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21.
A state of the art proteomic methodology using Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI TOF) has been employed to characterize peptides modulated in the date palm stem subsequent to infestation with red palm weevil (RPW). Our analyses revealed 32 differentially expressed peptides associated with RPW infestation in date palm stem. To identify RPW infestation associated peptides (I), artificially wounded plants (W) were used as additional control beside uninfested plants, a conventional control (C). A constant unique pattern of differential expression in infested (I), wounded (W) stem samples compared to control (C) was observed. The upregulated proteins showed relative fold intensity in order of I > W and downregulated spots trend as W > I, a quite interesting pattern. This study also reveals that artificially wounding of date palm stem affects almost the same proteins as infestation; however, relative intensity is quite lower than in infested samples both in up and downregulated spots. All 32 differentially expressed spots were subjected to MALDI-TOF analysis for their identification and we were able to match 21 proteins in the already existing databases. Relatively significant modulated expression pattern of a number of peptides in infested plants predicts the possibility of developing a quick and reliable molecular methodology for detecting plants infested with date palm.  相似文献   
22.
Here, we report on the effect of BaF2 powder addition on the mechanical synthesis of Ce3+-doped Y3Al5O12 (Y2.97Al5O12:Ce0.033+, YAG:Ce3+) phosphors for white light emitting diodes. The YAG phosphors were synthesized by the mechanical method using an attrition-type mill. When BaF2 was added at 6 wt% to the raw powder materials and milled, the synthesis of YAG:Ce3+ was favorably achieved at the vessel temperature of 255 °C, which was about 1200 °C lower than the YAG phosphor synthesis temperature by solid-state reaction. The synthesized YAG:Ce3+ phosphor revealed the maximum internal quantum yield of 57%.  相似文献   
23.
Fracture limits in sheet stretch bending were theoretically obtained on the assumption that the fracture occurs when the stretching force reaches its maximum value. From the calculated results, a fracture criterion has been presented where limit wall stretch, Lmax/L0 (Lmax: limit wall length of a sheet, L0: initial wall length), is explicitly given as a function of the non-dimensional bending curvature, t0/R (t0: sheet thickness, R: bending radius) and the material's work hardening exponent (n-value). To verify this criterion, three-point stretch bending tests with various punch-radii were performed on three types of aluminum sheets (A5182-O, JIS6061-T4 and JIS6N01-T5). The predicted limit wall stretch, as well as limit forming height, were in good agreement with the experimental results.  相似文献   
24.
Various types of polymers containing tert‐butoxycarbonyl (BOC) moiety as the typical protecting group of functional moieties have been used for the design of stimuli‐responsive polymer materials. In this study, we investigated the heat‐responsive deprotection behavior of BOC‐containing polymers obtained by radical polymerization of 4‐(tert‐butoxycarbonyloxy)styrene (BSt) and copolymerizations of BSt with styrene and methyl acrylate. The deprotection of BOC groups accompanying the evolution of isobutene and carbon dioxide as gaseous products was monitored by thermogravimetric analyses at different temperature circumstances; that is, on heating at a rate of 10 °C/min and under isothermal conditions at various temperatures. The deprotection resulted in a significant decrease in the transmittance of visible light due to the formation of a large number of gas bubbles, that is, foaming, in the polymer films when a heating temperature was close to the glass transition temperature of the used polymer. The potential of BOC‐containing polymers was also evaluated as the heat‐responsive adhesive polymers for dismantlable adhesion. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46252.  相似文献   
25.
Crosslinking and decrosslinking reactions of poly(vinyl alcohol) (PVA) and poly(vinyl acetate) (PVAc) using an alternating copolymer of maleic anhydride and 2,4‐dimethyl‐1,3‐pentadiene (PMAD) as the polyfunctional crosslinker and subsequent ozone degradation are reported. PVA and PVAc are heated at 200 °C for 0.5 to 3 h in the presence of 5 to 30 wt % of PMAD in the solid state to obtain the corresponding crosslinked polymers. The reactions of a hydroxy group of PVA and an acetate group of PVAc with an anhydride group of PMAD slowly proceed to give insoluble polymers with a loose crosslinking structure. Almost no change in the thermal decomposition temperatures and the IR spectra is observed during the crosslinking reactions. The crosslinked PVA produces hydrogels with a high swelling ratio of 500 to 1700%, which are readily degradable during a reaction with ozone in water at 0 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44229.  相似文献   
26.
The behavior of sand crushing will appear when the confining pressure is up to a certain value, which results in disappearing of the positive dilatancy of sand. Adopting a new hardening parameter with the crushing stress, an elastoplastic constitutive model considering sand crushing is proposed. Comparing the conventional triaxial compression test results with the model prediction, it shows that the proposed model can reasonably describe the dilatancy of sand from positive to negative.  相似文献   
27.
Through the (1)H and (13)C NMR measurements for the symmetrical beta-diketones such as 2,4-pentanedione and 1,3-diphenyl-1,3-propanedione and unsymmetrical one such as 1-phenyl-1,3-butanedione at various concentrations and temperatures, we confirmed that 1-phenyl-1,3-butanedione in CDCl(3) exists as monomers in its relatively low concentration. In addition, the 1-phenyl-1,3-butanedione in CDCl(3) exists not as a keto-form but as two kinds of cis-enol forms. The proton transfer between the two kinds of cis-enols for 1-phenyl-1,3-butanedione was discussed thermodynamically; it is concluded that the OH proton of enol of 1-phenyl-1,3-butanedione is considerably located near the oxygen atom attached to the carbon atom linking to a phenyl group.  相似文献   
28.
The present paper reports on research on the effect of molecular structure of polymer dispersants on the relationship between the electrosteric interaction of dispersants on solid surfaces and the viscosity of suspensions. Ammonium polyacrylate with different hydrophilic to hydrophobic ratios ( m:n ) was prepared and added to dense Al2O3 suspensions (40 vol%). The steric interactions and adsorbed structures of dispersants on Al2O3 powders were examined under an atomic force microscope (AFM). An optimum hydrophilic to hydrophobic group ratio, which was obtained from the maximum repulsive force and the minimum viscosity of suspension, was determined at m :n = 3:7. The changing mechanism of the adsorbed structure and the steric interaction of dispersants and the suspension viscosity by the hydrophilic to hydrophobic molecular ratio were discussed by comparing the experimental force curve and DLVO theory.  相似文献   
29.
γ—TiAl单晶中,<011]超点阵位错的运动方向同晶体取向有关、当沿极射投影图001一110—010单位三角形的001-111-021区域中的取向变形时,SISF偏位错为领先位错;而沿三角形中其余区域中的取向变形时,APB偏位错为领先位错.在反常温度区域中(即超点阵位错开动的温度范围内),前者的CRSS较高,形变的热激活焓也较高,<011超点陈位错的脱钉过程更为困难,造成CRSS反常上升的速率较快.  相似文献   
30.
Numerical simulations of combined natural convection–conduction in a droplet of n-dodecane suspended from a thermocouple were carried out, taking into consideration evaporation, and the effect of thermocouple diameter on the evaporation characteristics was investigated. The calculated temperature history of the droplet is in good agreement with experimental results; both show that the rate of heating decreases with increasing thermocouple diameter. The maximum error in temperature due to the thermocouple increases linearly with increasing thermocouple diameter. Thus, in investigations involving a droplet suspended from a thermocouple, it is preferable to use a thermocouple with the smallest possible diameter.  相似文献   
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