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951.
A matching ${E_\mathcal{M}}$ of graph G = (V, E) is a subset of the edges E, such that no vertex in V is incident to more than one edge in ${E_\mathcal{M}}$ . The matching ${E_\mathcal{M}}$ is maximum if there is no matching in G with size strictly larger than the size of ${E_\mathcal{M}}$ . In this paper, we present a distributed stabilizing algorithm for finding maximum matching in bipartite graphs based on the stabilizing PIF algorithm of Cournier et al. (Proceedings of 21st IEEE international conference on distributed computing systems, 91–98, 2001). Since our algorithm is stabilizing, it does not require initialization and withstands transient faults. The complexity of the proposed algorithm is O(d × n) rounds, where d is the diameter of the communication network and n is the number of nodes in the network. The space complexity is O(log Δ + log d), where Δ is the largest degree of all the nodes in the communication network. In addition, an optimal version of the proposed algorithm finding maximum matching in linear time is also presented. 相似文献
952.
Mehmet Ertaş 《Journal of Superconductivity and Novel Magnetism》2017,30(7):1839-1847
The kinetic spin-3/2 Ising system in the presence of crystal and external oscillating magnetic fields on the triangular lattice (TL) is examined within the mean-field approximation and the Glauber-type stochastic dynamics, namely dynamic mean-field approximation (DMFA). First, the dynamic equations describing the behavior of the system are derived for the TL. Then, the dynamic equations are solved numerically to obtain the dynamic hysteresis curves of the kinetic spin-3/2 Ising ferromagnetic system, which strongly depend on the Hamiltonian parameters. Moreover, the dynamic behaviors of the coercivity and remanent magnetizations are studied depending on the temperature, crystal field and frequency of the oscillating external magnetic field. Finally, the results are compared with some experimental and theoretical studies and a qualitatively good overall agreement is observed 相似文献
953.
Software development with imperfect information 总被引:1,自引:0,他引:1
Joost Noppen Pim van den Broek Mehmet Akşit 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(1):3-28
Delivering software systems that fulfill all requirements of the stakeholders is very difficult, if not at all impossible.
We consider the problem of coping with imperfect information, like interpreting incomplete requirement specifications or vagueness
in decisions, one of the main reasons that makes software design difficult. We define a method for tracing design decisions
under imperfect information. To model and compare requirements with estimations, we present fuzzy and stochastic techniques.
This approach offers adequate decision support that can deal with imperfect information during software design. The approach
is illustrated by a real-world example, based on a storm surge barrier system. 相似文献
954.
Magnetic poly(2‐hydroxyethylmethacrylate) (mPHEMA) beads are modified by iminodiacetic acid (IDA) to implify the reactive groups and subsequent binding of Cu2+ ions to form metal chelate. mPHEMA beads, in the size range of 80–120 μm, were produced by a modified suspension polymerization technique. mPHEMA beads were characterized by swelling tests, electron spin resonance (ESR), FTIR, and scanning electron microscopy (SEM). Important results obtained in this study are as follows. The swelling ratio of mPHEMA beads was 34%. The presence of magnetite particles in the polymeric structure was confirmed by ESR. FTIR data confirmed that the magnetic polymer beads were modified with functional groups IDA. The mPHEMA beads have a spherical shape and porous structure. The effect of pH and concentration of human serum albumin (HSA), on the adsorption of HSA to the metal‐chelated magnetic beads, were examined in a batch reactor. Most importantly, the magnetic beads had little nonspecific adsorption for HSA (0.5 mg/g) before introducing IDA groups. Cu2+ chelation increased the HSA adsorption up to 28.4 mg/g. Adsorption behavior can be described at least approximately with the Langmuir equation. Regeneration of the metal‐chelated magnetic beads was easily performed with 1.0M NaSCN, pH 8.0, followed by washing with distilled water and reloading with Cu2+. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2501–2510, 2004 相似文献
955.
In this paper we investigate of energetic and exergetic efficiencies of ground-coupled heat pump (GCHP) system as a function of depth trenches for heating season. The horizontal ground heat exchangers (HGHEs) were used and it were buried with in 1 m (HGHE1) and 2 m (HGHE2) depth trenches. The energy efficiency of GCHP systems are obtained to 2.5 and 2.8, respectively, while the exergetic efficiencies of the overall system are found to be 53.1% and 56.3%, respectively, for HGHE1 and HGHE2. The irreversibility of HGHE2 is less than of the HGHE1 as about 2.0%. The results show that the energetic and exergetic efficiencies of the system increase when increasing the heat source (ground) temperature for heating season. And the end of this study, we deal with the effects of varying reference environment temperature on the exergy efficiencies of HGHE1 and HGHE2. The results show that increasing reference environment temperature decreases the exergy efficiency in both HGHE1 and HGHE2. 相似文献
956.
The study was aimed at determining the effect of chemical pretreatment on copper(II) biosorption by Marrubium globosum subsp. globosum leaves. The uptake capacity of the biomass was increased by chemical pretreatment when compared with the raw biomass. The results of biosorption experiments, carried out at the conditions of 50 mg l(-1) initial metal concentration and pH 5.5, showed that pretreating the biomass with alkali solutions (laundry detergent, sodium hydroxide and sodium bicarbonate, 0.5 M) improved the biosorption capacity of biomass (45.90, 45.78 and 43.91%, respectively) compared with raw biomass. Pretreatment with sulfuric and nitric acid solutions, 0.5 M, increased the biosorption capacity of biomass by 11.82 and 10.18%, respectively, while there was no considerable change in the biosorption capacity of biomass (0.35%) after pretreatment with formic acid solution, 0.5 M. Furthermore, sodium chloride and calcium chloride, 0.5 M, pretreatments resulted in the improvement in biosorption capacity of biomass (31.38 and 26.69%, respectively). FT-IR analysis revealed that hydroxyl and carboxyl functional groups were mainly responsible for copper(II) biosorption. 相似文献
957.
This paper presents an investigation regarding the ballistic performance of protection panels of different fabric ply numbers used in body armours. Twaron CT 710 type fabric layers of differing numbers are joined by using three stitch types to form the panels and then the panels are subjected to ballistic tests according to NIJ standards. Ballistic performance of the panels is determined by measuring trauma depth and trauma diameter. The energy absorbed by the fabric layers and the energy transmitted to the back of the fabric layers are determined from the trauma depth and trauma diameter values using a different approach. It is shown that the fabric ply number and stitching type have significant effects on ballistic properties and the effect of conditioning is limited. 相似文献
958.
Mehmet Savsar 《The International Journal of Advanced Manufacturing Technology》2008,37(7-8):760-769
This paper presents a closed form equation for calculating production rate of a flexible manufacturing module (FMM) which
operates under stochastic conditions, including random machining times, random part loading and unloading times, and random
pallet transfer times. Random operational conditions may arise due to the randomness in the variety of parts introduced into
the system. The FMM consists of two machines, one pallet handling system, and a loading/unloading robot. The model and the
resulting closed form equations allow the FMM designers and operation engineers select the most appropriate parameters for
the maximum production output rate. 相似文献
959.
The colour values of knitted cotton fabrics made from single and plied ring and compact yarns were investigated before and after dyeing. The fabric samples were knitted under the same constructional properties and then dyed with direct and reactive dyes. It was found that fabrics with ring yarns had high lightness and low chroma and colour strength values compared with fabrics with compact yarns. Also colour strength and colour difference values of dyed fabrics were assessed after increasing abrasion cycles (2500, 5000, 7500 and 10 000). The main changes in colour strength values were observed at 2500 abrasion cycles. The effect of abrasion on colour difference values of fabrics having ring yarns was more obvious than fabrics having compact yarns. 相似文献
960.
Mehmet A. Oturan Elodie Guivarch Nihal Oturan Ignasi Sirs 《Applied catalysis. B, Environmental》2008,82(3-4):244-254
A very detailed scheme for the Fe3+-catalyzed electro-Fenton mineralization of malachite green as a model triarylmethane dye is presented. Bulk electrolyses of 250-mL aqueous solutions of 0.5 mM malachite green with 0.2 mM Fe3+ as catalyst have been carried out at room temperature and pH 3.0 under constant current in an undivided cell equipped with a graphite-felt cathode and a Pt anode to assess the performance of the electro-Fenton system. In situ electrogeneration of Fe2+ and H2O2 from quick cathodic reduction of Fe3+ and dissolved O2 (from bubbled compressed air), respectively, allows the formation of the very oxidizing species hydroxyl radical (OH) in the medium from Fenton's reaction. A pseudo-first-order decay kinetics with an apparent rate constant of k1,MG = 0.244 min−1 was obtained for total destruction of malachite green by action of OH at 200 mA, requiring 22 min for total decoloration of the solution. In the same experimental conditions, overall mineralization was reached at 540 min. Up to 15 aromatic and short-chain carboxylic acid intermediates were identified along the treatment. The evolution of current efficiency was calculated from the chemical oxygen demand (COD) removal. Based on the time course of most of the by-products and the identification of inorganic ions released, some plausible mineralization pathways are proposed and thoroughly discussed. It has been found that the electro-Fenton degradation of malachite green proceeds via parallel pathways, all of them involving primary splitting of the triaryl structure initiated by attack of OH on the central carbon, thus yielding two different N-dimethylated benzophenones. Successive cleavage of the aromatic intermediates generates oxalic acid as the ultimate short-chain carboxylic acid, whereas N-demethylation of some of them produces formic acid as well. Oxalic acid and its Fe2+ complexes, as well as formic acid, can be slowly but totally mineralized by OH. 相似文献