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81.
This paper describes the work of the International Boundary and Water Commission, United States and Mexico (IBWC), to find cooperative solutions to issues pertaining to the Colorado River along the US-Mexico border. Since 1944, the IBWC has worked to resolve issues related to the distribution of the waters of the Colorado River between the United States and Mexico; salinity of waters delivered to Mexico; conveyance capacity of the Colorado River; and the conditions of the Colorado River Delta. The IBWC has emphasized binational cooperation to explore both short-term and long-term solutions to these issues. 相似文献
82.
Dr. Yun Wang Dr. Shougang Hu Abdul M. Gabisi Jr. Joyce A. V. Er Arthur Pope Gayle Burstein Christopher L. Schardon Dr. Arturo J. Cardounel Dr. Suhendan Ekmekcioglu Dr. Walter Fast 《ChemMedChem》2014,9(4):792-797
Inhibitors of the human enzyme dimethylarginine dimethylaminohydrolase‐1 (DDAH‐1) can raise endogenous levels of asymmetric dimethylarginine (ADMA) and lead to a subsequent inhibition of nitric oxide synthesis. In this study, N5‐(1‐imino‐2‐chloroethyl)‐L ‐ornithine (Cl‐NIO) is shown to be a potent time‐ and concentration‐dependent inhibitor of purified human DDAH‐1 (KI=1.3±0.6 μM ; kinact=0.34±0.07 min?1), with >500‐fold selectivity against two arginine‐handling enzymes in the same pathway. An activity probe is used to measure the “in cell” IC50 value (6.6±0.2 μM ) for Cl‐NIO inhibition of DDAH‐1 artificially expressed within cultured HEK293T cells. A screen of diverse melanoma cell lines reveals that a striking 50/64 (78 %) of melanoma lines tested showed increased levels of DDAH‐1 relative to normal melanocyte control lines. Treatment of the melanoma A375 cell line with Cl‐NIO shows a subsequent decrease in cellular nitric oxide production. Cl‐NIO is a promising tool for the study of methylarginine‐mediated nitric oxide control and a potential therapeutic lead compound for other indications with elevated nitric oxide production, such as septic shock and idiopathic pulmonary fibrosis. 相似文献
83.
Solar cells based on polycrystalline semiconductor thin films have great potential for decreasing the cost of photovoltaic energy. However, this kind of solar cells has characteristics very different from those fabricated on crystalline silicon for which the carrier-transport and behavior is clearly known. Instead, for hetero-junction solar cells made on less known polycrystalline materials the design is almost empirical. In this work, several physical aspects related to the behavior of polycrystalline thin film solar cells will be discussed, and some considerations for an adequate design of this kind of solar cells will be made. For example, the recombination at the grain boundaries and its influence on the short circuit current as a function of the crystallite sizes on the active material is considered. Based on this, the appropriate thickness of each layer and their resistivity will be discussed. As an example, these considerations will be applied to CdS/CdTe heterojunction solar cells, taking into account typical properties of CdTe thin films used for solar cells. 相似文献
84.
Ontiveros-Martínez Mdel R Ochoa-Martínez LA González-Herrera SM Delgado-Licon E Bello-Pérez LA Morales-Castro J 《Journal of food science》2011,76(9):C1278-C1283
As an alternative on the search for functional food products, this study evaluated the use of sourdough in the preparation of wheat flour tortillas. The sourdough was elaborated with Lactobacillus sanfranciscensis and the wheat flour tortillas were prepared with different concentrations of mother sponge (5%, 15%, and 25%) and fermentation times (1 and 3 h) at room temperature (25 ± 2 °C). Quality (diameter, height, color, pH, stretchability scores, and Kramer shear cell results) of wheat tortillas was evaluated after 24 h of preparation. The mother sponge concentration and fermentation time affected some quality parameters and acceptability properties (taste, aroma, color, opacity, and rollability). In addition, the sourdough tortillas had higher stretchability values than control tortillas. Since most of the prepared sourdough tortillas had acceptability values similar to those of tortilla controls, the introduction of sourdough is a viable means to incorporate additional nutritional and nutraceutical value into wheat tortillas. 相似文献
85.
Rosendo PEA-EGUILUZ Jos A LPEZ-FERNNDEZ Antonio MERCADO-CABRERA Bethsabet JARAMILLO-SIERRA Rgulo LPEZ-CALLEJAS Benjamn RODRGUEZ-MNDEZ Ral VALENCIA-ALVARADO Allan A FLORES-FUENTES Arturo E MUOZ-CASTRO 《等离子体科学和技术》2017,19(7)
A new configuration of a resonant full-bridge flying capacitor multicell inverter has been designed and constructed with the aim of achieving an extended output voltage frequency range with low harmonic distortion and reduced semiconductor commutation losses. This configuration was tested as a power supply for two different coaxial dielectric barrier discharge reactors, one of them employed for electric characterization and the other one for inorganic compound elimination in an aqueous solution. Two different gas mixtures, 90% Ar–10% O_2 and80% Ar–20% O_2, were individually supplied during the experiments; the results showed a highefficiency removal of meta-cresol(m-cresol) to the order of 98%, which was obtained by adding more oxygen to the plasma gas mixture. 相似文献
86.
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
87.
Arturo B. Soro Paul Whyte Declan J. Bolton Brijesh K. Tiwari 《Comprehensive Reviews in Food Science and Food Safety》2020,19(4):1353-1377
Campylobacteriosis is one of the most common bacterial infections worldwide causing economic costs. The high prevalence of Campylobacter spp. in poultry meat is a result of several contamination and cross‐contamination sources through the production chain. Moreover, survival mechanisms, such as biofilm formation, viable but nonculturable state, and antimicrobial resistance, enable its persistence during food processing. Therefore, mitigation strategies are necessary in order to avoid and/or inactivate Campylobacter at farm, abattoir, industry, and retail level. In this review, a number of potential strategies and novel technologies that could reduce the prevalence of Campylobacter in poultry meat have been identified and evaluated to provide a useful overview. At farm level for instance, biosecurity, bacteriocins, probiotics, feed and water additives, bacteriophages, and vaccination could potentially reduce colonization in chicken flocks. However, current technologies used in the chicken slaughter and processing industry may be less effective against this foodborne pathogen. Novel technologies and strategies such as cold plasma, ultraviolet light, high‐intensity light pulses, pulsed electric fields, antimicrobials, and modified atmosphere packaging are discussed in this review for reducing Campylobacter contamination. Although these measures have achieved promising results, most have not been integrated within processing operations due to a lack of knowledge or an unwillingness to implement these into existing processing systems. Furthermore, a combination of existing and novel strategies might be required to decrease the prevalence of this pathogen in poultry meat and enhance food safety. Therefore, further research will be essential to assess the effectiveness of all these strategies. 相似文献
88.
Daniela J. López‐Araujo Arturo Zavala‐Río Víctor Santibáñez Fernando Reyes 《International Journal of Adaptive Control and Signal Processing》2015,29(2):180-200
In this work, a generalized adaptive scheme for the global motion control of robot manipulators with constrained inputs is proposed. It gives rise to various families of bounded adaptive controllers defined through a general class of saturation functions. Compared with adaptive tracking control algorithms previously developed in a bounded input context, the proposed adaptive approach guarantees the motion control objective for any initial condition, avoiding discontinuities throughout the scheme, preventing the inputs to reach their natural saturation bounds, and permitting innovation on the saturating structure through its generalized form, giving a wide range of possibilities for performance improvement. Experimental results corroborate the efficiency of the proposed scheme. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
89.
A review of Internet Effectively: A Beginner's Guide to the World Wide Web by Tyrone Adams and Sharon Scollard. 相似文献
90.
Alicia B Pomilio Silvia P Trajtemberg Arturo A Vitale 《Journal of the science of food and agriculture》2005,85(4):622-628
Micellar electrokinetic capillary chromatography (MECC) experimental conditions were applied to 12 samples of methylxanthine‐containing infusions of different commercial brands of yerba mate, coffee, tea and cocoa as well as two cola drinks. The best resolution in this mode of automated high‐performance capillary electrophoresis (HPCE) was achieved here when using 15 kV voltage in an uncoated fused‐silica capillary of 45 cm length (40 cm effective length), 50 mM sodium dodecylsulfate, 90 mM pH 8.5 borate buffer and UV detection. Theobromine, caffeine and theophylline were separated, and the peak splitting due to tautomeric species was observed. Experimental conditions were controlled, keeping constant the size of the elution window in each analysis. The limit of detection was less than 1 mg l?1, the limit of quantitation was 2.5 mg l?1 and the work range was 2.5–300 mg l?1. This HPCE–MECC system has proved suitable for the analysis/quality control of xanthines in beverages for consumption. Roles of various parameters as well as distinctly charged species of each xanthine and the origin of peak splitting in this MECC system are discussed. Copyright © 2004 Society of Chemical Industry 相似文献