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的阻尼性能进行了研究.考察了聚氯乙烯(PVC),N-环己基-2-苯并噻唑次磺酰胺(CZ)以及过氧化二异丙苯(DCP)对EVM基共混物阻尼性能的影响.实验结果表明,PVC在共混物EVM/EPDM中,与EVM700完全相容,可以显著改善EVM在高温区的阻尼性能.PVC与EVM/NBR共混体系发生部分相容,能显著拓宽有效阻尼温域,高达62.4℃;与BIPB相比,DCP使EVM/NBR的阻尼因子峰得到显著拓宽,有效阻尼温域高达64.9℃.少量的CZ对EVM/NBR=80/20共混物阻尼因子有显著增大和拓宽作用.关键词:乙烯-醋酸乙烯酯橡胶;聚氯乙烯;共混;阻尼;乙丙胶;丁腈胶;......
氧沉淀对直拉硅单晶硬度的影响 杨德仁1,马向阳1,陈加和1,曾徵丹1 (1.浙江大学硅材料国家重点实验室,浙江,杭州,310027) 摘要:研究了氧沉淀对直拉(CZ)硅单晶维氏硬度的影响.研究表明,在发生一定程度氧沉淀的情况下,硅单晶的硬度会由于氧沉淀导致的间隙氧浓度的降低而减小,此时间隙氧原子的固溶强化作用对硅单晶硬度具有显著的影响;而当氧沉淀足够显著时,由于氧沉淀的密度和尺寸较大,氧沉淀在硅单晶中的第二相强化作用得以显现,此时硅单晶的硬度不随间隙氧浓度的降低而减小,反而有较为显著的提高. 关键词:单晶硅; 氧沉淀; 维氏硬度; [全文内容正在添加中] ......
The Splittings of p_± States in Infrared Spectra of Thermal Donors in Silicon朱悟新,王富咸摘 要:<正> p -type CZ silicon crystals annealed at 450℃ have been investigated by low temperature infraredspectroscopy with high resolusion. It has been shown that the 2p± and 3p± bands of neutral thermal donorsTD° are all split into two bands, which have not been......
Study on Growth and Spectra Properties of Nd∶GGG Crystal曾繁明,孙晶,张莹,刘景和摘 要:The laser crystal Nd∶GGG was grown by Cz method. The optimum processing parameter is that the pulling rate is 2~4 mm·h-1, the rotation rate is 20~40 r·min-1 and the cooling rate is 20 ℃. The absorption and fluorescence spectra of Nd∶GGG were measured. The main absorption peak of Nd......
of the melt flow in the Czochralski (CZ) crystal growth configuration, the three dimensional (3D) modeling, the simulation of melt flow under the magnetic field, the inverse modeling and the time......
CeO2基储氧材料的制备和表征(英文)李红梅1,2,兰丽1,刘达玉1,王卫1,薛慧玲1,漆文胜1,龚茂初2,陈耀强21. 成都大学2. 四川大学绿色化学与技术教育部重点实验室摘 要:用共沉淀法制备了4种CeO2基储氧材料,并用X射线衍射(XRD),Raman光谱,N2吸附-脱附(BET方法),H2程序升温还原(H2-TPR),氧脉冲技术,X射线光电子能谱(XPS)和扫描电子显微镜(SEM)表征了其物理化学性质.XRD结果表明,在CeO2和CeO2-Al2O3 (CA)中只能检测到宽的CeO2的特征峰,而CeO2-ZrO2 (CZ)和CeO2-ZrO2-Al2O3 (CZA)中检测到了Ce0.75Zr0.25O2相,所有的CeO2基储氧材料中都形成了均匀的固溶体.XPS结果表明,三价铈和四价铈共存于CZ......
properties and leaching characteristics of volcanic weathered crust elution-deposited rare earth ore from Chongzuo(CZ), Guangxi province were investigated. It was found that the CZ rare earth ore......
;WC晶粒长大激活能随Com值的增加先上升后下降,在Com为5.2%左右时达到最高值.这是由于碳含量较低时,随着碳含量的增加,WC晶粒表面生成的晶粒长大抑制剂(Crx,Vy)Cz碳化物增加,但随着碳含量的继续增加,(Crx,Vy)Cz的生成量已达到极值,而产生液相的温度进一步下降,液相量急剧增加,WC晶粒长大激活能又开始下降.关键词:超细晶硬质合金;WC-6Co;总碳;Com;WC晶粒......
(WMC长焰煤,LL3焦煤,LL4焦煤,CZ无烟煤与SH无烟煤)的碳结构特征及其演化进行了研究.结果表明:(1)变质程度是影响煤中碳结构演化的最重要因素.随着煤变质程度的增加,煤中芳碳率增大,芳香核缩聚程度增加,芳香结构单元排列趋于有序.(2)变质环境对煤的碳结构演化具有重要影响.高温低压环境下,WMC煤中芳香结构单元发生超前演化,形成一系列堆垛高度大延展度小的芳香结构体系;脂肪类物质中,一方面脂肪侧链发生快速热解,形成较多的环甲基,另一方面煤中已有的脂肪环发生热解断裂,形成新的脂肪链,导致支链化程度增加.(3)中等变质程度的LL4与LL3煤中发生了显著的脂环化作用,导致其季碳含量明显增高,支链化程度降低.(4)随着变质程度增加,CZ与SH煤样中,脂肪环发生断裂,形成新的脂肪链致使支链化程度增加,成为高变质程度煤中形成更大芳香体系的前奏.关键词:变质程度;芳香碳;脂肪碳;演化;......
"><正>Large-sized (-2 inch, 50.8 mm)γ-LiAlO2 single crystal has been grown by conventional Czochralski (Cz) method, but the crystal has a milky, dendriform center. The samples taken from... of transparent and milky parts were increased to 55.2 and 80.9 arcsec, respectively. By combining Cz technique with VTE technique, large-sized and high qualityγ-LiAlO2 crystal can be obtained.