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Acta Mechanica Sinica 2011年第5期27卷 649-659页

作者： Xiao-hong Wang Zheng-feng liu Xiao-Xia Lu Department of Thermal Science and Energy Engineering University of Science and Technology of China230026 Hefei China

With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic *** a low-order two-scale expansion,applying the mode coupling approximation in the Yakhot-Orszag renormalization group method to analyze the fluctuating field,the Reynolds-average terms in the Reynolds stress transport equation,such as the convective term,the pressure-gradient-velocity correlation term and the dissipation term,are *** numerical examples：turbulent flow past a backward-facing step and the fully developed flow in a rotating channel,are presented for testing the efficiency of the proposed second-order *** these two numerical examples,the proposed model performs as well as the Gibson-Launder （GL） model,giving better prediction than the standard k-ε model,especially in the abilities to calculate the secondary flow in the backward-facing step flow and to capture the asymmetric turbulent structure caused by frame rotation.

关键词： Turbulent modeling Renormalization group Two-scale expansion Reynolds stress transport equation Second-order model

Vapor-phase Nitration of Benzene to Nitrobenzene over Supported Sulfuric Acid Catalyst

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Chinese Chemical Letters 2002年第4期13卷 311-314页

作者： Jing Lin CHEN Wei Guo CHENG hong feng liu Qing Song LIN Lian Hai LU State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116012

Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent, and found that supported sulfuric acid catalyst exhibited a very high catalytic activity. Under the conditions of reaction temperature 160-170℃, space velocity (SV) 1200 h-1, the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg穔gcat-1穐-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively.

关键词： Nitration (vapor-phase) sulfuric acid (supported catalyst) nitrobenzene

IP Network Management Model Based on NGOSS

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The Journal of China Universities of Posts and Telecommunications 2004年第Z1期11卷 107-111页

作者： ZHANG Jin-yu LI hong-hui liu feng School of Computer & Information Technology Beijing Jiaotong University Beijing 100044 P.R. China School of Computer & Information Technology Beijing Jiaotong University Beijing 100044 P.R. China School of Computer & Information Technology Beijing Jiaotong University Beijing 100044 P.R. China

This paper addresses a management model for IP network based on Next Generation Operation Support System (NGOSS). It makes the network management on the base of all the operation actions of ISP, It provides QoS to user service through the whole path by providing end-to-end Service Level Agreements (SLA) management through whole path. Based on web and coordination technology, this paper gives an implement architecture of this model.

关键词： IP QoS network management NGOSS

New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 473-484页

作者： Qipeng Bao Lei Guo hong Yong Sohn Haibin Zuo feng liu Yongliang Gao Zhancheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Department of Materials Science&Engineering University of UtahUtah 84112USA China ENFI Engineering Corporation Beijing 100038China

Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional *** study proposed a new treatment called flash reduction-melting separation(FRMS)for boron-bearing iron *** this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle *** reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRMS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw *** mineral phase transformation and morphology evolution in the ore particles during FRMS were also comprehensively analyzed.

关键词： ludwigite boron-bearing iron concentrate flash reduction melting separation boron

Atomization characteristics of pyrolysis oil derived from waste tires

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Waste Disposal and Sustainable Energy 2024年第1期6卷 39-52页

作者： hong feng Zhitong Yin Qin hong Yiming Hu Lintao liu Jun Wang Qunxing Huang Yonggang Zhou ZJMI Environmental Energy Co. LtdHangzhou310003China Tongxiang Taiaisi Environmental Protection Energy Co. Ltd.Jiaxing314500China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou310027China Key Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province Jiaxing Research InstituteZhejiang UniversityJiaxing314031China

The atomization characteristics play a key role in the highly efficient combustion of pyrolysis oil derived from waste *** this study,the fuel properties of tire pyrolysis oil(TPO)were initially studied,and then a high-speed camera and a phase Doppler particle analyzer were employed to characterize the atomization feature of *** influence of pressure and nozzle orifice diameter on atomization characteristics such as spray angle,droplet velocity,and droplet size distribution was *** results showed that TPO had a high calorific value of about 43.6 MJ/kg and a low viscosity of 3.84×10^(–6)m^(2)/s at 40℃,which made it have the potential to be used as an alternative *** pressure expanded the spray angle and extended the spray in both the axial and radial *** increasing pressure,spray angle and droplet velocity raised,and the increase in crushing effect of air reduced the Sauter mean diameter(SMD)of the *** obtain proper atomization quality for combustion,the pressure is expected to be higher than 1.25 *** increasing nozzle orifice diameter,droplet velocity increased,and the SMD of the droplets increased as well due to weakened crushing effect of the ***,the pressure must be increased to maintain the atomization quality when using a nozzle with a larger *** to the lower viscosity,the velocity and particle size distribution of TPO droplets after atomization were smaller than those of diesel *** extremely small carbon black contained in TPO also contributed to the breaking of droplets and played a certain role in the size reduction of the oil droplets,but it may cause the risk of nozzle *** summary,TPO showed great atomization characteristics for alternative fuel applications.

关键词： Pyrolysis oil Atomization characteristics Spray angle Droplet velocity Droplet size distribution

Prediction for permeability index of blast furnace based on VMD-PSO-BP model

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Journal of Iron and Steel Research International 2024年第3期31卷 573-583页

作者： Xiao-jie liu Yu-jie Zhang Xin Li Zhi-feng Zhang hong-yang Li Ran liu Shu-jun Chen School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Chengde Branch HBIS Group Co.Ltd.Chengde 067000HebeiChina

The permeability index is one of the important production indicators to monitor the operation of blast *** is crucial to grasp the trends of changes in the new permeability index in *** the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was ***,the key factors that affect the permeability index of blast furnace were studied from multiple ***,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each ***,the prediction results of each sub-mode were summed to obtain the final *** results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.

关键词： Big data-Blast furnace Air permeability Variational mode decomposition Particle swarm optimization Back propagation Model prediction

Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science China Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing Gu hong-Xin Long Dan-Dan Zhang Mei-feng Ruan Guo-Kai liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

Opportunities and challenges of high-entropy materials in lithium-ion batteries

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Rare Metals 2024年第10期43卷 4884-4902页

作者： Tong-Yue Xu Huai-Wei feng Wei liu Yan Wang hong-He Zheng College of Energy&Jiangsu Key Laboratory of Advanced Negative Carbon Technologies& Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow University NARI Technology Co. Ltd.

Lithium-ion batteries(LIBs) currently occupy an important position in the energy storage market, and the development of advanced LIBs with higher energy density and power density, better cycle life and safety is a hot topic for both academia and industry. In recent years, high-entropy materials(HEMs) with complex stoichiometric ratios have attracted great attention in the field of LIBs due to their various promising functional properties. The adjustability and synergistic effects of multiple elements in HEMs make them possible to break through the bottleneck of traditional electrode materials and electrolytes, providing new opportunities for the development of high-performance LIBs. This article provides an overview of the opportunities and challenges of HEMs in LIBs, including cathodes, anodes and electrolytes. The progress of HEMs in LIBs is first summarized and analyzed, then the potential advantages and limitations of HEMs used in LIBs are concluded, finally some envisioned solutions are proposed to develop more advanced LIBs through HEMs.

关键词： Lithium-ion batteries

A study that redefines the concept of a well-known orchid–pollinator attraction strategy

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National Science Review 2024年第5期11卷 98-99页

作者： hong liu Department of Earth and Environment International Center for Tropical Botany Florida International University The Fairchild Tropical Botanic Garden

Zhang and collaborators [1] demonstrated that bees of the genus Ctenoplectra collect oil from the newly reported oilreward orchids of the genera Dendrobium and Galeola in Asia, and that the majority of the bees that carry out this act and pollinate the orchids are male. These are new discoveries with significant implications for biodiversity conservation.

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Risk Factors of Depression Screened by Two-Sample Mendelian Randomization Analysis:A Systematic Review

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Biomedical and Environmental Sciences 2024年第1期37卷 85-95页

作者： WANG Han Lin XUE Yan feng CUI Bao Qiu liu hong SHEN Xin Xin Shandong Provincial Research Center for Bioinformatic Engineering and Technique School of Life SciencesShandong University of TechnologyZibo 255049ShandongChina Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuan 030013ShanxiChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with *** We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 *** MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for *** variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary *** The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for ***,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of *** contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against *** This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.

关键词： Risk factors Drug targets Depression Major depressive disorder Two-sample Mendelian randomization