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1.
Kumari Asha Neeraj Kumar Biswas Sakshi Saxena Vibha Rani Satsangi Rohit Shrivastav Rama Kant Sahab Dass 《International Journal of Hydrogen Energy》2021,46(40):20858-20870
The present study attempts quantitative determination of changes in the morphological surface features viz. fractal dimension, lower and upper cut off length scale through Power Spectral Density analysis prior to and after irradiation of 100 KeV Ar+ ion beam at incidence angles of 0°, 40° and 60° on ZnO thin films. All the unirradiated and irradiated samples are subjected to photoelectrochemical characterization and a correlation between photoelectrochemical performance and morphological parameters is established. Sample irradiated at 40° angle at the fluence of 5 × 1016 ions/cm2 is found to possess maximum fractal dimension of 2.72, lower and upper cut off length scale of 3.16 nm and 63.00 nm respectively. This sample exhibits maximum photocurrent density of 3.19 mA/cm2 and applied bias photon-to-current efficiency of 1.12% at 1.23 V/RHE. Hydrogen gas collected for duration of 1 h for the same sample was ~4.83 mLcm?2. 相似文献
2.
Walia Gurjit Singh Kumar Ashish Saxena Astitwa Sharma Kapil Singh Kuldeep 《Pattern Analysis & Applications》2020,23(3):1439-1455
Pattern Analysis and Applications - Particle filter is used extensively for estimation of target nonlinear and non-Gaussian state. However, its performance suffers due to its inherent problem of... 相似文献
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4.
Nina Kubatova Dr. Hendrik R. A. Jonker Dr. Krishna Saxena Dr. Christian Richter Verena Vogel Sandra Schreiber Prof. Dr. Anita Marchfelder Prof. Dr. Harald Schwalbe 《Chembiochem : a European journal of chemical biology》2020,21(1-2):149-156
Past sequencing campaigns overlooked small proteins as they seemed to be irrelevant due to their small size. However, their occurrence is widespread, and there is growing evidence that these small proteins are in fact functionally very important in organisms found in all kingdoms of life. Within a global proteome analysis for small proteins of the archaeal model organism Haloferax volcanii, the HVO_2922 protein has been identified. It is differentially expressed in response to changes in iron and salt concentrations, thus suggesting that its expression is stress-regulated. The protein is conserved among Haloarchaea and contains an uncharacterized domain of unknown function (DUF1508, UPF0339 family protein). We elucidated the NMR solution structure, which shows that the isolated protein forms a symmetrical dimer. The dimerization is found to be concentration-dependent and essential for protein stability and most likely for its functionality, as mutagenesis at the dimer interface leads to a decrease in stability and protein aggregation. 相似文献
5.
Mrinal Kanti Kundu Goutam Hatui Vineeta Nigam Arvind Kumar Saxena 《Polymer-Plastics Technology and Engineering》2015,54(7):691-702
A tubelike, naturally occurring halloysite clay mineral (HNTs) incorporated polyphosphazene (PPZ) elastomeric nanocomposites had been electron beam radiated and thermally treated for certain applications. To improve the dispersion of raw HNTs (H), an organosilane modifier had been exploited. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) technique were utilized for plausible interaction and intercalation. The efficiency of electron beam radiation over chemical initiation for intra and inter chain network formation within the resin was substantiated through oil and solvent resistance studies. Effective delay in mass transport as compared to the virgin elastomer was observed through thermal analysis. 相似文献
6.
Structure‐Guided Design of Thiazolidine Derivatives as Mycobacterium tuberculosis Pantothenate Synthetase Inhibitors 下载免费PDF全文
Parthiban Brindha Devi Ganesh Samala Jonnalagadda Padma Sridevi Shalini Saxena Mallika Alvala Elena G. Salina Prof. Dharmarajan Sriram Prof. Perumal Yogeeswari 《ChemMedChem》2014,9(11):2538-2547
The pantothenate biosynthetic pathway is essential for the persistent growth and virulence of Mycobacterium tuberculosis (Mtb) and one of the enzymes in the pathway, pantothenate synthetase (PS, EC: 6.3.2.1), encoded by the panC gene, has become an appropriate target for new therapeutics to treat tuberculosis. Herein, we report nanomolar thiazolidine inhibitors of Mtb PS developed by a rational inhibitor design approach. The thiazolidine compounds were discovered by using energy‐based pharmacophore modelling and subsequent in vitro screening, which resulted in compounds with a half maximal inhibitory concentration (IC50) value of (1.12±0.12) μM . These compounds were subsequently optimised by a combination of modelling and synthetic chemistry. Hit expansion of the lead by chemical synthesis led to an improved inhibitor with an IC50 value of 350 nM and an Mtb minimum inhibitory concentration (MIC) of 1.55 μM . Some of these compounds also showed good activity against dormant Mtb cells. 相似文献
7.
A few aluminum containing polycarbosilanes named AlOR-PCS and Alac-PCS have been synthesized by the reaction of aluminum isopropoxide (AlOR) and aluminum acetylacetonate (Alac) with polycarbosilane (PCS), respectively. These materials were characterized by Fourier Transform Spectroscopy (FTIR), Thermo gravimetric Analysis (TGA) and Gel Permeation Chromatography (GPC). The rheological properties of these compounds were studied with respect to time, temperature and atmosphere (inert & air). It has been observed that the increase in metal content enhances the crosslinking of the PCS chains. Under similar conditions, the crosslinking of AlOR-PCS derivatives was found slower than Alac-PCS. GPC analysis of the samples showed the increase in molecular weight of these compounds compared to virgin PCS. TGA showed improved ceramic yield with increasing metal content. Alac-PCS gave higher ceramic yield than AlOR-PCS for similar molar ratios of metal complexes. 相似文献
8.
Rajesh Kumar Gayatri Sahu Shailendra K. Saxena Hari M. Rai Pankaj R. Sagdeo 《SILICON》2014,6(2):117-121
A qualitative evolution of an asymmetric Raman line-shape function from a Lorentzian line-shape is discussed here for application in low dimensional semiconductors. The step-by-step evolution reported here is based on the phonon confinement model which is successfully used in literature to explain the asymmetric Raman line-shape from semiconductor nanostructures. Physical significance of different terms in the theoretical asymmetric Raman line-shape has been explained here. Better understanding of theoretical reasoning behind each term allows one to use the theoretical Raman line-shape without going into the details of theory from first principle. This will enable one to empirically derive a theoretical Raman line-shape function for any material if information about its phonon dispersion relation, size dependence, etc., is known. 相似文献
9.
Komal Saxena 《Integrated ferroelectrics》2017,184(1):50-54
ABSTRACTThis paper presents simulation studies and theoretical analysis of sensing property of concentric square ring metamaterial biological materials. Phantom of dielectric cell having dimension 100 µm long and 25 µm in radius is considered. Sensor is designed using periodic arrays of split ring resonators and wires having negative permittivity and permeability at 16.694 GHz. Transmission parameters are extracted using CST MWS software. Change in resonance is observed on placing phantom close to the sensor due to the change in capacitance and inductance. Designed sensor can sense single phantom cell with 133 MHz of shift in resonance. Study shows that sensor has good sensitivity for detecting micron size dielectric objects. 相似文献
10.
Hydrogen peroxide sensing properties of PVA/TiO2/I2 nanocomposite‐based free standing membranes 下载免费PDF全文
The nanocomposite of titanium‐di‐oxide (TiO2)/iodine (I2) in polyvinyl alcohol (PVA) matrix has been explored to be used in hydrogen peroxide (H2O2) sensing applications for the first time. The proposed nanocomposite can be easily casted in the form of thin film on glass substrates as well as free standing membranes. These nanocomposite films and membranes exhibit reduced resistance values and easily observable colour changes in the presence of H2O2. The films also exhibit significant quenching in photoluminescence emission properties upon H2O2 exposure. These sensor responses have been attributed to redox reactions at nanocomposite films and H2O2 interface. This study indicates an easy to fabricate, flexible and environmental friendly sensing platform for H2O2. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42257. 相似文献