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991.
In this paper, open-loop resonators loaded by shunt open stubs are proposed to design compact dual-band bandpass filters with improved out-of-band rejection characteristics. The second passband of the dual-band filter is obtained by tuning higher resonant modes of the open-loop resonator by the stub length and position. A tapped-line input/output feed structure is used for external coupling. Required external coupling is obtained by adjusting the tapping position and dimension of the stub-loaded resonator. A lossless transmission line model is used to determine the resonance properties of the resonator and the external quality factor. Theoretical predictions are verified by the experimental results of three dual-band filters. 相似文献
992.
Optimisation of ingredients for a low‐fat,Chhana‐based dairy spread using response surface methodology
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Kumar Amitraj Kaushik Khamrui Hosapalya Chikkathimmappa Devaraja Surajit Mandal 《International Journal of Dairy Technology》2016,69(3):393-400
The effect of ingredients, viz. chhana, skimmed milk powder (SMP), maltodextrin and whey powder, on sensory and texture responses of a low‐fat chhana‐based spreads was studied and its formulation was optimised using response surface methodology. In linear and quadratic terms, chhana and SMP significantly influenced all the responses. The interaction term between maltodextrin and chhana was the most effective in influencing texture parameters. Optimisation suggested 55.6% chhana, 6.2% SMP, 4% maltodextrin, 2% whey powder, 1.5% edible salt, 1.5% enzyme‐modified cheese, 0.5% sodium tripolyphosphate, 0.5% trisodium citrate, 0.3% glycerol monostearate and 28% water with desirability of 0.889, as the best levels of these ingredients in a formulation that also contained 1.5% edible salt, 1.5% enzyme‐modi ed cheese, 0.5% sodium tripolyphosphate, 0.5% trisodium citrate, 0.3% glycerol monostearate and 28% water on a w/w basis. 相似文献
993.
The aim of this paper is to examine the existence and direction of the causal relationship between energy consumption and output growth in the Indian cement industry for the period 1979–80 to 2004–05. The most recently developed panel unit root, a heterogeneous panel cointegration and panel-based error correction model, is applied within a multivariate framework. The empirical results confirm a positive, long-run cointegrated relationship between output and energy consumption when heterogeneous state effects are taken into account. We also found a long-run, bi-directional relationship between energy consumption and output growth in the Indian cement industry for the study period, implying that an increase in energy consumption directly affects the growth of this sector and that growth stimulates further energy consumption. These empirical findings imply that energy consumption and output are jointly determined and affect each other. The empirical evidence also suggests the implementation of energy conservation policies oriented toward improving energy-use efficiency to avoid any negative impacts of the conservation policies on the growth of this industry. 相似文献
994.
Sambasivarao Kotha Kalyaneswar Mandal KapildevK. Arora V.R. Pedireddi 《Advanced Synthesis \u0026amp; Catalysis》2005,347(9):1215-1218
The synthesis of a [1.1.6] metapara cyclophane derivative, 1,5(1,4),3(1,3)‐tribenzenacycloundecaphan‐8‐ene‐6,11‐dione, has been achieved via the Suzuki–Miyaura cross‐coupling of α,α′‐dibromo‐m‐xylene with an arylboronic acid derivative followed by an allylation and ring‐closing metathesis reaction sequence. 相似文献
995.
Microstructural study of galvanized coatings formed in pure as well as commercial grade zinc baths 总被引:1,自引:0,他引:1
G. K. Mandal D. Mandal S. K. Das R. Balasubramaniam S. P. Mehrotra 《Transactions of the Indian Institute of Metals》2009,62(1):35-40
This investigation is an effort to have a better understanding of the growth kinetics and morphology of the coating formed
during the galvanizing process in pure as well as commercial grade zinc baths. The protective coating that is formed during
hot dip galvanizing, normally between 450 and 480°C, consists of a series of Fe-Zn intermetallic layers, which have been identified
as gamma (Γ), delta (δ), zeta (ξ) and an outer eta (η) layer, highly rich in zinc. There is apparently no delay in the formation
of ξ or δ phases in both pure as well as the commercial grade zinc baths. The gamma (Γ) phase is formed after an incubation
time of about 30 s at a bath temperature of 470°C in the pure zinc bath. Its formation is further delayed in the commercial
grade zinc bath. The last morphological feature is the formation of a second ξ layer at the ξ/δ interface in the pure zinc
bath. In the commercial grade zinc bath two different morphologies of ξ phase are seen starting from the lowest dipping time,
and also the overall coating is considerably thicker due to formation of several iron-zinc intermetallics which degrade its
ductility and outward appearance. Commercial grade zinc also enhances the dross formation in the bath and deteriorates the
quality of the coating. Presence of transverse cracks as well as entrapment of dross particles in the coating is attributed
to the less compact coating that is formed in the commercial grade zinc bath. 相似文献
996.
Mandal C. Chakrabarti P.P. Ghose S. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2000,8(6):747-750
We present here a technique for allocation and binding for data path synthesis (DPS) using a Genetic Algorithm (GA) approach. This GA uses an unconventional crossover mechanism relying on a force directed data path binding completion algorithm. The data path is synthesized using some supplied design parameters. A bus-based interconnection scheme, use of multi-port memories, and provision for multicycling and pipelining are the main features of this system. The method presented here has been applied to standard benchmark examples and the results obtained are promising 相似文献
997.
The role of pH in the green synthesis of silver nanoparticles (AgNPs) is investigated. For the reduction synthesis of AgNPs we use silver nitrate, glucose, sodium hydroxide and starch respectively to serve as precursor, reducing agent, accelerator and stabilizer. The effect of NaOH addition on the nature of AgNPs is systematically studied. Two reaction pathways are proposed to explain the formation of AgNPs, keeping in view the pH changes that occur on addition of different amounts of NaOH. The aqueous sol of AgNPs prepared at different pH values display different surface plasmon resonance (SPR) behavior. This is explained in terms of size and size distribution of AgNPs. 相似文献
998.
6Li produces tritium by (n, α) nuclear reaction, 6Li + 1n → 4He + 3H. Lithium titanate (Li2TiO3) enriched with 6Li, is the most promising candidate for solid test blanket module (TBM) material for fusion reactors. Various processes are reported in literature for the fabrication of Li2TiO3 pebbles for its use as TBM material. A process has been developed based on the solid state reaction of lithium-carbonate and titanium-dioxide for the synthesis of lithium titanate and pebble fabrication by extrusion, spherodization and sintering. This paper discusses the sequence of steps followed in this process and the properties obtained. Analytical grade titanium-dioxide and lithium-carbonate were taken in stoichiometric ratio and were milled to ensure thorough intimate mixing and obtain fine particles less than 45 μm before its calcination at 900 °C. Following calcination, the agglomerated product was again milled to fine particles of size less than 45 μm. Aqueous solution of ploy-vinyl-alcohol was added as binder prior to its feeding in the extruder. The extruded strips were spherodized and spherical pebbles were dried and sintered at 900 °C for different duration. Pebbles of desired density and porosity were obtained by suitable combination of sintering temperature and duration of sintering. Properties of the prepared pebbles were also characterized for sphericity, pore size distribution, grain size, crushing load strength, etc. The values were found to be conforming to the desired properties for use as solid breeder. The attractive feature of this process is almost no waste generation. 相似文献
999.
1000.
In the present investigation, Al–X?wt-% Mg2Si (X?=?0, 5, 10, 15 and 20) in situ composites are successfully synthesised by one-step gravity casting technique. Commercially pure Al, Mg and Si are used as raw materials. Microstructural evaluation and correlation of micro- and bulk hardness properties have been studied on developing composites. The composites consist of mainly three phases: matrix (α-Al), reinforcing (primary Mg2Si) and binary eutectic (Al–Mg2Si) phase. Primary Mg2Si particles are formed by pseudo-eutectic transformation during solidification and surrounded by matrix and binary eutectic phase. It is found that Mg2Si concentration has a significant impact on morphology and volume per cent of the above-mentioned phases. Primary Mg2Si particles’ size and volume per cent increase with increasing wt-% of Mg2Si. Volume per cent of individual phases and Mg2Si concentration have great impact on hardness properties of composites. Bulk hardness increases with increasing wt-% of Mg2Si concentration, but micro-hardness of primary Mg2Si particle decreases slightly. Mg2Si concentration also has significant impact on micro-hardness of individual phases. 相似文献