Gas concentration detection based on LabVIEW and laser technique

本文针对目前用光电技术检测气体浓度存在精度较低、可靠性较差等问题,提出了一套新的光电检测气体浓度的方案。该方案基于迈克尔逊干涉仪在不同的气体中光程差的不同,会导致干涉条纹的移动和强度的变化的原理,采用激光双光路干涉法其中一路干涉光参考,一路光测量,通过两路干涉条纹的比较,消除系统误差和外界环境干扰,提高测量精度。实验利用UNIQ UM201的CCD和PCI总线的图像采集卡在LabVIEW环境下采集干涉条纹,并对采集到的图像进行数据处理,在外界微弱的变化下,图像发生改变,该实验方案有很高的灵敏度和响应速度。Based on the principle that the position and intensity of Michelson interference fringes change due to different optical path lengths in different gases,a new system is designed,which applies two interferometers,one is used for test and the other is used as reference.The problems of low precision and bad reliability existing in detecting gas concentration are solved.In this system UNIQ UM201 Charge Coupled Device and Matrox Meteor-II image grab card are used to acquire the interference fringes and the images of the obtained fringes are processed in the LabVIEW environment.As the surroundings change faintly,the images will also change,and this test scheme has high sensitivity and fast response

Preparation of Chitosan Magnetic Microspheres

用共沉淀法制备Fe3O4磁性纳米粒子,并对其用油酸进行表面改性,继而采用沉淀聚合法制备壳聚糖磁性微球。考察了沉淀剂浓度、乳化剂种类、Fe3O4的改性等条件对制备微球的影响。应用扫描电镜、红外谱图、接触角仪、粒径分析仪及磁铁吸附对壳聚糖磁性微球的形态与特性进行了表征。研究结果表明,在适宜的沉淀剂浓度、复合乳化剂、Fe3O4经油酸改性等条件下,可以制得平均粒径为150 nm、单分散性好且磁性明显的壳聚糖磁性微球。The Fe3O4 nanoparticles were prepared by co-precipitation method and modified by oleic acid.Chitosan magnetic microspheres were then prepared by precipitation polymerization method.The results demonstrated that the concentration of the precipitant,the type of emulsion and the modification of the iron oxide were the most effective parameters for the preparation of the microspheres.The SEM,IR and DLS results indicated that the diameter of the microspheres was about 150nm and the microspheres were uniformly distributed.The magnetic test showed the microspheres were magnetic sensitive.国家自然科学基金(50573063);; 教育部新世纪优秀人才计划项目;; 高等学校博士点专项基金(2005038401);; 厦门大学人才基金(0000X071C1

关于强化电子教参系统服务的思考——兼析厦门大学电子教参系统用户调研

[目的/意义]我国不少图书馆都开展了电子教参系统建设,但因不同系统的资源和功能差异较大,因而取得的成效也各不相同。文章通过回顾我国电子教参系统的建设历程,并结合厦门大学图书馆教参系统的调研分析,指出建设过程中应改进的某些不足与欠缺,提出强化功能、提高成效的举措,供相关机构参考借鉴。[方法/过程]利用"问卷星"开展网上问卷调研,分析回收的问卷,了解用户利用电子教参系统的偏好、功能需求及改进意见等,结合文献调研及定性分析,思考强化电子教参系统服务的对策。[结果/结论]厦门大学图书馆电子教参系统的调研结果表明,该系统总体上较受欢迎,但系统的资源有待充实,图书馆宣传有待加强,网上答疑和用户交互体验等功能有待完善。文章最后提出提高电子教参系统服务成效的思路:丰富资源,完善功能,尤其注重图书馆电子教参系统与学校选课系统及其他相关平台的无缝融合,同时要加强宣传,共享资源。2017年福建省中青年教师教育科研项目“教育信息化背景下的高校电子教参资源建设和服务研究”（项目批准号JAT170152）的阶段性研究成果之

Production and consumption of dimethyl sulfur compounds by three typical algae

采用抑制剂加入法估算了中肋骨条藻、棕囊藻和东海原甲藻在不同生长期内二甲基硫化物的产生与消耗速率.结果表明:颗粒态二甲基巯基丙酸(DMSPp)和颗粒态二甲亚砜(DMSOp)在3种藻类的不同生长期内均为净消耗,溶解态二甲基巯基丙酸(DMSPd)和溶解态二甲亚砜(DMSOd)的含量受藻类产生与细菌病毒消耗控制,在藻类不同生长期内存在不同的产生与消耗速率,而二甲基硫(DMS)在3种藻不同生长期内均为净产生.同一种藻在不同生长期内以及不同藻在相同生长期内二甲基硫化物的产生与消耗速率均存在较大差异,表明藻类的生理状态和种间差异均对二甲基硫化物的产生与消耗速率产生影响.By the method of inhibitor amendment, this paper estimated the production and consumption of dimethyl sulfur compounds by Skeletonema costatum, Phaeocystis sp. and Prorocentrum donghaiense in their different growth phases. The results indicated that throughout the whole growth period of the three algae, particle dimethylsulfoniopropionate (DMSPp) and dimethylsulfoxide (DMSOp) were net consumed. The concentrations of dissolved dimethylsulfoniopropionate (DMSPd) and dimethylsulfoxide (DMSOd) were mainly affected by the processes of algal production and bacterial and virus consumption, and thus, could reflect their production or consumption rates in the growth period of algae. Dimethylsulfide (DMS) was net produced in the whole growth period of the algae. There was a greater difference in the production and consumption of dimethyl sulfur compounds for the same alga in its different growth phases and for different algae in the same growth phase, indicating that both the physiology and the inter-species difference of algae had effects on the production and consumption of dimethyl sulfur compounds.国家自然科学基金资助项目(200077022

Data acquisition system based on LabVIEW for array sensors

本文介绍了以单片机进行数据采集,LabVIEW为开发平台,两者之间通过串口进行通信的多通道数据采集系统。该系统可对低频传感器信号进行采集、显示和存储。文中详细介绍了软、硬件设计方案和测试结果。This paper describes a data acquisition and display system based on LabVIEW platform and AT89S51 Microcontroller, which communicate with each other via RS232 interface, using user-defined communication protocol to ensure communication efficiency and stability. The system adopts MAX197 A/D converter, which acquires 0～+ 10V voltage signals through 6 analog input channels with 12-bit resolution. And the MCU is programmed with Assembly Language. LabVIEW carries out the management tasks, including the data acquisition control, Serial Port Communication control, display and storage of available data. The system, which has low cost and good performance, has been tested and reflects easy operation, good stability and reliability

Experimental studies on treating humid acid solution by photocatalytic oxidation

以腐殖酸类物质作为废水中有机物的代表,研究了水体中腐殖酸在纳米TIO2颗粒上的吸附行为及以此为催化剂对水中腐殖酸进行的光催化氧化行为。考察了不同催化剂质量浓度、初始PH值、腐殖酸初始质量浓度等因素对腐殖酸去除率的影响。结果表明:腐殖酸在TIO2颗粒上的平衡吸附量对溶液的初始PH值依赖性很小;初始PH值降低、腐殖酸初始质量浓度减小,均能显著提高腐殖酸的去除率。同时将光催化氧化与单纯紫外线照射的去除率作对比,光催化氧化法明显优于单纯紫外线照射。Humid acid(HA) is the representation of organic matter in wastewater.The behaviors of adsorption and photocatalytic oxidation of HA in water on TiO2 particles were studied.The effects of different factors on removal of HA from water were investigated,such as mass concentration of catalyst,initial value of pH,initial mass concentration of HA,etc.The results show that the adsorption amount of HA in balance on TiO2 particles is independent of initial pH value of the solution.The removal efficiency of HA is improved greatly with the decreasing of initial pH value and initial mass concentration of HA.Comparing the removal efficiency of photocatalytic oxidation with that of ultraviolet radiation alone,the photocatalytic oxidation is better than ultraviolet radiation alone.厦门大学人才引进基金项目(0000X071C1

Effect of NaCl Stress on Physiological Characteristics of Two Manilkara Species Leaves

采用盆栽试验法,对铁线子属果树人心果[MAnIlkArA zAPOTA(l.)VAn rOyEn]和古巴牛乳树[MAnIlkArA rOXburgHIAnA(WIgHT)dubArd]进行nACl胁迫处理,测定叶片的叶绿素、超氧化物歧化酶(SOd)、过氧化物酶(POd)、过氧化氢酶(CAT)、游离脯氨酸、可溶性蛋白等指标及盆土的实际盐度。结果表明,人心果在盐度1.98‰以内、古巴牛乳树在盐度2.42‰以内没有盐害;在nACl胁迫下,两树种的叶绿素合成受到明显抑制;随着处理浓度增加,人心果叶片的SOd活性升高,各处理浓度下的活性都显著高于对照,但POd和CAT活性呈现先升后降趋势,古巴牛乳树叶片的CAT活性升高,但SOd和POd活性降低,三者活性在各处理浓度下都显著高于对照;人心果叶片的脯氨酸含量在各处理浓度均显著高于对照,可溶性蛋白含量在处理浓度为4‰及以上时显著高于对照,古巴牛乳树叶片的脯氨酸、可溶性蛋白在处理浓度为4‰及以上时显著高于对照,推测脯氨酸、可溶性蛋白作为渗透调节物质在人心果、古巴牛乳树受nACl胁迫过程中起着重要的作用。The physiological characteristics of Manilkara zapota(L.)van Royen and Manilkara roxburghiana(Wight)Dubard were studied by watering the potted plants with NaCl solution.The characteristics include chlorophyll,proline,soluble protein,SOD,POD,CAT and so on.The results showed that Manilkara zapota(L.)van Royen grew well below 1.98‰ NaCl stress condition,so did Manilkara roxburghiana(Wight)Dubard below 2.42‰ NaCl stress condition.Under NaCl stress,chlorophyll synthesis was significantly restricted;For Manilkara zapota(L.)van Royen,the activity of the SOD increased,however the activity of POD or CAT increased first and then dropped.The content of proline was higher significantly than that of the control,so did the content of soluble protein when the concentration of NaCl was between 4‰--8‰.For Manilkara roxburghiana(Wight)Dubard,the activity of CAT increased and that of SOD or POD decreased.The activities of the SOD,POD and CAT differed significantly from that of the control.The content of proline or soluble protein was higher than that of the control when the concentration of NaCl was between 4‰--8‰.The small organic molecules working as osmotic potentials in cells played a key role in salt tolerance for the two species.厦门市科技计划项目(No.3502Z20092023

Progress in the studies of vivipary in mangrove plants

【中文摘要】植物胎生是指有性繁殖产生的后代在母体上直接萌发的现象, 在红树植物中最为常见。红树植物生长在热带亚热带海岸潮间带, 耐受高盐、高温、淹水缺氧和海浪冲击等复杂环境。胎生被认为是红树植物对这种特殊生境的重要适应方式。 该文从形态发育、生理生化、分子水平、生态适应4个层次讨论红树植物胎生现象对复杂生境的适应性, 并指出现有研究存 在的不足, 对将来的研究方向进行了展望。与非胎生胚胎发育相比, 红树植物胎生是一个遗传的程序, 在进化过程中形成了 一些特殊的结构。植物激素对胎生发育起关键的调控作用, 繁殖体发育过程中, 其盐离子的种类与浓度的动态变化则是对海 岸潮间带生境的重要适应特征。这种胎生繁殖体依靠在母体上完善的一系列功能性特征能更有效地适应落地后的滩涂环境。 然而, 红树植物胎生发育过程的分子机理及调控机制还有待研究。理解胎生这一特殊适应性现象的本质及其进化过程将为红 树林保护繁育、适应气候变化提供理论依据。 【Abstract】Vivipary in plants refers to a phenomenon that sexually reproduced offsprings germinate while still attached to the maternal bodies. This is mostly manifested in mangrove plants, which occur in tropical and subtropical intertidal zones and encounter harsh environmental conditions such as high salinity, high temperatures, waterlogging, hypoxia and tidal waves. Vivipary has long been recognized as one of the most important adaptive features under such a complex environment. Here we discuss four aspects of vivipary: morphological anatomy, physiology and biochemistry, molecular biology and ecological adaptation. We also discuss shortcomings in current studies and prospect of future directions. Differing from regular seed development, viviparous seeds in mangroves are evolved with many special structures, indicating a genetically based process. Hormones play an important role in regulating the process, whilst the dynamics of salt ion concentration during embryo and propagule development seems to be an adaptive feature. The ecological significance of vivipary is fully exhibited in the propagules that can effectively establish themselves on muddy tidal zones. Such a success heavily relies on sound functional features developed on the mother plants. However, the molecular mechanism and the regulation of viviparous seed development in mangroves remain elusive. Systematic studies of vivipary in mangroves not only help to understand the nature and evolutionary process of this distinct adaptive phenomenon, but also provide the foundation for mangrove forest restoration and protection in many parts of the world.福建省对外合作项目(2016I0013

Purification of Multi-Walled Carbon Nanotubes

用 90 0℃高温氢气处理以及 5mol/L盐酸回流的方法 ,纯化了一种由甲烷在Ni—Mg—O催化剂上裂解生长的多壁碳纳米管 (MWCNTs) ,考察了不同纯化阶段MWCNTs的吸水率、比表面积、Ni和Mg残留量以及在不同温度下苯、正己烷、乙醇、丙酮四种化合物在MWCNTs填充色谱柱上的脱附率的变化 ,并用透射电镜观察了MWCNTs的形态 .结果表明 ,高温氢气处理可去除MWCNTs的无定形碳和表面极性基团 ,使其比表面积和吸水率减小 ,同时可打开MWCNTs端口 .高温氢气处理后 ,再用盐酸回流即容易去除MWCNTs中单用盐酸回流方法无法去除的Ni.经过纯化的MWCNTs的吸水率远小于活性碳 ,比CarbopackB稍大 ,比表面积和CarbopackB相近 .苯、正己烷、乙醇、丙酮四种化合物在纯化的MWCNTs填充色谱柱上的脱附率和CarbopackB的相同 .经纯化的MWCNTs的Ni残留量为 3 0 μg/g ,Mg残留量低于检测限 (10 μg/g) .由于管腔的存在 ,纯化的MWCNTs对有机物的保留能力大于CarbopackB .它可以作为气相色谱固定相和吸附挥发性有机物的吸附剂Multi walled carbon nanotubes (MWCNTs), prepared by catalytic decomposition of methane, were purified sequentially with hydrogen gas at high temperature (900 ℃) and hydrochloric acid (5 mol/L) reflux. The variations of surface area, water absorbing capacity, amount of Ni and Mg residuals of the MWCNTs in different purification steps were investigated. The desorbing ratios of benzene, n hexane, ethanol, acetone on columns packed with the MWCNTs in different purification steps were also investigated. The morphologies of the MWCNTs in different purification steps were studied with TEM. The results suggest that the treatment of hydrogen could remove the amorphous carbon and the polar groups on MWCNTs, resulting in the decrease of surface area and water absorbing capacity and having the ends of MWCNTs cut. After the treatment of hydrogen, it was very easy to remove Ni residual in MWCNTs, which could not be removed by hydrochloric acid reflux only. The water adsorbing capacity of the purified MWCNTs was much lower than that of activated charcoal, slightly higher than that of Carbopack B. The surface area of the purified MWCNTs was similar to that of Carbopack B. The desorption ratios of benzene, n hexane, ethanol, acetone on column packed with the purified MWCNTs were the same as those of Carbopack B. The amounts of Ni and Mg remained on the purified MWCNTs were 30 μg/g and were not detected (<10 μg/g), respectively. Due to its hollow cavities inside, the purified MWCNTs have stronger retention ability than Carbopack B. The purified MWCNTs are found to be a suitable packing material for gas chromatography and a sorbent in trapping volatile organic compounds from air.国家自然科学基金 (No.2 0 0 770 2 2 );; 教育部重点科技项目 (No.2 0 0 0 1 56)资