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101.
Many scenarios have been generated in the last years analysing the international energy market. The variety of these scenarios is manifold, as they are generated by different institutions using different methodological approaches and different framework assumptions. However, these scenarios can roughly be classified into three main groups: “moderate”, “climate protection” and “resource scarcity and high fossil fuel prices”. Analysing the German energy market makes a fourth scenario group necessary, which considers the possible revision of the decided nuclear energy phase out. Most of the existing scenarios developed by different institutions can be allocated into one of these groups. A representative scenario for each group has been selected to illustrate the development of the energy sector until 2030. Contrary to the worldwide primary energy demand (PED), the German PED decreases in each scenario, even though the drop differs strongly throughout the scenarios. On the other hand the structure of the PED in 2030 varies strongly for each scenario, especially regarding the share of fossil energy sources. However, a common robust result can be observed throughout all scenarios, namely the high increase in the share of the renewable energy resources, although the scenario generation processes are not always robust.  相似文献   
102.
选用元素分析仪测定大气气溶胶样品中的总氮含量,并使用总有机碳分析仪和离子色谱仪分别获得水溶性总氮和水溶性无机氮组分的含量;在此基础之上,通过相差法获得气溶胶中的水溶性有机氮和非水溶性氮组分含量;对本方法的精确度和准确度进行评估,及使用此方法对西安市大气细颗粒物PM2.5中含氮组分的进一步分析。结果表明,本方法能够系统准确地测试大气气溶胶中的多种含氮组分含量,可操作性强。  相似文献   
103.
利用淀粉为原料,与丙烯酸接枝共聚制备了高吸水性树脂,考察了糊化温度、聚合反应时间、丙烯酸单体中和度等因素对接枝产物吸水性能的影响,并比较了吸自来水、蒸馏水及盐水情况。  相似文献   
104.
ANTIOXIDANT PROPERTIES OF POLYPHENOLS EXTRACTED FROM GREEN AND BLACK TEAS   总被引:6,自引:0,他引:6  
The catechins, including epicatechin gallate (ECG), epigallocatechin (EGC), and epigallocatechin gallate (EGCG), and the theaflavins, including theaflavin (TF), theaflavin monogallate (TF-1), and theaflavin digallate (TF-2), were extracted from green tea and black tea, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability, superoxide-scavenging efficiency, and lipid oxidation-inhibition ability of the pure compounds listed above as well as epicatechin (EC), carnosol, carnosic acid, and butylated hydroxytoluene (BHT) were investigated.
The DPPH radical-scavenging ability of the catechins was EGCG > ECG > EGC > EC and of the theaflavins was TF-2 > TF-1 > TF. EGCG, ECG, EGC, TF-2, TF-1, and TF showed higher DPPH radical- and superoxide-scavenging abilities than carnosol, carnosic acid, and BHT. EGCG, ECG, EGC, carnosol, and carnosic acid showed higher lipid oxidation-inhibition activity, as measured by the Rancimat method, than BHT and theaflavins.  相似文献   
105.
Regular frankfurters treated with tofu powder had decreased fat with no significant differences in color, texture, or overall acceptability compared to a control by sensory analysis. Lean frankfurters with tofu powder had lower moisture and color, better texture, and overall acceptability with no flavor differences from controls. Except for fracturability, there were no differences in texture-related parameters by Texture Profile Analysis (TPA) between regular and control frankfurters but treated lean frankfurters had improved texture. Lean pork sausages treated with tofu powder were lower in fat, higher in protein, and moisture with no differences in sensory attributes compared to controls.  相似文献   
106.
Both white kidney bean α-amylase inhibitors WKB 858A (MW 42,000) and WKB 858B (MW 20,000) were composed of two subunits as determined by N-terminal amino acid analysis by amino acid sequence, by SDS-PAGE and by separation on a chromatofocusing column in 8 M urea. N-Terminal amino acids for Inhibitor WKB 858A were alanine and glycine, with a sequence of H2N-Ala-Glu-Asn-Ala-Gly-Thr-Tyr–COOH for deglycosylated 9,000 MW peptide and H2N-Gly-Asn–COOH for deglycosylated 12,000 MW peptide. N-Terminal amino acids for Inhibitor WKB 858B were alanine and serine, with a sequence of H2N-Ala-Thr-Glu-Thr-Ser–COOH for the deglycosylated 9,000 MW peptide and H2N-Ser-Ala-Val-Gly-Leu-Asp-Phe-Val-Leu-Val-Pro-Val-Gin-Pro-Glu-Ser-Lys-Gly-Asp-Thr-VaVal-Glu-Phe-Asp–COOH for the deglycosylated 15,000 MW peptide. Chemical modification of 2 of 7 His residues with diethylpyrocarbonate resulted in 26% loss of inhibitory activity. Modification of 1.5 of 7 Trp residues with N-bromosuccinimide gave 60% loss of inhibitory activity. Modification of 2 of 6 Tyr residues with N-acetylimidazole gave 60% loss of inhibitory activity. Modification of 3.6 of 6 Arg residues with p-hydroxyphenylglyoxal gave 64% loss of inhibitor activity. These results indicate the possible importance of one or more His, Trp, Tyr and perhaps Arg residues for inhibitory activity against porcine pancreatic α-amylase.  相似文献   
107.
In order to search for new active cosmetic ingredients of natural origin, we screened about 60 plants collected from Jeju Island, which is located in the southernmost part of the Republic of Korea. We investigated their free radical scavenging activity, elastase inhibition activity, and reduction of MMP-1 mRNA expression for the development of anti-aging ingredients as raw materials for use in cosmetics. In the free radical scavenging capacity assay, 12 extracts, including Typha orientalis (seed) and Torreya nucifera (leaf), showed significant free radical scavenging activity (up to SC50 < 30 μg/ml). Among these extracts, Nymphaea tetragona (rhizome) extract showed the highest free radical scavenging activity (SC50 = 4.7 μg/ml). In the anti-elastase inhibition assay, seven extracts, including T. orientalis (seed) and Persicaria hydropiper (whole plant), showed high inhibitory activity (>50% at 100 μg/ml). Among these extracts, P. hydropiper (whole plant) extract showed the highest elastase inhibition activity (IC50 = 46.7 μg/ml). In the MMP-1 expression assay using RT-PCR, T. orientalis (seed), Pyrrosia hastata (root), and Capsicum annum (whole plant) showed slightly lower inhibition activity than EGCG, which was used as a control. Furthermore, four extracts, including P. hydropiper (whole plant), Filipendula glaberrima (root), N. tetragona (root), and Camellia japonica (leaf), completely inhibited the expression of MMP-1 in human fibroblast cells. The results showed that four of the 60 plant extracts may hold potential for use as natural active ingredients for anti-aging cosmetics.  相似文献   
108.
A simple and accurate model of a permanent magnet synchronous motor (PMSM) with a light load is presented in this paper. The light-load condition is always needed in integrated circuit manufacturing machines in order to achieve a fast, accurate and minimum overshoot response. The model proposed here can help a designer to specify the controller's specifications and also to verify the hardware of motor drives. The differential equations of the PMSM are handled by the macromodels in PSPICETM. Moreover, it is revealed that the PMSM system is operating in a 4-state mode rather than a 2-state mode. Experimental results are provided to verify the simulation results of this model. The heavy load condition is also simulated.  相似文献   
109.
It is important to study an exponential-constant p-n junction because it gives a realistic approximation for many diffused p-n junction profiles. To calculate the space-charge layer capacitance for this junction we use an abrupt space-charge edge approximation with a correction which includes the effect of the mobile carriers at the edges of the space-charge region. In this approach the offset voltage voff is used in place of the built-in potential as obtained from the depletion approximation. An analytical model for the space-charge region capacitance for an exponential-constant junction is developed. This model holds well for zero bias, for small forward voltages, and for reverse voltages. It shows good agreement when compared with the Chawla-Gummel model. It is simple and gives a direct relationship between the depletion capacitance and the applied voltage.  相似文献   
110.
In this study, a rigorous methodology for quantifying recrystallization kinetics by electron backscatter diffraction is proposed in order to reduce errors associated with the operator's skill. An adaptive criterion to determine adjustable grain orientation spread depending on the recrystallization stage is proposed to better identify the recrystallized grains in the partially recrystallized microstructure. The proposed method was applied in characterizing the microstructure evolution during annealing of interstitial‐free steel cold rolled to low and high true strain levels of 0.7 and 1.6, respectively. The recrystallization kinetics determined by the proposed method was found to be consistent with the standard method of Vickers microhardness. The application of the proposed method to the overall recrystallization stages showed that it can be used for the rigorous characterization of progressive microstructure evolution, especially for the severely deformed material.  相似文献   
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