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单向应力作用下地下采空区顶板破坏规律特征

有色金属工程 2024年第1期14卷 130-137页

作者：霍健张泉陶治臣陈晓青辽宁科技大学矿业工程学院辽宁鞍山114051 鞍钢基石矿业有限公司辽宁鞍山114051

针对单向应力作用于地下采空区顶板的破坏规律特性问题,基于弹性薄板理论和压力拱理论,利用单轴压力试验机对顶板模型进行了试验,并探究了不同荷载条件下顶板模型的受压过程和变形特性。结果表明:顶板的破坏过程与峰值应力是否超过疲劳... 详细信息

针对单向应力作用于地下采空区顶板的破坏规律特性问题,基于弹性薄板理论和压力拱理论,利用单轴压力试验机对顶板模型进行了试验,并探究了不同荷载条件下顶板模型的受压过程和变形特性。结果表明:顶板的破坏过程与峰值应力是否超过疲劳强度密切相关,超过疲劳强度时会出现加速破坏阶段;顶板的变形过程可以分为三个阶段,分别对应于不同的应力和应变变化规律;顶板的失稳破坏位置与荷载条件有关,周期荷载条件下更容易导致整体垮落塌陷;侧帮支撑作用对顶板的承载能力和稳定性有正面影响,但也会增加应力集中和变形。研究结果对于理解顶板在不同荷载条件下的力学行为和提高顶板的安全性具有重要意义。

关键词：岩石力学地下空区弹性薄板压力拱应力应变

Evaluation of individualized treatment of nonproliferative diabetic retinopathy:a multicenter,randomized,parallel-controlled study

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Journal of Traditional Chinese Medicine 2022年第1期42卷 90-95页

作者： huo jian DUAN Junguo LIU Lisha ZHANG Fuwen ZHU Keyu SUI Jiaqing jian Wenyuan Department of Ophthalmology Chengdu Women's and Children's Central HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 611731China College of Ophthalmology Chengdu University of Traditional Chinese MedicineChengdu 610075China

OBJECTIVE:To evaluate the differences in the efficacy of stationary treatment and individualized treatment for patients with nonproliferative diabetic retinopathy(NPDR).METHODS:This study was a randomized,controlled,multicenter clinical *** with NPDR were randomized into the stationary treatment group or the individualized treatment *** stationary treatment group was given the basic treatment and Qiming granules,and the individualized treatment group was given the basic treatment,Qiming granules,and individualized Chinese herbal medicines over a 12-week *** individualized therapeutic formula was also changed over time to adjust to the changes in the clinical presentation of the *** conducted observations of fundus retinal exudation and hemorrhage,visual acuity,Traditional Chinese Medicine symptom scores and other ***:A total of 140 participants with NPDR were randomized into the stationary treatment group or the individualized treatment group,and 132 participants completed this *** the 12-week treatment,significant improvements in both primary and secondary outcomes were observed in the stationary and individualized treatment *** remarkable difference in the primary outcomes between the two groups was ***,there was a significant difference in the Traditional Chinese Medicine symptom scores(18±7 vs 15±6;P<0.05).There were no severe adverse ***:Compared with stationary treatment,individualized treatment is more effective at relieving the Traditional Chinese Medicine symptoms and improving vision and fundus lesions at 12 weeks post treatment.

关键词： diabetic retinopathy individualized treatment randomized controlled trial Qiming granules

两机一洞尾水调压室阻抗损失系数模型试验研究

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水电能源科学 2024年第2期42卷 161-165页

作者：周嘉伟胡定辉刘火箭刘志雄长江科学院水力学研究所湖北武汉430014 长江勘测规划设计研究有限责任公司湖北武汉430014

水电站引水发电系统中调压室的阻抗损失系数是影响机组过渡过程计算结果的重要因素,目前阻抗损失系数一般在行业规范推荐的范围内进行取值,往往与试验值有所偏差,不利于调压室体型的优化设计。通过采用大比尺的调压室水工模型,对两机一... 详细信息

水电站引水发电系统中调压室的阻抗损失系数是影响机组过渡过程计算结果的重要因素,目前阻抗损失系数一般在行业规范推荐的范围内进行取值,往往与试验值有所偏差,不利于调压室体型的优化设计。通过采用大比尺的调压室水工模型,对两机一洞型式的水电站阻抗式尾水调压室进行大流量条件下的水力学试验,研究不同水流流态和分流比对调压室阻抗损失系数的影响,分析控制工况下调压室的流入和流出阻抗损失系数,给出了调压室阻抗损失系数与分流比的拟合公式和关系曲线。研究结果填补了两机一洞型式的水电站尾水调压室阻抗损失系数试验的空白,可为此类调压室的水力计算分析提供依据。

关键词：两机一洞尾水调压室模型试验阻抗损失系数分流比

3D打印导板辅助穿刺引流术治疗脑出血临床观察

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中国实用神经疾病杂志 2024年第2期27卷 149-153页

作者：霍健王礼东王旭范家权六安市中医院安徽六安237000

目的探讨3D打印导板辅助穿刺引流术治疗20 mL左右脑出血患者的临床疗效。方法将105例脑出血患者随机分为对照组和观察组,实施常规保守治疗的53例分为对照组,实施3D打印导板辅助穿刺引流术治疗的53例分为观察组。比较2组血肿清除率、神... 详细信息

目的探讨3D打印导板辅助穿刺引流术治疗20 mL左右脑出血患者的临床疗效。方法将105例脑出血患者随机分为对照组和观察组,实施常规保守治疗的53例分为对照组,实施3D打印导板辅助穿刺引流术治疗的53例分为观察组。比较2组血肿清除率、神经功能[美国国立卫生研究院卒中量表(NIHSS)评分]、认知功能[简易智力状态检查量表(MMSE)评分]及肢体功能[Fugl-Meyer运动功能量表(FMA)评分],并记录2组治疗期间并发症情况。结果观察组治疗后1 d、3 d及10 d的血肿清除率分别为(78.45±5.06)%、(80.73±5.29)%及(82.68±5.17)%,高于对照组的(32.16±4.12)%、(36.47±4.38)%、(42.67±4.78)%(P<0.05),观察组住院时间短于对照组(P<0.05)。治疗后,观察组NIHSS评分为(13.17±1.82)分,显著低于对照组的(18.64±2.71)分(P<0.05),MMSE评分和FMA总评分显著高于对照组[(28.67±1.24)分比(26.25±2.62)分,(77.03±10.13)分比(65.50±8.89)分](P<0.05)。观察组总并发症发生率为5.76%,低于对照组的18.87%(P<0.05)。结论相对于保守治疗,3D打印导板辅助穿刺引流术治疗20 mL左右脑出血患者疗效确切,可显著提升患者血脂清除率,改善患者认知功能和肢体功能,且能降低脑出血总并发症发生率。

关键词：脑出血 3D打印导板穿刺引流术认知功能肢体功能并发症

Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–H bond: quick access to multi-substituted aryl olefins

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Science China Chemistry 2024年第3期67卷 882-889页

作者： jian Yao Lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct C–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–H functionalization

Spontaneous remission of autoimmune pancreatitis: Four case reports

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World Journal of Clinical Cases 2022年第23期10卷 8232-8241页

作者： Bin-Bin Zhang jian-Wei huo Zheng-Han Yang Zhen-Chang Wang Er-Hu Jin Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Radiology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing 100010China

BACKGROUND Autoimmune pancreatitis(AIP)is a particular type of chronic pancreatitis,and steroid treatment of AIP is *** remission(SR)of AIP without steroids is relatively *** international consensus for the treatment of autoimmune pancreatitis suggests that patients with AIP with obstructive jaundice,abdominal pain,and back pain related to the pancreas or the bile duct should be treated with steroids;most asymptomatic patients with AIP may improve without ***,in our clinical work,we found that the clinical characteristics of AIP patients with SR *** of these cases are described *** addition,to our knowledge,there is no previously published report of dynamic imaging before and after SR of AIP at *** SUMMARY We present the cases of four patients with AIP(two females and two males)in which the AIP improved spontaneously without steroid *** patients were asymptomatic,one patient had abdominal pain with obstructive jaundice,and one patient had intermittent right upper abdominal *** patients presented with localized pancreatic enlargement and one with diffuse pancreatic *** addition to the pancreatic lesions,bile duct involvement was seen in two patients,and no extra-pancreatic organ involvement was found in the other two *** serum IgG4 level of all patients was more than twice the normal *** SR in the four patients,the affected pancreases exhibited three types of image features:Return to normal,progressive fibrosis,and atrophy and *** The clinical features of SR in our four patients with AIP differ,but the imaging findings share some *** SR,in some cases the affected pancreas could return to normal,although some patients suffer from progressive fibrosis and atrophy as well as calcification.

关键词： Autoimmune pancreatitis Spontaneous remission Computed tomography Magnetic resonance imaging Case report

Rainfall amount determines annual herb controls over soil seed bank and its similarity with vegetation in the Tengger Desert

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Ecological Processes 2022年第1期11卷 27-37页

作者： Ya‑Fei Shi Zeng‑Ru Wang Bing‑Xin Xu jian‑Qiang huo Rui Hu Yang Zhao Zhi‑Shan Zhang Shapotou Desert Research and Experiment Station Northwest Institute of Eco‑Environment and ResourcesChinese Academy of SciencesLan‑zhou 730000Gansu ProvincePeople’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China State Key Laboratory of Grassland Agro‑Ecosystems Key Laboratory of Grass‑land Livestock Industry InnovationMinistry of Agriculture and Rural AffairsEngineering Research Center of Grassland IndustryMinistry of EducationCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020Gansu ProvincePeople’s Republic of China

Background:Soil seed banks may offer great potential for maintaining and restoring desert ecosystems that have been degraded by climate change and anthropogenic ***,few studies have explored the year‑to‑year dynamics in the species composition(richness and abundance)of these desert soil seed ***,we conducted a 4‑year study to assess the effects of environmental factors(meteorology and microtopography)and aboveground vegetation on the soil seed bank of the Tengger Desert,***:We found the seed bank was dominated by annual herb species both in species richness and *** rainfall in the growing season increased the number of seeds in the soil seed bank,and quadrat micro‑elevation had a negative effect on soil seed bank *** species composition in the seed bank had significantly larger between‑year similarity than that in the aboveground vegetation due to the dominance of annual herb *** different life forms,the species composition of annual herbs showed distinctly larger temporal similarity between the aboveground vegetation and the seed bank compared with perennial herbs and ***:Our findings highlight that the combined effects of environmental factors and plant life forms deter‑mine the species composition(especially the abundance)of soil seed banks in ***,if degraded desert ecosystems are left to regenerate naturally,the lack of shrub and perennial herb seeds could crucially limit their *** intervention and management may have to be applied to enhance the seed abundance of perennial lifeforms in degraded deserts.

关键词： Desert ecosystem Seed bank dynamics Rainfall Plant type Vegetation regeneration Annual herbs

Synergistic asymmetric diarylation of tethered alkenes via C–H functionalization of simple(hetero)arenes

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Science China Chemistry 2024年第8期67卷 2710-2718页

作者： jian Yao Can Zhao Lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–H functionalization bifunctional role chiral oxindoles

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Numerical Study on the Effect of Gap Diffraction on the Hydrodynamic Performance of A Floating Breakwater

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China Ocean Engineering 2024年第4期38卷 663-675页

作者： BIAN Xiang-qian JI Chun-yan XU Sheng GUO jian-ting huo Fa-li School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring *** a reasonable gap between the flume wall and the FBs is a critical step in 2D flume ***,research on the effect of the gap on the accuracy of 2D FB experimental results is *** address this issue,a numerical wave tank is developed using CFD to estimate the wave-FB interaction of a moored dual-cylindrical FB,and the results are compared to experimental data from a previously published *** is good agreement between them,indicating that the numerical model is sufficiently *** numerical model is then applied to explore the effect of gap diffraction on the performance of FBs in2D *** was discovered that the nondimensional gap length L_(Gap)/W_(Pool)should be smaller than 7.5%to ensure that the relative error of the transmission coefficient is smaller than 3%.The influence of the gap is also related to the entering wave properties,such as the wave height and period.

关键词： floating breakwater diffraction effect gap hydrodynamic performance model experiments CFD numerical simulation