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Density Functional Theory Study on the Adsorption of Dioxygen on Small Pt-Pd Clusters

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Chinese Journal of Structural Chemistry 2007年第1期26卷 63-78页

作者：李钠官文佳王艳丽马琳孙仁安孙公权 School of Chemistry and Chemical Engineering Liaoning Normal University Direct Alcohol fuel Cell Laboratory Dalian Institute of Chemical PhysicsThe Chinese Academy of Sciences

The electronic and physical properties of PtmPdn （m＋n≤5） metal clusters and their interactions with dioxygen have been studied by using hybrid density functional B3LYP method. The total energies, atomization energies, vibration frequencies, and charge distributions were reported. The Pt-Pt bridge site modified by Pd atoms was found to be the most active site for the dissociation of dioxygen, which was mainly due to the change of electronic structures of the Pt atoms in bimetallic Pt-Pd clusters.

关键词： clusters bridge site charge transfer density functional theory method

The impact of crystal defects towards oxide semiconductor photoanode for photoelectrochemical water splitting

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Frontiers of physics 2019年第5期14卷 37-61页

作者： Qi-Tao Liu De-Yu Liu Jian-Ming Li Yong-Bo Kuang Ningbo institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Nano Science and Technology institute University of Science and Technology of ChinaSuzhou 215123China Petroleum Geology research and Laboratory Center Research Institute of Petroleum Exploration & Development (RIPED)PetroChinaBeijing 100083China

Photoelectrochemical (PEC) water oxidation for sustainable clean energy and fuel production is a potential solution to the demands of organic pollutant removal and growing energy *** of high performance photoanodes,which is a key component in the system,is one of the central topics in the *** crystal defect is an old concept but fruiting new understanding witli promotive impact to the development of high performance *** this review,we elucidated the typical defects involved in the photoanode with the position where they play the roles in the structure and how the properties of photoanode are *** addition,we summarized the feasible protocols to maximize the pros but reduce the cons brought by having defects to the photoanode performance based on recent most prominent researcli advancements in the ***,we briefly sketched the future perspective with the challenges of this topic when in the scenario of possible developments into practical applications.

关键词： photoanode defect engineering oxide scinicoiuluctor water splitting charge transfer

Mechanical behaviors of deep pillar sandwiched between strong and weak layers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1111-1126页

作者： Sahendra Ram Petr Waclawik Jan Nemcik Radovan Kukutsch Ashok Kumar Arun Kumar Singh Libin Gong Department of Mining Engineering National Institute of TechnologyRourkelaOdishaIndia institute of Geonics The Czech Academy of SciencesOstravaCzech Republic University of Wollongong WollongongAustralia CSIR-Central institute of Mining and fuel research DhanbadJharkhandIndia Department of Mining Engineering Indian Institute of Technology(Indian School of Mines)DhanbadJharkhandIndia

A variety of coal room and pillar mining methods have been efficiently practiced at depths of up to 500 m with least strata mechanics ***,for the first time,this method was trialled at depths of 850 e900 m in CSM mine of Czech *** rhomboid-shaped coal pillars with acute corners of 70,surrounded with 5.2 m wide and 3.5e4.5 m high mine roadways,were *** were developed in a staggered manner with their size variation in the Panel II from 83 m×25 m to 24 m×20 m(corner to corner)and Panel V from 35 m×30 m to 26 m×16 *** seam inclined at 12was affected by the unusual slippery slickenside roof bands and sometimes in the floor levels with high vertical stress below strong and massive sandstone *** order to ensure safety,pillars in both the panels were continuously monitored using various geotechnical instruments measuring the induced stresses,side spalling and roof *** panels suffered high amounts of mining induced stress and pillar failure with side-spalling up to 5 m from all *** fracturing of coal pillar sides was controlled by fully encapsulated steel *** induced stress kept increasing with the progress of development of pillars and *** installed in the pillar failed to monitor actual induced stress due to fracturing of coal mass around it which created an apprehension of pillar failure up to its core due to high vertical mining induced *** risk was reduced by carrying out scientific studies including the three-dimensional numerical models calibrated with data from the instrumented *** attempt has been made to study the behavior of coal pillars and their yielding characteristics at deeper cover based on field and simulation results.

关键词： Pillar yielding mechanisms Great depth Numerical modeling Induced stress Pillar dilation Slippery slickenside layer

Photo-induced Ag modulating carbon dots:Greatly improved fluorescent properties and derived sensing application

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Chinese Chemical Letters 2024年第1期35卷 338-342页

作者： Yuwei Wang Ye Li Guixiang Yang Xiaofeng Yang Chenglu Yan Huaqiao Peng Huiyong Wang Juan Du Baozhan Zheng Yong Guo Department of Chemistry Sichuan UniversityChengdu 610064China institute of Quality Standard and Testing Technology for Agro-products Sichuan Academy of Agricultural SciencesChengdu 610066China Key Laboratory of Aviation fuel&Chemical Airworthiness and Green development The Second Research Institute of Civil Aviation Administration of ChinaChengdu 610041China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical ***,the disadvantage of lower quantum yield(QY)still limits its wide ***,we reported a novel and convenient strategy to prepare photo-induced Ag/CDs(p-Ag/CDs)by irradiating the mixed Ag+and hydrophobic CDs(h-CDs)acetone solution with ultraviolet(UV)*** obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift(460 nm)than h-CDs(520 nm).The QY of p-Ag/CDs is measured to be 51.1%,which is 10.4 times higher than that of h-CDs(4.9%),indicating that photo-induced Ag modulation can effectively improve the optical properties of *** mechanisms for the FL enhancement and blue shift of h-CDs are studied in *** results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles(AgNPs)by UV light irradiation based on metal-enhanced fluorescence(MEF),and the increased oxygen-contained groups in this process lead to the blue shift in CDs ***,the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions(S2-)detection than that of h-CDs,which have a lower response to S2-.This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields.

关键词： Carbon dots Photo-induced Ag modulating Fluorescent enhancement High quantum yield Derived sensing application Sulfide determination

Lacustrine biomass: An significant precursor of high wax oil

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Chinese Science Bulletin 2003年第18期48卷 1987-1994页

作者： Haiping Huang Yabin Zheng Zhanwen Zhang Jinyou Li China University of Geosciences Beijing China Fossil fuel and Environmental Geochemistry University of Newcastle upon Tyne Newcastle upon Tyne UK Scientific institute of Petroleum Exploration and development Liaohe Oilfield Company China National Petroleum Corporation Panjing China

Although a variety of precursors have been proposed for the formation of high molecular weight hydro-carbons (HMWHCs) in crude oil, their precise origin re-mains elusive. Quantitative studies of macrocrystalline wax and microcrystalline wax content of source rock extracts from the Damintun depression, Liaohe Basin, a typical high wax producing area, coupled with microscopical maceral composition studies and pyrolysis-GC analysis indicate that oil shale enriched in lacustrine biomass makes a primary contribution to wax in oil. The main precursors of high wax oil are lacustrine alginites and their amorphous matrix, which are highly aliphatic in nature and have high genera-tive potential for HMWHCs. Wax generation efficiency could be affected by organic material abundance and matur-ity. The high abundance and low maturity of organic mate-rial are favorite for the formation of high quantity of wax, which declines with decreasing organic abundance and in-creasing thermal maturity. This suggests that wax is derived from organic-rich lacustrine biomass at early stages of maturation (RO = 0.4%—0.7%). Although the contribution of high plant cuticular wax and sporopollen cannot be ruled out, lacustrine biomass is more important in the formation of high wax oil.

关键词： high wax oil precursor microalgae maturity HTGC Damintun depression.

Facile preparation of unique three-dimensional(3D)α-MnCh/MWCNTs macroporous hybrid as the high-performance cathode of rechargeable Li-O2 batteries

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Nano research 2019年第1期12卷 69-75页

作者： Shuiyun Shen Aiming Wu Guofeng Xia Guanghua Wei Xiaohui Yan Yao Zhang Fengjuan Zhu Jiewei Yin Junliang Zhang institute of fuel Cells School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China SJTU-Paris Tech Elite institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

Un doubtedly,there remai ns an urge nt prerequisite to achieve sign ifica nt adva nces in both the specific capacity and cyclability of Li-O2 batteries for their practical *** this work,a series of unique three-dimensional(3D)α-MnO2/MWCNTs hybrids are successfully prepared using a facile lyophilization method and investigated as the cathode of Li-O2 ***,cross-1 inkedα-MnO2/MWCNTs nano composites are first syn thesized via a modified chemical *** dem on strate that MnO2 nano rods in the nano composites have a length of 100-400 nm and a diameter ranging from 5 to 10 nm,and more attractively,the as-lyophilized 3D MnO2/MWCNTs hybrids is uniquely constructed with large amounts of interconnected macroporous *** U-O2 battery with the 3D macroporous hybrid cathode that has a mass percentage of 50%ofα-MnO2 delivers a high discharge specific capacity of 8,643 mAh·g^-1 at 100 mA·g^-1,and main tains over 90 cycles before the discharge voltage drops to 2.0 V un der a controlled specific capacity of 1,000 mAh·g^-*** is observed that when being recharged,the product of toroidal Li2O2 particles disappears and electrode surfaces are well recovered,thus confirming a good *** excellent performanee of Li-O2 battery with the 3Dα-MnO2/MWCNTs macroporous hybrid cathode is ascribed to a syn ergistic com bination betwee n the unique macroporous architecture and highly efficient bi-fun ctionalα-MnO2/MWCNTs electrocatalyst.

关键词： α-MnO2/MWCNTs lyophilization specific capacity cyclability lithium-oxygen batteries

Integrated Analysis of the Trees and Associated UnderCanopy Species in a Subalpine Forest of Western Himalaya,Uttarakhand, India

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Journal of Mountain Science 2015年第1期12卷 154-165页

作者： Vinod K.BISHT Chandra P.KUNIYAL Bhagwati P.NAUTIYAL Pratti Prasad Herbal research and development institute Department of Horticulture Aromatic and Medicinal Plants School of Earth Sciences and Natural Resources Management Mizoram University High Altitude Plants Physiology research Centre HNB Garhwal (Central) University

Subalpine forests are known as outstanding habitats due to co-existence of both temperate and alpine vegetation and are classic example of ecotonal zones. Limited but diverse physiognomy of trees inhabiting in subalpine forest results in variability within under-canopy habitat conditions. Studies were undertaken to assess population status, habitat preference and interferences to the trees and associated under-canopy herbs in a subalpine forest of western Himalaya. A total of lo woody and 23 under-canopy herbs were recorded in the selected subalpine forest area. At each stand, the number of tree species and under-canopy herbs ranged from 2 to 4 and 8 to lo respectively. Abies spectabilis, Acer caesium, Quercus floribunda, Q. semecarpifolia and Rhododendron arboreum were key tree species in this area. The density of main woody species was 280 to 119o individuals ha-1 at different stands. Herbaceous plants with rosette and clump growth habits were observed to have higher values for total basal cover and importance value index. Presence of some under- canopy herbs like; Dactylorhiza hatagirea, Malaxis muscifera, Picrorhiza kurrooa, Polygonatum cirrhifolium habitats also and Skimmia laureola showed that they are in the habitat specific specific. However, the presence of Frageria nubicola and Viola sp. was common in the selected stands. Felling of trees for timber, construction of temporary huts, fuel wood and lopping for fodder were main interferences for trees. On the other hand, trampling driven damage due to grazing, habitats degradation and overexploitation were observed key threats for under-canopy herbs. Integrated analysis including population studies, habitats preference and interferences to the trees and under-canopy herbs in this sensitive and important ecosystem will be useful for determining the conservation plans and ecosystem management.

关键词： Conservation Habitat preferences Interferences Management Population analysis

Coal measure metallogeny:Metallogenic system and implication for resource and environment

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Science China Earth Sciences 2022年第7期65卷 1211-1228页

作者： Yong LI Songqi PAN Shuzheng NING Longyi SHAO Zhenhua JING Zhuangsen WANG China University of Mining and Technology(Beijing) Beijing 100083China research institute of Petroleum Exploration and development Beijing 100083China China National Administration of Coal Geology Beijing 100039China

Coal,coal measure gas,coal conversion to oil and gas,and coal-based new materials are reliable guarantees for stable energy supply and economic and social development in *** coal-dominated resource endowment and the economic and social development stage determine the irreplaceable position of coal resources in the energy *** measure resources,including aggregated or dispersed solids,liquid and gaseous multitype energies,and metal as well as nonmetallic minerals,are the products of multisphere interaction and metallogenetic materials generation,migration,and *** measures record rich deep-time geological information of transitional and terrestrial peat bogs,which is a crucial carrier to reveal ecosystem evolution,significant organic carbon sequestration,atmospheric O_(2)/CO_(2)variation,and wildfire *** measure evolution is accompanied by the migration and transformation of various materials during diagenesis-metamorphism,forming differentiated coal compositions besides properties and various mineral resources in its adjacent *** enrichment condition,occurrence state,and separation potential are the premise for level-by-level use and efficient development of coal measure *** measure metallogeny is based on the metallogenic system of multiple energy and mineral resources in coal measures and their environmental *** understanding coal measure metallogeny is beneficial for promoting the coal transition from fuel to raw materials and strengthening its attribute of multiple mineral *** metallogeny comprises various aspects,including:(1)the symbiosis mechanism,co-exploration and co-mining conditions of various resources;(2)the source-sink system of ore-forming materials;(3)the differential carbon accumulation and hydrogen enrichment effect;(4)organic(coal and hydrocarbon)and inorganic(mineral)interactions;and(5)combination of minerals naturally enrichment during the metallogenic process and artificial

关键词： Coal geology Coal measure resources Coal measure critical metals Coal measure natural gas Earth system

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Microstructure, hardness and contact fatigue properties of X30N high nitrogen stainless bearing steel

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Journal of Iron and Steel research International 2018年第9期25卷 954-967页

作者： Hai-feng Xu Gui-lin Wu Chang Wang Jian Li Wen-quan Cao Special Steel institute Central Iron and Steel Research Institute Beijing 100081 China College of Materials Science and Engineering Chongqing University Chongqing 400045 China Central Laboratory Central Iron and Steel Research InstituteBeijing 100081 China Center for fuel Cell Innovation State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China

Microstructure, hardness and fatigue properties of X30N high nitrogen stainless bearing steel were investigated. It was found that nitrogen addition could effectively reduce the amount and size of coarse carbides. The original austenite grain size was obviously refined. Additionally, more retained austenite was found in X30N steel after quenching at 1050 ℃, which could be reduced from about 30% to about 6% by cold treatment at - 73 ℃ and subsequent tempering, and thus, the ultimate hardness was increased up to about 61 HRC with reduction of austenite and precipitation of carbonitrides. Furthermore, the rolling contact fatigue lives of X30N steel ate superior to those of 440C steel, which was attributed to the enhanced hardness and a certain retained austenite in the high nitrogen steel.

关键词： Nitrogen addition Grain refining High hardness Ultrafine precipitate Contact fatigue life High nitrogen stainless bearing steel