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Greatly enhanced mechanical properties of thermoelectric SnSe through microstructure engineering

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Journal of Advanced Ceramics 2023年第5期12卷 1081-1089页

作者： Chen Chen Bin-Hao Wang Chen Chen Hai-Dong Zhao Bin zhang dan Wang Tao Shen Peng-Hui Li Song Zhao Dong-Li Yu Yong-Jun Tian bo Xu Center for High Pressure Science(CHiPS) State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China School of Physical Sciences Great Bay UniversityDongguan 523000China

The outstanding thermoelectric material, SnSe, is also known for its inferior mechanical properties, which bring great inconvenience for its application in thermoelectric devices. In this work, SnSe bulks were prepared via a sequential procedure of high-pressure synthesis (HPS), ball milling, and spark plasma sintering (SPS). The produced polycrystalline samples with a unique microstructure of tightly-bound quasi-equiaxed grains exhibited excellent mechanical properties. The Vickers hardness (HV), compressive strength (σ_(c)), and bending strength (σ_(b)) reached 1.1 GPa, 300 MPa, and 90 MPa, respectively, all of which are far superior to those of ordinary polycrystalline SnSe. Furthermore, the microstructures did not deteriorate thermoelectric performance. This work demonstrated an effective procedure to prepare polycrystalline microstructure-engineered SnSe materials, which not only show advantages in device applications but also shed light on property enhancement for other layer-structured thermoelectric materials.

关键词： thermoelectric materials SnSe mechanical properties hardness

基于第四次全国中药资源普查的中国中药资源种类研究

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中国中药杂志 2024年第13期49卷 3409-3413页

作者：黄璐琦郭兰萍张小波余丽莹孙嘉惠中国中医科学院北京100700 中国中医科学院中药资源中心道地药材品质保障与资源持续利用全国重点实验室北京100700 广西壮族自治区药用植物园广西中药资源普查与研究重点实验室广西南宁530023

文章概述了第四次全国中药资源普查关于我国中药资源种类的构成及特点。第四次全国中药资源普查在野外调查和内业整理的基础上,遵循“四有原则”,即有调查记录、有凭证标本、有实物照片、有药用依据,进行中药资源种类的汇总,确保结果的... 详细信息

文章概述了第四次全国中药资源普查关于我国中药资源种类的构成及特点。第四次全国中药资源普查在野外调查和内业整理的基础上,遵循“四有原则”,即有调查记录、有凭证标本、有实物照片、有药用依据,进行中药资源种类的汇总,确保结果的科学性和准确性。根据汇总结果,我国中药资源有18817种,包括药用植物15321种、药用菌物826种、药用动物2517种、药用矿物153种。此外,第四次全国中药资源普查还分专题调查了中国特有药用植物3151种,濒危药用植物资源464种,发现新物种196种。这些最新的中药资源种类统计结果,将为中药资源保护管理和开发利用提供最新的基础数据,为中医药事业的发展提供科学指导。

关键词：中药资源普查种类特征药用植物药用菌物药用动物药用矿物

智能二维光子晶体水凝胶精准检测Hg^(2+)

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化学学报 2024年第1期82卷 9-15页

作者：史雨晴储名珠韩波马豪杰李然侯雪艳张玉琦王记江延安大学化学与化工学院、陕西省化学反应工程重点实验室、延安市新能源新功能材料重点实验室陕西延安716000

结合二维光子晶体的德拜衍射效应和水凝胶的体积相转变特性,开发了一种智能二维光子晶体水凝胶,用于精准检测Hg^(2+).采用“三明治”法制备了聚苯乙烯二维光子晶体阵列嵌入的聚(丙烯酰胺-烯丙基硫脲)水凝胶.水凝胶链上功能基团的N、O、... 详细信息

结合二维光子晶体的德拜衍射效应和水凝胶的体积相转变特性,开发了一种智能二维光子晶体水凝胶,用于精准检测Hg^(2+).采用“三明治”法制备了聚苯乙烯二维光子晶体阵列嵌入的聚(丙烯酰胺-烯丙基硫脲)水凝胶.水凝胶链上功能基团的N、O、S等原子与Hg^(2+)选择性配位,缩短了水凝胶链之间的距离,增加了水凝胶的交联密度,使其收缩,导致二维光子晶体的聚苯乙烯微球间距缩小,德拜衍射环直径变大.通过监测二维光子晶体水凝胶响应前后的德拜衍射环直径,获知微球间距变化,实现了高灵敏、高选择性、快速、可逆检测Hg^(2+).线性检测范围为10~100nmol/L和25~200μmol/L,最低检测限3.32nmol/L.所制智能二维光子晶体水凝胶已成功应用于化妆品及水样中Hg^(2+)的检测.该方法测试简单,只需激光笔和刻度尺,无需精密的仪器设备,可实现便携式检测,为金属离子检测提供了新思路.

关键词：二维光子晶体德拜衍射效应智能水凝胶体积相转变汞离子

循环动载边界下三维粗糙节理面剪切力学响应研究

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岩石力学与工程学报 2024年第5期43卷 1176-1189页

作者：尹乾何满潮靖洪文王琦祁生文吴疆宇孟波张强朱淳吴赛赛中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116 中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室北京100083 中国科学院地质与地球物理研究所北京100029

开展正弦波式循环法向动载–循环剪切位移叠加作用下三维粗糙节理面剪切试验,探讨初始法向静载(Fs)、法向动载振幅(Fa)、法向动载频率(fv)及循环剪切次数(N)对节理面剪切特性的影响。随着Fs与Fa的增加,节理面法向荷载变化范围逐渐增大,... 详细信息

开展正弦波式循环法向动载–循环剪切位移叠加作用下三维粗糙节理面剪切试验,探讨初始法向静载(Fs)、法向动载振幅(Fa)、法向动载频率(fv)及循环剪切次数(N)对节理面剪切特性的影响。随着Fs与Fa的增加,节理面法向荷载变化范围逐渐增大,一个剪切位移周期内剪切荷载呈现波动增加→波动减小→波动增加趋势;稳定状态下峰值剪切荷载随着Fs与Fa的增加分别增大4.90倍与65.12%,节理面抗剪能力逐渐增强,而随着fv的增加,节理表面损伤渐进累积导致峰值剪切荷载逐渐减小,且出现的时刻逐渐前移,稳定状态峰值剪切荷载减小17.49%。一个剪切位移周期内节理面法向位移呈现波动增加→波动减小→二次增加→二次减小的趋势,当节理面远离初始位置剪切时,凸起体持续“爬坡效应”导致法向位移逐渐增大;节理面法向位移–法向荷载呈现明显负相关,且最大法向位移滞后于最大剪切位移1/4法向荷载周期;随着N的增加,节理面持续磨损劣化导致最大法向位移呈指数函数减小趋势;最大法向位移随着Fs,Fa及fv的增加分别呈现逐渐减小、逐渐增加及先增后减的特征。剪切后节理表面粗糙度系数随着Fs,Fa与fv的增加,呈现的变化规律分别为减小了57.79%,43.26%以及以1 Hz为拐点先增加后减小的趋势。

关键词：岩石力学粗糙节理面循环剪切法向动载法向位移表面磨损

Low-frequency transcranial magnetic stimulation is beneficial for enhancing synaptic plasticity in the aging brain

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Neural Regeneration Research 2015年第6期10卷 916-924页

作者： Zhan-chi zhang Feng Luan Chun-yan Xie dan-dan Geng Yan-yong Wang Jun Ma Department of Human Anatomy Hebei Medical University Department of Otorhinolaryngology Third Hospital of Hebei Medical University Second Surgical Department Qinghe Public Hospital of Hebei Province Department of Neurology First Hospital of Hebei Medical University Hebei Key Laboratory for Brain Aging and Cognitive Neuroscience

In the aging brain, cognitive function gradually dedines and causes a progressive reduction in the structural and functional plasticity of the hippocampus. Transcranial magnetic stimulation is an emerging and novel neurological and psychiatric tool used to investigate the neurobiology of cognitive function. Recent studies have demonstrated that low-frequency transcranial magnetic stimulation （〈1 Hz） ameliorates synaptic plasticity and spatial cognitive deficits in learning-impaired mice. However, the mechanisms by which this treatment improves these deficits during normal aging are still unknown. Therefore, the current study investigated the effects of transcranial magnetic stimulation on the brain-derived neurotrophic factor signal pathway, synaptic protein markers, and spatial memory behavior in the hippocampus of normal aged mice. The study also investigated the downstream regulator, Fyn kinase, and the downstream effectors, synaptophysin and growth-associated protein 43 （both synaptic markers）, to determine the possible mechanisms by which transcranial magnetic stimulation regulates cognitive capacity. Transcranial magnetic stimulation with low intensity （110% average resting motor threshold intensity, 1 Hz） increased mRNA and protein levels of brain-derived neurotrophic factor, tropomyosin receptor kinase B, and Fyn in the hippocampus of aged mice. The treatment also upregulated the mRNA and protein expression of synaptophysin and growth-associated protein 43 in the hippocampus of these mice. In conclusion, brain-derived neurotrophic factor signaling may play an important role in sustaining and regulating structural synaptic plasticity induced by transcranial magnetic stimulation in the hippocampus of aging mice, and Fyn may be critical during this regulation. These responses may change the structural plasticity of the aging hippocampus, thereby improving cognitive function.

关键词： neural regeneration non-invasive brain stimulation transcranial magnetic stimulation neurotrophic factor brain-derived neurotrophic factor neuroplasticity hippocampus aging cognitive function

污水处理过程逸散的生物气溶胶抗生素抗性分析

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环境科学 2024年第8期45卷 4512-4519页

作者：杨唐王旭一隋心惠晓亮王振兴姜波张展鹏李新龙青岛理工大学环境与市政工程学院青岛266520 中建八局发展建设有限公司青岛266061

为探究污水处理厂生物气溶胶负载抗生素抗性基因(ARGs)和抗生素抗性致病菌(PARB)的赋存及来源.利用宏基因组测序与组装技术对山东省某污水处理厂生物气溶胶及污水样本的抗生素抗性基因组进行检测.结果表明,相比于上风向,污水处理厂和下... 详细信息

为探究污水处理厂生物气溶胶负载抗生素抗性基因(ARGs)和抗生素抗性致病菌(PARB)的赋存及来源.利用宏基因组测序与组装技术对山东省某污水处理厂生物气溶胶及污水样本的抗生素抗性基因组进行检测.结果表明,相比于上风向,污水处理厂和下风向生物气溶胶中具有更多的ARGs亚型种类数和更高丰度的PARB.污水处理厂生物气溶胶中主导的ARGs主型和亚型分别为多药类ARGs和macB.37种PARB携带至少两种及以上的ARGs主型,表现出多重耐药性.对于细格栅、好氧池和污泥脱水间生物气溶胶样本,污水是ARGs和PARB最主要的来源.共检测到铜绿假单胞菌(Pseudomonas aeruginosa)和大肠埃希氏菌(Escherichia coli)等32种PARB在至少1个污水处理单元极易气溶胶化.研究将为污水处理厂生物气溶胶抗生素抗性污染风险评估及健康保障提供理论支持.

关键词：污水处理厂生物气溶胶抗生素抗性基因(ARGs) 抗生素抗性致病菌(PAPB) 来源

Breed identification using breed‑informative SNPs and machine learning based on whole genome sequence data and SNP chip data

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畜牧与生物技术杂志:英文版 2023年第5期14卷 1941-1953页

作者： Changheng Zhao dan Wang Jun Teng Cheng Yang Xinyi zhang Xianming Wei Qin zhang Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention College of Animal Science and Veterinary MedicineShandong Agricultural UniversityTai’an 271018China

Background Breed identification is useful in a variety of biological *** identification usually involves two stages,i.e.,detection of breed-informative SNPs and breed *** both stages,there are several methods ***,what is the optimal combination of these methods remain *** this study,using the whole genome sequence data available for 13 cattle breeds from Run 8 of the 1,000 Bull Genomes Project,we compared the combinations of three methods(Delta,FST,and In)for breed-informative SNP detection and five machine learning methods(KNN,SVM,RF,NB,and ANN)for breed assignment with respect to different reference population sizes and difference numbers of most breed-informative *** addition,we evaluated the accuracy of breed identification using SNP chip data of different *** We found that all combinations performed quite well with identification accuracies over 95%in all ***,there was no combination which performed the best and robust across all *** proposed to inte-grate the three breed-informative detection methods,named DFI,and integrate the three machine learning methods,KNN,SVM,and RF,named *** found that the combination of these two integrated methods outperformed the other combinations with accuracies over 99%in most cases and was very robust in all *** accuracies from using SNP chip data were only slightly lower than that from using sequence data in most *** The current study showed that the combination of DFI and KSR was the optimal *** sequence data resulted in higher accuracies than using chip data in most ***,the differences were gener-ally *** view of the cost of genotyping,using chip data is also a good option for breed identification.

关键词： Breed identification Breed-informative SNPs Genomic breed composition Machine learning Whole genome sequence data

Performance analysis of a single-stage scroll compressor used in a drying heat pump over a wide condensing temperature range(30–80°C)

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Science China(Technological Sciences) 2014年第11期57卷 2131-2137页

作者： WEI Juan YANG LuWei zhang ZhenTao LIN XueJun zhang Chong LI bo Technical Institute of Physics and Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

This study presents the performance of a new single-stage scroll compressor used for the heat pump drying of thermally sensitive materials over a wide temperature range. The performance of the new compressor was predicted by an ARI standard 540 map-based compressor model and verified by a semi-open drying heat pump system constructed for this purpose. A comparison of the experimental data with the predicted data proved that the new scroll compressor used in the drying heat pump works well, can supply a wide range of condensing temperatures （30--80℃）（without auxiliary heating）, and has a minimum coeffi- cient of performance （COP） above 2.0, even in the worst condition.

关键词： drying scroll compressor performance wide temperature range

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公立医院临床研究协调员工作现状与分析

中国医药导报 2024年第2期21卷 189-192,F0003页

作者：张云颜波周爽钱瑾瑜上海市胸科医院上海交通大学医学院附属胸科医院临床研究中心上海200030 上海市胸科医院上海交通大学医学院附属胸科医院放疗科上海200030

目的了解临床研究协调员(CRC)工作现状,为促进CRC职业健康成长,建立合理的CRC管理体系。方法在2023年2月至3月,通过问卷调查上海市某公立医院CRC基本信息、工作现状及工作医院等方面内容,采用单因素和多因素分析方法,探讨CRC职业发展的... 详细信息

目的了解临床研究协调员(CRC)工作现状,为促进CRC职业健康成长,建立合理的CRC管理体系。方法在2023年2月至3月,通过问卷调查上海市某公立医院CRC基本信息、工作现状及工作医院等方面内容,采用单因素和多因素分析方法,探讨CRC职业发展的影响因素。结果本研究共发放215份问卷,最终收集207份有效问卷,问卷回收率为96.82%,分析结果显示年龄、薪资与能力匹配度、和人打交道难度、家人支持力度、医院培训频次对职业发展意愿有影响(P<0.05);低年龄、薪资与能力匹配度高、和人打交道难度低的CRC将其作为职业发展的意愿更高(P<0.05)。结论CRC是临床试验中的重要组成部分,可以通过加强CRC培训及考核机制,建立有效的沟通渠道,完善激励政策,提高CRC薪酬水平等方面,提升职业认同感和归属感,从而保持CRC队伍的稳定性。

关键词：临床研究协调员工作现状药物临床试验工作意愿