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1.
《Fuel》2005,84(7-8):973-991
The phase-mineral and chemical composition of heavy concentrates (HCc) and improved fly ash residues (IFAs) recovered from five fly ashes (FAs) produced in four large Spanish thermo-electric power stations was characterized. The HCs were separated by sink-float separation in bromoform, while the IFAs are residues after the isolation of ceramic cenosphere, salt, magnetic, char and heavy concentrates. The HCs recovered are in the range 0.02–0.28% and their phase-mineral composition (in decreasing order of significance) commonly includes aluminosilicate glass, hematite, magnetite, larnite, quartz, periclase, mullite, corundum, lime, char, melilite, rutile, plagioclase, wollastonite, ferrian spinel, and anhydrite. Numerous accessory minerals of Ba, Ce, Cl, Cr, Cu, F, Fe, La, Mn, P, Pb, Th, Ti, Y, and Zr, are also typical components of HCs. These fractions are enriched in As, Ca, Cr, Cu, Gd, Mg, Mn, Mo, Fe, Ni, Pb, S, Se, Ti, V, Zn, and Zr in comparison with the FAs. The IFAs isolated are in the range 71.5–97.1% and their phase-mineral composition (in decresing order of significance) normally includes aluminosilicate glass, mullite, quartz, char, kaolinite, plagioclase, cristobalite, wollastonite, hematite, anhydrite, K-feldspar, melilite, and corundum. The contents of most elements in IFAs are similar to FAs as Ag, Ba, Cl, Cs, Ge, Mo, S, Sb, and Sc are significantly depleted in these residues. The IFAs have an improved composition in comparison with the FAs because they are: more homogeneous and finer-grained products; abundant in pozzolan and inert constituents; and depleted in harmful components. Some genetic features, properties, possible environmental concern, and potential utilization directions related to the HCs and IFAs are described. A basis for the advanced, multicomponent, wasteless, and environmentally safety utilization of various FAs is also discussed.  相似文献   

2.
应用ICP-MS同时测定矿泉水中22种微量金属   总被引:1,自引:0,他引:1  
研究结果表明应用ICP-MS可以同时测定饮用天然矿泉水中的Li、Be、B、Al、Ti、V、Cr、Mn、Co、Ni、Cu、Zn、Ge、As、Se、Sr、Mo、Ag、Cd、Sb、Ba、Pb、等微量金属元素.ICP-MS法具有快速、准确、处理简单、干扰少等优点.  相似文献   

3.
微波消解-ICP-OES法测定黑芝麻中的18种矿质元素   总被引:1,自引:0,他引:1  
曹蕾  耿薇  魏永生 《应用化工》2012,41(5):910-913
采用HNO3/H2O2湿法微波消解制样,利用全谱直读电感耦合等离子原子发射光谱法(ICP-OES),全面详细地分析测定了黑芝麻中的矿质元素,共检出Ca、P、S、Mg、K、Al、Si、Fe、Na、Zn、Se、Sr、Cu、Mn、Ba、B、Ti、Cr等18种矿质元素,RSD值在1.21%~10.1%,其中13种元素在5%以内。黑芝麻中所含人体常量元素Ca、P、S、Mg、K、Na等的质量分数分别为1.79%,1.08%,0.59%,0.43%,0.41%和0.009 1%;微量元素Fe、Zn、Se、Cu、Mn、B、Cr、Sr、Si、Al等的含量分别为18.6,4.55,3.87,1.74,1.62,0.91,3.21,78.8,125.8 mg/100 g,未检出Pb、Hg、Cd、As以及Ni、Co、Mo等元素。  相似文献   

4.
本研究采用邻苯二酚、溴代正戊烷和乙酰氯为原料合成了以苯并菲为基元的盘状液晶化合物2,6,10-三乙酯基-3,7,11-三戊氧基苯并菲,化合物的结构采用核磁手段1HNMR进行鉴定。采用偏光显微镜POM和DSC手段对该种化合物的相行为进行了研究,并且与合成过程中的中间体2,3,6,7,10,11-六戊氧基苯并菲的相行为进行了比较。  相似文献   

5.
Based on the available toxicity data and the concentrations of polycyclic aromatic hydrocarbons (PAHs) in 16 surface sediments from upper reach of Huaihe River, overlapping areas of probability density curves and margin of safety (MOS10) were used to estimate the ecological risk of eight PAHs to aquatic organisms. The results indicated that the overlapping areas of Pyr, Nap, Fla, Ant, Phe, Ace, BaP, and Flu were 0.38, 0.29, 0.16, 0.11, 0.07, 0.03, 0.03, and 0.01, respectively. The risk of Pyr was the highest while that of Flu was the lowest. The overlapping area of ΣPAH8 was 0.72, higher than that of any individual PAHs due to their joint effect. The calculated MOS10 for Nap, Ace, Flu, Phe, Ant, Fla, Pyr, and BaP were 6.86, 5.42, 19.0, 2.72, 0.93, 0.75, 0.03, and 63.0, respectively. The probabilities of Nap, Ace, Flu, Phe, and BaP surpassing the 10th percentile value of the toxicity data were 0.07%, 0.30%, 0.05%, 1.97%, and 0.01%, respectively, suggesting minimal risk to aquatic organisms. However, the probabilities of Ant, Fla, and Pyr exceeding this value were 11.3%, 12.9%, and 64.8%, indicating potential risks. Among the individual PAHs, the ecological risk from Pyr was the highest, followed by Fla, Ant, Phe, Ace, Nap, Flu, and BaP. Additionally, the combined ecological risk of ΣPAH8 in the upper reach of Huaihe River was significantly higher than that of any individual PAH alone, which the probabilities of ∑PAH8 in excess of the 10th percentile of the toxicity data were 99.4%.  相似文献   

6.
芦丁及其衍生物具有广泛的药理活性。芦丁具有完整的大盯键共轭体系,强配位氧原子与合适的空间构型,可与金属离子螯合成稳定的环状配合物。研究表明:这些配合物有些具有明显的生物活性,有些药理作用显著。到目前为止,国内外共合成了31种芦丁金属配合物,其中主族元素有5个:Mg、Al、Ga、Sn和Bi;副族元素有12个:Cr、Mn、Fe、Co、Ni、Cu、Zn、Y、Mo、Cd、Pt和Au;稀土元素有14个:La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu等。  相似文献   

7.
抗菌防腐剂(Ⅰ)—抗菌防腐剂的历史、定义与分类   总被引:6,自引:0,他引:6  
简要回顾了抗菌防腐剂的发展历程,进一步明确了杀菌剂,抑菌剂,抗菌剂,防腐剂,防霉剂,消毒剂,杀生剂,保鲜剂,抗生素的概念。同时,结合抗菌防腐剂的发展在对抗菌防腐剂按无机物,有机物和天然物分类的基础上,进一步又按化学结构和官能团将抗菌剂分为有机金属,有机卤代物,醇,酚,醚,醛,酮,醌,酸,酯,含氮类,含硫类,有机磷,有机砷类以及杂环类等。  相似文献   

8.
Since the last decade, electrospinning is garnering more attention in the scientific research community, industries, applications like sensing (glucose, H2O2, dopamine, ascorbic acid, uric acid, neurotransmitter, etc.), biomedical applications (wound dressing, wound healing, skin, nerve, bone tissue engineering, and drug delivery systems), water treatment, energy harvesting, and storage applications. This review paper provides a brief overview of the electrospinning method, history of the electrospinning, factors affecting the electrospun nanofibers, and their morphology with different materials and composites (metals, metal oxides, 2D material, polymers and copolymers, carbon-based materials, etc.) used in the electrospinning technique with optical spinning parameters. Moreover, this paper deliberates the application of electrospun nanofibers and fibrous mats for sensing (electrochemical, optical, fluorescence, colorimetric, mechanical, photoelectric, mass sensitive change, resistive, ultrasensitive, etc.) in most illustrative representations. In the end, the challenges, opportunities of the electrospun nanofibers, and new direction for future progress are also discussed.  相似文献   

9.
合成环己酮乙二醇缩酮的催化剂研究进展   总被引:3,自引:0,他引:3  
文瑞明  游沛清  俞善信 《化工进展》2007,26(11):1587-1595
评述了近年来国内采用甲烷磺酸盐、对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、磺化聚氯乙烯、六水三氯化铁、二水氯化亚锡、五水四氯化锡、四水氯化锰、硫酸铜、水合硫酸铁、十二水合硫酸铁铵、硫酸钛、四水硫酸锆、氯化锆、四水硫酸高铈、水合硝酸镧、活性炭固载硫酸镧、铌酸、树脂固载Lewis酸、壳聚糖硫酸盐、一水硫酸氢钠、碘、磷酸二氢钠、固体超强酸、杂多酸、分子筛和维生素C等固体酸催化合成环己酮乙二醇缩酮的实验结果。研究结果表明,固体酸能够代替硫酸作为合成环己酮乙二醇缩酮反应的催化剂。  相似文献   

10.
氯碱下游产品建设投资分析(续2)   总被引:2,自引:1,他引:1  
介绍了20种氯碱下游产品--氯甲苯、氯乙酸、环氧氯丙烷、氯化苄、环氧丙烷、聚偏氯乙烯树脂、氯化聚氯乙烯树脂、氯化聚乙烯、甲基氯硅烷、三氯氢硅、氯化法钛白粉、三氯化磷、4,4'-二苯基甲烷二异氰酸酯、1,4-丁二醇、苯胺、环己酮、气相法白炭黑、甲基异丁基酮、对氨基苯酚、水合肼的市场前景、技术来源与建设投资.  相似文献   

11.
廖军敏 《广州化工》2006,34(4):64-66
感光级硝酸银样品经一系列的化学处理后,上清液采用石墨炉原子吸收分光光度法测定其中Bi,Cd,Cr,Cu,Fe,Mn,Ni,Pb,Sb,Sn,Te,Se,Zn元素的含量,本方法测定Bi,Cd,Cr,Cu,Fe,Mn,Ni,Pb,Sb,Sn,Te,Se,Zn各元素均能得到良好的标准曲线,即r=0.99~1;Cu、Cr、Ni、Sb、Sn、Mn、Te、Se的回收率较好,一般可达到95%~110%,Zn、Bi、Cd、Pb的回收率较低,经常只有50%~60%。  相似文献   

12.
ABSTRACT

The extraction of microquantities of Ca, Sr, Ba, Sc, Mn, Co, Cu, Zn, Ga, Cd, In, Pb, Bi, Zr, Hf, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, and U from HNO3 solutions by (diphenylphosphinylmethyl)phenylphosphinic acid in organic diluents has been studied.

The effect of HNO3 concentration in the aqueous phase and that of the extractant in the organic phase on the metal extraction are considered. (Diphenylphosphinylmethyl)phenylphosphinic acid possesses an extraordinary affinity for actinides and rare-earth elements. The extractive efficiency and selectivity of this compound toward rare-earth metal ions are compared with those of some multifunctional acidic and neutral organophosphorus extractants.  相似文献   

13.
采用HNO3/H2O2湿法微波消解制样,采用全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),分析测定了苦荞麦中的矿物元素,共检出P、S、K、Mg、Ca、Si、Al、Fe、Na、Zn、Mn、B、Cu、Se、Ti、Cr、Ba、Sr等18种矿物元素。分析结果的RSD值在0.45%~9.09%之间,其中15种元素在5%以内。苦荞麦中所含P、S、K、Mg、Ca、Na等常量元素的质量分数分别为0.21%、0.21%、0.17%、0.098%、0.019%、0.0017%;微量元素Fe、Zn、Cu、Se、Cr、Si、Mn、B、Ti、Ba、Sr、Al等的含量(mg.kg-1)分别为37.4、16.5、3.67、1.38、0.44、121.6、6.90、4.88、0.63、0.22、0.12、49.9。  相似文献   

14.
梁诚 《氯碱工业》2009,45(1):24-27
介绍了20种氯碱下游产品——氯甲苯、氯乙酸、环氧氯丙烷、氯化苄、环氧丙烷、聚偏氯乙烯树脂、氯化聚氯乙烯树脂、氯化聚乙烯、甲基氯硅烷、三氯氢硅、氯化法钛白粉、三氯化磷、4,4’-二苯基甲烷二异氰酸酯、1,4-丁二醇、苯胺、环己酮、气相法白炭黑、甲基异丁基酮、对氨基苯酚、水合肼的市场前景、技术来源与建设投资。  相似文献   

15.
Psychotropics (antipsychotics, mood stabilizers, antidepressants, anxiolytics, etc.) are commonly prescribed to treat Huntington’s disease (HD). In HD preclinical models, while no psychotropic has convincingly affected huntingtin gene, HD modifying gene, or huntingtin protein expression, psychotropic neuroprotective effects include upregulated huntingtin autophagy (lithium), histone acetylation (lithium, valproate, lamotrigine), miR-222 (lithium-plus-valproate), mitochondrial protection (haloperidol, trifluoperazine, imipramine, desipramine, nortriptyline, maprotiline, trazodone, sertraline, venlafaxine, melatonin), neurogenesis (lithium, valproate, fluoxetine, sertraline), and BDNF (lithium, valproate, sertraline) and downregulated AP-1 DNA binding (lithium), p53 (lithium), huntingtin aggregation (antipsychotics, lithium), and apoptosis (trifluoperazine, loxapine, lithium, desipramine, nortriptyline, maprotiline, cyproheptadine, melatonin). In HD live mouse models, delayed disease onset (nortriptyline, melatonin), striatal preservation (haloperidol, tetrabenazine, lithium, sertraline), memory preservation (imipramine, trazodone, fluoxetine, sertraline, venlafaxine), motor improvement (tetrabenazine, lithium, valproate, imipramine, nortriptyline, trazodone, sertraline, venlafaxine), and extended survival (lithium, valproate, sertraline, melatonin) have been documented. Upregulated CREB binding protein (CBP; valproate, dextromethorphan) and downregulated histone deacetylase (HDAC; valproate) await demonstration in HD models. Most preclinical findings await replication and their limitations are reviewed. The most promising findings involve replicated striatal neuroprotection and phenotypic disease modification in transgenic mice for tetrabenazine and for sertraline. Clinical data consist of an uncontrolled lithium case series (n = 3) suggesting non-progression and a primarily negative double-blind, placebo-controlled clinical trial of lamotrigine.  相似文献   

16.
高分子材料的老化研究   总被引:3,自引:0,他引:3  
周勇 《国外塑料》2012,(1):35-41
本文介绍了由高分子材料老化引起的外观、物理性能、力学性能、电性能的变化;分析了引起高分子材料老化的内在因素和外在因素,例如化学结构、物理形态、立体规整性、分子量及其分布情况、金属杂质、温度、湿度、氧气、光照、化学介质、生物等;阐述了自然环境老化实验、人工加速老化实验、耐候性实验、热老化实验、湿热老化实验、臭氧老化实验、盐雾腐蚀实验、耐寒性实验、抗霉实验等老化评价方法和物理性能、力学性能、微观分析、耐久性能以及系统分析技术等老化性能评价指标;并对热老化预防措施、湿热老化预防措施、氧老化预防措施、光老化预防措施以及生物老化预防措施进行了展望。  相似文献   

17.
松油醇制备中副产物红油化学组成的研究   总被引:4,自引:0,他引:4  
朱凯  朱新宝  毛连山 《现代化工》2004,24(11):33-35
用气相色谱-质谱联用分析(GC-MS)对松油醇副产物红油化学组成进行了研究,结果共鉴定出30个化学成分,主要成分有蒎烯、莰烯、对伞花烃、松油烯、柠檬烯、桉叶油素、松油烯醇、小茴香醇、松油醇、龙脑、十氢-4,8,8-三甲基-9-亚甲基-1,4-亚甲基奥、石竹烯等化合物,其中的小茴香醇、十氢-1,5,5,8a-四甲基-1,2,4-亚甲基奥、1,3,4,5,6,7-六氢-1,1,5,5-四甲基-,(2S)-2H-2,4a-亚甲基萘、十氢-4,8,8-三甲基-9-亚甲基-1,4-亚甲基奥、alpha-panasinsen化合物之前未见出之红油的报道。提出采用真空分馏、化学加成、低温结晶和硼酸酯化方法进行分离、提纯,以便得到蒎烯、莰烯、桉叶油素、龙脑、异龙脑、小茴香醇等化合物。  相似文献   

18.
枳实中有效成分的综合提取工艺研究   总被引:1,自引:0,他引:1  
以川产枳实为原料,对其中有效成分辛弗林、橙皮苷、柚皮苷、新橙皮苷、柠檬苦素、果胶、挥发油、枳实黄酮、枳实高蛋白饲料等进行了清洁化同步高效提取分离,得到一条清洁化同步高效提取工艺路线。辛弗林、橙皮苷、柚皮苷、新橙皮苷、柠檬苦素、果胶、挥发油、枳实黄酮、枳实高蛋白饲料的得率分别为0.5%、25.2%、3.2%、1.1%、0.1%、15.2%、1.4%、10.8%、62%,质量分数分别为98.4%、96.4%、99.4%、98.8%、99.2%、93%、75%、80%、25.2%。  相似文献   

19.
The contamination by 16 polycyclic aromatic hydrocarbons (PAHs) in surface soils, sampled at a 0-5 cm depth in the urban areas of Tallinn, Helsinki, Vilnius, Chicago, London is reported. All samples were analyzed using the same protocol. The median concentrations ( w g/kg) were found to be 117, 539, 127, 3,263, 1,728 for pyrene; 62, 236, 43, 1,634, 1,652 for benzo[ a ]pyrene; 86, 304, 92, 2,295, 2,068 for benzo[ a ]pyrene toxic equivalents, calculated using the benzo[ a ]pyrene toxic equivalency factors; 467, 1,471, 392, 8,981, 6,837 for a total of seven probable human carcinogenic PAHs: benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, indeno[1,2,3- cd ]pyrene; 911, 2,941, 672, 16,183, 13,718 for the total of 16 PAHs, recommended by the U.S. Environmental Protection Agency: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, benzo[ ghi ]perylene, indeno[1,2,3- cd ]pyrene in Tallinn ( n = 3), Helsinki ( n = 3), Vilnius ( n = 15), Chicago ( n = 4), London ( n = 3), respectively. The size of the population is a statistically significant factor in urban soil contamination by high-molecular-mass PAHs.  相似文献   

20.
Shifeng Dai  Dexin Han 《Fuel》2006,85(4):456-464
Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 μg/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation.  相似文献   

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