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1.
锆和锆合金在化工设备中的应用   总被引:2,自引:0,他引:2  
周耀 《化工设计》2003,13(4):19-22,33
介绍锆和锆合金的性能及在设计、制造、检验中的特点。  相似文献   

2.
氧化锆及其电熔复合耐火原料   总被引:6,自引:2,他引:4  
本文对氧化锆的性能、制法、用途等作了比较完整和系统的叙述,并对其电熔复合耐火原料作了简单介绍。  相似文献   

3.
仇冬 《能源化工》2021,42(6):26-31
制备了不同锆含量的甲醇合成催化剂,对催化剂进行了XRD、H2-TPR、活性评价与选择性分析,开展了条件试验,并与工业上在用的其他同类型甲醇合成催化剂进行了性能对比,结果表明:助剂锆的加入可以与Cu互换形成共同体沉淀盐,有效分散活性单元Cu/ZnO共同体,提高催化剂的比表面积和Cu的分散度,从而提高催化剂的性能.但助剂的引入还会导致活性中间相含量下降,引起催化剂活性下降,确定了助剂锆的最佳含量.MJ型甲醇合成催化剂在活性、选择性、热稳定性等方面已达到或超过工业上在用的其他同类型甲醇合成催化剂产品.  相似文献   

4.
为提高铝锆碳耐火材料的性能,研究了烧成温度对铝锆碳耐火材料气孔率、体积密度、常温耐压强度的影响,得出了适宜的烧成温度范围和最佳的锆莫来石加入量,并对此进行了理论分析。同时,还研究了烧成温度对材料抗氧化性的影响。  相似文献   

5.
锆基陶瓷色料的制备及其性能   总被引:4,自引:0,他引:4       下载免费PDF全文
本文论述了锆基陶瓷色料的制备工艺过程,矿化剂的作用机理以及着色离子在ZrSiO4晶体结构中的价态、取位,为获得性能稳定、呈色效果好的锆基陶瓷色料提供理论指导。  相似文献   

6.
锆基陶瓷色料的制备及其性能   总被引:4,自引:0,他引:4  
张强  周学东 《陶瓷》2000,(5):21-24
文章论述了锆基陶瓷色料的制备工艺过程,矿化剂的作用机理以及着色离子在ZrSiO4晶体结构中的价态、取位,为获得性能稳定、呈色效果好的锆基陶瓷色料提供了理论指导。  相似文献   

7.
肖春  王睿  王玲玲  张玲 《炭素技术》2011,30(4):18-21
对锆含量为2.18%的掺杂型沥青流变性能进行研究。结果表明:含锆沥青黏度随温度的上升而降低,在不同的温度段降低幅度不同;含锆沥青黏度随剪切速率的变化在200℃下表现为牛顿流体到非牛顿流体的变化特征,250℃下则表现为非牛顿流体到牛顿流体的变化特征。在现有掺杂含量下,含锆沥青黏度高于基础沥青,其黏性流动活化能与基础沥青相当。  相似文献   

8.
张强  周学东 《山东陶瓷》2000,23(3):18-20
本文论述了锆基陶瓷色料的制备工艺过程,矿化剂的作用机理以及着色离子在ZrSiO4晶体结构中的价态、取位。为获得性能稳定、呈色效果好的锆基陶瓷色料提供理论指导。  相似文献   

9.
张强  周学东 《陶瓷工程》2000,34(5):14-16
论述了锆基陶瓷色料的制备工艺过程,矿化剂的作用机理以及着色离子在ZrSiO4晶体结构中的价态,取位运行为获得性能稳定、呈色效果好的锆基陶瓷色料提供理论指导。  相似文献   

10.
刘得利 《佛山陶瓷》2001,1(9):19-20
概述了锆质陶瓷的性能和用途,较详细地介绍了一种锆质陶瓷的生产工艺。  相似文献   

11.
2,3,6-三甲基苯酚一步氧化制备2,3,5-三甲基-1,4-苯醌相对于传统的磺化-氧化法具有产品收率高、过程简单、条件温和以及环境友好等特点。本文针对2,3,6-三甲基苯酚一步氧化制备2,3,5-三甲基-1,4-苯醌的均相催化氧化和非均相催化氧化工艺进行了综述,对两种工艺的发展过程及研究现状进行了评价及总结。详细讨论了不同方法和路线在催化活性、选择性以及产品分离和催化剂回收等方面的优缺点,简要分析并总结了2,3,6-三甲基苯酚一步氧化研究的发展规律和最新动态,展望了以非均相催化反应机制为重点的微观机理研究和以提高催化剂循环稳定性、降低制备成本为重点的工业化探索两个潜在的发展方向。  相似文献   

12.
Biosorption may be simply defined as the removal of substances from solution by biological material. Such substances can be organic and inorganic, and in gaseous, soluble or insoluble forms. Biosorption is a physico‐chemical process and includes such mechanisms as absorption, adsorption, ion exchange, surface complexation and precipitation. Biosorption is a property of both living and dead organisms (and their components) and has been heralded as a promising biotechnology for pollutant removal from solution, and/or pollutant recovery, for a number of years, because of its efficiency, simplicity, analogous operation to conventional ion exchange technology, and availability of biomass. Most biosorption studies have carried out on microbial systems, chiefly bacteria, microalgae and fungi, and with toxic metals and radionuclides, including actinides like uranium and thorium. However, practically all biological material has an affinity for metal species and a considerable amount of other research exists with macroalgae (seaweeds) as well as plant and animal biomass, waste organic sludges, and many other wastes or derived bio‐products. While most biosorption research concerns metals and related substances, including radionuclides, the term is now applied to particulates and all manner of organic substances as well. However, despite continuing dramatic increases in published research on biosorption, there has been little or no exploitation in an industrial context. This article critically reviews aspects of biosorption research regarding the benefits, disadvantages, and future potential of biosorption as an industrial process, the rationale, scope and scientific value of biosorption research, and the significance of biosorption in other waste treatment processes and in the environment. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
振动丝法测定常压和加压下液体的黏度和密度   总被引:5,自引:0,他引:5       下载免费PDF全文
马沛生  周清  杨长生  夏淑倩 《化工学报》2004,55(10):1608-1613
介绍了自行研制的高温高压振动丝黏度密度仪的构造和测定原理,并以正戊烷作为实验流体对仪器的可靠性和准确性进行了测试.测定了环己烷在323.15~413.15 K温度范围内、正辛烷在313.15~393.15 K温度范围内、苯在303.15~445.15 K温度范围内压力分别为常压和6.10 MPa、正庚烷和异辛烷在298.15~403.15 K温度范围内压力分别为常压和5.10 MPa下的黏度与密度,并分别对不同压力下的黏度、密度数据进行了关联.  相似文献   

14.
将木质素作为一种有机颗粒填料添加到热塑性塑料中,可解决造纸黑液资源化利用、石油原料日渐紧张以及环境污染加剧等严峻问题。而木质素与热塑性塑料之间相容性直接影响木质素在塑料工业中的应用与发展。首先简要概述了木质素结构与性质和木质素/热塑性塑料复合材料的性能分析,然后系统地阐述国内外研究木质素/热塑性塑料复合材料界面增容方法及其原理;增容方法按添加相容剂、改性木质素和改性塑料进行归类,并对3种增容方法进行比较分析;接着综述了木质素复合材料中增容方法的交叉复合使用;最后对未来木质素/热塑性塑料复合材料界面增容的研究方向以及思路进行了展望。  相似文献   

15.
Chlorophyll pigments present in canola seed, meal and crude and degummed oils were analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. Chlorophylls a and b, low levels of pheophytin a, and occasionally traces of pheophorbide and its methyl ester were present in canola seed. Meals and oils contained magnesium-deficient chlorophyll pigments such as pheophorbide a, methylpheophorbide a, pheophytins a and b, and pyropheophytins a and b but not chlorophyll a or b. The amounts of chlorophyll pigments were oil > seed >> meal. Both crude and degummed oils contained pheophytin a and pyropheophytin a as main components, but the ratio of pyropheophytin a to pheophytin a was markedly higher in degummed oils. No pheophorbides were detected in degummed oils. These results suggest that oil processing steps such as extraction and degumming affect the composition of chlorophyll pigments. Publication No. 678 Canadian Grain Commission.  相似文献   

16.
A review of the literature is presented for the hydrolysis of alkoxysilane esters and for the condensation of silanols in solution or with surfaces. Studies using mono-, di-, and trifunctional silane esters and silanols with different alkyl substituents are used to discuss the steric and electronic effects of alkyl substitution on the reaction rates and kinetics. The influences of acids, bases, pH, solvent, and temperature on the reaction kinetics are examined. Using these rate data, Taft equations and Bronsted plots are constructed and then used to discuss the mechanisms for acid and base-catalyzed hydrolysis of silane esters and condensation of silanols. Practical implications for using organofunctional silane esters and silanols in industrial applications are presented.  相似文献   

17.
塑料挤出机螺杆,机筒耐磨损,耐腐蚀的强化与应用   总被引:4,自引:0,他引:4  
李金钊 《中国塑料》1999,13(9):83-88
对塑料挤出机,注塑机螺杆,机筒的磨损,腐蚀原因及提高螺杆,机筒耐磨损,耐腐蚀的方法、制造与应用作了较详尽的介绍。  相似文献   

18.
工业生产中物位测量的探讨与研究   总被引:4,自引:0,他引:4  
在工业生产中常常会遇到常温,常压和一般介质的液位,料位和界面的测量,也会遇到高温,高压,易燃易爆,腐蚀性较强的液位,料位和界面的测量。在工业生产中物位测量有接触式和非接触式测量。但应根据生产工况及技术要求来合理选用。  相似文献   

19.
Dryer design requires food properties, drying rate and mass-heat transfer coefficients. These values change continuously during drying due to changes in food fractions, particularly the water fraction. The high energy demand and costs allied to inefficient devices, creates a great need for new processing equipment. Along these guide-lines, several heat pump drying research projects were established at the Norwegian University of Science and Technology. The heat pump dryer provides high quality final product as its drying conditions can be controlled. Its efficiency and non-polluting operation come from closed air-refrigerant circuits and from its ability to fully recover the latent heat of moist air as it exits the drying chamber. Most of the above features are quite the opposite of the conventional dryer characteristics. Several experiments were made on heat pump drying of fruits and roots at temperatures from -22.5 to 40°C to obtain data and correlations on thermophysical properties, specific enthalpy and rehydration. Also, tests were done on drying rate, moisture content, drying constant, effective mass diffusivity and heat and mass transfer equations. The next important phase is the development of a simulation model to predict the performance and characteristics of the heat pump dryer plant. The objectives of the present work are to develop and lo test a heat pump dryer simulation model. The simulation provides results on the characteristics of both plant and components which are integrated by heat and mass transfer equations. The program has menus with click-on icons, input and output pop-up dialogue boxes. The usual commands such as, file-open, file-save, edit-delete are available in this program simply called Hpdryer. The model contains moist air psychrometric. natural and conventional refrigerant property libraries. Ammonia is a time-tested, self-alarming and natural refrigerant. It has been used extensively in the past, and it has better thermodynamic and transport properties than halocarbons. Safety is easily attained by design and its restrictive standards have helped increase its use in several countries. There are 36 ammonia installations in Norway and in the United Kingdom, including a drying plant. Ammonia has zero Odp, zero Gwp and the recent R&D has led to viable small-sale heat pump plants. Ammonia and dichlarodifluoromethane refrigerants were used in the test cases simulated by Hpdryer madel.  相似文献   

20.
Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After surgery to implant a device, adjacent cells interact with the implant and release molecular signals that result in attraction, infiltration of the tissue, and attachment to the implant of various cell types including monocytes, macrophages, and platelets. These cells release additional signaling molecules (chemokines and cytokines) that recruit tissue repair cells to the device site. Some implants fail and require additional revision surgery that is traumatic for the patient and expensive for the payer. This review examines the literature for evidence to support the possibility that fibronectins and BMPs could be coated on the implants as part of the manufacturing process so that the proteins could be released into the tissue surrounding the implant and improve the rate of successful implantation.  相似文献   

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