基于GF-1影像的巢湖浊度遥感监测及时空变化研究

浊度监测可以为湖泊水质的污染防控和预警提供科学依据.为了提高湖泊浊度的动态监测能力,将卫星遥感监测和浮标检测站监测相结合,对2019年巢湖浊度的时空变化进行分析.浮标检测站监测通过高频次连续的实测浊度数据的统计分析,研究巢湖浊度时空变化特征;遥感监测通过构建最优波段组合模型对浊度进行定量反演.研究结果表明:(1)巢湖整...     

基于S3C44B0与S1D13506的多功能显示终端的设计与实现

设计实现了一种基于S3C44B0微处理器和S1D13506视频控制器的多功能显示终端,具有成本低、配置性高、应用范围广等特点.介绍了该终端的整体结构, 详细描述了各个组成模块的设计实现方法及涉及的相关技术,并给出了验证结果.     

基于高分一号遥感卫星的渤海湾悬浮泥沙时空分布反演

悬浮泥沙是评价II类水体水质的重要参数之一,近海岸水域悬浮泥沙对重金属、营养盐等具有一定的吸附作用,悬浮泥沙的分布特征在一定程度上反映着污染物的迁移和循环,因此研究悬浮泥沙对渤海湾建设和环境保护具有重要意义。为探究渤海湾水域悬浮泥沙浓度和分布的变化特征,利用高分一号多光谱卫星影像,通过采用波段组合的方式对悬浮泥沙含量指数反演提取,反演得到2019年9个月的渤海湾悬浮泥沙指数,分析发现渤海湾悬浮泥沙含量在冬季受季风影响较高,春季和夏季的时候渤海湾高浓度悬浮泥沙向近岸收缩,秋季悬浮泥沙分布格局有正在向冬季过渡的趋势,本文研究可为渤海湾的生态环境保护和工业开发提供重要的科学依据和参考价值。     

卡氏肺孢子菌肺炎鼠肺模式识别受体Dectin-1、TLR-2和TLR-4的表达变化

目的：研究卡氏肺孢子菌（Pnemnocystis carinii,Pc）肺炎鼠肺Dectin-1、TLR-2和TLR-4的表达,探讨模式识别受体表达改变与PCP疾病发生的相互关系。方法实验分4组：正常对照组、Pc刺激组、PCP模型组以及PCP模型恢复组。地塞米松磷酸钠免疫抑制方法建立PCP动物模型,改良四胺银（GMS）染色检测Pc包囊;肺组织切片HE染色观察肺组织病理变化;实时荧光定量和Western—blot检测Dectin-1、TLR-2和TLR-4的mRNA以及蛋白的表达。结果：Pc刺激组的Decdn-1、TLR-2以及TLR-4的mRNA以及蛋白的表达明显高于正常对照组（P〈0．05）;Pc刺激组和PCP恢复组Dectin-1的mRNA以及蛋白显著高于PCP组（P〈0．05）,而肺部Pc载荷量显著低于PCP组（P〈0．05）。结论地塞米松抑制了PCP鼠肺Dectin-1、TLR-2和TLR-4受体的表达,这可能与PCP疾病的发生和发展有关。     

Synthesis and photophysical properties of semiconductor molecules D1-A-D2-A-D1-type structure based on derivatives of quinoxaline and dithienosilole for organics solar cells

A novel small molecule with D1-A-D2-A-D1 structure denoted as DTS(QxHT₂)₂ based on quinoxaline acceptor and dithienosilone donor units was synthesized and its optical and electrochemical properties were investigated. The thin film of DTS(QxHT₂)₂ showed a broad absorption profile covering the solar spectrum from 350 nm to 780 nm with an optical bandgap of 1.63 eV. The energy levels estimated from the cyclic voltammetry indicate that this small molecule is suitable as donor along with PC₇₁BM as acceptor for the fabrication solution processed bulk heterojunction solar cells for efficient exciton dissociation and high open circuit voltage. The organic solar cells based on optimized DTS(QxHT2)2:PC₇₁BM active layers processed with chloroform and DIO/CF showed overall power conversion efficiency of 3.16% and 6.30%, respectively. The higher power conversion efficiency of the solar cell based on the DIO/CF processed active layer is attributed to enhanced short circuit photocurrent and fill factor may be related to better phase separation between donor and acceptor in the active layer and more balanced charge transport, induced by the solvent additive. The power conversion efficiency of the organic solar cell was further improved up to 7.81% based on active layer processed with solvent additive, using CuSCN as hole transport layer instead of PEDOT:PSS and mainly attributed to increased fill factor and open circuit voltage due the formation of better Ohmic contact between the active layer and the CuSCN layer.     

基于AT89C51和DS18820的最简温度测量系统的设计

设计了以美国DALLAS半导体公司的单总线温度传感器DS18820为核心，以ATMEL公司的AT89C51为控制器的最简温度测量系统。介绍了系统的结构、硬件和软件，并给出了AT89C51与DS18820通讯的部分汇编语言代码。与传统装置比，具有结构简单、抗干扰能力强、测量精度高、适用范围广等特点。     

Anisotropic Properties of Quasi-1D In4Se3: Mechanical Exfoliation,Electronic Transport,and Polarization-Dependent Photoresponse

Theoretical and experimental investigations of various exfoliated samples taken from layered In₄Se₃ crystals are performed. In spite of the ionic character of interlayer interactions in In₄Se₃ and hence much higher calculated cleavage energies compared to graphite, it is possible to produce few-nanometer-thick flakes of In₄Se₃ by mechanical exfoliation of its bulk crystals. The In₄Se₃ flakes exfoliated on Si/SiO₂ have anisotropic electronic properties and exhibit field-effect electron mobilities of about 50 cm² V⁻¹ s⁻¹ at room temperature, which are comparable with other popular transition metal chalcogenide (TMC) electronic materials, such as MoS₂ and TiS₃. In₄Se₃ devices exhibit a visible range photoresponse on a timescale of less than 30 ms. The photoresponse depends on the polarization of the excitation light consistent with symmetry-dependent band structure calculations for the most expected ac cleavage plane. These results demonstrate that mechanical exfoliation of layered ionic In₄Se₃ crystals is possible, while the fast anisotropic photoresponse makes In₄Se₃ a competitive electronic material, in the TMC family, for emerging optoelectronic device applications.     

Reversible Formation of g‐C3N4 3D Hydrogels through Ionic Liquid Activation: Gelation Behavior and Room‐Temperature Gas‐Sensing Properties

Many unique properties arise when the 3D stacking of layered materials is disrupted, originating nanostructures. Stabilization, and further reorganization of these individual layers into complex 3D structures, can be essential to allow these properties to persist in macroscopic systems. It is demonstrated that a simple hydrothermal process, assisted by ionic liquids (ILs), can convert bulk g‐C₃N₄ into a stable hydrogel. The gelation occurs through delamination of the layered structure, driven by particular interactions between the IL and the carbon nitride sheets, forming an amphiphilic foam‐like network. This study employs spectroscopic and computational tools to unravel the gelation mechanism, and provides a rational approach toward the stabilization of 2D materials in hydrogels. The solution‐processable hydrogels can also be used as building blocks of complex devices. Chemiresistive gas sensors employing g‐C₃N₄ 3D hydrogels exhibit superior response at room temperature, enabling effective gas sensing under low power conditions.     

mTOR/p-4EBn,p-p70S6k信号通路对绒癌细胞株JEG-3的作用

目的:运用雷帕霉素对mTOR的特异性抑制作用,探讨mTOR信号通路对人绒癌细胞株JEG-3的作用的分子机制.方法:运用RT-PCR检测雷帕霉素对其靶点mTOR的mRNA表达鞋的影响;用western-blot检测雷帕霉素处理后mTOR及调控的下游蛋白P-4EBPI和p-P70S6K的蛋白表达量的变化.结果:绒癌细胞JE...     

Comments on `Stability analysis, design, and simulation of aclosed-loop converter-controlled DC drive' by P.B. Anjaneyulu, etal

Applying Popov's stability criterion to the correct transfer function for the system studied in the work P.B. Anjaneyulu et al. (see ibid., vol.IE-31, no.2, p.175-80, (1984)), suitable conditions for stability are derived. From these conditions, the stability region obtained is larger than that given in the mentioned work. These results can be verified by using Lyapunov's second method     

Comment, with reply, on `Analysis of a static power converter underunbalance: a novel approach' by P. N. Enjeti and P.D. Ziogas

The commenter argues that the expressions obtained in the above-named work (see ibid., vol.37, no.1, pp.91-93, Feb. 1990) by P.N. Enjeti and P. D. Ziogas for the harmonics of the output voltage are in error. Certain modifications of the formulas presented by Enjeti and Ziogas are suggested. An authors' reply is presented     

Solution of X?=A1X+XA2+D, X(0)=C and receding horizon problem

A new numerical solution for X of the general matrix differential equation X?=A1X+XA2+D, X(0)=C is considered. The new algorithm removes any restrictions on the stability requirements of A1 and A2. The proposed method provides memory as well as time saving compared to other techniques. An efficient way to solve the receding horizon control problem is established.     

Efficient Reverse Converters for 4-Moduli Sets {2^{2n-1}-1, 2^{n}, 2^{n}+1, 2^{n}-1} and {2^{2n-1}, 2^{2n-1}-1, 2^{n}+1, 2^{n}-1} Based on CRTs Algorithm

Speed and complexity of a reverse converter are two important factors that affect the performance of a residue number system. In this paper, two efficient reverse converters are proposed for the 4-moduli sets {2 \(^{2n-1}-1\) , 2 \(^{n}\) , 2 \(^{n}+1\) , 2 \(^{n}-1\) } and {2 \(^{2n-1}\) , 2 \(^{2n-1}-1\) , 2 \(^{n}+1\) , 2 \(^{n}-1\) } with 5 \(n\) -bit and 6 \(n\) -bit dynamic range, respectively. The proposed reverse converter for moduli set {2 \(^{2n-1}-1\) , 2 \(^{n}\) , 2 \(^{n}+1\) , 2 \(^{n}-1\) } has been designed based on CRT and New CRT-I algorithms and in two-level structure. Also, an efficient reverse converter for moduli set {2 \(^{2n-1}\) , 2 \(^{2n-1}-1\) , 2 \(^{n}+1\) , 2 \(^{n}-1\) } has been designed by applying New CRT-I algorithm. The proposed reverse converters are based on adders and hence can be simply implemented by VLSI circuit technology. The proposed reverse converters offer less delay and hardware cost when compared with the recently introduced reverse converters for the moduli sets {2 \(^{n}+1\) , 2 \(^{n}-1\) ,2 \(^{n}\) , 2 \(^{2n+1}-1\) } and {2 \(^{n}+1\) , 2 \(^{n}-1\) , 2 \(^{2n}\) , 2 \(^{2n+1}-1\) }.     

基于三维虚拟现实的便携式3C产品外观仿真设计与实现

为了增强便携式3C产品企业的竞争力,需研究一种有效的外观设计技术。传统方法通过设置产品各组件的外观属性对便携式3C产品外观进行设计,设计结果不直观,不能有效展现所设计便携式3C产品的外观。为此,设计一种基于三维虚拟现实的便携式3C产品外观仿真设计系统,分析系统的总体结构,通过输入模块对用户发出的命令进行接收和检测,输入模块将接收到的命令发送至图像处理模块,通过将软件代码植入芯片中实现便携式3C产品外观的仿真设计,将设计结果发送至NOR FLASH存储电路暂存,将最终设计完成的结果传输至VGA显示模块进行显示。软件设计中,采用三维虚拟现实技术实现便携式3C产品外观设计。实验结果表明,所设计系统外观设计效果较佳,且效率很高。