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Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc minh Tran Kim Anh Nguyen Duy Hung Pham Thi minh Chau Nguyen Thi Quy hai Ho Van Tuyen Vu Thi Thai ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

高校校区空间布局与校企协同创新——基于专精特新“小巨人”企业的微观经验证据

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高等教育研究 2024年第3期45卷 42-53页

作者：张文杰哈巍北京大学教育经济研究所北京100871

基于9200余家专精特新“小巨人”企业相关数据,量化评估高校校区空间布局对校企协同创新的影响发现,“小巨人”企业周边15公里范围内高校校区数量对校企联合申请并获授权专利的数量、校企合作广度与深度均有显著正向影响;从企业维度看,... 详细信息

基于9200余家专精特新“小巨人”企业相关数据,量化评估高校校区空间布局对校企协同创新的影响发现,“小巨人”企业周边15公里范围内高校校区数量对校企联合申请并获授权专利的数量、校企合作广度与深度均有显著正向影响;从企业维度看,显著促进了高校与高技术产业企业的发明专利研发合作,以及与非高技术产业企业、成长期企业的非发明专利研发合作;从高校维度看,这种影响主要来自本科高校尤其是高水平研究型高校;此外,校企协同创新随二者间距离增大而衰减。高校校区布局对企业持有的非校企联合申请专利数量也有显著影响,且这种间接效应大于以上直接效应。今后高校校区空间布局调整需综合考虑高校与企业的适配度,同时重点关注高水平研究型高校校区布局,助力深化校企协同创新。

关键词：校企协同创新高校校区空间布局 “小巨人”企业专利

Rainfall Threshold Analysis and Bayesian Probability Method for Landslide Initiation Based on Landslides and Rainfall Events in the Past

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Open Journal of Geology 2018年第7期8卷 674-696页

作者： hien minh Do Kun Long Yin Faculty of Engineering China University of Geosciences (Wuhan) Wuhan China Vietnam Institute of Geosciences and Mineral Resources Hanoi Vietnam

In this paper a rainfall threshold and a Bayesian probability model are presented for the landslide occurrence of shallow landslides in ha Giang city and the surroundings, Vietnam. The model requires the data on daily rainfall combined with the actual dates of landslide occurrences. Careful study on the database is a prerequisite for the paper. For this reason, selecting the input data was carried out carefully to ensure the reliable results of the study. The daily rainfall data covering a time span of 57 years was collected from a unique rain gauge station of National Centre for Hydro-meteorological Forecasting of Vietnam (from 1957 to 2013) and a landslide database with some landslides (37 of total of 245 landslides) that containing dates of occurrence, was prepared from historical records for the period 1989 to 2013. Rainfall thresholds were generated for the study area based on the relationship between daily and antecedent rainfall of the landslide events. The results shows that 3-day antecedent rainfall (with the rainfall threshold was established: RT = 40.8 −0.201R3ad) gives the best fit for the existing landslides in the landslide database. The Bayesian probability model for one-dimensional case was established based on 26 landslides for the period 1989 to 2009, daily rainfall data with the same time and the values of probability varies from 0.03 to 0.44. Next, the Bayesian probability model for two-dimensional case was generated based on 11 landslides, rainfall intensity and duration in three months (May, June and July) of 2013 and the values of probability ranges from 0.08 to 0.67, and computed values of conditional landslide probability P(A|B) from two-dimensional case of Bayesian approach are clearly controlled by rainfall intensity > 40 mm with rainfall duration > 0.3 day.

关键词： Rainfall Threshold Antecedent Rainfall Bayesian Probability ha Giang

Revealing efficient catalytic performance of N-CuO_(x) for aerobic oxidative coupling of aliphatic alkynes:A Langmuir-Hinshelwood reaction mechanism

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Nano Research 2022年第7期15卷 6076-6083页

作者： Jun Tang Bowen Jiao Wei Chen Fei Ruan Fengfeng Li Peixin Cui Chao Wan minh Ngoc ha Van Noi Nguyen Qingping Ke College of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Sciencethe Chinese Academy of SciencesNanjing 210008China VNU Key Laboratory of Advanced Material for Green Growth VNU University of ScienceVietnam National UniversityHanoi 100000Vietnam

O_(x)idative couplings of aliphatic alkynes are crucial for the production of naturally occurring 1,*** we report the novel approach for effective synthesis of unsaturated coordinated N doped copper oxides(N-CuO_(x))catalyst,and uncover that N-CuO_(x) catalyst as an additive-free and cost-effective heterogeneous catalyst has highly catalytic performance for directly oxidative coupling of aliphatic *** key to achieve efficient oxidative coupling of aliphatic alkynes is the synergistic effect of N species and uncoordinated O/Cu species caused by N dopants,which undergoes the Langmuir–Hinshelwood reaction *** N-CuO_(x) catalyst displays~89.1%yield for hexadeca-7,9-diyne under mild conditions and stable reusability(5 cycles),showing significant advances compared with the traditionally copper *** findings highlight the heteroatom dopants that provide a new methodology for designing efficient copper catalysts in synthesis of naturally occurring 1,3-diynes.

关键词： N doped copper oxides(N-CuO_(x)) straight chain alkynes homo-coupling additive-free 1,3-diynes

为什么是黑色古典:以杜波依斯的古典神话诠释为例

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英美文学研究论丛 2024年第1期 214-226页

作者：哈旭娴南京师范大学文学院

黑色古典是非裔美国文学创作的重要特点之一。古典之于非裔美国人的意义远超于文学审美层面,一方面,它证明了黑人与古代的确实关联,从而动摇种族奴隶制存在的基础;另一方面,古典一度被黑人群体构建为一种文化资本,古典学习是非裔美国人... 详细信息

黑色古典是非裔美国文学创作的重要特点之一。古典之于非裔美国人的意义远超于文学审美层面,一方面,它证明了黑人与古代的确实关联,从而动摇种族奴隶制存在的基础;另一方面,古典一度被黑人群体构建为一种文化资本,古典学习是非裔美国人获取公民身份、提升民族品格、塑造民族领袖的重要途径。以杜波依斯的古典神话诠释为例,可以发现在非裔美国人的文学创作中,古希腊-罗马神话世界与当代社会的结合形成了文化融合,在融合中原型神话被重新塑造成一种根植于黑人经验,积极抵制种族主义并建构黑人身份的新神话。

关键词：黑色古典文化资本黑人经验古典诠释

Effects of low energy (160 keV) X-ray on microbial inactivation,sprouting inhibition and genetic variation in potato

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Food Bioscience 2022年第3期47卷 262-270页

作者： Nguyen An Son Nguyen Thi Nguyet ha Nguyen Thi minh Sang Le Doan Dinh Duc Le Ngoc Trieu Faculty of Physic and Nuclear Engineering Da Lat UniversityViet Nam Dalat Vocational Training College Viet Nam Faculty of Biology Da Lat UniversityViet Nam

The effects of low energy X-ray irradiation on microbial inactivation,sprouting inhibition and genetic variation were *** was an inverse correlation between the exposure dose in range of 0 Gy–5000 Gy and the survival rate of *** dose of 1000 Gy seemed to be suitable for inactivation of microorganisms because the respective survival rate is relatively low (0.59%).Dose rate of 13.87 Gy/min was the most appropriate to inactivate the microorganisms,with the survival rate of 0.37%.Applying the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,there was a significant sprouting inhibition of irradiated potatoes compared to the control for six months *** effect of irradiation dose (100–1200 Gy) and dose rate (8.63–19.62 Gy/min) on genetic variation of the irradiated samples was assessed by DNA fingerprints induced from using three molecular techniques including Random Amplified Polymorphic DNA (RAPD),Start Codon Targeted Polymorphism (SCoT) and CAAT box – derived polymorphism (CBDP).At the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,the level of genetic variation was relatively low (4.85%).Thus,this treatment is a suitable condition of irradiation for potato treatment with the purpose of preservation.

关键词： Dose Dose rate Low energy X-ray Microbial inactivation Potato

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菲莉斯·惠特利的文化适应与文学越界

太原学院学报（社会科学版） 2024年第6期25卷 100-108,F0002页

作者：哈旭娴南京师范大学文学院江苏南京210023

菲莉斯·惠特利是18世纪美国重要的黑人女诗人,在种族主义盛行的时代,她的出现有偶然性因素,但又不能完全看作是一起偶然的文学事件。美国独立革命前后,非洲人的“美国化”成为一股不可阻挡的历史趋势,惠特利是其中的一员。她在新英格... 详细信息

菲莉斯·惠特利是18世纪美国重要的黑人女诗人,在种族主义盛行的时代,她的出现有偶然性因素,但又不能完全看作是一起偶然的文学事件。美国独立革命前后,非洲人的“美国化”成为一股不可阻挡的历史趋势,惠特利是其中的一员。她在新英格兰地区获得文学声望是她主动性文化适应的结果。她令自己诗歌合法化的策略之一是以皈依的非洲人身份,用最虔诚的清教徒方式,对核心精神和道德现实作经验性阐释。惠特利运用挽歌、史诗等符合美国社会认可的形式使自己获得精英阶层的授权,并建立自己的文学权威性,同时她能够在诗歌世界中协调好当时世界主义与地方主义之间的矛盾与竞争。但是诗人的文化适应不应看作简单的模仿行为,在她创造性运用传统文学叙事形式之下潜藏着僭越的野心。

关键词：菲莉斯·惠特利文化适应新英格兰越界

汉语非流畅性失语症患者特指疑问句句法障碍特征

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听力学及言语疾病杂志 2024年

作者：康晓茜张宗云郎晓赵纹笙 Kim ha Kyung 王勇丽黄昭鸣华东师范大学教育学部康复科学系山东省耳鼻喉医院

目的研究汉语非流畅性失语症患者特指疑问句理解与表达的句法障碍特征。方法以句-图匹配、诱导-复述的形式对25例汉语非流畅性失语症患者和25例正常人进行理解和表达能力测试,比较两组结果差异,分析句式、提问对象和疑问词相关句法障... 详细信息

目的研究汉语非流畅性失语症患者特指疑问句理解与表达的句法障碍特征。方法以句-图匹配、诱导-复述的形式对25例汉语非流畅性失语症患者和25例正常人进行理解和表达能力测试,比较两组结果差异,分析句式、提问对象和疑问词相关句法障碍特点。结果非流畅性失语症患者特指疑问句理解和表达能力均受损,各种类型特指疑问句的正确率均显著低于对照组(P主语伪分裂疑问句和被动疑问句;各种类型的特指疑问句产出正确率均低于对照组,“谁”主动疑问句、“什么”宾语主动疑问句的正确率无显著性差异(P>0.05),其他类型均存在显著性差异(P伪分裂疑问句和被动疑问句。结论汉语非流畅性失语症患者特指疑问句理解和表达受损模式基本相似。句法结构方面主要影响因素包括提问对象(主宾)和句式类型,有wh-成分移位、非规范顺序的句子障碍更明显。

关键词：非流畅性失语症特指疑问句理解表达句法

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油水环状流截面相含率超声衰减法测量

化工进展 2024年第2期43卷 768-780页

作者：哈雯杨杨唐雨曹頔张超杨斌上海理工大学能源与动力工程学院上海200093 上海市动力工程多相流动与传热重点实验室上海200093

为研究超声衰减法测量油水环状流截面相含率问题,采用COMSOL仿真软件建立油水环状流模型,选择超声传感器结构尺寸6mm和超声发射频率1MHz进行研究,通过分析油水环状流超声衰减特性,确定油水环状流的超声衰减系数与截面含油率关系,并获得... 详细信息

为研究超声衰减法测量油水环状流截面相含率问题,采用COMSOL仿真软件建立油水环状流模型,选择超声传感器结构尺寸6mm和超声发射频率1MHz进行研究,通过分析油水环状流超声衰减特性,确定油水环状流的超声衰减系数与截面含油率关系,并获得线性关系的测量范围。在此基础上进一步研究非理想环状流相关参数对超声衰减特性的影响,并提出将非理想环状流差别阈限用于定量评价非理想环状流因素对于理想环状流超声衰减法的影响,获得非理想环状流差别阈限±10%以内同心度和椭圆度的变化范围。最后开展了油水环状流静态验证实验。研究结果表明:油水环状流截面相含率在5%~30%范围内,与超声衰减系数呈线性关系,同时在此范围内,非理想环状流差别阈限在±10%以内的同心度和椭圆度变化范围分别为0.75~1和0~5%,实验结果和仿真模拟结果具有近似的上升趋势。

关键词：两相流油水环状流超声衰减法数值模拟相含率

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