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991.
C. Ramachandran T.N. Shanmugam H.M. Srivastava A. Swaminathan 《Applied mathematics and computation》2007,190(2):1627-1636
The main purpose of this paper is to introduce a new class of functions which are analytic in the open unit disk . We obtain various results including characterization, coefficient estimates, and distortion and covering theorems, for functions belonging to the class . 相似文献
992.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
993.
Inside Cover: Torands Revisited: Metal Sequestration and Self‐Assembly of Cyclo‐2,9‐tris‐1,10‐phenanthroline Hexaaza Macrocycles (Chem. Eur. J. 23/2015)
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994.
Enhanced Lithium‐Ion Storage Capability of a Bismuth Sulfide/Graphene Oxide/Poly(3,4‐ethylenedioxythiophene) Composite
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Radha Mukkabla Dr. Melepurath Deepa Dr. Avanish Kumar Srivastava 《Chemphyschem》2015,16(15):3242-3253
A Bi2S3/graphene oxide (GO) composite enwrapped by a poly(3,4‐ethylenedioxythiophene) (PEDOT) coating was prepared for the first time for use as an anode in Li‐ion batteries. Pristine Bi2S3 nanoflowers and composites of Bi2S3/GO and Bi2S3/GO/PEDOT were assembled into half cells with Li metal as the counter electrode, and initial discharge capacities of 833, 1020, and 1300 mAh g?1, respectively, were obtained. Composites of Bi2S3/GO/PEDOT and Bi2S3/GO showed superior cycling stability and better rate capability than pristine Bi2S3. GO provides highly conducting interconnections, which allow facile propagation of electrons during charge/discharge, and this improves the ion‐uptake capability of the Bi2S3 nanoflowers and also increases the rate capability. PEDOT furnishes a protective coating that prevents detachment of the material from the current collector during cycling, and it also imparts better cycling stability to the Bi2S3/GO/PEDOT composite. 相似文献
995.
V?D?Sirisha?Gandreddi Vijaya?Rachel?KappalaEmail author Kunal?Zaveri Kiranmayi?Patnala 《BMC biochemistry》2015,16(1):23
Background
The defensive capacities of plant protease Inhibitors (PI) rely on inhibition of proteases in insect guts or those secreted by microorganisms; and also prevent uncontrolled proteolysis and offer protection against proteolytic enzymes of pathogens.Methods
An array of chromatographic techniques were employed for purification, homogeneity was assessed by electrophoresis. Specificity, Ki value, nature of inhibition, complex formation was carried out by standard protocols. Action of SNTI on insect gut proteases was computationally evaluated by modeling the proteins by threading and docking studies by piper using Schrodinger tools.Results
We have isolated and purified Soap Nut Trypsin Inhibitor (SNTI) by acetone fractionation, ammonium sulphate precipitation, ion exchange and gel permeation chromatography. The purified inhibitor was homogeneous by both gel filtration and polyacrylamide gel electrophoresis (PAGE). SNTI exhibited a molecular weight of 29 kDa on SDS-PAGE, gel filtration and was negative to Periodic Acid Schiff’s stain. SNTI inhibited trypsin and pronase of serine class. SNTI demonstrated non-competitive inhibition with a Ki value of 0.75?±?0.05×10-10 M. The monoheaded inhibitor formed a stable complex in 1:1 molar ratio. Action of SNTI was computationally evaluated on larval gut proteases from Helicoverpa armigera and Spodoptera frugiperda. SNTI and larval gut proteases were modeled and docked using Schrodinger software. Docking studies revealed strong hydrogen bond interactions between Lys10 and Pro71, Lys299 and Met80 and Van Der Waals interactions between Leu11 and Cys76amino acid residues of SNTI and protease from H. Armigera. Strong hydrogen bonds were observed between SNTI and protease of S. frugiperda at positions Thr79 and Arg80, Asp90 and Gly73, Asp2 and Gly160 respectively.Conclusion
We conclude that SNTI potentially inhibits larval gut proteases of insects and the kinetics exhibited by the protease inhibitor further substantiates its efficacy against serine proteases.996.
Pone Kamdem Boniface Manju Singh Surjeet Verma Aparna Shukla Feroz Khan Santosh Kumar Srivastava 《Natural product research》2015,29(7):676-680
A simple and reliable high-performance liquid chromatographic method was successfully developed for the study of fingerprint chromatograms of extract and fractions from the leaves of Spathodea campanulata (SC) using verminoside (1) and 1-O-(E)-caffeoyl-β-gentiobiose (2) as marker compounds. Antioxidant activity of SC was determined by using free radical of 2,2-diphenyl-1-picryl-hydrazyl-hydrate as an experimental model. The docking study of selected target, tyrosinase and ligands (ascorbic acid, compounds 1 and 2) was performed through Autodock Vina v0.8. Fingerprints of methanol, chloroform, ethylacetate, n-butanol and water extracts could resolve 13, 11, 22, 16 and 5 peaks, respectively. Extract, fractions and compounds 1 and 2 previously isolated from SC displayed remarkable antioxidant activity with radical-scavenging activity ranging from 2.5 to 6.7 μg/mL. In silico study identified compounds 1 and 2 as potential inhibitors of tyrosinase correlating with the observed antioxidant activity in vitro. 相似文献
997.
A novel acidic ionic liquid–catalyzed protocol for the synthesis of diversely substituted tetracyclic indole core has been devised. The application of ionic liquid provides this methodology with various merits over conventional methods regarding reaction time, yield, and ease of handling. Acidic ionic liquid has been employed as a catalytic agent in this protocol. 相似文献
998.
S. S. Das B. P. Baranwal S. A. Rayeeny Punita Singh Vibha Srivastava 《Progress in Crystal Growth and Characterization of Materials》2002,44(3):155-161
A number of samples of glassy sodium polyphosphate and copolyphosphates of sodium — cobalt, sodium — copper, sodium — nickel, sodium-manganese and sodium — calcium were prepared and their optical properties were investigated. The ultraviolet and visible spectra of these glasses were recorded at the room temperature. It was found that the fundamental absorption edge of these glasses usually occurs in the ultraviolet — visible region. The optical absorption edges (E0) were calculated by using the relation h ν = B (hν − E0)2 where B is constant. The linear variation of (hν)1/2 with hν where is the absorption coefficient and hν is the incident photon energy, is taken as evidence of non-direct interband transitions. The E0 values obtained for copolyphosphate glasses appeared to depend on the size of the counter cation. The infrared spectra of all these glasses appeared to be almost the same, indicating the presence of characteristic P --- O --- P linkages of linear polyphosphate chains and two non bridging oxygen atoms bonded to phosphorus atoms O --- P --- O (PO2) units in the polyphosphate tetrahedra. 相似文献
999.
In order to protect the life of all creatures living in the environment, the toxicity arising from various hazardous chemicals must be controlled. This imposes a serious responsibility on different chemical, pharmaceutical, and other biological industries to produce less harmful chemicals. Among various international initiatives on harmful aspects of chemicals, the ‘Green Chemistry’ ideology appears to be one of the most highlighted concepts that focus on the use of eco-friendly chemicals. Ionic liquids are a comparatively new addition to the huge garrison of chemical compounds released from the industry. Extensive research on ionic liquids in the past decade has shown them to be highly useful chemicals with a good degree of thermal and chemical stability, appreciable task specificity and minimal environmental release resulting in a notion of ‘green chemical’. However, studies have also shown that ionic liquids are not intrinsically non-toxic agents and can pose severe degree of toxicity as well as the risk of bioaccumulation depending upon their structural components. Moreover, ionic liquids possess issues of waste generation during synthesis as well as separation problems. Predictive quantitative structure–activity relationship (QSAR) models constitute a rational opportunity to explore the structural attributes of ionic liquids towards various physicochemical and toxicological endpoints and thereby leading to the design of environmentally more benevolent analogues with higher process selectivity. Such studies on ionic liquids have been less extensive compared to other industrial chemicals. The present review attempts to summarize different QSAR studies performed on these chemicals and also highlights the safety, health and environmental issues along with the application specificity on the dogma of ‘green chemistry’. 相似文献
1000.
The energetics and structural, electronic and optical absorption properties of thallium nanowires, Tl n with n?=?1–18, have been investigated by employing a first-principles density functional theory in the local density approximation. The spin–orbit (SO) interaction has also been considered. We study four types of stable structures: planar, caged, pyramidal and helical. In general, the binding energy increases with the coordination number except in a few cases where the nearest-neighbours lie at comparatively larger separations. The maximum stability is seen for the helical configurations containing pentagons, hexagons, heptagons and octagons. Nanowires containing a core linear chain of atoms on the tube axis are more stable than the corresponding nanotubes having no such chains. All the wires or tubes are found to be metallic with or without consideration of the SO interaction. The electronic structures of the pentagonal-, hexagonal- and octagonal-configuration wires provide a large number of channels, which may give rise to large quantum ballistic conduction. One finds large differences between the optical absorption calculated with and without the SO interaction. Consideration of the SO interaction enhances the number of absorption peaks by approximately a factor of two. A strong and multi-peaked optical absorption, extending up to 4.0?eV including the visible region, appears for wires containing pentagons and octagons. These wires may thus be useful as a source of white radiation. 相似文献