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Advancing respirable coal mine dust source apportionment:a preliminary laboratory exploration of optical microscopy as a novel monitoring tool

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International Journal of Coal Science & Technology 2024年第2期11卷 222-233页

作者： Nestor santa Emily Sarver Department of Mining and Minerals Engineering Virginia TechBlacksburgVA 24061USA

Exposure to respirable coal mine dust(RCMD)can cause chronic and debilitating lung ***-time monitoring capabilities are sought which can enable a better understanding of dust components and *** many underground mines,RCMD includes three primary components which can be loosely associated with three major dust sources:coal dust from the coal seam itself,silicates from the surrounding rock strata,and carbonates from the inert‘rock dust’products that are applied to mitigate explosion hazards.A monitor which can reliably partition RCMD between these three components could thus allow source *** tracking silicates,specifically,could be valuable since the most serious health risks are typically associated with this component-particularly if abundant in crystalline *** a monitoring concept based on field microscopy,and following up on prior research using polarized light,the aim of the current study was to build and test a model to classify respirable-sized particles as either coal,silicates,or *** model development,composite dust samples were generated in the laboratory by successively depositing dust from high-purity materials onto a sticky transparent substrate,and imaging after each deposition event such that the identity of each particle was known a *** testing followed a similar approach,except that real geologic materials were used as the source for each dust *** showed that the model had an overall accuracy of 86.5%,indicating that a field-microscopy based moni-tor could support RCMD source apportionment and silicates tracking in some coal mines.

关键词： Polarized light microscopy Image processing Dust monitoring Respirable silica Coal mining

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Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science China Chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2.& CHEN Shaowei3 1. State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13002., China 2. Department of Chemistry, Tsinghua university, Beijing 100084, China 3. Department of Chemistry, university of {2.fornia, santa cruz, santa cruz, ca 95064, usa State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China Department of Chemistry Tsinghua University Beijing China Department of Chemistry University of California Santa Cruz Santa Cruz USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3-Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

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No apparent lock-in depth of the Laschamp geomagnetic excursion: Evidence from the Malan loess

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Science China Earth Sciences 2006年第9期49卷 960-967页

作者： ZHU Rixiang1, LIU Qingsong1,2. PAN Yongxin1, DENG Chenglong1, ZHANG Rui1 & WANG Xianfeng3 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution), Institute of Geology and Geophysics, Chi- nese Academy of Sciences, Beijing 10002., China 2. Institute of Geophysics and Planetary Geophysics, university of cali{2., santa cruz, ca 95064, usa 3. Department of Geology and Geophysics, university of Minnesota, Minneapolis, MN 55455, usa Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Institute of Geophysics and Planetary Geophysics University of California Santa Cruz USA Department of Geology and Geophysics University of Minnesota Minneapolis USA

The first-order chronological framework of the long-term Chinese loess/paleosol sequences was based mainly on magnetostratigraphy. However, there remain arguments on the lock-in ages of the major geomagnetic reversals. This study systematically compared the stratigraphic locations of the Laschamp excursion and Henrich events (H4 at～39 ka and H5 at～48 ka) recorded by the Luochuan loess profile in the central Chinese Loess Plateau. Results show that the Lascchamp excursion is bracketed well by these two cold events, and the corresponding estimated age is between about 41.7-43.7 ka, which is close to the widely accepted age of ～40-41 ka for the ***, our new results do not suggest apparent lock-in effects in the last glacial Malan loess.

关键词： Chinese loess, Laschamp excursion, Henrich event, lock-in depth.

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Rock magnetic studies on the hominoid-bearing sediments at Zhupeng, Yuanmou Basin, southwestern China and its paleoclimatic significance

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Science Bulletin 2005年第15期 119-126页

作者： YAO Haitao1, LIU Qingsong1,2. Lü Lianqing1, CHANG Zhigang1 & ZHU Rixiang1 1. Paleomagnetism Laboratory, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. Institute of Geophysics and Planetary Geophysics, university of cali-fornia, santa cruz,{2., usa

It has been proposed that paleoclimatic changes and tectonic events strongly affect hominoid evolution. The Zhupeng section at Yuanmou Basin, southwestern China, with the hominoid-bearing fluvial-lacustrine sediments, is an ideal natural laboratory to test this hypothesis. This study provided an integrated magnetic study, including low-fre- quency susceptibility, the anisotropy of magnetic susceptibil-ity, temperature-dependent susceptibility, hysteresis loops, isothermal remanent magnetization, and anhysteretic rema-nent magnetization, on samples from the Baozidongqing section at Zhupeng. Results show that the dominant mag-netic carrier is hematite, with minor amount of magnetite. Both the composition and concentration of magnetic miner-als strongly correlate with the lithostratigraphy. At least eight short-term events defined by higher concentrations of magnetite were identified. These short events reflect that the subtropical dry-hot climate is similar to today’s climate. Basing on the lithostratigraphic and rock magnetic results, we suggest that Yuanmou Basin was in a steady deposition environment from about 11 to 7 Ma, which is characterized by alternating of long-term torrid-humid climate and short-term dry-hot climate. Our study provides invaluable environment information for understanding the climate shift and the relationship between paleoenvironment and homi-noid evolution in southwestern China during late Miocene.

关键词： Yuanmou Basin hominoid late Miocene rock magnet-ism paleoclimate.

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Radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： cruz I.Velasco Valerio Di Giulio F.Javier García de Abajo ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain ICREA-Instituciócatalana de Recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involving macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupling between charged particles and extended objects could also trigger quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupling in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacting with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupling of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuring the vacuum temperature and nondestructively sensing the presence of distant objects.

关键词： temperature quantum macroscopic

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Gray Images of Constacyclic Codes over a Non-chain Extension of Z_(4)

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Algebra Colloquium 2024年第1期31卷 11-24页

作者： cruz Mohan Karthick Gowdhaman Durairajan Chinnapillai Jian Gao Department of Mathematics Bishop Heber CollegeTrichyTamil NaduIndia Presidency university BengaluruKarnatakaIndia School of Mathematics and Statistics Shandong University of Technology ZiboShandong 255000China

Let Z_(4) be the ring of integers modulo *** study the Λ-constacyclic and(θ,Λ)-cyclic codes over the non-chain ring R=Z_(4)[u,v]/for a unit Λ=1+2.+2. in *** define several Gray maps and find that the respective Gr... 详细信息

Let Z_(4) be the ring of integers modulo *** study the Λ-constacyclic and(θ,Λ)-cyclic codes over the non-chain ring R=Z_(4)[u,v]/2.=1,v^(2.=0,uv=vu=0>for a unit Λ=1+2.+2. in *** define several Gray maps and find that the respective Gray images of a quasi-cyclic code over Z_(4) are cyclic,quasi-cyclic or permutation equivalent to this *** an odd positive integer n,we determine the generator polynomials of cyclic and Λ-constacyclic codes of length n over ***,we prove that a(θ,Λ)-cyclic code of length n is a Λ-constacyclic code if n is odd,and a Λ-quasi-twisted code if n is even.A few examples are also incorporated,in which two parameters are new and one is best known to date.

关键词： non-chain ring linear code Ot-cyclic code Gray map (θ_(t),Λ)-cyclic code

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多措并举标本兼治有力有效做好基督教工作

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中国宗教 2024年第5期 33-34页

作者： 1.中共山东省委统战部 2.山东省民宗委中共山东省委统战部山东省民宗委

近年来,山东省结合实际,采取有力举措,扎实做好基督教工作,有效推进基督教中国化山东实践,全省基督教领域呈现出和谐稳定的良好局面。一、严格落实宗教工作责任制,着力构建齐抓共管的宗教事务管理格局山东严格落实各级各部门宗教工作责... 详细信息

近年来,山东省结合实际,采取有力举措,扎实做好基督教工作,有效推进基督教中国化山东实践,全省基督教领域呈现出和谐稳定的良好局面。一、严格落实宗教工作责任制,着力构建齐抓共管的宗教事务管理格局山东严格落实各级各部门宗教工作责任制,通过强化组织保障“小切口”,推动基层宗教事务管理“大文章”。一是压实主体责任。将宗教工作纳入各级党委重要议事日程,构建起各级党委齐抓共管的工作体制。

关键词：基督教中国化齐抓共管宗教事务管理主体责任工作责任制和谐稳定严格落实标本兼治

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Total synthesis of(+)-lentiginosine via a key Au catalysis

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Science China Chemistry 2010年第1期53卷 113-118页

作者： CUI Li & ZHANG LiMing Department of Chemistry & Biochemistry,university of cali{{2.,santa Barbara,ca 93106,usa Department of Chemistry & Biochemistry University of California Santa Barbara USA

Total syntheses of(+)-lentiginosine and its 8a-epimer using a gold-catalyzed oxidative cyclization as the key step were *** gold chemistry,reported previously in a 4+2.synthesis of piperidin-4-ones,tolerates functiona... 详细信息

关键词： gold total synthesis cyclization oxidation alkaloid

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永恒的丰碑：“大陈岛垦荒红色档案”建设侧记

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浙江档案 2024年第5期 10-11+16页

作者： 1.台州市档案馆 2.台州市椒江区档案馆台州市档案馆台州市椒江区档案馆

在台州市椒江区档案馆的特藏馆内，挂着一幅由团中央在1956年赠给温州青年志愿垦荒队的旗帜“建设伟大祖国的大陈岛”，这面旗帜承载着一件件珍贵的档案史料和一个个生动的历史场景，大陈岛激情燃烧的垦荒史、波澜壮阔的发展史，宛如画...

在台州市椒江区档案馆的特藏馆内，挂着一幅由团中央在1956年赠给温州青年志愿垦荒队的旗帜“建设伟大祖国的大陈岛”，这面旗帜承载着一件件珍贵的档案史料和一个个生动的历史场景，大陈岛激情燃烧的垦荒史、波澜壮阔的发展史，宛如画卷般展现在眼前。“大陈岛垦荒精神”是台州的城市精神，是这座城市发展生生不息的力量源泉。1956年到1960年，温州、台州两地467名青年陆续上岛支援建设，他们卷起裤管，咬紧牙关，用血和汗锻炼成了一个个生产能手，在荒岛上发展出种植业、畜牧业和海洋养殖业。一代垦荒人用青春和汗水孕育了“艰苦创业、奋发图强、无私奉献、开拓创新”

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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment

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Avian Research 2024年第1期15卷 55-59页

作者： Macarena castro Andrés De la cruz Nuria Martin-Sanjuan Alejandro Pérez-Hurtado Instituto Universitario de Investigacion Marina(INMAR) Campus de Excelencia Internacional del Mar(CEIMAR)Departamento de BiologíaUniversidad de CadizPuerto RealSpain Servicios centrales de Investigacion Salinas de la Esperanza Universidad de CadizPuerto RealSpain

Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal ***,supratidal habitats as saltpans could play a role in buffering human *** have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding *** it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they *** this hypothesis,we supplemented a restored saltpan in 2.19 and 2.2. with bivalve shells,expecting an increase in the number of breeding birds’ *** than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both *** best model for both species indicates that the presence of shells is the factor that most correlates with the location of *** probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little *** result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint.

关键词： Habitat management Nest site selection Saltpan restoration Shell supplementation Shorebirds

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