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熔体旋甩工艺对Mg_(2)(Si_(0.4)Sn_(0.6))Sb_(0.015)固溶体微结构和热电性能的影响研究

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材料导报 2024年第12期38卷 27-31页

作者：刘洪亮郭志迎袁晓峰朱尊伟高倩倩张忻安阳工学院材料科学与工程学院河南安阳455000 北京工业大学新型功能材料教育部重点实验室北京100124

Mg_(2)(Si,Sn)基材料是环境友好的热电材料,具有较好的应用前景。本工作采用熔体旋甩(MS)结合放电等离子烧结(SPS)技术(MS+SPS)制备了单相的Mg_(2)(Si_(0.4)Sn_(0.6))Sb0.015固溶体,通过将机械合金化(MA)与放电等离子烧结(SPS)技术(MA+S... 详细信息

Mg_(2)(Si,Sn)基材料是环境友好的热电材料,具有较好的应用前景。本工作采用熔体旋甩(MS)结合放电等离子烧结(SPS)技术(MS+SPS)制备了单相的Mg_(2)(Si_(0.4)Sn_(0.6))Sb0.015固溶体,通过将机械合金化(MA)与放电等离子烧结(SPS)技术(MA+SPS)结合制备的相同样品进行对比,研究MS工艺对样品微结构以及热电性能的影响。结果表明,MS得到的固溶体薄带主要由200~500 nm的小颗粒组成,将薄带研磨制粉经SPS烧结后得到的致密块体具有明显细化的晶粒和分布均匀的共格纳米析出相。与MA+SPS工艺制备的样品相比,MS+SPS制备的固溶体的迁移率明显降低,在一定温度范围内,电阻率略有升高,Seebeck系数显著增加,热导率和晶格热导率显著降低。MS+SPS制备的Mg_(2)(Si_(0.4)Sn_(0.6))Sb0.015固溶体热电性能明显提高,在643 K时其最大ZT值达到1.30。

关键词： Mg_(2)Si_(0.4)Sn_(0.6)固溶体熔体旋甩(MS) 纳米析出相热电性能

n型Bi_(2)Te_(3-x)Se_(x)纳米结构材料的制备及热电性能

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金属功能材料 2024年第3期31卷 36-42页

作者：郭志迎刘洪亮王朋安阳工学院化学与环境工程学院河南安阳455000 安阳工学院材料科学与工程学院河南安阳455000

采用蒸发冷凝法将块体Bi、Te及Se制备成单质纳米粉末,将单质纳米粉末按照Bi_(2)Te_(3)-xSex化学计量后充分混合后进行机械合金化。将合金化的粉末采用微波烧结技术烧结制得具有纳米结构的块体材料,对其微结构和热电性能进行了表征分析... 详细信息

采用蒸发冷凝法将块体Bi、Te及Se制备成单质纳米粉末,将单质纳米粉末按照Bi_(2)Te_(3)-xSex化学计量后充分混合后进行机械合金化。将合金化的粉末采用微波烧结技术烧结制得具有纳米结构的块体材料,对其微结构和热电性能进行了表征分析。研究表明,烧结块体由单一物相组成,材料内部具有层状微结构并且存在大量晶粒尺度为50~100 nm的细小晶粒构成的纳米结构。随着Se含量的增加,烧结块体的电输运特性由半导体转变为金属,纳米结构的形成有效降低了热导率,有利于材料热电性能的提升,当x=0.20时,Bi_(2)Te_(2.80)Se_(0.20)样品在423K附近获得最大的ZT值为0.85。

关键词：碲化铋热电材料掺杂纳米结构热电性能

Tensile Properties with or without Heat Dispersion of Automotive Needlepunched Carpets Made up of Two Layers of Different Materials

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 625-631页

作者： ZHANG Yunqing guo zhiying DONG Xianghuai LI Dequn National Die and Mold CAD Engineering Research Center Shanghai Jiaotong UniversityShanghai 200030China

Tensile properties of automotive needlepunched carpets made up of two layers of different materials （a fabric layer and a foam layer） in their thermoforming temperatures ranges with or without heat dispersion were discussed. Effects of forming temperature, extensile speed and fiber orientation on the tensile properties were studied based on an orthogonal experiment design. The experimental results show that automotive carpets are rate-dependent anisotropic materials and more strongly depend on forming temperature than the extensile speed and fiber orientation. Furthermore, contributions of the fabric layer and the foam layer to the overall tensile performance were investigated by comparing the tensile results of single fabric layer with those of the overall carpet. Both the fabric layer and the foam layer show positive effects on the overall tensile strength which is the combination of the two layers＇ tensile strength and independent of temperature, extensile speed and fiber orientation On the other hand, their influences on the overall deformation are relatively complicated.

关键词： automotive needlepunched carpet mechanical behavior formability

Chronosequencing methanogenic archaea in ancient Longji rice Terraces in China

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Science Bulletin 2017年第12期62卷 879-887页

作者： Youzhi Feng Jan Dolfing zhiying guo Jianwei Zhang Ganlin Zhang Shijie Li Xiangui Lin State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China School of Civil Engineering and Geosciences Newcastle UniversityNewcastle upon Tyne NEt 7RUUK State Key Laboratory of Environmentul Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China

Chronosequences of ancient rice terraces serve as an invaluable archive for reconstructions of historical human-environment interactions. Presently, however, these reconstructions are based on traditional soil physico-chemical properties. The microorganisms in palaeosols have been unexplored. We hypothesized that microbial information can be used as an additional proxy to complement and consolidate archaeological interpretations. To test this hypothesis, the palaeoenvironmental methanogenic archaeal DNA in Longji Terraces, one of the famous ancient terraces in China, dating back to the late Yuan Dynasty(CE1361–1406), was chronosequenced by high-throughput sequencing. It was found that the methanogenic archaeal abundance, diversity and community composition were closely associated with the 630 years of rice cultivation and in line with changes in multi-proxy data. Particularly, the centennial-and decadalscale influences of known historical events, including social turbulences(The Taiping Rebellion, CE1850–1865), palaeoclimate changes(the Little Ice Age) and recorded natural disasters(earthquakes and inundation), on ancient agricultural society were clearly echoed in the microbial archives as variations in alpha and beta diversity. This striking correlation suggests that the microorganisms archived in palaeosols can be quantitatively and qualitatively analyzed to provide an additional proxy, and palaeo-microbial information could be routinely incorporated in the toolkit for archaeological interpretation.

关键词： Ancient paddy soilAnthropogenic activitiesPalaeosol microorganismsLongji Terraces

Modified corn-core powder for enhancing sludge dewaterability:Synthesis,characterization and sludge dewatering performance

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Chinese Journal of Chemical Engineering 2021年第4期34卷 368-377页

作者： zhiying guo Liping Ma I Quxiu Dai Xinbo Yang Ran Ao Jie Yang Jing Yang Wengang Li Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China Yunnan Tianlang Energy Saving&Environmental Protection Group Co.Ltd Kunming 650300China College of Resources and Environment Chengdu University of Information TechnologyChengdu 610225China School of Environmental and Municipal Engineering Xi'an University of Architecture and TechnologyXi'an 710000China

The high water content of sludge has always posed significant challenges for its *** flocculants,which are widely used in sewage treatment plants,can cause secondary pollution during their production and ***,natural polymer flocculants made of natural materials have received increased research attention ***,an agricultural waste,was modified through alkalization with sodium hydroxide(NaOH)and etherification with cetyltrimethylammonium bromide(CTMAB)in this *** L16(45)orthogonal array was used to study the modification *** moisture content(MC)of treated sludge was reduced by approximately 37%with the addition of modified corncore powder(MCCP),which was synthesized under optimal *** addition,changes in the functional groups of the material before and after modification were determined by *** analysis indicated that MCCP was steady at room temperature,moreover,BET analysis showed that MCCP had greater surface *** microstructures of material before and after modification were examined by scanning electron microscopy,revealing that MCCP had a flakeshaped structure and had an increased area of contact area with sludge *** is a dehydrating agent that can enhance sludge dewaterability through charge neutralization and reagglomeration and provide superior economic benefits.

关键词： Municipal sludge Corn-core powder Pollution Polymers Waste treatment

哲学思维在“病理生理学”教学中的渗透与运用

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医学教育研究与实践 2024年第4期32卷 475-480页

作者：孙芳王友王建礼葛洪刚郭志英济宁医学院基础医学院山东济宁272067 济宁医学院马克思主义学院山东济宁272067

医学和哲学有着密不可分的联系,病理生理学是医学生的主干基础课程,教师在课程教学中传授病理生理学基本知识和技能的同时,应善于发现和挖掘病理生理学课程中蕴含的哲学思维,并将其运用在病理生理学教学实践中,可帮助学生运用哲学思想... 详细信息

医学和哲学有着密不可分的联系,病理生理学是医学生的主干基础课程,教师在课程教学中传授病理生理学基本知识和技能的同时,应善于发现和挖掘病理生理学课程中蕴含的哲学思维,并将其运用在病理生理学教学实践中,可帮助学生运用哲学思想分析、学习病理生理学内容,培养学生科学学习的能力,提升分析和解决实际临床问题的能力。通过具体例证论述病理生理学教学过程中渗透的哲学思维,运用联系观、发展观、矛盾观等哲学的观点,以及科学的方法论,阐释病理生理学教学中哲学思维的渗透,并以“脱水”为例,介绍了哲学思维在病理生理学教学中的具体运用,以期抛砖引玉,为病理生理学的“教”与“学”提供参考借鉴。

关键词：病理生理学哲学思维唯物辩证法教学实践

初诊帕金森病患者小幻觉患病率和相关危险因素分析

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临床神经病学杂志 2024年第2期37卷 86-90页

作者：曹以婷刘卫国郭志颖尹奎英吴钧郑慧芬南京医科大学附属脑科医院神经内科 210029 南京医科大学附属脑科医院检验科 210029 中国电子科技集团公司第十四研究所人脑机实验室南京医科大学附属老年医院神经内科

目的调查初诊未服药的帕金森病(PD)患者中小幻觉(MH)的患病率和相关危险因素。方法纳入2018年11月至2022年12月南京医科大学附属脑科医院PD专病门诊收治的274例初诊未服药PD患者,根据统一PD评定量表第一部分(UPDRSⅠ)第2项评分筛选出MH... 详细信息

目的调查初诊未服药的帕金森病(PD)患者中小幻觉(MH)的患病率和相关危险因素。方法纳入2018年11月至2022年12月南京医科大学附属脑科医院PD专病门诊收治的274例初诊未服药PD患者,根据统一PD评定量表第一部分(UPDRSⅠ)第2项评分筛选出MH的PD患者(MH组,评分≥2分),并在非MH的PD患者(NMH组,评分0分)中筛选年龄、性别、教育程度、病程相匹配的患者。采用合适的量表评估患者认知功能、抑郁症状、焦虑症状、睡眠质量、非运动症状、快速眼动期睡眠障碍(RBD)症状、日常生活活动、运动功能、病情严重程度,比较两组间的差异,并使用单因素和多因素前进法Logistic回归分析PD患者发生MH的相关危险因素。结果274例初诊PD患者中共11例(4.01%)出现MH。与NMH组(22例)相比,MH组的汉密尔顿抑郁量表(HAMD)评分、汉密尔顿焦虑量表(HAMA)评分、PD非运动症状问卷量表(PDNMS)评分、RBD评分显著升高(均P<0.05)。单因素Logistic回归分析显示,HAMD评分高、HAMA评分高、PDNMS评分高、RBD评分高是PD患者发生MH的危险因素(均P<0.05)。进一步进行多因素Logistic回归分析显示,HAMD评分高(OR=1.182,95%CI:1.004~1.392,P=0.045)、RBD评分高(OR=4.448,95%CI:1.066~18.557,P=0.041)是PD患者发生MH的独立危险因素。结论初诊未服药的PD患者出现MH的概率较低,且抑郁、RBD为PD患者发生MH的独立危险因素,应重视该类患者的筛查并采取早期的干预措施。

关键词：帕金森病初诊小幻觉危险因素

The Relationship Between the Atmospheric Environment and Road Traffic Fatalities — Shandong Province, China, 2012–2021

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China CDC weekly 2024年第13期6卷 267-271页

作者： Tao Wang Jie Chu zhiying Yao Li Yang Zilong Lu Ge Tian Xiaolei guo Cunxian Jia Department of Epidemiology School of Public HealthCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department for Chronic and Non-Communicable Disease Control and Prevention Shandong Center for Disease Control and PreventionJinanShandong ProvinceChina

Introduction:This study aims to analyze the potential impact of the meteorological environment and air pollutants on road traffic ***:Road traffic fatality data in Shandong Province from 2012 to 2021 were obtained from the Population Death Information Registration Management *** and air pollutant data for the same period were collected from the *** Oceanic and Atmospheric Administration and the Ecological Environment Monitoring Center of Shandong Province,***’s correlation and ridge regression were used to analyze the impact of the meteorological environment and air pollutants on road traffic ***:From 2012 to 2021,there were 163,863 road traffic fatality *** results of the ridge regression analysis showed that the daily average temperature was negatively correlated with total fatalities and passengers and positively correlated with pedestrians,nonmotorized drivers,and motorized *** daily minimum temperature was negatively correlated with total fatalities and positively correlated with motorized *** daily maximum temperature was positively correlated with both pedestrian and nonmotorized *** daily accumulated precipitation was negatively correlated with *** duration was positively correlated with both nonmotorized and motorized *** particulate matter(PM_(10))and nitrogen dioxide(NO_(2))were positively correlated with total fatalities,pedestrians,and nonmotorized *** dioxide(SO_(2))was positively correlated with total fatalities but negatively correlated with nonmotorized drivers,passengers,and motorized ***:Atmospheric factors associated with the occurrence of road traffic fatalities include air temperature,daily accumulated precipitation,sunshine duration,and air pollutants such as PM_(10),NO_(2),and SO_(2).

关键词： Ecological dioxide sunshine

Increasing root-lower characteristics improves drought tolerance in cotton cultivars at the seedling stage

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Journal of Integrative Agriculture 2024年第7期23卷 2242-2254页

作者： Congcong guo Hongchun Sun Xiaoyuan Bao Lingxiao Zhu Yongjiang Zhang Ke Zhang Anchang Li zhiying Bai Liantao Liu Cundong Li State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Crop Growth Regulation of Hebei Province/College of Agronomy Hebei Agricultural UniversityBaoding 071001China

Drought is an important abiotic stress factor in cotton *** root system architecture(RSA)of cotton shows high plasticity which can alleviate drought-related stress under drought stress(DS)conditions;however,this alleviation is cultivar ***,this study estimated the genetic variability of RSA in cotton under *** the paper-based growth system,we assessed the RSA variability in 80 cotton cultivars at the seedling stage,with 0 and10%polyethylene glycol 6000(PEG6000)as the control(CK)and DS treatment,*** analysis of 23 aboveground and root traits in the 80 cotton cultivars revealed different responses to *** the 10th day after DS treatment,the degree of variation in the RSA traits under DS(5–55%)was greater than that of CK(5–49%).The 80 cultivars were divided into drought-tolerant cultivars(group 1),intermediate drought-tolerant cultivars(group 2),and drought-sensitive cultivars(group 3)based on their comprehensive evaluation values of drought *** DS,the root lengthlower,root area-lower,root volume-lower,and root length density-lower were significantly reduced by 63,71,76,and 4%in the drought-sensitive cultivars compared to ***,the drought-tolerant cultivars maintained their root lengthlower,root area-lower,root volume-lower,and root length density–lower *** to CK,the root diameter(0–2 mm)-lower increased by 21%in group 1 but decreased by 3 and 64%in groups 2 and 3,respectively,under ***,the drought-tolerant cultivars displayed a plastic response under DS that was characterized by an increase in the root-lower *** resistance was positively correlated with the root area-lower and root length ***,the RSA of the different cotton cultivars varied greatly under ***,important root traits,such as the root-lower traits,provide great insights for exploring whether drought-tolerant cotton cultivars can effectively withstand adverse environment

关键词： cotton root system architecture drought stress cultivars variability root-lower