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排序方式: 共有923条查询结果,搜索用时 839 毫秒
191.
K.-Y. Monica Lee Alistair Paterson Lorraine Birkmyre John R. Piggott 《Journal of the Institute of Brewing》2001,107(5):315-332
Flavour congeners in headspaces of 40 blended Scotch whiskies, of 4 different product categories (Deluxe, standard, retailer and West Highland), were collected by solid phase micro extraction (SPME) over 10 ml diluted (23% abv) whisky. Fibres (100 μm diameter) were thermally desorbed for 5 min in a split/splitless injection port and congeners quantified by high resolution gas chromatography. Two bonded SPME phases (polydimethylsiloxane and polyacrylate) were evaluated: exposure time was varied between 5 and 30 min; with whisky at either nosing (25°C) or tasting (37°C) temperature. Optimal analysis was with polyacrylate fibres at 37°C for 15 min but extraction at 25°C generated data relevant to sensory (nosing) data. Principal component (PCA) and discriminant partial least square (DPLS) analyses of mean % peak areas for all 57 resolved HRGC components and congeners (38) common to all whiskies gave product spaces showing clear separation of Deluxe, retailer and West Highland blends, but dispersed standard blends. In DPLS2 product clustering was similar whether relative (%) or absolute peak area was used in analyses but congeners loadings differed. From product spaces it was possible to assess contributions of flavour congeners, mainly esters and alcohols, to headspaces of individual blends and product categories. 相似文献
192.
以麦芽、大米、酒花为原料 ,对不同比例的麦芽用量作了小试 ,认为用45 %较55%为佳 ;辅料大米以37%为好 ,糖化pH5.2~5.4,糊化pH6.0~6.3,煮沸90min ,第一次加酒花2kg,第二次加酒花9kg,第三次加酒花7kg,接种酵母7.0‰ ,发酵最高温度12℃ ,最高压力0.12MPa,发酵第6天开始测双乙酰 ,当双乙酰降至0.8×10-7时 ,保温48h ,再以0.3℃/h降至0℃ ,后酵7天以上。成品酒理化指标达GB4929—91优级标准。 相似文献
193.
配醅串香工艺在浓香型白酒生产中的应用 总被引:4,自引:1,他引:3
根据甑桶蒸馏提香的充分条件,在生产中采取配醅串香工艺,将香醅,酒醅的蒸馏与发酵有机地组合起来,较好地解决了传统蒸馏方法中香味物质利用率低的问题,生产应用表明,配醅串香工艺能在稳定出酒率的基础上,提高优质品率13.1%,主体香味物质提高20%左右。 相似文献
194.
195.
The flavours of four beers were characterized by four panels of assessors, using a flavour profiling system. One panel carried out duplicate assessments. The results showed that training and experience improved reproducibility and discrimination, without distorting the general pattern of flavour terms reported. On the basis of the flavour profiles, the assessors could be divided into novices, those with some experience, and experts. Those novices likely to be good assessors could also be identified. 相似文献
196.
F. H. Schermers J. H. Duffus Anna M. MacLeod 《Journal of the Institute of Brewing》1976,82(3):170-174
An esterase (carboxylic acid hydrolase EC 3 1.1.1.) has been prepared from Saccharomyces cerevisiae. This esterase is active at pH 4.4 and, though it is unstable in solution, it can be maintained in an active form either by lyophilization or by coupling to an affinity gel. At pH 4.4, yeast esterase can hydrolyse between 20 and 40% of the esters commonly present in beer, and it is capable of synthesizing ethyl acetate from ethanol and acetic acid in a simple buffered solution without the provision of a co-factor. Different yeast strains yield different amounts of esterase, and there appears to be a positive correlation between the ability of the yeast to form esterase and the level of esters present in fermentations accomplished by that yeast. 相似文献
197.
198.
Alejandro Flores-Len Clara Perz Moro Raul Martí Joaquin Beltran Salvador Rosell Jaime Cebolla-Cornejo Belen Pic 《International journal of molecular sciences》2022,23(13)
Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation. 相似文献
199.
200.