1978～2008年中国湿地类型变化

分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978～2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978～2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978～1990年)降为831km2/a(2000～2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978～1990年)几乎全部(98%)转换为非湿地;在1990～2000年间减少的自然湿地约有86%转化为非湿地,而在2000～2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动

一种用于检测痕量重金属的合金电极电化学传感器

本发明涉及电化学传感器领域，具体的说是一种用于痕量重金属快速检测的合金电极电化学传感器。具体为包括合金工作电极、参比电极和辅助电极，工作电极、参比电极和辅助电极分别通过导线连接于控制电位仪；所述工作电极由锡铋合金制作而成。检测方法是将三电极插入待测样品中，采用溶出伏安法对待测样品中的重金属离子浓度进行检测。本发明工艺简单，成本低廉、选择性和灵敏度高，稳定性好，可广泛应用于淡水、海水、食品、体液中重金属离子的现场快速检测和日常监测

Alloy electrode electrochemical sensor for detecting trace heavy metals

本发明涉及电化学传感器领域，具体的说是一种用于痕量重金属快速检测的合金电极电化学传感器。具体为包括合金工作电极、参比电极和辅助电极，工作电极、参比电极和辅助电极分别通过导线连接于控制电位仪；所述工作电极由锡铋合金制作而成。检测方法是将三电极插入待测样品中，采用溶出伏安法对待测样品中的重金属离子浓度进行检测。本发明工艺简单，成本低廉、选择性和灵敏度高，稳定性好，可广泛应用于淡水、海水、食品、体液中重金属离子的现场快速检测和日常监测

Migration Characteristic of Spherical Nanoparticles from Liquid to Vapor Phase during Refrigerant/Nanolubricant Mixture Boiling

为了评估纳米制冷剂的沸腾传热效果以及球形纳米颗粒在制冷系统中的循环能力,采用称重法实验研究了纳米制冷剂沸腾中气/液相间球形纳米颗粒的迁移特性,重点考察球形纳米颗粒种类和粒径、制冷剂种类、润滑油浓度、热流密度和初始液位高度对球形纳米颗粒迁移特性的影响.结果表明:球形纳米颗粒迁移率随球形纳米颗粒密度或粒径的减小而增大;制冷剂的动力学黏度越小、密度越大,其在完全蒸发时的球形纳米颗粒的迁移率越大;球形纳米颗粒的迁移率随润滑油浓度的增大而减小,随热流密度的增大而减小,随初始液位高度的增加而增大

On-line Monitoring of Dissolved Oxygen in Water by a Fiber-optic Chemical Sensor Based on Fluorescence Quenching

利用氧分子对芘丁酸的荧光具有猝灭作用的特性 ,构造出基于荧光猝灭原理的光纤氧化学传感器。就用于水中溶解氧在线监测的光纤光谱仪的搭建、传感探头的设计及传感膜的制作进行了探索 ,并对传感器的响应性能进行了考察。结果表明以三醋酸纤维素为固相支持剂、邻苯二甲酸二辛酯为增塑稳定剂、芘丁酸为分析物识别器制备的传感膜对溶解氧的响应具有良好的可逆性 ,稳定性 ,较快的响应时间和较长的使用寿命。与标准法相对照 ,用本仪器系统测定了不同盐度的人工海水中的溶解氧浓度 ,两种方法在不同浓度水平下的溶解氧测定值均无显著性差异。本法的日内和日间RSD在 2 4 %～ 6 1%之间A novel circulatory system for on\|line monitoring of dissolved oxygen that makes use of a fiber\|optic chemical sensor is presented.An oxygen sensitive optode was combined with a membrane onto which was immobilized pyrenebutyric acid as a fluoroprobe,the membrane was composed of cellulose triacetate as a polymer and di\|(2\|ethyl hexyl)\| o \|phthalate as a plasticizer.The dissolved oxygen in water was determined via quenching of the fluorescence of pyrenebutyric acid.The optode shows a satisfactory linear response for the dissolved oxygen in water( r =0 995?6, n =6).The relative standard deviations were 2 4%～6 1%. The detection limit was 0 03?μg/mL( S/N =3).The exposure time and recovery time of the optode membrane are 5s and 25s respectively.The reversibility of the fluorescence signal was evaluated by alternate measurements in air saturated water and nitrogen\|purged water.The relative standard deviation( n =6)were found to be 0 7%.The fluorescence intensity of the membrane in contact with flowing water was recorded over a period of 96?h.From fluorescence intensity values taken every 4?h( n =24)a RSD of 8% was obtained.After 3 month,the fluorescence signal of the membrane had decreased by 14%.The decrease may be due to washing out of fluoroprobe,but this was not an obstacle to its further use;the quantitative information( F 0/ F )did not change significantly,where F 0 and F are the fluorescence intensities in the absence and in the presence of oxygen,respectively.The sensor has good reproducibility and long\|term stability.The interference was investigated and the selectivity of method in seawater was affirmed by a conventional method.国家“九五”科技攻关 !(96 A2 3 0 2 0 8);; 国家“八六三”高技术计划海洋领域 !(818 Q 0 9)资助项

Study on the Fiber Optic Chemical Sensors and Biosensors Applied to Monitoring for Environmental Contaminants in Seawater

本文通过光纤溶解氧、 p H、湿度等化学传感探头及发光菌水质毒性监测生物传感探头的研制 ,开发出了一类能用于环境监测的新型传感器。本文的创新之处在于传感探头的设计与包装 ,以及数种可逆性、选择性、稳定性、使用寿命、响应时间、灵敏度等响应特性具佳的化学及生物传感膜的配方和制作技术。利用这些技术 ,通过对光纤探头的设计与包装 ,可以实现在现场及实验室模拟条件下对样品的选择性检测。研制的传感器能广泛应用于海洋污染调查、内河水质评价、水产养殖、工矿企业水气排污自检等诸多方面。Some novel circulatory system for on-line monitoring of dissolved oxygen, pH, humidity and pollutants that make use of fiber-optic chemical sensors and biosensors are presented Some useful approach have been employing chemical and bioluminescent reporter systems that involve whole molecular probes and bioluminescent microbes which provide rapid and visible responses to dissolved oxygen, pH, humidity and the presence of harmful chemicals, including heavy metal ions and petrochemical industry waters Coupling such chemical and biological detection systems with fiber optic chemical sensors and biosensors for environmental monitoring combines rapid response times, low costs and improved reproducibility国家 8 6 3计划海洋领域 ( 818-0 8-16、 818-0 9-0 5、 818-Q-0 9、 818- 0 9-0 7)资助项

Study on the Fiber Optic Chemical Sensors and Biosensors Applied to Monitoring for Environmental Contaminants in Seawater

通过光纤溶解氧、p H、湿度等化学传感探头及发光菌水质毒性监测生物传感探头的研制 ,开发出了一类能用于环境监测的新型传感器 .其创新之处在于传感探头的设计与包装 ,以及数种可逆性、选择性、稳定性、使用寿命、响应时间、灵敏度等响应特性具佳的化学及生物传感膜的配方和制作技术 .利用这些技术 ,通过对光纤探头的设计与包装 ,可以实现在现场及实验室模拟条件下对样品的选择性检测 .研制的传感器能广泛应用于海洋污染调查、内河水质评价、水产养殖、工矿企业水气排污自检等诸多方面Rapid and continuous detection of environmental contaminants in effluents and waterways is important for protecting natural environments and public health, and for managing waster treatment systems. Some novel circulatory system for on line monitoring of dissolved oxygen, pH, humidity and pollutants that make use of fiber optic chemical sensors and biosensors are presented. Some useful approach have been employing chemical and bioluminescent reporter systems that involve whole molecular probes and bioluminescent microbes which provide rapid and visible responses to dissolved oxygen, pH, humidity and the presence of harmful chemicals, including heavy metal ions and petrochemical industry waters. Coupling such chemical and biological detection systems with fiber optic chemical sensors and biosensors for environmental monitoring combines rapid response times, low costs and improved reproducibility.“九五”国家重点科技攻关计划!(96 - A2 3- 0 2 - 0 8);; 国家 86 3计划海洋领域!(818- 0 8- 16、818- 0 9- 0 5、818- Q- 0 9、818-

含油金刚石纳米制冷剂的核态池沸腾换热特性

研究了含油金刚石纳米制冷剂（即由制冷剂R113、润滑油VG68和金刚石纳米颗粒组成的纳米流体）的核态池沸腾换热特性,分析了金刚石纳米颗粒对含油制冷剂核态池沸腾换热的影响.实验中饱和压力为101.3 kPa;热流密度为10～80 kW/m2;纳米油（纳米颗粒和润滑油的混合物）的质量分数为0～5%;在纳米油中金刚石纳米颗粒的质量分数为0～15%.实验结果表明：金刚石纳米颗粒增强了含油制冷剂的池沸腾换热,在测试工况下换热系数最大可增加63.4%,并且增加幅度随纳米油中纳米颗粒质量分数的增加而增加,随纳米油质量分数的降低而增加.开发了含油纳米制冷剂池沸腾换热关联式,关联式预测值与94%的实验数据偏差在±20%以内

Fabrication of Relative Humidity Optical Fiber Sensor Based on Nafion Crystal Violet Sensing Film

通过研究基于荧光和可见光吸收的两种湿度传感方法,从数种湿度分子探针中优选出结晶紫为分子识别器,包埋于Nafion溶胶中,制备成基于可见光吸收原理的光纤化学湿度传感膜。该传感膜与电荷耦合二极管阵列检测器等构成的光纤湿度传感器,于640nm波长处对30%~100%范围内的相对湿度(rela-tivehumidity,RH)具有较快的响应时间(<2min)、较高的灵敏度(≤5%RH)、选择性和良好的可逆性(RSD≤2.6%)。With two kinds of sensing methods for relative humidity based on fluorescence and visible Absorption respectively, crystal (violet) was opted as the molecule probe for humidity. The optical chemical sensing film for humidity was prepared when crystal violet was embedded in the Nafion gel. The relative humidity sensor was fabricated after the sensing film had been coupled with other components, such as optical fiber and detector, which possessed short response time (<2 min), high sensitivity (≤5% RH), wide dynamic range (30%-100%) and good reversibility (RSD≤2.6%) for relative humidity at 640 nm wavelength.国家高科技“863”计划(818-09-07)资助项

Nucleate Pool Boiling Heat Transfer Characteristics of Refrigerant/Oil Mixture with Carbon Nanotubes

通过实验研究了基于碳纳米管（CNTs）的含油纳米制冷剂（即由制冷剂R113、润滑油VG68和碳纳米管组成的纳米流体）的核态池沸腾换热特性，分析了碳纳米管对含油制冷剂核态池沸腾换热的影响。实验中采用了外径为15~80nm、长度为1.5~10&mu;m的四种碳纳米管。实验的饱和压力为101.3 kPa；热流密度为10~80 kW/m~2；纳米油（碳纳米管和润滑油的混合物）的质量分数为0~5%；在纳米油中碳纳米管的质量分数为0~30%。实验结果表明：碳纳米管增强了含油制冷剂的池沸腾换热，在测试工况下换热系数最大可增加61%。当纳米油中碳纳米管浓度为20%不变，纳米油浓度由1%提高到5%时，不同尺寸的碳纳米管对换热系数的增加幅度由27%~59%降低至23%~55%；当纳米油的浓度为1%不变，纳米油中碳纳米管浓度由20%提高到30%时，不同尺寸的碳纳米管对换热系数的增加幅度由27%~59%升高到33%~61%。通过实验获得了基于碳纳米管的含油纳米制冷剂池沸腾换热关联式，关联式的预测值与96%的实验数据偏差在&plusmn;10%以内。</p