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Entanglement in the supermolecular dimer [Mn4]2
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作者 许长谭 陈刚 +1 位作者 贺明明 梁九卿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2828-2834,共7页
This paper investigates the entanglement in the supermolecular dimer [Mn4]2 consisting of a pair of single molecular magnets with antiferromagnetic exchange-coupllng J. The conventional yon Neumann entropy as a functi... This paper investigates the entanglement in the supermolecular dimer [Mn4]2 consisting of a pair of single molecular magnets with antiferromagnetic exchange-coupllng J. The conventional yon Neumann entropy as a function of the exchange-coupling is calculated explicitly for all eigenstates with the quantum number range from M = M1 + M2 = -9 to 0. It is shown that the yon Neumann entropy is not a monotonic function of the coupling strength. However, it is significant that the entropy of entanglement has the maximum values and the minimum values for most eigenstates, which is extremely useful in the quantum computing. It also presents the time-evolution of entanglement from various initial states. The results are useful in the design of devices based on the entanglement of two molecular magnets. 展开更多
关键词 ENTANGLEMENT supermolecular dimer [Mn4]2 EXCHANGE-COUPLING time-evolution of entanglement
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高分子间相互作用的特点及意义 被引量:14
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作者 朱平平 杨海洋 何平笙 《高分子通报》 CAS CSCD 2002年第5期73-78,共6页
高分子间的相互作用与小分子间的相互作用有着显著的区别 ,导致高分子物质在凝聚态结构和诸多性能上明显地有别于小分子物质。本文就如下七个方面 :特别强的高分子间相互作用、特殊的高聚物溶解过程、马克三角形原理、特征温度、特有的... 高分子间的相互作用与小分子间的相互作用有着显著的区别 ,导致高分子物质在凝聚态结构和诸多性能上明显地有别于小分子物质。本文就如下七个方面 :特别强的高分子间相互作用、特殊的高聚物溶解过程、马克三角形原理、特征温度、特有的单链凝聚态。 展开更多
关键词 分子间相互作用 高分子 单链凝聚态 溶胀 凝聚缠结 超分子体系 结构
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原子力显微镜观察脂胞囊形貌结构及稳定性 被引量:11
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作者 孙润广 张静 《原子与分子物理学报》 CAS CSCD 北大核心 2003年第1期85-88,共4页
用原子力显微镜 (AFM)观察了液晶态脂胞囊形貌结构和稳定性。实验结果显示 ,对于 1,2 二油酸甘油 3 磷脂酰乙醇胺 (DOPE)超分子聚集体 ,在扫描区域内 ,可观察到一些大小不同球形颗粒 ;对于 1,2 二油酸甘油 3 磷脂酸乙醇胺 (DOPE)和 1... 用原子力显微镜 (AFM)观察了液晶态脂胞囊形貌结构和稳定性。实验结果显示 ,对于 1,2 二油酸甘油 3 磷脂酰乙醇胺 (DOPE)超分子聚集体 ,在扫描区域内 ,可观察到一些大小不同球形颗粒 ;对于 1,2 二油酸甘油 3 磷脂酸乙醇胺 (DOPE)和 1,2 二油酸甘油 3 磷脂酰胆碱 (DOPC)混合的超分子聚集体 ,则不仅观察到类似脂胞囊的球形颗粒 ,而且也观察到了双层膜结构 ,其厚度约为 5~ 6nm。 展开更多
关键词 原子力显微镜 脂双层膜 超分子聚集体 稳定性 形貌结构 脂胞囊 液晶态 生物膜
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脂质体的液晶态结构和稳定性研究 被引量:7
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作者 张静 孙润广 《液晶与显示》 CAS CSCD 2003年第4期266-270,共5页
用原子力显微镜(AFM)观察了液晶态LB膜和脂质体形貌的结构和稳定性。实验结果表明,在扫描区域内,对于DOPE脂质体,可观察到一些由DOPE超分子聚集体形成的大小不同的球形颗粒;对于DOPE和DOPC混合脂质体,则不仅观察到类似脂质体的球形颗粒... 用原子力显微镜(AFM)观察了液晶态LB膜和脂质体形貌的结构和稳定性。实验结果表明,在扫描区域内,对于DOPE脂质体,可观察到一些由DOPE超分子聚集体形成的大小不同的球形颗粒;对于DOPE和DOPC混合脂质体,则不仅观察到类似脂质体的球形颗粒,而且也观察到了双层膜结构,其厚度约为5~6nm。随着NaCl浓度的增加,它们的双层膜更稳定。葡萄糖和蔗糖对脂双层膜结构有稳定作用。 展开更多
关键词 液晶态 稳定性 脂质体 原子力显微镜 超分子聚集体 双层膜结构
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三维超分子体系[Cu(C_5H_7NO_2)·H_2O]·H_2O配合物的合成、晶体结构及旋光活性 被引量:2
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作者 郭应臣 卓立宏 +1 位作者 段玉芳 黄群增 《应用化学》 CAS CSCD 北大核心 2007年第3期318-322,共5页
将醋酸铜、L-谷氨酸和无水醋酸钠按1∶2∶4摩尔比经室温固相反应,合成了一种新的配合物[Cu(C5H7NO2)·H2O]·H2O。通过元素分析、红外光谱、差热-热重及X射线单晶衍射测试技术对其结构进行了表征。差热-热重分析显示,该配合物含... 将醋酸铜、L-谷氨酸和无水醋酸钠按1∶2∶4摩尔比经室温固相反应,合成了一种新的配合物[Cu(C5H7NO2)·H2O]·H2O。通过元素分析、红外光谱、差热-热重及X射线单晶衍射测试技术对其结构进行了表征。差热-热重分析显示,该配合物含有1分子结晶水和1分子配位水。晶体结构解析表明,晶体属正交晶系,P2(1)2(1)2(1)空间群,晶胞参数为:a=0.7244(2)nm,b=1.0330(3)nm,c=1.1075(3)nm,Z=4,V=0.8288(4)nm3,Dc=1.961g/cm3,μ=2.635mm-1,F(000)=500,R1=0.0307,wR2=0.0696,GOF=1.012。该化合物由L-谷氨酸中C1羧基上氧原子、氨基氮原子、C5羧基上氧原子及1个水分子中氧原子与中心Cu(Ⅱ)离子配位,形成五配位的畸变四方锥构型。四方锥之间通过羧基氧原子与结晶水或配位水形成分子间氢键,这种氢键及弱相互作用相互连接构成了L-谷氨基酸铜配合物的三维网状超分子体系。旋光活性测定表明,配合物为左旋体,比旋光度为[α]1D5=-38.5°(水),其旋光方向与配体相反,这是由于氨基氮及羧基氧参与配位形成五元环,改变了手性碳原子周围环境,从而使旋光方向改变。 展开更多
关键词 三维超分子体系 L-谷氨酸 铜(Ⅱ)配合物 晶体结构 旋光活性
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氮苄叉苯胺-银纳米超分子体系的紫外光谱研究 被引量:3
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作者 曹朝暾 程时茂 曹晨忠 《化学研究与应用》 CAS CSCD 北大核心 2019年第9期1635-1642,共8页
合成了38个不含OH,NH2和SH基团的4,4’-二取代氮苄叉苯胺衍生物(p-XBAY-p)以及银纳米粒子,分别测定了p-XBAY-p、银纳米粒子(AgNPs)以及(p-XBAY-p)-AgNPs超分子体系的紫外吸收光谱,研究了取代基效应对该超分子体系紫外光谱的影响。结果表... 合成了38个不含OH,NH2和SH基团的4,4’-二取代氮苄叉苯胺衍生物(p-XBAY-p)以及银纳米粒子,分别测定了p-XBAY-p、银纳米粒子(AgNPs)以及(p-XBAY-p)-AgNPs超分子体系的紫外吸收光谱,研究了取代基效应对该超分子体系紫外光谱的影响。结果表明:化合物的紫外吸收波长会随着AgNPs的加入而发生不同程度的偏移,并存在偏移极限,其偏移程度与取代基X和Y有关;通过纳米粒度电位仪(Nano ZS90,Malvern)测定,超分子体系中银纳米粒子体积变大;用Hammett参数σ,激发态取代基参数σcc^ex对超分子体系紫外吸收光谱的偏移值ΔνWSL(波数,cm-1)进行定量相关,得到一个三参数方程。所得方程表明,本文(p-XBAY-p)-AgNPs超分子体系紫外光谱的变化规律与含羟基二芳基席夫碱-银纳米超分子体系紫外光谱的变化规律有较大差异。 展开更多
关键词 氮苄叉苯胺 银纳米粒子 超分子体系 紫外光谱 取代基效应
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利用超分子体系模拟生物体G蛋白耦联受体型信号转导过程 被引量:1
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作者 刘宝全 王剑锋 +1 位作者 石太德 范圣第 《大连民族学院学报》 CAS 2011年第3期248-252,共5页
以生物体G蛋白耦联受体型信号转导过程为模拟原型,利用自组装方法构建了具有分子间信号转导能力的超分子体系。带正电荷的肽脂质分子与人工受体共同形成脂质体,乳酸脱氢酶(LDH)(效应器)通过静电作用吸附到脂质体上,乳酸脱氢酶的竞争性... 以生物体G蛋白耦联受体型信号转导过程为模拟原型,利用自组装方法构建了具有分子间信号转导能力的超分子体系。带正电荷的肽脂质分子与人工受体共同形成脂质体,乳酸脱氢酶(LDH)(效应器)通过静电作用吸附到脂质体上,乳酸脱氢酶的竞争性抑制剂(Cu2+)抑制LDH活性(相对酶活性为11.6%),进而共同组成了一个酶活性处于关闭状态的超分子系统。向超分子体系中加入信号分子——磷酸吡哆醛(PLP)后,PLP通过静电作用吸附到带正电荷的脂质体表面,并与人工受体形成希夫碱;希夫碱与LDH竞争铜离子,解除铜离子对LDH活性的抑制,恢复LDH的催化活性,使相对酶活性达到83.0%。实验结果表明,超分子体系完成了从信号分子到效应器(酶)活性变化的信号转导过程,可以利用超分子体系构建调控酶催化活性的超分子器件。 展开更多
关键词 超分子体系 信号转导 乳酸脱氢酶 纳米器件
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重质油胶体聚集结构的耗散粒子动力学模拟 被引量:13
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作者 张胜飞 孙丽丽 +2 位作者 徐俊波 周涵 温浩 《物理化学学报》 SCIE CAS CSCD 北大核心 2010年第1期57-65,共9页
重质油是以沥青质为胶核分散于饱和油分中形成的极其复杂的胶体体系.本文采用耗散粒子动力学(DPD)方法研究重质油的胶体结构及其影响因素.根据重质油各组分的分子结构特征,构建了描述重质油组分的粗粒化模型化合物.模拟结果表明,本文构... 重质油是以沥青质为胶核分散于饱和油分中形成的极其复杂的胶体体系.本文采用耗散粒子动力学(DPD)方法研究重质油的胶体结构及其影响因素.根据重质油各组分的分子结构特征,构建了描述重质油组分的粗粒化模型化合物.模拟结果表明,本文构建的粗粒化模型能很好地反映重质油的胶体聚集结构.沥青质分子结构对胶体聚集结构有序性有显著影响,较高稠合程度的芳香环结构将使胶束结构有较高的有序性,烷基侧链则表现出分散作用.重质油中的胶质具有胶溶作用,胶质与沥青质的浓度比存在一个极限,当小于这个极限时,重质油将出现聚沉. 展开更多
关键词 重质油 胶体 多分散体系 自缔合 超分子结构 聚集结构 耗散粒子动力学
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酸性铬蓝K的电化学行为及其与β-环糊精超分子体系的研究
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作者 王欢 刘建波 顾玲 《染料与染色》 CAS 2009年第3期20-24,共5页
本文研究了酸性铬蓝K的极谱分析法。结果表明,在pH=10.0的NH3-NH4Cl底液中,酸性铬蓝K产生一峰形好、稳定、灵敏的还原峰,其峰电位约为-0.56V(vsSCE),峰电流及二阶导数极谱峰高随酸性铬蓝K浓度变化的线性范围在8.0×10-8mol/L~3.0&#... 本文研究了酸性铬蓝K的极谱分析法。结果表明,在pH=10.0的NH3-NH4Cl底液中,酸性铬蓝K产生一峰形好、稳定、灵敏的还原峰,其峰电位约为-0.56V(vsSCE),峰电流及二阶导数极谱峰高随酸性铬蓝K浓度变化的线性范围在8.0×10-8mol/L~3.0×10-5mol/L(r=0.996~0.9999),检测限为2.0×10-8mol/L,精密度RSD=0.646%(n=10),标准回收率在99.4%~103.4%之间,平均回收率为100.97%,可望用于酸性铬蓝K的定量分析。此外,本文还研究了β-环糊精对酸性铬蓝K电化学行为的影响和超分子体系;利用等摩尔系列法测定了酸性铬蓝K与β-环糊精形成的包结物的包结比为1∶1,用电流法测定其包结常数为33.4L/moL;并且测定了酸性铬蓝K的还原峰电流和扫描速度、客体浓度及pH值的关系,峰电位与pH值的关系,初步讨论电极反应机理。 展开更多
关键词 酸性铬蓝K Β-环糊精 极谱分析法 超分子
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杯芳烃内相中3-环丁烯砜的分解反应研究 被引量:1
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作者 王亦秋 杨作银 +1 位作者 张敬畅 曹维良 《北京化工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第5期34-38,共5页
采用分子动态模拟及量子化学方法对杯芳烃内相中3-环丁烯砜的取向及分解为二氧化硫和丁二烯的反应进行了研究。结果表明,3-环丁烯砜在杯芳烃分子反应器中发生分解反应的活化能比在自由状态下反应的活化能略高,这与3-环丁烯砜在杯芳烃中... 采用分子动态模拟及量子化学方法对杯芳烃内相中3-环丁烯砜的取向及分解为二氧化硫和丁二烯的反应进行了研究。结果表明,3-环丁烯砜在杯芳烃分子反应器中发生分解反应的活化能比在自由状态下反应的活化能略高,这与3-环丁烯砜在杯芳烃中的表观分解温度提高的实验现象吻合。分析分子反应器与小分子的相互作用能以及分子反应器的变形能随反应进程的变化趋势,发现活化能的变化主要源自分子反应器与小分子的相互排斥作用。 展开更多
关键词 杯芳烃 3-环丁烯砜 超分子体系 量子化学计算
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STUDY ON POLYPYRROLE-VISCOSE CONDUCTING FIBER
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作者 江建明 张玉梅 李光 《Journal of China Textile University(English Edition)》 EI CAS 1996年第1期1-8,共8页
The conductivity of Polypyrrole-viscose conducting fiber prepared with author’s method can be shown up to as high as 2.106x10<sup>-2</sup> S/cm. The main factors influencing the conductivity are the conce... The conductivity of Polypyrrole-viscose conducting fiber prepared with author’s method can be shown up to as high as 2.106x10<sup>-2</sup> S/cm. The main factors influencing the conductivity are the concentration of FeCl<sub>3</sub> used as dopant and initiator, the treatment time of viscose fiber as base material in FeCl<sub>3</sub> solution, temperature and polymerization time. It is found that the orientation and crystallization degree of viscose fiber keep constant before and after conducting treatment and the mechanical properties of conducting fiber is the same as that of base material. In addition, the distribution of polypyrrole in viscose fiber, and its effect on the conductivity were investigated in details by TEM. 展开更多
关键词 VISCOSE CONDUCTING fiber mechanical properties supermolecular structures POLYPYRROLE CONDUCTIVITY BASE POLYMER
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THE INFLUENCE OF DRAWING CONDITIONS OF PET POY ON STRUCTURE AND PROPERTY OF THE FIBER
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作者 穆淑华 《Journal of China Textile University(English Edition)》 EI CAS 1990年第3期33-40,共8页
Drawing tests upon PET POY have been made by using dynamic thermal stress analyser,which show that the dynamic thermal stress of fiber is readily affected by drawing conditions. Aseries of samples have been obtained u... Drawing tests upon PET POY have been made by using dynamic thermal stress analyser,which show that the dynamic thermal stress of fiber is readily affected by drawing conditions. Aseries of samples have been obtained under different drawing velocities, drawing temperatures anddraw ratios. The variations of structural factors of fiber such as the orientation, crystallinity,crystallite size and the thermal shrinkage have been measured. It is proved through experimentsthat the thermal shrinkage(Y) of the drawn fiber of PET POY is influenced by the orientation (rep-resented by sonic velocity x<sub>1</sub>) and crystallinity (x<sub>2</sub>) of the fiber. The quantitative relationship is es-tablished using the binary regression method: Y=10.2246+2.2030x<sub>1</sub>-26.2670x<sub>2</sub> The mechanical properties such as tenacity, elongation, yield stress, initial modulus and the te-nacity at 10% elongation, etc. have also been measured. The relations between the tenacity at 10%elongation (D) and drawing velocity(V), draw ratio (DR), drawing temperature (T), and sonic ve-locity and crystallinity have been obtained using a method of mathematical statistics: D=4.594-0.009 6V , D=-8.937+7.170DR, D=2.866+0.00629T, D=-7.34+2.866x<sub>1</sub>+6.314x<sub>2</sub> These equations fit well with data from the experiments. This work will be benefical to the control of quality of products and the development of newproducts. 展开更多
关键词 POLYESTER supermolecular structure DRAWING THERMAL SHRINKAGE dynamic THERMAL stress TENACITY at 10% ELONGATION
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A Review of Studies of Polymeric Membranes by Positron Annihilation Lifetime Spectroscopy
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作者 Htwe Htwe +3 位作者 Yin 阴泽杰 马卫涛 朱大鸣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第5期3062-3064,共3页
A review is presented of studies of polymeric membranes by applying positron annihilation lifetime spectroscopy (PALS). PALS has been used to study subnanometer-sized holes, to determine their size distribution and ... A review is presented of studies of polymeric membranes by applying positron annihilation lifetime spectroscopy (PALS). PALS has been used to study subnanometer-sized holes, to determine their size distribution and free-volume fractions, and to probe molecular-sized vacancies in glassy polymers. At present, PALS is believed to be a highly effective physical method for the examination of polymeric membranes. 展开更多
关键词 polymeric membrane applying positron annihilation lifetime spectroscopy(PALS) nuclear track DESALINATION PERMEABILITY reverse osmosis supermolecular struc-ture
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SYNTHESIS OF LADDERLIKE POLYHYDROXYPROPYLSILSESQUIOXANE
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作者 Huai-zhong Pan Chun-qing Liu +6 位作者 Zhong Jin Ming Cao Jian-hua Luo Ping Xie Rong-ben Zhang Yu-hui Lin Neal Tai-sheng Chung Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Institute of Materials Research and Engineering, Singapore 117602, Singapore 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期453-457,共5页
Ladderlike polyhydroxypropylsilsesquioxane (HO-T) was synthesized by alcoholysis of ladderlike poly(3-propionyloxy-propyl)silsesquioxane. The HO-T was characterized by GPC, IR, NMR, DSC, TGA and X-ray diffraction meth... Ladderlike polyhydroxypropylsilsesquioxane (HO-T) was synthesized by alcoholysis of ladderlike poly(3-propionyloxy-propyl)silsesquioxane. The HO-T was characterized by GPC, IR, NMR, DSC, TGA and X-ray diffraction methods. Through hydrogen-bonding interaction, ladderlike polymer (HO-T) can form a supramolecular complex with somewhat regular structure. 展开更多
关键词 ladderlike polyhydroxypropylsilsesquioxane hydrogen-bond interaction supermolecular complex
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RELATION BETWEEN STRUCTURE OF PP DRAWN FILAMENT AND TEXTURING EFFECT
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作者 仲蕾兰 戚慰先 +1 位作者 江建明 曹正燕 《Journal of China Textile University(English Edition)》 EI CAS 1991年第1期48-54,共7页
The relationship between the structure of PP drawn filament and the crimp elasticity of tex-tured yarn is investigated.It is found that orientation,crystallinity,and especially,crystalline formof drawn filament are re... The relationship between the structure of PP drawn filament and the crimp elasticity of tex-tured yarn is investigated.It is found that orientation,crystallinity,and especially,crystalline formof drawn filament are related to crimp property of textured yarn.Lower crystallinity,moderateorientation and unstable para-crystalline structure are necessary for increasing crimp elasticity.Inaddition,the filament structure and properties before and after texturing are compared. 展开更多
关键词 polypropylene FIBRE FIBRE STRUCTURE TEXTURED YARN orientation supermolecular STRUCTURE false twist TEXTURING CRYSTALLINITY crystalline form crimp elasticity
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Studies of Ce(Ⅲ)-ALC-F Interacting with Herring Sperm DNA by Electrochemical, Fluorimetric and UV-spectrophotometric Method
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作者 GuangHanLU WeiLIU ChuanYinLIU LiPingJIANG FengSONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期443-446,共4页
Ce(Ⅲ)-ALC-F complex can react with hsDNA to form an electrochemically non-active supermolecular complex Ce(Ⅲ)-ALC-F-DNA in the buffer solution of (CH2)6N4(pH=4.9), which results in the decrease of the peak current o... Ce(Ⅲ)-ALC-F complex can react with hsDNA to form an electrochemically non-active supermolecular complex Ce(Ⅲ)-ALC-F-DNA in the buffer solution of (CH2)6N4(pH=4.9), which results in the decrease of the peak current of Ce(Ⅲ)-ALC-F. This method can be applied to determine DNA concentration. In addition, by using fluorimetric and UV-spectrophotometric methods with studies of denatured DNA and the effect of NaCl solution , it is also found that the binding mode is intercalation. 展开更多
关键词 Ce(Ⅲ)-ALC-F electrochemically non-active supermolecular complex herring sperm DNA(hsDNA) FLUORIMETRY UV-SPECTROPHOTOMETRY intercalation.
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Studies on the Structures and Properties of Latent-crimp Copolyester Fibers
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作者 顾书英 李光 顾利霞 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期1-4,共4页
The internal causes of latent-crimp were analyzed bystudying the supermolecular structures of the standardpolyester fibers(PET),copolyester fibers(IPET)andtheir side-by-side composite fibers(PET/IPET)inthis paper.It i... The internal causes of latent-crimp were analyzed bystudying the supermolecular structures of the standardpolyester fibers(PET),copolyester fibers(IPET)andtheir side-by-side composite fibers(PET/IPET)inthis paper.It is concluded that IPET and PET/IPEThave better latent-crimp ability because of their asym-metric supermolecular structures.At the same time,they have good dyeability and mechanical properties.Soit is a simple and low cost process to manufacture latent-crimp continuous fibers by melt-spinning of the co-polyester IPET. 展开更多
关键词 COPOLYESTER LATENT - CRIMP supermolecular structure.
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SHG from centrosymmetric supermolecular crystal
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作者 郭文生 刘祁涛 +4 位作者 邵宗书 郭放 周广勇 魏春生 王东 《Science China Chemistry》 SCIE EI CAS 2002年第3期267-274,共8页
Supermolecular crystal composed of p-nitrophenol, hexamethylenetetramine, phosphoric acid and water was obtained by supermolecular assembly. The crystal has a centrosymmetric structure with space group P21/c. The rela... Supermolecular crystal composed of p-nitrophenol, hexamethylenetetramine, phosphoric acid and water was obtained by supermolecular assembly. The crystal has a centrosymmetric structure with space group P21/c. The relative intensity and integral value of green frequency doubling of light from the crystal powder compared with that from KDP powder measured by pico-second Nd:YAG laser are 757.3 (KDP: 183.4) and 1771.7 (KDP: 423.98), respectively. In supermolecular crystal, due to the arrangement of centrosymmetric p-nitrophenol molecules in the inorganic-organic host framework formed by hexamethylenetetramine, phosphoric acid and water, the distances between the p-nitrophenol molecules with centrosymmetry are changed (N1A-O1A: 0.8158 nm, N1B’-O1B: 1.4450 nm, N1A-N1A’: 0.5837 nm, N1B’-N1B: 0.6898 nm), and the interaction between the dipoles becomes weak, which is easy for the ground state to turn into the excited state charge separated form, and generate the stable asymmetrical distribution of π-electron cloud density of quinonal structure, thus exhibiting SHG effect. 展开更多
关键词 supermolecular CRYSTAL SHG EFFECT centrosymmetry p-nitrophenol.
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二芳基硝酮-银纳米超分子体系的紫外光谱 被引量:3
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作者 冯娇娇 曹晨忠 《湖南科技大学学报(自然科学版)》 CAS 北大核心 2020年第2期95-99,共5页
为了探索二芳基硝酮(XPNY)在银纳米粒子(AgNPs)作用下的紫外吸收性能,本文合成了23个XPNY化合物,并制备了AgNPs溶液,在无水乙醇中,测定了XPNY和XPNY-AgNPs溶液的紫外吸收光谱,与文献报导的氮苄叉苯胺-银纳米(XBAY-AgNPs)和N-(苯亚乙基)... 为了探索二芳基硝酮(XPNY)在银纳米粒子(AgNPs)作用下的紫外吸收性能,本文合成了23个XPNY化合物,并制备了AgNPs溶液,在无水乙醇中,测定了XPNY和XPNY-AgNPs溶液的紫外吸收光谱,与文献报导的氮苄叉苯胺-银纳米(XBAY-AgNPs)和N-(苯亚乙基)苯胺-银纳米(XPEAY-AgNPs)体系紫外吸收光谱的变化规律进行比较.结果表明:(1)XPNY-AgNPs与XBAY-AgNPs和XPEAY-AgNPs体系相比,紫外吸收光谱的变化规律不同.(2)XPNY-AgNPs紫外吸收的ΔνWSL主要受取代基X和Y的激发态取代基常数,取代基X的场/诱导效应常数,Y的共轭效应常数以及基团X和Y之间的交叉作用项等的共同影响.(3)由于XBAY,XPEAY和XPNY这3类化合物分子中的桥键不同,当它们与银纳米粒子发生作用,紫外吸收光谱受到取代基效应的影响差别较大,XBAY-AgNPs和XPEAY-AgNPs的极限波长λ’max,lim相对于XBAY和XPEAY的λ’max既有红移也有蓝移;而XPNY-AgNPs的λ’max,lim相对于XPNY的λ’max只发生红移.该结果对理解XBAY,XPEAY和XPNY这3类化合物在银纳米作用下的紫外吸收光谱有理论意义,也可为相应化合物-银纳米的紫外吸收光谱的检测应用提供参考. 展开更多
关键词 二芳基硝酮 银纳米 超分子体系 紫外吸收光谱 取代基效应
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Effective sugar-derived organic gelator for three different types of lubricant oils to improve tribological performance 被引量:2
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作者 Ruochong ZHANG Xuqing LIU +2 位作者 Zhiguang GUO Meirong CAI Lei SHI 《Friction》 SCIE CSCD 2020年第6期1025-1038,共14页
In this study,the gelling ability and lubrication performance of N-octadecyl-D-gluconamides(NOG)in liquid paraffin(LP),pentaerythritol oleate(PE-OA),and polyethylene glycol(PEG)oils were systemically investigated.The ... In this study,the gelling ability and lubrication performance of N-octadecyl-D-gluconamides(NOG)in liquid paraffin(LP),pentaerythritol oleate(PE-OA),and polyethylene glycol(PEG)oils were systemically investigated.The NOG,which could gelate the investigated oils,was successfully synthesized by a one-step method.The prepared gel lubricants were completely thermoreversible and exhibited improved thermal stability,according to the thermogravimetry analysis(TGA)reports.Rheological tests confirmed that the NOG gelator could effectively regulate the rheological behavior of the base oils.Tribological evaluation suggested that NOG,as an additive in the three types of base oils,could remarkably reduce the friction and wear in steel contacts.A plausible mechanism for the improved performances was proposed based on the mechanical strength of the gels and the formation of the boundary-lubricating film on the worn surface.The results indicated that NOG is a potential gelator for preparing gel lubricants with excellent tribological properties and environment-friendly characteristics. 展开更多
关键词 gel lubricant supermolecular assembly rheological property tribological performance lubricating mechanism
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