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1

Mathematical modeling of first to third degree burn injury by sinusoidal heating source

100%

Rai K. N. , Srivastava V.

International Journal of Applied Mechanics and Engineering

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2009

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tom Vol. 14, no 2

489-500

EN

The object of this study is to provide a generalized mathematical model of burn injury due to a sinusoidal heat source at the skin surface. An application of double Fourier cosine transform is applied to convert this problem into a boundary value problem of ordinary differential equations. The solution thus obtained is transferred into a standard form with the help of the inverse discrete Fourier cosine transform. Finally, the numerical results obtained for the distribution of temperature in different layers of the skin during burn injury are discussed and displayed graphically.

2

Environmental perspectives of Vetiveria zizanioides (L.) Nash

80%

Srivastava J. , Kayastha S. , Jamil S. , Srivastava V.

Acta Physiologiae Plantarum

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2008

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tom 30

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nr 4

EN

The twentieth century witnessed indiscriminate usage of natural resources for energy generation and xenobiotic chemical compounds for sustainability in agriculture and infrastructural development. Heavy metal and non-degradable chemical contamination of soil and water is one of the major environmental threats. In recent years, worldwide researchers are concentrating on the exploration of various sustainable methods to mitigate such environmental contamination. Vetiver (Vetiveria zizanioides (L.) Nash), a grass, is a proven source to mitigate such pollution, and in present days is one of the most recent thrust areas for the purpose of environmental mitigation. Unique morphology, physiology and symbiotic association render vetiver capable of tolerating environmental extremities. In addition, vetiver is also helpful in degradation of most of the recalcitrant compounds such as benzo[a]pyrene. The present review reflects the environmental perspectives of vetiver grass, a potential field which led the World Bank to initiate vetiver grass technology (VGT), which is now known as vetiver system (VS), in India and most of the other Asian countries to restore the natural environmental conditions.

3

Economically viable synthesis of Fe3O4 nanoparticles and their characterization

80%

Srivastava V. , Singh P. K. , Weng C. H. , Sharma Y. C.

Polish Journal of Chemical Technology

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2011

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tom Vol. 13, nr 2

1-5

EN

Nano iron oxide particles (Fe3O4) were synthesized by coprecipitation of Fe2+ and Fe3+ by ammonia solution in the aqueous phase. Various instrumentation methods such as X ray Diffractometry (XRD), Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) and Vibrating Sample Magnetometery (VSM) were used to characterize the properties of nanoparticles. The size of the nanoparticles was measured and was found to be between 10 to 15 nm. The value of saturation magnetization of the nanoparticles was found to be 55.26 emu/g. The BET surface area of nano iron oxide particles measured to be 86.55 m2/g.

4

Simultaneous analysis of six bioactive lignans in Phyllanthus species by reversed phase hyphenated high performance liquid chromatographic technique

61%

Shanker K. , Singh M. , Srivastava V. , Verma R. K. , Gupta A. K. , Gupta M. M.

Acta Chromatographica

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2011

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tom Vol. 23, no. 2

321--337

EN

An online-hyphenated high-performance liquid chromatography-photodiode array-mass spectrometry (HPLC-PDA-MS) analytical method was developed for the simultaneous determination of six lignans of therapeutic importance in four Phyllanthus spp. (P. amarus, P. maderaspatensis, P. urinaria, and P. virgatus). HPLC with monolithic reverse phase silica column (4.6 × 100 mm) and simple isocratic elution of methanol-water mixed with dioxane facilitated the separation of lignans of diverse nature such as diarylbutyrolactone, tetrahydrofuran, isomeric aryltetralin, and diarylbutane type for quantitative analysis. Targeted lignans viz. heliobuphthalmin lactone (1), virgatusin (2), hypophyllanthin (3), phyllanthin (4), nirtetralin (5), and niranthin (6) were confirmed unambiguously in four Phyllanthus species by their abundant molecular adduct ions, retention time, UV, and mass spectra as compared with those of reference compounds. Advantages and limitations of both detection techniques for qualitative (fingerprinting) and quantitative analysis of the above mentioned lignans in four Phyllanthus spp. are discussed. The method was validated following international guidelines. The described method can be utilized for assays and stability tests of P. amarus extracts as well as traditional Indian medicine based on Phyllanthus herb.