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Three humic acids(AHA, YHA, and EHA) from different origin were characterized by elementary analysis, UV-Vis and FTIR spectra, and the functional groups were determined by chemical titration. The effects of pH, time, temperature, and ionic strength on the complexation of three HAs with U(Ⅵ) were investigated systematically. Meanwhile, the interaction of U(Ⅵ) with three HA models in aqueous phase was studied by means of molecular dynamics(MD) simulations, and the dynamics, coordination structures, and interaction mechanism were further explored. The experimental results show that the elemental composition and functional group types of three HAs from different origin are basically similar, with strong aromaticity and conjugated double bonds, but slight differences can be also observed between them. The low H/C atom ratio, high acidity, and high content of functional groups indicate that YHA has high humification degree, high conjugation or aromatic composition, and strong metal complexation ability. The complexation behavior of three HAs with U(Ⅵ) are significantly different, which is substantially affected by pH, time, temperature, and ionic strength. MD simulations demonstrate that the complexation of single HA with U(Ⅵ) can be completed in a short time, and the main binding sites are carboxyl groups. The coordination structures formed by HAs with U(Ⅵ) in aqueous solution have quite differences, and the main driving force is electrostatic interaction. The results reported here are beneficial to further understanding the chemical behavior of uranium in the presence of HA, and provide data and reference for the geological disposal and safety evaluation of radioactive wastes.

Objective: The fatty acid composition of peony seed oil for oil of different varieties and different origins in the Loess Plateau was studied, and the differences in peony seed oil for different oils were compared and evaluated. Methods: Gansu ‘Paeonia rockii’, Gansu, Inner Mongolia, Shanxi, Shaanxi ‘Fengdan’ peony was used as raw materials, peony seed oil was prepared, the oil content and basic physical and chemical indicators of peony seed oil were determined, and the composition of seed oil fatty acids was studied by two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-TOFMS). Results: The oil content of ‘Paeonia rockii’ and ‘Fengdan’ peony seed were 27.97~36.12 g/100 g, the saponification value of peony seed oil were 141~152 mg/g, the peroxide value were 1.24~1.48 mmol/kg, the refractive index were 1.465~1.467, and the color was light yellow and translucent. Peony seed oils contained a total of 17 fatty acids, more nervous acid and tetracosanoic acid were detected than the GC-MS results. The α-linolenic acid and oleic acid in ‘Paeonia rockii’ from Gansu were significantly higher than those in ‘Fengdan’ peony, but the linoleic acid was lower than that (P

In this study, high performance liquid chromatography (HPLC) was used to determine the contents of nobiletin, tangeretin, hesperidin, naringin, limonin and synephrine in the first physiological fruit drop of mandarin orange, orange and pomelo from the main Citrus producing areas in China, such as Yichang in Hubei, Huaihua in Hunan, Chaozhou in Guangdong, Nanning in Guangxi, Zhangzhou in Fujian and Quzhou in Zhejiang. The purpose of comparing the characteristics of the content of effective active components in young fruits of Citrus plants from different habitats was to select Citrus cultivars with high nutritional value and rich active components, so as to lay a foundation for further extracting effective components and applying them to all aspects in the future. The results showed that: The contents of nobiletin and hesperidin in tangerine young fruits in Zhejiang Province were the highest, which were 359.63 μg/g and 222.14 μg/g, respectively. The content of naringin in the young fruit of Hubei Changyang grapefruit was the highest, which was 20.97 mg/g. The content of hesperidin in young fruits of Hubei Newhall orange was the highest, which was 1485.73 μg/g. The content of limonin in the young fruit of Guanxi grapefruit in Fujian was the highest, which was 866.73 μg/g. The content of synephrine in the young fruit of fertile orange in Guangxi was the highest, which was 1004.14 μg/g.

Construction and demolition wastes (CDW) are promising sources for geopolymer production; however, the great variability of CDWs arising from their origin causes an abstention from implementation. As one of the key challenges in the CDW management and recycling practices, origin-depended variations in the waste materials and their reflection on the final product performance can be overcomed through in-depth waste characterization and design optimization. To this end, this paper aims to characterize CDWs collected from five different demolition zones with regard to their physical-, chemical-properties and the mechanical performance of geopolymer pastes produced with them. The compressive strength of geopolymer pastes was found to be significantly influenced by the chemical composition, crystalline nature, and fineness of CDWs. Optimization of precursor characteristics resulted in consistent mechanical performance ranging from 54.5 to 68.0 MPa after curing at 115 °C for 48 hours, regardless of the CDW origin. The aluminosilicate and calcium content of the precursor heavily influenced the ultimate gel structure in a positive manner, which determined material strength. The optimized use of CDWs from the same source increased the compressive strength of geopolymer pastes by up to 64%. • CDWs from different demolition zones were characterized. • Physical, chemical and crystalline properties of CDWs were examined. • CDWs from 21 different origin were used to produce geopolymers. • Aluminosilicate content and fineness were dominant in mechanical performance. • Precursor-based optimization resulted in 54.5–68 MPa compressive strength. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to determine the influence of vermicompost with different origins on the development of cucumber seedlings. Three types of vermicompost produced by plant wast (PW), cow manure (CM) and a mixture from PW+CM were tested. In the mixture of peat and perlite in ration 3: 1 were added three quantities (5%, 10%, 15%) of each of investigated compost. The control was grown in the same mixture of peat and perlite. Some chemical properties: pH, contend of N, P, K of the vermicomposted were determined. In the end of seedling period was established that the vermicomposts has positive influence on the morphological signs and physiological indicators of the seedling plants. In most cases, the stimulation effect on the plants is enhanced by increasing the percentage of composts in the mixture. The plant height, leave number and area, chlorophyll content, fresh and dry weight on the plants, grown in peat and perlite mixture with 15% PW+CM of vermicompost there were the highest influence increased mostly in comparison with control. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)