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81.
Recommended drying treatments may not enhance destruction of pathogens that could be present on home-dried foods. In this study, the effects of traditional and modified treatments on Salmonella were evaluated during preparation, home-type dehydration (60 degrees C for 6 h), and storage of potato slices. Potato slices inoculated with five strains of Salmonella (8.4 log CFU/ g) were left untreated or were treated by steam blanching (88 degrees C for 10 min), water blanching (88 degrees C for 4 min), 0.105% citric acid blanching (88 degrees C for 4 min), or 0.210% citric acid blanching (88 degrees C for 4 min). Slices were then dried (6 h for 60 degrees C) and aerobically stored for up to 30 days at 25 +/- 3 degrees C. Cells were enumerated on tryptic soy agar with 0.1% pyruvate (TSAP) and on xylose lysine deoxycholate agar. Salmonella populations were reduced by 4.5 to 4.8 CFU/g and by >5.4 log CFU/g immediately following steam and water blanching, respectively. Populations were below the detection limit (0.80 log CFU/g) immediately following acid blanching, except for samples blanched in 0.105% citric acid and recovered on TSAP. After dehydration (6 h for 60 degrees C), Salmonella reductions on blanched potato slices (5.3 to 5.6 log CFU/g) were significantly greater (P < 0.05) than those on untreated samples (1.9 to 2.7 log CFU/g). Populations on all samples continued to decrease throughout 30 days of storage but still were 3.1 to 3.9 log CFU/g on untreated samples. In comparison, bacterial populations on blanched samples were undetectable by direct plating following 30 days of storage (regardless of blanching method). Blanching treatments used in this study improved the effectiveness of drying for inactivating Salmonella inoculated onto potato slices and, therefore, may enhance the safety of the product. 相似文献
82.
Mehmet Erdi Korkmaz Patricia Verleysen Mustafa Günay 《Transactions of the Indian Institute of Metals》2018,71(12):2945-2952
Nimonic 80A is a nickel-chrome superalloy, commonly used due to its high resistance against creep, oxidation, and temperature corrosion. This paper presents the material constitutive models of Nimonic 80A superalloy. Johnson–Cook (JC) and modified JC model is preferred among the different material constitutive equations (Zerill Armstrong, Bodner Partom, Arrhenius type) due to its accuracy in the literature. Three different types of compression tests were applied to determine the equation parameters. Firstly, quasi-static tests were performed at room temperature. These tests were conducted at 10?3, 10?2, and 10?1 s?1 strain rates. Secondly, compression tests were performed at room temperature at high strain rates (370–954 s?1) using the Split-Hopkinson pressure bar. Finally, compression tests were performed at a temperature level from 24 to 200 °C at the reference strain rate (10?3 s?1). Johnson–Cook and modified JC model parameters of Nimonic 80A were determined with the data obtained from these tests, and they were finally verified statistically. 相似文献
83.
Coffey Patricia; Leitenberg Harold; Henning Kris; Turner Tonia; Bennett Robert T. 《Canadian Metallurgical Quarterly》1996,64(5):1090
With a community sample of 192 women who had been sexually abused during childhood, the investigators determined if methods of coping in adulthood with the aftermath of child sexual abuse were associated with current symptoms of psychological distress. Multiple regression analyses indicated that disengagement methods of coping with the sexual abuse accounted for unique variance in general psychological distress even after controlling for characteristics of the abuse and methods of coping with other stressors. Disengagement methods of coping were also used more often to deal with the stressful aspects of having been sexually abused than to deal with other stressful events. In contrast, engagement methods of coping were used more often to deal with the other stressors than with sexual abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Kalyani?Dias Deland?J.?MyersEmail author Yilin?Bian Makuba?A.?Lihono Shaowen?Wu Patricia?A.?Murphy 《Journal of the American Oil Chemists' Society》2003,80(6):551-555
The functional properties of low- and high-M.W. (LMW and HMW, respectively) acidic subunits and the basic subunit separated
from the 11S soy protein fraction were studied and compared with the functional properties of the 11S fraction. Among the
functional properties investigated were solubility, emulsification, and viscosity. The results showed that the LMW acidic
subunit had higher solubility than the HMW acidic subunit. Among all the samples, the LMW subunit separated by using β-mercaptoethanol
(ME) was the most soluble, with a solubility of 98–100% at a pH of 6–12. The solubility profile of the HMW subunit followed
a pattern similar to the solubility of 11S. The lowest solubility was observed around pH values in the range close to the
isoelectric point for both the LMW and HMW subunit. The basic subunit was not soluble in the pH range 3–10; however, the solubility
increased more than 50% at pH 13 compared to the solubility at pH 10. The emulsification capacity of all subunits was higher
than 11S in the following descending order: LMW, basic, HMW, 11S. Emulsification activity and stability of the subunits were
greater than those of the 11S samples at room temperature and 95°C. With the exception of the LMW subunit separated with ME,
the subunits had a higher viscosity than 11S. The basic subunit separated with sodium bisulfite had the highest viscosity
of all the samples tested. 相似文献
85.
Shelley Waters Silvia Lee Ibnu Ariyanto Shay Leary Kylie Munyard Silvana Gaudieri Ashley Irish Richard J. N. Allcock Patricia Price 《International journal of molecular sciences》2022,23(21)
Around 80% of adults worldwide carry human cytomegaloviris (HCMV). The HCMV gene UL18 is a homolog of HLA class I genes and encodes a protein with high affinity for the NK and T-cell cytotoxicity inhibitor LIR-1. UL18 was deep sequenced from blood, saliva or urine from Indonesian people with HIV (PWH) (n = 28), Australian renal transplant recipients (RTR) (n = 21), healthy adults (n = 7) and neonates (n = 4). 95% of samples contained more than one variant of HCMV UL18, as defined by carriage of nonsynonymous variations. When aligned with immunological markers of the host’s burden of HCMV, the S318N variation associated with high levels of antibody reactive with HCMV lysate in PWH over 12 months on antiretroviral therapy. The A107T variation associated with HCMV antibody levels and inflammatory biomarkers in PWH at early timepoints. Variants D32G, D248N, V250A and E252D aligned with elevated HCMV antibody levels in RTR, while M191K, E196Q and F165L were associated with HCMV-reactive T-cells and proportions of Vδ2− γδ T-cells—populations linked with high burdens of HCMV. We conclude that UL18 is a highly variable gene, where variation may alter the persistent burden of HCMV and/or the host response to that burden. 相似文献
86.
Factors Influencing the Adhesion of Microorganisms to Surfaces 总被引:4,自引:0,他引:4
Brenda J. Little Patricia Wagner James S. Maki Marianne Walch Ralph Mitchell 《The Journal of Adhesion》1986,20(3):187-210
Starvation, growth phase, and carbon source influenced bacterial cell surface hydrophobicity. Both the number and kind of microorganisms that colonized metal surfaces depended on the type of metal and the presence of an imposed electrical potential. No significant differences in attachment and growth of a pure culture were observed when metal surfaces were dipped in an exogenous energy source. The chemical composition of naturally occurring adsorbed organic films on metal surfaces was shown to be independent of surface composition and polarization. 相似文献
87.
Patricia Concepción José M. López Nieto Joaquín Pérez-Pariente 《Catalysis Letters》1993,19(4):333-337
VAPO-5 and V/ ALPO-5 catalysts have been tested for the oxidative dehydrogenation of propane. Depending on the vanadium contents and the preparation procedure, different vanadium species and different catalytic behavior are observed. The catalyst containing V5+ species with a tetrahedral coordination presents the higher yield of propene in the oxidative dehydrogenation of propane. The same yields of CO2 are observed on all vanadium aluminophosphate catalysts, while the higher the yield of propene the lower the yield of CO is. 相似文献
88.
Venkatesh Balan Chad A. Rogers Shishir P. S. Chundawat Leonardo da Costa Sousa Patricia J. Slininger Rajesh Gupta Bruce E. Dale 《Journal of the American Oil Chemists' Society》2009,86(2):157-165
We have come up with a novel, integrated approach for making biodiesel by in-house producion of ethanol after fermentation
of hexane extracted edible oil cake fiber. In addition, we have demonstrated how ethanol could be manufactured from commonly
available oil cakes (such as canola, sunflower, sesame, soy, peanut) and dried distiller’s grains with solubles (DDGS). The
edible oil cakes and DDGS were hexane extracted, ammonia fiber expansion pretreated, enzymatically hydrolysed and fermented
to produce ethanol. From all the oil cakes tested in this work, DDGS and peanut oil cake showed the most promising results
giving more than 180 g of glucose/kg of oil cake. These two feedstock’s were hydrolyzed at 15% solids loading and fermented
by a native strain of Pichia stipitis. Most sugars were consumed during the first 24 h, with no pronounced inhibition of P. stipitis by the degradation products in the hydrolysate. Xylose consumption was more effective for peanut cake hydrolyzate compared
to DDGS. 相似文献
89.
Gimerson Weigert Subtil Jean César Marinozi Vicentini Daiane Marques de Oliveira Lidiane Vizioli de Castro-Hoshino Patricia Hissae Yassue-Cordeiro Renata Corrêa Vicentino Mara Heloisa Neves Olsen Scaliante 《加拿大化工杂志》2023,101(3):1345-1357
The photocatalyst composition affects the chemical–physical properties and directly impacts photocatalytic activity, both in the hydrogen production and degradation of organic contaminants. In this work, the influence of zeolitic structures NaA, NaY, and ZSM-5 combined with a 10% active phase, TiO2 catalyst doped with 1% copper, and cobalt cocatalysts was tested to mineralize the reactive blue dye (CI250) and to produce hydrogen by photocatalysis under ultraviolet radiation. The band gap energy was affected mainly by the cocatalyst, while the Brunauer-Emmett-Teller method (BET) area was affected by the zeolite structure as well as the X-ray diffraction (XRD). The most active catalyst was the Cu@TiO2/NaY, which promoted a hydrogen production rate of 240 μmolH2gcat−1 using 10% ethanol (v/v) aqueous solution as a sacrificial agent and mineralization of 53% of the organic dye, followed by the catalysts impregnated on ZSM-5 zeolites, which had discolouration up to 50% and hydrogen evolution of 92.6 and 109.7 μmolH2gcat−1 for the catalyst doped with Cu and Co, respectively. 相似文献
90.
Antonela B. Orofino Gustavo Arenas Ileana Zucchi María J. Galante Patricia A. Oyanguren 《Polymer》2013
Azobenzene containing epoxy networks are a class of photosensitive materials characterized by high thermal, optical and mechanical stability, promising for reversible optical storage applications. Here, we propose an encouraging two-step method to fabricate crosslinked coatings by simply reacting an amine-functionalized azobenzene and an epoxy resin in bulk for specified times to get soluble products (network precursors). Thin films based on these precursors were prepared, and thermally crosslinked in order to obtain high-Tg materials. The optical response of the materials was determined, both before and after crosslinking. In the case of the samples as prepared, the dynamic time response of the system is fast, as well as the relaxation of the photoinduced birefringence, as expected due to the high mobility of the chromophore. On the other hand, crosslinked systems have a slightly slower response, but higher values of remnant birefringence, providing stability of the photoinduced orientation, what makes them promising materials to use in optical storage applications. Besides, further analysis on the effect of temperature on the induced birefringence of the polymeric networks was also conducted to help optimization of material design. Finally, we had presented some preliminary investigations of surface relief grating recording in the obtained new materials. 相似文献