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Physico-chemical characterization of a farmland affected by wastewater in relation to heavy metals

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2008年第3期9卷 366-372页

作者： Emmanuel u. ONWEREMADu Department of Soil Science and Technology Federal university of Technology PMB 1526 Owerri Nigeria

This study investigated selected properties of soils affected by wastewater and its relationship with some heavy metals. A free survey technique involving target sampling was used in siting soil profile pits. Soil samples were collected based on horizon differentiation and analyzed using routine and special analytical techniques. Soil data were subjected to correlation analysis using SAS program. Results show that all heavy metals studied had values above critical limits in the polluted soils using known standards and that these biotoxic metals decreased with soil depths. Highly significant (P=0.01 and 0.05) relationships were established between investigated heavy metals and some soil properties, especially soil pH and organic matter. Further studies involving more edaphic properties, biotoxic metals and their bioaccessibility in crops growing on wastewater soils will surely enhance knowledge and management of these highly anthropogenically influenced soils of the study site.

关键词： Bioavailability Characterization Heavy metals Soil pollution Wastewater

Semi-solid near-net shape rheocasting of heat treatable wrought aluminum alloys

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1719-1724页

作者： u.A.C uRLE Materials Science and Manufacturing Council for Scientific and Industrial Research

Flexibility of the CSIR-RCS, induction stirring with simultaneous air cooling process, in combination with high pressure die casting is successfully demonstrated by semi-solid rheocasting of plates performed on commercial 2024, 6082 and 7075 wrought aluminum alloys. Tensile properties were measured for the above mentioned rheocast wrought aluminum alloys in the T6 condition. The results showed that tensile properties were close to or even in some cases exceeded the minimum specifications. The yield strength and elongation of rheocast 2024-T6 exceeded the minimum requirements of the wrought alloy in the T6 condition but the ultimate tensile strength achieved only 90% of the specification because the Mg content of the starting alloy was below the commercial alloy specification. The strengths of rheocast 6082-T6 exceeded all of the wrought alloy T6 strength targets but the elongation only managed 36% of the required minimum due to porosity, caused by incipient melting during solution heat treatment, and the presence of fine intermetallie needles in the eutectic. The yield strength of rheocast 7075 exceeded the required one and the ultimate tensile strength also managed 97% of the specification; while the elongation only reached 46% of the minimum requirement also due to incipient melting porosity caused during the solution heat treatment process.

关键词： high pressure die casting (HPDC) aluminum alloys as-cast condition T6 treatment incipient melting

苏鲁超高压变质岩的构造热历史:中国大陆科学钻探工程(CCSD)主孔(MH)和先导孔(PP2)的磷灰石裂变径迹约束

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岩石学报 2009年第7期25卷 1612-1618页

作者：刘顺生 glasmacher ulrich 许志琴 WEBER ursula WAGNER Günther JONCKHEERE Raymond 殷秀兰中国科学院广州地球化学研究所广州510640 Max-Planck-Institut für Kernphysik Ruprecht-Karls universitt Heidelberg 中国地质科学院地质研究所北京100037 中国地质科学院地质力学研究所北京100081

本文包括中国大陆科学钻(CCSD)主孔(MH)0～5000m和先导孔(PP2)0～1000m的磷灰石裂变径迹分折结果,先导孔PP2的裂变径迹表观年龄变化范围为79.5±5.1～50.4±6.2Ma,主孔的裂变径迹表观年龄变化范围为98.6±17.0～2.9±2.0Ma,主孔在4200m... 详细信息

本文包括中国大陆科学钻(CCSD)主孔(MH)0～5000m和先导孔(PP2)0～1000m的磷灰石裂变径迹分折结果,先导孔PP2的裂变径迹表观年龄变化范围为79.5±5.1～50.4±6.2Ma,主孔的裂变径迹表观年龄变化范围为98.6±17.0～2.9±2.0Ma,主孔在4200m以下,磷灰石样品中实际上已不存在自发裂变径迹,表明裂变径迹时钟已经"置零"。实验资料表明,裂变径迹表观年龄值随样品深度的增加而逐渐减少,直到一定深度,即达到磷灰石的裂变径迹封闭温度(～120℃)以后,年龄值为零。根据主孔0～2000m和先导孔0～1000m的裂变径迹年龄剖面,作为一级近似,计算出超高压变质岩体在90～30Ma期间,平均隆升速度为～35m/Ma。对主孔测定了9个样品的约束径迹(Confined track)长度,样品约束径迹平均长度的变化范围约为13.1μ7.4μm,总的变化趋势是:约束径迹平均长度随样品深度的增加而逐渐减少。样品的约束径迹长度分布都具有双峰型特征。根据裂变径迹年龄和约束径迹长度的资料,应用计算机模拟得到了样品的时间-温度(t-T)轨迹。结果表明,岩体从早白垩世(～120Ma)快速冷却以后,在晚白垩世和始新世又经历了两次加热作用,始新世末岩体所达到的温度大约是80℃,随后岩体则一直上升和缓慢冷却到现今所处的位置。在最后～30Ma岩体的平均隆升速度为～53m/Ma。

关键词：中国大陆科学钻探工程裂变径迹年龄测定热年代学超高压变质带磷灰石东海

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高乙烯含量VAE乳液的研究与生产

安徽化工 2024年第1期50卷 80-85页

作者：吴尚宋孟璐安徽皖维高新材料股份有限公司安徽巢湖238002

以聚乙烯醇(PVA1788、PVA0588)复配做保护胶体,醋酸乙烯酯及乙烯为单体,采用氧化还原法制备不同乙烯含量的VAE乳液。研究原料、聚合工艺和反应条件及加料方式对VAE乳液乙烯含量、固含量、粘度、玻璃化转变温度和相对分子质量的影响,考... 详细信息

以聚乙烯醇(PVA1788、PVA0588)复配做保护胶体,醋酸乙烯酯及乙烯为单体,采用氧化还原法制备不同乙烯含量的VAE乳液。研究原料、聚合工艺和反应条件及加料方式对VAE乳液乙烯含量、固含量、粘度、玻璃化转变温度和相对分子质量的影响,考查改性PVA对VAE乳液耐水性能的影响。结果表明,最佳初始反应温度为65℃,后期温度为70℃~85℃,最佳乳化剂含量为4%,最佳引发剂用量为2.5%,VAE乳液的乙烯含量为9%~23%,使用疏水基改性PVA代替部分保护胶体,乳液耐水性明显提高。

关键词：醋酸乙烯酯乙烯高乙烯含量VAE乳液改性PVA

维普期刊数据库博看期刊

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城市与自然之间嘉兴种子艺术中心

室内设计与装修 2024年第2期 24-27页

作者： B.L.u.E.建筑设计事务所 B.L.u.E.建筑设计事务所

种子艺术中心位于嘉兴市南湖区,距离市中心东侧10 km,处在城市与自然的过渡边界。项目定位为地产配套设施,近期作为附近社区的展示中心与零售空间,未来则活用为周边共享的邻里中心。艺术中心周围一半是农场与公园,一半是住宅与商业街,... 详细信息

种子艺术中心位于嘉兴市南湖区,距离市中心东侧10 km,处在城市与自然的过渡边界。项目定位为地产配套设施,近期作为附近社区的展示中心与零售空间,未来则活用为周边共享的邻里中心。艺术中心周围一半是农场与公园,一半是住宅与商业街,不同方位面向不同的景观与氛围,形成多元、生动的场所感。四周道路交会,人流聚集于此,是整个片区最具活力的核心点位。

关键词：邻里中心场所感嘉兴市南湖区配套设施商业街展示中心项目定位零售空间

Photoproduction of multi-meson final states–recent results from the Crystal-Barrel/TAPS experiment at ELSA-

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Chinese Physics C 2009年第12期33卷 1105-1112页

作者： u. Thoma HISKP Universitt Bonn Nussallee 14-16 53115 Bonn Germany

Multi-meson final states such as γp →pπ0π0 and γp →pπ0η have been investigated with the Crystal-Barrel/TAPS experiment at ELSA. Baryon cascades via △π and △η and also via higher mass baryon resonances are clearly observed. Based on this data and on data from other reactions a partial wave analysis has been performed from which partial decay widths of various N＊ and △＊ states into the different pπ0π0 and pπ0η decay channels have been determined, leading partly to unexpected results. In addition, polarisation observables have been investigated. The beam asymmetry X has been determined for both reactions and double polarisation data using a longitudinally polarised target and a circularly or linearly polarised photon beam has been taken. Given the angular coverage of the Crystal-Baxrel/TAPS experiment this data covers almost the full angular range and phase space. This data will provide new and important information for the partial wave analyses and bring us one step closer towards a complete experiment.

关键词： baryon spectroscopy photoproduction multi-meson final states polarisation observables

ADVANCED NICKEL-BASED AND NICKEL-IRON-BASED SuPERALLOYS FOR CIVIL ENGINEERING APPLICATIONS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 453-462页

作者： u. Brill ThyssenKrupp VDM GmbH 58791 Werdohl Germany

The use of high-temperature materials is especially important in power station construction, heating systems engineering, furnace industry, chemical and petrochemical industry, waste incineration plants, coal gasification plants and for flying gas turbines in civil and military aircrafts and helicopters. Particularly in recent years, the development of new processes and the drive to improve the economics of existing processes have increased the requirements significantly so that it is necessary to change from well-proven materials to new alloys. Hitherto, heat resistant ferritic steels sufficed in conventional power station constructions for temperatures up to 550℃ newly developed ferritic/martensitic steels provide sufficient strength up to about 600 - 620℃. In new processes, e.g. fluidized-bed combustion of coal, process temperatures up to 900℃ occur. However, this is not the upper limit, since in combustion engines, e.g. gas turbines. Material temperatures up to 1100℃ are reached locally. Similar development trends can also be identified in the petrochemical industry and in the heat treatment and furnace engineering. The advance to ever higher material temperatures now not only has the consequence of having to use materials with enhanced high-strength properties, considerable attention now also has to be given to their chemical stability in corrosive media. Therefore not only examples of the use of high-temperature alloys for practical applications will be given but also be contributed to some general rules for material selection with regard to their high-temperature strength and corrosion resistance.

关键词： nickel-based alloy high-temperature strength high-temperature corrosion resistance civil engineering application

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider u.Schramm M.E.P.umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Numerical Optimization of Pressure Force from Multiple Jets Impinging on a Moving Curved Surface for Industrial Drying Machines

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Open Journal of Fluid Dynamics 2021年第4期11卷 192-209页

作者： Ali Chitsazan Georg Klepp Mohammad Esmaeil Chitsazan Birgit glasmacher Institute for Energy Research Ostwestfalen-Lippe University of Applied Sciences and Arts Lemgo Germany Research Institute of Education Ahvaz Iran Institute for Multiphase Processes Leibniz University Hannover Hannover Germany

Jet force on the surface is typical for impinging jets towards the surface and it is very important in drying applications for force-sensitive surfaces. The designer should optimize the design parameters of industrial drying equipment to achieve minimum pressure force between multiple jets and a moving curved surface. SST k-ω turbulence model is used to simulate a real geometry for industrial drying applications. The SST k-ω turbulence model succeeded with reasonable accuracy in reproducing the experimental results. The jet to surface distance, jet to jet spacing, jet inlet velocity, jet angle, and surface velocity are chosen as the design parameters. For the optimization of the impinging round jet, the pressure force coefficient on the moving curved surface is set as the objective function to be minimized. The SHERPA search algorithm is used to search for the optimal point from the weighted sum of all objectives method. One correlation is developed and validated for the pressure force coefficient. It is found that the pressure force coefficient is highly dependent on the nozzle to surface distance and jet angle but relatively insensitive to jet inlet velocity, jet to jet spacing, and surface velocity. The minimum pressure force coefficient correlates with a high value of nozzle to surface distance (tenfold diameter in this analysis) and a low value of the jet angle (40? in this analysis). The agreement in the prediction of the pressure force coefficient between the numerical simulation and developed correlation is found to be reasonable and all the data points deviate from the correlation approximately 8% on average.

关键词： Multiple Jets Pressure Force Surface Motion Surface Curvature CFD Optimization