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991.
Recently, renewable energy resources and their impacts have sparked a heated debate to resolve the Australian energy crisis. There are many projects launched throughout the country to improve network security and reliability. This paper aims to review the current status of different renewable energy resources along with their impacts on society and the environment. Besides, it provides for the first time the statistics of the documents published in the field of renewable energy in Australia. The statistics include information such as the rate of papers published, possible journals for finding relative paper, types of documents published, top authors, and the most prevalent keywords in the field of renewable energy in Australia. It will focus on solar, wind, biomass, geothermal and hydropower technologies and will investigate the social and environmental impacts of these technologies.  相似文献   
992.
Protection of Metals and Physical Chemistry of Surfaces - Single NbSi2 and duplex NbSi2/Nb5Si3 coatings were successfully applied on Nb substrates using halide activated pack cementation (HAPC)...  相似文献   
993.
Membrane filtration of biomass is usually accompanied by significant flux decline due to cake‐layer formation and fouling. Crossflow filtration with flux controlled by pumping the permeate can produce stable fluxes if a ‘critical flux’ is not exceeded. Below critical flux the transmembrane pressure is typically very low and increases linearly with imposed flux. Above the critical flux the transmembrane pressure rises rapidly signifying cake‐layer formation which is usually accompanied by a continued rise in transmembrane pressure and/or a drop in delivered flux. A range of microfiltration and ultrafiltration membranes with pore sizes from 0.22 to 0.65 µm and molecular weight cut‐off of 100 kDa was used. The feed was an activated sludge mixed liquor with concentration in the range of 3–10 g dm−3. The results show that the critical flux depends on feed concentration and crossflow velocity, being higher for higher crossflow velocity or lower feed concentration. Critical flux was also dependent on membrane type, being lower for hydrophobic membranes. Although the transmembrane pressure was higher for the larger pore size membrane, no significant difference in critical flux was observed among different pore size membranes. © 1999 Society of Chemical Industry  相似文献   
994.
995.
This work aimed to investigate the drying behavior of melon seed during combined fluidized bed-microwave drying system. Three drying air temperatures (40, 55 and 70 °C), three microwave powers (270, 450 and 630 W) and three air velocities (0.8, 1.5 and 2.3 m/s) were tested. Five mathematical models were selected to fit the experimental data for drying kinetics, and the results revealed that the Aghbashloo et al. model exhibited, in all cases, the best performance in fitting the experimental data (R2 varying from 0.99088 to 0.99998; χ2 from 0.00000 to 0.00185 and RMSE from 0.02289 to 0.82316). Calculated values of moisture diffusivity for dried melon seed varied from a minimum of 6.51 × 10?10 to a maximum of 6.59 × 10?9 m2/s under the tested drying conditions. Moisture diffusivity values increased as air temperature and microwave power was increased. Shrinkage values were calculated and found to vary in the range from 46.99 to 15.09 %.  相似文献   
996.
Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers—Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine® and jetPRIME®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy.  相似文献   
997.
Shelf life of several marine fish species of Bangladesh during ice storage   总被引:1,自引:0,他引:1  
Organoleptic, biochemical and bacteriological aspects of five tropical marine fish such as silver jewfish, Bombay duck, big-eye tuna, Chinese pomfret and ribbon fish stored in ice were studied. Organoleptically all fish were found acceptable for 10–13 days before becoming inedible. Proximate analysis showed that moisture content increased slightly; protein and lipid content decreased gradually and ash had little or no significant change. pH, TVB-N, peroxide and aerobic plate count values increased with increasing storage period but the values were within acceptable range up to 10 days of storage. Changes in myofibrillar ATPase activity and solubility of these fishes showed that Ca2+ ATPase in the presence of both 0.1  m and 0.5  m KCl decreased gradually whereas no marked changes were observed in the Mg+2 ATPase activities in the presence/absence of Ca+2. Myofibrillar protein solubility of all fish samples also decreased considerably during ice storage. The decrement in Ca2+ ATPase activity and solubility indicates denaturation of myofibrillar protein of fish samples during ice storage.  相似文献   
998.
To compare the antioxidant and antiradical activity of Amygdalus communis L. hulls and shells phenolic extracts in different genotypes, 18 A. communis L. genotypes were selected from those in Qooshchi, Qalgachi, Qovarchin Qale, Najaf Abad, Jamal Abad, Kahriz, Sfahlan of West and East Azerbayjan provinces of Iran in 2007. The fruits of these almonds were collected, their hulls and shells dried, ground and then methanolic extracts prepared from these hulls and shells. Total phenolic content was determined using the Folin–Ciocalteu (F–C) method. The extracts’ reducing power and scavenging capacity for radical nitrite, hydrogen peroxide and superoxide were evaluated. Significant differences were found in phenolic content of hulls and shells among various genotypes, radical scavenging capacity percentage varied significantly among genotypes and their hulls and shells. S3-7 genotype with the highest phenolic content and antioxidant activity in its hulls represents a valuable genotype for procuring antioxidant phenolic compounds.  相似文献   
999.
We consider the many-help-one problem, also called m-helper problem, for the special case of m = 1 where one source provides partial side information to the fusion center (FC) to help reconstruction of the other correlated source. Both correlated sources communicate information about their observations to the FC through an orthogonal multiple access channel (MAC) without cooperating with each other. First, we characterize the optimal tradeoff between the transmission cost, that is, power, and the distortion D. Then, we consider a joint optimization of source coding and power scheduling from an information theory perspective, where the power scheduling is verified using Shannon capacity formula and the source-coding problem is analyzed using rate-distortion theory. We show that the joint optimization in the Gaussian one-helper problem can be solved analytically. We provide closed-form expressions for the optimal distortion and the optimal power scheduling in terms of the cost weights. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
1000.
Peroxidase-catalyzed template-guided polymerization of aniline in the presence of γ- alumina nanosheet (NS) particles have been carried out in aqueous media and γ-Al2O3/PANI nanocomposite was obtained. The polymerization of aniline occurred in aqueous solution in the presence of SPS (sulfonated polystyrene) as a template and SDS (sodium dodecyl sulfate) as a surfactant. Both obtained nanocomposites were comparable by SEM images. It was demonstrated that the γ-Al2O3 NS/PANI-SPS nanocomposite has higher conductivity and the γ-Al2O3 NS/PANI-SDS nanocomposite has higher void areas. The higher conductivity of γ-Al2O3 NS/PANI-SPS nanocomposite is attributed to the higher coated areas of γ-Al2O3 NS during polymerization in comparison with γ-Al2O3 NS/PANI-SDS which are not coated efficiently as the former. The FT-IR studies showed that the γ-Al2O3 NS/PANI nanocomposite was formed by interaction of the polyaniline (PANI) and γ-Al2O3 NS. FTIR also showed that the amount of PANI in γ-Al2O3 NS/PANI-SPS is more than in γ-Al2O3 NS/PANI-SDS. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers  相似文献   
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