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排序方式: 共有470条查询结果,搜索用时 15 毫秒
101.
Alina Culetu Anicuta Stoica-Guzun Denisa Eglantina Duta 《International Journal of Food Science & Technology》2021,56(1):126-137
This study investigated the effect of six fats (margarine, butter, lard-LAR, refined palm oil-RPO, refined palm oil with stearin-RPOS, hydrogenated palm oil-HPO) with different solid fat content (SFC) on gluten-free oat dough and cookie properties. RPOS and HPO had the highest SFC. RPO dough was the softest, whereas HPO was the hardest one. Dough hardness was correlated with SFC (r = 0.87). Dough stickiness was positively correlated with dough hardness (r = 0.92). Dough hardness influenced the breaking force of the cookies (r = 0.79). HPO were the hardest cookies. Oscillatory test revealed that HPO dough was the stiffest as well as presented a higher rigidity compared to the other samples as showed by the creep tests. LAR cookies were the darkest, while HPO were the lightest. SFC of fats is the most important composition parameter which influences thermal, textural and rheological properties of the oat dough. 相似文献
102.
Alina A. Manshina Alexey V. Povolotskiy Anastasia V. Povolotskaya Tatiana Yu. Ivanova Igor O. Koshevoy Sergey P. Tunik Mika Suvanto Tapani A. Pakkanen 《Surface & coatings technology》2012
Heterometallic (Au–Cu) phase precipitation on the surface of soda-lime glass as a result of laser-induced chemical liquid phase deposition (LCLD) is demonstrated for the first time. The precipitation of heterometallic structures was carried out under Ar+ laser irradiation from the solutions of supramolecular complexes. Energy dispersive X-ray (EDX) analysis showed that the deposits consist of both Au and Cu. Morphology of the deposited structures was found to be dependent on the used solvents: delocalized sparse surface structures in the case of the dichloromethane solution, close packed nanoparticles for the dimethyl formamide and homogeneous phase with nano-pores for the acetone solution. In accordance to the SEM photos and scan EDX analysis the homogeneous heterometallic phase with fixed Au/Cu ratio was achieved for the acetone solution of supramolecular complex. The observed formation of the heterometallic phase was explained by the laser-initiated intramolecular reduction process of the supramolecular metal core. 相似文献
103.
Raman Mnatsakanyan Davit Davtyan Alina Zurnachyan Suren Kharatyan Edward Karakhanov Argam Akopyan Khachatur Manukyan 《Ceramics International》2018,44(18):22339-22344
A simple and efficient microwave-assisted preparation of ReB2-based material is reported utilizing ammonium perrhenate (NH4ReO4), magnesium boride (MgB12) reactants and carbon as an absorber of microwave irradiation. The investigation of microwave irradiated NH4ReO4 +MgB12 +C mixtures, thermal analysis results and electron microscopy examination reveals that NH4ReO4 decomposition produces ReO3 at early stages of the process. The ReO3 then exothermically reacts with MgB12 forming the nanoscale Re3B phase, which converts into ReB2 upon further irradiation. The coupling of microwave energy with exothermic reactions significantly accelerates the formation of ReB2. The product primarily consists of ReB2 as well as B4C and minor carbon phases. Structural characterization reveals that the average particle size of ReB2 is ~ 50?nm. 相似文献
104.
Rafael Luque Alina Mariana Balu Juan Manuel Campelo Camino Gonzalez-Arellano Maria Jose Gracia Diego Luna Jose Maria Marinas Antonio Angel Romero 《Materials Chemistry and Physics》2009,117(2-3):408-413
The facile preparation of a range of supported nanoparticles on porous materials was successfully accomplished through the use of a range of environmentally friendly protocols including a modified impregnation/reduction methodology, ultrasounds and microwave irradiation. Materials were characterised by transmission electron microscopy (TEM) and XPS. Different morphologies including conventional nanospheres, nanoflower aggregates, nanorod-like structures and nanocubes were achieved under different conditions. The reported supported nanoparticles are envisaged to have interesting applications in various areas including catalysis, optics and sensors. 相似文献
105.
Morphological changes and covalent reactivity assessment of single-layer graphene oxides under carboxylic group-targeted chemistry 总被引:1,自引:0,他引:1
Acid–base titrations were used to assess the covalent reactivity of carboxylic groups on single-layer graphene oxides (SLGO) or hydrazine-reduced analogues (SLGR) when treated with thionyl chloride and subsequent coupling to amines. Reflux with aggressive solvents led to size reduction and folding of individual sheets as well as loss of carboxylic groups, substantially so for SLGR. Room temperature treatment of SLGO with a carbodiimide collapsed the sheets into star-like clusters, which exhibited poor subsequent reactivity with amines. Ultimately, conventional chemical treatment of carboxylic groups on SLGO leads to morphological changes and reduced reactivity, which may potentially limit their use. 相似文献
106.
Florica Adriana Nicolescu Valentin Victor Jerca Dumitru Mircea Vuluga Dan Sorin Vasilescu 《Polymer Bulletin》2010,65(9):905-916
New side-chain poly(methacrylate)s with azo moieties were prepared by free radical copolymerization, starting from methyl
methacrylate (MMA) and some original azo-monomers. The chromophore content was evaluated from 1H-NMR spectroscopy and elemental analyses; all structures exhibited a high content of azobenzene units. UV–Vis measurements
have also supported this fact. Reactivity ratios for the methacrylate systems and their corresponding Q–e values were calculated based on several initial feed compositions (MMA and the newly synthesized azo-monomers) using an integral
method with its appropriate software. The polymers were also characterized by FTIR, SEC and DSC-TGA techniques. The coloured
poly(methacrylate)s exhibited glass transition temperatures between 141 and 168 °C and thermal stabilities up to 306 °C. 相似文献
107.
This article focuses on correlating the column classification obtained from the method created at the Katholieke Universiteit Leuven (KUL), with the chromatographic resolution attained in biomedical separation. In the KUL system, each column is described with four parameters, which enables estimation of the FKUL value characterising similarity of those parameters to the selected reference stationary phase. Thus, a ranking list based on the FKUL value can be calculated for the chosen reference column, then correlated with the results of the column performance test. In this study, the column performance test was based on analysis of moclobemide and its two metabolites in human plasma by liquid chromatography (LC), using 18 columns. The comparative study was performed using traditional correlation of the FKUL values with the retention parameters of the analytes describing the column performance test. In order to deepen the comparative assessment of both data sets, factor analysis (FA) was also used. The obtained results indicated that the stationary phase classes, closely related according to the KUL method, yielded comparable separation for the target substances. Therefore, the column ranking system based on the FKUL-values could be considered supportive in the choice of the appropriate column for biomedical analysis. 相似文献
108.
109.
Trees in sacral and utilitarian practice: the value of nature and ecology in the life of the Selkups
Yuri I. Ozheredov Alina Y. Ozheredova Sergey Kulizhskiy 《The International journal of environmental studies》2014,71(5):761-767
The study represents an interdisciplinary analysis of the material and symbolic nature of the trees in the culture of Siberian indigenous people. The work is based on the archaeological, ethnographic and linguistic materials related to one of the Siberian aboriginal peoples, the Selkups. The results of the linguistic study of mythology, ethnographic research and archaeological excavations of the burial sites (16th–17th) allowed us to build up a model of the Selkup attitude to the most important elements of nature, in their view, the tree. To make a comparative analysis, the work considers the materials related to the neighbouring ethnic groups that were similar in their culture and the worldview. The study discusses the problem of continuing of the tradition in the period of 16th–20th centuries. Based on the structural analysis of the gathered materials, the authors came to the conclusion that the Selkup traditional perception of the trees remained unchanged within the discussed period. The continuation of the tradition allowed the Selkups to preserve the metaphysical perception of nature and their place in it. The close connection of man and nature became the basis for keeping the ecological balance and, as a result, protecting the society. 相似文献
110.
A new and efficient route using inexpensive reagents such as fumed silica and tetrapropylammonium bromide is proposed for the synthesis of titanium silicalite-1. High crystalline titanium silicalite-1 was obtained in alkaline medium, using sodium hydroxide as HO? ion source required for the crystallization process. Hydrolysis of titanium source with formation of insoluble oxide species was prevented by titanium complexation with before structuring gel. The final solids were fully characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared, ultraviolet-visible diffuse reflectance, Raman and atomic absorption spectroscopies, as well as nitrogen sorption analysis. It was found that a molar ratio Ti:Si of about 0.04 in the initial reaction mixture is the upper limit to which well formed titanium silicalite-1 with channels free of crystalline or amorphous material can be obtained. Above this value, solids with MFI type structure containing both Ti isomorphously substituted in the network and extralattice anatase nanoparticles inside of channels is formed. 相似文献