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结合BP神经网络和高阶矩法的渡槽侧墙抗弯时变可靠度分析

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中国农村水利水电 2024年第1期 16-24页

作者：张龙文周伦秀刘倩湖南农业大学水利与土木工程学院湖南长沙410128 湖南农业大学农业高效节水与水利数字建造湖南省普通高等学校重点实验室湖南长沙410128

基于BP神经网络与高阶矩法,结合实测数据,提出了钢筋混凝土渡槽侧墙抗弯时变可靠度分析方法。为评估钢筋锈蚀影响下的渡槽侧墙抗弯时变可靠度,考虑混凝土结构中钢筋有效截面面积损失效应,导出渡槽侧墙承载能力极限状态下的抗弯时变功能... 详细信息

基于BP神经网络与高阶矩法,结合实测数据,提出了钢筋混凝土渡槽侧墙抗弯时变可靠度分析方法。为评估钢筋锈蚀影响下的渡槽侧墙抗弯时变可靠度,考虑混凝土结构中钢筋有效截面面积损失效应,导出渡槽侧墙承载能力极限状态下的抗弯时变功能函数;接着,结合钢筋锈蚀实测数据和BP神经网络原理设计钢筋锈蚀速率预测模型,通过半球形点蚀模型建立混凝土结构中钢筋有效截面面积计算公式;在此基础上,引入点估计-高阶矩可靠度理论发展渡槽结构时变可靠度分析方法,最后将提出的方法应用于某实际渡槽侧墙抗弯时变可靠度分析。结果表明:较之以往的8个实用经验模型,本文所建BP神经网络预测模型可以更准确、综合、简便、快速地预测混凝土结构中的钢筋锈蚀速率;通过与蒙特卡洛模拟法对比验证,本文方法求解时变可靠指标高效准确,可为渡槽时变可靠度评估预测提供一条有效的途径。

关键词：渡槽时变可靠度钢筋锈蚀 BP神经网络高阶矩

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益肾健脾利水泄浊法治疗糖尿病肾病疗效分析

湖北中医药大学学报 2024年第4期26卷 36-39页

作者：王秀莹赵长松张文龙河北省唐山市中医医院河北唐山063099

目的观察益肾健脾利水泄浊法在糖尿病肾病(DN)患者中的应用效果。方法将我院120例DN患者随机分为观察组与对照组各60例。两组均行基础治疗后,对照组使用益气滋阴活血化瘀法治疗,观察组使用益肾健脾利水泄浊法治疗。比较两组临床疗效,治... 详细信息

目的观察益肾健脾利水泄浊法在糖尿病肾病(DN)患者中的应用效果。方法将我院120例DN患者随机分为观察组与对照组各60例。两组均行基础治疗后,对照组使用益气滋阴活血化瘀法治疗,观察组使用益肾健脾利水泄浊法治疗。比较两组临床疗效,治疗前后肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)、白细胞介素-6(IL-6)等炎症指标,空腹血糖(FPG)、糖化血红蛋白(HbA1c)、餐后2h血糖(2hPG)等血糖指标,血肌酐(SCr)、胱抑素C(CysC)、尿白蛋白(mAlb)、尿素氮(BUN)、肾小球滤过率(eGFR)等肾功能指标,超氧化物歧化酶(SOD)、丙二醛(MDA)、总抗氧化能力(T-AOC)等氧化反应指标,CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)等免疫功能指标;开展肠道菌群监测,寻找特征差异菌群。结果治疗后观察组总有效率显著高于对照组(P<0.05);两组TNF-α、CRP、IL-6、FPG、HbA1c、2hPG、mAlb、BUN、SCr、CysC、MDA、CD8^(+)水平均低于治疗前(P<0.05),观察组上述指标均低于对照组(P<0.05);两组双歧杆菌、大肠杆菌、乳酸杆菌、拟杆菌、肠球菌、B/E值、eGFR、SOD、T-AOC、CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均高于治疗前(P<0.05),观察组上述指标均高于对照组(P<0.05)。结论益肾健脾利水泄浊法治疗糖尿病肾病疗效较好,能有效改善病情,改善血糖水平及肾功能,其作用机制在于调节肠道菌群,改善炎症、氧化应激、免疫。

关键词：糖尿病肾病益肾健脾利水泄浊法益气滋阴活血化瘀法

Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures

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Nano-Micro Letters 2024年第4期16卷 305-349页

作者： Xianfu zhang long zhang Xinyuan Jia wen Song Yongchang Liu School of Materials Science and Engineering University of Science and Technology Beijing30 College RoadBeijing 100083People’s Republic of China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China

Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented.

关键词： Aqueous zinc metal batteries Zinc anodes High zinc utilization Depth of discharge Anode-free structures

光谱法、量热法以及分子对接研究酸枣仁皂苷A与中心蛋白的作用

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食品安全质量检测学报 2024年第3期15卷 286-292页

作者：张文龙胡颖媛郭丽丽裴科山西中医药大学中药与食品工程学院晋中030619

目的研究酸枣仁皂苷A(jujuboside A,JuA)与八肋游仆虫中心蛋白(Euplotes octocarinatus centrin,EoCen)的相互作用。方法采用圆二色光谱(circular dichroism spectroscopy,CD)以及三维荧光光谱研究EoCen的构象变化;采用稳态荧光光谱与等温滴定量热法(isothermal titration calorimetry,ITC)研究JuA与EoCen作用的机制;分子对接技术模拟JuA与EoCen的结合位点。结果JuA以摩尔比1:1结合于EoCen的C端(二者反应的结合常数约为10^(5)L/mol),由ITC拟合结果可知,JuA与EoCen复合物的形成是放热的过程,熵变对自由能的贡献较小,主要由焓变驱动。EoCen与JuA结合后,构象发生变化,α-螺旋含量减少,酪氨酸残基的微环境变化,EoCen的C端不再结合蜂毒素。结论JuA主要通过范德华力与EoCen结合,从而改变EoCen的构象,抑制其与靶蛋白的结合。

关键词：八肋游仆虫中心蛋白酸枣仁皂苷A 圆二色光谱三维荧光光谱稳态荧光光谱等温滴定量热法分子对接技术

The Effect of Blending Ratio on the Structure and Properties of the PPR/PS In situ Fiber Reinforced System Prepared by Multi-Flow Vibration Injection Molding

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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-long Hu Jun-wen zhang Qiang Fu Jie zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan Xiang wen-long zhang He-Ting Li Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

Close-packed layer spacing as a practical guideline for structure symmetry manipulation of IV-VI/I-V-VI_(2) thermoelectrics

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InfoMat 2024年第2期6卷 99-106页

作者： Tao Jin long Yang Xinyue zhang wen Li Yanzhong Pei Interdisciplinary Materials Research Center School of Materials Science and EngineeringTongji UniversityShanghaithe People's Republic of China

The crystal-structure symmetry in real space can be inherited in the reciprocal space,making high-symmetry materials the top candidates for thermoelectrics due to their potential for significant electronic band degeneracy.A practical indicator that can quantitatively describe structural changes would help facilitate the advanced thermoelectric material *** face-centered cubic structures,the spatial environment of the same crystallographic plane family is isotropic,such that the distances between the close-packed layers can be derived from the atomic distances within the *** by this,the relationship between inter-and intra-layer geometric information can be used to compare crystal structures with their desired cubic *** close-packed layer spacing was found to be a practical guideline of crystal structure symmetry in IV-VI chalcogenides and I-V-VI_(2) ternary semiconductors,both of which are historically important *** continuous structural evolution toward high symmetry can be described by the layer spacing when temperature or/and composition change,which is demonstrated by a series of pristine and alloyed thermoelectric materials in this *** layerspacing-based guideline provides a quantitative pathway for manipulating crystal structures to improve the electrical and thermal properties of thermoelectric materials.

关键词： phase transition structure manipulation thermoelectric materials x-ray diffraction

A highly selective electrochemical impedimetric sensor for imidacloprid determination based on WO_(3)/MoS_(2)nanosheets/molecularly imprinted polymer composite

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Rare Metals 2024年第3期43卷 1309-1315页

作者： long-Hua Ding Ya-wen Wang Qiu-wen Li Li-Li zhang Ai-Zhu Wang Institute for Advanced Interdisciplinary Research School of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China HCA Florida Healthcare Westside/Northwest Hospital Internal Medicine PlantationFL33324USA

In this study,an electrochemical impedimetric sensor was established for imidacloprid(IMI)detection based on WO_(3)/MoS_(2)and molecular imprinted polymer(MIP)*** layer was prepared on electrode surface by electropolymerization of o-phenylenediamine(o-PD)in the presence of IMI template,which ensured the specific rec-ognization toward IMI.

关键词： electrochemical polymer polymerization

Human umbilical cord mesenchymal stem cells derivedexosomes on VEGF-A in hypoxic-induced mice retinal astrocytes and mice model of retinopathy of prematurity

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1238-1247页

作者： Xiao-Tian zhang Bo-wen Zhao Yuan-long zhang Song Chen Tianjin Eye Hospital Tianjin 300020China Tianjin Key Lab of Ophthalmology and Visual Science Tianjin 300020China

AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A(VEGF-A)and to observe the therapeutic effect on the mouse model of retinopathy of prematurity(ROP).METHODS:Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia *** assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR)and Western blot were used to detect related *** mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were *** last,the efficacy of exosomes of UCMSCs in a mouse ROP model was ***6 was used to comprehensively process data ***:The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient *** oxygen species(ROS)and hypoxia inducible factor-1α(HIF-1α)of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased,and the ROP cell model was established after 6h of *** secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α,the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration *** with the ROP cell model group,the expression of phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signal pathway related factors in the hUCMSCs exocrine group is significantly *** intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1αin ROP model *** staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs ***:In a hypoxia induced

关键词： human umbilical cord mesenchymal stem cells retinal astrocytes retinopathy of prematurity vascular endothelial growth factor hypoxia inducible factor