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基于三维扫描的带肋钢筋-混凝土界面黏结失效精细有限元分析

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工程力学 2024年第S1期41卷 215-221页

作者：杨犇章子华周春恒王轩张振文宁波大学土木工程与地理环境学院宁波315211

钢筋与混凝土之间良好的界面黏结性能是二者协同工作的基础,对钢筋混凝土结构承载和安全极其重要。为了研究钢筋与混凝土之间的非线性黏结失效机理,考虑钢筋与混凝土之间的摩擦力和机械咬合力,以及月牙肋的表面特征,采用三维扫描的方式... 详细信息

钢筋与混凝土之间良好的界面黏结性能是二者协同工作的基础,对钢筋混凝土结构承载和安全极其重要。为了研究钢筋与混凝土之间的非线性黏结失效机理,考虑钢筋与混凝土之间的摩擦力和机械咬合力,以及月牙肋的表面特征,采用三维扫描的方式建立了带肋钢筋-混凝土三维精细有限元模型,并通过拔出试验对比验证了数值模型的准确性。在此基础上,研究了钢筋-混凝土界面黏结-滑移行为与破坏机理,讨论了该文所提方法的优势。结果表明:界面黏结强度随混凝土强度增大而线性增大;钢筋直径的增大会导致界面黏结强度逐渐减小,并导致试件破坏模式的改变;数值模拟结果与试验结果吻合较好,说明采用三维扫描建立的数值模型可以准确模拟筋材与混凝土之间的黏结失效行为,进而从细观层面上揭示界面黏结失效机理。

关键词：带肋钢筋混凝土黏结破坏三维扫描数值模拟

Propagation characteristics of vibration waves induced in surrounding rock by tunneling blasting

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Journal of Mountain Science 2017年第12期14卷 2620-2630页

作者： chen shi-hai hu shuai-wei zhang zi-hua wu jian huaqiao University Xiamen 361021China Fujian Research Centerfor Tunneling and Urban Underground Space Engineering Huaqiao UniversityXiamen 361020China

The effect of blasting vibration waves on surrounding rock and supporting structures is an important field in underground engineering. In this paper, the separation variable method is used to solve the displacement potential function for the propagation of the blasting vibration waves. In the axis coordinate system, the particle motion and stress change with axial distance, radial distance and time is obtained in surrounding rock. The peak particle velocity law in surrounding rock under different blast loads and surrounding rock parameters is *** addition, the particle vibration characteristics in the surrounding rock are studied using numerical simulations method. The results shows that the peak particle velocity in surrounding rock appears negative exponent attenuation with the increase of axial distance, but it appears positive and negative fluctuations in radial direction. This phenomenon is a new discovery and it has been rarely investigated before. Moreover, the peak particle velocity attenuates more quickly and intensely in the near blasting field,which means that the supporting structure in a shorter distance away from the heading face is vulnerable to the impact of blasting vibration. Theattenuation of blasting vibration velocity is closely related to charge length, blasting load amplitude,attenuation index and rock elastic modulus. The numerical simulation accomplishes the same results and then demonstrates the validity of theoretical results.

关键词： Tunneling blasting Blasting vibration wave Surrounding rock Wave equation Vibration velocity

掌叶覆盆子及其变种甜茶的质体基因组比较研究

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中国中药杂志 2024年第6期49卷 1506-1516页

作者：乔萍覃明孟婉姮汪奕衡闫滨滨张子华袁庆军孙嘉惠王升德兴市中医研究院试验培训基地江西德兴334213 中国中医科学院中药资源中心道地药材品质保障与资源持续利用全国重点实验室北京100700 甘肃省生态资源监测中心甘肃兰州730000

掌叶覆盆子Rubus chingii和甜茶*** ***是优质的“药食同源”特色植物,经济效益显著,发展前景广阔。为探讨掌叶覆盆子及其变种甜茶的遗传结构及进化特征差异,该研究利用Illumina HiSeq XTen测序平台对2物种质体全基因组进行测序、组装... 详细信息

掌叶覆盆子Rubus chingii和甜茶*** ***是优质的“药食同源”特色植物,经济效益显著,发展前景广阔。为探讨掌叶覆盆子及其变种甜茶的遗传结构及进化特征差异,该研究利用Illumina HiSeq XTen测序平台对2物种质体全基因组进行测序、组装、注释和特征分析,并采用生物信息学方法对其进行比较基因组分析和系统发育分析。结果表明,掌叶覆盆子和甜茶质体基因组呈现典型的环状四分体结构,由1个大单拷贝区(large single copy region,LSC)、1个小单拷贝区(small single copy region,LSC)和1对反向重复序列区(inverted repeat regions)组成。经比较分析,共鉴定出56个SSR位点,大部分由A和T组成。2个物种IR区边界基因结构保守,仅个别碱基差异。同时识别出3个高变区域:rps16⁃trnQ⁃psbK、trnR⁃at⁃pA和trnT⁃trnL,可作为潜在鉴定标记在未来进一步开发利用。基于最大似然法(maximum likelihood)与贝叶斯算法(Bayesian inference)所构建的系统发育分析结果显示,掌叶覆盆子和甜茶聚为一支,支持率达100%,两者最近缘物种为三花悬钩子***。该研究从质体基因组层面上明确了两者间的遗传差异,以上结果将为后续的物种保护与开发利用奠定基础。

关键词：掌叶覆盆子甜茶质体基因组高变片段系统发育

Influence of millisecond time,charge length and detonation velocity on blasting vibration

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Journal of Central South University 2015年第12期22卷 4787-4796页

作者：陈士海吴建张子华 College of Civil Engineering Huaqiao University State Key Laboratory of Disaster Prevention & Mitigation of Explosion & Impact College of Civil Engineering and Architecture Shandong University of Science and Technology

The law of blasting vibration caused by blasting in rock is very *** numerical methods cannot well characterize all the influencing factors in the blasting *** effects of millisecond time,charge length and detonation velocity on the blasting vibration are discussed by analyzing the characteristics of vibration wave generated by finite length cylindrical *** is found that in multi-hole millisecond blasting,blasting vibration superimpositions will occur several times within a certain distance from the explosion source due to the propagation velocity difference of P-wave and S-wave generated by a short column *** superimpositions will locally enlarge the peak velocity of blasting vibration *** magnitude and scope of the enlargement are closely related to the millisecond ***,the particle vibration displacement characteristics of rock under long cylindrical charge is *** results show that blasting vibration effect would no longer increase when the charge length increases to a certain *** indicates that the traditional simple calculation method using the maximum charge weight per delay interval to predict the effect of blasting vibration is ***,the effect of detonation velocity on blasting vibration is only limited in a certain velocity *** detonation velocity is greater than a certain value,the detonation velocity almost makes no impact on blasting vibration.

关键词： cylindrical charge millisecond blasting blasting vibration peak particle velocity displacement

Spherical Polyelectrolyte Brush Nanoreactor:Preparation of Hollow TiO_(2) Nanospheres and Characterization by Small Angle X-Ray Scattering

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Chinese Journal of Polymer Science 2024年第9期42卷 1393-1400,I0009页

作者： Yu-hua zhang zi-Yu zhang Xin Liu En-Guang Ma Jiang-Tao Guo Li Li Xu-Hong Guo State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou253023China Institute of Bast Fiber Crops&Center of Southern Economic Crops Chinese Academy of Agricultural SciencesChangsha410205China

Titanium dioxide(TiO_(2))hollow nanoparticles present significant potential for photocatalytic applications while their straightforward preparation with precise structure control is still *** work reports the approach to preparing tunable hollow TiO_(2) nanospheres by utilization of spherical polyelectrolyte brushes(SPB)as nanoreactors and *** the preparation,the evolution of the structure was characterized by small angle X-ray scattering(SAXS),and in combination with dynamic light scattering and transmission electron *** formation of TiO_(2) shell within the brush(SPB@TiO_(2))is confirmed by the significant increase of the electron density,and its internal structure has been analyzed by fitting SAXS data,which can be influenced by Titanium precursors and ammonia *** calcining SPB@TiO_(2) in a muffle furnace,hollow TiO_(2) nanospheres are produced,and their transition to the anatase crystal form is triggered,as confirmed by X-ray diffraction *** the advantages of their hollow structure,these TiO_(2) nanospheres exhibit exceptional catalytic degradation efficiency of methylene blue(MB),tetracycline(TC),and 2,4-dichlorophenoxyacetic acid(2,4-D),and also demonstrate excellent recyclability.

关键词： Spherical polyelectrolyte brush Nanoreactor Hollow titanium dioxide X-ray scattering

Shi-pi-xiao-ji formula suppresses hepatocellular carcinoma by reducing cellular stiffness through upregulation of acetyl-coA acetyltransferase 1

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2727-2741页

作者： Hui-Ying Jian zi-Cheng Liang huan Wen Zhen zhang Pu-hua Zeng Graduate School Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Hospital of Integrated Traditional Chinese and Western Cancer Research Institute of Hunan Academy of Traditional Chinese MedicineHunan Academy of Chinese MedicineChangsha 410006Hunan ProvinceChina

BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not ***,this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1(ACAT1)-regulated cellular *** a series of experiments,we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1,lowering the level of cholesterol in the cell membrane,and altering the cellular stiffness,which provides a new idea for the research of traditional Chinese medicine against *** To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of *** HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type *** apoptotic rate and proliferative,invasive,and migratory abilities of control and SPXJ-treated HCC cells were *** force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC *** membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection ***1 protein levels were estimated using western *** Compared with the vehicle group,SPXJ serum considerably reduced proliferation of HCC cells,increased stiffness and apoptosis of HCC cells,inhibited migration and invasion of HCC cells,decreased plasma membrane cholesterol levels,and upregulated ACAT1 protein ***,treatment of HCC cells with the water-soluble cholesterol promoted proliferation,migration,and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels,but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle *** SPXJ formula inhibited proliferation,invasion,and migration

关键词： Shi-pi-xiao-ji formula Hepatocellular carcinoma Cellular stiffness Plasma membrane cholesterol level AcetylcoA acetyltransferase 1

Pairs of thiol-substituted 1,2,4-triazole-based isomeric covalent inhibitors with tunable reactivity and selectivity

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Chinese Chemical Letters 2024年第7期35卷 329-335页

作者： Shiqi Xu zi Ye Shuang Shang Fengge Wang huan zhang Lianguo Chen Hao Lin Chen Chen Fang hua Chong-Jing zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of Active Substance Discovery and Druggability EvaluationInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study(BZ0150)Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China The First Affiliated Hospital of Wenzhou Medical University Wenzhou 325000China

Covalent bioactive compounds are successfully used in clinic and attracted intense research efforts in the fundamental study as well as drug *** advantageous effects of covalent compounds compared with non-covalent ones are highly dependent on electrophilic ***,electrophilic warheads with tunable reactivity and selectivity are highly demanded in fields of medicinal chemistry and chemical ***,we report a novel electrophilic warhead,chloromethyl group activated by thiol-substituted 1,2,***,a pair of regioisomers could be simultaneously occurred in the step of alkylation during the synthesis of this unique *** is a rare example that the alkylation could simultaneously generate these two separable regioisomers of 1,2,4-triazole at the nitrogen or sulfur *** covalent-working mechanism of this new warhead is confirmed by various chemoproteomics experiments including target identification and binding site ***,the reactivity and selectivity of this new electrophilic warhead could be efficiently tuned by virtue of stereo ***,one pair of regioisomers(19S and 19X)induced distinct modes of cell *** 19S could induce apoptosis of colon cancer cells while 19X could induce both apoptosis and ***,this study provides pairs of novel electrophilic warheads that could be useful not only in supporting the design of covalent compounds for drug discovery but also in providing chemical probes for the fundamental biological study.

关键词： Electrophilic warhead Covalent inhibitor 1,2,4-Triazole Chemical proteomics GSTO1

On the Pathwise Uniqueness of Solutions of One-dimensional Reflected Stochastic Differential Equations with Jumps

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 149-163页

作者： hua zhang School of Statistics and Data Science&Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang330013China

In this paper, we are concerned with the problem of the pathwise uniqueness of one-dimensional reflected stochastic differential equations with jumps under the assumption of non-Lipschitz continuous coefficients whose... 详细信息

关键词： reflected diffusion processes with jumps pathwise uniqueness local time Meyer It?'s formula

CNO^-浓度对W18Cr4V钢液体硫氮碳共渗速度及其组织性能的影响

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金属热处理 2005年第8期30卷 63-65页

作者：张自华王飚余贵华昆明理工大学机电工程学院云南昆明650093

叙述了W18Cr4V高速钢在无公害液体S、N、C共渗过程中,CNO-浓度高低对渗层深度、组织及性能的影响。试验结果表明,CNO-浓度在26%~37%范围内时,共渗速度随CNO-浓度的增加而加快,渗层硬度随CNO-浓度的升高而增加,渗层组织为氮的扩散层,而... 详细信息

叙述了W18Cr4V高速钢在无公害液体S、N、C共渗过程中,CNO-浓度高低对渗层深度、组织及性能的影响。试验结果表明,CNO-浓度在26%~37%范围内时,共渗速度随CNO-浓度的增加而加快,渗层硬度随CNO-浓度的升高而增加,渗层组织为氮的扩散层,而没有氮的化合物层;将共渗与回火复合为一道工序后,既节省了时间,又提高了零件的表面硬度,使用寿命比原来提高一倍。

关键词：液体硫氮碳共渗氰酸根渗速组织与性能