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High photoelectric conversion efficiency and fast relaxation time of fa_(0.4)MA_(0.6)PbI_(3) applied in ultrafast modulation of terahertz waves

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Journal of Energy Chemistry 2024年第4期91卷 299-305页

作者： Zhibo Xu Ying Zeng Xinran Zhao Xiaoyin Chen Aoyu fan Furi ling Jiang Li Jianquan Yao School of Optics and Electronic Information Huazhong University of Science and TechnologyWuhan 430074HubeiChina College of Precision Instrument and Optoelectronics Engineering Tianjin UniversityTianjin 300072China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900SichuanChina School of Information Engineering Wuhan University of TechnologyWuhan 430070HubeiChina National Engineering Research Center of Fiber Optic Sensing Technology and Networks Wuhan University of TechnologyWuhan 430070HubeiChina Hubei Key Laboratory of Broadband Wireless Communication and Sensor Networks Wuhan 430070HubeiChina

Active control of terahertz(THz)waves is attracting tremendous attentions in terahertz communications and active photonic ***,due to its excellent photoelectric conversion performance and simple manufacturing process,has emerged as a promising candidate for optoelectronic ***,the exploration of perovskites in optically controlled THz modulators is still *** this work,the photoelectric properties and carrier dynamics of fa_(0.4)MA_(0.6)PbI_(3)perovskite films were investigated by optical pumped terahertz probe(OPTP)*** ultrafast carrier dynamics reveal that fa_(0.4)MA_(0.6)PbI_(3)thin film exhibits rapid switching and relaxation time within picosecond level,suggesting that fa_(0.4)MA_(0.6)PbI_(3)is an ideal candidate for active THz devices with ultrafast ***,as a proof of concept,a fa_(0.4)MA_(0.6)PbI_(3)-based metadevice with integrating plasma-induced transparency(PIT)effect was fabricated to achieve ultrafast modulation of THz *** experimental results demonstrated that the switching time of fa_(0.4)MA_(0.6)PbI_(3)-based THz modulator is near to 3.5 ps,and the threshold of optical pump is as low as 12.7μJ cm^(-2).The simulation results attribute the mechanism of ultrafast THz modulation to photo-induced free carriers in the fa_(0.4)MA_(0.6)PbI_(3)layer,which progressively shorten the capacitive gap of PIT *** study not only illuminates the potential of fa_(0.4)MA_(0.6)PbI_(3)in THz modulation,but also contributes to the field of ultrafast photonic devices.

关键词： Terahertz modulation Perovskites Metamaterials Plasmon-induced transparency

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定量核磁共振磷谱同时测定浓维磷糖浆中甘油磷酸钠和磷酸的含量

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分析化学 2024年第7期52卷 1020-1027页

作者：屠相土李俊雷虹徐玲萍曾茂法台州市食品药品检验研究院

建立了定量核磁共振磷谱法(31P-q NMR)同时测定浓维磷糖浆中α-甘油磷酸钠、β-甘油磷酸钠和磷酸含量的方法。考察了q NMR实验条件对测定结果的影响，选择六甲基磷酰三胺为内标、20%重水溶液（V/V）为溶剂，选择zgig脉冲序列、延迟时间3... 详细信息

建立了定量核磁共振磷谱法(31P-q NMR)同时测定浓维磷糖浆中α-甘油磷酸钠、β-甘油磷酸钠和磷酸含量的方法。考察了q NMR实验条件对测定结果的影响，选择六甲基磷酰三胺为内标、20%重水溶液（V/V）为溶剂，选择zgig脉冲序列、延迟时间30 s、扫描次数64次为实验条件，进行采样测试获取31P-q NMR谱，其中，六甲基磷酰三胺、α-甘油磷酸钠、β-甘油磷酸钠和磷酸的定量共振峰分别为δ 29.80、δ 0.69、δ 0.17和δ 0.03（供试品溶液p H≈4.8）。结果表明，31P-q NMR法测定α-甘油磷酸钠、β-甘油磷酸钠和磷酸的检出限分别为23.58、23.58和11.61μg/m L，定量限分别为78.60、78.60和38.70μg/m L，线性相关系数（R）均大于0.999，精密度小于0.6%，平均回收率为99.8%～103.2%，相对标准偏差（RSD）为0.41%～1.98%。本研究建立的31P-q NMR方法测定结果准确，稳定可靠。采用本方法测定了7批次不同厂家的浓维磷糖浆样品，其中，总磷量检测结果与比色法一致；甘油磷酸钠含量（α型与β型之和）偏低，约为标示量的82%；磷酸含量偏高。本方法操作简单、专属性强，适合作为浓维磷糖浆质量控制的方法。

关键词：定量核磁共振磷谱法浓维磷糖浆甘油磷酸钠磷酸

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A Spinor Approach to the SU(2) Clebsch-Gordan Coefficients

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Communications in Theoretical Physics 2019年第6期71卷 663-669页

作者： ling-Di yang fa-Min Chen Department of Physics Beijing Jiaotong University

We review the irreducible representation of an angular momentum vector operator constructed in terms of spinor algebra. We generalize the idea of spinor approach to study the coupling of the eigenstates of two independent angular momentum vector operators. Utilizing the spinor algebra, we are able to develop a simple way for calculating the SU(2) Clebsch-Gordan(CG) coefficients. The explicit expression for the SU(2) CG coefficients is worked out, and some simple physical examples are presented to illustrate the spinor approach.

关键词： Clebsch-Gordan coefficients spinors representations

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Multiple regression analysis of risk factors related to radiation pneumonitis

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World Journal of Clinical Cases 2023年第5期11卷 1040-1048页

作者： ling-ling Shi Jiang-Hua yang Hong-fa Yao Department of Radiology Huzhou Central HospitalAffiliated Central Hospital of Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects patients’quality of *** To carry out multiple regression analysis on the influencing factors of radiation *** Records of 234 patients receiving chest radiotherapy in Huzhou Central Hospital(Huzhou,Zhejiang Province,China)from January 2018 to February 2021,and the patients were divided into either a study group or a control group based on the presence of radiation pneumonitis or *** them,93 patients with radiation pneumonitis were included in the study group and 141 without radiation pneumonitis were included in the control *** characteristics,and radiation and imaging examination data of the two groups were collected and *** to the statistical significance observed,multiple regression analysis was performed on age,tumor type,chemotherapy history,forced vital capacity(FVC),forced expiratory volume in the first second(FEV1),carbon monoxide diffusion volume(DLCO),FEV1/FVC ratio,planned target area(PTV),mean lung dose(MLD),total number of radiation fields,percentage of lung tissue in total lung volume(vdose),probability of normal tissue complications(NTCP),and other *** The proportions of patients aged≥60 years and those with the diagnosis of lung cancer and a history of chemotherapy in the study group were higher than those in the control group(Pfactors for radiation *** We have identified patient age,type of lung cancer,history of chemotherapy,lung function,and radiotherapy pa

关键词： Radiation pneumonitis Influencing factors Radiotherapy Multiple regression analysis

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长期放牧和氮添加对黄土高原典型草原长芒草种群生长的影响

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植物生态学报 2024年第3期48卷 317-330页

作者：黄玲王榛马泽杨发林李岚 SEREKPAYEV Nurlan NOGAYEV Adilbek 侯扶江草种创新与草地农业生态系统全国重点实验室农业农村部草牧业创新重点实验室国家林业草原西北退化草原生态修复与利用工程技术研究中心兰州大学草地农业科技学院兰州730020 宁夏回族自治区草原工作站银川750002 Department of Agriculture and Plant Growing Saken Seifullin Kazakh Agrotechnical UniversityAstana 010011Kazakhstan

种群是草原生态系统结构、功能形成和发展的基础。然而,长期放牧伴随着全球气候变化深刻影响着种群的生长和繁殖。长芒草(Stipa bungeana)是黄土高原典型草原的优势种,具有较高的生态和经济价值。该研究依托黄土高原典型草原长期滩羊轮... 详细信息

种群是草原生态系统结构、功能形成和发展的基础。然而,长期放牧伴随着全球气候变化深刻影响着种群的生长和繁殖。长芒草(Stipa bungeana)是黄土高原典型草原的优势种,具有较高的生态和经济价值。该研究依托黄土高原典型草原长期滩羊轮牧实验平台,采用完全随机的裂区实验设计,以放牧率(0、2.7、5.3、8.7 sheep·hm^(-2))作为主因子,氮添加水平(0、5、10、20 g·m^(-2))作为副因子,探究放牧、氮添加及其交互作用对长芒草的形态性状、地上生物量及其占群落生物量比例的作用。结果表明:随放牧率的增加,长芒草的株高、冠幅直径、分蘖密度、实生苗密度、地上生物量和生物量占比呈“单峰”曲线变化趋势,种群密度降低。而氮添加增加长芒草的株高、冠幅直径、生殖枝密度、分蘖密度、地上生物量和生物量占比;实生苗密度随氮添加的增加呈先增后减的趋势。相比氮添加,放牧对长芒草地上生物量和生物量占比的总效应小,放牧对地上生物量有直接的负效应,并通过调控分蘖密度、种群密度及地上生物量影响其生物量占比;氮添加不仅对地上生物量有直接的积极效应,还通过株高、生殖枝密度对地上生物量有间接的正效应,同时通过调控种群密度、冠幅直径、分蘖密度和生殖枝密度影响生物量占比。总体上,氮添加增加长芒草的冠幅直径和生殖枝密度(相比株高和分蘖密度),放牧增加实生苗密度(相比种群密度),而放牧和氮添加的交互作用显著影响生殖枝密度。放牧率为4.10和5.29 sheep·hm^(-2)时长芒草具有最大地上生物量及其群落占比。上述结果表明放牧和氮添加通过影响长芒草种群的形态特征来调控其地上生物量和群落地位。

关键词：放牧氮添加种群形态性状地上生物量群落地位

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Synthesis of polypiperazine-amide thin-film membrane on PPESK hollow fiber UF membrane

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Chinese Chemical Letters 2007年第8期18卷 966-968页

作者： fa Jie yang Da ling yang Shou Hai Zhang Xi Gao Jian Department of Polymer Science and Materials Dalian University of TechnologyLiaoning High Performance Resin Engineering Research Center Dalian 116012 China

A new interfacial polymerization （IP） procedure is developed in order to synthesize polypiperazine-amide thin-film membrane on the inner surface of poly（phthalazinone ether sulfone ketone）（PPESK） hollow fiber ultrafiltration （UF） membrane. A hollow fiber composite membrane with good performance was prepared and studied by PT-IR and scanning electron microscopy.

关键词： Poly(phthalazinone ether sulfone ketone) Hollow fiber Nanofiltration membrane Composite membrane Interfacial polymerization

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Automatic Identification of Clear-Air Echoes Based on Millimeter-wave Cloud Radar Measurements

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Advances in Atmospheric Sciences 2020年第8期37卷 912-924页

作者： ling yang Yun WANG Zhongke WANG Qian yang Xingang faN fa TAO Xiaoqiong ZHEN Zhipeng yang Electronic Engineering College Chengdu University of Information TechnologyChengdu 610225China Information Security Engineering College Chengdu University of Information TechnologyChengdu 610225China Department of Geography and Geology Western Kentucky UniversityBowling GreenKY 42101USA Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China CMA Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing210044China Meteorological Observation Centre CMABeijing 100081China

Millimeter-wave cloud radar(MMCR)provides the capability of detecting the features of micro particles inside clouds and describing the internal microphysical structure of the ***,MMCR has been widely applied in cloud ***,due to the influence of non-meteorological factors such as insects,the cloud observations are often contaminated by non-meteorological echoes in the clear air,known as clear-air *** is of great significance to automatically identify the clear-air echoes in order to extract effective meteorological information from the complex weather *** characteristics of clear-air echoes are studied here by combining data from four devices:an MMCR,a laser-ceilometer,an L-band radiosonde,and an all-sky *** addition,a new algorithm,which includes feature extraction,feature selection,and classification,is proposed to achieve the automatic identification of clear-air *** results show that the recognition algorithm is fairly satisfied in both simple and complex weather *** recognition accuracy can reach up to 95.86%for the simple cases when cloud echoes and clear-air echoes are separate,and 88.38%for the complicated cases when low cloud echoes and clear-air echoes are mixed.

关键词： millimeter-wave cloud radar clear-air echoes neural network laser ceilometer all-sky camera feature extraction feature selection

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Endovascular graft exclusion for gastroduodenal artery remnant hemorrhage after pancreaticoduodenectomy

Endovascular graft exclusion for gastroduodenal artery remna...

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中国抗癌协会胆道肿瘤专业委员会成立大会暨第一届全国胆道肿瘤学术会议

作者： Liu Chen,Li Bin,Luo Xiang-ji,Yu Yong,Fen Fei-ling,yang Ye-fa,Chen Dong,LongXing-an, Cheng Hong-yan,Jiang Xiao-qing Department of Biliary duct surgeryⅠ Depatment of Interventional treatment Depatment of Radiology Eastern hepatic biliary hospital,Secondary military medicine university

Background:Intra-abdominal aortic bleeding after pancreatoduodenectomy(PD) is a fatal complication which leads to high mortality rate in the event of dangerous *** options include reoperation or endovascular minimally invasive techniques such as embolization *** present article describes our experiences with endovascular graft exclusion(EVGE) by implantation of membrane-covered stent grafts. Methods:The findings of two patients with gastroduodenal artery remnant rupture and hemorrhage are *** patients were treated with placement of membrane-covered stent grafts in the common hepatic artery(EVGE).The patients’medical records,radiological reports,and images were retrospectively reviewed. Technical success was defined as immediate cessation of *** success was defined as hemodynamic stability. Results:Two stent grafts were implanted in the common hepatic artery,*** patient developed recurrent hemorrhages of the common hepatic artery,Technical and clinical success was achieved at every *** were no major complications in two patients after EVGE. Conclusions:Endovascular graft exclusion(EVGE) using membrane-covered stent grafts is an effective and safe procedure for the treatment of intra-abdominal arterial bleeding after pancreatoduodenectomy(PD) The technique is a promising alternative to standard procedures such as surgical repair or embolization.

关键词： pancreatoduodenectomy pancreatic fistula intra-abdominal aortic bleeding endovascular graft exclusion membrane-covered stent grafts

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美国卓越数学与科学教师特质研究

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数学教育学报 2024年第4期33卷 73-77,102页

作者：姚一玲贾随军蔡金法杭州师范大学中国教育现代化研究院浙江杭州311121 浙江外国语学院浙江杭州310023 特拉华大学数学系纽瓦克19716

教师质量是有效教学的关键,揭示卓越教师的专业特质,能够为普通教师的专业发展提供重要依据.研究基于美国卓越数学与科学教学总统奖评选标准,对获奖教师的专业特质进行分析,主要聚焦于卓越数学与科学教师在职前训练、职后发展、课堂教学... 详细信息

教师质量是有效教学的关键,揭示卓越教师的专业特质,能够为普通教师的专业发展提供重要依据.研究基于美国卓越数学与科学教学总统奖评选标准,对获奖教师的专业特质进行分析,主要聚焦于卓越数学与科学教师在职前训练、职后发展、课堂教学3方面的具体表现.分析表明:卓越数学与科学教师比普通教师会修读更多学科专业课程,有更好的教学准备,参与更多专业发展活动,更倾向于主动运用新的和灵活的教学方法,对学生的评价手段也更加多元和开放,能够不断反思和学习.

关键词：卓越教师数学教师科学教师专业特质

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延迟交配对皂角豆象寿命及繁殖的影响

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应用昆虫学报 2024年第2期61卷 271-278页

作者：黄成艳张升廖俊罗康李猷武承旭徐芳玲杨茂发贵州大学林学院兴仁市农业农村局贵州省植保植检站福建农林大学植物保护学院贵州大学昆虫研究所贵州山地农业病虫害重点实验室贵州大学烟草学院

【目的】为了明确延迟交配对皂角豆象Megabruchidius dorsalis (fahraeus)(Coleoptera:Bruchinae)寿命及繁殖的影响。【方法】在室内条件下，分别对初羽化未交配的皂角豆象雌雄虫、雄虫、雌虫分别延迟1-7 d后配对饲养，研究延迟交配对... 详细信息

【目的】为了明确延迟交配对皂角豆象Megabruchidius dorsalis (fahraeus)(Coleoptera:Bruchinae)寿命及繁殖的影响。【方法】在室内条件下，分别对初羽化未交配的皂角豆象雌雄虫、雄虫、雌虫分别延迟1-7 d后配对饲养，研究延迟交配对该虫产卵前期、产卵期、产卵量、卵孵化率、子代性比及雌、雄成虫寿命等参数的影响。【结果】雌、雄同时延迟交配和雌虫延迟交配显著延长雌虫寿命（P0.05）。在3种延迟交配模式下，延迟交配对皂角豆象产卵期、产卵次数、产卵量和孵化率均有不利影响（皮尔森相关系数r0.05），其中皂角豆象雌虫在延迟交配1和2 d时的产卵量最高，在延迟交配6和7 d时的产卵量明显下降；雌、雄同时延迟交配和雄虫延迟交配显著降低卵的孵化率（P<0.05）。【结论】延迟交配会降低皂角豆象的繁殖潜力，结果将为深入探讨田间使用信息素迷向法防治皂角豆象提供依据。

关键词：皂角豆象延迟交配寿命繁殖产卵

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