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101.
102.
Yadav  Anuradha  Chakraverty  Shampa  Sibal  Ritu 《World Wide Web》2019,22(4):1499-1521
World Wide Web - There is no single universally agreed definition of trust for online systems. This has resulted in various trust metrics being proposed by researchers with diverse methods of...  相似文献   
103.
This paper reports the liquefied petroleum gas (LPG) sensing of titanium dioxide (Qualigens, India). Scanning electron micrographs and X-ray diffraction studies of samples were done. SEM shows that the material is porous and has grapes-like morphology before exposure to the LPG. XRD patterns reveal the crystalline nature of the material. The crystallites sizes of the TiO2 were found in the range of 30–75 nm. Variations in resistance with exposure of LPG to the sensing element were observed. The average sensitivity for different volume percentages of gas was estimated. The maximum value of average sensitivity was 1·7 for higher vol.% of LPG. Percentage sensor response (%SR) as a function of time was calculated and its maximum value was 45%. Response time of the sensor was 70 s. The sensor was quite sensitive to LPG and results were found reproducible.  相似文献   
104.
The Journal of Supercomputing - In this paper we demonstrate how to solve the chromatic sum problem using a D-Wave quantum computer. Starting from a BIP (binary integer programming) formulation, we...  相似文献   
105.
This study exposes enhanced hydrogen evolution capability of Mg doped Calcium ferrite nanocomposite without any co-catalysts under natural sunlight irradiation. Structural studies of this chemically (sol-gel) synthesised nanocomposite revealed the co-existence of two or three complex oxide ferrites along with iron oxide phases. Optical studies confirmed its narrower bandgap suitable for visible light absorbance. Elemental analysis shows the presence and oxidation state of elements in all undoped and doped calcium ferrite photocatalysts. Hydrogen evolution rate of undoped and Mg doped Calcium ferrite calcined at three different temperatures is discussed. It was found that doping of Mg in calcium ferrite resulted in 19.6 times higher hydrogen evolution ratethan undoped calcium ferritedue to the co-operative assistance of each individual phase present in the nanocomposite.  相似文献   
106.
This paper presents a study on thickness dependent physical properties of cadmium selenide thin films. The films of thickness 445, 631 and 810 nm were deposited employing thermal evaporation technique on glass and ITO-coated glass substrates followed by thermal annealing in air atmosphere at 200 °C. These films were subjected to X-ray diffractometer, UV–Vis spectrophotometer, scanning electron microscopy(SEM) and electrometer for structural, optical,surface morphological and electrical analysis respectively. The structural analysis reveals that the films are nanocrystalline in nature with cubic phase and preferred orientation(111). The crystallographic parameters such as lattice constant, interplanar spacing, grain size, internal strain, dislocation density, number of crystallites per unit area and texture coefficient are calculated and discussed. The optical band gap is found in the range 1.75–1.92 e V and observed to increase with thickness.The SEM study shows that the annealed films are uniform, fully covered and well defined. The electrical analysis shows that the conductivity is varied with film thickness and found within the order of semiconductor behavior.  相似文献   
107.
A new Schiff base functionalized dicyanate ester was synthesized and the monomer was characterized by FTIR, 1H-NMR, 13C-NMR and elemental analysis techniques. This prepared dicyanate ester with catalyst was then blended with BMI resin at different ratios by solution technique. The composites were made by impregnating the fibers with the blend solution followed by curing at various time-temperature schedules. The mechanical properties of the blend composites were tested. The fiber volume fraction of the composites were found to be in the range 41 ± 3%. The mechanical properties such as tensile modulus (32–35 GPa), flexural modulus (56–59 GPa) and Mode I fracture toughness (GIC = 104–136 J/m2) and impact response (1,121–1,218 J/m) were found to increase with increasing cyanate ester content in the Cy/BMI blends. From the DMA study it was observed that as the cyanate content increases from 3 to 9% in the blend the tan δ value increases from 0.112 to 0.126 and the storage modulus decreases from 24,750 to 22,870 MPa indicating that the crosslink density of the blends decreases. The SEM analysis shows the absence of phase separation. Moisture absorption and chemical resistance of the blend composites increase with increasing cyanate content. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers  相似文献   
108.
The effect of cross linking of the major whey protein β-lactoglobulin (β-Lg) and major protein fractions (11S) of soybean (Glycinin) and sesame seed (α-globulin) with the microbial enzyme transglutaminase (EC 2.3.2.13) was studied. The formation of polymerized proteins was followed by poly acrylamide gel electrophoresis, gel filtration high pressure liquid chromatography (HPLC) and evaluation of functional properties. Cross linked proteins were less turbid on heating to higher temperature as compared to untreated samples and the temperature at which the protein turns turbid also increased in the treated samples. In case of β-Lg and α-globulin of sesame seed when the control showed turbidity at 60 °C, the enzyme treated sample indicated at 65 °C and higher. Similar results were obtained in the case of soybean also. The treated samples showed higher emulsifying activity when compared to the control. The control showed an emulsifying activity of 0.55 ± 0.02, and the treated sample showed an emulsifying activity of 0.72 ± 0.02 (optical density at 500 nm is taken as emulsifying activity). Foaming capacity did not improve significantly with the enzyme treatment. The complex formed was investigated by gel filtration chromatography. Nearly 30% of the proteins (11S protein fractions and β-Lg) formed the complex and increase in the concentration of the proteins or the enzyme did not show any increase in the complex formation. The changes in the fluorescence intensity indicated changes in the microenvironment of the chromophores induced by the enzymatic cross linking.  相似文献   
109.
A local approach model has been developed for structural assessment of functionally graded materials in which the yield strength and the fracture toughness vary spatially. While the yield strength of the material at any point is taken to be deterministic, the local cleavage toughness is statistically distributed following a two-parameter Weibull model. The model is intended to determine the crack extension direction and failure probabilities of cleavage failure for a stationary pre-crack in a functionally graded material. The effect of independent variation in yield strength and toughness is discussed as a precursor to validating the model using a temperature gradient problem in which the yield strength and toughness are coupled through the temperature. The model is shown to closely reproduce experimental observations from cleavage fracture tests on mild steel subject to a controlled temperature gradient normal to the crack.  相似文献   
110.
International collaboration is becoming an increasingly significant issue in science. During the last few years, a large number of bibliometric studies of co-authorships have been reported. Mostly, these studies have concentrated on country-to-country collaboration, revealing general patterns of interaction. In this study we analyze international collaborative patterns as indicated in the Indian publications by tracking out multi author publications as given in Science Citation Index (SCI) database. Correspondence analysis is used for analysis and interpretation of the results. According to correspondence analysis of the data set, Physics, Chemistry, Clinical medicine are the first, second and third largest subjects having international collaboration. USA, Italy, Germany, France, England are the top five countries with which India is collaborating. The data set shows an association between Physics and Italy, Switzerland, Algeria, Finland, South Korea, Russia, Netherlands contrasting an association between Biology & Biochemistry, Immunology, Ecology & Environment, Geosciences, Multidisciplinary subjects and England, Japan, Canada. It also shows an association between Agriculture and Philippines, Canada, Denmark in contrast to an association between Chemistry and Malaysia, Germany, France. An association between Clinical medicine, Astrophysics and England, Sweden, USA, New Zealand in contrast to an association between Agriculture and Canada, Philippines, Denmark is shown. An association between Engineering, Mathematics, Computer Science, Neuroscience and Singapore, Canada, USA in contrast to an association between Chemistry, Astrophysics and Malaysia, Spain is shown. This association of collaborating countries and disciplines almost tallies with the publication productivity of these countries in different disciplines.  相似文献   
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