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71.
为提高硅砖的成品率和性能指标,进一步降低产品能耗,研究了硅砖生产过程中容易影响制品性能和成品率的关键环节和设备,并参考国内外先进技术,研发出原料除铁工艺及添加剂、矿化剂自动添加系统,确定了优质硅砖生产线相应环节的最佳技术方案,最大限度地提高了成品质量并降低能耗。  相似文献   
72.
王伟  燕山 《橡胶工业》2014,61(2):107-110
采用Abaqus有限元分析软件,综合考虑12R22.5全钢载重子午线轮胎的实际结构并引入轮胎-轮辋、轮胎-地面的接触非线性边界条件,建立轮胎的有限元分析模型,对轮胎进行静负荷仿真分析,得到轮胎负荷与下沉量的关系及接地印痕和压力分布。与试验对比表明,模拟与试验结果吻合得很好。  相似文献   
73.
采用缓慢蒸发溶剂的方法,在去离子水中合成了单核Mn(Ⅱ)配合物[Mn(phen)2(H2O)2]·(H2O)6·SO4(phen=1,10-邻菲罗啉)。利用X射线单晶衍射和元素分析等表征手段确定了其结构和组成。该配合物属于三斜晶系,空间群为P-1。该配合物的中心离子为Mn(Ⅱ),中心离子与两个1,10-邻菲罗啉和两个水分子配位,在晶胞中还有六个未配位的水分子和一个自由的硫酸根离子。配合物中存在多种结构的氢键,包括平面三角形、四面体形、四边形、五边形和六边形。  相似文献   
74.
In this study, sulfonated poly(ether ether ketone) (SPEEK) was very efficiently crosslinked via a Friedel–Craft reaction using 1,6‐dibromohexane and AlCl3. The resulting crosslinked SPEEK (c‐SPEEK) membranes exhibited improved dimensional stability, thermal and chemical stability, and mechanical strength with slight reduction in the elongation. The methanol permeability was reduced by approximately two orders of magnitude by the crosslinking reaction. The proton conductivities of c‐SPEEK membranes were greater than Nafion‐212 in the temperature range of 30–90°C. Overall, this new crosslinking method can be conveniently and efficiently applicable to most aromatic hydrocarbon polymer membranes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40695.  相似文献   
75.
Polyaniline/tailored carbon nanotubes composite (PANI/TCN) synthesized via situ polymerization of aniline monomer in the presence of tailored carbon nanotubes (TCN) is reported as electrode material for supercapacitors. The morphology, structure, and thermostability of the composite were characterized by scanning electron microscope, Fourier transform infrared, and thermogravimetric analysis. The electrochemical property of the resulting material was systematically studied using cyclic voltammetry and galvanostatic charge–discharge. The results show that the short rod‐like PANI dispersed well in the TCN with three‐dimensional network structure. The as‐prepared composite shows high specific capacitance and good cycling stability. A specific capacitance of 373.5 F g?1 at a current density of 0.5 A g?1 was achieved, which is much higher than that of pure PANI (324 F g?1). Meanwhile, the composite retains 61.7% capacity after 1000 cycles at a scan rate of 50 mV s?1. The enhanced specific capacitance and capacity retention indicates the potential of composite as a promising supercapacitor electrode material. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39971.  相似文献   
76.
Thermoresponsive graft copolymers of ε‐caprolactone and N‐isopropylacrylamide were synthesized by a combination of ring‐opening polymerization and the sequential atom transfer radical polymerization (ATRP). The copolymer composition, chemical structure, and the self‐assembled structure were characterized. The graft length and density of the copolymers were well controlled by varying the feed ratio of monomer to initiator and the fraction of chlorides along PCL backbone, which is acting as the macroinitiator for ATRP. In aqueous solution, PCL‐g‐PNIPAAm can assemble into the spherical micelles which comprise of the biodegradable hydrophobic PCL core and thermoresponsive hydrophilic PNIPAAm corona. The critical micelle concentrations of PCL‐g‐PNIPAAm were determined under the range of 6.4–23.4 mg/L, which increases with the PNIPAAm content increasing. The mean hydrodynamic diameters of PCL‐g‐PNIPAAm micelles depend strongly on the graft length and density of the PNIPAAm segment, allowing to tune the particle size within a wide range. Additionally, the PCL‐g‐PNIPAAm micelles exhibit thermosensitive properties and aggregate when the temperature is above the lower critical solution temperature. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41115.  相似文献   
77.
Undecenoic acid functionalized thermo/pH responsive microgels, poly(N‐vinylcaprolactam‐co‐undecenoic acid) [poly(VCL‐co‐UA)], were synthesized by precipitation emulsion copolymerization. The microgels exhibit reversible thermo/pH responsive phase transition behavior, which can be tuned by varying the monomer feed ratio. The lower critical solution temperatures (LCSTs) of the materials are close to body temperature. As a result, when temperatures rise above ca. 37°C, a rapid thermal gelation process occurs, accompanied by a phase transition, resulting in expulsion of encapsulated compound. In vitro experiment evaluated its applicability as a drug carrier for controlled release of an anticancer agent (doxorubicin) and showed that the drug encapsulation efficiency (EE), releasing rate, and kinetics are dependent on the temperature and pH value as expected. Minimal cytotoxicity of the microgels was observed by a cytotoxicity assay using 3T3 fibroblast cells. Our finding suggests that the poly(VCL‐co‐UA) based microgels may be considered a promising candidate for temperature or pH‐controlled delivery of anticancer drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41146.  相似文献   
78.
The polyvinylpyrrolidone (PVP)/poly(vinylidene fluoride) (PVDF) core–shell nanofiber mats with superhydrophobic surface have been prepared via electrospinning its homogeneous blending solutions, and the formation of the core–shell structure was achieved by the thermal induced phase separation assisted with the low surface tension of PVDF. The electrospinnability of the blending solutions was also investigated by varying the blending ratio of the PVP and PVDF, and it enhanced with the increase of PVP content. SEM and TEM results showed that the fibers size was varied in the range of 100 nm–600 nm with smooth surface and core–shell structure. The composition of the shell layer was determined by the XPS analysis, and further confirmed by water contact angle (WCA) testing. As the fraction of PVDF exceeding PVP in the electrospinning solutions, the nanofiber mats showed superhydrophobic property with the WCA above 120°. It indicated that the PVDF was concentrated in the shell layer of the fibers. X-Ray diffraction (XRD) and attenuated total reflection infrared spectroscopy (ATR-IR) analysis indicated that the PVDF was aggregated with the β-phase crystallite as dominant crystallite. The nanofiber mats with the gas breathability and watertightness ability due to the porous structure and superhydrophobic would be potential applied in wound healing.  相似文献   
79.
Near-net-shaped hierarchical structure-adjustable short mullite fibers/mullite whiskers frameworks (MF/MW frameworks) were prepared by slurry-filtration and heat-treating method. The main structure of MF/MW framework was constituted by lap-jointed mullite fibers. Every single fiber in the framework was densely covered by mullite whiskers which formed through fluorine-catalyzed gas-phase reaction, and the fibers actually served as curved substrates for the mullite whiskers' growth. The lap-jointing points of the fibers were served by movable intersected mullite whiskers. Moreover, the microstructure of the frameworks could be adjusted by tailoring the raw materials mass ratio. The volume densities, the apparent porosities and the thermal conductivities of the MF/MW frameworks in different raw materials mass ratios were 0.459–0.487 g/cm3, 79.7–82.8% and 0.1356–0.1965 W/k m, respectively. The compression–resilience property of the samples was tested under 0.4 MPa at room temperature. The compression ratio and resilience ratio of the MF/MW frameworks in different raw materials mass ratios were 1.63–2.25% and 92.67–98.16%, respectively. The MF/MW frameworks with advanced thermal and mechanical properties were considered to be promising high-temperature heat-insulation material.  相似文献   
80.
油田在生产开发过程中产生了大量采油污水,经处理回注地层是采出水的最优出路。文章首先分析了油田采出水的特点,然后重点介绍了传统与新兴的油田采出水回注处理技术的研究与应用进程,并对油田采出水回注处理技术下一阶段的研究与发展方向进行了展望。  相似文献   
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