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131.
Autism is a serious psychological disorder with onset in early childhood. Autistic children show minimal emotional attachment, absent or abnormal speech, retarded IQ, ritualistic behaviors, aggression, and self-injury. The prognosis is very poor, and medical therapies have not proven effective. This article reports the results of behavior modification treatment for two groups of similarly constituted, young autistic children. Follow-up data from an intensive, long-term experimental treatment group (n?=?19) showed that 47% achieved normal intellectual and educational functioning, with normal-range IQ scores and successful first grade performance in public schools. Another 40% were mildly retarded and assigned to special classes for the language delayed, and only 10% were profoundly retarded and assigned to classes for the autistic/retarded. In contrast, only 2% of the control-group children (n?=?40) achieved normal educational and intellectual functioning; 45% were mildly retarded and placed in language-delayed classes, and 53% were severely retarded and placed in autistic/retarded classes. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
132.
A pressure-induced phase transformation in the lithium aluminum silicate β-eucryptite was studied with in situ Raman spectroscopy. Dense β-eucryptite composites were made via powder synthesis followed by sintering. The specimens were then subjected to diamond indentation up to applied contact stresses of about 8 GPa, while collecting Raman spectra. The appearance of a Raman peak (∼520 cm−1) at a contact stress of about 3 GPa likely corresponds to the reversible phase transformation of β-eucryptite to the orthorhombic phase ɛ-eucryptite. Loading and unloading in situ Raman indentation experiments are discussed with regards to this transformation.  相似文献   
133.
Global food security is one of the most pressing issues for humanity, and agricultural production is critical for achieving this. The existing analyses of specific threats to agricultural food production seldom bring out the contrasts associated with different levels of economic development and different climatic zones. We therefore investigated the same biophysical threats in three modelled types of countries with different economic and climatic conditions. The threats analysed were environmental degradation, climate change and diseases and pests of animals and plants. These threats were analysed with a methodology enabling the associated risks to be compared. The timeframe was 2012–2050 and the analysis was based on three underlying assumptions for 2050: the world population will have increased to 9 billion people, there will be a larger middle class in the world and climate change will be causing more extreme weather events, higher temperatures and altered precipitation. It is suggested that the risks, presented by the biophysical threats analysed, differ among the three modelled types of countries and that climate zone, public stewardship and economic strength are major determinants of these differences. These determinants are far from evenly spread among the world’s major food producers, which implies that diversification of risk monitoring and international assessment of agricultural production is critical for assuring global food security in 2050.  相似文献   
134.
High-resolution and very high resolution data conversion is dominated by the use of delta-sigma modulating converters. Oversampling and noise-shaping is employed to enable a coarsely quantized conversion with high effective resolution. The time-domain output waveform from a delta-sigma modulator is often impossible to predict analytically, therefore modulator design is largely based on high level digital simulations and rule-of-thumb estimation. However, the output waveform also largely determines the distortion caused by analog error sources in the converter. Therefore optimization of the modulator with regards to digital quantization noise might not yield an optimal design when analog errors are included. This paper extends common estimation methods to include analog error sources, with the objective of enabling more global rule-of-thumb optimization.  相似文献   
135.
Phosphine complexes of cobalt halide salts activated by diethylaluminum chloride are shown to yield highly active catalysts in the hydrovinylation of styrene, with unprecedented high selectivity to the desired product 3‐phenyl‐1‐butene (3P1B). Double‐bond isomerization, a common problem in codimerization reactions, only occurs after full conversion with these catalyst systems, even at elevated temperature. The most active catalysts are based on cobalt halide species combined with either C1‐ or C2‐bridged diphosphines, heterodonor P,N or P,O ligands, flexible bidentate phosphine ligands or monodentate phosphine ligands. Kinetic investigations show an order >1 in catalyst, which indicates either the involvement of dinuclear species in the catalytic cycle or partial catalyst decomposition via a bimolecular pathway.  相似文献   
136.
The aim was to examine how well different beef muscles from Norwegian Red bulls respond to the consumer needs. Ten carcasses were slaughtered at a commercial abbatoir, chilled at 4 °C for 48 h, and 10 muscles excised. After ageing for 9 days at 4 °C, the muscles were subjected to sensory and chemical analyses and classified according to these analyses in 4 quality groups. The results regarding the comparative quality of the muscles were similar to results from other studies on predominantly steers. M. infraspinatus showed superior tenderness, juiciness and colour properties and was the only muscle to be consistent in tenderness with 80% of the samples in the highest sensory quality class. Also M. triceps brachii and M. semimembranosus adductor were reasonably tender and consistent in tenderness. As compared with the studies on steers, the M. biceps femoris and M. vastus lateralis seemed to be less tender in bulls. Results regarding sensory colour intensity, juiciness and taste showed similar findings. The pattern of association between the muscles in this study was highly irregular as the relative muscle quality varied widely, which means that using M. longissimus dorsi as a quality indicator of all muscles in the carcass is questionable.  相似文献   
137.
The solubility of NiO in ZrO2 was studied by X-ray diffraction, TEM, and SQUID magnetometry. Lattice parameter measurements from a similar, established oxide system, NiO−10YSZ, were first used to show that SQUID magnetometry can effectively measure solubility. ZrO2 specimens with 0, 0.5, 1, 2, 3, and 5 percent by mol NiO were prepared via the Pechini method. The specimens were calcined in air at 500, 600, and 1000 °C. The paramagnetic response of the specimens measured with SQUID magnetometry revealed that up to 5 percent by mol NiO is soluble in ZrO2 for specimens calcined at 500 and 600 °C. The relatively large solubility compared with NiO−10YSZ occurs due to the very fine grain size (5–10 nm). The fine grain size is also responsible for stabilizing the tetragonal phase of ZrO2. At the 1000 °C calcination temperature, the ZrO2 is entirely monoclinic, exhibits larger grains (>45 nm), and only dissolves about 0.5 percent by mol or less NiO. The correlations between grain size, ZrO2 polytype, and NiO addition are discussed.  相似文献   
138.
To my knowledge, no other software engineering language construct as significant as use cases has been adopted so quickly and so widely among practitioners. I believe this is because use cases play a role in so many different aspects of software engineering.Although I first used the term in 1986, I had actually been working on and evolving the concept of use cases since 1967. So many people have asked me how I came up with this concept that I decided to write this article to explain the origins and evolution of use cases. Ill also summarize what they have helped us achieve so far, and then suggest a few improvements for the future.  相似文献   
139.
The structural model of dichotic listening performance predicts reduced left ear scores in people with left hemisphere language dominance and impairment of the corpus callosum. The prediction was tested in patients with multiple sclerosis and evidence on the basis of magnetic resonance imaging (MRI) of callosal thinning. The results are partly in accordance with the structural model but indicate an effect of attentional set that correlated with quantitative measures of preserved callosal connections. The pattern of ear advantage was reversed in a small group of non-right-handed people. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
140.
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