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71.
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远红外丙纶的性能研究 总被引:7,自引:2,他引:7
系统测试了采用共混纺丝法研制出的远红外丙纶及织物的物理机械性能、远红外发射性能、保温性能、耐洗涤性能和抗菌性能,并对用远红外丙纶加工的护腿的医疗保健作用进行了临床检测。进而讨论了远红外丙纶及织物的医疗保健作用机理。 相似文献
73.
GC/MS法测定电子电气塑料件中的限用含溴阻燃剂 总被引:3,自引:0,他引:3
建立了电子电气产品塑料部件中限用含溴阻燃剂多溴二苯醚(PBDE)和多溴联苯(PBB)的气相色谱/质谱(GC/MS)联用检测方法,成功应用于10种PBDE和8种PBB化合物的检测。样品经索氏提取器提取、固相硅胶净化小柱净化后,用GC/MS联用仪进行定性和定量特征离子分析。PBDE和PBB的线性分析范围为3.3~3 300 ng(绝对进样量),3种代表性化合物四溴联苯、十溴联苯和十溴二苯醚的加标回收率为76.4%~99.2%,十溴二苯醚的方法精密度为1.3%。结果表明,本方法应用于电子电气产品塑料部件中限用含溴阻燃剂的检测,操作简单,分析结果稳定,重现性好。 相似文献
74.
运用马尔科夫链模拟气化炉停留时间分布 总被引:4,自引:0,他引:4
将连续时间马尔科夫链与多级全混流串联模型结合建立停留时间分布数学模型。通过对气化炉流场的认识,将气化炉划分为几个区域状态,组成马尔科夫链状态转移图,用多级全混流模型表示该各个区域的混合程度。通过对两种气化炉停留时间分布的模拟和实验值进行对比,结果比较吻合,表明该模型模拟气化炉停留时间分布是可行的。 相似文献
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In this paper, a novel watermarking scheme for quantum images based on Hadamard transform is proposed. In the new scheme, a unitary transform controlled by a classical binary key is implemented on quantum image. Then, we utilize a dynamic vector, instead of a fixed parameter as in other previous schemes, to control the embedding process. The dynamic embedding vector is decided by both the carrier quantum image and the watermark image, which is only known by the authorized owner. The proposed scheme is analyzed from visual quality, computational complexity, and payload capacity. Analysis and results show that the proposed scheme has better visual quality under a higher embedding capacity and lower complexity compared with other schemes proposed recently. 相似文献
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Yun‐He Zhang Qin‐Hua Liu Ya‐Ming Niu Shu‐Ling Zhang Dong Wang Zhen‐Hua Jiang 《应用聚合物科学杂志》2005,97(4):1652-1658
A series of block copolymers composed of poly(ether ether ketone) (PEEK) and poly(ether ether ketone ketone) (PEEKK) components were prepared from their corresponding oligomers via a nucleophlilic aromatic substitution reaction. Various properties of the copolymers were investigated with differential scanning calorimetry (DSC) and a tensile testing machine. The results show that the copolymers exhibited no phase separation and that the relationship between the glass‐transition temperature (Tg) and the compositions of the copolymers approximately followed the formula Tg = Tg1X1 + Tg2X2, where Tg1 and Tg2 are the glass‐transition‐temperature values of PEEK and PEEKK, respectively, and X1 and X2 are the corresponding molar fractions of the PEEK and PEEKK segments in the copolymers, respectively. These copolymers showed good tensile properties. The crystallization kinetics of the copolymers were studied. The Avrami equation was used to describe the isothermal crystallization process. The nonisothermal crystallization was described by modified Avrami analysis by Jeziorny and by a combination of the Avrami and Ozawa equations. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1652–1658, 2005 相似文献
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The first use of nickel foam (NF) as electrocatalytic negative electrode in a polysulfide/bromine battery (PSB) is described. The performance of a PSB employing NF and polyacrylonitrile (PAN)-based carbon felt (CF) as negative and positive electrode materials, respectively, was evaluated by constant current charge-discharge tests in a single cell. Charge/discharge curves of the cell, positive and negative electrodes show that the rapid fall in cell voltage is due to the drop of positive potential caused by depletion of Br2 dissolved in the catholyte at the end of discharge. Cell voltage efficiency was limited by the relatively high internal ohmic resistance drop (iR drop). Polarization curves indicated that both NF and CF have excellent catalytic activity for the positive and negative redox reactions of PSB. The average energy efficiency of the single cell designed in this work could be as high as 77.2% at 40 mA cm−2 during 48 charge-discharge cycles. 相似文献