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991.
Francisco J. Camacho‐Torregrosa Ana M. Pérez‐Zuriaga José M. Campoy‐Ungría Alfredo García Andrew P. Tarko 《Computer-Aided Civil and Infrastructure Engineering》2015,30(4):282-299
This article proposes a new method for fitting the horizontal alignment of a road to a set of (x, y) points. Those points can be obtained from digital imagery or GPS‐data collection. Unlike current methods that represent road alignment through its curvature, the proposed method describes the horizontal alignment as a sequence of headings. An analytic–heuristic approach is introduced. The proposed method produces unique solutions even for complex horizontal alignments. Some examples and a case study are presented. This solution may not be accurate enough for road redesign, but it allows researchers and departments of transportation to obtain accurate geometric features. 相似文献
992.
J. M. Macher M. J. Mendell K. Kumagai N. T. Holland J. M. Camacho K. G. Harley B. Eskenazi A. Bradman 《Indoor air》2016,26(6):892-902
Relationships between measured moisture and qualitative dampness indicators (mold odor, visible mold, visible water damage, or peeling paint) were evaluated using data collected from California homes in a prospective birth cohort study when the infants were 6 or 12 months of age (737 home visits). For repeated visits, agreement between observation of the presence/absence of each qualitative indicator at both visits was high (71–87%, P < 0.0001). Among individual indicators, musty odor and visible mold were most strongly correlated with elevated moisture readings. Measured moisture differed significantly between repeated visits in opposite seasons (P < 0.0001), and dampness increased with the number of indicators in a home. Linear mixed‐effect models showed that 10‐unit increases in maximum measured moisture were associated with the presence of 0.5 additional dampness indicators (P < 0.001). Bedroom (BR) walls were damper than living room (LR) walls in the same homes (P < 0.0001), although both average and maximum readings were positively correlated across room type (r = 0.75 and 0.67, respectively, both P < 0.0001). Exterior walls were significantly damper than interior walls (P < 0.0001 in both LRs and BRs), but no differences were observed between maximum wall readings and measurements at either window corners or sites of suspected dampness. 相似文献
993.
994.
Effect of Citrus paradisi and Ocimum sanctum Infusions on Blood Pressure Regulation and Its Association with Renal Alterations in Obese Rats 下载免费PDF全文
995.
This paper provides the profiling on the ??relative absorptive capacity of knowledge?? research to provide insights of the field based on data collected from the ISI Web of science database during the years 2001?C2010. The analysis is established in three phases, namely, the general publication, the subject area, and the topic profiling. The study obtains patterns, characteristics, and attributes at country, institutions, journals, author, and core reference levels. It shows the increase of the research activity in the field, based on the publication productivity during the years mentioned. Most of these publications are classified in the subject areas of business and economics, engineering, and operations research and management science. We highlight the nascent interest of the computer science subject area as a way to operationalize the different studies conducted. We found a lack of contribution from African and Latin?CAmerican countries despite the importance of the field for them. Our results are useful in terms of science strategy, science and technology policy, research agendas, research alliances, and research networks according to the special interest of specific actors at the individual, institutional, and national levels. 相似文献
996.
997.
I. Fernández García P. Montesinos E. Camacho Poyato J.A. Rodríguez Díaz 《Water Resources Management》2016,30(3):1085-1099
Network sectoring is one of the most effective measures to reduce energy consumption in pressurized irrigation networks. In this work, the previous model focused on the irrigation networks sectoring with several supply points (WEBSOM), which considered the simultaneous operation of all hydrants, has been improved by integrating an analysis of multiple random demand patterns and their effects on variability in hydrant pressure (extended WEBSOM). The extended WEBSOM has implied a multiobjective optimization, followed by a Montecarlo procedure to analyze different flow regimes using quality of service indicators, a novelty for multi-source pressurized irrigation networks. This innovation has involved energy savings ranging from 9 to 15 % with respect to the consideration of the concurrent operation of all hydrants, which rarely occurs in on-farm irrigation systems. These energy savings were associated with maximum values of pressure deficit of 21 and 34 % in the most critical hydrant with a deficit frequency of 27 and 36 % in the peak month. However, smaller and less frequent deficits were achieved in the rest of the months. Thus, substantial energy savings can be obtained in irrigation districts without significant losses in the service quality provided to farmers. 相似文献
998.
Designing a proportional derivative (PD) controller has as main problem, to obtain the derivative of the output error signal when it is contaminated with high frequency noises. To overcome this disadvantage, the supertwisting algorithm (STA) is applied in closed-loop with a PD structure for multi-input multi-output (MIMO) second order nonlinear systems. The stability conditions were analyzed in terms of a strict non-smooth Lyapunov function and the solution of Riccati equations. A set of numerical test was designed to show the advantages of implementing PD controllers that used STA as a robust exact differentiator. The first numerical example showed the stabilization of an inverted pendulum. The second example was designed to solve the tracking problem of a two-link robot manipulator. 相似文献
999.
C Cuadrado G Ayet C Burbano M Muzquiz L Camacho E Cavieres M Lovon A Osagie K R Price 《Journal of the science of food and agriculture》1995,67(2):169-172
Samples of bitter seeds of local ecotypes and cultivars of lupin (Lupin mutabilis), white and yellow ecotypes of quinoa (Chenopodium quinoa Wild) and a local ecotype of amaranth (Amaranthus caudatus) grown in the Peruvian highlands were analysed for total saponin content and sapogenol composition. Sweet cultivars of L albus and L luteus cultivated in mild-rainy lowlands of Chile were also analysed for comparison. Fast atom bombardment-mass spectrometry (FAB-MS) of the saponin extracts and gas chromatography (GC) analysis of the sapogenols after acid hydrolysis of the crude extract-were used for the identification and quantification of saponins. It was found that L albus and amaranth had undetectable levels of saponins making them attractive for human consumption. The cultivars and ecotypes of L mutabilis contained saponin levels in the range of 229.8–390.5 mg k?1. FAB-MS showed the presence of soya saponins I and II, whereas GC allowed the identification of soya sapogenols A and B. The same saponin composition was determined in L luteus whose total content was 55.3 mg kg?1. Saponin composition in quinoa seeds comprised oleanolic acid and three other sapogenols identified as hederagenin, phytolaccagenic acid and deoxyphytolaccagenic acid. Oleanolic acid saponins were found to be the main class of saponin in quinoa seeds sampled for this study. The yellow ecotype of quinoa presented a significantly higher content of saponins and of oleanolic acid as compared to white ecotypes. Since only one ecotype of amaranth was analysed, the nutritional significance of no detectable saponin needs further study. It was concluded that the environmental conditions in the Peruvian highlands are determinants of the amount and composition of saponins present in bitter lupine and quinoa. 相似文献
1000.
Manuela Prieto Juan Carlos Bada Manuel León‐Camacho Enrique Graciani Constante 《European Journal of Lipid Science and Technology》2008,110(2):101-110
A pilot plant‐scale continuous deodorization installation was developed to simultaneously test several technological changes in the classical deodorization process: use of nitrogen as stripping gas, heating of the gas above the liquid oil, and use of shell‐and‐tube condensers for the recovery of distillates. Deacidification trials were first carried out on mixtures of commercial refined sunflower oil and high‐oleic distillates, and subsequently on bleached olive and sunflower oils. The performance of usual working conditions was analyzed: nitrogen mass flow rate, oil temperature and oil mass flow rate. Marked differences were not observed in the results of the final acidity, compositions of free fatty acids and sterols in the deacidified oil. However, the use of shell‐and‐tube condensers makes it possible to recover liquid distillates in better conditions than in the classical process for their further concentration, while at the same time reducing process pollution. 相似文献