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161.
MITSURU TSUKIMA TAKAYUKI KAI KAZUKI TAKAHASHI TOSHIE TAKEUCHI KENICHI KOYAMA 《Electrical Engineering in Japan》2018,203(1):50-57
We have designed and developed a tri‐stable rotary solenoid actuator, which has a simple structure and simple operation. The plunger has two stabilities at the extreme positions along an angular stroke and the third stability at the center of it. The third has been successively achieved by using the electromagnetic restoring torque, which is designed to be larger than the inertia torque. The dynamic characteristics were determined by utilizing an optimal design program that is specially constructed based on the response surface method in order to design the coil winding and the power supply for the coil excitation. A prototype solenoid was constructed and used to verify the tri‐stable motions and accuracy of the previously constructed design program. 相似文献
162.
163.
细旦有光三角异形涤纶FDY生产工艺探讨 总被引:1,自引:2,他引:1
讨论了影响细旦有光三角异形涤纶FDY的生产和质量的工艺条件。通过适当调整工艺 ,在普通FDY生产线上生产出优质 5 6dtex/3 6f三角特亮涤纶FDY。 相似文献
164.
This article focuses on the assessment and understanding of the mechanism of natural and artificial aging processes of a triple‐layer film made of low‐density polyethylene (LDPE) used as greenhouse cover. The film material contains color dye and ultraviolet–A (UV–A) and infrared (IR) stabilizers and antioxidant. The combined effect of temperature variations and UV–A radiations, of the natural and artificial aging, on the physical properties (free surface energy and yellow color measurements), mechanical behavior (tensile tests), thermal stability (TGA and DSC analysis), and structural stability (FTIR analysis) was investigated. The natural aging was conducted on a greenhouse, located in northern Algeria, over a period of 7 months. However, the artificial aging was performed at four different agricultural greenhouse simulating conditions of temperature and UV–A radiation (namely, at 40°C, 40°C with UV–A, 50°C, and 50°C with UV–A) for periods of aging up to 5486 h (7.6 months). The results revealed that, the maximum loss of the yellow color additives occurs at 2981 h under the natural aging process and at 2440, 1096, 1340, and 121 h under the four artificial aging conditions, respectively. There was an observed increase in the films free surface energy and a significant degradation in the mechanical properties with aging time. This can be correlated with the film material structural changes. The natural aging of the film in North Africa is almost equivalent to artificial aging at 40°C. The concurrent effect of temperature and UV–A radiations induced polymer chains scission leading to faster degradation in the film material and consequently a reduction in its durability and service lifetime. The results show also that the measured parameters are directly related to the limit of use criterion for evaluating the lifespan of agricultural greenhouse LDPE covers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
165.
以含铜离子废水为处理对象,利用一种新合成的三基配位聚合超分子试剂二硫代氨基三聚氰酸钠(TDC),研究了其对废水中铜离子和浊度的去除效果。与无机絮凝剂Al2(SO4)3、聚合氯化铝(PAC)、聚合硫酸铁(PFS)相比较,TDC处理含铜废水具有加药量少,最佳适用pH值低,形成絮体快并且絮体较大,絮体的沉降性能好,不易破碎等特点。TDC对Cu2 的沉淀效率在99%以上,处理后的废水能达到重金属废水的国家一级排放标准。它具有较宽的pH应用范围,在4~13的pH范围内,pH的变化对沉淀效果不受影响,浊度的去除率也在98%以上;在处理具有浊度的含铜废水中,铜离子和致浊物质可相互促进各自的去除;外加絮凝剂的种类对重金属离子的去除率影响不大。 相似文献
166.
高性能含硅、氟甲基丙烯酸酯共聚物的研究 总被引:7,自引:0,他引:7
制备了γ-甲基丙烯酰氧基丙基三(三甲基硅基)硅烷W D、γ-甲基丙烯酰氧基丙基三乙氧基硅烷及其与甲基丙烯酸异冰片酯、甲基丙烯酸异丁酯和含氟甲基丙烯酸酯的共聚物,通过IR、水接触角、吸水率、铅笔硬度和DSC等手段研究了共聚工艺、含氟单体、硅烷单体及催化交联剂对共聚物膜表面性能和力学性能的影响。延迟滴加有机硅单体尤其是W D和含氟单体可使低用量硅氟单体下的共聚物膜表面憎水性大大增强;催化交联剂可使共聚物的玻璃化温度从31.21℃提高到53.12℃,膜的铅笔硬度达到4H以上。 相似文献
167.
Electricity, heating and cooling usage at the same time constitute an important part of primary energy consumption. Currently, intense efforts are being devoted to the improvement and development of new technologies to promote energy savings and to mitigate the global warming. Among these technologies, tri‐generation and poly‐generation systems come into prominence due to their high efficiencies, as well as low operating costs and low greenhouse gas emissions. Nevertheless, modelling and sizing these systems is a large‐sized problem itself, and the higher the number of inputs, the higher the computational complexity. This paper aims to give a comprehensive review of the optimisation techniques used in tri‐generation and poly‐generation systems modelling and optimisation. After having reviewed more than a hundred papers, taxonomy is constructed. Self‐organising map is used to cluster the reviewed studies based on the optimisation techniques. Variations of the energy resources and the outputs of implemented systems are summarised. The crowd of clusters demonstrated the widely used optimisation techniques and the gaps in research. This study will certainly pioneer the optimisation studies in the field of tri‐generation/poly‐generation applications. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
168.
Reactive extraction of 3‐hydroxypropionic acid from model aqueous solutions and real bioconversion media. Comparison with its isomer 2‐hydroxypropionic (lactic) acid
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169.
泡沫级专用三(2-羟乙基)异氰尿酸酯改性蜜胺树脂 总被引:1,自引:0,他引:1
采用三(2-羟乙基)异氰尿酸酯(THEIC)改性蜜胺树脂,通过粘度和力学性能测试研究了改性树脂的聚合工艺条件(如物料配比、反应时间、改性剂添加量、固含量等)对体系聚合反应及改性产物韧性的影响,采用IR光谱对改性树脂的结构进行了表征。结果表明,THEIC参与了反应,植入蜜胺树脂的分子链中,加大了三嗪环之间的距离,起到增韧改性的目的。适合发泡用THEIC改性蜜胺树脂的适宜的工艺条件为:n(M)∶n(F)=1∶2.8,pH=9.0~9.5,反应温度(95±1)℃,时间80~100 min,固体质量分数为75%,THEIC添加量为10%。 相似文献
170.
二异丙基联苯和三异丙基联苯混合物的合成研究 总被引:1,自引:0,他引:1
根据傅 克烷基化反应原理 ,以异丙醇为烷基化试剂 ,超酸作催化剂合成了一种主要含有二异丙基联苯和三异丙基联苯混合物的新型无碳复写纸染料溶剂 ,通过改变反应物配比、催化剂用量、反应温度等条件 ,得到合成二异丙基联苯和三异丙基联苯混合物的合适工艺条件 :反应物配比为 3∶1、催化剂质量分数 (以联苯的质量计 )为 5 0 %、温度为 85~ 90℃。 相似文献