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淀粉改性官能团化作为金属离子的吸附剂用于废水处理已有报道,但吸附效果不理想,应用范围受限制。本文将玉米淀粉接枝甲基丙烯酸缩水甘油酯共聚物(Cs-g-PGMA)与甘氨酸反应,得到Cs-g-PGMA-Gly作为吸附剂,可以去除水中的Cd~(2 )、Cr~(3 )等有害元素,而且在适当的pH条件下还可富集分离Au~(3 )、Pd~(2 )。 相似文献
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Cyril Párkányi William C. Herndon 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):231-232
Abstract Several coordination complexes of cyclobutadiene (I) have been prepared (e.g., cyclobutadiene iron tricarbonyl [1]) and cyclooctatetraene (II) is a well-known compound (for a potentially planar form of cyclooctatetraene, see [2]). Although butalene [3] (III) has not been synthesized so far, octalene (IV) has been obtained by Vogel and co-workers [4,5]. Recently we have carried out a theoretical study of the physical and chemical properties of butalene (III) and octalene (IV), and of the various annelated butalenes and octalenes [6,7] using the HMO and SCF-MO (PPP) quantum-chemical methods as well as the structure-resonance theory and graph theoretical methods. Numerous theoretical data are available in the literature on cyclobutadiene (I) and cyclooctatetraene (II). 相似文献
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噻吩甲酰基吡唑啉酮缩乙二胺配合物的合成、表征及生物活性 总被引:8,自引:0,他引:8
A new ligand N,N′-bis[(1-phenyl-3-methyl-5-oxo-4-pyrazolinyl)-2-thenoylmethylidyne]ethyl-enediimine (HPMTHP)2en and its five complexes have been sythesized. These complexes have the general formula [M(PMTHP)2en], where M=Cu(Ⅱ), Ni(Ⅱ) 相似文献
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烷基和烷氧基取代聚噻吩的合成、表征与光电性能 总被引:13,自引:0,他引:13
Fe(Ⅲ )氧化催化法合成了 4种聚噻吩衍生物 ,3 十二烷基聚噻吩 (Pat12 ) ,3 辛氧基聚噻吩 (Paot8) ,3,4 二 (十二烷基 )聚噻吩 (Pat12 12 )和 3 (十二烷基 )噻吩 3 (辛氧基 )噻吩共聚物 (CoPt12 o8) .发现这些衍生物易溶于多种常用有机溶剂 .用GPC法测定了各聚合物分子量 ,用1 H NMR法表征了各聚合物化学结构 .对比研究了这些聚合物紫外 可见吸收性能 ,光致发光性能和能隙 .对其电致发光性能进行测定的结果 ,得到了Pat12 ,Pat12 12和Paot8的电致发光光谱 .发射峰分别为 6 70nm ,5 6 0nm和 6 4 0nm .发光颜色分别为红色 ,黄色和红橙色 .聚合物的光电性能与主链电子结构有密切关系 .探讨了取代基种类和数量对聚合物能带结构 ,光电性能的影响 . 相似文献
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Rlnaldo Cubeddu Francesco Ghetti Francesco Lenci Roberta Ramponi Paola Taroni 《Photochemistry and photobiology》1990,52(3):567-573
Abstract— A computer-controlled apparatus for time-resolved laser fluorescence spectroscopy has been used to measure fluorescence lifetimes, time-integrated and time-gated spectra of crude extracts of blepharismin, the photoreceptor pigment of the ciliated photoresponsive protozoan Blepharisma japonicum , in ethanol, aqueous solutions and detergent micelles. The effect of hydroxyl concentration has been investigated in both alcohol and water solutions. A short-living (0.2-0.4 ns) molecular species, emitting at 600 nm, is predominant in aqueous solutions at pH < 11.7, whereas in pure ethanol solutions an intermediate-living species (about 1 ns), still fluorescing at 600 nm, prevails. Upon increasing OFF concentration, a third, long-living (about4–6 ns) molecular species, emitting at 660 nm, is formed in all the examined media. This species has been tentatively identified as the negatively charged form of the photoreceptor pigment, whereas the short-living and the intermediate-living fluorescence emissions have been attributed respectively to the phenolic and the quinonic neutral forms of blepharismin. The phenolic form in its ground state is suggested to be the molecular species from which proton release occurs. 相似文献
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本文用自旋捕捉技术、柱色谱与ESR波谱相结合的方法, 研究了Ph_3M(M=N, P, As, Sb, Bi)光解过程的活泼自由基。从自旋捕捉剂亚硝基特丁烷(t-BuNO)、苯亚甲基叔丁基氮氧化合物(PBN)或2,3,4,6-四甲基亚硝基苯(ND)与活泼自由基形成的自旋加合物的ESR波谱的超精细结构, 确证这些化合物光解过程中有Ph·自由基存在。从而可推断它们的光解初级过程包括Ph_3M的均裂, 即Ph_3M→Ph_2M·+Ph·。此外,因Ph—M键能的大小顺序为
Pb—P>Ph—As>Pb—Sb>Ph—Bi
所以Ph_2M·(M=As, Sb, Bi)的分解比Ph_2P·容易, 实验中只检查出Ph_2P·, 则正是所预期的。 相似文献
Pb—P>Ph—As>Pb—Sb>Ph—Bi
所以Ph_2M·(M=As, Sb, Bi)的分解比Ph_2P·容易, 实验中只检查出Ph_2P·, 则正是所预期的。 相似文献
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根据Franck-Condon原理,用PPP-SC(β,γ)-CI方法在IBM-PC微机上,对苯、萘、蒽的衍生物的荧光性质以及基态和第一激发单重态在键级、偶极矩、π电子总能量上的差异进行了研究。发现最大荧光波数V~(F.L.)与荧光辐射能△F~(V.L.)、荧光量子产率φ与基态、第一激发单重态间的π电子能量差(E_g~π—E_e~π)存在着以下的关系:上述F.L.表示荧光,g表示基态,e表示激发态。由此得出的理论计算值与实验值有着良好的一致性。 相似文献
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从二苯胺 4 重氮盐(DS)和3 甲氧基二苯胺 4 重氮盐(MDS)以及重氮树脂(DR)和硝基重氮树脂(NDR)与亚硫酸钠反应,在水溶液中制备了相应的二苯胺 4 偶氮磺酸盐DSS和MDSS(简称偶氮磺酸盐)及相应的重氮树脂的偶氮磺酸盐DRS和NDRS(简称偶氮磺酸盐树脂).对它们在水溶液和固相膜中的光、热反应进行了研究.结果表明偶氮磺酸盐与偶氮磺酸盐树脂有很好的感光性能,而热稳定性比相应的重氮盐和重氮树脂好很多,其中二苯胺上有硝基取代的偶氮磺酸盐树脂具有突出的热稳定性,其水溶液在70℃加热6h,其固相膜在100℃加热11天几乎观察不到分解.对偶氮磺酸盐及偶氮磺酸盐树脂的光、热分解机理作了初步分析. 相似文献
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本文将前文~[1,2]建议的直接计算交替烃HOMO(最高占据分子轨道)、LUMO(最低未占分子轨道)能量的方法推广到非交替烃。在HMO近似内, 对非交替烃分子的邻接矩阵联合应用逆迭代和Rayleigh商, 只需迭代一次就能得到该分子HOMO(或LUMO)能量的足够精确的结果。文中提出了计算的格式, 说明了选择初始变分函数的原则。用这种方法, 计算了30个分子的前线轨道~[3]能量, 平均误差为0.002β。本文提出了计算LOMO(最低占据分子轨道)能量的拓扑公式, 它同时适用于交替烃和非交替烃, 其计算精度要优于文献中曾经报道过的结果。用例子说明了方法的应用。 相似文献
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在硅凝胶中培养了标题配合物的单晶,确定了它的组成,并进行了热谱、可见光谱、红外光谱及其他多项物理性质的测试和表征,其结果与单晶X射线衍射分析的结果一致。晶体学数据:分子式[K(18-冠-6)(H_2O)][K(18-冠-6)][Cr(H_2O)(NCS)_5]·H_2O,空间群C_(2h)~5—P2_1/n,a=8.592(5),b=22.976(10),c=24.372(4)A,13=96.57(4)~0,Z=4。结构用直接法解出,全矩阵最小二乘方修正,R=0.046。结果表明,铬(Ⅲ)由五个异硫氯酸根离子和一水分子配位形成一畸变八面体形的配合阴离子。一个钾离子由一个冠醚和另一水分子配位;另一钾离子由另一冠醚和一配位于铬(Ⅲ)的硫氯酸根的硫原子配位,即该N(3)-C(3)-S(3)桥连在Cr和K(2)之间;两钾离子均是7配位。第三个水分子通过氢键与阴离子的配位水分子和两个冠醚环上的醚氧原子相连。 相似文献
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N,N-二甲基对甲基苯胺(DMT)是一个典型的电子给体,可以和多种电子受体形成称之为CCT(Contact Charge Transfer)的络合物。在光照条件下,这种络合物可以生成离子自由基,从而引起一系列反应。 相似文献
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R. S. H. Liu Erik Krogh Xiao-Yuan Li Dennis Mead L. U. Colmenares J. R. Thiel Jeannette Ellis Darren Wong A. E. Asato 《Photochemistry and photobiology》1993,58(5):701-705
Prompted by the near infrared-absorbing properties of some of the azulenic bacteriorhodopsin (bR) analogs, we have analyzed their absorption characteristics along with 11 new related ring-fused analogs and the corresponding Schiff bases (SB) and protonated Schiff bases (PSB). The following three factors are believed to contribute to the total red shift of each of the pigment analogs (αRS): perturbation of the basic chromophore (SB shift, ΔSB), protonation of the SB (PSB shift, PSBS) and protein perturbation (the opsin shift, OS). For each factor, effects of structural modifications were examined. For the red-shifted pigments, percent OS has been suggested as an alternate way of measuring protein perturbation. Computer-simulated chromophores provided evidence against any explanation involving altered shapes of the binding pocket as a major cause for absorption differences. Implications of the current bR results on preparation of further red-shifted bR and possible application to visual pigment analogs are discussed. 相似文献