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91.
Vidya Venkateswaran 《Algebras and Representation Theory》2016,19(2):473-487
We consider \(U_{q}(\mathfrak {gl}_{n})\), the quantum group of type A for |q| = 1, q generic. We provide formulas for signature characters of irreducible finite-dimensional highest weight modules and Verma modules. In both cases, the technique involves combinatorics of the Gelfand-Tsetlin bases. As an application, we obtain information about unitarity of finite-dimensional irreducible representations for arbitrary q: we classify the continuous spectrum of the unitarity locus. We also recover some known results in the classical limit \(q \rightarrow 1\) that were obtained by different means. Finally, we provide several explicit examples of signature characters. 相似文献
92.
Vidya B. Rana Mrs. Prabha Singh Dharam P. Singh Mahendra P. Teotia 《Transition Metal Chemistry》1982,7(3):174-177
Summary Trivalent chromium, manganese, iron and cobalt salts reactin situ with 2,6-diaminopyridine and acetylacetone to form complexes of the 16-membered N6 tetradentate macrocyclic ligand. The chelates are characterised as distorted square-pyramidal of [M(TML)X] type, where M = chromium(III), manganese(III), iron(III) and cobalt(III); X=Cl, Br, NO3 or NCS for chromium(III) and iron(III) and X=(OAc) for manganese(III) and (OH) for cobalt(III). The ligand coordinates through all the nitrogen atoms through deprotonation of two of them, however, the pyridine nitrogens do not take part in coordination. The chelates incorporate one anion or hydroxyl group in the coordination sphere. The magnetic, electronic and i.r. spectral studies indicate lower symmetries for these chelates. The amount of distortion is calculated in terms of DT/DQ by applying NSH theory. X-ray measurements on powder form of the complexes show their isomorphic nature and also support the proposed structures. 相似文献
93.
Wei Wei Rongxian Li Qinghang Liu Vidya Devanathadesikan Seshadri Vishnu Priya Veeraraghavan Krishna Mohan Surapaneni Thamaraiselvan Rengarajan 《Arabian Journal of Chemistry》2021,14(8):103238
BackgroundColorectal cancer (CRC) is a frequently diagnosed cancer that primarily affects the digestive system and an imperative cause of mortalities worldwide.ObjectiveIn this work, we formulated the Tin oxide-Sodium alginate-Polyethylene glycol-Allyl isothiocyanate nanocomposites (SAP-Ally-NCs) and investigated its anticancer role against the DMH-provoked CRC in rats.MethodologyThe formulated SAP-Ally-NCs were characterized different techniques. The CRC was provoked to the rats via injecting 20 mg/kg of DMH and then administered with the formulated SAP-Ally-NCs for 16 weeks. The bodyweight changes and the polyp’s incidences were detected and tabulated. The status of lipid peroxidation and antioxidant enzymes were studied by standard techniques. The inflammatory markers and xenobiotic enzymes level was scrutinized using respective kits. The mRNA expressions of various signaling molecules were examined by RT-PCR. The liver and colon tissues were examined microscopically to detect the histological changes.ResultsThe formulated SAP-Ally-NCs treatment appreciably improved the body weight gain and suppressed the polyp’s incidences in the DMH-challenged animals. SAP-Ally-NCs treated animals were demonstrated the notable reduction in the lipid peroxidation and inflammatory cytokines and elevated the antioxidant enzymes i.e. CAT and SOD activity. SAP-Ally-NCs administered animals exhibited the noticeable reduction in the expression of PCNA, cyclin-D1, iNOS, and COX-2 in the colon tissues. The histological findings also unveiled the therapeutic role of SAP-Ally-NCs.ConclusionIn conclusion, the SAP-Ally-NCs demonstrated the potent anticancer action against the DMH-provoked CRC in rats. In future, it could be a potent chemotherapeutic agent to the CRC. 相似文献
94.
Waghmare Ashish Sharma Vidhika Shinde Pratibha Punde Ashvini Vairale Priti Hase Yogesh Pandharkar Subhash Nair Shruthi Aher Rahul Doiphode Vidya Shah Shruti Rahane Swati Bade Bharat Prasad Mohit Rondiya Sachin Jadkar Sandesh 《Journal of Solid State Electrochemistry》2022,26(1):219-232
Journal of Solid State Electrochemistry - Indium selenide (γ-In2Se3) films were prepared using RF magnetron sputtering. Influence of deposition time on structural, optical, morphological, and... 相似文献
95.
A convenient and efficient one pot sequence has been developed for the transformation of alcohols to amines using Sodium azide, triphenylphosphine in CC14-DMF. 相似文献
96.
R. Vidya Sagar R. V. Prasad B. K. Raghu Prasad M. V. M. S. Rao 《Experimental Mechanics》2013,53(7):1161-1175
This article reports the acoustic emission (AE) study of precursory micro-cracking activity and fracture behaviour of quasi-brittle materials such as concrete and cement mortar. In the present study, notched three-point bend specimens (TPB) were tested under crack mouth opening displacement (CMOD) control at a rate of 0.0004 mm/sec and the accompanying AE were recorded using a 8 channel AE monitoring system. The various AE statistical parameters including AE event rate $ \left( {\frac{dn }{dt }} \right) $ , AE energy release rate $ \left( {\frac{dE }{dt }} \right) $ , amplitude distribution for computing the AE based b-value, cumulative energy (ΣE) and ring down count (RDC) were used for the analysis. The results show that the micro-cracks initiated and grew at an early stage in mortar in the pre peak regime. While in the case of concrete, the micro-crack growth occurred during the peak load regime. However, both concrete and mortar showed three distinct stages of micro-cracking activity, namely initiation, stable growth and nucleation prior to the final failure. The AE statistical behavior of each individual stage is dependent on the number and size distribution of micro-cracks. The results obtained in the laboratory are useful to understand the various stages of micro-cracking activity during the fracture process in quasi-brittle materials such as concrete & mortar and extend them for field applications. 相似文献
97.
Journal of Analytical Chemistry - We report a simple, visual detection strategy for cardiac biomarker, troponin I (cTnI), a promising indicator of cardiac disease based on heparin gold... 相似文献
98.
Peter D. Friedman Vidya D. Vadakoot William J. MeyerJr Steven Carey 《Experiments in fluids》2007,42(5):751-759
Experimental simulations were carried out to investigate the onset of instability in negatively buoyant fountains by injecting
glycerin–water mixtures into silicon oil. The transition from a stable to an unstable fountain structure is primarily governed
by the Richardson number, and to a lesser extent, Reynolds number, viscosity ratio, Weber number and vent geometry. Transition
nominally occurs at a Ri = 1.0. For a fountain issuing from a cylindrical pipe, the major effect of the Reynolds number is in determining whether
or not the fountain is laminar or turbulent. The Reynolds number effect can be largely accounted for by basing a corrected
Richardson number on the root mean square of the mean velocity. Viscosity ratio deviating from unity has the effect of stabilizing
the flow structure and thereby reducing the transition Richardson number. Similarly, interfacial tension stabilizes the flow
pattern resulting in a trend of increasing transition Richardson number with increasing Weber number. The results are valid
in rectangular vents if the Richardson number and Reynolds number are based on the hydraulic diameter. 相似文献
99.
Characterization and catalytic functionalities of copper oxide catalysts supported on zirconia 总被引:1,自引:0,他引:1
A series of zirconia supported copper oxide catalysts with varying copper loadings (1.2-19.1 wt %) were prepared by impregnation method. The catalysts were characterized by X-ray diffraction, UV-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), and temperature-programmed desorption of CO2. Copper dispersion and metal area were determined by N2O decomposition method. X-ray diffraction patterns indicate the presence of crystalline CuO phase beyond 2.7 wt % of Cu on zirconia. UV-visible diffuse reflectance spectra suggest the presence of two types of copper species on the ZrO2 support. XPS peaks intensity ratio of Cu 2p3/2 and Zr 3d5/2 was compared with Cu dispersion calculated from N2O decomposition. TPR patterns reveal the presence of highly dispersed copper oxide at lower temperatures and bulk CuO at higher temperatures. The basicity of the catalysts was found to increase with Cu loading, and the activity of the catalysts was also found to increase with the increase in Cu loading up to 2.7 wt % Cu loading. The catalytic properties were evaluated for the dehydrogenation of cyclohexanol to cyclohexanone and were related to surface properties of the copper species supported on zirconia. 相似文献
100.
Amreen Naz Shiva Arun Vidya Singh Shahid Suhail Narvi Mohammad Siraj Alam P.K. Dutta 《印度化学会志》2022,99(1):100296
An efficient silica-based inorganic-organic hybrid was synthesized by using 3-(2-aminoethylamino)propyltrimethoxylsilane as linker and 2-Quinolinecarboxaldehyde for Schiff's base formation which was further coordinated by Cu (II) chloride. The hybrid was characterized by relevant techniques, i.e., FT-IR, DRUV-Vis, SEM, EDX, ICP-AES, TGA and EPR technique which support its formation. The synthesized hybrid material was successfully used as heterogeneous catalyst for degrading Reactive Black-5 (RB-5), a non-biodegradable diazo dye. The degradation mechanism follows advanced oxidation technique utilizing hydrogen peroxide as an environmentally amiable green oxidant; where the hybrid catalyst decomposes H2O2 to generate ·OH free radicals. Effects of dye concentration, H2O2 concentration and temperature variation on dye degradation process were studied and best reaction conditions for maximum degradation of RB-5 were also worked out. The catalyst showed 87% dye degradation in 130 ?min at best reaction conditions. Easy separation, reusability and efficient dye degradation ability of the catalyst are the motivating factors for the development of such hybrid material for solving critical environmental issues. 相似文献