Canadian Field Soils I. Mineral Composition by XRD/XRF Measurements

Forty Canadian soils were laboratory tested for the presence of quartz and other minerals using X-ray diffraction/X-ray fluorescence techniques. On average, the highest quartz content was observed in soil samples from sites in Nova Scotia followed by Prince Edward Island sites, whereas soil sample from British Columbia sites had the lowest quartz content. The second most abundant mineral was albite that mainly occurred in soil samples from Ontario and Quebec sites. Illite was the third most abundant and prevailed in soils mainly from British Columbia and New Brunswick sites. Soil samples from British Columbia sites had the highest combined clay and silt content and were composed of illite, albite, kaolinite, and chlorite. The lowest clay content was found in the samples from the Quebec sites. The highest microcline (a potassium feldspar) content was observed in Quebec, Ontario, and Prince Edward Island sites. In contrast to other provinces, samples from Quebec and Ontario sites also included amphibole. Soil samples from Saskatchewan and Manitoba sites also comprised carbonates, i.e., calcite and dolomite. Iron oxides (e.g., goethite) were present in all soils, except the Quebec sites, but their occurrence was rather insignificant.     

H.26L中整数变换的研究及改进

针对DCT变换存在浮点运算、运算量大等问题,H.26L提出了整数变换,它能够很好地消除浮点运算,避免逆变换不匹配,但存在精度不高的问题。在基于提升结构(liftingstructure)的无乘法二进制DCT(binDCT)的基础上,对参数进行选择优化,并将浮点DCT、整数变换和binDCT在结构和性能上进行比较分析,选择一组binDCT参数,使binDCT既能避免浮点运算又能降低运算量,且更有利于压缩。     

Improving the electrical and mechanical behavior of electrically conductive paint by partial replacement of silver by carbon black

Partial replacement of silver particles by carbon black (low cost) in electrically conductive paint was found to decrease the electrical resistivity and increase the scratch resistance of the resulting thick film, which is for use in electrical interconnections. An effective carbon black content is 0.055 of the total filler volume. By using a total solid volume fraction of 0.1969 and a silane-propanol (1:1 by weight) solution as the vehicle, a paint that gives a thick film with resistivity 2 × 10⁻³ Ω·cm has been attained.     

蛇形机器人整体设计与实现

文章主要描述蛇形机器人的设计,包括蛇形机器人的当前发展情况,蛇形机器人整体的设计与实现.实现设计时选用一种集电机、伺服驱动、总线式通讯接口为一体的SR518舵机,采用ARM嵌入式单片机stm32作为控制器,使用多种传感器增加蛇形机器人功能.     

A two-year measurement of rainfall attenuation of CW microwaves inSingapore

The authors present two-year statistics on the rainfall attenuation of 21.225 GHz vertically polarized CW microwave signals in Singapore. The CCIR recommendation is found to underestimate the microwave specific attenuation (dB/km) per path average rain rate (mm/h) as well as the accumulated time of attenuation exceeding preset levels. A negative exponential raindrop size distribution based on spherical droplets is constructed from the measured data     

成岩史模拟与成岩阶段预测——以黄骅坳陷碳酸盐岩为例

通过在时空领域内模拟镜质组反射率、古地温、伊/蒙混层中蒙皂石层含量和甾烷异构化率的变化，建立了碳酸盐岩成岩作用数值模拟系统。模拟结果表明，黄骅坳陷奥陶系碳酸盐岩在加里东期处于早成岩阶段，海西期-印支期处于中成岩阶段A期，燕山期进入中成岩阶段B期。古近纪-现今，奥陶系下部碳酸盐岩一直处于晚成岩阶段，但中、上部地层仍处于中成岩阶段。目前，在黄骅坳陷的北部和南部地区，奥陶系碳酸盐岩进入中成岩阶段B期，有利于天然气的生成与聚集；中部地区则处于中成岩阶段A期，可以生成和聚集液态烃，是石油勘探的有利地区。     

打靶法实现Lorenz-Haken激光混沌的周期和稳态控制

用打靶法对Lorenz-Haken单模激光混沌模型进行控制。计算机模拟结果表明,实现了Lorenz-Haken激光系统的周期一、周期二、周期四等周期轨道控制和稳态控制。     

A microcoded elliptic curve processor using FPGA technology

The implementation of a microcoded elliptic curve processor using field-programmable gate array technology is described. This processor implements optimal normal basis field operations in F(2/sup n/). The design is synthesized by a parameterized module generator, which can accommodate arbitrary n and also produce field multipliers with different speed/area tradeoffs. The control part of the processor is microcoded, enabling curve operations to be incorporated into the processor and hence reducing the chip's I/O requirements. The microcoded approach also facilitates rapid development and algorithmic optimization: for example, projective and affine coordinates were supported using different microcode. The design was successfully tested on a Xilinx Virtex XCV1000-6 device and could perform an elliptic curve multiplication over the field F(2/sup n/) using affine and projective coordinates for n=113,155, and 173.     

Synthetic Crystals of Silver with Carbon: 3D Epitaxy of Carbon Nanostructures in the Silver Lattice

Only minimum amounts of carbon can be incorporated into silver, gold, and copper in a thermodynamically stable form. Here, the structure of stable silver carbon alloys is described, which are produced by thermoelectrically charging molten silver with carbon ions. Transmission electron microscopy and Raman scattering are combined to establish that large amount of carbon is accommodated in the form of epitaxial graphene‐like sheets. The carbon bonds covalently to the silver matrix as predicted from density functional theory (DFT) calculations with bond energies in the range 1.1–2.2 eV per atom or vacancy. Graphitic‐like sheets embedded in the crystal lattice of silver form 3D epitaxial structures with the host metal with a strain of ≈13% compared to equilibrium graphene. The carbon nanostructures persist upon remelting and resolidification. A DFT‐based analysis of the phonon density of states confirms the presence of intense vibration modes related to the Ag? C bonds observed in the Raman spectra of the alloy. The solid silver–high carbon alloy, termed “Ag‐covetic,” displays room temperature electrical conductivity of 5.62 × 10⁷ S m^?1 even for carbon concentrations of up to ≈6 wt% (36 at%). This process of incorporation of carbon presents a new paradigm for electrocharging assisted bulk processing.     

Phragmites stimulation and natural attenuation of indigenous microbial community accelerated bioremediation of oil contaminated soil

Illumina high-throughput sequencing method was used to reflect fluctuation of indigenous microbial community during phragmites stimulation process in this study. Results showed Proteobacteria, Fimicutes, and Actinobacteria were most influential in process, Firmicutes and Deinococcus-Thermus were positively affected by nutrient amendment. Firmicutes can be seen as indicator of degradation rate. Dietzia, Salinimicrobium, and Halomonas were the most dominant genus in both Phragmites and Blank setups. These results indicated phragmites addition improved the efficiency of biodegradation and significantly regulated the microbial community structure and functions during remediation process.