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91.
Brett M. Davis Senti T. Senthilmohan Murray J. McEwan 《Journal of the American Oil Chemists' Society》2011,88(6):785-792
A modified Selected Ion Flow Tube Mass Spectrometry Total Oxyradical Scavenging (SIFT-MS-TOSC) assay has been used to assess the antioxidants present in olive oil samples. The assay compares antioxidants in emulsified olive oil competing with added 2-keto-4-methylthiobutanoic acid (KMBA) for peroxyl radicals formed from thermal decomposition of 2,2′-azobis (2-amidinopropane) hydrochloride. No solvent extraction from the oil is required. The assay reaction is monitored by analysis of ethene, a break down product of KMBA, from attack by peroxyl radicals. A new simpler modification to the TOSC assay was found to produce reliable results requiring measurements of just a single concentration of emulsion. The results of the SIFT-MS-TOSC assay show correlation with results from the Folin Ciocalteu assay of total phenol content and HPLC analysis of several standard antioxidants. The use of hydroxyl radicals generated by the Fenton reaction of Fe3+ with ascorbic acid was also investigated, but with less repeatable results. A wide range of antioxidant levels differing by more than a factor of 10 were found in 20 different olive oils examined. 相似文献
92.
Murray R. Gray 《加拿大化工杂志》2002,80(3):393-401
A number of coking processes use hot particles to heat liquid bitumen or petroleum residue to cause cracking reactions. These particles may be mineral or coke solids. Interactions of these particles, in fluid beds, moving beds and other types of contactors, are governed by the liquid films on the particle surfaces. This paper explores the analogy between granulation and coking, and suggests that the key relationships that will govern the behavior of wet particles in coking processes are the Stokes number of the particles, the thickness or the liquid films, and the diameter and surface roughness of the particles. The implications for distribution of liquid feed in the reactor, fouling, and defluidization or bogging are discussed. This analysis suggests experiments that can be performed under non‐reactive conditions with scaled variables in order to study phenomena that cannot be observed in situ in high‐temperature cracking processes. 相似文献
93.
Pevindu Abeysinghe Natalie Turner Isabella Morean Garcia Eman Mosaad Hassendrini N. Peiris Murray D. Mitchell 《International journal of molecular sciences》2020,21(23)
Abnormal uterine function affects conception rate and embryo development, thereby leading to poor fertility and reproduction failure. Exosomes are a nanosized subclass of extracellular vesicles (EV) that have important functions as intercellular communicators. They contain and carry transferable bioactive substances including micro RNA (miRNA) for target cells. Elements of the cargo can provide epigenetic modifications of the recipient cells and may have crucial roles in mechanisms of reproduction. The dairy industry accounts for a substantial portion of the economy of many agricultural countries. Exosomes can enhance the expression of inflammatory mediators in the endometrium, which contribute to various inflammatory diseases in transition dairy cows. This results in reduced fertility which leads to reduced milk production and increased cow maintenance costs. Thus, gaining a clear knowledge of exosomal epigenetic modifiers is critical to improving the breeding success and profitability of dairy farms. This review provides a brief overview of how exosomal miRNA contributes to inflammatory diseases and hence to poor fertility, particularly in dairy cows. 相似文献
94.
Prof. Michael Murray Dr. Ariane Roseblade Dr. Yongjuan Chen Kirsi Bourget Dr. Tristan Rawling 《ChemMedChem》2020,15(2):247-255
Targeting the tumor cell mitochondrion could produce novel anticancer agents. We designed an aryl−urea fatty acid ( 1 g ; 16({[4-chloro-3-(trifluoromethyl)phenyl]carbamoyl}amino)hexadecanoic acid) that disrupted the mitochondrion and decreased MDA-MB-231 breast cancer cell viability. To optimize the aryl−ureas the present study evaluated mitochondrial targeting by 1 g analogues containing alkyl chains between 10–17 carbons. Using the dye JC-1, the C12−C17 analogues efficiently disrupted the mitochondrial membrane potential (IC50s 3.5±1.2 to 7.6±1.1 μM) and impaired ATP production; shorter analogues were less active. 7-Aminoactinomycin D/annexin V staining and flow cytometry showed that these agents activated the killing mechanisms of necrosis and apoptosis to varying extents (7-aminoactinomycin D/annexin V staining ratios 4.3–6.0). Indeed, 1 g and its C17 analogue preferentially activated necrosis and apoptosis, respectively (ratios 2.1 and 16). Taken together, alkyl chain length is a determinant of mitochondrial targeting by aryl−ureas and can be varied to develop analogues that activate apoptosis or necrosis in a regulated fashion. 相似文献
95.
Analysis of the Insect OS-D-Like Gene Family 总被引:9,自引:0,他引:9
Wanner KW Willis LG Theilmann DA Isman MB Feng Q Plettner E 《Journal of chemical ecology》2004,30(5):889-911
Insect OS-D-like proteins, also known as chemosensory (CSP) or sensory appendage proteins (SAP), are broadly expressed in various insect tissues, where they are thought to bind short to medium chain length fatty acids and their derivatives. Although their specific function remains uncertain, OS-D-like members have been isolated from sensory organs (including the sensillum lymph in some cases), and a role in olfaction similar to that of the insect odorant binding proteins (OBP) has been suggested for some. We have identified 15 new OS-D-like sequences: four from cDNA clones described herein and 11 from sequence databases. The os-d-like genes from the Anopheles gambiae, Apis mellifera, Drosophila melanogaster, and Drosophila pseudoobscura genomes typically have single, small introns with a conserved splice site. Together with all family members entered on GenBank, a total of 70 OS-D-like proteins, representing the insect orders Diptera, Dictyoptera, Hymenoptera, Lepidoptera, Orthoptera, and Phasmatodea, were analyzed. A neighbor joining distance phenogram identified several protein similarity classes that were characterized by highly conserved sequence motifs, including (A) N-terminal YTTKYDN(V/I)(N/D)(L/V)DEIL, (B) central DGKELKXX(I/L)PDAL, and (C) C-terminal KYDP. In contrast, three similarity classes were characterized by their diversion from these conserved motifs. The functional importance of conserved amino acid residues is discussed in relation to the crystal and NMR structures of MbraCSPA6. 相似文献
96.
Thioether‐Functionalized Corn Oil Biosorbents for the Removal of Mercury and Silver Ions from Aqueous Solutions 下载免费PDF全文
Robert O. Dunn Grigor B. Bantchev Kenneth M. Doll Kim L. Ascherl James C. Lansing Rex E. Murray 《Journal of the American Oil Chemists' Society》2018,95(9):1189-1200
Heavy‐metal contamination is one of the most important environmental problems faced in the world, particularly in developing countries. Metals such as silver and mercury from drinking water, food, and air sources can accumulate in living organisms and present significant health concerns. Meanwhile, the demand for these metals in many industries continues to increase. In the present study, thioether‐functionalized corn oil (TFCO) from a photoinitiated thiol‐ene synthesis was utilized to remove Ag+ and Hg2+ ions from an aqueous solution. An aqueous solution containing AgNO3 and Hg[NO3]2 was prepared and contacted directly with TFCO. After vortex mixing for 60 s, the experiment ran for 351 min with the aqueous phase being periodically sampled for the analysis of metal ions (M n+). Results showed that 88.9% of Ag+ and 99.6% of Hg2+ ions were removed from the aqueous phase by the TFCO. Mass balances indicated that the total M n+ concentration in the oil phase was 13.890 g kg?1 under the conditions studied. TFCO exhibited higher selectivity for removing Hg2+ than for Ag+ ions. Analysis of the adsorption kinetics showed that a pseudosecond‐order model may be used to determine the rate of Ag+ ion sorption by the oil phase. The presence of the Hg2+ ions interfered with the adsorption of Ag+ ions from the aqueous solution. 相似文献
97.
During electrical discharge machining (EDM), ablated workpiece material is rapidly solidified upon ejection into the dielectric and thought not to become reattached to the electrode surfaces. This work furthers the understanding of the little understood discharge gap phenomena by investigating the attachment of machined material back onto the tool electrode surface and explains the mechanism of this attachment. After the machining of high-aspect ratio slots, SEM and EDS techniques along with single discharge and cross-sectional analysis were used to explain that debris reattachment onto the tool electrode does not occur randomly but is dependent on its remelting in the dielectric by the secondary discharge process. The subsequently bonded material is present mainly in the centre of the discharge crater, with no attachment occurring outside of discharge affected regions. The surfaces of electrodes subject to intense secondary sparking are therefore liable to transient surface properties dependent on the composition of the deposited material. It is also observed that the deposited material on the tool electrode can offer a protective effect against wear from further secondary discharges and so potentially enhancing tool life. 相似文献
98.
P. J. R. Smith M. P. Taylor H. E. Evans N. E. Murray C. McMillan J. Cherrington 《Oxidation of Metals》2014,81(1-2):47-55
Current thermal barrier coating systems (TBCs) rely on an alumina-forming bond coat to provide protection against oxidation. At bond coat temperatures below 900 °C, however, optimum protection against oxidation and hot corrosion is best achieved by a chromia layer. TBC systems using this approach are currently being developed and an example is examined in this paper. The multilayered bond coat in the present TBC system consisted of: a NiCrAlY layer aluminised at its surface; a 50:50 NiCr layer (containing 1.8 wt% Si); an air plasma sprayed yttria stabilised zirconia top coat. These samples were oxidised in laboratory air at 750, 800 and 850 °C for durations up to 1,000 h. Post-test characterisation was undertaken using SEMs and energy dispersive X-ray spectroscopy to determine the growth rate of the TGO and to investigate interdiffusion within the layered coating structure. The interdiffusion process was also modelled using the ODIN finite difference code. 相似文献
99.
Adam Clare Alex Gullane Christopher Hyde James W. Murray Simon Sankare Wessel W. Wits 《CIRP Annals》2021,70(1):203-206
The geometrical design freedoms associated with additive manufacturing techniques are currently well exploited and finding commercial application. The capability of layer-based processes to allow modification of composition and microstructure in process to achieve functional grading is currently a growing topic. In this work, a method is demonstrated for varying layer thickness within single components that allows part sections to be interlaced for the purpose of locally manipulating material and structural properties. Demonstrator geometries are explored here which exhibit the interfaces within specimens constituted of both 30 µm and 150 µm. Accordingly, a new design freedom for laser powder bed fusion is created. 相似文献
100.
Wanwisa Skolpap Somboon Nuchprayoon Jeno M. Scharer Nurak Grisdanurak Peter L. Douglas Murray Moo-Young 《Korean Journal of Chemical Engineering》2008,25(4):646-655
A modified Markov Chain Monte Carlo (MCMC) searching procedure was developed to search for an optimal set of decision variables
and optimal feed rate trajectories for recombinant α-amylase expression by Bacillus subtilis ATCC 6051a. The bacterium also synthesizes proteases as undesirable products in fed-batch culture that need to be minimized.
To maximize α-amylase productivity, a 14th-order fed-batch model was optimized by integrating Pontryagin’s maximum principle with the Luedeking-Piret equation. The number of iterations and simulations of the proposed searching procedure were statistically examined for accuracy
and acceptability of the results. It can be concluded that the proposed searching procedure increased the parameter selection
opportunity near the tail ends of redefined triangular distribution. By applying a modified MCMC searching procedure with
1,500 iterations, the predicted α-amylase productivity was improved by 18% in comparison with near-optimum experimental results. This productivity was 3.5%
higher than predicted by conventional MCMC optimization. 相似文献