碳60分子模型的简易制作方法

碳60的发现是荣获了1996年诺贝尔化学奖的重大贡献,将我们带进了又一个化学新世界。实践中碳60分了的独特构型引起了中学化学教师和学生的极大兴趣,但尚缺少其分了模型的简易制作方法。作者在教学过程中创造了一种碳60分了模型的制作方法。     

储氢合金电极的表面修饰研究

利用等离子体技术对AA型MH/Ni电池的储氢合金电极进行了镀覆导电膜层的表面修饰,用XRD及SEM对电极结构进行了表征.极片经过表面修饰的电池,其内阻降低了24％,放电容量有了明显提高,5C (7.5 A) 放电容量提高了200 mA•h,放电平台电压提高了约0.14 V,导电膜层还起到了电极保护层的作用,抑制了合金的粉化,提高了电池的循环稳定性.同时,电池内压显著降低,电池性能有了较大改善.     

Design of a PFW European type impact crusher

介绍了一种PFW欧版反击式破碎机,由于该机采用了重型转子装置,取得了较好的破碎效果。该破碎机结构科学合理,使用安全可靠,维护方便快捷。与传统反击式破碎机相比,不仅延长了设备的使用寿命,缩短了耐磨件的更换时间,而且提高了生产效率,增加了经济效益。     

促进学生认识发展的“电离和离子反应”专题的单元整体教学研究

系统梳理了电离、离子反应专题的已有研究,分析了电离、离子反应内容对学生认识发展的作用,进而确立了化学1模块电离、离子反应专题的教学论问题并进行了阐述分析。在上述研究的基础上,设计了化学1模块电离、离子反应专题的单元整体教学,并进行了教学实践,取得了较好的教学效果。     

乙酰乙酸乙酯－BR化学振荡反应的研究

本文首次报道了乙酰乙酸乙酯－ＩＯ－３－Ｈ２Ｏ２－Ｍｎ２＋－Ｈ２ＳＯ４体系的化学振荡反应。研究了各种因素对振荡反应的影响，测定了最佳反应条件及振荡反应的浓度范围。研究了温度变化对振荡反应的影响，并计算了振荡反应的表观活化能，对振荡反应产物进行了分析，并测定了体系主要反应的计量关系，采用ＵＶ法对金属离子的作用和催化机理作了研究，探索了ＢＲ反应中Ｉ２的产生机理及消耗机理，对体系中有关反应物的作用作了说明。在ＦＫＮ机理的基础上，对ＢＲ反应的自催化反应步骤和控制机理进行了初步的探索，并对有关实验现象作了说明。     

低维ZnO纳米材料

本文主要综述了近年来ZnO纳米材料制备领域的一些新方法,简单比较了各种方法之间的优缺点;讨论了制备不同形貌的ZnO纳米材料的影响因素,其中重点讨论了表面活性剂的作用;介绍了ZnO纳米材料的性质及其可能的应用领域;并对ZnO纳米材料的发展前景进行了展望。     

前言

自20世纪初期,德国化学家EmilFischer首先合成了甘氨酸二肽片段,并第一次提出“peptide”（多肽）这一名词,多肽化学的研究已经历了100多年的发展．1953年,Vigneand小组首次完成了生物活性肽催产素的合成,并因此于1955年获得了诺贝尔化学奖．1963年,Merrifield提出了多肽固相合成法,并发明了第一台多肽自动合成仪,大大简化了多肽合成的流程、提高了合成的效率,从而促使多肽化学实现了飞跃式发展,Merrifield也因此获得了1984年诺贝尔化学奖．1965年,我国科学家完成了牛结晶胰岛素的合成,     

基于经典实验的教学改革模式探讨——以二元液系气液平衡相图实验的改进为例

从实验装置、实验体系、溶液配制、数据测量等方面针对经典的物理化学实验(二元液系气液平衡相图)进行了综合性探索。减少了实验试剂消耗,缩短了实验时间,改善了实验的操作性和重现性,同时消除了实验过程中的安全隐患。经过多年工科专业学生实验教学实践表明,这些改进措施提升了学生的低碳环保理念,改善了实验的过程体验,强化了经典实验的创新效果。在引导学生深刻理解气液相平衡基础理论的同时培养了学生的应用创新思维,获得了良好的实验教学效果。     

无机化学微信平台的构建与实践研究

针对无机化学传统教学模式的不足,构建了无机化学微信平台。介绍了构建平台必需的微信公众号和微信群的建立过程和方法。分析了无机化学微信平台在教学中的实践效果,弥补了传统教学中的不足。讨论了无机化学微信平台的积极作用,提高了教师教学水平和学生的学习能力,达到了师生双赢的目的。     

稀土抛光粉的生产及应用

综述了稀土抛光粉的各种制造工艺及其在玻璃抛光领域的应用现状，以稀土抛光粉不同的化学成分，粒度，用途等对稀土抛光粉进行了归纳分类，介绍了国内外稀土抛光粉生产企业的产生规律，产品特点，对国内外稀土抛光粉的制备工艺流程进行了归纳，阐述了稀土抛光粉的抛光工艺及抛光机理，重点讨论了稀土抛光粉的应用领域，预测了稀土抛光粉市场的未来，对稀土抛光粉的应用进行了展望。     

DNA and RNA sensor

The development of DNA sensors attracts recentresearch attention directed at gene analysis, such asdetection of genetic disorders, tissue matching andforensic applications[1,2]. In general, sensors based on the principle differ-ent from that of the tr…     

Progress in oscillographic chronopotentiometry

This review summarizes recent advances in DNA sensor. Major areas of DNA sensor covered in this review include immobilization methods of DNA, general techniques of DNA detection and application of nanoparticles in DNA sensor.     

Sequence-specific detection of femtomolar DNA via a chronocoulometric DNA sensor (CDS): effects of nanoparticle-mediated amplification and nanoscale control of DNA assembly at electrodes

We herein report a novel nanoparticle-based electrochemical DNA detection approach. This DNA sensor is based on a "sandwich" detection strategy, which involves capture probe DNA immobilized on gold electrodes and reporter probe DNA labeled with gold nanoparticles that flank the target DNA sequence. Electrochemical signals are generated by chronocoulometric interrogation of [Ru(NH(3))(6)](3+) that quantitatively binds to surface-confined capture probe DNA via electrostatic interactions. We demonstrated that the incorporation of a gold nanoparticle in this sensor design significantly enhanced the sensitivity and the selectivity. Nanoscale control of the self-assembly process of DNA probes at gold electrodes further increased the sensor performance. As a result of these two combined effects, this DNA sensor could detect as low as femtomolar (zeptomoles) DNA targets and exhibited excellent selectivity against even a single-base mismatch. In addition, this novel DNA sensor showed fairly good reproducibility, stability, and reusability.     

γ-干扰素DNA传感器组装过程的表面等离子体子共振研究

自行设计并组装了一套简便实用的多波长表面等离子体子共振DNA传感装置,用于γ-干扰素DNA的检测。以人工合成γ-干扰素(interferongamma,IFN-γ)寡聚核苷酸片段作为DNA探针,用化学法标记生物素探针,利用生物素-亲和素系统相互作用在传感器表面固定DNA探针,使用该SPR传感装置实时监测了DNA探针的固定过程及DNA杂交反应的进行。用于IFN-γ寡聚核苷酸的检测,测定范围为50-400ng/mL;用于IFN-γ的聚合酶链反应(polymerasechainreaction,PCR)扩增产物的检测,其测定范围为5-40ng/mL。同时研究了DNA传感器的稳定性、可逆性及干扰情况。实验结果表明,该传感器可成功地用于检测目的DNA。     

血清样品中乙肝病毒的DNA电化学传感器检测

利用自组装单分子膜技术，将巯己基修饰的具有乙肝病毒(HBV)DNA序列特异性的单链DNA探针固定在金电极表面，制得DNA电化学传感器；以电活性的Hoechst 33258为指示剂，考察了该传感器对血清样品中乙肝病毒DNA的响应；探讨DNA电化学传感器在临床检测中的应用；将传感器法与荧光聚合酶链反应(PCR)法进行对比，两者的分析结果具有一致性。     

A potentiometric DNA sensor for determining autoimmune antibodies to DNA

A new technique is proposed for detecting interactions between DNA and DNA autoimmune antibodies using a potentiometric sensor based on a glassy-carbon electrode modified with polyaniline and native DNA from chicken erythrocytes. It is shown that the DNA-antibody interaction changes the rate of polyaniline doping in transferring the DNA sensor from an alkaline (pH 7.5) solution, which is optimum for the immunochemical reaction, to an acidic (pH 3.0) solution. The dynamics of the variation of the DNA sensor potential depends on the titer of antibodies and their origin. The dependence of the DNA sensor signal on the dilution of the blood sera from systemic lupus erythematosus and autoimmune thyroiditis patients shows that DNA antibodies can be diagnosed by the characteristic maximum in the dilution curve found in the range of serum dilutions from 1: 20 to 1: 50.     

Amperometric detection of DNA hybridization on a gold surface depends on the orientation of oligonucleotide chains

We tested the possibility of amperometric detection of DNA hybridization on a gold surface influenced by the immobilization of oligonucleotide giving different orientations of single stranded DNA relative to the gold surface. The DNA sensor was fabricated by chemisorption of 18-mer oligonucleotide modified by a phosphorothioate group either at its 3' or both 3' and 5' terminal. After immobilization of oligonucleotide to the gold support, the sensor was immersed in 11-mercaptoundecanoic acid (MUA) solution. Further chemisorption of MUA resulted in approximately 10-fold increase of resistance of the organic layer. Addition of complementary oligonucleotide resulted in an increase of conductivity for DNA sensor oriented perpendicular to the gold support (DNA with one thiol group), while the conductance decreased for DNA sensor with single stranded DNA oriented parallel to the gold support (with DNA modified by thiol groups at both 3' and 5' terminals). Addition of non-complementary chain resulted a slight decrease or no change of sensor conductivity. The hybridization process at both types of DNA orientations is not cooperative and can be described by Langmuir isotherms. The hybridization event on gold support has been confirmed by mass detection using the quartz crystal microbalance technique.     

Electrochemical sensor for blood deoxyribonucleases: design and application to the diagnosis of autoimmune thyroiditis

We designed an electrochemical sensor based on a carbon nanotube modified electrode (ME) to analyze DNA-cleaving activity. The cleavage of high molecular weight DNA resulted in an increase in the oxidation current from DNA guanine nucleotides due to a change in DNA adsorptive behavior on the surface of the ME. DNA digestion with DNAse I was accompanied by a linear increase in the DNA signal in proportion to the enzyme activity. We then proposed an assay based on the sensor for the direct assessment of the total deoxyribonuclease activity of blood serum as well as the separate detection of DNAse I and DNA abzymes. The assay was applied to analyze deoxyribonucleases in sera from 21 healthy donors and 17 patients with autoimmune thyroiditis. Our results show that the response of the sensor to DNA cleavage by blood deoxyribonucleases is a promising diagnostic criterion for autoimmune thyroiditis. This sensor can be implemented in a disposable screen-printed electrode format for application in clinical laboratories.     

The Use of Xenonucleic Acids Significantly Reduces the In Vivo Drift of Electrochemical Aptamer-Based Sensors

Electrochemical aptamer-based sensors support the high-frequency, real-time monitoring of molecules-of-interest in vivo. Achieving this requires methods for correcting the sensor drift seen during in vivo placements. While this correction ensures EAB sensor measurements remain accurate, as drift progresses it reduces the signal-to-noise ratio and precision. Here, we show that enzymatic cleavage of the sensor's target-recognizing DNA aptamer is a major source of this signal loss. To demonstrate this, we deployed a tobramycin-detecting EAB sensor analog fabricated with the DNase-resistant “xenonucleic acid” 2’O-methyl-RNA in a live rat. In contrast to the sensor employing the equivalent DNA aptamer, the 2’O-methyl-RNA aptamer sensor lost very little signal and had improved signal-to-noise. We further characterized the EAB sensor drift using unstructured DNA or 2’O-methyl-RNA oligonucleotides. While the two devices drift similarly in vitro in whole blood, the in vivo drift of the 2’O-methyl-RNA-employing device is less compared to the DNA-employing device. Studies of the electron transfer kinetics suggested that the greater drift of the latter sensor arises due to enzymatic DNA degradation. These findings, coupled with advances in the selection of aptamers employing XNA, suggest a means of improving EAB sensor stability when they are used to perform molecular monitoring in the living body.     

Rapid DNA hybridization analysis using a PDMS microfluidic sensor and a molecular beacon.

A rapid DNA analysis has been developed based on a fluorescence intensity change of a molecular beacon in a PDMS microfluidic channel. Recently, we reported a new analytical method of DNA hybridization involving a PDMS microfluidic sensor using fluorescence energy transfer (FRET). However, there are some limitations in its application to real DNA samples because the target DNA must be labelled with a suitable fluorescent dye. To resolve this problem, we have developed a new DNA microfluidic sensor using a molecular beacon. By monitoring the change in the restored fluorescence intensity along the channel length, it is possible to rapidly detect any hybridization of the molecular beacon to the target DNA. In this case, the target DNA does not need to be labelled. Our experimental results demonstrate that this microfluidic sensor using a molecular beacon is a promising diagnostic tool for rapid DNA hybridization analysis.