一种离子交换纤维纸的试制及其主要性质

离子交换纤维素应用于色层分析中具有许多优点,因此在有机化学和生物化学领域中已经获得广泛应用,国外也有各种纤维素粉(和纸)出售。为了适应生产和科学研究的需要,我们利用国产棉质纤维滤纸试制成一种含膦酸基的阳离子交换纤维纸,其基本性质及分离选择性等均表现良好。实验部分 (一)主要试剂与仪器     

电信业务预测的新方法研究

作者主要是讨论电信业务量新的预测方法。在分析了传统的Ｆｉｓｈｅｒ－Ｐｒｙ模型不能对缺乏历史数据的新业务进行有效的预测后，提出了二次起飞模型和替换模型，实际观测结果表明这两种新模型可以较好地解决新业务的预测问题。     

钢铁、矿石等物料中钴的光度法测定

近年来报导了一些高灵敏的钴试剂,如5-Cl-PADAB、PADAT、5-Br-PADAP等,都已广泛用于多种物料中痕量钴的测定。对于样品中0.1%以上钴的测定,常用的亚硝基-R-盐法(ε_(570)=1.5×10~4)和α-亚硝基-β-萘酚法(ε_(317)=2.65×10~4)均嫌其灵敏度不够。作者根据文献报导为基础,合成了3-[(5-溴-2-吡啶)偶氮]-2,6-二氨基吡啶(5-Br-PADAPy)试剂,它对钴有中等灵敏度(ε_(615)=3.91×10~4),适宜用于钢铁、矿石等物料中万分之一以上至百分之一以下的钴的测定。与PADAT等不同,5-Br-PADAPy只含有单一的分析功能团,其选择性较好,它与钴形成的络合物在酸性介质中不分解。方法快速,结果     

Molecular Dynamics Simulation of the Binding Interaction between Hormone Glucagon Protein and Self-Assembled Monolayer Molecules

Restrained molecular dynamics simulations were performed to study the binding affinity of the peptide with alkanethiols of different tail-groups, S（CH2）7CH3, S（CH2）7OH and S（CH2）7COOH, which self-assembled on Au（111） surface in the presence of water molecules. The curves of binding affinity were calculated by fixing the center of mass of the peptide at various distances from the assembling surface. Simulation results show that the binding affin- ity is in the order as COOH-SAMs〉OH-SAMs〉CH3-SAMs, while 100% COOH-SAMs〉5% COOH-SAMS in concentration. The effects on binding affinity by different tail-groups were also studied. Results show that the binding affinity between COOH-SAMs and the peptide is bigger than those of the others and increasing the acidity of COOH-SAMs will result in stronger attractive power.     

理论面积的环面简易展开法—比例圆法

本文从理论上研讨了如何在环面展开图中能得到环面理论面积的展开方法,由此提出一种既能得到环面展开理论面积,作图又很简便的圆环面展开法——比例圆法,分析了比例圆法与圆柱面法展开圆环面之间的差异,并说明了用比例圆法也可非常方便地获得圆柱面法展开圆环面时的图形.     

宽带场强测试仪电路的研究

研制了 4种高灵敏度、宽通频带的测量空间杂散电磁场电路 ,即晶体管电路、结型场效应管电路、绝缘栅场交应管电路及复合管电路 ,并进行实验测试 .经测试 ,这些电路可靠、实用     

双分子水和氨气催化CF3OH分子裂解的理论研究

The G3 and CBS-QB3 theoretical methods are employed to study the decomposition of CF₃OH into FCFO and HF by water, water dimmer, and ammonia. The decomposition of CF₃OH into FCFO and HF is unlikely to occur in the atmosphere due to the high activated energy of 88.7 kJ/mol at the G3 level of theory. However, the computed results predict that the barrier for unimolecular decomposition of CF₃OH is decreased to 25.1 kJ/mol from 188.7 kJ/mol with the aid of NH₃ at the G3 level of theory, which shows that the ammonia play a strong catalytic effect on the split of CF₃OH. In addition, the calculated rate constants show that the decomposition of CF₃OH by NH₃ is faster than those of H₂O and the water dimmer by 109 and 105 times respectively. The rate constants combined with the corresponding concentrations of these species demonstrate that the reaction CF₃OH with NH₃ via TS4 is of great importance for the decomposition of CF₃OH in the atmosphere.     

近红外光谱测定猪眼肌肌内脂肪中脂肪酸含量

为了快速无损测定猪眼肌肌内脂肪中脂肪酸含量,提出了近红外光谱技术检测的新方法。选用气相色谱法作为猪眼肌肌内脂肪中脂肪酸测定的标定方法,采用漫反射光纤探头采集由低密度聚乙烯塑料袋包装的猪眼肌样品的光谱,来测定眼肌内脂肪中脂肪酸的含量。利用光谱专用分析软件Unscrambler9.6, 对采集的光谱用平滑,二阶微分法进行预处理, 用偏最小二乘法(PLS)建立其定量检测模型。用于本实验的样本总数为82,将异常点除去后,将样品分为校正集和检验集。用校正集的样品来建立定标方程,再用它来预测检验集样品的值。结果表明,脂肪酸C14∶0,C15∶1,C16∶0,C16∶1,C18∶0,C18∶1,C18∶2,C18∶3,C20∶1,C20∶4,SFA,MUFA和PUFA校正模型的相关系数分别为0.57,0.76,0.71,0.77,0.62,0.81,0.86,0.91,0.85,0.91,0.67,0.81和0.95。可见, 用该方法测定肌内脂肪中脂肪酸有较高的测定精度,因此,应用近红外光谱对猪眼肌肌内脂肪中脂肪酸含量的快速无损检测具有可行性。     

小样本光子图像的统计处理

讨论了一种对小样本光子图像的统计处理方法。在超微弱发光的研究中（例如细胞的超微弱荧光）,由于发光强度极弱,需要用像增强器对超微弱发光图像进行增强得到可视图像,超微弱发光图像不可避免地受到像增强系统暗噪声及背景噪声的影响,使光子图像湮没在噪声中。为从原始图像中检验出信号,根据信号光子和噪声光子的不同统计分布,运用信号检测与的方法判断光子是否属于信号光子,并得到一简明的判据,由此判据剔除图像中的噪声光子,得到信噪比改善的光子图像。并用此方法处理了人掌的超微弱发光光子图像。     

第—代农民工返乡的影响因素分析

八十年代初到九十年代初外出打工的农民工可被称为第一代农民工。当前,这批农民工中的许多人因年龄等原因面临着返乡的必然选择。对其返乡的影响因素与返乡后的安置问题进行研究,关系到他们的民生,关系到社会主义新农村的建设。