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噁嗪750激光染料分子在醇类溶剂中超快动力学研究(英文) 被引量:1
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作者 周立川 刘建勇 +2 位作者 石英 赵广久 韩克利 《原子与分子物理学报》 CAS CSCD 北大核心 2007年第2期431-434,共4页
利用飞秒时间分辨荧光亏蚀光谱技术,研究了噁嗪750激光染料分子在典型的醇类溶剂中超快动力学过程.实验发现两个超快动力学过程:飞秒量级的快速弛豫过程和皮秒量级的慢速弛豫过程.快速弛豫过程来源于分子内振动能量再分配(IVR)和溶剂分... 利用飞秒时间分辨荧光亏蚀光谱技术,研究了噁嗪750激光染料分子在典型的醇类溶剂中超快动力学过程.实验发现两个超快动力学过程:飞秒量级的快速弛豫过程和皮秒量级的慢速弛豫过程.快速弛豫过程来源于分子内振动能量再分配(IVR)和溶剂分子超快惯性弛豫动力学过程,而慢速弛豫过程对应于溶剂化的扩散分子弛豫动力学过程.实验结果表明慢速弛豫过程的时间常数随醇溶剂分子间氢键键能的增强而增大. 展开更多
关键词 分子反应动力学 分子内振动能量再分配 溶剂化 飞秒时间分辨荧光亏蚀光谱 噁嗪750激光染 料分子
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柴油加氢装置扩能改造及分子筛料和清洁柴油试生产
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作者 卫建军 姜来 《石化技术与应用》 CAS 2011年第4期340-345,共6页
为扩大产能并实现分子筛料和清洁柴油生产,中国石油化工股份有限公司金陵分公司对140万t/a柴油加氢装置进行了技术改造。将催化剂更换为FHUDS-2深度加氢脱硫催化剂;新增1套分馏系统。改造后,分子筛料产率可达15%以上。在改造后的装置上... 为扩大产能并实现分子筛料和清洁柴油生产,中国石油化工股份有限公司金陵分公司对140万t/a柴油加氢装置进行了技术改造。将催化剂更换为FHUDS-2深度加氢脱硫催化剂;新增1套分馏系统。改造后,分子筛料产率可达15%以上。在改造后的装置上可同时生产分子筛料和硫质量分数小于50×10-6的清洁柴油,但反应器入口温度提高31℃,加工能力降低20 t/h。 展开更多
关键词 柴油 加氢装置 分子 清洁柴油
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燃煤电厂用新型高分子复合滤料性能的测试 被引量:1
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作者 王振华 沈恒根 薛婷婷 《产业用纺织品》 2013年第9期13-15,20,共4页
耐高温滤料的使用寿命和稳定性是影响袋式除尘器运行寿命的因素之一。对新型高分子复合滤料进行了基本性能的测试,并与目前燃煤电厂常用的玻纤滤料性能进行了对比试验。结果表明,新型复合滤料在耐高温、耐酸腐蚀和抗氧化性能方面均优于... 耐高温滤料的使用寿命和稳定性是影响袋式除尘器运行寿命的因素之一。对新型高分子复合滤料进行了基本性能的测试,并与目前燃煤电厂常用的玻纤滤料性能进行了对比试验。结果表明,新型复合滤料在耐高温、耐酸腐蚀和抗氧化性能方面均优于常用的玻纤滤料,适合在电厂烟气处理系统中应用。 展开更多
关键词 袋式除尘器 分子复合滤 玻纤滤 性能测试
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增产分子筛脱蜡装置原料工艺技术研究 被引量:2
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作者 孟宪筠 房立仲 王丽君 《当代化工》 CAS 2012年第4期356-359,共4页
抚顺石化公司有两套分子筛脱蜡装置,正常生产每年需求分子筛原料量75万t以上,在千万吨炼油项目未建成投产之前,直馏分子筛原料量不足60万t,分子筛原料缺口15万t以上,针对公司这一阶段两套分子筛装置运行原料不足的情况,利用公司加工大... 抚顺石化公司有两套分子筛脱蜡装置,正常生产每年需求分子筛原料量75万t以上,在千万吨炼油项目未建成投产之前,直馏分子筛原料量不足60万t,分子筛原料缺口15万t以上,针对公司这一阶段两套分子筛装置运行原料不足的情况,利用公司加工大庆、沈北原油的特点,以劣质柴油为原料通过中压加氢、高压加氢生产分子筛料的工艺对比实验,完成了劣质柴油通过加氢生产分子筛料的新工艺开发,实验在工业装置上得到应用。 展开更多
关键词 焦化柴油 加氢 分子 工业应用 效益
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基于RBF神经网络实现分子筛料干点的软测量建模
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作者 雷清卫 杜友福 《石油天然气学报》 CAS CSCD 北大核心 2003年第z1期156-157,共2页
以蒸馏装置常压塔的分子筛料干点为研究对象,基于现场采集数据及机理分析,确定辅导变量,用RBF神经元网络的方法建立数学模型实现对分子筛料干点的软测量。仿真结果表明模型精度达到了工艺要求。
关键词 软测量 神经元网络 干点 分子 蒸馏常压塔
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水溶性高分子纺织浆料的生物降解功能 被引量:4
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作者 洪耀 《纺织学报》 EI CAS CSCD 北大核心 2006年第6期104-106,110,共4页
通过对PVA、聚丙烯酸类浆料及浆料助剂生物降解性能的论述表明,原淀粉和聚丙烯酰胺这两类浆料的生物降解性能较好,而PVA是最难进行生物降解的,其它浆料对生态环境均有一定的污染。浆料助剂多数为表面活性剂,疏水的碳链越长越难生物降解... 通过对PVA、聚丙烯酸类浆料及浆料助剂生物降解性能的论述表明,原淀粉和聚丙烯酰胺这两类浆料的生物降解性能较好,而PVA是最难进行生物降解的,其它浆料对生态环境均有一定的污染。浆料助剂多数为表面活性剂,疏水的碳链越长越难生物降解,直链结构较支链结构的生化降解性相对较好。为解决PVA难以降解的问题,目前已开发出新一代的生物分解酶,可使PVA废液快速生物降解。 展开更多
关键词 分子 生物降解性 聚乙烯醇 聚丙烯酸 淀粉 变性淀粉 助剂
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水溶性高分子浆料的生物降解性能探讨 被引量:2
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作者 洪仲秋 《棉纺织技术》 CAS CSCD 北大核心 2003年第8期58-60,共3页
关键词 水溶性高分子 生物降解性能 废水生化处理 纺织废水 PVA 聚丙烯酸类
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大孔隙高分子聚合物混合料路用性能研究
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作者 巴学亮 许鹰 +1 位作者 何建彬 刘思铨 《山西建筑》 2018年第4期90-91,共2页
针对普通OGFC沥青混合料环保性差、服役寿命短的问题,尝试采用高分子聚合物胶粘剂代替沥青来制备大孔隙高分子聚合物混合料,并对两种混合料路用性能进行了对比,结果表明:大孔隙高分子聚合物混合料高低温性能优异;抗滑性能略低于OGFC沥... 针对普通OGFC沥青混合料环保性差、服役寿命短的问题,尝试采用高分子聚合物胶粘剂代替沥青来制备大孔隙高分子聚合物混合料,并对两种混合料路用性能进行了对比,结果表明:大孔隙高分子聚合物混合料高低温性能优异;抗滑性能略低于OGFC沥青混合料;对于大孔隙高分子聚合物混合料水稳定性,以浸水残留稳定度评价时,水稳定性较差,而以浸水飞散损失作为水稳定性评价指标不符合实际情况。 展开更多
关键词 大孔隙高分子聚合物混合 设计方法 路用性能
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焦化柴油生产分子筛料取得成功
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《河南化工》 CAS 2003年第7期50-51,共2页
关键词 焦化柴油 加氢 分子 中国石油抚顺石化分公司石油三厂
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SLS尼龙粉料成型工艺参数优化研究 被引量:1
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作者 李小城 《新乡学院学报》 2015年第3期50-53,共4页
用正交试验法对SLS尼龙粉料进行烧结实验,研究了SLS成型工艺对尼龙烧结件密度和强度的影响规律;结合材料性能对关键工艺参数做了进一步实验,确定了SLS尼龙粉料的最优工艺参数组合。其研究方法和结论对SLS高分子粉料成型工艺的确定有一... 用正交试验法对SLS尼龙粉料进行烧结实验,研究了SLS成型工艺对尼龙烧结件密度和强度的影响规律;结合材料性能对关键工艺参数做了进一步实验,确定了SLS尼龙粉料的最优工艺参数组合。其研究方法和结论对SLS高分子粉料成型工艺的确定有一定的参考价值。 展开更多
关键词 激光选区烧结 成型工艺参数 成型质量 SLS高分子
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水性油墨连接料的新进展 被引量:5
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作者 钟俊文 黄志虹 《涂料技术与文摘》 2003年第3期7-10,共4页
本文综述了水性油墨高分子连接料的发展动态。在环境保护压力的推动下,油墨逐渐向水性化方向发展,水性连接料一直存在着复溶性与耐水性的矛盾,为适应油墨分散介质的改变,连接料从与溶剂型同系物最接近的碱可溶乳液发展为复合型、反应型... 本文综述了水性油墨高分子连接料的发展动态。在环境保护压力的推动下,油墨逐渐向水性化方向发展,水性连接料一直存在着复溶性与耐水性的矛盾,为适应油墨分散介质的改变,连接料从与溶剂型同系物最接近的碱可溶乳液发展为复合型、反应型乳液。水性油墨连接料的许多性能比相应的溶剂型同系物有一定差距,水性高分子结构与性能的研究及存水性油墨中的应用是水性油墨发展的关键。 展开更多
关键词 水性油墨 分子连接 复溶性 耐水性 碱可溶乳液 复合乳液 反应型乳液
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Material Growth and Device Fabrication of GaAs Based 1.3μm GaInNAs Quantum Well Laser Diodes 被引量:1
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作者 牛智川 韩勤 +11 位作者 倪海桥 杨晓红 徐应强 杜云 张石勇 彭红玲 赵欢 吴东海 李树英 贺振宏 任正伟 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1860-1864,共5页
Material growth and device fabrication of the first 1.3μm quantum well (QW) edge emitting laser diodes in China are reported. Through the optimization of the molecular beam epitaxy (MBE) growth conditions and the... Material growth and device fabrication of the first 1.3μm quantum well (QW) edge emitting laser diodes in China are reported. Through the optimization of the molecular beam epitaxy (MBE) growth conditions and the tuning of the indium and nitrogen composition of the GalnNAs QWs, the emission wavelengths of the QWs can be tuned to 1.3μm. Ridge geometry waveguide laser diodes are fabricated. The lasing wavelength is 1.3μm under continuous current injection at room temperature with threshold current of 1kA/cm^2 for the laser diode structures with the cleaved facet mirrors. The output light power over 30mW is obtained. 展开更多
关键词 GaAs based materials GalnNAs quantum wells molecular beam epitaxy laser diodes
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The Effect of Silane Grafted Polypropylente on the Property of Different Filler/Polypropylene Composites
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作者 仇武林 罗运军 +1 位作者 罗善国 谭惠民 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期345-350,共6页
Aim To determine the effect of silane grafted polypropylene on the property of different filler/polypropylene composites. Methods Polypropylene (PP) composites filled with talc(Ta), baryta sulfate and calcium carbonat... Aim To determine the effect of silane grafted polypropylene on the property of different filler/polypropylene composites. Methods Polypropylene (PP) composites filled with talc(Ta), baryta sulfate and calcium carbonate coupled with silane grafted polypropylene (PP-g-Si) were made, their mechanical properties and thermal properties were investigated, respectively. Results As compared with the non-coupled composites, the mechanical properties of PP/Ta/PP-g-Si composites were improved to some extent, though the values of tensile modulus and the strain at peak were decreased. But for PP/BaSO4 and PP/CaCO3 composites, the values of their mechanical properties varied slightly or even decreased with increasing PP-g-Si content within the experimental component. Meanwhile, PP-g-Si also affected the melting and crystallization behavior of PP in the composites. Conclusion PP-g-Si offers compatibilization in PP/Ta composites, but offers no-compatibilization in PP/BaSO4 and PP/CaCO3 composites within the extent of the present range of PP-g-Si, which shows that PP-g-Si can be used as the macromolecular coupling agent of PP and Ta composite. 展开更多
关键词 silane grafted polypropylene composite macromolecular coupling agent POLYPROPYLENE
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BLOCK SPECTRUM CHARACTERISTICS AND FATIGUE CRACK RANDOM GROWTH 被引量:1
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作者 杨晓华 姚卫星 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期206-211,共6页
Two parameters,block spectrum intensity Seq and spectrum shape factor a,which describe the characteristics of the loading block spectrum are defined,and the relationship between the parameters and fatigue crack propag... Two parameters,block spectrum intensity Seq and spectrum shape factor a,which describe the characteristics of the loading block spectrum are defined,and the relationship between the parameters and fatigue crack propagation behaviours is investigated.It is shown that the spectrum intensity is an 'average drive force' of fatigue crack propagation,and the variance of fatigue crack size at a given fatigue life is closely related to the spectrum shape factor α. 展开更多
关键词 fatigue crack loading distribution random distribution material scatter block spectrum intensity shape factor
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用于丙烷催化燃烧的Pd_xPt_y-ZSM-5/Cordierite整体式催化剂 被引量:6
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作者 唐铨 郭杨龙 +3 位作者 詹望成 郭耘 王丽 王筠松 《化工学报》 EI CAS CSCD 北大核心 2019年第3期944-950,共7页
以ZSM-5分子筛、铝溶胶、硝酸钯、硝酸铂和水为原料制备分子筛浆料,采用真空抽提-一次涂覆法在堇青石蜂窝陶瓷载体表面制备出Pd_xPt_y-ZSM-5/Cordierite整体式催化剂,考察了Pd负载量、ZSM-5分子筛的硅铝比和Pd/Pt质量比对整体式催化剂... 以ZSM-5分子筛、铝溶胶、硝酸钯、硝酸铂和水为原料制备分子筛浆料,采用真空抽提-一次涂覆法在堇青石蜂窝陶瓷载体表面制备出Pd_xPt_y-ZSM-5/Cordierite整体式催化剂,考察了Pd负载量、ZSM-5分子筛的硅铝比和Pd/Pt质量比对整体式催化剂的丙烷催化燃烧性能的影响,并用超声波振荡、SEM、XRD、H_2-TPR和C_3H_8-TPD等手段对整体式催化剂进行了表征。当球磨时间为60 min,分子筛浆料固含量为38%时,整体式催化剂的涂层上载量可达到178 g·L^(-1),涂层脱落率低于0.5%。Pd_2Pt_3-ZSM-5/Cordierite整体式催化剂(贵金属总负载量为1.2g·L^(-1))对于丙烷的催化燃烧具有较好的催化活性(T_(50)=259℃,T_(90)=323℃)和稳定性,具有良好的工业应用前景,其中较低的ZSM-5分子筛硅铝比以及Pd和Pt之间的相互作用增加了对丙烷的吸附能力和表面活性氧物种的数量,从而提高了整体式催化剂的催化活性。 展开更多
关键词 丙烷 催化燃烧 真空抽提-一次涂覆法 整体式催化剂 分子筛浆 贵金属
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Ultrafiltration Enhanced with Activated Carbon Adsorption for Efficient Dye Removal from Aqueous Solution 被引量:7
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作者 董亚楠 苏延磊 +3 位作者 陈文娟 彭金明 张岩 姜忠义 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第5期863-869,共7页
In this study, orange G dye was efficiently removed from aqueous solution by ultraflltration (UF) membrane separation enhanced with activated carbon adsorption. The powdered activated carbon (PAC) was deposited on... In this study, orange G dye was efficiently removed from aqueous solution by ultraflltration (UF) membrane separation enhanced with activated carbon adsorption. The powdered activated carbon (PAC) was deposited onto the UF membrane surface, forming an intact filter cake. The enhanced UF process simultaneously exploited the high water permeation flux of porous membrane and the high adsorption ability of PAC toward dye molecules. The influencing factors on the dye removal were investigated. The results indicated that with sufficient PAC incorporation, the formation of intact PAC filtration cake led to nearly complete rejection for dye solution under opti-mized dye concentration and operation pressure, without large sacnticlng the permeation tlux ot the filtration process. Typically, the dye rejection ratio increased from 43.6% for single UF without adsorption to nearly 100% for the enhanced UF process, achieving long time continuous treatment with water permeation flux of 47 L·m^-2·h^-1. The present study demonstrated that adsorption enhanced UF may be a feasible method for the dye wastewater treatment. 展开更多
关键词 enhanced ultrafiltration powdered activated carbon filter cake ADSORPTION -dye removal
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Recent advances in the rational design of electrocatalysts towards the oxygen reduction reaction 被引量:5
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作者 Jianfei Kong Wenlong Cheng 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第6期951-969,共19页
The quest for low‐cost yet efficient non‐Pt electrocatalysts for the oxygen reduction reaction(ORR)has become one of the main focuses of research in the field of catalysis,which has implications for the development ... The quest for low‐cost yet efficient non‐Pt electrocatalysts for the oxygen reduction reaction(ORR)has become one of the main focuses of research in the field of catalysis,which has implications for the development of the next generation of greener fuel cells.Here,we comprehensively describe the'big picture'of recent advances made in the rational design of ORR electrocatalysts,including molecule‐based,metal‐oxide‐based,metal‐nanomaterial‐based and two‐dimensional electrocatalysts.Transition metals can fabricate molecular electrocatalysts with N4‐macrocycles such as porphyrin‐class compounds and the so‐formed M-N-C active centre plays a crucial role in determining the catalytic performances towards the ORR.Group‐IV and‐V Transition metal oxides represent another class of promising alternative of Pt‐based catalysts for the ORR which catalytic activity largely depends on the surface structure and the introduction of surface defects.Recent advances in synthesis of metallic nanoparticles(NPs)allow for precise control over particle sizes and shapes and the crystalline facets exposed to enhance the ORR performance of electrocatalysts.Two‐dimensional materials such as functionalized grapheme or MoS2are emerging as novel electrocatalysts for the ORR.This review covers various aspects towards the design of future ORR electrocatalysts,including the catalytic performance,stability,durability and cost.Some novel electrocatalysts even surpass commercial Pt/C systems,demonstrating their potential to be alternatives in industrial applications.Despite the encouraging progress,challenges,which are also described,remain to be overcome before the real‐world application of novel ORR electrocatalysts. 展开更多
关键词 Oxygen reduction reaction ELECTROCATALYST NANOMATERIAL Molecular electrocatalyt Two‐dimensional material
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Neuroendocrine and squamous colonic composite carcinoma:Case report with molecular analysis 被引量:3
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作者 Sabrina C Wentz Cindy Vnencak-Jones William V Chopp 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第42期4729-4733,共5页
Composite colorectal carcinomas are rare. There are amodest number of cases in the medical literature,with even fewer cases describing composite carcinoma with neuroendocrine and squamous components. There areto our k... Composite colorectal carcinomas are rare. There are amodest number of cases in the medical literature,with even fewer cases describing composite carcinoma with neuroendocrine and squamous components. There areto our knowledge no reports of composite carcinomamolecular alterations. We present a case of composite carcinoma of the splenic flexure in a 33 year-old Cau-casian male to investigate the presence and prognos-tic significance of molecular alterations in rare coloniccarcinoma subtypes. Formalin-fixed paraffin-embedded(FFPE) tissue was hematoxylin and eosin- and mucicar-mine-stained according to protocol,and immuno-stained with cytokeratin(CK) 7,CK20,CDX2,AE1/AE3,chromo-granin-A and synaptophysin. DNA was extracted from FFPE tissues and molecular analyses were performed according to lab-developed methods,followed by capil-lary electrophoresis. Hematoxylin and eosin staining showed admixed neuroendocrine and keratinized squamous cells. Positive nuclear CDX2 expression confirme dintestinal derivation. CK7 and CK20 were negative.Neuroendocrine cells stained positively for synaptophysin and AE1/AE3 and negatively for chromogranin and mucicarmine. Hepatic metastases showed a similar immunohistochemical profile. Molecular analysis revealeda G13D KRAS mutation. BRAF mutational testing wasnegative and microsatellite instability was not detected.The patient had rapid disease progression on chemotherapy and died 60 d after presentation. Although theG13D KRAS mutation normally predicts an intermed iateoutcome,the aggressive tumor behavior suggests other modifying factors in rare types of colonic carcinomas. 展开更多
关键词 Composite carcinoma NEUROENDOCRINE SQUAMOUS KRAS BRAF Microsatellite instability
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Application of Acid Dyestuffs with Different Molecule Structure in Combined Dyeing and Finishing of Cotton Fabric 被引量:1
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作者 董永春 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期50-54,共5页
Simultaneous dyeing and durable press finishing of cotton fabrics with acid dyes bearing the different molecule structure and durable press finishing agent (DP agent abbr.) based on modified DMDHEU were investigated b... Simultaneous dyeing and durable press finishing of cotton fabrics with acid dyes bearing the different molecule structure and durable press finishing agent (DP agent abbr.) based on modified DMDHEU were investigated by using the pad-dry-cure process. Some factors affecting the process, such as structure of acid dyes, DP agent, catalysts and curing temperature were discussed. The dyed and finished fabrics were evaluated with respect to color strength, fixation, crease recovery angle, breaking strength and fastness properties. The results indicate that structure of acid dyes has a striking effect on the color strength of dyed and finished cotton fabric. The color strength and dry crease recovery angle of dyed and finished cotton fabric increases, whereas breaking strength decreases with increasing concentration of DP agent. It is necessary for ammonium nitrate to serve as catalyst. It is found that relatively satisfactory properties of dyed and finished cotton fabric can be obtained with appropriate adjustment of treating conditions. 展开更多
关键词 acid dyes molecule structure single step dyeing durable press finishing
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Unusual Charge Transport and Spin Response of Doped Bilayer Triangular Antiferromagnets 被引量:3
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作者 LIANGying MATian-Xing FENGShi-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第6期749-756,共8页
Within the t-J model, the charge transport and spin response of the doped bilayer triangular antiferromagnetare studied by considering the bilayer interaction. Although the bilayer interaction leads to the band splitt... Within the t-J model, the charge transport and spin response of the doped bilayer triangular antiferromagnetare studied by considering the bilayer interaction. Although the bilayer interaction leads to the band splitting in theelectronic structure, the qualitative behaviors of the physical properties are the same as in the single layer case. Theconductivity spectrum shows the low-energy peak and unusual midinfrared band, the temperature-dependent resistivityis characterized by the nonlinearity metallic-like behavior in the higher temperature range and the deviation from themetallic-like behavior in the lower temperature range and the commensurate neutron scattering peak near the half-fillingis split into six incommensurate peaks in the underdoped regime, with the incommensurability increasing with the holeconcentration at lower dopings, and saturating at higher dopings. 展开更多
关键词 charge transport spin response t-J model
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