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981.
982.
离子色谱荧光检测法测定废水中痕量2-氨基联苯和4-氨基联苯 总被引:2,自引:0,他引:2
采用离子色谱荧光检测法测定废水中的2-氨基联苯(2-ADP)和4-氨基联苯(4-ADP),流动相为1.0mL/min的0.06mol/L NaCl,0.08mol/L HCl,40%(V/V)ACN,分离柱为Dinoex OmniPac PCX-500,该法具有良好的重现性和线性关系,2-ADP和4-ADP的回收率分别为98.5%-101.4%和102.2%-104.0%,检测限分别为0.006mg/L和0.10mg/L。 相似文献
983.
A density functional and ab initio theory investigation on M@B9 and M@B10 molecular wheels containing planar nona- and deca-coordinate heavy group 11, 12 and 13 metals (M=Ag, Au, Cd, Hg, In, Ti)
has been performed. These unusual clusters all prove to be true minima on the potential energy surfaces of the systems and
σ+π double aromatic in nature. The first two vertical one-electron detachment energies of M@B10− (M=Ag, Au) anions and first two ionization potentials of M@B9 (M=Ag, Au) and M@B10 (M=Cd, Hg) neutrals were calculated to aid future experiments. The cluster complexes designed in this work may expend the
domain of planar hyper-coordinate elements to include heavy group 11, 12, and 13 metals and serve as interesting candidates
to be targeted in experiments.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.
Supported by the National Natural Science Foundation of China (Grant No. 20873117) 相似文献
984.
设计了一台3000A液态下阴极电解槽,阴极为轧制钨板设置在槽底部,电解过程中阴极表面形成一层金属液而充当液态阴极作用,继续析出的金属流入坩埚中,阳极为方块状石墨块,由导杆悬挂于可升降的水平导电母线上,阴极处于阳极投影下方,阴阳极之间水平平行布置.在此设计的电解槽上进行金属钕的电解试验,电解槽稳定运行,电解槽电压与传统上插阴阳极式电解槽相比,槽电压大幅降低至6V以内,电流效率达到80%以上,本文还考察了该电解槽的电压分布情况、电流电压曲线、电解槽的热场分布情况. 相似文献
985.
Shaomin Ji Wanhua Wu Wenting Wu Huimin Guo Qi Yang Quan Wang Xin Zhang Yubo Wu Jianzhang Zhao 《Frontiers of Chemistry in China》2010,5(2):193-199
Polypyridyl ruthenium (Ru) complexes 1–3 were prepared. Their photophysical properties were investigated by UV-Vis absorption
and luminescence emission spectra. The luminescent lifetimes of these Ruthenium complex were prolonged by more than 5 folds
(τ = 2.50 μs for complex 3) when compared with the parent Ru complex 1 (τ = 0.45 μs). We propose that the extended luminescent
lifetime of complex 3 is due to the equilibrium between 3MLCT state and the pyrene localized 3π-π* triplet state (3IL). The luminescent O2-sensing property of the complexes in solution and the IMPEK-C polymer film were studied, and the O2 sensing was quantified with the two-site model. The oxygen-sensing property of the Ru complexes can be improved by 104-fold
with extension of the luminescent lifetimes. For example, the quenching constant K
SV was improved from 0.0023 Torr−1 of 1 to 0.2393 Torr−1 for 3. Our results demonstrated a versatile approach for the preparation of Ru (II) polypyridine complexes with extended
luminescent lifetimes as functional materials, for example, for luminescent oxygen-sensing applications. 相似文献
986.
987.
988.
Chang Peng Yuxue Liu Xiaojia Guo Wujun Liu Qing Li Zongbao K. Zhao 《Tetrahedron letters》2018,59(42):3810-3815
Selective carboxylation of substituted phenols is realized in the presence of bicarbonate under ambient pressure by engineered Escherichia coli whole-cells expressing various hydroxybenzoate decarboxylases, leading to their corresponding ortho-hydroxybenzoates. This process may be further developed as an efficient route to upgrade lignin-derived phenolic compounds as valuable building blocks. 相似文献
989.
990.
Isonitrile group has been identified in many natural products.Due to the broad reactivity of N≡C triple bond,these natural products have valuable pharmaceutical potentials.This review summarizes the current biosynthetic pathways and the corresponding enzymes that are responsible for isonitrile-containing natural product generation.Based on the strategies utilized,two fundamentally distinctive approaches are discussed.In addition,recent progress in elucidating isonitrile group formation mechanisms is also presented. 相似文献