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1.
The vicissitudes of the Israeli-Palestinian peace process since 1967 are analyzed using attitudes and related concepts where relevant. The 1967 war returned the two peoples' zero-sum conflict around national identity to its origin as a conflict within the land both peoples claim. Gradually, new attitudes evolved regarding the necessity and possibility of negotiations toward a two-state solution based on mutual recognition, which became the building stones of the 1993 Oslo agreement. Lacking a commitment to a final outcome, the Oslo-based peace process was hampered by reserve options, which increased avoidance at the expense of approach tendencies as the parties moved toward a final agreement. The resulting breakdown of the process in 2000 produced clashing narratives, reflecting different anchors for judgment and classical mirror images. Public support for violence increased, even as public opinion continued to favor a negotiated two-state solution. Reviving the peace process requires mutual reassurance about the availability of a partner for negotiating a principled peace based on a historic compromise that meets the basic needs and validates the identities of both peoples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The application of transcranial Doppler (TCD) ultrasonography to asymptomatic prosthetic heart valve patients can result in detection of localized bursts of high intensity signals, similar to those caused by the passage of emboli. The origin of these signals is not known. In order to investigate this phenomenon in a simplified, more controllable environment, a TCD machine was used to record flow downstream from mechanical prosthetic heart valves in a mock circulatory loop. The model, which uses a saline solution seeded with silk particles (< 15 micrometers) as the circulatory fluid, recreates the principal hydrodynamic characteristics of the left heart and systemic circulation. Reproducibility of the system was established through repeated testing of a Monostrut valve. Three different mechanical valve types, (Monostrut, Medtronic Hall, St. Jude Medical) were tested over a range of simulated cardiac outputs, and the effect of valve size was investigated with four Omniscience tilting disc valves (21, 23, 25 and 29 mm). Average energy of the reflected Doppler signal was used to quantify the amount of high intensity Doppler signal, QTCD. TCD signals recorded in vitro were visually and aurally similar to those found in prosthetic heart valve patients. All valve types generated exponentially more QTCD with increasing simulated cardiac output. Differences amongst valve types were only significant at higher flow outputs, with the Monostrut valve producing the greatest QTCD. Larger valves consistently generated greater QTCD than smaller valves. In conclusion, TCD signals found in prosthetic heart valve patients can be reproduced, at least qualitatively, using a mock circulatory loop which does not incorporate the formed elements of blood.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Escherichia coli DNA polymerase III holoenzyme contains 10 different subunits which assort into three functional components: a core catalytic unit containing DNA polymerase activity, the beta sliding clamp that encircles DNA for processive replication, and a multisubunit clamp loader apparatus called gamma complex that uses ATP to assemble the beta clamp onto DNA. We examine here the function of the psi subunit of the gamma complex clamp loader. Omission of psi from the holoenzyme prevents contact with single-stranded DNA-binding protein (SSB) and lowers the efficiency of clamp loading and chain elongation under conditions of elevated salt. We also show that the product of a classic point mutant of SSB, SSB-113, lacks strong affinity for psi and is defective in promoting clamp loading and processive replication at elevated ionic strength. SSB-113 carries a single amino acid replacement at the penultimate residue of the C-terminus, indicating the C-terminus as a site of interaction with psi. Indeed, a peptide of the 15 C-terminal residues of SSB is sufficient to bind to psi. These results establish a role for the psi subunit in contacting SSB, thus enhancing the clamp loading and processivity of synthesis of the holoenzyme, presumably by helping to localize the holoenzyme to sites of SSB-coated ssDNA.  相似文献   
4.
The firm energy of generation plants is a critical component in some electricity markets. It is usually calculated by the regulator and sets a cap to the amount a plant can trade in capacity markets (or auctions), in order to avoid free-riding behaviors. Firm energy is a systemic property and, in case of hydro plants, a synergy is observed whenever a cooperative operation occurs, i.e., the firm energy of a system is greater than the sum of the individual plants. This immediately raises the question of how to divide the system's firm energy among the individual hydro plants. The objective of this work is to investigate the application of different allocation methods of firm energy rights among hydro plants using a game-theoretic framework. It is shown that there is not an optimal and unique approach to make this allocation. The paper investigates the advantages and disadvantages of different methods, such as marginal allocation, average production during the critical period, incremental allocation, finally recommending the Aumann-Shapley as the allocation method. This method is tested for the Brazilian power system, which has around 100 hydro plants. The results obtained are compared with the current allocation adopted by the electricity regulatory agency of Brazil.  相似文献   
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Replicative DNA polymerases are multiprotein machines that are tethered to DNA during chain extension by sliding clamp proteins. The clamps are designed to encircle DNA completely, and they are manipulated rapidly onto DNA by the ATP-dependent activity of a clamp loader. We outline the detailed mechanism of gamma complex, a five-protein clamp loader that is part of the Escherichia coli replicase, DNA polymerase III holoenzyme. The gamma complex uses ATP to open the beta clamp and assemble it onto DNA. Surprisingly, ATP is not needed for gamma complex to crack open the beta clamp. The function of ATP is to regulate the activity of one subunit, delta, which opens the clamp simply by binding to it. The delta' subunit acts as a modulator of the interaction between delta and beta. On binding ATP, the gamma complex is activated such that the delta' subunit permits delta to bind beta and crack open the ring at one interface. The clamp loader-open clamp protein complex is now ready for an encounter with primed DNA to complete assembly of the clamp around DNA. Interaction with DNA stimulates ATP hydrolysis which ejects the gamma complex from DNA, leaving the ring to close around the duplex.  相似文献   
7.
Administrative and regulatory authorities, politicians, utilities and consumers have tried to understand the underlying reasons for the crisis and extract pertinent lessons for Spain. The Spanish situation following the California crisis, as well as the major topics, are examined in this article. Significant similarities and differences with the Spanish system are evaluated.  相似文献   
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9.
Solutions to dual trigonometric series are frequently given as double singular integrals, which are not conducive to automatic numerical evaluation. It is suggested that by performing a preliminary Fourier analysis on the data, the double singular integrals can be eliminated, and the solutions reduced to a finite number of precisely specified elementary arithmetic operations. This technique is used to reduce to an algorithm the analytic solution to a dual cosine series which had earlier been derived by the method of orthogonality relations. Some computational results are also presented.  相似文献   
10.
Near-infrared reflectance spectroscopy (NIRS) was used to develop equations to predict condensed tannins (CT) in greater lotus (Lotus uliginosus Schkuhr) with a precision satisfactory for the screening of genotypes in a plant breeding programme. NIRS equations were developed using both partial least squares and stepwise multiple linear regression techniques, and a wide range of mathematical treatments of the log 1/reflectance NIRS data. In general, equations developed using partial least squares regression techniques had 10–15% lower standard errors than those developed using stepwise multiple linear regression, during both calibration and prediction. Standard errors of calibration ranged from 10 to 17 g kg−1, standard errors of prediction from 12 to 17 g kg−1. These errors equate to coefficients of variation in the order of 20% The use of NIRS to predict CT in greater lotus will allow more rapid evaluation and selection of genotypes than could be achieved using butan-1-ol/HCl hydrolysis. © 1997 SCI.  相似文献   
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