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141.
Offshore software development has been identified as one of the most striking manifestations of contemporary globalisation and as evidence of placelessness, the idea that information and communication technologies have rendered location irrelevant. Research in the International Business and Information Systems fields, in contrast, has suggested that all locations are not equal and has identified a number of characteristics that may influence the attractiveness of a location for multinational investment and offshoring, respectively. These literatures, however, focus almost exclusively on quantitative, economic characteristics that are seen as fixed and applying uniformly throughout a whole country. They therefore offer little guidance on the suitability of particular locations as offshoring destinations, especially in countries without a track record in offshore software development. Drawing on two cases of nearshore software development centres set up by offshore service providers in the Caribbean, this paper illustrates that, while the initial decision to establish the ventures reflected a logic of placelessness, characteristics of these particular locations affected their subsequent success. Through the findings, we therefore develop a typology of espoused, unanticipated and remediable locational characteristics, which illustrates that locational attractiveness may vary significantly within countries and that offshore service providers and government agencies can modify locational characteristics to their advantage. 相似文献
142.
Alastair A. Abbott 《Natural computing》2012,11(1):3-11
The Deutsch–Jozsa problem is one of the most basic ways to demonstrate the power of quantum computation. Consider a Boolean
function f : {0, 1}
n
→ {0, 1} and suppose we have a black-box to compute f. The Deutsch–Jozsa problem is to determine if f is constant (i.e. f(x) = const, "x ? {0,1}nf(x) = \hbox {const, } \forall x \in \{0,1\}^n) or if f is balanced (i.e. f(x) = 0 for exactly half the possible input strings x ? {0,1}nx \in \{0,1\}^n) using as few calls to the black-box computing f as is possible, assuming f is guaranteed to be constant or balanced. Classically it appears that this requires at least 2
n−1 + 1 black-box calls in the worst case, but the well known quantum solution solves the problem with probability one in exactly
one black-box call. It has been found that in some cases the algorithm can be de-quantised into an equivalent classical, deterministic
solution. We explore the ability to extend this de-quantisation to further cases, and examine with more detail when de-quantisation
is possible, both with respect to the Deutsch–Jozsa problem, as well as in more general cases. 相似文献
143.
144.
Cynthia?A?DaleyEmail author Amber?Abbott Patrick?S?Doyle Glenn?A?Nader Stephanie?Larson 《Nutrition journal》2010,9(1):10
Growing consumer interest in grass-fed beef products has raised a number of questions with regard to the perceived differences
in nutritional quality between grass-fed and grain-fed cattle. Research spanning three decades suggests that grass-based diets
can significantly improve the fatty acid (FA) composition and antioxidant content of beef, albeit with variable impacts on
overall palatability. Grass-based diets have been shown to enhance total conjugated linoleic acid (CLA) (C18:2) isomers, trans vaccenic acid (TVA) (C18:1 t11), a precursor to CLA, and omega-3 (n-3) FAs on a g/g fat basis. While the overall concentration
of total SFAs is not different between feeding regimens, grass-finished beef tends toward a higher proportion of cholesterol
neutral stearic FA (C18:0), and less cholesterol-elevating SFAs such as myristic (C14:0) and palmitic (C16:0) FAs. Several
studies suggest that grass-based diets elevate precursors for Vitamin A and E, as well as cancer fighting antioxidants such
as glutathione (GT) and superoxide dismutase (SOD) activity as compared to grain-fed contemporaries. Fat conscious consumers
will also prefer the overall lower fat content of a grass-fed beef product. However, consumers should be aware that the differences
in FA content will also give grass-fed beef a distinct grass flavor and unique cooking qualities that should be considered
when making the transition from grain-fed beef. In addition, the fat from grass-finished beef may have a yellowish appearance
from the elevated carotenoid content (precursor to Vitamin A). It is also noted that grain-fed beef consumers may achieve
similar intakes of both n-3 and CLA through the consumption of higher fat grain-fed portions. 相似文献
145.
A correlation has been developed for estimating the liquid viscosities of petroleum fractions at 100°F and at 210°F. When used with the ASTM viscosity chart (or its analytical equivalent), the new correlation provides a method for the prediction of viscosity-temperature behavior of fractions from the Watson characterization factor and specific gravity. Essentially an extension of an API Data Book viscosity nomograph, the proposed correlation substantially improves on the accuracy and increases the range of applicability of this method. Greatest accuracy is achieved for petroleum fractions in the kerosene to heavy gas oil range, although acceptable accuracy for most engineering calculations is also obtained for lube oils and for many complex pure heavy hydrocarbons. 相似文献
146.
As part of the High Average Power Laser (HAPL) program the performance of tungsten as an armor material is being studied. While the armor would be exposed to neutrons, X-rays and ions within an inertial fusion energy (IFE) power plant, the thermomechanical effects are believed to dominate. Using a pulsed X-ray source, long-term exposures of tungsten have been completed at fluences that are of interest for the IFE application. Modeling is used in conjunction with experiments on the XAPPER X-ray damage facility in an effort to recreate the effects that would be expected in an operating IFE power plant. X-ray exposures have been completed for a variety of X-ray fluences and number of shots. Analysis of the samples suggests that surface roughening has a threshold that is very close to the fluences that reproduce the peak temperatures expected in an IFE armor material. 相似文献
147.
Andrew P. Abbott Jason Griffith Cecil O'Connor Karl S. Ryder 《Surface & coatings technology》2008,202(10):2033-2039
This work demonstrates that a sustained galvanic coating of silver can be deposited onto copper substrates from a solution of Ag+ ions in an ionic liquid (IL) based on a choline chloride (ChCl) eutectic. The sustained growth of the silver deposit was facilitated by the porous nature of the film and is proven using acoustic impedance spectroscopy on a quartz crystal microbalance (QCM). The silver and copper surfaces were characterised using atomic force microscopy (AFM) and scanning electron microscopy (SEM/EDX). In the commercial process of dip coating silver from ions in aqueous media, deposition does not continue once surface coverage has been achieved, without the use of catalysts. The process reported here using ionic liquids produces silver deposits of several microns by dip coating without the use of catalysts or strong inorganic acids. 相似文献
148.
149.
150.
RE Abbott CJ Corral DM MacIvor X Lin TJ Ley TA Mustoe 《Canadian Metallurgical Quarterly》1998,133(9):1002-1006
BACKGROUND: Cathepsin G is a neutral serine proteinase that exists primarily in azurophilic granules of neutrophils, but also as a proteolytically active membrane-bound form. While the specificity and many in vitro biological activities have been described for cathepsin G, little is known about the role of this enzyme in neutrophil function in vivo, particularly as it applies to the wound-healing process. OBJECTIVE: To determine the role of cathepsin G in cutaneous tissue repair by examination of full-thickness incisional wound healing in mice with a null mutation for cathepsin G. METHODS: Paired, full-thickness linear incisions were made on the backs of cathepsin G +/+ and cathepsin G -/- mice, and wound tissue was harvested at days 1, 2, 3, 5, 7, 10, and 14 after wounding. Neutrophil influx, myeloperoxidase activity, and migration were examined using light microscopy, the myeloperoxidase assay, and modified Boyden chamber technique, respectively. Wound-breaking strength was measured using tensiometry. RESULTS: The absence of cathepsin G led to a 42% decrease in wound-breaking strength at day 7 after wounding (n=28; P<.002), which returned to the level of control mice by day 10 after wounding. Wound tissue sections in mice lacking cathepsin G also showed a 26% increase in neutrophil myeloperoxidase activity (n=12; P=.001) and an 18% increase in neutrophil influx (n=14; P=.002) at day 3 after wounding. Wound fluid collected on day 5 after wounding from cathepsin G-deficient mice attracted 58% more neutrophils than wound fluid collected from control mice (n=4; P<.05). CONCLUSIONS: Neutrophil cathepsin G is important during the early inflammatory stage of wound healing. Cathepsin G may be involved in processing 1 (or more) soluble mediator(s) in the wound milieu that is responsible for neutrophil chemotaxis. Our findings suggest that tight regulation of inflammation is necessary to prevent impaired healing during early tissue repair. 相似文献