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   81篇
  免费   6篇
化学工业   24篇
金属工艺   1篇
建筑科学   3篇
能源动力   2篇
轻工业   18篇
水利工程   2篇
石油天然气   1篇
无线电   9篇
一般工业技术   17篇
冶金工业   1篇
原子能技术   1篇
自动化技术   8篇
  2023年   2篇
  2022年   4篇
  2021年   7篇
  2020年   1篇
  2019年   1篇
  2018年   6篇
  2017年   4篇
  2016年   6篇
  2015年   2篇
  2014年   6篇
  2013年   5篇
  2012年   10篇
  2011年   9篇
  2010年   3篇
  2009年   5篇
  2008年   4篇
  2007年   6篇
  2006年   3篇
  2005年   1篇
  2004年   1篇
  2002年   1篇
排序方式: 共有87条查询结果,搜索用时 15 毫秒
1.
2.
3.
This study monitors variations in isotopes and elements in relation to grape variety, environmental factors and provenance in order to address the wine authenticity issue. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) assessed the wines’ elemental content. Site-specific nuclear isotope fractionation-nuclear magnetic resonance and isotope ratio mass spectrometry methodologies determined in authentic and commercial wines the distribution of the naturally occurring stable isotopes of the deuterium/hydrogen (D/H) ratios and carbon (13C/12C) in ethanol of wine and oxygen ratio (18O/16O) in wine water. Chemometrics delineated the elements and isotopes responsible for wine classification. Specifically, unsupervised principal component analysis (PCA) framed the importance of grape variety and provenance, while supervised analysis pinpointed the vineyard effect and highlighted the contribution of the vintage year. Validation steps ensured that the extracted models do not predict randomly and their results are reliable. In fact, the acquired results can be incorporated to the EU Wine Isotopic Databank database providing both a guide and a tool for eventual candidatures for denomination of origin and support both Cypriot wine and winemakers. In this context, this research contributes to authenticity assurance of wines and adds value to final products, while it helps controlling hazards arising from environmental changes.  相似文献   
4.
This paper investigates the influence of type of roadway, weather conditions and other factors on motorcycle helmet use rates in Iowa. Using data from six statewide roadside observational surveys of motorcycle helmet use, a bivariate probit model is estimated. The applied methodological approach allows for potentially interrelated choices of motorcycle helmet use by drivers and passengers to be examined. The estimation results can enhance our understanding of other factors than state helmet laws which correlate with motorcycle rider helmet use, and the effect that the presence of a passenger has on motorcycle driver helmet use rates.  相似文献   
5.
We present a patient with primary systemic AL‐amyloidosis, who stabilized hemodynamically on nocturnal hemodialysis (NHD). The NHD allowed a significant reduction in ultrafiltration rates which likely underlies the procedural tolerability. It also provided an increase in urea clearance, better control of serum phosphorus levels without the use of any binders, and normalization of blood pressure despite the discontinuation of all antihypertensive agents. Given the autonomic derangements associated with AL‐amyloidosis pathophysiology and the clinical benefits of NHD on hemodynamic stability, the use of intensive hemodialysis may be considered for the management of patients with unstable hemodynamic profiles.  相似文献   
6.
The evaluation of transportation projects has traditionally been made by assessing changes in travel time, vehicle operating cost, and safety. The broader, long-term effects on economic development (job, income and business growth) are a concern of transportation planners and decision makers, but have often been overlooked due to the lack of a reliable impact-estimation methodology and/or data. This paper presents a quantitative tool that can be used at the project-development phase to estimate the economic-development impacts of different types of highway construction projects. Using data from Indiana, we develop models that can be used to estimate the effects of geographic location, accessibility, and other factors on the economic-development impacts of highway construction projects. Our models can also be used as a basis for programming and ranking a wide variety of highway construction projects.  相似文献   
7.
In the present study, complexes of vanillin with β-cyclodextrin (β-CD) were prepared by the freeze-drying method. The formation of the inclusion complex was confirmed by differential scanning calorimetry (DSC). DSC thermograms indicated that the endothermic peak of vanillin and the physical mixture of vanillin with β-CD, due to the melting of vanillin crystals, were absent in DSC thermograms obtained for the freeze-dried inclusion complex. Moreover, the DSC studies under oxidation conditions indicate that the complex of vanillin with β-CD is protected towards oxidation since it remains intact at temperatures where the free vanillin is oxidising. The structure of the complex in aqueous solutions was established by nuclear magnetic resonance (NMR) studies and specifically by two-dimensional rotational frame NOE spectra. NMR studies showed inclusion of the entire vanillin molecule in the β-CD in a tilted manner and with the aldehyde group in the primary side. The stoichiometry of the complex was 1:1. A phase solubility study was performed by mixing an excess amount of vanillin with aqueous solutions containing increasing amounts of β-CD. The results indicated that the complex of a vanillin/β-CD inclusion is more soluble in water than vanillin alone.  相似文献   
8.
The objectives of the present study were (a) to produce gluten-free bread, fortified with iron (GFB-Fe), using selected iron compounds (ferric pyrophosphate, ferric pyrophosphate with emulsifiers, NaFeEDTA, electrolytic iron, ferrous gluconate, ferrous lactate and ferrous sulphate) (b) to test sensory characteristics of the GFB-Fe (feel-mouth texture, crumb colour, aroma and taste) (c) to compare iron dialyzability of various iron compounds in GFB-Fe. The most acceptable products were those fortified with ferric pyrophosphate with emulsifiers and ferric pyrophosphate. Ferrous dialyzable iron (ferrous iron with molecular weight lower than 8000 Da, an index for prediction of iron bioavailability) was measured under simulated gastrointestinal conditions. Ferrous dialyzable iron in GFB-Fe fortified with ferric pyrophosphate with emulsifiers, NaFeEDTA, ferrous bis-glycinate, ferrous gluconate or ferrous sulphate was higher than that in GFB-Fe fortified with electrolytic iron, ferrous lactate or ferric pyrophosphate (P < 0.05). These results are promising for the development of GFB-Fe products in the future.  相似文献   
9.
10.
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