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201.
202.
This is the second of a series of two articles, dealing with a new approach of environomic (thermodynamic, economic and environmental) performance ‘Typification’ and optimization of power generation technologies. This part treats specifically of combined heat and power (CHP) cogeneration technologies in the context of CO2 abatement and provides a methodology for a flexible and fast project based CHP system design evaluation. One of the aspect of the approach is the post-optimization integration of the operating and capital costs, in order to effectively deal with the uncertainty of the project specific design and operation conditions (fuel, electricity and heat selling prices, project financial conditions such as investment amortization periods, annual operating hours, etc). In addition the approach also allows to efficiently evaluate the influence of the external cost such as the CO2 tax level under a tax scheme or the CO2 permit price in the emission trading market. 相似文献
203.
Yvonne G. J. van Helden Roger W. L. Godschalk Johannes von Lintig Georg Lietz Jean‐Francois Landrier M. Luisa Bonet Frederik J. van Schooten Jaap Keijer 《Molecular nutrition & food research》2011,55(10):1466-1474
Scope: Little information is available on differences, commonalities and especially interactions in overall gene expression responses as a result of diet, differences in sex (male and female) and effects induced by differences in metabolism. Moreover, it is unknown whether such effects are tissue specific. Methods and results: We investigated the gene expression effects induced by β‐carotene (BC) supplementation, knockout of β‐carotene 15,15′‐monooxygenase 1 (Bcmo1) and differences between male and female mice in lung, liver and inguinal white adipose tissue (iWAT). Unsupervised principal component analysis showed that lung gene expression was most affected by knockout of Bcmo1. Liver was most affected by knockout of Bcmo1 and differences in sex. iWAT was most affected by differences in sex. Hardly any genes were commonly influenced by BC among the three tissues. The effect of BC supplementation and knockout of Bcmo1 were relatively sex specific, especially in iWAT. Conclusion: These data demonstrate that gene expression differences induced by BC are limited to the tissue and sex that is analyzed, and that differences in metabolism induced by for example single nucleotide polymorphisms, should be taken into account as much as possible. Moreover, our results indicate that translation from one tissue to the other should be done with caution for any nutritional intervention. 相似文献
204.
Kuanysh B. Isbekov Vyacheslav N. Tsoy Jean‐Francois Crtaux Nikolai V. Aladin Igor S. Plotnikov Guillaume Clos Muriel Berge‐Nguyen Saule Zh. Assylbekova 《Lakes & Reservoirs: Research and Management》2019,24(2):195-208
The water level variations of the Lake Balkhash, the Kapshagay Reservoir and the Ili River and the linkage with salinity and biological conditions are investigated in this work using different techniques: satellite radar altimetry, in situ gauges, historical archives of fish population counting and field works. We show that it is possible now to monitor, over decades, in near real time, with high precision, the water level changes in the Lake Balkhash from satellite altimetry, over the reservoir and also along the Ili River. The vulnerability of the lake fauna and flora populations is enhanced by the morphometry of the lake: shallow and separation of the eastern basin from the western basin through the narrow Uzun‐Aral strait. Water policy of the Ili River also plays a fundamental role in the evolution of the Balkhash Lake. The Ili River that provides 80% of the surface water of the lake is a transboundary river. Development of intense irrigated agriculture in the upstream part of this river, located in the Chinese territory, could lead in the future to high hydrological stress in the downstream regions with potentially high damage in the delta and for fishery production. We show here the recent evolution of the Lake Balkhash basin from satellite data. Some interannual oscillation of 6–8 years over the last decade has been highlighted, with a water level of the lake still at a high value, but prediction on increasing irrigation is also highlighting the vulnerability of this lake. Linkage between water level change along the river and the downstream waters is also investigated. It shows that the role of the reservoir is not fundamental in the understanding of the Lake Balkhash water level changes which is in contrast highly correlated to upstream river level changes. 相似文献
205.
A method is described for the rational selection of metal oxide varistors as surge protective devices in low-voltage applications, combining data on the surge environment and device characteristics. Fuses that may be connected in series with the varistors will be exposed to current surges resulting from the varistor operation. Experimental results on the effect of repetitive current surges on such fuses are described, and some guidance is provided on the necessary derating of fuses for series applications with varistors. 相似文献
206.
207.
We have determined the complete nucleotide sequence of a 44 420 bp DNA fragment from chromosome XIV of Saccharomyces cerevisiae. The sequence data revealed 23 open reading frames (ORFs) larger than 300 bp, covering 73·5% of the sequence. The ORFs N2418, N2441, N2474 and N2480 correspond to previously sequenced S. cerevisiae genes coding respectively for the mitochondrial import protein Mas5, the nucleolar protein Nop2, the outer mitochondrial membrane porin Por1, the cytochrome c oxidase polypeptide VA precursor CoxA and the yeast protein tyrosine phosphatase Msg5. Translation products of three other ORFs N2406, N2411 and N2430 exhibit similarity to previously known S. cerevisiae proteins: the ribosomal protein YL9A, the protein Nca3 involved in the mitochondrial expression of subunits 6 and 8 of the ATP synthase and actin; in addition N2505 presents strong similarity to an ORF of chromosome IX. The predicted protein products of ORFs N2417 and N2403 present similarities with domains from proteins of other organisms: the Candida maltosa cycloheximide-resistance protein, the human interleukin enhancer-binding factor (ILF-2). The 12 remaining ORFs show no significant similarity to known proteins. In addition, we have detected a DNA region very similar to the yeast transposon Ty 1–15 of which insertion has disrupted a tRNAAsp gene. The sequence has been deposited in the GenBank database with the Accession Number U12141. 相似文献
208.
Siku Makani Maryvonne Brigodiot Ernest MarChal Jean-Pierre Durand Francois Dawans 《应用聚合物科学杂志》1984,29(12):4091-4106
The synthesis of ethyl-11-aminoundecanoate and ethyl-3-aminobutyrate and the chemical modification of chlorinated natural rubber by these amino–esters were investigated in order to find useful materials for long-life antifouling paints free from toxic moieties. Detailed reactions and fractionation schemes are described for isolating pure products; their structure was characterized by IR and NMR spectrometries. 相似文献
209.
The purpose of this in vitro study was to determine the relationship between the shear bond strength [SBS] of seven dentin bonding systems to dentin and the quantitative microleakage [ML] of Class V preparations in dentin restored with these systems. The systems evaluated were All-Bond/Bisfil-P [A]; Syntac/Heliomolar [B]; XR-Bond/Herculite [C]; Scotchbond 2/Silux [D]; Denthesive/Charisma [E]; Prisma Universal Bond 2/Prisma AP.H [F]; and Tenure/Perfection [G]. The 115 specimens were removed from the assembly apparatus and stored in saline at 37 degrees C for 24 hours, the SBS determined and expressed in MPa. Fifteen Class V preparations in dentin were restored with each of the bonding systems, thermocycled 500x in 2% methylene blue solution between 50 degrees C and 8 degrees C, and the ML determined by means of a spectrophotometric dye-recovery method. The ML was expressed in microgram dye/restoration. The data were analyzed by ANOVA, Student-Newman-Keuls test, and linear regression analysis. The SBS in MPa were: A:17.2 +/- 3.6; B:15.9 +/- 2.1; C:15.4 +/- 3.7; D:11.6 +/- 2.2; E:10.7 +/- 3.7; F:10.4 +/- 2.5; G:8.2 +/- 3.9. The ML in microgram dye/restoration were: A:2.6 +/- 1.2; B:2.6 +/- 1.0; C:2.2 +/- 1.9; D:3.1 +/- 2.9; E:4.6 +/- 4.2; F:2.6 +/- 2.5; G:4.4 +/- 4.1. SBS = 20.91-2.60 [microgram dye]. The results suggest that a SBS of +/- 21 MPa may reduce ML to near zero. 相似文献
210.
自从上世纪60年代第一种心脏起搏器出现以来,超低功耗(Ultra-LowPower,ULP)性能就成了医用电子行业关心的一件头等大事。对长电池寿命和超微型化的需求,已经促成了功耗极低的系统的出现,它们的功耗比常用的低功耗手持消费类产品,如手机、PDA(个人数字助理)还要低得多。举例来说,一种双室心脏起搏器的功耗不到10mW(4mA×2.5V),依靠一个电池就可以工作7年以上,其外形大小只有8立方厘米,重量不到18克(参见图1)。一种耳道完全内藏式(completely-in-the-canal)助听器只需1.25V的电源提供900mA的电流,即可保证助听器中所有模拟、数字电路和… 相似文献