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Synthesis and applications of mesoporous Cu-Zn-Al_2O_3 catalyst for dehydrogenation of 2-butanol

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Journal of Natural Gas Chemistry 2009年第2期18卷 179-182页

作者： Deren Fang Wanzhong Ren Zhongmin Liu xiufeng xu Lei xu Hongying Lǔ Weiping Liao Huimin Zhang Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China Institute of Applied Catalysis of Yantai University Yantai 264005 Shandong China

A series of mesoporous Cu-Zn-Al2O3 materials have been synthesized at ambient temperature and their structure was characterized by XRD, N2 physical adsorption and TPR techniques. Their catalytic applications for the dehydrogenation of 2-butanol to methyl ethyl ketone （MEK） were evaluated in a fixed-bed flow reactor at atmospheric pressure. It is demonstrated from the XRD patterns that both the as-synthesized samples and calcined samples have the typical XRD patterns of meso-structured materials and the results of N20 chemical adsorption showed that Cu was embedded in the framework of the mesoporous materials and homogeneously dispersed in the mesoporous Cu-Zn-Al2O3 materials. The catalytic activity of 2-butanol dehydrogenation was varied in the order of CZA（10）〈 CZA（CP）〈 CZA（20）〈 CZA（30）; while the selectivity of MEK was increased in the order of CZA（CP）〈 CZA（10）〈 CZA（20）〈CZA（30）.

关键词： Cu-Zn-Al2O3 mesoporous materials dehydrogenation of 2-butanol catalyst

首次发病未服药成年抑郁症患者大脑皮质厚度变化的Meta分析

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中华精神科杂志 2024年第8期57卷 512-519页

作者：平亮亮孙珊周聪和梦鑫阙建宇郑琪沈宗霖许秀峰程宇琪昆明医科大学第一附属医院精神科昆明650032 厦门市仙岳医院厦门361000 济宁医学院精神卫生学院济宁272000 上海交通大学医学院附属仁济医院心理医学科上海200127

目的通过Meta分析探讨首次发病未服药抑郁症患者大脑灰质皮质厚度的变化特征。方法以"depression"或"depressive disorder"或"unipolar depression"以及"cortical thickness"或"thickness"为关键词,检索PubMed、Web of Science数据库自建库开始截至2023年7月23日发表的与抑郁症大脑皮质厚度变化有关的基于全脑皮质顶点分析的研究。采用标记差异映射分析(signed differential mapping,SDM)软件进行基于全脑体素的数据分析,通过Meta回归分析探讨疾病严重程度对抑郁症皮质厚度的影响,并检验异质性及评估发表偏倚。结果共纳入8项研究,包括417例首次发病未服药抑郁症患者和409名健康对照者。与健康对照者相比,首次发病未服药抑郁症患者在辅助运动区(Z=-2.471)和中央沟盖区(Z=-2.190)等多个脑区呈现皮质厚度降低(均P<0.0005)。进一步回归分析发现首次发病未服药抑郁症患者的疾病严重程度与辅助运动区(Z=2.265,P<0.0005)和右侧中央沟盖区(Z=1.560,P<0.0005)的皮质厚度变化呈正相关,平均疾病持续时间与右侧额下回岛盖部皮质厚度变化呈正相关(Z=1.922,P<0.0005),与右侧中扣带回的皮质厚度变化呈负相关(Z=-3.035,P<0.0005)。结论首次发病未服药抑郁症患者在疾病早期即出现辅助运动区以及岛盖区的皮质厚度降低,并且这种皮质变化与疾病严重程度和病程均有关。

关键词：抑郁症首次发病皮质厚度 Meta分析

Effective modification of MgO with surface transition metal oxides for NF_3 decomposition

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Journal of Natural Gas Chemistry 2011年第5期20卷 457-459页

作者： Yanan Wang xiufeng xu PeiSheng Hongguang Li Tingting Wang Youfen Huang Fangshu Liu School of Chemistry and Chemical Engineering Yantai University Yantai 264005 Shandong China

NF3 decomposition over transition metal oxides coated MgO reagents in the absence of water is investigated. The results show that NF3 can be decomposed completely over pure MgO but the time of NF3 steady full conversion kept as short as 80 min, while the reactivities of coated MgO reagents were remarkably enhanced by transition metal oxides, for example the time of NF3 complete conversion over 12%Fe/MgO extended to 380 min. It is suggested that not only an increase in surface area but also a significant enhancement in the fluorination of MgO substrate caused by the surface transition metal oxides result in an improved reactivity of coated MgO reagents for NF3 decomposition.

关键词： NF3 decomposition defluorinated reagents transition metal oxides coated MgO reactivity

An automatic gain adjustment Campbell integrator for neutron flux detection in ITER

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Nuclear Science and Techniques 2012年第2期23卷 114-117页

作者： CAO Hongrui LI Shiping xu xiufeng TANG Shibiao YANG Jinwei YANG Qingwei YIN Zejie State Key Lab Particle Detect&Elect University of Science and Technology of ChinaHefei 230026China Southwestern Institute of Physics Chengdu 610041China

Neutron Flux Monitor, a key diagnostic system in International Thermonuclear Experimental Reactor, may provide for reading a series of important parameters in fusion reaction process. We designed an important part of its main electronic system - Automatic Gain Adjustment Campbell Integrator (AGACI), expanding the detecting neutron counting rate of 104-108 cps (counts per second). The total gain of AGACI in five files is divided into 1, 10, 100, 1000, and 10 000 times, and can be automatically adjusted. The linear correlation coefficient (R) is more than 0.9999 in AGACI working range.

关键词：增益调整中子通量 ITER 贝尔检测国际热核实验反应堆积分线性相关系数

Design and Implementation of Urban-rural Power Grid Dispatching Fault Diagnosis Expert System

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International Journal of Technology Management 2013年第2期 118-121页

作者： xu xiufeng Guangxi Power-grid Wuxuan Power Supply Company

The paper designs the urban-rural power grid dispatching fault diagnosis expert system which acquires fault information by SCADA system of automatic system of urban-rural power grid, and uses artificial intellegence method to analyze fault information and make fault diagnosis. The paper implements the core part of the fault expert system the design of knowledge base and fault inference engine.

关键词： urban-rural power grid fault diagnosis expert system

Multicolor emission from lanthanide ions doped lead-free Cs_(3)Sb_(2)Cl_(9) perovskite nanocrystals

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Journal of Rare Earths 2024年第5期42卷 940-946,I0005页

作者： He Shao Lifang Li xiufeng Wu Lin xu Biao Dong Donglei Zhou xue Bai Hongwei Song State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials College of Materials Science and EngineeringNanjing University of Posts&TelecommunicationsNanjing210023China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin UniversityChangchun130012China

The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still ***,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current *** this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite *** from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was *** on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped *** addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,***,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).

关键词： Perovskite nanocrystals Lead free Lanthanide ions Energy transfer White light emitting device Rare earths

Evidence of compliance with and effectiveness of guidelines for noninvasive prenatal testing in China:a retrospective study of 189,809 cases

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Science China(Life Sciences) 2020年第3期63卷 319-328页

作者： Chan Tian Tao Deng Xiuhuang Zhu Chen Gong Yangyu Zhao Yuan Wei Rong Li xiufeng xu Miaonan He Zhiwei Zhang Jing Cheng Mol BenWillem Jie Qiao Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Key Laboratory of Assisted Reproduction(Peking University) Ministry of EducationBeijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Beijing CapitalBio Medical Laboratory Beijing 101111China Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China National Engineering Research Center for Beijing Biochip Technology Beijing 102206China Department of Biomedical Engineering Tsinghua University School of MedicineBeijing 100084China Robinson Institute School of Paediatrics and Reproductive HealthUniversity of AdelaideSAAustralia Beijing Advanced Innovation Center for Genomic Beijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China

In China,the medical guidelines recommend performing noninvasive prenatal testing(NIPT)with caution for pregnant women aged 35 years or ***,the Mother and Child Health Care Law suggests that all primiparous women whose age is older than 35 years undergo prenatal *** two inconsistent suggestions/recommendations have made obstetricians confused about whether to offer NIPT to these older pregnant *** face this issue and find out the solution we performed a retrospective study of 189,809 NIPT samples collected from 28 provincial-leveled administrative units in *** 1,564 women with high-risk pregnancies who underwent NIPT,459(29.3%)did not participate in *** compound sensitivity and specificity of NIPT for trisomies 21,18 and 13 detection was 99.1%(95%CI,98.0%–99.6%)and 99.9%(95%CI,98.8%–99.9%),*** secundiparous women,NIPT showed high sensitivity and specificity similar to that in primiparous *** observed risk for trisomies 21 and 18 significantly increased when the maternal age was 39 and *** the publication of the current NIPT policy,the follow-up rate at our center was 97.9%;however,a large number of women are not in maternal and infant care networks nationwide,and that makes the follow-up rate outside our center relatively *** study shows that to balance the prevention of major aneuploidies and the limited resources for prenatal diagnosis,the cut-off age of 35 for invasive prenatal diagnosis might be *** the NIPT guidelines are well written,how to practice it effectively,especially in less industrialized areas,is worth discussing.

关键词： NIPT risk for trisomy NIPT policy in China prenatal diagnosis maternal age

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氯氟烃分解反应催化剂的研究进展

石油化工 2005年第6期34卷 591-594页

作者：徐秀峰潘燕飞烟台大学应用催化研究所山东烟台264005 烟台大学分析中心山东烟台264005

对有效消除氯氟烃的催化反应法(氯氟烃的加氢脱氯和催化分解)进行了评述。重点对近年来报道的用于氯氟烃加氢脱氯的负载型贵金属催化剂和用于氯氟烃催化分解的金属氧化物、SO42-促进型金属氧化物、沸石分子筛、负载型贵金属、磷酸盐等... 详细信息

对有效消除氯氟烃的催化反应法(氯氟烃的加氢脱氯和催化分解)进行了评述。重点对近年来报道的用于氯氟烃加氢脱氯的负载型贵金属催化剂和用于氯氟烃催化分解的金属氧化物、SO42-促进型金属氧化物、沸石分子筛、负载型贵金属、磷酸盐等催化剂进行了总结和比较,认为磷酸盐A lPO4有望成为催化活性高、稳定性强的氯氟烃分解催化剂。

关键词：氯氟烃催化分解催化剂磷酸盐

无水条件下卤代烃在金属氧化物上裂解反应的研究进展

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石油化工 2008年第11期37卷 1218-1222页

作者：徐秀峰潘燕飞烟台大学应用催化研究所山东烟台264005

对消除工业过程排放的卤代烃(CCl_4、氯氟烃和全氟烃)废气的裂解吸附法进行了综述。重点对近年来报道的用于裂解CCl_4,CCl_3F,CCl_2F_2的 CaO 和 MgO 等碱上金属氧化物吸附剂、裂解 CF_4 f的γ-Al_2O_3吸附剂进行了总结和比较。改性γ-A... 详细信息

对消除工业过程排放的卤代烃(CCl_4、氯氟烃和全氟烃)废气的裂解吸附法进行了综述。重点对近年来报道的用于裂解CCl_4,CCl_3F,CCl_2F_2的 CaO 和 MgO 等碱上金属氧化物吸附剂、裂解 CF_4 f的γ-Al_2O_3吸附剂进行了总结和比较。改性γ-Al_2O_3裂解吸附 CF_4的稳定性较好,但 CF_4转化率不高,应改进γ-Al_2O_3的制备方法,增加比表面积和孔体积以提高其活性和氟容量。

关键词：卤代烃裂解吸附金属氧化物吸附剂