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11.
KEITH W. GATES AMANDA H. PARKER DIANA L. BAUER YAO-WEN HUANG 《Journal of food science》1993,58(2):314-317
We investigated pasteurization and storage of blue crabmeat in steel cans, aluminum cans, plastic cans, nonbarrier pouches, and barrier pouches. Fresh meat was packed in copolymer polyethylene/polypro-pylene cups, Saran® over-wrapped or vacuum skin packaged polystyrene trays, and nonbarrier pouches. Meat pasteurized in plastic and aluminum cans had better sensory and microbiological quality and longer shelf life than meat packed in steel cans. Oxygen-barrier pouches had the lowest quality and shortest shelf life. Nonbarrier pouches had product with quality similar to meat in steel cans, but with an extended shelf life. No packaging materials improved the microbiological shelf life of freshly cooked meat. Vacuum skin packaging resulted in improved sensory qualities of freshly cooked and picked meat. 相似文献
12.
Crosslinking modification can effectively improve the water resistance of soy protein isolate (SPI) adhesive, but it often depends on petroleum-based reagents, violating the concept of green environmental protection. Here, inspired by the breaking and recombination of the disulfide bond in the perm process, a high-performance wood adhesive is prepared by incorporation of SPI (modified by sodium sulfite to cleave the disulfide bonds of protein chains) and feather keratin (FK, extracted from waste chicken feathers by breaking the disulfide bond) without using any other crosslinkers. The crosslinking reaction occurs by disulfide bonds derived from the sulfhydryl group of FK and SPI. Thus the wet shear strength of the SPI/FK-20 adhesive is improved from 0.57 to 1.18 MPa, an increment of 107%. This study provides a green strategy to prepare high-performance protein-based adhesive from the waste products-chicken feathers, which will contribute to the development of the environmentally friendly wood adhesive industry. 相似文献
13.
14.
D. L. Purcell B. T. McClure J. McDonald Hemendra N. Basu 《Journal of the American Oil Chemists' Society》1996,73(3):381-388
An evaluation of the exhaust emissions from a compression ignition engine for fuels composed of 100 and 30% methyl esters
of soy oil (SME) is described. These fuels were compared with a low-sulfur, petroleum #2 diesel fuel in a Caterpillar 3304,
prechamber, 75 kW diesel engine, operated over heavy- and light-duty transient test cycles developed by the United States
Bureau of Mines. More than 60 h of testing was performed on each fuel. The objective was to determine the influence of the
fuels upon diesel particulate matter (DPM) and gaseous emissions. The effect of a modern diesel oxidation catalyst (DOC) also
was determined in an effort to minimize emissions. Neat SME produced a higher volatile fraction of the DPM, but much less
carbon soot fraction, leading to overall DPM reductions of 23 to 30% for the light- and heavy-duty transients. The DOC further
reduced the volatile fraction and the total DPM. The SME fuel reduced gaseous emissions of CO by 23% and hydrocarbons by over
30% without increasing NOx. The DOC further reduced CO and hydrocarbon levels. Mutagenicity of the SME exhaust was low. Results indicate that SME fuel,
used with a proper DOC, may be a feasible emission reduction technology for underground mines.
References to specific products do not imply endorsement by the U.S. Bureau of Mines, a now defunct agency. 相似文献
15.
Flaking and extrusion as mechanical treatments for enzyme-assisted aqueous extraction of oil from soybeans 总被引:6,自引:7,他引:6
B. P. Lamsal P. A. Murphy L. A. Johnson 《Journal of the American Oil Chemists' Society》2006,83(11):973-979
Flaking and extruding dehulled soybeans were evaluated as a means of enhancing oil extraction efficiency during enzyme-assisted
aqueous processing of soybeans. Cellulase, protease, and their combination were evaluated for effectiveness in achieving high
oil extraction recovery from extruded flakes. Aqueous extraction of extruded full-fat soy flakes gave 68% recovery of the
total available oil without using enzymes. A 0.5% wt/wt protease treatment after flaking and extruding dehulled soybeans increased
oil extraction recovery to 88% of the total available oil. Flaking and extruding enhanced protease hydrolysis of proteins
freeing more oil. Treating extruded flakes with cellulase, however, did not enhance oil extraction either alone or in combination
with protease. Discrepancies in oil extraction recoveries were encountered when merely considering crude free fat because
some oil became bound to denatured protein during extrusion and/or sample drying. Bound fat was unavailable for determination
by using the hexane extraction method, but was accounted for by using the acid hydrolysis method for total oil determination.
Oil extraction recovery from extruded soybean flakes was affected by oil determination methods, which was not the case for
unextruded full-fat soy flour. 相似文献
16.
The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale.
The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment
and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding
of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour.
A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove
all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced.
Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids)
from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality
of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation
to separate miscella from meal. 相似文献
17.
测定不同水解度(DH)时酱渣多肽及其美拉德反应产物(MRPS)的抗氧化性,结果表明:随反应物浓度增加,两者抗氧化性增强;两者的DPPH.清除率与DH并非呈线性关系;DH〈14.2%时,两者的.OH清除率随DH的升高而降低;两者的还原力变化趋势不同,DH〉12.2%时,酱渣多肽还原力随DH增大逐渐减少,DH〉8.2%时,MRPS的还原力随DH提高逐渐增大.与某些多肽类物质和MRPS相比,酱渣多肽及其MRPS具有较高的抗氧化性和很好的应用价值. 相似文献
18.
沈涛 《四川烹饪高等专科学校学报》2010,(3):12-13
本文将四川名菜水煮牛肉与麻辣火锅从味型、技术、原料等角度进行了对比分析,认为“麻辣火锅的起源地在自贡”一说更具说服力。 相似文献
19.
20.
采用差示扫描量热法(DSC)研究了成膜基质比例、增塑剂丙三醇体积分数和pH值对大豆分离蛋白(SPI)/壳聚糖(CS)共混膜热力学性能的影响。结果表明:共混膜较相同条件下SPI和CS单纯膜的结构更加稳定,成膜基质比例SPI∶CS=1∶1时共混膜交联度最高,热稳定性最好;增塑剂丙三醇体积分数的提高可降低共混膜放热峰的高度,增加放热峰的宽度,但是玻璃化转化温度和熔融温度随之降低;当pH值在1~3时,共混膜的玻璃化转化温度、熔融温度和结晶度值均较低,pH值在4~6时,各值升高,共混膜的热稳定性较好。 相似文献