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Li2SiO3 fast microwave-assisted hydrothermal synthesis and evaluation of its water vapor and C02 absorption properties

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Particuology 2016年第1期14卷 129-137页

作者： J. Ortiz-Landeros R. Lopez-Juarez I.C, Romero-Ibarra h. pfeiffer h. Balmori-Ramirez C. Gomez-Yanez Department of MetaUurgical and Materials Engineering National Polytechnic Institute ESIQIE-IPN UPALM Campus Instituto Politecnico NacionalAvenue 07738 Mexico City Mexico Materials Research Institute Morelia Campus National Autonomous University of Mexico Old Pdtzcuaro road 8701 58190 Morelia Michoacdn Mexico Department of Chemistry Metropolitan Autonomous University Iztapalapa Campus San Rafael Atlixco Avenue 186 09340 Mexico City Mexico Materials Research Institute National Autonomous University of Mexico Cd Universitaria Campus 04510 Mexico City Mexico

A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors. Ceramic powders were obtained under hydrothermal conditions of autogenous pressure in the presence of a nonionic surfactant. The production of pure and well-crystallized Li2 SiO3 using very short reaction times at low temperatures was shown by X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption analyses. Synthesized Li2SiO3 particles were nanocrystalline and exhibited different morphologies and specific surface areas depending on the synthesis conditions. Additionally, the capability of selected Li2SiO3 samples to absorb h20 and CO2 was evaluated via thermogravimet- ric analyses by varying the temperature, carrier gas, and water vapor concentration. Li2SiO3 particles exhibited interesting textural and morphological characteristics that make them suitable for use as a CO2 absorbent and which suggest that they also have the potential to be used in other applications.

关键词： CO2 capture Lithium metasilicate hydrothermal synthesis Thermal analysis

Modeling and simulation of recurrent phenotypic and genomic selections in plant breeding under the presence of epistasis

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The Crop Journal 2020年第5期8卷 866-877页

作者： Mohsin Ali Luyan Zhang Ian DeLacy Vivi Arief Mark Dieters wolfgang h.pfeiffer Jiankang wang huihui Li National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China School of Agriculture and Food Sciences The University of QueenslandBrisbaneQLD 4072Australia harvestPlus Challenge Programme c/o International Food Policy Research Institute(IFPRI)1201 Eye StNWWashingtonDC 20005USA

Recurrent selection is an important breeding method for population improvement and selecting elite inbreds or fixed lines from the improved ***,a computer simulation tool called QuMARS has been developed,which allows the simulation and optimization of various recurrent selection *** major objective in this study was to use the QuMARS tool to compare phenotypic recurrent,marker-assisted recurrent,and genomic selections(abbreviated respectively as PS,MARS and GS)for both short-and long-termbreeding ***,twomarker selection models were considered,i.e.,stepwise(Rstep)and forward regressions(Forward).For GS,three prediction models were considered,i.e.,genomic best linear unbiased predictors(GBLUP),ridge regression(Ridge),and regression by Moore-Penrose general inverse(InverseMP).To generate genotypes and phenotypes for a given individual during simulation,one additive and two epistasis genetic models were considered with three levels of *** demonstrated that selection responses from GBLUP-based GS and MARS(Forward)were consistently greater than those from PS under the additive model,particularly in early selection *** contrast,selection response from PS was consistently superior over MARS and GS under epistatic *** the two epistasis models,total genetic variance and the additive variance component were increased in some cases after *** simulation,we concluded that GS and PS were effective recurrent selection methods for improved breeding of targeted traits controlled by additive and epistatic quantitative trait loci(QTL).QuMARS provides an opportunity for breeders to compare,optimize and integrate new technology into their conventional breeding programs.

关键词： breeding elite additive

Fluoride ions adsorption from water by CaCO_(3)enhanced Mn-Fe mixed metal oxides

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Frontiers of Chemical Science and Engineering 2023年第2期17卷 236-248页

作者： Xinyuan wang heriberto pfeiffer Jiangjiang wei Jinyu wang Jinli Zhang School of Chemistry and Chemical Engineering/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi UniversityShihezi 832003China Institute of Materials National Autonomous University of MexicoMexico City 04510Mexico School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China

Novel CaCO_(3)-enhanced Mn-Fe mixed metal oxides(CMFC)were successfully prepared for the first time by a simple-green hydrothermal strategy without any surfactant or template combined with calcination *** oxides were then employed as an adsorbent for adsorptive removal of excess fluoride *** adsorbent was characterized by SEM,XPS,XRD,FTIR,and BET analysis *** adsorption property of CMFC toward fluoride ion was analyzed by batch *** fact,CMFC exhibited adsorption capacity of 227.3 mg∙g^(-1)toward fluoride *** showed that ion exchange,electrostatic attraction and chemical adsorption were the main mechanism for the adhesion of large amount of fluoride ion on the CMFC surface,and the high adsorption capacity responded to the low ph of the adsorption *** the fluoride ion concentration was increased from 20 to 200 mg∙L^(-1),Langmuir model was more in line with experimental *** change of fluoride ion adsorption with respect to time was accurately described by pseudosecond-order *** five cycles of use,the adsorbent still maintains a performance of 70.6%of efficiency,compared to the fresh ***,this material may act as a potential candidate for adsorbent with broad range of application prospects.

关键词： mesoporous materials metal oxides fluoride ion adsorption mechanism

Effects of longwall-induced stress and deformation on the stability and mechanical integrity of shale gas wells drilled through a longwall abutment pillar

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International Journal of Mining Science and Technology 2017年第1期27卷 115-120页

作者： Daniel w.h.Su National Institute for Occupational Safety and health Bruceton 15236PAUSA

This paper presents the results of a comprehensive study conducted by CONSOL Energy, Marcellus Shale Coalition, and Pennsylvania Coal Association to evaluate the effects of longwall-induced subsurface deformations on the mechanical integrity of shale gas wells drilled over a longwall abutment *** primary objective is to demonstrate that a properly constructed gas well in a standard longwall abutment pillar can maintain mechanical integrity during and after mining operations. A study site was selected over a southwestern Pennsylvania coal mine, which extracts 457-m-wide longwall faces under about 183 m of cover. Four test wells and four monitoring wells were drilled and installed over a 38-m by84-m centers abutment pillar. In addition to the test wells and monitoring wells, surface subsidence measurements and underground coal pillar pressure measurements were conducted as the 457-m-wide longwall panels on the south and north sides of the abutment pillar were mined by. To evaluate the resulting coal protection casing profile and lateral displacement, three separate 60-arm caliper surveys were conducted. This research represents a very important step and initiative to utilize the knowledge and science obtained from mining research to improve miner and public safety as well as the safety and health of the oil and gas industries.

关键词： Gas well Casing Abutment pillar Stability Safety and health Instrumentation Numerical simulation

Shortening the Duration of heat Treatment in the Lower Bainitic Range

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材料热处理学报 2004年第5期25卷 555-560页

作者： h. Vetters h.-w. Zoch Foundation Institute for Materials Science Bremen GermanyFoundation Institute for Materials Science Bremen Germany

In many cases an isothermal treatment of throughhardening bearing grades in the lower bainitic range allows to adjust the mechanical properties of machine components to the later application, similar to those of martensitic hardening. The achieved microstructure contains only a negligible amount of retained austenite, so a dimensional change of components during application can be reduced. One disadvantage of the isothermal bainitic treatment in salt bath is that the duration of the treatment is much longer than that of the martensitic hardening and this causes higher costs. Therefore it would be desirable to be able to shorten the transformation duration in the lower bainitic range. The aim of the present work is to determine the parameters, by which the process could be greatly shortened in comparison with the conventional transformation process in the lower bainitic range. Therefore the bainitic transformation behavior of the steel 100 Cr6 (SAE 52100) and the relevant influence factors were investigated by means of dilatometry, in which the heat treatments were carried out with different process variants including pre-quenching or post-quenching. The amount of retained austenite in the microstructure and the hardness of the steel after the shortened heat treatments were measured. Finally the possibility to use these processes in industrial production is discussed.

关键词：贝氏体轴承钢膨胀测定法热处理

MOLECULAR DYNAMICS SIMULATION OF STRUCTURE STABILITY OF SILVER NANOCLUSTERS

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 209-214页

作者： w.h. Qi School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 China School of Materials Science and Engineering Central South University Changsha 410083 China

The structures of Ag clusters with sizes n=13 to 1157 are studied by tight binding molecular dynamics simulation. It is found that the stable structures of Ag clusters follow the sequence amorphous-crystalline-amorphous-crystalline with the cluster size increasing from 13 to 1157. Furthermore, all the shells of Ag clusters are different from the structure of the corresponding bulk Ag.

关键词： structure stability molecular dynamics silver nanoclusters

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： h w A Riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Structural evolution and reaction mechanism of lithium nickelate(LiNiO_(2))during the carbonation reaction

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Journal of Materiomics 2018年第1期4卷 56-61页

作者： Daniela Gonzalez-Varela Brenda Alcantar-Vazquez heriberto pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autonoma de MexicoCircuito exterior s/nCUDel.CoyoacanCP 04510Ciudad de MexicoMexico Instituto de Ingenieria Coordinacion de Ingeniería AmbientalUniversidad Nacional Autonoma de MexicoCircuito Escolar s/nCUDel.CoyoacanCP 04510Ciudad de MexicoMexico

Lithium nickelate(LiNiO_(2))was synthesized using the lithium excess method,and then characterized by X-ray diffraction,scanning electron microscopy and N_(2) ***,differential thermal and thermogravimetric analyses were performed in CO_(2)presence,at high *** show that LiNiO_(2)is able to react with CO_(2)through a complex structural evolution process,where lithium atoms are released to produce Li_(2)CO_(3),while some nickel atoms are rearranged on different Li_(1-x)Ni_(1+x)O_(2)crystalline ***_(2)-CO_(2)reaction kinetic parameters were determined assuming a first-order reaction,where kinetic constants tended to increase as a function of ***,kinetic constant values did not follow a linear *** atypical behavior was attributed to LiNiO_(2)sintering and crystalline evolution performed as a function of temperature.

关键词： Lithium nickelate CO_(2)chemisorption Lithium diffusion coefficient Phase transition

Microstructure change in Fe-based metallic glass and nanocrystalline alloy induced by liquid nitrogen treatment

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Journal of Materials Science & Technology 2021年第10期69卷 1-6页

作者： M.C.Ri D.w.Ding Y.h.Sun w.h.wang Institute of Physics Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China

The effects of acyclic liquid nitrogen(LN)treatment in a temperature range of-196℃to 50℃on the thermal and magnetic stability of Fe78Si9B13 and Fe73.5Si13.5B9Nb3Cu1 glassy ribbons have been *** intrinsic heterogeneities of the metallic glasses can be activated through cryogenic thermal cycling,making irreversible structural changes after the treatment and inducing rejuvenation to the *** microstructural changes of both Fe-based metallic glass(MG)and nanocrystalline alloy induced by LN treatment were *** experimental results show that the LN treatment could effectively rejuvenate the Fe-Si-B MGs and change their thermomechanical and magnetic *** on the partially-crystallinity and well-known magnetic constants,the increase of the energy at the order of 10m J/g and magnetic domain wall movement and rotation at the order of 5-6μm and 0.5°-0.8°are found for FINEMET-type amorphous alloy after LN *** is also found that LN treatment can contribute a little stored energy to the magnetic domain wall movement and magnetic domain rotation.

关键词： Metallic glasses Cryogenic thermal treatment Soft magnetic materials Rejuvenation Stored energy Domain wall