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Anti-ultraviolet aging tests of asphalts adapting to environment in Tibetan Plateau of China 被引量:15
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作者 廖公云 黄晓明 巴桑顿珠 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期503-507,共5页
Ultraviolet (UV) aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene r... Ultraviolet (UV) aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene rubber (SBR) asphalts with different contents of three anti-UV-aging agents including nano-TiO2, CeO2 and carbon black are performed. Common indices, which include retained penetration after thin film oven tests (TFOT) and softening point, and strategic highway research program (SHRP) indices of aged asphalts are evaluated. Infrared absorption spectral analysis is performed on asphalt specimens with 0. 8% carbon black which have been aged for different aging times (500, 1000 and 1 500 h). By grey incidence analysis, the optimal contents of anti-UV-aging agents are determined. The results show that TiO2 and CeO2 are not only good UV absorbing or shielding agents, but also strong oxidants. Carbon black is a good anti-UV-aging agent, and its optimal content is about 0. 8% of asphalt weight. UV aging of asphalt mainly occurs in the early stages of aging. The longer the aging time, the more severe the aging of asphalt. 展开更多
关键词 ultraviolet (UV) aging agent carbon black infrared absorption spectral analysis grey incidence analysis
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Preliminary Identification of Red Pigment and Positive Correlation between the Contents of Red Pigment and Total Saponins of Panax notoginseng Fruits 被引量:1
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作者 赵昶灵 陈中坚 +3 位作者 陈文龙 支伟特 魏富刚 宋德功 《Agricultural Science & Technology》 CAS 2012年第9期1891-1895,共5页
[Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng frui... [Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng fruits was preliminarily identi- fied with specific color reactions and UV-vis spectra, and the contents of the pigment and total saponins were determined via spectrophotometry. [Result] The red hues of the fruits were contributed by anthocyanins and/or the anthocyanidins. The contents of anthocyanins and total saponins of the fruits both decreased along with thinning of the red hues. The content difference of the anthocyanins in fruits with different red hues reached extremely significant level, but that of total saponins just reached significant level. [Conclusion] The red pigment of P. notoginseng fruits is anthocyanins which are of extremely significant positive correlation with total saponins in contents. 展开更多
关键词 Panax notoginseng fruits Red pigment Anthocyanins Total saponins Content correlation
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Preparation of Conjugated Linoleic Acid and Identification of Its Isomers 被引量:9
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作者 郭诤 张根旺 孙彦 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期130-135,共6页
Conjugated linoleic acid (CLA) is a kind of fatty acid with physiological activities and potential application prospect. A synthesis method of conjugated linoleic acid and a purification technology were studied. CLA w... Conjugated linoleic acid (CLA) is a kind of fatty acid with physiological activities and potential application prospect. A synthesis method of conjugated linoleic acid and a purification technology were studied. CLA was prepared and purified by urea-complexation and conjugation using safflower oil as raw material. The purity of CLA and total recovery of the product was more than 95% and 48%, respectively. The main isomers produced in alkali-catalyzed conjugation were identified by gas chromatography (GC) linked to mass spectrometry (MS) and Fourier transform infrared spectroscopy (FTIR). The total amount of the two main isomers (9cis, 11trons-and 10trans, 12cis-CLA) determined by GC was more than 90% of the product. 展开更多
关键词 linoleic acid conjugated linoleic acid urea-complexation alkali-catalyzed conjugation IDENTIFICATION safflower oil
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Increase in functional groups for POSS by introducing branched phenylglycidylether 被引量:1
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作者 付强 胡立江 孙德智 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第1期17-22,共6页
In the selected experimental conditions, firstly, the branched products with functional groups, N-(2-hydroxylpropylphenylether) (3-aminopropyl) triethoxysilane (APES-PGE, containing one hydroxyl group) and N-[di... In the selected experimental conditions, firstly, the branched products with functional groups, N-(2-hydroxylpropylphenylether) (3-aminopropyl) triethoxysilane (APES-PGE, containing one hydroxyl group) and N-[di(2-hydroxylpropylphenylether)](3-aminopropyl) triethoxysilane (APES-PGE2, containing two hydroxyl groups), were synthesized by reacting 1 mole of (3-aminopropyl)triethoxysilane (APES) with 2 mole of phenylglycidylether (PGE). Then the hydrolytic condensation of APES-PGE and APES-PGE2 was performed by dissolving 1 g of the corresponding silane in 1.5 ml tetrahydrofuran (THF), adding water and eventually a catalyst (molar ratios: [H2O]/Si=3, [NaOH]/Si=0.05), and heating at 50 ℃ for 24 h, allowing continuous evaporation of volatiles. The final products with branches containing hydroxyl groups were polyhedral oligomeric silsesquioxanes (POSS). The products from two reactions were characterized by standard spectroscopic techniques, gel partition chromatography (GPC), Fourier-transformed infrared spectroscopy (FTIR) and matrix-assisted ultraviolet laser desorption/ionization time-of-flight mass spectrometry (UV-MALDI-TOF MS). Additionally, a narrow mass distribution of multifunctionalized POSS was shown by UV-MALDI-TOF MS and assignments of the MS peaks. 展开更多
关键词 aminopropyl)triethoxysilane (APES) phenylglycidylether (PGE) Polyhedral oligomeric silsesquioxanes (POSS) matrix-assisted ultraviolet laser desorption/ionization time-of-flight mass spectrometry (UV-MALDI-TOF MS)
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Extraction,Isolation and Structural Characterization of Polysaccharides from a Red Alga Gloiopeltis furcata 被引量:3
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作者 YU Guangli HU Yannan YANG Bo ZHAO Xia WANG Peipei JI Guoli WU Jiandong GUAN Huashi 《Journal of Ocean University of China》 SCIE CAS 2010年第2期193-197,共5页
Three kinds of polysaccharides: GFW, GFH and GFA, were sequentially extracted from a red alga Gloiopeltisfurcata with 25℃ and 85℃ water, and 60℃ 4% NaOH water solution. Based on the defatted alga, the yields of th... Three kinds of polysaccharides: GFW, GFH and GFA, were sequentially extracted from a red alga Gloiopeltisfurcata with 25℃ and 85℃ water, and 60℃ 4% NaOH water solution. Based on the defatted alga, the yields of the polysaccharide were 57.9%, 2.5% and 2.6%, respectively. Their monosaccharide compositions, average molecular weights and structural characters were determined by gas chromatography (GC), high performance liquid chromatography (HPLC), fourier transform infrared spectroscopy (FTIR) or ^13C-NMR spectroscopy. The results showed that GFW, GFH and GFA were all composed of D-galactose (Gal) and 3,6-anhydro-L-galactose (AnG), and particularly GFA also contained xylose (Xyl). The average molecular weights of GFW, GFH and GFA were 22.6 kD, 26.5 kD and 49.8 kD, respectively, with the respective sulfate content 31.2%, 25.1% and 22.7%. The data of FTIR and ^13C-NMR confirmed the sulfate ester location at C6 ofgalactose. It is concluded that all the three polysaecharides extracted from Gloiopeltisfurcata were sulfated galactans, two being sulfated-agarose, and one being xylose-containing sulfated galactan. 展开更多
关键词 Gloiopeltisfurcata sulfated galactan EXTRACTION structural characterization
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Synthesis of Some New Diazo Disperse Dyes and Their Application on Dyeing of Polyester 被引量:1
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作者 Ahmed Zaky Sayed Mahmoud Sayed Aboul-Fetouh Hesham Sayed Nassar 《Journal of Chemistry and Chemical Engineering》 2011年第2期150-158,共9页
The synthesis of some new diazo disperse dyes containing a pyrazol-5-one was described. The structures of the new products have been deduced from elemental analysis and spectral dada such as UV-Vis absorption, IR, ^1H... The synthesis of some new diazo disperse dyes containing a pyrazol-5-one was described. The structures of the new products have been deduced from elemental analysis and spectral dada such as UV-Vis absorption, IR, ^1H NMR, and MS spectroscopy. These dyestuffs gave satisfactory results when applied as disperse dyes to polyester fabric. The dyeing properties such as light fasmess, washing fastness and exhaustion studies have been investigated. 展开更多
关键词 Pyrazolin-5-one disperse dyes disazo dyes DYEING EXHAUSTION FASTNESS
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Study of oxidization of coal–pitch by O_3 被引量:2
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作者 Wang Yaoling Chen Sishun +1 位作者 Ding Mingjie Xu Zhan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期677-681,共5页
For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studi... For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds. 展开更多
关键词 Study Coal-pitch Ozone oxidation Depolymerization
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Optimizing the nickel boride layer thickness in a spectroelectrochemical ATR-FTIR thin-film flow cell applied in glycerol oxidation 被引量:2
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作者 Steffen Cychy Sebastian Lechler +7 位作者 Zijian Huang Michael Braun Ann Cathrin Brix Peter Blümler Corina Andronescu Friederike Schmid Wolfgang Schuhmann Martin Muhler 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第12期2206-2215,共10页
The influence of the drop-casted nickel boride catalyst loading on glassy carbon electrodes was investigated in a spectroelectrochemical ATR-FTIR thin-film flow cell applied in alkaline glycerol electrooxidation.The c... The influence of the drop-casted nickel boride catalyst loading on glassy carbon electrodes was investigated in a spectroelectrochemical ATR-FTIR thin-film flow cell applied in alkaline glycerol electrooxidation.The continuously operated radial flow cell consisted of a borehole electrode positioned 50μm above an internal reflection element enabling operando FTIR spectroscopy.It is identified as a suitable tool for facile and reproducible screening of electrocatalysts under well-defined conditions,additionally providing access to the selectivities in complex reaction networks such as glycerol oxidation.The fast product identification by ATR-IR spectroscopy was validated by the more time-consuming quantitative HPLC analysis of the pumped electrolyte.High degrees of glycerol conversion were achieved under the applied laminar flow conditions using 0.1 M glycerol and 1 M KOH in water and a flow rate of 5μL min^(–1).Conversion and selectivity were found to depend on the catalyst loading,which determined the catalyst layer thickness and roughness.The highest loading of 210μg cm^(–2)resulted in 73%conversion and a higher formate selectivity of almost 80%,which is ascribed to longer residence times in rougher films favoring readsorption and C–C bond scission.The lowest loading of 13μg cm^(–2)was sufficient to reach 63%conversion,a lower formate selectivity of 60%,and,correspondingly,higher selectivities of C_(2)species such as glycolate amounting to 8%.Thus,only low catalyst loadings resulting in very thin films in the fewμm thickness range are suitable for reliable catalyst screening. 展开更多
关键词 Catalyst layer thicknes ELECTROCATALYST Nickel boride Operando ATR-IR High performance liquid CHROMATOGRAPHY Flow cell Thin film Anodic glycerol oxidation
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Preparation, characterization, and antifungal activity of hymexazol-linked chitosan derivatives
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作者 李俨 秦玉坤 +2 位作者 刘松 李鹏程 邢荣娥 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1079-1085,共7页
In this study, three hymexazol-linked chitosan derivatives (HML-CS) were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performa... In this study, three hymexazol-linked chitosan derivatives (HML-CS) were synthesized and their structures confirmed by Fourier transform infrared and elemental analysis. Linkage ratios were measured by high performance liquid chromatography. The derivatives' antifungal activity against the plant pathogenic fimgi Rhizoctonia solani CGMCC 3.28 and Gibberella zeae CGMCC 3.42 were investigated at concentrations of 100, 200, and 400 mg/L. These HML-CS derivatives exhibited stronger antifungal activity than CS alone. HML-CS-1 showed the best antifizngal activity against G. zeae, whose antifimgal index was 65.9% at 400 mg/L, and also showed the best antifungal activity against R. solani, whose antifimgal index was 52.7% at 400 mg/L. This conjugation of CS and HML suggested the presence of synergistic effects between the moieties and indicated that these derivatives possessed great potential as novel fungicides and require further research for the development of applications in crop protection. 展开更多
关键词 antifungal activity CHITOSAN linked copolymer HYMEXAZOL
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Optimization of Yield and Chemical Properties of Agar Extracted from Melanothamnus Somalensis from Oman Sea
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作者 Zainab Mohammed Al-Nahdi Ahmed Al-Alawi +1 位作者 Insaaf Al-Marhobi Ali Al-Zefiti 《Journal of Environmental Science and Engineering(B)》 2015年第6期302-314,共13页
The red seaweed Melanothamnus somalensis was investigated as potential economic source of agar. The effect of different conditions of alkali pre-treatment on chemical properties of agar was evaluated. Agar was extract... The red seaweed Melanothamnus somalensis was investigated as potential economic source of agar. The effect of different conditions of alkali pre-treatment on chemical properties of agar was evaluated. Agar was extracted by various concentrations of NaOH (4%, 6% and 8%) and heated at different temperatures (70 ℃, 75 ℃ and 80 ℃) for different durations (2 h, 2.75 h and 3.5 h). The yields-molecular weight (Mw) and sulfate contents of extracted agar were analysed and characterized by FTIR spectroscopy. The yield was significantly increased at these treatments from 23.29% to 30.86%. Mw studied by HPLC ranged from (.12.45 ± 0.21) × 10^5 to (8.60 ± 2.40) × 10^5 Da. FTIR bands show sulfate groups in C4 and C6 ofgalactose and no sulfate group were found on both C2 of galactose and C2 of 3,6-anhydrogalactose. All treatments showed a high sulfate content that ranged from 5.4% to 10.1%. These properties were found to be significantly affected by the alkali pre-treatment concentration (p 〈 0.05). In conclusion, agar extracted in this study was considered acceptable for industrial application and the optimal conditions for extraction were found to be at 6% NaOH at 70 ℃ for 2 hours. 展开更多
关键词 SEAWEED Melanothamnus somalensis agarophytes agar extraction alkali pre-treatment FTIR.
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Nickel Catalyzed High-Pressure Hydrothermal Processing of Biomass for H2 Production
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作者 R. Tungal R.V. Shende L.P. Christopher 《Journal of Energy and Power Engineering》 2011年第6期504-514,共11页
In this study, high-pressure hydrothermal processing of different biomass sources and products, which include cellulose, xylan, lignin, pine wood, paper waste, and waste lignin was performed at 200-275 ℃ in presence ... In this study, high-pressure hydrothermal processing of different biomass sources and products, which include cellulose, xylan, lignin, pine wood, paper waste, and waste lignin was performed at 200-275 ℃ in presence of NiSO4 catalyst. Biomass slurry was prepared in distilled water containing NiSO4, loaded in a high-temperature high-pressure reactor and heated to different temperatures. The reaction was continued for 120 min and during the reaction gas samples were withdrawn and analyzed using Chrompack capillary column on the gas chromatograph equipped with thermal conductivity detector. The analysis of gas samples revealed the presence of H2, CO2, CO, and CH4 gases. Increase in catalyst concentration from 3 wt% to 10 wt% has significantly increased the H2 generation. Absence of catalyst, however, generated almost negligible amount of H2. Among the biomass sources and products investigated here, xylan has yielded maximum amount of H2. The liquid samples were analyzed by high-performance liquid chromatography (HPLC) and Fourier transform infrared (FTIR) spectroscopy which revealed the presence of sugars along with the other intermediates. 展开更多
关键词 BIOMASS subcritical water NiSO4 hydrogen.
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用声音解析共产党人精神谱系——《探寻中国共产党人精神谱系》创作感悟
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作者 曾致 《中国广播电视学刊》 CSSCI 北大核心 2021年第12期75-76,121,共3页
红色故事震撼人心,革命精神感天动地。"红色光谱——探寻中国共产党人精神谱系"系列音频节目主题立意深,故事切口小,评论有力量,播讲有温度,以"评论+专家点评+听众互动"的生动形式推动红色精神的大众化传播,收到良... 红色故事震撼人心,革命精神感天动地。"红色光谱——探寻中国共产党人精神谱系"系列音频节目主题立意深,故事切口小,评论有力量,播讲有温度,以"评论+专家点评+听众互动"的生动形式推动红色精神的大众化传播,收到良好的社会效益。当下,广大播音员主持人应当认真学习伟大建党精神,感悟中国共产党人的精神谱系,在人生观、道德观、价值观、审美观和艺术观上,旗帜鲜明地赓续红色血脉,唱响时代主旋律。 展开更多
关键词 《红色光谱》 播音创作 时代价值
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Red emitting tungsto-molybdate phosphor for near-ultraviolet light-emitting diodes-based solid-state lighting 被引量:2
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作者 XIE An YANG WeiYi ZHANG MinShu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第7期1229-1234,共6页
A series of novel red tungsto-molybdate phosphors, LiEul-xSmx(WO4)0.5(MoO4)1.5 (x = 0, 0.25%, 0.50%, 0.75%, 1.00%, 2.00% 4.00%, 6.00%, 8.00% and 10.00%), were synthesized using conventional solid state reaction ... A series of novel red tungsto-molybdate phosphors, LiEul-xSmx(WO4)0.5(MoO4)1.5 (x = 0, 0.25%, 0.50%, 0.75%, 1.00%, 2.00% 4.00%, 6.00%, 8.00% and 10.00%), were synthesized using conventional solid state reaction methods. The experimental re- sults indicate that the introduction of Sm^3+ changes neither the crystal structure nor the shape and position of the emission spectra. However, it extends the excitation region at 400 nm and enhances the emission at 615 nm. The reason for the im- provement of red emission of Eu^3+ by the introduction of Sm^3+ and the energy transfer mechanism from Sm^3+ to Eu^3+ was in- vestigated in detail. 展开更多
关键词 tungsto-molybdate red emitting phosphors white LEDs energy transfer
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