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41.
Farahani Nazanin Karami Hojat Farzin Saeed Ehteram Mohammad Kisi Ozgur El Shafie Ahmad 《Water Resources Management》2019,33(14):4879-4893
Water Resources Management - Considering the great importance of flood prediction, flood routing based on Shark Algorithm (SA) and Four-Parameter Nonlinear Muskingum (FPNM) has been proposed in the... 相似文献
42.
Younes Hanifehpour Nazanin Hamnabard Babak Mirtamizdoust Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(3):623-631
Terbium-doped cadmium sulfide nanoparticles with different terbium contents were successfully synthesized via sonochemical route. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, photoelectron X-ray spectroscopy, and UV–Vis diffuse reflectance spectroscopy techniques. The as-prepared nanocatalyst were used for sonocatalytic degradation of Methylene Blue. Among the different amounts of dopant, 8 % Tb-doped CdS showed the highest sonocatalytic activity. The order of inhibitory effect of radical scavengers was 1, 4 Benzoquinone > SO3 2? > CO2 3?> I?. The effects of various parameters such as initial dye concentration, catalyst loading, ultrasonic power, and the presence of radical scavengers were investigated. 相似文献
43.
Nazanin Forouzanmehr Mahmoud Nili-Ahmadabadi Matthias Bönisch 《The Physics of Metals and Metallography》2016,117(6):624-633
Pure Fe was severely deformed by a combination of shaped cold rolling and cold drawing. X-ray diffraction profiles analysis was applied in accordance with the Williamson-Hall (WH) and modified Williamson-Hall (MWH) methods to identify crystallite sizes of the deformed specimens. It was found that some differences exist between the results of WH and MWH procedures using the hkl dependent Young’s modulus or considering the average dislocation contrast factor. The latter method is more accurate and enables the determination of the character of dislocations in plastically deformed Fe. It was shown that by increasing deformation strain, the screw dislocations dominated. The enhancement of hardness occurs in the deformed Fe due to grain refinement, dislocation accumulation and deformation-induced vacancies. 相似文献
44.
Surface friction of fabrics is one of the prominent tactile properties which influence the comfort and application of clothes. In this paper, a new approach is proposed to characterize the surface friction of woven fabrics by presenting a model based on fabric structural parameters. The model coefficients are optimized with the aid of the genetic algorithm, using the experimental friction results obtained from the multi-directional tactile sensing mechanism. The model is developed using the properties of 25 groups of woven fabrics consisting of 5 various weave structures and 5 different weft densities, with similar fibre composition. The statistical analysis of Friction results clarified that the effect of fabric structural parameters such as weave structure and weft density is significant in the confidence range of 95%. The importance of proposing the friction model is that the frictional properties of woven fabrics can be estimated by considering the structural parameters of woven fabrics. This model can be utilized for the forecasting of the friction resistance of various types of woven fabrics without experimental testing procedures. 相似文献
45.
Rama K. Vasudevan Hamidreza Khassaf Ye Cao Shujun Zhang Alexander Tselev Ben Carmichael M. Baris Okatan Stephen Jesse Long‐Qing Chen S. Pamir Alpay Sergei V. Kalinin Nazanin Bassiri‐Gharb 《Advanced functional materials》2016,26(4):478-486
Materials near structural phase transitions find applications in a wide range of devices. Typically, phase transitions are determined macroscopically through measurements of relevant order parameters and related property coefficients. Here, a method for understanding electric field induced phase transitions in ferroelectrically active materials at the nanometer scale via acoustic detection with band‐excitation piezoresponse force microscopy (BE‐PFM) is introduced. Specifically, the field‐induced rhombohedral (R) to tetragonal (T) phase transition in single crystal 0.72PbMg1/3Nb2/3O3‐0.28PbTiO3 (PMN‐PT) is mapped. It is shown that due to sample heterogeneity, some regions are more prone to the R–T transition, and display signatures in the acquired piezoresponse loops, as well as pronounced softening in the elastic modulus (monitored via the resonant frequency and calibrated with models of cantilever dynamics) that occurs just prior to phase switching. Landau–Devonshire thermodynamic theory confirms the stability of the tetragonal phase under applied fields in PMN‐PT, while phase‐field modeling suggests that the transition evolves smoothly in the probed volume of the tip, both in agreement with the BE‐PFM results. These results confirm the validity and utility of utilizing acoustic changes at phase transitions to detect their onset in nanoscale probed volumes, allowing spatial mapping of their onset with unprecedented resolution. 相似文献
46.
In this study, a porous organic triazine‐based polyimide (PPI network) was prepared from 2,4,6‐tris(hydrazino)‐s‐triazine and 3,4,9,10‐perylenetetracarboxylic dianhydride. TGA, Fourier transform infrared spectroscopy, field emission SEM, XRD and a nitrogen sorption study confirmed the PPI network structure. Then, the synthesized PPI network was used to evaluate Ni2+ ion removal from aqueous solution and the effective parameters on adsorption functions of Ni2+ ions such as initial concentration, contact time and pH of the solution in batch adsorption experiments was studied. The results showed that the maximum adsorption capacity (qm) of Ni2+ ions was 36.1 mg g?1 in only 30 min with a pH of 7. The kinetics and adsorption isotherm were identified to be better fitted by the pseudo‐second‐order model and the Langmuir model, respectively. Based on the results, the proposed adsorbent has good potential for removing Ni2+ ions from aqueous solutions. © 2019 Society of Chemical Industry 相似文献
47.
The objective of this research was to conduct an experimental and theoretical investigation into the antioxidant properties of thymol and 2,5,6-trifluorothymol. Calculations based on the density functional theory were performed using the B3LYP exchange-correlation functional and the 6-311G(d,p) standard basis set to determine the carbon-fluorine bond dissociation enthalpy of 2,5,6-trifluorothymol and thymol in the gas phase and in solution in water and in methanol. Computed delta binding dissociation energies and delta ionization potential values of theoretical 2,5,6-trifluorothymol, test of total phenolics, and 1,1-diphenyl-2-picrylhydrazyl assay allowed the authors to conclude that both thymol and 2,5,6-trifluorothymol have a protective antioxidant action. 相似文献
48.
Nazanin Mossahebi 《Journal of Constructional Steel Research》2005,61(3):371-386
An experimental investigation was carried out in an effort to comprehend the behavior of a bridge girder consisting of a steel tube filled with reinforced concrete and made composite with an overlying concrete deck. The experimental investigation also provided information for assessing various erection scenarios using such a system in bridge construction. The investigation consisted of designing and constructing a test specimen and loading it to collapse.A moment curvature analysis was used to predict the ultimate capacity of the system. This approach was able to predict the observed test behavior with good accuracy. The test specimen showed good ductility and maintained its strength up to the end of the test. Results of this investigation demonstrated the potential for using a concrete filled tube as a bridge girder. 相似文献
49.
The deformation of polymers at constant applied stress is one of their major drawbacks, limiting their use in advanced applications. The study of this property using classical techniques requires extensive testing over long periods of time. It is well known that reinforced polymers show improved behavior over time compared to their neat counterparts. In this study, the effect of adding different amounts of graphene nanoplatelets (GNPs) on the time-dependent properties of high-density polyethylene (HDPE) is investigated using short-term creep tests and load/unload recovery tests. The results are discussed in terms of the test profile and the influence of loading history. Viscoplasticity/viscoelasticity analysis is performed using Zapas model and by comparing creep, creep compliance and pure viscoelasticity curves. The results show that the reinforcement of 15 wt% GNP have the most significant effect on the time-dependent behavior, reducing the strain by more than 50%. The creep compliance curves show that nano-reinforced HDPE behaves nonlinearly viscoelastically even at very low stresses. In addition to demonstrating the effect of nano-reinforcement, the discussion of the results concludes that the influence of loading history can be quite significant and should not be neglected in the design and evaluation of material behavior. 相似文献
50.
Nazanin Vafaei Kirk Marat Michael N. A. Eskin Curtis B. Rempel Peter J. H. Jones Martin G. Scanlon 《Journal of the American Oil Chemists' Society》2020,97(2):125-133
Finding a fast, reliable, and reproducible approach for an accurate analysis of complex lipid mixtures of emulsifiers is crucial for the food and beverages, pharmaceuticals, personal care products, cosmetics, and agrochemicals industries. In the current study, a comprehensive qualitative and quantitative nuclear magnetic resonance (NMR) spectroscopy analysis of a high monoester mixture of soybean oil (HMMS) was conducted using 1H, 13C, and 31P NMR of 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane (CTDP) derivatives. The HMMS was produced by enzymatic alcoholysis of soybean oil and 1.2-propanediol in a supercritical CO2 system. Compositional distribution analysis, quantified by aliphatic carbons with 13C NMR, showed that HMMS is composed of more unsaturated fatty acids, comprised of polyunsaturated fatty acids (PUFA) (60 ± 1.1%) and monounsaturated fatty acids (MUFA) (22 ± 0.8%), than saturated fatty acids (18 ± 0.9%). The 31P NMR quantification of HMMS demonstrated that, out of the total amount of monoacylglycerols (MAG), they are composed of 21 ± 2.9% of 2-MAG and 4 ± 0.3% of 1-MAG. Among the three techniques, 31P NMR spectroscopy proved to be a practical methodology with high reproducibility for the precise detection and quantification of partially esterified glycerols and free fatty acids in complex lipid mixtures. 相似文献