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81.
In this paper we focus on the structural and elastic properties of the B1 phase of SrS by using the modified TBP model, including the role of temperature. We have successfully obtained the phase transition pressures and volume changes at different temperatures. In addition elastic constants and anisotropy factor (A) of B1 phase of SrS at different temperatures are discussed. Our results are comparable with the previous ones at high temperatures and pressures. The elastic properties of the B1 phase of SrS have been discussed with various temperature and pressure. More over the thermal properties like Debye temperature, Thermal expansion coefficient (α) and Gruneisen parameter (γ) and anisotropy factor at high temperatures have also been discussed successfully.  相似文献   
82.
ZnO nanoparticles were synthesized by precipitation method. To reduce the agglomeration among small ZnO nanoparticles, an efficient surface modification method was proposed using 2-aminothiols as a capping agent. The effect of capping reagent is investigated on optoelectronics properties of ZnO. The capping of ZnO with 2-aminothiol leads to the shift in fluorescence intensity and also effected the UV–vis spectra of ZnO. The strategy exposed new dimensions to fine tune the fluorescence signatures of the ZnO.  相似文献   
83.
In the present investigation, a previously isolated Enterococcus faecium KH 24 strain was evaluated for the presence of virulence determinants (agg, esp, efaAfm, gelE, cylA, cylB, clyM, cpd, cob, ccf, ace and hyl), sensitivity to various antibiotics and production of biogenic amines. No virulence determinants were detected, except efaAfm. KH 24 was found to be sensitive to most of the tested antibiotics and none of the biogenic amines were produced by it. Moreover, KH 24 showed good in vitro tolerance to biological barriers and furthermore, its survival in gut of mice was also evaluated. Mice group fed with E. faecium KH 24 strain showed better weight gain and nearly 1 log cfu/g decrease in Salmonella enteritidis counts in the intestines as compared to control (p < 0.05). Enhanced growth of lactobacilli (p < 0.05) and decrease in coliform counts (p < 0.05) were also observed in test group. E. faecium KH 24 is, therefore, found to be a safe strain and it may be used as protective culture or as a probiotic in food preparations.  相似文献   
84.
By combining in situ X-ray photoemission spectroscopy, ex situ high resolution transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy, we show that chemical vapor deposition (CVD) on vertically aligned ZnO nanorods can synthesize different carbon nanostructures (CNs), whose morphology is driven by the ZnO nanorods and whose dimensions and structures change as a function of the process temperature. The CNs range from amorphous carbon cups, completely covering the nanorods, to high density one-dimensional carbon nano-dendrites (CNDs), which start to appear like short hairs on the ZnO nanorods. The nanorods are partially etched when the process is done at 630–800 °C, while they are completely etched at temperatures higher than 800 °C. In the latter case, CNDs emerge from a porous carbon sponge formed at the substrate interface but they are preferentially aligned along the location of the pristine ZnO nanorods. When used as a chemiresisitor the CND–ZnO structures have a higher sensitivity to ammonia compared to chemiresistors made by bare ZnO nanorods, to other one-dimensional CNs, like carbon nanotubes or other metal/metal-oxides hybrid CNs.  相似文献   
85.
Rifampicin, one of the main first line anti-TB drugs, shows variable bioavailability in different marketed preparations and reasons cited include physiological, degradation, manufacturing/ processing, solid state, and bioavailability assessment procedure. Although the amorphous form of a drug is expected to exhibit higher solubility, the amorphous rifampicin has been reported to have a solubility disadvantage as compared to crystalline form II, which is used in marketed preparations. Amorphous form was generated and characterized by solid-state characterization techniques. Physical powder mixtures of form II with varying amounts of amorphous form were prepared, which were then subjected to solid-state characterization techniques and further evaluated for their dissolution behavior. Differential scanning calorimetry (DSC) scans show that area enclosed by integral of melting endotherm can be used for quantification of crystalline component, which can then be used to estimate amorphous content. No definite trend was evident in powder dissolution of mixtures that could implicate solubility difference of amorphous form. Intrinsic dissolution rate (IDR) results indicate that amorphous content has no effect on dissolution profiles of crystalline rifampicin.  相似文献   
86.
Journal of Materials Science: Materials in Electronics - Au nanoparticles are synthesized in a fullerene C60 matrix using the thermal co-evaporation technique. Fullerene C60 is chosen due to its...  相似文献   
87.
This article deals with the numerical simulation of cracked plate using extended isogeometric analysis (XIGA) under different loads and boundary conditions. The plate formulation is done using first-order shear deformation theory. The crack faces are modeled by the Heaviside function, whereas the singularity in stress field at the crack tip is modeled by crack tip enrichment functions. The stress intensity factors for the cracked plate are numerically computed using a domain-based interaction integral. The results obtained by XIGA for the center and edge crack plate are compared with extended finite element method and/or literature results for different types of loads and boundary conditions.  相似文献   
88.
This paper deals with the influence of binary co-deposition of Ag and Cu metals on TiO2 photocatalyst to investigate its adsorption, optical and photocatalytic properties relative to monometallic (Ag/Cu) deposition. Hence, different proportion of Ag and Cu has been simultaneously deposited on TiO2 in an inert (argon) atmosphere under UV irradiations. It was found that the plasmonic absorption bands appeared in the visible region (480 and 640?nm for Ag and Cu, respectively) due to the binary deposition of Ag-Cu nanoparticles (~9–20?nm) onto TiO2 surface as revealed by TEM size analysis and EDS/elemental mapping. The fluorescence spectrum of Ag-Cu-TiO2 showed higher quenching of emission peak intensities at λ?>?450?nm in a different extent due to efficient charge separation as compared to respective monometallic (Ag/Cu)-TiO2 nanocomposites. The photocatalytic activities of binary Ag-Cu-TiO2 for the degradation of methylene blue and salicylic acid under UV and visible irradiations were found to be notably higher than monometallic deposited TiO2. The reaction rates and CO2 formation exhibited due to binary deposition always gives enhanced photoactivity which could be useful for removal of toxic environmental pollutants under solar radiations.  相似文献   
89.
In this paper, we present a critical review of the current layout of alphabets on a mobile keypad and seek to improvise it for optimized text entry to facilitate user interaction with or without the use of predictive text input techniques. Currently, most mobile phones use multi-press as the preferred method of text entry though they also offer word-based disambiguation schemes. However, keypad layouts are not optimized for text entry using word based disambiguation schemes as several matches exist for the same numeric combination, some of which are frequently used words. This scheme effectively slows down text entry speeds, requiring more tapping for disambiguating matches. The proposed model seeks to reduce the number of matches for any possible numeric combinations, by optimization of keypad layout by repositioning alphabets on the keypad. For users not using dictionary, our model requires lesser tapping for commonly used alphabets and groups commonly used key combinations together such as in a computer keyboard.The proposed model was derived by simulation of the mobile phone keypad on a computer system and it uses cognitive agents to derive the most optimum keypad layout. Our model uses frequently used English words from a dictionary and attempts to minimize the number of matches for any given numeric key combinations, though the same could easily be duplicated for other languages. The model is expected to cause a significant rise in the text input speeds of mobile phones and other embedded devices with limited text entry capabilities, leading to better usability and customer satisfaction.  相似文献   
90.
Several pathways for potentially greenhouse gas neutral production of ammonia have been investigated compared to today's conventional ammonia production at chemical sites in Antwerp, Dormagen, and Geleen. These pathways include on-site water electrolysis using grid electricity, off-site production via water electrolysis using renewable electricity and supply of green hydrogen to the site, pyrolysis of natural gas and conventional ammonia production coupled with CO2-capture on-site and transport to a storage site. All pathways effectively eliminate scope 1 emissions present in conventional production but continue to emit scope 2 emissions from grid electricity consumption. Eventually, a coordinated industry-wide and cross-industry effort is needed to address the transformational changes and develop the common cross-border infrastructures.  相似文献   
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