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581.
Julie M. Rieland Saeid Nikafshar Zeyuan Hu Mojgan Nejad Brian J. Love 《大分子材料与工程》2023,308(12):2300145
Ionic liquids (ILs) are effective solvents for biomass. Refined cellulose is commonly used; however, recent interest has grown to consider woody and herbaceous biomass and industrial crop residues like fruit peels. Here, the authors report results on the dissolution and shaping of cotton and coffee fruit (cascara) in 1,8-diazabicyclo[5.4.0]undec-7-inium acetate ([DBUH][OAc]). Cascara is a high-volume, low-value crop residue that poses an environmental and economic burden in producer countries leading to a high-value proposition if recoverable. Fruit/ionic liquid solutions (0–15% w/w dissolved at 60 °C) were characterized with respect to biomass concentration and shaped into fibers and films coagulated in DI water and methanol. Rheology was assessed using parallel plate rheometry. Cotton/IL mixtures formed better fibers compared to cascara-based solutions, which required 2.6× more biomass in solution for viable fiber formation. At 10% loading, fibers could be produced from untreated coffee fruit with diameters ranging from 18–100 microns. Coffee fruit residues and their precipitated films show that both cellulose and lignin dissolve in pure [DBUH][OAc]. Chemical characterization of cascara and cascara films demonstrates the conveyance of high concentrations of lignin and extracts that result in weaker mechanical properties. Further purification of cascara is required for effective use in structural applications. 相似文献
582.
Voradon Voraruth Siripon Anantawaraskul Saeid Mehdiabadi João B. P. Soares 《加拿大化工杂志》2023,101(9):5420-5440
Crystallization elution fractionation (CEF) is the newest crystallization-based technique for estimating the chemical composition distribution of ethylene/1-olefin copolymers. Understanding the separation mechanism of CEF for ethylene/propylene copolymers over their full compositional range is challenging because the crystallizabilities of the copolymer chains depend on the longest ethylene sequence and on longest isotactic propylene sequence. We developed a mathematical model to describe the CEF mechanism for ethylene/propylene copolymers over the entire compositional range using population balances for the crystallization and dissolution stages. The joint distribution of longest ethylene and isotactic propylene sequences determines how the copolymer populations crystallize and dissolve. The model was validated with experimental CEF profiles of ethylene/propylene copolymers varying from pure ethylene to propylene homopolymers. 相似文献
583.
Soleiman Hosseinpour Shahin RafieeSeyed Saeid Mohtasebi Mortaza Aghbashlo 《Journal of food engineering》2013
The effects of drying temperature and drying medium velocity on color change kinetics of shrimp viz. lightness (L∗), redness (a∗), yellowness (b∗), total color difference (ΔE), chroma (CH), hue angle (H°), and browning index (BI) were on-lineally investigated. Drying experiments were carried out on dryer equipped with computer vision systems using hot air drying (HAD) temperatures of 50–90 °C and superheated steam drying (SSD) temperatures of 110–120 °C at drying medium velocities of 1–2 m/s. Zero-, first-order, and fractional conversion models were utilized to describe the color changes of shrimps and the fractional conversion model successfully tracked the experimental data. The results showed that the color parameters were significantly influenced by the studied parameters. Lightness of the samples decreased, while other color parameters increased as drying proceeded. Generally, increasing drying medium temperature decreased L∗ and H°, whereas increased other color parameters. The color characteristic of the SSD finished products were acceptable than the HAD processed samples. Finally, dimensionless moisture content of shrimps during drying was accurately correlated to the color parameters and drying time using a quadratic regression model. Moisture ratio had strong relationship with the lightness change compared with the redness and yellowness variations. 相似文献
584.
Neural Computing and Applications - Using a reliable predictive model is important for modeling, controlling, and optimization of the isomerization process. This process has a significant impact on... 相似文献