Simultaneous Spectrophotometric Determination of Cadmium, Zinc and Copper with Kalman Filter

The compound 2-QADNm can form red complexes with caamium(II), zinc(II) and copper(II). The simultaneous determination of cadmium, zinc and copper with Kalman Filter is described in this paper, the proposed method was applied to a two-component system for determining cadmium and copper,and a three-component system for determining cadmium, zinc and copper.     

云南元江岔河铜矿床稀土元素地球化学特征及意义

岔河铜矿床为"火山沉积-变质"成因矿床,对岔河铜矿床进行矿相学分析以及稀土元素分析结果表明,稀土元素配分模式曲线为右倾型,轻稀土相对富集,重稀土相对亏损。δCe、δEu指示岔河铜矿床形成于相对氧化的环境。岔河铜矿床Cu部分来自地层,经变质作用富集成矿。     

一种三相三线与三相四线自适应电能表的设计

针对合成孔径雷达（SAR）清晰成像的特点,为保证雷达天线波束指向稳定,设计了某型机载雷达天线稳定平台。为了消除雷达天线稳定平台控制中存在的非线性及不确定性因素的影响,提出了一种应用于雷达天线稳定平台控制系统的模糊PID控制策略。稳定平台是依据陀螺仪所采集载机的角速度,运用反向运动补偿的原理进行工作。控制策略中,在传统PID控制的基础上引入模糊控制算法,根据跟踪误差信号动态改变PID控制器参数,改善稳定平台的控制效果,完成稳定平台控制器的优化设计。仿真结果表明,优化后的模糊PID控制算法与传统PID控制算法比较,在稳定平台转速控制方面受到的外部干扰影响更小,响应速度更快。因此,基于模糊PID控制算法的雷达天线稳定平台具有更高的稳定性能。     

Decrypting the Controlled Product Selectivity over Ag−Cu Bimetallic Surface Alloys for Electrochemical CO2 Reduction

Electrochemical CO₂ reduction reaction (ECO₂RR) with controlled product selectivity is realized on Ag−Cu bimetallic surface alloys, with high selectivity towards C2 hydrocarbons/alcohols (≈60 % faradaic efficiency, FE), C1 hydrocarbons/alcohols (≈41 % FE) and CO (≈74 % FE) achieved by tuning surface compositions and applied potentials. In situ spectral investigations and theoretical calculations reveal that surface-composition-dependent d-band center could tune *CO binding strengths, regulating the *CO subsequent reaction pathways and then the product selectivity. Further adjusting the applied potentials will alter the energy of participated electrons, which leads to controlled ECO₂RR selectivity towards desired products. A predominant region map, with an indicator proposed to evaluate the thermodynamic predominance of the *CO subsequent reactions, is then provided as a reliable theoretical guidance for the controllable ECO₂RR product selectivity over bimetallic alloys.     

Displacement sensor based on polarization mixture of orthogonal polarized He-Ne laser at 1.15μm

Displacement sensor based on the polarization mixture and the cavity tuning of the orthogonal polarized He-Ne laser 1.15μm is presented.The power tuning curves of He-Ne laser are irregular,and it is difficult to measure the change in cavity length.The distortion of the curves is caused by the higher relative excitation compared with the He-Ne laser at 633 nm.In view of its potential for the wider displacement measuring range,a new method of displacement sensing is developed.Experiments show that displacement measuring stability based on the method of the polarization mixture is better than that of the power tuning curves. The displacement sensor achieves the measuring range of 100 mm,resolution of 144 nm,and linearity of 7×10-6 .     

Isolation and Characterization of Four Phosphorus Cluster Anions P73–, P144–, P162– and P264– from the Nucleophilic Functionalization of White Phosphorus with 1,4‐Dilithio‐1,3‐butadienes

Studies on the aggregation degrees of negatively charged phosphides derived from the nucleophilic P₄ functionalization could help understand the pathway of phosphorus atoms degradation or aggregation. In this report, we have isolated and characterized four phosphorus cluster anions (P₇^3–, P₁₄^4–, P₁₆^2–, and P₂₆^4–) from the nucleophilic functionalization of P₄ with 1,4‐dilithio‐1,3‐butadienes. These phosphorus clusters could be rationalized as the P‐atom‐containing products besides the main phospholyl lithium. Their structural features and ³¹P NMR behaviors are discussed based on single crystal X‐ray diffraction analysis and ³¹P{¹H} COSY NMR analysis.     

径向浓浓淡旋流煤粉燃烧器直流二次风对气固流动的影响

本文综述了旋流燃烧器直流二次风对燃烧器区单相流动、烟气温度、煤粉燃尽及ＮＯｘ生成的影响,采用三维ＰＤＡ系统对不同直流二次风率下的气固速度分布、颗粒体积流量分布进行了测量,得出了其对气固流动的影响,分析了对燃烧器性能的影响。     

水、热、气、电四表合一数据采集系统的研究与应用

目前居民在用的水表、热表、气表、和电表四种表计虽然在抄表付费流程上相似,但由于分属不同部门管理,无法形成资源共享,既浪费工作量又给居民带来不便;文章论述了四表合一的技术构架,提出了从主站,通信信道,现场设备3个方面对现有系统进行升级的方法;首先,介绍了协议转换器的主要设计原理和用电信息采集设备—集中器的上下行通讯协议的改进方法,并且扩展协议转换器多种下行通讯方式以匹配市场上水表、热表、气表通讯方式多样化的现状,在用电信息采集系统平台上增加协议转换器及升级现有集中器程序,通过现场简单布线快速经济的实现四表合一数据采集;按此方案布局的四表合一采集试点,项目建设简洁、迅速,抄表运行稳定,一次性采集成功率在95%以上。     

Influence of mass-flow ratio of inner to outer secondary air on gas–particle flow near a swirl burner

The influence of mass-flow-rate ratio of inner to outer secondary air on gas–particle flow characteristics was determined in the near-burner region of a centrally fuel-rich swirl coal combustion burner. Velocity and particle volume flux profiles and normalized particle number concentrations were obtained. Peaks in tangential mean velocity and three-dimensional root-mean-square fluctuation velocities were found to decrease as the mass-flow-rate ratio increased. Moreover, the peaks in the mean axial velocities and particle volume flux near the wall increased, whereas those near the chamber axis decreased. Simultaneously, both recirculation zone and swirl number decreased as the mass-flow-rate ratio increased.     

曲面上离散点集的光滑插值

本文主要解决了如下问题：给定Ｒ３凸曲面上的任意个离散点｛Ｐｉ｝Ｎｉ＝１及其对应的函数值｛ｆｉ｝Ｎｉ＝１，要求构造曲面上的插值函数ｆ（ｘ），使得ｆ（Ｐｉ）＝ｆｉ，（ｉ＝１，２，…，Ｎ）．本文方法推广了球面上离散点集的Ｍｕｌｔｉｑｕａｄｒｉｃ插值方法，并且对分区域插值方法也给予了讨论．