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1.
搅拌流化床搅拌功率研究   总被引:3,自引:0,他引:3  
根据在粉体中运动物体受力分析 ,对几种不同型式搅拌桨功率准数表达式进行了推导 ,并对搅拌流化床中的功率准数与通气速率和搅拌速度进行了关联 ,关联结果与实验值吻合较好。  相似文献   

2.
搅拌过滤机   总被引:1,自引:0,他引:1  
<正> 美国捷哥公司生产一种可变速,正、反转的动力搅拌过滤机。该机有压力/真空两种功能,不锈钢体及Hastelloy 过滤器,设备齐全、性能良好,在控制的条件下,可以加工易碎及热敏材料。机器分两部分,上部带有搅  相似文献   

3.
搅拌装置     
<正> 文章根据搅拌的目的,简述了搅拌槽的操作工况条件,槽的材质等等。然后,又分析了具有代表性的各类搅拌叶片,搅拌槽内的夹套结构,传热部件,槽内壁的加工方法,设备的放大,设备的强度,机能,寿命以及  相似文献   

4.
搅拌球磨机     
刘浩斌 《陶瓷》1990,(4):24-27
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5.
搅拌过滤器     
<正> 该搅拌过滤器集过滤与干燥于一体,用于处理药品、精细化工产品以及其它脆弱性物料。其利用的是吸滤原理,包括压力搅拌、洗涤和增稠,并根据需要置有固定的底部或可移动的底部,以及计算机控制或手动控制。该过滤器的内过滤面积为0.38—15.19  相似文献   

6.
压缩空气搅拌与机械搅拌混凝的比较   总被引:3,自引:0,他引:3  
针对压缩空气搅拌混凝工艺在污水处理上的广泛应用,用模型试验来确定压缩空气搅拌反应的最优条件;通过该模型试验与机械搅拌下的烧杯试验进行比较,对试验结果进行分析得出两类搅拌方式的优缺点。试验结果表明,空气搅拌试验三阶段的最优反应条件为混合时间、一级反应时间和二级反应时间分别为1,3和5min,曝气量为0.4,0.04和0.02m3/h。在空气搅拌试验的混合阶段,大的曝气量并没有改善出水的剩余浊度。空气搅拌试验在混凝时间、药剂用量上具有优势,但在沉淀性能上机械搅拌要优于空气搅拌。与烧杯试验相比,该模型试验对压缩空气搅拌混凝工艺的工程设计与生产运行更有针对性。  相似文献   

7.
金涛 《云南化工》1994,(4):39-41
在对一卧式搅拌釜搅拌功率的设计计算中,比较了各种功率计算方法,并与实测值进行对照。  相似文献   

8.
泛能式搅拌桨搅拌特性研究   总被引:1,自引:1,他引:0  
在直径为 2 4 0mm的搅拌釜内 ,考察了泛能式搅拌桨的功率、传热特性 ,混合实验在直径为 386mm的搅拌釜中进行。在层流域内 ,建立了功率准数Np 与桨几何尺寸及雷诺准数Re的关联式 ;得到了努塞尔准数Nu与桨几何尺寸、雷诺准数Re、普朗特准数Pr以及体系粘度的关系 ,并采用单位质量流体表示的雷诺准数εD4/ν3 取代雷诺准数关联 ,误差均在 10 %以内。在中低粘度区内相同功耗下 ,泛能式桨的传热系数明显高于螺带桨。当Re >3时 ,泛能式桨的混合效率比双螺带桨要高。  相似文献   

9.
据称,这种新型快速搅拌机可适用于液体、固体、粉料、磨料、腐蚀料及粘性材料等,尤其适用于釉料的搅拌。该搅拌机的特点:可用或不用旋转平台,具有一对定予和转子,可保证制品的予分散、  相似文献   

10.
叶片转子型搅拌器是一种新型搅拌装置。七十年代初期,国外才开始应用。近年来国外已有定型产品供应市场。这种搅拌器与普通搅拌器相比,在结构上有根本的改革。其优点是:物料混合均匀、有研磨作用、搅拌效率高、作业时间短和节省电能。  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

13.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

14.
Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  相似文献   

15.
A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by 1H MAS NMR. For direct comparison purposes, an SiO2 coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N2 absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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