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61.
K. Habib 《Journal of Failure Analysis and Prevention》2010,10(5):427-433
The temperature versus thermal deformation (strain) with respect to time, of different coating films was studied by a non-destructive
technique (NDT) known as shearography. The behavior of organic coatings, i.e., epoxy, a white enamel, or a yellow acrylic
lacquer on carbon steels, was investigated at a temperature range simulating the severe weather temperatures in Kuwait especially
20–60 °C differences between the daylight and the night time temperatures. The investigation focused on determining the in-plane
displacement of the coatings, which amounts to the thermal deformation that results from the applied temperature range. Furthermore,
the investigation also focused on determining the thermal expansion coefficients of coatings and the slope of the plot of
the thermal deformation versus the applied temperature range. A critical (steady state) value of the thermal expansion coefficients
of coatings was used to determine the integrity of the coatings with respect to time. This value was determined from the decreasing,
time-dependent value of the thermal expansion coefficients of coatings. In fact, determination of critical (steady state)
value of the thermal expansion coefficients of coatings could be accomplished independent of parameters such as UV exposure,
humidity, presence of chemical species, and other parameters normally considered in conventional methods of the assessing
of the integrity of coatings. By using the technique of shearography, one needs only to determine the critical (steady state)
value of the thermal expansion coefficients of coatings, regardless of the history of the coating, in order to assess the
integrity of coatings. These results indicate that the technique is a very useful NDT method for determining the critical
value of the thermal expansion coefficients of different coatings and can be used as a 2D-microscope for monitoring the deformation
of the coatings in real-time at a submicroscopic scale. 相似文献
62.
Depiction of precipitation change by elevation in an areaindicates the possibilities of orographic rainfall occurrencesin the mountainous regions. In general, precipitation increaseswith elevation but sometimes inverse cases occur locally due toorographic and meteorological features of the area. Inpractice, prior to any quantitative modeling, qualitativeassessments and interpretations help to have sound foundationsin search for a suitable model. In this article, standardizedpoint cumulative semivariogram (SPCSV) methodology is employedfor identification of the precipitation-elevationrelationship. According to relative positions of theprecipitation and elevation SPCSVs four different precipitationcategories are suggested. The application of the methodologyproposed is presented for the precipitation records from YuccaMountain, Nevada, U.S.A. 相似文献
63.
Amir Daraei Garmakhany Habib Ollah Mirzaei Dr. Mahdi Kashani Nejad Yahya Maghsudlo 《European Journal of Lipid Science and Technology》2008,110(11):1045-1049
The use of coating agents is one effective way to reduce oil absorption in fried products. Reducing the fat content of fried foods by application of coatings is an alternative solution to comply with both health concerns and consumer preferences. The aim of this study was to analyze the effect of hydrocolloids as coating agent on the quantity of oil uptake and on sensory attributes of potato chips. The effect of the coating composition showed that the minimum fat content was related to 1% carboxymethyl cellulose (CMC), 0.5% xanthan, 0.3% guar and 1% xanthan with 21.2, 21.7, 22.4 and 24.8%, respectively, and the highest of fat content was related to blank sample (non-coated), 2% tragacanth, 0.5% guar gum with 49.4, 41.7 and 33.2% of oil content, respectively (p <0.05). The most effective coating agent reduced the oil uptake by 57.03, 55.94, 54.67 and 49.71%, respectively (p <0.05). Sensory evaluation showed that the best color was related to 1% CMC, 0.3% guar and 2% tragacanth, and with respect to flavor evaluation the best flavor was observed in tragacanth 2%, CMC 0.5% and CMC 0.1%, and the best texture referred to tragacanth 2%, CMC 0.5% and CMC 1%. In sensory evaluation, all coated chips got high scores compared with blank (non-coated chips) samples (p <0.05). 相似文献
64.
65.
The kinetics of growth of Al2O3 oxide films made by anode oxidation of ALuminium 1050A with two anodization techniques has been investigatedan compared. The first technique is the classical method based on continuous tension during the complete electrlysis duration, and the second one is the modern method ofpulsed tensions, whcih consists of periodically imposing to the material two anodc tensions E1 and E2 (E1 > E2) during time T1 and T2 until the end on anodization. We have shown that the second technique allows the fabrication of films more rapidly for the same electrolysis duraton. Energy and electrolysis time are saved, making it attractive from an economical viewpoint. This advantage arises from the positive effect of excess heat disiption gathered during the imposition of tension, E1, when E2 is imposed thereafter (recovery effect). The logging of in situ transient responses in the case of pulsed anodization is a significant asset to explain the growth film kinetics obtained with this method. 相似文献
66.
67.
The influence of certain stabilizers on the aerobic photobleaching of buffered riboflavin phosphate solutions exuosed to fluorescent light was investigated. Disodium ethylenediamine (EDTA) demonstrated the greatest stabilizing effect followed by thiourea, methyl paraben, DL-methionine and sodium thiosul fate. The photostabilizing effect of these agents increased as their concentrations increased. Other stabilizers enhanced the photostability of riboflavin solutions with lesser and varying degrees. The pH and buffer species of the solutions appared to infulence the rate of photodegradation of riboflavin solutions in the presence of absence of EDTA. 相似文献
68.
Mohammad Mazaheri Yousef S. Kavian Hamid Sharif Habib F. Rashvand 《Wireless Communications and Mobile Computing》2016,16(15):2406-2418
Because of the practical limitations of the energy and processing capabilities, the deployment of many Wireless Sensor Networks (WSN) is facing two main challenges of increasing network lifetime and reducing End to End Delay (EED) which become critical when the nodes are mobile and use non‐rechargeable energy sources. One way to help to extend network lifetime is using fuzzy logic in a form of artificial intelligence. To this end we propose a new routing protocol for using mobile WSNs, which holds the nodes in an equal level of energy and decreases energy dissipation of the network. An optimum path is selected based on the cost of each node to increase network lifetime. In order to lessen EED, we also attempt to design a novel zoning‐scheme for the network area. In this scheme, zonation is dynamic and works based on the Data Link (DL) position. The simulation result shows a significant improvement in lifetime and EED by proposed protocol compared with existing protocols. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
69.
This paper reports the use of a carbon ceramic electrode as a highly-porous substrate for the electrochemical formation of cobalt oxide nanoparticles. The electrocatalyst was characterized by energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM) and cyclic voltammetry techniques, and it was used in a homemade flow injection analysis (FIA) system for acetaminophen determination using 0.1 M KOH as the carrier solution. The rate constant (ks) and charge transfer coefficient (α) were calculated for the electron exchange reaction of the modified film. The kinetic parameters and the mechanism of acetaminophen electrooxidation at the electrode surface were studied by cyclic voltammetry and chronoamperometry. The effects of working potential and flow rate on the performance of the FIA system were studied. Under optimized conditions, the electrode response due to the electrocatalytic oxidation of acetaminophen at 450 mV (vs. SCE) is proportional to the concentration of acetaminophen over a 5-35 μM range with an associated detection limit (S/N = 3) of 0.37 μM and a sensitivity of 0.0296 μA/μM. The relative standard deviation (RSD) was 1.6% for eight replicate measurements. The modified electrode was used to determine the acetaminophen content in tablet samples. 相似文献
70.
Habib Firouzabadi Nasser Iranpoor Mohammad Gholinejad 《Advanced Synthesis \u0026amp; Catalysis》2010,352(1):119-124
In this article, we have developed a new protocol for the thioarylation of structurally diverse alkyl bromides such as benzyl, cinnamyl, n‐octyl, cyclohexyl, cyclopentyl, and tert‐butyl bromides with aryl iodides, bromides and an activated chloride using thiourea catalyzed by copper(I) iodide in wet polyethylene glycol (PEG 200) as an eco‐friendly medium in the presence of potassium carbonate at 80 and 100 °C under an inert atmosphere. The process is free from foul‐smelling thiols which makes this method more practical for the thioetherification of aryl halides. Another important feature of this method is the variety of alkyl bromides which are commercially available for the in situ generation of thiolate ions with respect to the existing protocols in which the less commercially available thiols are directly used for the preparation of arylthio ethers. 相似文献