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61.
It is shown by contactless transient photoconductivity measurements in the microwave frequency range that Si3N4 films are an outstanding passivation of the n-type c-Si surface. Si3N4 on n-type Si forms an accumulation layer, which acts as an ideally reflecting potential barrier for minority carriers (holes). Due to the small space charge layer capacitance, minority carrier storage at this interface is very limited.In contrast to the latter measurements on p-type Si wafers covered with Si3N4 are characterized by storage of excess charge carriers in the surface depletion layer. The stored charge carriers decay slowly. The minority carriers (electrons) collected at the surface show a reduced mobility. 相似文献
62.
Mohamad Khawlie Amin Shaban Chadi Abdallah T. Darwish Issam Kawass 《Lakes & Reservoirs: Research and Management》2005,10(2):85-92
Integrated watershed assessment, especially relying on remote sensing (RS), is a newly established procedure in developing countries. It is proving to be a major component in river‐basin environmental management. The recurrence of environmental problems in the Akkar El Kabir River watershed, as well as the lack of proper data on sources and sinks of pollutants, and the extent of human interference, led to the current study. Advanced geoinformation tools, such as RS and geographical information systems (GIS), prove to be a valuable asset in securing data on the fabric of the Akkar watershed in relation to its natural setting and anthropic interference. This is particularly true in the current study as the river constitutes the boundary between Lebanon and Syria. Remote sensing captures the watershed characteristics and land use on both sides without constraints. The natural fabric includes geology, drainage, hydrogeology, forest and soil. The anthropic fabric includes settlements, utilities, roads, agriculture and land use. If it were not for geoinformation techniques, the task of securing such data would be difficult. Also, these techniques show the impact of malpractices from excessive human interference that result in degradation of land and water quality. Changes in the watershed, such as environmental deterioration, are observed as water pollution, soil erosion, forest decline and socioeconomic imbalance. Obviously, this is the outcome of malpractices in a multisectorial system. A major challenge for RS and GIS is to quantify, model and predict, if possible, the extent of these changes. Remote sensing inherently captures the impact of interaction between nature and human beings. Detection of change is a major indicator that RS can contribute to the evaluation of the state of the environment. The application of it on this watershed reveals that significant changes have occurred over the last 10–15 years, most of which are anthropic. 相似文献
63.
F. M. Al-Nowaiser M. Abdallah E. H. El-Mossalamy 《Chemistry and Technology of Fuels and Oils》2011,47(1):66-74
The possibility of using rosemary oil as a corrosion inhibitor of carbon steel in 0.5 M sulfuric acid solution was investigated
by determination of weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. It was shown that
the inhibition effectiveness increases with an increase in the concentration of oil and a decrease in the temperature. The
inhibiting effect of the investigated oil is due to its adsorption on the surface of the steel and complexation. Adsorption
is described by a Langmuir isotherm. The effect of the temperature on the corrosion rate was studied in the presence and absence
of the oil and the thermodynamic parameters of the corrosion process were calculated. 相似文献
64.
Said S. Ibrahim Ferial M. Abu Salem M. A. Abdallah 《Molecular nutrition & food research》1975,19(3):207-211
In this study processed mango juice was packed in four types of containers and stored at different temperatures for 16 weeks through which furfural level determination and organoleptic assessment were conducted. The experiment revealed an evident relationship to exist among furfural level, storage temperature and type of packing material. Furfural level failed to closely parallel flavour difference; therefore it could be regarded as one of the features concomitant juice aging rather than accepted as a satisfactory criterion of off flavour. The study relates flavour deterioration to the changes in the lipid fraction of the juice. 相似文献
65.
M. A. Saad Aida H. S. H. Abu-El-Zahab A. Abdallah S. F. El-Sisi 《Molecular nutrition & food research》1993,37(6):553-560
Adult male albino rats were supplemented with edible plant oils, corn maize and cotton seed oils and their semihydrogenated forms (Heliopolis and Sultan cooking fats) for a period of 3 months. In general, the supplementation of tested oils produced increasing effect on the serum levels of total C18: 1, C18:2 and C20:4 unsaturated fatty acids (UFA). The increases were significant in case of feeding corn maize oil and Sultan cooking fat for total and C18: 1 and C18:2 UFA. However, the degree of significance was intensified by the feeding of cotton seed oil and Heliopolis cooking fat. Supplementation of Sultan cooking fat showed a significant increase in serum level of C20:4, while the other tested oils and Heliopolis cooking fat produced very highly significant increase. Butylated hydroxy anisol (BHA) produced no effect on the level of UFA when administered with dietary tested edible lipid but its role revealed by maintaining the higher level of UFA due to administration of oils and its semihydrogenated analogous. 相似文献
66.
AA Wahib AA Masoud AA Halem AN Haseeb AR Hassan MA Darwish M Hegazi KF Abdallah 《Canadian Metallurgical Quarterly》1998,28(3):929-939
Cell mediated immune response (CMIR) was studies in 120 patients having chronic liver diseases. Patients were divided into 6 groups, (20 each). (1) Early hepatosplenic Schistosomiasis. (EHSS), (2) Late hepatosplenic Schistosomiasis. (LHSS), (3) Hepatosplenic Schistosomiasis with hepatitis B and/or C infections, (4) Hepatitis B virus cases. (HBV), (5) Hepatitis C virus cases (HCV), (6) Hepatocellular carcinoma cases. (HCC). Twenty within normal subjects taken as controls. Laboratory investigations revealed significant esinophilia in patients of group (1), haemoglobin level was significantly reduced in patients of group (1, 2, 3, & 6), serum albumin was significantly reduced in group (2). The percentage of positivity of skin testing using purified protein derivative, ranged between 10% of patients with LHSS, HBV, HCC and HSS with HBV and/or HCV, 20% of patients with HCV and 25% of patients with EHSS. Percentage of positivity in control group was 100%. The mean diameter of delayed intradermal reaction (2.2 +/- 0.5-6.1 +/- 2.1 mms.) was significantly lower in patients than controls. The response of lymphocyte transformation test to phytohaemmagglutinin was significantly lower in patients when compared to controls. The association of HBV and/or HCV with hepatosplenomegaly was accompanied with a marked depression in cell mediated immune response. Anaemia, hypoalbuminemia and nutritional status of the patients with chronic liver diseases play a major role in the suppression of cell mediated immune response. 相似文献
67.
Petroleum coke (petcoke) is a challenging fuel in terms of its complexity, high sulphur and nitrogen content, low volatile content, and undesirable emissions of SOx and NOx when used for power generation. To overcome these challenges, the oxy‐cracking process was recently proposed to convert the petcoke into a clean combustion fuel by reducing its sulphur and nitrogen contents, and consequently increasing its reactivity and combustibility. This work aimed to study the heating values and thermo‐oxidative behaviour of the oxy‐cracked petcoke, virgin petcoke, and their blends using thermogravimetric analysis (TGA). The results showed that the oxy‐cracked petcoke is oxidized at a temperature of 475 °C, which is easier and faster than the virgin petcoke, which is usually oxidized at around 540 °C. The heating value of the oxy‐cracked petcoke was not impacted and maintained constant ~30 MJ/kg, which is relatively similar to the virgin petcoke. The nitrogen and sulphur content in the oxy‐cracked petcoke is much lower than that of virgin petcoke. A significant improvement in the combustion performance parameters of the oxy‐cracked petcoke and their blends with virgin petcoke was achieved. For instance, the ignition temperature of the proposed fuel is reduced to 13 % compared to the virgin petcoke, which led to increasing the ignition index by two‐folds. Therefore, this approach might help in improving the thermal efficiency of petcoke by using oxy‐cracked products as an initiator in the combustion process. 相似文献
68.
Abdallah M. Altass H. M. El-Sayed R. Al Gorair Arej S. Jahdaly B. A. AL Sobhi M. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(4):811-819
Protection of Metals and Physical Chemistry of Surfaces - Three nonionic surfactants molecules (NS) derived from a fused pyridine characterized by IR and 1HNMR spectra were synthesized and examined... 相似文献
69.
Pattern Analysis and Applications - This paper presents a reliable and real-time method to detect pedestrians in image scenes that can vary greatly in appearance. To achieve greater reliability in... 相似文献
70.
Rim Ben Abdallah Ana Belén Bautista-Ortin Tesnime Ghazouani Wafa Talbi Maria D. Jiménez-Martinez Encarna Gómez-Plaza Sami Fattouch 《International Journal of Food Science & Technology》2019,54(5):1633-1641
During technological processing, proanthocyanidins and anthocyanidins could be partly lost due to the complexation phenomena, affecting food and beverage nutritional properties, organoleptic properties and health-promoting potentials. A common issue is encountered when processing food and beverage which is binding of phenolics to dietary proteins. The present investigation aims at evaluating the proteolysis contribution, using pure protease (Pepsin, 3000 units g−1), to protein–anthocyanidin and protein–proanthocyanidin interactions. Bovine serum albumin (BSA), ovalbumin (OVA) and casein (CAS) dietary protein models were used. High-performance liquid chromatography coupled to diode array detector (HPLC-DAD) and size exclusion chromatography analyses proved that pepsin treatment significantly (P > 0.05) decreased the ratio of flavonoids’ interaction with tested proteins . The proteolysis reduced anthocyanidin interactions with CAS, OVA and BSA by 64.88%, 57.37% and 42.87% respectively. Similarly, proanthocyanidins interaction with CAS, OVA and BSA were reduced by 34.23%, 13.74% and 2.39% respectively. This study provides the basis to develop innovative technologies to limit protein–flavonoid complexation during food and beverage processing. 相似文献