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21.
Cookie fillings are typically composed of sugar (60%–80%) and fat (20%–40%). The fat in these fillings is known as shortening, which currently has high levels of saturated fatty acids (SFA) and, in some cases, trans fatty acids (TFA). This makes the nutritional profile of this product a reason for concern, especially considering that the target audience for cookies is children. This study thus aimed to replace the commercial shortening in these fillings with oleogels made of soybean oil (SB) and high oleic sunflower oil (SF) structured with candelilla wax (CLX), monoglycerides (MG), and hard fat (HF), in different concentrations ranging from 5%–10% of the total structuring content. The complete replacement of shortening with oleogel reduced the amount of TFA by 100% and the amount of SFA by 50%–80%. The quantities of MG and HF greatly influenced the structuring of the product because the higher the concentrations (≥3%), the better the formation of the structured network, with good aeration, greater hardness, and less oil loss, compared with the standard with shortening. The samples that achieved physical properties similar to those of the control sample were samples 3:3:3 and 1:4:5 (CLX:MG:HF). These showed similar oil loss at T0 (~4.5%), and microstructure before and after temperature oscillations and closer consistency (~400 gF/cm2) and adhesiveness (50 gF. s) to the RP (800 gF/cm2 and 75 gF. s). Although MG and HF are not good structuring elements alone as the CLX, they formed a network that is connected by hydrogen bonds with the sugar molecules that were resistant to stirring and thermal changes, which makes this system a potential replacement for shortenings in cookie fillings application.  相似文献   
22.
The primary antioxidant tert-butylhydroquinone (TBHQ) and an alternative additive, named 1,4-bis(ethylamino)-9,10-anthraquinone, were mixed to yield a potent blend able to be used in the field of biodiesel preservation. Physicochemical parameters such as peroxide value, total acid number, density and induction period were used to evaluate the effectiveness of the combination in stabilising soybean biodiesel during the accelerate storage period of degradation. The induction period values were also used to calculate the occurrence of synergistic effect, and it was observed a high percentage of synergism for the combined additives. The results showed that the presence of target alternative additive also enables lower the concentration of the primary antioxidant (TBHQ) in the blend. The cost-effective comparison was evaluated, and it was verified that the final cost of biodiesel can also be lowered, since the amount of additives (in the blend) required to meet the biodiesel specifications was reduced between 70 and 88%.  相似文献   
23.
The choice of fermentation system during cachaça production can greatly influence the chemical composition of the beverage. In this work, Saccharomyces cerevisiae strains were selected based on fermentative properties and used as starters to produce alembic cachaça. In distillery scale production, the selected yeast strains exhibited greater adaptiblity to the fermentation environment and hence remained predominant throughout the process. Electrospray ionization mass spectrometry in the negative ion mode revealed that most of the compounds present in the must are different from those formed in the distillate for both cachaças obtained from spontaneous and selected strains. However, beverages produced using selected strains showed greater similarity in chemical profiles than those produced from spontaneous strain fermentation. Moreover, a smaller number of ions were detected in beverages produced by selected strain than from spontaneous strain fermentation. Our results indicate that the selected S. cerevisiae strains evaluated are able to produce cachaças less subject to variation in chemical composition. This could potentially improve brand consistency and thus commercial viability, particularly in the international market.  相似文献   
24.
Nanoparticles of magnetite passivated with gelatin and starch were synthesised using a co‐precipitation technique. The nanoparticles were characterised using ultraviolet–visible (UV–vis), dynamic light scattering (DLS), Zeta potential, transmission electron microscope (TEM), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The UV–vis spectra showed characteristic surface plasmon resonance of magnetite nanoparticles. The DLS results showed the nanoparticles to have average hydrodynamic diameters of 138 ± 2 and 283 ± 21 nm for particles passivated with gelatin and starch, respectively. The stability in a colloidal solution was greater in nanoparticles passivated with gelatin than nanoparticles obtained with starch, as can be seen by their Zeta potential value (−31 ± 2 and −16 ± 0.5 mV, respectively). According to the TEM evaluation, the use of gelatin allowed to obtain nanoparticles with a spherical morphology and an average size of 10 ± 2 nm. However, when using starch the nanoparticles exhibited diverse morphologies with an average size of 25 ± 7 nm. The XRD results confirmed the crystalline structure of the samples, which showed crystallite sizes of 14.90 and 24.43 nm for nanoparticles passivated with gelatin and starch, respectively. FTIR analysis proved the establishment of interactions between functional groups of biopolymers and magnetite nanoparticles.Inspec keywords: crystallites, nanofabrication, ultraviolet spectra, gelatin, surface plasmon resonance, transmission electron microscopy, scanning electron microscopy, visible spectra, X‐ray diffraction, iron compounds, electrokinetic effects, particle size, colloids, nanoparticles, nanomedicine, precipitation (physical chemistry), light scattering, magnetic particles, Fourier transform infrared spectra, nanomagnetics, filled polymers, nanocompositesOther keywords: magnetite nanoparticles, gelatin, starch, characteristic surface plasmon resonance, capping agents, passivation, co‐precipitation technique, ultraviolet–visible spectra, zeta potential value, dynamic light scattering, DLS, transmission electron microscopy, TEM, X‐ray diffraction, XRD, Fourier transform infrared spectroscopy, FTIR, surface plasmon resonance, hydrodynamic diameters, colloidal solution, spherical morphology, crystalline structure, crystallite size, biopolymers, Fe2 O3   相似文献   
25.
The maintenance of ecosystem goods and services, i.e. natural capital, is the basic guarantee of environmental security that aims to evaluate the level of threats to the actual flux of natural capital. This research concerns a natural protected area in southern Italy and aims at (1) assessing the temporal dynamics of land-use and land-cover mosaics, and indirectly of the natural capital they support, using the economic valuation of ecosystem goods and services as surrogate; and (2) ascertaining whether all the past environmental conservation policies have fostered the natural capital, reducing or increasing its security. To these purposes, orthorectified aerial photos, referring to July 1954, 1987, 1997 and 2004, were used to analyze the landscape change trajectory and the consequent change of natural capital flux. Surprisingly the results showed that not all environmental conservation policies have played an equal role in fostering the maintenance of natural capital. This research highlighted that the recognition of the natural value of a site according to the European Directives is not sufficiently effective for the conservation of the natural capital, while the presence of a local management authority setting some limits on human activities that cause landscape changes, can increase the security of natural capital. This is of particular relevance considering that in each European partner country there is a great number of areas that are recognized for their natural value but that, at the moment, are not protected at a local level with any measure aimed at mitigating human impact.  相似文献   
26.
The by-products of the food industry can be used as nutrient source to improve the nutritional characteristics of other food products. This study aimed to investigate the chemical composition, antioxidant activity and phenolic compound content of organic grape peel flour in cookies using response surface methodology. Composition analysis using different assays (DPPH, ABTS, FRAP, ORAC) revealed that this flour was low in calories (180.22 ± 0.25 kcal%), with low dietary fibre content (50.10 ± 0.01 g%) and high antioxidant capacity. The total phenolic compound analysis showed high values of phenolic compounds (1063.58 ± 8.09 mg%), consisting of resveratrol (54.27 ± 0.79 mg%), epicatechin (43.94 ± 0.90 mg%) and chlorogenic acid (35.70 ± 1.47 mg%). A 23 factorial experimental design was formulated to optimise the ingredients for cookie production. The resulting cookies presented high acceptance and good sensory properties, confirming that organic grape flour did not interfere with product acceptability. Thus, cookies with an acceptable quality and improved nutrition can be prepared using organic grape peel flour.  相似文献   
27.
28.
The effect of thermal processing and the berry cultivar has been the subject of several studies, to serve as a basis for the least possible loss of bioactive compounds and antioxidant capacity. In Brazil, there are numerous blackberry cultivars under cultivation, and in this context, the aim of this work was to study how the bioactive compound contents and antioxidant capacity of blackberry jelly were influenced by the cultivars (Guarani, Brazos, Comanche, Tupy, Cherokee, Caingangue and Choctaw). Analysis was made of 7 fresh blackberry cultivars and 7 blackberry jelly formulations. Analysis of antioxidant activity, total phenolics, total anthocyanins and ascorbic acid was performed. It was verified that the contribution of the heat sensitive antioxidants compounds is considerable in all blackberry cultivars, and the degradation of these compounds was significantly different between the different blackberry cultivars. The Brazos and Caingangue cultivars stand out as undergoing the lowest losses in processing, resulting in jellies richer in bioactive compounds and higher antioxidant capacity.  相似文献   
29.
Metformin is the most used biguanide drug for the treatment of type 2 diabetes mellitus. Despite being mostly known for its hepatic anti-gluconeogenic effect, it is also known to modulate microRNAs (miRNAs, miRs) associated with metabolic diseases. The latter mechanism could be relevant for better understanding metformin’s mechanisms underlying its biological effects. In the current work, we found that metformin increases miR-378a-3p expression (p < 0.002) in C2C12 myoblasts previously exposed to hyperglycemic conditions. While the inhibition of miR-378a-3p was shown to impair metformin’s effect in ATP production, PEPCK activity and the expression of Tfam. Finally, mitophagy, an autophagic process responsible for the selective degradation of mitochondria, was found to be induced by miR-378a-3p (p < 0.04). miR-378a-3p stimulated mitophagy through a process independent of sestrin-2 (SESN2), a stress-responsible protein that has been recently demonstrated to positively modulate mitophagy. Our findings provide novel insights into an alternative mechanism of action of metformin involving miR-378a-3, which can be used in the future for the development of improved therapeutic strategies against metabolic diseases.  相似文献   
30.
Computing the solar vector   总被引:2,自引:0,他引:2  
High-concentration solar thermal systems require the Sun to be tracked with great accuracy. The higher the system concentration, the greater this accuracy must be. The current trend in solar concentrator tracking systems is to use open-loop controllers that compute the direction of the solar vector based on location and time. To keep down the price of the tracking system, the controller is based on a low-cost microprocessor. These two facts impose important restrictions on the Sun position algorithm to be used in the controller, as it must be highly accurate and efficiently computable at the same time. In this paper, various algorithms currently available in the solar literature are reviewed and a new algorithm, developed at the Plataforma Solar de Almería, which combines these two characteristics of accuracy and simplicity, is presented. The algorithm allows of the true solar vector to be determined with an accuracy of 0.5 minutes of arc for the period 1999–2015.  相似文献   
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