协同氧化光度法测定废水中微量铬(Ⅵ)

室温下,硫酸介质中,利用铬（Ⅵ）和高碘酸钾协同氧化二苯胺磺酸钠使其显色,建立了灵敏简便地测定微量铬（Ⅵ）的新方法.测定铬（Ⅵ）的线性范围为0.005～0.6mg/L,ε=1.11×105L/mol·cm.用于废水中铬（Ⅵ）的测定,结果满意.     

新型激光显示扫描系统设计

阐述了一种新型激光显示扫描系统的设计。根据光线反射定律，提出了采用多面转镜和二次反射面相互配合来实现光束在屏上线性扫描的系统模型。利用该模型，可以避免使用传统激光电视中的高速转镜装置，有较强的现实意义。在此基础上，提出了2种实现方案，对其分别建立了模型，并进行了模拟，计算了屏上光点位置、束斑大小、进行了数据分析，最终确定等边转镜和不规则二次反射面的配合，是一种实现扫描显示的方案。     

关于滞后广义系统的稳定与镇定

本文对滞后广义系统的稳定与镇定研究进展情况进行了综述。     

皖西北地区何首乌种植、销售及研究状况的调查

本文在实地考察和广泛咨询的基础上,概述了名贵中草药何首乌的生理特性及栽培管理技术,同时就其在皖西北地区的栽培、销售及研究状况进行了调查,并提出了充分发挥地区优势,建立何首乌栽培生产基地的建设性意见,对推动地方农村经济的发展与中药材市场的繁荣具有重要的指导意义。     

Effect of Al<Subscript>2</Subscript>O<Subscript>3sf</Subscript> addition on the friction and wear properties of (SiC<Subscript>p</Subscript>+Al<Subscript>2</Subscript>O<Subscript>3sf</Subscript>)/Al2024 composites fabricated by pressure infiltration

Aluminum (Al) 2024 matrix composites reinforced with alumina short fibers (Al₂O_3sf) and silicon carbide particles (SiC_p) as wear-resistant materials were prepared by pressure infiltration in this study. Further, the effect of Al₂O_3sf on the friction and wear properties of the as-synthesized composites was systematically investigated, and the relationship between volume fraction and wear mechanism was discussed. The results showed that the addition of Al₂O_3sf, characterized by the ratio of Al₂O_3sf to SiC_p, significantly affected the properties of the composites and resulted in changes in wear mechanisms. When the volume ratio of Al₂O_3sf to SiC_p was increased from 0 to 1, the rate of wear mass loss (K_m) and coefficients of friction (COFs) of the composites decreased, and the wear mechanisms were abrasive wear and furrow wear. When the volume ratio was increased from 1 to 3, the COF decreased continuously; however, the K_m increased rapidly and the wear mechanism became adhesive wear.     

Effect of different deformation and annealing procedures on non-magnetic textured Cu<Subscript>60</Subscript>Ni<Subscript>40</Subscript> alloy substrates

In this work, a series of specimens was prepared by the casting method. Sharp cube-textured substrates were processed by heavy cold rolling and recrystallization annealing (i.e., the rolling-assisted biaxially textured substrates (RABiTS) method). Both the rolling and the recrystallization texture in the alloy tapes were investigated by X-ray diffraction and electron back-scatter diffraction, respectively. The results showed that a strong copper-type deformation texture was obtained in the heavy cold-rolled substrate. In addition, the recrystallization annealing process was found to be very important for the texture transition in the Cu–Ni alloy substrates. The cube texture content in the Cu₆₀Ni₄₀ alloy substrates reached 99.7% (≤10°) after optimization of the cold-rolling procedure and the recrystallizing heat-treatment process, whereas the content of low-angle grain boundaries (from 2° to 10° misorientation) in the substrate reached 95.1%.     

Prediction model for atmospheric corrosion of 7005-T4 aluminum alloy in industrial and marine environments

Accelerated corrosion tests of the 7005-T4 aluminum alloy were conducted to determine a suitable service life prediction method by using alternating wet-dry cycles in three kinds of solutions. The morphology and composition analysis of the corrosion product revealed that slight corrosion occurred on the surfaces of the samples immersed in a 0.25wt% Na₂S₂O₈ solution. However, pitting corrosion occurred on the surfaces of the samples immersed in a 3.5wt% NaCl solution, whereas exfoliation corrosion occurred on the surfaces of the samples immersed in a mixture of 0.25wt% Na₂S₂O₈ and 3.5wt% NaCl solutions. A power exponent relationship was observed between the mass loss and exposure time of the 7005-T4 aluminum alloy immersed in the three kinds of solutions. In the mixture of 0.25wt% Na₂S₂O₈ and 3.5wt% NaCl solutions, the mass loss of the aluminum alloy yielded the maximum value. Based on the calculation of the correlation coefficients, the alternating wet-dry procedure in a 3.5wt% NaCl solution could be used to predict the corrosion behavior of 7005-T4 aluminum alloy exposed in the atmosphere of Qingdao, China. The prediction model is as follows:T=104.28·t0.91, where T is the equivalent time and t is the exposure time.     

宁夏居民体育健身活动及变动项目因素分析

经调查研究表明,宁夏居民体育健身活动项目主要集中在散步、跑步、气功、太极拳、体操(徒手体操)、羽毛球、乒乓球、体育舞蹈上,随年龄的增长部分活动项目的参与率呈上升趋势,部分活动项目的参与率呈明显下降趋势,部分活动项目的参与率则呈上下起伏不定态势．     

多禁止符号算术编码高效错误检测算法

为解决算术编码误码敏感的问题,提出了采用多个禁止符号的高效算术编码错误检测方法。在分析有限精度算术编码器特点的基础上,研究了多禁止符号的不同概率区间分配方案,比较了各种方案错误检测的符号距离和bit距离。实验结果表明:在添加相同程度的编码冗余情况下,多禁止符号错误检测方法优于单个禁止符号检测方法,可更快检测出错误,错误符号被立即检测出的比例提高了约一倍。多个禁止符号错误检测方法能够高效、快速地检测出传输中产生的比特错误,对通信中的检错重传、算术编码联合译码、错误定位等都有意义。     

內源微生物驱后油藏理化性质变化及细菌群落结构解析?

通过研究新疆油田微生物驱后油水两相理化性质,发现现场注入营养剂后采出液水相黏度升高50%以上,油相黏度降低54%,油水两相界面张力降低了24%。通过比较两种细胞破碎方法提取的采出水中细菌总DNA质量,确定使用以超声波细胞破碎法所提取的水样总DNA扩增细菌16S rDNA高可变区V9区,利用变性梯度凝胶电泳（Denaturing Gradient Gel Electrophoresis,DGGE）法根据DNA片段裂解性质分析不同时期采出水菌群变化。通过对优势条带序列的分析及在GenBank中的比对,发现现场营养剂激活后菌群构成趋向简单化,激活后微生物采油常用功能菌假单胞菌属（Pseudomonas）和梭菌(Clostridium)为优势菌。说明通过现场营养剂的注入,定向激活了有益功能菌,改善了油藏油水流度比,这些都是油田现场采收率提高的原因。