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111.
L. Král M. Šimandl 《International Journal of Adaptive Control and Signal Processing》2011,25(11):949-964
The article deals with a challenging problem of adaptive control design for multivariable stochastic systems with a functional uncertainty. Model of the system is based on multi‐layered perceptron neural networks where both the unknown parameters and the structure are found in real time without a necessity of any off‐line training process. The unknown parameters are estimated by a global estimation method, the Gaussian sum filter, and the structure of the neural network model is optimized by a proposed pruning method. The control law is based on a bicriterial approach to the suboptimal dual control. Two individual criteria are designed and used to introduce conflicting efforts between the estimation and control; probing and caution. A comparison of the proposed dual control and its alternative with an implementation of the pruning algorithm is shown in a numerical example. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
112.
Porous functional polymer supports are a class of material of wide interest due to the possibility of immobilising reactive species. A simplified procedure was applied for the preparation of porous polymer supports using a water‐in‐oil‐in‐water multiple emulsion. The primary emulsion was a high internal phase emulsion, having a volume fraction of water phase up to 95%. Two reactive acrylates, namely 4‐nitrophenyl acrylate and 2,4,6‐trichlorophenyl acrylate, were (separately) incorporated in the oil phase in order to obtain porous reactive polymer supports. Both acrylates were crosslinked with either divinylbenzene or ethylene glycol dimethacrylate, and beads of size ca 60 µm were obtained after the polymerisation of droplets suspended into the secondary aqueous phase. In the case of 4‐nitrophenyl acrylate and divinylbenzene as a crosslinker, particles with a star shape, the core being ca 60 µm in diameter and the arms ca 180 µm in length, were obtained. The polymers were functionalised with morpholine, tris(2‐aminoethyl)amine, piperidine or piperazine yielding supports with loadings of reactive groups of between 2.6 and 6.6 mmol g?1. The results show that multiple emulsions can be precursors for porous polymer preparation. Copyright © 2007 Society of Chemical Industry 相似文献
113.
E. Renaot Y. Hermier M. H. Valin G. Bonnier F. Adunka A. Van Der Linden M. Dobre M. Šmíd A. Bronnum T. Weckstrom E. Tegeler U. Noatsch M. Anagnostou E. Turzo-Andras S. Nemeth M. White P. Marcarino P. Steur A. Pauzha V. Augevicius M. de Groot J. Nielsen F. Helgesen W. Roszkowski E. Grudniewicz R. Kuna E. Filipe I. Lobo S. Gaita V. Chimenti J. Ivarsson S. Duris J. Ranostaj J. Bojkovski A. Steiner S. Ugur J. Gray S. Bruce R. Rusby D. Head 《International Journal of Thermophysics》2008,29(3):991-1000
The EUROMET.T-K3 comparison is the regional extension of CCT-K3. The comparison involved the six European national metrology
institutes (NMIs) previously involved in CCT-K3 (LNE-INM/CNAM, SMU, INRiM, NMi-VSL, NPL, PTB) and 18 additional European national
laboratories. The comparison was divided into five different loops, each coordinated by a co-pilot chosen from the laboratories
having participated in the CCT-K3 comparison. LNE-INM/CNAM played the role of pilot in linking the five loops. In each loop,
an artifact in the form of a standard platinum resistance thermometer (SPRT, 25 Ω) was circulated among the participating
laboratories. To have sufficient information about the possible drift of the SPRTs, the co-pilots performed a calibration
over the full temperature range at the beginning and at the end of the loop. A EUROMET reference value (ERV), taking into
account the whole comparison, was defined, and the differences (T
Lab − T
ERV) were calculated with the associated uncertainties. The method for establishing the link between the participants in CCT-K3
and in EUROMET.T-K3 is described.
Institut National de Métrologie (BNM-INM/CNAM at the time of the comparison, LNE-INM/CNAM since 1 January 2005), Paris, France. 相似文献
114.
Summary
An unusually strong molecular weight dependence of the specific refractive index increment which has been reported for solutions
of oligomers (M < 103) of p-2-methyl phenylene is attributed to the exaltation of polarizability of phenylene units. The saturation length is estimated
to be l
s≅ 6 phenylene units.
Received: 3 November 1997/Revised version: 20 April 1998/Accepted: 22 April 1998 相似文献
115.
116.
Mateja Naglič Andrej Šmidovnik Tine Koloini 《Journal of the American Oil Chemists' Society》1998,75(5):629-633
Catalytic transfer hydrogenation of corn, peanut, olive, soybean, and sunflower oils has been studied with aqueous sodium
formate solution as hydrogen donor and palladium on carbon as catalyst. Kinetic constants and selectivity have been determined
under intensive stirring in the presence of stabilizing agents. Hydrogenation reactions followed first-order kinetics with
respect to fatty acids. Besides good selectivity and short reaction time, this method offers safe and easy handling. The presence
of linolenic acid retards the migration of double bonds, which explains why soybean oil is the most appropriate for this hydrogenation
process. 相似文献
117.
118.
Prof. Dr.-Ing. Dr. Sc. J. Štěpina Dr.-Ing. P. Greilach 《Electrical Engineering (Archiv fur Elektrotechnik)》1985,68(5):329-334
Übersicht Es wird gezeigt, daß man magnetische Spannungen in einzelnen Teilen von magnetischen Kreisen als Durchflutungen von zusätzlichen fiktiven Wicklungen in das Gleichungssystem zur Berechnung der Wicklungsströme einführen kann. Diese Lösungsmethode hat den Vorteil, daß geometrisch komplizierte oder nichtlineare Teile von magnetischen Kreisen auf geometrisch einfachere bzw. lineare Modelle zurückgeführt werden, deren Berechnung bereits bekannt oder mit modernen Rechnern problemlos ist. Die sich ergebenden Transformationen haben einen klaren physikalischen Hintergrund, so daß auch die Rechenergebnisse überschaubar bleiben.
Calculation of magnetic circuits by means of fictitious ampere-turns
It is shown that magnetic potential differences in the individual parts of magnetic circuits can be considered as ampere-turns of fictitious additional windings and introduced in the equation system for winding currents in this form. This method has the advantage that geometrically complicated and nonlinear parts of magnetic circuits can be transformed into simpler and linear elements respectively, the calculation of which is already known or simply feasible with the help of modern computers. The transformations used in the approach have a solid physical significance so that also the results are intuitive.相似文献
119.
MA‐NOTMP: A Triazacyclononane Trimethylphosphinate Based Bifunctional Chelator for Gallium Radiolabelling of Biomolecules
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Sophie Poty Dr. Pauline Désogère Dr. Jakub Šimeček Dr. Claire Bernhard Dr. Victor Goncalves Dr. Christine Goze Dr. Frédéric Boschetti Dr. Johannes Notni Prof. Dr. Hans J. Wester Prof. Dr. Franck Denat 《ChemMedChem》2015,10(9):1475-1479
In the past few years, gallium‐68 has demonstrated significant potential as a radioisotope for positron emission tomography (PET), and the optimization of chelators for gallium coordination is a major goal in the development of radiopharmaceuticals. Methylaminotriazacyclononane trimethylphosphinate (MA‐NOTMP), a new C‐functionalized triazacyclononane derivative with phosphinate pendant arms, presents excellent coordination properties for 68Ga (low ligand concentration, labelling at low pH even at room temperature). A “ready‐to‐be‐grafted” bifunctional chelating agent (p‐NCS‐Bz‐MA‐NOTMP) was prepared to allow 68Ga labelling of sensitive biological vectors. Conjugation to a bombesin(7–14) derivative was performed, and preliminary in vitro experiments demonstrated the potential of MA‐NOTMP in the development of radiopharmaceuticals. This new chelator is therefore of major interest for labelling sensitive biomolecules, and further in vivo experiments will soon be performed. 相似文献
120.
J. Novák J. Šoltýs P. Eliáš S. Hasenöhrl I. Vávra 《Materials Science in Semiconductor Processing》2010,13(3):167-172
The growth of InMnAs quantum dots by low pressure MOVPE technique on patterned (1 0 0) GaAs substrates was studied. The patterning in the form of ridges with sidewalls having (2 1 1) and (3 1 1) facets was prepared by wet chemical etching via a GaAs/AlAs sacrificial etching mask structure. AFM studies showed that the dots formation and distribution were very similar for both types of facets under study. InMnAs dot density on the (3 1 1) plane is about 5–7 times lower in comparison to that on the (1 0 0) planar substrate. The dots on sidewalls are larger in comparison to average dots formatted on planar GaAs (1 0 0) substrate. The lateral dimensions of these dots are in the interval 100–180 nm. In addition, dot distribution along the sidewall (from top to bottom) is not uniform. A higher dot concentration was observed close to the intersection of (3 1 1) facets with concave bottom part of the valleys between ridges. Finally, no dots were grown on the (1 0 0) plane created by self-faceting on the top of the triangular ridges. This is probably a consequence of the high quality of the (1 0 0) facet formed by lateral overgrowth. 相似文献