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Journal of Iron and Steel Research International 2024年第5期31卷 1082-1094页

作者： Qing-ke Sun Yao-zu Wang Jian-liang Zhang zheng-jian liu Le-le Niu Chang-dong Shan Yun-fei Ma Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic ***,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was ***,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the *** test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after *** trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.

关键词： Iron ore Basic high-temperature property Machine learning Random forest Genetic algorithm

Joint alignment and steering to manage interference

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Digital Communications and Networks 2024年第2期10卷 429-438页

作者： Zhao Li Xiujuan Liang Yinghou liu Jia liu zheng Yan School of Cyber Engineering Xidian UniversityXi'an710126China Technol.on Commun.Net.Lab. The 54th Research Inst.of China Elec.Technol.Group Corp.Shijiazhuang050081China School of Computer Science and Technology Xidian UniversityXi'an710126China The Department of Communications and Networking(Comnet) Aalto University02150EspooFinland

In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network ***,when managing multiple disturbances from the same source,it may not be feasible to use existing IM methods such as Interference Alignment(IA)and Interference Steering(IS)*** is because with IA,the aligned interference becomes indistinguishable at its desired Receiver(Rx)under the cost constraint of Degrees-of-Freedom(DoF),while with IS,more transmit power will be consumed in the direct and repeated application of IS to each *** remedy these deficiencies,Interference Alignment Steering(IAS)is proposed by incorporating IA and IS and exploiting their advantages in *** IAS,the interfering Transmitter(Tx)first aligns one interference incurred by the transmission of one data stream to a one-dimensional subspace orthogonal to the desired transmission at the interfered Rx,and then the remaining interferences are treated as a whole and steered to the same subspace as the aligned ***,two improved versions of IAS,i.e.,IAS with Full Adjustment at the Interfering Tx(IAS-FAIT)and Interference Steering and Alignment(ISA),are *** former considers the influence of IA on the interfering user-pair's *** orthogonality between the desired signals at the interfered Rx can be maintained by adjusting the spatial characteristics of all interferences and the aligned interference components,thus ensuring the Spectral Efficiency(SE)of the interfering communication *** ISA,the power cost for IS at the interfered Tx is minimized,hence improving SE performance of the interfered *** the proposed methods are realized at the interfering and interfered Txs cooperatively,the expenses of IM are shared by both *** in-depth simulation results show that joint use of IA and

关键词： Interference Interference management Interference alignment Interference steering Spectral efficiency

Sensitivity analysis of modeling parameters to soot and PAHs prediction in ethylene inverse diffusion flame

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Science China(Technological Sciences) 2024年第2期67卷 486-498页

作者： WU BingKun LI TianJiao liu dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and Technology Nanjing 210094China

The soot formation model based on inverse ethylene diffusion flames was performed to study the sensitivity of the soot formation process to the prediction *** effects of efficiency parameters such as soot inception,surface growth and coagulation on the simulation results were studied by using the adjustable efficiency *** addition,the reversible soot model and conjugate heat transfer(CHT)model were also introduced to explore their *** indicated that,among adjustable efficiency parameters,the nucleation efficiency had the greatest influence on the predicted soot and PAHs distributions,while the Habstraction-C2H2-addition(HACA)process and PAH adsorption surface growth efficiencies impacted *** adjustable efficiency parameters had a significant effect on the concentration of soot gaseous precursors and soot particles,but their effects on temperature,gas phase molecules,and intermediate species were not *** the nucleation efficiency increased from 2×10^(-6)to 1×10^(-4),the predicted value of the integrated soot was increased by nearly 50%,and the maximum primary particle number density and the number of aggregates were increased by an order of *** maximum concentration of BAPYR was ***,the peak temperature along the axial direction increased by only 3.5 *** the reversible soot model,the approximation results of the adjustable efficiency parameters could be modified,which showed the feasibility of the *** use of the CHT model promoted pyrolysis of the fuel below the outlet of the fuel tube,with high-temperature zones,soot zones,and PAHs zones moving towards higher flame ***,when using the reversible model and the CHT model,the maximum soot volume fraction decreased by 39%compared with the basic efficiency parameters,while the concentration of BAPYR increased by 162%,and the concentrations of gas phase species were decreased.

关键词： inverse diffusion flames soot formation soot model ethylene

Selenium nanoparticles in aquaculture:Unique advantages in the production of Se-enriched grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2024年第1期16卷 189-201页

作者： Chao Zhu Zifang Wu Qimin liu Xiaolin Wang Lijuan zheng Shuyang He Fangxia Yang Hong Ji Wuzi dong College of Animal Science and Technology Northwest A&F UniversityYanglingShaanxi712100China College of Forestry Northwest A&F UniversityYanglingShaanxi712100China Biology Research Centre of Qin Mountains Wildlife Northwest A&F UniversityYanglingShaanxi712100China

The production of selenium-enriched fish can contribute to alleviating selenium deficiency in human ***,it is still unclear which selenium source,as an additive,can efficiently and costeffectively produce high-quality selenium-enriched *** study evaluated the effects of selenium nanoparticles(SeNP),selenite,and selenomethionine(SeMet)on the growth,antioxidant capacity,selenium content,selenium speciation,and meat quality of grass *** diets were prepared,including a basal diet(BD)and three concentrations(0.1,0.3,and 0.9 mg/kg)of SeNP,selenite,and SeMet.A total of600 fish(250.79±1.57 g)were randomly assigned to 30 tanks(3 tanks/group).Fish were fed the experimental diet three times daily for 60 *** this study,SeNP most significantly promoted the growth and antioxidant capacity of grass carp,with 0.3 mg/kg SeNP identified as the optimal additive ***,SeNP demonstrated equally excellent bioavailability as SeMet and significantly increased the content of SeMet in grass carp(Ctenopharyngodon idella)***,compared to SeMet and selenite,dietary SeNP could more significantly enhance the content of selenocysteine(SeCys2)and methylselenocysteine(MeSeCys)in grass carp muscle *** addition,we have demonstrated that SeCys2and MeSeCys promote apoptosis of cancer cells(HeLa)through the mitochondrial apoptotic pathway(involving Bax and Bcl-2).Furthermore,as an additive,0.3 mg/kg SeNP significantly improved the flesh quality of grass carp by reducing crude fat and heavy metal content,as well as increasing the levels of eicosapentaenoic acid(EPA)and docosahexaenoic acid(DHA)and the ratio of n-3/n-6 polyunsaturated fatty acid(PUFA).In summary,SeNP is the most suitable additive for producing selenium-enriched fish.

关键词： Selenium nanoparticle Speciation analysis Grass carp Selenium additive

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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

Microwave-Assisted Confining Growth and Liquid Exfoliation of sp^(3)-Hybrid Carbon Nitride Nano/Micro-Crystals

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Energy & Environmental Materials 2024年第6期7卷 399-408页

作者： Chenglong Shen Qing Lou Kaikai liu Guangsong zheng Runwei Song Jinhao Zang Xigui Yang Xing Li Lin dong Chongxin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China

As one promising carbon-based material,sp^(3)-hybrid carbon nitride has been predicted with various novel physicochemical ***,the synthesis of sp^(3)-hybrid carbon nitride is still limited by the nanaoscale,low crystallinity,complex source,and expensive ***,we have presented a facile approach to the sp^(3)-hybrid carbon nitride nano/micro-crystals with microwave-assisted confining growth and liquid ***,the carbon nitride nano/micro-crystals can spontaneously emerge and grow in the microwave-assisted polymerization of citric acid and urea,and the liquid exfoliation can break the bulk disorder polymer to retrieve the highly crystalline carbon nitride nano/*** obtained carbon nitride nano/micro-crystals present superior blue light absorption strength and surprising photoluminescence quantum yields of 57.96%in ethanol and 18.05%in solid *** experimental characterizations and density functional theory calculations reveal that the interface-trapped localized exciton may contribute to the excellent intrinsic light emission capability of carbon nitride nano/micro-crystals and the interparticle staggered stacking will prevent the aggregation-caused-quenching ***,the carbon nitride nano/micro-crystals are demonstrated to be potentially useful as the phosphor medium in light-emitting-diode for interrupting blue light-induced eye *** work paves new light on the synthesis strategy of sp^(3)-hybrid carbon nitride materials and thus may push forward the development of multiple carbon nitride research.

关键词： confining growth density functional theory liquid exfoliation luminescence sp^(3)-hybrid carbon nitride

Improving constraint onΩ_(m)from SDSS using marked correlation functions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 207-224页

作者： Limin Lai Jiacheng Ding Xiaolin Luo Yizhao Yang Zihan Wang Keshi liu Guanfu liu Xin Wang Yi zheng Zhaoyu Li Le Zhang Xiao-dong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai CampusZhuhai 519082China Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy Tsinghua UniversityBeijing 100084China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUZhuhai 519082China Peng Cheng Laboratory Shenzhen 518000China

Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological ***,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation *** have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from *** constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et ***.J.948,99(2023))within the 1σ***,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully *** method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological ***,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).

关键词： large scale structure of universe dark energy cosmological parameters marked weighted correlation function

Imbalanced rock burst assessment using variational autoencoder-enhanced gradient boosting algorithms and explainability

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Underground Space 2024年第4期17卷 226-245页

作者： Shan Lin Zenglong Liang Miao dong Hongwei Guo Hong zheng Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University(PolyU)Hung HomKowloon 999077Hong KongChina

We conducted a study to evaluate the potential and robustness of gradient boosting algorithms in rock burst assessment,established a variational autoencoder(VAE)to address the imbalance rock burst dataset,and proposed a multilevel explainable artificial intelligence(XAI)tailored for tree-based ensemble *** collected 537 data from real-world rock burst records and selected four critical features contributing to rock burst ***,we employed data visualization to gain insight into the data’s structure and performed correlation analysis to explore the data distribution and feature ***,we set up a VAE model to generate samples for the minority class due to the imbalanced class *** conjunction with the VAE,we compared and evaluated six state-of-theart ensemble models,including gradient boosting algorithms and the classical logistic regression model,for rock burst *** results indicated that gradient boosting algorithms outperformed the classical single models,and the VAE-classifier outperformed the original classifier,with the VAE-NGBoost model yielding the most favorable *** to other resampling methods combined with NGBoost for imbalanced datasets,such as synthetic minority oversampling technique(SMOTE),SMOTE-edited nearest neighbours(SMOTE-ENN),and SMOTE-tomek links(SMOTE-Tomek),the VAE-NGBoost model yielded the best ***,we developed a multilevel XAI model using feature sensitivity analysis,Tree Shapley Additive exPlanations(Tree SHAP),and Anchor to provide an in-depth exploration of the decision-making mechanics of VAE-NGBoost,further enhancing the accountability of treebased ensemble models in predicting rock burst occurrences.

关键词： Gradient boosting VAE Ensemble learning Explainable artificial intelligence(XAI) Rock burst

Evidence for reversible oxygen ion movement during electrical pulsing:enabler of emerging ferroelectricity in binary oxides

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Materials Futures 2024年第3期3卷 195-205页

作者： Huan liu Fei Yu Bing Chen zheng-dong Luo Jiajia Chen Yong Zhang Ze Feng Hong dong Xiao Yu Yan liu Genquan Han Yue Hao State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an 710071People’s Republic of China Research Center for Intelligent Chips and Devices Zhejiang LabHangzhou 311121People’s Republic of China Engineering Research Center of Thin Film Optoelectronics Technology Ministry of EducationNankai UniversityTianjin 300350People’s Republic of China

Ferroelectric HfO_(2)-based materials and devices show promising potential for applications in information technology but face challenges with inadequate electrostatic control,degraded reliability,and serious variation in effective oxide thickness *** demonstrate a novel interface-type switching strategy to realize ferroelectric characteristics in atomic-scale amorphous binary oxide films,which are formed in oxygen-deficient conditions by atomic layer deposition at low *** approach can avoid the shortcomings of reliability degradation and gate leakage increment in scaling polycrystalline doped HfO_(2)-based *** theoretical modeling and experimental characterization,we show the following.(1)Emerging ferroelectricity exists in ultrathin oxide systems as a result of microscopic ion migration during the switching process.(2)These ferroelectric binary oxide films are governed by an interface-limited switching mechanism,which can be attributed to oxygen vacancy migration and surface defects related to electron(de)trapping.(3)Transistors featuring ultrathin amorphous dielectrics,used for non-volatile memory applications with an operating voltage reduced to±1 V,have also been experimentally *** findings suggest that this strategy is a promising approach to realizing next-generation complementary metal-oxide semiconductors with scalable ferroelectric materials.

关键词： ferroelectric binary oxide mobile ion amorphous dielectric nonvolatile memory

Protein C deficiency with venous and arterial thromboembolic events

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World Journal of Clinical Cases 2024年第12期12卷 2000-2003页

作者： Nan Zhang dong-Kun Sun Xu Tian Xin-Yu zheng Tong liu Department of Cardiology Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular DiseaseTianjin Institute of CardiologyThe Second Hospital of Tianjin Medical UniversityTianjin 300211China

Protein C(PC)is a key component of the vitamin K-dependent coagulation *** exerts anticoagulant effects by inactivating factors V and *** or inherited PC deficiency results in a prothrombotic state,with presentations varying from asymptomatic to venous ***,there has been an increasing number of reports linking PC deficiency to arterial thromboembolic events,such as myocardial infarction and ischemic *** editorial focuses on the association between PC deficiency and thromboembolism,which may provide some insights for treatment strategy and scientific research.

关键词： Protein C deficiency Venous thromboembolism Myocardial infarction Editorial Arterial thromboembolism