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1.
在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响。对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸为直径21 mm的时候模具翘曲表现更好。  相似文献   

2.
The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.  相似文献   

3.
In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.  相似文献   

4.
浅谈设备的性能与操作对胎面压出质量的影响   总被引:1,自引:0,他引:1  
简要介绍了胎面压出的工作原理及工艺过程,对设备的配置及操作对胎面压出质量的影响进行了分析,并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。  相似文献   

5.
In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.  相似文献   

6.
郭伟  郭晓镭  吴跃  黄斌  龚欣 《煤化工》2011,39(5):9-11,14
针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。  相似文献   

7.
We consider the process of fracture of a solid celestial body with a certain strength entering a planetary atmosphere. Using an integral approach in fracture mechanics, we show that the process of fragmentation of a meteorite occurs in several stages and is completed when the maximum value of the aerodynamic drag is reached. The characteristic size of the fragments formed depends on the properties of the meteorite material. At the end of fragmentation, the stage of rapid deceleration of the fragments begins: “pumping” the energy of the meteorite into a shock wave. The proposed technique is illustrated using the examples of the interaction of the Tunguska meteorite with the Earth's atmosphere and the interaction of Comet Shoemaker—Levy with Jupiter's atmosphere. All-Union Scientific Research Institute of Experimental Physics, Sarov 607200. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 6, pp. 117–124, November–December, 1995.  相似文献   

8.
A hyperbolic equation (wave model) was used to take into account the relaxation character of mass transfer at the simulation of the diffusion stage of the formation of GRIN lenses. The results of the calculations are presented in accordance with wave and classic models.  相似文献   

9.
Cotton cellulose was chemically modified by introducing acrylamide, acrylonitrile and carboxyalkyl moieties in the form of groups or polymers. In carbamylethylated, cyanoethylated and carboxymethylated cotton, these moieties are in monomeric groups, whereas, in graft copolymers of cotton cellulose with acrylamide, acrylonitrile or acrylic acid, the moieties are in polymeric forms. These substrates were dyed independently using direct, acid, basic or reactive dyes. Results showed that at roughly equal nitrogen content, polyacrylamide–cotton graft copolymer exhibited a much higher colour strength than carbamylethylated cotton when the two substrates were dyed using basic dye. The opposite is the case for direct and reactive dyes. The acid dye produced comparable colour strengths. Similar trends were observed when the other samples were dyed with these four dyes. The results were explained in terms of microstructural changes in the physical and chemical structure of cotton caused by the etherification and grafting reactions.  相似文献   

10.
高汉华 《塑料制造》2006,(11):32-34
组合凹模的应力分析是一个非常复杂的问题,对其进行精确分析是解决模具寿命的关键。本文采用有限元分析软件Ansys对转子的组合凹模进行了分析,为转子组合凹模的优化设计提供了依据。  相似文献   

11.
Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO4) dopants. The results of DSC and FT-IR indicate the Li+ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment Tg and the soft-segment Tm influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.  相似文献   

12.
王德强  袁源 《煤化工》2014,(3):31-34
以气煤、肥煤、焦煤、瘦煤为样煤,进行了样煤的粉碎、有机溶剂溶胀和硝酸氧化处理,考察了处理后煤样中的药用腐植酸得率。结果表明,吡啶和N,N-二甲基吡咯烷酮是溶胀较好的溶剂;样煤粉碎后,随着粒度的减小,煤的溶胀率增加;粒度粉碎至200目的气、肥煤经吡啶溶胀和硝酸氧化后,煤样的药用腐植酸得率可达到73.0%和71.4%,而经甲醇溶胀和硝酸氧化的200目气煤药用腐植酸得率为56.4%和58.4%。实验结果表明,煤样经过溶胀和硝酸氧化处理,对药用腐植酸的提取有促进作用。  相似文献   

13.
浅谈我国陶瓷产品出口反倾销数据动态预警系统的构建   总被引:1,自引:0,他引:1  
本文首先从我国陶瓷产品贸易现状出发,阐述了建立我国陶瓷产品出口反倾销数据动态预警系统的意义,然后指出建立我国陶瓷产品出口反倾销数据动态预警系统的总体思路,并在此基础上论述建立我国陶瓷产品出口反倾销数据动态分析预警系统的主要步骤。  相似文献   

14.
The effect of the hugh-temperature (800–1000°C) treatment in air of the Cr2O3/Al2O3 catalyst, which contained 18Cr2O3 + 0.4Na+, wt % and was prepared under laboratory conditions with the use of Pural SB1 grade high-purity pseudoboehmite, on the variation in the phase composition of the catalyst, specific surface, and catalytic characteristics in the dehydrogenation reaction of n-butane (yield and selectivity by ΣC4 olefins and 1,3-butadiene, conversion of n-butane) was investigated depending on the calcination temperature of the catalyst. It is shown that thermal stability depends on the following main factors: the method preparation of catalysts, the phase composition of the starting aluminum hydroxide, carrier texture, and the presence of modifying additions and impurities of other metals. In the case of the same chemical composition of the catalyst, the samples obtained by the wet mixing of pseudoboehmite with an aqueous solution of chromic anhydride are most thermally stable compared with the impregnation samples. It is established that the addition of cerium improves the thermal stability and activity of the impregnation Al-Cr catalyst, while the impurity of the Fe3+ ions (up to 0.1 wt %) does not worsen these characteristics. The investigated samples of the catalyst are more thermally stable than the imported industrial catalyst, which loses activity and specific surface after calcination at 900–1000°C. The determination of the thermal stability of fresh catalysts and the factors affecting it can be used as the preliminary evaluation of the future lifetime of catalysts.  相似文献   

15.
Conclusions It has been established that the increased wear of the silica refractory parts (concrete blocks and brick) in the soaking pit walls of the 1150 slabbing mill is caused by chemical interaction of the iron-manganese slag containing the aggressive intermetallic phase FexAly with the silica lining with the formation of low-viscosity molten material.The type of steel has a significant influence on the wear of the lining. The most aggressive are killed and semikilled steels, which in contrast to rimmed steels are deoxidized with aluminum.The structure of refractories has a definite influence. The more dense dinas parts, which possess a strong tridymite bond of the crystals in the finely dispersed portion, are more wear resistant than the silica concrete blocks not containing tridymite.Testing of refractory concrete parts of magnesia spinellide or forsterite compositions in the walls (or only in the support zone) of soaking pits with liquid slag removal is recommended.Translated from Ogneupory, No. 3, pp. 42–46, March, 1986.  相似文献   

16.
Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage and on the width at half maximum of the current-overvoltage curve is studied. A number of the approximate expressions for the density of states, the tunnel current and the width are obtained in the fully adiabatic limit for different particular cases. It is shown that at small values of the coupling of the electronic levels of the electrodes with the valence orbital of the redox molecule and the small values of the bias voltage two regions of the reorganization Gibbs energy exist with different dependence of the width on the reorganization Gibbs energy. The results of calculations of the density of states, the tunnel current and the width are presented and used for the interpretation of the experimental data [N.G. Tao, Phys. Rev. Lett. 76 (1996) 4066, I. Visoly-Fisher, K. Daie, Y. Terazono, C. Herrero, F. Fungo, L. Otero, E. Durantini, J.J. Silber, L. Sereno, D. Gust, T.A. Moore, A.L. Moore, S.M. Lindsay, PNAS 103 (2006) 8686].  相似文献   

17.
This paper considers the mechanisms involved in the effect of the unconnected porosity of the condensed phase of nitrocellulose propellants on the linear burning rate with a pressure rise. A model based on experimental data is proposed for the variation in the linear burning rate taking into account the compaction of the fuel cells resulting in a nonlinear dependence of the burning rate on pressure. The temperature coefficient of the linear burning rate is found to exhibit a nontrivial behavior under pressure rise conditions in various ranges of initial temperatures. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 5, pp. 58–63, September–October, 2008.  相似文献   

18.
邰茉  胡盼  王靖涛 《化工进展》2018,37(8):3067-3075
流体流动诱导微胶囊膜起皱和变形是一个普遍存在的现象。针对这一现象已有一些模拟和实验研究,但是对于微通道内不同因素对于微胶囊褶皱情况的影响以及褶皱的存在对于微胶囊实际膜面积和粒径的影响等方面却鲜有探讨。针对这一问题,本文制备了具有褶皱膜的聚酰胺微胶囊,并提出通过溶剂浸泡法将微胶囊膜褶皱伸展开,以分析微胶囊的实际膜面积和实际粒径。同时,定义了褶皱度的概念,将抽象的褶皱情况数值化,使分析更为方便。最终,通过研究分析发现,由于与流体剪切力正相关,流体流量和黏度的增大会导致微胶囊褶皱度增加;当这两者固定时,微胶囊粒径的改变对其褶皱度基本无影响。在应用方面,微胶囊壁面褶皱情况的分析为制备单核双壁式微胶囊提供了一种新思路。  相似文献   

19.
研究了浮选柱浮选法对锶的浮选。考察了在锶最优浮选条件下浮选柱的高度、直径、布气室、微孔发泡器型号及柱形变化对浮选柱浮选法的影响。通过实验可知,浮选柱直径、发泡器、布气室、球型浮选柱都对锶的浮选率都有很大的影响;而浮选柱高度对浮选率的影响不大,但是在相同条件下,合适浮选柱高度可以缩短浮选时间;当选择合适的尺寸和球形柱,锶的浮选率最高可以达到97%。  相似文献   

20.
首先介绍了国内外复合材料行业使用的填料氢氧化铝的发展趋势;其次介绍了带式真空过滤机在国内外发展及应用的概况,并对其工作原理做了陈述。最后叙述了其在种分玛瑙生产线上的应用情况、存在问题及解决方法。  相似文献   

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