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无弹性物质参与的密封是未来的趋势

流程工业 2024年第4期 14-17页

作者： Harry Jost Anja Quattelbaum Matthias Dörr NEUMO gmbh+co.kg

即将实施的PFAS(全氟和多氟烷基化合物)禁令以及更严格的TA Luft(空气清洁技术标准)排放限值,是当前困扰着化工和生命科学行业从业者的两大热门话题。这使得管道连接如何能够实现安全密封并符合法规要求成为焦点问题。本文描述了制药、... 详细信息

即将实施的PFAS(全氟和多氟烷基化合物)禁令以及更严格的TA Luft(空气清洁技术标准)排放限值,是当前困扰着化工和生命科学行业从业者的两大热门话题。这使得管道连接如何能够实现安全密封并符合法规要求成为焦点问题。本文描述了制药、生物科技、食品和化工及氢能领域在这样的政策环境下所面临的问题,并给出了解决方案。此外,本文还特别介绍了不含弹性密封材料的管道连接件,并强调了无弹性物质参与的密封是未来的趋势。

关键词：连接件密封交叉污染

Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402,I0007页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China GRIREM Hi–Tech co. Ltd.Langfang065201China GRIREM Advanced Materials co. Ltd.Beijing100088China GRIMAT Engineering Institute co. Ltd.Beijing101407China

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most common mining *** high contents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A comprehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ *** paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and *** results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare *** samples have distinct areas of enrichment for ion-exchangeable rare earths or ***-exchangeable rare earths are primary concentrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micromorphology and particle size of the clay *** inorganic hydroxy aluminum concentration in Chongzuo samples decreases continuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the concentration in Longyan samples(110.55-171.27 mg/kg)is almost independence with sampling *** results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the consumption of leaching agent.

关键词： Weathered crust elution-deposited rare earth ore Sequential extraction Occurrence Aluminum Rare earth elements

High-efficiency co_(2) sequestration through direct aqueous carbonation of carbide slag: determination of carbonation reaction and optimization of operation parameters

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 157-167页

作者： Zhiqiang Wang Longpeng Cui Yanfang Liu Jili Hou Hongwei Li Liang Zou Fuxia Zhu Department of coal and Syngas conversion Sinopec Research Institute of Petroleum Processing Co.Ltd.Beijing 100083China

Under the dual-carbon target, co_(2) mineralization through solid wastes presents a mutually beneficial approach for permanent carbon emission reduction at a low material cost, while also enabling the resource utilization of these wastes. However, despite its potential, a comprehensive understanding about the effect of industrial solid waste properties and operating parameters on the carbonation process, and the mechanism of direct aqueous carbonation is still lacking. A series of experiments were conducted to compare the carbonation performance of fly ash, steel slag, and carbide slag. Subsequently, co_(2) mineralization by carbide slag was systematically studied under various operating parameters due to its high co_(2) sequestration capacity. Results showed the reactivity of CaO and Ca(OH)2 was higher than that of CaO·SiO_(2) and 2CaO·SiO_(2). Carbide slag demonstrated a sequestration capacity of 610.8 g co_(2)/kg and carbonation efficiency ζCa of 62.04% under the conditions of 65 ℃, 1.5 MPa initial co_(2) pressure, 15 mL/g liquid-to-solid ratio, and 200 r/min stirring speed. Moreover, the formation of carbonates was confirmed through XRD, SEM-EDS, TG, and FTIR. A mechanism analysis revealed that initially, the rate of the carbonation process was primarily controlled by the mass transfer of co_(2) in the gas–liquid interface. However, the rate-determining step gradually shifted to the mass transfer of Ca2+ in the solid–liquid interface as the reaction time increased. This study lays the foundation for the large-scale implementation of co_(2) sequestration through carbide slag carbonation.

关键词： Industrial by-products Direct aqueous carbonation co_(2)sequestration Mass transfer

High cerium content(Nd-Pr-Ce)_(2)Fe_(14)B melt-spun ribbons with high coercivity

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Journal of Rare Earths 2024年第4期42卷 690-695页

作者： Yujiang Zhong Junming Wang Zikai Yuan Ruijin Liu Minggang Zhu Zhe Liu Xin Chen Wei Li Zhaohui Guo Division of Functional Materials Central Iron and Steel Research InstituteBeijing100081China Ningbo Jinji Strong Magnetic Material co. Ltd.Ningbo315172China Jiangxi Jiangwu Rare Metal New Material co. Ltd.Nanchang330013China

The effects of wheel speeds on the magnetic properties and microstructures of[(Nd,Pr)_(1-x)Ce_(x)]-Fe-B meltspun ribbons were *** to melt-spun ribbons with low cerium(Ce)content(x=0.2),amorphous formation can be suppressed at high wheel speed in the ribbons with a relatively high Ce content(x=0.8),and with the increase of the wheel speed,the magnetic properties of the ribbons with high Ce content raise *** high wheel speed,the coercivity mechanism of melt-spun ribbons is mainly pinning field,and the high wheel speed introduces a large number of defects into the matrix as pinning ***,ribbons with high Ce content form a fine and uniform grain structure,so the grain boundary area enlarges,which further hinders the movement of domain *** combined effects of the above factors enable ribbons with high Ce content to have excellent magnetic properties(Hcj=0.977 T,Mr=64 m^(2) A/kg)at the wheel speed of 35 m/s.

关键词： Wheel speed Cecontent Microstructure Magnetic properties Rare earths

High Quality Fixture Quenching Fixture Types, Levels of Automation and Machine Types

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材料热处理学报 2004年第5期25卷 601-606页

作者： STRENG Th HEESS K MUELLER-LAESSIG G HEESS gmbh & co kg Lampertheim GermanyHEESS GmbH & Co KG Lampertheim GermanyHEESS GmbH & Co KG Lampertheim Germany

The paper shows, how the quality of workpieces to be heat treated can be improved by using the technology of fixture-quenching. Different fixture systems, like fixed mandrel, expanding mandrel and lamellar mandrel are described. In the next section there is a comparison between manual operation of hardening machines vs. automated lines. Since there are applications for each, manual and fully automated hardening systems, HEESS has not only focused to develop automated lines, but also refined manual operated hardening machines (SP-Series). These take advantage of the latest technology, like for example quick tool change and PLC-control with workpiece parameter database. An overview over different machine types is given.

关键词：淬火机模压淬火自动控制人工操作

Weight regain after intragastric balloon for pre-surgical weight loss

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2040-2046页

作者： Danielle Abbitt Kevin Choy Alexandra Kovar Teresa S Jones Krzysztof J Wikiel Edward L Jones Department of Surgery University of ColoradoAuroraCO 80045United States Department of Surgery Rocky Mountain Regional Veteran Affairs Medical CenterAuroraCO 80045United States

BACkgROUND Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related *** can place patients at increased risk of operative and postoperative *** intragastric balloon has been shown to aid in minor weight loss,however its weight recidivism in patients requiring short interval weight loss has not been well *** To evaluate weight loss,ability to undergo successful elective surgery after intragastric balloon placement,and weight management after balloon *** This study is a retrospective review of patients in a single academic institution undergoing intragastric balloon placement from 2019-2023 to aid in weight loss prior to undergoing elective *** outcomes including weight loss,duration of balloon placement,successful elective surgery,weight regain postballoon and post-procedure complications were *** criteria included those with balloon in place at time of *** Thirty-three patients completed intragastric balloon therapy from 2019-2023 as a bridge to elective *** patients were required to participate in a 12-month weight management program to be eligible for balloon *** surgeries included incisional hernia repair,umbilical hernia repair,inguinal hernia repair,and knee and hip *** average age at placement was 53 years±11 years,majority(91%)were *** average duration of intragastric balloon therapy was 186 days±41 *** average weight loss was 14.0 kg±7.4 kg and with an average percent excess body weight loss of 30.0%(7.9%-73.6%).Over half of the patients(52.0%)achieved the goal of 30-50 lbs(14-22 kg)weight ***-one patients(64%)underwent their intended elective surgery,2 patients(6%)deferred surgery due to symptom relief with weight loss ***-one of the patients(64%)have documented weights in 3 months after balloon removal,in these patients the majority(76%)gained weight after balloon *** pat

关键词： Intragastric balloon Weight loss Obesity Bariatric Body mass index

Routing through open spaces-A performance comparison of algorithms

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Geo-Spatial Information Science 2018年第3期21卷 247-256页

作者： Stefan Hahmann Jakob Miksch Bernd Resch Johannes Lauer Alexander Zipf GIScience Research Group Institute of GeographyHeidelberg UniversityHeidelbergGermany Fraunhofer IVI Fraunhofer Institute for Transportation and Infrastructure SystemsDresdenGermany Department of Geoinformatics-Z_GIS University of SalzburgAustria Center for Geographic Analysis Harvard UniversityCambridgeMAUSA here gmbh&co kg Schwalbach am TaunusGermany

Finding the shortest path through open spaces is a well-known challenge for pedestrian routing engines.A common solution is routing on the open space boundary,which causes in most cases an unnecessarily long route.A possible alternative is to create a subgraph within the open *** paper assesses this approach and investigates its implications for routing engines.A number of algorithms(Grid,Spider-Grid,Visibility,Delaunay,Voronoi,Skeleton)have been evaluated by four different criteria:(i)Number of additional created graph edges,(ii)additional graph creation time,(iii)route computation time,(iv)routing *** show that each algorithm has advantages and disadvantages depending on the use *** identify the algorithms Visibility with a reduced number of edges in the subgraph and Spider-Grid with a large grid size to be a good compromise in many scenarios.

关键词： OpenStreetMap routing open space navigation pedestrian polygon

Ballistic tests on hot-rolled Ti-6Al-4V plates:Experiments and numerical approaches

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Defence Technology（防务技术） 2023年第8期26卷 39-53页

作者： Alexander Janda Benjamin James Ralph Yael Demarty Marcel Sorger Stefan Ebenbauer Aude Prestl Ingo Siller Martin Stockinger Helmut Clemens Department of Materials Science Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria Department Product Engineering Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria French-German Research Institute of Saint-Louis 5 Rue du General Cassagnou68300 Saint-LouisFrance voestalpine BOEHLER Bleche gmbh&co kg Boehler-Gasse 18680MürzzuschlagAustria

Superior ballistic performance and the lightweight character of Ti alloys are considered as main reasons for their use in armour applications against a broad spectrum of ballistic threats,***,fragment or blast *** dynamic loading caused by typical penetrators is characterized by high strain rates,only specific test methods allow a closer investigation of the respective material *** the present study,quasi-static and dynamic compression tests as well as ballistic tests were conducted on a twophase a+βalloy Ti-6Al-4V(in m%)manufactured by ***-deformation heat treatments,influencing microstructure and mechanical properties were applied in order to compare three different microstructural configurations:as-rolled,mill-annealed and ***,on the one hand,ballistic tests were employed for the determination of the ballistic limit velocity v_(50),compression tests,on the other hand,delivered essential input parameters for the application of the Johnson-cook constitutive model in a finite element simulation of the impact *** comparison of experimental results to simulation results was supplemented by means of microstructural characterization of tested samples with the focus set on the prevalently observed deformation and damage mechanisms,as for example adiabatic shearing.

关键词： Ti-6Al-4V Ballistic performance Split Hopkinson pressure bar FE simulation Adiabatic shear bands Intermetallic phase

On the Preparation of Low-Temperature-Rise and Low-Shrinkage concrete Based on Phosphorus Slag

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Fluid Dynamics & Materials Processing 2024年第4期20卷 803-814页

作者： Jianlong Jin Jingjing Ding Long Xiong Ming Bao Peng Zeng China construction Ready Mixed concrete co. Ltd.Wuhan430000China

The effects of different contents of a MgO expansive agent and phosphorus slag on the mechanical properties,shrinkage behavior,and the heat of hydration of concrete were *** slump flow,setting time,dry shrinkage,and hydration heat were used as sensitive parameters to assess the response of the considered *** shown by the results,in general,with an increase in the phosphorus slag content,the hydration heat of concrete decreases for all ages,but the early strength displays a downward trend and the dry shrinkage rate *** 90-d strength and dry shrinkage of concrete could be improved with a phosphorus residue content between 0%-20%,with the best performances in terms of mechanical properties and shrinkage characteristics being achieved for a content of 20 kg/m^(3).On the basis of these results,it can be concluded that appropriate amounts of phosphorus slag and MgO expansive agent can be used to improve the compressive strength of concrete in the later stage by reducing the hydration heat and dry shrinkage rate,respectively.

关键词： Phosphorus slag MgO expansion agent mass concrete hydration heat