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世界光盘生产及需求动向(Ⅲ) 总被引:1,自引:1,他引:0
(续上期)3.5DVD系列1996年末,DVD作为新的存储格式登台亮相。当初,以民用DVD-Video流行起来,以后便是PC用的DVD-ROM大出风头。由于DVD介质容量大,非常适合高画质影像记录和大容量数据存储,所以最早的产品便是DVD-Video和DVD-ROM。DVD-Video首先在美国取得巨大成功,需求量暴涨。接着,在日本上也呈现出高速增长的势头。预计世界性的DVD产业将在2000年进入成长期。DVD与其他存储格式相比,应用的历史还短。除DVD-Video和DVD-ROM外,属于DVD… 相似文献
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mLLDPE及mLLDPE/LDPE共混物薄膜性能研究 总被引:3,自引:1,他引:2
研讨了茂金属线型低密度聚乙烯(mLLDPE)薄膜和mLLDPE与低密度聚乙烯(LDPE)共混物薄膜的物理性能和光学性能,并与传统的LLDPE薄膜和LLDPE/LDPE共混物薄膜进行了比较,表明mLLDPE薄膜和mLLDPE/LDPE共混物薄膜的性能优于传统的LLDPE薄膜和LLDP/LDPE共混物薄膜,指出在mLLDPE中混合10%LDPE,对薄膜性能影响不大。 相似文献
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新型双功能硫化促进剂MD和DD通过鉴定新型双功能硫化促进剂MD和DD于1994年12月16日在镇江市通过了江苏省省级鉴定。促进剂MD和DD是促进剂M和DM分别与具有防老化功能的树脂及活化剂的复合产品,在促进硫化功能上分别和促进剂M和DM相当,同时兼有... 相似文献
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我厂DD型预分解窑设计产量为2000t/d,回转窑规格为Ф4m x60m,窑尾采用从日本引进的双系列五级悬浮预热器和DD型分解炉技术。该线于1992年底建成投产,至今已投产运行近8年。DD炉是预分解系统中的关键设备,为了更好地深入领会DD炉的设计意图、工作机理及系统匹配,1995年对DD炉系统进行了反求研究,得出了该系统有关的技术参数和技术特点,给生产提供了很好的指导作用。笔者结合反求研究的基本结论,并结合该线百年的生产实践,就DD型分解炉作一分析。1DD型分解炉的特点 DD型分解炉是在以高效、环… 相似文献
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双环戊二烯酚型树脂的合成及其结构表征 总被引:2,自引:0,他引:2
在80 ̄140℃下DCPD与苯酚(或烷基酚)经催化反应合成DCPD酚型树脂。研究了反应温度,反应时间,催化剂用量、DCPD与酚的配比等条件对合成DCPD酚树脂的影响。经红外光谱及核磁共振光谱表征了DCPD酚树脂的化学结构。 相似文献
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以交联单体双环戊二烯二甲双缩水甘油酯(DGDCA)的特征峰(1712cm^-1)和环氧氯丙烷均聚物(PECH)的特征峰(750cm^-1)为定量计算的基准峰,测定不同质量比的DGDCA与PECH混合物IR谱图。混合物组成与光密度比值(D1712/D750)关系的回归方程为:(D1712/D750=0.0209+6.64WDGDCWECH),进而建立了通过D1712/D750求取共聚物中DGDCA结 相似文献
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双环戊二烯酚型环氧树脂的固化反应研究 总被引:3,自引:0,他引:3
研究了DCPD酚环氧树脂与酸酐及胺类固化剂的固化反应活性。通过DSC热分析方法表征了DCPD酚环氧树脂与甲基六氢苯酐(MeHHPA)及4,4′-二氨基二苯甲烷(DDM)的固化反应过程,测定了反应热焓,并分析了固化温度、时间及固化剂结构等对DCPD酚环氧树脂凝胶时间及固化度的影响,探讨了温度、时间对DCPD酚环氧树脂固化反应活性的影响。 相似文献
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In addition to the etherification of cellulose by N-methylol and N-alkoxymethyl agents that results in crosslinking, hydrolysis reactions that liberate formaldehyde can also occur. The hydrolysis of representative reactants was followed under acidic and basic conditions, through deetherification and demethylolation, to formaldehyde release. Functional groups were identified by the use of nuclear magnetic resonance spectroscopy. Results were used to interpret the behavior of finishes from these agents on cotton fabrics, particularly with respect to the special influence of alcohols. 相似文献
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Observations and conclusions drawn from a model N-methylol reactant system have been used to study formaldehyde release from cotton fabric treated with N,N′-dimethylol-4,5-dihydroxy-ethyleneurea (DMDHEU). Reagent residues produced by DMDHEU in the presence of sodium bisulfate or zinc nitrate were found to be more complex than those formed from the N-methylolpyrrolidone (NMP) reactant system, and the exact nature of some of the residues from DMDHEU could not be established. Zinc nitrate produces higher fixation of DMDHEU on cotton as compared to sodium bisulfate and also reduces formaldehyde release. As is the case with the NMP system, the lower amount of formaldehyde release with zinc nitrate catalyst is believed to be at least partially due to the formation of a complex between the N-methylol reactant, DMDHEU, and zinc nitrate. The C? OCell bonds in both finishes resist acid-catalyzed cleavage but cleavage of the N? C bonds in N-methylol groups (to release formadehyde) in the presence of acid is greater for the DMDHEU system than for the NMP system. Results with the DMDHEU and NMP systems are similar, but because of the complex nature of the products formed in the DMDHEU system it is very difficult to correlated formaldehyde release with specific chemical structures of residues or reactants. 相似文献
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通过试验研究了脲醛缓释肥、脲醛缓释肥加尿素及尿素等6个养分投入量相同的处理对橡胶树胶水产量的影响.试验结果表明,施用脲醛缓释肥,提高了橡胶树胶水产量,以肥料中掺混60%脲醛缓释肥和40%普通尿素一次性施用效果最好,既降低了施用脲醛缓释肥的成本,又节省了劳动力. 相似文献
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The effect of subsequent heating on formaldehyde release from DMDHEU-finished fabric has been examined. Formaldehyde release was higher at higher heating temperatures, but fabrics cured at higher temperatures showed less released formaldehyde. Adding urea reduced formaldehyde release. 相似文献
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对环境测试舱进行了25 d跟踪测试,包括甲醛本底浓度测试、甲醛释放、甲醛浓度衰减、通风换气和舱内表面吸附甲醛重新释放各阶段,考察环境测试舱内甲醛吸附消耗量及重新释放规律,探索有效控制措施. 结果表明,环境测试舱中甲醛浓度C的变化符合对数函数C=Alnt+B [舱内甲醛释放时A>0, B>0,舱内甲醛衰减时A<0, B>0,t为时间(h)],其中A与舱内吸附甲醛释放后再次达到相对平衡的浓度密切相关;采用抽气式通风换气系统有利于舱内残余甲醛的消减,关闭此通风换气系统后,舱内甲醛浓度初期浓度快速递增,在相对较低的甲醛浓度(0.3203 mg/m3)时再次达到相对平衡;环境测试舱内吸附程度与基体表面吸附比q和撞到基体表面的吸附质的物质的量U有关. 相似文献
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细木工板中甲醛释放特征及规律 总被引:2,自引:0,他引:2
采用环境测试舱模拟室内环境,测量细木工板中甲醛的释放浓度,考察细木工板结构、温度、相对湿度和空气交换率对甲醛释放的影响,分析细木工板中甲醛气体扩散机理,并建立了灰色预测模型对细木工板中甲醛释放峰值后的过程进行模拟. 结果表明,细木工板中甲醛散发通道主要为端面,端面的甲醛释放量是平面的3倍;细木工板中甲醛气体扩散过程分为3个阶段(初始快速释放、稳定释放和长期缓速释放);空气交换率对细木工板中甲醛释放率影响不大;相对湿度和温度升高,细木工板中甲醛释放率也增大;预测模型的预测数据与实验数据吻合较好,平均相对误差率仅为3.717%,适合进行长期预测. 相似文献
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A model N-methylol reactant system based on pyrrolidone derivatives has been used to study the chemical factors that control formaldehyde release. Fabric samples of known composition were prepared from chemically pure reactants and formaldehyde release was determined by the AATCC Sealed Jar Test. This work provides support for prior suggestions and a more direct approach for understanding unexpected results from tests on post-and precure fabrics. In addition, new findings demonstrate that the N-methylol reactant, its byproducts, and pure zinc nitrate are capable of reducing the level of formaldehyde release. 相似文献