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81.
The bark and wood of Sonneratia caseolaris (L.) Engl. have been analyzed for chemical profile by GC–TOFMS. Overall thirty-two compounds from bark and twenty-eight compounds from wood have been detected. Sixteen constituents have been found to be common in both the extracts. GC–TOFMS chemical profile may be a significant finger print chemotaxonomic marker as an identity of this plant.  相似文献   
82.
Composite solid electrolytes in the system (1 − x)LiNO3-xAl2O3, with x = 0.0-0.5 were synthesized by sol-gel method. The synthesis carried out at low temperature resulted in voluminous and fluffy products. The obtained materials were characterized by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy/energy dispersive X-ray, Fourier transform infrared spectroscopy and AC impedance spectroscopy. Structural analysis of the samples showed base centred cell type of point lattice of LiNO3 for the composite samples with x = 0.1-0.2 and body centred cell for the sample with x = 0.3. A trace amount of α-LiAlO2 crystal phase was also present in these composite samples. The thermal analysis showed that the samples were in a stable phase between 48 °C and 230-260 °C. Morphological analysis indicated the presence of amorphous phase and particles with sizes ranging from micro to nanometre scale for the composite sample with x = 0.1. The conductivities of the composites were in the order of 10−3 and 10−2 S cm−1 at room temperature and 150 °C, respectively.  相似文献   
83.
An efficient and low noise short wavelength band erbium-doped fibre amplifier (S-band EDFA) is proposed and demonstrated using double-pass configuration. This amplifier provides a gain of 1500 nm signal as high as 26.9 dB, which is 9.6 dB higher than the two-stage single-pass amplifier. The corresponding noise figure obtained is 7.5 dB, which is of the same level as in the single-pass amplifier and more than 2 dB lower than the previously reported double-pass amplifier [IEIOE Electron. Express 2 (2005) 182]. The gain enhancement is due to the double pass-propagation of the test signal in the second stage, which increases the effective erbium-doped fibre (EDF) length. The low noise is attributed to the optical circulator between EDFs, which prevents the backward amplified spontaneous emission from propagating into the input part of the amplifier. The proposed amplifier is expected to play an important role in the development of a practical S-band EDFA.  相似文献   
84.
For purposes of comparison of the accuracies of the Hartree-Fock Cluster and Discrete Variational Method Cluster procedures currently in use for investigation of hyperfine properties of solid state systems, we have studied by both procedures the nuclear quadrupole interactions and silicon-halogen bond distances in the monohalosilane systems SiH3X(X=F, Cl, Br and I). Very good agreement is found between the results by the two procedures and with experiment.  相似文献   
85.
In this work, an extensive analysis on direct contact membrane distillation (DCMD) performance was developed to estimate the mass flux and the heat efficiency, considering transport phenomena, membrane structural properties and most sensitive process parameters, with the aim to provide optimization guidelines for materials and methods. The results showed that an increase of the temperature gradient resulted in the enhancement of both transmembrane flux and thermal efficiency. The investigation of the effects of membrane properties confirmed that better DCMD performance was achieved when using polymeric membranes characterized by low thermal conductivity (flux and thermal efficiency declined by 26% and 50%, respectively, when increasing thermal conductivity from 0.1 to 0.5 W/m K), and high porosity. An optimal thickness value (around 0.7 mm) was identified when operating at low temperature gradient (<5 °C). However, at higher temperature gradient (>10 °C), increasing the membrane thickness from 0.25 to 1.55 mm resulted in a flux decay of about 70% without a significant improvement in thermal efficiency.  相似文献   
86.
Mechanics of Composite Materials - The conventional wood-based composites contain an unreacted free formaldehyde, which causes a cancerous effect on humans. To overcome this problem,...  相似文献   
87.
In this note we give an improvement to a recent result obtained by Savas and Rhoade concerning ∣Ak summability of infinite series.  相似文献   
88.
以居民对援疆政策满意度为出发点,前学者的研究基础上确定援疆政策效果的满意度的衡量指标,选取6个大方向31个指标来测量援疆效果满意度.通过南疆三地州进行实地问卷调查获得数据为样本,采用因子分析方法确定二级指标及三级指标的权重,进行对援疆政策效果满意度综合评价.研究结论是南疆居民对援疆效果的满意度总得分接近70分,说明总体满意度较高,其中满意度最高的为收入及补贴,排在第一位,排在末尾的就是教育领域,排在第二位的是住房建设,而基层服务的满意度仅仅高于教育领域,排在第五位.排在第三位的就是医疗,第四位才是居民出行为核心内容的基础设施建设.从而为援疆政策效果满意度优化,解决存在的问题,全面改善援疆政策效果提出政策建议.  相似文献   
89.
90.
Evidence shows that honey improves glycemic control in diabetes mellitus. Besides its hypoglycemic effect, studies indicate that honey ameliorates lipid abnormalities in rats and humans with diabetes. The majority of these studies do not examine the mechanisms by which honey ameliorates glycemic and/or lipid derangements. The gut microbiota is now recognized for its ability to increase energy harvest from the diet and alter lipid metabolism of the host. Recently available data implicate a causal role of these gut microbes in the pathophysiology of obesity, insulin resistance, and diabetes mellitus. In this review, we present some of the latest findings linking gut microbiota to pathogenesis of obesity, insulin resistance, and diabetes mellitus. The review also underlines data that demonstrate the beneficial effects of oligosaccharides on various abnormalities commonly associated with these disorders. Based on the similarities of some of these findings with those of honey, together with the evidence that honey contains oligosaccharides, we hypothesize that oligosaccharides present in honey might contribute to the antidiabetic and other health-related beneficial effects of honey. We anticipate that the possibility of oligosaccharides in honey contributing to the antidiabetic and other health-related effects of honey will stimulate a renewed research interest in this field.  相似文献   
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