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131.
132.
In this article a numerical investigation of a connecting rod bearing operating at 6,500 rpm is performed. This is a companion to an earlier article that took into account the effects of the inertial force and the variable bolt tension force, which are considered to be the principal factors that affect the connecting rod bearing lubrication characteristics of an engine running at high speed. It was found that a thinner minimum oil film and a larger peak hydrodynamic pressure are predicted in a deformed connecting rod bearing than in a rigid connecting rod bearing. Multi-peaked hydrodynamic pressure was found to appear as well because of two or more converging-diverging film regions. 相似文献
133.
Nathan H Vande Burgt Florence Abram Gerald Barry Owen Fenton Bryan K Markey Stephen Nolan Karl Richards Declan Bolton Theo De Waal Stephen V Gordon Vincent O'Flaherty Paul Whyte Annetta Zintl 《Journal of the science of food and agriculture》2017,97(3):719-723
The process of anaerobic digestion (AD) is valued as a carbon‐neutral energy source, while simultaneously treating organic waste, making it safer for disposal or use as a fertilizer on agricultural land. The AD process in many European nations, such as Germany, has grown from use of small, localized digesters to the operation of large‐scale treatment facilities, which contribute significantly to national renewable energy quotas. However, these large AD plants are costly to run and demand intensive farming of energy crops for feedstock. Current policy in Germany has transitioned to support funding for smaller digesters, while also limiting the use of energy crops. AD within Ireland, as a new technology, is affected by ambiguous governmental policies concerning waste and energy. A clear governmental strategy supporting on‐site AD processing of agricultural waste will significantly reduce Ireland's carbon footprint, improve the safety and bioavailability of agricultural waste, and provide an indigenous renewable energy source. © 2016 Society of Chemical Industry 相似文献
134.
McCormick JM Van Es T Cooper KR White LA Häggblom MM 《Environmental science & technology》2011,45(15):6567-6574
Bisphenol A (BPA) is used in the manufacture of plastics, and has been identified in various environmental matrices, including human serum and breast milk. The prevalence of BPA in the environment and the potential exposure to humans underscores the need to more fully understand the fate of BPA in the environment and the resulting effects and toxicity to humans and other organisms. Here we demonstrate that Mycobacterium species, including Mycobacterium vanbaalenii strain PYR-1, are able to O-methylate BPA to its mono- and dimethyl ether derivatives (BPA MME and BPA DME, respectively). The O-methylation of BPA results in metabolites with increased toxicity as shown from differences in survival and occurrence of developmental lesions in developing zebrafish embryos exposed to BPA, BPA MME, and BPA DME. The mono- and dimethyl ether derivatives were more toxic than BPA, resulting in increased mortality at 5 (LC(50) = 0.66 and 1.2 mg L(-1)) and 28 (LC(50) = 0.38, <0.5 mg L(-1)) days post fertilization. Furthermore, exposure to either of the O-methylated metabolites resulted in an increase in the incidence of developmental lesions as compared to BPA exposure. These data illustrate a new mechanism for microbial transformation of BPA, producing metabolites warranting further study to understand their prevalence and effects in the environment. 相似文献
135.
Background
Tobacco smoking is the leading preventable cause of morbidity and mortality in Australia and other developed countries. Of the pharmacological aids that are available for smoking cessation, bupropion (Zyban SR) is eligible for public reimbursement on the Australian Pharmaceutical Benefits Scheme (PBS), whereas nicotine replacement therapy (NRT) is not. Information on the cost‐effectiveness and financial impact of public reimbursement of these strategies can better inform debate about their inclusion or exclusion in public reimbursement schemes.Objective
To estimate the cost‐effectiveness of bupropion and NRT, and the potential financial impact of public reimbursement of NRT in Australia.Design
A cost‐effectiveness analysis using a deterministic Markov model, and cost per disability‐adjusted life year (DALY) averted over a lifetime as the outcome measure.Population
Current smokers, motivated to quit, in Australia in 2000.Interventions
(1) NRT; (2) bupropion; and (3) a combined strategy using bupropion as the first‐line treatment and NRT in those who fail to quit smoking or have adverse reactions to bupropion.Results
Quitting smoking can increase life expectancy of current smokers by 1–7.6 years depending on age at cessation and sex. Providing bupropion to current smokers who are motivated to quit would cost A$7900 (95% uncertainty interval A$6000 to A$10 500) for each DALY averted; NRT patches would cost A$17 000 (A$9000 to A$28 000) for each DALY averted, with similar results even if used as a second‐line treatment following initial failure to quit using bupropion. If 6% of current smokers were to use NRT following inclusion on the PBS, this would result in an annual cost of A$40–110 million to the PBS depending on the listed price.Conclusions
Compared with other drugs included on the PBS, bupropion and NRT are both highly cost‐effective smoking cessation interventions, and including NRT on the PBS would have a moderate financial impact. Given the sizeable health burden of smoking, and the large individual benefits of quitting smoking, increasing the availability of alternative aids and uptake of these strategies through public reimbursement would be a positive and rational step towards further reducing tobacco‐related disease burden in Australia and other countries where NRT is currently not subsidised.Tobacco smoking is the largest preventable cause of morbidity and mortality in Australia and other developed countries. Despite projected declines in tobacco‐related diseases in line with decreasing prevalence, tobacco is still expected to be among the leading causes of disease burden in 2016.1 Worldwide, it is the second highest cause of death and fourth highest cause of disease burden.Effective policies to control tobacco use are crucial. Although preventing individuals from starting smoking is an important aim of tobacco control, cessation in current smokers is also critical. As nicotine is highly addictive, smokers often require assistance to maintain abstinence. Modestly effective cessation aids are available, including pharmacological agents, such as bupropion (Zyban SR) and nicotine replacement therapy (NRT).2,3Australia has implemented many strong tobacco control policies. The retail price of tobacco in Australia is among the top three worldwide.4 Advertising and promoting tobacco products has been totally banned, pictorial pack warnings have recently been implemented, opportunities to smoke cigarettes in public places are severely limited and there is legislation in place forcing an upcoming ban of smoking in bars and hotels.5,6,7 Despite these measures, nearly one in five Australian adults still smoke daily, indicating the need for further strategies to encourage cessation.8In 1995, the Australian government rejected a recommendation by the Pharmaceutical Benefits Advisory Committee to include NRT on the public reimbursement scheme—the Pharmaceutical Benefits Scheme (PBS).9 By contrast, bupropion was made available on the PBS in February 2001.10 The continued exclusion of NRT and inclusion of bupropion may or may not be a rational decision. Valid and comparable information on the cost‐effectiveness and financial implications of including these interventions on the PBS are important inputs into this debate.The cost‐effectiveness of both NRT and bupropion has been studied previously.2 A lack of consistency in the methods of these studies, however, makes comparisons difficult, and the context‐specific nature of inputs into cost‐effectiveness analyses such as disease outcomes means that these results may not be applicable to the Australian setting.2,11 This study aims to evaluate the cost‐effectiveness of NRT and bupropion in the Australian context, as well as the potential financial impact of including NRT on the PBS. 相似文献136.
137.
Bernd Wondergem Patrick van Bommel Theo van der Weide 《Knowledge and Information Systems》2000,2(1):33-52
In this article, a formalisation of index expressions is presented. Index expressions are more expressive than keywords while
maintaining a comprehensible complexity. Index expressions are well-known in Information Retrieval (IR), where they are used
for characterising document contents, formulation of user interests, and matching mechanisms. In addition, index expressions
have found both practical and theoretical applicability in 2-level hypermedia systems for IR. In these applications, properties
of (the structure of) index expressions are heavily relied upon. However, the presupposed mathematical formalisation of index
expressions and their properties still lacks. Our formalism is based on the structural notation of index expressions. It is
complete in the sense that several notions of subexpressions and defoliation of index expressions are also formalised. Defoliation,
which plays an important role in defining properties of index expressions, is provided as a recursively defined operator.
Finally, two other representational formalisms for index expressions are compared to ours.
Received 9 July 1998 / Revised 20 April 1999 / Accepted in revised form 28 May 1999 相似文献
138.
Östen Isaksson Theo Lehner 《JOM Journal of the Minerals, Metals and Materials Society》2000,52(8):26-29
In 1998, the Boliden Limited board of directors voted to modernize the Rönnskär copper smelter and refinery to expand production from 130,000 t/y to 230,000 t/y cathodes. Heavy involvement from operations and management was maintained during the modernization project, enabling the realization of project goals while maintaining full production schedules. Early start-up data indicate a smooth transition from the old to the new units. 相似文献
139.
McCulloch I Bailey C Genevicius K Heeney M Shkunov M Sparrowe D Tierney S Zhang W Baldwin R Kreouzis T Andreasen JW Breiby DW Nielsen MM 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2006,364(1847):2779-2787
Organic electronics technology, in which at least the semiconducting component of the integrated circuit is an organic material, offers the potential for fabrication of electronic products by low-cost printing technologies, such as ink jet, gravure offset lithography and flexography. The products will typically be of lower performance than those using the present state of the art single crystal or polysilicon transistors, but comparable to amorphous silicon. A range of prototypes are under development, including rollable electrophoretic displays, active matrix liquid crystal (LC) displays, flexible organic light emitting diode displays, low frequency radio frequency identification tag and other low performance electronics. Organic semiconductors that offer both electrical performance and stability with respect to storage and operation under ambient conditions are required. This work describes the development of reactive mesogen semiconductors, which form large crosslinked LC domains on polymerization within mesophases. These crosslinked domains offer mechanical stability and are inert to solvent exposure in further processing steps. Reactive mesogens containing conjugated aromatic cores, designed to facilitate charge transport and provide good oxidative stability, were prepared and their liquid crystalline properties evaluated. The organization and alignment of the mesogens, both before and after crosslinking, were probed by grazing incidence wide-angle X-ray scattering of thin films. Both time-of-flight and field effect transistor devices were prepared and their electrical characterization reported. 相似文献
140.
Mathieu Noël Theo Guez Dr. Yann Thillier Dr. Jean-Jacques Vasseur Dr. Françoise Debart 《Chembiochem : a European journal of chemical biology》2023,24(22):e202300544
Given the importance of mRNA with 5’-cap, easy access to RNA substrates with different 7mG caps, of high quality and in large quantities is essential to elucidate the roles of RNA and the regulation of underlying processes. In addition to existing synthetic routes to 5’-cap RNA based on enzymatic, chemical or chemo-enzymatic methods, we present here an all-chemical method for synthetic RNA capping. The novelty of this study lies in the fact that the capping reaction is performed on solid-support after automated RNA assembly using commercial 2’-O-propionyloxymethyl ribonucleoside phosphoramidites, which enable final RNA deprotection under mild conditions while preserving both 7mG-cap and RNA integrity. The capping reaction is efficiently carried out between a 5’-phosphoroimidazolide RNA anchored on the support and 7mGDP in DMF in the presence of zinc chloride. Substantial amounts of 7mG-cap RNA (from 1 to 28 nucleotides in length and of any sequence with or without internal methylations) containing various cap structures (7mGpppA, 7mGpppAm, 7mGpppm6A, 7mGpppm6Am, 7mGpppG, 7mGpppGm) were obtained with high purity after IEX-HPLC purification. This capping method using solid-phase chemistry is convenient to perform and provides access to valuable RNA substrates as useful research tools to unravel specific issues regarding cap-related processes. 相似文献