全文获取类型
收费全文 | 573篇 |
免费 | 35篇 |
专业分类
电工技术 | 7篇 |
综合类 | 3篇 |
化学工业 | 125篇 |
金属工艺 | 1篇 |
机械仪表 | 6篇 |
建筑科学 | 24篇 |
矿业工程 | 3篇 |
能源动力 | 4篇 |
轻工业 | 208篇 |
石油天然气 | 1篇 |
无线电 | 24篇 |
一般工业技术 | 77篇 |
冶金工业 | 78篇 |
原子能技术 | 2篇 |
自动化技术 | 45篇 |
出版年
2023年 | 11篇 |
2022年 | 14篇 |
2021年 | 26篇 |
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 22篇 |
2015年 | 19篇 |
2014年 | 31篇 |
2013年 | 22篇 |
2012年 | 33篇 |
2011年 | 37篇 |
2010年 | 30篇 |
2009年 | 31篇 |
2008年 | 29篇 |
2007年 | 24篇 |
2006年 | 24篇 |
2005年 | 28篇 |
2004年 | 20篇 |
2003年 | 18篇 |
2002年 | 18篇 |
2001年 | 10篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 20篇 |
1997年 | 14篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 8篇 |
1976年 | 3篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1959年 | 1篇 |
1904年 | 1篇 |
1902年 | 1篇 |
排序方式: 共有608条查询结果,搜索用时 15 毫秒
71.
The effect of the fungal infection Fusarium
graminearum and Fusarium
culmorum on naked barley cultivars (n = 7) with respect to the barley’s total protein content and the content of the protein fractions albumins + globulins, prolamins
(hordeins) and glutelins (hordenins) was investigated. A summer barley cultivar (n = 1) was used for comparison. The total protein content of the whole grain flours was very variable, ranging from 125 to
225 g kg−1. The influence of Fusarium infection showed that the content of hordeins and hordenins was slightly reduced, while the albumins and globulins were not
affected. In addition, the effect of the two different growing locations on the protein content of the naked barley was also
evaluated. It could be shown that the C-hordeins, γ-hordeins and D-hordenins were significantly positively affected by increasing
nitrogen supply, whereas the B-hordenin content was significantly negatively influenced. Nitrogen availability seems to be
a factor that promotes gene expression for hordeins but reduces the synthesis of the main B-hordenins. 相似文献
72.
Paul Sullivan John O’Flaherty Nigel Brunton Elke Arendt Eimear Gallagher 《European Food Research and Technology》2010,231(3):441-453
Barley has long been known as a good source of fibre and in particular beta-glucan, but increased consumer awareness has meant
that this is only now being exploited by food scientists and the food industry. In this study, doughs and breads were produced
using pearled barley flour (PBF) in different ratios (30, 50, 70 and 100%) to wheat flour. A 100% wheat flour formulation
was used as a control. The flour formulations were evaluated for protein content; the dough rheological properties of the
formulations were evaluated using fundamental oscillatory tests and uniaxial extension tests. The baked breads were evaluated
for volume, texture, moisture, dietary fibre and beta-glucan. Digital image analysis of the crumb grain was also carried out.
Protein analysis revealed that increasing the amount of PBF in the formulation leads to a significant (p < 0.001) decrease in the protein content of the formulation. Starch pasting properties were also affected by an increase
in PBF concentration, with an increase in PBF significantly increasing the peak viscosity, breakdown, setback and final viscosity
of the starch slurries of the formulations. Extensional rheology revealed that increasing the PBF in the doughs leads to the
doughs rupturing at lower extensions and with a lower force. Bread volume between treatments was found to be significantly
(p ≤ 0.001) different, with an increase in PBF inclusion leading to smaller loaves. Texture profile analysis of the bread slices
showed that breads containing higher ratios of PBF had a significantly harder (p ≤ 0.001) and less cohesive (p ≤ 0.001) crumb. Low levels of PBF (≤50%) did not significantly effect loaf volume or crumb texture, however, and the total
dietary fibre and beta-glucan levels of the loaves were significantly increased (p ≤ 0.001) with increasing levels of PBF in the formulation, even at low levels of inclusion. 相似文献
73.
Edith K. Hüttner Fabio Dal Bello Elke K. Arendt 《European Food Research and Technology》2010,230(6):849-857
The use of sourdough in wheat and rye breads has been extensively studied; however, little is known about its potential effect when baking oat bread. Consequently, the impact of sourdough on oat bread quality was investigated. Two different sourdoughs were prepared from wholegrain oat flour without the addition of starter cultures, by continuous propagation at 28 (SD 28) or 37 °C (SD 37) until the composition of the lactic acid bacteria remained stable. The dominant LAB were identified by sequence analysis of the 16S rDNA isolated from pure cultures. LAB from SD 28 belonged to the species Leuconostoc argentinum, Pedicoccus pentosaceus and Weissella cibaria, while Lactobacillus coryniformis dominated SD 37. The isolated LAB were further used as starter cultures for the production of oat sourdoughs. Fundamental rheology revealed softening of the sourdoughs compared to non-acidified and chemically acidified controls, which could not be attributed to proteolytic activity. Incorporation of oat sourdough into an oat bread recipe resulted in significantly increased loaf-specific volume as well as improved texture, independent of addition level or sourdough type. Overall, the results of this study show that sourdoughs containing lactic acid bacteria isolated from oats have the potential to enhance oat bread quality. 相似文献
74.
Joachim Mittendorf Prof. Dr. Stefan Weigand Dr. Cristina Alonso‐Alija Dr. Erwin Bischoff Dr. Achim Feurer Dr. Michael Gerisch Dr. Armin Kern Dr. Andreas Knorr Dr. Dieter Lang Dr. Klaus Muenter Dr. Martin Radtke Dr. Hartmut Schirok Dr. Karl‐Heinz Schlemmer Dr. Elke Stahl Dr. Alexander Straub Dr. Frank Wunder Dr. Johannes‐Peter Stasch Dr. 《ChemMedChem》2009,4(5):853-865
Direct stimulation of soluble guanylate cyclase (sGC) represents a promising therapeutic strategy for the treatment of a range of diseases, including the severely disabling pulmonary hypertension (PH). Optimization of the unfavorable DMPK profile of previous sGC stimulators provided riociguat, which is currently being investigated in phase III clinical trials for the oral treatment of PH.
75.
Thermal comfort and satisfaction at workplaces – a field study in office buildings. By applying multivariate analysis to survey data of a field study in 17 buildings, several correlations between different parameters with regard to satisfaction at workplaces could be found and validated. One important result was that the individual satisfaction parameters were independent. A significant difference between winter and summer votes on the satisfaction with the indoor temperature could be shown; the dissatisfaction at neutral thermal sensation was considerably higher in summer. In total, only 30% of the occupants were very satisfied or satisfied with the temperature at their workplace in summer and winter. The perceived effectiveness of attempted temperature changes proofed to be the dominant parameter for the satisfaction with the indoor temperature. By weighting individual satisfaction parameters a matrix could be generated which provides a straight‐forward assessment of building performance by showing the optimisation potential for each parameter and the necessity to act for the building manager. The conclusion with regard to building design is that small office rooms with individual control of the indoor environment perform best in terms of acceptance by occupants. 相似文献
76.
Jinhua Wang Elke Pawelzik Joachim Weinert Qinghua Zhao Gerhard A. Wolf 《European Food Research and Technology》2008,226(6):1365-1371
The Hagberg falling number (HFN) is one of the most important quality characteristics of wheat. Six winter wheat cultivars
from three locations in Germany were analysed to assess the factors influencing the HFN. The cultivars and locations affected
significantly the HFN of all the samples. The infection with Fusarium culmorum, determined in another cultivar, also led to an increase in HFN, which suggested that the HFN method is not adequate enough
for the true determination of the alpha-amylase activity of fungus-infected, wheat flour. Furthermore, there was no clear correlation between HFN and thousand-kernel
weight, starch content or pentosan content. The crude protein content was positively related to the HFN, while the total dietary
fibre content depended on the cultivar and location. 相似文献
77.
Modifications of fruit quality, in response to a long-term salt stress of four months, were studied in two strawberry cultivars differing in their sensitivity to salinity. The sensitive cv. Elsanta and the less sensitive cv. Korona were treated during two vegetation seasons with 0, 40 or 80 mmol NaCl/l in the nutrient solution. While mean fruit weight decreased, dry matter and contents of total soluble carbohydrates, as well as sweetness index of fruits, remained constant. Salt stress in both cultivars increased the antioxidant capacity, antioxidants pools (ascorbic acid, anthocyanins, superoxide dismutase) and selected minerals such as Na+, Cl−, K+, N, P and Zn2+, as well as lipid peroxidation. Furthermore, salt stress increased the contents of free and essential amino acids, especially in cv. Elsanta. The more tolerant cv. Korona was characterized by an increase of reduced glutathione and a better fruit taste. In salt-stressed fruits of cv. Elsanta, taste was significantly impaired. 相似文献
78.
Contribution of amino acids to strawberry fruit quality and their relevance as stress indicators under NaCl salinity 总被引:2,自引:0,他引:2
Strawberry cvs Korona and Elsanta, differing in their sensitivity to salt stress, were exposed to 0, 40, or 80 mM NaCl in the root medium from the end of April to mid-August. Although fruits of both cultivars contained comparable amounts of Na+ and Cl−, fruit quality was more impaired in cv. Elsanta, as indicated by the larger reductions of fruit size and sugar/acid ratios. Malondialdehyde levels started to rise significantly at 40 mM NaCl in the more sensitive cv. Elsanta, but at 80 mM in cv. Korona. Total amino acid levels, especially contents of essential amino acids, rose significantly in both cvs. Salt stress also increased contents of free proline, asparagine, and glutamine. Their increases may contribute to osmotic adjustment. The results of the present study favour the interpretation that elevated levels of proline, asparagine and glutamine are indicative of salt stress damage. 相似文献
79.
Retrometabolic drug design approaches incorporate metabolic and toxicological considerations into the drug design process and represent a novel, systematic methodology for the design of safe compounds. Two major design concepts aimed to increase the therapeutic index (the activity/toxicity ratio) of drugs were developed. Chemical delivery systems (CDS) are primarily used to allow targeting of the active biological molecules to specific target sites or organs based on predictable enzymatic activation. Soft drug approaches are used to design new drugs by building in the molecule, in addition to the activity, the most desired way in which the molecule is to be deactivated and detoxified subsequent to exerting its biological effects. Special computer programs were developed that starting from a lead compound generate complete libraries of possible soft analogs and then help ranking these candidates based on isosteric-isoelectronic comparisons, predicted solubility/partition properties, and estimated metabolic rates. The novel field of large peptide-CDSs imposes special challenges, but a new, remarkably simple model was developed to estimate partition properties for a wide range of compounds, including quite large peptide derivatives. A suggested change of about five order of magnitudes in the distribution coefficient can explain the "lock in" mechanism of brain-targeting delivery systems. 相似文献
80.