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Synthesis and Luminescence Properties of Tb^3＋-Activated Silicate Oxyapatite Phosphor

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Journal of Chemistry and Chemical Engineering 2011年第9期5卷 841-846页

作者： Yi-Chen Chiu Wei-Ren Liu Yao-Tsung Yeh shyue-ming jang Teng-ming Chen Material and Chemical Research Laboratories Industrial Technology Research Institute Hsinchu 30011 Taiwan Department of Applied Chemistry National Chiao Tung University Hsinchu 30010 Taiwan

A green-emitting phosphor Ca（Tb1-xLax）4（SiO4）3O （CTLS） was synthesized by a solid state reaction. X-ray diffraction, photoluminescence （PL） spectroscopy, reflectance spectra and chromaticity coordinates were carried out in this study. The CaTb4（SiO4）3O host has been known to crystallize in a hexagonal structure with disordering found in the Ca2＋ and Tb3＋ cation sites. The phosphors exhibited highly green-emitting band centered at 541 nm under ultraviolet excitation, which corresponds to the 5D4→7F5 transition. The optimal doping concentration of Tb3＋ was observed to be at 20 mol%, and the PL intensity was found to decline dramatically when the content of Tb3＋ exceeds 20m01% due to concentration quenching. Based on the results, we are currently evaluating the potential application of Ca（Tb,La）4（SiO4）30 as a new green-emitting near-UV LED convertible phosphor.

关键词： Phosphor CaTb4(SiO4)3O silicate apatite.

Luminescence Properties of Green-emitting Phosphors-Sr4Al14O25：Eu2＋ for LED Applications

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Journal of Chemistry and Chemical Engineering 2011年第7期5卷 638-643页

作者： Wei-Ren Liu Chun Che Lin Yi-Chen Chiu Yao-Tsung Yeh shyue-ming jang Ru-Shi Liu Material and Chemical Research Laboratories Industrial Technology Research Institute Hsinchu 30011 Taiwan Department of Chemistry National Taiwan University Taipei 10617 Taiwan

A highly intense green-emitting phosphor of Eu2＋-doped Sr4Al14O25 （SAE：Eu2＋） was synthesized by a solid state reaction. In this study, XRD, PL/PLE, QE, thermal stability and LED package tests are systematically carried out and investigated. The optimized-composition of （Sro 92Eu0.08）4Al14025 exhibited a green emission peak at 497 nm under excitation wavelength of 400 nm, giving the chromaticity coordinates of （0.14, 0.35） with excellent quantum efficiency （98%） compared to those of other green-commodities, such as Ba2SiO4：Eu2＋（90%） and BaMgAl10O17：EU2＋, Mn2＋（92%）. The results demonstrated that SAE：Eu2＋ could be a potential candidate as the NUV-pumping phosphor for applications in light-emitting diodes （LEDs）.

关键词： LEDs phosphors Sr4Al14025 Luminescence EU2+.

Gas Kinetic Scheme for Anisotropic Savage-Hutter Model

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Communications in Computational Physics 2013年第5期13卷 1432-1454页

作者： Wen-Chi Chen Chih-Yu Kuo Keh-ming shyue Yih-Chin Tai Division of Mechanics Research Center for Applied SciencesAcademia SinicaTaipei 115Taiwan Department of Mathematics National Taiwan UniversityTaipei 106Taiwan Department of Hydraulic and Ocean Engineering National Cheng Kung UniversityTainan 701Taiwan

The gas-kinetic scheme is applied to a depth-integrated continuum model for avalanche flows,namely the Savage-Hutter *** this method,the continuum fluxes are calculated based on the pseudo particle motions which are relaxed from nonequilibrium to equilibrium *** processes are described by the Bhatnagar-GrossKrook(BGK)*** benefit of this scheme is its capability to resolve shock discontinuities sharply and to handle the vacuum state without special *** the Savage-Hutter equation bears an anisotropic stress on the tangential space of the topography,the equilibrium distribution function of the microscopic particles are shown to be *** anisotropic stresses are the key to preserve the coordinate objectivity in the Savage-Hutter *** effect of the anisotropic stress is illustrated by two examples:an axisymmetric dam break and a finite mass sliding on an inclined plane *** is found that the propagation of the flow fronts significantly depends on the orientation of the principal axes of the tangential stresses.

关键词： Gas-kinetic scheme BGK equation extended Savage-Hutter equation

装药结构对硬质岩隧洞轮廓成型效果的影响研究

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爆破 2024年第2期41卷 15-22,169页

作者：张光辉张家托王洋程远龙蒋宏杰陈明湖北能源集团罗田平坦原抽水蓄能有限公司黄冈438000 武汉大学水利水电学院武汉430072

硬质岩隧洞的轮廓成型效果对提高围岩稳定性和降低支护成本具有重要意义。以优化隧洞轮廓孔单孔装药量和装药结构为目标,首先,理论分析了隧洞爆破中轮廓孔装药参数的取值范围;其次,分别以1200 g、900 g、750 g、600 g的单孔装药量进行... 详细信息

硬质岩隧洞的轮廓成型效果对提高围岩稳定性和降低支护成本具有重要意义。以优化隧洞轮廓孔单孔装药量和装药结构为目标,首先,理论分析了隧洞爆破中轮廓孔装药参数的取值范围;其次,分别以1200 g、900 g、750 g、600 g的单孔装药量进行了硬质岩隧洞爆破试验,并借助激光扫描仪对隧洞轮廓成型效果进行了扫描分析;最后,利用断裂力学模型分析了不同单孔装药量的隧洞轮廓成型效果。结果表明:当硬质岩隧洞的轮廓孔装药参数在合理范围内时,单孔装药量越小,爆破产生的孔间裂缝数量越少,岩体损伤范围也越小;当装药量由1200 g降低至600 g时,隧洞轮廓超挖体积由6.53 m^(3)降低至2.02 m^(3),但由孔位误差导致的轮廓欠挖体积由0.15 m^(3)增大0.26 m^(3);断裂力学模型在硬质岩隧洞轮廓爆破的模拟中优于损伤模型,模型计算得隧洞轮廓上的半孔数与观察值吻合较好。研究成果可为类似硬质岩隧洞爆破开挖中轮廓成型效果优化提供技术与方法借鉴。

关键词：隧洞爆破轮廓爆破单孔装药量空气间隔装药断裂力学模型

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Development of micro milling force model and cutting parameter optimization

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中国有色金属学会会刊：英文版 2012年第S3期22卷 851-858页

作者： Shih-ming WANG Da-fun CHEN Min-chang jang Shambaljamts TSOOJ Department of Mechanical Engineering Chung Yuan Christian University

Taking the minimum chip thickness effect,cutter deflection,and spindle run-out into account,a micro milling force model and a method to determine the optimal micro milling parameters were *** micro milling force model was derived as a function of the cutting coefficients and the instantaneous projected cutting area that was determined based on the machining parameters and the rotation trajectory of the cutter *** an allowable micro cutter deflection is defined,the maximum allowable cutting force can be *** optimal machining parameters can then be computed based on the cutting force model for better machining efficiency and *** verify the proposed cutting force model and the method to determine the optimal cutting parameters,micro-milling experiments were conducted,and the results show the feasibility and effectiveness of the model and method.

关键词： micro-milling cutting force spindle run out cutter deflection optimal parameter

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环保纤维型钻机刹车块制备及性能评价

化学工程师 2024年第2期38卷 83-86,91页

作者：邱崇粤林世明江毅唐琳中海油能源发展股份有限公司工程技术湛江分公司广东湛江524057 中海油常州涂料化工研究院有限公司上海海铠防腐工程技术分公司广东深圳518052 中海油服油田化学事业部湛江作业公司广东湛江524057 中海油服钻井事业部湛江作业公司广东湛江524057

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,... 详细信息

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,符合行业标准要求,且制动导热温度比石棉型钻机刹车块低,因此,纤维型钻机刹车块性能稳定,使用寿命较长,利于作业人员健康及设备工作效率。

关键词：钻机刹车块冲击强度摩擦性能玻璃纤维石棉

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专用肥用量对油菜籽产量及品质的影响

中国油料作物学报 2024年第2期46卷 359-369页

作者：方雯任涛刘方舟蒋博鲁明星张哲鲁剑巍华中农业大学资源与环境学院/农业农村部长江中下游耕地保育重点实验室/华中农业大学微量元素研究中心湖北武汉430070 湖北省油菜办公室湖北武汉430070 全国农业技术推广服务中心北京100125

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县... 详细信息

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县、沙洋县及洪湖市等3个地点的田间试验,设置了0、450、600、750和900 kg/hm^(2)5个肥料用量,研究不同专用配方肥用量对油菜产量、产量构成因子、养分含量及品质的影响。施用专用配方肥可显著提高单株角果数、每角粒数及千粒重,进而提升油菜籽产量。与不施肥处理相比,专用配方肥施用量为900kg/hm^(2)时,单株角果数、每角粒数及千粒重平均值分别增加277.4%、17.9%和9.2%,油菜籽增产率达300%。油菜专用配方肥的施用显著影响了油菜籽油分及蛋白质含量,与不施肥处理相比,油菜籽蛋白质含量在专用配方肥用量为900 kg/hm^(2)时最高,增长率为16.0%~34.6%,而含油量最低,相较于不施肥降低了4.4%~11.6%。相关性分析表明,增施专用肥显著增加了油菜籽产量、含水率、蛋白质、芥酸及脂肪酸组成,减少了油菜籽硫甙含量。兼顾产量、油菜籽品质和饲用等方面,专用肥用量控制在750~900 kg/hm^(2)时,能够在获得较高的菜籽产量及蛋白质产量的同时,菜籽中硫甙、芥酸及饱和脂肪酸的生成增幅较小并提高了产油量。要在油菜增产的基础上继续追求品质提升,可结合不同地力条件,适量增加中微量元素,以进一步提高油菜籽含油率和改善脂肪酸的组成,实现产量与品质的协同。

关键词：油菜专用肥适宜用量产量品质相关性分析

S-(-)-尼古丁-己二酸盐的制备、特性及其应用研究

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化学研究与应用 2024年第9期36卷 2184-2189页

作者：肖智心李江黄晓江何世波刘明星湖北工业大学生命科学与健康工程学院湖北武汉430068 湖北和诺生物工程股份有限公司湖北恩施445000

S-(-)-尼古丁的获取主要是通过从烟叶等植物中提取,获取途径受限,本研究以2′-羟基尼古丁为原料通过还原、化学拆分制备S-(-)-尼古丁;选用己二酸与S-(-)-尼古丁通过超声法制备S-(-)-尼古丁-己二酸盐,优化了合成工艺。产物利用ESI-MS、^(... 详细信息

S-(-)-尼古丁的获取主要是通过从烟叶等植物中提取,获取途径受限,本研究以2′-羟基尼古丁为原料通过还原、化学拆分制备S-(-)-尼古丁;选用己二酸与S-(-)-尼古丁通过超声法制备S-(-)-尼古丁-己二酸盐,优化了合成工艺。产物利用ESI-MS、^(1)H NMR、HPLC进行表征;采用HPLC进行抗氧化性分析;利用热重分析仪进行热稳定性分析。结果表明在反应的最佳工艺条件下S-(-)-尼古丁总产率达55.1%,比旋光度为-141.5°,光学纯度为99.23%;S-(-)-尼古丁-己二酸盐的产率达94.4%,纯度为99.36%;S-(-)-尼古丁-己二酸盐的抗氧化性和热稳定性均优于S-(-)-尼古丁。本研究提供了一条切实可行的S-(-)-尼古丁及其己二酸盐的合成路线;S-(-)-尼古丁-己二酸盐有效避免了S-(-)-尼古丁易氧化、受热不稳定等不足,具有良好的应用前景。

关键词： S-(-)-尼古丁 S-(-)-尼古丁-己二酸盐抗氧化性热稳定性

Cooperative hunting in a discrete predator-prey system

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International Journal of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow Sophia R-J.jang Hua-ming Wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Department of Mathematics and Statistics Texas Tech University LubbockTX 79409USA Department of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We propose and investigate a discrete-time predator-prey system with cooperative hunting in the predator *** model is constructed from the classical Nicholson-Bailey host-parasitoid system with density dependent growth rate.A sufficient condition based on the model parameters for which both populations can coexist is derived,namely that the predator’s maximal reproductive number exceeds *** study existence of interior steady states and their stability in certain parameter *** is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is *** cooperative hunting,however,may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

关键词： Cooperative hunting discrete predator-prey system predator persistence Neimark-Sacker bifurcation