Báo cáo vật lý: "EFFECTS OF Si, Al2O3 AND SiC SUBSTRATES ON THE CHARACTERISTICS OF DBRS STRUCTURE FOR GaN BASED LASER" ppsx

... of Physical Science, Vol. 17(2), 151–159, 2006 151 EFFECTS OF Si, Al2O3 AND SiC SUBSTRATES ON THE CHARACTERISTICS OF DBRS STRUCTURE FOR GaN BASED LASER N.M. Ahmed*, M.R. Hashim and ... number of layers. However, MOVPE process parameters for the GaN on alternative substrates need further optimization to reach the quality of GaN layer grown on different substrates (Si, SiC and ... sapphire influencing the GaN device quality and therefore makes commercialization for the GaN devices difficult. The lattice mismatch between 6H SiC and GaN is only 3.3% but SiC substrate has...

Báo cáo vật lý: "Effects of Electrolyte Natures on the Formation of Well-Ordered Titania Nanotubes Produced Via Anodisation" potx

... mouths were opened on the top of the layer, while the tubes were closed by the presence of a layer of titania on the bottom of the structure. Here in, we discuss the influence of different electrolyte ... nanotubes are of interest due to their one-dimensional (1D) nature, ease of handling and simple preparation. Not only can the band gap of the material be altered due to the quantum confinement ... including soft chemical,7 sol-gel8 and anodisation1,9 methods. Among all of these methods, anodisation of titanium allows the formation of highly ordered nanotube arrays demonstrating the most...

Báo cáo khoa học: "Effects of Protein Source and Energy Substrates on the In Vitro Development of Bovine Embryos in a Two-step Culture System" ppsx

... either alone or the absence of both. Therefore, the avoidance of thisnegative effe ct should allow more optimal conditionsto be developed for in vitroproduction.＊Corresponding author: Byeong-chun ... carboxylase and thus plays a key role in the control of fatty acidsynthesis, which stimulates blastocyst formation and the growth of rabbit embryos [7]. A recent study about the effect of citrate on ... containing NEAAalone.In conclusion, the use of a two-step culture system,including the use of a serum-free media at the cleavagestages, followed by the inclusion of serum for the differentiatedstages...

Báo cáo khoa học: " Effects of endomycorrhizal development and light regimes on the growth of Dicorynia guianensis Amshoff seedlings" pptx

... status on the forest floor. This is part of acooperative programme on the determinism of the natur-al regeneration of the tropical rainforest.2. MATERIALS AND METHODS2.1. Site location, seed ... to describe the kinetic of leaf production and shoot growth. At the end of the experiment (350 days), the seedlingswere harvested and the following operations were per-formed:– the total leaf ... sunlight. The use of shelters leads to an alteration of the localclimate. Among the climate parameters, only the temper-ature, read with a minima-maxima thermometer,received further attention, especially...

Báo cáo khoa học: Relationship between functional activity and protein stability in the presence of all classes of stabilizing osmolytes ppt

... affect the association of the substrate with the enzyme in anyone of several ways, e.g. through solvation effects on substrates or enzyme active sites and through theireffects on the thermodynamic ... little or no effect on the solvation properties of the substrate and the enzyme active sites or on theirthermodynamic activities. Another explanation for these observations comes from our DGD° ... complexes [29]. On the other hand,kcat⁄ Kmis an apparent second-order rate constant thatrefers to the properties and the reaction of the freeenzyme and free substrate [29]. We have therefore esti-mated...

Báo cáo khoa học: X-ray crystallography, CD and kinetic studies revealed the essence of the abnormal behaviors of the cytochrome b5 Phe35ﬁTyr mutant pdf

... not form any hydrogen bond with the proteinatoms. The former propionate displays the conservedconformation in the structures of the Phe35ﬁTyr mutant and of the wild-type protein as well as other ... chainconformation of this residue. The shift of the Ca atom of Tyr35 of the Phe35ﬁTyr mutant from that of Phe35 of the wild-type cyt b5is 0.21 A˚, within the error limit. The sidechain of Tyr35 ... resultsdemonstrate that the Phe35ﬁTyr mutant increases not only the afﬁnity of the heme to the polypeptide chain but also the stability of the secondary structure. The kinetics of the heme dissociation...

Báo cáo khóa học: CD38 is expressed as noncovalently associated homodimers on the surface of murine B lymphocytes doc

... suggest that the stabilization of CD38 homodimers by crosslinkers depends strongly on the conformation and orientation between the CD38monomers.It has been reported that NP-40 and Triton X-100stabilize ... these data suggest that these domains are notobligate for the stabilization of the dimers, but rather mustcontribute to the overall stability of the dimers. Crystallo-graphic analysis of the ... values of each of the clones). The relative enzyme activity of each of the mutants is given in parentheses. It was determined by setting the Vmaxadjustedactivity of CD38-WT to 100% and then...

Báo cáo vật lý: "Preparation of ZrO2/Al2O3-pillared Saponite and Its Spectroscopic Investigation on NOX Adsorption" pptx

... Saponite 58 consequently, mesopores prevailed in the pore structure of the systems. In correlation with the XRD pattern data, the possibilities for this condition are the destruction of the ... This is confirmed by the adsorption-desorption isotherm profiles and the pore distribution graphs in Figures 3 and 4, respectively. Although the relationship between the concentration of ZrO2 ... surface area and the formation of the monoclinic zirconia phase. It was found that zirconia dispersion contributed to the enhanced NOx adsorption. Keywords: clay pillarisation, zirconia, dispersion,...

Báo cáo vật lý: "Characterization of Fe-Cr-Al2O3 Composites Fabricated by Powder Metallurgy Method with Varying Weight " ppsx

... Figure 3: (continued) The reinforcement clustering depends on the reinforcement concentration. The effect of reinforcement clustering on the composite is a decrease in the bulk density and an ... the distribution of reinforcement is quite homogeneous. A uniform distribution of reinforcement becomes impossible when the content of reinforcement is higher because of inadequate ratio of ... From the experimental observations, the optimum concentration of reinforcement is 20 wt. % of alumina particles. Figure 4 shows the EDX analysis of the composites to confirm the existence of...

Báo cáo vật lý: "Comparison of the Effects of Organoclay Loading on the Curing and Mechanical Properties of Organoclay-Filled Epoxidised Natural Rubber Nanocomposites and Organoclay-Filled Natural Rubber Nanocomposites" pot

... amounts of organoclay. The improvements of the thermal stabilities of a polymer by hybridising organoclay was due to the layered silicates of organoclay that make the path longer for the thermally ... hydrocarbon in the vulcanisate, whilst a and b are constants. The higher the Qf/Qg values, the lower the extent of the interaction between the filler and the matrix. 2.5 Measurement of Tensile ... compatibility due to the interaction between the epoxy groups of ENR and the amine functionality of the organoclay. This contributed to the better filler-rubber interaction in organoclay-filled...

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