用拉曼光谱研究T800级碳纤维的均质化程度

提出了一种用于拉曼光谱测试的碳纤维截面和剖面样品的制备方法,采用拉曼光谱分别对国产JHT55、P278F和日本东丽T800S碳纤维的截面和剖面做成像扫描,通过比较碳纤维在各个维度上的石墨化程度,系统分析了其径向、轴向以及赤道方向的均一化程度。结果表明,3种T800级碳纤维均存在皮芯结构,轴向、赤道方向也有一定程度的不均匀性,东丽T800S整体的均一化程度远优于两种国产碳纤维。高度均质化是东丽T800S性能优于国产T800级碳纤维的重要原因。     

高强高模型碳纤维与高模型碳纤维微观结构分析

利用拉曼光谱(Raman)、X射线衍射(XRD)、X射线光电子能谱(XPS)、元素分析(EA)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和小角X射线散射(SAXS)表征和分析了高强高模型碳纤维和高模型碳纤维的微观结构和化学组成.结果表明,高强高模型碳纤维的石墨微晶晶粒尺寸细小,组成微晶的石墨片层间距较大,片层间和片层边缘保留了非共轭碳构成的晶体缺陷,石墨化程度较低,微晶间缝隙较小,分布均匀,路径曲折;高模型碳纤维具有更加完善的石墨微晶结构,石墨化程度较高,微晶尺寸更大,组成微晶的石墨层堆砌整齐有序,非碳元素较少,共轭态碳明显增多,但其微晶间裂纹和孔隙结构也较大.高强高模型碳纤维因具有多层次的微观结构和缺陷,相比高模型碳纤维,有更多的应力扩散和能量存储及耗散路径,是其拉伸应变和强度保持的关键所在.     

低阶煤热萃取物与瘦煤共炭化焦炭的微观结构及显微强度研究

以众唯瘦煤作为主炼焦煤,大同长焰煤萃取物作为添加剂,进行共炭化处理制备坩埚焦。利用偏光显微镜法定量研究焦炭光学显微组分,获得焦炭的各向异性指数(DRAS);采用XRD及分峰拟合的方法研究了焦炭的微晶粒径(L_c)、芳香缩合度(I_a)、石墨化度(g);利用Raman光谱结合分峰拟合的方法研究了焦炭中理想石墨微晶含量(I_g)。对所得焦炭的光学显微组分进行定量分析发现:大同长焰煤热解萃取产物的添加对共炭化焦炭的光学显微组分有显著的影响,利用偏光显微镜法计算出焦炭的DRAS与XRD和Raman计算的焦炭微晶参数呈现很好一致性。并且,焦炭的显微强度与其微观结构关联性极大。     

石墨负极电化学扫描循环过程的EIS、Raman光谱和XRD研究

运用电化学阻抗谱(EIS)、Raman光谱和XRD研究了石墨负极在1 mol/L LiPF6-EC∶DEC∶DMC电解液中的电化学循环扫描过程. EIS研究结果表明, 在电化学循环扫描4~10周范围内, SEI膜(固体电解质相界面膜)电阻随循环扫描周数增加近似线性增长, 但石墨负极/电解液界面总阻抗由于电荷传递电阻的降低而减小. Raman光谱研究结果表明, 在经历电化学循环扫描后, 活性材料表层发生粉化和无定形化, 石墨化程度降低; 但XRD研究结果显示, 石墨材料的本体结构没有发生变化, 仍然保持着完整的石墨层状结构.     

含Fe、Co、Ni的层状双金属氢氧化物为催化剂前体生长碳纳米管

分别以具有相似Fe、Co、Ni含量的层状双金属氢氧化物(LDHs)为催化剂前体,用化学气相沉积的方法生长碳纳米管(CNTs).催化剂由LDHs焙烧还原得到.通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)及拉曼光谱(Raman)测试技术对LDHs及其焙烧产物的结构、CNTs的形貌和结构进行了研究.结果表明,3种催化剂生长的CNTs均为多壁结构;其中Co催化剂活性较低,生长CNTs的管径较细、石墨化程度较高;Ni催化剂的活性较高,生长CNTs的密度较大、管壁较厚、石墨化程度较差;Fe催化剂的活性介于Co和Ni之间.催化剂活性及CNTs的密度可以由生长CNTs的结构来解释.     

无机酸洗脱对胜利褐煤微晶结构及其自燃倾向性的影响

利用XRD、Raman、XPS和FT-IR表征技术,研究无机酸洗脱(HCl、H2SO4、HCl-HF)处理的胜利褐煤微晶结构的变化,采用自行设计的表面吸附仪-GC联用装置,对样品进行不同温度的低温脉冲氧化实验,考察了煤样在不同温度下氧吸附量的变化规律,通过低温脉冲氧吸附规律与TG/DTG和固定床燃烧实验关联,考察了煤样的自燃倾向。结果表明,无机酸洗脱对矿物质的脱除使得煤结构的有序度增加,石墨化程度提高,无机酸洗脱煤样与原煤相比吸氧量明显下降。随着吸附温度的升高,各煤样吸氧量明显增加,且随着脱除矿物质程度的增加,吸氧量呈减小的趋势,导致自燃倾向降低。     

磷化钼基催化剂的制备及其电解水中的应用

以十二胺插层的正交三氧化钼为前驱体,次磷酸钠分解产生的PH3作为磷源,在限域的空间内通过原位碳化磷化法,合成了"N掺杂MoP/石墨"复合材料.通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、X射线光电子能谱分析(XPS)、拉曼光谱分析(Raman)和比表面积测试法(BET)等手段对700、...     

XRD和Raman法评估热解气氛中H_2和CO对半焦化学结构的影响

采用XRD和Raman光谱分析方法研究了神木煤在热解主要温度区间(450-750℃)及在三种热解气氛(N_2、含H_2及含CO)下的化学结构演变规律,并比较了两种方法所获结构参数的相关性。结果表明,原煤在N_2气氛下热解制备的半焦,其炭微晶尺寸在横向上不断增长,纵向上层面间距逐渐增大,堆垛高度在650℃左右剧烈转变; Raman参数A_(D_1)/A_G增加,而A_G/A_(all)降低,表明半焦有序性结构比例降低。热解气氛中的H_2促进了炭微晶结构的纵向发展,提高了小分子基团的转化程度,使得半焦有序化程度升高。热解气氛中的CO对炭微晶结构参数影响小于H_2气氛,但在700℃以下,CO因析炭作用产生的致密炭颗粒包裹于半焦表面,导致半焦炭有序化程度提高。半焦的L_c与A_G/A_(all)及d_(002)与A_(D_1)/A_G之间存在一定相关性; L_a与A_(D_1)/A_G呈较好的正相关性。     

气凝胶催化剂上甲烷裂解制备的碳纳米管结构特征

采用XRD、TGA、SEM、TEM、 Raman光谱等多种表征手段,考察了Al2O3气凝胶催化剂上甲烷裂解生长的碳纳米管的结构特征.制得的碳纳米管形态单一,为管径均匀、管壁光滑的中空纳米管,平均直径在10～20 nm.碳纳米管的比表面积较大,具有较强的抗氧化能力,其结构的长程有序度较石墨低.由碳纳米管的Raman光谱分析可知,碳纳米管存在碳层缺陷和无定形碳.当反应温度升高或甲烷浓度下降时,碳纳米管石墨化程度逐渐提高.     

微晶碳电活化过程中离子尺寸效应研究

以石油焦基微晶碳作为电极材料,并由N2吸附,X射线衍射(XRD)表征其孔结构和微晶结构.研究了4种电解液Et4NBF4/PC(四乙基铵四氟硼酸盐/碳酸丙烯酯)、Et4NBF4/AN(四乙基铵四氟硼酸盐/乙腈)、Bu4NBF4/PC(四丁基铵四氟硼酸盐/碳酸丙烯酯)和Bu4NBF4/AN(四丁基铵四氟硼酸盐/乙腈)的微晶碳电容器特性.结果表明:电解质离子与溶剂AN的溶剂化半径较小,容易嵌入类石墨微晶碳层,其于AN的电活化电位比在PC中的低,致使电活化程度更深,材料的表面利用率更高,电容量较大.电解质阳离子(Et4N+,Bu4N+)大小对电活化影响不大.电活化使材料类石墨微晶层间距(d002)变大,离子尺寸越大,层间距增加越明显.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。