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51.
Manibarathi Vaithiyanathan Hannah C. Hymel Nora Safa Olivia M. Sanchez Jacob H. Pettigrew Cole S. Kirkpatrick Ted J. Gauthier Adam T. Melvin 《American Institute of Chemical Engineers》2021,67(1):e17087
Most cell penetrating peptides (CPPs) are unstructured and susceptible to proteolytic degradation. One alternative is to incorporate D-chirality amino acids into unstructured CPPs to allow for enhanced uptake and intracellular stability. This work investigates CPP internalization using a series of time, concentration, temperature, and energy dependent studies, resulting in a three-fold increase in uptake and 50-fold increase in stability of D-chirality peptides over L-chirality counterparts. CPP internalization occurred via a combination of direct penetration and endocytosis, with a percentage of internalized CPP expelling from cells in a time-dependent manner. Mechanistic studies identified that cells exported the intact internalized D-chirality CPPs via an exocytosis independent pathway, analogous to a direct penetration method out of the cells. These findings highlight the potential of a D-chirality CPP as bio-vector in therapeutic and biosensing applications, but also identify a new expulsion method suggesting a relationship between uptake kinetics, intracellular stability, and export kinetics. 相似文献
52.
Epoxy nanocomposites reinforced with 0–5 wt% cellulose nanocrystal (CNC) were fabricated by solution casting method. The CNCs were first dispersed in the hardener together with a co-solvent and subsequently mixed with epoxy monomer using two different protocols: bulk mixing and dropwise mixing. The dropwise mixing resulted in more homogeneously-dispersed CNCs and provided better mechanical properties, particularly higher tensile strength, tensile modulus, and work of fracture with increasing CNC content. Investigation of various CNC/hardener mixtures with different solvent content showed that the residual solvent in the composite mixture had an impact on the curing behavior of the nanocomposite epoxy and may have lowered its crosslinking density, leading to Tg depression. However, the presence of the solvent was shown to be essential for the preparation of a well-dispersed CNC phase in the hardener solution, and to form homogenous composite mixtures. Our results show that the reinforcement effect due to higher CNC concentration is more significant than the solvent effect in the hardener system and shows greater improvement in mechanical properties. The CNC component reversed the solvent plasticizing effect through its superior mechanical reinforcing effects, and the dropwise mixing process led to better dispersion compared with the bulk mixing process. 相似文献
53.
54.
Phase relations in the systems SrO-Y2O3-CuO-O2 and CaO-Y2O3-CuO-O2 at 1173 K were estab-lished by equilibrating different compositions in flowing oxygen gas at a pressure of 1.01 × 105 Pa. The quenched samples were examined by optical microscopy, X-ray diffraction (XRD), energy dis-persive analysis of X-rays
(EDAX), and electron spin resonance (ESR). In the system SrO-Y2O3-CuO-O2, except for the limited substitution of Y3+ for Sr2+ ions in the ternary oxide Sr14 Cu24O41, no new quaternary phase was found to be stable. The compositions corresponding to the solid solution Sr14-xYxCu24O41 and the compound SrCuO2+δ lie above the plane containing SrO, Y2O3, and CuO, displaced towards the oxygen apex. However, in the system CaO-Y2O3-CuO-O2 at 1173 K, all the condensed phases lie on the plane containing CaO, Y2O3, and CuO, and a new quaternary oxide YCa2Cu3O6.5 is present. The quaternary phase has a composition that lies at the center of the non-stoichiometric field of the analogous
phase YBa2Cu3O7-δ in the BaO-Y2O3-CuO-O2 system. The com-pound YCa2Cu3O6.5 has the tetragonal structure and does not become superconducting at low temperature. Surprisingly, phase relations in the
three systems CaO-Y2O3-CuO-O2, SrO-Y2O3-CuO-O2, and BaO-Y2O3-CuO-O2 are found to be quite different. 相似文献
55.
Electrical (solder resistivity and solder joint resistance) and mechanical (tensile strength and shear strength of solder
joints) parameters of the binary eutectic Sn-Ag and two alloys close to the ternary eutectic Sn-Ag-Cu composition were investigated.
The four-probe technique was used for the measurement of electrical parameters. Special equipment was constructed for the
tensile strength measurements and also for determination of the shear strengths of solder joints between a typical circuit
component and a Cu contact on a printed circuit board (PCB). It was found that electrical and mechanical properties of the
three alloys studied are comparable to data in the literature for traditional Pb-Sn solders. A joint resistance below 0.3
mΩ (Ω=ohm) and shear strength of above 20 MPa were found for an individual solder joint between a circuit component (in the
current study a “jumper” resistor) and a copper surface on a PCB. 相似文献
56.
Data-intensive problems challenge conventional computing architectures with demanding CPU, memory, and I/O requirements. Experiments with three benchmarks suggest that emerging hardware technologies can significantly boost performance of a wide range of applications by increasing compute cycles and bandwidth and reducing latency. 相似文献
57.
Cylindrical fibre actuators have been constructed by a coextrusion method using a thermoplastic polyurethane wall and a conductive grease filler. These actuators may be operated as single fibres or bundled together as actuating ropes. Key results include the validation of Carpi’s wall pressure model [F. Carpi, D.D. Rossi, Dielectric elastomer cylindrical actuators: electromechanical modelling and experimental evaluation, Mater. Sci. Eng. C-Biomimetic Supramol. Syst. 24 (2004) 555–562] and the proof-of-concept demonstration of a technique that can be used for producing inexpensive dielectric elastomer actuators on an industrial scale. 相似文献
58.
We characterize the amount of alternation between blocks of Boolean quantifiers (having both existential and universal), blocks
of real existential quantifiers, and blocks of real universal quantifiers that can be decided in parallel polynomial time
over the reals. We do so under the assumption that blocks have a uniform bound on their size, both for the case of this bound
to be polynomial and constant. On the way towards this characterization we prove a real version of Savitch’s Theorem. 相似文献
59.
We show how energy-filtered convergent-beam electron diffraction (EFCBED) patterns can be used to determine the chemical composition of buried semiconductor strained quantum wells. Our method is based on a quantitative analysis of the intensities of high-order Bragg lines in the transmitted disc of EFCBED patterns taken from plan-view samples. This analysis makes it possible to determine the displacement vector R introduced between the top and bottom parts of the matrix by the deformation of the quantum well and consequently to determine its composition. This is illustrated in the case of an In(x)Ga(1-)(x)As quantum well buried in a GaAs matrix. A detailed analysis of the effect of experimental parameters on Bragg lines intensity is performed. In particular, the importance of the choice of the diffraction vector is pointed out. The relative uncertainty on the measurement of the indium content x is found to be lower than 5% and a possible occurrence of slight compositional fluctuations in the (001) growth plane is pointed out. 相似文献
60.
Chen Shengyu Kalanat Nasrin Xie Yiqun Li Sheng Zwart Jacob A. Sadler Jeffrey M. Appling Alison P. Oliver Samantha K. Read Jordan S. Jia Xiaowei 《Knowledge and Information Systems》2023,65(8):3223-3250
Knowledge and Information Systems - Physics-based models are widely used to study dynamical systems in a variety of scientific and engineering problems. However, these models are necessarily... 相似文献