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排序方式: 共有256条查询结果,搜索用时 31 毫秒
161.
D.J.G. James A.C. Bajpai 《International Journal of Mathematical Education in Science & Technology》2013,44(2):331-336
The paper reviews the mathematical education of engineers in Portugal and Spain based on a short visit to four academic institutions. It highlights the need for greater mutual understanding of the issues, and closer collaboration between mathematics educators, if progress is to be made on establishing an agreed curriculum in mathematics for engineers throughout Europe. It is proposed that the Mathematics Working Group attached to the European Society for Engineering Education (SEFI) is an appropriate organization to develop such collaboration. 相似文献
162.
Khare P Gupta AK Gajula PK Sunkari KY Jaiswal AK Das S Bajpai P Chakraborty TK Dube A Saxena AK 《Journal of chemical information and modeling》2012,52(3):777-791
The present study describes a successful application of computational approaches to identify novel Leishmania donovani (Ld) AdoHcyase inhibitors utilizing the differences for Ld AdoHcyase NAD(+) binding between human and Ld parasite. The development and validation of the three-dimensional (3D) structures of Ld AdoHcyase using the L. major AdoHcyase as template has been carried out. At the same time, cloning of the Ld AdoHcyase gene from clinical strains, its overexpression and purification have been performed. Further, the model was used in combined docking and molecular dynamics studies to validate the binding site of NAD in Ld. The hierarchical structure based virtual screening followed by the synthesis of five active hits and enzyme inhibition assay has resulted in the identification of novel Ld AdoHcyase inhibitors. The most potent inhibitor, compound 5, may serve as a "lead" for developing more potent Ld AdoHcy hydrolase inhibitors as potential antileishmanial agents. 相似文献
163.
Kin Hong Liew Wan Zurina Samad Norazzizi Nordin Poh Lee Loh Joon Ching Juan Mohd Ambar Yarmo Badrul Hisham Yahaya Rahimi M. Yusop 《催化学报》2015,(5)
A new heterogeneous catalyst composed of Pd nanoparticles immobilized within a HypoGel resin has been prepared in the absence of any ligands using an extensive cross-linking method. This new-ly develop... 相似文献
164.
165.
Designing Swellable Beads of Alginate and Gelatin for Controlled Release of Pesticide (Cypermethrin)
In the present study biopolymeric beads of sodium alginate and gelatin were prepared by employing CaCl2 as a crosslinking agent. A series of such microspheres of different compositions were prepared by varying the amounts of sodium alginate, gelatin and CaCl2 in the feed mixture. The beads were loaded with an insecticide like cypermethrin. The prepared loaded and unloaded beads were characterized by FTIR spectral and Environmental scanning electron microscopy (ESEM) techniques, to gain insight into the molecular structure and morphology of beads, respectively. The swelling experiments were performed for different composition of beads and at varying pH and temperature of the swelling media. The swelling controlled release of insecticide was also investigated for 8 days in bi-distilled water as a release medium. The release experiments were performed under the static and varying experimental conditions and the data obtained were fitted to Fick's equation to evaluate diffusion coefficients of insecticide. The results were further analyzed by Fick's power law equation, and the possible mechanisms of the insecticide release were explored at different experimental conditions. Soil–pot experiments were also performed to demonstrate the applicability of the present controlled release technique to agricultural fields. 相似文献
166.
Novel electrically conducting and biocompatible composite hydrogel materials comprising of poly (aniline) (PANI) nanoparticles dispersed in a poly (vinyl alcohol) (PVA) – g–poly (acrylic acid) (PAA) matrix were prepared by in situ polymerization of aniline. The prepared ionic hydrogels were evaluated for their water uptake capacity in distilled water. While structural insights into the synthesized polymer was sought by Fourier Transform Infrared (FTIR) spectroscopy and X–Ray Diffraction (XRD) techniques, morphology and dimension of PANI particles embedded into the colored optically semi–transparent polymer films were evaluated by Scanning Electron Microscopy (SEM) analysis and Transmittance Electron Microscopy (TEM) while thermal behavior of composite hydrogel was investigated by Differential Scanning Calorimetry (DSC). Electrical conductivity of composite hydrogels containing different PANI percentage was determined by LCR. Considering the potential of electrically conductive nanocomposites materials in biomedical applications the in vitro blood compatibility of nanocomposites was investigated by employing several in vitro tests. 相似文献
167.
Ellis Bagga Sunita Kumari Rajesh Kumar Rakesh Kumar R. P. Bajpai Lalit M. Bharadwaj 《Pramana》2005,65(5):967-972
The present study reports the covalent immobilization of myosin on glass surface andin-vitro motility of actin-myosin biomolecular motor. Myosin was immobilized on poly-L-lysine coated glass using heterobifunctional
cross linker EDC and characterized by AFM. Thein-vitro motility of actin was carried out on the immobilized myosin. It was observed that velocity of actin over myosin increases
with increasing actin concentration (0.4–1.0 mg/ml) and was found in the range of 0.40–3.25 μm/s. The motility of actinmyosin
motor on artificial surfaces is of immense importance for developing nanodevices for healthcare and engineering applications 相似文献
168.
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170.
Sharayu Kasar S. Kumar Aishwarya Kar R. K. Bajpai C. P. Kaushik B. S. Tomar 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):71-75
The smectite-rich natural clay is being considered as a backfill and buffer material for Indian repository programme. In the present study, batch sorption measurements have been performed at trace concentrations for one of the minor actinide elements [Np(V)] and for the long lived fission products, Cs(I), Sr(II), and Tc(VII) on purified and conditioned smectite-rich clay at varying conditions of pH and ionic strength. In case of Cs(I) and Sr(II) the sorption was found to increase with pH. At any pH the sorption was found to decrease with increasing ionic strength of the suspension maintained with NaCl. Further, at any pH the sorption of Sr(II) is less than the corresponding value for Cs(I). This is indicative of effect of size selectivity on the sorption by the clay. Tc(VII), on the other hand, is poorly retained by the clay, which can be explained in terms of the negative charge on the TcO4 ? ion, which has negligible interaction with the predominantly negatively charged clay surface. In the case of Np(V), the sorption was found to increase albeit, slowly compared to Cs(I) and Sr(II) with pH, and it with no effect of ionic strength on the sorption at all pH values. This suggests that Np(V) primarily interacts with the surface sites via inner sphere complexation mechanism. 相似文献