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Anomalous temperature dependent photoluminescence properties of CdS_xSe_(1-x) quantum dots

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1842-1846页

作者： YU DongQi chen xi zhang HeQiu hu LiZhong SUN jingChang QIAO ShuangShuang SUN KaiTong zhu Jinxia School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029China School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024China

CdSxSe1-x quantum dots were fabricated by a simple spin-coating heat volatilization method on InP *** dependent photoluminescence of CdSxSe1-x quantum dots was carried out in a range of 10-300 *** integrated photoluminescence intensity revealed an anomalous behavior with increasing temperature in the range of 180-200 *** band gap energy showed a redshift of 61.34 meV when the temperature increased from 10 to 300 *** component ratio of S to Se in the CdSxSe1-x quantum dots was valued by both the X-ray diffraction data and photoluminescence peak energy at room temperature according to Vegard ***,the parameters of the Varshni relation for CdS0.9Se0.1 materials were also obtained using photoluminescence peak energy as a function of temperature and the best-fit curve:α=(3.5 ± 0.1)10-4 eV/K,and β=210 ± 10 K (close to the Debye temperature θD of the material).

关键词： CdSxSe1-x quantum dots temperature dependent photoluminescence

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角茴香中1个新的吡嗪类生物碱

药学学报 2024年第1期59卷 183-187页

作者：刘云胡梦雅张文静范雨欣徐瑞雯朱登辉孙彦君冯卫生陈辉河南中医药大学药学院河南郑州450046 呼吸疾病中医药防治省部共建协同创新中心河南郑州450046

采用硅胶、ODS、MCI等柱色谱以及半制备液相等现代色谱分离技术对角茴香(Hypecoum erectum L.)正丁醇萃取部位的化学成分进行分离纯化,得到4个吡嗪类生物碱。运用现代波谱学方法(1D NMR、2D NMR、UV、IR、MS等)鉴定结构分别为hyperectpy... 详细信息

采用硅胶、ODS、MCI等柱色谱以及半制备液相等现代色谱分离技术对角茴香(Hypecoum erectum L.)正丁醇萃取部位的化学成分进行分离纯化,得到4个吡嗪类生物碱。运用现代波谱学方法(1D NMR、2D NMR、UV、IR、MS等)鉴定结构分别为hyperectpyrazin A(1)、1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol(2)、2-hydroxymethyl-6-methylpyrazin(3)和pyrazine-2-carboxylic acid(4)。化合物1为1个新的吡嗪类生物碱,化合物2~4为首次从角茴香中分离得到,并首次通过Mo_(2)(OAc)_(4)诱导的CD谱确定了化合物2的绝对构型。采用乙酰胆碱酯酶抑制模型和脂多糖诱导的RAW264.7巨噬细胞炎症模型,对化合物1~4进行体外活性评价,其中化合物2和4表现出一定的乙酰胆碱酯酶抑制活性,在终浓度为50μmol·L^(-1)时对乙酰胆碱酯酶的抑制率分别为44.40%和43.99%。

关键词：角茴香化学成分吡嗪类生物碱 hyperectpyrazin A 乙酰胆碱酯酶抑制活性

基于贝叶斯分类器和回波物理特征的C波段雷达非气象回波识别方法和性能分析

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大气科学 2024年第3期48卷 823-836页

作者：李巧戚友存张哲杨毅朱自伟王楠胡启元中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 深圳市国家气候观象台深圳518040 中国科学院大学北京100049 兰州大学大气科学学院兰州730000 陕西省气象局西安710014

天气雷达在观测过程中,通常会受到非气象因子的干扰,产生非气象回波,从而严重影响雷达定量降水估计的精度和短临降水预报的性能。本文使用陕西省西安、延安等7部C波段多普勒天气雷达的体扫观测,构建了基于贝叶斯分类器和回波物理特征的... 详细信息

天气雷达在观测过程中,通常会受到非气象因子的干扰,产生非气象回波,从而严重影响雷达定量降水估计的精度和短临降水预报的性能。本文使用陕西省西安、延安等7部C波段多普勒天气雷达的体扫观测,构建了基于贝叶斯分类器和回波物理特征的质量控制方法:首先人工提取每部雷达的降水回波、地物回波和晴空回波的反射率因子,并基于提取的不同类型雷达回波,分析了陕西省7部雷达不同类型雷达回波的反射率因子、反射率因子水平纹理、反射率因子沿径向的变化梯度、5 dBZ回波高度、反射率垂直梯度的变化特征,统计得到不同类型雷达回波对应特征量的概率密度分布函数;然后基于统计的概率密度分布函数建立贝叶斯分类器,对雷达回波进行初步识别;在此基础上,结合雷达回波物理特征设计了太阳尖峰识别方法、孤立点去除方法和回波空洞填补方法,进一步识别雷达回波;最后去除非气象回波,得到质量控制后的降水回波数据。利用2019年7~9月陕西省7部雷达的体扫观测数据,系统地分析了雷达质量控制方法的性能,同目前陕西省业务运行的雷达数据质量控制结果进行了对比分析,并使用HSS评分(Heidke skill score)评估了质量控制结果的准确率。结果表明,研发的基于贝叶斯分类器和回波物理特征的雷达质量控制方法能够较好地识别降水回波和非降水回波,识别效果优于业务使用结果,7部雷达数据质量控制结果的HSS评分均在0.75以上。

关键词：多普勒天气雷达质量控制贝叶斯分类器回波类型识别

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中国妇幼保健 2024年第12期39卷 2301-2304页

作者：周淑静黄佩佩朱张茜浙江中医药大学浙江杭州310000 温州市人民医院超声医学科浙江温州325000

目的探究经颅彩色多普勒超声参数与肺超声评分的相关性及对新生儿呼吸窘迫综合征的诊断价值。方法收集2020年3月—2022年3月温州市人民医院收治的98例疑似新生儿呼吸窘迫综合征患儿,进行经颅彩色多普勒超声检查,检查后确诊为呼吸窘迫... 详细信息

目的探究经颅彩色多普勒超声参数与肺超声评分的相关性及对新生儿呼吸窘迫综合征的诊断价值。方法收集2020年3月—2022年3月温州市人民医院收治的98例疑似新生儿呼吸窘迫综合征患儿,进行经颅彩色多普勒超声检查,检查后确诊为呼吸窘迫综合征的49例患儿为研究组,非呼吸窘迫综合征的49例新生儿为对照组。比较两组患儿经颅彩色多普勒超声参数,比较不同严重程度的研究组患儿经颅彩色多普勒超声参数,比较不同严重程度的研究组患儿肺超声评分,分析经颅彩色多普勒超声参数、肺超声评分与疾病严重程度的关系,分析经颅彩色多普勒超声参数与肺超声评分的相关性,分析经颅彩色多普勒超声参数对呼吸窘迫综合征的诊断意义。结果对照组收缩期峰值血流速度(PSV)、平均血流速度(MFV)、舒张末期血流速度(EDV)、搏动指数(PI)、阻力指数(RI)分别为(43.26±8.69)cm/s、(14.53±4.58)cm/s、(25.75±6.84)cm/s、(0.57±0.09)、(0.89±0.31);研究组PSV、MFV、EDV、PI、RI分别为(33.61±6.37)cm/s、(9.07±3.46)cm/s、(18.11±5.82)cm/s、(0.71±0.11)、(1.39±0.45)。两组PSV、MFV、EDV、PI、RI比较差异均有统计学意义(t=6.269,6.658,5.955,6.895,6.405,均P<0.05)。非危重组、危重组、急危重组患儿PSV、MFV、EDV、PI、RI比较,差异均有统计学意义(均P<0.05)。非危重组、危重组、急危重组肺超声评分分别为(14.56±5.93)分、(18.11±6.04)分、(21.57±6.49)分,差异有统计学意义(F=3.158,P<0.05)。PI、RI、肺超声评分与疾病严重程度呈正相关(r=0.590,0.619,0.548,均P<0.05),PSV、MFV、EDV与疾病严重程度呈负相关(r=-0.583,-0.611,-0.572,均P<0.05)。PI、RI与肺超声评分呈正相关(r=0.585,0.623,均P<0.05),PSV、MFV、EDV与肺超声评分呈负相关(r=-0.576,-0.609,-0.583,均P<0.05)。与PSV、MFV、EDV、PI、RI单项诊断相比,5项联合对呼吸窘迫综合征的诊断价值较高(P<0.05)。结论经颅彩色多普勒超声参数对新生儿呼吸窘迫综合征有较强的诊断价值,且与肺超声评分具有一定的相关性,可用于新生儿呼吸窘迫综合征患儿病情评估及诊断。

关键词：经颅彩色多普勒超声参数肺超声评分新生儿呼吸窘迫综合征

Chinese research into severe ulcerative colitis has increased in quantity and complexity

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World Journal of Clinical Cases 2018年第3期6卷 35-43页

作者： cheng-xin Luo Zhong-hui Wen Yu Zhen zhu-Jun Wang jing-xi Mu Min zhu Qin Ouyang hu zhang Department of Gastroenterology West China Hospital Sichuan University

AIM To investigate the current state of research output from Chinese studies into severe ulcerative colitis(SUC) using a bibliometric analysis of publications. METHODS The contents of the Chinese periodical databases WANFANG, VIP, and China National Knowledge Infrastructure were searched for all papers regarding UC or SUC published in last the 15 years (from 2001 to 2015). The number of publications in each year was recorded to assess the temporal trends of research output. All SUC related publications were downloaded and the complexity of this research was evaluated with methods described previously. The number of patients with SUC reported each year was recorded and their clinical characteristics were analyzed using information available in the relevant papers. RESULTS There were 13499 publications regarding UC published in Chinese medical journals between 2001 and 2015, of which 201 focused on SUC. The number of publications increased rapidly with more than half of all papers being published in the most recent 5-year period. There was a significant increase in analyticalstudies and clinical trials over the study period (P ximab in disease management. About 6222 patients with SUC were reported in the 201 SUC relevant papers, with a ratio of male/female of 1.38. The number of patients reported in each 5-year period significantly increased. The colectomy rate and short-term mortality rate were 7.7% and 0.8% respectively. The most commonly employed operation was total proctocolectomy with ileal pouch-anal *** The output and complexity of research related to SUC in China increased significantly over the previous 15 years, however few of these

关键词： Bibliometric analysis Clinical trials Salvage therapy Complexity Severe ulcerative colitis Temporal trends Traditional Chinese Medicine

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS-CoV-2 Omicron strain infection in China:A national multicenter survey of 35,566 individuals

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 113-120页

作者： Meng-Fan Liu Rui-xia Ma xian-Bao Cao hua zhang Shui-Hong Zhou Wei-Hong Jiang Yan Jiang jing-Wu Sun Qin-Tai Yang Xue-Zhong Li Ya-Nan Sun Li Shi Min Wang xi-cheng Song Fu-Quan chen xiao-Shu zhang Hong-Quan Wei Shao-Qing Yu Dong-Dong zhu Luo Ba Zhi-Wei Cao Xu-Ping xiao xin Wei Zhi-Hong Lin Feng-Hong chen Chun-Guang Shan Guang-Ke Wang jing Ye Shen-Hong Qu Chang-Qing Zhao Zhen-Lin Wang hua-Bin Li Feng Liu xiao-Bo Cui Sheng-Nan Ye Zheng Liu Yu Xu xiao Cai Wei huang Ru-xin zhang Yu-Lin Zhao Guo-Dong Yu Guang-gang Shi Mei-Ping Lu Yang Shen Yu-Tong Zhao Jia-Hong Pei Shao-Bing xie Long-gang Yu Ye-Hai Liu Shao-Wei Gu Yu-cheng Yang Lei cheng Jian-Feng liu Graduate School of Beijing University of Chinese Medicine BeijingChina Department of Otorhinolaryngology Head and Neck Surgery China-Japan Friendship HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First People's Hospital of YinchuanYinchuanChina Department of Otorhinolaryngology The First People's Hospital of Yunnan ProvinceKunmingChina Department of Otorhinolaryngology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Xiangya Hospital Central South UniversityChangshaChina Department of Otorhinolaryngology Head and Neck Surgery The Affiliated Hospital of Qingdao UniversityQingdaoChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of USTCHefeiChina Department of Otorhinolaryngology Head and Neck Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Qilu Hospital of Shandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbinChina Department of Otolaryngology The Second Hospital of Shandong UniversityShandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery Peking University People's HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery Yantai Yuhuangding HospitalQingdao UniversityYantaiChina Department of Otorhinolaryngology Head and Neck Surgery Xijing HospitalThe Fourth Military Medical UniversityXi'anChina Gansu Provincial Center for Disease Control and Prevention LanzhouChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of China Medical UniversityShenyangChina Department of Otorhinolaryngology Head and Neck Surgery Tongji Hospit

Objective:This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in ***:This study was conducted by 45 tertiary Grade-A hospitals in *** and offline questionnaire data were obtained from patients infected with COVID-19 between December 28,2022,and February 21,*** collected information included basic demographics,medical history,smoking and drinking history,vaccination history,changes in olfactory and gustatory functions before and after infection,and other postinfection symptoms,as well as the duration and improvement status of olfactory and gustatory ***:Complete questionnaires were obtained from 35,566 *** overall incidence of olfactory and taste dysfunction was 67.75%.Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste *** received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such *** infection,the average olfactory and taste VAS scores were 8.41 and 8.51,respectively;after infection,they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the *** median duration of dysosmia and dysgeusia was 15 and 12 days,respectively,with 0.5%of patients having symptoms lasting for more than 28 *** overall self-reported improvement rate was 59.16%.Recovery was higher in males,never smokers,those who received two or three vaccine doses,and those that had never experienced dental health issues,or chronic accompanying ***:The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in *** and prognosis are influenced by several factors,including sex,SARS-CoV-2 vaccination,history of head-facial trauma,nasal and oral health status,smoking and drinking history,and the persistence of accompanying symptoms.

关键词： epidemiologic studies incidence olfactory disorders prognosis SARS-CoV-2 taste disorders

西安市大气污染物时空演化特征及对人体健康评价

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环境科学 2024年第6期45卷 3746-3755页

作者：徐传奇白杨唐远薇张欣宇王志瑞呼婧婧杨锦涛山西师范大学地理科学学院太原030031 中国气象局乌鲁木齐沙漠气象研究所塔克拉玛干沙漠气象国家野外科学观测研究站新疆沙漠气象与沙尘暴重点实验室新疆树木年轮生态实验室乌鲁木齐830002

西安市是我国西北政治、经济和文化中心,工业发达,但空气污染事件对社会经济的高质量发展带来极大挑战,探究该地区大气污染特征并厘清其对人体健康产生的影响至关重要.对西安市2015~2021年大气污染物的时空趋势变化特征进行分析;其次,... 详细信息

西安市是我国西北政治、经济和文化中心,工业发达,但空气污染事件对社会经济的高质量发展带来极大挑战,探究该地区大气污染特征并厘清其对人体健康产生的影响至关重要.对西安市2015~2021年大气污染物的时空趋势变化特征进行分析;其次,利用空气质量指数(AQI)、综合空气质量指数(AAQI)和空气质量健康指数(HAQI)结合Air Q2.2.3模型量化各污染物对人体的健康效应.结果发现,研究区整体空气质量呈良好状态,各大气污染物呈现下降态势.污染物主要以PM_(10)、PM_(2.5)和O_(3)为主,地形特征和人为排放的混合式污染是研究区的主要污染特征.AAQI和HAQI相较于AQI对污染水平表现出较好的分类效果,HAQI揭示研究区全年约有80%左右的人口暴露于不健康的空气中,其中冬季暴露于不健康空气中的人群最多,其次为秋季、春季,夏季最少.Air Q2.2.3模型量化出归因于PM_(2.5)、PM_(10)、SO_(2)、CO、NO_(2)和O_(3)的总死亡率比例分别为0.99%、2.04%、0.41%、1.72%、8.76%和3.67%,且呼吸系统和心脑血管疾病死亡率的可归因比例与总死亡率变化规律较为一致.

关键词：大气污染物时空演化空气质量人体健康超额风险

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西宁市富铁地下水分布特征及影响因素分析

水文地质工程地质 2024年第5期51卷 45-55页

作者：刘春燕刘景涛荆继红张玉玺朱亮黄冠星张英陈玺周冰杨明楠解飞李备福建省水循环与生态地质过程重点实验室福建厦门361021 中国地质科学院水文地质环境地质研究所河北石家庄050061

地下水是西宁市的重要供水水源,调查发现其地下水中富铁,限制了开发利用,而针对不同类型含水层中富铁地下水分布特征及其成因缺乏研究。以144组地下水样品水化学测试数据为基础,结合地质和水文地质条件特征,借助统计学和地统计学等方法... 详细信息

地下水是西宁市的重要供水水源,调查发现其地下水中富铁,限制了开发利用,而针对不同类型含水层中富铁地下水分布特征及其成因缺乏研究。以144组地下水样品水化学测试数据为基础,结合地质和水文地质条件特征,借助统计学和地统计学等方法,研究了不同类型含水层地下水中铁含量的分布特征及其影响因素。结果表明:松散岩类孔隙含水层(Ⅰ区)地下水中Fe超过质量浓度0.3 mg/L的水占27.85%,分别是碎屑岩类裂隙孔隙含水层(Ⅱ区)和基岩裂隙含水层(Ⅲ区)的1.6倍和2.7倍,富铁地下水(质量浓度大于0.3 mg/L)在建设用地中的比例明显高于其他土地利用类型区;还原环境和人类活动(如工业废水、生活污水、富铁河水的入渗)可能是影响Ⅰ区地下水中铁含量升高的主要因素,Ⅱ区中富铁地下水除了受还原环境的影响外,农业氮肥的施用和生活污水的排放也是重要影响因素,Ⅲ区中富铁地下水主要受控于还原条件;在区域尺度上,富铁地下水沿河流呈条带或斑状分布,原生地层中铁矿床和人类活动(工业废水)释放的铁是研究区浅层地下水中铁离子的主要来源,地下水中铁离子的迁移和富集主要受还原条件的控制,径流条件也起到一定作用,与pH无明显相关性,未引起明显的“盐效应”。研究结果可为西宁市及类似干旱—半干旱区城市水环境管理提供科学依据。

关键词：地下水人类活动含水层 Fe分布特征影响因素西宁市

Engineering subcellular-patterned biointerfaces to regulate the surface wetting of multicellular spheroids

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Nano Research 2018年第10期11卷 5704-5715页

作者： Luying Wang Pingqiang Cai jing Luo Feilong zhang Jian Liu Yupeng chen Zhongpeng zhu Yongyang Song Bingquan Yang xi Liu xiaodong chen Shutao Wang Beijing National Laboratory for Molecular Sciences (BNLMS) Key Laboratory of Green Printing Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science CAS Center for Excellence in Nanoscience Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore

Studying the wetting behaviors of multicellular spheroids is crucial in the fields of embryo implantation, cancer propagation, and tissue repair. Existing strategies for controlling the wetting of multicellular spheroids mainly focus on surface chemistry and substrate rigidity. Although topography is another important feature in the biological micro-environment, its effect on multicellular spheroid wetting has seldom been explored. In this study, the influence of topography on the surface wetting of multicellular spheroids was investigated using subcellular- patterned opal films with controllable colloidal particle diameters （from 200 to 1,500 nm）. The wetting of hepatoma carcinoma cellular （Hep G2） spheroids was impaired on opal films compared with that on flat substrates, and the wetting rate decreased as colloidal particle diameter increased. The decrement reached 48.5% when the colloidal particle diameter was 1,500 nm. The subcellular-patterned topography in opal films drastically reduced the cellular mobility in precursor films, especially the frontier cells in the leading edge. The frontier cells failed to form mature focal adhesions and stress fibers on micro-patterned opal films. This was due to gaps between colloidal particles leaving adhesion vacancies, causing weak cell-substrate adhesion and consequent retarded migration of Hep G2 spheroids. Our study manifests the inhibiting effects of subcellular-patterned topography on the wetting behaviors of multicellular spheroids, providing new insight into tissue wetting-associated treatments and biomaterial design.

关键词： topography wetting multicellular spheroids cell adhesion collective migration biointerfaces