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61.
Lupine has the potential to be a new domestic source of vegetable protein due to its comparable quality to the commonly used soy proteins. However, the bioprocessing that take place in the production of wheat bread with non‐conventional flours could play an important role. The wholemeal Lupinus angustifolius and Lupinus luteus flours were fermented by bacteriocin‐producing strain of Pediococcus acidilactici. The effect of lupine flour supplementation on wheat bread quality, sensory and safety criteria was studied. The lupine additives significantly decreased the quality of bread. The fermented L. luteus flour (10% of flour basis) had a slightly higher positive effect on the specific volume and crumb porosity (5.4%) and lowering of crumb hardness (9.5%) than those of L. angustifolius. In contrary, consumers rated higher for bread with L. angustifolius sourdough, which contributed to a stronger taste score. The levels of tyramine, histamine and putrescine (32.6–215.8, 20.8–96.7 and 33.7–195.2 mg kg?1, respectively) do not present a health risk for consumers due to their relatively low levels in lupine fermented products. Bioprocessing used for wheat bread production with lupine flour additives could improve the nutritional profile of bread without increasing the risk of biogenic amine formation.  相似文献   
62.
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   
63.
Postevaluation (PE) of an information system is probably the most neglected activity along the system life cycle. However, PE is essential for making improvements to existing systems and generating standard practices for future information system development projects. Based on actual experience, the 12-step procedure described here can help organizations realize both the future and immediate benefits that PE offers.  相似文献   
64.
This paper is concerned with the problem of optimal assignment of data to sites in a distributed relational database. It is shown that in general the optimal allocation will require exponential time in terms of the input. Several heuristic algorithms that can be applied to various constraints and which provide feasible, near optimal results, as well as a model that determines the “best” assignment for a given input out of several optimal and near optimal assignments have been developed. The model is shown to be efficient, to require polynomial time, to be practical in terms of feasible inputs and to achieve assignments with near minimal global and local costs.  相似文献   
65.
Should a coal-fired power plant be replaced or retrofitted?   总被引:1,自引:0,他引:1  
In a cap-and-trade system, a power plant operator can choose to operate while paying for the necessary emissions allowances, retrofit emissions controls to the plant, or replace the unit with a new plant. Allowance prices are uncertain, as are the timing and stringency of requirements for control of mercury and carbon emissions. We model the evolution of allowance prices for SO2, NOx, Hg, and CO2 using geometric Brownian motion with drift, volatility, and jumps, and use an options-based analysis to find the value of the alternatives. In the absence of a carbon price, only if the owners have a planning horizon longer than 30 years would they replace a conventional coal-fired plant with a high-performance unit such as a supercritical plant; otherwise, they would install SO2 and NOx, controls on the existing unit. An expectation that the CO2 price will reach $50/t in 2020 makes the installation of an IGCC with carbon capture and sequestration attractive today, even for planning horizons as short as 20 years. A carbon price below $40/t is unlikely to produce investments in carbon capture for electric power.  相似文献   
66.
Carbon capture and storage (CCS) can significantly reduce the amount of CO(2) emitted from coal-fired power plants but its operation significantly reduces the plant's net electrical output and decreases profits, especially during times of high electricity prices. An amine-based CCS system can be modified adding amine-storage to allow postponing 92% of all its energy consumption to times of lower electricity prices, and in this way has the potential to effectively reduce the cost of CO(2) capture by reducing the costs of the forgone electricity sales. However adding amine-storage to a CCS system implies a significant capital cost that will be outweighed by the price-arbitrage revenue only if the difference between low and high electricity prices is substantial. In this paper we find a threshold for the variability in electricity prices that make the benefits from electricity price arbitrage outweigh the capital costs of amine-storage. We then look at wholesale electricity markets in the Eastern Interconnect of the United States to determine profitability of amine-storage systems in this region. Using hourly electricity price data from years 2007 and 2008 we find that amine storage may be cost-effective in areas with high price variability.  相似文献   
67.
This article analyses the main problems and challenges of corporate social responsibility in energy sector in Baltic States. Development of socially responsible business in energy sector can provide for the implementation of sustainable energy development without state interventions. This voluntary measure implemented by energy enterprises can ensure efficient public–private partnership in achieving sustainable development targets. The analysis of corporate social responsibility development in energy sector of Baltic States is provided and positive impact of corporate social responsibility on sustainable energy development is evaluated.  相似文献   
68.
69.
A set of 13 US based experts in post-combustion and oxy-fuel combustion CO2 capture systems responded to an extensive questionnaire asking their views on the present status and future expected performance and costs for amine-based, chilled ammonia, and oxy-combustion retrofits of coal-fired power plants. This paper presents the experts' responses for technology maturity, ideal plant characteristics for early adopters, and the extent to which R&D and deployment incentives will impact costs. It also presents the best estimates and 95% confidence limits of the energy penalties associated with amine-based systems. The results show a general consensus that amine-based systems are closer to commercial application, but potential for improving performance and lowering costs is limited; chilled ammonia and oxy-combustion offer greater potential for cost reductions, but not without greater uncertainty regarding scale and technical feasibility.  相似文献   
70.
It is commonly understood that households must change their behavior to reduce problems related increased energy consumption and climate change therefore in the search of cheap GHG emission reduction measures households are an important target group because they are responsible for more than 20% of total energy consumption in developed countries. In addition waste management and responsible consumption of products are the key issues in GHG emission reduction.The aim of the paper is to assess GHG emission reduction potential in households in terms of behavioral changes towards sustainable consumption. The review of literature on analysis of households behavioral changes impact on GHG emission reduction was performed; the daily survey of household agenda and energy use records were performed in Lithuania for two scenarios – baseline and GHG emission reduction scenario including energy saving. GHG emission reduction potential in household was assessed based on daily survey data and energy consumption records by applying carbon calculator based on modified coefficients. Evaluated GHG emission reduction potential in households was compared with GHG emission reduction potentials in other sectors of Lithuania. Based on analysis performed in the paper the tools to promote household behavioral changes towards sustainable consumption were proposed.  相似文献   
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