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41.
研究了不同配比的红磷阻燃母料(RPM)与氢氧化镁(MH)协同阻燃高抗冲聚苯乙烯(HIPS)体系的阻燃性能和机械性能。并选取最佳红磷阻燃母料与氢氧化镁的配比,再分别与其他无卤阻燃剂如酚醛树脂、氧化锌、氰尿酸三聚氰胺盐、有机纳米蒙脱土复配来共同阻燃HIPS,并分别对其体系的机械性能和阻燃性能进行了研究。结果表明,在RPM/MH质量比为1,总质量分数为30%时,与7%的酚醛树脂或有机纳米蒙脱土复配,都可以使阻燃HIPS材料达到1.6 mm UL94的V-1级。 相似文献
42.
目的 对目前市售的红谷黄酒类产品(无其他辅料添加)的营养价值及安全性进行分析评价。方法 采用比色法对产品的总蛋白、总多糖、总多酚、总黄酮、总皂苷、尿素含量及自由基清除能力进行测定,利用高效液相色谱法对γ-氨基丁酸(γ-aminobutyric acid, GABA)、苯甲酸及生物胺(biogenic amine, BA)含量进行测定,比较市售红谷黄酒产品的组间差异以及与其他类型黄酒产品的异同。结果 市售红谷黄酒产品拥有较高的营养价值,其中SC品牌黄酒具有较高的GABA与总皂苷含量,GC品牌黄酒具有较高的总多酚与总黄酮含量,同时具有最佳的体外抗氧化能力。从安全性角度分析,除SC品牌黄酒中总BA含量较高外,其余市售红谷黄酒产品的BA含量以及所有产品的尿素含量均处于较低水平,苯甲酸均未检出。结论 市售红谷黄酒产品相较于其他原料酿造的产品,具有更高的营养价值与较强的抗氧化性能,且产品的总体饮用安全性较高。本研究明确了红谷黄酒的产品优势,为红谷黄酒的推广提供数据支撑。 相似文献
43.
《Ceramics International》2020,46(5):5757-5764
Hexagonal ferrites can be employed in a multitude of applications, the most common hexaferrites are the M ferrites such as BaFe12O19 (barium hexaferrite, BaM). It is known that if Fe3+ is substituted with a combination of Ti4+/Co2+ the coercivity of BaM can be reduced to produce soft M ferrites with easily switchable magnetisation. They can be utilised as powders, films or bulk ceramics, and can be manufactured from a wide variety of synthesis methods. The production of hexaferrites usually requires commercial raw materials, but if an industrial waste can be utilised, this will help to ease waste disposal and storage costs, valorise a waste material and encourage circular economy. In this study, bauxite residue (red mud) from the production of alumina was used to synthesise M-type hexaferrites, using a simple ceramic process. BaCO3, or BaCO3+Co3O4, were added to the red mud, blended and heated at 1000 °C to produce the M-type hexaferrites. Without cobalt addition up to 81.1 wt% M ferrite was produced, and with Co addition up to 74.3 wt% M ferrite was formed. Without cobalt, the M ferrite phase closely resembled BaFe9Al3O19, and was a hard ferrite with a magnetisation of 12–19 A m2/kg for the whole powder (up to 23.6 A m2/kg for the M ferrite phase) and a coercivity of ~290 kA/m. When cobalt was added, secondary titanate phases vanished, and Ti4+/Co2+ partially substituted very soft M ferrite was formed with a low coercivity of ~16 kA/m but a higher magnetisation of 24.5 A m2/kg for the whole powder (up to 34.9 A m2/kg for the M ferrite phase). Therefore, not only can good quality magnetic materials be easily produced from this common waste material, but its magnetic properties can be tuned by varying the 2 + ions added during the process. 相似文献
44.
Eu~(3+)-doped hydrocalumites (Eu~(3+)-doped CaAl-LDH) were prepared in an ethanol/water media. Various techniques, including inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), and fluorescent spetctra (FL), etc., were employed to study the structure, composition,and fluorescence of samples. Compositional analyses reveal that the contents of all the elements calculated from the chemical formula are close to that of the actual found from measurement. XRD results suggest that the samples with different molar ratios of Ca~(2+)/(Al~(3+)+Eu~(3+)) present typical layered structure. Moreover, all the samples exhibit monoclinic structure. Fluorescent spectra show strong red emissions ascribed to~5D_0→~7F_J(J=1, 2) transitions of Eu3+ions for all the Eu~(3+)-doped hydrocalumites,revealing that the hydrocalumite is favorable for the emission of Eu~(3+). The Eu~(3+)-doped hydrocalumite may be a latent fluorescent material applied in biological or medical fields in consideration of the biocompatibility of Ca~(2+) ions and fluorescent property of Eu~(3+) ions. 相似文献
45.
Soo-Yeong ParkHee Kyoung Lim Seogjae LeeHyeong Cheol Hwang Somi K. ChoMoonjae Cho 《Food chemistry》2012,132(1):487-492
Pepsin-solubilised collagen (PSC) from Red Sea cucumber (Stichopus japonicus) was studied with respect to its wound-healing effects on a human keratinocyte (HaCaT) cell line. Disaggregated collagen fibres were treated with 0.1 M NaOH for 24 h and digested with pepsin for 72 h to reach maximum yield of 26.6%. The results of an in vitro wound-healing test showed that migration of HaCaT cells was 1.5-fold faster on PSC-coated plates than on untreated plates. The migration rate of sea cucumber PSC was similar to that of rat PSC, but five times higher than that of bovine gelatin. HaCaT cells grown on PSC-coated plates revealed increased fibronectin synthesis (6-fold and 3-fold compared to gelatin and rat PSC, respectively). Additionally, sea cucumber PSCs induced HaCaT cell proliferation by decreasing the G1 phase by 5% and maintaining a larger population (8%) of cells in mitosis. Collagen from Red Sea cucumber might be useful as an alternative to mammalian collagen in the nutraceutical and pharmaceutical industries. 相似文献
46.
47.
A comparative study of the purification of betanin 总被引:3,自引:0,他引:3
Letícia Christina Pires GonçalvesMarco Aurélio de Souza Trassi Nathana Barbosa LopesFelipe Augusto Dörr Monica Teixeira dos SantosWilhelm Josef Baader Vani Xavier Oliveira Jr.Erick Leite Bastos 《Food chemistry》2012,131(1):231-238
Betanin is a natural pigment with antioxidant properties used as a food colourant. This work describes the spectrophotometric and chromatographic quantification of betanin (2S/15S) and its epimer isobetanin (2S/15R) in fresh beetroot juice, food-grade beetroot powder and betanin standard diluted in dextrin. Absorption spectra of all three samples were deconvoluted using a mixed three-function model. Food-grade beetroot powder has the largest amount of violet-red impurities, probably formed during processing. The purification of betanin from these complex matrices was carried out by seven different methods. Ion exchange chromatography was the most efficient method for the purification of betanin from all samples; however, fractions contain high amounts of salt. Reversed-phase HPLC as well as reversed-phase column chromatography also produced good results at a much faster rate. The longer retention time of isobetanin when compared to betanin in reversed-phase conditions has been investigated by means of quantum-mechanical methods. 相似文献
48.
49.
本文以红辣椒为原料,考察了提取辣椒红色素的几个影响因素,确定了提取辣椒红色素的优化条件。实验结果表明,提取的最佳条件为:提取溶剂为石油醚,原料粒度为20~40目,液固比为9:1mL/g,提取时间4h。 相似文献
50.
Hui-Chao Chen Chang-Sui Zhao Yong-wang Li Duan-Feng Lu 《Korean Journal of Chemical Engineering》2007,24(5):906-910
An incineration test of a toxic chemical organic waste liquid was conducted on a circulating fluidized bed (CFB) incinerator.
The flue gas was measured online with the advanced SAE-19 flue gas analyzer. The effects of several factors, in terms of flow
rate of waste liquid, ratio of waste liquid injected into dense bed of the CFB, excess air coefficient, the secondary air
fraction and bed temperature on NO
x
emissions, were verified. The experimental results show that NO emissions in flue gas increase with increase in the flow
rate of the waste liquid injected into the bed or the excess air coefficient or the bed temperature and those decrease with
increase in the ratio of waste liquid injected into the dense bed of the CFB or the secondary air fraction. During the test
runs, NO
x
concentration in flue gas met the national regulation on NO
x
emissions due to suppressive effect of low temperature and staged combustion in CFB on NO
x
formation.
This paper was presented at the 6
th
Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006. 相似文献