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Optimal proportioning of iron ore in sintering process based on improved multi-objective beluga whale optimisation algorithm

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Journal of Iron and Steel Research International 2024年第7期31卷 1597-1609页

作者： Zong-ping li Xu-dong li xue-tong yan Wu Wen Xiao-xin Zeng Rong-jia Zhu ya-hui Wang ling-zhi Yi Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina College of Automation and Electronic Information Xiangtan UniversityXiangtan 411105HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina

Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered *** address the problems posed by the complex raw material information and numerous constraints in the sintering process,a multi-objective optimisation model for sintering proportioning was established,which takes the proportioning cost and TFe as the optimisation ***,an improved multi-objective beluga whale optimisation(IMOBWO)algorithm was proposed to solve the nonlinear,multi-constrained multi-objective optimisation *** algorithm uses the con-strained non-dominance criterion to deal with the constraint problem in the ***,the algorithm employs an opposite learning strategy and a population guidance mechanism based on angular competition and two-population competition strategy to enhance convergence and population *** actual proportioning of a steel plant indicates that the IMOBWO algorithm applied to the ore proportioning process has good convergence and obtains the uniformly distributed Pareto ***,compared with the actual proportioning scheme,the proportioning cost is reduced by 4.3361¥/t,and the TFe content in the mixture is increased by 0.0367%in the optimal compromise ***,the proposed method effectively balances the cost and total iron,facilitating the comprehensive utilisation of sintered iron ore resources while ensuring quality assurance.

关键词： Sintering process Proportioning Iron ore Multi-objective beluga whale optimisation algorithm Proportioning cost

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Crystal Structure of Scheelite-type liTb(WO4)2 and Multi-color Emitting Properties Doped by Eu^3+

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Chinese Journal of Structural Chemistry 2020年第2期39卷 310-320,187页

作者： xue ya-li ZHAO Dan CUI Xiao-Qi HAN Xiao-yang liU Bao-Zhong FAN yan-Ping College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China

Single crystal of lithium terbium tungstate liTb(WO4)2 has been grown by the flux method. The crystal structure was refined from single-crystal X-ray data. It crystallizes in tetragonal system, space group I41/a with a = 5.1749(9), c = 11.1953(19) ?, V = 299.81(12) ?~3, Z = 2, Mr = 661.56, Dc = 7.328 g/cm^3, F(000) = 560, μ(MoKα) = 49.94 mm^(-1), R(F^2 > 2σ(F^2)) = 0.026 and wR(F^2) = 0.070. It features a typical scheelite-type structure composed of two-direction packing of isolated WO4 tetrahedra. li and Tb atoms in the structure occupy the same crystallographic site. Moreover, a series of solid solution phosphors liTb(1-x)Eux(WO4)2(x = 0.004~0.1) were synthesized by high temperature solid-state reactions. The phosphors could be effectively excited by a wavelength range from 379 to 487 nm, which matches well with the UV and near-UV LED chip. The emission color of the phosphor can be tuned from green, through yellow to red by simply adjusting the relative Eu^(3+) and Tb^(3+) concentration due to the Tb^(3+) to Eu^(3+) energy transfer.

关键词： rare earth compounds crystal structure optical properties phosphor charge transfer

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FibroScan-aspartate transaminase:A superior non-invasive model for diagnosing high-risk metabolic dysfunction-associated steatohepatitis

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World Journal of Gastroenterology 2024年第18期30卷 2440-2453页

作者： Jing-ya Yin Tian-Yuan yang Bing-Qing yang Chen-xue Hou Jun-Nan li Yue li Qi Wang Center of liver Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Pathology Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing institute of infectious disease Beijing 100015China Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)with hepatic histological NAFLD activity score≥4 and fibrosis stage F≥2 is regarded as“at risk”non-alcoholic steatohepatitis(NASH).Based on an international consensus,NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease(MASLD)and metabolic dysfunction-associated steatohepatitis(MASH),respectively;hence,we introduced the term“high-risk MASH”.Diagnostic values of seven non-invasive models,including FibroScan-aspartate transaminase(FAST),fibrosis-4(FIB-4),aspartate transaminase to platelet ratio index(APRI),*** high-risk MASH have rarely been studied and compared in *** To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk *** A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital,between January 2012 and December *** screening for MASLD and the exclusion criteria,279 patients wereincluded and categorized into high-risk and non-high-risk MASH *** threshold values of each model,sensitivity,specificity,positive predictive value(PPV),and negative predictive values(NPV),were *** operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve(AUROC).RESULTS MASLD diagnostic criteria were met by 99.4%patients with *** MASLD population was analyzed in two cohorts:Overall population(279 patients)and the subgroup(117 patients)who underwent liver transient elastography(FibroScan).In the overall population,FIB-4 showed better diagnostic efficacy and higher PPV,with sensitivity,specificity,PPV,NPV,and AUROC of 26.9%,95.2%,73.5%,72.2%,and ***,Forns index,and aspartate transaminase to alanine transaminase ratio(ARR)showed moderate diagnostic efficacy,whereas S index and gamma-glutamyl transpeptidase to platelet ratio(GPR)were relatively *** the sub

关键词： Metabolic dysfunction-associated steatotic liver disease High-risk metabolic dysfunction-associated steatohepatitis Non-invasive models liver biopsy Diagnostic value

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Rainbow Pancyclicity in a Collection of Graphs Under the Dirac-type Condition

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 269-274页

作者： Lu-yi li Ping li xue-liang li Center for Combinatorics and LPMC Nankai UniversityTianjin 300071China School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Let G={Gi:i∈[n]} be a collection of not necessarily distinct n-vertex graphs with the same vertex set V,where G can be seen as an edge-colored(multi)graph and each Gi is the set of edges with color i.A graph F on V is called rainbow if any two edges of F come from different Gis’.We say that G is rainbow pancyclic if there is a rainbow cycle Cℓof lengthℓin G for each integerℓ2[3,n].In 2020,Joos and Kim proved a rainbow version of Dirac’s theorem:Ifδ(Gi)≥2/n for each i∈[n],then there is a rainbow Hamiltonian cycle in *** this paper,under the same condition,we show that G is rainbow pancyclic except that n is even and G consists of n copies of Kn/2,n/*** result supports the famous meta-conjecture posed by Bondy.

关键词： rainbow Hamiltonian cycle rainbow pancyclic meta-conjecture

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Enhancing reversible hydrogen storage performance of 2liBH_(4)–MgH_(2)via in-situ building heterogeneous nucleation sites

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Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei Chen ya-Hui Sun Tian Xu xue-Bin Yu Guang-lin Xia Department of Materials Science Fudan UniversityShanghai 200433China

2liBH_(4)-MgH_(2)composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB_(2)during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles(AT NPs)are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of 2liBH_(4)-MgH_(2)*** the initial H_(2)desorption process,MgAlB_(4)and TiB_(2)that have identical crystal structure and low d-value mismatch with MgB_(2)resulting from the reaction between AT NPs and 2liBH_(4)-MgH_(2)composite serve as effective nucleation sites for the formation of MgB_(2).As a result,the apparent activation energy of the two-step H_(2)desorption of AT NPs doped 2liBH_(4)-MgH_(2)composite are notably decreased to(110.0±5.9)and(119.6±1.4)kJ·mol^(-1),which is 55.5 and 33.5 kJ·mol^(-1)lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H_(2)desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Reversible hydrogen storage Reactive hydride composites Catalytic effects Heterogeneous nucleation

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Elevation of basal lacustrine sediments along the mid-lower reaches of the yangtze River and its implications for the reconstruction of Holocene water levels

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Science China Earth Sciences 2024年第9期67卷 2924-2936页

作者： Shuchun yaO Chunhai li Bin xue Nanjing Institute of Geography and limnology Chinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The middle and lower reaches of the yangtze River,a primary region for freshwater lakes in China,have undergone significant transformations throughout the *** changes,driven by factors such as sea-level rise,climate change,and human activities,have led to the progressive elevation of water levels in this *** a result,a floodplain has emerged,characterized by the formation of numerous shallow lakes along the river ***,the pattern of water-level changes in the main channel of the yangtze River during the Holocene remains *** gap in knowledge poses challenges for understanding sediment transport dynamics,the interactions between the river and its adjacent lakes,and the prevention and control of flood disasters in the yangtze River *** shed light on these issues,our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the yangtze River ***,we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river’s main *** findings reveal that,particularly along the Jingjiang section,the basal elevation of most lakes is lower than the yangtze River’s water level during the dry ***,the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang *** the tidal reach,especially within the Taihu Lake basin,the basal elevation of lakes typically falls below sea ***,lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the yangtze River’s annual average and dry season water *** the widespread presence of lakes along the middle and lower reaches of the yangtze River,our study introduces a new proxy for reconstructing the mean water level of the mid-lower yangtze River in the *** analyzing sediments from Nanyi Lake and Chenyao Lake in the lower yangtze River,we a

关键词： Middle and lower yangtze River Holocene Water level Floodplain lakes Basal sediment elevation

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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi liu xue-Dong li liang Cheng li liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Effects of microenvironment and biological behavior on the paracrine function of stem cells

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Genes & Diseases 2024年第1期11卷 135-147页

作者： Zhixin xue Yunjun liao Ye li The Department of Plastic and Cosmetic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Mesenchymal stem cells(MSCs),the most well-studied cell type in the field of stem cell therapy,have multi-lineage differentiation and self-renewal ***-based thera-pies have been used to treat diverse diseases because of their ability to potently repair tissue and locally restore *** increasing body of evidence demonstrates that paracrine func-tion is central to the effects of MsC-based *** factors,cytokines,chemokines,extracellular matrix components,and extracellular vehicles all contribute to the beneficial ef-fects of MSCs on tissue regeneration and *** paracrine substances secreted by MSCs change depending on the tissue microenvironment and biological *** this review,we discuss the bioactive substances secreted by MsCs depending on the microenvironment and biological behavior and their regulatory mechanisms,which explain their potential to treat human diseases,to provide new ideas for further research and clinical cell-free therapy.

关键词： Bioactive behavior Mesenchymal stem cells Microenvironment Paracrine Secretome

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Voltage-modulated polymer nanopore field-effect transistor for multi-sized nanoparticle detection

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Nanotechnology and Precision Engineering 2024年第3期7卷 79-89页

作者： Feng Zhou lin li Qiannan xue State Key Laboratory of Precision Measurement Technology and Instruments School of Precision Instruments and Optoelectronics EngineeringTianjin UniversityTianjin 300072China

Solid-state nanopores offer a range of distinct advantages over biological nanopores,such as structural diversity and greater stability and durability;this makes them highly promising for high-resolution nanoparticle *** nanopores can exhibit gating characteristics with stress-responsive switches and can demonstrate specificity toward particular *** inspiration from biological nanopores,this paper introduces a novel polymer nanopore with field-effect characteristics,leveraging a conductive polymer in its construction to showcase intriguing gating ***,in this device,the polymer layer serves as the gate,enabling precise control over the source–drain current response inside and outside the pore by simply adjusting the gate *** unique feature allows fine-tuning of the nanopore’s sensitivity to nanoparticles of varying sizes and facilitates its operation in multiple *** results reveal that the developed polymer nanopore field-effect transistor demonstrates remarkable selectivity in detecting nanoparticles of various sizes under different applied *** proposed single device demonstrates the exceptional ability to detect multiple types of nanoparticle,showcasing its immense potential for a wide range of applications in biological-particle analysis and medical diagnostics.

关键词： Nanopipette Polymer nanopore Voltage modulation Nanoparticle detection

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Channel Estimation for Reconfigurable Intelligent Surface Aided Multiuser Millimeter-Wave/THz Systems

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China Communications 2024年第3期21卷 91-103页

作者： Chu Hongyun Pan xue li Baijiang School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

It is assumed that reconfigurable intelligent surface(RIS)is a key technology to enable the potential of mmWave *** passivity of the RIS makes channel estimation difficult because the channel can only be measured at the transceiver and not at the *** this paper,we propose a novel separate channel estimator via exploiting the cascaded sparsity in the continuously valued angular domain of the cascaded channel for the RIS-enabled millimeter-wave/Tera-Hz systems,i.e.,the two-stage estimation method where the cascaded channel is separated into the base station(BS)-RIS and the RIS-user(UE)***,we first reveal the cascaded sparsity,i.e.,the sparsity exists in the hybrid angular domains of BS-RIS and the RIS-UEs separated channels,to construct the specific sparsity structure for RIS enabled multi-user ***,we formulate the channel estimation problem using atomic norm minimization(ANM)to enhance the proposed sparsity structure in the continuous angular domains,where a low-complexity channel estimator via Alternating Direction Method of Multipliers(ADMM)is *** findings demonstrate that the proposed channel estimator outperforms the current state-of-the-arts in terms of performance.

关键词： atomic norm minimization cascaded channel estimation convex optimization mmWave/THz reconfigurable intelligent surface(RIS) sparsity

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