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101.
102.
Ying Liu Ying‐Hui Yu Yi‐Fu Liu Guang‐Feng Hou Xiao‐Dan Wang Bo Wen Jin‐Sheng Gao 《无机化学与普通化学杂志》2013,639(1):193-196
The cage‐like complex, Ag4L4(NO3)4 ( 1 ) [L = 1, 4‐bis(pyridine‐2‐ylmethoxy)benzene] was synthesized by the reaction of the flexible bidentate ligand and silver nitrate. It was characterized by elemental analysis, IR spectroscopy, TG, and single‐crystal X‐ray analysis. Complex 1 is reported as the first cage‐like cluster constructed by four nitrate anions bridging two [2+2] macrocycles. A blue luminescent emission and luminescent enhancement effect are observed in complex 1 . 相似文献
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A mixture of bismuth nitrate pentahydrate and potassium aryltrifluoroborate in toluene under microwave heating at 120 °C for 20 min provides an interesting and mild reaction protocol for the synthesis of aryl nitrite. The conversion to aryl nitrites from aryltrifluoroborates without transition metal catalyst and base in high yields is remarkable. 相似文献
107.
REN Shi-biao SHEN Zhou ZHANG Ping WANG Zhi-cai LEI Zhi-ping PAN Chun-xiu KANG Shi-gang SHUI Heng-fu 《燃料化学学报》2014,42(5):591-596
以硝酸镍和乙酸镍为镍前体,用浸渍法分别在空气和氢气氛围活化制得系列Ni/SBA-15催化剂,通过XRD、H2-TPD、N2物理吸附和在线质谱等物理化学手段对催化剂进行了表征,并结合微型高压反应釜萘加氢反应,评价了催化剂的加氢性能。结果表明,氢气氛围活化对硝酸镍为镍前体所制Ni/SBA-15催化剂的镍分散度和活性有显著促进作用,而空气氛围活化对乙酸镍为镍前体所制催化剂有明显促进作用。根据催化剂前体在不同氛围活化时的热分解产物,提出了活化氛围对不同镍前体制得Ni/SBA-15催化剂所产生的作用机理。 相似文献
108.
Guang‐Ming Liang Jing Shang Kun‐Guo Yang Kai Ma Qing‐Ling Ni 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(4):379-383
The title compounds, bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ2N1:P}disilver bis(perchlorate) acetonitrile monosolvate, [Ag2(C18H17N2P)2](ClO4)2·CH3CN, (1), and bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ2N1:P}bis[(nitrato‐κ2O,O)silver], [Ag2(C18H17N2P)2(NO3)2], (2), each contain disilver macrocyclic [Ag2(C18H17N2P)2]2+ cations lying about inversion centres. The cations are constructed by two N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine (DPP) ligands linking two Ag+ cations in a head‐to‐tail fashion. In (1), the unique Ag+ cation has a near‐linear coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands. Two ClO4− anions doubly bridge two metallomacrocycles through Ag...O and N—H...O weak interactions to form a chain extending in the c direction. The half‐occupancy acetonitrile molecule lies with its methyl C atom on a twofold axis and makes a weak N...Ag contact. In (2), there are two independent [Ag(C18H17N2P)]+ cations. The nitrate anions weakly chelate to each Ag+ cation, leading to each Ag+ cation having a distorted tetrahedral coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands, and two chelating nitrate O atoms. Each dinuclear [Ag2(C18H17N2P)2(NO3)2] molecule acts as a four‐node to bridge four adjacent equivalent molecules through N—H...O interactions, forming a two‐dimensional sheet parallel to the bc plane. Each sheet contains dinuclear molecules involving just Ag1 or Ag2 and these two types of sheet are stacked in an alternating fashion. The sheets containing Ag1 all lie near x = , , etc, while those containing Ag2 all lie near x = 0, 1, 2 etc. Thus, the two independent sheets are arranged in an alternating sequence at x = 0, , 1, etc. These two different supramolecular structures result from the different geometric conformations of the templating anions which direct the self‐assembly of the cations and anions. 相似文献
109.
Jens Rudlof Niklas Aders Dr. Jan-Hendrik Lamm Beate Neumann Dr. Hans-Georg Stammler Prof. Dr. Norbert W. Mitzel 《ChemistryOpen》2021,10(10):1020-1027
Starting from 1,2-diethynylbenzene, a series of bidentate Lewis acids was prepared by means of hydrometalations, in particular hydrosilylation, hydroboration, hydroalumination and terminal metalation based on group 13 and 14 elements. In the case of terminal alkyne metalation, the Lewis-acidic gallium function was introduced using triethylgallium under alkane elimination. A total of six different Lewis acids based on a semiflexible organic scaffold were prepared, bearing −SiClMe2, −SiCl2Me, −SiCl3, −B(C6F5)2, −AlBis2 (Bis=bis(trimethylsilyl)methyl) and −GaEt2 as the corresponding functional units. In all cases, the Lewis acid functionalisation was carried out twice and the products were obtained in good to excellent yields. In the case of the twofold gallium Lewis acid, a different structural motif in the form of a polymer-like chain was observed in the solid state. All new bidentate Lewis acids were characterised by multinuclear NMR spectroscopy, CHN analysis and X-ray diffraction experiments. 相似文献
110.
A direct, reagent-free, ultraviolet spectroscopic method for the simultaneous determination of nitrate (NO3−), nitrite (NO2−), and salinity in seawater is presented. The method is based on measuring the absorption spectra of the raw seawater range of 200–300 nm, combined with partial least squares (PLS) regression for resolving the spectral overlapping of NO3−, NO2−, and sea salt (or salinity). The interference from chromophoric dissolved organic matter (CDOM) UV absorbance was reduced according to its exponential relationship between 275 and 295 nm. The results of the cross-validation of calibration and the prediction sets were used to select the number of factors (4 for NO3−, NO2−, and salinity) and to optimize the wavelength range (215–240 nm) with a 1 nm wavelength interval. The linear relationship between the predicted and the actual values of NO3−, NO2−, salinity, and the recovery of spiked water samples suggest that the proposed PLS model can be a valuable alternative method to the wet chemical methods. Due to its simplicity and fast response, the proposed PLS model can be used as an algorithm for building nitrate and nitrite sensors. The comparison study of PLS and a classic least squares (CLS) model shows both PLS and CLS can give satisfactory results for predicting NO3− and salinity. However, for NO2− in some samples, PLS is superior to CLS, which may be due to the interference from unknown substances not included in the CLS algorithm. The proposed method was applied to the analysis of NO3−, NO2−, and salinity in the Changjiang (Yangtze River) estuary water samples and the results are comparable with that determined by the colorimetric Griess assay. 相似文献