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排序方式: 共有378条查询结果,搜索用时 15 毫秒
171.
Mirchin N Apter B Lapsker I Fogel V Gorodetsky U Popescu SA Peled A Popescu-Pelin G Dorcioman G Duta L Popescu A Mihailescu IN 《Journal of nanoscience and nanotechnology》2012,12(3):2668-2671
The evanescent light photon extraction efficiency of insulator, semiconductor and conductor amorphous nanolayers deposited on glass waveguides was evaluated from Differential Evanescent Light Intensity measurements. The Differential Evanescent Light Intensity technique uses the evanescent field scattered by the deposited nanolayer, enabling nanometer thickness profiling due to the high inherent dark background contrast. The results show that the effective evanescent photon penetration depth increases from metal to semiconductor and then to insulating layers, establishing thus the effective photon-material interaction length for the various materials classes. 相似文献
172.
Lucas Fornari Laurindo Mariana Canevari de Maio Sandra Maria Barbalho Elen Landgraf Guiguer Adriano Cressoni Araújo Ricardo de Alvares Goulart Uri Adrian Prync Flato Edgar Baldi Júnior Cludia Rucco Penteado Detregiachi Jesselina Francisco dos Santos Haber Patrícia C. Santos Bueno Raul S. J. Girio Rachel Gomes Eleutrio Marcelo Dib Bechara 《International journal of molecular sciences》2022,23(11)
Rheumatoid arthritis (RA) is a systemic autoimmune disease that primarily affects the joints. Organokines can produce beneficial or harmful effects in this condition. Among RA patients, organokines have been associated with increased inflammation and cartilage degradation due to augmented cytokines and metalloproteinases production, respectively. This study aimed to perform a review to investigate the role of adipokines, osteokines, myokines, and hepatokines on RA progression. PubMed, Embase, Google Scholar, and Cochrane were searched, and 18 studies were selected, comprising more than 17,000 RA patients. Changes in the pattern of organokines secretion were identified, and these could directly or indirectly contribute to aggravating RA, promoting articular alterations, and predicting the disease activity. In addition, organokines have been implicated in higher radiographic damage, immune dysregulation, and angiogenesis. These can also act as RA potent regulators of cells proliferation, differentiation, and apoptosis, controlling osteoclasts, chondrocytes, and fibroblasts as well as immune cells chemotaxis to RA sites. Although much is already known, much more is still unknown, principally about the roles of organokines in the occurrence of RA extra-articular manifestations. 相似文献
173.
Noel D. Uri 《The International journal of environmental studies》2013,70(6):849-867
The impact of energy on the adoption of conservation tillage is of special importance in addressing concerns about the effect of agricultural production on the environment in the United States. It is the subject of this paper. After establishing that a relationship exists between the price of energy and the adoption of conservation tillage via cointegration techniques, the relationship is quantified. It is shown that while the real price of crude oil, the proxy used for the price of energy, does not affect the rate of adoption of conservation tillage, it does impact the extent to which it is used. Finally, there is no structural instability in the relationship between the relative use of conservation tillage and the real price of crude oil over the period 1963 to 1997. 相似文献
174.
Ling Ma Rafael Sacks Uri Kattel Tanya Bloch 《Computer-Aided Civil and Infrastructure Engineering》2018,33(2):152-164
Object classification is a key differentiator of building information modeling (BIM) from three‐dimensional (3D) computer‐aided design (CAD). Incorrect object classification impedes the full exploitation of BIM models. Models prepared using domain‐specific software cannot ensure correct object classification when transferred to other domains, and research on reconstruction of BIM models using spatial survey has not proved a full capability to classify objects. This research proposed an integrated approach to object classification that applied domain experts’ knowledge of shape features and pairwise relationships of 3D objects to effectively classify objects using a tailored matching algorithm. Among its contributions: the algorithms implemented for shape and spatial feature identification could process various complex 3D geometry; the method devised for compilation of the knowledge base considered both rigor and confidence of the inference; the algorithm for matching provides mathematical measurement of the object classification results. The integrated approach has been applied to classify 3D bridge objects in two models: a model prepared using incorrect object types and a model manually reconstructed using point cloud data. All these objects were successfully classified. 相似文献
175.
Uri Minzer 《Chemical engineering science》2006,61(22):7249-7259
The motivation for the present work is related to the use of parabolic trough solar power technology for direct steam generation (DSG). So far, commercial plants use liquid oil to absorb heat from the collectors, and steam is produced in heat exchangers. A more efficient process of direct steam generation in the collectors is not used due to possible uneven flow rate distribution and other instabilities, related to liquid-vapor flow in parallel pipes.In this work we present an analysis and experimental results for the flow rate distribution of water flowing and evaporating in two parallel pipes with common inlet and outlet manifolds.A new simplified model that yields the pressure drop versus the flow rate in a single pipe is developed. This model is the basis for the calculation of steady-state solutions, stability analysis and transient simulations in two parallel pipes.Multiple steady-state solutions may be obtained depending on the flow rate and the heating power. Linear stability analysis and transient simulation allow to differentiate between the stable steady states and the unstable ones. It is also shown that when few stable state solutions are possible the one that takes place depends on the history of the inlet flow rate. Experimental results compare well with the theoretical solutions. 相似文献
176.
H. Erythropel Uri Gat M. Kersten H. W. Hahnemann H. Pfeil M. Vötter 《Forschung im Ingenieurwesen》1969,35(5):167-168
Ohne Zusammenfassung
VDI 相似文献
177.
This paper introduces the special issue on information systems, identity and identification. In addition to introducing the papers in the special issue, it provides a state-of-the-art review of research into identity and identification to contextualise the contributions of the special issue papers. The paper reviews research themes in personal and organisational identity as well as research challenges in identification before considering the interplay between these two strands. 相似文献
178.
179.
Sharon Daniel Alexandrovitz Abraham Uri Joseph Ben 《Industry Applications, IEEE Transactions on》1976,(3):268-274
A new electrical transmission drive that insures an adjustable constant speed difference between a pair of mechanical shafts independent of load conditions or speed level is described in the paper. This generalized electrical shaft comprises two rotor interconnected induction machines, fed from different frequencies and two dc machines forming a double Kramer cascade. The use of the Kramer cascades offers many important advantages over the alternative simpler scheme of'using resistors in the rotor circuit, namely, higher efflciency, much lower speed dependence on load, and speed level adjustability in the subsynchronous range. The drive performance is analyzed by means of an equivalent circuit from which the current and torque expressions are derived. Good agreement is obtained between theoretical and experimental results. 相似文献
180.
Arnon Dag Eric Ben‐David Zohar Kerem Alon Ben‐Gal Ran Erel Loai Basheer Uri Yermiyahu 《Journal of the science of food and agriculture》2009,89(11):1871-1878
BACKGROUND: Macronutrients play fundamental roles in processes affecting olive oil productivity and are expected to influence oil composition. A necessary step in optimal nutrient application management for olives is an understanding of the relationship between olive tree nutritional status and oil quality parameters. We studied the independent effects of N, P and K concentrations in irrigation solution on the oil quality of ‘Barnea’ olives by applying a wide range of macronutrient concentrations under highly controlled conditions. RESULTS: Oil composition was significantly influenced by P and N levels, while K levels had only a minor effect. Unsaturation levels were unaffected by the treatments but, within the unsaturated fatty acids, the levels of PUFA increased compared to those of MUFA. Specifically, levels of the MUFA C18:1, polyphenol content and peroxide values decreased while levels of the PUFA C18:3 increased in response to higher doses of N and P. CONCLUSION: Decreased MUFA and polyphenol levels coupled with increased omega‐3 levels demonstrated a potential negative influence on oil profile alongside increased nutritional benefits. The sum effects on oil yield and composition should be considered in designing of nutrient application management strategies for olive orchards. Copyright © 2009 Society of Chemical Industry 相似文献