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81.
Recently, due to an increasing global concern on environmental safety, titanium dioxide (TiO2) photocatalyst has been extensively researched for use as air and water pollution treatments. This study was initiative for producing an economically viable TiO2 photocatalyst material with recyclability for degradation of CHP contaminated wastewater. TiO2 P‐25, a well‐known photocatalyst, with a proper amount (15% w/w of CAC) was coated on porous silica beads (ECOLITE®) by granulation technique, using high calcium aluminate cement (CAC) as a binder (EC+CAC+15% w/w TiO2 P‐25). The experiments revealed that high concentration CHP solutions were completely degraded by EC+CAC+15% w/w TiO2 P‐25 within 5 and 7 hours. The recyclability of EC+CAC+15% w/w TiO2 P‐25 was evaluated by investigation the degradation activity of freshly prepared CHP solution under UV light irradiation using the repetitive photocatalyst beads for 6 runs. HPLC analyses indicated that the CHP degradation was completed in the 1st run and down to over 90% in the 6th run. Hence, EC+CAC+15% w/w TiO2 P‐25 showed a long durability and good recyclability for CHP degradation, resulted from the good adherence of hydration product layer of CAC for TiO2 particles as well as its large surface area that offered good adsorption for CHP.  相似文献   
82.
GaN films were grown on SiC/Si (111) substrates by hot-mesh chemical vapor deposition (CVD) using ammonia (NH3) and trimetylgallium (TMG) under low V/III source gas ratio (NH3/TMG = 80). The SiC layer was grown by a carbonization process on the Si substrates using propane (C3H8). The AlN layer was deposited as a buffer layer using NH3 and trimetylaluminum (TMA). GaN films were formed and grown by the reaction between NHx radicals, generated on a tungsten hot mesh, and the TMG molecules. The GaN films with the AlN buffer layer showed better crystallinity and stronger near-band-edge emission compared to those without the AlN layer.  相似文献   
83.
Designing introductory materials is extremely important when developing new information visualization techniques. All users, regardless of their domain knowledge, first must learn how to interpret the visually encoded information in order to infer knowledge from visualizations. Yet, despite its significance, there has been little research on how to design effective introductory materials for information visualization. This paper presents a study on the design of online guides that educate new users on how to utilize information visualizations, particularly focusing on the employment of exercise questions in the guides. We use two concepts from educational psychology, learning type (or learning style) and teaching method, to design four unique types of online guides. The effects of the guides are measured by comprehension tests of a large group of crowdsourced participants. The tests covered four visualization types (graph, scatter plot, storyline, and tree map) and a complete range of visual analytics tasks. Our statistical analyses indicate that online guides which employ active learning and the top‐down teaching method are the most effective. Our study provides quantitative insight into the use of exercise questions in online guides for information visualizations and will inspire further research on design considerations for other elements in introductory materials.  相似文献   
84.
Sato  Yuzuru  Ikegami  Takashi 《Minds and Machines》2004,14(2):133-143
This paper considers undecidability in the imitation game, the so-called Turing Test. In the Turing Test, a human, a machine, and an interrogator are the players of the game. In our model of the Turing Test, the machine and the interrogator are formalized as Turing machines, allowing us to derive several impossibility results concerning the capabilities of the interrogator. The key issue is that the validity of the Turing test is not attributed to the capability of human or machine, but rather to the capability of the interrogator. In particular, it is shown that no Turing machine can be a perfect interrogator. We also discuss meta-imitation game and imitation game with analog interfaces where both the imitator and the interrogator are mimicked by continuous dynamical systems.  相似文献   
85.
Here we report on a new and rapid immunoassay for the label-free voltammetric detection of human chorionic gonadotropin hormone (hCG) in urine. Monitoring the changes in the current signals of antibodies (Abs) before and after the binding of the antigen (Ag) provides the basis for an immunoassay that is simple, rapid, and cost-effective. Since hCG is found at highly elevated levels in pregnant female urine with the range of 30,000-200,000 mIU/mL (approximately 30-200 nM) by 8-10 weeks into pregnancy, its label-free electrochemical detection was achieved by using our method. The coverage of the electrode surface with the Ab and the incubation time with the target Ag were optimized for the detection of hCG. The limit of detection of our method was calculated to be 15 pM (n = 3, approximately 15 mIU/mL) in synthetic hCG samples and 20 pM (n = 3, approximately 20 mIU/mL) in human urine. The electrochemical results for the detection of hCG in the urine samples were in agreement with the results obtained using a reference system, enzyme-linked immunosorbent assay. Further research about the intrinsic electroactivity of Abs and their target molecules would surely provide new and sensitive screening assays, as well as extensive data regarding their interaction mechanisms.  相似文献   
86.
The effects of wastewater salinity on both nitrogen removal efficiency and N2O emission rate were investigated in a single nitrification process, a single denitrification process and an anoxic-oxic activated sludge process. In the single nitrification process, by increasing the salt concentration from 1.0 to 2.0 wt%, the N2O conversion ratio in the steady state increased by 2.2 times, from 0.22 to 0.48%. In the single denitrification process, a minimal change in the N2O conversion ratio was observed in the steady state even when the salt concentration was increased from 3.0 to 5.0 wt%. From the results of the anoxic-oxic activated sludge process, it was found that a salt concentration increase from 1.6 to 3.0 wt% significantly increases the N2O conversion ratio from 0.7 to 13%. It is suggested that an increase in salt concentration markedly influences N2O emission both directly and indirectly via the inhibition of N2O reductase activity. The indirect inhibition is due to the high concentration of dissolved oxygen which is transported from the oxic tank to the anoxic tank through the circulated liquid. Thus, the salt concentration should be maintained below 3.0% to suppress N2O emission in an anoxic-oxic activated sludge process.  相似文献   
87.
The leak-before-break(LBB) behaviour of a structural component under high fatigue stress, low-cycle fatigue conditions is an important problem in nuclear power plants, liquid nitrogen gas tankers and chemical plants. This paper is an experimental study to clarify the crack shape at penetration, crack opening behaviour after penetration and the LBB condition for plate specimens and pipe specimens. The fatigue load which realizes the LBB condition, PFLBB' is based on a net-stress criterion. It is found that PFLBB is dependent only on the initial crack length a0. Furthermore, it is shown that the crack opening displacement V at the centre of a penetrated crack can be derived using the gross stress, σG' and the front surface crack length, as' together with the back surface crack length, ab.  相似文献   
88.
Recent genetic studies show that the apolipoprotein E (ApoE) epsilon 4 allele is a risk factor for Alzheimer's disease (AD). Whether this allele is associated with other dementing diseases is the next important question. The information could provide a clue to the pathogenetic role of ApoE. In the present study, patients with Wernicke-Korsakoff syndrome (WKS) of alcoholic etiology were divided into two groups according to the severity of intellectual deficits, i.e., those of "classical" Korsakoff patients with preserved intellectual function other than amnesia and those with global intellectual deficits. Genotyping showed that the frequency of ApoE epsilon 4 allele was significantly higher in the patients with global deficits, suggesting the involvement of this allele in the intellectual decline of WKS. In contrast, distributions of other two markers, alpha 1-antichymotrypsin and presenilin-1, did not differ between the two groups. These results added further support to the notion that the consequence of acute insult to the brain is influenced by the ApoE genotype, and suggested ApoE's role in the development of a certain group of "alcoholic dementia."  相似文献   
89.
Business development is vital for any firms. However, globalization and the rapid development of technologies have made it difficult to find appropriate business partners such as suppliers and customers, and build reciprocal relationships among them, while it simultaneously offers many opportunities. In this contribution, we propose AI-based approach to find plausible candidates of business partners using firm profiles and transactional relationships among them. We employ machine learning techniques to build a prediction model of customer–supplier relationships. We applied our approach to the large amount of actual business data. The results showed that our approach successfully found potential business partners with F-values of about 84% and reciprocity among them with F-values of about 77%. Using our method, we also developed the Web-based system that helps people in actual businesses to find their new business partners. These contribute to developing one’s own business in the complicated, specialized and rapidly changing business environments of recent years.  相似文献   
90.
Okawa  Maya  Iwata  Tomoharu  Tanaka  Yusuke  Kurashima  Takeshi  Toda  Hiroyuki  Kashima  Hisashi 《Machine Learning》2022,111(8):2929-2950
Machine Learning - Massive spatio-temporal event data sets are now available that cover events such as disease outbreaks, armed conflicts and crimes. Predicting such events and revealing the...  相似文献   
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