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Journal of Rock Mechanics and geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan Na Zhang Bei Jiang wei Victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

Acyclic Edge Coloring of 1-planar graphs without 4-cycles

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 35-44页

作者： wei-fan Wang Yi-qiao Wang Wan-shun Yang Department of Mathematics Zhejiang Normal UniversityJinhua321004China School of Management Beijing University of Chinese MedicineBeijing100029China School of Mathematics and Information Science Weifang UniversityWeifang261061China

An acyclic edge coloring of a graph g is a proper edge coloring such that there are no bichromatic cycles in *** acyclic chromatic index χ'α(g) of g is the smallest k such that g has an acyclic edge coloring using k *** was conjectured that every simple graph g with maximum degree Δ has χ'_α(g) ≤Δ+2.A1-planar graph is a graph that can be drawn in the plane so that each edge is crossed by at most one other *** this paper,we show that every 1-planar graph g without 4-cycles has χ'_α(g)≤Δ+22.

关键词： 1-planar graph acyclic edge coloring acyclic chromatic index

Kinetic Resolution of Racemic 4-Substituted Chroman-2-ones Through Asymmetric Lactone Hydrogenation

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CCS Chemistry 2024年第10期6卷 2560-2576页

作者： Xiong Wu Hai-Tao Yue Xiao-Dong Zuo Xiao-Hui Yang Pu-cha Yan Jian-Hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryFrontiers Science Center for New Organic MatterNankai UniversityTianjin 300071 Zhejiang Jiuzhou Pharmaceutical Co. Ltd.TaizhouZhejiang 318000

Esters are abundant in natural and synthetic products and their conversion into primary alcohols holds great importance in fine chemical ***,achieving asymmetric hydrogenation(AH)of racemic esters with remote stereocenters via kinetic resolution(KR)remains a formidable challenge due to the difficulties associated with discerning spatially distant *** address this issue,we have designed a hydroxy-assisted strategy that introduces a hydroxy group into racemicβ-aryl esters to facilitate hydrogenation and enhance chiral discrimination through a lactone *** employing chiral Ir-SpiroPAP catalysts,we achieved exceptional AH of racemic 4-substituted chroman-2-ones,lactone form of ortho-hydroxylatedβ-aryl esters,via KR,resulting in impressive selectivity factor(s)values of up to *** approach exhibited significant efficacy for racemic chroman-2-ones containingβ-aryl,alkenyl,alkynyl,and alkyl groups,enabling the synthesis of chiralγ-aryl primary alcohols and the recovery of chiralβ-aryl esters or chroman-2-ones,typically difficult to access using existing *** scalability and broad synthetic applications of this method were exemplified by successfully synthesizing chiral drugs(R)-fesoterodine and enrasentan,alongside various chiral intermediates essential for producing chiral drugs and natural *** promising results highlight the potential of this approach as a powerful tool for synthesizing valuable chiral compounds.

关键词： asymmetric hydrogenation chiralγ-aryl primary alcohols hydrogenation of esters iridium catalysts kinetic resolution

Interfacial engineering through lead binding using crown ethers in perovskite solar cells

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Journal of Energy Chemistry 2024年第5期92卷 263-270页

作者： Sun-Ju Kim YeonJu Kim Ramesh Kumar Chitumalla gayoung Ham Thanh-Danh Nguyen Joonkyung Jang Hyojung cha Jovana Milić Jun-Ho Yum Kevin Sivula Ji-Youn Seo Department of Nano Fusion Technology Pusan National UniversityBusan 46241Republic of Korea Laboratory for Molecular Engineering of Optoelectronic Nanomaterials Institute of Chemical Sciences and EngineeringÉcole Polytechnique Fédérale de Lausanne(EPFL)1015 LausanneSwitzerland Department of Energy Convergence and Climate cha.ge Kyungpook National UniversityDaegu 41566Republic of Korea Department of Hydrogen and Renewable Energy Kyungpook National UniversityDaegu 41566Republic of Korea Adolphe Merkle Institute University of FribourgCH-1700 FribourgSwitzerland

In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative *** study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial *** ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material *** ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation *** crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial *** devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial *** techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative ***,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative *** research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.

关键词： Perovskite solar cells Interfacial passivation Crown ether materials Stability

challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Enhancement of polymyxin B1 production by an artificial microbial consortium of Paenibacillus polymyxa and recombinant Corynebacterium glutamicum producing precursor amino acids

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Synthetic and Systems Biotechnology 2024年第1期9卷 176-185页

作者： Hui-Zhong Sun Si-Yu wei Qiu-Man Xu wei Shang Qing Li Jing-Sheng Cheng Ying-Jin Yuan Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityYaguan Road 135Jinnan DistrictTianjin300350PR China Tianjin Key Laboratory of Animal and Plant Resistance College of Life ScienceTianjin Normal UniversityBinshuixi Road 393Xiqing DistrictTianjin300387PR China Department of Pharmaceutical School of Chemical Engineering and TechnologyTianjin UniversityYaguan Road 135Jinnan DistrictTianjin300350PR China

Polymyxin B,produced by Paenibacillus polymyxa,is used as the last line of defense *** this study,exogenous mixture of precursor amino acids increased the level and proportion of polymyxin B1 in the total of polymyxin B analogs of *** CJX518-AC(PPAC)from 0.15 g/L and 61.8%to 0.33 g/L and 79.9%,*** co-culture of strain PPAC and recombinant Corynebacterium glutamicum-leu01,which produces high levels of threonine,leucine,and isoleucine,increased polymyxin B1 production to 0.64 g/*** strains PPAC and ***-leu01 simultaneously inoculated into an optimized medium with 20 g/L peptone,polymyxin B1 production was increased to 0.97 g/***,the polymyxin B1 production in the co-culture of strains PPAC and ***-leu01 increased to 2.21 g/L after optimized inoculation ratios and fermentation medium with 60 g/L *** study provides a new strategy to improve polymyxin B1 production.

关键词： Polymyxin Co-culture Paenibacillus polymyxa Corynebacterium glutamicum Medium optimization Metabolic precursors

降速剂及其作用位点对丁羟四组元推进剂燃烧性能的影响规律

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火炸药学报 2024年第3期47卷 229-236,I0004页

作者：许睿轩张皓瑞薛智华史良伟吕龙严启龙西北工业大学固体推进全国重点实验室陕西西安710072 中国科学院上海有机化学研究所上海200032

为研究降速剂对丁羟四组元推进剂燃烧性能的影响规律,将典型季铵盐和金刚烷衍生物两种高效降速剂引入核壳结构铝基复合颗粒Al@HMX和AP@Al,使其分别作用于HMX颗粒内部和AP颗粒表面,制备了4种含降速剂的铝基复合颗粒(Al/A@HMX,Al/B@HMX,AP... 详细信息

为研究降速剂对丁羟四组元推进剂燃烧性能的影响规律,将典型季铵盐和金刚烷衍生物两种高效降速剂引入核壳结构铝基复合颗粒Al@HMX和AP@Al,使其分别作用于HMX颗粒内部和AP颗粒表面,制备了4种含降速剂的铝基复合颗粒(Al/A@HMX,Al/B@HMX,AP@Al/A和AP@Al/B);采用扫描电子显微镜对样品形貌进行了表征;采用高速红外相机拍摄推进剂燃烧过程的火焰红外照片,并对推进剂的爆热、密度、点火延迟时间和燃速进行了测试。结果表明,加入惰性降速剂会导致推进剂爆热降低,而Al@HMX复合颗粒能部分抵消这一现象,使推进剂爆热值增加了338 J/g;降速剂能够抑制AP和HMX的热分解过程,使达到AlO辐射峰值前维持低强度的“平台段”;而引入Al@HMX后,推进剂的点火延迟时间比基础配方减小49.4%;在10~20 MPa范围内两种降速剂均能有效降低推进剂燃速,在此基础上采用Al@HMX可使含季铵盐丁羟四组元推进剂20 MPa下的燃速降低7.1 mm/s(38.4%),压强指数降至0.25;当降速剂作用于AP表面时,含质量分数1%季铵盐的推进剂在20 MPa下燃速可降低5.0 mm/s(27.3%)。

关键词：物理化学固体推进剂降速剂铝基复合燃料点火延迟燃烧性能丁羟四组元推进剂声共振

A novel profile modification HPF-Co gel satisfied with fractured low permeability reservoirs in high temperature and high salinity

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Petroleum Science 2024年第1期21卷 683-693页

作者： Ya-Kai Li Ji-Rui Hou wei-Peng Wu Ming Qu Tuo Liang wei-Xin Zhong Yu-Chen Wen Hai-Tong Sun Yi-Nuo Pan China University of Petroleum Beijing Beijing102249China PetroChina Tarim Oilfield Company Korla 841000XinjiangChina Key Laboratory of Improving Oil and gas Recovery of Ministry of Education Northeast Petroleum University Daqing 163318HeilongjiangChina Xi'an Shiyou University Xi'an 710065ShaanxiChina Northwest Oilfield Company SINOPECUrumqi 830011XinjiangChina

Conformance control and water plugging are a widely used EOR method in mature ***,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and high-salinity low permeability ***,a novel conformance control system HPF-Co gel,based on high-temperature stabilizer(CoCl_(2)·H_(2)O,CCH)is *** HPF-Co bulk gel has better performances with high temperature(120℃)and high salinity(1×10^(5)mg/L).According to Sydansk coding system,the gel strength of HPF-Co with CCH is increased to code *** dehydration rate of HPF-Co gel is 32.0%after aging for 150 d at 120℃,showing excellent thermal *** rheological properties of HPF gel and HPF-Co gel are also *** results show that the storage modulus(g′)of HPF-Co gel is always greater than that of HPF *** effect of CCH on the microstructure of the gel is *** results show that the HPF-Co gel with CCH has a denser gel network,and the diameter of the three-dimensional network skeleton is 1.5-3.5μ*** 90 d of aging,HPF-Co gel still has a good three-dimensional *** spectroscopy results show that CCH forms coordination bonds with N and O atoms in the gel amide group,which can suppress the vibration of cross-linked sites and improve the stability at high *** core plugging test determines the optimized polymer gel injection strategy and injection velocity with HPF-Co bulk gel system,plugging rate exceeding 98%.Moreover,the results of subsequent waterflooding recovery can be improved by 17%.

关键词： Low permeability reservoir High-temperature resistant gel Complexation reaction Polymer gel injection strategy Plugging rate Enhanced oil recovery

An efficient recycling strategy to eliminate the residual“impurities”while heal the damaged structure of spent graphite anodes

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green Energy & Environment 2024年第6期9卷 1027-1034页

作者： Dan Yang Ying Yang Haoran Du Yongsheng Ji Mingyuan Ma Yujun Pan Xiaoqun Qi Quan Sun Kaiyuan Shi long Qie Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai201804China State Key Laboratory of Material Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Shuangdeng group Co. Ltd.Taizhou225500China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou510275China

The recycling of graphite from spent lithium-ion batteries(LIBs)is overlooked due to its relatively low added value and the lack of efficient recovering *** reuse the spent graphite anodes,we need to eliminate their useless components(mainly the degraded solid electrolyte interphase,SEI)and reconstruct their damaged ***,a facile and efficient strategy is proposed to recycle the spent graphite on the basis of the careful investigation of the composition of the cycled graphite anodes and the rational design of the regeneration *** regenerated graphite,which is revitalized by calcination treatment and acid leaching,delivers superb rate performance and a high specific capacity of 370 mAh g^(-1)(~99% of its theoretical capacity)after 100 cycles at 0.1 C,superior to the commercial graphite *** improved electrochemical performance could be attributed to unchoked Li^(+) transport channels and enhanced cha.ge transfer reaction due to the effective destruction of the degraded SEI and the full recovery of the damaged structure of the spent *** work clarifies that the electrochemical performance of the regenerated graphite could be deteriorated by even a trace amount of the residual“impurity”and provides a facile method for the efficient regeneration of graphite anodes.

关键词： graphite Anode Regeneration Solid electrolyte interphase Spent lithium-ion battery

geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： Wen-long Dang gang gao Xin-Cai You Ke-Ting Fan Jun Wu De-Wen Lei Wen-Jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of geoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to cha.ges in the organic geochemical characteristics of the source *** cha.ges might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(gC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag