含腐植酸喷施宝叶面肥降解土壤农药残留探讨

研究结果表明,含腐植酸喷施宝叶面肥对降低土壤中草甘膦、乙草胺、三唑磷残留量有显著的促进作用,在使用草甘膦、乙草胺、三唑磷3种农药时,加入含腐植酸喷施宝叶面肥1500～2000倍,药后3天、7天采样土壤样品检测,在喷施等量农药下,添加含腐植酸喷施宝叶面肥,与不添加为对照相比:土壤中草甘膦的残留量降低16.52%、17.98%;乙草胺残留量降低42.98%、69.71%;三唑磷残留量降低24.49%、39.04%,检测结果经t测验,其差异均达到显著水平(P<0.01)。     

New Method of Synthesizing Aluminum Oxynitride Spinel Powders

Aluminum oxynitride spinel (AlON) powders were synthesized by aluminothermic reaction in a reducing N₂‐CO atmosphere. Low cost and easily available aluminum and γ‐Al₂O₃ alumina micrometer‐sized powders were employed as starting materials. Mixed powders consisting of 75 wt% Al and 25 wt% Al₂O₃ were milled together and pressed into billets with diameter of 20 mm and height of 15 mm. Green‐body billets were then calcined in charcoal‐protected condition (namely in a N₂‐CO atmosphere) at 1600°C. Phase composition and microstructure of final sintered products were analyzed. The results showed that AlON phase with AlN as a minor phase was formed at 1600°C for 3 h. At the same time, grains of AlON were tabular in shape and whiskers can be found in samples after being sintered at 1600°C.     

基于MATLAB的球面干涉仪图像处理系统设计

采用泰曼-格林干涉原理设计研制了一种非接触在线球面干涉仪,该干涉仪中的CCD摄像头可产生分辨率比较高的干涉条纹图像。重点介绍了用MATLAB图像处理软件对该干涉条纹图像进行数字化处理的基本方法,通过对干涉条纹图像进行预处理、提取骨架,最后用Zernike多项式拟合出被检球面的波面函数,计算出PV和RMS。通过MATLAB编程实现了对该球面干涉仪检测信号的自动化处理。     

有限域上超椭圆曲线离散对数问题的错误攻击

In this paper, we present two explicit inva-lid-curve attacks on the genus 2 hyperelliptic curve o-ver a finite field. First, we propose two explicit attack models by injecting a one-bit fault in a given divisor. Then, we discuss the construction of an invalid curve based on the faulted divisor. Our attacks are based on the fact that the Hyperelliptic Curve Scalar Multiplica-tion (HECSM) algorithm does not utilize the curve parameters and We consider three hyperelliptic curves as the attack targets. For curve with security level 186 (in bits), our attack method can get the weakest inva-lid curve with security level 42 (in bits); there are 93 invalid curves with security level less than 50. We al-so estimate the theoretical probability of getting a weak hyperelliptic curve whose cardinality is a smooth integer. Finally, we show that the complexity of the fault attack is subexponential if the attacker can freely inject a fault in the input divisor. Cryptosystems based on the genus 2 hyperelliptic curves cannot work against our attack algorithm in practice.     

斜轧穿孔法制备TC4合金管坯

为了供给市场要求的大直径TC4钛合金异型管壳的二次成形坯料,采用斜轧穿孔加工工艺制备了符合需求的TC4管坯。原始材料为自耗电弧熔炼铸锭,铸锭在β和α＋β相区锻造成Ф100mm×700mm的棒坯。穿孔前棒坯在中频感应炉中经980℃,3min热处理,然后在加强型两辊斜轧穿孔机上一火穿成Ф102mm×11mm×1700mm管坯。所制成的管坯表面光滑,外径尺寸公差达到0．35mm,壁厚公差达0．1mm。管坯退火态室温下Rm=945MPa,A=14％,Z=33％。其强度比挤压制备的管坯略高,塑性相当。实验结果表明,采用斜轧穿孔法完全可以制备符合标准要求的大直径TC4管坯。     

电炉变压器级差保护器的设计

电炉变压器在冶炼过程中调压范围大,分接开关动作频繁,容易出现电压级差故障,损坏变压器。4西方介绍了其控制电路中增设的级差保护器的设计原理,它能有效地监督控变压器的运行,防止变压器的损坏。     

尼龙6共混改性研究进展

系统介绍了国内外用聚乙烯、聚丙烯、PVDF、PAR、PET、PVOH、ABS、PC、PPO、SAN、弹性体、TLCP等改性尼龙 6的系列方法、研究成果及其性能 ,并提出了反应挤出共混改性和无机纳米材料改性尼龙 6的设想     

对中原油田注水节能降耗的探讨

中原油田经过多年的实践和探索 ,对大型注水离心泵的电机匹配 ,有了一些经验 ,如濮三联注水站 ,随着注水量的不断增加 ,原D2 5 0型注水泵 (3台 )改为D30 0型后 ,将原电机功率 16 0 0kW增加至 180 0kW ,既满足了生产工艺的要求 ,又节省了二次投资 ,同时也提高了泵效。 1993年以后 ,先后在濮三联、胡二注、卫城等站将D2 5 0型改为D30 0或D40 0型注水泵 ,使泵运行效率提高到 78%左右。设计人员通过多年的探索 ,根据中原油田各区块的注水特点 ,采用了整体降压和局部增压相结合的方法 ,使离心泵站的注水压力保持在 16～ 17MPa ,即可满足常压注水井 (17MPa以下 )的要求 ,部分注水井 (2 0MPa以上 )采用单井增注或建增注站的方式 ,这样不仅提高了管网运行效率 ,还可以节约大量的电能和运行费用     

微裂缝性特低渗透油藏储层特征研究

将不同渗透率的含微裂缝与相同渗透率、不含微裂缝低渗透砂岩岩心进行了对比,研究了微裂缝性特低渗透油藏的孔隙空间形态、喉道半径、微观均质系数和相对分选系数等特征,分析了这些特征对孔隙度渗透率性质、可动流体体积和压力敏感性等方面的影响。结果表明,微裂缝性特低渗透砂岩孔道与孔道之间主要靠微裂缝连接,连通性较低,主要由微裂缝提供渗流能力。气测渗透率和微裂缝宽度、微观均质系数、相对分选系数和可动流体体积百分数等都有明显的幂律关系。孔隙度与渗透率相关性差,气测渗透率与水测渗透率比值较大,各向异性和非均质性严重,压力敏感性较强。渗透率低不是低渗透油藏的本质特征,只是外在表现形式之一。应该根据微观孔隙结构特征、可动流体体积百分数和压力敏感特征等多个因素综合评价其储层特征。     

基于超亲水原理的自清洁表面研究进展及产业化状况

简要介绍了超亲水表面的自清洁原理、各种制备方法及目前超亲水自清洁表面的产业化状况.从初始接触角、光谱响应范围和超亲水持久性角度出发,指出了当前超亲水自清洁表面研究中存在的问题.最后对其未来发展进行了展望.