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991.
Solution Layer Deposition: A Technique for the Growth of Ultra‐Pure Manganese Oxides on Silica at Room Temperature 下载免费PDF全文
Dr. Jérémy Cure Dr. Kilian Piettre Dr. Yannick Coppel Dr. Eric Beche Dr. Jérôme Esvan Vincent Collière Dr. Bruno Chaudret Dr. Pierre Fau 《Angewandte Chemie (International ed. in English)》2016,55(9):3027-3030
With the ever increasing miniaturization in microelectronic devices, new deposition techniques are required to form high‐purity metal oxide layers. Herein, we report a liquid route to specifically produce thin and conformal amorphous manganese oxide layers on silicon substrate, which can be transformed into a manganese silicate layer. The undesired insertion of carbon into the functional layers is avoided through a solution metal–organic chemistry approach named Solution Layer Deposition (SLD). The growth of a pure manganese oxide film by SLD takes place through the decoordination of ligands from a metal–organic complex in mild conditions, and coordination of the resulting metal atoms on a silica surface. The mechanism of this chemical liquid route has been elucidated by solid‐state 29Si MAS NMR, XPS, SIMS, and HRTEM. 相似文献
992.
《中国化学》2017,35(8):1311-1316
Specific recognition of ultratrace levels of ions in semi‐water using super‐quicker methods is still a challenge for environmental monitoring. Herein we report a fluorescent and colormetric sensor ( ZH ) based on supramolecular self‐assembly, whose structure was destroyed by the addition of ultratrace of silver ions. The process promoted either naked eye visible color changes or fluorescence intensity quenched in conjunction with a wide pH range. Systematic studies revealed very high selectivity (0.07 µmol/L) for silver ions, and other common cations, e.g ., Hg2+, Cu2+, Cd2+, Pb2+ had nearly no influence on the sensing behavior. This sensor also served as a multiple use of component in sensing materials by addition of I− into the mixture of ZH and Ag+ (about 5 times). What's more, ZH containing filter paper emerged distinct color and fluorescence changes upon exposure to silver (Ag+), which could be used as a portable method to undertake field testing for Ag + . 相似文献
993.
In this work, we synthesised and characterised three novel fluorescence macrocyclic sensors containing optically active dansyl groups. The studies for the interaction of the synthesised compounds with various mental ions (Li+, Na+, K+, Ag+, Mg2+, Ca2+, Ba2+, Pb2+, Zn2+, Co2+, Cd2+, Hg2+, Ni2+, Cu2+, Mn2+, Cr3+, Al3+, Fe3+) were performed by fluorescence titration, Job’s plot, ESI-MS and DFT calculations. The results showed that the sensors 1a–1c displayed selective recognition for Cu2+ and Fe3+ ions and formed stoichiometry 1:1 complex through PET mechanism in DMSO/H2O solution (1:1, v/v, pH 7.4 of HEPES). The binding constant (K) and detection limit were calculated. 相似文献
994.
ZnCl_2溶液中微波辅助SnCl_4催化纤维素制备5-HMF 总被引:1,自引:0,他引:1
ZnCl溶液中微波辅助SnCl催化纤维素制备-HMF 《燃料化学学报》2017,45(3):317-322
将纤维素溶解在ZnCl_2溶液中,以SnCl_4为催化剂,微波下使纤维素降解成5-羟甲基糠醛(5-HMF)。实验考察了微波功率、纤维素的质量、ZnCl_2溶液浓度、反应时间及催化剂与纤维素物质的量比等对5-HMF产率的影响。结果表明,以SnCl_4为催化剂,在优化条件:1.0 g纤维素溶解在100 m L 70%ZnCl_2溶液中,微波功率为420 W,降解反应9 min,SnCl_4与纤维素物质的量比2∶1下,5-HMF的产率达到39.4%。 相似文献
995.
Joanna Kobyłecka Bogdan Ptaszyński Anna Zwolinńska 《Monatshefte für Chemie / Chemical Monthly》2000,131(1):1-11
Summary. Sparingly water soluble complexes of lead(II), cadmium(II), and zinc(II) with N-phosphonomethylglycine (glyphosate, NPMG) of the general formulae C3H6O5NPPb, C3H6O5NPCdċ2H2O, and C3H6O5NPZn were synthesized. The complexes were also precipited from a dilute Roundup solution, and their solubility in water was
determined. Thermal, diffractometric, and IR spectrophotometric analyses were carried out. It was found that the metal is
bonded to glyphosate through the oxygen atoms of the carboxylic and phosphonate groups; metal-nitrogen binding is absent in
the above compounds. Studying the complexing behaviour in solution by UV spectrophotometry pointed out that a complex of the
composition Pb(II) : NPMG=1:1 with an absorption band at 232 nm is formed. Its stability constant as determined by Job’s method is logK=5.9±0.1. Using potentiometric techniques, the dissociation constant of N-phosphonomethylglycine and the stability constants
of its complexes with cadmium (II) and zinc (II) were determined.
Received June 30, 1999/Accepted July 21, 1999. 相似文献
996.
997.
通道离子替换磷灰石固溶体比较晶体化学XRD研究 总被引:3,自引:0,他引:3
采用单相共沉淀法和隋性气体保护下的固相反应法制备了不同通道离子替换固溶体磷灰石[X1-X2AP]。利用XRD对通道离子替换磷灰石固溶体进行了比较晶体化学研究,结果表明:晶胞参数随通道离子半径的增大,a0增大,c0反而减小,且OH-ClAP和F-OHAP变化呈线性关系,符合Vegard定律,而F-ClAP在富F-端的变化不呈线性关系;由于[PO4]四面体沿[101]方向的滑移,c0随a0的变化而变化,且c0-2与a0-2呈线性关系[c0-2=-a0-2+3.2348]。 相似文献
998.
聚N,N-二乙基丙烯酰胺溶液粘度的温度依赖性 总被引:2,自引:0,他引:2
通过自由基聚合,合成了线型聚N,N-二乙基丙烯酰胺(PDEA),用乌氏粘度计测定并考察了该聚合物在四氢呋喃(THF)、H2O以及THF-H2O混合溶剂中粘度的温度依赖性.实验结果表明,PDEA 在上述三种溶剂中粘度的温度依赖性不同,PDEA-THF体系的相对粘度随温度升高而增大;PDEA-H2O体系以及PDEA-THF-H2O体系的相对粘度随温度升高而减小,且THF体积分数φTHF < 0.7时具有透明-白浊转变现象;对PDEA-THF-H2O体系,φTHF增加,透明-白浊转变温度升高,而当φTHF=0.7时,则观察不到透明-白浊转变现象. 相似文献
999.
1000.