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91.
41 women with bulimia nervosa completed a brief intervention that was designed to promote symptom management. Cutoff scores for the determination of reliable and clinically significant change were calculated for several psychometric instruments that are commonly used as outcome measures in the field of eating disorders. Using these statistical procedures to assess therapeutic change, this study documents the diversity of outcomes that individuals reported following their participation in the intervention. As expected, there was a differential reporting of clinically significant change in favor of specific eating psychopathology relative to personality features and associated psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
A procedure is presented for the computation of bounds to eigenvalues of the generalized hermitian eigenvalue problem and to the standard hermitian eigenvalue problem. This procedure is applicable to iterative subspace eigenvalue methods and to both outer and inner eigenvalues. The Ritz values and their corresponding residual norms, all of which are computable quantities, are needed by the procedure. Knowledge of the exact eigenvalues is not needed by the procedure, but it must be known that the computed Ritz values are isolated from exact eigenvalues outside of the Ritz spectrum and that there are no skipped eigenvalues within the Ritz spectrum range. A multipass refinement procedure is described to compute the bounds for each Ritz value. This procedure requires O(m) effort where m is the subspace dimension for each pass. 相似文献
93.
We study communications under slowly varying channels, and consider three cases of knowledge of the channel impulse response (CIR): full knowledge, no knowledge, and partial knowledge of the CIR. By partial knowledge, we refer to knowing only either the CIR magnitudes or the CIR phases. It is known that obtaining the exact joint maximum‐likelihood estimate (MLE) of the CFO and the SFO requires a two‐dimensional search. Here, we present a new estimation method which uses the Taylor expansion of the MLE cost function, combined with the best linear unbiased estimator, to obtain a method which does not require such a search. The computational complexity of the new method is evaluated. Numerical simulations demonstrate that the new method approaches the corresponding Cramér‐Rao bound for a wide range of signal‐to‐noise ratios, and has superior performance compared to all other existing methods for approximating the solution for the joint MLE, while maintaining a low computational complexity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
94.
Mercury speciation in gypsums produced from flue gas desulfurization by temperature programmed decomposition 总被引:3,自引:0,他引:3
Temperature programmed decomposition was used to identify mercury (Hg) species in gypsum samples produced from flue gas desulfurization in two Spanish power stations (A and B). As stricter emission control/reduction policies, particularly those focusing on Hg, are being implemented, wet flue gas desulfurization (FGD) technologies used for the removal of SO2 can result in the co-removal of highly-soluble oxidized Hg. The amount of Hg retained in FGD products may increase in the future if these units are optimized for co-capture. For this reason, it is important to identify the mercury species in FGD products not only to determine the potential risk when the wastes are finally disposed of, but also to understand the behaviour of mercury during combustion and therefore to improve the technologies for mercury removal. Different mercury species were identified in the gypsum samples. In power station A, HgS were the most probable Hg species, whereas in power station B the main compound was Hg halogenated compounds. 相似文献
95.
Ron Norton 《现代显示》2010,(5):182-187
随着LED产业迅速发展,使其中埋藏着专利危机,随时威胁着企业利润,文章说明了如何利用专利转危为机,并列举了可能采取的应对策略。 相似文献
96.
Gerard E. O’Connor Jeffrey Evans Scott Black Neil Fettell Beverley Orchard Ron Theo 《Nutrient Cycling in Agroecosystems》2010,86(2):269-286
Nitrate is known to accumulate under legume crops. The effects of legume crop, inoculation, row width, sowing rate, sowing
date, and intra-cropping with wheat, on the amount and soil distribution of mineral N, residual soil water, crop biomass and
crop N were studied at Wagga Wagga in south-east Australia. After removal of most of the above-ground plant material, the
treatment effects on the biomass, N content, grain yield and grain N of wheat, established in the following season, were also
measured. In a later experiment at Wagga, the recovery of 15N applied to the mid-row of lupin crops established at three row
widths was estimated at crop maturity. At Condobolin, row width effects on the soil distribution of mineral N, biomass, N
accumulation and N fixation of crop legumes and cereals, were determined. At physiological maturity, at Wagga Wagga, very
little nitrate was left beneath cereals. Significantly more was left under legume crops, mostly below 30 cm of soil depth,
and it was distributed differently depending on crop, inoculation, and sampling location. More nitrate was left under pea
and faba than under lupin, and in response to inoculation. Mixing wheat with narrow-leaf lupin did not prevent nitrate accumulation
in soil. For most of the legumes more nitrate was left in the mid-row than in the in-row; and more nitrate was left at the
mid-row of lupin crops sown with wider rows. The additional nitrate left with wider rows increased the growth, N content,
grain yield and protein of wheat established in the following season. 15N labelled nitrate applied mid-row was used less effectively
by lupin as row width increased, in a dry season. At Condobolin, lupin established with wide rows used less soil nitrate than
with narrower rows but maintained crop N by increased N fixation. In contrast, field pea maintained N demand by increasing
nitrate uptake at intermediate row spacing. The study shows that the amount of nitrate accumulated in soil during legume cropping
is susceptible to agronomic management, particularly crop selection, row width and inoculation; and that variation in the
amount of this nitrate may carry forward to impact wheat production in the follow-on season. 相似文献
97.
An adaptive approach to control a water valve for a cooling coil, called an adaptive fuzzy logic controller (AFLC), is developed and validated in this study. The AFLC calculates the error between the supply air temperature and the supply air temperature set point for air in an air handling unit (AHU) of a heating, ventilating, and air conditioning (HVAC) system and continues to improve the fuzzy controller parameters to minimize the error. The AFLC uses genetic algorithms (GAs) to improve the fuzzy rule matrix and fuzzy membership functions for the AHU in HVAC systems. In this paper, the application of genetic algorithms for developing the AFLC is presented. After a brief background on fuzzy logic controllers and GA theory, the use of GAs is explained. Three methods of modifying the fuzzy rule matrix using the GAs are presented along with simulation and real-time experimental results. Experimental results indicate that GAs can be successfully applied to modify an AFLC rule matrix to achieve a better controller. 相似文献
98.
Ron Zevenhoven Anders Wiklund Johan Fagerlund Sanni Eloneva Ben In’t Veen Hans Geerlings Gert Van Mossel Harold Boerrigter 《Frontiers of Chemical Engineering in China》2010,4(2):110-119
The use of carbon dioxide (CO2) and calcium-containing by-products from industrial activities is receiving increasing interest as a route to valuable carbonate
materials while reducing CO2 emissions and saving natural resources. In this work, wet-chemical experimental data was assessed, which involved the carbonation
of three types of materials in aqueous solutions, namely, 1) wollastonite, a calcium silicate mineral, 2) steelmaking slag,
a by-product of steel production, and 3) paper bottom ash (PBA) from waste paper incineration. Aims were to achieve either
a high carbonation degree and/or a pure carbonate product with potential commercial value. Producing a pure precipitated calcium
carbonate (PCC) material that may find use in paper industry products puts strong requirements on purity and brightness. The
parameters investigated were particle size, CO2 pressure, temperature, solid/liquid ratio, and the use of additives that affect the solubilities of CO2 and/or calcium carbonate. Temperatures and pressures were varied up to 180°C and 4 MPa. Data obtained with the wollastinite
mineral allowed for a comparison between natural resources and the industrial by-product materials, the latter typically being
more reactive. With respect to temperature and pressure trends reported by others were largely confirmed, with temperatures
above 150°C introducing thermodynamic limitations depending on CO2 pressure. The influence of additives showed some promise, although costs may make recycling and reuse of additives a necessity
for a large-scale process. When using steelmaking slag, magnetic separation may remove some iron-containing material from
the process (although this is far from perfect), while the addition of bicarbonate supported the removal of phosphorous, aside
from improving calcium extraction. The experiments with paper bottom ash (PBA) gave new data, showing that its reactivity
resembles that of steelmaking slag, while its composition results in relatively pure carbonate product. Also, with PBA no
additives were needed to achieve this. 相似文献
99.
Herd-years of Israeli-Holsteins were stratified into three groups by two criteria: mean annualized milk yield [365 (total lactations yield/calving interval)] and mean persistency, estimated as the ratio of daily milk production at the 5th mo postpartum to daily production during the postpartum peak period. The latter was taken as an indication of the relative environmental stress on the cow. Primi- and multiparous cows were analyzed separately. Genetic parameters were estimated for annualized milk and fat production at each production and persistency group. Heritabilities increased with a rise in production for both primiparous and multiparous cows, but the effect was greater for multiparous cows. Even though persistency and production were correlated, no clear trends were evident for stratification by persistency; thus, a relationship between stress and heritability was not established. Genetic correlations among stratification groups were between .7 and .9 for persistency and between .6 and .86 for production; thus, sire x environmental interaction was greater for production than for persistency stratification. Production in a given year can be used as a criterion for selecting herds to test progeny of young sires in the following year. 相似文献
100.
A small commercially available laboratory mill was found to be suitable to dehull small batches of sorghum grain. The device used one grinding plate and an agitating dimpled plate and took about 1 min to adequately dehull the grain. At the completion of dehulling period decorticated grain was collected directly in a sample holder. Data from various cultivars, grain sizes and types of grain were reproducible. It only required 10 s to clear the device between samples. 相似文献