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81.
ZF公司面向中国的高性能变速器 总被引：1，自引：0，他引：1
文章介绍了ZF公司为轮式装载机特别研发的WG系列高性能变速器,其产品系列可覆盖9-30吨级的车辆.ZF高性能的动力换档变速器具有简单和坚固的零部件设计、采用精确调整轴承、整体式壳体结构和优越的电控系统等优点. 相似文献
82.
There is an advantage for users of electrospray and nanospray mass spectrometry to have an understanding of the processes involved in the conversion of the ions present in the solution to ions in the gas phase. The following processes are considered: Creation of charge droplets at the capillary tip; Electrical potentials required and possibility of gas discharges; Evolution of charged droplets, due to solvent evaporation and Coulomb explosions, to very small droplets that are the precursors of the gas phase ions; Production of gas phase ions from these droplets via the Ion Evaporation and Charge residue models; Analytical uses of ESIMS of small ions, qualitative and quantitative analysis; Effects of the ESI mechanism on the analysis of proteins and protein complexes; Determination of stability constants of protein complexes; Role of additives such as ammonium acetate on the observed mass spectra. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:898–917, 2009 相似文献
83.
Dr. Katja Neubauer Udo Lubenau Christine Hecker Prof. Dr. Bernhard Lücke Dr. Dietmar Paschek Dr. Sebastian Wohlrab 《化学，工程师，技术》2013,85(5):713-722
The depletion of higher alkanes from methane is a key aspect during the conditioning of natural gases or accompanying gases. Membrane technologies could be used as alternative to energy and cost intensive purifications. Against this background the influence of membrane geometry, composition of the gas mixture as well as temperature and pressure was investigated in separation experiments for methane/n‐butane mixtures using MFI membranes. 相似文献
84.
Mohammad Reza Saeb Hadi Ramezani‐Dakhel Hossein Ali Khonakdar Gert Heinrich Udo Wagenknecht 《应用聚合物科学杂志》2013,127(6):4241-4250
After‐hatching eggshell (AHES) nanobiofiller and nanocalcium carbonate (nano‐CA) were separately added to various elastomers, such as acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), and natural rubber (NR), in various amounts of 5, 10, and 15 phr. The effect of particle size and dispersion of such nanofillers on thermomechanical properties and curing characteristics were then investigated. The ultimate tensile properties of SBR and NR nanocomposites were improved to some extent when 5 phr of AHES nanofiller was added to the rubber compound compared to CA. In the case of NBR nanocompounds, however, the mechanical properties were seemingly comparable, irrespective of the type of nanofiller. This contradictive behavior could be attributed to the alteration of crosslink density due to particular filler–matrix interaction while using mineral and natural fillers. The results of the rheometric study revealed that using AHES rather than CA slightly increases the scorch time of all types of prepared nanocomposites, whereas a significant drop in the optimum curing time was seen for NBR nanocomposites containing AHES biofiller. Moreover, thermogravimetric analysis showed similar thermal stability for SBR nanocomposites containing AHES and CA fillers. Finer particle size of CA and higher porosity of AHES at high and low loading levels were respectively the main reasons for improvement of ultimate properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
85.
86.
Abstract 2,6‐Di(5,6‐dipropyl‐1,2,4‐triazin‐3‐yl)pyridine (BTP) extracts trivalent actinides from nitric acid with high separation factors over the lanthanides. The kinetics of americium(III) extraction and back extraction of this extraction system was studied in a constant‐interface stirred cell. The americium(III) extraction rate was found to be independent of the stirring speed. This means that the rate of mass transfer is limited by a slow chemical complexation reaction (“chemical regime”). The americium(III) extraction rate was found to increase linearly with BTP concentration. Nitric acid concentration had a strong influence on the rate of the americium(III) extraction, due to its influence on the free extractant concentration. The addition of ammonium nitrate did not affect the rate of americium(III) extraction. By investigating the influence of the interfacial area on the americium(III) extraction rate, the interface was identified as the site of the chemical reaction. The americium(III) back extraction rate increased linearly with the stirring speed, indicating that the back extraction is limited by diffusion. The extraction and the back extraction rates could be calculated by a simple model based on equilibrium data for the co‐extraction of americium(III) and nitric acid. 相似文献
87.
Mohammad Reza Saeb Mehdi Moghri Hossein Ali Khonakdar Udo Wagenknecht Gert Heinrich 《乙烯基与添加剂工艺杂志》2013,19(3):168-176
The influence of the type and content of organically modified nanoclay (NC) and the amount of calcium stearate (Ca.St) on the fusion characteristics of a poly(vinyl chloride) (PVC) nanocomposite was studied by using response surface methodology. To interpret the fusion behavior, different PVC/NC compounds were prepared in a Plasticorder with a constant rotor speed of 60 rpm while keeping the processing time and temperature constant. The results revealed that introducing NC particles into the PVC compound resulted in an increase in the maximum torque (MAT), while the minimum torque (MIT) declined. On the contrary, both the MAT and MIT values slightly increased with increasing Ca.St content. It was also found that with increasing NC content, the fusion time increased and the fusion factor decreased, whereas increasing the Ca.St lowered the fusion time. Furthermore, the difference between the MIT and MAT values demonstrated multifarious behaviors depending on the material type. Ultimately, a correlation was established between the material characteristics and the fusion factor of the PVC nanocompounds. J. VINYL ADDIT. TECHNOL., 19:168‐176, 2013. © 2013 Society of Plastics Engineers 相似文献
88.
Valrie Grumel Robert Brüll Harald Pasch Helgard G. Raubenheimer Ron Sanderson Udo M. Wahner 《大分子材料与工程》2002,287(8):559-564
1‐Pentene was polymerized with the syndiospecific catalyst system i‐PrC(Cp)(9‐fluorenyl)ZrCl2/MAO. The molar mass of the resulting polymers depends strongly on the reaction temperature and decreases from M̄w = 126 000 at 0°C to M̄w = 46 000 at 100°C, but is more or less independent of the monomer and the MAO concentration. The influence of reaction temperature and concentrations of MAO and monomer on the type of end‐groups generated during the chain termination, as well as on the type of stereoerror, was investigated. The degree of tacticity was dependent on the polymerization temperature with [rrrr] > 0.99 at 0°C and [rrrr] = 0.75 at 100°C. 相似文献
89.
Klaus Bauckhage Udo Fritsching Hubertus Lohner Peter Schreckenberg Volker Uhlenwinkel Dirk Bergmann 《化学，工程师，技术》2001,73(4):304-313
The production capacities of plants for metal pulverisation are frequently rated according to the minimum throughput of melt flowing from the distributor crucible to pulverisation. Especially in the case of high‐melting point metals and their alloys deficiencies occur in the thermal balance of the crucible in the exit section as a result of gas expansion at the pulverisation gas jets, which act as heat sinks. Minimum throughputs and associated limiting values of the convective heat transfer of the melt are stipulated in order to prevent \"freezing\" (solidification of the melt) in the crucible. The pertinent situation is illustrated for copper and steel melts and technical possibilities for compensating for heat deficiencies by inductive heating of the distributor exit are presented. In addition, the demand for minimum throughputs can be abandoned, and there result possibilities of scaling‐down and energy conservation as well as improvement of powder discharge. 相似文献
90.
The main objectives of integrated approaches to environmental protection in industrial processes are cost reduction and a reduction of environmental impact. Environmental protection measures should be integrated into the innovation processes since it is during the development stage that some 80% of the overall costs arise. Substantial potential for such innovation exists in the chemical industry, especially in the field of fine chemicals. The substitution of traditional chemical industrial procedures by biotechnological methods appears particularly promising. For example, the use of enzymes (extremozymes) or fermentative methods has much to offer. Estimation of the benefits of such procedures critically depends on information instruments such as eco‐balances in combination with analysis of economic efficiency. Since such instruments are not consistent in their approach and application, further considerations concerning the amalgamation are required. 相似文献