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81.
82.
Li Jinyan Fong Simon Liu Lian-sheng Dey Nilanjan Ashour Amira S. Moraru Luminița 《Multimedia Tools and Applications》2019,78(15):20913-20933
Multimedia Tools and Applications - The imbalance and multi-dimension are two common problems in the medical image datasets, which affect the performances of the image processing procedures. The... 相似文献
83.
Zenat A. Nagieb Samia M. Helmy Amira El-Gammal 《Polymer-Plastics Technology and Engineering》2013,52(4):457-464
Pretreatment of wood chips with some microorganisms including white-rot fungi and streptomyces improves the strength properties of mechanical pulps. We studied the effect of these white-rot fungi and streptomyces on the mechanical properties of handsheets. Strength and optical properties were compared in handsheets prepared from mechanical pulp of treated and untreated wood chips. The fungal pretreatments resulted in handsheet strength properties better than the control and also better than streptomyces when compared at an equivalent freeness. Fungal pretreatments decreased brightness and light-scattering coefficients but did not adversely affect opacity. Lignin content of the chips was reduced by fungal pretreatments. 相似文献
84.
Reinforcement of polyolefins‐based nanocomposites: combination of compatibilizer with high shear extrusion process 下载免费PDF全文
Amira Bouaziz Valérie Massardier Molka Louizi Mohamed Jaziri 《Polymer Engineering and Science》2015,55(10):2328-2338
The structure and properties of polypropylene (PP) and ethylene propylene copolymer (EPR) blends filled with nanosilica have been investigated. The nanocomposites were prepared via direct melt mixing using high shear corotating twin screw extruder. The effects of the process as well as adding amaleated‐Polyethylene MAPE compatibilizer were assessed by morphology studies, thermal analysis and mechanical testing. From SEM and TEM investigations, a separate dispersion of filler and rubber in the PP matrix prevails in the PP/EPR/SiO2 systems. Encapsulation of the filler particles into the elastomer takes place when MAPE is used, promoting filler/polymer interactions and resulting in a simultaneous improvement in stiffness and toughness. Interestingly, the results indicated that high‐shear processing is an effective method to improve the dispersion of the EPR phase and fillers through the matrix. The dispersed phase droplet size was reduced with the increase of the shear rate by varying the screw rotation speed from 300 to 800 rpm, which induces a high shear stress exerted onthe materials. To sum up, what is expected from an efficient compatibilization‐process association is the reduction of the dispersed elastomer domains characteristic size, their stabilization by creation of an interphase and thus, enhanced mechanical properties. POLYM. ENG. SCI., 55:2328–2338, 2015. © 2015 Society of Plastics Engineers 相似文献
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The purpose of this paper is to highlight the relationships between housing, food security, and health. We begin by reviewing the current literature on the intersections of housing and food security, emphasizing the current gaps in knowledge in the areas of building infrastructure, in-house food programs, and building context for social housing. Derived from the literature review, we present a model designed to highlight the relationships between food, housing, and health. Following this, we provide a case study of housing and food security for residents of the Downtown Eastside. By examining the experiences of residents struggling to find both food and shelter within a very low-income context, we underscore the ways in which food, health, and housing intersect. We conclude by outlining future research directions that will enhance understanding of these intersections. 相似文献
87.
Dhouha Krichène Amira Allalout Maria D. Salvador Giuseppe Fregapane Mokhtar Zarrouk 《European Journal of Lipid Science and Technology》2010,112(3):400-409
Fatty acids, volatiles, sterols, aliphatic and triterpenic alcohols of six monovarietal Tunisian virgin olive oils were analyzed. The results suggested that the compositional data concerning the above analytical fractions were effective in discriminating between varieties. The oils were found to contain high levels of oleic acid (up to 71.70% in the Oueslati variety). β‐Sitosterol (up to 85.46% in the Jdallou variety) and Δ5‐avenasterol (up to 30.97% in the El Hor variety) were the principal sterols in all samples; campesterol and stigmasterol were found at low levels. (E)‐2‐Hexenal was the main compound that characterizes the olive oil headspace of all samples. The other compounds identified were mainly C6 aliphatic components. 相似文献
88.
Balamatsia CC Rogga K Badeka A Kontominas MG Savvaidis IN 《Journal of food protection》2006,69(5):1126-1133
The effect of gamma-radiation (0.5, 1, and 2 kGy) on the shelf life of fresh skinless chicken breast fillets stored aerobically at 4 degrees C was evaluated. Microbiological, chemical, and sensorial changes occurring in chicken samples were monitored for 21 days. Irradiation reduced populations of bacteria, i.e., total viable bacteria, Brochothrix thermosphacta, lactic acid bacteria (LAB), and the effect was more pronounced at the highest dose (2 kGy). Pseudomonads, yeasts and molds, and Enterobacteriaceae were highly sensitive to gamma-radiation and were completely eliminated at all doses. Of the chemical indicators of spoilage, thiobarbituric values for nonirradiated and irradiated aerobically packaged chicken samples were in general low (<1 mg of malonaldehyde per kg of muscle) during refrigerated storage for 21 days. With regard to volatile amines, both trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N) values for nonirradiated aerobically packaged chicken increased steeply, with final values of ca. 20.3 and 58.5 mg N/100 g of muscle, respectively. Irradiated aerobically packaged chicken samples had significantly lower TMA-N and TVB-N values (P < 0.05) of ca. 2.2 to 3.6 and 30.5 to 37.1 mg N/100 g of muscle, respectively, during refrigerated storage for 21 days. Of the biogenic amines monitored, only putrescine and cadaverine were detected in significant concentrations in both nonirradiated and irradiated chicken samples, whereas histamine formation was noted only in nonirradiated samples throughout storage. On the basis of sensorial evaluation, low-dose irradiation (0.5 and 1.0 kGy) in combination with aerobic packaging extended the shelf life of fresh chicken fillets by ca. 4 to 5 days, whereas irradiation at 2.0 kGy extended the shelf life by more than 15 days compared with that of nonirradiated chicken. 相似文献
89.
Keith R. McIntosh Ganokwan Boonprakaikaew Christiana B. Honsberg 《Solar Energy Materials & Solar Cells》2000,64(4):353
The inclusion of a floating junction (FJ) at the surface of a solar cell is one way to obtain good-quality surface passivation. The development of FJ-passivated solar cells, however, has been hindered by the frequent occurrence of shunting across the FJ. Shunting can occur at specific regions of the FJ, such as at isolated points of the base contact or at the edges of the solar cell. This paper presents an experimental technique to determine the shunt resistance across local regions of an FJ, thereby providing a means to compare the prevalence of shunting in one region to another. By locating and quantifying the shunting in specific regions of an FJ, valuable insight into its cause can be obtained. 相似文献
90.
Mnari Bhouri Amira Jrah Harzallah Hanene Dhhibi Madiha Bouhlel Imen Hammami Mohamed & Chaouch Abdelhamid 《International Journal of Food Science & Technology》2010,45(1):113-123
The effects of frying in soybean (FWSO) and olive oils (FWOO) on the fatty acid composition of farmed and wild gilthead sea bream Sparus aurata were evaluated. The fat content increased with both frying treatments. However, after FWOO the moisture content of the fish was reduced to a greater extent than that in fish FWSO. The concentration of saturated fatty acids (SFA) decreased significantly during both frying processes ( P < 0.01). However, the concentration of monounsaturated fatty acids (MUFA) increased significantly in fish fried in olive oil ( P < 0.01). The fried fish contained a higher level of n-6 polyunsaturated fatty acids (PUFA) and a lower level of n-3 PUFA compared to raw fish. The n-3/n-6 ratio decreased in wild fish FWSO and FWOO from 0.94 ± 0.08 to 0.15 ± 0.01 and 0.15 ± 0.02, respectively. In farmed bream, the ratios decreased from 2.51 ± 0.03 to 0.18 ± 0.03 and 0.36 ± 0.01, respectively. The concentration of trans fatty acids decreased significantly in both fish types after frying ( P < 0.05). The frying process widely affected the EPA and DHA content, limiting the positive effects of n-3 PUFA. 相似文献