Complexes of some 3d metal ions of the Schiff's base,N,N′-di-4-(4′-pentyloxybenzoate) salicylidene-1″, 3″-diamino-2″-propanol: Synthesis and spectral studies

A nematogenic Schiff's base, N,N′-di-4-(4′-pentyloxybenzoate)salicylidene-l″, 3″-diamino-2″-propanol, (abbreviated as H₂L⁶), was synthesized and its structure studied by elemental analyses, mass, NMR and IR spectra. The Schiff's base behaves as a dinegative hexa/tetradentate species in its metal complexes of the general formula, [ML⁶]_n where M^II═Mn, Co, Ni, Cu and Zn. Their structural characterizations were made by various spectroscopic techniques.     

Mössbauer studies of α″-Fe16N2 and α′-Fe8N films

Conversion-electron Mössbauer spectra of epitaxial -Fe₁₆N₂ and -Fe₈N films have been studied and their differences are discussed in detail. The Mössbauer spectrum of -Fe₁₆N₂ can be decomposed into three subspectra, which correspond to the 4d, 8h and 4c sites. The Mössbauer spectrum of -Fe₈N can be fitted using four spectra based on a nitrogen-atom-random-distribution model. The average hyperfine field is larger (3%) for -Fe₁₆N₂ than for -Fe₈N, which is approximately consistent with a 4.1% enhancement of the magnetic moments for -Fe₁₆N₂. The iron moments tend to locate in the film plane for -Fe₁₆N₂ and to arrange perpendicularly to the film plane for -Fe₈N.     

A simple and effective synthesis of cadmium selenide in aqueous N,N′-dimethylformamide

Cadmium selenide has been synthesized directly from cadmium chloride in aqueous N,N′-dimethylformamide (DMF) by the use of cycloocteno-1,2,3-selenadiazole or the element itself as the source of selenium. The dark brown powders that are the end-products of these reactions were characterized by reflectance spectroscopy, powder X-ray diffraction and scanning electron microscopy.     

N,N′-二己基对苯二胺的合成

以对苯二胺为起始反应物,利用取代N-烷基化方法,与1-溴己烷进行直接烷基化反应,通过元素分析和光谱分析,证实了合成产物为N,N′-二己基对苯二胺,反应产物收率大于60%,单N-己基化选择性达到100%。     

Potentiometric studies of N,N′-Bis(2-dimethylaminoethyl)-N,N′-dimethyl-9,10 anthracenedimethanamine as a chemical sensing material for Zn(II) ions

A liquid membrane based Zn²⁺ ion selective electrode containing N,N′-Bis(2-dimethylaminoethyl)-N,N′-dimethyl-9,10 anthracenedimethanamine (Bis(TMEDA) anthracene) (I) as ionophore has been prepared and characterized. The membrane comprises of PVC, ionophore and plasticizer in the ratio of 33:2:65, respectively. It showed the best response in terms of detection limit (1.5 × 10^− 6 M) and working concentration range (1.0 × 10^− 5 M to 1.0 × 10^− 1 M) with Nernstian response towards Zn²⁺ ions. The electrode responds within 15 s of coming in contact with the solution. The potential response remains almost unchanged over a pH range of 3.0 to 7.5. The electrode can be used for at least 3 months without any considerable alteration in its response behavior. The proposed electrode revealed good selectivity towards Zn²⁺ ions over a number of alkali, alkaline earth, transition metals and some other heavy metal ions. The electrode has been used as an indicator electrode in the potentiometric titration of Zn²⁺ with EDTA. The proposed electrode also detected Zn²⁺ ions from real life samples.     

N,N′-4,4′-二苯甲烷双马来酰亚胺的合成工艺与应用

综述了合成N,N′-4,4′-二苯甲烷双马来酰亚胺(BDM)的醋酐脱水法、共沸蒸馏法、及其他改进工艺存在的问题。指出未来产品合成工艺采用一步法,就能够满足国内研发多功能的产品对收率、性能、合成成本、污染控制等方面的需求。     

过硫酸盐漂白液中N,N,N′,N′—四甲基对苯二胺促漂作用机理

一、引言过硫酸盐,由于其标准电位高(2. 01伏),至今仍是人们颇愿使用的一种漂白剂。但实际上,它是一种弱的漂银剂。为此,人们曾做过多种努力,试图用各种补加剂来为过硫酸盐漂银创造催化条件。业已报道过可以使用的补加剂有:鎓盐、芳胺及硫醇等化合物。     

Kinetic study of the aqueous electropolymerization of acrylamide,acrylonitrile andN,N′-methylene-bisacrylamide on an aluminium alloy cathode

This study concerns the potassium persulphate electroinitiated polymerization of acrylamide, acrylonitrile andN, N-methylene-bisacrylamide on a 5182 aluminium-magnesium alloy. Kinetic studies of the polymerization gave the polymerization as -d[M]/dt=K(CD)^0.99 [Persulphate]^1.12 [M]^2.33, whereCD is current density (mA cm^–2), [M] is monomer concentration (mol cm^–3),K is a constant andt is time (s). It is proposed that the thick swollen polymer coating restricted the diffusion of monomers and initiators to the electrode. The problem of mass transfer by diffusion in the present system was confirmed by measurements of the diffusion coefficient and by electron transfer fraction experiments carried out through the use of a cyclic voltammetry technique.     

N,N′,N″-三叔丁基-1,3,5-苯基-三酰胺成核改性聚丙烯

研究了N,N′,N″-三叔丁基-1,3,5-苯基-三酰胺成核剂对聚丙烯光学性能、力学性能、结晶形态、熔融和结晶行为的影响,结果表明,加入该成核剂使聚丙烯的雾度大幅度下降,光泽度大幅度提高;弯曲模量提高,拉伸强度和缺口冲击强度变化不大;球晶尺寸大大减小;熔点、结晶温度和结晶度提高。     

Synthesis and characterization of lanthanide(III) complexes with a mesogenic Schiff-base,N,N′-di-(4-decyloxysalicylidene)-2′,6′-diaminopyridine

A mesogenic Schiff-base, N,N′-di-(4-decyloxysalicylidene)-2′,6′-diaminopyridine, H₂ddsdp (abbreviated as H₂L³) that exhibits nematic mesophase, was synthesized and its structure studied by elemental analysis, mass spectrometry, NMR & IR spectral techniques. The Schiff-base, H₂L³, upon condensation with hydrated lanthanide(III) nitrates, yields Ln^III complexes of the general composition [Ln₂(L³H₂)₃(NO₃)₄](NO₃)₂, where Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy and Ho. Among the metal complexes, only that of Ho^III is found to be mesogenic with smectic-X and nematic phases. The IR and NMR spectral data imply a bi-dentate bonding of the Schiff-base in its zwitterionic form (as L³H₂) to the Ln^III ions through two phenolate oxygens, rendering the overall geometry of the complexes to seven-coordinated polyhedron, possibly distorted mono-capped octahedron.     

Synthesis of carboxylate derivatives of molybdenum and tungsten based on joint insertion of CO2 and PhNCS or N, N′-dicyclohexylcarbodiimide into M-Cl bonds

Reactions of the higher molybdenum and tungsten chlorides with phenyl isothiocyanate or with N, N′-dicyclohexylcarbodiimide and carbon dioxide in dichloroethane are the first to demonstrate the possibility of insertion of carbon dioxide in combination with other heterocumulenes into transition metal-halogen bonds. IR spectroscopy and elemental analysis data show that the reactions result in the attachment of the ligands at the same metal-chlorine bond and the formation of heteromolecular insertion products with the compositions $$\left[ {MoOCl_3 \left\{ {N\left( {Ph} \right)C\left( S \right)} \right\}_2 Nc\left( {Me} \right)Cl} \right]$$ and $$MCl_x \left\{ {OC\left( O \right)\left[ {\left( {Hex} \right)NCN\left( {Hex} \right)} \right]_2 } \right\}Cl,$$ where x = 4 and 5 for the Mo and W derivatives, respectively.     

新型空穴传输材料N,N′-二(α-萘基)-N,N′-二苯基-4,4′-联萘胺的合成与光电性质

以4,4′-联萘胺为母体,以最常用的空穴传输材料N,N′-二(α-萘基)-N,N′-二苯基-4,4′-联苯胺(α-NPD)为样板,合成了新型空穴传输材料N,N′-二(α-萘基)-N,N′-二苯基-4,4′-联萘胺(α-NPN)。通过核磁共振氢谱和元素分析进行了结构表征。差热分析测定其玻璃化温度(Tg)达到128℃。相对于α-NPD,α-NPN的吸收光谱和光致发光光谱都发生了红移。循环伏安法测定其氧化电势为1.20V,比α-NPD的1.02V稍高。该化合物可发明亮的蓝色荧光(461 nm),积分球测定其薄膜荧光量子效率为8.5%,比α-NPD的5.5%高。初步确定α-NPN可作为有机电致发光空穴传输材料。     

Two-dimensional charge-transfer molecules for second-order non-linear optics: synthesis, characterization and second harmonic generation of N,N′-dialkyl-2,4-dinitro-1,5-diaminobenzene compounds

Two-dimensional charge-transfer molecules based on N,N-dialkyl-2,4-dinitro-1,5-diaminobenzene have been synthesized. 1H and 13C-NMR spectroscopy, elemental analysis and mass spectroscopy were used to elucidate their chemical structures. The physical and non-linear optical properties of this new family of dyes containing alkyl chain; C3H7, C6H13, C8H17, C10H21, C11H23 and C18H37 are discussed, taking into account the possible role of alkyl chain length. These two-dimensional molecules have a significantly large off-diagonal component in contrast to one-dimensional molecules. These compounds showed no powder second-harmonic generation (SHG) at 1.064 m being centrosymmetric, however, their poled guest-host systems with poly(methyl methacrylate) and co-crystals with p-nitroaniline were SHG active. Powder SHG as high as 37 times that of urea was observed from N,N-dihexyl-2,4-dinitro-1,5-diaminobenzene with its mixture with p-nitroaniline. Second-harmonic generation of N,N-dioctadecyl-2,4-dinitro-1,5-diaminobenzene (DIODD) was studied as Langmuir–Boldgett monolayers. The Langmiur–Blodgett monolayer of a 1: 1 mixture of DIODD and arachidic acid showed second-order non-linear optical coefficients d11 and d13 of 11 × 10–9 and 3.85 × 10–9 esu, respectively, at a tilt angle of 60°. For the first time, a relationship between the microscopic polarizabilities and the molecular orientation of two-dimensional charge-transfer molecules has been established. In the light of the present experimental and theoretical data analysis, the potential of two-dimensional charge-transfer molecules for second-order non-linear optics is discussed.     

N,N′-二苯基丁二酰胺诱导生成β晶型等规聚丙烯

研究了酰胺化合物——N,N′-二苯基丁二酰胺(DPS)的用量和结晶温度对聚丙烯中β晶型含量和结晶度的影响。发现DPS是聚丙烯的高效β成核剂,随着DPS含量的增加,聚丙烯中β晶型含量不断增多。等温结晶试验表明,添加0.2%DPS的聚丙烯样品在结晶温度为120℃时生成最大含量β晶型,此时β晶型的相对含量达到89.06%。     

Synthesis of cubic boron nitride using Mg and pure or M′-doped Li3N,Ca3N2 and Mg3N2 with M′=Al,B, Si,Ti

The growth pressure-temperature region of cubic boron nitride (cBN) in the systems Mg-BN and MxNy-BN (MxNy=Li₃N, Ca₃N₂, Mg₃N₂) has been redetermined using well-crystallized hexagonal BN (hBN) with low oxygen content (0.2%) as the starting material. The data on the MxNy-BN systems are compatible with the existence of two growth regions: a high-temperature region where cBN grows from a liquid phase, and a low-temperature region where cBN forms from solid-solid reactions. Previous data are discussed according to this model and possible solid-state reactions are proposed on the basis of thermodynamic considerations. The results for the Mg-BN system confirm the effect of the O₂ content of the starting BN on the cBN growth region. The systems (MxNy + M)-BN (M=Al, B, Si, Ti) have been shown to produce cBN crystals of increased size and improved morphology (more compact and perfect) compared to those obtained with the MxNy-BN systems. Their colour is dark or black and their size reaches 0.6 mm. The effect of the relative proportions of M and MxNy on the growth region and yield has been determined and is discussed on the basis of the chemical reactions likely to occur.     

Determination of vapour pressure and standard enthalpies of sublimation and vapourisation of N,N′-ethylenebis(2,4-pentanedion-iminoato)nickel(II) by a TG-based transpiration method

In order to identify a volatile metallo-organic precursor for the deposition of nickel films for CVD applications, equilibrium vapour pressure (p_e) measurements were carried out on a N,N′-ethylenebis(2,4-pentanedion-iminoato)nickel(II) (Ni[(acac)₂en]) by employing a TG-based transpiration method over the range 406 to 495 K leading to values of 118.0±4.1 and 83.3±3.8 kJ mol⁻¹ for the standard enthalpies of sublimation and vapourisation, respectively of Ni[(acac)₂en]. From the plot of log p_e against 1/T, the melting point was derived to be 463 K, which is in reasonable agreement with 469±3 K reported in the literature and was also observed in DTA and melting point studies.     

Interdiffusion of rare-earth cations in Ln1−x ′Ln x ″ Ba2Cu3O7 − δ (Ln′, Ln″ = Y, Dy, Ho) High-T c superconductors

The Y³⁺/Ho³⁺, Y³⁺/Dy³⁺, and Dy³⁺/Ho³⁺ interdiffusion coefficients in the YBa₂Cu₃O_{7 ? δ}-HoBa₂Cu₃O_{7 ? δ}, YBa₂Cu₃O_{7 ? δ}-DyBa₂Cu₃O_{7 ? δ}, and DyBa₂Cu₃O_{7 ? δ}-HoBa₂Cu₃O_{7 ? δ} systems have been determined in air at a temperature of 1233 K by the Boltzmann-Matano method from the yttrium/holmium, yttrium/dysprosium, and dysprosium/holmium concentration profiles across the diffusion zone between two pellets of the high-T _c superconductors. The composition dependences of the interdiffusion coefficients in the solid-solution systems are presented.     

Diffraction studies of β″-magnesium sialon

The compositions of high magnesium content -magnesium sialon crystals within the 3M/4X plane of the Mg-Si-Al-O-N system indicate some form of metal atom ordering wihtin the structure. Although it is not possible using X-ray diffraction to detect weak additional reflections arising from the ordering between magnesium, aluminium, and silicon atoms, such weak reflections are revealed on electron diffraction photographs for a phase, resulting in a tripling of the hexagonal latticec-dimension. These show to have a structure very similar to rhombohedral willemite (Zn₂SiO₄), with the (Mg, Al) metal atoms ordered with respect to the silicon atoms in a 21 ratio. However, there are some additional weak diffraction spots with indices not obeying the rhombohedral condition of –h+k+l=3n. It is proposed that the structure of this is identical to that of willemite and the extra spots are a result of some form of twinning, which implies the existence of ordered microdomains.     

Extraction of microamounts of Eu and Am into nitrobenzene using a synergistic mixture of chlorinated hydrogen dicarbollylcobaltate and <Emphasis Type="Italic">N,N′</Emphasis>-diethyl-<Emphasis Type="Italic">N,N′</Emphasis>-diphenyl-2,6-dipicolinamide

Extraction of microamounts of Eu and Am with a nitrobenzene solution of chlorinated hydrogen dicarbollylcobaltate (H⁺B⁻) in the presence of N,N′-diethyl-N,N′-diphenyl-2,6-dipicolinamide (EtPhDPA, L) was studied. The equilibrium data were interpreted assuming that the complexes HL⁺, HL₂⁺, ML₂³⁺, ML₃³⁺, and ML^4/3+ (M³⁺ = Eu³⁺, Am³⁺) are extracted into the organic phase. The extraction and stability constants of the species in water-saturated nitrobenzene were determined. The stability constants of the related complexes EuL _n ³⁺ and AmL _n ³⁺, where n = 2, 3, 4, in this medium are comparable.