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基于拉曼技术的高地钩叶藤导管壁化学成分微区分布研究

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西北林学院学报 2024年第2期39卷 203-209页

作者：汪佑宏余林鹏张菲菲杨明亮江泽慧马建锋田根林安徽农业大学林学与园林学院安徽合肥230036 黄山华塑新材料科技有限公司安徽黄山245900 国际竹藤中心北京100102

为探寻棕榈藤材具有优良韧性的机理和棕榈藤材高值化利用,选择高地钩叶藤为研究对象,利用显微共聚焦拉曼技术,对导管壁化学成分的微区分布进行测试分析。结果表明,高地钩叶藤导管壁纤维素分子浓度为次生壁>复合胞间层>细胞角隅,而木质... 详细信息

为探寻棕榈藤材具有优良韧性的机理和棕榈藤材高值化利用,选择高地钩叶藤为研究对象,利用显微共聚焦拉曼技术,对导管壁化学成分的微区分布进行测试分析。结果表明,高地钩叶藤导管壁纤维素分子浓度为次生壁>复合胞间层>细胞角隅,而木质素分子浓度分布恰好相反。次生壁内、外层纤维素、木质素及半纤维素分子浓度差异较小。在藤茎径向上,藤芯处导管次生壁中层和细胞角隅处木质素的分子浓度最高,藤皮处导管的半纤维素分子浓度最高。藤皮处导管次生壁中层纤维素的分子浓度最低而细胞角隅处却最高,而藤中与藤芯处导管细胞角隅中半纤维的分子浓度均很小。在藤茎轴向上,随着高度增加藤皮导管次生壁中层木质素和半纤维素分子浓度变化趋势相同,而纤维素分子浓度在藤皮与藤芯间变化趋势完全相反。除导管各壁层的三大素分布呈一定规律性外,在藤茎径向和轴向上规律不明显。

关键词：高地钩叶藤导管细胞壁成分拉曼光谱化学成分微区分布

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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou ze-chen Du Xiao Wang hui-ling jiang Qiang Zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

AP-1 and SP1 trans-activate the expression of hepatic CYP1A1 and CYP2A6 in the bioactivation of AFB1 in chicken

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Science China(Life Sciences) 2024年第7期67卷 1468-1478页

作者： jiang Deng Jia-Cheng Yang Yue Feng ze-Jing Xu Kamil Kuča Meng Liu Lv-hui Sun State Key Laboratory of Agricultural Microbiology Hubei Hongshan LaboratoryFrontiers Science Center for Animal Breeding and Sustainable ProductionCollege of Animal Sciences and TechnologyHuazhong Agricultural UniversityWuhan 430070China Department of Chemistry Faculty of ScienceUniversity of Hradec KraloveHradec Kralove 50003Czech Republic

Dietary exposure to aflatoxin B1(AFB1)is harmful to the health and performance of domestic *** hepatic cytochrome P450s(CYPs),CYP1A1 and CYP2A6,are the primary enzymes responsible for the bioactivation of AFB1to the highly toxic exo-AFB1-8,9-epoxide(AFBO)in ***,the transcriptional regulation mechanism of these CYP genes in the liver of chicks in AFB1metabolism remains ***-luciferase reporter assay,bioinformatics and site-directed mutation results indicated that specificity protein 1(SP1)and activator protein-1(AP-1)motifs were located in the core region-1,063/-948,-606/-541 of the CYP1A1 promoter as well as-636/-595,-503/-462,-147/-1 of the CYP2A6 ***,overexpression and decoy oligodeoxynucleotide technologies demonstrated that SP1 and AP-1 were pivotal transcriptional activators regulating the promoter activity of CYP1A1 and ***,bioactivation of AFB1to AFBO could be increased by upregulation of CYP1A1 and CYP2A6 expression,which was trans-activated owing to the upregulation of AP-1,rather than SP1,stimulated by AFB1-induced reactive oxygen ***,nano-selenium could reduce ROS,downregulate AP-1 expression and then decrease the expression of CYP1A1 and CYP2A6,thus alleviating the toxicity of *** conclusion,AP-1 and SP1 played important roles in the transactivation of CYP1A1 and CYP2A6 expression and further bioactivated AFB1to AFBO in chicken liver,which could provide novel targets for the remediation of aflatoxicosis in chicks.

关键词： aflatoxin B1 CYP1A1 CYP2A6 SP1 AP-1 transcriptional activation

Growth of Ag/g-C_(3)N_(4) nanocomposites on nickel foam to enhance photocatalytic degradation of formaldehyde under visible light

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Journal of Environmental Sciences 2024年第3期137卷 432-442页

作者： ze Wang Zhi Huang jiang Yu Xiao Shao Weidong Peng Jie Yu Yinying jiang Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Institute of New Energy and Low Carbon Technology Sichuan UniversityChengdu 610065China School of Agriculture and Environment University of Western AustraliaPerth 6907Western AustraliaAustralia Yibin Institute of Industrial Technology Sichuan UniversityYibin 644000China

Formaldehyde is a pollutant that significantly affects the indoor air ***,conventional remediation approaches can be challenging to deal with low-concentration formaldehyde in an indoor *** this study,Photocatalysts of Ag/graphitic carbon nitride(g-C_(3)N_(4))/Ni with 3D reticulated coral structure were prepared by thermal polymerization and liquid phase photo-deposition,using nickel foam(NF)as the *** demonstrated that when the Ag concentration was 3%,and the relative humidity was 60%,the Ni/Ag/g-C_(3)N_(4)showed the maximum degradation rate of formaldehyde at 90.19%under visible light irradiation,and the formaldehyde concentration after degradation was lower than the Hygienic standard stated by the Chinese *** porous structure of Ni/Ag/g-C_(3)N_(4)and the formation of Schottky junctions promoted the Adsorption efficiency and degradation of formaldehyde,while the nickel foam carrier effectively promoted the desorption of degradation ***,the degradation rate was only reduced by3.4%after 16 recycles,the three-dimensional porous structure extended the lifetime of the *** study provides a new strategy for the degradation of indoor formaldehyde at low concentrations.

关键词： Graphitic carbon nitride(g-C_(3)N_(4)) Nickel foam(NF) Ag Formaldehyde Photocatalysis

Study on a conical bearing for acceleration-sensitive equipment

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 103-128页

作者： Pang hui Xu Wen Dai Junwu jiang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China School of Civil Engineering and Transportation Beihua UniversityJilin 132013China

Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during ***,isolation strategies give less attention to acceleration-sensitive systems or ***,as the isolation layer’s displacement grows,the stiffness and frequency of traditional rolling and sliding isolation bearings increases,potentially causing self-centering and resonance *** a result,a new conical pendulum bearing has been selected for acceleration-sensitive equipment to increase self-centering capacity,and additional viscous dampers are incorporated to enhance system ***,the theoretical formula for conical pendulum bearings is supplied to analyze the device’s dynamic parameters,and shake table experiments are used to determine the proposed device’s isolation efficiency under various *** to the test results,the newly proposed devices have remarkable isolation performance in terms of minimizing both acceleration and displacement ***,a numerical model of the isolation system is provided for further research,and the accuracy is demonstrated by the aforementioned experiments.

关键词： seismic isolation acceleration-sensitive equipment the conical pendulum bearing shake table tests isolation performance,numerical model

Flexible and multifunctional triboelectric nanogenerator based on liquid metal/polyvinyl alcohol hydrogel for energy harvesting and self-powered wearable human-machine interaction

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Rare Metals 2024年第3期43卷 1186-1196页

作者： Hou-Wang Zhou Cong Zhao ze-Yu Zhao Jun-Chen jiang hui-Le Jin Shun Wang Shuang Pan Min-Yi Xu Yi-Huang Chen Hai-Ming Jin Department of Orthopaedics The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou325027China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China Dalian Key Laboratory of Marine Micro/Nano Energy and Self-Powered Systems Marine Engineering CollegeDalian Maritime UniversityDalian116026China

Hydrogel-based triboelectric nanoge nerator(TENG)has a promising applied prospect in wearable electronic ***,its low performance,poor stability,insufficient recyclability and inferior self-healing seriously hinder its ***,we report a robust route to a liquid metal(LM)/polyvinyl alcohol(PVA)hydrogel-based TENG(LP-TENG).Owing to the intrinsically liquid feature of conductive LM within the flexible PVA hydrogel,the as-prepared LP-TENG exhibited comprehensiye advantages of adaptability,biocompatibility,outstanding electrical performance,superior stability,recyclability and diverse applications,which were unattainable by traditional ***,the LP-TENG delivered appealing open circuit voltage of 250 V,short circuit current of 4μA and transferred charge of 120 nC with high stability,outperforming most advanced TENG *** LP-TENG was successfully employed for versatile applications with multifunctionality,including human motion detection,handwriting recognition,energy collection,message transmission and human-machine *** work presents significant prospects for crafting advanced materials and devices in the fields of wearable electronics,flexible skin and smart robots.

关键词： Liquid metal Hydrogel Wearable TENG Multifunctionality Human-machine interaction

The fast method and convergence analysis of the fractional magnetohydrodynamic coupled flow and heat transfer model for the generalized second-grade fluid

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Science China Mathematics 2024年第4期67卷 919-950页

作者： Xiaoqing Chi hui Zhang Xiaoyun jiang School of Mathematics and Statistics Shandong UniversityWeihai 264209China School of Mathematics Shandong UniversityJinan 250100China

In this paper,we first establish a new fractional magnetohydrodynamic(MHD)coupled flow and heat transfer model for a generalized second-grade *** coupled model consists of a fractional momentum equation and a heat conduction equation with a generalized form of Fourier *** second-order fractional backward difference formula is applied to the temporal discretization and the Legendre spectral method is used for the spatial *** fully discrete scheme is proved to be stable and convergent with an accuracy of O(τ^(2)+N-r),whereτis the time step-size and N is the polynomial *** reduce the memory requirements and computational cost,a fast method is developed,which is based on a globally uniform approximation of the trapezoidal rule for integrals on the real *** strict convergence of the numerical scheme with this fast method is *** present the results of several numerical experiments to verify the effectiveness of the proposed ***,we simulate the unsteady fractional MHD flow and heat transfer of the generalized second-grade fluid through a porous *** effects of the relevant parameters on the velocity and temperature are presented and analyzed in detail.

关键词： fractional MHD coupled flow and heat transfer model generalized second-grade fuid fast method convergence analysis numerical simulation

Neg-Entropy Mechanism as a Target for Natural Medicines

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Engineering 2024年第7期38卷 11-12页

作者： Tian-Le Gao hui-hui Guo Jian-Dong jiang Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Current strategies for drug discovery research mainly focus on molecular targets,in which structure biology plays a central role,such as the detailed mechanism of a drug-target *** principle of this approach is the presumed molecular mechanism or genetic background of the disease being *** this approach has brought progress in understanding the mode of action for some drugs,most prevalent illnesses-especially chronic diseases-are multifactorial and present with a group of symptoms,as is often the case in cardiovascular diseases,metabolic disorders,cancers,and so *** newly emerging term“multi-morbidity”(i.e.,multiple co-occurring diseases)describes a grand challenge for this strategy,and successful drug intervention for multimorbidity should be multifaceted[1].So,our research team has shifted its attention to a new direction that views the disease as a whole instead of a single-molecule abnormality,and focusing on drugs with multiple targets.

关键词： drugs diseases cardiovascular

Size effect on longitudinal MOE of microtomed wood sections and relevant theoretical explanation

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Forestry Studies in China 2009年第4期11卷 243-248页

作者： YU Yan jiang ze-hui TIAN Gen-lin Division of biomaterials International Center for Bamboo and Rattan Beijing 100102 P. R. China

It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this topic, especially based on theoretical approaches. We measured the longitudinal MOE of Chinese fir on microtomed sections ranging in thickness from 70 to 200 µm and compared these with the values of samples of normal size. The results indicate that the MOE of microtomed wood sections increases with thickness from 70 to 200 µm, but is significantly less than that of normal samples. A size effect coefficient of 2.63 is inferred based on statistical data for samples of normal size and 200 µm thick microtomed sections. Finally, an explanation based on a complete shear restraint model of cell walls and a single fiber multi-ply model is proposed for the size effect on stiffness of microtomed wood sections.

关键词： a complete shear restraint model microtomed wood sections a single fiber multi-ply model size effect