A flip-flop sensor array with on-spot A/D conversion

A two-dimensional optical flip-flop sensor array, consisting of an 8×8 matrix of flip-flop sensors integrated in one chip together with sense amplifiers and access selection circuitry, is discussed. A flip-flop sensor contains two phototransistors, one of which is covered over the aluminum while the other is exposed to light. Each flip-flop senses the light intensity and converts it to a series of ones and zeros. It is operated by turning the supply current on and off with a high frequency. During the absence of light the flip-flop is totally symmetrical and the number of ones and zeros is equal. Light causes an asymmetry in the flip-flop that changes the ratio of ones and zeros. A fully digital output is obtained by counting the number of ones. A triangle-wave voltage is applied to the flip-flop to vary its threshold. The device showed that a large array of sensors with on-spot A/D (analog-to-digital) conversion can be realized using the flip-flop sensor technique     

Effect of Rare Earth on the Corrosion-Resisting Performance of Zinc-Based Alloy Coatings

The corrosion behavior of coatings of pure zinc and Zn-Al,Zn-Al-RE alloys in NaCl solu-tions was studied by salt-spray experiments,even corrosion experiments and electrochemical measurementsof bi-directional polarization curves and a.c.impedance in weak polarization region consistent regularitieswere obtained by these different methods,viz.,the corrosion resistance of Zn could be enhanced by alloying itwith Al,and particularly with Al-RE.The causes of enhancement of corrosion resistance by RE were alsodiscussed.     

预钙化处理后的钛表面磷灰石涂层的形成

本研究采用碱液处理钛样品 ,并进行预钙化处理 ,在模拟体液 (SBF)中浸泡 ,能在较短时间内形成表面致密的磷灰石涂层。碱液处理使钛表面生成了钛酸钠及氧化钛等物质 ,在SBF中浸泡时 ,会发生水解而使表面形成带负电的Ti OH基团。预钙化处理使带负电的钛表面由静电引力而聚集了大量的Ca2 + 离子。Ca2 + 能吸引带负电的HPO2 -4到达表面 ,从而使表面附近能在较短时间内达到钙 磷过饱和。Ca2 + 离子又能使表面附近的pH值增大 ,Ca2 + 离子和HPO2 -4离子的活度积就增大 ,从而刺激了磷灰石晶体的成核与长大 ,最终形成表面磷灰石涂层     

北洺河铁矿生产勘探网度的探讨

通过对生产勘探目的、任务及重要性的分析，介绍了确定生产勘探网度常用的类比、验证、统计3种方法，并选择合适北Ming河铁矿的类比法，结合具体情况及其它原则，初步确定了该矿的生产勘探网度，并对以后应用中应注意的问题提出看法。     

新型电场差分仪采集模块

文章主要介绍新型电场差分仪采集模块的实现方法。通过对四种频率的四道／二道、二次放电曲线的采集，采用自动调零、多次叠加、跟踪放大、来进一步提高测量精度，克服零漂、５０Ｈｚ工频干扰。该方法在河南油田试验中，效果很好。     

电弧炉冶炼超高强度凹螺纹钢筋钢工艺的探讨与研究

用电弧炉冶炼超高强度凹螺纹钢，钢中气体含量易偏高而造成氢脆和时效，从而影响钢的质量，通过冶炼工艺，采用钢包吹氩等措施，改善了钢的质量，满足了钢材的性能要求。     

广州白云国际会议中心真空排水系统设计简介

广州白云国际会议中心地下室设有7个公共卫生间和11个化妆间,排水系统选用了真空排水系统.介绍了其真空排水系统的设备配置、组成、动作过程、用电量、维护等,比较了真空排水系统与传统设集水井采用潜水泵抽升污水的方式,最后总结了工程施工和调试中出现的问题及解决方法.认为真空排水系统较传统排水系统技术先进,应在有条件的前提下大力推广应用.     

CaTiO_3∶Pr~(3+)的合成及发光特性

本文采用高温团相反应合成TCaTiO3∶Pr3+红色发光材料、报道了Pr3+激活的CaTiO3的光谱特征及长余辉特性，并与CaS∶Eu的光谱特性及长余辉进行了比较。CaTiO3∶Pr3+将是一种具有广泛用途的新材料     

管内不可压缩流体动态传送模型的简化

通过复频域分析，从理论上提出了一种建立输送管内不可压缩流体动态传送简化模型的方法。仿真结果表明，用本文提出的简化模型能较好地逼近基于偏微分方程的严格模型，且结构简单易于应用。在催化裂装置主分馏塔顶部模型的应用结果表明，本方法是可行的。