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91.
Mellisho CD González-Barrio R Ferreres F Ortuño MF Conejero W Torrecillas A García-Mina JM Medina S Gil-Izquierdo A 《Journal of the science of food and agriculture》2011,91(12):2132-2139
BACKGROUND This study was designed to describe the phenolic status of lemon juice obtained from fruits of lemon trees differing in iron (Fe) nutritional status. Three types of Fe(III) compound were used in the experiment, namely a synthetic chelate and two complexes derived from natural polymers of humic and lignine nature. RESULTS All three Fe(III) compounds were able to improve the Fe nutritional status of lemon trees, though to different degrees. This Fe(III) compound effect led to changes in the polyphenol content of lemon juice. Total phenolics were decreased (~33% average decrease) and, in particular, flavanones, flavones and flavonols were affected similarly. CONCLUSION Iron‐deficient trees showed higher phenolic contents than Fe(III) compound‐treated trees, though Fe deficiency had negative effects on the yield and visual quality of fruits. However, from a human nutritional point of view and owing to the health‐beneficial properties of their bioavailable phenolic compounds, the nutritional quality of fruits of Fe‐deficient lemon trees in terms of phenolics was higher than that of fruits of Fe(III) compound‐treated lemon trees. Moreover, diosmetin‐6,8‐di‐C‐glucoside in lemon juice can be used as a marker for correction of Fe deficiency in lemon trees. Copyright © 2011 Society of Chemical Industry 相似文献
92.
Amotchkina TV Trubetskov MK Tikhonravov AV Janicki V Sancho-Parramon J Zorc H 《Applied optics》2011,50(33):6189-6197
In the present study we determine the optical parameters of thin metal-dielectric films using two different characterization techniques based on nonparametric and multiple oscillator models. We consider four series of thin metal-dielectric films produced under various deposition conditions with different optical properties. We compare characterization results obtained by nonparametric and multiple oscillator techniques and demonstrate that the results are consistent. The consistency of the results proves their reliability. 相似文献
93.
Vesna Janicki Jordi Sancho-ParramonHrvoje Zorc Krešimir SalamonMaja Buljan Nikola Radi?Uroš Desnica 《Thin solid films》2011,519(16):5419-5423
Mixture layers of Ge:SiO2 of 40:60 mol% respectively, have been prepared by co-sputtering. The thermally induced change of optical properties of the layers was studied by variable angle spectroscopic ellipsometry. The mixture was modelled as an unknown material with optical constants described by multiple oscillators. The optical parameters determined from ellipsometric measurements can be well correlated with structural changes in the mixture. The results indicate that Ge in the mixture deposited or annealed up to 600 °C is in an amorphous state and it redistributes with increase of temperature, changing refractive index through the layer. The crystallization starts between 600 and 650 °C, at first next to the substrate. Crystallites size grows with temperature. Results were compared with findings of grazing incidence wide angle X-ray scattering measurements and a good agreement was found. Ellipsometry has been shown to be an appropriate non-invasive technique for characterization of this kind of layers. 相似文献
94.
The systematized study of urban morphology has led to the development of integrated tools based on the knowledge of the relation between physical density and urban form. These tools do help planners and decision makers; however, environmental data is rarely included in them.This paper presents the GWP-Chart, a method that combines urban planning tools with environmental data, obtained through the use of the life cycle assessment (LCA) results. In order to explain its use, three urban fabrics have been selected. According to their morphology and their ground space index (GSI) and public space ratio (PSR) values, the contribution of the sidewalk subsystem to the global impact per square meter of urban development can be quantified and communicated.The GWP-Chart is applicable to all types of urban fabrics and scales (street or square, island, fabric or district), as well as adaptable to any urban infrastructure or subsystem and can be extended to other environmental impacts. Its advantages lie in its accurateness, adaptability and ease of interpretation. 相似文献
95.
Jordi Perelló Annalisa Morea Salvatore Spadaro Albert Pagès Sergio Ricciardi Matthias Gunkel Gabriel Junyent 《Photonic Network Communications》2014,28(3):276-286
Network survivability requires the provisioning of backup resources in order to protect active traffic against any failure scenario. Backup resources, however, can remain unused most of the time while the network is not in failure condition, inducing high power consumption wastage, if fully powered on. In this paper, we highlight the power consumption wastage of the additional resources for survivability in IP/multi-protocol label switching (MPLS) over dense wavelength division multiplexing multi-layer optical networks. We assume MPLS protection switching as the failure recovery mechanism in the network, a solution interesting for current network operators to ensure fast recovery as well as fine-grained recovery treatment per label switched path. Next, we quantitatively show how elastic optical technologies can effectively reduce such a power consumption by dynamically adjusting the data rate of the transponders to the carried amount of traffic. 相似文献
96.
Purification and characterization of X-prolyl-dipeptidyl-aminopeptidase from Lactobacillus lactis and from Streptococcus thermophilus 总被引:3,自引:0,他引:3
X-Prolyl-dipeptidyl-aminopeptidase recently was found in several lactic acid bacteria. This article describes the purification of the enzymes from Lactobacillus lactis and Streptococcus thermophilus and compares their characteristics. Enzymes from both strains are serine-peptidases. They both have a molecular weight of about 165,000 daltons, an isoelectric point near 4.5, and are constituted of two subunits. The pH optimum of the enzyme isolated from L. lactis is 7.0, whereas the enzyme from S. thermophilus possesses a broad pH optimum between 6.5 and 8.2 with glycyl-L-prolyl-aminomethylcoumarin as substrate. Below pH 5, both enzymes are unstable; however, that from S. thermophilus is more rapidly denatured. The enzyme from S. thermophilus is more sensitive to heat than the corresponding enzyme from L. lactis. Enzymes from the both strains have different specificities towards various substrates and are differently effected by metals, chelators, and other inhibitors. The importance of this enzyme for the metabolism of lactic acid bacteria is discussed. 相似文献
97.
Djamel Mostefa Nicolas Moreau Khalid Choukri Gerasimos Potamianos Stephen M. Chu Ambrish Tyagi Josep R. Casas Jordi Turmo Luca Cristoforetti Francesco Tobia Aristodemos Pnevmatikakis Vassilis Mylonakis Fotios Talantzis Susanne Burger Rainer Stiefelhagen Keni Bernardin Cedrick Rochet 《Language Resources and Evaluation》2007,41(3-4):389-407
98.
C Rumi S Rutella L Teofili B Etuk E Ortu La Barbera G Micciulli MT Voso G Leone 《Canadian Metallurgical Quarterly》1997,25(3):246-251
OBJECTIVE: The purpose of this study was to differentiate between the catabolic effects of interleukin-1 (IL-1) when infused into the central nervous system or into the periphery. SUMMARY BACKGROUND DATA: After injury and infection, IL-1 has been found in the central nervous system. Chronic intracerebrovascular infusion of IL-1 produces protein catabolism, anorexia, and fever. However, IL-1 may act directly on liver and bone marrow to elicit metabolic responses. Although IL-1 is thought to be involved in a number of metabolic responses associated with injury-inflammation, the sites of action are unclear. METHODS: Rats were implanted with chronic infusion pumps and received diluent or three doses of IL-1 infused subcutaneously for 6 days, and a variety of response variables were measured. In a second study, doses were adjusted so that similar systemic catabolic responses were obtained from peripheral and intracerebroventricular infusion of IL-1. The acute-phase responses then were compared in the two groups of animals receiving IL-1 by different routes. RESULT: Subcutaneously infused IL-1 elicited catabolic responses in a dose-response manner. Similar catabolic responses were achieved by infusing one tenth of the dose of IL-1 given subcutaneously into the central nervous system. Although similar systemic responses (protein catabolism, anorexia, fever, and weight loss) were observed with both routes of infusion, the subcutaneous infusion produced a much greater lymphocytosis, elevation in acute-phase reactants, and fall in serum iron and albumin. CONCLUSIONS: The IL-1 appears to have different effects depending on the site of production and site of action. Regionalization of signal proteins such as IL-1 should be taken into consideration when devising specific anticytokine treatment strategies. 相似文献
99.
100.
M Fernández Lucas R Marcén J Villafruela JL Teruel A Tato M Rivera J Ortu?o 《Canadian Metallurgical Quarterly》1996,73(1):54-57
BACKGROUND: Pertussis is a highly contagious respiratory disease and the most serious effects occur in young infants. Recently it has been shown that rapid and highly specific PCR can be a useful diagnostic tool for detection of pertussis infection. To our knowledge there are no previous studies concerning the disappearance of Bordetella pertussis DNA from the nasopharynx during antimicrobial treatment. METHODS: We studied prospectively how rapidly live B. pertussis organisms and DNA of these bacteria disappear from the nasopharynx during erythromycin therapy in unvaccinated infants. Eighty-five nasopharyngeal swabs obtained from nine erythromycin-treated infants with pertussis on consecutive days during hospitalization were tested by PCR and culture. The PCR products were further analyzed by Southern hybridization. RESULTS: On the fourth day of treatment 56% of the samples were positive by culture and 89% by PCR, whereas after 7 days the rates were 0 and 56%, respectively. In seven of nine patients PCR remained positive for 1 to 7 days longer than culture. The follow-up study also showed the semiquantitative nature of the PCR assay. The intensity of the PCR products in agarose gel usually weakened with time during erythromycin therapy. CONCLUSIONS: The results of this study show that PCR assay can achieve the specific diagnosis of pertussis infection in a large proportion of infants even when antimicrobial treatment has killed the organisms and culture is no longer positive. 相似文献