首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   931篇
  免费   74篇
  国内免费   2篇
综合类   23篇
化学工业   70篇
机械仪表   4篇
建筑科学   3篇
能源动力   2篇
轻工业   897篇
水利工程   1篇
一般工业技术   3篇
冶金工业   1篇
原子能技术   1篇
自动化技术   2篇
  2024年   7篇
  2023年   13篇
  2022年   37篇
  2021年   37篇
  2020年   44篇
  2019年   31篇
  2018年   34篇
  2017年   35篇
  2016年   43篇
  2015年   34篇
  2014年   34篇
  2013年   55篇
  2012年   45篇
  2011年   54篇
  2010年   26篇
  2009年   26篇
  2008年   32篇
  2007年   28篇
  2006年   26篇
  2005年   31篇
  2004年   18篇
  2003年   21篇
  2002年   25篇
  2001年   8篇
  2000年   10篇
  1999年   18篇
  1998年   18篇
  1997年   13篇
  1996年   7篇
  1995年   9篇
  1994年   11篇
  1993年   8篇
  1992年   13篇
  1991年   5篇
  1990年   11篇
  1988年   6篇
  1987年   9篇
  1986年   6篇
  1985年   8篇
  1984年   11篇
  1983年   10篇
  1982年   8篇
  1981年   6篇
  1980年   9篇
  1979年   9篇
  1978年   12篇
  1977年   10篇
  1976年   7篇
  1974年   18篇
  1973年   5篇
排序方式: 共有1007条查询结果,搜索用时 15 毫秒
1.
A combustion method, relying on the Dumas principle, for the determination of total nitrogen in barley and malt, has been collaboratively tested by the Analysis Committee of the European Brewery Convention. Repeatability, r95, and reproducibility, R95, values were 0.063 and 0.116% of dry matter, respectively, for samples with nitrogen contents in the range 1.23 to 1.86% N of dry matter. There was no significant difference between these values for barley and malt. The Analysis Committee approved the adoption of the combustion method for inclusion in Analytica EBC as an alternative method.  相似文献   
2.
In earlier studies concerning vigour, where subsamples are heat‐treated before germination there was found heat‐sensitive as well as heat‐resistant barley samples. The vigour model developed by Ellis and Roberts and further developed at Carlsberg, could only describe the heat‐sensitive barleys. Seventeen samples of the “Alexis” variety grown widely in Europe were collected from the EBC trials in 1994 in order to see if heat resistance in barley was influenced by different growing conditions. We found both heat‐sensitive samples following the vigour model as well as pronounced heat‐resistant samples, but these were not divided according to growing conditions. The germination curves dependent on heat treatment and germination time were evaluated by Principal Component Analysis (PCA). Heat‐resistant barley samples could be differentiated from heat‐sensitive samples already after ½ h of heat treatment at 68°C (12% moisture) and after 3 days of germination. The barley samples were analysed with regard to malting quality. The PCA evaluation of the data divided the samples according to growing location, mainly due to differences in protein and β‐glucan. However, the malting analyses could not describe the differences in heat resistance and sensitivity of the barleys. The biochemical background of the heat resistance found is discussed on the basis of literature. Our findings should give an experimental basis for exploiting a biochemical principle for heat resistance, which is formed during grain filling and consumed during storage and germination.  相似文献   
3.
Forty-three lines of barley, including ancestral (wild), landraces, Middle Eastern lines, and modern cultivars, were grown under two different sets of environmental conditions. Hordenine production in barley roots was determined at the one-leaf stage by HPLC analysis and, in two lines only, over a period of 35 days. Forty-two of the 43 lines produced significant amounts of hordenine, although there was no variation among groups. Middle Eastern lines had the highest production with 327 µg/g on a dry weight basis. Production was, however, determined more by environmental conditions during growth than by genetic factors. Hordenine production was up to seven times higher in plants grown under lower light intensities.  相似文献   
4.
Dimethyl sulphoxide (DMSO) is a normal component of malt and barley. A method is described for its extraction and estimation. DMSO is produced by the oxidation of dimethyl sulphide (DMS), particularly during kilning of malt, and higher levels are found in malts subjected to ale kilning schedules. DMS may also be oxidized during wort preparation. DMSO can be reduced to DMS by yeast in glucose/salts medium, by yeast cell suspensions and by a cell-free extract. Reduction of DMSO is inhibited by methionine sulphoxide. The results suggest that reduction of DMSO may account for the DMS produced during fermentation of ale and lager worts.  相似文献   
5.
A survey of the use of pesticides in maltings, breweries and distilleries during the period April 1974 to March 1975 was made by the Pesticides Survey Group at the Ministry of Agriculture's Pest Infestation Control Laboratory at Slough in collaboration with the Department of Agriculture and Fisheries for Scotland. A breakdown of the insecticides and rodenticides used, including quantities and numbers of users, is given. The results show that in most cases, the official recommended measures to control pests are being followed.  相似文献   
6.
赵生元 《酿酒科技》2007,5(4):107-108
以青稞、红景天、茶叶为原料,经清洗、粉碎、液化、加曲发酵、压榨、调配、过滤、杀菌等工序生产红景天青稞茶酒,成品酒色泽淡黄、晶莹透明、香气自然,酒度3%Vol-5%Vol,酸度小于0.28,茶酒同饮、药食同源,具有饮用功能互补、协同显效的双重作用。(孙悟)  相似文献   
7.
This study was undertaken to investigate the diversity and population structure of 83 spring barley (Hordeum vulgare L.) cultivars, which corresponded to 120 years of this crop’s breeding in Poland. The analysis was based on 11,655 DArTseq-derived SNPs evenly distributed across seven barley chromosomes. Five groups were assigned in the studied cultivars according to the period of their breeding. A decrease in observed heterozygosity within the groups was noted along with the progress in breeding, with a simultaneous increase in the inbreeding coefficient value. As a result of breeding, some of the unique allelic variation present in old cultivars was lost, but crosses with foreign materials also provided new alleles to the barley gene pool. It is important to mention that the above changes affected different chromosomes to varying degrees. The internal variability of the cultivars ranged from 0.011 to 0.236. Internal uniformity was lowest among the oldest cultivars, although some highly homogeneous ones were found among them. This is probably an effect of genetic drift or selection during their multiplications and regenerations in the period from breeding to the time of analysis. The population genetic structure of the studied group of cultivars appears to be quite complex. It was shown that their genetic makeup consists of as many as eleven distinct gene pools. The analysis also showed traces of directed selection on chromosomes 3H and 5H. Detailed data analysis confirmed the presence of duplicates for 11 cultivars. The performed research will allow both improvement of the management of barley genetic resources in the gene bank and the reuse of this rich and forgotten variability in breeding programs and research.  相似文献   
8.
9.
Following field trials in 2008 and 2010, six lines, derived by mutation in the hull‐less barley cultivar Penthouse, were selected to provide a range in grain β‐glucan content. These lines, along with Penthouse and the hulled, malting variety Optic, were then malted, using four different steeping regimes, with samples kilned after 3, 4 and 5 days of germination. The longest steep regime provided samples with optimum modification after 5 days of germination. Samples from the other steep regimes were under‐modified to varying degrees. In particular, the steeps with a single immersion gave poorly modified samples with low extracts and alcohol yields. One line, with low grain β‐glucan, gave higher alcohol yields than either Penthouse or Optic, following a regime comprising two short immersions and a single air‐rest, but there was no clear association, within the lines, between β‐glucan content and malting properties. Copyright © 2012 The Institute of Brewing & Distilling  相似文献   
10.
The barley chloroplast mutator (cpm) is a nuclear gene mutant that induces a wide spectrum of cytoplasmically inherited chlorophyll deficiencies. Plastome instability of cpm seedlings was determined by identification of a particular landscape of polymorphisms that suggests failures in a plastome mismatch repair (MMR) protein. In Arabidopsis, MSH genes encode proteins that are in charge of mismatch repair and have anti-recombination activity. In this work, barley homologs of these genes were identified, and their sequences were analyzed in control and cpm mutant seedlings. A substitution, leading to a premature stop codon and a truncated MSH1 protein, was identified in the Msh1 gene of cpm plants. The relationship between this mutation and the presence of chlorophyll deficiencies was established in progenies from crosses and backcrosses. These results strongly suggest that the mutation identified in the Msh1 gene of the cpm mutant is responsible for the observed plastome instabilities. Interestingly, comparison of mutant phenotypes and molecular changes induced by the barley cpm mutant with those of Arabidopsis MSH1 mutants revealed marked differences.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号