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411.
412.
Steffen Bothe Ali Ayhan Dardagan Marcus Ermler Patrick Fehrmann Christoph Jahn Marshall Nana Vitali Richter Benjamin Vollmer 《Informatik-Spektrum》2011,11(3):501-507
Wie unterstützt man den Schreibprozess einer wissenschaftlichen Arbeit mit modernen Textverarbeitungssystemen? Einige Antworten
auf diese Frage sind im AuthorSupportTool implementiert, das eine Erweiterung für den OpenOffice.org 3 Writer darstellt. Hauptmerkmale
des AuthorSupportTools sind eine Quellen- und Zitatverwaltung, eine Versionsverwaltung zur Unterstützung kooperativer Arbeit
sowie ein grafischer Editor mit Mindmap-Funktion, um Themen, Notizen und Querverbindungen zu verwalten. 相似文献
413.
Ayhan Demirbas Hisham S. Bamufleh Gaber Edris Walid M. Alalayah 《Petroleum Science and Technology》2017,35(9):883-889
The environmental impacts of petroleum are often negative because they are toxic to almost all lifestyles, and there is a possibility of causing climate change. Oil pollution in the air and in the water can be toxic and dangerous to the human body. Preliminary researchers have thoroughly studied and discussed the methods of treatment of oily wastewater. Removing oily wastewater from the oil without damaging the environment is an important problem for the oil industry. The three-phase solid, water, and oil blends can be separated from each other when a continuous oil–water separator system is used. Oil contaminated wastewater is generally treated by gravity sedimentation, coagulation, flotation, coagulation composite flotation, demulsification, membrane separation, flocculation treatment, chemical precipitation, and biological treatment and filtration. 相似文献
414.
Regio‐Selective Chemical‐Enzymatic Synthesis of Pyrimidine Nucleotides Facilitates RNA Structure and Dynamics Studies
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Dr. Luigi J. Alvarado Regan M. LeBlanc Andrew P. Longhini Dr. Sarah C. Keane Dr. Niyati Jain Dr. Zehra F. Yildiz Prof. Blanton S. Tolbert Prof. Victoria M. D'Souza Prof. Michael F. Summers Prof. Christoph Kreutz Prof. T. Kwaku Dayie 《Chembiochem : a European journal of chemical biology》2014,15(11):1573-1577
Isotope labeling has revolutionized NMR studies of small nucleic acids, but to extend this technology to larger RNAs, site‐specific labeling tools to expedite NMR structural and dynamics studies are required. Using enzymes from the pentose phosphate pathway, we coupled chemically synthesized uracil nucleobase with specifically 13C‐labeled ribose to synthesize both UTP and CTP in nearly quantitative yields. This chemoenzymatic method affords a cost‐effective preparation of labels that are unattainable by current methods. The methodology generates versatile 13C and 15N labeling patterns which, when employed with relaxation‐optimized NMR spectroscopy, effectively mitigate problems of rapid relaxation that result in low resolution and sensitivity. The methodology is demonstrated with RNAs of various sizes, complexity, and function: the exon splicing silencer 3 (27 nt), iron responsive element (29 nt), Pro‐tRNA (76 nt), and HIV‐1 core encapsidation signal (155 nt). 相似文献
415.
Ayhan Demirbas 《Fuel》2011,90(6):2273-2279
The purpose of the present paper is to evaluate the potentiality of the wood oil of Oriental spruce (Spruce orientalis) for biodiesel production. Two methods have been applied for obtained wood oil with and without solvent such as separation of crude tall oil from sulfate soaps by Kraft pulping process. Production of biodiesel from wood oil follows two steps, first extraction of oil using a solvent (acetone) and then base catalyzed (KOH) or non-catalytic supercritical methanol transesterification. This paper studied the effect of temperature on transesterification of wood oil to find the optimum temperature of maximum biodiesel yield. Transesterification of the wood oils were performed in a 100-mL cylindrical autoclave using supercritical methanol. In a typical run, the autoclave was charged with a given amount of the wood oil (20-25 g) and alcohol (20-50 g) with changed molar ratios at 500, 525, 550 and 575 K. The yield of the biodiesel produced under optimal condition is 96-98%. 相似文献
416.
Gas chromatography coupled to mass spectrometry using a static head space technique was applied to analyze the volatile aromatic compounds of various melons collected from different locations in Turkey. Some physicochemical and sensory analyses were also made. A total of 33 volatile compounds were identified. Differences in the physicochemical and sensory properties of various Turkish melon samples were observed. The multivariate analyses by the volatile compounds separated the three varieties into groups successfully. The most abundant volatile compounds as mean value in all melon varieties were ethyl acetate (22.10%), acetaldehyde (13.65%), and ethanol (23.25%). The results showed that Cantaloupe melons were more preferred by panelists, which had relatively high levels of esters being responsible for strong fruit flavor, like melon, as well as high total soluble solid content and low titratable acidity compared with Inodorus and Simama. 相似文献
417.
Ayhan Demirbas 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2013,35(16):1509-1518
The goal of this study is to investigate how co-operation between industry and district heating companies can improve profitability of biofueled cogenerative investments in small to medium-sized applications. Currently advanced biomass gasification and gas turbine combined cycle has been found to be a promising cogenerative conversion technology for the recovery of heat present in biomass fuel. Increased biofuel based cogenerative power production in the future is clearly dependent on the improvement of both performance and investment costs of new high performance technology, and on the nature of policy instruments designed to promote the technology. The use of biofuels for cogeneration on a large scale is focused mainly on forest industry sites, where considerable quantities of biomass are available. While cogeneration provides several environmental benefits by making use of waste heat and waste products, air pollution is a concern any time fossil fuels or biomass are burned. 相似文献
418.
Conventional expandable polystyrene (EPS) was modified by the preparation of copolymers containing 0.10%, 0.25%, and 0.50% silicone acrylate. Copolymeric expandable polystyrene (CEPS) samples were characterized with various techniques. 1H‐NMR spectroscopy was used for the determination of composition, and gel permeation chromatography was used for the determination of molecular weight and molecular weight distribution. Differential scanning calorimetry showed that the glass‐transition temperatures of the CEPS samples increased with an increasing silicone acrylate content. The surface properties of the copolymers were investigated by contact angle measurement and SEM imaging. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 128–132, 2006 相似文献
419.
Ayhan Ozguler Scott A. Morris William D. O'brien 《Polymer Engineering and Science》2001,41(5):830-839
Ultrasonic Backscattered Amplitude Integral (BAI) values are used to detect critical and major defects such as nonbonding, wrinkles and bubbles distributed within the seal area of flexible food packages. The BAI‐mode imaging by itself is not capable of detecting such nonbonding, wrinkles and bubbles distributed within the seal area. For this study, model delects in the seal region of all‐plastic and foil‐containing films were created by varying the sealing‐bar temperature. Seal regions were scanned by a 17.3‐MHz ultrasonic transducer, and the waveform for each scan point was processed by the BAI‐mode method. The mean and the coefficient of variation of the BAI values (BAICV) were calculated. It is shown that a combination of mean BAI vaiae and BAICV value can detect defects distributed in seals in flexible food packages. This technique has the potential of providing a real‐time, on‐line control by sensing whether a proper seal has been achieved. 相似文献
420.
Ayhan Demirbas 《Biomass & bioenergy》2009,33(1):113-118
Methyl and ethyl esters as biodiesel fuels were prepared from linseed oil with transesterification reaction in non-catalytic supercritical fluids conditions. Biodiesel fuel is a renewable substitute fuel for petroleum diesel fuel made from vegetable or animal fats. Biodiesel fuel has better properties than that of petroleum diesel fuel such as renewable, biodegradable, non-toxic, and essentially free of sulfur and aromatics. The purpose of the transesterification process is to lower the viscosity of the oil. The viscosity values of linseed oil methyl and ethyl esters highly decreases after transesterification process. The viscosity values of vegetable oils vary between 27.2 and 53.6 mm2 s?1, whereas those of vegetable oil methyl esters between 3.59 and 4.63 mm2 s?1. Compared with no. 2 diesel fuel, all of the vegetable oil methyl esters were slightly viscous. The flash point values of vegetable oil methyl esters are highly lower than those of vegetable oils. The transesterification of linseed oil in supercritical fluids such as methanol and ethanol has proved to be the most promising process. Methanol is the commonly used alcohol in this process, due in part to its low cost. Methyl esters of vegetable oils have several outstanding advantages among other new-renewable and clean engine fuel alternatives. The most important variables affecting the methyl ester yield during the transesterification reaction are molar ratio of alcohol to vegetable oil and reaction temperature. Biodiesel has become more attractive recently because of its environmental benefits. Biodiesel is an environmentally friendly fuel that can be used in any diesel engine without modification. 相似文献