大碳层间距的沥青基多级孔碳材料的制备及其在超级电容器中的应用

基于KOH活化法,以纳米级片层多孔MgO为模板剂,制备大碳层间距的沥青基超级电容器用多级孔碳材料。考察了模板剂添加量对多孔碳材料孔分布、碳层间距等理化性能及电化学性能的影响。结果表明模板剂添加量为沥青质量的25%时,多孔碳材料比表面积、孔体积分别为2 634 m~2·g~(-1)、1.12 cm~3·g~(-1),碳层间距高达0.374 nm,用于超级电容器电极材料时,1和20A·g~(-1)电流密度下的比电容分别为338和277 F·g~(-1),经过10 000次循环恒电流充放电,1 A·g~(-1)下容量保持率为93.5%,展现了优异的电化学性能。     

活性炭/有机质复合相变材料的热-电性能

用活性炭(AC)作为支撑材料,石蜡(PW)、十六酸(PA)和硬脂酸(SA)作为相变主材,通过熔融共混法制备AC/PW、AC/PA和AC/SA复合相变材料,并考察了其热-电性能。结果表明,添加活性炭时有机质均不会泄漏;复合材料充-放热过程中温度场分布都比较均匀,热循环会使材料导热性能略有下降;此外,三种复合材料的电阻率均随压力增加而减小。     

不同铈添加量对CeO2-ZrO2-Al2O3材料性能的影响

采用共沉淀法制备了一系列不同铈添加量的CeO2-ZrO2-Al2O3(CZA)储氧材料,并通过XRD、低温N2吸附-脱附、氧脉冲吸附(OSC)和H2-TPR等手段进行了表征。XRD结果表明,在1 000和1 100℃高温焙烧后,当CeO2添加量为8%时样品具有最好的结构稳定性能。N2吸附-脱附结果表明,CeO2添加量为8%时样品具有最好的织构性能,1 000℃时,比表面积和孔容分别为:136.6 m2.g-1和0.38 mL.g-1;1 100℃时,比表面积和孔容分别为:83.7 m2.g-1和0.23 mL.g-1。OSC结果显示,CeO2添加量为8%时样品具有最大的储氧量,1 000℃和1 100℃分别为70μmol.g-1和31μmol.g-1。H2-TPR结果表明,CeO2添加量为8%时样品具有最佳的还原性能。     

氯离子对铜在玻碳电极上电结晶的影响

采用线性扫描伏安法和计时安培法研究了硫酸铜溶液中铜在玻碳电极上电结晶 的初期行为。在含与不含氯离子的0.05mol·L~(-1) cUso_4-0.5 mol·L~(-1) H_2SO_4电解液中,循环伏安实验结果表明铜在玻碳基体上的沉积没有经过UPD过 程;氯离子明显使Cu的沉积和氧化峰变得尖锐,促进Cu的沉积速度。计时安培实验 结果表明,Cu的电结晶按瞬时成核和三维生长方式进行。氯离子不改变Cu的结晶机 理,但在I～t曲线中,导致电流达最大(I_m)所需的时间t_m减小、晶核数密度和生 长速度增大,从而明显改变Cu沉积层的质量。当Cl~-浓度在10～20mg·L~(-1)范围 内,成核的晶核数密度达较大,即氯离子的最适宜添加量。     

柠檬酸中锌防蚀剂(1,3-Dioxolan-2-ylmethyl)三苯基溴化磷和碘离子的协同效应研究（英文）

采用称重法、动电位极化法和电化学交流阻抗技术研究了30oC时(1,3-Dioxolan-2-ylmethyl)三苯基溴化磷(DTPB)对0.5 mol·L-1柠檬酸中锌腐蚀行为的影响.通过在环保型电解槽中对锌进行酸洗,这在文献中是不常用的.结果表明,DTPB作为一种有效的防蚀剂,添加浓度仅为3×10-3mol·L-1时,锌在柠檬酸溶液中的防蚀效率可达98.9%.由于DTPB和碘化钾存在协同效应,两者联用时的防蚀效果要比单独使用DTPB强,防蚀参数为1.2,并随温度升高而减小.本文提出了碘化钾作为吸附媒介,可使金属表面与DTPB结合的防蚀机制.     

锂离子电池新型正极材料xLiF-(Ni_(1/6)Co_(1/6)Mn_(4/6))_3O_4的制备及电化学性能研究

采用高能球磨法通过不同球磨时间制备xLiF-(Ni_(1/6)Co_(1/6)Mn_(4/6))_3O_4新型正极材料,并对材料进行石墨烯复合改性,提高其性能。结合X-射线衍射、扫描电镜、电化学性能测试和X-射线电子能谱对所制备的正极材料性能进行表征。结果表明,球磨24h的产物的放电比容量最高,为157. 3mAh·g~(-1)。此外,正极材料添加石墨烯能改善其电化学性能,当石墨烯复合量为20%,在室温、0. 05C(1C=250mAh·g~(-1))、1. 5～4. 8V下,材料首圈的放电比容量为235mAh·g~(-1),相较于无石墨烯的材料,在1C和5C倍率下,放电比容量分别提高到151和114 m Ah·g~(-1)。文中还分析了正极材料放电容量随截止电压的变化,确定了复合正极材料在高电压下有获得更高放电容量的潜力。     

正交法优化前处理-气相色谱测定菠萝罐头中的二溴乙烷残留量

建立了蒸馏-气相色谱测定菠萝罐头中二溴乙烷残留量的方法。采用正交法优化正己烷-丙酮混合提取液的配比及盐添加量。回收率结果表明,影响提取效果的因素依次为蒸馏溶剂体积比无水硫酸钠添加量蒸馏水添加量。最佳蒸馏提取条件为:无水硫酸钠添加量20g,蒸馏水添加量150mL,蒸馏溶剂为正己烷-丙酮(2∶1)。方法检出限为0.5μg/kg;在0.5、1.0、5.0、10μg/kg4个加标水平下的平均回收率为99%～106%;相对标准偏差为3.1%～7.0%。该方法简便、快速、灵敏、准确,适用于菠萝等水果罐头中二溴乙烷残留量的测定。     

聚(3-己基噻吩)包覆富锂层状正极材料Li1.18Ni0.15Co0.15Mn0.52O2的制备与电化学性能

采用溶胶-凝胶法合成了Li_1.18Ni_0.15Co_0.15Mn_0.52O₂富锂层状正极材料, 并使用聚(3-己基噻吩)对其进行了表面包覆. 采用多种光谱学和电化学手段对材料的形貌结构和电化学性能进行了分析. 结果表明, 聚(3-己基噻吩)溶液浸泡后在富锂材料表面形成厚约1.5 nm的均匀包覆层. 表面包覆后富锂层状正极材料的极化和阻抗明显减小. 在0.2C倍率下, 经过100次充放电循环后, 未包覆的富锂材料放电比容量衰减为170 mA·h/g, 而经过0.3%聚(3-己基噻吩)包覆的材料的放电比容量则保持在205 mA·h/g, 容量保持率由68%提高到82%; 10C倍率下的放电比容量由72 mA·h/g提高到116 mA·h/g.     

添加Y_2O_3对TiN-Sialon-Al_2O_3复相材料的制备与冲蚀磨损性能的影响

采用铝热还原氮化法原位制备了TiN-Sialon-Al_2O_3复相材料,探讨了Y_2O_3添加量对TiN-Sialon-Al_2O_3复相材料的物相组成、微观结构和固体粒子冲蚀磨损性能的影响。结果表明:添加Y_2O_3能够显著提高TiN-Sialon-Al_2O_3复相材料的抗折强度。Y_2O_3在高温下形成Y-Si-Al-TiO-N低共融相,起到弥合气孔及愈合裂纹的作用,促进了复相材料的烧结致密。Y_2O_3添加量5%时,材料在室温和1400℃下的冲蚀磨损性能最好,体积冲蚀磨损率最小分别为1.99和0.65 mm~3·g~(-1)。添加Y_2O_3后形成的Y-Si-Al-Ti-O-N玻璃相1400℃下发生软化并产生塑性,减弱了材料受到的磨削和切削作用,提高了TiN-Sialon-Al_2O_3复相材料的冲蚀磨损性能。     

MoO2/C共包覆Si/石墨复合锂离子电池负极材料的研究

采用溶胶-凝胶法, 用二氧化钼(MoO₂)和C共同包覆Si/石墨粒子制备了Si/石墨/MoO₂/C锂离子电池负极材料. 利用X射线衍射(XRD)、 扫描电子显微镜(SEM)、 透射电子显微镜(TEM)、 循环伏安(CV)和电化学阻抗(EIS)等分析了材料的形貌和性质. 结果表明, MoO₂/C的共包覆在缓解材料体积膨胀的同时提高了材料的电子和离子电导率, 进而提高了材料的电化学性能. 复合材料的首次充电比容量为2494 mA·h/g, 首次库仑效率为72%, 经过100次循环后比容量为636.6 mA·h/g.     

Influence of high-volume electric furnace nickel slag and phosphorous slag on the properties of massive concrete

This study applied high-volume electric furnace nickel slag (FS), phosphorous slag (PS) and a mixture of the two (FP) to massive concrete, and using fly ash (FA) as the control admixture, investigated the effects of FS and PS on the hydration and hardening process of the cementitious materials, the mechanical properties and the durability of the concrete. Two curing conditions were set, namely the standard curing condition and temperature-matched curing condition (or constant 25 and 50 °C). The hydration heat, hydration products, pore size distribution, mechanical properties and ability of the concrete to resist chloride ion penetration were tested. The results show that the activity of PS and FP is higher than that of FA, while that of FS is lower than that of FA; the improvement of FP on the pore structure of the hardened paste is close to that of FA at late ages under the standard curing condition but better than that of FA at all ages under the temperature-matched curing condition; high-volume FP concrete shows similar or even superior mechanical properties and permeability to chloride ions of concrete to high-volume FA concrete at late ages under both curing conditions.     

Comparison between the effects of superfine steel slag and superfine phosphorus slag on the long-term performances and durability of concrete

Superfine particles have been used as mineral admixtures to enhance physical properties, mechanical properties, and durability of concrete in a lot of research. In this study, superfine steel slag (FSS) and superfine phosphorus slag (FPS) were ground to 643 and 657 m² kg^?1, respectively. The water-to-binder (W/B) ratios were set as 0.45 as well as 0.35, and the cement replacements adopted were 15 and 30%. The effects of FSS and FPS on long-term performance and durability of concrete were investigated. The results show that the increase amplitude of reaction degree of FPS is higher than that of FSS at late age (after 90 days). FPS can improve the pore structure of concrete which is beneficial to the resistance to carbonation and chloride ion penetration for concrete at late age while FSS cannot. FPS is also more advantageous to the development of compressive strength and splitting tensile strength of concrete when compared to FSS at late age. FPS is much more beneficial to the resistance to sulfate attack of concrete while FSS is more disadvantageous to the resistance to sulfate attack of concrete as the replacement ratio increases.     

Determination of cross-linking residues in a pharmaceutical polymer by liquid chromatography-high resolution full scan mass spectrometry

A liquid chromatography-mass spectrometry (LC-MS) method was developed as limit test for an amine cross-linking residue in a pharmaceutical polymer. The method was based on full scan data with extracted ions for the accurate masses of dicyclohexylmethane-4, 4'-diamine (DMDA) and the internal standard 1,12-diaminododecane (DADD) obtained by Fourier transform MS. Dicyclohexylmethane-4,4-diisocyanate (DMDI) the reactive form of the cross-linking residue was determined as it decomposition product DMDA. Calibration curves for quantification of DMDA were linear in the range 2-100 ng/ml, the LOD was 1 ng/ml or 10 pg on column. Precisions/recoveries for spiked samples at the level of the limit of 1 ppm for DMDA and DMDI were +/-9.6%/38.6% and +/-14.5/10.0% (n=3), respectively. Unpredictable recovery was found in the extraction of polymer samples because of the complexity of the matrix and the reactivity of dicyclohexylmethane-4,4-diisocyanate (DMDI). PEG residues extracted from the polymer were found to cause ionization suppression and also affected the chromatography, these effects were reduced by using a gradient program. By using this method the level of amine residues in samples from different batches of polymers were determined to be much lower than the limit of 1 ppm. The method allowed comparison of the results obtained from the polymer before and after purification indicating that the residual DMDA could be decreased by a washing procedure.     

多点位吸附型咪唑啉季铵盐缓蚀剂的合成及其缓蚀性能

以对二甲氨基苯甲酸、二乙烯三胺和氯化苄为原料,两步法合成了一种新型具有多个潜在吸附中心的季铵盐型咪唑啉缓蚀剂（MIQ）,利用傅里叶变换红外光谱对合成的产物进行了表征。 通过失重法研究了该缓蚀剂在6%盐酸溶液中对碳钢的缓蚀性能。 讨论了缓蚀剂用量、温度、时间对缓蚀性能的影响,并研究了其与某些物质复配后的协同作用。 结果表明,合成的季铵盐型咪唑啉缓蚀剂在6%的盐酸腐蚀环境中,用量为0.5%时对碳钢的缓蚀率可达97%以上,缓蚀率随温度的升高和时间的延长而降低。 MIQ与乌洛托品、KSCN以及KI等复配后可以显著改善缓蚀剂的缓蚀率。 从吸附等温线推测,该缓蚀剂抑制腐蚀的机理是缓蚀剂在碳钢表面吸附成膜,进而有效阻挡了碳钢表面与酸性清洗试剂的接触。     

Combined modification of asphalt with polyethylene packaging waste and organophilic montmorillonite

Organophilic montmorillonite (OMMT) was prepared via ion exchange of Ca-montmorillonite (Ca-MMT) using dioctadecyl dimethyl ammonium chloride (DDAC). The OMMT and polyethylene packaging waste (WPE) were used as a combined modifier for asphalt, and the microstructure and performance of the modified asphalt were studied. Results show that the organophilic modification with DDAC results in an obvious increase of interlayer spacing of Ca-MMT, and the OMMT nano-lamellas can be completely exfoliated during the preparation of modified asphalt. The WPE, dispersed in asphalt, exhibits relatively small particles with homogeneous distribution, indicating that the OMMT addition is beneficial for the dispersion of WPE in asphalt. Compared with ordinary polymer modified asphalt, the penetration, softening point and ductility of the modified asphalt are all markedly improved. The modified asphalt obtained possesses excellent high-temperature stability, low-temperature anti-cracking performance and deformation resistance.     

Controlled potential coulometric technique for the determination of thorium

A method based on controlled potential coulometry has been developed for the determination of thorium, using mercury as a working electrode. A known amount of EDTA is titrated coulometrically in the absence and in the presence of thorium. The difference in Coulombs obtained in these two titrations corresponds to the amount of thorium present in the aliquot. 0.5M sodium acetate has been used as a supporting electrolyte. Precision for thorium determination in the range of 4–8 mg is found to be better than ±0.2%.     

焙烧水滑石对含氯中性化混凝土孔隙液中钢筋腐蚀行为的影响

研究了碳酸根型镁铝水滑石(LDH-MgAl-CO3)焙烧产物(CLDH)在含氯离子的中性化混凝土模拟孔隙液中对钢筋腐蚀行为的影响.极化曲线电位监测以及EIS测试表明,经CLDH处理后的孔隙液中钢筋的极化曲线出现明显的钝化区间,其腐蚀电位较未处理的有一定提高,表面的阻抗也有较大增加.此外,离子浓度分析发现,较未处理时,经CLDH处理后的孔隙液其[Cl-]/[OH-]值降低了4～5个数量级.     

Evaluation of Anticorrosion of NaNO2 on Reinforcing Steel in the Simulated Concrete Solution

Reinforcing steel in concrete is usually in a passive condition due to the high alkalinity of the pore solution contained in the pores of concrete. However, the passivation may be lost and the corrosion occurs on the steel by a deceased of pH due to carbonation and/or by the penetration of chloride ions which come from the corrosion environment at the metal concrete interface. Pitting corrosion caused by the chloride is most harmful. Corrosion inhibitors can be applied to protect steel in the presence of chloride ions. The anticorrosion action of NaNO₂ on the reinforcing steel in the simulated concrete solution containing NaCl has been studied using electrochemical technique and the other methods in this paper.     

The effect of chloride concentration and pH on pitting corrosion of AA7075 aluminum alloy coated with phenyltrimethoxysilane

The effect of chloride ion concentration and pH of solution on the corrosion behavior of aluminum alloy AA7075 coated with phenyltrimethoxysilane (PTMS) immersed in aqueous solutions of NaCl is reported. Potentiodynamic polarization, linear polarization, open circuit potential, and weight loss measurements were performed. The surface of samples was examined using SEM and optical microscopy. Elemental characterization of the coating by secondary ion mass spectrometry indicates an intermediate layer between coating and aluminum alloy surface. The corrosion behavior of the aluminum alloy AA7075 depends on chloride concentration and pH of solution. In acidic or neutral solutions, general and pitting corrosion occur simultaneously. On the contrary, exposure to alkaline solutions results in general corrosion only. Results further reveal that aluminum alloy AA7075 is susceptible to pitting corrosion in all chloride solutions with concentrations between 0.05 M and 2 M NaCl; an increase in the chloride concentration slightly shifted both the pitting and corrosion potentials to more active values. Linear polarization resistance measurements show a substantially improved corrosion resistance value in case of samples coated with PTMS as compared to uncoated samples in both neutral (pH = 7), acidic (pH = 0.85 and 3), and alkaline chloride solutions (pH = 10 and 12.85). The higher corrosion resistance of the aluminum alloy coated with PTMS can be attributed to the hydrophobic coating which acts as a barrier and prevents chloride ion penetration and subsequent reaction with the aluminum alloy.     

紫外光-热双固化聚苯胺防腐涂料

以酸性磷酸酯为掺杂剂对本征态聚苯胺(EB)进行掺杂,制备了可在聚氨酯和聚氨酯丙烯酸酯中进行纳米分散的导电聚苯胺(ES),其粒径分布在80~750 nm之间可控。 在此基础上,制备了不含重金属的紫外光-热双固化聚苯胺防腐涂料。 该防腐涂料先后经过3~5 s紫外光固化和80 ℃下1~3 min的热固化,即可完成紫外光-热双固化过程。 由于ES与聚氨酯或聚氨酯丙烯酸酯之间是不相容体系,因此随着ES质量分数的增大,会导致ES的团聚,分散粒径增大。 当ES质量分数从1.0%增大到5.0%时,ES的粒径从80~119 nm增加到500~750 nm。 ES的分散粒径增大会导致防腐涂层的致密性变差,降低防腐效果。 与普通紫外光固化聚苯胺防腐涂层相比,当ES为1.0%时,紫外光-热双固化防腐涂层在质量分数为3.5%的NaCl水溶液中浸泡2160 h后,其0.1 Hz下的绝对阻抗值(|Z|_{0.1 Hz})仍高于1.0×10⁸ Ω·cm²,优于普通紫外光固化聚苯胺防腐涂层的|Z|_{0.1 Hz}(1.0×10⁷ Ω·cm²),表明紫外光-热双固化涂层的防腐效果有了显著改善。 经过500 h划叉中性盐雾试验后,普通紫外光固化防腐涂层的板面出现了锈蚀宽度小于1 mm的锈蚀,而紫外光-热双固化防腐涂层经过500 h划叉中性盐雾试验,板面没有出现生锈、起泡的现象,表明紫外光-热双固化路线对提高涂层的防腐性能具有较大的价值。