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81.
In this report, the scientific productivity of Year 2006 of chemical engineering professionals in Taiwan was analyzed carefully with information retrieved from the database of the ISI Web of Science. The distributions of number of authors with x publication versus the number of publication x follows a general power-law trend, which coincidently comply with the Pareto distribution. The power-law indices found ranges from −1.64 to −2.22, which is consistent with values reported in the literature investigated for periods of 1907–1916 and 1969–2004.  相似文献   
82.
本文介绍和评述了化学气相沉积法制备人造金刚石薄膜及其进展。重点评述了反应机理、发展历史、沉积方法、补底材料、检测手段。论述了有利于形成立方晶系金刚石材料的沉积条件。  相似文献   
83.
闫家瑞 《古建园林技术》1988,(18):17-18转21
福禄宫位于湖南长沙市城西区,始建于清代光绪年间。解放后,福禄宫因未及时修理维护,朽损情况严重,1983年底被拆毁。通过对残留木制装修构件拼凑,推算出该建筑的蝼蜂窠部分测绘图。福禄宫蝼蜂窠类似于北方斗栱中的平身科,是一种装饰性构件。福禄宫的昂嘴采用翼龙飞凤交错排列的形式,部分昂嘴端部另加雕饰花板。蝼蜂窠采用层层叠置出踩的形式,其表面只施以桐油或光油等透明涂料,未施其它色漆及彩绘。  相似文献   
84.
巨磁电阻材料的研究与应用   总被引:4,自引:0,他引:4  
介绍了一种新型的磁性功能材料-巨磁电阻材料,综述了其研究进展情况。并就它在巨磁电阻传感器、高密度磁记录读出磁头、巨磁电阻随机存储器以及自旋晶体管等磁电子元器件上的进行了论述。  相似文献   
85.
混凝土抗硫酸盐侵蚀试验的一种新方法   总被引:4,自引:0,他引:4  
欧阳东 《腐蚀与防护》2003,24(9):369-370,375
提出了一个测定混凝土抗硫酸盐侵蚀能力的新方法。采用这种方法对超高强混凝土的抗化学腐蚀性能进行了试验,并和普通混凝土进行了对比。发现用一般硅酸盐水泥配制的超高强混凝土虽然在抵抗化学侵蚀能力方面比普通混凝土有所提高,但由于化学组成上的原因,它对高浓度的(NH4)2SO4等化学介质也难以抵抗。  相似文献   
86.
In the context of the electronic learning (E-learning) methodology, mobile learning (M-learning) focuses on the use of portable technology (such as mobiles or tablets) and the mobility of students. E-learning, and particularly M-learning, can be implemented in combination with other pedagogical methodologies for chemical engineering teaching and learning. We can consider that the vast majority of undergraduates own personal mobile devices nowadays. Moreover, many case studies have shown that M-learning is an effective methodology to capture students’ attention and to actively engage them in the learning process. In most cases, lecturers have reported an improvement in both academic performance and qualifications and have expressed a favourable opinion towards this type of initiative in surveys. In line with the increasing interest in the incorporation of E-learning, this review discusses cases studies based on M-learning within the field of chemical engineering teaching through different technological platforms and apps which can be installed or directly used on mobile devices. All the platforms described in this work offer a free version, emphasizing the possibility of extending this methodology within the university with no need for additional economic resources.  相似文献   
87.
While chemical industrial development in China is growing rapidly, the corresponding safety training resources remain inadequate, which may often lead to increased risk of chemical accidents. These accidents are often associated with the negligence of safety management, poor safety hazard awareness, and lack of safety practice. In order to alleviate these prominent risk factors in chemical industries in China, our study develops a talent training model related to chemical process safety. First, we propose an approach for establishing the “talent training model” related to chemical process safety, consisting of three steps: analyzing the current status and existing problems of talent training related to chemical process safety, determining the theoretical basis and training objectives for developing interdisciplinary talents, and designing a new talent training model. Second, we establish a talent training model using the proposed method, which includes a comprehensive curriculum system, a diversified teaching pattern, and a quintuple evaluation method. Furtherly, we determine the expected outcomes of the talent training model. The research results provide an innovative chemical process safety training method that is applicable nationwide, also it works as a reference for other rapidly developing countries in the chemical process industry to improve safety within the chemical industry.  相似文献   
88.
In the chemical looping with oxygen uncoupling (CLOU) process,CuO is a promising material due to the high oxygen carrier capacity and exothermic reaction in fuel reactor but limited by the low melting point.The combustion rate of carbon is faster than the decoupling rate of oxygen carrier (OC).Hence,high tem-perature tolerance and rapid oxygen release rate of CuO modified by three different ores were investi-gated in this study.The kinetics analysis of oxygen decoupling with Cu-based oxygen carriers was also evaluated.Results showed that CuO modified by chrysolite had faster oxygen release rate than that of CuO.Limestone showed obvious positive effect on the oxidization process.The selected OCs could keep stable in at least 20 cycles,for about 1200 min.Shrinking core model (SCM) fitted well for the decoupling process in the temperature range of 1123-1223 K.Reduction rate kinetic information may aid in the development of chemical looping with oxygen uncoupling (CLOU) technologies during reactor design and process modeling.Ternary doped copper oxide with chrysolite and limestone could improve the reactivity of CuO in decoupling and coupling process and also improve the high temperature tolerance.  相似文献   
89.
Phosphogypsum (PG) is a solid waste produced in the wet process of producing phosphoric acid.Lignite is a kind of promising chemical raw material.However,the high sulfur of lignite limits the utilization of lig-nite as a resource.Based on fluidized bed experiments,the optimal reaction conditions for the production syngas by lignite chemical looping gasification (CLG) with PG as oxygen carrier were studied.The study found that the optimal reaction temperature should not exceed 1123 K;the mole ratio of water vapor to lignite should be about 0.2;the mole ratio of PG oxygen carrier to lignite should be about 0.6.Meanwhile,commercial software Comsol was used to establish a fuel reaction kinetics model.Through computational fluid dynamics (CFD) numerical simulation,the process of reaction in fluidized bed were well captured.The model was based on a two-fluid model and coupled mass transfer,heat transfer and chemical reac-tions.This study showed that the fluidized bed presents a flow structure in which gas and solid coexist.There was a high temperature zone in the middle and lower parts of the fluidized bed.It could be seen from the results of the flow field simulated that the fluidized bed was beneficial to the progress of the gasification reaction.  相似文献   
90.
Chemical looping combustion (CLC) is a clean and efficient flame-free combustion technology,which combust the fuels by lattice oxygen from a solid oxygen carrier with inherent CO2 capture.The develop-ment of oxygen carriers with low cost and high redox performance is crucial to the whole efficiency of CLC process.As the solid by-product from the sulfuric acid production,pyrite cinder presented excellent redox performance as an oxygen carrier in CLC process.The main components in pyrite cinder are Fe2O3,CaSO4,Al2O3 and SiO2 in which Fe2O3 is the active component to provide lattice oxygen.In order to sys-tematic investigate the functions of supports (CaSO4,Al2O3 and SiO2) in pyrite cinder,three oxygen car-riers (Fe2O3-CaSO4,Fe2O3-Al2O3 and Fe2O3-SiO2) were prepared and evaluated in this study.The results showed that Fe2O3-CaSO4 displayed high redox activity and cycling stability in the multiple redox cycles.However,both Fe2O3-Al2O3 and Fe2O3-SiO2 experienced serious deactivation during redox reactions.It indicated that the inert Fe-Si solid solution (Fe2SiO4) was formed in the spent Fe2O3-SiO2 sample,which decreased the oxygen carrying capacity of this sample.The XPS results showed that the oxygen species on the surface of Fe2O3-CaSO4 could be fully recovered after the 20 redox cycles.It can be concluded that CaSO4 is the key to the high redox activity and cycling stability of pyrite cinder.  相似文献   
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