New family of solid sorbents for adsorptive cooling: Material scientist approach

This paper summarizes literature data concerning a new family of materials for adsorptive cooling. They are composites of a type of “salt confined to a porous host matrix” (so called selective water sorbents or SWSs). These materials demonstrate an intermediate behavior between solid adsorbents, salt hydrates, and liquid absorbents. The thermodynamic equilibrium with water vapor has been measured for more than thirty SWSs based on halides, sulphates, and nitrates of alkaline and alkaline earth metals that are confined to various matrices (silica, alumina, porous carbons, clays, MCM-41, etc.). The important advantage of the SWSs is the possibility to controllably modify their water sorption properties in a wide range by varying (a) the chemical nature of the impregnated salt, (b) the porous structure of the host matrix, (c) the amount of the confined salt, and (d) the preparation conditions. This, in principle, allows purposeful synthesis of new solid sorbents with predetermined properties that fit the demands of particular adsorptive cycles. Appropriate examples are presented in the paper. A recent study of adsorption chillers with granulated and compact layers of SWS-1L (CaCl₂ in mesoporous silica) showed an experimental COP as high as 0.6, which is larger than that reported for silica gel/water and zeolite/water systems under the same cycle conditions. The concept of matrix modification with an active salt can also be used for synthesis of efficient sorbents of carbon dioxide, methanol, and ammonia. Other practical applications of SWSs are briefly discussed, such as heat protection, gas drying, and fresh water production from the atmosphere. The text was submitted by the author in English.     

A new convenient synthesis of aroyl cyanides via the formation of cyanohydrin nitrate intermediates

The treatment of α-bromoarylacetonitriles with AgNO₃ generates cyanohydrin nitrate intermediates, which easily eliminate nitrous acid with the formation of carbonyl bond to afford aroyl cyanides in good to high yields.     

钝化芳环的硝化研究进展*

芳香族化合物的硝化反应是工业生产中重要的单元反应,钝化芳环的硝化反应在医药、农药、染料和炸药合成中有重要地位。本文从硝化试剂角度综述了近年来钝化芳环的硝化反应的进展,包括硝酸盐/硫酸、硝酸酯、硝酸、氮氧化物等硝化方法。简要评述了这些方法的特点,并展望了硝化方法的研究方向。其中,硝酸盐/硫酸体系具有较强的硝化能力,对于钝化芳环,可以在温和条件下以高收率得到硝化产物,在实验室制备或工业应用中具有较高的应用价值;其他硝化方法由于各种原因暂时不能对钝化程度较高的芳环进行硝化,还需进一步研究具有较高活性的硝化体系。     

Complexes of lanthanide nitrates with 2-N-(6-picoIyl)-benzamide

New complexes of lanthanide nitrates with 2-N-(6-picolyl)-benzamide of the formulae Ln₂[6-pic-BA], [NO₃l₆ (Ln = Y and La-Yb) have been prepared and characterised by chemical analysis, infrared, molar conductance and electronic spectral data. Molar conductance data along with IR data point to the presence of co-ordinated nitrate groups. IR spectra prove the bidentate co-ordination of the ligand to the metal ion, through the oxygen of the secondary amide and the nitrogen of the heterocyclic ring. Electronic spectral studies in the visible region suggest an eight co-ordinate geometry around the metal ions.     

Action of monoatomic cations on the structure and spectra of Mx(1)M1-x(2)UO2(NO3)3 crystals

The action of the monovalent M⁺ cations on the luminescent properties of the mixed M _x ⁽¹⁾ M _1-x ⁽²⁾ UO₂(NO₃)₃ crystals, where M is Na, K, Rb, Cs, or NH₄ , has been investigated. It has been established that the spectral positions of the bands of vibronic transitions depend linearly on the ratio between the concentrations of the M⁽¹⁰⁾ and M⁽²⁾ cations. It is shown that the crystals considered are composed of l[RbUO₂(NO₃)₃]n[CsUO₂(NO₃)₃] clusters, where l/n = x/(1 - x). The spectral regularities revealed are determined by the partial contributions of the M⁽¹⁾ and M⁽²⁾ cations to their combined, polarizing action on the uranyl complex and are explained by the ligand nature of its highest occupied molecular orbital.Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 71, No. 6, pp. 827–830, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date.     

重稀土硝酸盐与单N-乙酸取代O_2N_2大环配合物的合成与表征

本文合成了二种稀土硝酸盐与1,12-二氮杂-3,4:9,10-二苯并-5,8-二氧杂环-N-乙酸(HL)的配合物。通过红外,远红外光谱,元素分析、ICP测定,电导分析测试手段,确定了配合物的组成为REL(NO_3)_2·2H_2O(RE=Yb、Dy),并研究了它们的性质。     

Schiff碱双冠醚和稀土硝酸盐配位行为的研究

迄今为止,研究稀土冠醚配合物所用的配体都是分子中含一个冠醚环的单冠醚化合物,配体中含有两个冠醚环的双冠醚稀土配合物还未见到报道。Handside于1982年报道了一系列结构式为右边所示的Schiff碱双冠醚。本文报道m=2,n=2的Schiff     

钪、钇硝酸盐与邻菲啰啉单氮氧化物形成配合物的研究

本文合成出组成为M(PhenNO)_n(NO_3)_3(M=Sc、Y∶n=1,2)的4种配合物.通过元素分析、红外光谱、紫外光谱、摩尔电导、溶解性、TG和DSC研究了配合物的有关性质.     

New crystal modification of the di(nitrato)di(aqua)palladium(II) complex β-trans-[Pd(NO3)2(H2O)2]

Single crystals of a new modification of the di(nitrato)di(aqua)palladium(II) complex β-trans-[Pd(NO₃)₂(H₂O)₂] were obtained. Their crystal structure was determined: monoclinic crystal system, a = 5.7469(4) Å, b = 5.3942(6) Å, c = 10.0956(10) Å, β = 97.401(3)°, P2₁/c, Z = 2, d _calc = 2.851 g/cm³, Bruker X8 APEX CCD, MoK _α , 836 independent reflections, room temperature. The square-plane coordination of the Pd atom is formed by four oxygen atoms (Pd-O(NO₃) 2.003(3) Å and Pd-O(H₂O) 2.021(4) Å) and completed to a distorted bipyramid by two intramolecular contacts (Pd…O(NO₃) 2.893 Å). A comparative crystal-chemical analysis with α-trans-[Pd(NO₃)₂(H₂O)₂] was carried out.