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以赛促教:大学生化学科普实验作品设计——以《“海绵城市”——自循环水体过滤系统》为例

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黄山学院学报 2024年第3期26卷 90-95页

作者：王澍刘软惠樊欣宇马金龙兰艳素黄山学院化学化工学院安徽黄山245041

大学生进行化学实验的意义在于促进大学生对化学知识的深入理解和对应用能力的培养。自循环水体过滤系统是基于海绵城市设计理念自主设计、制作的水体净化装置。通过采用定量评价污水处理材料性能的方法,直观展示了城市污水处理成果的... 详细信息

大学生进行化学实验的意义在于促进大学生对化学知识的深入理解和对应用能力的培养。自循环水体过滤系统是基于海绵城市设计理念自主设计、制作的水体净化装置。通过采用定量评价污水处理材料性能的方法,直观展示了城市污水处理成果的有效性,促进科普参加者理解城市污水处理的重要意义,使海绵城市设计理念深入人心。该实验装置可重复拆卸组装,检测设备便携,可在校园及各类场馆中展示,实验过程科学严谨,结果具有说服力。另外实验操作简便,便于实现与科普参加者的个性互动,能激发科普参加者的兴趣,具有良好的科普效果。

关键词：海绵城市污水处理滴滤盒

Three new alkaloids isolated from the stem tuber of Pinellia pedatisecta

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Chinese Journal of Natural Medicines 2018年第2期16卷 139-142页

作者： DU Jing DING Jie MU Zhen-Qiang GUAN shu-Hong CHENG Chun-Ru liu Xuan GUO De-An School of Chemical Engineering Institute of Pharmaceutical Engineering Technology and Application Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education Sichuan University of Science & Engineering Shanghai Institute of Materia Medica Chinese Academy of Sciences Institute of Interdisciplinary Integrative Biomedical Research Shanghai University of Traditional Chinese Medicine

The present study was designed to determine the chemical constituents of the stem tuber of Pinellia pedatisecta. The chemical constituents were isolated and purified by various chromatographic techniques, and their structures were elucidated on the basis of physicochemical properties and spectral data. Three new alkaloids(compounds 1, 2, and 3) were obtained and identified as 9-((5-methoxypyridin-2-yl)methyl)-9 H-purin-6-amine(1), 4-(2-(2, 5-dioxopyrrolidin-1-yl)ethyl)phenyl acetate(2), and N-(9-((5-methoxypyridin-2-yl)methyl)-9 H-purin-6-yl)acetamide(3). These compounds were evaluated for their cytotoxicity against human cervical cancer He La cells. Compounds 1 and 3 significantly inhibited the proliferation of He La cells with IC_(50) values being 3.02 ± 0.54 and 7.16 ± 0.62 μmol·L^(-1), respectively.

关键词： Pinellia pedatisecta Alkaloids Structure identification Anti-tumor

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寒冷地区航站楼交通枢纽冬季室内风环境研究

建筑技术 2024年第2期55卷 231-235页

作者：张刘英袁战旗汪道先何栋王俊陈洁西安咸阳国际机场股份有限公司陕西咸阳712000

应用绿色节能技术对公共建筑进行改造,降低公共建筑的碳排放并提升其室内风环境水平是目前亟须解决的问题。在冬季,对西安咸阳国际机场T3航站楼交通枢纽进行实测和模拟,探究航站楼交通枢纽风环境现状。应用实地测试的方法对其室内风环... 详细信息

应用绿色节能技术对公共建筑进行改造,降低公共建筑的碳排放并提升其室内风环境水平是目前亟须解决的问题。在冬季,对西安咸阳国际机场T3航站楼交通枢纽进行实测和模拟,探究航站楼交通枢纽风环境现状。应用实地测试的方法对其室内风环境进行了研究。研究结果表明:该航站楼交通枢纽室内温度高于室外温度且变化平稳;室内的相对湿度在90%以上,处于国家标准范围内且变化平稳;门斗能有效改善室内的风环境;室内风速受室外风速影响较大。该研究能够为提高航站楼交通枢纽风环境、降低能耗和碳排放提供实测和模拟数据支撑。

关键词：寒冷地区航站楼交通枢纽室内风环境实地测试风环境模拟

New matrix of MALDI-TOF MS for analysis of small molecules

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Chinese Chemical Letters 2009年第12期20卷 1495-1497页

作者： shu Zhang Yi Chen Jian An liu Shao xiang Xiong Guang Hui Wangx Jun Chen Guo Qiang Yang Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

New matrix, metal-phthalocyanine （MPc）, of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） was used for analysis of small molecules （usually 〈500 Da）. By using MPcs as matrices, small molecular samples were moved to high mass-to-charge region where there was no interference caused by the traditional matrices. The mass of the target analvte was obtained by simple calculation.

关键词： MALDI-TOF MS Small molecules Metal-phthalocyanines New matrix

Computational Assessment of Crown Ether Complexes of Actinyls

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Computational Assessment of Crown Ether Complexes of Actinyl...

中国化学会第八届全国物理无机化学学术会议

作者： shu-xian Hu Jun Li Beijing Computational Science Research Center Department of Chemistry Tsinghua University

To further fundamental understanding of the nature and extent of covalency in actinyl–ligand bonding, and the benefits that this may have for the design of new ligands for nuclear waste separation, there is burgeoning interest in the nature of actinyl complexes with polydentate or multiple-point-donor ligands, such as crown *** are few cases of structurally authenticated molecular actinyl–crown bonds under ambient *** report here the computational characterization of AnO–(15-crown-5) complexes, where An = U, Np, Pu, Am, and Cm, and 15-crown-5 is the cyclic polyether ligand with five ether oxygen *** the gas-phase complex the actinyl group is located inside of the crown ether, tilted slightly out of the plane of the five equatorial oxygen atoms that coordinate the actinide metal *** actinyl–cyclic ether complexes are found to exhibit a conventional conformation, with typical An–Oaxial and An–Oequatorial distances and angles.A striking result is the enhanced stability of the insertion complex for UO versus NpO, PuO, AmO and CmO, which is evaluated in the context of An–O binding strengths(*** covalency), and may have ramifications for the utility of actinyl-crown complexes in separations applications.

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来源： cnki会议评论

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平面小型化双陷波天线设计

电子学报 2016年第10期44卷 2495-2500页

作者：刘阿玄陈蕾钟显江刘淑芳西安电子科技大学天线与微波技术国家重点实验室陕西西安710071

本文设计了一种具有双频陷波特性的小型化平面单极子天线.该天线由开有π型与W型缝隙的辐射贴片和一对L型分支组成.L型分支的作用是能够激励额外谐振,从而增加阻抗带宽,π型和W型缝隙能够实现双陷波特性.该天线可以实现超过130%的带宽（... 详细信息

本文设计了一种具有双频陷波特性的小型化平面单极子天线.该天线由开有π型与W型缝隙的辐射贴片和一对L型分支组成.L型分支的作用是能够激励额外谐振,从而增加阻抗带宽,π型和W型缝隙能够实现双陷波特性.该天线可以实现超过130%的带宽（2.77～13.62 GHz）,最大的特点是具有12×18×1.6 mm3的小型化尺寸.最终的仿真和测试结果显示其在整个超宽带频段内具有良好的陷波特性、增益和全向辐射特性.

关键词：小型化单极子天线双陷波性能超宽带应用

基于OBE理念下的“物理化学实验”教学改革探究

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安徽化工 2024年第1期50卷 190-193页

作者：唐森张鹏陈显玲柳富杰陈燕萌苏龙广西科技师范学院食品与生化工程学院广西来宾546199

“物理化学实验”是食品类专业的一门核心必修课程,具有很强的理论性与实践性。在传统教育模式下,学生无法将理论知识充分运用到实践中,导致教学效果不尽如人意。在工程专业认证的背景下,基于OBE教育理念,在“物理化学实验”教学中融入... 详细信息

“物理化学实验”是食品类专业的一门核心必修课程,具有很强的理论性与实践性。在传统教育模式下,学生无法将理论知识充分运用到实践中,导致教学效果不尽如人意。在工程专业认证的背景下,基于OBE教育理念,在“物理化学实验”教学中融入成果导向教育理论,对于学生未来的发展以及推动工程专业认证具有非常重要的意义。从教学实践出发,以成果导向教育理论为指导,从“物理化学实验”课程教学设计的整理思路入手,全面阐述基于OBE理念的“物理化学实验”课程教学改革的探索,以期达到良好的教学效果,并满足社会对人才的需求。

关键词： OBE 物理化学实验教学改革工程认证

维普期刊数据库博看期刊

Radio frequency interference detection based on the AC-UNet model

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Research in Astronomy and Astrophysics 2021年第5期21卷 168-178页

作者： Rui-Qing Yan Cong Dai Wei liu Ji-Xia Li Si-Ying Chen xian-Chuan Yu Shi-Fan Zuo Xue-Lei Chen College of Information Science and Technology Beijing Normal UniversityBeijing 100875China National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Radio frequency interference(RFI)is a serious issue in radio *** paper proposes a U-Net network model with atrous convolution to detect *** the ability of convolutional neural networks to extract image features of RFI,and learning RFI distribution patterns,the detection model of the RFI is *** use observational data containing real RFIs obtained by the Tianlai telescope to train the model so that the model can detect *** the probability of a data point being RFI pixel by pixel,and set a *** the same time the dropout layer was added to avoid overfitting *** the predicted probability of a data point exceeds the threshold,it is considered that there is RFI,and if the predicted probability of a data point does not exceed the threshold,then it is considered that there is no RFI,so that the part of the image with RFI is *** results show that this approach can achieve satisfactory accuracy in the detection of radio observation images with a small amount of RFI.

关键词： methods:data analysis techniques:image processing methods:observational

Functions of Phytochrome in Rice Growth and Development

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Rice science 2011年第3期18卷 231-237页

作者： GU Jian-wei liu Jing XUE Yan-jiu ZANG Xin XIE xian-zhi Department of Bioengineering Zhengzhou University Zhengzhou 450001 China High-Tech Research Center Shandong Academy of Agricultural Sciences Jinan 250100 China Laboratory of Crop Genetic Improvement and Biotechnology Huanghuaihai Ministry of Agriculture Jinan 250100 China

Phytochrome family mainly senses red and far-red light to regulate a range of developmental processes throughout the life cycle of plants. Rice phytochrome gene family is composed of three members known as PHYA, PHYB and PHYC. It has been elucidated that individual phytochromes display both unique and overlapping roles in rice photomorphogenesis by characterization of all rice phytochrome mutants including single mutants, all combinations of double mutants as well as triple mutants. Based on the published data and authors’ ongoing studies, current knowledge of rice phytochrome functions in regulating seedling de-etiolation, root gravitropic response and elongation, plant architecture, flowering time and fertility is summarized. Additionally, the important issues in the field of rice phytochromes are proposed.

关键词： rice phytochrome gene photomorphogenesis growth and development function