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991.
Pseudoelement Compounds. XI. [1] Investigations on the Coordination Behaviour of Cyanamidonitrate [NO2NCN]? With the ionic, potentially ambidentate ligand cyanamidonitrate complexes of the types [MX(PPh3)3], [MX(PPh3)2]2 (M?CuI, AgI) and trans-[Pt(H)X(PPh3)2] (X??[NO2NCN]?) are introduced. The new compounds are characterized by 1H NMR, 31P NMR, and IR spectroscopy. The crystal structures of [Cu(NO2NCN)(PPh3)2]2 and [Ag(NO2NCN)(PPh3)2]2 are reported. In the complexes [MX(PPh3)3] and trans-[Pt(H)X(PPh3)2] cyanamidonitrate is unidentately coordinated through the nitrile group end-on. In the dimeric complexes [MX(PPh3)2]2 the anion acts bidentately as a bridging ligand. Surprisingly, both coordinative bonds are formed through nitrogen atoms of the NCN group. 相似文献
992.
SONG Rui-Feng 《结构化学》2005,(11)
1 INTRODUCTION Metallosupramolecular species with metal-metal interactions have been designed and synthesized due to their potential applications as functional materi- als[1]. For Ag(I) coordination compounds, short Ag(I) –Ag(I) separations have been found in many bi- and polynuclear complexes[2~4], and these short metal- metal distances have been attributed to the ligand ar- chitecture[5, 6]. Thus, the rational design of bi- and polynuclear Ag(I) complexes must recognize the in- here… 相似文献
993.
The preparation and the releasing behavior of modified silica coatings, containing embedded biocides on textiles, were compared and assessed with regard to application parameters like antimicrobial efficacy, wash-out and long-term behavior. For this, silica layers with embedded silver, silver salts and biocidal quaternary ammonium salts (cetyltrimethylammoniumbromid and octenidine) were investigated. Both the growth of fungi and bacteria can be inhibited by coatings with embedded biocides. Especially by using octenidine, an excellent long-term inhibition of fungi growth can be reached. 相似文献
994.
Chang Yin LU Zhi Hui HAN Sheng Yuan YANG 《中国化学快报》2005,16(8):1063-1066
A novel determination method of Ag^+ was established. In acetic acid-sodium acetate buffer (pH 5.0) medium, Ag^+ reacts with SCN^- to form AgSCN in the presence of TritonX-100,which results in an increase of resonance light scattering (RLS)and giving a new RLS spectrum.The maximum RLS peak was at 585 nm,The enhancement of resonance light scattering at 585 nm was proportional to the concentration of Ag^+ ranging from 0.0045-4.00μg mL^-1 (r=9991),and the detection limit was 1.37 ng mL^-1 with the recovery of 97.70%- 104.80%。 相似文献
995.
Two procedures are proposed for the potentiometric determination of Ag(I), Pd(II) and Au(III) in binary mixtures, by titration with potassium iodide solution, and use of a commercial iodide electrode as sensor. In the first procedure, two aliquots of the mixture are titrated, at pH 2.0 ± 0.2 and 9.0 ± 0.2, adjusted with dilute sulphuric acid and ammonia solution. At pH 2.0, the titrant reacts with both metals, whereas at pH 9.0, Ag(I) is the only reactant. The second procedure utilizes titration of two aliquots of the mixture in the presence and absence of a selective masking agent. The methods have been applied to the determination of these metals in some jewellery alloys. 相似文献
996.
《中国化学》2018,36(2):147-152
One‐pot two‐step stepwise reaction of terminal propargylic alcohols, carbon dioxide, and primary/secondary amines for the effective synthesis of various urethanes through robust silver‐catalysed C‐O/C‐N bond formation is reported. Catalytic activities were investigated by controlling catalyst loading, reaction pressure and time, and very high turnover number (turnover frequency) was obtained: 3350 (35 h−1) with 0.01 mol% silver catalyst under 0.1 MPa, and up to 13360 (139 h−1) with 0.005 mol% silver catalyst under 2.0 MPa at room temperature. The strategy was ingeniously regulated, and synchronously afforded a wide range of β‐oxopropylcarbamate and 1,3‐oxazolidin‐2‐one motifs in excellent yields and selectivity together with unprecedented high turnover number (TON) and turnover frequency (TOF) value. 相似文献
997.
Inside Cover: Beyond Clusters: Supramolecular Networks Self‐Assembled from Nanosized Silver Clusters and Inorganic Anions (Chem. Eur. J. 20/2016)
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998.
Frontispiece: Silver Nanoparticles Supported on CeO2‐SBA‐15 by Microwave Irradiation Possess Metal–Support Interactions and Enhanced Catalytic Activity
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999.
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