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961.
Co(HMAT)2Cl and Co(HMAT)2 base H have been synthesized and characterized by elemental analyses, magnetic moments, electronic and infrared spectral
measurements. The results show them to be low spin octahedral in nature. Various parameters have been calculated using ligand
field theory of spin-allowed transitions.
The paper was presented at the Convention of Chemists, Bombay, December 1980. 相似文献
962.
Phosphorescence decay, thermoluminescence and electroluminescence of CaS : Ag phosphors prepared with a varying amount of silver as activator have been studied at room temperature, 301 K. The observations have been analysed to obtain the information about the type of kinetics involved in the luminescence process. In addition to this, the effect of the addition of an activator on the luminescence behaviour of the phosphors and on the distribution of trapping levels is discussed. 相似文献
963.
S. M. Kanetkar P. P. Patil S. V. Ghaisas S. B. Ogale V. G. Bhide 《Hyperfine Interactions》1988,41(1):587-590
The pulsed ruby laser induced reactive-quenching process at Fe/C6H6 Ibenzenel has been investigated using conversion electron Mössbauer spectroscopy [CEMS]. It is shown that iron carbide phases can be synthesized when an iron foil immersed in benzene is treated with ruby Laser pulses [λ=694 nm, pulse width ~30 ns, energy density =15 J/cm2]. The results indicate the formation of ε-carbide and Fe5C2 phases in the as-treated sample and its transformation to Fe3C upon thermal treatment. The result of the CEMS measurements are supported by small angle X-ray diffractometry. 相似文献
964.
A. Ramanujam N. M. Gudi M. N. Nadkarni S. K. Patil V. V. Ramakrishna 《Journal of Chemical Sciences》1982,91(4):347-350
Adduct formation between U(TTA)4 and neutral organosulphoxide donors dibenzyl sulphoxide (dbso), dimethyl sulphoxide (dmso), dihexyl sulphoxide (dhso) and
dioctylsulphoxide (doso) was studied by spectrophotometry. Each of these donors form a 1 : 1 adduct with U(TTA)4. The adduct formation constants (log βAB) were calculated from spectral changes and were found to be 3.10 (dbso), 3.23 (dmso), 3.62 (dhso) and 3.64 (doso). 相似文献
965.
Sandeep N. Patil Jayasinh S. Paradeshi Prapti B. Chaudhari Satyendra J. Mishra Bhushan L. Chaudhari 《Applied biochemistry and biotechnology》2016,180(4):638-654
In the present studies, renewable and nontoxic biopolymer, pectin, was extracted from Indian red pomelo fruit peels and used for the synthesis of cerium oxide nanoparticles (CeO2-NPs) having bio-therapeutic potential. The structural information of extracted pectin was investigated by FTIR and NMR spectroscopic techniques. Physicochemical characteristics of this pectin suggested its application in the synthesis of metal oxide nanoparticles. Using this pectin as a template, CeO2-NPs were synthesized by simple, one step and eco-friendly approach. The UV–Vis spectrum of synthesized CeO2-NPs exhibited a characteristic absorption peak at wavelength 345 nm, which can be assigned to its intrinsic band gap (3.59 eV) absorption. Photoluminescence measurements of CeO2-NPs revealed that the broad emission was composed of seven different bands. FTIR analysis ensured involvement of pectin in the formation and stabilization of CeO2-NPs. FT-Raman spectra showed a sharp Raman active mode peak at 461.8 cm?1 due to a symmetrical stretching mode of Ce–O vibration. DLS, FESEM, EDX, and XRD analysis showed that the CeO2-NPs prepared were polydispersed, spherical shaped with a cubic fluorite structure and average particle size ≤40 nm. These CeO2-NPs displayed broad spectrum antimicrobial activity, antioxidant potential, and non-cytotoxic nature. 相似文献
966.
Synthesis and Antimicrobial Activities of Novel 2‐[substituted‐1H‐pyrazol‐4‐yl] Benzothiazoles,Benzoxazoles, and Benzimidazoles
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Vikas S. Padalkar Bhushan N. Borse Vinod D. Gupta Kiran R. Phatangare Vikas S. Patil Nagaian Sekar 《Journal of heterocyclic chemistry》2016,53(5):1347-1355
In an endeavor to find a new class of antimicrobial agents, a series of novel substituted benzimidazole, benzoxazole, and benzothiazole derivatives 6 containing pyrazole moiety have been synthesized by reaction of 3‐aryl‐4‐formyl pyrazole 4 with substituted phenylenediamine or o‐aminophenol or o‐aminothiophenol 5 . Reaction of phenyl hydrazine or 2‐hydrazinopyridine 1 with substituted acetophenones 2 gave the corresponding hydrazones 3 , which on Vilsmeier–Haack reaction with POCl3–DMF gave substituted 3‐aryl‐4‐formyl pyrazoles 4 . All final compounds 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k were evaluated for in vitro antibacterial activities against Escherichia coli and Staphylococcus aureus strains and in vitro antifungal activity against Candida albicans and Aspergillus niger strains by using serial dilution method. The antimicrobial activities were expressed as the minimum inhibitory concentration in µg/mL. The compound containing benzimidazole and benzoxazole moiety gave better antibacterial and antifungal activities than benzothiazole compounds. 相似文献
967.
Sudam S. Pandule Suresh U. Shisodia Mahadeo R. Patil Rajendra P. Pawar Vasant V. Chabukswar 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(12):768-772
The poly(2-chloroaniline) was prepared by in situ chemical oxidative polymerization method using ammonium thiosulphate as an oxidant and methanesulfonic acid as a dopant. The optical absorption spectra showed bands for π-π* transition of the benzenoid ring at 265 nm and at 350 nm for n-π* transition of the quinonoid ring. The broad band appeared around 550 nm was due to transition of electrons from the valance band to the conduction band, this also confirmed the good electrical conductivity of the polymer. The X-ray diffraction pattern showed characteristic diffraction peak at 2θ = 26° confirming a emeraldine salt form of the poly(2-chloroaniline). The electrical conductivity of the polymer measured by the two probe method at room temperature was 2.21×10?3 S/cm, which was found to be thermally activated. The linear increase in conductivity with increase in the temperature suggested the electron hopping mechanism. The methanesulfonic acid doped poly(2-chloroaniline) presents a linear dependency of its electrical resistance with an increase in ammonia gas concentration (1 ppm to 300 ppm) and creates a promising sensing material for ammonia gas sensing applications. 相似文献
968.
A One‐Pot Chemically Cleavable Bis‐Linker Tether Strategy for the Synthesis of Heterodimeric Peptides
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Nitin A. Patil Dr. Julien Tailhades Dr. John A. Karas Prof. Frances Separovic Prof. John D. Wade Dr. Mohammed Akhter Hossain 《Angewandte Chemie (International ed. in English)》2016,55(47):14552-14556
Heterodimeric peptides linked by disulfide bonds are attractive drug targets. However, their chemical assembly can be tedious, time‐consuming, and low yielding. Inspired by the cellular synthesis of pro‐insulin in which the two constituent peptide chains are expressed as a single‐chain precursor separated by a connecting C‐peptide, we have developed a novel chemically cleavable bis‐linker tether which allows the convenient assembly of two peptide chains as a single “pro”‐peptide on the same solid support. Following the peptide cleavage and post‐synthetic modifications, this bis‐linker tether can be removed in one‐step by chemical means. This method was used to synthesize a drug delivery‐cargo conjugate, TAT‐PKCi peptide, and a two‐disulfide bridged heterodimeric peptide, thionin (7‐19)‐(24‐32R), a thionin analogue. To our knowledge, this is the first report of a one‐pot chemically cleavable bis‐linker strategy for the facile synthesis of cross‐bridged two‐chain peptides. 相似文献
969.
Total Chemical Synthesis of an Intra‐A‐Chain Cystathionine Human Insulin Analogue with Enhanced Thermal Stability
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Dr. John A. Karas Nitin A. Patil Dr. Julien Tailhades Dr. Marc‐Antoine Sani Dr. Denis B. Scanlon Prof. Briony E. Forbes Dr. James Gardiner Prof. Frances Separovic Prof. John D. Wade Dr. Mohammed Akhter Hossain 《Angewandte Chemie (International ed. in English)》2016,55(47):14743-14747
Despite recent advances in the treatment of diabetes mellitus, storage of insulin formulations at 4 °C is still necessary to minimize chemical degradation. This is problematic in tropical regions where reliable refrigeration is not ubiquitous. Some degradation byproducts are caused by disulfide shuffling of cystine that leads to covalently bonded oligomers. Consequently we examined the utility of the non‐reducible cystine isostere, cystathionine, within the A‐chain. Reported herein is an efficient method for forming this mimic using simple monomeric building blocks. The intra‐A‐chain cystathionine insulin analogue was obtained in good overall yield, chemically characterized and demonstrated to possess native binding affinity for the insulin receptor isoform B. It was also shown to possess significantly enhanced thermal stability indicating potential application to next‐generation insulin analogues. 相似文献
970.
S. F. Patil Nilima S. Rajurkar A. T. Thakare 《Journal of Radioanalytical and Nuclear Chemistry》1987,108(3):149-157
The effect of some alkali metal chlorides on obstruction effect // and activation energy /E/ for the tracer-diffusion of cobalt ions is studied in agar gel medium using the zone-diffusion technique. It is observed that both the parameters, and E, decrease with increasing charge density of cation of the supporting electrolyte. This trend is explained on the basis of competitive hydration between ions and agar molecules and the relative distortion in the water structure brought about by these different ions and agar molecules, respectively. 相似文献