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排序方式: 共有1392条查询结果,搜索用时 31 毫秒
1.
Rodríguez-Pérez Ángel Mariano Pérez-Calañas Cinta Pulido-Calvo Inmaculada 《Water Resources Management》2021,35(6):1977-1990
Water Resources Management - This paper aims to evaluate the possibility of using non-utilized hydraulic energy in urban water distribution systems. For this purpose, the viability and possible... 相似文献
2.
Carcinoma of the prostate, that is adenocarcinoma, is one of the most common malignancies in the male with an estimated incidence for 1991 of 122,000 new cases. On the other hand, squamous cell carcinoma of the prostate, with a median incidence of .5%-1% of all prostatic malignancies, has a similar clinical presentation but differs in treatment response and prognosis. We herein present one case of this histological pattern and review the literature pertaining to it. 相似文献
3.
The thermal evolution of defects produced by ion irradiation is studied by kinetic Monte Carlo and Rate Theory approaches. An isochronal annealing is simulated to evidence the different thermally activated mechanisms that govern defect evolution. KMC simulations show that in the case of ion irradiation, additional recovery peaks should be expected, in comparison to electron irradiation conditions. A comparison between kMC and RT results indicates that some of these peaks are due to spatially – correlated recombinations that occur at low temperature. Therefore kMC and RT approaches differ at low temperature. However, at higher temperature results obtained by both models are in near perfect agreement. In addition, we studied the influence of vacancy cluster mobility on the evolution of damage. KMC simulations show that the mobility of V2, V3 and V4 clusters does not significantly affect the evolution of defects and can be neglected in these conditions. 相似文献
4.
A population from a Central Spanish region (Tormes-Alberche Valley) has been investigated for the presence of red-green colour vision defects. A sample of 998 subjects (469 male and 529 female) was analyzed. To identify colour vision defects, Ishihara test plates were used. The red-green colour blindness percentage obtained was 4.69 +/- 0.976% for males (2.13% protan and 2.56% deutan types) and none of the females tested were found to be colour blind. These results are within the variation range of Mediterranean populations and lower than the usual frequencies among non-Mediterranean European samples. 相似文献
5.
A.B. Dalton A. Ortiz‐Acevedo V. Zorbas E. Brunner W.M. Sampson S. Collins J.M. Razal M. MikiYoshida R.H. Baughman R.K. Draper I.H. Musselman M. Jose‐Yacaman G.R. Dieckmann 《Advanced functional materials》2004,14(12):1147-1151
Numerous applications, from molecular electronics to super‐strong composites, have been suggested for carbon nanotubes. Despite this promise, difficulty in assembling raw carbon nanotubes into functional structures is a deterrent for applications. In contrast, biological materials have evolved to self‐assemble, and the lessons of their self‐assembly can be applied to synthetic materials such as carbon nanotubes. Here we show that single‐walled carbon nanotubes, coated with a designed amphiphilic peptide, can be assembled into ordered hierarchical structures. This novel methodology offers a new route for controlling the physical properties of nanotube systems at all length scales from the nano‐ to the macroscale. Moreover, this technique is not limited to assembling carbon nanotubes, and could be modified to serve as a general procedure for controllably assembling other nanostructures into functional materials. 相似文献
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7.
Merino Gonzalez J.L. Ortiz Saenz F. Valencia Miranda G. 《Solid-State Circuits, IEEE Journal of》1991,26(9):1270-1277
The shumbler (shuffler/scrambler) is a circuit designed and fabricated to form part of a broadband customer premises network. The circuit is implemented in 1.2-μm BiCMOS double-metal technology. The circuit is bidirectional, and can perform the functions of scrambling and shuffling or descrambling and unshuffling by means of control signals to three integrated multiplexers. The shumbler also includes a programmable multiplexer that allows the selection of one out of the 16 output channels of the shuffler through a serial output for local system test purposes. The shumbler circuit interfaces emitter-coupled-logic (ECL) and transistor-transistor-logic (TTL) logic levels using a single power supply of -5 V, dissipating 1.5 W, and encapsulated in a 68-pin LCC package with a flat heat spreader which ensures a thermal resistivity of about 10°C/W 相似文献
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This essay describes the domain of research in communication law and policy. It is based on a content analysis of research published in the journal Communication Law and Policy (1996–2004), papers presented to the Communication Law and Policy Division at annual conferences of the International Communication Association (1997–2004), as well as consideration of other resources. The most frequent areas for research were media regulation, Internet policy, and freedom of expression issues. After reviewing recent literature on the first two topics, we identified and showcased two emergent categories deserving future attention: communication and the law (particularly fair trial-free press issues) and implications of the burgeoning consolidation of media ownership. 相似文献
10.
Jaime Ortiz Óscar Palma Natalia González Santiago P. Aubourg 《European Journal of Lipid Science and Technology》2008,110(12):1127-1135
The flow ice system including ozone (OFI condition) was tested for slaughtering and storage (up to 16 days) of farmed rainbow trout (Oncorhynchus mykiss). Lipid damage analyses were carried out and compared to sensory acceptance and instrumental colour changes. Comparison to individuals processed with the flow ice system in the absence of ozone (FI condition) was undertaken. Rainbow trout slaughtered and chilled under FI and OFI conditions showed a low lipid damage development, according to lipid oxidation and hydrolysis events and lipid composition (polyunsaturated fatty acids, phospholipids and endogenous antioxidants) changes. Additionally, both icing conditions led to largely good quality and shelf life times and to the absence of changes in colour properties. It is concluded that flow ice as such, or including the presence of ozone, can be considered as ideal strategy to be employed as slaughtering and storage system during the commercialisation of the actual farmed species. The ozone presence has shown some profitable effects as leading to an extended shelf life time by quality retention of several sensory parameters; in contrast, some negligible negative effects could be observed on the secondary and tertiary lipid oxidation development. However, the oxidation values reached by individuals kept under OFI conditions cannot be considered as particularly high. 相似文献