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71.
Sub‐Micron Anisotropic InP‐based III–V Semiconductor Material Deep Etching for On‐Chip Laser Photonics Devices 下载免费PDF全文
Doris Keh‐Ting Ng Chee Wei Lee Vivek Krishnamurthy Qian Wang 《Advanced Engineering Materials》2018,20(2)
72.
Materials used in soldier protective structures, such as armor, vehicles and civil infrastructures, are being improved for performance in extreme dynamic environments. Nanocrystalline metals show significant promise in the design of these structures with superior strengths attributed to the dislocation-based and grain-boundary-based processes as compared to their polycrystalline counterparts. An optimization of these materials, however, requires a fundamental understanding of damage evolution at the atomic level. Accordingly, atomistic molecular dynamics simulations are performed using an embedded-atom method (EAM) potential on three nano-crystalline aluminum atom systems, one a Voronoi-based nano-crystalline system with an average grain size of 10 nm, and the other two single crystals. These simulations are performed under the condition of uniaxial expansion at several strain rates ranging from 106s-1 to 1010s-1. Results for the effective stress are discussed with the aim of establishing the role of the strain rate and microstructure on the evolution of the plastic strain and void volume fraction and the eventual loss of stress carrying capability of the atom systems. 相似文献
73.
Mark Linton Aideen B. Mackle Vivek K. Upadhyay Alan L. Kelly Margaret F. Patterson 《Innovative Food Science and Emerging Technologies》2008,9(4):423-428
Camembert-type cheese was produced from: raw bovine milk; raw milk inoculated with 2 or 4 log CFU/ml Listeria monocytogenes; raw milk inoculated with L. monocytogenes and subsequently pressure-treated at 500 MPa for 10 min at 20 °C; or uninoculated raw milk pressure-treated under these conditions. Cheeses produced from both pressure-treated milk and untreated milk had the typical composition, appearance and aroma of Camembert. Curd and cheese made from inoculated, untreated milk contained large numbers of L. monocytogenes throughout production. An initial inoculum of 1.95 log CFU/ml in milk increased to 4.52 log CFU/g in the curd and remained at a high level during ripening, with 3.85 log CFU/g in the final cheese. Pressure treatment inactivated L. monocytogenes in the raw milk at both inoculum levels and the pathogen was not detected in any of the final cheeses produced from pressure-treated milk. Therefore high pressure may be useful to inactivate L. monocytogenes in raw milk that is to be used for the production of soft, mould-ripened cheese.
Industrial relevance
This paper demonstrates the potential of high pressure (HP) for treatment of raw milk to be used in the manufacture of soft cheeses. HP treatment significantly reduced the level of Listeria monocytogenes in the raw milk and so allowed the production of safer non-thermally processed camembert-like soft cheese. 相似文献74.
Vassilis Sakizlis Author VitaeAuthor Vitae Vivek Dua Author VitaeAuthor Vitae Efstratios N. Pistikopoulos Author Vitae 《Automatica》2004,40(2):189-201
In this paper a method is presented for deriving the explicit robust model-based optimal control law for constrained linear dynamic systems. The controller is derived off-line via parametric programming before any actual process implementation takes place. The proposed control scheme guarantees feasible operation in the presence of bounded input uncertainties by (i) explicitly incorporating in the controller design stage a set of feasibility constraints and (ii) minimizing the nominal performance, or the expectation of the performance over the uncertainty space. An extension of the method to problems involving target point tracking in the presence of persistent disturbances is also discussed. The general concept is illustrated with two examples. 相似文献
75.
Advanced high-energy plasma systems are being used to achieve the benefits of the high-velocity oxy-fuel (HVOF) system without
losing the inherent advantages of plasma for coating of gas turbine parts. MCrAlY coatings play a very important role in the
performance and reliability of gas turbine components. One of the important considerations for next generation of gas turbines,
which have more demanding conditions and need to withstand ever increasing operating temperatures, is that they should possess
very low oxygen content levels in the coating. Low oxygen content coatings are applied by the expensive low-pressure plasma
spray (LPPS)/vacuum plasma spray (VPS) technique for critical components in aero- and land-based gas turbines. This work deals
with the development of low-cost LPPS equivalent coatings (having low oxygen content) using the high-energy high-velocity
plasma spray (HEHVPS) gun and inert gas shroud. A comparison has also been made with CoNiCrAlY coatings by HVOF. 相似文献
76.
Substituted lithium ferrites having the chemical formula, Li0.35Cd0.3Fe2.35O4 and Li0.35Zn0.3Fe2.35O4, with different iron (metal) contents (2, 4, 6, 8 and 10) in wt% have been prepared by solid-state technique. Complex permeability and power loss of all samples have been measured by network analyser in the frequency range of 50–5000 kHz. Magnetic properties like saturation magnetization, coercivity, retentivity have been measured by vibrating sample magnetometer (VSM). The permeability of cadmium doped lithium ferrites exhibited higher values than zinc doped lithium ferrites. The power loss of cadmium doped lithium ferrites is lesser as compared to zinc doped lithium ferrites in the frequency range of 50–5000 kHz and at flux density of 10 mT. The behaviour of power loss with flux density has been found near about same for both series. Magnetic and power loss behaviour of the samples suggest that a small amount of Fe content can improve the properties of ferrite samples for microwave devices. 相似文献
77.
78.
Anitha Shanmugarajan Subbiah Alwarappan Subramaniam Somasundaram Rajendran Lakshmanan 《Electrochimica acta》2011,(9):3345
Electrochemical polymerization is a simple and direct technique often employed for immobilizing redox enzymes at an electrode surface. Besides these, it allows precise control over the amount, spatial distribution and orientation of the enzymes. Analytical expressions pertaining to the immobilization of enzyme by electrochemical polymerization on the electrode surface were obtained by Homotopy perturbation method (HPM). This expression further distinguishes the product of the enzyme reaction at the electrode surface from those occurring alongside the polymer employed for immobilization. These analytical results are compared with the available limiting case results and they are found to be in good agreement. 相似文献
79.
Polymer blend electrolytes comprising of poly(vinyl acetate), poly(vinylidene fluoride-co-hexafluoropropylene), LiClO4, and EC-based plasticizer combinations (EC + PC, EC + GBL, EC + DMP, EC + DBP, EC + DEC) are prepared by solvent casting technique. Ionic conductivities of the electrolytes are determined by ac impedance studies in the temperature range 303–363 K. Among the various combinations of plasticizers, EC + PC added complex exhibits maximum ionic conductivity of the order of 10−4 S cm−1 and the temperature-dependent ionic conductivity plots seem to obey the VTF relation. The structural and complex formations of the prepared samples have been confirmed by X-ray diffraction analysis. DSC technique is used to study the thermal behaviour. The surface images of the sample having maximum ionic conductivity are analyzed with the help of SEM and AFM techniques. 相似文献
80.
Vivek K. Gupta Yuyi You Veer Bala Gupta Alexander Klistorner Stuart L. Graham 《International journal of molecular sciences》2013,14(5):10122-10142
The Trk family of receptors play a wide variety of roles in physiological and disease processes in both neuronal and non-neuronal tissues. Amongst these the TrkB receptor in particular has attracted major attention due to its critical role in signalling for brain derived neurotrophic factor (BDNF), neurotrophin-3 (NT3) and neurotrophin-4 (NT4). TrkB signalling is indispensable for the survival, development and synaptic plasticity of several subtypes of neurons in the nervous system. Substantial evidence has emerged over the last decade about the involvement of aberrant TrkB signalling and its compromise in various neuropsychiatric and degenerative conditions. Unusual changes in TrkB signalling pathway have also been observed and implicated in a range of cancers. Variations in TrkB pathway have been observed in obesity and hyperphagia related disorders as well. Both BDNF and TrkB have been shown to play critical roles in the survival of retinal ganglion cells in the retina. The ability to specifically modulate TrkB signalling can be critical in various pathological scenarios associated with this pathway. In this review, we discuss the mechanisms underlying TrkB signalling, disease implications and explore plausible ameliorative or preventive approaches. 相似文献