石墨烯修饰玻碳电极在对苯二酚存在下选择性测定米吐尔

制备了石墨烯修饰玻碳电极(GN/GCE)。 在0.5 mol/L HAc-NaAc(pH=4.8)缓冲溶液中,用循环伏安法(CV)和方波伏安法(SWV)研究了米吐尔在修饰电极上的电化学行为,建立了测定米吐尔的新方法。 研究表明,米吐尔在GN/GCE上的氧化、还原峰电势差比其在裸玻碳电极(GCE)上的小,峰电流显著增加,说明GN/GCE对米吐尔有电催化作用;共存物对苯二酚干扰米吐尔的测定,通过方波伏安法可以消除其干扰。 在方波伏安曲线上,米吐尔的还原峰电流与其浓度在8.0×10^-8~5.0×10^-5 mol/L范围内呈线性关系,检出限为2.0×10^-8 mol/L。 该法可用于照相显影废液中米吐尔的测定。     

米吐尔在离子液体修饰碳糊电极上的电化学行为及其测定

用离子液体1-庚基-3-甲基咪唑六氟磷酸([HMIM][PF6])作修饰剂制备了离子液体修饰碳糊电极(IL/CPE).在0.5 mol/L HAc-NaAc(pH=4.8)缓冲溶液中,采用循环伏安法(CV)和方波伏安法(SWV)研究了米吐尔在该修饰电极上的电化学行为,建立了测定米吐尔的新方法.研究表明,米吐尔在IL/CPE上的氧化、还原峰电位差比其在裸碳糊电极(CPE)上的小,而峰电流却显著增加,说明IL/CPE对米吐尔有电催化作用;共存物对苯二酚干扰米吐尔的测定,通过方波伏安法可以消除其干扰.在方波伏安曲线上,米吐尔的还原峰电流与其浓度在1.0×10-7 ～2.0×10-5 mol/L范围内呈线性关系,检出限为3.0×10-8 mol/L.该法可用于照相废液中米吐尔的测定.     

芦丁在纳米金修饰玻碳电极上的电化学行为及其测定

采用循环伏安法将纳米金电沉积于玻碳电极表面,制备了纳米金修饰玻碳电极(NG/GCE).在pH3.29的Britton-Robinson(B-R)缓冲溶液中,用循环伏安法研究了芦丁在NG/GCE上的电化学行为.结果表明,NG/GCE对芦丁的氧化还原反应有良好的电催化作用.用方波伏安法测得芦丁的还原峰电流与其浓度在2.0×10-8～2.0×10-6mol/L范围内呈线性关系,检出限为1.0×10-8mol/L(S/N=3).     

铂/多壁碳纳米管修饰玻碳电极用于微分脉冲伏安法测定左旋多巴

采用微波辅助加热多元醇技术制备了载铂多壁碳纳米管复合材料,并将该复合材料分散在N,N′-二甲基甲酰胺溶液中得到悬浮液,取14μL悬浮液滴涂在玻碳电极表面,制备铂/多壁碳纳米管修饰电极(Pt/MWCNT′s/GCE)。循环伏安法研究了在0.05mol·L~(-1)硫酸支持电解质中,在0.30～0.70V(vs.SCE)电位范围内,左旋多巴在修饰电极上的电化学行为,结果表明:左旋多巴在Pt/MWCNT′s/GCE上于电位0.548V处可见明显的氧化峰,且氧化峰电流显著高于在MWCNT′s/GCE和裸玻碳电极上的氧化峰电流。提出了用微分脉冲伏安法测定左旋多巴的方法。左旋多巴的浓度在8.0×10~(-6)～2.0×10~(-1)mol·L~(-1)范围内与其氧化峰电流呈线性关系,检出限(3S/N)为1.9×10~(-6)mol·L~(-1),平均回收率为102.8%。     

对硫磷在纳米氧化铝薄膜修饰电极上的电化学行为及其测定

制备了纳米氧化铝修饰玻碳电极(nano-Al2O3/GCE/CME),用循环伏安法(CV)、线性扫描伏安法(LSV)研究了对硫磷(TP)在nano-Al2O3/GCE/CME上的电化学行为.实验表明,该修饰电极与裸电极相比能显著提高TP的氧化还原峰电流并降低其氧化峰电位.在0.1 mol/L HAc-NaAc缓冲溶液(pH =5)中,TP在该修饰电极上产生1个不可逆的还原峰( Epc1=-0.567 V)和1对可逆氧化还原峰( Epa2=0.018 V和Epc2=-0.008 V) ,氧化峰电流与TP的浓度在2.5×10-9～1.0×10-7 mol/L和1.0×10-7～1.0×10-5 mol/L范围内具有良好的线性关系,回归方程分别为: ip(μA)=0.2529+4.201C(μmol/L), r=0.9984和ip(μA)=0.6752+0.3181C(μmol/L), r=0.9946.开路富集30 s后,检出限为1.0 ×10-9 mol/L(S/N=3).在1.0×10-5 mol/L TP试液中连续测定10次,其RSD为3.8%.用此方法测定了蔬菜中TP的含量,回收率为95. 6%～100.5% ,结果满意.     

嗪草酮在玻碳电极上的伏安行为及测定

用循环伏安法及微分脉冲阴极溶出伏安法,在玻碳电极(GCE)上研究了嗪草酮在不同底液中的伏安特性,发现在B-R(Britton-Robinson)电解质溶液(pH2)中于-0.524V(vs.SCE)左右产生1个尖锐的阴极还原峰。嗪草酮的浓度在1.0×10-6~1.0×10-4mol/L范围内与峰电流呈良好的线性关系(r=0.9987)。对其反应机理作了初步探讨。     

普鲁士蓝-多壁碳纳米管复合材料修饰电极测定过氧化氢

利用电化学方法在多壁碳纳米管(MWCNT)修饰的玻碳电极表面聚合一层普鲁士蓝(PB)(PB/MWCNT/GCE),制备了一种新型的过氧化氢(H2O2)传感器。研究了该传感器对H2O2的电催化作用。讨论了支持电解质种类、酸度、修饰层厚度、电位和扫速等对H2O2响应的影响。研究表明,该传感器在以1.0mol/L KCl为支持电解质的磷酸盐溶液(pH=2.0)中,对H2O2具有明显的催化效应,测定的线性范围变宽,在2.9×10-6~8.8×10-2mol/L范围内还原峰电流与H2O2的浓度呈良好的线性关系,相关系数为0.9949;检出限为1.4×10-6mol/L。该电极用于医用消毒水中H2O2的测定,结果令人满意。     

盐酸阿霉素在玻碳电极上的电化学行为研究及分析应用

采用线性扫描伏安法和循环伏安法研究了盐酸阿霉素在玻碳电极上的电化学行为及电极反应机理,优化了测定盐酸阿霉素的各实验参数。结果表明,在0.01 mol/L的HCl溶液中,盐酸阿霉素在-0.40 V处出现(vs.SCE)一灵敏的还原峰,峰电流与其溶液浓度在5.0×10-8~1.0×10-6mol/L(r=0.999)和1.0×10-6~1.0×10-5mol/L(r=0.998)范围内呈良好的线性关系,检出限为1.0×10-8mol/L。并用循环伏安法研究了盐酸阿霉素的峰电流性质,发现电极反应属于准可逆过程,出现一对灵敏的氧化还原峰,体系属准可逆吸附波。利用盐酸阿霉素在玻碳电极的电化学行为建立的分析方法可用于盐酸阿霉素的质量监控及药代动力学研究。     

咖啡酸在多壁碳纳米管修饰玻碳电极上的电化学行为及其测定

制备了多壁碳纳米管(MWNT)修饰玻碳电极,并研究了咖啡酸在该电极上的电化学行为及其测定方法,与裸玻碳电极(GCE)相比,MWNT膜修饰电极(MWNT/GCE)能显著提高咖啡酸的氧化峰电流.在pH=3.29的B-R缓冲溶液中,咖啡酸在MWNT/GCE电极上出现1对准可逆的氧化还原峰,Epa=0.47 V,Epc=0.32 V,峰电流与其浓度在5.0×10-7～2.0×10-5 mol/L范围内成线性关系,检出限为5.0×10-7mol/L.实际样品测定的相对标准偏差(RSD)为0.82％(n=5),平均回收率为100.7％.MWNT膜对咖啡酸的电化学氧化有明显的催化作用.该法是一种快捷、可靠、灵敏的检测方法,可以用于咖啡酸含量的测定.     

用多壁碳纳米管修饰玻碳电极为工作电极循环伏安法测定辛硫磷

将多壁碳纳米管(MWCNT′s)置于硝酸-硫酸(1+1)溶液中回流6 h使之净化及功能化。取MWCNT′s 5 mg置于超纯水10 mL中经超声振荡20 min制得其悬浮液,取悬浮液10μL滴加在玻碳电极(GCE)表面,经自然干燥后即得用MWCNT′s修饰的玻碳电极(MWCNT′s/GCE)。基于此修饰电极对辛硫磷的催化还原反应,提出了蔬菜中辛硫磷的循环伏安测定法,在pH 4的乙酸盐支持电解质溶液中,在电位0.78 V(对SCE)处可见明显的还原峰,且其峰电流值与辛硫磷浓度在5.0×10-8~1.0×10-6mol.L-1之间呈线性关系。应用此法分析了两件蔬菜样品,并以此试样为基体加入标准溶液对方法进行回收及精密度试验,测得其回收率的平均值和相对标准偏差(n=5)分别依次为100.3%,96.5%及3.7%,3.2%。     

Adsorption of Carbon Dioxide on Activated Carbon

The adsorption of CO2 on a raw activated carbon A and three modified activated carbon samples B, C, and D at temperatures ranging from 303 to 333 K and the thermodynamics of adsorption have been investigated using a vacuum adsorption apparatus in order to obtain more information about the effect of CO2 on removal of organic sulfur-containing compounds in industrial gases. The active ingredients impregnated in the carbon samples show significant influence on the adsorption for CO2 and its volumes adsorbed on modified carbon samples B, C, and D are all larger than that on the raw carbon sample A. On the other hand, the physical parameters such as surface area, pore volume, and micropore volume of carbon samples show no influence on the adsorbed amount of CO2. The Dubinin-Radushkevich (D-R) equation was the best model for fitting the adsorption data on carbon samples A and B, while the Preundlich equation was the best fit for the adsorption on carbon samples C and D. The isosteric heats of adsorption on carbon samples A, B, C, and D derived from the adsorption isotherms using the Clapeyron equation decreased slightly increasing surface loading. The heat of adsorption lay between 10.5 and 28.4 kJ/mol, with the carbon sample D having the highest value at all surface coverages that were studied. The observed entropy change associated with the adsorption for the carbon samples A, B, and C (above the surface coverage of 7 ml/g) was lower than the theoretical value for mobile adsorption. However, it was higher than the theoretical value for mobile adsorption but lower than the theoretical value for localized adsorption for carbon sample D.     

The Colloidal Stabilization of Carbon with Carbon: Carbon Nanobubbles as both Dispersant and Glue for Carbon Nanotubes

The superior physical properties of carbon nanotubes (CNTs) have led to their broad application. Intrinsically, CNTs tend to agglomerate from hydrophobic interactions, which is highly undesirable for solution processing and device fabrication. Commonly, a stabilizer consisting of organic surfactants or polymers is used to disperse CNTs. Recently, we synthesized nitrogen‐doped carbon hollow nanospheres (25–90 nm), termed carbon “nanobubbles”. They bear superior dispersability in water and distinctive graphitic order. Herein, we describe the nanobubble‐assisted dispersion of CNTs in aqueous solution upon sonication. This process relies on the π–π interaction between the two aromatic carbon nanostructures, which can process their carbon mixture in water into conductive filter membranes, ink, and discs. This stabilization can be extended to other aromatic carbons. In addition, the π–π interaction may create a new type of carbon p–n junction that can be used to improve charge separation.     

Growth of Single-walled Carbon Nanotubes on Substrates Using Carbon Monoxide as Carbon Source

The growth of single-walled carbon nanotubes(SWCNTs) on substrates has attracted great interests because of the potential applications in various fields. Carbon monoxide(CO) was used as the carbon source for the growth of SWCNTs on silicon substrates. Random or oriented SWCNTs can be produced by varying the CO flow rate. When the flow rate of CO was as low as 20 sccm(sccm:standard cubic centimeter per minute), dense SWCNT networks with clean surface were produced. When the flow rate was above 50 sccm, vertically aligned SWCNT(VA-SWCNT) arrays were grown. Well-aligned VA-SWCNT arrays were obtained in the temperature range of 650-800℃ and the content of large-diameter(above 1.7 nm) tubes in the array increased with the temperature. The height of the array was affected by the growth temperature, the CO flow rate, and the growth time. These findings indicate CO can be used as an efficient carbon source for the growth of SWCNTs on substrates under low flow rates.     

二氧化碳与低碳经济发展

由于二氧化碳无色无味,又存在于大气中,因此它在植物生长中的重要性被人类忽略了。其实二氧化碳是光合作用的反应物,是植物生长的重要原料;又是一种新型绿色肥料。人类应该着力开发以二氧化碳为原料的新型肥料发展低碳经济。     

碳纳米管含量对炭炭复合材料组织及力学性能的影响

炭纤维上原位合成了均匀生长且具有伸张形貌的碳纳米管,借助化学气相渗透制备了碳纳米管增强的炭炭复合材料,研究了不同含量的碳纳米管对炭炭复合材料组织和力学性能的影响。结果表明：炭纤维上生长碳纳米管改变了热解炭的沉积行为,诱导了各向同性热解炭的生成,且随着碳纳米管含量的增加,各向同性热解炭的厚度增加,但是复合材料的d002值却明显降低。微量的碳纳米管即可显著提高复合材料的力学强度,随着其含量的增加,复合材料的力学强度和模量迅速提高,但材料的断裂行为却急剧恶化,断裂模式由最初的假塑性断裂转变为脆性断裂。     

Palladium-Catalyzed Addition of Carbon Monoxide and Carbon Tetrachloride to 1-Octene in Supercritical Carbon Dioxide

The Pd-catalyzed addition of carbon monoxide and carbon tetrachloride to 1-octene gave coadduct [alkyl 2-( 2, 2, 2-trichloroethyl)octanoate] as the major product in supercritical carbon dioxide by using pyridine as the base. It was found that the selectivity and the yield of coadduct were greatly affected by the pressure of carbon dioxide, the reaction temperature and the amounts of alcohol and base used.     

一维新型碳的同素异形体:碳链

碳链是一种完全一维的、具有电子轨道sp杂化结构的新型碳的同素异形体.正是由于碳链的独特的一维结构,使其拥有区别于富勒烯、石墨烯和碳纳米管的化学键,从而表现出更加优异的性能,如:理论预言碳链的机械强度是石墨烯的几倍;碳链的导热也类似于石墨烯和碳纳米管;碳链是具有直接带隙的半导体材料,且带隙的大小可以通过其长度来调控,其长...     

具有螺共轭结构的碳的同素异形体:glitter碳

介绍碳的新的同素异形体glitter碳的结构及螺共轭特征,对碳的同素异形体的结构进行了比较。     

Adsorption of Carbon Monoxide on Oxidized Activated Lignin Carbon

Experimental data on the dynamics of carbon monoxide adsorption on oxidized activated lignin carbon are presented.     

埃洛石纳米管模板法一步法制备一维碳纳米管/碳纳米棒混合纳米碳材料

利用埃洛石纳米管(HNTs)特有的中空纳米结构,以及丰富的界面化学性质,以聚乙烯醇(PVA)为碳源,采用浸渍填充纳米孔方法实现了一步制备一维碳纳米管(CNTs)/碳纳米棒(CNRs)混合纳米碳材料。考察模板剂(HNTs)和碳源(PVA)之间的比例关系对混合纳米碳材料的结构影响,利用XRD、FTIR、Raman、N2吸附-脱附测试、TEM、SEM以及电阻率和分散性等表征手段分析混合纳米碳材料的结构变化。结果发现,PVA填充含量的增加将导致产物中CNRs的质量分数增加;当PVA和HNTs质量之比为1∶1时,所制备的CNTs/CNRs的孔体积达到最大值2.142 cm~3·g-1,比表面积达到583 m~2·g-1,并且表现出较好的电导率和分散性,表明低的PVA填充比例制备的混合碳材料中CNTs含量较高。