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51.
Clean Technologies and Environmental Policy - The decision-making in energy sector involves finding a set of energy sources and conversion devices to meet the energy demands in an optimal way....  相似文献   
52.
This study examined fluctuations in the experience of conflict between work and family and burnout in different phases of business travel as well as the relationship between work-family conflict (WFC) and burnout among 58 business travelers. Travelers completed questionnaires at 3 points in time: prior to going abroad, during the stay abroad, and after their return. An analysis of variance detected a different pattern of fluctuations in the levels of both WFC and burnout according to gender. Furthermore, while WFC at the pretrip and midtrip periods did not predict burnout in subsequent measurements, pretrip burnout did predict WFC during the trip and after the trip (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.

Feature selection (FS) methods are necessary to develop intelligent analysis tools that require data preprocessing and enhancing the performance of the machine learning algorithms. FS aims to maximize the classification accuracy by minimizing the number of selected features. This paper presents a new FS method using a modified Slime mould algorithm (SMA) based on the firefly algorithm (FA). In the developed SMAFA, FA is adopted to improve the exploration of SMA, since it has high ability to discover the feasible regions which have optima solution. This will lead to enhance the convergence by increasing the quality of the final output. SMAFA is evaluated using twenty UCI datasets and also with comprehensive comparisons to a number of the existing MH algorithms. To further assess the applicability of SMAFA, two high-dimensional datasets related to the QSAR modeling are used. Experimental results verified the promising performance of SMAFA using different performance measures.

  相似文献   
54.

Background

It has been shown that supplementation with creatine (Cr) and glycerol (Gly), when combined with glucose (Glu) necessary for the enhancement of Cr uptake by skeletal muscle, induces significant improvements in thermoregulatory and cardiovascular responses during exercise in the heat.

Purpose

To determine whether Cr/Gly-induced thermoregulatory and cardiovascular responses are maintained when the majority (~75%) of the Glu in the Cr/Gly supplement is replaced with the insulintropic agent alpha lipoic acid (Ala).

Methods

22 healthy endurance trained cyclists were randomly assigned to receive either 20?g/day (4?×?5?g/day) of Cr, 2?g .kg-1 BM per day (4?×?0.5?g .kg-1 BM per day) of Gly and 150?g/day (4?×?37.5?g/day) of Glu or 20?g/day (4?×?5?g/day) of Cr monohydrate, 2?g .kg-1 BM per day (4?×?0.5?g .kg-1 BM per day) of Gly (100?g/day (4?×?25?g/day) of Glu and 1000?mg/day (4?×?250?mg/day) of Ala for 7?days for 7?days. Exercise trials were conducted pre- and post-supplementation and involved 40?min of constant-load cycling exercise at 70% O2 max by a self-paced 16.1?km time trial at 30°C and 70% relative humidity.

Results

Median and range values of TBW increased significantly by 2.1 (1.3-3.3) L and 1.8 (0.2-4.6) L in Cr/Gly/Glu and Cr/Gly/Glu/Ala groups respectively (P?=?0.03) and of BM not significantly by 1.8 (0.2-3.0) kg and 1.2 (0.5-2.1) kg in Cr/Gly/Glu and in Cr/Gly/Glu/Ala, respectively (P?=?0.75). During constant load exercise, heart rate (HR) and core temperature (Tcore) were significantly lower post-supplementation: HR was reduced on average by 3.3?±?2.1 beats/min and by 4.8?±?3.3 beats/min (mean ± SD) and Tcore by 0.2?±?0.1 (mean ± SD) in the Cr/Gly/Glu and Cr/Gly/Glu/Ala, respectively The reduction in HR and Tcore was not significantly different between the supplementation groups.

Conclusions

In comparison to the established hyper hydrating Cr/Gly/Glu supplement, supplement containing Cr/Gly/Ala and decreased amount of Glu provides equal improvements in thermoregulatory and cardiovascular responses during exercise in the heat.  相似文献   
55.
The design of dynamic Label-Switched Paths (LSP’s) in MultiProtocol Label Switched (MPLS) networks is an NP-hard optimization problem. An LSP is a logical path between two nodes in the network. This path has a pre-reserved amount of bandwidth that defines its size. The LSP design problem consists of determining the number of these logical links and configuring the physical path and the size of each LSP. This paper presents an optimization model based on game theory. In this approach, connection requests are modeled as competitive players in a noncooperative game context. The transport network bandwidth constitutes the resource for which optimization is sought. The outcome of this optimization is a set of LSPs upon which the competing connections are routed.  相似文献   
56.
The article aims to evaluate the potential role of nuclear energy in Lithuania under various post-Kyoto climate change mitigation regimes. Seeking to achieve this target the analysis of possible energy sector development scenarios in Lithuania was performed and CO2 emission projections for these scenarios were developed. The analysis of post-Kyoto climate change mitigation architectures was performed and the requirements of these possible climate change mitigation regimes for greenhouse gas (GHG) emission reduction in Lithuania were assessed. Based on these assessments the potential role of new nuclear power in Lithuania was identified under various future climate change mitigation regimes.  相似文献   
57.
In continuation of our endeavor towards the development of potent and effective antimicrobial agents, three series of halophenyl bis-hydrazones (14a–n, 16a–d, 17a and 17b) were synthesized and evaluated for their potential antibacterial, antifungal and antimycobacterial activities. These efforts led to the identification of five molecules 14c, 14g, 16b, 17a and 17b (MIC range from 0.12 to 7.81 μg/mL) with broad antimicrobial activity against Mycobacterium tuberculosis; Aspergillus fumigates; Gram positive bacteria, Staphylococcus aureus, Streptococcus pneumonia, and Bacillis subtilis; and Gram negative bacteria, Salmonella typhimurium, Klebsiella pneumonia, and Escherichia coli. Three of the most active compounds, 16b, 17a and 17b, were also devoid of apparent cytotoxicity to lung cancer cell line A549. Amphotericin B and ciprofloxacin were used as references for antifungal and antibacterial screening, while isoniazid and pyrazinamide were used as references for antimycobacterial activity. Furthermore, three Quantitative Structure Activity Relationship (QSAR) models were built to explore the structural requirements controlling the different activities of the prepared bis-hydrazones.  相似文献   
58.
Dialysis disequilibrium syndrome (DDS) is a rare central nervous system (CNS) disease which develops in patients receiving hemodialysis (HD). Although it has been reported in patients receiving chronic HD, DDS is more common during or immediately after the first HD treatment. The exact incidence of DDS is unknown. Death in DDS is an extremely rare phenomenon and to the best of our knowledge only 9 cases have been reported showing this association. We present a unique case of a 42‐year‐old female on chronic HD, and no prior history of CNS disease, who developed brain death in the setting of DDS 2 hours into the dialysis treatment. A literature review of all previously reported cases was performed.  相似文献   
59.
53Mn radionuclide (T(1/2) = 3.7 x 10(6) y) is produced through the interaction of cosmic rays. Measurements of concentrations of 53Mn in rocks might help to understand Earth surface processes that occurred in time periods not accessible with other cosmogenic nuclides. Only accelerator mass spectrometry (AMS) can determine such ultratrace levels of 53Mn. The main interference in the detection of 53Mn by AMS is its stable isobar 53Cr, which is roughly approximately 10(12) times more abundant in nature. A prerequisite of any AMS measurement of 53Mn in geological samples is therefore chromium separation by an efficient chemistry. Thus, we have developed a method for the separation of chromium and manganese by using a radiometric simulation. The separation procedure was monitored by 51Cr (T(1/2) = 27.70 d) and 52Mn (T(1/2) = 5.59 d) as the corresponding radiotracers for chromium and manganese, respectively. The separation studies were performed by a liquid-liquid extraction technique using trioctylamine (TOA) diluted in cyclohexane. A high separation factor (approximately 16 000) for Mn and Cr can be obtained at optimal conditions of 0.8 M TOA and 9 M HCl. The developed method has been found equally applicable for real geological samples such as manganese crusts, lava, and sediment samples. Therefore, the method offers an important tool to improve 53Mn measurements by AMS.  相似文献   
60.
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