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Journal of Thermal Science 2020年第4期29卷 1076-1084页

作者： cao Qun CUI Zheng Institute of Thermal Science and Technology Shandong UniversityJinan 250061China

Nanostructures on heat transfer surfaces can enhance micro/nanoscale phase-change heat transfer processes. To understand the enhancement mechanisms provided by nanostructures, evaporation processes of nanoscale liquid films on periodic sinusoidal-shaped surfaces were investigated via molecular dynamics simulations. By changing the amplitudes(A) and periods(T) of the curves describing the sinusoidal shapes, which possess shapes similar to f(x)=h0+Asin(2πx/T), sinusoidal surfaces of different sizes were constructed. An unevaporated region always existed on the copper plate for all surfaces during phase-change processes. Moreover, we calculated the interfacial thermal resistances and the mismatches between the vibrational density of states of the solid and liquid for different surfaces. The results show that the argon temperature changes and evaporation rates during the phase-change process on sinusoidal surfaces are higher than those on flat surfaces, and these results increase with the increase in amplitudes and the decrease in periods within certain limits mainly because of the thermal resistance decrease at the solid-liquid interface. Furthermore, the corresponding mismatches between the vibrational density of states of the solid and liquid also decrease, which indicates that the existence of sinusoidal nanostructures enhances the heat transfer of the phase-change process.

关键词： molecular dynamics simulation sinusoidal surface phase-change interfacial thermal resistance nanoscale

New heat Treatment Technology for Grain Refining of Structural Steel

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Journal of Iron and Steel Research International 2005年第6期12卷 49-53页

作者： lü Bo ZhANG Fu-cheng cao Guo-hua ZhANG Ji-ming Yanshan University Qinhuangdao 066004 China Key laboratory of Metastable MaterialsScience and Technology Qinhuangdao 066004 China）

The application of electrical contact heating （ECh） in austenitic grain refining of ultra-pure 42CrMoVNb steel was introduced. The ECh equipment was designed to reach uniform heating of uniform heat transfer in the sample. The 42CrMoVNb steel treated possesses uniform microstructure with an average austenite grain size of 1.4 μm, higher strength （1 538 MPa） and impact toughness （81J/cm^2）.

关键词： electrical contact heating medium carbon alloy steel ultrafine grain 42CrMoVNb

Element geochemical characteristics of a soil profile developed on dolostone in central Guizhou, southern China: implications for parent materials

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Acta Geochimica 2016年第4期35卷 445-462页

作者： Xingxing cao Pan Wu Zhenxing cao College of Resource and Environmental Engineering Guizhou University Graduate School of Science and Technology Shizuoka University

This study presents bulk chemical compositions of the Tongmuling soil profile, which developed on dolostone, and the overlying strata covering the bedrock in the central Guizhou province(southern China). The chemical weathering characteristics of the studied profile were investigated and the inheritance relationships between the terra rossa and overlying strata were discussed. The results show that there is no remarkable variation in the major elements and weathering indices from the rock–soil interface to the topsoil, indicating that the studied profile was not typical for in situ crustal chemical weathering. The terra rossa were mainly composed of Si O_2, Al_2O_3 and Fe_2O_3. Compared with the insoluble residues and overlying strata, the terra rossa are characterized by an enrichment of Y and Cs and depletion of Ba and Sr. The subsoil shows a notable Ce negative anomaly, characterized by heavy rare earth element enrichment(l/h = 1.55–3.74), whereas the topsoil shows a positive Ce anomaly with light rare earth element enrichment(l/h = 5.93–9.14). According to laterite-forming capacity estimates, the terra rossa could not have only been formed from acid-insoluble residues from the bedrock; Al_2O_3 versus Fe_2O_3and Nb plotted against Ta show significant positive correlations between the terra rossa and overlying strata. The Eu/Eu* versusGd_N/Yb_Nand ternary diagrams for Sc, Th, Zr, and Ta suggest that the overlying strata could also provide parent materials for the genesis of terra rossa.

关键词： Terra rossa Dolomite Parent materials Guizhou China

Weak rigid monoidal category

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Frontiers of Mathematics in China 2017年第1期12卷 19-33页

作者： haijun cao School of Science Shandong Jiaotong University Jinan 250375 China

We define the right regular dual of an object X in a monoidal category l, and give several results regarding the weak rigid monoidal category. Based on the definition of the right regular dual, we construct a weak hopf algebra structure of h = End（F） whenever （F, J） is a fiber functor from category l to Vec and every X ∈ l has a right regular dual. To conclude, we give a weak reconstruction theorem for a kind of weak hopf algebra.

关键词： Semilattice graded weak hopf algebra regular right dual weak rigid monoidal category

Consistent Alterations of human Fecal Microbes After Transplantation into Germ-free Mice

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Genomics, Proteomics & Bioinformatics 2022年第2期20卷 382-393页

作者： Yanze li Wenming cao Na l Gao Xing-Ming Zhao Wei-hua Chen MOE Key laboratory of Molecular Biophysics Hubei Key Laboratory of Bioinformatics and Molecular-imagingDepartment of Bioinformatics and Systems BiologyCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Institute of Science and Technology for Brain-Inspired Intelligence(ISTBI) Fudan UniversityShanghai 200433China College of life Science Henan Normal UniversityXinxiang 453007China

Fecal microbiota transplantation(FMT)of human fecal samples into germ-free(GF)mice is useful for establishing causal relationships between the gut microbiota and human ***,due to the intrinsic differences between human and mouse intestines and the different diets of the two organisms,it may not be possible to replicate human phenotypes in mice through FMT;similarly,treatments that are effective in mouse models may not be effective in *** this study,we aimed to identify human gut microbes that undergo significant and consistent changes(i.e.,in relative abundances)after transplantation into GF mice in multiple experimental *** collected 16S rDNA-seq data from four published studies and analyzed the gut microbiota profiles from 1713 human–mouse ***,on average,we found that only 47%of the human gut microbes could be re-established in mice at the species level,among which more than 1/3 underwent significant changes(referred to as“variable taxa”).Most of the human gut microbes that underwent significant changes were consistent across multiple human–mouse pairs and experimental ***,about 1/3 of human samples changed their enterotypes,i.e.,significant changes in their leading species after *** fed with a controlled diet showed a lower enterotype change rate(23.5%)than those fed with a noncontrolled diet(49.0%),suggesting a possible solution for *** of the variable taxa have been reported to be implicated in human diseases,with some recognized as the causative *** results highlight the challenges of using a mouse model to replicate human gut microbiota-associated phenotypes,provide useful information for researchers using mice in gut microbiota studies,and call for additional validations after *** online database named FMT-DB is publicly available at http://***/#/.

关键词： Germ-free mice Fecal microbiota transplantation Gut microbe Enterotype 16S rDNA

Review on hydrogen Embrittlement of Press-hardened Steels for Automotive Applications

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Acta Metallurgica Sinica(English letters) 2023年第7期36卷 1123-1143页

作者： Z.Wang Q.lu Z.h.cao h.Chen M.X.huang J.F.Wang General Motors China Science lab Shanghai201206China Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong Kong999077China Key laboratory for Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing100084China

Press-hardened steel(PhS)with an ultimate tensile strength(UTS)of 1500 MPa has been widely used in automotive body-in-white in the last two decades,due to its ultra-high strength and excellent formability that is achieved by hot stamping ***,the application of PhS with UTS exceeding 1500 MPa in automotive industry could be deferred due to the increased risk of hydrogen *** reduce this kind of risk,recent research efforts have been focused on various ways to optimize the microstructure of *** present review intends to summarize these efforts,to highlight present solutions to address hydrogen embrittlement,and to shed light on directions for future *** influence of microstructure on the hydrogen embrittlement of PhS has been discussed in terms of both the steel substrate and the surface *** substrate part covers the influence of martensite,carbides,inclusions,and retained austenite,while the surface part covers decarburization and oxidation,pre-coating,and trimming.

关键词： hot stamping Press-hardened steels Coating-free hydrogen embrittlement Fracture Al-Si coating

Mesoscopic-Scale Numerical Investigation Including the Influence of Process Parameters on lPBF Multi-layer Multi-Path Formation

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 5-23页

作者： liu cao Institute for Systems Rheology School of Mechanical and Electrical EngineeringGuangzhou UniversityGuangzhou Higher Education Mega CenterGuangzhou510006China

As a typical laser additive manufacturing technology,laser powder bed fusion(lPBF)has achieved demonstration applications in aerospace,biomedical and other ***,how to select process parameters quickly and reasonably is still themain concern of lPBF *** order to quantitatively analyze the influence of different process parameters(laser power,scanning speed,hatch space and layer thickness)on the lPBF process,the multilayer and multi-path forming process of lPBF was predicted based on the open-source discrete element method framework Yade and the open-source finite volume method framework *** on the design of experiments method,a four-factor three-level orthogonal test scheme was designed,and the porosity and surface roughness data of each calculation scheme were *** analyzing the orthogonal test data,it was found that as the laser power increased,the porosity decreased,and as the scanning speed,hatch space,and layer thickness increased,the porosity *** addition,the influence of laser power and scanning speed on surface roughness showed a trend of decreasing first and then increasing,while the influence of scanning distance and layer thickness on surface roughness showed amonotonous increasing *** order of the influence of each process parameter on porosity was:scanning speed>laying thickness>laser power>hatch space,and the order of the influence of each process parameter on surface roughness was:hatch space>layer thickness>laser power>scanning *** the porosity of the part is most sensitive to scanning speed,and the surface roughness is the most sensitive to hatch *** above conclusions are expected to provide process control basis for actual lPBF production of the 316l stainless steel alloy.

关键词： laser powder bed fusion process parameter porosity surface roughness orthogonal test method numerical simulation

环状RNA ChACR调控压力超负荷诱导心肌肥大和氧化应激损伤

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中国组织工程研究 2025年第25期29卷 5362-5373页

作者：王霜韩瑜袁敏曹济民孙腾山西医科大学细胞生理学教育部重点实验室山西省细胞生理学重点实验室山西医科大学基础医学院生理学系山西省太原市030001

背景:病理性心肌肥大是多种心脏疾病的危险促进因素,但其发病机制仍未阐明。环状RNA与心肌肥大密切相关,然而环状RNA ChACR在心肌肥大中的作用及调控机制尚未见报道。目的:探究环状RNA ChACR在压力超负荷诱导心肌肥大中的作用及机制。方... 详细信息

背景:病理性心肌肥大是多种心脏疾病的危险促进因素,但其发病机制仍未阐明。环状RNA与心肌肥大密切相关,然而环状RNA ChACR在心肌肥大中的作用及调控机制尚未见报道。目的:探究环状RNA ChACR在压力超负荷诱导心肌肥大中的作用及机制。方法:①心脏原位注射环状RNA ChACR过表达慢病毒1周后进行横向主动脉缩窄手术诱导小鼠心肌肥大。术后8周,计算心脏质量/胫骨长比值和肺质量/胫骨长比值,测量心肌细胞表面积,检测肥大标志基因表达水平和心肌纤维化程度,评估心功能。②h9c2心肌细胞给予环状RNA ChACR过表达慢病毒处理72 h,然后加入1μmol/l血管紧张素Ⅱ处理24 h诱导心肌细胞肥大。通过检测心肌细胞表面积、肥大标志基因表达水平、蛋白质/DNA比值评估细胞肥大情况,通过检测活性氧水平和线粒体膜电位评估氧化应激损伤情况。结果与结论:①在体内和体外心肌肥大模型中,环状RNA ChACR的表达水平均显著降低(PhACR显著抑制了横向主动脉缩窄手术诱导的小鼠心肌肥大表型,主要表现为心脏体积减小、心脏质量/胫骨长比值显著降低(PhACR显著抑制了横向主动脉缩窄手术诱导的小鼠心脏纤维化,表现为纤维化面积减小(PhACR显著改善了小鼠心功能,主要表现为射血分数(PhACR显著抑制了血管紧张素Ⅱ诱导的心肌细胞肥大,主要表现为心肌细胞表面积显著减小(PhACR显著抑制了血管紧张素Ⅱ诱导的活性氧水平升高(PhACR在体内和体外心肌肥大模型中表达水平显著降低,过表达环状RNA ChACR显著抑制心肌肥大,减轻心肌纤维化,改善心功能,并且显著减轻了血管紧张素Ⅱ诱导的心肌细胞氧化应激损伤。

关键词：心肌肥大环状RNA ChACR 血管紧张素Ⅱ 横向主动脉缩窄手术氧化应激损伤

liouville Type Theorem About p-harmonic Function and p-harmonic Map with Finite l^q-Energy

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Chinese Annals of Mathematics,Series B 2017年第5期38卷 1071-1076页

作者： Xiangzhi cao School of Mathematics and Statistics Wuhan University Wuhan 430072 China

This paper deals with the p-harmonic function on a complete non-compact submanifold M isometrically immersed in an(n + k)-dimensional complete Riemannian manifold M of non-negative(n-1)-th Ricci curvature. The liouville type theorem about the p-harmonic map with finite l^q-energy from complete submanifold in a partially nonnegatively curved manifold to non-positively curved manifold is also obtained.

关键词： p-harmonic map p-harmonic map Kato inequality Index liouvilletheorem

Controlling synthesis and host sensitized Eu^(3+) emissions of K_5Gd_9F_(32) and GdF_3

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Science China(Technological Sciences) 2015年第5期58卷 899-906页

作者： XIE An cao ChunYan cao RenPing NOh hyeonMi JEONG Junghyun School of Materials Science and Engineering Xiamen University of Technology College of Mathematics and Physics Jinggangshan University Department of Physics Pukyong National University

By controlling the reactant ratios, hydrothermal time, hydrothermal temperatures, p h values of the prepared solutions, and the concentrations of K3C6h5O7·2h2O, 1 mol% Eu3+ doped cubic phase of K5Gd9F32 and/or orthorhombic phase of Gd F3 micro/nanocrystals have been synthesized based on a hydrothermal method. For comparison, the sample was also synthesized by a co-precipitation method. The samples were characterized by X-ray diffraction(XRD) patterns, field emission scanning electron microscopy(FE-SEM) images, energy-dispersive spectroscopy(EDS) spectra, and photoluminescence(Pl) excitation and emission spectra. By host Gd3+ sensitizing, the Eu3+ presents relatively strong emissions. The energy transfers from host Gd3+ to doping Eu3+ are observed in all the samples and the energy transfer plays an important role in the emission of Eu3+. Acting as a probe, the Eu3+ presents its distinct optical properties in the samples.

关键词： hydrothermal sensitized reactant cubic crystalline emissions dispersive doping excitation orthorhombic