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1.
Six men were accidentally exposed to NO2 when they were changing a propeller using a gas burner in the poorly ventilated hold of a ship. All of them were admitted to hospital with shortness of breath and cough. Chest X-ray on admission revealed diffuse, patchy and infiltrative shadows, leading to the diagnosis of pulmonary edema in all five patients. Steroid therapy was effective and followed by a quick recovery in all patients. None developed third phase manifestations characterized pathologically by bronchiolitis obliterans.  相似文献   
2.
In enology, alcoholic fermentation is a complex process involving several mechanisms. Slow and incomplete alcoholic fermentation is a chronic problem for the wine industry and factors leading to sluggish and stuck fermentations have been extensively studied and reviewed. The most studied cause of sluggish and stuck fermentation is the nitrogen content limitation. Nevertheless, other factors, such as temperature of fermentation and sugar concentration can affect the growth of yeasts. In this study we modelled the yeast growth‐cycle in wine model system as a function of temperature, sugar and ammonium concentrations; the individual effects and the interaction of these factors were analysed by means of a quadratic response surface methodology. Cell concentrations and weight loss were monitored in the whole wine fermentation process. The results of central composite design show that lower is the availability of nitrogen, higher is the cell growth rate; moreover, initial nitrogen concentration also influences survival time of Saccharomyces cerevisiae.  相似文献   
3.
Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine.  相似文献   
4.
Once merely thought of as the protein responsible for the overall physical nature of the human immunodeficiency virus type 1 (HIV-1), the Gag polyprotein has since been elucidated to have several roles in viral replication and functionality. Over the years, extensive research into the polyproteins’ structure has revealed that Gag can mediate its own trafficking to the plasma membrane, it can interact with several host factors and can even aid in viral genome packaging. Not surprisingly, Gag has also been associated with HIV-1 drug resistance and even treatment failure. Therefore, this review provides an extensive overview of the structural and functional roles of the HIV-1 Gag domains in virion integrity, functionality and infectivity.  相似文献   
5.
The effect of excess lauric and oleic acids on the conductivity and on the pH of 0.2–0.02N potassium laurate and 0.1–0.01N sodium oleate systems was observed. The decrease in the specific conductivity corresponded with the formation of the acid soaps, 2KL·HL, KL·HL, 2NaOl·HOl, NaOl·HOl, and the mixed soaps 2KL·HOl and 2NaOl·HL. The mixed soaps resemble the oleates in appearance. All of these systems, even with 100 or 150 moles per cent excess acid, were slightly alkaline.  相似文献   
6.
A Li ion polymer battery pack for road vehicles (48 V, 20 Ah) was tested by charging/discharging tests at different current values, in order to evaluate its performance in comparison with a conventional Pb acid battery pack. The comparative analysis was also performed integrating the two storage systems in a hydrogen fuel cell power train for moped applications. The propulsion system comprised a fuel cell generator based on a 2.5 kW polymeric electrolyte membrane (PEM) stack, fuelled with compressed hydrogen, an electric drive of 1.8 kW as nominal power, of the same typology of that installed on commercial electric scooters (brushless electric machine and controlled bidirectional inverter). The power train was characterized making use of a test bench able to simulate the vehicle behaviour and road characteristics on driving cycles with different acceleration/deceleration rates and lengths. The power flows between fuel cell system, electric energy storage system and electric drive during the different cycles were analyzed, evidencing the effect of high battery currents on the vehicle driving range. The use of Li batteries in the fuel cell power train, adopting a range extender configuration, determined a hydrogen consumption lower than the correspondent Pb battery/fuel cell hybrid vehicle, with a major flexibility in the power management.  相似文献   
7.
The main topic of this study was to study how cell surface hydrophobicity (CSH) could change in response to pH, temperature and inulin; Lactobacillus acidophilus La‐5 was used as a model microorganism. pH, temperature, inulin and incubation time (exposure to prebiotic or incubation at pH 4.0 and 9.0) were combined through a full factorial design and a Central Composite Design; the results were analysed using a multifactorial anova (first step) and a stepwise regression (second step). Temperature and pH significantly affected CSH: an increase in the temperature determined a significant increase in CSH, whereas the correlation pH vs. CSH was negative, as an increase in pH caused a significant decrease in CSH. Inulin played a significant role, but its effect could be influenced by temperature, pH and exposure time. This study is the first approach on the effects of some environmental factors on CSH and suggests that the culturing conditions and/or the exposure to some prebiotics could modify it with positive or negative effects.  相似文献   
8.
An experimental analysis was conducted on a 30 kW fuel cell power train with the aim to elucidate specific concerns of dynamic behaviour of hydrogen fuel cells in automotive applications. The study was conducted on a dynamic test bench able to simulate the behaviour of the reference vehicle, a minibus for historical centres collective service, on predefined driving cycle. The transient performance of the fuel cell system was firstly investigated without electric drive, using as load electric resistances electronically controlled. Experimental data were collected during warmup phases characterized by two acceleration slopes (150 W/s and 1500 W/s) and during a sequence of dynamic test cycles characterized by a very high acceleration slope of about 6 kW/s. The role of reactant feeding, humidification and cooling systems was investigated during all tests evaluating the performance during the transient steps in terms of cell voltage uniformity, expressed by the coefficient of variation Cv, used as statistical indicator. A driving cycle characterized by stop-and-go pattern and acceleration slopes compatible with a real utilization of the reference vehicle was finally adopted for tests on the overall power train. The results demonstrated a very good dynamic performance of the fuel cell stack as evidenced by the analysis of Cv, which resulted lower than 2.5% in all investigated working conditions, and by the overall power train efficiency which resulted about 30% with fuel cell system efficiency close to 50%.  相似文献   
9.
The topic of this paper is the investigation of the antibacterial effect of ultrasound (US) towards Salmonella enterica in a rice beverage. The beverage was inoculated at different levels (8 and 5 log CFU/mL) and US-treated; then, a challenge test under refrigeration was carried out. The maximum net power of the equipment was 130 W; the treatment was carried out at 40–100% of the net power, for 2–10 min; the pulse was set to 2–10 s. For both the inoculum levels, power and time were the most important factors for the antimicrobial effect towards S. enterica. The combinations resulting in the highest inactivation of the pathogen were tested during the challenge test at 4 °C, and in some combinations, S. enterica remained below the detection limit for 13 days.  相似文献   
10.
In addition to the production of secondary electrons and secondary ions, characteristic x‐ray emission may also result from ion/solid interactions and is the basis for the well‐known analysis technique referred to as particle‐induced x‐ray emission. Characteristic x‐rays may be emitted by either bombardment by MeV protons or heavy ions of a few keV. The advantage to heavy ions is that the x‐ray yield is confined to the region near the surface defined by the collision cascade. An advantage of heavy ion‐induced x‐ray emission over electron‐induced x‐ray emission is that the Bremsstrahlung is potentially orders of magnitude lower. Thus, ion‐induced x‐ray spectra may provide for superior peak‐to‐noise ratios, and there‐fore, offers trace element sensitivity compared with elec‐tron‐induced x‐ray emission. In addition, the near surface ion/solid interactions also allow for the possibility of surface analysis or depth profiling. A Dual Beam instrument was used to collect focused ion beam‐induced x‐ray (FIBIX) spectra. The acquisition of characteristic x‐rays from targets via FIBIX is demonstrated and compared with scanning electron microscopy‐induced x‐ray energy dispersive spectroscopy spectra and is consistent with the theory described above.  相似文献   
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