Investigation of fusion reactions in palladium and titanium tritide using galvanostatic,coulometric, and hydrogen permeation techniques

We describe several electrochemical methods used to investigate the possibility of cold fusion phenomena in palladium and titanium tritide cathodes. We performed long-term (up to 77 days) electrolysis experiments with electrochemical cells of the University of Utah type at current densities as high as 1 A/cm², while monitoring neutron and tritium levels. With some cells, we pulsed the current to determine if neutron bursts would result. In another cell, we used titanium tritide as the cathode to determine if D-T reactions yielding neutrons would occur. In no instance were levels of neutrons or tritium significantly above background except in the titanium tritide cell where isotopic exchange, occcurring between the electrode and the electrolyte, resulted in significant tritium levels. We also combined x-ray photoelectron spectroscopy (XPS) and electrochemical hydrogen permeation experiments to determine the effectiveness of various Pd surface treatment procedures on the resultant electrochemical hydrogen absorption efficiency. Electroanalytical and thermal desorption/gas analysis techniques indicated the maximum loading of H in Pd was to a ratio of HPd=0.8.     

蒸发结晶操作中传热温差的选择

蒸发结晶是化工生产中常见的单元操作，在其加热过程中，较高的传热温差对于强化传热效率、提高设备能力极为有利。但是，传热温差过高会引起蒸发结晶操作的不稳定，甚至造成生产装置停车，使所追求的高效率适得其反。因此，必须合理选择传热温差，以保证生产装置在高效、稳定的状况下运行。     

液滴在热液相介质中上升汽化时的传热与传质

本文分析了液滴在不互溶的液相介质中上升汽化时的传热和传质,导出了数模,进行了数值求解,获知在泡滴与液相接触的汽液边界处温度下降和浓度升高,存在着溶液的过冷(或过饱和)边界层。实验结果与数模计算结果表明,该模型能够较好地预測液滴汽化的整体特性。     

氮磷钾高浓度烤烟专用肥

介绍硝酸铵－磷酸－铵－硫酸钾系高浓度烤烟专用复合肥的开发应用，三年的试验推广的实践证明，其肥效可与进口肥相媲美，配方合理，但价格比进口肥每吨低４００元左右。     

On-farm evaluation of leaf color chart for need-based nitrogen management in irrigated transplanted rice in northwestern India

Nitrogen use efficiency (NUE) in rice is low due to the inefficient management of fertilizer N by farmers. We evaluated a leaf color chart (LCC) as a simple tool for improving the time and rate of N fertilizer use in farmers’ fields for 4 years (2000–2003) in irrigated rice in northwestern India. Application of N fertilizer whenever leaf greenness was less than shade 4 on the LCC (the critical LCC value) produced rice grain yields on a par with blanket recommendation of applying 120 kg N ha⁻¹ in three equal splits in different years, but it resulted in an average saving of 26% fertilizer N across villages and seasons. In most situations, there was no significant advantage of applying 20 kg N ha⁻¹ as basal N at transplanting on grain yield and NUE of rice compared with no basal N. Use efficiencies of fertilizer N were higher when N was applied using LCC with a critical value of 4 than the recommended practice of applying 120 kg N ha⁻¹ in three equal split doses on all sites and in all years. The LCC with a critical value of 4 for real-time N management can be efficiently used to increase NUE in all types of inbred rice cultivars presently popular with the farmers of the Indian Punjab. The LCC is a cheap and easy-to-use tool that allows real-time N management by farmers on a large area leading to improved fertilizer N use efficiency, and reduced risks associated with fertilizer N application.     

Numerical study and optimization of the porous media VOC oxidizer with electric heating elements

Porous media VOC oxidizing reactor, consisting of coaxial tubes system with counter-flow heat exchange and embedded electric heater, is under investigation. Influence of heater configuration and power, gas flow rate and thermal isolation on maximum temperature in reactor and unburned VOC concentration is determined numerically. It is shown that axial configuration of the heater is more effective than the circular one in the case of high flow rates U_G  1 m/s or more. Minimum unburned VOC is reached if axial heater end is set at the level of the central tube edge.Practical porous media VOC oxidizer was simulated for the aim of the mathematical model verification. Comparison of simulated and measured non-steady temperature fields in the reactor during startup demonstrate reasonably good agreement (10–20%).     

雷达情报网生存能力评估方法的研究

提出了一种基于树结构的雷达情报网生存能力评估方法。该方法利用雷达情报网在指挥层次和信息流向呈现树型的特点,在功能单元的工作状态上采用“工作正常、完全失效”二态模式评估模型的基础上,运用雷达效能因子和各功能单元生存概率,给出了雷达情报网生存能力的一个量化描述。该方法具有直观和计算简单的特点。     

Doherty功率放大器研究与设计

在无线通信系统设计中,功率放大器设计是很重要的一部分,影响着整个系统的性能。效率和线性度则是功率放大器的两个重要的指标,也是设计功率放大器的重点。详细介绍了用来提高功率放大器效率的Doherty结构,并通过使用ADS2004仿真设计了一个符合指标的30 W Doherty功率放大器。     

歼击机碰撞引导截击效能的影响因素分析

歼击机引导阶段的完成情况直接影响截击效能.本文以雷达发现目标的概率作为截击效能的一个指标,推导了对歼击机碰撞引导时雷达发现目标概率的数学模型,并给出了具体的算例.在此基础上,分析了影响歼击机雷达发现目标概率的主要因素,得出了改善歼击机雷达及导航设备性能可以提高截击效能的结论.     

《计算机基础知识》教学谈讨

为了提高《计算机基础知识》的课堂教学质量，教师必须关注教学策略的设计和运用。要采取多种教学手段，为学生提供多样化的教学平台，激发他们的求知欲望，保持恒久的学习兴趣和动力；培养他们主动求知和渴望创造的学习品质，让他们获得成功的体验，提高学生的学习效能。