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Mechanism of anomalous low friction phenomenon in deep block rock mass

Mining Science and Technology 2009年第4期19卷 409-419页

作者： WU Hao FANg Qin ZHANg ya-dong LU Yu-sheng LIU Jin-chun Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing Jiangsu 210007 China

Deep rock mass has the unique ＂self-stressed＂ block-hierarchical structure, anomalous low friction （ALF） was one of the typical nonlinear get-mechanical and dynamic responses in deep block rock mass, which occurred as the result of movements of large-scale get-blocks under the impact of external pulses （such as a deep confined explosion, earthquakes, rock bursts and etc.）. ALF phenomenon obtained its name to describe the curious phenomenon that the friction between interacting get-blocks qua- si-periodically disappears at some discrete points in time along the direction orthogonal to the direction of the external pulse. With the objective to confirm the existence of the ALF phenomenon and study the get-mechanical conditions for its occurrence experi- mentally and theoretically, laboratory tests on granite and cement mortar block models were carried out on a multipurpose testing system developed independently. The ALF phenomenon was realized under two loading schemes, i.e., blocks model and a working block were acted upon jointly by the action of a vertical impact and a horizontal static force, as well as the joint action of both ver- tical and horizontal impacts with differently delayed time intervals. We obtained the rules on variation of horizontal displacements of working blocks when the ALF phenomenon was realized in two tests. The discrete time delay intervals, corresponding to local maxima and minima of the horizontal displacement amplitudes and residual horizontal displacements of the working block, satis- fied canonical sequences multiplied by （√2）＇. Some of these time intervals satisfied the quantitative expression （√2）＇ ,alva. At last, 1D dynamic theoretical model was established, the analytical results agreed better with the test data, while the quantitative expression drawn from test data was not validated well in theoretical analyses.

关键词： deep block rock mass block-hierarchical structure optical fiber displacement meter anomalous low friction canonical sequence

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耐热镁合金的开发与研究现状

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轻合金加工技术 2009年第5期37卷 1-6页

作者：石雅静李全安任文亮张兴渊河南科技大学材料科学与工程学院河南洛阳471003

分析了镁合金的高温蠕变机制及耐热镁合金的设计思路,综述了通过添加稀土元素(RE)、碱土元素(Ca、Sr)及其他元素(Si、Bi、Sn)开发耐热镁合金的现状,指出研究与开发价格低廉、工艺性能良好、综合力学性能良好的耐热镁合金是今后耐热镁合... 详细信息

分析了镁合金的高温蠕变机制及耐热镁合金的设计思路,综述了通过添加稀土元素(RE)、碱土元素(Ca、Sr)及其他元素(Si、Bi、Sn)开发耐热镁合金的现状,指出研究与开发价格低廉、工艺性能良好、综合力学性能良好的耐热镁合金是今后耐热镁合金的发展方向。

关键词：镁合金耐热性抗蠕变性能力学性能

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A facile method to fabricate high-quality perovskite nanocrystals based on single crystal powder

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Nano Research 2019年第10期12卷 2640-2645页

作者： Jin-Feng Liao Yi-Xin Chen Jun-Hua Wei ya-Ting Cai Xu-Dong Wang ya.g-Fan Xu Dai-Bin Kuang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China

Although great advancements have been successfully achieved in ligand-assisted reprecipitation strategy(LARP)towards lead halide perovskite nano crystals(NCs)syn thesis,it still remains challe nging to develop bright and stable iodide-based perovskite NC via facile ***,striki ngly bright MAPbl3 NCs with photoluminesce nee qua ntum yield(PLQY)as high as 79%are synthesized via replacing the raw material(MAI and Pbh)with MAPbl3 crystal powder during LARP *** has been found that crystal powder derived MAPbl3 NCs are more iodide-rich compared with that based on raw material,which is favorable to passivate the surface trap ***,femtosecond transient absorption spectroscopies and space charge limited current measurements have corroborated that the trap density is much less in crystal powder resulted MAPbl3 *** analyses indicate stronger solvation with reduced precursor colloid size has been observed in crystal powder derived precursor solution probably due to the formation of *** work has provided a facile but valid method to enhance the photoluminesce nee of perovskite NC via modulati ng the beginning precursor solution.

关键词： MAPbh nanocrystal perovskite transient absorption light emitting

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ICE1 interacts with IDD14 to transcriptionally activate QQS to increase pollen germination and viability

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Journal of Integrative Plant Biology 2024年第8期66卷 1801-1819页

作者： Landi Luo yan Zheng Xieshengya.g Li Qian Chen Danni ya.g Zhijia gu ya ya.g Yunqiang ya.g Xiangxiang Kong Yongping ya.g CAS Key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical GardenThe Chinese Academy of SciencesXishuangbanna 666303China germplasm Bank of Wild Species Yunnan Key Laboratory for Crop Wild Relatives OmicsKunming Institute of BotanyThe Chinese Academy of SciencesKunming 650201China School of Agriculture Yunnan UniversityKunming 650091China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyThe Chinese Academy of SciencesKunming 650201China

In flowering plants,sexual reproductive success depends on the production of viable pollen ***,the mechanisms by which qua QUINE STARCH(QQS)regulates pollen development and how transcriptional activators facilitate the transcription of QQS in this process remain poorly ***,we demonstrate that INDUCER OF CBF EXPRESSION 1(ICE1),a basic helix–loop–helix(b HLH)transcription factor,acts as a key transcriptional activator and positively regulates QQS expression to increase pollen germination and viability in Arabidopsis thaliana by interacting with INDETERMINATE DOMAIN14(IDD14).In our genetic and biochemical experiments,overexpression of ICE1 greatly promoted both the activation of QQS and high pollen viability mediated by ***14 additively enhanced ICE1 function by promoting the binding of ICE1 to the QQS *** addition,mutation of ICE1 significantly repressed QQS expression;the impaired function of QQS and the abnormal anther dehiscence jointly affected pollen development of the ice1-2 *** results also showed that the enhancement of pollen activity by ICE1 depends on ***,QQS interacted with CUT1,the key enzyme for long-chain lipid *** interaction both promoted CUT1 activity and regulated pollen lipid metabolism,ultimately determining pollen hydration and *** results not only provide new insights into the key function of QQS in promoting pollen development by regulating pollen lipid metabolism,but also elucidate the mechanism that facilitates the transcription of QQS in this vital developmental process.

关键词： transcriptional metabolism jointly

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Associations of lens thickness and axial length with outcomes of laser peripheral iridotomy

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International Journal of Ophthalmology(English edition) 2021年第5期14卷 714-718页

作者： ya-Meng Liu Die Hu Long-Fang Zhou Jie Lan Cheng-Cheng Feng Xiao-Yun Wang Xiao-Jing Pan Weifang Medical University Weifang 261021Shandong ProvinceChina State Key Laboratory Cultivation Base Shandong Provincial Key Laboratory of OphthalmologyShandong Eye InstituteShandong First Medical University&Shandong Academy of Medical SciencesQingdao 266071Shandong ProvinceChina Qingdao Eye Hospital of Shandong First Medical University Qingdao 266071Shandong ProvinceChina

AIM:To investigate the association of axial length(AL),lens thickness(LT),and lens vault(LV)with postoperative anterior chamber angle metrics after laser peripheral iridotomy(LPI).METHODS:Prospective observational study of 69 patients(97 eyes)were diagnosed as primary angle-closure suspect(PACS),primary angle closure(PAC)or primary angle-closure glaucoma(PACg).AL,LT,anterior central chamber depth(ACD),angle opening distance(AOD),trabecular iris angle(tia),and angle recess area(ARA)were measured before and 1 wk after *** association between AL,LT,LV with ACD,AOD,tia,ARA were analyzed by comparing the differences between preoperative and postoperative measurements for anterior segment biometric ***:ACD,AOD,tia,and ARA were significantly increased after LPI(all Pgreater LT was significantly associated with greater postoperative increases in ACD,AOD,tia,and ARA(all Pgnificantly associated with changes of anterior segment biometric *** LV was significantly associated with greater postoperative increases in ACD,AOD,and tia(all Pgnificantly associated with changes of ***:greater baseline LT and LV measurements are associated with greater increases in anterior segment biometric parameters after laser peripheral *** are not associated with the change of anterior segment biometric parameters.

关键词： laser peripheral iridotomy primary angleclosure glaucoma lens thickness axial length anterior chamber angle metrics

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他汀类药物对Stanford B型主动脉夹层患者主动脉腔内修复术疗效的影响

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中国实用内科杂志 2017年第7期37卷 652-655页

作者：张磊刘艳杰王效增何瑞霞周铁楠王雅荆全民沈阳军区总医院心内科辽宁沈阳110016

目的观察他汀类药物对Stanford B型主动脉夹层患者行主动脉腔内修复术疗效的影响。方法回顾性分析2002年4月至2013年10月于沈阳军区总医院心血管内科住院治疗并行主动脉腔内修复术治疗的Stanford B型主动脉夹层患者388例,分析他汀组与... 详细信息

目的观察他汀类药物对Stanford B型主动脉夹层患者行主动脉腔内修复术疗效的影响。方法回顾性分析2002年4月至2013年10月于沈阳军区总医院心血管内科住院治疗并行主动脉腔内修复术治疗的Stanford B型主动脉夹层患者388例,分析他汀组与非他汀组临床特点及主动脉腔内修复术后围手术期及3年随访的死亡率、再次行主动脉腔内修复术等事件的发生率。结果 (1)两组患者临床资料比较:两组患者的性别、年龄及体重指数等无统计学意义(P均>0.05);他汀组与非他汀组患糖尿病、脑卒中的比例无统计学意义(P均>0.05);他汀组高血压病、冠心病的比例明显高于非他汀组(P均0.05)。(2)围手术期情况:两组患者植入支架的数目、长度、近远端直径及内漏的发生等差异均无统计学意义(P均>0.05);非他汀组完全封闭左锁骨下动脉的比例明显高于他汀组(P=0.020);两组患者围术期死亡、术后发热、脑卒中、肢体活动障碍及住院时间等差异均无统计学差异(P均>0.05);他汀组合并PCI的比例明显高于非他汀组(P0.05)。结论单中心研究未显示他汀类药物可以改善主动脉夹层患者行主动脉腔内修复术的近远期生存率。

关键词：他汀类药物主动脉夹层主动脉腔内修复术

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Hypermonones A-I,New Polyprenylated Acylphloroglucinols from Hypericum monogynum with Multidrug Resistance Reversal Activity

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Chinese Journal of Chemistry 2021年第9期39卷 2422-2432页

作者： yan-Rong Zeng ya-Nan Li Jue ya.g Ping Yi Lei Huang Lie-Jun Huang Wei gu Zhan-Xing Hu yan-Mei Li Chun-Mao Yuan Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyangGuizhou 550014China The Key Laboratory of Chemistry for Natural Products of guizhou Province and Chinese Academy of Sciences GuiyangGuizhou 550014China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

Eleven biogenetically related polyprenylated acylphloroglucinols(PPAPs),including four novel skeletons(1-4)and five new com-pounds(5-9),were isolated from the flowers of Hypericum *** A-D(1-4)represented the first example of a unique dilactone structure containing carbonyl bonded single 5-lactone and tricyclic γ-lactone *** structures were elucidated by NMR analysis,X-ray crystallography,and ECD ***,we revised the structure of hyperibrin B to hy perm on one I(9)via NMR an alysis,a qua ntum computational chemistry method,and hypothetic bios yn thetic con *** compounds(5,6,and 9)with significant MDR reversal activity(RF ranging from 61 to 223)were superior to the positive control verapamil(MCF-7/ADR,RF:53;Hepg2/ADRz RF:124).Mechanism study for compound 5 indicated that this compound could inhibit the function of P-gp tran sport rather tha n its expressi on,and the possible recog nition mechanism betwee n compo und 5 and P-gp was predicted by molecular docking.

关键词： Hypericum monogynum Phytochemistry Structure elucidation Biological activity Multidrug resistance reversal activity

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玉米昌7-2近缘系遗传多样性及其配合力分析

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河南农业大学学报 2008年第2期42卷 150-154页

作者：李潮海赵亚丽王小星王群杨青华汤继华河南农业大学农学院河南郑州450002

采用SSR分子标记和NCⅡ交配设计相结合的方法,研究了4个昌7-2近缘系的遗传多样性及其与Reid群的配合力和杂交组合的产量。并分析了它们之间的相关性.结果表明,4个昌7-2近缘系间存在遗传多样性,安昌7-2、甘昌7-2和新7红三者之间的遗传距... 详细信息

采用SSR分子标记和NCⅡ交配设计相结合的方法,研究了4个昌7-2近缘系的遗传多样性及其与Reid群的配合力和杂交组合的产量。并分析了它们之间的相关性.结果表明,4个昌7-2近缘系间存在遗传多样性,安昌7-2、甘昌7-2和新7红三者之间的遗传距离较近,而浚928与它们的遗传距离较远;4个昌7-2近缘系组配的杂交组合(F_1)的平均产量存在显著差异,浚928所配F_1的平均产量高于安昌7-2和甘昌7-2 F_1的平均产量,新7红所配F_1的平均产量低于安昌7-2和甘昌7-2 F_1的平均产量,且安昌7-2所配F_1的平均产量高于甘昌7-2 F_1的平均产量.各自交系的配合力效应与其产量结果基本一致;SSR分子标记遗传距离与杂交组合产量、特殊配合力与杂交组合产量之间均呈显著正相关,特殊配合力与遗传距离之间也呈正相关,但未达到显著水平.

关键词：玉米近缘系遗传多样性 SSR标记配合力

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等效小剂量瑞芬太尼和芬太尼对经口气管插管小儿血流动力学反应的比较

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实用儿科临床杂志 2008年第23期23卷 1815-1818页

作者：杨泉涌薛富善许亚超刘毅廖旭张雁鸣刘建华中国医学科学院北京协和医学院整形外科医院麻醉科北京100144

目的比较等效小剂量瑞芬太尼和芬太尼对经口气管插管小儿血流动力学反应的影响。方法选择择期行全身麻醉下整形外科手术的患儿100例,美国麻醉医师协会(ASA)Ⅰ级或Ⅱ级,随机平均分为2组:瑞芬太尼组(R组)和芬太尼组(F组),在丙泊酚麻醉诱... 详细信息

目的比较等效小剂量瑞芬太尼和芬太尼对经口气管插管小儿血流动力学反应的影响。方法选择择期行全身麻醉下整形外科手术的患儿100例,美国麻醉医师协会(ASA)Ⅰ级或Ⅱ级,随机平均分为2组:瑞芬太尼组(R组)和芬太尼组(F组),在丙泊酚麻醉诱导中采用盲法应用瑞芬太尼2μg/kg或芬太尼2μg/kg。采用直接喉镜经口气管插管。监测麻醉诱导前(基础值)、气管插管前即刻、气管插管即刻和气管插管1、2、3、4、5min时的血压(BP)和心率(HR),计算各观察时间点BP和HR相对于基础值的变化率,并计算二重指数(RPP)。结果2组BP和HR的基础值及气管插管时间均无显著性差异。与基础值比较,虽然气管插管导致F组的BP、HR、RPP及其观察期最大值显著增高,但R组气管插管时BP、HR、RPP及其观察期最大值均较基础值显著降低。观察期时间点的BP、HR、RPP及其最大值二组比较均有显著性差异,观察期时间点的收缩压(SBP)和HR变化率及观察期其最大变化率2组比较亦有显著性差异。观察期SBP和HR增加>基础值30%的发生率在F组显著高于R组;但观察期SBP和HR降低>基础值30%的发生率在R组显著高于F组。结论在小儿应用异丙酚静脉麻醉诱导时,联合应用等效小剂量瑞芬太尼较芬太尼更能有效抑制经口气管插管的血流动力学反应。芬太尼2μg/kg不足以完全抑制小儿经口气管插管的血流动力学反应。虽然瑞芬太尼2μg/kg能够完全消除小儿经口气管插管的血流动力学反应,但可导致更多不良的心血管功能抑制。

关键词：瑞芬太尼芬太尼全身麻醉经口气管插管血流动力学反应儿童

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电沉积Sn-Bi合金工艺的研究

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电镀与环保 2009年第5期29卷 12-15页

作者：黄樟平张亚辉陈刚邹天熬曾德长华南理工大学材料科学与工程学院广东广州510640 武汉理工大学资源与环境工程学院湖北武汉430070 广东怀集汽车配件制造有限责任公司广东肇庆526400

采用硫酸盐镀液在铜基体上电沉积Sn-Bi镀层,利用能谱仪(EDS)、扫描电子显微镜(SEM)和X射线衍射仪(XRD)研究了电沉积参数对镀层成分和微观结构的影响。结果表明:镀层中Sn的质量分数随着镀液中Sn的质量浓度的增大而增大,同时随着电流密度... 详细信息

采用硫酸盐镀液在铜基体上电沉积Sn-Bi镀层,利用能谱仪(EDS)、扫描电子显微镜(SEM)和X射线衍射仪(XRD)研究了电沉积参数对镀层成分和微观结构的影响。结果表明:镀层中Sn的质量分数随着镀液中Sn的质量浓度的增大而增大,同时随着电流密度的增大,Sn的质量分数不断减少;Sn-Bi镀层主要由四方晶系的Sn和菱形晶系的Bi组成;另外,研究发现电流密度对镀层形貌影响较大。

关键词：硫酸盐镀液 Sn—Bi镀层电沉积电流密度

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