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内燃机与配件 2024年第13期 147-149页

作者：侯庆愉柳州城市职业学院广西柳州545036

目前,中国各个地区的多种行业领域对商用车的低温启动要求越来越高,所以本文重点对影响商用车低温启动的各项因素进行分析,结合商用车低温启动的需求提出了相应的完善措施,希望通过多种方法增强发动机在低温环境下的性能,从而实现低耗... 详细信息

目前,中国各个地区的多种行业领域对商用车的低温启动要求越来越高,所以本文重点对影响商用车低温启动的各项因素进行分析,结合商用车低温启动的需求提出了相应的完善措施,希望通过多种方法增强发动机在低温环境下的性能,从而实现低耗高效启动。

关键词：商用车低温启动加热

Integrable System and Motion of Curves in Projective and Similarity Geometries

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Communications in Theoretical Physics 2006年第1期45卷 45-48页

作者： hou yu-qing Department of Electronics Northwest University Xi＇an 710069 China

Based on the natural frame in the projective geometry, motions of curves in projective geometry are studied. It is shown that several integrable equations including Sawada-Kotera and KK equations arise from motion of plane curves in projective geometries. Motion of space curves described by acceleratlon field and governed by endowing an extra space variable in similarity geometry P^3 is also studied.

关键词： motion of curve similarity geometry projective geometry integrable equation

微塑料与农田土壤中典型污染物的复合污染研究进展

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环境科学 2024年第2期45卷 1196-1209页

作者：侯宇晴李冰王金花宋文慧王兰君王军朱鲁生山东农业大学资源与环境学院山东省高校农业环境重点实验室泰安271018

作为一种新型环境持久性污染物,微塑料除自身能够对生态系统产生不良影响外,其也可与周围环境中的共存污染物形成复合污染,从而产生更高的生态风险和健康风险.基于农业生态系统视角,聚焦重金属、农药和抗生素这3种农田土壤典型污染物与... 详细信息

作为一种新型环境持久性污染物,微塑料除自身能够对生态系统产生不良影响外,其也可与周围环境中的共存污染物形成复合污染,从而产生更高的生态风险和健康风险.基于农业生态系统视角,聚焦重金属、农药和抗生素这3种农田土壤典型污染物与微塑料的复合污染,综述了重金属、农药和抗生素在微塑料上的吸附-解吸行为,探讨了微塑料的结构与性质、污染物的理化性质以及环境条件对重金属、农药和抗生素在微塑料上吸附-解吸行为的影响,阐述了微塑料对农田土壤中重金属、农药和抗生素生物有效性的影响及内在机制,指出了当前研究存在的问题和不足并对未来研究方向进行了展望,可为微塑料与农田土壤典型污染物复合污染的生态风险评估提供科学参考.

关键词：土壤微塑料复合污染吸附-解吸生物有效性

Application of Rietveld Refinement to Investigate the High Chromium White Cast Iron Austempered at Different Temperatures

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Journal of Iron and Steel Research International 2009年第4期16卷 33-38页

作者： hou qing-yu HUANG Zhen-yi WANG Jing-tao School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094Jiangsu China School of Materials Science and Engineering Anhui University of TechnologyMa'anshan 243002 Anhui China

The effect of austempering temperature on the microstructure and properties of a high chromium white cast iron was investigated with the Rietveld refinement method. The result shows that the upper bainite exists in the sampie austempered at 623 K and the martensite, lower bainite, M7C3, and retained austenite exist in the samples austempered at 563 K and 593 K. The relative content of the retained austenite increases with increasing the austemper- ing temperature from 563 K to 623 K. The higher hardness, impact toughness and impact abrasive wear resistance can be obtained for the specimen austempered at 593 K.

关键词： high chromium white cast iron austempering retained austenite Rietveld refinement~ microstructurelproperties

High-Order Elastic Constants and Anharmonic Properties of NaBH_(4):First-Principles Calculations

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Chinese Physics Letters 2011年第7期28卷 236-238页

作者： ZHANG Xiao-Dong JIANG Zhen-Yi Zhou Bo hou Zhu-Feng hou yu-qing Institute of Modern Physics Northwest UniversityXi'an 710069 Department of Physics Fudan UniversityShanghai 200433 Department of Electronic Science Northwest UniversityXi'an 710069

We present theoretical studies for second-and third-order elastic constants in NaBH_(4) based on ab initio *** calculated second−order elastic constants agree well with available experimental *** anharmonic properties of NaBH_(4),such as pressure derivative of the second−order elastic constants and the Grüneisen constants for long-wavelength acoustic mode γ(q,j),are characterized using the third-order elastic constants.

关键词： constants NaBH_(4) constants

Coronary stenting does not improve the long-term cardiovascular outcome of patients with mild to moderate renal insufficiency

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Chinese Medical Journal 2009年第2期122卷 158-164页

作者： XIE Di hou yu-qing hou Fan-fan ZHANG Wei-ru LI Yong GUO Zhi-gang GUO Zhi-jian ZHANG Xun Division of Nephrology Nanfang Hospital Southern Medical University Guangzhou Guangdong 510515 China Division of Cardiology Nanfang Hospital Southern Medical University Guangzhou Guangdong 510515 China

Background Several studies have shown that coronary stenting reduces the frequency of clinical and angiographic restenosis in patients with mild to moderate renal insufficiency. However, less is known about the long-term benefits of stent use in this population. This study was aimed to determine the impact of coronary stenting on extended （5 years） long-term outcomes of patients with chronic renal insufficiency. Methods The study included 602 consecutive patients who underwent successful percutaneous coronary intervention with stenting. Renal insufficiency was defined as an estimated glomerular filtration rate 〈60 ***-1-｜.73 m-2. The major adverse cardiac events were compared for patients with （n=160） and without （n=442） renal insufficiency. Results After the third year of follow-up, nonfatal myocardial infarction and revascularization rates were significantly increased in patients with renal insufficiency compared with those without renal dysfunction （16.9% vs 7.7%, P=0.001; 29.4% vs 15.8%, P 〈0.001）. In patients who had recurrent cardiovascular events, a significantly higher rate of de novo stenosis revascularization was found in patients with renal insufficiency than without renal insufficiency （57.7% vs 22.7%, P 〈0.001）, while there was no significant difference in target lesion revascularization between the groups （51.9% vs 43.6%, P=0.323）. Multivariate analysis demonstrated an independent impact of the presence of renal insufficiency on the major adverse cardiac events （hazard ratio： 1.488, 95% confidence interval： 1.051-2.106, P=0.025） and de novo stenosis （hazard ratio： 5.505, 95% confidence interval： 2.151-14.090, P 〈0.001）. Conclusions The late major adverse cardiac events, after successful coronary stenting, is increased in patients with an estimated glomerular filtration rate 〈60 ***-1.1.73m-2. This might be associated with increased risk of de novo stenosis in this population. Chin Med J 2009; 122（2）： 158-164

关键词： long-term outcomes revascularization renal insufficiency stents

Biomimetic microchannel network with functional endothelium formed by sacrificial electrospun fibers inside 3D gelatin methacryloyl(GelMA)hydrogel models

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 79-96页

作者： Haoyu SUN Haiyang MA Li WANG Yang LIU Tian hou Wenjie TANG qing yu Meiwen AN Meiling WEN Institute of Biomedical Engineering College of Biomedical EngineeringTaiyuan University of TechnologyTaiyuan030024China

Three-dimensional(3D)hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration.A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular *** report describes the preparation of a biomimetic hydrogel scaffold with an internal microchannel network,using electrospinning techniques and the sacrificial template method for 3D cell *** and cavities were created within the gelatin methacryloyl(GelMA)hydrogel by sacrificing polyvinyl alcohol(PVA)electrospun fibers(>10µm),resulting in the creation of microvessel-like *** characterizations,swelling properties,and biodegradation analysis were conducted to investigate the feasibility of a biomimetic microchannel network hydrogel scaffold for 3D cell culture *** to pure GelMA hydrogel,the hydrogel with microchannels promoted cell proliferation,adhesion,and endothelial tube ***,the results confirmed that the biomimetic microchannel network scaffold had a major impact on the distribution and arrangement of human umbilical vein endothelial cells(HUVECs)and can enable the formation of artificial microvasculature by the culture of HUVECs and cell media perfusion.

关键词： Biomimetic scaffold Photocrosslinking Microchannel network Tissue engineering Artificial microvascular

A Strategy to Optimize the Oligo-Probes for Microarray-based Detection of Viruses

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中国病毒学 2007年第4期22卷 326-335页

作者： Zhuo Zhou Zhi-xun DOU Chen ZHANG hou-qing yu Yi-jie LIU Cui-zhu ZHANG You-jia CAO Department of Biochemistry and Molecular Biology College of Life Sciences Nankai University Tianjin 300071 China The Key Laboratory of Bioactive Materials Ministry of Education Nankai University Tianjin 300071 China School of Computing National University of Singapore 3 Science Drive 2 117543 Singapore Tianfin Key Laboratory of Microbial Functional Genomics College of Life Sciences Nankai University Tianjin 300071 China

DNA microarrays have been acknowledged to represent a promising approach for the detection of viral pathogens. However, the probes designed for current arrays could cover only part of the given viral variants, that could result in false-negative or ambiguous data. If all the variants are to be covered, the requirement for more probes would render much higher spot density and thus higher cost of the arrays. Here we have developed a new strategy for oligonucleotide probe design. Using type I human immunodeficiency virus (HIV-1) tat gene as an example, we designed the array probes and validated the optimized parameters in silico. Results show that the oligo number is significantly reduced comparing with the existing methods, while specificity and hybridization efficiency remain intact. The adoption of this method in reducing the oligo numbers could increase the detection capacity for DNA microarrays, and would significantly lower the manufacturing cost for making array chips.

关键词：探针微阵列检测病毒最优化寡核苷酸

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma yu hou Ba Li He-song Zhang qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

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第一性原理研究钨掺杂对锐钛矿物性的影响

物理学报 2015年第24期64卷 289-297页

作者：侯清玉赵春旺内蒙古工业大学理学院呼和浩特010051 上海海事大学文理学院上海201306

在实验上,W掺杂量在0.02083—0.04167的范围内时,有关掺杂体系的电导率影响的研究有两种相悖的结论.为解决这个问题,本文采用第一性原理平面波模守恒赝势方法,首先构建了两种Ti_(0.97917)W_(0.02083)O_2和Ti_(0.95833)W_(0.04167)O_2超... 详细信息

在实验上,W掺杂量在0.02083—0.04167的范围内时,有关掺杂体系的电导率影响的研究有两种相悖的结论.为解决这个问题,本文采用第一性原理平面波模守恒赝势方法,首先构建了两种Ti_(0.97917)W_(0.02083)O_2和Ti_(0.95833)W_(0.04167)O_2超胞模型,分别对这两种模型进行了几何结构优化、能带结构分布和态密度分布计算.同时还计算了掺杂体系的电子浓度、有效质量、迁移率和电导率.计算结果表明,在电子自旋极化或电子非自旋极化的条件下,W掺杂浓度越大、掺杂体系的电子浓度越大、有效质量越小、迁移率越小、电导率越大、导电性能越强.由电离能和Bohr半径分析进一步证实了Ti_(0.95833)W_(0.04167)O_2超胞的导电性能优于Ti_(0.97917)W_(0.02083)O_2超胞.为了研究掺杂体系的结构稳定性和形成能,又分别构建了Ti_(0.96875)W_(0.03125)O_2,Ti_(0.9375)W_(0.0625)O_2两种超胞模型,几何结构优化后进行了计算,结果表明,在电子自旋极化或电子非自旋极化的条件下,在W掺杂量为0.02083—0.04167的范围内,W掺杂浓度越大、掺杂体系的总能量越高、稳定性越差、形成能越大、掺杂越困难.将掺杂体系的晶格常数与纯的锐钛矿TiO_2相比较,发现沿a轴方向的晶格常数变大、沿c轴方向的晶格常数变小、掺杂体系的体积变大,计算结果与实验结果相符合.在电子自旋极化的条件下,掺杂体系形成了半金属化的室温铁磁性稀磁半导体.

关键词： W掺杂锐钛矿TiO2 物性第一性原理