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经验爬虫应用于网络地图服务获取

测绘与空间地理信息 2017年第3期40卷 14-16,21页

作者：钱建国马占武辽宁工程技术大学测绘与地理科学学院辽宁阜新123000

网络地图服务已经渗透到国民经济的方方面面,如何从海量的地图服务中获取需要的数据成为当下研究的热点问题。本文针对目前Web地图服务数据在使用爬虫技术获取中,存在效率和准确性低的问题,提出在经典网络爬虫基础上,增加"经验树"环节,... 详细信息

网络地图服务已经渗透到国民经济的方方面面,如何从海量的地图服务中获取需要的数据成为当下研究的热点问题。本文针对目前Web地图服务数据在使用爬虫技术获取中,存在效率和准确性低的问题,提出在经典网络爬虫基础上,增加"经验树"环节,实现了"经验爬虫"。将改进后的"经验爬虫"与其他3种经典爬虫爬取的结果对比分析,"经验爬虫"爬取的效率和准确性是其他3种经典爬虫均值的2倍以上。

关键词：网络地图服务经验树经验爬虫网络爬虫

A density functional theory study on the interaction between uo_2^(2+) and the carbamoylphosphoramidic acid ligand for uranium extraction from seawater

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Nuclear Science and Techniques 2018年第6期29卷 128-140页

作者： Xiao-Jing Guo Cheng Li Jiang-Tao Hu Hong-Juan ma Hong-Liang Qian Shanghai Institute of Applied Physics Chinese Academy of Sciences School of Engineering China Pharmaceutical University

Phosphorylurea molecules, which contain both phosphoryl and carbonyl groups, are considered efficient extractants for uo_2^(2+). This study aims to explain the complexation of uo_2^(2+)with carbamoylphosphoramidic acid(CPo), a simple model for phosphorylurea, for ligand design for uranium recovery from seawater using density functional theory calculations, natural bond order analysis,and the quantum theory of atoms in molecules. The results showed that, when CPo acts as a monodentate ligand, the affinity of phosphoryl for uo_2^(2+)is stronger than that of carbonyl, and CPo coordinates with uo_2^(2+)through the phosphoryl oxygen atom. When CPo serves as a bidentate ligand, both the phosphoryl and carbonyl oxygen atoms connect to.uo.2^(2+), and the U–o(carbonyl) bond plays a more important role than the U–o(phosphoryl) bond in the interaction between uo_2^(2+)and CPo. This paradox may be caused by the significant charge transfer from the U–o(carbonyl) p bond orbital to the C–N σ antibond orbital of the bidentate CPo. The NH spacer between the phosphoryl and carbonyl groups could ensure the delocalization of the electron system of the molecule. The bidentate binding motif is favored by entropy and opposed by enthalpy, while the monodentate binding motif is favored by enthalpy and opposed by entropy. Ultimately, the bidentate binding motif is more favorable than the monodentate one. As expected, the interaction between uo_2^(2+)and the deprotonated CPo is stronger than that between uo_2^(2+)and the neutral CPo. Comparing the interaction between uo_2^(2+)and CPo with that between uo_2^(2+)and Nphenylcarbamoylphosphoramidic acid(Ph CPo), formed by replacing one hydrogen atom from the terminal nitrogen atom of CPo with a phenyl group, the phenyl substituent at the terminal nitrogen atom of Ph CPo shows a slightly negative effect on the interaction between uo_2^(2+)and Ph CPo.

关键词：相互作用理论学习海水密度抽取 CPo 铀苯基取代

氯化氧铋/多孔钛羟基磷灰石的制备及其对乙醛的催化降解性能

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硅酸盐学报 2018年第5期46卷 715-722页

作者：王俊忠李心昕郭明阳马俊森王延生张广田肖凤娟石家庄铁道大学材料科学与工程学院、河北省交通工程重点实验室石家庄050043 河北省建筑科学研究院石家庄050021

以多孔碳酸钙为模板，采用共沉淀法合成了高比表面积的球形氯化氧铋／多孔钛羟基磷灰石（BioCl／***）复合材料，并对其结构和光吸收性能进行了测定，探讨了BioCl／P-TiHA复合材料在可见光下对乙醛的催化降解性能、降解路径和反应机理... 详细信息

以多孔碳酸钙为模板，采用共沉淀法合成了高比表面积的球形氯化氧铋／多孔钛羟基磷灰石（BioCl／***）复合材料，并对其结构和光吸收性能进行了测定，探讨了BioCl／P-TiHA复合材料在可见光下对乙醛的催化降解性能、降解路径和反应机理。结果表明：合成的BioCl／P-TiHA与目标产物结构一致，当BioCl和TiHA的摩尔比为5：1时，于光照120min条件下，BioCUP-TiHA对乙醛的催化降解效率可达89．6％，降解反应符合一级反应动力学。BioCl/P-TiHA具有较小的禁带宽度和良好的稳定性，可以多次重复循环利用。

关键词：氯化氧铋多孔钛羟基磷灰石乙醛光催化降解

The specific surface area of methane hydrate formed in different conditions and manners

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Science China Chemistry 2009年第3期52卷 381-386页

作者： WANG XiuLin SUN ChangYu CHEN GuangJin YANG LanYing ma QingLan CHEN Jun TANG XuLong LIU Peng State Key Laboratory of Heavy oil Processing China University of PetroleumBeijing 102249China

The specific surface area of methane hydrates, formed both in the presence and absence of sodium dodecyl sulfate (SDS) and processed in different manners (stirring, compacting, holding the hydrates at the fo.mation conditions for different periods of time, cooling the hydrates for different periods of time before depressurizing them), was measured under atmospheric pressure and temperatures below ice point. It was found that the specific surface area of hydrate increased with the decreasing temperature. The methane hydrate in the presence of SDS was shown to be of bigger specific surface areas than pure methane hydrates. The experimental results further demonstrated that the manners of forming and processing hydrates affected the specific surface area of hydrate samples. Stirring or compacting made the hydrate become finer and led to a bigger specific surface area.

关键词： methane hydrate the specific surface area SDS

Synthesis and Structure of a New Dinuclear Uranyl Complex

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Chinese Chemical Letters 2002年第6期13卷 583-586页

作者： Shang Ying LIU Yong Sheng LIU Wen Xing ZHANG Chang Qin ma De Hua JIANG College of Chemistry and Chemical Engineering Shandong UniversityJinan 250100

With a heptadentate compartmental Schiff-base ligand H3L (1, 3-di[o-(salicylimino) ph- enoxyl]-2-propanol), a new binuclear diuranyl complex [(uo2)2L(oH)]?DMF, C38H45N5o13U2, was synthesized and the crystal structure was determined by X-ray diffraction techniques. The coordination geometry are two pentagonal bipyramids. In each pentagon four kinds of U-o (phenoxido, hydroxo, alkoxo and ether oxo) bonds are discussed.

关键词： Dinuclear uranyl complex synthesis structure.

血栓弹力图在儿童过敏性紫癜中的临床应用研究

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国际检验医学杂志 2015年第23期36卷 3395-3397页

作者：郭飞波湖北省天门市第一人民医院检验科湖北天门431700

目的应用血栓弹力图（TEG）分析儿童过敏性紫癜（HSP）的凝血状态。方法选取2013年2~7月于同济医院小儿内科住院治疗的HSP患儿81例,并根据临床表现分为HSP发作组（43例）和HSP缓解组（38例）,另选取41例健康查体儿童为对照组,采用TEG仪... 详细信息

目的应用血栓弹力图（TEG）分析儿童过敏性紫癜（HSP）的凝血状态。方法选取2013年2~7月于同济医院小儿内科住院治疗的HSP患儿81例,并根据临床表现分为HSP发作组（43例）和HSP缓解组（38例）,另选取41例健康查体儿童为对照组,采用TEG仪分别测定凝血反应时间（R）、凝血形成时间（K）、α角、最大振幅（ma）、血凝块溶解百分比（EPL）、30min血凝块幅度减少速率（Ly30）和凝血指数（CI）,并进行比较分析。结果与对照组比较,HSP发作组R值和K值降低,α角、ma值、CI、EPL和Ly30均增加,差异均有统计学意义（P〈0.05）;与HSP发作组比较,HSP缓解组患儿R值和K值增高,α角、ma值、CI、EPL及Ly30均减小,差异均有统计学意义（P〈0.05）。结论 HSP患儿血液凝固性存在异常,并随着病情缓解而改变,TEG对HSP患儿血凝状态的检测具有重要的参考价值。

关键词：过敏性紫癜血栓弹力图凝血状态

Development of a miniaturized 3D organoid culture platform for ultra-high-throughput screening

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Journal of Molecular Cell Biology 2020年第8期12卷 630-643页

作者： Yuhong Du Xingnan Li Qiankun Niu Xiulei Mo Min Qui Tingxuan ma Calvin J.Kuo Haian Fu Department of Pharmacology and Chemical Biology and Emory Chemical Biology Discovery Center Emory University School of MedicineAtlantaGAUSA Department of Medicine Division of HematologyStanford University School of MedicineStanfordCAUSA

The recent advent of robust methods to grow human tissues as 3D organoids allows us to recapitulate the 3D architecture of tumors in an in vitro setting and offers a new orthogonal approach for drug ***,organoid culturing with extracellular matrix to support 3D architecture has been challenging for high-throughput screening(HTS)-based drug discovery due to technical *** genetically engineered human colon organoids as a model system,here we report our effort to miniaturize such 3D organoid culture with extracellular matrix support in high-density plates to enable *** first established organoid culturing in a 384-well plate fo.mat and validated its application in a cell viability HTS assay by screening a 2036-compound *** further miniaturized the 3D organoid culturing in a 1536-well ultra-HTS fo.mat and demonstrated its robust perfo.mance for large-scale primary compound *** miniaturized organoid culturing method may be adapted to other types of *** leveraging the power of 3D organoid culture in a high-density plate fo.mat,we provide a physiologically relevant screening platform to model tumors to accelerate organoid-based research and drug discovery.

关键词： human colon organoids KRAS^G12D 3D culture 384-well plate high-throughput screening(HTS) 1536-well plate ultra-HTS(uHTS)

高温联合PM_(2.5)暴露致CoPD大鼠肺损伤的机制研究

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环境与职业医学 2018年第10期35卷 898-904页

作者：郭蕾张凯刘江涛马月玲张莉牛静萍罗斌兰州大学公共卫生学院甘肃兰州730000

[目的]研究高温及大气PM_(2.5)暴露致慢性阻塞性肺疾病(chronic obstructive pulmonary disease,CoPD)大鼠肺组织损伤的作用机制。[方法] 84只7周龄健康SPF级雄性Wistar大鼠随机分成对照组和CoPD模型组,利用卷烟烟雾和气管内滴注脂多糖... 详细信息

[目的]研究高温及大气PM_(2.5)暴露致慢性阻塞性肺疾病(chronic obstructive pulmonary disease,CoPD)大鼠肺组织损伤的作用机制。[方法] 84只7周龄健康SPF级雄性Wistar大鼠随机分成对照组和CoPD模型组,利用卷烟烟雾和气管内滴注脂多糖的方法建立CoPD大鼠模型。对照组和CoPD模型组行PM_(2.5)气管滴注(0、3.2、12.8 mg/mL),然后暴露于高温(40℃)8 h,每天1次,持续3 d,同时选择20℃作为常温对照温度。末次染毒24 h后,检测两组大鼠的最大吸气流量(peak inspiratory flow,PIF)和最大呼气流量(peak expiratory flow,PEF)等肺功能指标;HE染色制作肺组织病理切片;利用试剂盒测定CoPD大鼠肺组织超氧化物歧化酶(superoxide dismutase,SoD)、诱导性一氧化氮合酶(inducible nitric oxide synthase,iNoS)、丙二醛(malonyldialdehyde,MDA)的含量;采用链霉素抗生物素蛋白-过氧化物酶连接法测定8-羟基脱氧鸟苷(8-hydroxydeoxyguanosine,8-oHdG)表达水平;采用蛋白质免疫印迹法分析血红素氧合酶(heme oxygenase,Ho-1)的表达水平。采用析因分析法分析温度、PM_(2.5)和CoPD模型对肺功能的影响,以及温度、PM_(2.5)对氧化应激指标的影响。[结果]高温状态下,对照组和CoPD组大鼠经不同剂量PM_(2.5)染毒,PIF和PEF均低于常温状态相应染毒剂量组(均P oPD三者存在交互作用(F=7.585,P oPD组大鼠肺损伤明显,尤其在高温和PM_(2.5)暴露下变化较对照组更为明显。高温状态CoPD组大鼠肺组织中iNoS含量在各PM_(2.5)染毒剂量下均高于相应的常温状态CoPD组(均P oS(F=0.128,P=0.880)及SoD(F=1.792,P=0.175)的影响不存在交互作用。此外,高温状态CoPD组大鼠肺组织8-oHd G蛋白表达在0 mg/mL和3.2 mg/mL PM_(2.5)染毒剂量组时高于相应剂量下的常温状态组(P oPD组大鼠Ho-1蛋白表达在0、12.8 mg/mL PM_(2.5)染毒剂量下低于常温状态组(P oPD大鼠肺功能更易受PM_(2.5)的影响,氧化/抗氧化系统失衡可能是高温和PM_(2.5)联合暴露致CoPD大鼠肺组织损伤的主要机制。

关键词：高温 PM2.5 慢性阻塞性肺疾病氧化应激

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接触角测量中型煤与原煤的适用性研究

中国安全生产科学技术 2018年第8期14卷 129-133页

作者：郑梦浩王兆丰岳基伟马树俊霍肖肖河南理工大学安全科学与工程学院河南焦作454000 煤矿灾害预防与抢险救灾教育部工程研究中心河南焦作454000

为了分析成型煤粉法与原煤研磨法对煤样接触角测量结果的影响,按照成型煤粉法与原煤研磨法制备试验所用煤样试片,并采用蒸馏水及不同种类、不同浓度的表面活性剂对2种试样的接触角进行测量。研究结果表明:在本试验所用的任意一种溶液下... 详细信息

为了分析成型煤粉法与原煤研磨法对煤样接触角测量结果的影响,按照成型煤粉法与原煤研磨法制备试验所用煤样试片,并采用蒸馏水及不同种类、不同浓度的表面活性剂对2种试样的接触角进行测量。研究结果表明:在本试验所用的任意一种溶液下,采用成型煤粉法所测得的表面接触角比采用原煤研磨法所测得的表面接触角小;通过对比型煤与原煤的吸水率,发现原煤的吸水率远小于型煤的吸水率;采用原煤研磨法所测得的接触角较为准确;成型煤粉法较适用于无法制得原煤煤样试片的接触角测量。

关键词：成型煤粉法原煤研磨法接触角适用性