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11.
12.
To determine effects of very low levels of linolenic acid on frying stabilities of soybean oils, tests were conducted with
2% (low) linolenic acid soybean oil (LLSBO) and 0.8% (ultra-low) linolenic acid soybean oil (ULLSBO) in comparison with cottonseed
oil (CSO). Potato chips were fried in the oils for a total of 25 h of oil use. No significant differences were found for either
total polar compounds or FFA between samples of LLSBO and ULLSBO; however, CSO had significantly higher percentage of polar
compounds and FFA than the soybean oils at all sampling times. Flavor evaluations of fresh and aged (1, 3, 5, and 7 wk at
25°C) potato chips showed some differences between potato chips fried in different oil types. Sensory panel judges reported
that potato chips fried in ULLSBO and aged for 3 or 7 wk at 25°C had significantly lower intensities of fishy flavor than
did potato chips fried in LLSBO with the same conditions. Potato chips fried in ULLSBO that had been used for 5 h and then
aged 7 wk at 25°C had significantly better quality than did potato chips fried 5 h in LLSBO and aged under the same conditions.
Hexanal was significantly higher in the 5-h LLSBO sample than in potato chips fried 5 h in ULLSBO. The decrease in linolenic
acid from 2 to 0.8% in the oils improved flavor quality and oxidative stability of some of the potato chip samples. 相似文献
13.
Charles E. Carraher Jr. Theodore S. Sabir Michael R. Roner Kimberely Shahi Robert E. Bleicher Joanne L. Roehr Kelly D. Bassett 《Journal of Inorganic and Organometallic Polymers and Materials》2006,16(3):249-257
Organotin polyamine ethers containing acyclovir in their backbone were synthesized in moderate to high yield employing the aqueous interfacial polycondensation system. The products are high molecular weight polymers. Infrared spectroscopy of the products shows new bands characteristic of the formation of Sn–N and Sn–O bonds consistent with the proposed structure. MALDI-TOF MS below 2000 Da shows the presence of organotin and acyclovir units containing these two moieties. The products show moderate inhibition of a number of cancer cell lines and exhibit the ability to inhibit a number of viruses, particularly the herpes simplex virus-1 and varicella zoster virus that are responsible for herpes, chicken pox and shingles. 相似文献
14.
K.?WarnerEmail author J.?A.?Laszlo 《Journal of the American Oil Chemists' Society》2005,82(9):647-652
To determine antioxidative effects of ferulic acid and esterified ferulic acids, these compounds were added to soybean oils
(SBO), which were evaluated for oxidative stability and frying stability. Additives included feruloylated MAG and DAG (FMG/FDG),
ferulic acid, ethyl ferulate, and TBHQ. After frying tests with potato chips, oils were analyzed for retention of additives
and polar compounds. Chips were evaluated for hexanal and rancid odor. After 15 h frying, 71% of FMG/FDG was retained, whereas
55% of ethyl ferulate was retained. TBHQ and ferulic acid levels were 6% and <1%, respectively. Frying oils with ethyl ferulate
or TBHQ produced significantly less polar compounds than SBO with no additives. Chips fried in SBO with TBHQ or ferulic acid
had significantly lower amounts of hexanal and significantly less rancid odor after 8 d at 60°C than other samples. Oils were
also aged at 60°C, and stability was analyzed by PV, hexanal, and rancid odor. Oils with TBHQ or FMG/FDG had significantly
less peroxides and hexanal, and a lower rancid odor intensity than the control. FMG/FDG inhibited deterioration at 60°C, whereas
ethyl ferulate inhibited the formation of polar compounds in frying oil. Ferulic acid acted as an antioxidant in aged fried
food. TBHQ inhibited oil degradation at both temperatures.
Presented at the 94th AOCS Meeting & Expo, Kansas City, MO, May 4–7, 2003. 相似文献
15.
响应面法优化鸡脂酶解工艺 总被引:1,自引:0,他引:1
通过单因素实验考察了脂肪酶、乳化剂、反应温度、pH值、反应时间、酶添加量及摇床转速等影响鸡脂脂肪酶水解的因素.采用响应面分析法对反应温度、酶添加量、pH值和反应时间等工艺参数进行了优化研究.结果表明,二次多项式模型符合实验数据.反应获得较优酸值时反应参数条件为:温度46.6℃,加酶量0.5%,pH值6.4,反应时间4.33 h. 相似文献
16.
目的 研究沿面介质阻挡放电(Surface Dielectric Barrier Discharge,SDBD)等离子体对生鲜鸡胸肉的杀菌作用及品质影响。方法 采用放电功率为260 W的SDBD等离子体分别处理生鲜鸡胸肉2 min和4 min,并于4 ℃贮藏12 d。每隔3 d取样,测定菌落总数、色泽、pH、汁液流失率、硫代巴比妥酸反应物(Thiobarbituric Acid Reactive Substances,TBARS)含量、挥发性盐基氮(Total Volatile Basic Nitrogen,TVB-N)含量及质构特性。结果 经SDBD等离子体处理2 min或4 min,并于4 ℃贮藏12 d后,生鲜鸡胸肉的菌落总数分别为7.16 lg(CFU/g)和6.70 lg(CFU/g),均低于对照组样品的菌落总数(7.55 lg(CFU/g))。此外,SDBD等离子体处理能够显著(P<0.05)改善冷藏期间鸡胸肉的品质参数,如pH、色泽(L*、a*和b*)、汁液流失率、TVB–N含量和质构特性(硬度、弹性、咀嚼性等),但对脂质氧化具有促进作用。结论 SDBD等离子体对生鲜鸡胸肉具有良好的杀菌效果,并有效保持了其品质,在鸡胸肉保鲜上具有巨大的应用前景。 相似文献
17.
《Food Control》2014
An improved gas chromatography method for the simultaneous separation of 52 fatty acids (FAs) has been developed. For both oleic acid and linoleic acid, a good resolution was achieved for their positional and geometrical (cis/trans) isomers. This method was validated to be precise, accurate and sensitive. With this method, the FAs profiles in palm oil and chicken fillets were analyzed. In general, small changes were observed in the composition of FAs and formation of trans isomers after 8 h frying at the temperature lower than 200 °C. However, with extreme deep-frying process, the thermal degradation and TFAs formation in frying oil increased in direct proportion to frying temperature and time. Moreover, the FAs composition of fried chicken fillets was found to be mostly in correspondence with that of the frying oil, which might be due to the oil absorption or interaction between the frying oils and frying materials. 相似文献
18.
Jitendra Sharma Prabhakaran Ponnusamy Pazhaniandi Vinay Kumar Tanwar Sudip Kumar Das Meena Goswami 《International Journal of Food Science & Technology》2012,47(1):61-66
This investigation was carried out to evaluate the antioxidant effect of turmeric (turmeric 1000 ppm, turmeric 5000 ppm), nitrite (nitrite 200 ppm) and ascorbic acid (ascorbic acid 500 ppm) on raw minced chicken stored at 4 ± 1 °C. Physicochemical properties [pH, water activity, cooking loss, thiobarbituric acid (TBA) value, peroxide value (PV), free fatty acid (FFA)] were evaluated on 0, 2, 4 and 6th day of storage. Highly significant differences (P < 0.01) in pH, TBA value, PV and FFA value were noticed between treatments and between storage periods. TBA values were observed to be lowest for nitrite 200 ppm and then turmeric 5000 ppm, and there was no significant difference between nitrite 200 ppm and turmeric 5000 ppm, and both were superior to ascorbic acid 500 ppm and turmeric 1000 ppm. Among different treatments, PV was found to be lowest in turmeric 5000 ppm and highest in nitrite 200 ppm. FFA value was found to be lowest in turmeric 5000 ppm and highest in ascorbic acid 500 ppm among all treated samples. It can be concluded that turmeric has potential to replace synthetic antioxidants presently used in meat processing with many added advantages. 相似文献
19.
Effect of claw disorders on milk production,fertility, and longevity,and their economic impact in Spanish Holstein cows 总被引:1,自引:0,他引:1
The aims of this study were (1) to estimate the phenotypic association between different degrees of severity of claw disorders and production, fertility performance, and longevity in Spanish dairy cattle, and (2) to quantify its economic impact at the animal and herd level. In this study, claw data comprised 108,468 trimmings collected between 2012 and 2014 by 25 trimmers from 804 Holstein dairy herds. The claw disorders considered were the 3 most frequent disorders in Spanish dairy herds: dermatitis (DE), sole ulcer (SU), and white line disease (WL). The presence of SU or WL was associated with a significant decrease in milk production and was more important in cows in second or later lactations. A severe lesion of SU or WL lead to twice the milk losses associated with a mild lesion, ranging from 1.47 to 2.66 kg/d of energy-corrected milk. The presence of SU or WL during the early lactation period was associated with more days open, fewer inseminations to get pregnant, and longer calving to first service interval (4.83 and 8.0 d longer due to mild and severe lesions of SU, respectively, and 4.94 and 17.43 d longer due to mild and severe lesions of WL, respectively). The occurrence of a case of SU or WL in first lactation had a significant effect on longevity, with severe lesions reducing up to 71 d of productive life. The cost of a mild lesion ranged from $53 to $232 per affected cow and year, whereas the cost of a severe lesion ranged from $402 to $622 per affected cow and year. The annual costs per cow for DE, SU, and WL were $10.80, $50.9, and $43.2, respectively. An average herd with 64 cows had an extra expenditure of $691/yr due to DE, $3,256/yr due to SU, and $2,765/year due to WL. Milk losses, longer calving intervals, and premature culling contributed to more than half of the costs. Therefore, providing this information to farmers could help decide on strategies to reduce the incidence of claw disorders on the farm. 相似文献
20.
《Drug development and industrial pharmacy》2013,39(9):1273-1276
Objective: The aim of this study was to evaluate and compare the permeation of model drug indomethacin (IND) from various types of gels through several semipermeable membranes.Methods: Permeation of IND from gels based on carbomer (CA), hydroxyethylcellulose (HEC), and polyacrylamid/laureth-7/isoparaffin was performed via diffusion cell method through membranes: shed snake skin, full thickness chicken skin, mucosa of pork small intestine, and cellophane.Results: The least permeation of IND was observed in the case of shed snake skin and full thickness chicken skin. It did not exceed 5.4% of original amount in the preparation after 3?h of measurement regardless the type of gel. In the case of mucosa of pork small intestine and cellophane the permeated amount of IND ranged from 9.4 to 55.4% depending on the type of gelling agent used. There was also quite a significant influence of a gelling agent on the permeation of IND observed. The permeation of IND was highest from CA gel, where it ranged from 0.6 to 52.2% of original amount in the preparation depending on the type of membrane used. Gelling agent inhibiting the permeation the most was HEC, where the permeated amount of IND did not exceed 12.3% regardless the type of membrane used.Conclusions: In general the permeated amount of IND through biological membranes containing stratum corneum represented just a small part of the amount in original preparation. Gelling agent has significant effect on the extent and rate of permeation. 相似文献