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91.
Deirdre P. Lowe Helge M. Ulmer Douwe Van Sinderen Elke K. Arendt 《Journal of the Institute of Brewing》2004,110(2):133-140
In this study four strains of lactic acid bacteria (LAB) were chosen to bioacidify a mash containing 50% barley and 50% malt. The strains were isolated from malted and unmalted barley and assayed for extracellular enzymatic activities (proteases, amylases, β‐glucanases). The biologically acidified mash was compared to a chemically acidified mash, 100% malt mash un‐acidified and 50% malt and 50% barley mash unacidified. Characteristics such as pH, extract, colour, viscosity, total soluble nitrogen (TSN), free amino nitrogen (FAN), apparent fermentability, β‐glucan and lautering performance of the resultant worts were determined. A model lautering system replicating one used in a brewery was designed and built in University College Cork (UCC) to measure the lautering performance of the bioacidified mashes. The new system was compared to the filtration method used in EBC method 4.5.1. Overall the addition of LAB to bioacidify a mash of 50% barley and 50% malt resulted in faster filtration times, which correlated with decreased β‐glucan levels. Proteolytic LAB had a positive influence on the quality of wort and resulted in increased FAN levels. Lighter colour worts were observed along with increased extract levels. 相似文献
92.
Martin Zarnkow Matthias Keßler Felix Burberg Werner Back Elke K. Arendt Stefan Kreisz 《Journal of the Institute of Brewing》2007,113(3):280-292
Response surface methodology was used to investigate the influence of the three malting parameters, i.e. degree of steeping, germination time, and temperature on the quality of proso millet malt. Each predictor variable was tested at three levels. Germination times varied from 5, 6, and 7 days, degrees of steeping were 44, 48, and 52%, and germination temperatures were 16, 20, and 24°C. A set kilning temperature of 65°C was used for all malts. A series of malt quality parameters were investigated including extract, apparent attenuation limit, gelatinisation temperature, α‐amylase activity, β‐amylase activity, limit dextrinase activity, Kolbach index, α‐amino nitrogen, viscosity, and colour. The optimal malting program was achieved after the fifth day of germination, 44% degree of steeping, and a 22°C steeping and germination temperature. The obtained values for the amylolytic and cytolytic attributes were 64.8% extract, 1.383 mPa × s viscosity, 76.0% apparent attenuation limit, 111 U/g α‐amylase activity, and 102 U/g β‐amylase activity. 相似文献
93.
94.
Blaise Patricia Nic Phiarais Hilde Henny Wijngaard Elke Karin Arendt 《Journal of the Institute of Brewing》2005,111(3):290-298
This study investigated the impact of kilning on α‐amylase, β‐amylase (total and soluble), β‐glucanase and protease activities in buckwheat malt. Common buckwheat (Fagopyrum esculentum) was steeped at 10°C for 12 h, germinated at 15°C for 4 days and kilned at 40°C for 48 h. Moisture content and enzymatic activities were determined throughout the kilning period. Results showed moisture content was reduced from 44% to 5% after 48 h of kilning at 40°C. β‐Amylase was found to exist in a soluble and latent form in buckwheat. Maximum activity of (a) α‐amylase, (b) total β‐amylase, (c) soluble β‐amylase, (d) β‐glucanase and (e) protease activity occurred after (a) 8, (b) 7, (c) 30, (d) 0, and (e) 8 h of kilning, respectively. The final malt exhibited very little β‐glucanase and cellulase activity. Proteolytic activity was low in buckwheat malt when compared to the barley malt control. All enzymatic activities were found to decrease during the kilning stage. Results indicated that after prolonged kilning at 40°C, inactivation of hydrolytic enzymes occurred; two‐stage kilning for shorter periods is recommended. Although, amylolytic activity was low in malted buckwheat, buckwheat malt shows potential as an ingredient for the brewing and cereal industry. 相似文献
95.
超临界流体染色技术的过去、现在和将来(一) 总被引:17,自引:3,他引:17
介绍了超临界CO2染色技术在世界范围的发展过程及其优于水染色的特点。阐述了超临界CO2对纤维性能的影响,诸如润滑效果CO2吸附、结晶、收缩和热机械性能,超临界CO2对纤维的玻璃化温度和有效温度以及对纤维损伤的影响。另一重要问题是在超临界CO2中纤维与染料之间的平衡分布和影响染料溶解性的参数。文中给出了涤纶纤维的染色步骤、设备和最佳工艺参数,然而天然纤维的染色仍是一个问题。通过浸渍溶胀剂和交联剂,或在染色前对纤维改性、添加极性共溶剂,可以提高分散染料的染色性,所有这些方法增加了工艺步骤和设备清洗,若使用有机溶剂则将大大提高机器成本,采用活性分散染料可以避免这种情况。含乙烯砜基团的染料主要适宜于羊毛和聚酰胺纤维的超临界CO2染色,而对于纤维素纤维迄今尚未开发可行的解决方法。预计在不久的将来建造工业化规模的染色设备,努力实现超临界CO2染色技术的经济效益。 相似文献
96.
Breitling Lutz Philipp; Twardella Dorothee; Raum Elke; Brenner Hermann 《Canadian Metallurgical Quarterly》2009,23(2):362
The construct of self-efficacy, which is assessed either in confidence- or temptation-related instruments, presumably predicts transitions between the transtheoretical model stages of change and ultimately smoking cessation outcome. To elucidate its predictive potential for smoking cessation in a general care setting, we examined the association of baseline scores of the situational temptations inventory with month 12 smoking status in 577 heavy smokers participating in a cluster-randomized study of physician training and financial incentives for smoking cessation in Germany. At follow-up, abstinence could be validated in 56 patients. The temptation sub- and total scores were not bivariately associated with altered odds of smoking cessation, in contrast to established predictors like the Fagerstrom test of nicotine dependence and the stages of change. They were associated with the Fagerstrom scores, but not with the stages of change. Controlling for both cessation predictors, in particular the positive/social temptation subscore was associated with quitting. Additional studies are needed to fully understand how situational temptations relate to smoking cessation outcomes and explain variance beyond that of more established predictors of cessation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
98.
Road safety performance indicators (SPI) have recently been proposed as a useful instrument in comparing countries on the performance of different risk aspects of their road safety system. In this respect, SPIs should be actionable, i.e. they should provide clear directions for policymakers about what action is needed and which priorities should be set in order to improve a country’s road safety level in the most efficient way. This paper aims at contributing to this issue by proposing a computational model based on data envelopment analysis (DEA). Based on the model output, the good and bad aspects of road safety are identified for each country. Moreover, targets and priorities for policy actions can be set. As our data set contains 21 European countries for which a separate, best possible model is constructed, a number of country-specific policy actions can be recommended. Conclusions are drawn regarding the following performance indicators: alcohol and drugs, speed, protective systems, vehicle, infrastructure and trauma management. For each country that performs relatively poor, a particular country will be assigned as a useful benchmark. 相似文献
99.
Francisco A Toms‐Barbern Isabel Martos Federico Ferreres Branka S Radovic Elke Anklam 《Journal of the science of food and agriculture》2001,81(5):485-496
The HPLC phenolic profiles of 52 selected unifloral honey samples produced in Europe were analysed to detect possible markers for the floral origin of the different honeys. Lime‐tree (five markers), chestnut (five markers), rapeseed (one marker), eucalyptus (six markers) and heather (three markers) honeys had specific markers with characteristic UV spectra. In addition, the flavanone hesperetin was confirmed as a marker for citrus honey, as well as kaempferol for rosemary honey and quercetin for sunflower honey. Abscisic acid, which had been reported to be a possible marker for heather honey, was also detected in rapeseed, lime‐tree and acacia honeys. Ellagic acid in heather honey and the hydroxycinnamates caffeic, p‐coumaric and ferulic acids in chestnut, sunflower, lavender and acacia honeys were also detected. The characteristic propolis‐derived flavonoids pinocembrin, pinobanksin and chrysin were present in most samples in variable amounts. © 2001 Society of Chemical Industry 相似文献
100.
Elke Parkkinen Erkki Oura Heikki Suomalainen 《Journal of the Institute of Brewing》1976,82(5):283-285
The classical plate method for discriminating between viable and nonviable yeast cells in stored baker's yeast was compared with dead cell staining techniques using methylene blue and three fluorochrome stains. The increase of dead yeast cells during storage of baker's yeast for up to 16 days at 5°C, 20°C and 35°C was determined. During prolonged storage, especially at 35°C, the death rate increased rapidly and the yeast cake began to soften because of autolysis. In these conditions the choice of method for determining the proportion of dead cells proved to be of great importance. Useful results for yeast stored for some time at 35°C could be obtained only by the fluorochrome technique using primuline, acridine orange or acriflavine as fluorochromes. 相似文献