喷印柔性压力传感器试验研究

柔性压力传感器是智能机器人和生物医疗等典型应用领域中的关键部件。针对10～50 kPa中等压力下对柔性压力传感器的高灵敏度、良好压力分辨率和快速响应需求,提出在PDMS基底上直写喷印石墨烯纳米片(GNPs)/多壁碳纳米管(MWCNT)构建S型折线图案化敏感单元,结合封装层微结构阵列,制备中压高灵敏度、低检测限的柔性压力传感器。试验结果表明,在压力为0～15 kPa和15～40 kPa的条件下,该传感器灵敏度分别为0.114 kPa–1和1.41 kPa–1,响应/恢复速度快(约100 ms/50ms)。同时,其也可检测低至约3Pa的微小压力。同时,该传感器更是能对不同发声进行准确的区分识别,对不同的指压信号进行精确稳定反馈。可见,喷印制造柔性压力传感器将为语音识别、人工假肢、制备高性能电子皮肤和医疗康复器件等提供可能的优选方案

Optimum design of the well number for InGaAsP/InP SCH QW laser and its fabrication

【中文摘要】 根据对InGaAsP－InP分别限制量子阱激光器结构的注入效率的分析和利用X射线衍射对InGaAsP－InP20个周期的多量子阱结构异质界面的研究，设计、制备了4个阱的InGaAsP－InP分别限制量子阱激光器结构。利用质子轰击制得条形激光器。阈值电流为100mA，直流室温连续工作。单面输出外微分量子效率为36％。 【英文摘要】 Based on the analysis of injection efficiency for InGaAsP/InP SCH - QW laser and the research on X - ray diffraction kinetic simulation, a four - well InGaAsP - InP MQW laser structure is designed and fabricated. A stripe laser under CW operation with threshold as low as 100 mA is also obtained by means of proton implantation with single - side external differential quantum efficiency of 36%.福建省自然科学基金;国家自然科学基

The Choice of Well Number and Fabrication of InGaAsP Multiquantum-well Laser Diodes

【中文摘要】 针对目前多量子阱激光器结构设计中，忽略了载流子在每个阱内的注入不均匀性的问题，从油松方程和电流连续方程出发，提出每个阱单独考虑的计算方法，从而比较精确地计算出多量子阱激光器的净增益，给出多量子阱激光器的最佳阱数选择，根据设计结果，生长了ＩｎＧａＡｓＰ分别限制量子阱结构．利用质子轰击制得条形量子阱激光器，实现室温连续工作．阈值电流为６０ｍＡ，激射波长为１．５２μｍ，单面输出外微分量子效率为３６％． 【英文摘要】 The nonuniformity of carrier injected to each well was unreasonably neglected in conventional structure design of multiquantum well laser diode. This paper reports an optimization method by calculating separately the contribution of carrier injection of each well to the total net gain for the first time, based on Poisson's equation and continuity. A optimal choice of well number has been therefore given. According to the theoretic results, InGaAsP multiquantum well structure has been grown. The threshold ...国家自然科学基

台兰河绿洲灌区土地利用变化与水资源动态研究

基于2000年和2005年的遥感影像,利用RS,GIS及景观生态学方法,对台兰河绿洲灌区2000—2005年的土地利用进行监测,并分析了不同时期台兰河绿洲灌区水资源开发利用程度。对研究区土地利用与水资源动态变化关系进行了分析。结果表明,2000—2005年耕地面积和水域面积年均增加分别为3603.8hm2和151.4hm2;绿洲林地和草地大面积减少,减少量分别为2247.07hm2和14325.9hm2,相应地绿地面积减少了16572.97hm2;草地和林地等生态用地的减少是灌区耕地增加的主要来源,转移比例分别为13.97%和5.93%。地表来水量不断减少的情况下,灌区地下水开采量从1989年的5.91×106m3增加到2003年的1.39×107m3,灌溉面积和机井数量不断增大,地下水开采强度日益增加,地下水水位呈日益下降的趋势。农业用水所占比例过大,生态用水逐渐缩减

台兰河流域土地利用变化及其景观格局特征研究

在遥感和GIS技术支持下,获取了自1990年以来台兰河流域3期土地利用数据,在GIS空间分析模块下对台兰河流域土地利用及其景观格局特征进行了研究。结果表明:1990-2005年,土地利用变化表现出耕地和沙地明显增加,分别增加35 027.11 hm2和10 443.46 hm2,而草地和天然林地面积锐减,其中草地净减少59 965.95hm2,反映出流域有大面积拓荒的趋势。随着耕地面积的不断增大,引发农业用水和生态用水之间的矛盾,天然植被受到破环,生物多样性减少。老绿洲土壤盐渍化面积总体呈减小趋势,新绿洲及绿洲外围局部地区土壤盐渍化呈恶化趋势

近15年台兰河流域土地利用变化及其生态效应研究

利用1990、2000和2005年的TM影像数据,在GIS技术支持下,定量研究了近15年来台兰河流域的土地利用变化特征。结果表明:1990—2005年,台兰河流域耕地和沙地面积均明显增加,分别增加3.50万hm2和2.05万hm2,而草地和天然林地面积锐减,其中草地净减少6.00万hm2,反映出流域有大面积拓荒的趋势。选择研究区5组自然条件相同而土地利用方式不同的代表性样区进行对比研究,结果发现不同土地利用方式对土壤有机质含量及总盐的影响主要发生在0~25cm土层中,剖面中土壤有机质含量及总盐自上而下明显降低。人工甘草地和盐碱地的土壤总盐远高于其他土地利用类型,土壤表层(0~20cm)有机质含量在几种土地利用类型之间的比较是:经济林>耕地>人工甘草地>改良沙地>盐碱地。随耕种年限的增加耕地总盐含量降低,有机质含量增加

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies