采用傅里叶变换红外测试氧化淀粉中的羧基含量,以国标法测得的羧基含量为纵坐标,谱图中羰基吸光度与C—H键吸光度比值为横坐标绘制得到标准曲线。对未知氧化淀粉产物进行红外测试,得到吸光度比值通过标准曲线方程,计算其羧基含量,得到的羧基含量与采用国标法测试的羧基含量进行对比,误差在2%~4%之间。为了提高实验的准确度,选取标样绘制标准曲线时,必须保证待测氧化淀粉的羧基含量在标准曲线计算的极限值范围之内,且偏离标准曲线的极限值。与国标法测试羧基含量相比,采用红外测试,方法简单易操作,效率高,准确度好。因此采用红外光谱测试方法对氧化淀粉的羧基含量的预测具有一定重要意义。

In the present study ,the carboxyl content of oxidized starch was determined by FTIR spectroscopy .Standard curve was drawn in which the ordinate was carboxyl content determined by national standard method with the ratio of carbonyl absor-bance to the key of C- H absorbance in FTIR spectroscopy as the abscissa .The ratio of absorbance of unknown oxidized starch tested by FTIR spectroscopy was obtained ,The carboxyl content was calculated by standard curve ,and then compared with the carboxyl content determined by national standard method ,and the deviation is between 2% and 4% .In order to improve the ac-curacy of the experiment ,standard sample was selected to draw standard curve to better ensure that the carboxyl content of theunknown oxidized starch is in the range of standard curve calculation limit ,and deviates from the limit of standard curve .Com-pared with the carboxyl content determined by national standard method ,testing with FTIR spectroscopy is simple ,easy to op-erate ,a

探讨了羧基改性剂对PAE树脂的改性方式、改性剂用量，并对改性PAE树脂进行表征，研究了改性PAE树脂的应用效果．结果表明羧基改性剂可以对PAE树脂进行改性，且改性后提高了PAE树脂的增干强效果．实验结果显示：羧基改性剂对PAE树脂的末端改性优于过程改性；末端改性时，羧基改性剂的较佳引入量为9％；当末端改性后的PAE树脂用量为0．5％时，与改性前相比，能够使纸张干抗张指数提高约11％，湿抗张指数降低约8％，耐折度提高约17％，撕裂指数提高约27％，内结合强度提高约47％．另外，在PAE树脂成品中引入羧基改性剂改性，有利于PAE树脂成本的降低，也有利于损纸的回收．

This paper researched on the modified method of PAE resin with carboxyl modifi-er ,discussed the dosage of modifier ,characterized modified PAE resin and studied the appli-cation of the modified PAE resin .The results showed that carboxyl modifier can undertake modification of PAE resin ,and also improve the effect of the dry strength of PAE resin .Ex-perimental results show that add carboxyl modifier into the PAE resin product is the best process .Modified PAE resin has high dry strength performance and low strong wet strength performance .The better dosage of carboxyl modifier is 9% .When modified PAE resin dosage was 0 .5% ,compared with traditional PAE resin can improve the paper dry tensile index a-bout 11% ,and reduce about 8% wet tensile index ,folding resistance degree increases by a-bout 17% , tearing index increases by about 27% , the bond strength increases by about 47% .The results of this research had a strong reference value on the modified PAE resin study ,exploitation a

采用十六烷基三甲基溴化铵（CTAB）作为表面活性剂修饰羧基化的单壁碳纳米管（SWNT-COOH/CTAB），并对原始单壁碳纳米管（SWNTs）与羧基化修饰的单壁碳纳米管（SWNT-COOH）进行材料学特征比较。通过细胞活力和细胞凋亡实验对SWNTs、SWNT-COOH和SWNT-COOH/CTAB的细胞毒性进行比较。结果表明，羧基化修饰的单壁碳纳米管比原始单壁碳纳米管的毒性小，单壁碳纳米管经羧基化后其毒性降低；浓度及时间曲线显示SWNT-COOH/CTAB的毒性与表面活性剂CTAB相关，CTAB和 SWNT-COOH/CTAB的细胞毒性在低浓度范围内（0.5-25μg/mL）是可接受的。十六烷基三甲基溴化铵修饰的羧基化单壁碳纳米管在低浓度范围（0.5-25μg/mL）内可以较安全地用于生物医学领域。

The cytotoxicities of single-walled carbon nanotubes (SWNTs) and acid purified single-walled carbon nanotubes (SWNT-COOH) were investigated by spectroscopic analysis. Cell viability and cell apoptosis were applied to assessing the cytotoxicity of SWNT-COOH, cetyltrimethyl ammonium bromide (CTAB) and acid purified carbon nanotubes modified with cetyltrimethyl ammonium bromide (SWNT-COOH/CTAB). The results indicate that SWNTs are more toxic than SWNT-COOH. Concentration and time-curve analyses indicate that cytotoxicity of SWNT-COOH/CTAB is more related to the toxicity of the surfactant CTAB. The cytotoxicity effect of CTAB and SWNT-COOH/CTAB is acceptable at low concentrations (0.5-25μg/mL). The cytotoxicity observation suggests that SWNT-COOH/CTAB can safely applied to biomedical field at low concentrations (0.5-25μg/mL).

模拟了两侧包附苯环的碳原子链通过二硫代羧基和硫醇基与金电极（111）面连接组成的分子结的电子输运特性。计算结果表明,锚基团的调制可以改变整个分子器件的电子输运性质。在苯环两侧的锚基团都是二硫代羧基的情况下,在体系电流-电压曲线上发现了新奇的负微分电阻现象;当苯环两侧的锚基团分别为二硫代羧基和硫醇基时,整个体系表现出明显的分子整流效应。

The electronic transport properties of molecular wires made of carbon atomic chains (triynes) capped with benzene are investigated by using nonequilibrium Green′s function in combination with density functional theory. The results show that the anchoring group plays a crucial role in determining the overall conductivity of the molecular junction. Negative differential resistance can be observed when the molecular wire contacts Au electrodes through a dithiocarboxylate linker on both sides, while the rectifying performance is observed when the molecular wire contacts Au electrodes through a thiol linker on one side and with a dithiocarboxylate anchoring group on the other. The mechanisms are suggested for these behaviors.

目的研究羧基磁珠吸附乙型肝炎病毒表面抗原(HBsAg)的性能,为磁珠在蛋白质分离纯化中的应用打下基础。方法检测羧基磁珠吸附HBsAg前后的蛋白量,判断磁珠用量、HBsAg浓度、吸附温度、吸附时间对磁珠吸附HBsAg的影响。使用10mmol/L NaOH洗脱HBsAg,测定洗脱后HBsAg的洗脱率和生物活性保留率。结果羧基磁珠吸附HBsAg的性能与磁珠用量、HBsAg浓度、吸附温度和吸附时间有密切关系。磁珠吸附浓度为524.24μg/mL的血源性HBsAg纯品后,10mmol/L NaOH溶液洗脱HBsAg的洗脱率是71.02%,活性保留率为88.15%。结论带有羧基的磁珠可以吸附HBsAg,有望用于HBsAg的分离回收,为磁珠在蛋白质分离纯化中的应用打下基础。

Objective To lay the foundation for the application of magnetic beads in protein purification by re-searching carboxyl magnetic beads adsorption performance of HBsAg .Methods The amount of magnetic beads ,HB-sAg concentration ,adsorption temperature and the influence of adsorption time by detecting the protein amount be-fore and after adsorption were detected .Results Adsorption HBsAg capacity of magnetic beads was affected by a-mount of magnetic beads ,HBsAg concentration ,adsorption temperature and adsorption time .After magnetic beads adsorption of HBsAg whose concentration was 524 .24 μg/mL ,the adsorbed HBsAg could be eluted by 10 mmol/L NaOH ,the elution rate was 71 .02% ,and the retained biological activity was 88 .15% .Conclusion Magnetic beads with carboxyl can adsorption HBsAg ,which is expected to be used for the separation and recovery of HBsAg .It has lay the foundation for the application of magnetic beads in protein purification.