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11.
MICHAEL KOZEMPEL NEIL GOLDBERG J. ANDRA DICKENS KIM D. INGRAM JAMES C. CRAIG 《Journal of food process engineering》2003,26(5):447-468
The Vacuum/Steam/Vacuum surface intervention pilot plant processor was scaled up to a mobile unit that can be transported to close proximity of chicken processing plants. After several modifications to the mandrel that supports the broiler carcass in the treatment chamber to minimize mechanical damage, the unit was capable of 1.1 log cfu/mL kill of inoculated Listeria innocua and 1.4 log cfu/mL kill of inoculated E. coli K‐12. Field tests achieved 1.4 log kill of E. coli and 1.2 log kill of Campylobacter on freshly processed chicken using 3 cycles and 138C saturated steam. But, there was extensive mechanical damage. the mandrel was modified in the Eastern Regional Research Center pilot plant to eliminate the mechanical damage. With mechanical damage eliminated, the bacteria kill was 1.1–1.5 log of inoculated E. coli K‐12 with a total process time of 1.1 s. 相似文献
12.
YOUNG-IN KWON EMMANOUIL APOSTOLIDIS YOUNG-CHEUL KIM KALIDAS SHETTY 《Journal of Food Biochemistry》2009,33(5):649-673
Tissue culture-generated shoot-based clonal lines of oregano that have a short and long life span during in vitro culture were investigated to determine the role of proline-linked pentose phosphate pathway in modulating phenolic response following ultraviolet (UV) exposure. This novel reductant cycling pathway for energy and oxidative pentose phosphate pathway (PPP) is more efficient in long life span O-17 clonal line in response to UV and this supported antioxidant response. UV treatment stimulated rosmarinic acid and associated antioxidant enzyme response in O-17 clonal line compared with short life span O-3 clonal line. Additionally, O-17 clonal line had higher glucose-6-phosphate dehydrogenase and guaicol peroxidase activity in response to UV exposure compared with O-3 clonal line, indicating stimulation of anabolic pathway supporting PPP during UV treatment. The stimulation of proline dehydrogenase (PDH) activity in O-17 clonal line in response to UV indicated a switch to PDH-linked energy pathway via proline oxidation.
This oregano clonal model of ultraviolet (UV)-induced oxidative stress management has implications for designing dietary phytochemicals to manage oxidation-linked disease in humans. Further, the correlation between UV-linked inducibility of phenolic-linked antioxidant enzyme response through proline-linked pentose phosphate pathway and life span of in vitro shoot cultures of specific oregano clonal lines can be a good model for aging studies. The metabolic response link to aging and protective phytochemicals can be investigated in oregano tissue cultures, and phenolic extracts from various responding clonal lines could be explored in other eukaryotic aging models. 相似文献
PRACTICAL APPLICATIONS
This oregano clonal model of ultraviolet (UV)-induced oxidative stress management has implications for designing dietary phytochemicals to manage oxidation-linked disease in humans. Further, the correlation between UV-linked inducibility of phenolic-linked antioxidant enzyme response through proline-linked pentose phosphate pathway and life span of in vitro shoot cultures of specific oregano clonal lines can be a good model for aging studies. The metabolic response link to aging and protective phytochemicals can be investigated in oregano tissue cultures, and phenolic extracts from various responding clonal lines could be explored in other eukaryotic aging models. 相似文献
13.
为了探讨平贝母多糖对D-半乳糖诱导衰老模型小鼠的体内抗氧化作用,采用颈背皮下注射D-半乳糖(500mg/(kg ·d))建立亚急性衰老小鼠模型,通过对各组小鼠一般体征、脏器指数、血清或肝组织抗氧化酶活性及脑组织单胺氧化酶(MAO)活力的比较分析,全面评价平贝母多糖FUP-1的抗氧化衰老作用。结果表明:与模型组相比平贝母多糖FUP-1能显著降低D-半乳糖诱导衰老小鼠肝脏组织中丙二醛(MDA)含量(P<0.05),提高肝组织中总抗氧化能力(T-AOC)、显著提高肝组织中谷胱甘肽过氧化物酶(GSH-Px)活性和血清超氧化物歧化酶(SOD)活性(P<0.05),同时降低脑组织中MAO活力。提示平贝母多糖FUP-1具有一定的延缓衰老作用,其作用可能与其提高抗氧化酶活性和抗脂质过氧化有关。 相似文献
14.
Gram Negative Bacteria Inhibition by Lactic Acid Culture and Food Preservatives on Catfish Fillets during Refrigerated Storage 总被引:2,自引:0,他引:2
Treating catfish fillets with sodium acetate (SA) and/or potassium sorbate (PS), with or without lactic culture (Lactococcus lactic spp. cremoris ATCC 19257 grown in 20% milk solids) was studied at 4°C. Gram negative bacterial (CVT) counts on crystal violet tetrazolium chloride agar, pH, and sensory evaluation of fillets were assessed over time. Treatment with the combination of 0.50% SA, 0.25% PS with 2.50% lactic acid culture (LC) and, also, 0.50 to 1.00% SA alone completely inhibited growth for 6 days at 4°C. After 12 days, counts with this treatment and the 1.00% SA increased ~1.3 and 1.2 log cycles, respectively. The antimicrobial effects did not appear to be due to pH values. The combination of 0.50% SA and 0.25% PS with 2.50% LC, or 1.00% SA, alone, improved catfish odor and appearance during 13 days storage. 相似文献
15.
MIE SOON LEE-KIM EUN SUN HWANG KYUNG HYUN KIM 《Journal of Food Processing and Preservation》1997,21(6):485-494
The inhibitory effect of 4-hexylresorcinol (HR), ascorbic acid (AA), citric acid (CA), and bisulfites on polyphenol oxidase (PPO) of burdock roots was studied. HR was an effective inhibitor at low concentrations used in this study for crude PPO from root slices. A binary mixture of HR and AA at 1.0% concentration for 5 min achieved more than 90% inhibition of crude PPO. AA also showed high antibrowning activity for the purified PPO comparable to that of bisulfites, whereas its activity was much lower than that of HR in the crude extract. The inhibitory effect of the combined use of inhibitors was overall in the decreasing order of HR+AA, HR+CA and AA+CA, irrespective of the crude PPO or the purified PPO from burdock slices. 相似文献
16.
A serial filtration system was developed for separating immunoglobulin from egg yolk (IgY). Egg yolk was diluted 10 times with water, adjusted to pH 5.0, frozen, then thawed. The diluted yolk was diafiltered through a hard filter paper at 4-6°C to produce a clear water-soluble fraction (WSF). The WSF was then delipidated by filtering through a hydrophobic membrane filter. Ultrafiltration of delipidated WSF at pH 9.0, at 4-6°C, in the presence of 1.5M NaCl resulted in electrophoretically pure (>90%) IgY with a recovery of about 92%. Advantages of this method are the use of only a few mild chemicals and the potential of developing a continuous process. 相似文献
17.
Bacillus subtilis JM‐3 was isolated from anchovy sauce naturally fermented in an underground cellar at 15 ± 3C for 3 years. The activity of the B. subtilis protease was highest in the 40–60% ammonium sulfate fraction. The yield of the purified protease was 5.3%, and its purification ratio was 35.6 folds. The molecular weight of the B. subtilis protease was 17.1 kDa, and its Km and Vmaxvalues were 1.75 μg/mL and 318 μM 1/min, respectively. The optimal temperature for protease activity was 60C, but optimal stability temperature was 30C. The optimal pH for protease activity and stability was 5.5. Therefore, the B. subtilis JM‐3 protease was classified as an acid protease. The relative activities of the B. subtilis JM‐3 protease were 69, 21 and 1.3% at 10, 20 and 30% NaCl concentrations, respectively. The best substrate for the B. subtilis JM‐3 protease was benzyloxycarbonyl‐glycine‐p‐nitrophenyl ester followed by bovine serum albumin. p‐Toluene‐sulfonyl‐L‐lysine chloromethylketone was the strongest inhibitor followed by soybean trypsin inhibitor, but N‐ethylmaleimide did not inhibit this enzyme. The B. subtilis JM‐3 protease was therefore presumed to be a trypsin‐like serine protease. 相似文献
18.
19.
USE OF OZONE TO INACTIVATE MICROORGANISMS ON LETTUCE 总被引:6,自引:0,他引:6
When ozone (1.3 mM) was bubbled for 3 min in a mixture of shredded lettuce and water, counts ofmesophilic andpsychrotrophic bacteria decreased 1.4 and 1.8 log10 cfu/g, respectively. Counts of these microorganisms on lettuce, from a different batch, decreased 3.9 and 4.6 log, respectively, during 5 min of ozone treatment. Shredded lettuce was treated with gaseous ozone, or mixed with aqueous solution of ozone (1:20 w/w) with or without bubbles. For effective delivery of ozone, stirring (low and high speed), sonication or stomaching was applied during the ozonation. Washing the lettuce with water only decreased total count on shredded lettuce by 0.74–1.0 log cfu/g. When lettuce in a treatment chamber was flushed with gaseous ozone, the total count decreased 0.85 log cfu/g, but when vacuum was applied before the ozone flush, the total count decreased 0.96 log cfu/g. Bubbling ozone in water-lettuce mixture while sonicating, high-speed stirring, or before stomaching inactivated 1.4, 1.9 and 1.9 log cfu/g, respectively. In conclusion, bubbling gaseous ozone in water is the most effective ozonation method. Efficient ozone delivery to microorganisms on lettuce requires a combination of ozone bubbling and high-speed stir. 相似文献
20.
Masazumi OKIDO Ryoichi ICHINO Seong-Jong KIM Seok-Ki JANG 《中国有色金属学会会刊》2009,19(4):892-897
The chemical conversion coating was formed on Mg alloy for low cost and harmlessness in environment by using the colloidal silica as the main component. The film formed at 298 K was thick, which was thought to be the combination of Si and O. In salt spray test, the ratio of black rust on the specimen that did not conducted chemical conversion treatment was five times or more than those of the chemical conversion treated specimen. The film of chemical conversion coating produced by alkali treatment process was thinner than the specimen produced in basic chemical conversion treatment solution. 相似文献