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81.
ABSTRACT

A set of coupled heat, mass, and pressure transfer equations was used to describe the moisture adsorption process in gmn kernels. The finite element method was used to solve the system of equations. The technique was applied to analyze the temperature, moisture, and pressure distribution in a barley kernel during soaking with steep water. The temperature and moisture distributions with (heat, mass, and pressure transfer model) and without (heat and mass uansfer) the effect of pressure were simulated for assumed conditions. The results obtained from the heat, mass, and pressure transfer model show a marked difference from the results obtained from the heat and mass transfer model. This indicated that a pressure gradient exists during the transfer Process, causing additional moisture movement due to filtration effect. Hence. the pressure tern cannot be assumed constant during the moisture adsorption process. The simulated temperature, moisture and pressure profiles and gradients can be used for determining the optimum time required for solking kernels with sleep water to produce barley malt.  相似文献   
82.
A series of 1‐arylsulfonyl‐5‐(N‐hydroxyacrylamide)indolines ( 7 – 15 ) has been developed; the compounds exhibited potent histone deacetylase (HDAC) inhibitory activities. Notably, almost all of this series exhibited better HDAC‐inhibitory and antiproliferative activities than 3‐(1‐benzenesulfonyl‐1H‐indol‐5‐yl)‐N‐hydroxyacrylamide ( 6 ), as reported in a previous study. Among these compounds, 3‐[1‐(4‐methoxybenzenesulfonyl)‐2,3‐dihydro‐1H‐indol‐5‐yl]‐N‐hydroxyacrylamide ( 9 ) showed a two‐ to tenfold increase in activity compared to SAHA ( 1 ) in the suppression of lipopolysaccharide‐induced cytokine production. Compound 9 also caused a marked reduction in carrageenan‐induced acute inflammation in a rat model. Taken together, these data indicated that 1‐arylsulfonyl‐5‐(N‐hydroxyacrylamide)indolines HDAC inhibitors exhibit potent anti‐inflammatory activity.  相似文献   
83.
For the diffusion-controlled adsorption, the expression of dynamic surface adsorption Γ(t) was ob-tained by solving the diffusion equation. Two cases, i.e. the short and long time limits, were mainly d...  相似文献   
84.
A novel petrosiacetylene analog (petrosiacetylene E) has been isolated from the Korean marine sponge Petrosia sp., along with petrosiacetylene A, B and C. Their structures were elucidated on the basis of spectroscopic methods and the stereochemistry of the new compound was determined by using the modified Mosher’s method. Petrosiacetylene E showed higher cytotoxicity against five human cancer cell lines than petrosiacetylene A and B, presumably due to the additional hydroxy group located at C-16.  相似文献   
85.
通过对7根不卸载的混凝土梁进行预应力CFRP布加固后的荷载试验,研究了不同的初始弯矩对构件受弯性能的影响和作用.试验研究表明,初始弯矩的存在使构件的受弯性能明显降低,并且随着初始应力水平的增加,降低作用更加明显.  相似文献   
86.
Two new complexes, [M2(L)2(bpy)2](ClO4)2 [L = methyl salicylate, bpy = 2,2′-bipyridine, M = Cu (1) and Zn (2)] have been synthesized and structurally characterized by X-ray structure analyses. The centrosymmetric dimeric structure consists of a binuclear unit, in which M (M = Cu or Zn) atoms are bridged by two phenol oxygen atoms as a μ 2-bridged. The neighboring binuclear units interact with each other by two kinds of weak contacts: one kind is π–π stacking by π–σ attraction with an edge-to-face C–H···π interaction, and the second type is a H-bonding interaction, which extends the binuclear unit into a 3D network. Magnetic measurements confirm that 1 presents a very strong intradinuclear ferromagnetic coupling between the copper(II) ions.  相似文献   
87.
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89.
The non-equilibrium grain boundary co-segregation of boron and magnesium in Ni3Al–B–Mg alloys was determined by Auger electron spectroscopy (AES) in conjunction with ion sputtering in a cooling rate range of 0.05–269 K/s from temperatures of 1023, 1223 and 1373 K. The analytical expressions of diffusion rate equations describing non-equilibrium segregation process based on the concept that mobile solute-vacancy complexes migrating to grain boundaries is responsible for non-equilibrium grain boundary segregation of solute atoms in an alloy was used to simulate well the experimental results. The diffusion coefficients for boron atoms, boron-vacancy complexes, magnesium atoms and magnesium-vacancy complexes were determined, and the binding energy of boron-vacancy and magnesium-vacancy complexes was estimated.  相似文献   
90.
Structural and optical studies have been performed on GaN, InGaN layers, In0.08Ga0.92N/GaN heterostructures, In0.08Ga0.92N/In0.02Ga0.98N single and multiquantum wells grown by metal organic chemical vapor deposition (MOCVD) and GaN by molecular beam epitaxy (MBE) on GaN templates by using transmission electron microscopy (TEM), X-ray diffraction (XRD), and photoluminescence (PL). The layers are found to be high quality with low defect density, on the order of 106 cm?2, which are mainly related to the threading dislocations originating/propagating from the hydride vapor phase epitaxy (HVPE) GaN template. The interface between the layers and substrate could not be detected by TEM and was therefore deemed to be of high quality. Convergent beam electron diffraction studies revealed that the polarity of the films is Ga-polarity, which is the same as that of the substrate. A dual structure with different compositions and having thicknesses of 10 and 25 nm was observed in InGaN layers grown on GaN in one of the heterostructure samples. The full width at half maximum (FWHM) of the XRD rocking curves of (0 0 0 2) for heterostructures and quantum wells were found to be in the range of 15–28 arcmin for a slit width of 2 mm. PL studies on GaN layers grown by MBE and MOCVD on GaN templates are reasonably similar. The PL spectra from all the MBE and MOCVD epilayers and the substrate contain a plethora of sharp peaks related to excitonic transitions. With the presence of donor-bound exciton peaks and their associated two-electron satellites, the binding energies of two distinct shallow donors (28.8 and 32.6 meV), which are attributed to Si and O, respectively, were determined. PL measurements revealed that the FWHM of the main donor bound exciton peak increased from 0.6 to 2.9 meV but no change in peak position (3.472 eV) was observed in GaN when doping with Si (5×1017 cm?3). However, the intensities of the yellow band and the shallow donor–acceptor pair band increased 10 times as compared to that in the undoped GaN samples. In the case of InGaN/GaN heterostructures, a similar trend was observed when compared to the doped samples. In the multiquantum well In0.08Ga0.92N/In0.02Ga0.98N heterostructures, the activation energy of the exciton emission, found to be 18 meV, was the lowest in the samples studied. The peak at 3.02 eV related to the InGaN was strongly pronounced in the In0.08Ga0.92N/In0.02Ga0.98N multiquantum well structure. In the In0.08Ga0.92N/In0.02Ga0.98N quantum well structures, the change in peak position with variation of temperature from 15 to 300 K in PL spectra is “S”-shaped. The cause for the “S” shape, i.e., a red–blue–red shift, is discussed.  相似文献   
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