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151.
The liquid‐solid flotation separation behaviors of Cd2+ in ammonium sulfate‐potassium iodide‐cetylpyridine chloride‐water system and the conditions for the separation of Cd2+ from other metal ions were studied. The results showed that in the presence of 1.0 g (NH4)2SO4 and when the dosage of 0.1 M potassium iodide was 2.0 mL and 0.01 M cetylpyridine chloride (CPC) solution was 1.0 mL respectively, the formed water‐insoluble ternary association complex of KI‐CPC‐Cd floated above water phase and liquid‐solid phases were formed with clear interface. In this condition, Zn2+, Mn2+, Fe2+, Co2+, Ni2+ and Al3+ could not be floated and Cd2+ was floated quantitatively at pH 5.0. Therefore, the quantitative separation of Cd2+ from the above metal ions could be achieved. The quantitative flotation separation determination of Cd2+ in the sample of synthetic water and industrial waster water was performed, and the results agreed well with those by AAS method. The recoveries were 97.2%~102.4%, and the RSD was 1.8%. 相似文献
152.
Bingchu Tian Dr. Yanbo Shang Yi Tu Dr. Jun Hu Dr. Dong Han Qian Xu Prof. Shangfeng Yang Prof. Yifan Ye Dr. Honghe Ding Dr. Yu Li Prof. Junfa Zhu 《Chemphyschem》2023,24(20):e202300400
The interfacial electronic structure of perovskite layers and transport layers is critical for the performance and stability of perovskite solar cells (PSCs). The device performance of PSCs can generally be improved by adding a slight excess of lead iodide (PbI2) to the precursor solution. However, its underlying working mechanism is controversial. Here, we performed a comprehensive study of the electronic structures at the interface between CH3NH3PbI3 and C60 with and without the modification of PbI2 using in situ photoemission spectroscopy measurements. The correlation between the interfacial structures and the device performance was explored based on performance and stability tests. We found that there is an interfacial dipole reversal, and the downward band bending is larger at the CH3NH3PbI3/C60 interface with the modification of PbI2 as compared to that without PbI2. Therefore, PSCs with PbI2 modification exhibit faster charge carrier transport and slower carrier recombination. Nevertheless, the modification of PbI2 undermines the device stability due to aggravated iodide migration. Our findings provide a fundamental understanding of the CH3NH3PbI3/C60 interfacial structure from the perspective of the atomic layer and insight into the double-edged sword effect of PbI2 as an additive. 相似文献
153.
Phenyltrimethylammonium Salts as Methylation Reagents in the Nickel‐Catalyzed Methylation of C−H Bonds
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Takeshi Uemura Mao Yamaguchi Prof. Dr. Naoto Chatani 《Angewandte Chemie (International ed. in English)》2016,55(9):3162-3165
Methylation of C(sp2)?H bonds was achieved through the NiII‐catalyzed reaction of benzamides with phenyltrimethylammonium bromide or iodide as the source of the methyl group. The reaction has a broad scope and shows high functional‐group compatibility. The reaction is also applicable to the methylation of C(sp3)?H bonds in aliphatic amides. 相似文献
154.
Mohan Lakshmi Punna Rao Alapati Sridhar Rao Abburu Krishnaji Rao Mutyala Saratchandra Babu Mukkamala 《合成通讯》2016,46(14):1242-1248
An efficient one-pot synthesis of N-arylbenzamide is described via reaction of phenylboronic acid/aryl bromide with benzamide in the presence of CuI (5 mol%) as catalyst, 4-dimethylaminopyridine (20 mol%) as the ligand, and Cs2CO3 (2 mmol) as the base. This protocol was applied to synthesize a small library of N-arylbenzamide in high yields. 相似文献
155.
Comparative Study of Carbon Paste,Screen Printed,and PVC Potentiometric Sensors Based on Copper‐sulphamethazine Schiff Base Complex for Determination of Iodide – Experimental and Theoretical Approaches
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New poly vinyl chloride (PVC) membrane, carbon paste (CP), and screen printed (SP) electrodes are constructed for iodide sensing. They are based on copper (II)‐sulphamethazine Schiff base complex as suitable carrier. Mechanism was proved by FT‐IR and UV‐Vis spectroscopy. Computational study involving binding energies calculations at DFT/B3LYP level of theory confirmed the proposed mechanism and agreed the observed selectivity pattern. Responses are near‐Nernstian (?55.0, ?51.0 mV/concentration decade) for PVC, and SP electrodes, and super‐Nernstian (?61.2 mV/concentration decade) for the CP electrode. Lower limit of detection (3.2×10?6 mol L?1) and improved selectivity over the highly interfering thiocyanate were obtained in comparison with the previously reported Schiff base complexes‐based iodide sensors. 相似文献
156.
Unprecedented Efficient Structure Controlled Phosphorescence of Silver(I) Clusters Stabilized by Carba‐closo‐dodecaboranylethynyl Ligands
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Michael Hailmann Natalia Wolf Rebecca Renner Thomas C. Schäfer Benjamin Hupp Dr. Andreas Steffen Prof. Dr. Maik Finze 《Angewandte Chemie (International ed. in English)》2016,55(35):10507-10511
{Ag2(12‐C≡C‐closo‐1‐CB11H11)}n and selected pyridine ligands have been used for the synthesis of photostable AgI clusters that, with one exception, exhibit for AgI compounds unusual room‐temperature phosphorescence. Extraordinarily intense phosphorescence was observed for a distorted pentagonal bipyramidal AgI7 cluster that shows an unprecedented quantum yield of Φ=0.76 for AgI clusters. The luminescence properties correlate with the structures of the central AgIn motifs as shown by comparison of the emission properties of the clusters with different numbers of AgI ions, different charges, and electronically different pyridine ligands. 相似文献
157.
本文制备了一系列不同碘含量的板状碘溴化银微晶(微晶大小约为3微米)。运用扫描透射电镜和X射线能谱仪(EDS)对单个微晶进行了分析和研究,半定量地测定了碘离子在板状微晶中的面分布;运用扫描俄歇微区棵针(SAM)和二次电子像、离子溅射剥层技术对微晶进行了表面及其纵深的碘离子的点分析,根据EDS和SAM的结果,可以得到板状碘溴化银微晶中的碘离子的空间分布。实验结果表明在板状缺溴化银微晶中,在其中心部位的碘含量最高;越靠近横向边缘的位置,碘含量越低。且在制备碘溴化银微晶时,如果pAg值较高,将会使在制备早期加入的碘离子通过不断的重结晶向微晶表面扩散,得到的微晶不是夹心结构的碘溴化银微晶。 相似文献
158.
碘在卤化银微晶中的含量和分布对感光度的影响引起乳剂配方设计者的广泛注意和重视.颗粒中的碘引起其内部结构和表面结构的改变,导致微晶颗粒表面化学及物理性质的改变,从而引起增感敏化斑的位置、分布以及随后潜影斑、灰雾斑的形成等一系列的变化并最终影响乳剂的感光性能.如果我们想有效地控制卤化银乳剂的感光度、灰雾、反差等一系列感光性能,必须调整卤化银乳剂颗粒的表面结构. 相似文献
159.
本文制备了一系列结构不同的片状卤化银晶体,用扫描透射电子显微镜和X射线能谱仪相结合的方法对单个微晶进行了亚显微结构分析。半定量地测定了碘离子在不同结构的片状晶体中的分布,同时测量了各样品相应的介电损耗、Dember效应的光电压及高低照互易律失效。结果表明,在四种碘离子分布不同的片状卤化银晶体中,其微晶的离子电导率、高低照互易律失效、Dember效应的光电压衰减都随微晶中碘离子的分布不同而异,而且与乳剂的感光性能有很好的对应关系。 相似文献
160.
A procedure was developed for the synthesis of tertiary phosphine oxides by alkylation of secondary phosphine oxides with
quaternary ammonium salts.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 390–392, February, 1999 相似文献