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141.
Meeta Lavania Jyotsana Dalal Simrita Cheema Chandra Shekhar Nautiyal Banwari Lal 《European Food Research and Technology》2011,232(4):703-711
This study represents a comprehensive analysis and scientific validation of our ancient knowledge about the ethnopharmacological
aspects of cow urine by measuring the lipid peroxidation, radical scavenging, and level of reduced glutathione and catalase
activity. Graded doses of cow urine were administered orally to experimentally treated rats. Results of liver and plasma from
experimentally treated rats indicated that cow urine reduced the levels of thiobarbituric acid reactive substance significantly
in all the treatments (P < 0.01). In vitro experiments with the liver of control and experimentally treated rats were also carried out against cumene
hydroperoxide-induced lipid peroxidation. On LCMS analysis, the antioxidant component of cow urine was identified as uric
acid (m/z 169.07). The results demonstrate that the cow urine-mediated induction of antioxidant level controls oxidative damage,
even after minimal processing, and thus is indicative of its potential as a viable substitute of synthetic antioxidants. 相似文献
142.
143.
Md. Irshad Irfan Ahmad Syed Jafar Mehdi Harish Chandra Goel 《International Journal of Food Properties》2013,16(1):179-186
The antioxidant capacity of commonly consumed cucurbits vegetable was determined by the DPPH, FRAP, Fe3+ reducing power, and hydrogen peroxide scavenging assay. The aqueous extract of Luffa cylindrica showed the highest value of phenolic content and antioxidant capacity based on FRAP, Fe3+ reducing power, and hydrogen peroxide scavenging assay. However, Laginaria siceraria extract showed the highest flavonoid and DPPH scavenging activities among all three cucurbits used in this study. Phenolic content in aqueous extracts of Luffa cylindrica and Laginaria siceraria was almost equal. Cucurbita maxima exhibited the lowest phenolic, flavonoid content, and exhibited the lowest power of antioxidant scavenging. The antioxidant capacity of cucurbits was significantly correlated (P < 0.05) with the phenolic content of their extracts. The antioxidant capacity of Luffa cylindrica and Laginaria siceraria have also shown a significant correlation (P < 0.05). 相似文献
144.
R.J. Byron Smith L. MuruganandamS. Murthy Shekhar 《Computers & Chemical Engineering》2011,35(12):2646-2652
In the design of water gas shift reactors, the performance of catalysts is not known a priori and hence having a general kinetic expression will be of much help. Computational Fluid Dynamic study was carried out to investigate the performance of a packed bed reactor for different feed compositions using five commonly used types of macro kinetic models. User Defined Functions were developed for the reaction rate to predict the CO conversion in the reactor. The effects of temperature and time factor on CO conversion were studied. The Langmuir-Hinshelwood model gave the best prediction for H2 rich mixtures. The Temkin model was better for higher CO concentrations, whereas the other models gave large deviations for the fixed bed reactor. 相似文献
145.
Anant K. Singh Wentong Lu Dulal Senapati Sadia Afrin Khan Zhen Fan Tapas Senapati Teresa Demeritte Lule Beqa Paresh Chandra Ray 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(17):2517-2525
A recent gold nanotechnology‐driven approach opens up a new possibility for the destruction of cancer cells through photothermal therapy. Ultimately, photothermal therapy may enter into clinical therapy and, as a result, there is an urgent need for techniques to monitor the tumor response to therapy. Driven by this need, a nanoparticle surface‐energy‐transfer (NSET) approach to monitor the photothermal therapy process by measuring a simple fluorescence intensity change is reported. The fluorescence intensity change is due to the light‐controlled photothermal release of single‐stranded DNA/RNA via dehybridization during the therapy process. Time‐dependent results show that just by measuring the fluorescence intensity change, the photothermal therapy response during the therapy process can be monitored. The possible mechanism and operating principle of the NSET assay are discussed. Ultimately, this NSET assay could have enormous potential applications in rapid, on‐site monitoring of the photothermal therapy process, which is critical to providing effective treatment of cancer and multidrug‐resistant bacterial infections. 相似文献
146.
Shekhar Tyagi V. G. Sathe Gaurav Sharma Velaga Srihari Himanshu Kumar Poswal 《Journal of Materials Science》2018,53(10):7224-7232
In the earlier pressure-dependent Raman spectroscopic studies, it has been reported that BaTiO3 undergoes a tetragonal to cubic phase transition above ~ 2 GPa, whereas pressure-dependent X-ray absorption, X-ray diffuse scattering studies and pair distribution function studies have reported the presence of a low-symmetry rhombohedral phase above ~ 2.3 GPa. In this report, we present our pressure-dependent Raman spectroscopic studies on polycrystalline BaTiO3 which shows that it first undergoes a transition from tetragonal to orthorhombic/rhombohedral phase above ~ 2.6 GPa and then finally goes to the cubic phase above 8.4 GPa. Pressure-dependent synchrotron X-ray diffraction (SXRD) studies have also been carried out that provided rate of change of volume as a function of pressure resulting in bulk modulus of 215 ± 9 GPa. 相似文献
147.
Tapas Debnath Subrata Chandra Roy Claus H. Rüscher Altaf Hussain 《Journal of Materials Science》2009,44(1):179-185
Needle-shaped crystals of sizes up to 5 μm × 5 μm × 40 μm of nominal composition K
x
Nb
y
W1−y
O3 were synthesized by solid state method at 800 °C using appropriate amount of WO3, WO2, Nb2O5, and K2WO4. The samples were characterized with XRD, SEM, microprobe analysis, optical spectroscopy, and Raman spectroscopy. The XRD
patterns of the samples show single phase of tetragonal tungsten bronze (TTB) type (P4/mbm, No. 127) up to y = 0.07. Structure refinements reveal an increase in cell parameter with increasing nominal niobium content within the TTB
phase. The elemental compositions of the crystals determined by electron microprobe analysis also show an increase in Nb content
with increasing y. With increasing Nb content the reflectivity minimum in the near infrared spectral range shifts towards lower wavenumber
indicating the effect of decreasing carrier concentration. Pyrochlore type phase (KNbWO6) is obtained as a second phase when nominal composition y > 0.07. 相似文献
148.
Vehicular traffic control at road crossings has always been a matter of concern for administrations in many modern cities around the world. Several attempts have been made to design efficient automated systems to solve this problem. Most of the present day systems use predetermined timing circuits to operate traffic signals, which are not very efficient because they do not operate according to the current volume of traffic at the crossing. It is often seen in today's automated traffic control systems that vehicles have to wait at a road crossing even though there is little or no traffic in the other direction. There are other problems as well, such as ambulances getting caught up by a red traffic signal and wasting valuable time. Congestion is often translated into lost time, missed opportunities, lost worker productivity, delivery delay, and a general increased cost. 相似文献
149.
Calvert P Cesarano J Chandra H Denham H Kasichainula S Vaidyanathan R 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2002,360(1791):199-209
Toughness in hard biological tissues is associated with fibrous or lamellar structures that deflect or stop growing cracks. In some cases, such as nacreous shell, protein interlayers absorb much of the crack energy. In other tissues, such as tooth enamel, the toughness derives from the mineral microstructure, and the small amount of residual protein apparently has little effect. There have been a number of efforts to make tough synthetic materials using layered structures. In this work, freeform fabrication has been used to make layered structures with a view to introducing similar toughness into brittle materials. Results are presented for epoxy-glass composites with glass fabric interlayers, porous alumina back-filled with aluminium metal, and layered glass-ceramic/silver materials. 相似文献
150.
The conductivity of polymer gel electrolytes containing three aromatic and three aliphatic carboxylic acids has been studied, viz. (i) ortho-, meta- and para-hydroxybenzoic acids and (ii) oxalic, malonic and succinic acids. Polymeric gels were prepared by adding different wt% of polymer poly(methylmethacrylate) (PMMA) in solutions of respective acids in high dielectric constant organic solvent mixtures of propylene carbonate, ethylene carbonate and dimethylformamide. The highest conductivity in the first of the above group of acids is for o-hydroxy benzoic acid and oxalic acid in the second group of acids. Results have been explained on the basis of ortho and/or inductive effects which depend upon the relative positions of the substituted hydroxyl (–OH) and carboxyl (–COOH) group or that of the two carboxylic groups. 相似文献