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41.
C García Barroso R Cela Torrijos J A Pérez-Bustamante 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1987,185(4):307-314
The different groups and/or classes among phenolic acids and aldehydes identified during the elaboration process of "fino" sherry wine have been studied. The study was carried out using different processes during the elaboration of the wine and we have attempted to establish whether the different treatments of the grape affect these groupings. The study was undertaken by means of cluster and multifactorial analysis on the data obtained by the quantitative determination of phenolic acids and aldehydes during vinification and in experiments carried out on the grape under different mechanical treatments. The analysis of phenolic acids and aldehydes was done with HPLC, using a C-18 mu-Bondapak and a stepwise composite gradient. The samples were previously extracted with ethylic ether. 相似文献
42.
Andrés García Higuera Javier de las Morenas 《Journal of Intelligent Manufacturing》2014,25(5):1197-1206
Traditional management and control models can benefit from added levels of intelligence to increase their capability to adapt to the continuous changes in global markets. After reviewing the classical definition of intelligence and its levels, this paper provides a new approach to help increase the responsiveness of management and control to changes and disturbances in the manufacturing supply chain. The ancient concept of the “Tertium Quid” has inspired a three-level community of agents (MAS-TRIO) that is proposed to improve the coordination of all actors involved. The proposed model combines Multi-Agent Systems (MAS) with Radio-Frequency Identification (RFID) to make possible a certain level of Autonomous Intelligence in the decision-taking process. This paper analyses how these levels of intelligence can be applied to management and control, and the performance of the proposed model has been tested at low and mid-levels on an experimental platform representing the facilities of a distribution centre controlled by a network of programmable logic controllers (PLCs). 相似文献
43.
The high computation requirements of global optimization algorithms, when used to solve real optimization problems, have caused the appearance of different parallelization strategies using several parallel computing architectures. In this work, the Universal Evolutionary Global Optimizer is implemented in CUDA to be run on GPU architectures (GPuEGO). This parallelization of the referred evolutionary multimodal optimization algorithm is rather different from other previous parallel implementations designed to be executed into shared or distributed memory processors. In this case, due to the special characteristics of a GPU architecture, the original data structures are not valid and it has been necessary to redefine them and all the functions that operate with them. When this approach is applied the acceleration factors achieved by GPuEGO range from \({\times }\) 6.33 to \({\times }\) 23.20 depending on the test function. 相似文献
44.
Aranzazu García M Victoria Ruiz-Méndez Concepción Romero Manuel Brenes 《Journal of the American Oil Chemists' Society》2006,83(2):159-164
By definition, virgin olive oil is consumed unrefined, although a great proportion of the olive oil produced has to be refined
to render it edible. Phenolic compounds are among the substances eliminated during the refining process; in the present work
these were characterized by HPLC, and their evolution during the different refining steps was studied. The complete refining
process removed most polyphenols from oils, but the behavior of individual compounds at each step also was observed. o-Diphenols
(hydroxytyrosol, catechol, and hydroxytyrosol acetate) and flavonoids (luteolin and apigenin) were eliminated first during
the alkaline treatment. Tyrosol and 4-ethylphenol remained in the oil until the deodorization step. A large amount of phenolic
compounds was discovered in the refining by-products such as soapstocks and deodorization distillates. In the latter streams,
the concentrations of tyrosol and 4-ethylphenol reached up to 149 and 3720 mg/kg by-product, respectively. This high level
of 4-ethylphenol and its well-known strong off-odor can interfere during further processing of the deodorization distillates,
and this must be taken into account when deciding what is to become of them. Similarly, the results of this work open the
possibility of recovering phenolic compounds from the “second centrifugation olive oils” by adding a new washing step prior
to the refining process. By including this new step, the most polar polyphenols, hydroxytyrosol and tyrosol, will diffuse
from oil to water and a concentration of up to 1400 mg/L of hydroxytyrosol may be achieved. 相似文献
45.
J. Linares-Pérez R. Caballero-Águila I. García-Garrido 《International journal of systems science》2014,45(7):1548-1562
This paper addresses the optimal least-squares linear estimation problem for a class of discrete-time stochastic systems with random parameter matrices and correlated additive noises. The system presents the following main features: (1) one-step correlated and cross-correlated random parameter matrices in the observation equation are assumed; (2) the process and measurement noises are one-step autocorrelated and two-step cross-correlated. Using an innovation approach and these correlation assumptions, a recursive algorithm with a simple computational procedure is derived for the optimal linear filter. As a significant application of the proposed results, the optimal recursive filtering problem in multi-sensor systems with missing measurements and random delays can be addressed. Numerical simulation examples are used to demonstrate the feasibility of the proposed filtering algorithm, which is also compared with other filters that have been proposed. 相似文献
46.
M. Perez-Luna J.A. Toledo-Antonio F. Hernandez-Beltrán H. Armendariz A. García Borquez 《Catalysis Letters》2002,83(3-4):201-207
The effect of alumina and nickel in sulfated ZrO2 as a catalyst for n-butane isomerization was investigated. Samples were synthesized by supporting nickel sulfated zirconia on boehmite and then calcining the material. The crystalline structure of ZrO2 was studied by X-ray powder diffraction and refined by the Rietveld method. Surface areas were determined by N2 adsorption and BET analysis, while the acid properties were studied by NH3 adsorption. The chemical reaction was carried out in a fixed-bed microreactor at 338 K under atmospheric (78 kPa) or 245 kPa total pressure. Results showed that either nickel or alumina improved the catalytic activity, but a synergic effect was observed when both components assisted. The catalytic activity was related to the relative content of tetragonal zirconia and acid site density. Alumina stabilized tetragonal zirconia increased the acid site density and presumably led to a better dispersion of nickel oxide. The catalytic activity could be related to both oxidation and acid sites produced by nickel. A bimolecular reaction mechanism helps explain the observed trends. The increase in the reaction rate would be explained by the increase in the rate of the initial step of dehydrogenation either caused by a better dispersion of nickel or higher operating pressure. 相似文献
47.
Gabino A. Carriedo Francisco J. García Alonso Alejandro Presa Soto 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(2):399-406
The chiral phosphazene copolymers {[NP(O2C12H8)]0.9[NP(O2C20H12)]0.1} (1) and {[NP(O2C12H8)]0.9[NP(O2C20H10Br2)]0.1}
n
(2) [(O2C12H8) = 2,2′-dioxy-1,1′-biphenyl; (O2C20H12) = R-2,2′-dioxy-1,1′-binaphthyl and (O2C20H10Br2) = R-6,6′-dibromo-2,2′-dioxy-1,1′-binaphthyl] were prepared by sequential substitution from [NPCl2]
n
and the corresponding dihydroxy-biphenyl or binaphthyl reagents in the presence of Cs2CO3 and K2CO3. The reaction of (2) with tBuLi in THF, followed by addition of PPh2Cl and a treatment with SiHCl3/PPh3 to eliminate any oxidized OC6H4P(O)Ph2 groups, gave the phosphine containing copolymer {[NP(O2C12H8)]0.9[NP(O2C20H10[PPh2]2)]0.1}
n
(3), that was used as a chiral ligand to support [Ru(p-cymene)Cl] complexes. The resulting catalyst was active for hydrogen
transfer from isopropyl alcohol to acetophenone but the placement of the Ru centers in the 6,6′-positions of the binaphthoxyphosphazene
units induced no enantioselectivity.
Dedicated to Professor Christopher Allen. 相似文献
48.
Henri Berthiaux Antonio Guttierrez Lavin Julio Bueno De Las Heras Marisol Muñiz Alvarez 《加拿大化工杂志》2007,85(2):158-170
Despite of its general use in industry, particle sedimentation is still a not well understood unit operation. Hydrodynamics is complex in essence, mainly because the possible volumes are depending on the operating conditions, which in turn has consequences on the stability of the equipment in unsteady state conditions. 相似文献
49.
Muñoz-Ramírez David-Octavio García-Salgado Beatriz-Paulina Ponomaryov Volodymyr Reyes-Reyes Rogelio Sadovnychiy Sergiy Cruz-Ramos Clara 《Multimedia Tools and Applications》2021,80(9):13707-13734
Multimedia Tools and Applications - The copyright protection of three-dimensional (3D) content is a matter of interest in artistic and creative works due to the rights of the holder for the... 相似文献
50.
The high shear wet granulation (HSWG) operation consists of several rate processes influenced by the raw material properties, process operational parameters, and equipment design. Their combined effect determines the granule attributes. In literature, these rate processes have been modeled using different dimensionless numbers and their correlations. Each of these dimensionless numbers represent only certain rate processes. Since many of these rate processes occur at the same time, it is necessary to simultaneously model them to account for all the important degrees of freedom. Most of the HSWG scale up approaches in literature calculate scale up conditions based on a single rate process or operating parameter of interest that can lead to sub-optimal process design. We present the development of a hybrid HSWG scale up model accounting simultaneously for all the rate processes. The approach was successfully implemented to scale up the HSWG operation across laboratory, pilot, and commercial scales. 相似文献