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121.
ABSTRACT: The aim of this work was to describe the sensory profile of wine vinegars aged with oak chips (accelerated aging) compared with those elaborated by a traditional method (sherry vinegar). Two types of oak chips (American and French) were used to perform sample infusions. The chips were subjected to toasting to simulate the heating effect during oak board bending in cask construction. Ten sensory parameters were selected to describe the vinegars with 11 trained panelists. Sensory profiles were compared and sensorial differences observed among the samples analyzed. These differences are largely associated with the pungent sensation rather than the sensory attributes generated from the oak wood.  相似文献   
122.
Fruits such as Prosopis pod have been food sources (patay, arrope, chicha or aloja) of inhabitants of arid and semi-arid lands in South America. The aims of the present study were determine some nutritional and functional properties as well as genotoxicity of flour obtained from Prosopis ripe pods that were submitted to different processing. Sucrose constituted the main sugar for flours obtained from Prosopis alba and Prosopis nigra. Decoctions and macerations showed around 2.9% and 1.4% of soluble proteins, respectively. The highest free phenolics, flavonoids and condensed tannins contents were observed in aqueous extractions with heating. None of the samples presented phytic acid levels high enough to constitute a nutritional problem. Antioxidant activity (AA) was evaluated by DPPH, ABTS and β-carotene bleaching assays. Results showed that the antioxidant potential was significantly higher in flour obtained from P. nigra pods than in that from P. alba pods, and it was also higher in aqueous extracts than in alcoholic ones. Data obtained suggests that compounds responsible for AA are thermostable; therefore, Prosopis flour might be capable of retaining a significant amount of antioxidant capacity after heating. Prosopis extracts did not show any mutagenic effect with and without metabolic activation. Prosopis flour proved to be a non conventional, novel and rich source of antioxidant compounds that could help to prevent pathologies associated with oxidative stress.  相似文献   
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Cylindrospermopsis raciborskii occurs predominantly in tropical to subtropical freshwaters but appears to be spreading to temperate regions. After the hurricanes of 2005, a bloom of this organism took place in Lake Dauterive and Lake Fausse Pointe in Louisiana. The cyanobacterium dominated the phytoplankton community for three months. Of the three known morphotypes (straight, coiled and spiral) only coiled and spiral were found. In June 2006, 60% of the organisms were of the spiral morphotype but the relative abundance of this morphotype decreased dramatically within the month of June. However, the average density for both morphotypes remained the same until September. Densities (up to 160,000 cells/mL) significantly exceeded the threshold for toxicity. Because the sampled region offers optimal light and nutrient conditions, it is likely that C. raciborskii has been established in this region and future blooms can be expected. Therefore, a monitoring program should be implemented.  相似文献   
125.
In energy harvesting wireless sensor networks, the sensors are able to harvest energy from the environment to recharge their batteries and thus prolong indefinitely their activities. Widely used energy harvesting systems are based on solar cells, which are predictable (i.e., their energy production can be predicted in advance). However, since the energy production of solar cells is not constant during the day, and it is null at night time, these systems require algorithms able to balance the energy consumption and production of the sensors. In this framework, we approach the design of a scheduling algorithm for the sensors that selects among a set of available tasks for the sensors (each assigned with a given quality of service), in order to keeping the sensors energy neutral, i.e., the energy produced during a day exceeds the energy consumed in the same time frame, while improving the overall quality of service. The algorithm solves an optimization problem by using a greedy approach that can be easily implemented on low-power sensors. The simulation results demonstrate that our approach is able to improve the quality of the overall scheduling plan of all networked sensors and that it actually maintains them energy neutral.  相似文献   
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In the last few years we have analysed the factors that affect the structures and luminescence properties of Au(I) compounds, specifically in relation with the presence of aurophilic contacts and their application as cation probes. EXAFS studies have allowed us to obtain for the first time direct structural data of dissolved Au(I) compounds. An overview of the work reported to date is presented here. The optical properties of complex [Au2Cl2(μ-dpephos)] (dpephos =bis(2-diphenylphosphino) phenylether, 1) have been revisited and new results are now included. New aspects on the use of the complexes as Ag(I) probes are also discussed.  相似文献   
128.
Hearing loss affects many people worldwide and occurs often as a result of age, ototoxic drugs and/or excessive noise exposure. With a growing number of elderly people, the number of people suffering from hearing loss will also increase in the future. Despite the high number of affected people, for most patients there is no curative therapy for hearing loss and hearing aids or cochlea implants remain the only option. Important treatment approaches for hearing loss include the development of regenerative therapies or the inhibition of cell death/promotion of cell survival pathways. The mammalian target of rapamycin (mTOR) pathway is a central regulator of cell growth, is involved in cell survival, and has been shown to be implicated in many age-related diseases. In the inner ear, mTOR signaling has also started to gain attention recently. In this review, we will emphasize recent discoveries of mTOR signaling in the inner ear and discuss implications for possible treatments for hearing restoration.  相似文献   
129.
In this study the effect of ozone and peroxone on the structure of Hymenolepis nana eggs at different pH (5, 7 and 10) was evaluated. Experiments were conducted with an ozone dose of 1.1 mg/min for 60 min; peroxone tests were done with the same conditions of ozonation process plus 0.33 mL of 33% hydrogen peroxide. Studies with scanning and transmission electron microscopy did not show ultrastructural changes after the treatment with ozone and peroxone at pH 5 and 7, but at pH 10 the eggs lost their external layer, making them more vulnerable.  相似文献   
130.
The catalytic ozonation of fenofibric and clofibric acids and the herbicides atrazine and linuron was studied using titanium dioxide, alumina, and manganese oxide supported on activated alumina and on silica SBA-15. The organics studied did not adsorb significantly either in wastewater or in phosphate-buffered water. The catalysts did not modify the rate of the hydroxyl-mediated ozonation with respect to the homogeneous value. The mode of action of metal oxide catalysts would be an enhanced generation of oxidant species from the catalytic decomposition of ozone. All catalysts increased the efficiency in the production of hydroxyl radicals from ozone.  相似文献   
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