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991.
Mustafa Iik Delia Teresa Sponza 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(11):1268-1274
The treatment of a wastewater taken from a cotton textile mill was investigated using an anaerobic/aerobic sequential system during an operational period of 87 days. The process units consisted of an upflow anaerobic sludge blanket (UASB) reactor and a continuous stirred tank reactor (CSTR). Wastewater characterization was performed before feeding the reactor system. Glucose‐COD, and azo dyes were added to the textile wastewater for comparative purposes in the final period of operation. The pH values in the effluent of the UASB reactor were suitable for optimal anaerobic treatment in all runs. The biodegradable part of the COD in wastewater was removed effectively, with the anaerobic stage improving the biodegradability of wastewater entering the aerobic stage. The UASB reactor permitted COD and color removals of 9–51% and 46–55%, respectively, at a hydraulic retention time (HRT) of 30 h. COD removal efficiencies were between 40 and 85% and color removal efficiencies were 39–81% in normal and artificially‐colored wastewaters at a total HRT of 5.75 days in the UASB/CSTR reactor system. Benzidine produced from the cleavage of azo bond in the anaerobic stage was effectively removed in the aerobic stage, and was identified by comparison of its HPLC spectrum with that of an authentic specimen. Copyright © 2004 Society of Chemical Industry 相似文献
992.
J. Mustafa M. T. Saeed S. M. Osman 《Journal of the American Oil Chemists' Society》1991,68(5):313-314
A quantitative preparation of bisoxathiolane from 9,12-dioxo-trans-10-octadecenoic acid is discussed. The reagents used are β-mercaptoethanol and BF3− etherate in acetic acid. The structure of the product was established with the help of elemental analysis, infrared, nuclear
magnetic resonance and mass spectroscopy data. 相似文献
993.
Mustafa Übeyli 《Journal of Fusion Energy》2006,25(1-2):67-72
Using liquid wall between the plasma and solid first wall in a fusion reactor allows to use high neutron wall loads and could eliminate frequent replacement of the first wall structure during reactor’s lifetime. Liquid wall should have a certain effective or optimum thickness to extend solid first wall lifetime to reactor’s lifetime and supply sufficient tritium for deuterium–tritium (DT) fusion driver. This study presents the effect of thickness of flowing liquid wall containing 90 mol % Flibe+10 mol % UF4 or ThF4 on the neutronic performance of a magnetic fusion reactor design called APEX. Neutron transport calculations were carried out with the aid of code Scale4.3. Numerical results brought out that optimum liquid wall thickness of ∼38 cm was found for the blankets using Flibe+10% UF4 whereas, 56 cm for that with Flibe+10% ThF4. Significant amount of high quality fissile fuel was produced by using heavy metal salt. 相似文献
994.
Mustafa E. Tat Joh H. Van Gerpen 《Journal of the American Oil Chemists' Society》2003,80(11):1127-1130
The density and speed of sound of blends of biodiesel with No. 2 and No. 1 diesel fuels were measured from atmospheric pressure
to 32.46 MPa at temperatures of 20 and 40°C. The isentropic bulk modulus was calculated from these quantities. The results
show that the density and isentropic bulk modulus can be accurately modeled as having a linear variation with blend percentage.
Speed of sound is better correlated by a second-order equation. Correlation equations are given and a blending rule is developed
that allows the density, speed of sound, and isentropic bulk modulus of blends to be calculated from the properties of the
biodiesel and diesel fuel. 相似文献
995.
Powder coatings, which are made by plasma‐spraying processes, are being used in industrial applications because of their wear resistance, chemical resistance, and high impact strength even at low service temperatures. These factors increase the importance of plastic and plastic‐based coatings in industrial applications. In this study, an aluminum–silicon–polyester‐based composite coating was applied by plasma‐spraying processes with and without an intermediate bond coat (Ni–Al). The effects of the coating thickness, intermediate bond coat, and processes parameters on the microstructure and wear properties of the coating were studied experimentally. The wear properties of the coatings were determined according to ball‐on‐disk procedure. The microstructures of the coating were examined by optical microscopy and scanning electron microscopy. The results indicated that the plasma‐spraying current and thickness had a strong influence on the wear resistance and microstructural properties of the aluminum–silicon–polyester coating. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3609–3614, 2006 相似文献
996.
The selection of a cost-minimizing combination of hardware and network components of Internet-based systems to satisfy organizational requirements is a complex design problem with multiple degrees of freedom. Decisions must be made on how to distribute the overall computing load onto multiple computers, where to locate computers and how to take advantage of legacy components. The corresponding optimization problem not only embeds the structure of NP-hard problems, but also represents a challenge with a well-structured heuristic approach.A scientific approach has been rarely applied to cost minimization and a rigorous methodological support to cost issues of the design of Internet-based distributed systems is still lacking. The methodological contribution of this paper is the representation of complex design issues as a set of four intertwined cost-minimization sub-problems: two set-partitionings, a set-packing and a min k-cut with a non-linear objective function. Optimization is accomplished by sequentially solving these sub-problems with a heuristic approach and tuning their solution with a local-search approach. Results indicate that decomposition significantly reduces optimization time and solutions have also lower costs than those identified without prior decomposition (20-60%). Cost reductions considerably grow (25-70%) when methodological outputs are compared with practitioners’ solutions. 相似文献
997.
Danilo Montesi 《Knowledge》1996,9(8):809-507
Heterogeneous knowledge representation allows combination of several knowledge representation techniques. For instance, connectionist and symbolic systems are two different computational paradigms and knowledge representations. Unfortunately, the integration of different paradigms and knowledge representations is not easy and very often is informal. In this paper, we propose a formal approach to integrate these two paradigms where as a symbolic system we consider a (logic) rule-based system. The integration is operated at language level between neural networks and rule languages. The formal model that allows the integration is based on constraint logic programming and provides an integrated framework to represent and process heterogeneous knowledge. In order to achieve this we define a new language that allows expression and modelling in a natural and intuitive way the above issues together with the operational semantics. 相似文献
998.
M. Tugrul Sezer Ibrahim Eren Ramazan Ozcankaya Ikbal Civi Jale Erturk Mustafa Ozturk 《Hemodialysis international. International Symposium on Home Hemodialysis》2003,7(4):332-337
Background: The purpose of this study was to evaluate and compare psychosocial characteristics in caregiving relatives (caregivers) of hemodialysis (HD) and peritoneal dialysis (PD) patients. Methods: Thirty‐three caregivers (17 women, 16 men) of HD patients, 27 caregivers (11 women, 16 men) of PD patients, and a control group of 49 subjects who do not care for family members with chronic illness (23 women, 26 men) are included in this study. The brief symptom inventory (BSI), social disability schedule (SDS), and brief disability questionnaire (BDQ) were used for the psychosocial evaluation. Results: The mean age, men‐to‐women ratios, duration of education, and distribution of marital status did not differ significantly among the three groups. In addition, dialysis duration and distribution of caregiver type were not different between the HD and PD groups. Although the mean global severity index scores of the three groups were similar, somatization and depression scores from BSI subitems were greater in the HD group than the scores of the PD and control groups. Although the mean SDS and BDQ scores were higher in the HD group, the differences did not achieve statistical significance. BSI subitems such as somatization, obsession–compulsion, interpersonal sensitivity, depression, and anxiety were positively correlated among themselves. Hostility and somatization were negatively correlated with age and education, respectively. Nevertheless, somatization was positively correlated with age. Social disability was negatively correlated with duration of education. Conclusion: Somatization and depression are greater in the caregivers of center HD patients compared to PD and control groups. According to the findings of this study, we suggest that caregiving family members of dialysis patients especially on HD also should be evaluated for psychosocial problems and supported as needed. Further studies are needed to explore whether psychosocial parameters of caregivers predict outcomes for caregivers and patients. 相似文献
999.
The analysis of the reasons causing degradation observed in resist layer during selective gold plating on patterns for MIC's has resulted in an excellent combination of electrolytic bath and photoresist type. Thick layers of gold (i.e. more than 10 μm) have been deposited by the method presented here over a period of about 1 h without any deterioration in the photoresist property. This combination can be used in the fabrication of beam lead devices with better results. 相似文献
1000.