碳纤维电极的研制

本文详细叙述了碳纤维电极的研制工艺，并对其性能进行了测试，碳纤维电极的峰高均值为268．57μ A/V，变异系数为1．213％。GC电极的峰高均值为37.3μ A/V，变异系数为1．553％，碳纤维电极具有比GC电极更高的稳定性。在5．0mg/L Hg^2 -0.12mole/L盐酸溶液中测量铅，检测限达到0．020μ g/L(电富集600秒)，并且用于血液中痕量铅的测定，标准加入回收率为93．5％。RSD(n＝11)＜8．3％。     

齿瓣延胡索细胞悬浮系的建立和延胡索乙素的形成

就各种因素对齿瓣延胡索悬浮细胞生长和延胡索乙素形成的影响做进一步的研究。结果表明：随着接种量的提高，细胞生长加速，培养液浊度增大，齿瓣延胡索细胞悬浮液培养中最适接种量为2g/30ml;pH5.6最有利于细胞生物量的积累；2，4—D与2种细胞分裂素的组合，对于生长量积累和THP含量的作用最显著；在培养基中添加甘露糖和半乳糖，对于提高培养物THP含量是有效的；G1y Phe Lys的作用效果最显著，细胞鲜质量、干质量和THP含量均最高。     

糖精钠和山梨酸电极产物的高效液相色谱分析

用电化学和高效液相色谱法对糖精钠和山梨酸在-1．6V处的还原进行分离和表征，为鉴定电极反应，推断电极反应机理，提供了一种新的方法．     

等离子体离子注入类金刚石多层膜机械特性

采用非平衡磁控溅射及等离子体离子混合注入方法在奥氏体不锈钢 1 Cr1 8Ni9Ti基体上制备 N/ Ti N/ Ti(N,C) / DLC梯度膜 .研究了类金刚石 (DLC)梯度膜的结构特征和力学性能 .试验结果表明 ,N/ Ti N/ Ti(N,C) / DLC梯度膜最外层为典型的 DLC层 .梯度膜的硬度、弹性模量、断裂韧性以及界面结合强度值分别为 1 9.84GPa、1 90 .0 3GPa、3.75MPa· m1/ 2和 5.68MPa·m1/ 2 .试验所制备的 DLC多层膜比 DLC单层膜具有更好的综合机械性能 .     

富勒醇聚醚聚氨酯的热性能

通过水溶性多羟基化合物C60(OH)n和聚醚聚氨酯(PEO—PU)预聚体反应合成了一系列新型的C60星形聚醚聚氨酯，并用傅里叶红外分析(FTIR)、差式扫描量热分析(DSC)、热重分析(TGA)等手段对其性能进行了表征．结果表明，C60星形聚醚聚氨酯比线性的聚醚聚免酯具有更高的柔顺性和热稳定性；随着聚氧化乙烯数均分子量Mn的增加，C60星形聚醚聚氨酯的玻璃化转变温度(Tg)降低，热分解温度(td)提高．     

碳纤维表面特性对反硝化菌固着化的影响

通过对比反硝化菌在不同基体碳纤维表面的固着化及碳纤维表面含氧官能团对菌种的固着化实验,研究了碳纤维(基体、比表面积、循环利用性等)特性,尤其表面含氧官能团对反硝化菌固着化的影响。实验结果表明,反硝化菌在PAN基碳纤维上的平均挂膜厚度明显高于沥青基和粘胶基碳纤维。碳纤维表面适量的含氧官能团有助于较多、较牢固地固着反硝化菌。对三种PAN基碳纤维的XPS谱图分析表明碳纤维表面含氧官能团—O—CO对反硝化菌的固着化影响较大,当碳纤维表面含氧官能团—O—CO中碳原子占表面碳原子总量的3%左右时反硝化菌固着化效果较佳。经过比较表明PAN基碳纤维是一种生物相容性好、固着化程度高、再生能力强、耐微生物分解及化学腐蚀的优异的新型反硝化菌固着化载体。     

多孔陶粒结晶床除磷试验研究

实验以多孔陶粒为载体，在一定条件下，利用非均相及二次成核作用在陶粒表面沉积一层羟基磷酸钙晶体，从而培养出初级晶种．实验将粒径为1．25mm多孔陶粒与石英砂相对比，结果表明采用多孔陶粒作载体形成结晶体效果较好．用该晶种的连续流固定床除磷，获得令人满意的效果．当原水含磷质量浓度在2～5mg/L范围内时，空床线速不大于2．5m/h，水力停留时间不小千12min时, 脱磷固定床除磷率较高且稳定，磷去除率可达90％以上．     

Isotopic evolution of the terminal Neoproterozoic and early Cambrian carbon cycle on the northern Yangtze Platform, South China

Profound geotectonic, climatic and biological changes occur during the terminal Neoproterozoic and its transition into the early Cambrian. These are reflected in temporal variations of the chemical and isotopic composition of seawater. We are studying a sequence of sedimentary rocks at the Shatan section, northern Yangtze Platform, Sichuan Province of China. This succession comprises, in ascending stratigraphic order, predominantly calcareous sediments of the Sinian upper Dengying Formation and black shales of the lower Cambrian Guojiaba Formation (time equivalent of Niutitang Fm.). Paleoenvironmental setting represents shallow-water shelf deposits. The objective of our study is to provide temporal records for the isotopic compositions of organic and carbonate carbon throughout this time interval. Organic carbon isotope values display a range between -35.8‰ and -30.1‰ with clear stratigraphic variations. Carbonate carbon isotope data vary between -3.5‰ and +0.5‰. These secular variations are interpreted to reflect perturbations of the global carbon cycle, specifically changes in the fractional burial of organic carbon. However, local conditions have further affected the isotopic signals.     

碳钢粉末渗铝试验研究

对 2 0碳钢进行了粉末包埋渗铝试验 ,优化了渗剂配方及渗铝工艺。采用X射线衍射仪分析了渗铝层的相成分 ,并对渗铝层的微观组织和渗铝钢的力学性能进行了测试。结果表明 ,使用 3号渗剂的 2 0碳钢的表面渗铝效果最好。 2 0碳钢渗铝层内未出现高铝脆性相 (FeAl3 、Fe2 Al5等 ) ,这有利于改善渗铝钢的力学性能和焊接性能。 2 0碳钢经渗铝处理后 ,其机械性能略有降低 ,高温持久性能明显降低 ,而抗高温氧化性能大大提高。     

Climatic significance of stable carbon isotope in tree rings of Abies spectabibis in southeastern Tibet

The annually cross-dated stable carbon isotope of tree-ring a-cellulose of Abies spectabibis collected from the southeastern Tibetan Plateau is used to examine its rela-tionship with climatic parameters. The residual D13C series in treerings is constructed after removing the effects of age trend and rising CO2. We found a close relationship between D13C in tree rings and the relative humidity of September—November of the previous year measured at the nearby Ny-ingchi Meteorological Station, albeit a strong 搇agged effect? Thus we developed a transfer function to reconstruct the autumn relative humidity for the Nyingchi region, which explained 37.9% of the total variance (p < 0.001). Our results suggest a high frequency and moderate amplitude variance of the relative humidity before 1800, and the variance re-versed afterwards.