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Vibrational Properties Study on Canter Fractal Structure

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Chinese Physics Letters 1995年第2期12卷 91-94页

作者： ZHANG Haifeng TANG Tao xu wenlan LI Yongping Department of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026 Department of Physics University of Science and Technology of ChinaHefei 230026 National Infrared Laboratory Shanghai Institute of Technical PhysicsAcademia SinicaShanghai 200083

A new system of Canter fractal models was created and studied,the density of states(DOS)as well as wavefunctions of the phonon in this kind of structure were calculated and discussed,in which it shows a new kind of br... 详细信息

关键词： Fractal DOS fractal

Development of an infrared detector: Quantum well infrared photodetector

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 969-977页

作者： LU Wei LI Ling ZHENG HongLou xu wenlan XIONG DaYuan National Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Ministry of Education Laboratory for Polarization Material and Device College of Information Sciences and TechnologyEast China Normal UniversityShanghai 200241China

The progress in the quantum well infrared photo-detector (QWIP) based on quantum confinement in semiconductor in recent 10 years has been reviewed. The differences between QWIP and the HgCdTe (HCT) infrared detector as well as their compensation are analyzed. The outlook for near-future trends in QWIP technologies is also presented.

关键词： infrared photoelectronics QWIP progress development trend

APPLICATION OF THE EMBEDDED ATOM METHOD TO PHONON DISPERSIONS IN COPPER

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Chinese Physics Letters 1988年第5期5卷 217-220页

作者： LUO Ningsheng xu wenlan SHEN Shuechu YE Yiying Institute of Technical Physics Academia SinicaShanghai Physics Department Wuhan UniversityWuhan

The force constants between planes in lattice dynamics have been derived from a new model set by the Embedded Atom Method(EAM),based on tile results from density-functional *** semiempirical functions for Cu have been obtained by EAM,and the force constants between planes of Cu are calculated,which produce phonon dispersions in agreement with experiments.

关键词： theory. constants phonon

机械合金化法制备Mg-Zn合金的耐腐蚀性能

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特种铸造及有色合金 2018年第6期38卷 600-603页

作者：付广艳许文兰谢焕璋沈阳化工大学机械工程学院

采用高能球磨及真空热压烧结方法制备了4种不同Zn含量的Mg-Zn合金。通过在SBF模拟体液中进行动电位极化曲线测试及浸泡24h的质量损失试验,对比研究了4种Mg-Zn合金的耐蚀性。结果表明,球磨粉末与烧结的合金锭中均含有第二相Mg2Zn3、MgZn2... 详细信息

采用高能球磨及真空热压烧结方法制备了4种不同Zn含量的Mg-Zn合金。通过在SBF模拟体液中进行动电位极化曲线测试及浸泡24h的质量损失试验,对比研究了4种Mg-Zn合金的耐蚀性。结果表明,球磨粉末与烧结的合金锭中均含有第二相Mg2Zn3、MgZn2,且Zn的含量越高,第二相含量越高。Mg-5Zn、Mg-10Zn合金的质量损失明显大于Mg-1Zn、Mg-3Zn合金,第二相Mg2Zn3、MgZn2是影响Mg-Zn合金耐蚀性的主要原因。Zn元素在腐蚀液中生成的一定量的ZnO钝化膜可以与Mg(OH)2共同保护基体,所以Mg-3Zn合金的耐蚀性在4种合金中最好。

关键词： Mg-Zn合金模拟体液耐蚀性机械合金化

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

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宫颈癌年轻患者临床特征分析

大医生 2019年第7期4卷 36-37页

作者：徐文兰新疆伊犁州妇幼保健院妇科新疆伊犁835000

目的观察分析宫颈癌年轻患者临床特征。方法选取2017年8月至2018年8月新疆伊犁州妇幼保健院收治的75例40岁以内的宫颈癌患者为观察组,并选取同期73例年龄>40岁的宫颈癌患者作为对照组,分析两组患者的基本资料及临床症状。结果观察组患... 详细信息

目的观察分析宫颈癌年轻患者临床特征。方法选取2017年8月至2018年8月新疆伊犁州妇幼保健院收治的75例40岁以内的宫颈癌患者为观察组,并选取同期73例年龄>40岁的宫颈癌患者作为对照组,分析两组患者的基本资料及临床症状。结果观察组患者的接触性阴道流血63例,占比86.30%;白带增多14例,占比18.67%;腰痛或者腹痛5例,占比6.67%;无症状13例,占比17.33%。对照组患者的接触性阴道流血56例,占比76.71%;白带增多11例,占比15.07%;腰痛或者腹痛4例,占比5.48%;无症状20例,占比27.40%。观察组患者的接触性阴道流血、白带增多、腰痛或者腹痛、无症状等临床症状比较差异无统计学意义(P>0.05);观察组患者的阴道不规则流血20例,占比26.67%,对照组患者的阴道不规则流血9例,占比12.33%,观察组患者阴道不规则流血临床症状明显较多(P<0.05)。结论接触性阴道流血为年轻妇女宫颈癌的危险信号,诊断上应提高对年轻妇女宫颈癌的警惕。

关键词：宫颈癌临床特征预后影响

Laboratory evaluation of high-friction thin overlays for pavement preservation

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 936-948页

作者： Ouming xu Rentao xu Lintong JIN School of Highway Chang’an UniversityXi’an 710064China School of Materials Science and Engineering Chang’an UniversityXi’an 710061China

Traditional asphalt concrete(AC)and stone matrix asphalt(SMA),which are used as thin asphalt overlays,are common maintenance strategies to enhancing ride quality,skid resistance,and ***,several studies have used a novel asphalt mixture known as a high-friction thin overlay(HFTO)to improve surface ***,it remains uncertain whether the laboratory properties of HFTO differ significantly from those of conventional *** study aims to evaluate the laboratory properties of HFTO mixtures and compare them with those of AC and *** mixtures with nominal maximum size of 9.5 mm were produced in the laboratory,and performance tests were conducted,including wheel tracking test,low temperature flexural creep test,moisture susceptibility test,Cantabro Abrasion Test,Marshall Test,sand patch test,British pendulum test,and indoor tire-rollingdown *** results showed that the HFTO exhibited a lower tire/pavement noise than the AC and ***,HFTO had superior high-temperature stability,larger macro texture,and higher skid resistance in comparison to those of AC,but lower than those of ***,HFTO mixtures may be considered a suitable replacement for traditional AC mixtures in regions where skid resistance and noise reduction are concerns.

关键词： road engineering pavement maintenance high friction thin overlay performance skid resistance tire/pavement noise

Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu Hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

Granting strength to aerogel fibers through encapsulation

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Science China Materials 2024年第4期67卷 1365-1366页

作者： Wenhui xu Department of Basic Chemistry School of PharmacyJiangxi University of Chinese MedicineNanchang 330004China

Aerogel fibers, distinguished by their lightweight nature, pronounced porosity, large surface area, and superior thermal insulation properties, have diversified applications in thermal management, energy devices, and environmental remediation[1]. However, compared with monolithic ones, these fibershaped aerogels exhibit limited mechanical strength and resilience due to their one-dimensional small size.

关键词： strength fibers thermal