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黄瓜籽防治骨质疏松症的古今应用及现代研究进展

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中华中医药杂志 2024年第2期39卷 874-877页

作者：宁梦真孙银玲丁纯洁郑宏宇赵娢陈丽艳黑龙江省中医科学院哈尔滨150036

黄瓜籽为葫芦科黄瓜属植物Cucumis sativus Linn.的干燥成熟种子,在民间常用于接骨壮骨,效果显著,收载于《辽宁常用中草药手册》和《中华本草》中,具有续筋接骨、祛风消痰的功效。近几年来,一些学者研究发现黄瓜籽通过促进去势骨质疏松... 详细信息

黄瓜籽为葫芦科黄瓜属植物Cucumis sativus Linn.的干燥成熟种子,在民间常用于接骨壮骨,效果显著,收载于《辽宁常用中草药手册》和《中华本草》中,具有续筋接骨、祛风消痰的功效。近几年来,一些学者研究发现黄瓜籽通过促进去势骨质疏松模型大鼠骨折愈合及骨骼重塑,减缓去势后骨质流失速度等机制达到防治骨质疏松的目的。另外,黄瓜籽中还含有多种潜在的抗骨质疏松作用成分,如植物甾醇、油酸、黄酮类成分及微量元素等,可通过多种作用机制发挥抗骨质疏松作用。此外,黄瓜籽还具有抗氧化、抗血栓、保护牙齿、调节肠道菌群及调节糖脂代谢等作用,由于菌群失调、糖脂代谢紊乱、氧化应激等都与骨质疏松密切相关,可进一步开展研究及开发利用。

关键词：黄瓜籽骨质疏松症古今应用研究进展成分药理作用

激光烧蚀方式对织构化球墨铸铁摩擦磨损性能的影响

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电镀与涂饰 2024年第7期43卷 68-75页

作者：纪成龙吕廓朱胜旺刘炜程王成金郑宏宇王志文山东理工大学山东淄博255000 山东盛迪医药有限公司山东济南250000

[目的]为提高球墨铸铁表面的耐磨性,分析了不同激光烧蚀方式对织构化球墨铸铁摩擦磨损性能的影响。[方法]采用传统激光逐点烧蚀方法在球墨铸铁表面直接制备规则的微织构阵列,以及采用激光连续扫描的方式在球墨铸铁表面原位诱导制备不规... 详细信息

[目的]为提高球墨铸铁表面的耐磨性,分析了不同激光烧蚀方式对织构化球墨铸铁摩擦磨损性能的影响。[方法]采用传统激光逐点烧蚀方法在球墨铸铁表面直接制备规则的微织构阵列,以及采用激光连续扫描的方式在球墨铸铁表面原位诱导制备不规则的微织构阵列,两种微织构阵列的平均直径和平均面密度保持相同,随后在油润滑条件下进行摩擦磨损试验。通过表面硬度、表面成分、摩擦因数、磨损率等检测,探讨了两种织构化球墨铸铁表面的减摩抗磨性能及机理。[结果]激光逐点烧蚀方式未能提升球墨铸铁的表面硬度,摩擦因数和磨损率分别比原始样件减小9.3%和75%,摩擦磨损试验后表面发生了明显氧化。激光连续扫描方式将球墨铸铁表面硬度由(273±25)HV提升至(428±36)HV,摩擦因数和磨损率分别比原始样件减小20%和78%,摩擦磨损试验后表面未发生明显氧化。[结论]相比逐点烧蚀微织构试样,激光连续扫描制备的微织构样品表面的减摩抗磨性能更优异,同时减少了摩擦时产生犁沟、塑性变形、磨损碎屑等现象,其摩擦学性能的提高归因于非织构区域表面硬度的提高,以及微织构对磨粒的捕捉、储油及动压润滑效应的协同作用。

关键词：球墨铸铁微织构激光烧蚀原位诱导机理摩擦学

Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths

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International Journal of Mining Science and Technology 2024年第1期34卷 117-136页

作者： Zhi zheng hongyu Xu Kai Zhang Guangliang Feng Qiang Zhang Yufei Zhao State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100080China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing ***,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is *** triaxial static compression and intermittent disturbance tests are carried out on *** effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture *** increases in microseismic parameters during rock loading can be precursors for intermittent rock *** on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental *** sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are *** study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads.

关键词： True triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect Fractional mechanical model

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重卡变速器齿轮螺旋角修形设计与试验

汽车实用技术 2024年第16期49卷 56-60页

作者：郑鸿宇韩雨苏天俊高晓阳杨泽凯陕西法士特汽车传动集团有限公司陕西西安710100

针对重卡变速器齿轮接触普遍出现的偏载现象,文章提出了一种变速箱齿轮螺旋角修形方法,通过调整齿轮螺旋角修形斜度以及改变螺旋角大小,改善齿轮接触偏载现象。以重卡12挡变速箱为研究对象,利用有限元仿真对齿轮副进行了数值模拟,并开... 详细信息

针对重卡变速器齿轮接触普遍出现的偏载现象,文章提出了一种变速箱齿轮螺旋角修形方法,通过调整齿轮螺旋角修形斜度以及改变螺旋角大小,改善齿轮接触偏载现象。以重卡12挡变速箱为研究对象,利用有限元仿真对齿轮副进行了数值模拟,并开展了接触斑试验、噪声试验和疲劳试验。结果表明,改进后的齿面接触应力分布均匀,接触斑居中,噪声无明显变化且仍满足疲劳试验要求,说明变速箱齿轮副的接触状况得到有效改善,验证了所提修形方法的可行性。该研究为重卡变速器偏载齿轮修正提供了理论依据与试验参考。

关键词：变速器齿轮螺旋角齿向修形接触斑点

Dual Extended Kalman Filter for Combined Estimation of Vehicle State and Road Friction

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 313-324页

作者： ZONG Changfu HU Dan zheng hongyu State Key Laboratory of Automotive Simulation and Control Jilin University

Vehicle state and tire-road adhesion are of great use and importance to vehicle active safety control systems. However, it is always not easy to obtain the information with high accuracy and low expense. Recently, many estimation methods have been put forward to solve such problems, in which Kalman filter becomes one of the most popular techniques. Nevertheless, the use of complicated model always leads to poor real-time estimation while the role of road friction coefficient is often ignored. For the purpose of enhancing the real time performance of the algorithm and pursuing precise estimation of vehicle states, a model-based estimator is proposed to conduct combined estimation of vehicle states and road friction coefficients. The estimator is designed based on a three-DOF vehicle model coupled with the Highway Safety Research Institute（HSRI） tire model; the dual extended Kalman filter （DEKF） technique is employed, which can be regarded as two extended Kalman filters operating and communicating simultaneously. Effectiveness of the estimation is firstly examined by comparing the outputs of the estimator with the responses of the vehicle model in CarSim under three typical road adhesion conditions（high-friction, low-friction, and joint-friction）. On this basis, driving simulator experiments are carried out to further investigate the practical application of the estimator. Numerical results from CarSim and driving simulator both demonstrate that the estimator designed is capable of estimating the vehicle states and road friction coefficient with reasonable accuracy. The DEKF-based estimator proposed provides the essential information for the vehicle active control system with low expense and decent precision, and offers the possibility of real car application in future.

关键词： vehicle state road friction coefficient estimation dual extended Kalman filter (DEKF)

Femtosecond laser-induced surface wettability modification of polystyrene surface

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Science China(Physics,Mechanics & Astronomy) 2016年第12期59卷 47-51页

作者： Bing Wang XinCai Wang hongyu zheng YeeCheong Lam SIMTech-NTUJoint Laboratory(Precision Machining) Nanyang Technological UniversitySingapore 639798Singapore School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Singapore Institute of Manufacturing Technology(SIMTech) Singapore 138634Singapore

In this paper, we demonstrated a simple method to create either a hydrophilic or hydrophobic surface. With femtosecond laser irradiation at different laser parameters, the water contact angle (WCA) on polystyrene’s surface can be modified to either 12.7° or 156.2° from its original WCA of 88.2°. With properly spaced micro-pits created, the surface became hydrophilic probably due to the spread of the water droplets into the micro-pits. While with properly spaced micro-grooves created, the surface became rough and more hydrophobic. We investigated the effect of laser parameters on WCAs and analyzed the laser-treated surface roughness, profiles and chemical bonds by surface profilometer, scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). For the laser-treated surface with low roughness, the polar (such as C—O, C=O, and O—C=O bonds) and non-polar (such as C—C or C—H bonds) groups were found to be responsible for the wettability changes. While for a rough surface, the surface roughness or the surface topography structure played a more significant role in the changes of the surface WCA. The mechanisms involved in the laser surface wettability modification process were discussed.

关键词： femtosecond 激光聚苯乙烯(PS ) wettability 微坑与密纹表面 texturing 和表面修正

Identification and functional verification of Y-chromosome-specific gene typo-gyf in Bactrocera dorsalis

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Insect Science 2024年第4期31卷 1270-1284页

作者： Peipei Liu Shuning Yu Wenping zheng Qiuyuan Zhang Jiao Qiao Ziniu Li Zhurong Deng hongyu Zhang National Key Laboratory for Germplasm Innovation and Utilization for Fruit and Vegetable Horticultural Crops Hubei Hongshan LaboratoryChina-Australia Joint Research Centre for Horticultural and Urban PestsInstitute of Urban and Horticultural EntomologyCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina

Genes on the Y chromosome play important roles in male sex determination and *** identification of Y-chromosome-specific genes not only provides a theoretical basis for the study of male reproductive development,but also offers genetic control targets for agricultural ***,Y-chromosome genes are rarely characterized due to their high repeatability and high heterochromatinization,especially in the oriental fruit *** this study,1011 Y-chromosome-specific candidate sequences were screened from 2 to 4 h Bactrocera dorsalis embryo datasets with the chromosome quotient method,6 of which were identified as Y-chromosome-specific sequences by polymerase chain reaction,including typo-gyf,a 19126-bp DNA sequence containing a 575-amino acid open reading *** deformation and a significant reduction in sperm number were observed after typo-gyf knockdown with RNA interference in *** typo-gyf knockout with clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 in the embryonic stage,the sex ratio of the emergent adults was unbalanced,with far more females than males.A genotype analysis of these females with the Y-chromosome gene MoY revealed no sex ***-gyf knockout led to the death of XY individuals in the embryonic *** conclude that typo-gyf is an essential gene for male survival,and is also involved in testicular development and *** identification of typo-gyf and its functional verification provide insight into the roles of Y-chromosome genes in male development.

关键词： Bactrocera dorsalis spermatogenesis testis typo-gyf gene Y-specific gene

Laser sintering of Cu nanoparticles on PET polymer substrate for printed electronics at different wavelengths and process conditions

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Frontiers of Mechanical Engineering 2020年第2期15卷 303-318页

作者： Juan Carlos HERNANDEZ-CASTANEDA Boon Keng LOK hongyu zheng Singapore Institute of Manufacturing Technology Singapore 138634Singapore School of Mechanical Engineering Shandong University of TechnologyZibo 255049China

This study explores the feasibility of different laser systems to sinter screen-printed lines from nonconductive copper nanoparticles(Cu NPs)on polyethylene terephthalate polymer *** materials are commonly used in manufacturing functional printed electronics for large-area ***,optical and thermal characterization of the materials is conducted to identify suitable laser sources and process *** diode(808 nm),Nd:YAG(1064 nm and second harmonic of 532 nm),and ytterbium fiber(1070 nm)lasers are *** parameters for sintering the Cu NPs are identified for each laser system,which targets low resistivity and high processing ***,the quality of the sintered tracks is quantified,and the laser sintering mechanisms observed under different wavelengths are *** considerations are discussed to improve the laser sintering process of Cu NPs.

关键词： laser sintering copper nanoparticles printed electronics

Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis:Important roles of microstructures and electronic modulation

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Carbon Energy 2024年第5期6卷 1-14页

作者： hongyu Gong Guanliang Sun Wenhua Shi Dongwei Li Xiangjun zheng Huan Shi Xiu Liang Ruizhi Yang Changzhou Yuan Department of New Energy Materials School of Environmental and Chemical EngineeringJiangsu University of Science and TechnologyZhenjiangJiangsuChina Advanced Materials Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandongChina Shandong Saikesaisi Hydrogen Energy Co. Ltd.JinanShandongChina Department of Materials Science and Engineering School of Materials Science&EngineeringUniversity of JinanJinanShandongChina Department of New Energy Science and Engineering College of EnergySoochow Institute for Energy and Materials InnovationsSoochow UniversitySuzhouJiangsuChina

Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable ***,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au nanoparticles(NPs)(denoted as HP-Au@CoxSy@ZIF-67)hybrid is synthesized by low-temperature sulfuration *** well-defined macroporous-mesoporous-microporous structure is obtained based on the combination of polystyrene spheres,as-formed CoxSy nanosheets,and ZIF-67 *** novel three-dimensional hierarchical structure significantly enlarges the three-phase interfaces,accelerating the mass transfer and exposing the active centers for oxygen evolution *** electronic structure of Co is modulated by Au through charge transfer,and a series of experiments,together with theoretical analysis,is performed to ascertain the electronic modulation of Co by ***,HP-Au@CoxSy@ZIF-67 catalysts with different amounts of Au were synthesized,wherein Au and NaBH4 reductant result in an interesting“competition effect”to regulate the relative ratio of Co^(2+)/Co^(3+),and moderate Au assists the electrochemical performance to reach the highest ***,the optimized HP-Au@CoxSy@ZIF-67 exhibits a low overpotential of 340 mV at 10 mA cm^(-2)and a Tafel slope of 42 mV dec-1 for OER in 0.1 M aqueous KOH,enabling efficient water splitting and Zn-air battery *** work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts.

关键词： Au nanoparticles cobalt sulfide electronic modulation hierarchical porous structure oxygen evolution reaction