Adsorption separation performance of H2/CH4 on ETS-4 by concentration pulse chromatography

To exploit an effective adsorbent to separate hydrogen and methane, microporous titanium silicate molecular sieve NaETS-4 was synthesized and modified by strontium. The adsorption characteristics and diffusion behaviors of the prepared titanosilicate molecular sieve were studied by concentration pulse chromatography. And the effects of ion-exchange and dehydration temperature on adsorbent structure and gas diffusion were also discussed. The results showed that the thermal stability and Henry＇s Law constants were enhanced and micropore diffusivity decreased after exchanging Na＋ with Sr2＋. With the increase of dehydration temperature, Henry＇s Law constant and micropore diffusivity of CI-I4 decreased in both NaETS-4 and SrETS-4. While for 1-12 in SrETS-4, the increase of Henry＇s Law constant and the decrease of diffusion rate can be attributed to the shrinks of pore diameter resulting from the relocation of Sr2＋. Correspondingly, the kinetic selectivity of H2/CH4 reached 8.91 indicating its potentiality in separating H2 and CH4.     

岩石抽提物中极性化合物超高分辨质谱识别

采用具有超高分辨率的负离子电喷雾-傅立叶变换离子回旋共振质谱（ESI FT-ICR MS）分析了储层岩石抽提物中的石油酸及中性氮化物的分子组成,得到了抽提物中杂原子化合物类型分布、等效双键数（Double bonds equivalent,DBE）及碳数分布特征。研究结果表明,储层抽提物中含有多达16种不同杂原子类型的化合物,包括N1、N1O1、N1O2、N1O3、N1S1、N1S2、N2、N2S1、O1、O1S1、O2、O2S1、O1S2、O2S2、O3和O4,其中N1、N1S1、O2及O2S1类具有较高的相对丰度。抽提物中的N1类化合物以咔唑和苯并咔唑类化合物为主;N1S1类化合物以C2~C8烷基取代的咔唑并苯并噻吩类化合物为主;O2类化合物主要为1~2环环烷酸,其次还在抽提物中鉴别出具有较高相对丰度的DBE为5和6的O2类化合物;而O2S1类化合物中以DBE为7和8的O2S1具有最高的相对丰度。     

分析测试新成果(238~242)电线塑料护套的傅立叶变换红外光谱分析

采用傅立叶变换红外光谱法对21个5种不同颜色的电线塑料护套样品进行了分析.从红外光谱图中可观察到样品特征峰的峰数、峰位、相对峰面积比均有差异,但可以归纳为两大类.其中同种颜色的不同样品在红外谱图中又反映出了不同的信息,这表明在外观颜色十分相近的情况下,采用此方法能够有效的为刑事案件现场遗留的各种塑料制品提供鉴别与比对.     

自制光电比色计及其在中学化学实验中的应用

针对大多数中学缺乏光电比色计和分光光度计的现状,基于朗伯比尔定律和3D打印技术自制光电比色计,测定透明有色溶液的吸光度和浓度。利用自制光电比色计测定了琥珀酸亚铁片中铁的含量和硫酸铜晶体中结晶水的含量,实验结果表明自制光电比色计的精度高、准确性好。将3D打印技术引入化学实验创新改进,体现了跨学科融合和创新设计的思想。     

Bifurcation Control of Current-Mode Buck Converter via TDFC

Considering the TDFC controlled current-mode Buck converter featuring periodicity we propose a Fourier-decomposition based method for the bifurcation analysis of this system, hence the theoretical range of control gain of TDFC is determined. In addition, the power-stage experiment circuit is built and the control part is realized in a digital controller. The experimental results show that either bifurcation or chaos in the current-mode Buck converter can be controlled into the expectant period-1 orbit rapidly.     

正确理解“外界做功”

一位青年教师在讲授完"热力学第一定律"的相关知识后,为使学生加深对该定律的理解,设计了下面一道练习题.     

一种邻近性的计算方法

邻近律是Gestalt定律的基本定律之一，然而迄今为止，如何在图像处理中计算元素之间的邻近性程度还没有具体方法提出．以点元素作为抽象载体提出了一种邻近性的计算方法，该方法借鉴基于最小支撑树（MST）的聚类思想，引入三角剖分和Prim算法计算元素之间的MST邻近性测度和加权MST邻近性测度用于度量元素之间的邻近性．实验结...     

“万有引力定律”教学中的两个“困惑”

在处理现行人教版高中《物理》"万有引力定律"相关内容的教学时,师生都感到某些"困惑";通过查阅大量资料和反复思考,这些"困惑"得到解决.     

On the order of summability of the Fourier inversion formula

In this article we show that the order of the point value, in the sense of Łojasiewicz, of a tempered distribution and the order of summability of the pointwise Fourier inversion formula are closely related. Assuming that the order of the point values and certain order of growth at infinity are given for a tempered distribution, we estimate the order of summability of the Fourier inversion formula. For Fourier series, and in other cases, it is shown that if the distribution has a distributional point value of order k, then its Fourier series is e.v. Cesàro summable to the distributional point value of order k+1. Conversely, we also show that if the pointwise Fourier inversion formula is e.v. Cesàro summable of order k, then the distribution is the (k+1)-th derivative of a locally integrable function, and the distribution has a distributional point value of order k+2. We also establish connections between orders of summability and local behavior for other Fourier inversion problems.