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11.
Sunil U. Tekale Suresh S. Shisodia Sushma S. Kauthale Vivekanand B. Jadhav Nilesh S. Kanhe Sudha V. Bhoraskar 《合成通讯》2013,43(13):1849-1858
The present work introduces for the first time the catalytic utility of micron particulate aluminium nitride (AlN/Al) as a novel and reusable heterogeneous catalyst for the synthesis of bis(indolyl)methanes involving the electrophilic substitution of indoles on aldehydes. The catalyst is recyclable and works without any significant change in its catalytic activity. 相似文献
12.
Zahra Afrasiabi Rosana Almudhafar Di Xiao Ekkehard Sinn Amitava Choudhury Aamir Ahmad Alok Vyas Fazlul Sarkar Subhash Padhye 《Transition Metal Chemistry》2013,38(6):665-673
A planar, polycyclic and aromatic hydrocarbon ligand, namely 9,10-phenanthrenequinone semicarbazone, and its transition metal complexes have been synthesized and structurally characterized. The in vitro antiproliferative activity of these compounds against five human cancer cell lines revealed that they were effective against androgen receptor-positive/negative prostate cancer cells as well as COX-positive pancreatic BxPC-3 cancer cell line. The driving force behind such antiproliferative activity seems to be the up-regulated COX expression in these cells, which was amenable for targeting through metal complexation. These structural motifs can, therefore, serve as a starting point for developing novel cytotoxic agents against the growing number of prostate and pancreatic cancers. 相似文献
13.
14.
Vijayakumar Uppar Sandeep Chandrashekharappa Chandan Shivamallu Sushma P Shiva Prasad Kollur Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Atiyaparveen I. Basarikatti Mallikarjun Chougala Mrudula Mohan M Govindappa Banuprakash Jayadev Katharigatta N. Venugopala Belakatte P. Nandeshwarappa Ravindra Veerapur Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Kiran K. Mudnakudu-Nagaraju Basavaraj Padmashali Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2021,26(9)
15.
This article discusses the effect of increasing mass percentage of nanoclay on the thermal, structural and morphological properties of nanoclay/nylon-6 nanocomposite. Polymerization of ε-caprolactam conducted in the presence of clay resulted in increased d-spacing and expansion of the clay galleries. A combination of differential scanning calorimetry, X-ray diffraction and electron microscopy was used to study the structure–property relationship. The effect of clay on the melting behavior of nylon-6 was studied by using quenched and normally cooled samples. The clay particles acted as external nucleating agents, and a dramatic effect on the crystallization behavior of nylon-6 was observed. The nylon-6 crystals formed are predominantly of the γ-type in the presence of clay. The presence of up to 1 % of clay lead to an increase in the heat of fusion. For nylon-6 samples containing greater than 1 % clay, the heat of fusion decreased significantly. 相似文献
16.
New dislocation etchants for anhydrous diglycine sulfate single crystals have been developed and the etching results are reported. Dichloroacetic acid, glacitel acetic acid and their mixtures work as dislocation etchants on the cleavage plane of the crystal. Morphology of the etch pits was found to vary with the etchant composition. 相似文献
17.
The effect of various growth parameters; seed morphology, growth-temperature and pH of the mother solution on the growth of TGS single crystals is studied. The effect of these variables on the crystal morphology and perfection is reported. It is shown that; (i) The crystal quality is much dependent on the seed and the growth temperature and (ii) the pH-control is a simple and an effective method for obtaining TGS crystals of required morphology. 相似文献
18.
The growth of single crystals of lanthanum heptamolybdate is achieved by allowing controlled diffusion of La ions through silica gel using the system La(NO3)3 MoO3 NH4OH HNO3–Na2SiO3. The reaction mechanism leading to the growth is reported. Mechanism of crystallization of La heptamolybdate is discussed. Formation of Liesegang rings consisting of La heptamolybdate crystals in the system is reported. It is observed that concentration programming and seeded growth enhances the size of crystals. The crystals grown in the system are single crystal platelets exhibiting squarish or octagonal facets. Some crystals exhibit a spherulitic morphology. 相似文献
19.
Dielectric characteristics of neodymium heptamolybdate crystals grown by gel encapsulation technique
Sushma Bhat S. K. Khosa Dr. P. N. Kotru R. P. Tandon 《Crystal Research and Technology》1995,30(2):267-273
Results obtained from the dielectric studies of neodymium heptamolybdate crystals grown in the system Nd(NO3)3 –MoO3 –NH4OH– HNO3 —Na2SiO3 by gel encapsulation technique are presented. The variation of dielectric constant (ε′), dielectric loss (tanδ) and conductivity (σ) with frequency at different temperatures is studied. The dielectric constant of the material increases sharply, attains a peak value and then decreases rapidly, as material's temperature rises from room temperature to higher degrees. The temperature at which the peak value is attained is the transition temperature of the material. Dielectric loss (tan δ) follows almost a similar behaviour. The conductivity (σ) is also found to be temperature-and frequency-dependent. This sharp rise in ε′ is attributed to the contribution from space charge polarization. Theoretically obtained data using the expression ε′ = a0 + a1 T2 and —In σ = a + b(T — T0)2 for T < T0) fits very well with the experimentally obtained data indicating that space charge polarization increases as some power of temperature larger than one. 相似文献
20.
A tensile testing machine suitable for optical fibre and optical cable testing is described. This machine uses specially developed gripping arrangements to obviate damage to the sample during testing. Some preliminary measurements of the stress/strain behaviour of coated fibres and optical cables are presented. 相似文献