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排序方式: 共有4829条查询结果,搜索用时 15 毫秒
1.
《Ceramics International》2022,48(17):24953-24964
2.
This paper mainly focuses on the development of pressure tracking control logic of electro-hydraulic actuators for vehicle application. This is done to improve and ensure the performance of a precise lower-level controller for evolving modern shift control logic. The required performance is obtained by hysteresis model-based feed-forward control and additional feedback control. The hysteresis and the time delay, which adversely affect pressure control, are well known nonlinear behaviors in electro-hydraulic actuators. In order to cope with the hysteresis, a novel hysteresis model is proposed based on a physical phenomenon. A mathematical model based on a characteristic curve obtained in preliminary experiments is presented using only one tuning parameter, and this model can be inverted easily to construct a feed-forward controller. In addition, a feedback controller is designed considering the stability margin of a time delay system. The feedback control inputs ensure compensation of the feed-forward errors caused by model error and uncertainty. The proposed controller is designed to lower computational cost considering applicability for production vehicles. As a result, the developed pressure controller is applied to a transmission control unit of a production vehicle and verified experimentally for various driving scenarios. 相似文献
3.
4.
微表处技术是一种性能优良的路面养护技术。首先检验了微表处用原材料的技术指标,在满足规范的要求下选择了三种不同级配,并对三种不同级配的微表处混和料的使用性能进行了比较。 相似文献
5.
G Garrote J
M Cruz H Domínguez J
C Paraj 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(4):392-398
Non‐isothermal processing of lignocellulosic materials in aqueous media (autohydrolysis reaction) under mild conditions leads to solutions containing valuable chemicals (oligosaccharides, sugars and acetic acid) and other, undesired, compounds (belonging to the extractive and acid‐soluble lignin fractions) which have to be removed in further purification treatments. Liquors obtained by non‐isothermal autohydrolysis of Eucalyptus globulus wood and corncobs under a variety of operational conditions were extracted with ethyl acetate in order to remove non‐saccharide components, and the suitability of the fraction dissolved in the organic phase was assayed for possible utilisation as an antioxidant. The yield and antioxidant activity of ethyl acetate extracts (measured by the α,α‐diphenyl‐β‐picrylhydrazyl (DPPH) radical scavenging capacity) showed a strong dependence on the autohydrolysis conditions. The antioxidant activity of extracts obtained under selected operational conditions compared well with synthetic antioxidants. © 2003 Society of Chemical Industry 相似文献
6.
采用全因素试验法,对马尾松木材进行过热乙醇溶液脱脂处理,以获取马尾松木材高效脱脂工艺技术。试验结果显示:(1)脱脂温度对马尾松松脂溶出量的影响极显著,且溶出量随着脱脂温度的升高而增大;(2)脱脂时间对马尾松松脂溶出量的影响极显著,且溶出量随着脱脂时间的延长呈先增大后减小的趋势;(3)脱脂浴比对马尾松松脂溶出量的影响极显著,且溶出量随着脱脂浴比的延长呈先增大后减小的趋势;(4)利用过热乙醇溶液对马尾松木材进行脱脂,其最佳工艺是脱脂时间为130℃、脱脂时间为8h、浴比1:8。 相似文献
7.
This study describes a laboratory method for the estimation of emission from preservative-treated wood in the different situations where emissions could enter the environment for use classes 3 (not in contact with ground) and 4 and 5 (in contact with the ground, fresh water or sea water) according to OECD Guidelines. Samples of scotch pine sapwood (Pinus sylvestris L.) were treated with CCA (1% and 2%), ACQ-1900 (3% and 7%), ACQ-2200 (2%), Tanalith E 3491 (2% and 2.8%), and Wolmanit CX-8 (2%). 相似文献
8.
John E. Sohn 《The Journal of Adhesion》1985,19(1):15-27
Enhanced matrix-filler adhesion is realized after filler treatment with a surface treatment process. The hydrosol/coupling agent treatment was applied to a wide range of inorganic and organic fillers, and adhesion to a variety of matrix resins was improved. Scanning Electron Microscopy (SEM) was used to determine the locus of failure in the filled systems. The locus of failure shows the relative degree of adhesion between the filler and the polymer matrix. Significant improvement in adhesion in humid environments is also observed. 相似文献
9.
Makikazu Takehana Tomomichi Nishino Katsuyasu Sugawara Takuo Sugawara 《Korean Journal of Chemical Engineering》1996,13(5):538-543
Cobalt-, praseodymium-added zinc oxide varistor was prepared through a wet chemical method followed by sintering with or without
calcination. Changes in grain size, compact density, additives distribution, and voltagecurrent/ capacitance-voltage relations
were investigated for the characterization of the samples sintered at temperatures from 1473 to 1573 K without calcination
or with calcination at 773 K for 2 h. The electrical properties were compared with nhose of samples prepared by two types
of ball mill methods. The wet chemical method provided almost the same additives-distribution profile and less impurities
in comparison with the ball grinding method carried out for 10–100 h. The donor concentration and the potential-barrier height
for the samples were evaluated by Double Schottky Barrier Model. Addition of small amount of both cobalt and praseodymium
in preparation by the wet chemical method was effective for a better nonlinearity relation between voltage and current, which
has potential for a smaller sized varistor. 相似文献
10.
湿法生产线的技术更新改造有异地新建新型干法生产线和原地改成湿磨干法生产线二种。浙江虎山集团(?)3.0 m×88.68 m湿法线的改造,经方案比较和生产原料的状况,采用了湿磨干烧方案。其中,料浆脱水采用了真空吸滤法,浇成系统采用了南京院专有技术。改造投产后,获得了优质、高产、低耗和安全生产的技改效果。 相似文献