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排序方式: 共有1933条查询结果,搜索用时 19 毫秒
61.
Shiro Nishiwaki Andreas Burn Stephan Buecheler Martin Muralt Snke Pilz Valerio Romano Reiner Witte Lukas Krainer Gabriel J. Spühler Ayodhya N. Tiwari 《Progress in Photovoltaics: Research and Applications》2015,23(12):1908-1915
Monolithically integrated Cu(In,Ga)Se2 mini‐modules were fabricated in order to reduce the width of patterning related dead area. The Cu(In,Ga)Se2 layers were prepared on soda‐lime glasses using the multistage process at low substrate temperature below 500 °C. A picosecond laser with a wavelength of 532 nm was used for all of the structuring processes (P1, P2, and P3) for the monolithic integration. A “lift‐off” type structuring was applied for P1 and P3, and an “ablation” type was for P2. The laser structuring was optimized to be minimizing the dead area width, and the width of about 70 µm was successfully achieved. A mini‐module, in which the optimized structuring processes were applied for the integration, demonstrated a certified efficiency of 16.6%. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
62.
Several neotropical leaf-beetles of the genus Platyphora ingest and specifically metabolize plant acquired pyrrolizidine alkaloids (PAs) of the lycopsamine type (e.g., rinderine or intermedine) and enrich the processed alkaloids in their exocrine defensive secretions. In contrast to the related palaearctic leaf beetles of the genus Oreina, which absorb and store only the non-toxic alkaloid N-oxides, Platyphora sequesters PAs exclusively as protoxic tertiary amines. In this study, the ability of P. boucardi larvae to accumulate PAs was investigated. Tracer studies with [14C]rinderine and its N-oxide revealed that P. boucardi larvae, like adult beetles, utilize the two alkaloidal forms with the same efficiency, but accumulate the alkaloid as a tertiary amine exclusively. Ingested rinderine is rapidly epimerized to intermedine, which is localized in the hemolymph and all other tissues; it is also detected on the larval surface. Like adults, larvae are able to synthesize their own alkaloid esters (beetle PAs) from orally administered [14C]retronecine and endogenous aliphatic 2-hydroxy acids. These retronecine esters show the same tissue distribution as intermedine. A long-term feeding experiment lasting for almost four months revealed that retronecine esters synthesized from [14C]retronecine in the larvae are transferred from larvae via pupae into the exocrine glands of adult beetles. Pupae contain ca. 45% of the labeled retronecine originally ingested, metabolized, and stored by larvae; ca. 12% of larval radioactivity could be recovered from the defensive secretions of adults sampled successively over two and a half months. Almost all of this radioactivity is found in the insect-made retronecine esters that are highly enriched in the defensive secretions, i.e., more than 200-fold higher concentration compared to pupae. 相似文献
63.
Kristof De Witte Rui C. Marques 《International Transactions in Operational Research》2009,16(2):257-271
Environmental factors add complexity to the comparison between specific activities or entire entities. Decision making units with an inferior performance are tempted to invoke that their organization is "different" from the others in the data set. By reinterpreting and extending the metafrontier literature, we propose an all-embracing concept to fully capture the operational environment. We suggest the "Group Specific Technical Efficiency" as a new measure to assess the overall efficiency of a utility while allowing for environmental differences. A real-world example of drinking water utilities from five different countries illustrates the concept. 相似文献
64.
65.
This paper addresses the problem of training trajectories by means of continuous recurrent neural networks whose feedforward parts are multilayer perceptrons. Such networks can approximate a general nonlinear dynamic system with arbitrary accuracy. The learning process is transformed into an optimal control framework where the weights are the controls to be determined. A training algorithm based upon a variational formulation of Pontryagin's maximum principle is proposed for such networks. Computer examples demonstrating the efficiency of the given approach are also presented. 相似文献
66.
Harmonic measurements, analysis, and power factor correction in amodern steel manufacturing facility
Maximizing electric power transfer directly affects the productivity of an electric arc furnace operation. Arc furnaces and rolling mill loads operate at power factors that result in penalty charges and lower bus voltages. In addition, the nonlinear characteristics of the furnace arcs and rolling mill drives generate significant harmonic currents that flow through the plant and utility power system. These harmonic currents cause system voltage distortion and power loss in the system, and can interact with power factor correction capacitor banks leading to equipment failures. This paper presents the analytical technique used to correct power factor in a modern steel manufacturing facility. The study included field measurements, harmonic analysis, and filter design work to reduce the amount of harmonic distortion in the plant. The modeling of arc furnaces and rolling mills for a harmonic analysis study is also discussed. The solutions recommended in this paper to increase power factor and reduce harmonics can be applied to other steel manufacturing facilities to improve power quality and therefore plant productivity 相似文献
67.
68.
MB Mihailovi? DM Avramovi? IB Jovanovi? OJ Pesut DP Mati? VJ Stojanov 《Canadian Metallurgical Quarterly》1998,17(3-4):285-289
Among the 57 monoclonal antibodies analyzed within the T-cell group of the Second International Swine CD Workshop, one mAb fell within cluster T14a that included the CD6 standard a38b2 (No. 175). The new mAb MIL8 (No. 082) and a38b2 both precipitated from activated T-cells a 150 kDa monomeric protein. Staining patterns on the various cell types were similar. There was no inhibition of binding of either mAb to peripheral blood T-cells with the opposite mAb. The new mAb, MIL8, reacts with a separate epitope on porcine wCD6. 相似文献
69.
To assess the effects of normal aging and senile dementia of the Alzheimer's type (SDAT) on semantic analysis of words, we examined the N400 component of the event-related potential (ERP) elicited during the processing of highly constrained (opposites) and less constrained materials (category-category exemplars) in 12 young control subjects, 12 elderly control subjects and 12 patients with SDAT. We employed a priming paradigm in which a context phrase was spoken and a target word (congruent or incongruent) was presented visually. The N400 effect was reduced in amplitude and delayed in the elderly control group relative to that of the younger subjects, and was further attenuated in amplitude, delayed in latency and somewhat flatter in its distribution across the scalp in the SDAT patients. These findings are consistent with less efficient processing and integration of lexical items with semantic context in normal aging, which is further exacerbated by SDAT. Differences in the N400 range associated with the opposite and category conditions were observed only in the young subjects, suggesting less use of controlled attentional resources or perhaps weaker associative links with age. 相似文献
70.
BACKGROUND & AIMS: Intestinal smooth muscle cells (ISMCs) express major histocompatibility complex II (MCH II) and intercellular adhesion molecule 1 (ICAM-1) after exposure to interferon gamma (IFN-gamma). T lymphocytes invade the intestinal musculature during Crohn's disease or pseudoobstruction. The aim of this study was to determine whether ISMCs activate syngeneic T cells via MHC II and ICAM-1. METHODS: Cultured murine ISMCs were exposed to IFN-gamma for 72 hours and analyzed for Mac-1 (CD11B CD18) antigen, MHC II, and ICAM-1 expression using enzyme-linked immunosorbent assay and fluorescence-activated cell sorter scan. T lymphocytes from mesenteric lymph nodes of ovalbumin-sensitized mice were examined for their ability to proliferate after coculture with IFN-gamma-pretreated and ovalbumin-pretreated ISMCs using [3H]thymidine incorporation. RESULTS: ISMCs expressed smooth muscle alpha-actin before and after IFN-gamma exposure. No macrophages were identified in these cultures. Exposure to IFN-gamma and ovalbumin for 72 hours induced MHC II and ICAM-1 expression; these treated ISMCs induced T-cell proliferation, whereas untreated ISMCs did not. T-cell proliferation was markedly enhanced by adding interleukin 2 and was blocked by antibodies against MHC II and ICAM-1. CONCLUSIONS: ISMCs activate T lymphocytes in an MHC II-linked manner and thus possess the ability to modulate immune function in the gut. 相似文献