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21.
Tomoyasu Nakamine Shugo Suzuki Kenji Nakao Makoto Okazaki 《Fullerenes, Nanotubes and Carbon Nanostructures》1995,3(4):389-398
respectively. 相似文献
22.
23.
M Takahashi F Sasaki T Namieno T Matsuhisa Y Okawa K Taguchi H Takahashi J Uchino 《Canadian Metallurgical Quarterly》1998,13(2-3):191-192
A 3-year child presented with episodic lower abdominal pain; during the eighth attack, a mass was palpable in the left upper quadrant, and a barium enema revealed a stenotic area in the transverse colon. This was resected and an uneventful postoperative course followed. Subsequently, the child has remained symptom-free. instruments are no longer in use. 相似文献
24.
S Ikeda Y Sera H Ohshiro T Izaki S Uchino M Akizuki H Goto 《Canadian Metallurgical Quarterly》1998,14(1-2):140-141
In infants and children requiring prolonged, multiple central venous (CV) catheterizations, the superior (SVC) and inferior vena cava may become thrombosed or stenotic, making CV access a difficult problem. Use of the iliac vein may be an acceptable alternative. We report a patient with thrombosis of the SVC in whom the external iliac vein was accessed through a retroperitoneal approach for placement of an implantable port. This technique is easy to perform, and there are no special materials or patient positioning required. 相似文献
25.
Applied Intelligence - A multi-agent system (MAS) is expected to be applied to various real-world problems where a single agent cannot accomplish given tasks. Due to the inherent complexity in the... 相似文献
26.
Akihiro Yamada Kuniko Kojima Koji Minami Hiroaki Sugiura Hiroshi Kida Kenji Samejima 《Journal of the Society for Information Display》2012,20(7):390-396
Stationary projectors mainly used in system applications have recently gained a wider application range, including general presentations in halls and large conference rooms and being used, for example, in digital signage and for monitoring purposes. Consequently, they are required to meet new market demands for durability, reliability, and flexibility in installation in addition to their conventional basic performance such as especially high brightness. To achieve especially high brightness, a new optical system with two lamps is proposed; the profile of the cover glass that prevents the glass from scattering is made aspherical, the profile of the beam‐combining mirror is improved with its position optimized, and the size of the incident plane of the integrator rod is made larger (1.1 times). These measures resulted in an optical system of an even higher efficiency with 7000 lm, which is the highest in its class (according to a June 2010 investigation). Also, the arrangement of two parallel lamps completely eliminated the effect of heat passing from one lamp to the other, which helped secure durability, reliability, and flexibility in installation. Furthermore, the combined use of the unique non‐telecentric optical system, adopted from the conventional single‐lamp model, helps maintain the class‐highest contrast ratio.1,2 相似文献
27.
Kenji Takizawa Yuri Bazilevs Tayfun E. Tezduyar 《Archives of Computational Methods in Engineering》2012,19(2):171-225
This is an extensive overview of the core and special space?Ctime and Arbitrary Lagrangian?CEulerian (ALE) techniques developed by the authors?? research teams for patient-specific cardiovascular fluid?Cstructure interaction (FSI) modeling. The core techniques are the ALE-based variational multiscale (ALE-VMS) method, the Deforming-Spatial-Domain/Stabilized Space?CTime formulation, and the stabilized space?Ctime FSI technique. The special techniques include methods for calculating an estimated zero-pressure arterial geometry, prestressing of the blood vessel wall, a special mapping technique for specifying the velocity profile at an inflow boundary with non-circular shape, techniques for using variable arterial wall thickness, mesh generation techniques for building layers of refined fluid mechanics mesh near the arterial walls, a recipe for pre-FSI computations that improve the convergence of the FSI computations, the Sequentially-Coupled Arterial FSI technique and its multiscale versions, techniques for the projection of fluid?Cstructure interface stresses, calculation of the wall shear stress and oscillatory shear index, arterial-surface extraction and boundary condition techniques, and a scaling technique for specifying a more realistic volumetric flow rate. With results from earlier computations, we show how these core and special FSI techniques work in patient-specific cardiovascular simulations. 相似文献
28.
Kenji Takizawa Tayfun E. Tezduyar 《Archives of Computational Methods in Engineering》2012,19(1):125-169
The computational challenges posed by fluid–structure interaction (FSI) modeling of parachutes include the lightness of the
parachute canopy compared to the air masses involved in the parachute dynamics, in the case of “ringsail” parachutes the geometric
complexities created by the construction of the canopy from “rings” and “sails” with hundreds of ring “gaps” and sail “slits”,
and in the case of parachute clusters the contact between the parachutes. The Team for Advanced Flow Simulation and Modeling
() has successfully addressed these computational challenges with the Stabilized Space–Time FSI (SSTFSI) technique, which was
developed and improved over the years by the and serves as the core numerical technology, and a number of special techniques developed in conjunction with the SSTFSI
technique. The quasi-direct and direct coupling techniques developed by the , which are applicable to cases with incompatible fluid and structure meshes at the interface, yield more robust algorithms
for FSI computations where the structure is light and therefore more sensitive to the variations in the fluid dynamics forces.
The special technique used in dealing with the geometric complexities of the rings and sails is the Homogenized Modeling of
Geometric Porosity, which was developed and improved in recent years by the . The Surface-Edge-Node Contact Tracking (SENCT) technique was introduced by the as a contact algorithm where the objective is to prevent the structural surfaces from coming closer than a minimum distance
in an FSI computation. The recently-introduced conservative version of the SENCT technique is more robust and is now an essential
technology in the parachute cluster computations carried out by the . We provide an overview of the core and special techniques developed by the , present single-parachute FSI computations carried out for design-parameter studies, and report FSI computation and dynamical
analysis of two-parachute clusters. 相似文献
29.
30.
Jesús F. Ontiveros Bing Hong Kenji Aramaki Christel Pierlot Jean-Marie Aubry Véronique Nardello-Rataj 《Journal of surfactants and detergents》2021,24(3):401-410
A series of symmetrical dialkyl methanesulfonate amphiphiles [DiC n CHSO 3 ] m M (n = 6, 7, 8) with different counter cations (Mm+ = H+, Li+, Na+, K+, Cu2+, Zn2+, Mg2+, Ca2+, Sc3+) were synthesized in five steps. Their solubility and critical micelle concentration (CMC) in water were determined highlighting a huge effect of the chain length and the nature of the cation. The hydrophilic–lipophilic balance of the surfactants were assessed with the phase inversion temperature (PIT)-slope method based on the deviation from the PIT of the reference C10E4/n-octane/0.01 M NaCl(aq) emulsion through addition of increasing amounts of the dialkyl methanesulfonates. The hydrophilicity of the surfactants was thus ranked in terms of dPIT/dxsulfonate. A “cation” scan with the [DiC 6 CHSO 3 ] m M /benzene/water systems at fw = 0.5 was finally performed confirming the hydrophilicity ranking obtained with the PIT-slope method. It revealed that the [DiC 6 CHSO 3 ] 2 Mg behaves as a “Balanced Surfactant” able to form spontaneously a three-phase microemulsion system (Winsor III) just in the presence of water and oil, in the same way as the catalytic surfactant dimethyldioctylammonium molybdate, which has the same PIT-slope. 相似文献