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61.
J. A. van Kan P. G. Shao K. Ansari A. A. Bettiol T. Osipowicz F. Watt 《Microsystem Technologies》2007,13(5-6):431-434
P-beam writing (proton beam writing), a direct write 3D nano lithographic technique has been employed for the production of
X-ray masks in a single step fabrication process, with high aspect ratios and extremely smooth absorber edges. P-beam writing
employs a focused MeV proton beam scanned in a predetermined pattern over a resist (e.g. PMMA or SU-8), which is subsequently
chemically developed. P-beam writing in combination with electroplating appears ideally suited to directly write X-ray masks
with nano sized features, high aspect ratios, small lateral feature sizes, and smooth and vertical sidewalls. Sub 100 nm resist
structures with aspect ratios up 160 have been produced, as well as metallic (nickel) structures down to the 100 nm level.
Preliminary tests on p-beam written X-ray test masks show that Ni stencils can be fabricated with a thickness of 2–20 μm,
smooth side walls, feature details down to 1 μm, and aspect ratios up to 20. 相似文献
62.
Shib Sankar Sana 《International journal of systems science》2013,44(3):491-498
Up to now, many newsboy problems have been considered in the stochastic inventory literature. Some assume that stochastic demand is independent of selling price (p) and others consider the demand as a function of stochastic shock factor and deterministic sales price. This article introduces a price-dependent demand with stochastic selling price into the classical Newsboy problem. The proposed model analyses the expected average profit for a general distribution function of p and obtains an optimal order size. Finally, the model is discussed for various appropriate distribution functions of p and illustrated with numerical examples. 相似文献
63.
Casein micelles as a vehicle for iron fortification of foods 总被引:1,自引:0,他引:1
Sana Raouche Marie Dobenesque Arjen Bot Alain Lagaude Sylvie Marchesseau 《European Food Research and Technology》2009,229(6):929-935
Casein micelles were loaded with iron to create a dispersible delivery format for insoluble iron by exposing milk at chilled
temperatures to a high concentration of soluble iron (up to 20 mmol kg−1 ferrous and ferric chloride). The loading was maximised by applying a pH-cycle to the fortified milk by means of carbonation.
Upon acidification of fortified milk, no release of iron was observed, except at the highest concentration. Changes in the
buffering capacity as a function of pH confirmed the formation of colloidal iron phosphates. Overall, most properties of the
micelles did not change: hydration, protein distribution between soluble and colloidal phase remained constant, but zeta potential
decreased slightly and curd formation upon renneting became much slower. The renneting behaviour could be improved by carbonation
or storage at 30 °C for a day. Iron-fortified milk samples were stable under heating, except when fortification was achieved
by means of 20 mmol kg−1 ferric chloride. The most obvious difference of iron-fortified milk is its appearance: samples fortified with ferrous chloride
were darker than control, whereas samples fortified with ferric chloride were more red/yellow. 相似文献
64.
M. H. Ansari M. S. Ahmad Jr. M. Ahmad 《Journal of the American Oil Chemists' Society》1985,62(12):1659-1662
Methyltrans-2,3-epoxyhexadecanoate on refluxing with urea in dimethylformamide (DMF) afforded isomeric 4(5)-tridecyl-5(4)-carbomethoxy-cis-2-oxazolidone (II), 5-tridecylmethylene hydantoin (II) and 2-hydroxy-3-carbamidohexadecanoic acid (III).
Presented at the 4th Convention of the Indian Council of Chemists at Uttar Pradesh, India, December 1984. 相似文献
65.
Sufyan Ababneh Rashid Ansari Ashfaq Khokhar 《Journal of Visual Communication and Image Representation》2009,20(5):303-311
Multimedia content authentication can be achieved by deriving a fragile content-based signature from a media signal and embedding it robustly back into the signal. The perturbation due to embedding needs to be compensated with mechanisms that lead to producing the original signature. Closed form solutions for compensation are not always feasible. In this paper, we propose two iterative compensation schemes to address such scenarios. The first is based on a set-theoretic approach by using projections onto convex sets (POCS), where signature generation and signal fidelity are modeled as convex constraint sets. The other scheme uses an additive iterative approach used in the cases where the POCS approach is not applicable. Examples of successful image authentication are presented to demonstrate the effectiveness of the proposed schemes over a range of watermark-embedding robustness. A comparison with the closed-form compensation scheme, when feasible, is also presented. 相似文献
66.
67.
Hamid Ansari Ardeh Masoud Shariatpanahi Mansour Nikkhah Bahrami 《Structural and Multidisciplinary Optimization》2008,37(2):203-214
This paper presents a new approach to the shape optimization of road speed humps. The proposed approach is based on multiobjective
genetic optimization of the hump profile while taking into account the separation phenomenon, which occurs when the front
tires of the vehicle momentarily lose contact with the road surface. The optimization is carried out for speeds up to twice
the authorized speed (throughout this article, the term authorized speed refers to speed limits enforced in speed reduction [bump] areas of the roads) rather than for illegally high speeds as adopted
by many of the previous works. A 6-degree of freedom non-linear dynamic model is used to identify the speeds at which separation
occurs, and hump profiles associated with these speeds are discarded as infeasible solutions. Three independent objective
functions are selected for optimization. They include the maximum vertical acceleration experienced by the driver when crossing
the hump below the authorized speed limit (to be minimized), the same vertical acceleration at speeds above the authorized
speed (to be maximized), and the ascending ratio of the “speed—vertical acceleration” curve (to be maximized). These objective
functions are evaluated for more than 10,000 humps of two popular profile types (sinusoidal and flat top with straight ramps)
and optimum profiles for three speed limits of 20, 25, and 30km/h are determined using the multiobjective nondominated sorting
genetic algorithm II. As a result, a Pareto front of at least ten optimal points is achieved for each of the two hump profile
types. Furthermore, to incorporate the economical aspects of the real-world problem, Pareto optimal points for the two profile
types were compared based on their lateral section areas (an indication of the manufacturing cost). The comparison shows that
sinusoidal humps more often than not outdo their flat top rivals economically. 相似文献
68.
The relationship between microstructure and dissolution rate of three-component granules was investigated. Granules were prepared by fluid bed granulation from sucrose spheres as model excipient, sodium chloride as model active ingredient, and polyethylene glycol (PEG) as in situ melt binder. A novel method for controlling the distribution of active ingredient within the granule was developed, based on suspending its particles in the binder prior to granulation. Granule microstructure was varied by systematically changing the NaCl particle size and the active/excipient ratio in granules. The dissolution rate of granules in water was measured by conductometry. A minimum was found in the functional dependence of dissolution time on NaCl fraction in the granule, in line with earlier computer simulations. The primary particle size was found to influence dissolution time in a nonlinear way depending on the fraction of available particle surface immersed in the binder. The intrinsic binder dissolution can therefore be rate-controlling if primary particles of the active ingredient are totally coated by binder. This was confirmed by comparing the dissolution times of granules prepared with PEGs of different molecular weight. 相似文献
69.
A novel probabilistic production costing algorithm called the OPCOST method is presented which recognizes the stochastic nature of the duty cycle of a unit and models the generation system with explicit consideration of such operating characteristics as the system generation reserve policy, unit start-up delay, unit start-up failure, unit commitment policy, and unit outage postponability. The OPCOST method has been used to compute production costs for EPRI synthetic generating system E, reduced version. The studies of the sample system have been carried out for two production costing methods, the OPCOST method and a traditional method. A comparison of the results obtained using the traditional method and the OPCOST method shows significant differences in the energies produced by the various categories of units 相似文献
70.
A Ansari 《Canadian Metallurgical Quarterly》1986,33(1):321-329