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"In-situ Recycling" :Monolithic Ladle Repair with Shotcreting

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China's Refractories 2015年第1期24卷 44-50页

作者： Christoph WHRMEYER christopher parr Fabien SIMONIN Bin LI Susan Li Simon GAO Magali SZEPIZDYN Jim FARRELL Scott KNIGHTON Kemeos S.A. Paris-Neuilly92521 France & Beijing 100027China Blastcrete Equipment Company

The service life of refractories in ladle walls is limited by corrosion,abrasion,thermal shock and structural spalling mechanisms. When the ladle is lined with bricks they typically need to be completely removed after a certain number of heats to be replaced by new bricks of the same size as the original bricks. Not so for monolithic ladle linings. At the end of their service life the remains of the castable can almost completely be recycled as they can in fact stay in place. Only the worn-out part of the lining has to be replaced by a new castable. 20%-50% of the initial ladle lining can be recycled ＂insitu＂. The installation can efficiently be done by shotcreting technics. But it requires a castable that resists slag penetration very well. Castables based on a calcium magnesium aluminate bond provide the required penetration resistance. Pumping and shotcreting is very well adapted for repairs of blast furnace shafts,torpedo cars,hot metal and steel ladle linings[1]. However,very little is published about how a good pumping and shotcreting performance can be achieved when the installation has to be done under extreme weather conditions. At high ambient temperature the challenge is to ensure a good pumping result without early castable stiffening. Blockage of the pump would be the consequence. At low ambient temperature the difficulty is to de-activate the highly efficient deflocculant fast enough with a gelling agent added intothe wet mix at the nozzle to prevent the gunned material slipping off the wall. This paper studies strategies how to achieve good installed properties even at extreme ambient temperatures. The interactions between deflocculants,retarders,gelling agents,and calcium magnesium aluminate binder as a function of temperature are studied for an alumina- spinel ladle castable. Beside a new gelling agent for this castable type also a special stabilizer to reduce the temperature sensitivity has been investigated. It will be highlighted how the use of t

关键词： steel ladle slag penetration alumina spinel castable shotcreting recycling calcium magnesium aluminate gelling agent

氧化铝微粉与减水剂对刚玉质浇注料施工性能的影响

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耐火材料 2009年第6期43卷 445-448页

作者：李文平刘学新李斌 christopher parr 凯诺斯铝酸盐(中国)技术有限公司北京100027

研究了减水剂(包括六偏磷酸钠和萘系、三聚氰胺类及聚羧酸盐类3类减水剂)、氧化铝微粉(包括烧结氧化铝微粉和活性氧化铝微粉)对纯铝酸钙水泥结合刚玉质浇注料的流动性能和力学性能的影响。结果表明:1)氧化铝微粉的平均粒度对浇注料的流... 详细信息

研究了减水剂(包括六偏磷酸钠和萘系、三聚氰胺类及聚羧酸盐类3类减水剂)、氧化铝微粉(包括烧结氧化铝微粉和活性氧化铝微粉)对纯铝酸钙水泥结合刚玉质浇注料的流动性能和力学性能的影响。结果表明:1)氧化铝微粉的平均粒度对浇注料的流动度有较大的影响,在一定范围内,粒度越粗,浇注料的初始流动性越小,可工作时间越短。2)氧化铝微粉中可溶性碱性氧化物的含量对浇注料的施工性能和可工作时间有一定的影响。3)减水剂既影响浇注料的需水性,还影响浇注料的强度发展,必要时需引入缓凝剂或者促硬剂进行调节。4)综合比较萘系、三聚氰胺类及聚羧酸盐类3类减水剂,以聚羧酸盐类减水剂的减水效果较好。

关键词：氧化铝微粉减水剂聚羧酸盐类刚玉质浇注料

铝酸盐水泥结合耐火浇注料表面损毁的原因分析及对策

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耐火材料 2009年第5期43卷 391-392页

作者：李斌孙加林刘学新 christopher parr 北京科技大学材料科学与工程学院北京100083 凯诺斯铝酸盐技术有限公司北京100027

在铝酸盐水泥结合耐火浇注料中,有相当一部分产品在施工后的养护过程中,坯体表面容易发生一些损坏现象,轻则造成表面粉化剥落,重则直接导致坯体失去结合强度而粉化坍塌.

关键词：耐火浇注料铝酸盐水泥体表面损毁原因损坏现象结合强度粉化

低水泥浇注料中纯铝酸钙水泥和SiO2微粉的“老化”试验

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耐火材料 2009年第2期43卷 103-105页

作者：李斌陈俊红孙加林 christopher parr 刘学新北京科技大学材料科学与工程学院北京100083 凯诺斯铝酸盐技术有限公司北京100027

为了探讨纯铝酸钙水泥结合的低水泥浇注料"老化"的原因和影响因素,将SiO2微粉以及不同粒度、不同物相组成(CA相含量)、不同新鲜程度的纯铝酸钙水泥在温度为(20±1)℃、相对湿度>75%的潮湿环境中摊成厚度为2.5 cm左右的料层,放置一定时间... 详细信息

为了探讨纯铝酸钙水泥结合的低水泥浇注料"老化"的原因和影响因素,将SiO2微粉以及不同粒度、不同物相组成(CA相含量)、不同新鲜程度的纯铝酸钙水泥在温度为(20±1)℃、相对湿度>75%的潮湿环境中摊成厚度为2.5 cm左右的料层,放置一定时间(分别为0、3、7、14、28 d)使其老化,然后分别将它们与特级矾土(≤5、≤0.088 mm)、磷酸盐分散剂和减水剂等其他原料一起配制成浇注料,通过测定浇注料的可工作时间、初始流动性和早期(6 h)养护强度,来表征这些原料的老化速度。结果表明:(1)纯铝酸钙水泥的CA含量和细度越高,其老化速度越快。(2)"新鲜"的铝酸盐水泥比存放一段时间后的水泥的老化速度更快。(3)SiO2微粉的老化会导致浇注料的流动性变差,可工作时间变短。

关键词：低水泥浇注料纯铝酸钙水泥 SiO2 微粉老化

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： christopher J.O’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Protecting miners from coal bursts during development above historic mine workings in Harlan County,KY

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International Journal of Mining Science and Technology 2021年第1期31卷 111-116页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15236USA

In order to reach a large,untapped reserve of high-quality coal,D8 Cloverlick Mine proposed to mine a corridor nearly 600 m deep beneath the Benham Spur of Black Mountain,Kentucky’s highest peak.D8 Cloverlick Mine was extracting the Owl seam,but the corridor’s route lay approximately 20 m above century-old mine workings in the C–(Darby)*** to the concern,three serious coal bursts had recently occurred in nearby Owl seam *** of the old workings seemed to indicate that the underlying C–seam had been fully ***,two of the coal bursts had occurred above areas where the C–Seam was also shown as mined *** Safety and Health Administration(MSHA)Technical Support therefore investigated the records of past mining to better understand the old mine *** conditions observed in current Owl seam workings were also compared with the maps of the old C–seam *** study concluded that the presence of hazardous underlying remnants could not be ruled *** mitigate the burst risk,D8 Cloverlick Mine adopted a strategy of stress probe drilling.A self-propelled coal drill was used to auger 11.5-m-long,small diameter holes in advance of *** each hole was drilled,the cuttings were measured to detect the presence of highly stressed *** the crossing was successfully completed without incident.

关键词： Coal bursts Underground mining Room-and-pillar Destressing

An updated empirical model for ground control in *** coal mines

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International Journal of Mining Science and Technology 2021年第2期31卷 163-174页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15217USA

Multiple seam interactions are a major source of ground instability in several *** methods are well suited for this problem,because while the mechanics multiple seam interactions are very complex and poorly understood,many mining case histories are available for *** study makes use of an updated database that includes 356 multiseam case histories,including 67 unsuccessful *** paper describes in detail the process used to design the study,collect the data,conduct the statistical analysis,and develop the quantitative *** model can be used for mine planning in multiple seam situations,and has been made available as a module within the Analysis of Coal Pillar Stability(ACPS)computer program.

关键词： Underground Coal Multiseam Ground control Pillar design Empirical

Coal bursts that occur during development: A rock mechanics enigma

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International Journal of Mining Science and Technology 2018年第1期28卷 35-42页

作者： christopher Mark Safety and Health Administration Pittsburgh 15236USA

Coal bursts are typically associated with highly stressed *** bursts occur during retreat mining(longwall mining or pillar recovery) in highly stressed locations like the tailgate corner of the longwall *** are associated with multiple seam ***, a small but significant percentage of coal bursts have occurred during development or in outby locations unaffected by active *** development bursts have been relatively small, but some have been highly *** theory of coal bursts can be complete if it does not account for this type of *** paper focusses on the development mining coal burst experience in the US, putting it into the context of the entire US coal burst *** first documented development coal burst occurred almost exactly 100 years ago during slope drivage at the Sunnyside Mine in *** subsequently had a long history of bursts, mainly during retreat mining but also during *** Colorado mines have also experienced multiple development ***, but by no means all, of the development bursts in these western US coalfields have been associated with known *** the Central Appalachian coalfields, most development bursts have occurred in multiple seam *** some of these cases, however, there was no retreat mining in either *** paper closes with some lessons from this history, with implications for preventing such events in the future.

关键词： Coal Underground Ground control Bursts Multiple seam

Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

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Current Zoology 2011年第2期57卷 187-196页

作者： christopher James CLARK Peabody Museum of Natural History Yale University PO Box 208106 New Haven CT 06511 USA Museum of Vertebrate Zoology University of California- Berkeley Berkeley CA USA

Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone （hfl）, a low frequency tone （lft）, and atonal sound pulses （asp）, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices （tail-feathers） of wild males impaired production of the lft and asp but not the hfl or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds sitlfilar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism .

关键词： Calliope Hummingbird Courtship Multicomponent Signal Sonation Wind Tunnel