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91.
Geoffrey I. Webb Janice R. Boughton Fei Zheng Kai Ming Ting Houssam Salem 《Machine Learning》2012,86(2):233-272
Averaged n-Dependence Estimators (AnDE) is an approach to probabilistic classification learning that learns by extrapolation from marginal to full-multivariate
probability distributions. It utilizes a single parameter that transforms the approach between a low-variance high-bias learner
(Naive Bayes) and a high-variance low-bias learner with Bayes optimal asymptotic error. It extends the underlying strategy
of Averaged One-Dependence Estimators (AODE), which relaxes the Naive Bayes independence assumption while retaining many of
Naive Bayes’ desirable computational and theoretical properties. AnDE further relaxes the independence assumption by generalizing AODE to higher-levels of dependence. Extensive experimental
evaluation shows that the bias-variance trade-off for Averaged 2-Dependence Estimators results in strong predictive accuracy
over a wide range of data sets. It has training time linear with respect to the number of examples, learns in a single pass
through the training data, supports incremental learning, handles directly missing values, and is robust in the face of noise.
Beyond the practical utility of its lower-dimensional variants, AnDE is of interest in that it demonstrates that it is possible to create low-bias high-variance generative learners and suggests
strategies for developing even more powerful classifiers. 相似文献
92.
Defect‐Rich Ultrathin ZnAl‐Layered Double Hydroxide Nanosheets for Efficient Photoreduction of CO2 to CO with Water 下载免费PDF全文
93.
94.
Geoffrey Lawrence Arun V Baskar Mohammed H El-Newehy Wang Soo Cha Salem S Al-Deyab Ajayan Vinu 《Science and Technology of Advanced Materials》2015,16(2)
Three-dimensional cage-like mesoporous FDU-12 materials with large tuneable pore sizes ranging from 9.9 to 15.6 nm were prepared by varying the synthesis temperature from 100 to 200 °C for the aging time of just 2 h using a tri-block copolymer F-127(EO106PO70EO106) as the surfactant and 1,3,5-trimethyl benzene as the swelling agent in an acidic condition. The mesoporous structure and textural features of FDU-12-HX (where H denotes the hydrothermal method and X denotes the synthesis temperature) samples were elucidated and probed using x-ray diffraction, N2 adsorption, 29Si magic angle spinning nuclear magnetic resonance, scanning electron microscopy and transmission electron microscopy. It has been demonstrated that the aging time can be significantly reduced from 72 to 2 h without affecting the structural order of the FDU-12 materials with a simple adjustment of the synthesis temperature from 100 to 200 °C. Among the materials prepared, the samples prepared at 200 °C had the highest pore volume and the largest pore diameter. Lysozyme adsorption experiments were conducted over FDU-12 samples prepared at different temperatures in order to understand their biomolecule adsorption capacity, where the FDU-12-HX samples displayed high adsorption performance of 29 μmol g−1 in spite of shortening the actual synthesis time from 72 to 2 h. Further, the influence of surface area, pore volume and pore diameter on the adsorption capacity of FDU-12-HX samples has been investigated and results are discussed in correlation with the textural parameters of the FDU-12-HX and other mesoporous adsorbents including SBA-15, MCM-41, KIT-5, KIT-6 and CMK-3. 相似文献
95.
96.
It is widely accepted that understanding the kinetics of steelmaking is a complex task, and reliable and validated kinetics models are required for developing successful steelmaking process models. Therefore, as an initial attempt, this paper analyses the applicability of first order kinetics to explain the steelmaking reaction kinetics using the published data in the IMproving Phosphorus Refining research report. The process data for 20 heats in a 6?tonne pilot plant were analysed for the removal of carbon, silicon, manganese and phosphorus using first order kinetics with static and dynamic equilibrium conditions. It was observed that the removal behaviour of silicon closely followed a first order kinetics relationship, while that of carbon only approximately followed a first order kinetics relationship. The removal of manganese did not show a good degree of fit with first order kinetics using static equilibrium condition, but a clear improvement was observed when calculated using dynamic equilibrium condition. In contrast, the kinetics of phosphorus oxidation did not follow any first order relationship. 相似文献
97.
Nuclear reactors produce heat and thus can couple to heat storage systems to provide dispacthable electricity while the reactor operates at full power. Six classes of heat storage technologies couple to light-water reactors with steam cycles. Firebrick Resistance-Heated Energy Storage (FIRES) converts low-price electricity into high-temperature stored heat for industry or power. FIRES and brick recuperators coupled to nuclear brayton power cycles may enable high-temperature reactors to buy electricity when prices are low and sell electricity at higher price. 相似文献
98.
James F. Hoebel Gordon H. Damant Steven M. Spivak Geoffrey N. Berlin 《Fire Technology》2010,46(3):629-649
Between 1997 and 2006, more than 4,300 serious burn injuries per year in the United States were associated with clothing.
Ages 5–14 had the highest average annual burn injury rate, and ages 25–64 had the lowest rate. There were 120 deaths per year
in the United States associated with clothing burns between 1999 and 2004. The death rate for those over 65 was six times
the national average. The General Wearing Apparel Standard has regulated the flammability of clothing worn in the United States
since 1953. Nearly all of the clothing-related injuries and deaths have occurred in fires involving apparel that complied
with this Standard. Despite the size of this problem, there is no organized national activity under way to begin to address
these casualties. Experience with the Children’s Sleepwear Flammability Standards, issued in the 1970s, suggests that safer
garments can be manufactured that would prevent many clothing burn injuries and deaths. A more stringent up-to-date flammability
standard, production of safer garments, use of warning labels, and educated consumers are needed. 相似文献
99.
Paris Grant-Preece Celia Barril Leigh M. Schmidtke Geoffrey R. Scollary Andrew C. Clark 《Critical reviews in food science and nutrition》2017,57(4):743-754
Bottled white wine may be exposed to UV-visible light for considerable periods of time before it is consumed. Light exposure may induce an off-flavor known as “sunlight” flavor, bleach the color of the wine, and/or increase browning and deplete sulfur dioxide. The changes that occur in bottled white wine exposed to light depend on the wine composition, the irradiation conditions, and the light exposure time. The light-induced changes in the aroma, volatile composition, color, and concentrations of oxygen and sulfur dioxide in bottled white wine are reviewed. In addition, the photochemical reactions thought to have a role in these changes are described. These include the riboflavin-sensitized oxidation of methionine, resulting in the formation of methanethiol and dimethyl disulfide, and the photodegradation of iron(III) tartrate, which gives rise to glyoxylic acid, an aldehyde known to react with flavan-3-ols to form yellow xanthylium cation pigments. 相似文献
100.
Geoffrey A. Ozin 《Advanced materials (Deerfield Beach, Fla.)》2015,27(11):1957-1963
While the chemical energy in fossil fuels has enabled the rapid rise of modern civilization, their utilization and accompanying anthropogenic CO2 emissions is occurring at a rate that is outpacing nature's carbon cycle. Its effect is now considered to be irreversible and this could lead to the demise of human society. This is a complex issue without a single solution, yet from the burgeoning global research activity and development in the field of CO2 capture and utilization, there is light at the end of the tunnel. In this article a couple of recent advances are illuminated. Attention is focused on the discovery of gas‐phase, light‐assisted heterogeneous catalytic materials and processes for CO2 photoreduction that operate at sufficiently high rates and conversion efficiencies, and under mild conditions, to open a new pathway for an energy transition from today's “fossil fuel economy” to a new and sustainable “CO2 economy”. Whichever of the competing CO2 capture and utilization approaches proves to be the best way forward for the development of a future CO2‐based solar fuels economy, hopefully this can occur in a period short enough to circumvent the predicted adverse consequences of greenhouse gas climate change. 相似文献