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61.
In response to an interpretation made by Moore and Akgerman of data taken from a recent publication, previously unexplainable phenomena are accounted for, based on new experimental results. These relate to a thermodynamic equilibrium reaction involving saturation of aromatic hydrocarbons in synthetic crude middle distillates. 相似文献
62.
Developed and evaluated several strategies for detection of randomly answered protocols for the 16 pf using 250 undergraduates. Cattell's sabotage index predicted poorly, indeed in the wrong direction, between normal and randomly answered sheets (t = 2.10, p = .05). Random and carelessness indexes were derived and predicted very well, providing ts of 15.02 and 12.67 (significant at well beyond the .001 level), respectively, between random and normal sheets. Both indexes, while correctly selecting 86 and 88% of the random answer sheets, respectively, incorrectly picked out only about 6% of the normal group. Since the design of the study included a form of cross-validation, it is suggested that these indexes might be of great practical use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Hypothesized that a warmer introduction to the MMPI would reduce defensiveness as measured by the K and F-K scores and permit the revelation of more psychiatric symptoms. Over a 7-mo period the MMPI with either a warm or cold introduction was administered to a total of 61 mothers and 47 fathers of children being evaluated in a child psychiatric clinic. The K scores were significantly higher and the F-K scores significantly lower for the cold-form group. Mothers who received the warm form scored higher on the F scale, while fathers did not differ across forms. It is concluded that, while an increase in honesty resulted from the manipulation of the forms, there was little evidence to indicate that there was also an increase in the acknowledgment of psychiatric problems. It is suggested that high K and low F-K scores, rather than indicating the covering up of symptoms, are an assertion of psychological health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Vision is a significant factor in postural stability; this study is the first to report on the effect of OSHA regulated personal protective eyewear on physiological factors associated with postural stability. Twenty college students between the ages of 19 and 25 were randomly tested in each of three eyewear conditions (control, new, and artificially aged) using a NeuroCom Balance Master System and the mCTSIB protocol. Subjects were pre-tested with no eyewear (control) on each day followed by a 5-min assembly task with random eyewear assignment. Subjects were then post-tested following the same protocol while wearing the eyewear. Data were evaluated using a two (pre/post) x three (eyewear) repeated measures analysis of variance (ANOVA). There was a significant main effect for both the eyes open/firm flat surface, and eyes open/foam flat surface conditions (p 相似文献
65.
Davidson W McGibbon GA White PW Yoakim C Hopkins JL Guse I Hambly DM Frego L Ogilvie WW Lavallée P Archambault J 《Analytical chemistry》2004,76(7):2095-2102
An indandione-containing class of inhibitors abrogates DNA replication of human papillomavirus (HPV) types 6 and 11 by binding reversibly to the transactivation domain (TAD) of the viral E2 protein and inhibiting its interaction with the viral E1 helicase. To locate the binding site of this class of protein-protein interaction inhibitors, a benzophenone derivative was used to generate an irreversibly labeled E2-TAD polypeptide. The single site of covalent modification of the E2-TAD was identified by proteolytic digestions using trypsin, LysC, and V8 proteases and characterization of the resulting peptides by LC-MS procedures. Through this methodology, the benzophenone attachment point was located at the terminal methyl of residue Met101. Evidence further pinpointed the site of photoaffinity attachment to the terminal carbon atom, which is significant in providing a definitive example of the ability to locate photoinduced cross-linking to a polypeptide with atomic resolution using solely mass spectrometric detection. The location of the inhibitor binding site vis-à-vis the Glu39 and Glu100 residues sensitive to mutation for HPV 11 E2-TAD is discussed in relation to the crystal structure of the E2-TAD from the related HPV type 16. 相似文献
66.
We outline an Eulerian framework for computing the thickness of tissues between two simply connected boundaries that does not require landmark points or parameterizations of either boundary. Thickness is defined as the length of correspondence trajectories, which run from one tissue boundary to the other, and which follow a smooth vector field constructed in the region between the boundaries. A pair of partial differential equations (PDEs) that are guided by this vector field are then solved over this region, and the sum of their solutions yields the thickness of the tissue region. Unlike other approaches, this approach does not require explicit construction of any correspondence trajectories. An efficient, stable, and computationally fast solution to these PDEs is found by careful selection of finite differences according to an upwinding condition. The behavior and performance of our method is demonstrated on two simulations and two magnetic resonance imaging data sets in two and three dimensions. These experiments reveal very good performance and show strong potential for application in tissue thickness visualization and quantification. 相似文献
67.
Fibre-optic components fabricated on the same substrate as integrated circuits are important for future high-speed communications. One industry response has been the costly push to develop indium phosphide (InP) electronics. However, for fabrication simplicity, reliability and cost, gallium arsenide (GaAs) remains the established technology for integrated optoelectronics. Unfortunately, the GaAs bandgap wavelength (0.85 microm) is far too short for fibre optics at 1.3-1.5 microm. This has led to work on materials that have a large lattice mismatch on GaAs. Here we demonstrate the first light-emitting diode (LED) that emits at 1.5 microm fibre-optic wavelengths in GaAs using optical transitions from arsenic antisite (As(Ga)) deep levels. This is an enabling technology for fibre-optic components that are lattice-matched to GaAs integrated circuits. We present experimental results showing significant internal optical power (24 mW) and speed (in terahertz) from GaAs optical emitters using deep-level transitions. Finally, we present theory showing the ultimate limit to the efficiency-bandwidth product of semiconductor deep-level optical emitters. 相似文献
68.
Mandeep M. Sahani Tarek M. Daoud Ramin Sam Jerry Andrews Yuk Lun Cheng Carl M. Kjellstrand Todd S. Ing 《Hemodialysis international. International Symposium on Home Hemodialysis》2001,5(1):92-96
An aggressive dialysis in a grossly azotemic patient, especially one with severe metabolic acidosis, can lead to dialysis disequilibrium syndrome (DDS). Mild forms present as nausea, vomiting, restlessness, and headache. Severe manifestations include seizures, obtundation, coma, and even death. This clinical picture is caused by cerebral edema induced by one or more of the following mechanisms:
- 相似文献
69.
Roberto Passerone Jerry R. Burch Alberto L. Sangiovanni-Vincentelli 《Formal Methods in System Design》2007,31(1):1-33
Embedded systems are electronic devices that function in the context of a real environment, by sensing and reacting to a set
of stimuli. Because of their close interaction with the environment, and to simplify their design, different parts of an embedded
system are best described using different notations and different techniques. In this case, we say that the system is heterogeneous. We informally refer to the notation and the rules that are used to specify and verify the elements of heterogeneous systems
and their collective behavior as a model of computation. In this paper, we consider different classes of relationships between models of computation and discuss their preservation
properties with respect to the model's refinement relation and composition operator. In particular, we focus on abstraction
and refinement relationships in the form of abstract interpretations and introduce the notion of conservative approximation. We show that, unlike abstract interpretations, conservative approximations preserve refinement verification results from
an abstract to a concrete model while avoiding false positives. We also characterize the relationship between abstract interpretations
and conservative approximations, and derive necessary and sufficient conditions to obtain a conservative approximation from
a pair of abstract interpretations. In addition, we use the inverse of a conservative approximation to identify components
that can be used indifferently in several models, thus enabling reuse across models of computation. The concepts described
in this paper are illustrated with examples from continuous time and discrete time models of computation. 相似文献
70.
Advances in type-2 fuzzy sets and systems 总被引:3,自引:0,他引:3
Jerry M. Mendel 《Information Sciences》2007,177(1):84-110