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《Food and Bioproducts Processing》2014,92(1):46-53
The performance of industrial cleaning in place (CIP) procedures is critically important for food manufacture. CIP has yet to be optimised for many processes, in part since the mechanisms involved in cleaning are not fully understood. Laboratory tests have an important role in guiding industrial trials, and this paper introduces and compares two experimental techniques developed for studying CIP mechanisms: local phosphorescence detection (LPD), and scanning fluid dynamic gauging (sFDG).To illustrate the comparison, each technique is used to investigate the influence of soil topology on the cleaning of pre-gelatinised starch-based layers from stainless steel (SS 316) substrates by aqueous NaOH solutions at ambient temperature. The roughness of the soil surface is varied by incorporating zinc sulphide particles with different particle size distributions (range 1–80 μm) into the starch suspensions. The soil roughness increased with the use of larger particles, increasing the 3D arithmetic mean roughness (Sa) of the dry layers (range 0.37–3.33 μm). Rough layers were cleaned more readily than those containing small inclusions, with a good correlation between the cleaning rates observed during LPD and FDG measurements. The LPD technique, which is an instrumented CIP test, gives a better indication of the cleaning time, while sFDG measurements provide further insight into the removal mechanisms. 相似文献
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《Ceramics International》2020,46(9):13047-13053
Porous (Ba,Sr)(Co,Fe)O3-δ (BSCF) ceramics with high open porosity and good electrical conductivity was fabricated using Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), which shows a high mixed ionic-electronic conductivity. In general, during the fabrication of porous ceramics by the sacrificial template method using pore former particles, closed pores are easily formed unless sufficient pore former particles are added. In this study, we have devised a method using the gelatinization-retrogradation phenomena of starch for producing a porous body with an excellent percolated pore network structure. By dispersing BSCF and starch in an aqueous slurry (0–50% by weight) and heating, gelatinization of the starch occurred and the starch particles adhered to each other. Furthermore, in order to retain the percolated structure, the water solvent was removed by freeze-drying without heating to obtain a dried green body. The sintering behavior of the porous BSCF bodies prepared under various conditions was characterized by microstructural observations and relative density measurements. By optimizing the process conditions of the gelatinization and retrogradation, a porous body having an open porosity of 48.3%, and with 99% of the total pores open, was obtained. The matrix was also well connected and showed a sufficiently high conductivity which was similar to the porous bodies made by the traditional sacrificial template method. 相似文献
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Zhongwei Tan Xingguo Xu Yu Wan Chengjun Kang Zhaoqiang Zhang Zhenxia Zhao Fang Shen Kungang Chai Hongbing Ji 《中国化学工程学报》2022,49(9):150-160
Adsorptive recovery of valuable components from industrial wastewater is highly desirable for avoiding resource wastage but remains a challenge. Herein, we develop an efficient continuous adsorption process for recovering aromatic compounds in wastewater from styrene monomer and propylene oxide coproduction(SMPO) plant. Based on our insight into the potential of bio-based porous materials for adsorption application, starch-graft-polystyrene(SPS) and aryl-modified β-cyclodextrin(ACD) were prepare... 相似文献
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The rheological properties of acid skim milk gels, prepared from milk with added potato starch and pH adjusted (pH 6.5–7.1) prior to heat treatment and acidification, were investigated. The storage modulus, G′, of the final acid gels was increased by heating the milk at higher pH and further increased by adding starch. The effect of pH at heating and addition of starch appeared to be additive and independent of each other up to a starch addition level of 1%. Above this starch level, the pH at heating had a lesser effect. This may have been due to the increased viscosity of the aqueous phase as a result of starch gelatinization or to direct contributions of the starch to the gel network structure. Confocal microscopy showed that milk proteins developed fewer but broader protein clusters at higher pH than at lower pH. Starch addition resulted in an increased density of the protein network. 相似文献
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Supervised Multivariate Analysis of Hyper-spectral NIR Images to Evaluate the Starch Index of Apples 总被引:4,自引:0,他引:4
Paolo Menesatti Angelo Zanella Stefano D’Andrea Corrado Costa Graziella Paglia Federico Pallottino 《Food and Bioprocess Technology》2009,2(3):308-314
Fruit maturity indexes are crucial in harvest time determination and commercial context. The harvest time of apples, matching
the desired commercial characteristics, is assessed through starch–iodine test in practice. Fruit halves are dipped into iodine
solution and patterns are visually evaluated by experts comparing them to reference charts. Aim of the work was to study the
relationships of near infrared (NIR) spectral images (1,000–1,700 nm), starch/starch-free patterns visually assessed and RGB
color images. Spectral images of 88 Golden Delicious Klon B apples were sampled at seven different maturity stages. Partial
least-squares discriminant analysis (PLSDA) technique was used on hyper-spectral NIR images to classify single pixels using
its NIR reflectance spectrum. The response variable (i.e. the classification for each pixel) was identified through the matching
of single pixel obtained with the color images, segmented in two classes (starch and starch-free), and the NIR hyper-spectral
matrix. Mean hyper-spectral classification obtained through PLSDA modeling on individual apple correctly classified 80.81%
of the total pixels, while the unique model, i.e. a single model including all the fruits, resulted in 66.33%. In the latter
case, the relationship with the RGB classification showed high values (Pearson correlation coefficient r = 0.95). The present work shows the feasibility of NIR imaging spectroscopy as a tool for apple fruit maturity determination,
avoiding expert’s subjective interpretation by traditional starch index assignments. 相似文献