全文获取类型
收费全文 | 372篇 |
免费 | 40篇 |
专业分类
化学工业 | 168篇 |
金属工艺 | 3篇 |
机械仪表 | 8篇 |
建筑科学 | 5篇 |
能源动力 | 3篇 |
轻工业 | 144篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 7篇 |
一般工业技术 | 34篇 |
冶金工业 | 11篇 |
原子能技术 | 4篇 |
自动化技术 | 20篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 40篇 |
2021年 | 41篇 |
2020年 | 15篇 |
2019年 | 6篇 |
2018年 | 14篇 |
2017年 | 24篇 |
2016年 | 21篇 |
2015年 | 15篇 |
2014年 | 18篇 |
2013年 | 22篇 |
2012年 | 19篇 |
2011年 | 33篇 |
2010年 | 19篇 |
2009年 | 24篇 |
2008年 | 15篇 |
2007年 | 9篇 |
2006年 | 13篇 |
2005年 | 9篇 |
2004年 | 10篇 |
2003年 | 9篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1980年 | 2篇 |
排序方式: 共有412条查询结果,搜索用时 0 毫秒
81.
Antonio Bevilacqua Barbara Speranza Daniela Campaniello Milena Sinigaglia Maria Rosaria Corbo 《Food and Bioprocess Technology》2014,7(8):2189-2197
This paper reports on the use of ultrasound (US) as a suitable strategy to control the growth of spoiling yeasts in fruit juices. In a first phase, US technique was tested towards Saccharomyces cerevisiae inoculated in different juices (strawberry, orange, apple, pineapple and red-fruits): the treatment was performed by modulating the level of the power (20–60 %), the duration of the treatment (2–6 min) and the pulse (2–6 s), according to a fractional design. Then, the best treatment was applied against some other spoiling yeasts (Pichia membranifaciens, Wickerhamomyces anomalus, Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Candida norvegica). Finally, a challenge test for a commercial beverage (red-fruit juice), inoculated with Z. bailii and containing a citrus extract, was conducted evaluating the effect of US on the sensory scores of the beverage. The results showed that the effect of US was mainly influenced by the power and the duration of the treatment; on the other hand, the effect of pulse was less significant and slight. The highest reduction of S. cerevisiae was found in the following combination of the design: power 60 %/time 4 min/pulse 2 s and power 60 %/time 6 min/pulse 6 s; this result was confirmed for the other spoiling yeasts. US and citrus extract could be combined to prolong the shelf life of the red-fruit juice and control the growth of Z. bailii. The two hurdles exerted a different role and acted in different times: US reduced the initial contamination, whilst citrus extract controlled the yeast within the storage. 相似文献
82.
Attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy was evaluated to measure fatty acids (FA) and total lipids in intact seed barley (Hordeum vulgare) samples. Results from this study demonstrated the capability of ATR-MIR spectroscopy coupled with partial least squares (PLS) regression to measure FA non-destructively in intact barley seeds. The coefficients of determination in cross validation (R2) and the standard error of cross validation (SECV) were 0.76 and 0.004 g 100 g−1 for stearic, 0.75 and 0.037 g 100 g−1 for oleic, 0.45 and 0.02 g 100 g−1 for palmitic acids, and 0.89 and 0.13 g 100 g−1 for total lipids, respectively. The practical implications of this study showed that ATR-MIR spectroscopy confer valuable benefits for the grain industry and in particular in breeding programs as a non-destructive high throughput method. 相似文献
83.
84.
Albenzio M Marino R Caroprese M Santillo A Annicchiarico G Sevi A 《The Journal of dairy research》2004,71(4):434-443
Effects of ventilation regimen on the quality of ewes' milk and on proteolysis in Canestrato Pugliese cheese during ripening were studied. Cheeses were manufactured from the bulk milk of Comisana ewes subjected to three different ventilation regimens, which were designated low (LOV, 23 m3/h per ewe), moderate (MOV, 47 m3/h per ewe) and programmed ventilation regimen (PROV, 73 m3/h per ewe; fan set to maintain 70% relative humidity). Bulk milk was analysed for chemical and microbial composition, renneting parameters and plasmin-plasminogen activities. At 1, 15, 30 and 45 d of ripening, the cheeses were analysed for gross chemical composition, nitrogen fractions, and plasmin and plasminogen activities. The pH 4.6-insoluble nitrogen fractions were analysed by urea-PAGE. Free amino acid content was determined at the end of ripening. Lower concentrations of bulk milk somatic cell count (BMSCC) and of mesophilic bacteria were found in the MOV group than in the LOV and the PROV groups. A lower plasminogen (PG) to plasmin (PL) ratio (PG/PL) was observed in the MOV and PROV than in the LOV cheeses. Irrespective of treatment, PL activity in cheeses was higher at 15d of ripening, while a sudden decrease of PL and PG activities was observed at 30 d, which was associated with a marked increase in non-protein nitrogen. The peptide profile characterized in the urea-PAGE showed a greater intensity of alpha- and beta-CN hydrolysis in the MOV than in the PROV and LOV cheeses. The results provide evidence that a proper ventilation regimen is critical for optimizing the hygienic quality of milk and the proteolysis of Canestrato Pugliese cheese during ripening. 相似文献
85.
Steeping is the first operation of malting and its purpose is to increase the water content of the grain up to 43–46%; however, such a simple step encompasses several metabolic processes that affect germination and the final malt quality. The aim of this study was to evaluate the effect of initial grain protein (GP) content and starch pasting properties, measured using the Rapid Visco Analyser (RVA) on water uptake in different barley varieties. The partial least squares (PLS2) regression algorithm was used to compare the two data matrices, the independent block of variables X (RVA data and GP) and the dependent block Y (water uptake at different steeping times). The first two PLS2 loadings explained 65 and 23% of the total variation in water uptake in the barley samples. Water uptake at 1 and 2 h was poorly explained by the PLS2 models, while after 5 h the models explained more than 40% of the variability. The results from this study showed that, although a relationship between GP and water uptake exists, it is not universal for all the varieties, indicating that the relationship between GP and water uptake is varietal dependent. Copyright © 2014 The Institute of Brewing & Distilling 相似文献
86.
Molecularly imprinted polymers: present and future prospective 总被引:2,自引:0,他引:2
Vasapollo G Sole RD Mergola L Lazzoi MR Scardino A Scorrano S Mele G 《International journal of molecular sciences》2011,12(9):5908-5945
Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented. 相似文献
87.
Rosaria Cozzolino Beatrice De Giulio 《European Journal of Lipid Science and Technology》2011,113(2):160-167
Triacylglycerols (TAG) are the most important group of compounds present in vegetable oils. These biomolecules, determining the physical, chemical and nutritional properties of the oils, are considered to be good fingerprints for quality and authenticity control. Therefore, TAGs characterization is a very important task in edible oil field, which has been undertaken by different analytical methods. The analysis of vegetable oils is still dominated by classic determinations, which are however laborious and time‐consuming and cannot be used routinely. More recently, advances in MS instrumentations coupled with online separation techniques and data processing have contributed to great expansion of MS in oil study, allowing the development of innovative analytical approaches that exhibit higher sensitivity, accuracy and rapidity in vegetable oils investigations. In the present contribution, a review of the most relevant applications of novel mass spectrometric techniques, such as ESI and MALDI, both alone and hyphenated with HPLC, used for analysis of the complex TAGs mixture of edible oils is illustrated. 相似文献
88.
Volpini R Marucci G Buccioni M Dal Ben D Lambertucci C Lammi C Mishra RC Thomas A Cristalli G 《ChemMedChem》2011,6(6):1074-1080
Guanosine, released extracellularly from neurons and glial cells, plays important roles in the central nervous system, including neuroprotection. The innovative DELFIA Eu‐GTP binding assay was optimized for characterization of the putative guanosine receptor binding site at rat brain membranes by using a series of novel and known guanosine derivatives. These nucleosides were prepared by modifying the purine and sugar moieties of guanosine at the 6‐ and 5′‐positions, respectively. Results of these experiments prove that guanosine, 6‐thioguanosine, and their derivatives activate a G protein‐coupled receptor that is different from the well‐characterized adenosine receptors. 相似文献
89.
Dal Ben D Antonini I Buccioni M Lambertucci C Marucci G Thomas A Volpini R Cristalli G 《ChemMedChem》2011,6(7):1163-1171
Neuropeptide?S (NPS) is a 20-amino acid peptide of great interest due to its possible involvement in several biological processes, including food intake, locomotion, wakefulness, arousal, and anxiety. Structure-activity relationship studies of NPS have identified key points for structural modifications with the goal of modulating NPS receptor (NPSR) agonist activity or achieving antagonism at the same receptor. Only limited information is available for nonpeptide NPSR antagonists. In the last year, several studies have been reported in literature which present various series of small molecules as antagonists of this receptor. The results allow a comparison of the structures and activities of these molecules, leading to the design of new ligands with increased potency and improved pharmacological and pharmacokinetic profiles. This work presents a brief overview of the available information regarding structural features and pharmacological characterization of published nonpeptide NPSR antagonists. 相似文献
90.
Claudio Colleoni Maria Rosaria Massafra Veronica Migani Giuseppe Rosace 《应用聚合物科学杂志》2011,120(4):2122-2129
Textile finishing includes all processes that help to maintain the value or increase the value of the textile material. It encompasses dyeing, printing, and all the finishing treatments to realize durable press, soil release, flame retardant, antistatic, antimicrobial, or water/oil repellency properties. When these properties are realized on dyed textile fabric, one effect could be ascribed to the color change induced by finishing operations. This research focuses on the assessment of color alterations occurring on the dyed cotton/polyester blended fabrics due to the nanoparticle‐sized dendrimer (DWR), dendrimer–fluorocarbon (DWOR), and fluorocarbon (FWOR) finishing onto their surfaces. The dependence of color on the surface state of treated textiles is calculated in the context of spectrophotometric measurements. Modification of the surface roughness by reflectance spectrum and the absorbance of finishes in visible range were investigated to determine color changes between the original (control fabric, dyed but not treated) and treated fabrics. As a result of color matching calculated by CIE‐Lab values, color change is related to the surface roughness associated with absorbance values of applied finishes. In addition, fabrics mechanical properties were evaluated to estimate if finishing agents application gives rise to other changes, besides color alterations. The fabrics mechanical properties have been found not significantly altered by the aforementioned finishing treatments. These results could be applied for industrial needs (quality control), or in the artistic field of conservation, or restoration (to follow the color of paintings). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献