Design of Watertight Barriers for Retention Ponds of Cyanide Using Sludge from Water Purification Station （Ziga）

In a context of sustainable development and use of eco- materials, it was examined the possibility of using sewage sludge from the water treatment plant of Ziga as an inorganic support to achieve sealing barriers that can withstand high stresses to overcome any weaknesses of the geological barrier （called passive barrier）. The station Ziga that potabilises the water from the river Nakamb6 is located 45 km north east of Ouagadougou. Some experiments on the rheology of sludge from Ziga as well as the filtration of the mixture Ziga＇s sludge and clays from Nouna, Zorgho and Ticare, three regions of Burkina Faso, were conducted. These studies demonstrated the complex hydro-mechanical behavior of Ziga＇s slurries： Newtonian fluid thixotropic threshold for solids contents less than 16.5 wt% and non-Newtonian for higher values. Sludge from the water treatment station Ziga have a hydraulic conductivity of 10^-8 m/s. The results are below regulatory requirements. However, the permeability can be reduced to achieve the value of 10^-9 m/s in particular by adding the clay from Zorgho or Nouna to mixtures of Ziga＇s sludge and neutral leachate, typically mineral water. Beside neutral leachate, two types of leachate were used. One type is composed of acid leachate and the other type is basic. It was shown that the limewater solutions cause deterioration of the seal probably due to the presence of hydroxide ions.     

Up-converting NaYF4：0.1%Tm^3＋, 20%Yb^3＋ nanoparticles as luminescent labels for deep-tissue optical imaging

Optical imaging plays an important role in biomedical research being extremely useful for early detection, screening and image-guided therapy. Lanthanide-doped up-converting nanoparticles were ideally suited for bioimaging because they could be ex- cited in near infrared （NIR） and emit in NIR or visible （VIS）. Here, we compared lanthanide doped up-converting NaYF4 and organic fluorophores for application in deep-tissue imaging. For that purpose - tissue phantoms mimicking the natural properties of light scat- tering by living tissues were prepared. The studies allowed to quantitatively compare optical resolution of different fluorescent com- pounds, revealing that the NIR photoexcitation was favorable over conventional UV photoexcitation.     

狙击小组:狙击手与观察手休戚与共

西方军队一直以双人狙击小组的编制形式出现:一人为狙击手,主要任务是使用狙击步枪实施狙杀;另一人为观察手,主要任务是使用观察器材对目标进行观察,并掩护狙击手的行动.而我军一直以来则采用单人单枪的编制形式.应该说,从现代狙击战术和技术的角度考虑,采用双人狙击编配更为科学合理,且双人在长期的训练及任务执行中要建立起高度默契关系,休戚与共.     

青州市西部山区旅游度假概念规划设计

青州市历史文化悠久，旅游资源丰富，物产丰饶，人杰地灵。青州西部山区环境优美，占据旅游资源与区位优势，适宜发展绿色休闲旅游度假，把青州西部山区、南燕国古城遗址资源加以开发，更好的呈现青州旅游的资源综合强势，打造青州历史文化名城。本文就青州市西部山区发展绿色旅游度假作了分析，重点对旅游度假项目规划提出了设想并对西部山区度假功能分区与旅游线路进行了规划设计。     

工业互联网的体系框架与关键技术——解读《工业互联网：体系与技术》

2017年连入互联网的设备数量首次超过全球人口数量,人类社会从此进入工业互联网时代。工业互联网时代将是一个人与人、人与机器、机器与机器全面互联的社会。以工业互联网时代为代表的信息革命将像工业革命一样,带来人类社会生产力的又一次飞速提高。由机械工业出版社于2018年出版的《工业互联网:体系与技术》一书介绍了互联网的发展历史,定义了工业互联网的体系架构,描述了互联网的4大关键技术,讨论了工业互联网时代的挑战与发展。本文概述了该书的主要论点。     

High Hole Mobility of GaSb Relaxed Epilayer Grown on GaAs Substrate by MOCVD through Interfacial Misfit Dislocations Array

The structural property of GaSb epilayers grown on semi-insulator GaAs (001) substrate by metalorganic chemical vapor deposition (MOCVD) using Triethylgallium (TEGa) and trimethylantimony (TMSb),was investigated by variation of the Sb:Ga (V/III) ratio.An optimum V/III ratio of 1.4 was determined in our growth conditions.Using transmission electron microscopy (TEM),we found that there was an interfacial misfit dislocations (IMF) growth mode in our experiment,in which the large misfit strain between epilayer and substrate is relaxed by periodic 90 deg.IMF array at the hetero-epitaxial interface.The rms roughness of a 300 nm-thick GaSb layer is only 2.7 nm in a 10 μm×10 μm scan from atomic force microscopy (AFM) result.The best hole density and mobility of 300 nm GaSb epilayer are 5.27×10 6 cm 3 (1.20×10 6) and 553 cm 2 ·V 1 ·s 1 (2340) at RT (77 K) from Hall measurement,respectively.These results indicate that the IMF growth mode can be used in MOCVD epitaxial technology similar to molecular beam epitaxy (MBE) technology to produce the thinner GaSb layer with low density of dislocations and other defects on GaAs substrate for the application of devices.     

四辊粗轧机支承辊面剥落的处理

文章通过对Φ330/Φ760×600mm四辊可逆粗轧机支承辊在生产过程中出现表面剥落故障的分析,提出了处理办法,指出合理设计轧辊对延长其寿命具有非常重要的意义。     

Effect of Ni7+ Ion Irradiation on Structure and Ammonia Sensing Properties of Thermally Oxidized Zinc and Indium Films

ZnO and In2O3 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respectively onto the glass substrate at 30 C. The fabricated films have been irradiated with 100-MeV Ni7+ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction (XRD) pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In2O3 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni7+ irradiated In2O3 films shows an improvement as compared to its pristine counterpart.     

Nano Sized Copper Selenide Thin Film Pre-Cursor by A Liquid Phase Chemical Growth Process

The deposition of copper selenide(CuSe)thin films was carried out using liquid phase chemical bath deposition process at the optimized growth parameters as:60℃deposition temperature,90 minutes deposition time,pH equal to 10.5±0.1 and 72±2 r/min speed of mechanical rotation.The as-grown deposits exhibited excellent uniformity and physical adherency with the substrate surface and are smooth and diffusely reflecting with colour changing from yellowish orange to dark chocolate during deposition.The layer is of the order of 300 nm thick.The EDS analysis technique gave film composition to be nearly stoichiometric(Cu=47.89%,Se=52.11%).An X-ray diffraction analysis showed CuSe to be polycrystalline hexagonal with a good match of d-values and intensities of reflections.The crystallite size is in the nanorange(50-60 nm).The as-deposited CuSe exhibited a high coefficient of absorption(α=105cm-1)with a direct optical band gap of 1.81 eV.Compared to other chalcogenides,CuSe films exhibit low resistance;room temperature electrical resistivity being 1.55×103?cm.The electrical conductivity decreased with increase in temperature up to 473 K;showing totally unusual behaviour from that of the semiconducting property.The thermo probe measurements showed n-type conduction of the samples.     

浅析中山电网线损计算

电网的线损率是电网公司管理水平的综合反映,中山电网的目标是做到技术线损合理,管理线损最小。文章用均方根电流法从线路和主变两个方面分析中山主电网的线损构成,提出了中山主电网线损的一些关键问题和解决措施。