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21.
Combining octyl(phenyl)-N,N-diisobutyl-carbamoylmethylphosphine oxide (CMPO) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) into a single process solvent for separating transuranic elements from liquid high-level waste is explored. The lanthanides and americium can be co-extracted from HNO3 into 0.2 mol/L CMPO + 1.0 mol/L HEH[EHP] in n-dodecane. The extraction is relatively insensitive to the HNO3 concentration within 0.1–5 mol/L HNO3. Americium can be selectively stripped from the CMPO/HEH[EHP] solvent into a citrate-buffered N-(2-hydroxyethyl)ethylenediaminetriacetic acid solution. Separation factors >14 can be achieved in the range pH 2.5–3.7, and the separation factors are relatively insensitive to pH—a major advantage of this solvent formulation.  相似文献   
22.
Microstructure and properties of high- T c Ba2YCu3O7- x ceramics were studied as a function of purity of raw materials and processing conditions. Technical-grade (TG) and reagent-grade (RG) raw materials were used to prepare the precursor superconducting powders, the characteristics of which were monitored by XRD, chemical analysis, and SEM. Bulk specimens were then prepared with the two master batches. XRD microphase analysis and SEM-EDS investigation did not show phase differences. J c and normal-state resistivity measurements indicated that the TG specimens had more resistive grain boundaries than did RG specimens.  相似文献   
23.
Cyclosporin-A (Cyc-A) stimulates prostanoid (PGI2) synthesis in confluent smooth muscle cells from guinea pig aorta through the release of endogenous fatty acid. Cyc-A, like other stimulatory agents for prostanoids, promotes smooth muscle cell proliferation and prostanoid synthesis in these proliferating cells. Indomethacin, a cyclooxygenase inhibitor, and exogenous arachidonic acid block the Cyc-A effect on cell proliferation.  相似文献   
24.
The main objective of the ISTS project is to develop a simulation-based training system that conducts content training without the human instructor being continuously involved. A prototype for Air Traffic Control (ATC) has been developed by isolating the domain dependent expertise from the generic system. The prototype is modularized to be easily modified, expanded, or adapted to other domains. In order to evaluate a student's performance, a simulation-based training system must be able to accurately interpret student actions. This paper will present a generic paradigm for managing and interpreting the effects of student inputs for an Intelligent Simulation Training System (ISTS).

The Control module is the manager of the ISTS. It is responsible for coordinating the communication between the simulation and the rest of the system. It is also responsible for deciding when and which modules to activate based on a set of prioritized facts. The Interpreter module determines the effects of the student input to the simulation by comparing snapshots of the simulation before and after a student input is executed. It also checks the simulation for late events.  相似文献   

25.
The authors tested effects of a 10-week group cognitive-behavioral stress management intervention among 100 women newly treated for Stage 0-II breast cancer. The intervention reduced prevalence of moderate depression (which remained relatively stable in the control condition) but did not affect other measures of emotional distress. The intervention also increased participants' reports that having breast cancer had made positive contributions to their lives, and it increased generalized optimism. Both remained significantly elevated at a 3-month follow-up of the intervention. Further analysis revealed that the intervention had its greatest impact on these 2 variables among women who were lowest in optimism, at baseline. Discussion centers on the importance of examining positive responses to traumatic events—growth, appreciation of life, shift in priorities, and positive affect—as well as negative responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
Objective: The study investigated the relative degree and timing of cortical activation associated with phonological decoding in poor readers. Method: Regional brain activity was assessed during performance of a pseudoword reading task and a less demanding, letter-sound naming task by three groups of students: children who experienced reading difficulties without attention problems (N = 50, RD) and nonreading impaired (NI) readers either with (N = 20) or without attention-deficit/hyperactivity disorder (ADHD; N = 50). Recordings were obtained with a whole-head neuromagnetometer, and activation profiles were computed through a minimum norm algorithm. Results: Children with RD showed decreased amplitude of neurophysiological activity in the superior temporal gyrus, bilaterally, and in the left supramarginal and angular gyri during late stages of decoding, compared to typical readers. These effects were restricted to the more demanding pseudoword reading task. No differences were found in degree of activity between NI and ADHD students. Regression analyses provided further support for the crucial role of left hemisphere temporoparietal cortices and the fusiform gyrus for basic reading skills. Conclusions: Results were in agreement with fMRI findings and replicate previous MEG findings with a larger sample, a higher density neuromagnetometer, an overt pseudoword reading task, and a distributed current source-modeling method. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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28.
Removing phosphate from alkaline high-level waste sludges at the Department of Energy's Hanford Site in Washington State is necessary to increase the waste loading in the borosilicate glass waste form that will be used to immobilize the highly radioactive fraction of these wastes. We are developing a process which first leaches phosphate from the high-level waste solids with aqueous sodium hydroxide, and then isolates the phosphate by precipitation with calcium oxide. Tests with actual tank waste confirmed that this process is an effective method of phosphate removal from the sludge and offers an additional option for managing the phosphorus in the Hanford tank waste solids. The presence of vibrationally active species, such as nitrate and phosphate ions, in the tank waste processing streams makes the phosphate removal process an ideal candidate for monitoring by Raman or infrared spectroscopic means. As a proof-of-principle demonstration, Raman and Fourier transform infrared (FTIR) spectra were acquired for all phases during a test of the process with actual tank waste. Quantitative determination of phosphate, nitrate, and sulfate in the liquid phases was achieved by Raman spectroscopy, demonstrating the applicability of Raman spectroscopy for the monitoring of these species in the tank waste process streams.  相似文献   
29.
Many traditional industrial products are being gradually replaced by environmental friendly alternatives. N,N‐Dimethyldecanamide and D‐limonene are solvents that fulfil the requirements to be considered green solvents and may find application in agrochemicals. This contribution deals with the study of emulsions formulated with a mixture of these solvents and an eco‐friendly emulsifier. The procedure followed for the development of these formulations was based on the application of product design principles. This led to the optimum homogenization rate and subsequently to the optimum ratio of solvents. The combination of different techniques (rheology, laser diffraction, confocal laser‐scanning microscopy, and multiple light scattering) was demonstrated to be a powerful tool to assist in the prediction of the emulsions destabilization process. Thus, we found that the optimum ratio of solvents was 75/25 (N,N‐dimethyldecanamide/D‐limonene) on account of the lack of coalescence and of a low creaming rate. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2644–2653, 2014  相似文献   
30.
Objective: The development of the ability to process spoken and written language depends upon a network of left hemisphere temporal, parietal, and frontal regions. The present study explored features of brain organization in children with spina bifida meningomyelocele (SBM) and shunted hydrocephalus, who commonly present with precocious development of word reading skills and preservation of vocabulary and grammar skills. Method: Eight children with SBM were compared with 15 IQ and reading-level matched, typically developing controls on MRI-based morphometric and Magnetic Source Imaging-derived neurophysiological profiles. Results: Children with SBM showed reduced magnetic activity in left inferior parietal regions during spoken word recognition and pseudoword reading tasks. We also noted reduced surface area/volume in inferior parietal and posterior temporal regions in SBM and increased gray matter volumes in left middle frontal regions and gyral complexity in left posterior temporal and inferior parietal regions. Conclusions: A complex pattern of changes in cortical morphology and activation may serve as evidence for structural and functional brain reorganization ensuring preservation of language and decoding abilities in children with SBM. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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