中球面形状误差分析与补偿

上海交通大学学报 2011年第11期45卷 1690-1694页

作者：李冬冬许明明侯海云胡德金许黎明上海交通大学机械与动力工程学院上海200030

为了提高高硬度球面磨削后的形状精度,分析了新型高硬度球面磨削机床中球面形状误差来源,针对实际加工过程中出现的鞍形球面,提出了采用退让式球面磨削的方法.实验结果表明:退让式球面磨削可以有效减小球面形状误差,对高硬度球面磨削具... 详细信息

为了提高高硬度球面磨削后的形状精度,分析了新型高硬度球面磨削机床中球面形状误差来源,针对实际加工过程中出现的鞍形球面,提出了采用退让式球面磨削的方法.实验结果表明:退让式球面磨削可以有效减小球面形状误差,对高硬度球面磨削具有实用价值.

关键词：高硬度球面磨削球面形状误差误差补偿

消费者网络口碑推荐意愿提升策略研究——基于心理调节定向视角

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情报科学 2016年第6期34卷 151-154页

作者：董颖许正良徐东溟吉林大学管理学院吉林长春130022 东北师范大学人文学院吉林长春130117 昆士兰大学商学院

互联网商业时代,网络口碑推荐已成为影响消费者决策的关键要素,这要求企业对其主动管理和应用以促进产品和服务的销售。但企业在实际操作时往往是经验式地随意进行,并没有抓住影响消费者网络口碑推荐意愿的核心问题,导致效果不佳或资源... 详细信息

互联网商业时代,网络口碑推荐已成为影响消费者决策的关键要素,这要求企业对其主动管理和应用以促进产品和服务的销售。但企业在实际操作时往往是经验式地随意进行,并没有抓住影响消费者网络口碑推荐意愿的核心问题,导致效果不佳或资源浪费。本文从消费者心理调节定向视角入手,运用调节定向匹配理论深入分析消费者网络口碑推荐的内在机制,指出企业应该精准定位消费者,制定与消费者调节定向相匹配的策略,以提升消费者网络口碑推荐意愿。

关键词：调节定向网络口碑推荐意愿提升策略

Effects of two novel nucleoside analogues on different hepatitis B virus promoters

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World Journal of Gastroenterology 2008年第12期14卷 1836-1841页

作者： Xing-Xing He Ju-Sheng Lin Ying Chang Ying-Hui Zhang Yan Li Xiao-Yan Wang dong xu Xiao-ming Cheng Instituteof liver diseases Tongji Hospital of Tongji Medical Co11~g~Huazhong University of Science and Technology Wuhan 430030Hubei Province China

AIM： To explore the effects of the nucleoside analogues β-L-D4A and β-LPA on hepatitis B virus （HBV） promoters. METHODS： Four HBV promoters were amplified by polymerase chain reaction （PCR） and subcloned into the expression vector pEGFP-1. The four recombinants controlled by HBV promoters were confirmed by restriction analysis and sequencing. Human hepatoma HepG2 cells transfected with the recombinant plasmids were treated with various concentrations of β-L-D4A and β-LPA. Then, enhanced green fluorescent protein （EGFP）-positive cells were detected by fluorescence microscopy and using a fluorescence activated cell sorter RESULTS： Four HBV promoters were separately obtained and successfully cloned into pEGFP-1, Expression of EGFP under the control of the surface promoter （Sp） and the X promoter （Xp） was inhibited by β-L-D4A in a dosedependent manner, while expression of EGFP under the control of the core promoter （Cp） and Xp was inhibited by β-LPA in a dose-dependent manner. CONCLUSION： The two novel nucleoside analogues investigated here can inhibit the activities of HBV promoters in a dose-dependent manner. These findings may explain the mechanisms of action by which these two novel compounds inhibit HBV DNA replication.

关键词： Hepatitis B virus Nucleoside analogue Hepatitis B virus promoter Enhanced green fluorescentprotein Fluorescence activated cell sorter

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川麦冬中的新呋甾皂苷的分离与鉴定

高等学校化学学报 2007年第2期28卷 286-288页

作者：徐暾海陈萍徐雅娟郝羚竹解生旭徐东铭北京中医药大学中药学院北京100102 吉林省中医中药研究院长春130021

Traditional Chinese Medicine "maidong"[Ophiopogon japonicus(Thunb.) Ker-Gawl] is the important medicine used to treat cardiovascular diseases.A new furosteroidal saponin,together with three known steroidal saponins,was isolated from the tuber of Ophiopogon japonicus(Thunb.) *** structure of the new furosteroidal saponin,named Ophiopogoside A,was elucidated as 26-O-β-D-glucopyranosyl-(25S)-1β,3β,22α,26-tetrahydroxyfurot-5-ene 3-O-[-α-L-arabinopyranosyl(1→3)]-α-L-rhamnopyranosyl(1→2)-β-D-fucopyranoside mainly by using 1D,2D NMR techniques,ESI-MS analysis as well as chemical methods.

关键词：川麦冬甾体皂苷麦冬呋甾皂苷A