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Search Results: 1 - 10 of 26053 matches for " 彭问安 "
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纳米氢氧化钙根管充填材料的制备及其生物相容性 Preparation of Nanometer Calcium Hydroxide Root Canal Filling Materials and Their Biocompatibility
王籽明,孙青,杨柳,邱韵,颜然,问安,范伟
- , 2018,
Abstract: 目的:探讨纳米氢氧化钙根管充填材料的制备及其生物功能性和安全性。方法:改良制备纳米氢氧化钙的装置,以CaCl_2和NaOH为沉淀反应物,聚乙二醇为改性剂,超声波为辅助振动,正丁醇共沸蒸馏法干燥分散制得纳米氢氧化钙粉体,将粉体与医用碘仿和甘油调制成适合临床根管治疗要求根充糊剂,对制备粉体进行表征和葡萄糖微渗漏检测,以及与人体红细胞反应的溶血状况。结果:本实验搭建的制备装置自动化程度高,隔菌防尘,明显缩短制备时间,节省了人力和物力;本方法能够制备出具有明显氢氧化钙和聚乙二醇特征吸收波峰,粒径在100-200nm,大小均匀分散,符合临床根管治疗要求的纳米氢氧化钙;充填糊剂能够显著防止微渗漏发生,在使用初期几乎没有微渗漏发生,随时间延长,微渗漏值增加并不明显,与临床上常规使用的氢氧化钙根充糊剂Vitapex比较,在相同时间段,其防止葡萄糖微渗漏值显著减小,在第28天,葡萄糖微渗漏值为(2.09±0.89)mmol/L显著低于Vitapex的(5.04±0.98)mmol/L(P<0.01)。纳米氢氧化钙根管充填材料使红细胞结构完整,不引起红细胞破裂而溶血,其造成血红蛋白含量的相对值明显低于阳性对照组(P<0.01),溶血率为4.41%,显著低于医用置入材料引起红细胞溶血率允许范围。结论:本实验改良的制备装置科学合理,制备的粉体为纳米级、分散均匀的氢氧化钙,作为根充材料具有显著防止微渗漏作用和不引起溶血的生物安全性,是一种值得开发的新型、具有发展前途的纳米充填材料
纳米氢氧化钙制备方法的改良及作为根管治疗糊剂的生物安全性初探
Modification of Preparation Method of Nanometer Calcium Hydroxide and Preliminary Assessment of Biological Safety for Root Canal Therapy.

王籽明, 问安, 孙青, 范伟
WANG Zi-ming
, PENG Wen-an, SUN Qing, FAN Wei

- , 2018, DOI: 10.13701/j.cnki.kqyxyj.2018.04.021
Abstract: 摘要 目的:改良纳米氢氧化钙的制备方法并对其作为根管治疗糊剂的生物安全性进行初步评价。方法:以CaCl2和NaOH为沉淀反应物,改良环节包括纳米氢氧化钙的制备系统,改性剂用聚乙二醇,加快反应速度为超声波振动,干燥分散纳米粉体为正丁醇共沸蒸馏干燥法。实验样品制得后分别选用红外线光谱仪、透射电子显微镜检测其组成成分和粒径大小,再将样品与医用碘仿和甘油调制成符合临床根管治疗要求糊剂,用扫描电子显微镜检测其形貌。后将实验分为阴性、阳性对照组和纳米氢氧化钙糊剂组,观察各组红细胞溶血反应及溶血率。结果:改良后制备装置自动化程度更高,操作更准确、安全, 能防尘、隔菌,显著缩短制备时间,节省人力和能源,降低成本,制备的粉体颗粒更分散、均匀,不发生软硬团聚。样品由聚乙二醇和氢氧化钙组成,粒径大约在100~200 nm之间,呈球形和链球形。作为根管治疗糊剂,其表面致密、光滑,横截面积大、呈六方体结构,颗粒间隙小,排列紧凑、致密;与阳性对照组比较,纳米氢氧化钙糊剂组不引起溶血反应,其血红蛋白相对值明显低于阳性对照组(P<0.01),溶血率为4.54%,显著小于医用植入材料要求红细胞溶血率≤5。结论:本实验改良方法科学合理,其表征为纳米级、分散均匀而无团聚的氢氧化钙,作为根管治疗糊剂初步证实具有生物安全性,值得在临床上推广和开发、具有广泛发展前途
基于FPGA视频图像采集及显示系统的设计与实现
Design and Implementation of a Video Image Capture and Display System Based on FPGA
 [PDF]


Computer Science and Application (CSA) , 2014, DOI: 10.12677/CSA.2014.41004
Abstract:
针对图像处理实时性要求高的领域利用最新的可编程片上系统技术设计并实现了基于可编程逻辑器件FPGA的视频图像采集及显示系统系统以NIOS II软核为主控制器将图像采集图像处理及存储图像显示等功能集成在单片可编程逻辑器件FPGA实现了实时视频图像的采集处理及显示实验结果表明系统有着易于移植便于针对特定应用定制成本大幅降低等优势具有较高的工程应用与参考价值
For the high-demand field of real-time image processing, this system designs and implements a video image acquisition and display system based on FPGA using the latest system-on-programmable-chip technology. It is based on the NIOS II core controller, and integrates the image acquisition, image processing and storage, image display function on a single programmable logic device FPGA. The experimental results show that the system is easy to transplant, convenient for custom specific application, greatly reduces the cost and provides an important reference for other similar designs.
分布式光伏电源并网对电网电压影响的仿真建模
The Simulation Modeling of the Impact of Distributed Photovoltaic Power Grid Connection on Grid Voltage
 [PDF]


Smart Grid (SG) , 2015, DOI: 10.12677/SG.2015.55026
Abstract:
分布式光伏发电是光伏发电的重要发展方向,但光伏电源的输出特性使得其并网会对配电网的电压产生一定影响。本文从分布式光伏电源的原理和发展出发,介绍了光伏发电在未来能源利用方面的重要地位,简要叙述了光伏发电系统及发电原理,就光伏发电系统的分类、组成做出了归类,并对当前光伏发电系统研究热门的两大方向,即集中式并网光伏发电系统和分布式并网光伏发电系统的特点进行了说明。然后重点分析了光伏电源的等效模型,研究了光伏电源并网对配电网电压影响的仿真模型的建立,并搭建了基于通用的IEEE 34节点配电网模型及其参数的Matlab/Simulink光伏并网仿真平台,为探究光伏电源并网对配电网电压影响规律建立了模型基础。
Distributed photovoltaic power generation is an important developing direction of photovoltaic power generation. But the output characteristic of photovoltaic (pv) power has certain influence on the voltage of the distribution network. Firstly, this paper introduces the photovoltaic energy’s role in the future, and briefly introduces the principle of photovoltaic power generation system and power generation. Secondly, the centralized grid connection photovoltaic power generation system and distributed grid connection photovoltaic power generation system which are current research focuses of photovoltaic power generation system are discussed. Then the equivalent simulation model of photovoltaic power source is analyzed. Thirdly, the matlab simulation model is built based on the general IEEE 34 nodes distribution network model and parameters. Finally, this paper analyzes the influence on power grid voltage under the condition of different interconnected locations and various capacities of photovoltaic power.
交直流并行线路雷击时电磁暂态仿真研究
Investigation on the Electromagnetic Transient for AC/DC Parallel Line during Lightning Fault
 [PDF]


Smart Grid (SG) , 2015, DOI: 10.12677/SG.2015.55027
Abstract:
为了节约资源和环境保护,我国特高压输电线路将形成大容量多回输电线路、交直流并行的格局。雷击是特高压线路跳闸的主要原因,论文搭建了交直流并行输电线仿真模型,对线路遭受雷击时的电磁暂态进行了仿真分析。首先采用PSCAD仿真软件建立了特高压直流输电工程的仿真模型,建立了特高压交直流并行输电线路模型。基于以上模型对雷击特高压直流线路进行了暂态仿真,分析了参数的暂态变化。结果表明线路电压与电流均迅速上升,两极各项参数发生了畸变和振荡。
In order to save resources and protect the environment, the power grid of China will have more multiple-circuit transmission lines and high capacity AC/DC parallel transmission lines. This paper builds the simulation model of AC/DC parallel transmission lines and studies the transient process of transmission lines when lightning, which is one of the main reasons of line fault. The electromagnetic transient simulation software PSCAD/EMTDC is employed to establish the simu-lation model of UHV DC model, and the AC/DC parallel transmission model is also set up. Based on the model established above, we simulate the transient simulation of lightning striking on the DC lines and AC lines, and parameters’ changes are analyzed. It turns out that the voltage and current of the transmission lines will rise abruptly when the lightning happens and many parameters of DC lines will have strong distortion and oscillation.
熔融石英材料的色散与棱镜对的色散补偿
The Dispersion Characteristic of the Fused Quartz and the Dispersion Compensation of the Prism Pair
 [PDF]


Applied Physics (APP) , 2016, DOI: 10.12677/APP.2016.67019
Abstract:
本文从电偶极振子模型出发,运用塞尔迈耶公式,计算出从紫外至近红外波段熔融石英材料的二阶与三阶色散值。受激发射占主导作用使激光晶体在其增益峰的长波侧表现为正的二阶色散值。采用棱镜对来获得二阶负色散是色散补偿的简单易行的方法。研究了二阶色散完全补偿时熔融石英棱镜对的设计,得到了棱镜的顶角及两棱镜顶之间距离的表达式。
The Group Velocity Dispersion (GVD) and the Third Order Dispersion (TOD) of the fused quartz are calculated by adopting the Sellmeier-formula from the electric dipole resonance model. The stimulated radiation has dominating effect on the GVD of a laser crystal, thus a positive GVD will usually come forth when the work wavelength locates in the longer side of a Gain Mountain. For dispersion compensation, to apply a prism pair is a simple and convenient means to get negative GVD. The design of the prism pair of the fused quartz is researched, and the apex angle and the distance from an apex to another apex of prisms are expressed.
对比zara,阿迪王式的中国山寨营销初探
The Marketing Exploration of Shanzhai Garments, Exemplified by Adivon in the Comparison of Zara
 [PDF]

家乐
Modern Marketing (MOM) , 2012, DOI: 10.12677/mom.2012.21003
Abstract: 近年山寨经济近年在中国取得了迅猛发展,服装行业尤以阿迪王为例,尽管近年来阿迪王的网络知名度越来越高,但是和国际大牌zara相比,仍是有很大的差距。随着近年来对消费者价值的提倡,本文采用问卷分析和二手资料相结合的方法,同时结合深入访谈阿迪王品牌总监的资料,从营销理论4C角度入手,将中国服装行业典型山寨企业阿迪王和国际知名山寨品牌zara进行对比,进而发现中国式的山寨需要在保持低价多款的优势下,从质量入手重塑品牌形象,赋予品牌一定的内涵。同时要有以顾客为中心的4C营销理念,并将之贯彻到企业日常运营,以此才可获得长远发展。
The economy phenomenon of shanzhainowadays has developed a lot in recent years, especia- llyadivon in garments industry. Although it is much known in internet now, we can also see that compared with the international brand zara, it still has a big gap. As nowadays society call more for the consumer value, this paper will base on the questionnaire analysis, second-hand data research and depth interview with adi- vion’s brand manager, andsee from the 4C angle marketing theory to compare the Chinese shanzhai adi- von, which is typical in garments industry, with the international famous brand zara. And the paper found that the Chinese shanzhai garments need to change their brand image, give some content to the brand in the premises that it keeps its advantage of cheap prices and various style. Also, it should have the 4C marketing concept, which is focus on consumer and implement it into the real practice. Only by this can the shanzhai really have a consistent development.
发展生态经济,促进湿地保护—以西洞庭湖自然保护区为例
Development of Ecological Economy, Accelerate Wetland Conservation—The case study on West Dongting Lake Nature Reserve
 [PDF]

平波
Sustainable Development (SD) , 2013, DOI: 10.12677/SD.2013.32007
Abstract: 西洞庭湖自然保护区自成立以来,充分运用生态经济学原理和系统工程方法来改变自然保护区内生产和消费方式,本文阐述了西洞庭湖自然保护区在生态系统承载能力范围内,充分利用湿地资源大力发展生态旅游和有机渔业生产等生态经济,有力地促进了湿地生态环境的保护,并对今后发展湿地生态经济提出了合理建议。Since established, the West Dongting Lake Nature Reserve has taken full advantage of ecological economics theories and system engineering methods to change the production and consumption patterns. This article expounds that the West Dongting Lake Nature Reserve makes the best of the wetland resources to develop ecological economy, such as ecological tourism, Organic Fisheries and so on within the ecological capacities, and effectively promotes the protection of the ecological environment, and offers reasonable proposals for the future development of the wetland ecological economy.
日本文化模式与中国之借鉴
The Cultural Pattern of Japan and the Significance for Our Country
 [PDF]

刘少东, 婷婷
Open Journal of Historical Studies (OJHS) , 2013, DOI: 10.12677/OJHS.2013.12003
Abstract:

一个民族的民族性是通过其文化来反映的。在全球化的趋势之下,国际竞争通过各种方式表现,要想在世界上保持民族特色,自立自强,应当有着自己独具特色的民族文化。日本在发展其自身文化的过程中,善于通过吸收外来文化塑造本国文化,这对于我国现今面临的文化发展出路问题具有很大的借鉴意义。
The national character of a certain nation manifests itself through its culture. According to the trend of globalization, the competition among countries presents in various ways. A country should possess its unique national culture in order to maintain the distinctive national features and keep self-reliance on the world stage. In the process of developing the culture, Japan is adept in assimilating the external culture to set up its own culture, which provides the referential significance for our country’s problem of cultural development.

城镇化建设过程中的农村远期电力负荷预测研究
Research on Long-Term Power Load Forecasting at Rural Areas during Urbanization Process
 [PDF]

英杰, 律方成
Transmission and Distribution Engineering and Technology (TDET) , 2014, DOI: 10.12677/TDET.2014.32003
Abstract:

电力负荷预测是电网规划的基础,其水平的高低将直接影响电网规划质量的优劣。随着我国城镇化建设的推进,电力负荷预测的复杂性进一步加深。为满足农村地区城镇化建设对电力负荷预测的要求,适应长期可持续发展的需要,本文分析了城镇化建设过程中农村电力负荷预测所面临的诸多新老问题,对现有的空间负荷预测方法进行了改进,并以河北某县为应用实例,针对该县在城镇化建设过程中的实际情况,对其电力负荷进行了预测及校核。研究结果对我国城镇化建设中的农村地区配电网规划具有重要的参考和指导意义。
Power load forecasting is the basis for network planning, which will directly affect the quality of network planning. With the advance of urbanization in China, the complexity of power load forecasting further deepened. To meet power load forecasting requirements and needs of long-term sustainable development at urban areas, the old and new problems about power load forecasting in the process of urbanization in rural areas are analyzed and the existing spatial load forecasting method is improved correspondingly. For the application example, power load of a country in Hebei province was predicted and checked. The research has important implications for reference and guidance in distribution network planning during the urbanization of rural areas.

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