灰度图像的子块压缩方法

从灰度图像的局部几何特性出发，把图像中像素灰度相近或相同的区域当作一个整体处理，从而达到图像压缩的目的。计算机仿真实验表明，该方法可以获得产高的压缩比和峰值信噪比，有效地消除方块效应，很好地保持目标细节，具有较高的实用价值。     

Goppa geometric codes achieving the Gilbert-Varshamov bound

Based on s-zeta-functions of curves over finite fields, we show that Goppa geometry codes achieve the q-ary Gilbert-Varshamov bound for all prime powers q (including q=2)     

高压脉冲放电处理含氰废水的影响因素探讨

焦化废水中含有大量的氰化物,必须采取有效措施进行去除,传统去除方法运行成本高、操作复杂。提出了用高压毫微秒脉冲产生的非平衡等离子体处理含氰废水的方法,对其影响因素pH值、放电时间、气流量、放电条件等进行了大量的实验研究,结果表明:溶液初始pH值为9.09,放电2 h,放电电压46 kV时氰化物的去除率最高可达93.2%,氰化物质量浓度可降至0.26 mg/L。实验对比了放电与不放电氰化物的去除效果:相同条件下放电后氰化物的去除率大大提高,为焦化废水中氰化物的去除提出了一种新的方法。     

公路边坡培植柠条的探讨

介绍了河曲公路所处的自然环境 ,阐述了人工铲草的利与弊 ,进而提出了边坡培植柠条的效益分析 ,并对培植柠条的苗期管理及与养护生产的关系进行了介绍     

10kV配电室操作控制电源电压下降的解决措施

本提出了10kV配电室操作电压下降的现场解决方案。     

Grazing incidence reflection absorption Fourier transform infrared (GIRA-FTIR) spectroscopic studies on the ferroelectric behavior of poly(vinylidene fluoride–trifluoroethylene) ultrathin films

Grazing incidence reflection absorption Fourier transform infrared (GIRA-FTIR) spectroscopy was used to characterize the ferroelectric behavior of a thin poly(vinylidene fluoride–trifluoroethylene) P(VDF–TrFE) copolymer. The lab-built GIRA-FTIR apparatus allowed the heating and corona poling process to be carried out whilst collecting the GIRA spectra of the thin polymer film. The Curie transition from the ferroelectric to paraelectric phase was confirmed from the abrupt change in intensity of the 849 cm⁻¹ band in the RA-FTIR spectrum. It was found that the Curie temperature dropped dramatically when the film thickness was lowered to below a certain critical value of approximately 100 nm. The switching of the CF₂ dipoles in the ferroelectric crystals after applying the external electric field could be determined by monitoring the change in the 849 cm⁻¹ band intensity. For the 600 nm thick P(VDF–TrFE) film, the switching of the dipoles appears to occur almost instantaneously, while the kinetics of dipole switching of the 75 nm thick film were significantly retarded. The repeated switchability of the CF₂ dipoles upon the application of a bipolar cyclic electric field was also confirmed. The bistability of the film due to remnant polarization was also confirmed from the absorbance of the 849 cm⁻¹ band after removing the applied voltage during corona poling.     

地球化学录井技术的发展和应用

简要介绍了国内地化录井技术的发展历程，分析了该技术的特点及在油气勘探开发应用中取得的成效。认为中国地化录井技术在引进、消化、吸收的基础上，扩展了该技术的应用领域和范围，目前该专业的整体技术水平处于国际领先地位。在以统计资料及应用实例报道该技术的应用成果及独特技术优势的同时，也分析了存在的问题，指出了解决问题的主要途径。     

负载型固体碱催化合成亚苄基丙酮

研究了用固体碱 KOH/Al_2O_3催化合成苯叉丙酮,确定了合成的最佳工艺条件:n(苯甲醛)∶n(丙酮)=1∶4.催化剂用量2g,催化剂最佳负载量12mmol/g,反应温度40～45℃,反应时间为3h,产率达88%以上。     

工程造价管理经验在房地产中的应用

随着近几年我国房地产事业蓬勃发展，因此研究和探讨工程概预算的技术数据是项目管理工作中的重要信息，也是房地产加强工程造价有效控制的重要途径，本文结合工作实际，就如何积累工程造价经验数据，谈一点个人的体会。     

PVC树脂聚合用有机过氧化物引发剂

介绍了目前国内外引发剂的使用及开发方向,并对引发剂的选择及其对树脂质量的影响进行了讨论。