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酸性气体回注、硫磺的储存及硫能源

硫酸工业 2004年第6期 13-18页

作者： p.d.clark p.M.dAVIS N.I.dOWLING 宋佥阿尔伯塔硫研究有限公司

论述酸性气体回注、硫磺的储存以及硫磺在能量生产中的应用。对北美,尤其是加拿大西部正在进行的酸性气体回注项目进行分析,结果表明,将H2S回注入耗竭的矿井已达到相当的规模,并开始影响该地区的硫磺供应。在世界其它地区,只要能够找到... 详细信息

论述酸性气体回注、硫磺的储存以及硫磺在能量生产中的应用。对北美,尤其是加拿大西部正在进行的酸性气体回注项目进行分析,结果表明,将H2S回注入耗竭的矿井已达到相当的规模,并开始影响该地区的硫磺供应。在世界其它地区,只要能够找到合适的矿井,实施更大规模的回注计划似乎已不存在技术障碍。只要在项目的生命周期内进行适当地规划和维护,传统的地面硫块储存是一项可行而安全的技术。硫磺的地下储存仍然是现场中试研究的一个焦点,对于长期储存可能是一项非常有用的技术。提出了一些利用H2S和硫磺生产能量的方案,将H2S通过"绿色"技术进行燃烧和可再生循环。其中两种方案利用了太阳能,一种是间接通过生物质的积累,另一种则是直接使用太阳能收集器。

关键词：酸性气体回注硫磺储存硫能源

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液硫脱气与克劳斯尾气处理

硫酸工业 2012年第4期 10-13页

作者： p.d.clark M.A.SHIELdS N.I.dOWLING 瑾阿尔伯塔硫研究有限公司卡尔加里大学

采用三氧化二铝或二氧化硅固体催化剂进行的最新实验室研究表明,H_2S_χ先在催化剂表面的碱性位分解为H_2S,然后被吹扫气从液硫中驱除出去。由于H_2S从气相返回液相的传质是一个有限的过程,从理论上讲,这预示着可利用克劳斯尾气作为吹... 详细信息

采用三氧化二铝或二氧化硅固体催化剂进行的最新实验室研究表明,H_2S_χ先在催化剂表面的碱性位分解为H_2S,然后被吹扫气从液硫中驱除出去。由于H_2S从气相返回液相的传质是一个有限的过程,从理论上讲,这预示着可利用克劳斯尾气作为吹扫气。试验还揭示,在涂有三氧化二铝的堇青石上,脱气期间尾气中约60%的H_2S和SO_2,转化为元素硫。这预示着(例如)可在硫冷凝器管内衬入涂有三氧化二铝的堇青石管,以在脱气的同时提高总转化率。

关键词：克劳斯工艺液硫脱气尾气吹扫气

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脱除SO_2并回收硫磺的冶炼烟气处理工艺

硫酸工业 2006年第3期 40-45页

作者： L.Micucci A.danieletto p.d.clark N.I.dowling 胡小云 Siirtec Nigi公司 Alberta硫研究有限责任公司

介绍用甲烷(天然气)直接还原技术使冶炼烟气中SO2生成元素硫的工艺研究。SO2直接还原法分2 步:在高温下用甲烷将部分SO2还原成S和H2S,然后未反应的SO2和H2S发生Claus转化反应生成S。研究发现, 在工业装置中还原反应器宜采用分批甲烷法进... 详细信息

介绍用甲烷(天然气)直接还原技术使冶炼烟气中SO2生成元素硫的工艺研究。SO2直接还原法分2 步:在高温下用甲烷将部分SO2还原成S和H2S,然后未反应的SO2和H2S发生Claus转化反应生成S。研究发现, 在工业装置中还原反应器宜采用分批甲烷法进料,以避免烟灰的生成;另需严格控制各种物料的相对比例,以确保位于Claus转化系列的硫冷凝器排出的尾气中的H2S／SO2为2,从而优化工艺性能。另外试验发现,在不同的停留时间下,SO2转化率与反应温度的关系曲线变化趋势是相反的,因此必须根据具体的现场条件选择停留时间。Siirtec Nigi公司和Albera硫研究有限责任公司联合开发了一种CH4／SO2还原／Claus／HCRTM工艺,其总硫回收率可达到99％以上。试验确定了一组有价值的化学工程数据,可用于该工艺的工业装置设计。

关键词：冶炼烟气脱除SO2 回收硫磺试验研究工业装置

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克劳斯催化过程的实际情况

硫酸工业 2006年第4期 21-28页

作者： p.d.clark[加拿大] N.I.dowling[加拿大] M.Huang[加拿大] 瑾（译）阿尔伯塔硫研究有限公司加拿大不详

结合现场操作情况,考查了在克劳斯催化剂上H2S／SO2转化反应的基本化学原理。结果表明,在缺氧条件下硫酸盐在催化剂表面的形成是克劳斯催化过程中的一种基本情况,也是降低CS2转化率和导致催化剂因BTX降解而结垢的原因。结合催化剂表面... 详细信息

结合现场操作情况,考查了在克劳斯催化剂上H2S／SO2转化反应的基本化学原理。结果表明,在缺氧条件下硫酸盐在催化剂表面的形成是克劳斯催化过程中的一种基本情况,也是降低CS2转化率和导致催化剂因BTX降解而结垢的原因。结合催化剂表面天然硫酸盐的生成,对更换催化剂和高比值浸润问题进行论述。最后考查了亚露点操作的催化剂设计问题。

关键词：克劳斯反应化学原理硫酸盐化 BTX 亚露点催化剂

利用硫化氢的部分氧化生产氢、硫磺、乙烯和丙烯

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硫酸工业 2004年第4期 1-8页

作者： p.d.clark N.I.dOWLING M.HUANG S.LUI X.LONG 瑾阿尔伯塔硫研究有限公司

阐述用硫化氢生产氢、乙烯、丙烯等新技术的基本原理,由于其中涉及元素硫的生产,故可将其作为硫回收总体方案中的一部分。这些工艺的主要优点是,生产每种终端产品时不必输入外部能量,因此燃料消耗大大低于目前采用的氢和烯烃生产工艺。... 详细信息

阐述用硫化氢生产氢、乙烯、丙烯等新技术的基本原理,由于其中涉及元素硫的生产,故可将其作为硫回收总体方案中的一部分。这些工艺的主要优点是,生产每种终端产品时不必输入外部能量,因此燃料消耗大大低于目前采用的氢和烯烃生产工艺。此外,乙烯和丙烯的产率较高,选择性较好。这些技术的另一个重要方面是,在所谓的石油时代以后,由于可用生物质作为有机原料,并用硫磺作为循环方案的最初氧化剂,故它们是可持续的。

关键词：硫化氢硫回收部分氧化氢烯烃生产新技术

Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen p.Nutman clark R.L.Friend Vickie C.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;Rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing plate tectonics Suprasubduction Crustal evolution

Clinical gait analysis in older children with autism spectrum disorder

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Sports Medicine and Health Science 2024年第2期6卷 154-158页

作者： Xinye Wu d.clark dickin Laura Bassette Caroline Ashton He Wang School of Kinesiology Ball State UniversityMuncieINUSA department of Special Education Ball State UniversityMuncieINUSA

Individuals with autism spectrum disorder(ASd)often exhibit motor deficits that increase their risk of *** is a lack of understanding regarding gait biomechanics demonstrated by older children with *** purpose of the study was to determine differences in gait patterns between older children with ASd and typically developing *** children with ASd and 11 age-and gender-matched typically developing children were recruited for the *** walked on a force-instrumented treadmill at a constant speed(1.1 m/s-1.2 m/s)for five minutes(min).participants performed maximal voluntary contractions to assess their knee muscular *** between individuals with ASd and matched control participants were examined through paired t-tests with a significance level of p*** with ASd demonstrated a smaller knee extensor torque compared to controls(p=0.002).participants with ASd exhibited a shorter stride length(p=0.04),a greater cadence(p=0.03),and a higher variation in stride width(p=0.04)compared to control *** individuals with ASd experienced a greater braking ground reaction force(p=0.03)during loading *** results indicate older children with ASd develop a unique gait pattern signified by a reduced stride length,increased cadence,and an increase of variation in stride *** unique gait pattern may represent a movement strategy used by the individuals with ASd to compensate for the weakness associated with their knee extensor *** with ASd who demonstrate these unique gait deviations may face reduced postural stability and an increased risk of fall-related injuries.

关键词： Autism spectrum disorder Gait analysis Knee strength Gait development Older children

Robust Machine Learning Mapping of sEMG Signals to Future Actuator Commands in Biomechatronic devices

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Journal of Bionic Engineering 2024年第1期21卷 270-287页

作者： Ali Nasr Sydney Bell Rachel L.Whittaker clark R.dickerson John Mcphee Systems design Engineering University of WaterlooWaterloo N2L 3G1Canada Kinesiology and Health Sciences University of WaterlooWaterloo N2L3G3Canada

A machine learning model for regression of interrupted Surface Electromyography(sEMG)signals to future control-oriented signals(e.g.,robot’s joint angle and assistive torque)of an active biomechatronic device for high-level myoelectric-based hierarchical control is proposed.A Recurrent Neural Network(RNN)was trained using output data,initially obtained from offline optimization of the biomechatronic(human–robot)device and shifted by the prediction *** input of the RNN consisted of interrupted sEMG signals(to mimic signal disconnections)and previous kinematic signals of the assistive *** RNN with a 0.1-s prediction horizon could predict the control-oriented joint angle and assistive torque with 92%and 86.5%regression accuracy,respectively,for the test *** proposed approach permits a fast,predictive,and direct estimation of control-oriented signals instead of an iterative process that optimizes assistive torque in the inverse dynamic simulation of a multibody human–robot *** with these interrupted input signals significantly improves the regression accuracy in the case of sEMG signal *** Robust predictive Control-oriented Machine Learning(Robust-MuscleNET)model can support volitional high-level myoelectric-based control of biomechatronic devices,such as exoskeletons,prostheses,and assistive/resistive *** work should study the application to prosthesis control as well as the repeatability of the high-level controller with electrode *** low-level hierarchical controller that manages the human–robot interaction,the assistance/resistance strategy,and the actuator coordination should also be studied.

关键词： Myoelectric-based control-Surface electromyography Machine learning Multibody system dynamics Exoskeleton Bionic

Enantioselective iridium-catalyzed allylic substitution with a Reformatsky reagent: direct construction of β-stereogenic homoallylic esters

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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： debasis pal Kirana d.Veeranna Yuk Fai Wong p.Andrew Evans department of Chemistry Queen's University Xiangya School of pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent