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Journal of University of Science and Technology Beijing 2008年第5期15卷 605-610页

作者： Lili Cui Huili Fan junping xiao xiaowei Xu Dong Su Applied Science School University of Science and Technology Beijing Beijing 100083 China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Civil ＆ Environment Engineering School University of Science and Technology Beijing Beijing 100083 China

A new method was reported for surface modification of an up-conversion luminescence material with hydrosulfide group. The factors that may influence the surface modification,such as reaction time,amount of catalyzer and modifier,and reaction solvent,were investigated. The optimal conditions were that the reaction time,the quantity of the basic catalyzer,the quantity of modifier and the volume of reaction solvent were 40 min,1.0,1.0,and 40 mL,respectively. The results indicated that hydrosulfide group content modified on the surface of up-conversion luminescence material reached to 0.1430 mmol/g,and this modified up-conversion luminescence material could be widely used in the study of structure of protein and the property of microenvironment.

关键词： upconversation surface modification luminescence material hydrosulfide react condition

Tectonic thermal history and its significance on the formation of oil and gas accumulation and mineral deposit in Ordos Basin

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Science China Earth Sciences 2007年第Z2期50卷 27-38页

作者： REN ZhanLi ZHANG Sheng GAO ShengLi CUI junping xiao YuanYuan xiao Hui State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China Department of Geology Northwest University Xi'an 710069 China

The analyzing data on stratigraphic temperature measurement , thermal conductivity of the strata and radioactive heat production rate show that the present average geothermal gradient in the Ordos Basin is 2.93℃/100 m, and the average heat flow value is 61.78 mW/m2, which belongs to the mesothermal basin, and the value of the present geothermal gradient and heat flow in the east is higher than that in the west. The sandstone radioactive heat production rate of Zhiluo Group in Dongsheng Uranium deposits of Yimeng uplift is obviously higher in the mudstone, indicating that there exists a uranium anomaly. Based on studies of the present thermal field of the basin, the late-Mesozoic paleotemperature and paleogeothermal gradient are determined by using different kinds of paleotemperature methods. According to the anomaly of the late-Mesozoic paleotemperature gradient and magmatic event age, there was a tectonic thermal event in the early Cretaceous epoch of late-Mesozoic. This article rebuilds tectonic thermal history of different tectonic units by thermal history simulation using basin simulating software. The evolution of oil-gas and coal, and accumulation (mineralization) of mineral uranium are all controlled by the tectonic thermal history in the Ordos basin, especially by the tectonic thermal event that happened in the late Mesozoic. For both the gas source rocks of upper Paleozoic group and lower paleozoic group, the gas was largely generated in the early Cretaceous epoch of the late Mesozoic. The main petroleum generation period for Yanchang Group in Triassic system is the early Cretaceous epoch too, and the highest thermal maturity of the coal of Permo-Carboniferous, Triassic, and Jurassic reaches is the early Cretaceous epoch also. Early Cretaceous epoch is still one of the most important mineralizing periods of uranium.

关键词： Ordos Basin, heat flow, geothermal gradient, paleotemperature, tectonic thermal event, thermal history, accumulation period

Surface modification of an up-conversion luminescence material by overcoating with SiO_2 and its characterization

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Rare Metals 2007年第3期26卷 276-279页

作者： CUI Lili LIU Jiemin FAN Huili XU xiaowei YANG Min xiao junping Department of Chemistry University of Science and Technology Beijing Beijing 100083 China Department of Inorganic Nonmetallic Materials University of Science and Technology Beijing Beijing 100083 China

The surface of an up-conversion luminescence material was modified by overcoating with SiOa, which was synthesized from a hydrolysis progress of telraethoxysilane （TEOS） in alkalescent condition. By analyzing the hydrolyzed mechanism of TEOS, it was found that there was not only physical adsorption but also chemical bonding between the up-conversion material and SiO2. At the same time, some adsorption bands at 1100, 475, 950, and 3500 cm^-1 were found by FI-IR, which were the characteristic bands of Si-OH and Si-O-Si. By analyzing the surface elements of the coated material by XPS, it was found that its surface only included Si, O, and C elements, and not F and Y. In the picture of XRD, there was no additional peak after surface modification, suggesting that the silica shell was amorphous. The small peak at 20 = 23° in the X-ray diffraction pattern of the coated material was caused by the amorphous SiO2 shell, and the TEM image also proved that the surface of the material was successfully modified by overcoating with SiO2. The amount of hydroxyls was then increased on the surface of the material, which made it easy to connect with other active groups.

关键词： surface modification SiO2 sol-gel up-conversation luminescence

Comparison study of two aldehyde group finishing agents in surface modification of up-conversion luminescence materials

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Rare Metals 2008年第2期27卷 127-130页

作者： CUI Lili FAN Huili xiao junping XU xiaowei Department of Chemistry University of Science and Technology Beijing Beijing 100083 China Department of Inorganic Nonmetallic Materials University of Science and Technology Beijing Beijing 100083 China

Surface modification of up-conversion luminescence materials （Na[Y0.57Yb0.39Er0.04]F4 modified by amino groups） by grafting and modifying with aldehyde groups was studied by means of Fourier transform infrared spectroscopy （FTIR）, scanning electron microscopy （SEM）, thermogravimetric analysis （TGA）, and emission spectrum （EM）. The surface modification effect was compared using two different finishhag agents, p-phthalaldehyde and glutaraldehyde. It was found that the surface of up-conversion luminescence materials could be modified by aldehyde groups of the two finishing agents, the systematic dispersibility and the thermostability of the up-conversion luminescence material modified by p-phthalaldehyde were better than those of the material modified by glutaraldehyde, and the luminous intensity of the material modified by p-phthalaldehyde was increased. The AI （the ratio of the suspended segmental quality in the specimen to the total mass of the specimen） of the material modified by p-phthalaldehyde was higher than that of the material modified by glutaraldehyde. It is obviously seen that the embellishment effect of p-phthalaldehyde as a finishing agent was better than that of glutaraldehyde. In addition, the reasons why p-phthalaldehyde is a good finishing agent are also explained.

关键词： luminescence materials up-conversion surface modification luminescence aldehyde groups

First-principles calculations of structural transition and elastic properties of Si4Ge4 alloy under high pressure

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First-principles calculations of structural transition and e...

第十八届中国高压科学学术会议

作者： xiaocui Yang Hongyuan Ma junping xiao Zhuo Yu Department of Physics Baicheng Normal University

An investigation on the structure stability and elastic properties of Si4Ge4under high pressure was conducted using first-principles *** calculations were performed using the plane-wave pseudopotential DFT method as implemented in the CASTEP 7.0 simulation package,using norm-conserving pseudopotentials within the local density approximation(LDA)as parameterized by Perdew and *** convergence criteria for structure optimization and energy calculation were set to ultrafine quality with a kinetic energy cutoff of 390 e V and Monkhorst k-point meshes of 4×4×*** self-consistent convergence accuracy was set to be5.0×10-6 e V/*** convergence criterion for the maximal force between atoms was 0.01 e V/?.The maximum displacement was 5.0×10-4?,and the stress was set to be 0.02 GPa.

关键词： first-principles calculations structural transition elastic property high pressure

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新型功能性倍半硅氧烷的合成与表征

化工新型材料 2012年第1期40卷 137-140页

作者：肖俊平王欣湖北新蓝天新材料股份有限公司仙桃433003

以三氯丙基三甲氧基硅烷、苯基三甲氧基硅烷为原料,在一定条件下合成了笼形八聚(三氯丙基)倍半硅氧烷和双层倍半硅氧烷。进一步与叠氮钠、冠醚等通过取代反应、点击反应等方法来合成多种功能性的倍半硅氧烷,它们在复合材料等领域将有很... 详细信息

以三氯丙基三甲氧基硅烷、苯基三甲氧基硅烷为原料,在一定条件下合成了笼形八聚(三氯丙基)倍半硅氧烷和双层倍半硅氧烷。进一步与叠氮钠、冠醚等通过取代反应、点击反应等方法来合成多种功能性的倍半硅氧烷,它们在复合材料等领域将有很好的应用前景。利用1-核磁共振光谱、13-核磁共振光谱、29-Si核磁共振光谱、基质辅助激光解吸电离飞行时间质谱等手段,对它们的结构分别进行了表征。

关键词：倍半硅氧烷冠醚叠氮化点击反应表征

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高色纯度荧光碳点的制备和应用研究进展

材料工程 2023年第11期51卷 14-22页

作者：李亚楠刘云刘春艳肖军平北京科技大学化学与生物工程学院北京100083 中国科学院理化技术研究所北京100190

窄带宽的高色纯度发光材料在超高清显示和照明、超分辨成像和传感、生物成像以及防伪等领域具有广泛用途。目前研究和发展的高色纯度荧光材料主要是Ⅱ-Ⅵ族半导体量子点、卤化物钙钛矿纳米晶等。这些材料普遍含有剧毒的过渡金属离子镉... 详细信息

窄带宽的高色纯度发光材料在超高清显示和照明、超分辨成像和传感、生物成像以及防伪等领域具有广泛用途。目前研究和发展的高色纯度荧光材料主要是Ⅱ-Ⅵ族半导体量子点、卤化物钙钛矿纳米晶等。这些材料普遍含有剧毒的过渡金属离子镉和铅等,且环境稳定性较低。与之相比,碳点具有不含重金属离子、光/化学稳定性高、毒性低和原料来源广泛的优点。因此,发展碳点基高色纯度发光材料具有重要的理论和现实意义。基于此,本文系统总结高色纯度碳点在合成与应用方面的国内外研究进展,重点讨论前驱体种类、合成方法等对碳点发光位置和发光峰色纯度的影响,以及在LED、传感和成像等领域的研究进展。展望高色纯度碳点在规模合成、光谱特性如发光位置调制、色纯度和发光效率提升、发光机理研究以及新应用领域拓展方面所面临的机遇和挑战。

关键词：高色纯度碳点合成应用

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再辩“四端七情”理气论

东疆学刊 2005年第4期22卷 66-70页

作者：肖君平延边大学人文社会科学学院吉林延吉133002

李退溪在总体上继承朱子理论的同时,以“理气”论“四端七情”,提出了“四端七情理气互发说”,把“四端七情”问题提升到本体论的高度,在终极意义上着重论证了四端与七情的差异,其思想本旨在于对“理”的透彻理解和充分的实践。退溪对... 详细信息

李退溪在总体上继承朱子理论的同时,以“理气”论“四端七情”,提出了“四端七情理气互发说”,把“四端七情”问题提升到本体论的高度,在终极意义上着重论证了四端与七情的差异,其思想本旨在于对“理”的透彻理解和充分的实践。退溪对“理”的穷究,是为了要凸显人道德的主体性,希望通过道德主体的自觉操持,实现万物存有的价值和人生的意义。

关键词：四端七情理气论理气互发四端道德主体李退溪 “理” 本体论朱子实践

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纳米材料表面修饰的研究进展

材料导报 2006年第F5期20卷 5-7页

作者：崔黎黎范慧俐肖军平杨敏北京科技大学应用科学学院化学系北京100083

通过材料的表面修饰与包覆以改善材料的表面性质乃至改变材料的相结构和性质,已经成为纳米材料制备和应用的关键技术。综述了近年来纳米微粒表面修饰的研究进展,并对纳米微粒表面改性的各种方法原理及其特点进行了归纳和分析。

关键词：纳米材料表面修饰进展

固体碱催化环己酮和碳酸二甲酯合成庚二酸二甲酯

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石油化工 2007年第8期36卷 812-815页

作者：吴都督赵宁李军平肖福魁魏伟孙予罕中国科学院山西煤炭化学研究所煤转化国家重点室验室山西太原030001

以固体碱为催化剂,研究了环己酮与碳酸二甲酯(DMC)合成庚二酸二甲酯的反应性能,考察了反应温度、反应时间、催化剂用量和原料配比对合成反应的影响。实验结果表明,偏酸性的固体碱催化剂不利于庚二酸二甲酯的生成,而具有中强碱位的MgO对... 详细信息

以固体碱为催化剂,研究了环己酮与碳酸二甲酯(DMC)合成庚二酸二甲酯的反应性能,考察了反应温度、反应时间、催化剂用量和原料配比对合成反应的影响。实验结果表明,偏酸性的固体碱催化剂不利于庚二酸二甲酯的生成,而具有中强碱位的MgO对该合成反应具有较好的催化性能;得到了较适宜的工艺条件:MgO为催化剂,反应温度260℃,反应时间5h,催化剂用量为反应物质量的1.5%,n(环己酮)∶n(DMC)=1∶4,在此条件下,环己酮的转化率为83.6%,庚二酸二甲酯的选择性为51.8%;该反应的主要副产物为环己酮自身缩合产物(2-环己烯基环己酮)和环己酮甲基化产物(2-甲基环己酮和2,6-二甲基环己酮)等。

关键词：固体碱催化剂碳酸二甲酯环己酮庚二酸二甲酯