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Wear of the working parts of agricultural tools in the context of the mass of chemical elements introduced into soil during its cultivation

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International Soil and Water Conservation Research 2021年第2期9卷 229-240页

作者： Piotr Kostencki Tomasz Stawicki Aleksandra krolicka Department of Renewable Energy Engineering Faculty of Environmental Management and AgricultureWest Pomeranian University of Technology in SzczecinPapie_za Pawła VI Street 171-459SzczecinPoland Faculty of Mechanical Engineering Wrocław University of Science and TechnologySmoluchowskiego Street 2550-370WroclawPoland

For the manufacture of working parts of agricultural tools operating in soil,various structural materials are used:alloy and low-alloy steels,weld materials for hardfacing,and plates made from *** design new construction solutions to obtain components that are resistant to abrasive wear and *** components are subject to wear during soil cultivation,due to which wear products remain in the *** this work,the mass of chemical elements remaining in soil from materials used in selected working parts of agricultural tools intended for soil cultivation was *** the operation of the tested parts,it was found that the following elements were introduced into the soil:Al,B,C,Co,Cr,Cu,Fe,Mo,Nb,Ni,P,Pb,S,Si,ti,V,Wand *** was introduced into the soil in the highest amount(15.907e222.004 g∙ha-1).Among the chemical elements reaching the soil,there were also elements that may pose a toxicological *** was found that the mass of chemical elements introduced into the soil depends on their content in the used structural materials and also on the conditions of cultivation,which determine the wear intensity of the parts.

关键词： Soil cultivation Working parts Potentially toxic elements Soil contamination Cemented-carbide Low-alloy steel

X-Ray and Mössbauer Study of Magnetic Black Sand from Mayotte Island

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World Journal of Nuclear Science and Technology 2016年第4期6卷 191-198页

作者： Saverio Braccini Karl krämer Stephane Chapenoire Albert Einstein Center for Fundamental Physics (AEC) Laboratory for High Energy Physics (LHEP) University of Bern Bern Switzerland Department of Chemistry and Biochemistry University of Bern Bern Switzerland Forensic and Criminal Intelligence Agency of the French Gendarmerie (IRCGN) Cergy-Pontoise France Pö le Odontologie et Santé Buccale CHU Bordeaux Bordeaux France ISPED Inserm U897 Bordeaux France

Natural magnetic black sands are known from several sites often located in areas of volcanic origin. Their elemental and mineral composition provides information on the geology of their territory and depends on several factors occurred during their formation. A sample of black sand was collected on the seashore of the island of Mayotte in the Indian Ocean and its magnetic part was investigated by means of energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (XRD), and MÖssbauer spectroscopy at room temperature. The mineral composition is dominantly magnetite, in good agreement with samples collected in other sites of volcanic origin. Contrary to pure magnetite, a relevant fraction of ti was detected by EDS. The 16% ti and 1% Mn content increase the magnetite lattice parameter to 8.4312 (25) Å. The broadening of XRD lines pointed towards a significant degree of disorder. This was confirmed by MÖssbauer spectroscopy and is attributed to the presence of ti replacing Fe in the magnetite lattice. The presence of ti modifies the local magnetic field on the Fe sites, leading to a broader and more complex MÖssbauer transmission spectrum with respect to the one of pure magnetite. To study the effect of temperature, samples were heated for 12 hours to 600°C and 800°C in argon and to 1000°C in air. Annealing in argon did not improve the crystallinity while annealing in air caused a complete decomposition of magnetite into hematite and pseudobrookite.

关键词： Magnetic Black Sand Iron Minerals Energy Dispersive X-Ray Spectroscopy X-Ray Diffraction Mössbauer Spectroscopy

Quasi-Static Problem of Thermoelasticity for Thermosensitive Infinite Circular Cylinder of Complex Heat Exchange

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Advances in Pure Mathematics 2013年第4期3卷 430-437页

作者： Halyna Harmatij Marta król Vasyl Popovycz Faculty of Mathematics and Applied Physics Rzeszow University of Technology Rzeszow Poland Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of Ukraine Lviv Ukraine

Nonlinear nonstationary heat conduction problem for infinite circular cylinder under a complex heat transfer taking into account the temperature dependence of thermophysical characteristics of materials is solved numerically by the method of lines. Directing it to the Cauchy’s problem for systems of ordinary differential equations studied feature which takes place on the cylinder axis. Taken into account the dependence on the temperature coefficient of heat transfer that the different interpretation of its physical content makes it possible to consider both convective and convective-ray or heat ray. Using the perturbation method, the corresponding thermoelasticity problem taking into account the temperature dependence of mechanical properties of the material is construed. The influence of the temperature dependence of the material on the distribution of temperature field and thermoelastic state of infinite circular cylinder made of titanium alloy ti-6Al-4V by radiant heat transfer through the outer surface has been analyzed.

关键词： Thermoelastic State Heat Transfer Boundary Value Problem

High-resolution ex vivo analysis of the degradation and osseointegration of Mg-xGd implant screws in 3D

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Bioactive Materials 2022年第7期7卷 37-52页

作者： Diana krüger Silvia Galli Berit Zeller-Plumhoff D.C.Florian Wieland Niccolo Peruzzi Bjorn Wiese Philipp Heuser Julian Moosmann Ann Wennerberg Regine Willumeit-Romer Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht21502Germany University of Malmo Faculty of OdontologyDepartment of ProsthodonticsCarl Gustafs vag 34Klerken20506MalmoSweden Lund University Department of Clinical Sciences LundMedical Radiation PhysicsBarngatan 422242LundSweden Deutsches Elektronen-Synchrotron(DESY) Notkestrasse 8522607HamburgGermany Institute of Materials Physics Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht21502Germany University of Gothenburg Institute of OdontologyDepartment of ProsthodonticsMedicinaregatan 12 f41390GoteborgSweden

Biodegradable magnesium(Mg)alloys can revolutionize osteosynthesis,because they have mechanical properties similar to those of the bone,and degrade over time,avoiding the need of removal ***,they are not yet routinely applied because their degradation behavior is not fully *** this study we have investigated and quantified the degradation and osseointegration behavior of two biodegradable Mg alloys based on gadolinium(Gd)at high ***-5Gd and Mg-10Gd screws were inserted in rat tibia for 4,8 and 12 ***,the degradation rate and degradation homogeneity,as well as bone-to-implant interface,were studied with synchrotron radiation micro computed tomography and ***(ti)and polyether ether ketone(PEEK)were used as controls material to evaluate *** results showed that Mg-5Gd degraded faster and less homogeneously than *** alloys gradually form a stable degradation layer at the interface and were surrounded by new bone *** results were correlated to in vitro data obtained from the same material and *** average bone-to-implant contact of the Mg-xGd implants was comparable to that of ti and higher than for *** results suggest that both Mg-xGd alloys are suitable as materials for bone implants.

关键词： Magnesium alloys Biodegradable implant Micro-computed tomography degradation rate Degradation homogeneity Ex vivo imaging Ex vivo histology Histology vs.tomography

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光致折变布拉格光栅实验研究

光学技术 2000年第4期26卷 375-376页

作者：裴丽谢增华宁提纲李唐军简水生北方交通大学光波所北京100044

本文介绍了 2 48nm、kr F准分子激光经过石英相位掩膜版的空间调制 ,在载氢增敏处理过的通信光纤与 B/Ge光纤上分别写入光致折变布拉格光栅的实验研究。经实验测定 ,在光栅布拉格波长上 (λH2 =15 46 .45 5 4nm ,λB/Ge=15 45 .15 5 nm... 详细信息

本文介绍了 2 48nm、kr F准分子激光经过石英相位掩膜版的空间调制 ,在载氢增敏处理过的通信光纤与 B/Ge光纤上分别写入光致折变布拉格光栅的实验研究。经实验测定 ,在光栅布拉格波长上 (λH2 =15 46 .45 5 4nm ,λB/Ge=15 45 .15 5 nm) ,两种光栅反射率均大于 99% ,3d B带宽分别为 0 .12 9nm和 0 .182 nm。经比较 ,B/

关键词：氢载光纤布拉格光栅光致折变光纤通道

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种子辐射处理对芝麻产量及农艺性状的影响

华北农学报 2000年第1期15卷 32-36页

作者：卫双玲张体德卫文星张海洋路凤银梅鸿献河南省芝麻研究中心河南郑州450002

以 4 0 ,6 0 ,8 0 ,10 0kr 4种剂量的6 0 Coγ射线对豫芝 4号、郑 95- 8、豫芝 11号 3个芝麻品种的风干种子进行辐射处理后播种。结果表明 :种子处理后芝麻产量提高 4 93%～ 2 2 30 % ;不同品种或同一品种对辐射处理的剂量... 详细信息

以 4 0 ,6 0 ,8 0 ,10 0kr 4种剂量的6 0 Coγ射线对豫芝 4号、郑 95- 8、豫芝 11号 3个芝麻品种的风干种子进行辐射处理后播种。结果表明 :种子处理后芝麻产量提高 4 93%～ 2 2 30 % ;不同品种或同一品种对辐射处理的剂量反应不同 ;各品种在其最佳剂量下 ,芝麻的农艺性状有所改进。

关键词：种子处理芝麻 γ-辐射农艺性状低剂量