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排序方式: 共有277条查询结果,搜索用时 15 毫秒
21.
In the current study the savings of CO2 emissions due to the use of ground source heat pump (GSHP) systems was investigated in comparison to conventional heating systems. Based on a subsidy program for GSHP systems in southwest Germany, the regional, average, and total CO2 savings of 1105 installed GSHP systems were determined on a regional scale. The emitted CO2 per kWh of heating demand for the studied scenario resulted in 149 g CO2/kWh for GSHP using the German electricity mix and 65 g CO2/kWh using the regional electricity mix, which results in CO2 savings of 35% or 72%, respectively. Similar CO2 avoidances of GSHP systems were found in American and European studies ranging between 15% and 77% strongly depending on the supplied energy for the heat pumps and the efficiency of installation. The resulting CO2 savings for one installed GSHP unit in the present study therefore range between 1800 and 4000 kg per year. Nevertheless, the minimum average total annual CO2 savings of all installed GSHP systems due to the subsidy program amounted to 2000 tons per year. The maximum regional avoided additional CO2 emissions are primarily associated with the affluent suburbs of the most densely populated area in the region. In 2006 the total contribution of CO2 savings due to GSHP systems in Germany was only about 3.4% of the total renewable energies. However, continuously rising numbers of installed GSHP units and the increasing use of renewable electricity demonstrate that there is a fine opportunity to substantially avoid additional CO2 emissions associated with the provision of heating (and cooling) of buildings and other facilities. 相似文献
22.
Gisela Bockenheimer-Lucius 《Ethik in der Medizin》2002,14(2):59-59
Ohne Zusammenfassung 相似文献
23.
In this research, the authors hypothesize that affect regulation involves 2 independent strategies: affect optimization, the tendency to constrain affect to positive values, and affect complexity, the amplification of affect in the search for differentiation and objectivity. Community residents age 15 to 86 were assessed by using 2 convergent measurement domains: 1 based on measures of positive-negative affect and cognitive-affective complexity and 1 based on measures of coping and defense. Both domains yielded the hypothesized affect optimization and affect complexity dimensions. As predicted, the affect optimization dimensions are primarily related to relationship quality variables, and the affect complexity dimensions to socioeconomic status and education. Hence, positive affect and its maximization have different significance in the context of high- or low-affect complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
In Situ Scanning Electron Microscopy Observation of Growth Kinetics and Catalyst Splitting in Vapor–Liquid–Solid Growth of Nanowires
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Xing Huang Zhu‐Jun Wang Gisela Weinberg Xiang‐Min Meng Marc‐Georg Willinger 《Advanced functional materials》2015,25(37):5979-5987
In situ observations during vapor–liquid–solid (VLS) growth of semiconductor nanowires in the chamber of an environmental scanning electron microscope (ESEM) are reported. For nanowire growth, a powder mixture of CdS and ZnS is used as a source material and silver nanoparticles as a metal catalyst. Through tracing growth kinetics of nanowires, it is found that nanowires with a relatively bigger catalyst droplet on the tip grow faster. Intriguingly, it is also found that the growth of nanowires can involve catalyst splitting: while the majority of catalyst remains at the nanowire tip and continues facilitating the growth, a portion of it is removed from the tip due to the splitting. It remains attached to the nanowire at the position where the splitting occurred and subsequently induces the growth of a nanowire branch. As far as it is known, this is the first time that catalyst splitting is revealed experimentally in situ. It is proposed that the instability of catalyst droplet caused by the volume increase is the main reason for the splitting. It is believed that in situ growth inside the ESEM can largely enrich our understanding on the metal‐catalyzed VLS growth kinetics, which may open up more opportunities for morphology‐controlled synthesis of 1D semiconductor nanowires in future study. 相似文献
25.
Ecotaxes allow the internalization of costs that are considered externalities associated with polluting industrial process emissions to the atmosphere. In this paper, ecotaxes internalize polluting emissions negative impacts that are added to electricity and steam generated costs of a steam turbine and heat recovery systems from a utilities refinery plant. Steam costs were calculated by means of an exergy analysis tool and Aspen Plus simulation models. Ecotaxes were calculated for specific substances emitted in the refinery flue gases, based on a toxicity and pollution scale. Ecotaxes were generated from a model that includes damages produced to biotic and abiotic resources and considers the relative position of those substances in a toxicity and pollution scale. These ecotaxes were internalized by an exergoeconomic analysis resulting in an increase in the cost per kWh produced. This kind of ecotax is not applied in Mexico. The values of ecotaxes used in the cost determination are referred to the values currently applied by some European countries to nitrogen oxides emissions. 相似文献
26.
Andreas Guthausen Gisela Guthausen Andreas Kamlowski Harald Todt Wolfgang Burk Dieter Schmalbein 《Journal of the American Oil Chemists' Society》2004,81(8):727-731
Fat content is one of the important parameters of quality control in many food products. Several techniques are used to determine
the amount of fat in a given product. In this work, the applicability of a portable dedicated nuclear magnetic resonance (NMR)
analyzer to measure the fat content in a packaged product without destruction of the material was examined. Two different
low-field NMR methods, namely, a ratio method and a relaxation time method, were applied and discussed. The processed NMR
signal was linearly correlated with the fat content obtained by reference methods. The linear correlation allowed the application
of single-sided NMR for fat measurements.
In memoriam 相似文献
27.
28.
Gisela Epple Hope Niblick Stanley Lewis L. Dale Nolte Dan L. Campbell J. Russell Mason 《Journal of chemical ecology》1996,22(5):1013-1025
Essential oils from coniferous trees contain secondary metabolites that act as feeding deterrents for a number of herbivorous mammals. We investigated effects of pine needle oil on feeding and other behaviors of herbivorous plains pocket gophers. In experiment l, pocket gophers were offered sweet potato from single feeding stations placed in home cages of individually housed animals. Stations contained either a scent dispenser with pine needle oil or mineral oil. Subjects removed significantly less food from stations scented with pine needle oil. Experiment 2 was performed to investigate neophobic responses to odors.d-Pulegone, presented under conditions identical to those used in experiment l, did not reduce food removal compared to mineral oil. In experiment 3 pocket gophers were observed in a maze consisting of a start box connected to two goal boxes by tunnels. One goal was scented with pine needle oil, the second with mineral oil. Subjects entered goals scented with pine needle oil significantly less frequently than goals scented with mineral oil and spent less time there. They performed all recorded behaviors at lower frequencies while located in pine-scented goals. In experiment 4 animals were introduced into a maze consisting of a start box from which two soil-packed tunnels could be entered. Embedded in the soil of one tunnel was a barrier of electrical cable that had been soaked in pine needle oil, the second tunnel contained a barrier of cable soaked in mineral oil. Pocket gophers gnawed significantly less insulation from cable treated with pine needle oil than from cable treated with mineral oil. Our results show that constituents in pine needle oil are aversive to plains pocket gophers. Under natural conditions they may function as feeding deterrents. Some of the compounds may be suitable repellents for control of pocket gopher damage. 相似文献
29.
Investigated the proposition that sex role development is a life span process. It was predicted that late adolescence and adulthood would be characterized by a relative degree of relaxation of sex role specialization. At each of 3 age levels (7th grade, 12th grade, and adult) 40 male and 40 female Ss indicated on the Attitude Check List which traits they considered desirable in a male or female target ideal. Two major results were found: (a) Male and female Ss gave stereotyped responses primarily when rating an opposite-sex target, but responses were less stereotyped when judging a same-sex target figure. (b) The expected stereotype relaxation was not observed; instead, the age-related patterns primarily reflected an increased endorsement of socially desirable traits. The latter finding is in disagreement with previous research, and possible reasons for this discrepancy are explored. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
A. Seher G. Assmann Gisela Werner H. J. Oslage 《European Journal of Lipid Science and Technology》1983,85(6):215-219
Physiological Effect of Various Mixtures of Oleic, Linoleic and Linolenic Acids on Growing Pigs: 2. Influence on Depot Fats and Blood Lipids At the end of the feeding trials described extensively in the first contribution, from all animals saddle bacon and leaf fat as well as serum lipids have been investigated on effects of the various food fats. Earlier results have been confirmed according to which the increased supply of unsaturated fatty acids results in an increase of the content in depot fat and in a decrease of palmitic and stearic acid. The storage of linoleic and linolenic acids is linked to the consumed amount of these acids in a linear way. Some hints have been found for the occurrence of yellow fat desease that besides the deficiency of vitamin E an enzyme activating effect of higher amounts of linolenic acid may be responsible. Furthermore the attacked animals showed a linear dependence of the fat content in the yellow tissue from its peroxide value. As well linolenic acid as oleic acid led to a significant decrease of the serum triglycerides. Besides, linolenic acid lowered the content of serum cholesterol, whereas linoleic acid caused a significant increase of the HDL content. 相似文献