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Dynamic Variations and Influencing Factors of Groundwater Levels in Lhasa City

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Wuhan University Journal of Natural Sciences 2005年第4期10卷 665-673页

作者： FANJi-hui LIUQiao zhangyan CHENGGen-wei FANXiang-de LUWen-ming InstituteofMountainHazardsandEnvironment ChineseAcademyofSciencesChengdu610041SichuanChina／／GraduateSchooloftheChineseAcademyofSciencesBeijing100039China DepartmentofTouristandEnvironmentalScience NanyangTeacher＇sCollegeNanyang473061HenanChina InstituteofMountainHazardsandEnvironment ChineseAcademyofSciencesChengdu610041SichuanChina~ TibetGeo-EnvironmentalMonitoringStation Lhasa850000TibetChina

This paper focuses on the dynamic variation of groundwater level in Lhasacity. According to the data, the obvious characteristic of the groundwater level of the city is thatit is changing seasonally. Lhasa is divided into three districts according to hydrogeologicalconditions: the alluvial plain of the Lhasa-river, the alluvial plain of the Doilung-river, and thealluvial fan of inter mountain, which presents a downward trend, a slight upward trend and basicallystabilizing trend over the years individually. The analysis indicates that meteorological andhydrological factors lead to the obvious dynamic change of the groundwater level. However, more andmore human activities and over-exploitation of the groundwater cause the downward trend inthegroundwater level.

关键词： Lhasa groundwater level dynamic variation factor

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碳纤维补强预应力钢筒混凝土管试验研究

水科学与工程技术 2024年第4期 74-79页

作者：张文涛陈章言张静刘超河北省水利工程局集团有限公司石家庄050021

针对预应力钢筒混凝土管道(PCCP)在使用过程中出现的裂缝、断丝等劣化现象,提出一种“一纵三环”黏贴碳纤维布加固PCCP管的方法。为验证该法修复PCCP断丝管的效果,采用3根2.2 m直径PCCP管在管芯混凝土内表面黏贴碳纤维增强复合材料(CFRP... 详细信息

针对预应力钢筒混凝土管道(PCCP)在使用过程中出现的裂缝、断丝等劣化现象,提出一种“一纵三环”黏贴碳纤维布加固PCCP管的方法。为验证该法修复PCCP断丝管的效果,采用3根2.2 m直径PCCP管在管芯混凝土内表面黏贴碳纤维增强复合材料(CFRP)进行加固试验。按不同温度和湿度组合黏贴CFRP,并分别在自然养护7 d和浸水30 d后进行正拉接性能试验。结果表明,自然养护条件下正拉接强度随着黏贴温度的升高而升高,随湿度增加呈先降低再升高的趋势;浸水养护后正拉接强度有所降低,为自然养护强度的80%。

关键词：预应力钢筒混凝土管(PCCP) 碳纤维增强复合材料(CFRP) 加固黏接性能

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藤茶的食用历史及安全性

现代食品科技 2024年第7期40卷 363-368页

作者：张典典高家东戴彰言张文虎张友胜刘军广东省农业科学院蚕业与农产品加工研究所农业农村部功能食品重点实验室广东省农产品加工重点实验室广东广州510610 广东省农作物种质资源保存与利用重点实验室广东省农业科学院农业生物基因研究中心广东广州510640

藤茶是近几年我国南部省份兴起的一种特色茶饮植物。现代科学研究证明藤茶中含有丰富的黄酮类和多糖类活性成分,具有消炎抗菌、提高免疫力、保肝护肝、降血糖降血脂等功能,是预防、防治慢性代谢性疾患非常有前景的一种特色植物。该文就... 详细信息

藤茶是近几年我国南部省份兴起的一种特色茶饮植物。现代科学研究证明藤茶中含有丰富的黄酮类和多糖类活性成分,具有消炎抗菌、提高免疫力、保肝护肝、降血糖降血脂等功能,是预防、防治慢性代谢性疾患非常有前景的一种特色植物。该文就藤茶的食用历史与安全性进行了文献综述,同时就其产业化开发利用提供了系列思路,拟为其植物资源的合理利用及产品开发提供依据。

关键词：藤茶食用历史安全性产业化开发利用

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Association between central obesity and executive function as assessed by stroop task performance:A functional near-infrared spectroscopy study

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Journal of Innovative Optical Health Sciences 2018年第1期11卷 37-46页

作者： zhangyan Deng Qin Huang Jiaai Huang Weixia Zhang Changzhu Qi Xia Xu Graduate School Wuhan Sports University Wuhan 430079P.R.China College of Health Science Wuhan Sports University Wuhan 430079P.R.China Hubei Key Laboratory of Exercise Training and Monitoring Wuhan Sports University 461 Luoyu Road Wuhan 430079P.R.China

Recent studies have suggested a link between executive function(EF)and *** oftenadopt body mass index(BM),which reflects the distribution of subcutaneous fat,as the solemarker of obesity;however,BMI is inappropriate to distinguish central obesity,which indicatesthe centralized distribution of visceral *** fat compared with subcutaneous fat repre-sents greater relative lipid turnover and may increase the risk of cognitive decline in older ***,the relationship between EF and central obesity is largely unknown,particularly inyoung ***,we used waist circumference(WC)as a marker of central obesity andinvestigated diferent sensitivities between BMI and WC in the brain function.A total of 26healthy young adults(aged 18-25 years;42%female)underwent functional near-infrared spec-troscopy *** was assessed using the Stroop task,which is a classical measurementof EF.A significant Stroop effect was observed in the behavioral and hemodynamic ***,we observed that behavioral interference on the Stroop task varied much more insubjects with higher BMI and WC than those subjects with *** BMI and WC wereassociated with a decreased hemodynamic response during the Stroop task specifically in the pre-frontal cortex(PFC).Compared to BMI,WC was more closely connected with inhibitory controland revealed right lateralized PFC *** findings suggest that WC is a reliable indicatorof brain function in young adults and propose a relationship bet ween EF and central obesity.

关键词： Executive function central obesity fNIRS young adult

My Teacher and Helpmate

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China Today 2005年第4期54卷 34-35页

作者： zhangyan firstdeputyeditor-in-chiefofChinaToday

IN my life I have made many friends, both Chinese and foreign, quite a number of them intimate to the extent that I can repose in them my full confidence. Israel Epstein, known as Eppy to his friends, is one of the mo... 详细信息

关键词：中国爱泼斯坦生平事迹生活方式

The estimate of sea ice resources quantity in the Bohai Sea based on NOAA/AVHRR data

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Acta Oceanologica Sinica 2012年第1期31卷 33-40页

作者： YUAN Shuai GU Wei XU Yingjun WANG Ping HUANG Shuqing LE zhangyan CONG Jianou State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of EducationBeijing 100875China National Marine Environmental Monitoring Center State Oceanic AdministrationDalian 116023China Meteorological Department of Langfang Hebei 065000China

The research on sea ice resources is the academic base of sea ice exploitation in the Bohai Sea. According to the ice-water spectrum differences and the correlation between ice thickness and albedo, this paper comes up with a sea ice thickness inversion model based on the NOAA/AVHRR data. And then a sea ice resources quantity （SIQ） time series of Bohai Sea is established from 1987 to 2009. The results indicate that the average error of inversion sea ice thickness is below 30%. The maximum sea ice resources quantity is about 6×109 m3 and the minimum is 1.3×109 m3. And a preliminary analysis has been made on the errors of the estimate of sea ice resources quantity （SIQ）.

关键词： sea ice in the Bohai Sea sea ice resources quantity NOAA/AVHRR error analysis

乙酰半胱氨酸联合沙美特罗替卡松对稳定期COPD患者血清PCT、肺功能的影响

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中外医疗 2024年第14期43卷 17-21页

作者：龚章燕赖莉严永枝李云英黔西南布依族苗族自治州妇幼保健院内科贵州兴义562400

目的分析稳定期慢性阻塞性肺疾病(Chronic Obstructive Pulmonary Disease, COPD)患者联合应用乙酰半胱氨酸、沙美特罗替卡松治疗效果以及对血清降钙素原(Procalcitonin, PCT)、肺功能的影响。方法单纯随机选取2021年1月—2023年11月... 详细信息

目的分析稳定期慢性阻塞性肺疾病(Chronic Obstructive Pulmonary Disease, COPD)患者联合应用乙酰半胱氨酸、沙美特罗替卡松治疗效果以及对血清降钙素原(Procalcitonin, PCT)、肺功能的影响。方法单纯随机选取2021年1月—2023年11月黔西南布依族苗族自治州妇幼保健院收治的100例稳定期COPD患者为研究对象,按随机数表法分为对照组(n=50,单用沙美特罗替卡松治疗)、观察组(n=50,应用乙酰半胱氨酸联合沙美特罗替卡松治疗),比较两组治疗效率、症状消失时间、PCT水平、血清白介素水平、肺功能、不良反应发生率。结果观察组治疗效率为90.00%,高于对照组的74.00%,差异有统计学意义(χ^(2)=4.336,P=0.037)。观察组咳嗽症状消失时间、咳痰症状消失时间、呼吸气促症状消失时间、干湿啰音消失时间均短于对照组,差异有统计学意义(P均0.05)。结论稳定期COPD患者临床治疗过程中联合应用乙酰半胱氨酸、沙美特罗替卡松具有确切效果,能够加快症状消失,下调PCT与血清白介素表达,减轻肺功能损伤,并且未出现严重的药物不良反应,安全性高。

关键词：慢性阻塞性肺疾病稳定期乙酰半胱氨酸沙美特罗替卡松降钙素原肺功能

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Intercalation and hybrid heterostructure integration of two-dimensional atomic crystals with functional organic semiconductor molecules

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Nano Research 2020年第11期13卷 2917-2924页

作者： Wen He Han Zang Songhua Cai zhangyan Mu Cheng Liu Mengning Ding Peng Wang Xinran Wang Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing210093China Jiangsu Key Laboratory of Artificial Functional Materials College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Applied Physics The Hong Kong Polytechnic UniversityHung Hom999077KowloonHong KongChina Research Center for Environmental Nanotechnology(ReCENT) Nanjing UniversityNanjing210023China

Van der Waals(vdW)integration affords semiconductor heterostructures without constrains of lattice matching and opens up a new realm of functional devices by design.A particularly interesting approach is the electrochemical intercalation of two-dimensional(2D)atomic crystal and formation of superlattices,which can provide scalable production of novel vdW ***,this approach has been limited to the use of organic cations with non-functional aliphatic chains,therefore failed to take the advantage of the vast potentials in molecular functionalities(electronic,photonic,magnetic,etc.).Here we report the integration of 2D crystal(MoS_(2),WS_(2),highly oriented pyrolytic graphite(HOPG),WSe_(2) as model systems)with electrochemically inert organic molecules that possess semiconducting characteristics(including perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA),pentacene and fullerene),through on-chip electrochemical *** unprecedented long-range spatial feature of intercalation has been achieved,which allowed facile assembly of a vertical MoS_(2)-PTCDA-Si *** intercalated heterostructure shows significant modulation of the lateral transport,and leads to a molecular tunneling characteristic at the vertical *** general intercalation of charge neutral and functional molecules defines a versatile platform of inorganic/organic hybrid vdW heterostructures with significantly extended molecular functional building blocks,holding great promise in future design of nano/quantum devices.

关键词： transition metal dichalcogenide electrochemical intercalation perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA) organic semiconductor inorganic/organic heterostructure

C_(9)^(+)重芳烃加氢脱烷基反应的热力学分析

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石油炼制与化工 2024年第9期55卷 42-51页

作者：谢仕林莫昌艺杨平严张艳张鹏飞任亮胡志海中石化石油化工科学研究院有限公司北京100083

选取两种典型C_(9)^(+)重芳烃原料,其烃组成以三甲苯和甲乙苯为主。选择三甲苯和甲乙苯为模型化合物,计算了其在350~650℃温度范围内加氢脱烷基反应的标准摩尔反应焓变、标准摩尔吉布斯自由能变和标准平衡常数,并进行了反应热力学分析... 详细信息

选取两种典型C_(9)^(+)重芳烃原料,其烃组成以三甲苯和甲乙苯为主。选择三甲苯和甲乙苯为模型化合物,计算了其在350~650℃温度范围内加氢脱烷基反应的标准摩尔反应焓变、标准摩尔吉布斯自由能变和标准平衡常数,并进行了反应热力学分析。结果表明:三甲苯和甲乙苯的加氢脱烷基反应均为放热反应,且反应的放热量与分子结构的对称性成负相关关系,这可能与克服甲基或乙基空间位阻相关;在标准状态下三甲苯和甲乙苯脱烷基反应可自发进行,平衡状态下三甲苯和甲乙苯脱烷基反应进行程度较深,且随着脱烷基数目的增加,脱烷基反应进行程度增加,而提高反应温度不利于反应向脱烷基反应方向移动。

关键词： C_(9)^(+) 重芳烃加氢脱烷基三甲苯甲乙苯反应热力学