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超致密矮星系的潮汐剥离演化序列

科学通报 2024年第4期69卷 473-475页

作者：王凯翔刘成则北京大学物理学院天文学系北京100871 北京大学科维理天文与天体物理研究所北京100871 上海交通大学物理与天文学院天文学系上海200240 上海交通大学李政道研究所上海200240

长期以来,星系(galaxy)和星团(star cluster)被认为是截然不同的两类天体.星系在暗物质晕中诞生成长,有较为复杂的恒星形成历史,是由大量恒星、气体、尘埃和暗物质等物质组成的天体系统,往往有着庞大的结构.星系的形态也多种多样,包括... 详细信息

长期以来,星系(galaxy)和星团(star cluster)被认为是截然不同的两类天体.星系在暗物质晕中诞生成长,有较为复杂的恒星形成历史,是由大量恒星、气体、尘埃和暗物质等物质组成的天体系统,往往有着庞大的结构.星系的形态也多种多样,包括椭圆星系、旋涡星系、不规则星系等.多个星系通常以星系群和星系团的形式存在,形成宇宙中大尺度结构的同时,也互相影响着各自的演化轨迹.

关键词：大尺度结构旋涡星系不规则星系椭圆星系恒星形成星系群星系团暗物质

Degradation of Phenol by Hydroxyl Radicals on Different Coating Lead Dioxide Electrodes

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Chemical Research in Chinese Universities 2008年第3期24卷 285-290页

作者： LIU Miao TANG Yi-nan wang Li HU Yan-dong jiao Xin-qian HUANG Wen-peng College of Environment and Resources Jilin University Changchun 130012 P R. China School of Environment and Nature Resources Renmin University of China Beijing 100872 P R. China Daqing Vocational College Daqing 163255 P R. China Jilin Province Environmental Monitoring Institution Changchun 130021 P R. China

Lead dioxide electrodes on Ti substrates were prepared by thermal-deposition or electro-deposition. The amount of hydroxyl radicals generated at the electrodes prepared by the above-mentioned two methods was compared with that at the electrodes mingled with Bi or La prepared by electro-deposition. The experimental results indicate that the highest concentration of hydroxyl radicals generated by thermal-deposition, electro-deposition mingled with nothing, electro-deposition mingled with Bi or La was 0.781, 1.048, 1.838 or 2.044 μmol/L, respectively. When phenol was electrolyzed on the four electrodes at a current density of 30 mA/cm2, the removal efficiency of phenol after electrolysis for 1.5 h was 87.30%, 93.55%, 97.95% or 98.70%, TOC removal efficiency after electrolysis for 5 h was 86.76%, 94.26%, 98.53% or 99.60%, respectively. Through the degradation experiments of phenol, the amount of hydroxyl radicals was responsible for the removal efficiency of phenol. The electro-catalytic characteristics were investigated by SEM, the generation amount of hydroxyl radicals, the degradation degree of phenol and the stability and conductivity of the electrodes were also investigated. The experimental results indicate that the four electrodes all show good electro-catalytic characteristics; the electro-catalytic characteristics of the electrode mingled with La were superior to those of the other three ones, and the electrochemical degradation of phenol followed one-step reaction dynamics.

关键词： High-performance liquid chromatography Hydroxyl radicals Lead dioxide electrode Thermal-deposition Electro-deposition

Highly Efficient Organic Ultraviolet Photodetectors Based on Re(I) Complexes

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Chemical Research in Chinese Universities 2012年第3期28卷 503-506页

作者： LIU chun-bo wang Long LIU Min LI Chuan-bi LI chun-mei CHE Guang-bo SU Bin College of Chemistry Jilin Normal UniversitySiping 136000P.R.China College of Environmental Engineering Jilin Normal UniversitySiping 136000P.R.China

High response organic ultraviolet photodetectors（UV-PDs） were demonstrated with 4,4＇,4”- tris[3-methyl-pheny（phenyl）amino]triphenylamine（m-MTDATA） and two Re（Ⅰ） complexes, （bathocuproine）- Re（CO）3CI（Re-BCP） and （bathophenanthroline）Re（CO）3Cl（Re-Bphen） to act as the electron donor and acceptor, re- spectively. UV-PDs have the configuration of indium tin oxide（ITO）/m-MTDATA（25 nm）/m-MTDATA：Re-complex （25-35 nm）/Re-complex（20 nm）/LiF（l nm）/Al（200 nm） with different blend layer thicknesses of 25, 30 and 35 nm. The optimized PD based on Re-Bphen offers a corrected-dark photocurrent up to 760μA/cm^2 at -10 V, corresponding to a response of 310 mA/W which is among the best values reported for organic UV-PDs. Excellent electron transport ability makes for such high photo-to-electron conversion.

关键词： Organic ultraviolet photodetector Re(Ⅰ) complex High electron transport ability

Friction compensation design based on state observer and adaptive law for high-accuracy positioning system

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Progress in Natural Science:Materials International 2006年第2期16卷 147-152页

作者： wang Ying, XIONG Zhenhua and DING Han (School of Mechanical Engineering, Shanghai jiao Tong University, Shanghai 200030, China) [a]School of Mechanical Engineering Shanghai Jiao Tong University Shangai China

Friction is one of the main factors that affect the positioning accuracy of motion system. Friction compensation based on friction model is usually adopted to eliminate the nonlinear effect of friction. This paper presents a proportional-plus-derivative (PD) feedback controller with a friction compensator based on LuGre friction model. We also design a state observer to observe the unknown state of LuGre friction model, and adopt a parameter adaptive law and off-line approximation to estimate the parameters of LuGre friction model. Comparative experiments are carried out among our proposed controller, PD controller with friction compensation based on classical friction model, and PD controller without friction compensation. Experimental results demonstrate that our proposed controller can achieve better performance, especially higher positioning accuracy.

关键词： friction compensation state observer adaptive law linear motor motion control.

白蛋白-胆红素评分对急性失代偿心力衰竭患者短期死亡风险的预测价值

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中国心血管病研究 2024年第4期22卷 295-302页

作者：李冠男黄蓉王紫艳马春梅王涟南京大学医学院附属鼓楼医院心内科江苏省南京市210008 江苏大学鼓楼临床医学院心内科

目的探讨白蛋白-胆红素(albumin-bilirubin,ALBI)评分对急性失代偿性心力衰竭(ADHF)患者短期全因死亡的预测价值,联合急性失代偿性心力衰竭国家注册研究(ADHERE)模型能否提高其预测能力。方法连续入选2018年1月至2021年3月在南京鼓楼医... 详细信息

目的探讨白蛋白-胆红素(albumin-bilirubin,ALBI)评分对急性失代偿性心力衰竭(ADHF)患者短期全因死亡的预测价值,联合急性失代偿性心力衰竭国家注册研究(ADHERE)模型能否提高其预测能力。方法连续入选2018年1月至2021年3月在南京鼓楼医院心内科住院的ADHF患者共821例。根据入院ALBI评分,采用三分位法进行分组:低ALBI组(<-2.41,n=273),中ALBI组(-2.41~-2.10,n=274),高ALBI组(≥-2.10,n=274)。比较各组基线临床特征及实验室检查,主要终点为短期(院内或出院后30天内)全因死亡。采用logistics回归分析短期全因死亡的独立危险因素,绘制受试者工作特征(ROC)曲线,计算各模型ROC曲线下面积(AUC),根据约登指数确定最佳临界值,并计算不同模型间净重新分类指数(NRI),采用Z检验比较模型间AUC及NRI的差异。结果共有45例(5.48%)患者在院内及出院后30天内死亡。高ALBI组患者全因死亡率显著高于其他两组(P<0.001)。多因素logistics回归分析显示,ALBI评分(OR=4.012,95%CI 1.598~10.073,P=0.003)、ADHERE模型(OR=2.471,95%CI 1.317~4.434,P=0.004)、B型利钠肽水平(OR=1.000,95%CI 1.000~1.001,P=0.002)是ADHF患者短期全因死亡的独立危险因素。ALBI评分预测短期死亡的最佳临界值为-2.024。ALBI联合ADHERE评分对ADHF患者短期全因死亡的预测能力优于单独评分(ALBI+ADHERE比ADHERE:AUC P=0.008;NRI=0.37,95%CI 0.14~0.56,P<0.001;ALBI+ADHERE比ALBI:NRI=0.37,95%CI 0.14~0.56,P<0.001)。结论ALBI评分与ADHF患者短期全因死亡风险独立相关,且ALBI联合ADHERE模型的预测价值更高。

关键词：白蛋白-胆红素评分 ADHERE模型急性失代偿性心力衰竭死亡

Metallic and ferromagnetic MoS2 nanobelts with vertically aligned edges

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Nano Research 2015年第9期8卷 2946-2953页

作者： Guanchen Xu Xinsheng wang Yupeng Sun Xiao Chen Jingying Zheng Lifei Sun Liying jiao Jinghong Li Department of Chemistry Tsinghua University Beijing 100084 China Key Laboratory of Colloid and Interface Chemistry Shandong University Jinan 250100 China

Edge effects are predicted to significantly impact the properties of low dimensional materials with layered structures. The synthesis of low dimensional materials with copious edges is desired for exploring the effects of edges on the band structure and properties of these materials. Here we developed an approach for synthesizing MoS2 nanobelts terminated with vertically aligned edges by sulfurizing hydrothermally synthesized MoO3 nanobelts in the gas phase through a kinetically driven process; we then investigated the electrical and magnetic properties of these metastable materials. These edge-terminated MoS2 nanobelts were found to be metallic and ferromagnetic, and thus dramatically different from the semiconducting and nonmagnetic two-dimensional （2D） and three-dimensional （3D） 2H-MoS2 materials. The transitions in electrical and magnetic properties elucidate the fact that edges can tune the properties of low dimensional materials. The unique structure and properties of this one-dimensional （1D） MoS2 material will enable its applications in electronics, spintronics, and catalysis.

关键词： MoS2 two-dimensional (2D)atomic crystal,nanobelt,edge effect,metallic,ferromagnetic

Acylation of Quercetin with a Novel Thermophilic Esterase as Biocatalyst

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Chemical Research in Chinese Universities 2012年第2期28卷 225-229页

作者： XIE Xiao-na ZHANG chun-li XUN Er-na wang Jia-xin ZHANG Hong wang Lei wang Zhi The First Hospital of Jilin University Changchun 130021P.R.China Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Physical Education Jilin UniversityChangehun 130012P.R.China

The regioselective acylation of quercetin catalyzed by a novel thermophilic esterase（APE1547） from the archaeon Aeropyrum pernix K1 was successfully conducted in organic *** effects of acyl donor,substrate ratio,organic solvent,temperature,and water activity were *** the optimum conditions,a yield of 74% for its mono ester could be achieved in the reaction for about 6 *** the reaction time extending to about 30 h,the final conversion of quercetin was about 100% and three products were synthesized.

关键词： Quercetin Vinyl acetate APE1547 Acylation

雷火灸辅助治疗对脾胃虚寒型慢性胃炎临床症状的改善效果

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医学信息 2024年第18期37卷 147-150页

作者：陈庆斌钟祥荣王春辉兴国县中医院内一科

目的观察雷火灸辅助治疗对脾胃虚寒型慢性胃炎患者临床症状的改善效果。方法选取2022年4月-2023年4月在我院诊治的66例脾胃虚寒型慢性胃炎患者为研究对象，采用随机数字表法分为对照组和观察组，各组33例。对照组采用常规西医治疗，... 详细信息

目的观察雷火灸辅助治疗对脾胃虚寒型慢性胃炎患者临床症状的改善效果。方法选取2022年4月-2023年4月在我院诊治的66例脾胃虚寒型慢性胃炎患者为研究对象，采用随机数字表法分为对照组和观察组，各组33例。对照组采用常规西医治疗，观察组在对照组基础上采用雷火灸辅助治疗。比较两组临床疗效、临床症状积分（胃脘痛、腹胀、嗳气、反酸）、生活质量评分、不良反应发生率以及治疗满意度。结果观察组治疗总有效率（93.94%）高于对照组（81.82%）(P0.05）；观察组治疗满意度为96.97%，高于对照组的84.85%(P<0.05)。结论雷火灸辅助治疗脾胃虚寒型慢性胃炎可提高治疗效果，减轻临床症状，改善患者生活质量，提高其满意度，且不增加不良反应，具有较理想的辅助效果。

关键词：雷火灸脾胃虚寒型慢性胃炎胃脘痛

苯系物与噪声联合暴露对男工职业性噪声性听力损失的影响

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现代预防医学 2024年第2期51卷 233-237页

作者：樊惠玲焦洁张磊李雨铮姚玲莉王冰郝长付姚武郑州大学公共卫生学院劳动卫生与环境卫生学系河南省第三人民医院(河南省职业病医院) 劳动卫生科

目的探讨苯系物和噪声联合暴露对工人职业性噪声性听力损失(noise-induced hearing loss, NIHL)的影响。方法选择某客车制造企业1 283名男工为研究对象，根据工作场所噪声与苯系物暴露情况将工人分为两组，噪声暴露组889人，苯系物与... 详细信息

目的探讨苯系物和噪声联合暴露对工人职业性噪声性听力损失(noise-induced hearing loss, NIHL)的影响。方法选择某客车制造企业1 283名男工为研究对象，根据工作场所噪声与苯系物暴露情况将工人分为两组，噪声暴露组889人，苯系物与噪声联合暴露组394人。对工人分别进行左、右耳500 Hz、1 000 Hz、2 000 Hz、3 000 Hz、4 000 Hz、6 000 Hz 6个频率的纯音气导听阈测试，比较两组的高频及语频听力损失差异，并分析年龄、工龄、体重指数、吸烟、饮酒、高血压、暴露因素对听力损失的影响。结果苯系物与噪声联合暴露组工人高频听力损失和语频听力损失检出率均高于噪声暴露组(P<0.01);随年龄增加，工人听力损失检出率升高(P<0.01);苯系物与噪声联合暴露、年龄≥40岁、工龄≥20年及饮酒是工人高频听力损失的危险因素(P<0.01);苯系物与噪声联合暴露、年龄≥40岁、工龄10～20年是研究对象语频听力损失的危险因素(P<0.01)。苯系物与噪声联合暴露增加了工人NIHL的风险(OR高频=1.974,OR语频=13.086)。结论苯系物与噪声联合暴露可能对NIHL具有协同作用。

关键词：苯系物噪声联合暴露职业性听力损失