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1.
The results of investigation of the influence of the mechanical, thermal, structural, catalytic, and regenerative characteristics of granular oxide catalysts on the efficiency of decontamination of volatile organic substances in the catalyst unit and of the filtration rate, amount, and concentration of dust, the size of filter particles, the direction and intensity of a magnetic field, and other parameters on the behavior of the particles, the structure, the porosity, the resistance, the optimum fluidization rates, and the efficiency of collection of dust in magnetofluidization of magnetic particles have been given. The diagram and operating principles of a new technology for simultaneous decontamination of volatile organic matter and collection of dust have been presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 77, No. 6, pp. 59–73, November–December, 2004.  相似文献   

2.
研究了不同工艺参数对304不锈钢表面激光熔覆Ni基合金后熔覆层微观组织及硬度、耐磨、耐蚀性能的影响,并寻求最佳激光工艺参数,以期获得冶金结合较好,耐磨、耐蚀性能良好的熔覆层。根据组织与性能的综合分析可知,最优激光工艺参数为激光功率2.5kW、扫描速度4mm/s、送粉速率300mg/s。利用优化工艺参数熔覆后的熔覆层宏观形貌平整、光滑,熔覆层宽度为14.36mm,高度为1.612mm,熔池深度为0.248mm,稀释率为13.33,硬度较高,平均显微硬度为646.4HV,并且耐磨损性能较好,磨损量较低。此外,熔覆层的耐腐蚀性能也较好,自腐蚀电位为-286.77mV。在一定的激光工艺参数下,组织从结合区至熔覆层表层依次为平面晶、胞状晶、柱状晶、树枝晶、等轴晶。激光功率、扫描速度、送粉速率不同,熔覆层中组织粗细变化呈现一定的规律性:随着激光功率的增大,组织由细小逐渐变的粗大;随着扫描速度的增大,组织先变细小,然后变粗大;随着送粉速率的增大,组织逐渐变细小。合金的耐磨性与耐蚀性不仅与组织大小有关,而且与组织物相组成密切相关。  相似文献   

3.
Under the conditions of the plane problem, we propose a new interpretation of boundary conditions in the model problem of elastoplastic equilibrium of a body with linear rigid inclusion whose rupture strength is finite. Stresses in the composite material do not exceed their ultimate values for the materials of the matrix, inclusion, and intermediate contact layer. We studied the two most probable mechanisms of fracture: by exfoliation, i.e., as a result of the propagation of a slip crack along the matrix-fiber interface, and by the rupture of fibers. We established the critical length of the fiber as a function of elastic and strength characteristics of the composite material. If the length of the fiber is greater than critical, the fiber ruptures into two parts; otherwise, the inclusion separates by exfoliation. For each mechanism of local fracture, we determined the ultimate values of external loading.Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 31, No. 4, pp. 60–67, July–August, 1995.  相似文献   

4.
The efficiency and mechanisms of the protective action of a new modification of the KORSOL-1M inhibitor are studied for 20 and Kh 18N10T steels in water with different values of hardness at different temperatures. It is shown that, as a result of the formation of a quasiamorphous film, the inhibiting composition suppresses both the cathode and anode reactions and, therefore, is characterized by the complex mechanism of protection. At elevated temperatures, the protective properties of the inhibitor become somewhat weaker but remain satisfactory for practical applications. In distilled water, the rate of corrosion of 20 steel increases in the presence of the composition. At the same time, for Kh 18N10T steel, the rate of corrosion decreases due to the formation of the passivating film. In water with medium hardness, the protective properties of the inhibitor for stainless steel become weaker. The action of inhibiting composition is characterized by the presence of the aftereffect. Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 33, No. 3, pp. 87–96, May–June, 1997.  相似文献   

5.
This paper describes recent experimental results concerning investigation of the parameters which determine, on the one hand, the kinetics of hydration of tricalcium silicate and the thermodynamic, morphological and structural characteristics of C-S-H and, on the other hand, the evolution of the particle interactions at the origin of setting. It is shown that, in both cases, lime concentration in solution is the most important parameter. As a consequence, the chemical evolution of the system, which controls the lime concentration in solution, determines the nature of particle interactions and the physical evolution of the suspension or paste. In return, the contacts, between particles, resulting from the coagulation of the suspension, seem to have a role in the kinetics of the chemical reaction.  相似文献   

6.
A model of the hardening of a continuum element is presented in the form of finite relationships. The latter formulate the hardening process, dividing it into events, at whose boundary pints the state parameter is varied discretely. By uniting the processes of hardening, unloading, and failure, the constants of the model represent the brittle-plastic nature of the element, its normalized elastic potential, and the value of the reduce strain of the hardening agent.Translated from Problemy Prochnosti, No. 8, pp. 18–21, August, 1990.  相似文献   

7.
In extending the results of [1], a theoretical study is made of the ignition temperature of a nickel-aluminum powder mixture as a function of the power of the external heating source, the dispersity of the refractory component, and the porosity of the powder mixture in the case of a volume reaction. The initial mixture is modeled by a set of spherical elementary cells whose dimension is determined by the range of nickel particle sizes, the mixture composition, and the porosity.Institute of the Physics of Strength and Material Science, Siberian Branch of the Russian Academy of Sciences, Novosibirsk. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 4, pp. 451–454, October, 1993.  相似文献   

8.
汪少烽 《包装工程》2022,43(22):32-46
目的 对劝导式设计的研究现状与实践流程进行对比和分析。方法 以劝导式设计的概念为基础,从劝导式设计的发展脉络、常用模型、应用领域、研究方法、说服策略等层面,对劝导式设计的影响和意义进行探讨。结果 通过梳理主流的8个劝导式设计模型,概括了劝导式设计的理论分支与应用程序。分析劝导式设计的规律和特征,并罗列出劝导式设计对于社会服务、教育培训、政策引导、医疗健康、设计服务流程的先例与积极效益。提出了伦理道德的监管将是未来劝导式设计发展的新挑战与契机。结论 随着互联网、自媒体、大数据与人工智能的发展,传统的话语权将从集中式转为分布式;硬件加内容的服务模式已成为市场的主体,对用户态度与行为的影响将是未来产品与服务的焦点。劝导式设计关注场景定义、用户动机、行为引导、酬劳变量与触发点等因素,为产品研发、服务策略和社会创新提供了有力的理论支撑与实践引导。  相似文献   

9.
Conclusions The standard of the henry is the first (with respect to its approval) state standard in the range of inductance, capacitance, and resistance measurements.This standard served up to the beginning of the sixties as the only initial (computed) quantity, on whose basis the VNIIM determined by indirect means the absolute values of the units of capacitance and resistance. The error of these indirect methods for reproducing units was of the order of 10–5.Investigations, including circulatory international comparisons, of working standards have shown that the precision and accuracy of reproducing inductance units in the USSR are at the level of the best results obtained in national metrological institutes.In recent years new, more precise methods for reproducing resistance units have appeared. These methods, as well as the application of new types of measuring equipment, made it possible to extend substantially the nominal values' range of inductance standards covered by the test schematic.In order to ensure uniformity in this field of measurements, it is necessary to have a set of mutually-related computed inductance and capacitance standards (Fig. 3).The State Committee of standards attached to the USSR Council of Ministers approved, in accordance with the VNIIM recommendations, the coil types PB-1, KB-1, KB-2, and KB-3 as primary state standards of the henry. Prof. Igor' Nikolaevich Krotkov,head of the VNIIM laboratory,was appointed scientific keeper of this State standard.Translated from Izmeritel'naya Tekhnika, No. 10, pp. 7–11, October, 1972.  相似文献   

10.
  On April 21–25, 2008, the Bauman Moscow State Technical University hosted the 10th All-Russia Conference on “Problems and State of Measurements,” which was dedicated to the 140th anniversary of the Faculty of Machine Industry Technologies. It was attended by representatives of colleges: Lomonosov Moscow State University, Zhukovskii VVIA, MAI and Stankin Moscow State Technical Universities, Goryachkin MGAU, Ural (Ekaterinburg), Orel, Perm, Tula, and Penza State Universities, the Russian Academy for the State Service under the Russian Federation President, the Maimond Classical Academy, the Novomoskowsk Institute of the Mendeleev Russian Chemical Engineering University, Kharkov Electronics National University; and also research institutes in the RAS system: the Keldysh Institute of Applied Mechanics, the Lebedev Physics Institute of the Academy of Sciences, the Trapeznikov Institute of Control Problems, the Institute of Psychology, IMASh and the Blagonravov Nizhnii Novgorod branch of IMASh, and IPMASh (St. Petersburg); the Malaya Therapy Institute (Ukraine) and sectoral institutes: the Astrofizika Scientific and Production Association, Snegirev NITI, VNIIMS, NIIizmereniya, Moscow Institute of Expert Evaluation and Testing, LITMAShDETAL’, and the Omskenergoremont OAO PRP. In this number of the journal and the next one, we present a selection of articles from the conference. We also publish a survey article by the chairman of the organizing committee of the conference, Professor M. I. Kiselev. Translated from Izmeritel’naya Tekhnika, No. 10, pp. 3–5, October, 2008.  相似文献   

11.
When characterizing high-temperature fixed points, the fraction of the melting time of the regular part of the plateau with respect to the total melting time, is critical. Maximizing the melting duration minimizes the uncertainty associated with the determination of the fixed-point temperature. One factor that affects this quality is the effect of the thermal bridging between the external and internal surfaces of the ingot enclosed by the cell. This paper presents the results of simulations for the eutectic Pt-C, investigating the effects of different ingot shapes on the duration of the melt plateau. It was found that the formation of a thermal bridge from the rear of the blackbody cavity toward the outer surface of the ingot was critical and that its formation could be delayed or suppressed through a proper choice of the ingot shape. The shapes considered included, firstly, the shape of the rear of the cavity, in contact with the ingot, either cone-shaped or dome-shaped, and secondly, the inside rear surface of the cell, in contact with the ingot, being a cone, a convex dome, or flat. The presence of impurities in the alloy was taken into consideration, and its influence in the evolution of the liquid–solid interface compared with that for the pure alloy. The effect of changing the thermal isolation of the cell, at its front side, was also considered. A dome-shaped surface for the rear of the cavity was found to be more favorable for the development of a regular melting front, in conjunction with the segregation of impurities during melting. At the rear of the cell, a flat surface ensures the back wall is the last to experience thermal bridging, resulting in more extended melting plateaus.  相似文献   

12.
张海林  李冲 《包装工程》2020,41(16):26-30
目的将地区因素引入到城市的文创产品设计中,并建立复杂性分析,提升文创设计水平。在京津冀一体化的基础上,以文创产品为依托,促进地区形象的展现与经济的发展,为文创产品的发展提出参考性建议。方法以京津冀地区特色为主要依据,结合京津冀地区的历史文化,促进地区文化与文创产品的融合与发展。充分发挥京津冀一体化优势,加强各地区文化之间的联系。以具体产品为例,分析其标准、作用、感受等方面的因素。探讨提高文创设计水平的方法。结论通过综合分析文创产品现状,发现京津冀旅游文创产品在发展中的短板,在京津冀一体化发展的基础上,提出对素材的获取、信息的连接及传递等方面的建议。提升地区文创产品水平,进一步有效地提升区域形象带动经济的发展。  相似文献   

13.
为了研究防护层在炸药爆轰过程中对复板表面的保护作用,依据实验数据,分析了复板在焊接完成后的表面平整度、是否发生熔融现象以及金属结合界面的波状纹理的变化情况。防护层隔绝高温的炸药爆轰产物对复板侵蚀,同时在爆轰初始阶段对于应力波透过防护层作用在复板上的应力有明显的增强效应。最终确定在爆炸焊接过程中对复板厚度为0.2cm时,在其表面均匀覆盖一层0.050.15cm的黄油可以较好地保护复板不受高温的爆轰产物侵蚀。实验过程中,选取不同种类炸药进行了对比实验,发现粉状硝铵炸药更加容易装药和控制爆轰速度,本实验选用硝铵炸药完成。  相似文献   

14.
A solution of the problem obtained with the method of integral relations is given here. It is obtained in the form of simple algebraic formulas for the boundaries of the mixing zones on both sides of the jet, the position of the flame front, and the axis of the jet at the end of the initial section. It is found that asymmetry of the boundary conditions has a substantial effect on the characteristics of the jet: the position of the axis of the jet at the end of the initial section can change its sign, depending on the temperature ratio at the boundaries of the jet and for given ratios of the velocity at the boundaries of the jet to the velocity of the jet outflow, the length of the initial section can change several fold.Moscow State Aviation Institute, Moscow, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 68, No. 3, pp. 372–379, May–June, 1995.  相似文献   

15.
It is shown that the measured values of the thermal conductivity of a granular system are substantially affected by the wetting of the grains, the nature of the distribution of the liquid, the conditions of wetting of the grains, and the drying of a layer of grains at a heated wall.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 31, No. 6, pp. 973–980, December, 1976.  相似文献   

16.
李博  徐晓婷  郑雪晴 《材料导报》2018,32(23):4116-4124
近年来,离子液体因具有不易挥发、性质稳定、透光性好、导电率高、可设计性,以及易于在界面处形成双电层等物理化学性质,而展现出广阔的应用潜力和前景,逐渐成为国际科学研究的前沿和热点之一。其中,将离子液体应用于染料敏化太阳能电池(Dye-sensitized solar cells,DSSCs)、钙钛矿太阳能电池和有机光电探测器等有机光电转换器件的研究备受关注。 在有机光电转换器件中,离子液体在染料敏化太阳能电池方面的应用最为广泛且完善。高效DSSCs主要是基于有机溶剂的液态电解质结,但有机溶剂在带来较高光电转换效率的同时,其本身存在的易挥发汽化、光热稳定性差等缺点,导致DSSCs的器件寿命与长期稳定性受到影响,离子液体的引入能有效解决以上问题。此外,离子液体还以电子传输层以及界面修饰层的形式引入,具有高电荷迁移率、低功函数以及高稳定性等优点,能在一定程度上改善器件的短路电流、填充因子和光电转换效率等。因此,离子液体成为在DSSCs的实际应用中兼具性价比高、封装难度低、性能好、稳定性高四大优点的辅助材料。在钙钛矿太阳能电池方面,离子液体的低功函数和高电子迁移率以及一些特殊性质如钝化反应、黏度效应等,都能够实现对电子萃取率、电荷转移电阻、钙钛矿结晶情况等方面的控制以满足实际设计要求,进而有助于钙钛矿太阳能电池的光电转换效率、填充因子等性能指标不同程度的提升。在有机光电探测器方面,引入的离子液体能促使在与之接触的界面处形成双电层,双电层的形成及离子液体的高导电率使得入射光不必照射有机光电探测器上下电极的重叠区域仍旧可以产生较大的光电流输出,从而可以有效摆脱有机光电探测器对电极材料透光性要求的局限性。同时双电层的形成还将促进有机光电探测器工作层中的电荷分离,进一步提高有机光电探测器的响应率。 本文主要从染料敏化太阳能电池、钙钛矿太阳能电池、有机光电探测器三个方面,综述了离子液体在有机光电转换器件中的国内外应用研究进展,就离子液体对提升有机光电转换效率及其实现器件新功能的工作机理进行了详细分析,并对其未来的应用研究方向进行了展望,为今后进一步设计出更适合有机光电转换领域应用的离子液体提供参考。  相似文献   

17.
为了提高大豆蛋白/聚乙烯醇复合薄膜的综合性能,以薄膜的拉伸强度、断裂伸长率、透光率、吸水率为主要评价指标,通过引入隶属度函数综合评价薄膜性能,研究了谷氨酰胺转氨酶TG-B对大豆蛋白/聚乙烯醇复合薄膜性能的影响.试验结果表明:TG-B的添加质量分数、反应pH、成膜温度对薄膜性能的影响较大,当TG-B的添加质量分数为1.0%,反应pH值为6.0,成膜温度为50 ℃时,大豆蛋白/聚乙烯醇复合薄膜的综合性能最优;在此条件下,薄膜的抗张强度、断裂伸长率、透光率和吸水率分别为8.26 MPa, 53.80%,16.23%和67.76%,与未添加TG-B的空白对照相比,其抗张强度、断裂伸长率、透光率分别提高了75.4%,162.9%,27.2%,吸水率降低了25.6%.  相似文献   

18.
Review Room-temperature reactions in thin metal couples   总被引:1,自引:0,他引:1  
Results of a 40 year-long investigation of room-temperature formation of compounds in 144 thin-film couples obtained by combining 23 metals (Ag, Al, Au, Bi, Cd, Co, Cr, Cu, Ga, Ge, In, Mg, Mn, Ni, Pb, Pd, Pt, Sb, Sm, Sn, Te, Ti, Zn) are presented. The data from published papers of the present and other authors have been complemented by unpublished data of the present authors. The systematized results and their analysis point to the following. In 39 couples, a total of 65 compounds are formed. The reactions of compound formation last from 1 min to 10 y, depending on the specimen type and procedure of film deposition. In the bulk–film specimens, the number of compounds formed is smaller and the reaction is slower than in the film–film specimens prepared by thermal evaporation. In the specimens with the sputtered top layer, a greater number of compounds is formed and the compound formation reaction proceeds more rapidly than in the couples prepared by thermal evaporation of both metals. The compounds formed can be transformed into others containing higher percentage of one of the constituents, until the specimen contains an excess of that constituent, provided that such compounds exist in the respective phase diagram. At the beginning of the reaction, compounds are formed in a broad concentration range, while at the reaction end the range is narrowed down, becoming close to that in the corresponding phase diagram. The optimum conditions for compound formation exist in the couples consisting of a high-melting metal and a low-melting one, provided that the potential compound is not high-melting. If the potential compound is high-melting, or if both metals in the couple have melting points in the same temperature range, no compound formation takes place at room temperature. In the couples consisting of a given high-melting metal and one of the low-melting metals, a linear relationship exists between the interdiffusion coefficient and the melting point of the low-melting metal. If, for a couple consisting of a high-melting metal and a low-melting one, there is a solid solubility range of the low-melting metal, during the course of long ageing, the compound formed is decomposed and the low-melting metal is amorphized. During the long ageing, the ambient atmosphere acts on the metal films (alone or in a couple) leading to formation of oxides, hydroxides or carbonates. The results obtained complement the low-temperature range results in the respective phase diagrams.  相似文献   

19.
安全气囊     
安全气囊是现代汽车上最引入注目的新技术装置之一。安全气囊系统主要包括传感器的总成,充气,点火器,折叠气囊,故态氨,警告灯等。当汽的车前方受到一定角度内的高速碰撞时,装在车前部的碰撞传感器和汽车中部的安全传感器,就能够检测到汽车突然减速,并将这一信号在O.01秒内的速度传给安全气囊系统的控制电脑。在电脑经过分析确认之后,立即引爆气囊内的电热点火器(即电雷管),使其发生引爆。这一过程一般只需005秒。点火器引爆之后,固态氮粒迅速气化,大量的氨气化,大量氮气立即吹胀气囊,并在强大的冲击力之下气囊冲开方向盘上的盖而安全展开。主要研究内容有安全气囊的作用,安全气囊的组成以及安全气囊的工作原理。  相似文献   

20.
目的 研究不同轧辊尺寸对40Cr/Q345双金属复合环件热辗扩成形过程的影响规律,并分析环件在辗扩变形过程中内、外层区域的协调变形机理,使辗扩完成后的双金属环件整体变形和温度分布趋于均匀。方法 基于ABAQUS有限元模拟软件,使用动态显式算法,建立双金属环件径-轴向轧制三维热-力耦合有限元模型,采用直径为70、90、110、130、150、170 mm的芯辊尺寸和直径为400、500、600、700、800 mm的驱动辊尺寸,分别研究两个主要的成形辊尺寸对双金属环件热辗扩成形过程的影响。结果 在研究的轧辊尺寸范围内,随着芯辊直径的减小,双金属环件整体温度分布趋于均匀,其变形均匀性明显提高,其中,环件外层40Cr金属塑性变形明显降低,内层Q345金属塑性变形显著升高;随着驱动辊直径的增大,环件整体温度分布均匀性有所降低,变形均匀性略有提高。结论 在双金属环件热辗扩成形过程中,较小的芯辊尺寸能够提高环件整体的温度分布均匀性,并能有效提高内层Q345金属的塑性变形程度,使环件整体变形更加均匀。较大的驱动辊尺寸会略微降低环件的温度分布均匀性,并通过改变内、外层金属的塑性变形程度使环件整体变形趋...  相似文献   

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