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1.
用从头算法在6-31G基组下,对π型氢键体系C2H2.HCl,C2H4.HCl和H2C=CHC≡CH.HCl及其组份分子的稳定构型进行了全优化。对于C2H2.HCl和C2H4.HCl分别得到了一种稳定的π型氢络合物,对于H2C=CHC≡CH.HCl得到了顺式和反式两种可能的π型氢键络合物,此外,用MP2法对上述四种络合物作了相关能校正,得到了氢键键能分别为13.217,14.446,15.562和  相似文献   

2.
测定了293.2~323.2K间的7个温度下电池GE|H2O(1-w)+En(OH)2(w)+HCl(m)|AgCl-Ag的电动势,由此求得了上述7个温度下,m=0.0020,0.0050,0.0100,0.0500,0.1000mol/kg的HCl在0~90%乙二醇—水二元混合溶剂中的平均活度系数γ±与Pitzer参数;HCl自水向各组成En(OH)2—H2O混合溶剂中的标准迁移自由能,标准迁移熵和标准迁移焓.最后从分子间相互作用的角度对HCl在该混合溶剂中的热力学行为给予了理论解释.  相似文献   

3.
N2O2型Sc hiff碱配体和锰(Ⅲ)配合物的合成与光谱表征   总被引:1,自引:1,他引:0  
报道了8 个水杨醛及邻香草醛与二胺缩合生成的Schiff碱与锰(Ⅲ)的配合物:[Mn(salpn)Cl],[Mn(salipn)Cl],[Mn(vanipn)Cl],[Mn(salen)(H2O)]ClO4,[Mn(vanen)(H2O)2]2(ClO4)2(H2O)2,[Mn(vanipn)(H2O)2]2(ClO4)2(H2O)2,[Mn(salen)(NCS)],[{Mn(osalphen)(NCS)}{Mn(salphen)(NCS)(DMF)}](其中sal为水杨醛,van 为邻香草醛,en 为乙二胺,pn 为1,3丙二胺,ipn 为1,2丙二胺,ophen 为邻苯二胺).对所有的配合物进行了元素分析.对配合物中的ν(C= N),δ1(CH3,CH2),δ2(CH3,CH2),ν(C- N),ν(C= C),ν(Mn- O)以及DMF和ClO-4 、NCS- 的振动吸收进行了归属.紫外光谱测试表明,配合物中存在着芳环的π→π,金属到配体的CT电荷转移跃迁,C= N的π→π以及d→π跃迁.磁距测定表明,配合物的中心离子为d4 锰(Ⅲ)高自旋的电子结构.  相似文献   

4.
用二次量子化方法讨论了HCl分子在激光场中的多光子激发,这包括对HCl分子伸缩振动能级的计算,跃迁概率随外场频率的变化及随时间的变化(取光场强度10-8W/cm2).  相似文献   

5.
研究了四苯基卟啉钆配合物在CH2Cl2,DMSO及混合溶剂DMSOCH2Cl2,DMSOH2O中的可见光谱.测定了在CH2Cl2溶剂中配合物与DMSO反应的平衡常数及配比  相似文献   

6.
运用休克尔分子轨道(HMO)理论对紫红质中的色基-视黄醛骨架异构化现象进行了讨论挖计算结果表明:紫红质中视黄醛骨架共轭体系π→π*跃迁的最大吸收峰λmax=563nm,这与紫红质的λmax=498nm相近,但列接近受压紫红质的实验结果λmax=534nm;且视黄醛骨架结构共轭体系中C11-C12之间激发态的π键级为1.5860。明显小于基态π键级1.7469值,故当紫红质吸收光能进入激发态之后,1  相似文献   

7.
平面型的侧基配位双核锆分子氮络合物{[1-prPCH_2SiMe_2)_2N]ZrCl}_2(μ- ̄2η:η ̄2-N_2)的电子结构、成键图象以及锆碎片络合物与分子氮轨道相互作用是通过量子化学SCC-DV-Xa计算得到的,结果表明这类前过渡金属原子的d轨道和分子氮1π_g轨道之间有较强的d-π作用,以致对分子氮有显著的活化作用.  相似文献   

8.
研究了氯化碘的B^3Π0^+态(振动能级V'=12、16)的发散荧光光谱和碰撞电子淬灭。借助激光诱地荧光的方法,以氩离子激光器的502.3nm和514.5nm谱线做为泵浦源,并使用稳态近似处理得到了这两个态与气态ICl、H2O、CH2Cl2、CH3OH、C2H5OH、CH3NH2、C2H5NH2、CCl4和苯分子碰撞的电子淬灭速率常数和碰撞截面。我们探讨了分子间的相互作用,并且对比了ICl和IF的  相似文献   

9.
该文合成了苯甲酰三氯乙酰丙酮(简称L)和三苯基氧化磷(Tppo)、联吡啶(Bipy)、邻菲罗林(Phen)、四甲基氢氧化铵(NMe4OH)与Nd、Ho、Er的三合型和四合型配合物共十二种。常温下测定配合物在CHCl3溶剂中的紫外吸收光谱,发现吸收峰都有不同程度的紫移。配合物在固态下的f—f超灵敏跃迁吸收峰红移。  相似文献   

10.
研究了四苯基卟啉钆配合物在CH2Cl2,DMSO及混合溶剂DMSO-H2Cl2,DMSO-H2O中的可见光谱。测定了在CH2Cl2溶剂中配合物与DMSO反应的平衡常数及配比。  相似文献   

11.
ABS/PC合金的剖析与表征   总被引:2,自引:0,他引:2  
剖析和表征了两种国产ABS的相组分和结构、藉差示扫描量热(DSC)法研究了不同腈含量的苯乙烯丙烯腈的共聚物(SAN)与聚碳酸酯(PC)的相容性。通过Fox方程计算出PC溶在SAN中的百分含量的以及SAN溶在PC中的百分含量。用红外光谱法剖析了两种ABS的助剂,发现含有酯类助剂的ABS合导致了PC分解,不宜与PC共混。  相似文献   

12.
单片机与PC键盘接口部件的连接方法   总被引:1,自引:1,他引:0  
带有PC键盘接口的部件有PC键盘、条码器等设备,这些设备可与计算机直接连接使用,单片机也可以与这些部件连接,其通讯协议在格式上与RS232相同,但需要时钟同步.本文介绍用8031与PC键盘连接的方法.  相似文献   

13.
构造了一种扩展的双曲同余码(EHC),用该码作为时间扩频伪随机序列和以素数码(PC)作为波长跳频伪随机序列,形成了一种新的二维光正交码EHC/PC.与EQC/PC相比,两者的码字数相同,互相关性能相当,但前者扩频系数和码重较小,可以提高用户的数据速率并降低对光编/解码器的要求.模拟计算表明,当同时使用的用户数较少时,EQC/PC的误码率比EHC/PC略低;当同时使用的用户数中等或较多时,两者的误码率性能相当.因此,EHC/PC比EQC/PC更适合于同时使用的用户数中等或较多的光码分多址(OCDMA)系统.  相似文献   

14.
Chromatic sensitivity of ganglion cells in the peripheral primate retina   总被引:3,自引:0,他引:3  
Martin PR  Lee BB  White AJ  Solomon SG  Rüttiger L 《Nature》2001,410(6831):933-936
Visual abilities change over the visual field. For example, our ability to detect movement is better in peripheral vision than in foveal vision, but colour discrimination is markedly worse. The deterioration of colour vision has been attributed to reduced colour specificity in cells of the midget, parvocellular (PC) visual pathway in the peripheral retina. We have measured the colour specificity (red-green chromatic modulation sensitivity) of PC cells at eccentricities between 20 and 50 degrees in the macaque retina. Here we show that most peripheral PC cells have red-green modulation sensitivity close to that of foveal PC cells. This result is incompatible with the view that PC pathway cells in peripheral retina make indiscriminate connections ('random wiring') with retinal circuits devoted to different spectral types of cone photoreceptors. We show that selective cone connections can be maintained by dendritic field anisotropy, consistent with the morphology of PC cell dendritic fields in peripheral retina. Our results also imply that postretinal mechanisms contribute to the psychophysically demonstrated deterioration of colour discrimination in the peripheral visual field.  相似文献   

15.
在对上海交通大学住校本科生参与游戏情况开展调查的基础上,文章分析了电脑游戏对学生各方面素质的影响,并全面了解电脑游戏本身以及它和学生的关系.研究结果表明,电脑游戏对学生的影响有利有弊,不同游戏影响也不同.要让电脑和网络在人才培养中真正起到推动作用,校方必须结合实际情况,从各方面着手,特别是在文化和意识形态层面上改善学生的游戏观,从而营造良好的学习环境,培养适应时代要求的优秀人才.  相似文献   

16.
Neuronal growth inhibitory factor (GIF),named Metaliothioneins-Ⅲ (MT-Ⅲ), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochromocytoma PC12 by the MTT (Thiazolyl blue) reduction assay. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for detecting neuronal growth inhibitory activity of GIF. Recombinant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhibiting PC12 may be that PC12 have some properties of cholinergic neuron. It must play an important role in discovering the mechanism of GIF's neuronal growth inhibitory activity.``  相似文献   

17.
对再生塑料颗粒表面对改善混凝土的力学性能进行了研究,将2组成分相同表面粗糙度不同的再生塑料颗粒添加到混凝土中,等体积取代部分细骨料,然后对再生塑料改性混凝土进行立方体抗压强度、劈裂抗拉强度、轴心抗压强度及抗折强度试验.试验结果表明,掺入表面粗糙的再生塑料颗粒的混凝土的力学性能优于掺入表面光滑的再生塑料颗粒的混凝土.  相似文献   

18.
Neuronal growth inhibitory factor (GIF), named Metallothioneins-Ⅲ (MT-Ⅲ), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochromocytoma PC12 by the MTT (Thiazolyl blue) reduction assay. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for detecting neuronal growth inhibitory activity of GIF. Recombinant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhibiting PC12 may be that PC12 have some properties of cholinergic neuron. It must play an important role in discovering the mechanism of GIF’s neuronal growth inhibitory activity.  相似文献   

19.
Differentiation of PC12 phaeochromocytoma cells induced by v-src oncogene   总被引:2,自引:0,他引:2  
S Alemà  P Casalbore  E Agostini  F Tatò 《Nature》1985,316(6028):557-559
PC12 rat phaeochromocytoma cells are a model system that can be used to study both neuronal differentiation and the mechanism of action of nerve growth factor (NGF). PC12 cells respond to NGF protein by shifting from a chromaffin-cell-like phenotype to a neurite-bearing sympathetic neurone-like phenotype. Here we present data on the effect of infection of PC12 cells with retroviruses carrying the src oncogene of Rous sarcoma virus. Previous studies have demonstrated that the expression of src severely affects the synthesis and accumulation of differentiated cell products in a variety of cell types. We show that in the PC12 cell system, expression of v-src appears to have an inductive effect on differentiation that resembles the action of a 'physiological' growth factor.  相似文献   

20.
为了在汽车锁生产中实现大规模钥匙加工,设计并实现了一种基于工业PC和PLC技术的全自动专用数控系统。该系统是一个分布式的全自动专用数控系统.采用工业PC为主控系统,利用PLC控制机械手系统、检测开关信号、通过DIO接口与主控PC进行通讯。采用面向对象的软件设计方法,运用有限自动机模型,研制了系统控制软件、产品数据管理软件。该系统性能稳定可靠,已在汽车锁专业生产企业得到应用。  相似文献   

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