Crosstalk of HgCdTe LWIR n-on-p diode arrays

Crosstalk of HgCdTe long-wavelength infrared （LWIR） n-on-p diode arrays was measured using scanning laser microscopy. During the measurement, HgCdTe diode arrays with different diode pitches were frontside illuminated by a He-Ne laser at liquid nitrogen temperature and room temperature. The experimental results show that crosstalk between the nearest neighboring diodes decreases exponentially as the diode pitch increases, and the factors that affect the obtained crosstalk are presented and analyzed. Crosstalk out of the nominal diode area （optically sensitive area） is also measured and discussed.

Controlled Growth of Large-Area Aligned Single-Crystalline Organic Nanoribbon Arrays for Transistors and Light-Emitting Diodes Driving

Organic field-effect transistors(OFETs) based on organic micro-/nanocrystals have been widely reported with charge carrier mobility exceeding 1.0 cm^2V^(-1)s^(-1), demonstrating great potential for high-performance, low-cost organic electronic applications. However, fabrication of large-area organic micro-/nanocrystal arrays with consistent crystal growth direction has posed a significant technical challenge. Here, we describe a solution-processed dip-coating technique to grow large-area, aligned 9,10-bis(phenylethynyl) anthracene(BPEA) and 6,13-bis(triisopropylsilylethynyl) pentacene(TIPSPEN) single-crystalline nanoribbon arrays. The method is scalable to a 5 9 10 cm^2 wafer substrate, with around 60% of the wafer surface covered by aligned crystals. The quality of crystals can be easily controlled by tuning the dip-coating speed. Furthermore, OFETs based on well-aligned BPEA and TIPS-PEN single-crystalline nanoribbons were constructed.By optimizing channel lengths and using appropriate metallic electrodes, the BPEA and TIPS-PEN-based OFETs showed hole mobility exceeding 2.0 cm^2V^(-1)s^(-1)(average mobility 1.2 cm^2V^(-1)s^(-1)) and 3.0 cm^2V^(-1)s^(-1)(average mobility2.0 cm^2V^(-1)s^(-1)), respectively. They both have a high on/off ratio(I_(on)/I_(off))>10~9. The performance can well satisfy the requirements for light-emitting diodes driving.

Field Size Evaluation with a High Resolution 2D Diode Array for Variable-Aperture Collimators Used in Robotic Radiosurgery

Robotic radiosurgery/Radiotherapy is increasingly adopted in clinics, and quality assurance (QA) of CyberKnife’s variable-aperture IrisTM collimators requires sub-millimeter precision. Conventional film-based QA for the 12 IrisTM cone sizes (ranging from 5 to 60 mm) is both time consuming (120 minutes for all or 30 minutes for 3 cone sizes) and highly experience dependent. To improve the efficiency, a high-resolution 2D diode detector array, sampling every 2.5 mm, was evaluated for IrisTM aperture size QA. This study focused on a spatial frequency analysis, a dose profile reconstruction, and a sensitivity study to beam size variances. Dose profiles of the 12 cones scanned with a high-resolution diode in a water tank were utilized as the gold standard for comparison. Spatial Fourier transform of these profiles were analyzed to explore applicable sampling frequency. Next, the dose profiles were artificially sampled with a 2.5 mm gap, and then interpolated using a Python-based cubic B-spline. Finally, sensitivity of the diode array system to various field sizes was measured by changing source to detector distance. We found, utilizing the diodes system, QA time was reduced to less than 10 minutes. Spatial frequency of the dose profile showed little contribution beyond 0.2 mm-1, so a Nyquist sampling of 0.4 mm-1 is appropriate for dose verification, corresponding to a 2.5 mm gap. Dose profiles were reconstructed using Cubic B-spline with good agreements to nominal for cones 7.5 mm and larger. The measured IrisTM size using the SRS MapCheck had a standard error of ±0.12 mm. Primarily, the 2D Diode array with a spatial resolution 0.4 mm-1 is appropriate for dose verification for these cones above 7.5 mm, and its application would substantially improve IrisTM QA efficiency.

Design of Diode Type Un-Cooled Infrared Focal Plane Array Readout Circuit

The diode infrared focal plane array uses the silicon diodes as a sensitive device for infrared signal measurement. By the infrared radiation, the infrared focal plane can produces small voltage signals. For the traditional readout circuit structures are designed to process current signals, they cannot be applied to it. In this paper, a new readout circuit for the diode un-cooled infrared focal plane array is developed. The principle of detector array signal readout and small signal amplification is given in detail. The readout circuit is designed and simulated by using the Central Semiconductor Manufacturing Corporation （CSMC） 0.5 μm complementary metal-oxide-semiconductor transistor （CMOS） technology library. Cadence Spectre simulation results show that the scheme can be applied to the CMOS readout integrated circuit （ROIC） with a larger array, such as 320×240 size array.

Quantification of six bioactive compounds in Zhenqi Fuzheng preparation by high-performance liquid chromatography coupled with diode array detector and evaporative light scattering detector

A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation（ZFP）.The monitoring wavelengths were 254,275 and 328 nm.Under the optimum conditions,good separation was achieved,and the assay was fully validated in respect of precision,repeatability and accuracy.The proposed method was successfully applied to quantify the six ingredients in 31 batches of ZFP samples and evaluate the variation by hierarchical cluster analysis（HCA）,which demonstrated significant variations on the content of these compounds in the samples from different manufacturers with different preparation procedures.The developed HPLC method can be used as a valid analytical method to evaluate the intrinsic quality of this preparation.

Thermal analysis of GaN-based laser diode mini-array

Thermal characteristics of multiple laser stripes integrated into one chip is investigated theoretically in this paper. The temperature pattern of the laser diode mini-array packaged in a TO-can is analyzed and optimized to achieve a uniform temperature distribution among the laser stripes and along the cavity direction. The temperature among the laser stripes varies by more than 5 K if the stripes are equally arranged, and can be reduced to less than 0.4 K if proper arrangement is designed. For conventional submount structure, the temperature variation along the cavity direction is as high as 7 K, while for an optimized trapezoid submount structure, the temperature varies only within 0.5 K.

Comparison of Gamma Pass Rate between the Dose-to-Water and Dose-to-Medium Reporting Modes for Patient-Specific QA Using a Helical Diode Array Dosimeter with a Fixed Phantom Density

Introduction: To compare the measured dose distributions to calculated ones in dose-to-water (Dw) and dose-to-medium (Dm) reporting modes for simple plans and patient-specific intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) plans using ArcCHECK with a fixed phantom density. Methods: The recommended density value of 1.18 g/cm3 for Acuros XB and X-ray voxel Monte Carlo was assigned to ArcCHECK on CT images. A total of 45 simple plans, including a 1-field plan, a 3-field plan, a 4-field plan, a half-arc plan from 270° to 90°, and a full-arc plan, were assessed. Subsequently, the patient-specific 96 IMRT and VMAT plans were evaluated. Gamma analysis with a 3% normalized global dose error and a 3 mm distance-to-agreement criteria (γ3%G/3mm) was performed in the Dw and Dm. The change in γ3%G/3mm between Dw and Dm were statistically analyzed using JMPPro11 software. Results: The median values of γ3%G/3mm for all simple plans for Dw and Dm were 98.1% (range, 75.2% - 100%) and 95.5% (range, 23.7% - 100%), respectively (p 0.01). In the patient-specific IMRT and VMAT plans, the median values of γ3%G/3mm for Dw and Dm were 98.6% (range, 90.1% - 100%) and 90.5% (range, 38.5% - 97.2%), respectively (p 0.01). Conclusion: Our results showed that the calculated and measured dose distributions were in good agreement for Dw, but were not for Dm. From the viewpoint of the rationale of dosimetry, Dw shows better agreement with measured dose distribution when using the fixedphantom density recommended by the vendor.

用于SPAD阵列的高速主被动混和淬灭电路

单光子雪崩二极管(Single Photon Avalanche Diode,SPAD)具有响应速度快、抗干扰能力强等优点,具备优异的单光子检测能力,因而在激光雷达、量子通信应用、荧光光谱分析等弱光探测领域得到了广泛应用。在单光子探测成像领域中,为了获得更高的分辨率和更快的扫描探测速度,探测器正朝着大规模阵列化和高度集成化的方向发展,阵列应用要求淬灭电路较小的电路面积。基于盖革模式下SPAD的探测成像应用,建立了雪崩信号检测与淬灭的信号模型,并通过数学分析得到了混和淬灭电路中的最优检测电阻取值,在理论分析基础上对混合淬灭电路的结构和参数进行了设计与优化。根据建模分析结果,设计了一种主被动混合的高速淬灭电路结构,以较小的电路面积实现了雪崩信号快速检测与淬灭。基于TSMC 0.35μm CMOS工艺完成了电路版图的设计与流片。芯片测试结果表明,电路的淬灭时间约为2.9 ns,复位时间为1.75 ns。结合版图面积的占用情况,所设计的电路具有较高的“性价比”,可以满足SPAD阵列型读出电路的需求,具有快速雪崩淬灭和复位的特点。

OCC系统目标LED阵列解码算法研究

针对强日光环境下OCC(Optical Camera Communication)系统接收端解码困难的问题,提出了基于分段式线性灰度变换的Gradient-Harris解码算法。首先搭建一套OCC实验系统,接收端相机采集原始图像,利用标准相关系数匹配方法提取目标LED阵列区域。其次通过分段式线性灰度变换对目标LED阵列区域进行图像增强,利用Gradient-Harris解码算法进行目标LED阵列的形状提取和状态识别。实验结果表明,应用基于分段式线性灰度变换的Gradient-Harris解码算法,强日光环境下OCC实验系统的平均解码速率为128.08 bit/s,平均误码率为4.38×10^(-4),最大通信距离为55 m。

空间高功率激光二极管泵浦源阵列的相变热控系统

为了实现空间高功率激光二极管泵浦源阵列的快速散热,建立了空间高功率激光二极管泵浦源阵列相变热控系统,对热控系统的热界面材料(TIM)、紫铜热沉、相变材料、相变增强材料、主动加热回路和太空辐射板进行了研究与设计。首先,介绍了激光二极管泵浦源阵列的热特性与热控指标,从而提出热控设计思路,详细设计了热控系统,并在有无泡沫铜填空的条件下制定了两种热控方案。然后,用NX软件分析了两种不同的方案。分析结果显示:不填充泡沫铜方案的整个相变过程在800 s完成,LD上的温度最高达到59.98℃,相变材料上表面温度最高达到47.12℃;填充泡沫铜方案在200 s内完成相变过程,LD最高温度为38.35℃,并且LD在360 s后和相变温度点温度一致。填充泡沫铜方案可以满足10~40℃的温度指标要求。最后,根据填充泡沫铜方案设计加工了激光二极管泵浦源阵列热控系统,通过实验验证,该系统可以满足空间高功率激光二极管泵浦源阵列快速散热要求。

高效液相色谱法检测葡萄糖酸-δ-内酯

葡萄糖酸-δ-内酯常通过葡萄糖酸水溶液蒸发浓缩制备,所得产品常含有少量的葡萄糖酸和葡萄糖酸-γ-内酯。为了检测产品中葡萄糖酸-δ-内酯的质量分数,文中建立了可快速分离分析葡萄糖酸-δ-内酯、葡萄糖酸和葡萄糖酸-γ-内酯的高效液相色谱法,并优化了葡萄糖酸-δ-内酯的分析条件。以SPD-M20A二极管阵列检测器,采用Titank Hilic色谱柱分离葡萄糖酸-δ-内酯、葡萄糖酸和葡萄糖酸-γ-内酯,以0.01 mol/L乙腈-磷酸水溶液(体积比90∶10)为流动相进行等度洗脱,柱温为30℃,流速为1.0 mL/min,检测波长为205 nm,进样量为20μL。结果表明,葡萄糖酸-δ-内酯在7 min内可实现较好的分离;在0.5—2.5 mg/mL内具有良好的线性关系(r>0.999),检出限为0.002 mg/mL,定量限为0.5 mg/mL,3个水平的平均加标回收率为98.8%—99.9%,相对标准偏差0.1%—0.4%(n=5)。此方法分析时间短、灵敏度高、分离效果好,可用于葡萄糖酸-δ-内酯、葡萄糖酸和葡萄糖酸-γ-内酯的同时检测。

基于HPLC⁃DAD指纹图谱结合化学模式识别的红糖产地溯源方法

红糖作为一种功能食品,近年来需求量不断增长,然而市场上红糖的品质却良莠不齐,且缺乏科学的鉴别和评估方法来确保红糖的品质。该研究以我国5个红糖主产地(广西、广东、云南、贵州和香港地区)的55批红糖作为研究对象,通过构建高效液相色谱⁃二极管阵列检测器(high⁃performance liquid chromatography⁃diode array detector,HPLC⁃DAD)指纹图谱并结合共有模式法、相似度评价法和化学计量学法,建立一种能够准确追溯红糖产地的方法。研究发现,不同产地的红糖既有特有的HPLC⁃DAD指纹图谱也有共有的HPLC⁃DAD指纹图谱,特有的HPLC⁃DAD指纹图谱显示产地特有峰的保留时间具有明显的地域特性,与产地区分密切相关。产地共有指纹图谱共标定出9个共有峰,指纹图谱的相似度为0.473~0.915,表明虽然存在共有峰但共有峰峰面积存在明显差异(例如广东、广西、云南、贵州和香港地区的S2号共有峰的平均相对峰面积分别为47.592%、26.873%、814.853%、8.683%和3.111%)。共有峰峰面积的聚类热图显示不同地区的样品存在明显差异。此外,共有峰峰面积的主成分分析发现前3个主成分对产地区分的贡献率分别为59.9%、17.1%和11.6%,累计贡献率为88.6%,可以作为鉴别红糖产地的特征性指标。

高效液相色谱-二极管阵列检测器法测定洋葱中的硫化丙烯和烯丙基硫醚

该研究建立了高效液相色谱-二极管阵列检测器法测定洋葱中的硫化丙烯和烯丙基硫醚方法。样品中加入丁硫醇后经乙腈提取,用无水硫酸钠吸收多余的水分后离心,用Thermo Hypersil GOLD液相色谱柱(150 mm×4.6 mm,5μm),以乙腈和水为流动相,流速为1.0 mL/min,柱温为35℃,进样量为10μL,高效液相色谱-二极管阵列检测器检测范围为190~400 nm,检测波长为200 nm。硫化丙烯和烯丙基硫醚在1~100μg/mL质量浓度内线性相关系数R为0.99997~0.99998,方法检出限为0.5 mg/kg,定量限为1.5 mg/kg,5、10、15μg/mL 3个浓度加标水平的回收率为96%~103%,相对标准偏差分别为0.28%~0.49%。该方法前处理简单,科学性、准确性、重现性、精密性好,适用于洋葱中硫化丙烯和烯丙基硫醚分析检测。

反相液相色谱-二极管阵列法测定消毒产品中苯扎氯铵3种同系物的含量

目前标准方法检测苯扎氯铵时仅用了一个平均相对分子质量洁尔灭来表示两种或几种混合物,无法区别苯扎氯铵的几种同系物,为了测定苯扎氯铵同系物的含量,进行了题示研究。取消毒产品1.0000 g,用水稀释并定容至10 mL,超声提取5 min,静置,过0.45μm聚砜醚水相滤膜,滤液中苯扎氯铵3种同系物十二烷基二甲基苄基氯化铵、十四烷基二甲基苄基氯化铵、十六烷基二甲基苄基氯化铵在Agilent XDB-C_(18)色谱柱(250 mm×4.6 mm,5μm)上分离,以体积比70:30的乙腈-含0.1%(体积分数)三乙胺的0.5 g·L^(-1)乙酸铵缓冲溶液(pH 5.0)为流动相进行等度洗脱,采用二极管阵列检测器在262 nm处检测。结果表明,扫尾剂三乙胺的体积分数从1%降低到0.1%,避免了扫尾剂三乙胺对色谱柱的可能损害,解决了出现鬼峰的问题。苯扎氯铵3种同系物的质量浓度在10~500 mg·L^(-1)内与对应的峰面积呈线性关系,检出限(3S/N)分别为1.1,1.2,1.5 mg·L^(-1)。按照标准加入法进行回收试验,回收率为98.8%~105%,测定值的相对标准偏差(n=8)均小于2.0%。方法用于实际消毒产品的分析,检出量为0.027%~44.60%,从微量到常量均有涉及。

HPLC-DAD测定饲用酸化剂苯甲酸中7种邻苯二甲酸类杂质

为了建立高效液相色谱法测定饲用酸化剂苯甲酸中邻苯二甲酸、2-羟基苯甲酸、3-羟基苯甲酸、4-羟基苯甲酸、2-甲基苯甲酸、3-甲基苯甲酸和4-甲基苯甲酸共7种邻苯二甲酸类杂质的方法。本试验将酸化剂样品溶于甲醇和初始流动相的混合溶液中,采用Agilent ZORBAX SB-C18色谱柱(4.6 mm×250 mm,5.0μm)分离7种邻苯二甲酸类杂质,以水-乙腈-甲基磺酸(85-15-0.1)和乙腈为流动相进行梯度洗脱,流速为1.2 mL/min,采用二极管阵列检测器(DAD),采集波长范围为210~400 nm,记录扫描光谱图和235 nm波长处的色谱图。用外标法定量邻苯二甲酸类杂质的含量。结果显示,7种邻苯二甲酸类杂质的浓度在0.10~40.00μg/mL范围内的线性良好,平均加标回收率在98.5%~102.7%范围内,相对标准偏差(RSD,n=5)介于0.3%~1.5%,检测限和定量限均为4 mg/kg。本试验建立的酸化剂苯甲酸中7种邻苯二甲酸类杂质的高效液相色谱-二极管阵列检测器(HPLC-DAD)检测方法快速且准确,可用于苯甲酸中7种邻苯二甲酸类杂质的定性和定量检测。

基于超像素的硅基有机发光二极管微显示器

基于超像素技术,针对彩色硅基OLED(Organic Light Emitting Diode)微显示器,提出一种数字驱动策略,通过复用相邻像素信息,使单像素用于多个相邻像素成像,大幅提高显示分辨率.设计了一种数字驱动彩色OLEDoS(Organic Light Emitting Diode on Silicon)微显示器驱动电路,在120 Hz帧频的条件下,可实现256级灰度和4K显示分辨率,且电路面积和每秒数据传输量仅为传统驱动方式的50%.经测试验证,该驱动电路可实现的OLED像素平均电流范围为13.1 pA~3.74 nA,可满足微显示器近眼显示需求.

纺织染整助剂中5种异噻唑啉酮类化合物的高效液相色谱法测定

建立了纺织染整助剂产品中5种异噻唑啉酮类化合物的高效液相色谱-二极管阵列检测器(HPLC-DAD)检测方法。该方法采用甲醇作为溶剂,经超声波提取纺织染整助剂产品中的目标分析物,再进行HPLC-DAD测定。结果表明,5种异噻唑啉酮类化合物在0.5~10.0 mg/L范围内线性相关系数大于0.999。方法检出限为7.5 mg/kg,定量限为25.0 mg/kg,加标回收率为87.06%~112.79%,相对标准偏差为1.07%~8.14%。该方法灵敏度高、重现性好、操作简便,可以满足纺织染整助剂中异噻唑啉酮类化合物的检测要求。

利用UPLC-DAD-HRMS分析低温压榨鲜青花椒油贮藏期间的色素变化

旨在为低温压榨鲜青花椒油的工业生产、贮藏和质量控制提供借鉴,利用超高效液相色谱-二极管阵列检测器-高分辨质谱(UPLC-DAD-HRMS)技术对低温压榨鲜青花椒油中色素进行测定,并研究贮藏过程中光、氧、温度对低温压榨鲜青花椒油的色素含量和色泽L^(*)、a^(*)、b^(*)的影响。结果表明:从低温压榨鲜青花椒油中鉴定出32种叶绿素和10种类胡萝卜素;叶绿素中主要含有叶绿素a、C13^(2)-羟基-叶绿素a、叶绿素b和脱镁叶绿素a;类胡萝卜素中主要含有叶黄素和β-胡萝卜素;叶绿素总量为9.44mg/kg,类胡萝卜素总量为4.95mg/kg。贮藏过程中影响低温压榨鲜青花椒油中色素降解最主要的因素是光,其次是温度,氧气几乎没有影响。另外,a^(*)可以作为衡量低温压榨鲜青花椒油色素含量及色泽控制的指标。

高效液相色谱-二极管阵列检测器测定独一味胶囊中木犀草素含量的研究

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