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51.
Jeong-Beom Lee Young-Oh Shin Jun-Sang Bae Young-Ki Min Hun-Mo Yang Hyung-Seok Seo Dae-keun Kwon Jun-yong Kang Young-ju Song 《Food science and biotechnology》2010,19(3):671-675
This study investigated the anti-inflammatory effects of Pellinus linteus (PL) extract supplementation in healthy young men. The subjects were 18 healthy young males 20 years of age that were given
1.5 L of 0.12% PL extract orally (n=8) or a placebo (control group, n=10) daily for 4 weeks. The body composition, the white blood cell (WBC) count and differential as well as the serum cortisol,
interleukin (IL)-1β, and IL-6 concentrations were measured before and after the supplementation. Serum concentrations of cortisol
and IL-1β at rest after oral supplementation were significantly decreased compared to before treatment (p<0.01, p<0.05, respectively). However, there was no change in the IL-6. And also, these factors in PL extract supplement group were
significantly reduced after performing the exercise compared to control group. These results suggest that oral PL extract
supplements for 4 weeks had a significant effect on inhibition of inflammatory markers in healthy young men. 相似文献
52.
Microelectrodes are among the most accurate and reliable monitoring devices for measuring the dynamics of biofilm processes. This paper describes a novel needle-type microelectrode array (MEA) for simultaneous in situ measurements of dissolved oxygen (DO) and oxidation reduction potential (ORP) fabricated using microelectromechanical systems (MEMS) technologies. The MEA exhibits fast response times for both DO and ORP measurements and shows a substantial increase in DO sensitivity. To demonstrate the versatility of the new sensor, it was applied to the measurement of DO and ORP microprofiles in a multispecies biofilm. This work demonstrates that the MEA is able to monitor local concentration changes with a high spatial resolution and provide the versatility of the microelectrode technique needed for biofilm studies as well as the capability for repetitive measurements. In addition, the use of MEMS technologies and batch fabrication approaches enables integration, high consistency, high yields, and mass production. With further development, it may be possible to add additional sensors to the MEA (e.g., pH, phosphate) and integrate them with a reference electrode. 相似文献
53.
Seon Hwa Cheon Hye Young Seo Young Bae Chung Ho Hyun Chun 《International Journal of Food Science & Technology》2016,51(2):470-479
The effects of electron beam irradiation on microbial inactivation and quality of noninoculated and inoculated (Listeria monocytogenes) kimchi pastes were examined. Kimchi paste samples were irradiated at doses of 2, 4, 6, 8 and 10 kGy and stored for 21 days at 4 °C. Irradiation (10 kGy) reduced the populations of total aerobic bacteria, lactic acid bacteria, and yeast and moulds in the samples by 1.72, 2.24 and 0.86 log CFU g?1, respectively, compared to the control. In particular, coliforms were not detected at 8 and 10 kGy, and the population of L. monocytogenes in inoculated samples was significantly decreased by 2.67 log CFU g?1. Electron beam irradiation delayed the changes in O2 and CO2 concentrations, pH, acidity and reducing sugar content observed in kimchi paste during storage. These results suggest that electron beam irradiation can be used to improve the microbiological safety and shelf life of kimchi paste. 相似文献
54.
The main objective of this study was to check the feasibility of the newly proposed hydrate-based chlorinated hydrocarbon (CHC) recovery process for removing chlorinated hydrocarbons from aqueous solutions. Two key process variables of hydrate phase equilibria and formation kinetics were closely examined to develop the overall conceptual design of this technology. First, the ternary four-phase (H-LW-LCHC-V) hydrate equilibria of aqueous solutions containing methylene chloride (CH2Cl2), carbon tetrachloride (CCl4), 1,2-dichloroethane (CH2ClCH2Cl), 1,1,1-trichloroethane (CH3CCl3), and 1,1-dichloroethylene (CH2= CCl2) were measured at various temperature and pressure conditions using three different types of help gases (CO2, N2, CH4). The help gas + water + chlorinated hydrocarbons systems greatly reduced the hydrate-forming pressure, which confirmed the mixed hydrates with chlorinated hydrocarbons more stabilized than the simple hydrates consisting of a help gas and water. The degree of stabilization was found to follow the order of 1,2-dichloroethane < 1,1-dichloroethylene < methylene chloride < 1,1,1-trichloroethane < carbon tetrachloride. For the N2 + water + carbon tetrachloride system, the formation pressure reduction as much as 96% was observed at 279.35 K. Second, the formation kinetic experiments of carbon dioxide hydrates containing chlorinated hydrocarbons were conducted under isothermal and isobaric conditions. The consumption rate of carbon dioxide gas became fast at the early time of the growth period, gradually decreased, and finally went to the complete hydration. The proposed hydrate-based recovery process appears to be very simple from the operational point of view because no special facilities requiring sensitive and complex function are needed. Another advantage is that this process only requires carbon dioxide as a hydrate former. Best of all, this process can be applied to separation and recovery of other organic pollutants dissolved in aqueous solutions without changing the basic concept. 相似文献
55.
Sae Bom Lim Jagan Mohan Rao Tingirikari Ji Sun Seo Ling Li Sangmin Shim Jin-Ho Seo Nam Soo Han 《Food science and biotechnology》2018,27(1):73-78
Lactic acid bacteria (LAB) are key for the fermentation of sourdoughs to improve the quality and nutritive value of bread. The aim of this study was to isolate the LAB starter for sourdough fermentation from Jeung-pyun, a Korean traditional rice cake. Among the twenty two LAB screened, five isolates were selected based on exo-polysaccharide production. Among them, three isolates showed cell growth greater than 8.5 Log CFU/g, maximum increase in the volume of dough, and dextran concentration up to 0.16%. During the sourdough fermentation, pH and total titratable acidity (TTA) were changed, as the three isolates synthesized lactic acid and acetic acid with fermentation quotients less than 2.0. They were identified as Leuconostoc lactis EFEL005, Lactobacillus brevis EFEL004, and Le. citreum EFEL006. They displayed good fermentation properties (growth, dextran production, pH, and TTA) in dough and they are regarded as potential starters to be used in sourdough fermentation. 相似文献
56.
Skin ageing is accompanied by wrinkle formation. In particular, periorbital wrinkle formation is a relatively early sign of skin ageing. We evaluated the effects of a preparation containing asiaticoside on the periorbital wrinkles of a group of volunteers. The effectiveness of the active compound, asiaticoside, in a base-cream preparation for the treatment of temporal periorbital wrinkles was tested on 27 female volunteers as follows: the women applied the cream twice a day to the region of interest for 12 weeks. Same women also applied a vehicle control cream to the periorbital skin around the other eye. Negative replicas were taken of the periorbital skin before treatment and 4, 8, and 12 weeks after application of the cream. The results were evaluated by semi-automated morphometry of the plastic replicas. After 12 weeks of treatment, there was a significant improvement of the periorbital wrinkles in majority of the volunteers who tested the cream. Of the 27 women examined with periocular wrinkles, 65% showed an improvement at the end of the treatment. In three cases, the improvement was 100% (disappearance of the crow's feet), 75% +/- 1.97 and 79% +/- 2.82. On six eyes, there was no significant change after the treatment. With 12 weeks of treatment with the asiaticoside-containing cream, most of the periorbital wrinkles were attenuated to some degree, and some women experienced a significant improvement of the periorbital wrinkles on one of their eyes. 相似文献
57.
Salmonellosis caused by Salmonella Enteritidis (SE) is a significant cause of foodborne illnesses in the United States. Consumption of undercooked eggs and egg-containing products has been the primary risk factor for the disease. The importance of the bacterial enumeration technique has been enormously stressed because of the quantitative risk analysis of SE in shell eggs. Traditional enumeration methods mainly depend on slow and tedious most-probable-number (MPN) methods. Therefore, specific, sensitive, and rapid methods for SE quantitation are needed to collect sufficient data for risk assessment and food safety policy development. We previously developed a real-time quantitative PCR assay for the direct detection and enumeration of SE and, in this study, applied it to naturally contaminated ice cream samples with and without enrichment. The detection limit of the real-time PCR assay was determined with artificially inoculated ice cream. When applied to the direct detection and quantification of SE in ice cream, the real-time PCR assay was as sensitive as the conventional plate count method in frequency of detection. However, populations of SE derived from real-time quantitative PCR were approximately 1 log higher than provided by MPN and CFU values obtained by conventional culture methods. The detection and enumeration of SE in naturally contaminated ice cream can be completed in 3 h by this real-time PCR method, whereas the cultural enrichment method requires 5 to 7 days. A commercial immunoassay for the specific detection of SE was also included in the study. The real-time PCR assay proved to be a valuable tool that may be useful to the food industry in monitoring its processes to improve product quality and safety. 相似文献
58.
Jung Youngmi Kim Inyoung Mannaa Mohamed Kim Jinnyun Wang Sihyung Park Inmyoung Kim Jieun Seo Young-Su 《Food science and biotechnology》2019,28(1):261-267
Food Science and Biotechnology - Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disorders. Possible links have been recently found between the gut-microbiota and the host... 相似文献
59.
Preenrichment versus direct selective agar plating for the detection of Salmonella Enteritidis in shell eggs 总被引:4,自引:0,他引:4
Valentín-Bon IE Brackett RE Seo KH Hammack TS Andrews WH 《Journal of food protection》2003,66(9):1670-1674
The relative effectiveness of two methods for the recovery of Salmonella Enteritidis (SE) from jumbo and medium shell eggs was compared. The first method used in the comparison consisted of a preenrichment of the sample, and the second method was developed by the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS). Three bulk lots of blended, pooled eggs, each containing 220 liquid whole eggs that were thoroughly mixed manually were artificially inoculated with different levels of SE cells between approximately 10(0) and 10(3) CFU/ml. Twenty samples containing the contents of approximately 10 eggs each (by weight) were withdrawn from each of the inoculated bulk lots and incubated for 4 days at room temperature (ca. 23 degrees C). For the APHIS method, each sample was cultured by direct plating onto brilliant green (BG), brilliant green with novobiocin (BGN), xylose lysine desoxycholate (XLD), and xylose lysine agar Tergitol 4 (XLT4) agars. For the preenrichment method, 25-g portions from each pool were enriched in modified tryptic soy broth with 30 mg/liter of FeSO4. After 24 h of incubation, the preenrichments were subcultured to tetrathionate and Rappaport-Vassiliadis broths, and streaked to BG, BGN, bismuth sulfite, XLD, and XLT4 agar plates. SE isolates were confirmed biochemically and serologically. In all of the experiments, the preenrichment method recovered significantly more SE isolates (P < 0.05) of all the phage types and inoculum levels than did the APHIS method. From a total of 539 jumbo egg test portions analyzed, 381 (71%) were SE-positive by the preenrichment method and 232 (43%) were positive by the APHIS method. From a total of 360 medium egg test portions analyzed, 223 (62%) were SE-positive by the preenrichment method and 174 (48%) were positive by the APHIS method. The preenrichment method provided greater sensitivity for the isolation of SE in contaminated egg slurries than did the APHIS method. 相似文献
60.
Effects of Leuconostoc mesenteroides starter cultures on microbial communities and metabolites during kimchi fermentation 总被引:1,自引:0,他引:1
Jung JY Lee SH Lee HJ Seo HY Park WS Jeon CO 《International journal of food microbiology》2012,153(3):378-387
Kimchi fermentation usually relies upon the growth of naturally-occurring various heterofermentative lactic acid bacteria (LAB). This sometimes makes it difficult to produce kimchi with uniform quality. The use of Leuconostoc mesenteroides as a starter has been considered to produce commercial fermented kimchi with uniform and good quality in Korea. In this study, a combination of a barcoded pyrosequencing strategy and a 1H NMR technique was used to investigate the effects of Leu. mesenteroides strain B1 as a starter culture for kimchi fermentation. Baechu (Chinese cabbage) and Chonggak (radish) kimchi with and without Leu. mesenteroides inoculation were prepared, respectively and their characteristics that included pH, cell number, bacterial community, and metabolites were monitored periodically for 40 days. Barcoded pyrosequencing analysis showed that the numbers of bacterial operational taxonomic units (OTU) in starter kimchi decreased more quickly than that in non-starter kimchi. Members of the genera Leuconostoc, Lactobacillus, and Weissella were dominant LAB regardless of the kimchi type or starter inoculation. Among the three genera, Leuconostoc was the most abundant, followed by Lactobacillus and Weissella. The use of Leu. mesenteroides as a starter increased the Leuconostoc proportions and decreased the Lactobacillus proportions in both type of kimchi during kimchi fermentation. However, interestingly, the use of the kimchi starter more highly maintained the Weissella proportions of starter kimchi compared to that in the non-starter kimchi until fermentation was complete. Metabolite analysis using the 1H NMR technique showed that both Baechu and Chonggak kimchi with the starter culture began to consume free sugars earlier and produced a little greater amounts of lactic and acetic acids and mannitol. Metabolite analysis demonstrated that kimchi fermentation using Leu. mesenteroides as a starter was completed earlier with more production of kimchi metabolites compared to that not using a starter, which coincided with the decreases in pH and the increases in bacterial cell number. The PCA strategy using all kimchi components including carbohydrates, amino acids, organic acids, and others also showed that starter kimchi fermented faster with more organic acid and mannitol production. In conclusion, the combination of the barcoded pyrosequencing strategy and the 1H NMR technique was used to effectively monitor microbial succession and metabolite production and allowed for a greater understanding of the relationships between the microbial community and metabolite production in kimchi fermentation. 相似文献