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11.
12.
Buildings play a key role in total world energy consumption as a consequence of poor thermal insulation characteristics of facade materials. Among the elements of a typical building envelope, windows are responsible for the greatest energy loss because of their notably high overall heat transfer coefficients. About 60% of heat loss through the building fabric can be attributed to the glazed areas. In this respect, novel cost‐effective glazing technologies are needed to mitigate energy consumption, and thus to achieve the latest targets toward low/zero carbon buildings. Therefore in this study, three unique glazing products called vacuum tube window, heat insulation solar glass and solar pond window which have recently been developed at the University of Nottingham are introduced, and thermal performance analysis of each glazing technology is done through a comparative experimental investigation for the first time in literature. Standardized co‐heating test methodology is performed, and overall heat transfer coefficient (U‐value) is determined for each glazing product following the tests carried out in a calibrated environmental chamber. The research essentially aims at developing cost‐effective solutions to mitigate energy consumption because of windows. The results indicate that each glazing technology provides very promising U‐values which are incomparable with conventional commercial glazing products. Among the samples tested, the lowest U‐value is obtained from the vacuum tube window by 0.40 W/m2K, which corresponds to five times better thermal insulation ability compared to standard air filled double glazed windows. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
13.
Effects of pomegranate sauce on quality of marinated anchovy during refrigerated storage 总被引:1,自引:0,他引:1
Effects of pomegranate sauce on the quality of marinated anchovy during storage at 4 °C were investigated. Anchovy were marinated with 30 g/L acetic acid and 150 g/L salt, put into glass jars, filled with either sunflower oil or pomegranate sauce and stored at 4 °C. Total volatile basic nitrogen (TVB-N) and trimethylamine (TMA-N) values increased during the storage. Higher values for free fatty acid (FFA), conjugated diens (k-dien) and para-anisidine (p-Av) were found in samples with sunflower oil than those with pomegranate sauce. Samples in pomegranate sauce showed better oxidative stability. Higher taste and flavour and lower appearance scores were found for samples in pomegranate sauce than those samples in sunflower oil. It was found that pomegranate sauce was as least effective as the traditional sunflower oil to keep quality. Pomegranate sauce also produced desirable taste and flavour but the coloration should be studied in further studies. 相似文献
14.
Long‐term testing of a high temperature polymer electrolyte membrane fuel cell: The effect of reactant gases
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F. Javier Pinar Nadine Pilinski Peter Wagner 《American Institute of Chemical Engineers》2016,62(1):217-227
The investigations have been conducted with different oxidants and fuels with the aim of determining the state‐of‐the‐art of commercially available high temperature polymer electrolyte fuel cells based on polybenzimidazole for its application in combined heat and power generation systems. The fuel cell test performed with synthetic reformate (?63 μV/h) showed an increase of anode charge and mass transfer resistances. This behavior has suggested that CO may be generated from the CO2 included in the synthetic reformate via reverse water gas shift reaction. The fuel cell test performed with pure O2 developed the highest degradation rates (?70 μV/h) due to fast oxidative degradation of membrane electrode assembly materials such as cathode catalyst and membrane. Fuel cell operation with H2/air exhibited the lowest degradation rates (?57 μV/h) and it requires longer investigating times to identify the different degradation mechanisms. Moreover, fuel cell tests performed with air suggested longer break‐in procedures to complete catalyst activation and redistribution of electrolyte. © 2015 American Institute of Chemical Engineers AIChE J, 62: 217–227, 2016 相似文献
15.
Incorporation of [14C] from acetoacetate, D(-)- and L(+)-3-hydroxybutyrate, glucose, glutamine, acetate and palmitate in cellular lipids were
studied in cultures in human diploid fibroblasts (HDF). The results showed that acetoacetate was 2–10 times more effective
as a lipogenic precursor than was either D- or L-3-hydroxybutyrate. Its extent of incorporation into lipids was 2- to 8-fold
more than the other precursors examined under conditions when the overall rates of nonsaponifiable and saponi-fiable lipogenesis
as measured by3H2O incorporation were essentially unchanged. Acetoacetate supported both saponifiable and nonsaponifiable lipid syntheses with
half-saturation values (Km app.) of 185 μM and 30 μM, respectively. Glucose stimulated acetoacetate incorporation into lipids whereas, conversely, acetoacetate
inhibited [14C] glucose incorporation into lipids. The presence of low density lipoproteins (LDL) cholesterol (@40 μg cholesterol/mL) inhibited
the incorporation of [14C] from acetoacetate 56% into nonsaponifiable lipids; the inhibition was consistently higher (75%) when [14C] glucose or glutamine were the precrusors. The loss of 3-hydroxy-3-methyl-glutaryl CoA (HMG CoA) reductase activity upon
addition of LDL-cholesterol was greater than the suppression of [14C] incorporation from acetoacetate or glucose into nonsaponifiable lipids. In the presence of glucose, [14C] acetoacetate was incorporated into 3-βOH sterols (digitonin precipitable). 7.7±1.1 times more effectively than was [14C] glucose. The results suggest that HDF would be a suitable model to investigate the effects of various precrusors of HMG
CoA on the rate of cholesterol biosynthesis. 相似文献
16.
Basil T. Wong M. Pinar Mengüç 《International Journal of Heat and Mass Transfer》2009,52(11-12):2632-2645
A detailed numerical simulation for electron-beam heating of n-doped silicon is presented. Electron-beam penetration is modeled using electron-beam transport equation (EBTE). The EBTE is solved by using a Monte Carlo (MC) method to determine the electron deposition distributions, including electron density deposition and optical phonon generation. Electron and phonon temperatures of the film are then determined using electron–phonon hydrodynamic equations (EPHDEs) coupled with the deposition distributions obtained from the MC simulation. The combined EBTE and EPHDEs results indicate that an electron beam creates a depletion region near the surface of incidence and causes non-equilibrium between electron and phonon temperatures. 相似文献
17.
Pinar Yerlikaya Nalan Gokoglu 《International Journal of Food Science & Technology》2010,45(2):252-257
The aim of this study was to investigate inhibition effects of green tea and grape seed extracts on lipid oxidation in bonito (Sarda sarda) fillets during frozen storage. Dried and powdered green tea and grape seed were extracted using ethanol. Extract solutions of 1 g 100 g?1 were prepared using concentrated extracts and distilled water. Bonito fillets were divided into two groups. The first group was dipped into extract solutions and then frozen. The second group of fillets was glazed by extract solutions. Oxidation increased progressively through the storage period. 2‐Thiobarbituric acid and para‐anisidine values of samples treated with green tea and grape seed extracts remained at low levels. Both plant extracts displayed successful effects in delaying lipid oxidation compared to the control groups. The best results were obtained by extract treatment of fillets before freezing. 相似文献
18.
To characterize milk through light-scattering measurements, a semianalytical radiative transfer model was used to simulate the backscatter of light in milk having homogenized fat levels from 0.05 to 3.2 wt. %. The input parameters to the model include the incident wavelength, refractive index of particles and medium, and particle number densities. By varying the wavelength, we can obtain a reasonable fit between experimental data and the model for lower fat milks. Results indicate that the model is most sensitive to the particle diameter and size distribution and less sensitive to the number and index of refraction of the particles. 相似文献
19.
The bandwidth minimization problem has a long history and a number of practical applications.
In this paper we introduce a natural extension of bandwidth to partially ordered layouts.
We consider this extension from three main viewpoints: graph searching,
tree decompositions, and elimination orderings.
The three graph parameters pathwidth, profile, and bandwidth related to linear layouts
can be defined by variants of graph searching using a standard fugitive.
Switching to an inert fugitive, the two former parameters are extended to
treewidth and fill-in, and our first viewpoint considers the
analogous tree-like extension that arises from the bandwidth variant.
Bandwidth also has a definition in terms of ordered path decompositions,
and our second viewpoint extends this in a natural way to ordered
tree decompositions.
In showing that both extensions are equivalent we employ the third viewpoint of
elimination trees, as used in the field of sparse matrix computations.
We call the resulting parameter the treespan of a graph and
prove some of its combinatorial and algorithmic properties. 相似文献
20.
Fluorescence correlation spectroscopy (FCS) is adapted for a new procedure to detect trace amounts of Escherichia coli in water. The present concept is based on convective diffusion rather than Brownian diffusion and employs confocal microscopy as in traditional FCS. With this system it is possible to detect concentrations as small as 1.5 x 10(5) E. coli per milliliter (2.5 x 10(-16) M). This concentration corresponds to an approximately 1.0-nM level of Rhodamine 6G dyes. A detailed analysis of the optical system is presented, and further improvements for the procedure are discussed. 相似文献