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1.
Magorzata Katarzyna Cabaj Roman Gajda Anna Hoser Anna Makal Paulina Maria Dominiak 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(8):1036-1044
Crystals of hypoxanthinium (6‐oxo‐1H,7H‐purin‐9‐ium) nitrate hydrates were investigated by means of X‐ray diffraction at different temperatures. The data for hypoxanthinium nitrate monohydrate (C5H5N4O+·NO3?·H2O, Hx1 ) were collected at 20, 105 and 285 K. The room‐temperature phase was reported previously [Schmalle et al. (1990). Acta Cryst. C 46 , 340–342] and the low‐temperature phase has not been investigated yet. The structure underwent a phase transition, which resulted in a change of space group from Pmnb to P21/n at lower temperature and subsequently in nonmerohedral twinning. The structure of hypoxanthinium dinitrate trihydrate (H3O+·C5H5N4O+·2NO3?·2H2O, Hx2 ) was determined at 20 and 100 K, and also has not been reported previously. The Hx2 structure consists of two types of layers: the `hypoxanthinium nitrate monohydrate' layers (HX) observed in Hx1 and layers of Zundel complex H3O+·H2O interacting with nitrate anions (OX). The crystal can be considered as a solid solution of two salts, i.e. hypoxanthinium nitrate monohydrate, C5H5N4O+·NO3?·H2O, and oxonium nitrate monohydrate, H3O+(H2O)·NO3?. 相似文献
2.
A novel organoantimony complex of 6-cyclohexyl-6,7-dihydrodibenzo[c,f] [1,5]azastibocin-12(5H)-yl nitrate ( 2 ) was synthesized and systematically characterized by techniques such as NMR spectra, TG-DSC, and X-ray diffraction. It was found that the complex 2 exhibits relatively strong Lewis acidity (3.3 < Ho ≤ 4.8) and could be employed as a water tolerant Lewis acid catalyst for the synthesis of synthetically valuable benzimidazole derivatives starting from aldehydes and arylenediamines. This catalytic system shows excellent tolerance toward a wide variety of functional groups, such as methyl, methoxyl, fluoro, chloro, bromo, nitro, cyan, trifluoromethyl, 1-naphthaldehyde, furfural and n-butyl, together with facile reusability in 5 times scale enlarged synthesis. 相似文献
3.
Asghar Bodaghi 《先进技术聚合物》2019,30(11):2827-2832
Novel A2B2‐type energetic miktoarm star‐shaped copolymers composed of two PGN arms and two PCL arms was synthesized by the combination of ring‐opening polymerization (ROP) and “click” chemistry. Initially, diazido end‐functionalized two‐arm PGN, (PGN)2‐(N3)2, was synthesized by ROP of glycidyl nitrate monomers. Subsequently, (PGN)2‐(PCL)2 was obtained from the click reaction between diazido end‐functionalized (PGN)2‐(N3)2 polymers and propargyl‐terminated poly(ε‐caprolactone) (PTPCL). This star copolymer solves problems of PCL (lake of energy) and PGN (low Tg). The Fourier‐transform infrared (FT‐IR), 1H nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) studies revealed that (PGN)2‐(PCL)2 was successfully obtained. The thermal behavior of star polymer was investigated by thermogravimetric analysis (TGA) and derivative thermogravimetry. The results show that (PGN)2‐(PCL)2 decomposed at two stages. The first stage is seen at 212.6°C which related to degradation of –ONO2 group and second stage attributed to degradation of PCL group which is seen at 346.1°C. 相似文献
4.
Oxoanionic Noble Metal Compounds from Fuming Nitric Acid: The Palladium Examples Pd(NO3)2 and Pd(CH3SO3)2 下载免费PDF全文
Jörn Bruns Prof. Dr. Thorsten Klüner Prof. Dr. Mathias S. Wickleder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1294-1301
The oxidation of elemental palladium at 100 °C in a mixture of fuming nitric acid and a pyridine‐SO3 complex leads to the anhydrous nitrate Pd(NO3)2 (monoclinic, P21/n, Z=2, a=469.12(3) pm, b=593.89(3) pm, c=805.72(4) pm, β=105.989(3)°, V=215.79(2) Å3). The Pd2+ ions are in square‐planar coordination with four monodentate nitrate groups which are connected to further palladium atoms, leading to a layer structure. The reaction of elemental palladium with a mixture of fuming nitric acid and methanesulfonic acid at 120 °C leads to single crystals of Pd(CH3SO3)2 (monoclinic, P21/n, Z=2, a=480.44(1) pm, b=1085.53(3) pm, c=739.78(2) pm, β=102.785(1)°, V=376.254(17) Å3). Also in this structure the Pd2+ ions are in square‐planar coordination with four monodentate anions; however, the connection to adjacent palladium atoms leads to a chain‐type structure. The thermal decomposition of the compounds has been investigated by means of DSC/TG measurements. Furthermore, IR and Raman spectra have been recorded, and an assignment of the observed vibrational frequencies has been carried out based on theoretical investigations. 相似文献
5.
Xiaoliang Lu Jinzhi Zhou Jinxiu Zhao Prof. Dan Wu Xuejing Liu Prof. Xiang Ren Prof. Qin Wei Prof. Huangxian Ju 《Chemphyschem》2023,24(20):e202300536
The electrocatalytic nitrate reduction reaction (NO3−RR) enables the reduction of nitrate to ammonium ions under ambient conditions. It was considered as an alternative reaction for the production of ammonia (NH3) in recent years. In this paper, we report that the Fe doping CoS2 nanoarrays can effectively catalyze the formation of NH3 from nitrate (NO3−) under ambient conditions. This is mainly due to the increase of the NO3− reaction active site by Fe doping and the porous nanostructure of the catalyst, which greatly improves the catalytic activity. Specifically, at −0.9 V vs. RHE, the NH3 yield rate (RNH3) of Fe−CoS2/CC is 17.8×10−2 mmol h−1 cm−2 with Faraday Efficiency (FE) of 88.93 %. Besides, such catalyst shows good durability and catalytic stability, which provides the possibility for the future application of electrocatalytic NH3 production. 相似文献
6.
在锂-硫化聚丙烯腈电池体系中,负极锂枝晶的形成和生长严重恶化了电池充放电性能,并给电池带来了安全隐患。而在更有利于稳定正极硫化聚丙烯腈材料的碳酸酯类电解液中,锂枝晶生长尤为严重。本文通过将硝酸镁添加到碳酸酯类电解液中,研究硝酸根和镁离子对锂金属表面改性的共同作用。实验数据发现,在硝酸根和镁离子共同作用下,锂枝晶生长被有效抑制。当硝酸镁浓度为100 mmol·L-1时,锂铜半电池的库仑效率明显提高,并显著改善了锂-硫化聚丙烯腈电池的循环性能。300次循环后容量保持率为71%,远高于硝酸锂的61%和无添加剂的50%。 相似文献
7.
《印度化学会志》2021,98(12):100224
Fertilization is the set of operations that consists of fertilizing the soil so that the plant finds all these mineral nutrition needs, among these nutrients is found potassium nitrate (KNO3), as an important source of two elements which are nitrogen (N) and potassium (K). The need for potassium nitrate for plants will increase dramatically as its demand for nutrition growing up. However, the application of this potassium in fertilization is limited by a physicochemical parameter which is solubility. The availability of potassium and nitrogen in ionic form, which can be assimilated by the plant, is closely related to its solubility in irrigation water. Herein, we have chosen three experimental parameters such as the KNO3 content, the magnetization time, and the type of water, to optimize the factors which have the maximum effect on KNO3 solubility.We adopted a model from nine experiments performed with Minitab software, which informed us that the solubility of KNO3 in irrigation water is strongly influenced by water type, magnetization time and KNO3 content. The best conditions which allow the best solubility of potassium nitrate are 24% KNO3, 30 min of water magnetization, and salt water (SW). 相似文献
8.
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
9.
Yttrium(III) Nitrate: A Powerful Catalyst for Green and Rapid Synthesis of Some Supramolecules 下载免费PDF全文
A convenient and rapid procedure for the synthesis of calix[4]resorcinarenes as useful supramolecules has been developed via a reaction of aryl aldehydes with resorcinol in the presence of yttrium(III) nitrate under solvent‐free conditions. This eco‐friendly method has many appealing attributes such as excellent yields, short reactions times, and simple work‐up procedures. 相似文献
10.
硝酸铵的一种敏化技术 总被引:3,自引:0,他引:3
介绍一种在表面活性剂作用下,采用真空改性结晶技术,制备膨松、轻质和多微孔隙硝酸铵的方法。用该硝酸铵混制的铵木油炸药,具有良好的起爆和传爆性能、作功能力大、爆速高,是一种可以取代铵梯炸药,适宜于工业生产和广泛用于工程爆破的炸药。 相似文献