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141.
Ohmic cooking of ground beef: Effects on quality 总被引:1,自引:0,他引:1
Conventional cooking tends to be slow and the surface of the food always receives a much more severe heating treatment than the rest of the food. Ohmic heating has the potential to be much faster and produces even more cooking. In this work cylindrical ground beef samples having different initial fat contents (2%, 9% and 15%) were cooked ohmically (20, 30 and 40 V/cm) and conventionally. Ohmic cooking was faster than the conventional cooking (p < 0.05). Ohmically cooked samples were firmer than those conventionally cooked but yield and fat retention was similar. However, the reduction in volume during cooking was significantly smaller from 5.36% to 6.97% in ohmic cooking than the conventional system which was measured from 26.01 to 31.59. The voltage gradient applied during ohmic cooking was not related to the quality of the cooked meat. These results show that ohmic cooking could be a fast-alternative method for meat products. 相似文献
142.
A new decision-based algorithm has been proposed for the restoration of digital images which are highly contaminated by the saturated impulse noise (i.e., salt-and-pepper noise). The proposed denoising algorithm performs filtering operation only to the corrupted pixels in the image, keeping uncorrupted pixels intact. The present study has used a coupled window scheme for the removal of high density noise. It has used sliding window of increasing dimension, centered at any pixel and replaced the noisy pixels consecutively by the median value of the window. However, if the entire pixels in the window are noisy, then the dimension of sliding window is increased in order to obtain the noise-free pixels for median calculation. Consequently, this algorithm has been found to be able to remove the high density salt-and-pepper noise and also preserved the fine details of the four images, Lena, Elaine, Rhythm, and Sunny, used as test images in this study (The latter two real-life images have been acquired using Sony: Steady Shot DSC- S3000). Experimentally, it has been found that the proposed algorithm yields better peak signal-to-noise ratio, image enhancement factor, structural similarity index measure and image quality index, compared with the other state-of-art median-based filters viz. standard median filter, adaptive median filter, progressive switched median filter, modified decision-based algorithm and modified decision-based unsymmetric trimmed median filter. 相似文献
143.
144.
In this study, two shared storage assignment policies are compared in an Automated Storage/Retrieval System (AS/RS) by using computer simulation. The AS/RS is assumed to operate under a continuous review, order quantity, reorder point inventory policy. The average travel time of the AS/R machine for storing and retrieving products is used as the main performance measure. Sensitivity of the system to product variety, inventory replenishment lead time, and demand rate is investigated, as well as the effects of the inventory policy and the product classification technique used. Our main conclusion is that the turnover-based policy, in general, outperforms the duration of stay-based policy. However, the' difference between the performance of the two policies becomes insignificant under certain conditions. 相似文献
145.
The long-term chemical evolution in waste deposits and the release of toxic metals was investigated. The degradation of organic matter and hence the potential efflux of heavy metals in a long-term perspective was studied by defining some scenarios for waste deposits containing organic compounds, different longevity and functions of covers and different water and air intrusion rates. The scenarios were based on various transport processes as well as different landfill constructions. The rates of influx of oxygen into both saturated and partially saturated landfills have been estimated. Each scenario takes the form of a mathematical model. The starting point for all the studied cases is the humic phase, i.e. the phase after the methane production has stopped. Based on the different cases studied, it appeared that landfills where the waste is below the water table could have advantages over the other cases. Recognizing that this option is not accepted in most countries we, nevertheless, suggested it should be reevaluated. The main conclusion is that the degradation of humic matter and hence the release of toxic metals can be substantially decreased if potential build-up of hydraulic gradients are avoided and if the landfill is located below the water surface. A conceivable alternative construction would be to place it in a depression--either natural or artificial--and to construct it so that under normal conditions it would always be water-saturated. 相似文献
146.
Novel composite polymer electrolyte membranes based on poly(vinyl phosphonic acid) and poly (5‐(methacrylamido)tetrazole)
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Deniz Sinirlioglu Sevim Ünügür Çelik Ali Ekrem Muftuoglu Ayhan Bozkurt 《Polymer Engineering and Science》2015,55(2):260-269
Heterocyclic molecules are generally used in the proton conducting membranes as dopant or polymer side group due to their high proton transfer ability. Composite proton conducting membranes based on poly(vinylphosphonic acid) (PVPA) and poly(5‐(methacrylamido)tetrazole) (PMTet) were produced. The homopolymers, prepared from their corresponding monomers, were blended at several mol ratios to obtain the polymer electrolyte membranes. All samples were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differantial scanning calorimetry (DSC), cyclic voltammetry (CV), and impedance analysis. Besides, the morphology of the membranes was studied by X‐ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). FTIR spectra confirmed the formation of hydrogen bonding network between PVPA and PMTet units. TGA showed that the polymer electrolyte membranes were thermally stable up to ~210°C. CV curves demonstrated the oxidative stability of the samples in 3 V region. In anhydrous conditions, the maximum proton conductivity was determined as 0.06 Scm?1 at 150°C for PMTetP(VPA)4. POLYM. ENG. SCI., 55:260–269, 2015. © 2014 Society of Plastics Engineers 相似文献
147.
Fossil fuels cover most of the energy demand in the world, and this creates significant social, economic and environmental problems. Many countries have taken measures to increase the share of renewable energy sources (RES), especially in electricity generation, and the review of literature shows that the success of a country in RES diffusion depends on a comprehensive renewable energy policy which combines political commitment with stable and long-term support measures that stimulate technological innovation. As the largest economy in the world, EU has also taken steps to increase RES usage in electricity generation in member states. Similar to other developing countries, Turkey is learning lessons from EU experiences regarding RES policies, and Turkey is also reforming its legal framework in line with acquis communautaire as a candidate country. As a result, EU has a multiway impact on Turkey's renewable energy policy. An overview of Turkey's renewable energy policy showed that EU has significantly contributed to Turkey in shaping its renewable energy policy, and Turkey should increase cooperation with EU in order to utilize its renewable energy potential. 相似文献
148.
Mustafa Tahsin Yilmaz Perihan Kubra Akman Fatih Bozkurt Salih Karasu 《International Journal of Food Science & Technology》2021,56(11):6011-6024
In this study, a simple and facile method was used to fabricate carvacrol-loaded zein nanoparticles (CLZNPs), and CLZNPs were coated with different concentrations (0.25, 0.5 and 1 mg mL−1) of polydopamine (PDA) to fabricate CLZPNPs. Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses showed that CLNPs and CLZPNPs possessed spherical shapes with smooth surfaces in the sizes of 562 and 725 nm and were highly stable possessing high encapsulation efficiency (81.3%). The antioxidant activity of CLZPNPs (ranging from 70.97% to 89.84%) was higher than that (51.42%) of CLZNPs. PDA had a significant effect to increase the antioxidant activity of the CLZNPs. The thermal stability of the particles was influenced by a temperature change from 30 °C to 70 °C. While 1 CLZPNP sample possessed the highest retention rate of carvacrol, the uncoated CLZNPs had the lowest retention value at all temperatures. The antibacterial effect of CLZNPs could be remarkably increased by their coating with PDA at different concentrations (0.25, 0.5 and 1 mg mL−1), reaching the level of 100% inhibition of Salmonella typhimurium, Pseudomonas aeruginosa and Staphylococcus aureus. As a result, coating the carvacrol-loaded nanoparticles (CLZNPs) with PDA enabled us to fabricate highly stable CLZPNPs possessing improved stability and bioactivity. The results of this study suggest that the fabricated nanoformulation would find an application in food packaging technology to increase the storage stability of the products and control various foodborne bacterial pathogens. 相似文献
149.
Bora Timurkutluk Tolga Altan Serkan Toros Omer Genc Selahattin Celik Habip Gokay Korkmaz 《International Journal of Hydrogen Energy》2021,46(24):13298-13317
In this study, a typical solid oxide fuel cell (SOFC) electrode microstructure is numerically optimized in terms of the volume fraction of the catalyst, electrolyte and pore phases via a novel tool based on Dream.3D for the synthetic microstructure reconstruction and COMSOL Multiphysics® Modeling for visualizing and computing three/triple phase boundaries (TPBs). First, the properties of the representative volume element are studied by a parameter independence analysis based on the average particle size. The results indicate that the size of the representative volume element should be at least 10 times greater than the largest average particle size in the microstructure, while the number of mesh elements should be selected such that the smallest average particle size in the system is divided into at least 5. The method is then validated with the available studies in the literature and seems to agree well. Therefore, numerical reconstruction of SOFC electrodes by the proposed method is found to be a very useful tool in the viewpoints of accuracy, flexibility and cost. Finally, SOFC electrode microstructures having the same particle size distribution of an average particle size of 0.5 μm for each phase but with various phase volume fractions are generated and the resultant TPBs are computed similarly. It is found out that the volume fraction of each phase should be close to each other as much as possible to maximize the active TPB density and among the cases considered, the highest active TPB density of 9.53 μm/μm3 is achieved for an SOFC electrode including 35 vol% catalyst, 35 vol% electrolyte and 30 vol% porosity. The active TPB density is also found to be around 93% of the total TPB density. 相似文献
150.
The anhydrous electrolytes have become an important part of supercapacitors, which provide temperature-tolerant applications in various electronic devices. This work reports on the fabrication of a wide-temperature-range supercapacitor using 3-amino-1H-1,2,4-triazole (Atri)/1,4-butanediol diglycidyl ether (BG) and imidazole (Imi)/BG–based electrolytes in active carbon-based electrodes. The triazole-terminated BG (BG(Atri)2) and Imi-terminated BG (BG(Imi)2) were initially synthesized, and then anhydrous electrolytes were produced by doping BG(Atri)2 and BG(Imi)2 with phosphoric acid (H3PO4) and ionic liquid (IL) at different molar fractions. The supercapacitors constructed with the anhydrous BG(Atri)2/H3PO4/0.1IL and BG(Imi)2/H3PO4/0.1IL electrolytes provided maximum specific capacitances (Cs) of 114 and 191 F g−1 at 1 A g−1, respectively. The corresponding electrolytes yielded the highest energy densities of 15.8 and 26.7 Wh kg−1 at the power densities of 1150 and 1225 W kg−1, respectively. The Imi-terminated electrolyte-based supercapacitor indicated superior performance and efficiency even after 2300 charge-discharge cycles by holding 20% of its original capacitance. The temperature dependence of the supercapacitors' capacitances was studied, and they increased from 191 to 266 F g−1 for BG(Imi)2/H3PO4/0.1IL and from 114 to 148 F g−1 for BG(Tri)2/H3PO4/0.1IL as the temperature increased from 25°C to 75°C. 相似文献