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Experimental investigation of hydrodynamics of liquid-solid mini-fluidized beds

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Particuology 2016年第4期14卷 102-109页

作者： can Tang Mingyan liu Yanjun Li Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Chemical Engineering and Technology Tionjin University Tianjin 300072 China State Key Laboratory of Chemical Engineering (Tianjin University) Tianjin 300072 China

Expanded fluidization behavior in liquid-solid mini-fluidized beds （MFBs） was experimentally investigated using visual measurements. Wall effects in the liquid-solid MFBs were identified and explained. The measured incipient]minimum fluidization liquid velocity （Umf） in the MFBs was 1.67 to 5.25 times higher than that calculated using the Ergun equation when the ratio of solid particle diameter to bed diameter varied from 0.017 to 0.091. The ratio of the Richardson-Zaki （R-Z） exponent obtained by fitting with experimental data to that calculated using the R-Z correlation varied from 0.92 to 0.55. A wider solid particle size distribution resulted in a smaller R-Z exponent. The influence of the solid particle material on Umf and R-Z exponent was negligible.

关键词： Liquid-solid fluidization Mini-fluidized bed Expansion bed Wall effect Particle size distribution

A visible-light-assisted Pd/TiO_(2)gas sensor with carbon nanotubes electrodes for trace formaldehyde detection

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Rare Metals 2024年第1期43卷 257-266页

作者： can liu Qiao-Qiao Zou Bin liu Yong Zhang School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Owing to the ppb-level detection standard toward the toxic and harmful gas,the detection of trace gases has become an important subject in the field of indoor environment ***,the traditional resistive gas sensors hardly meet the requirement due to the weak signal generated by trace gas molecules that are difficult to ***,a visible-light-assisted Pd/TiO_(2)gas sensor is proposed to endow the effective detection of trace formaldehyde(HCHO)gas without heating *** from the enhanced photocatalytic properties of TiO_(2)by Pd decoration,the visible-light-assisted Pd/TiO_(2)gas sensor can detect the HCHO gas as low as80×10^(–9)at room *** successful preparation of nanoscale TiO_(2)sensing layer is facilitated by the ultrathin carbon nanotube interdigital electrode in the gas sensor,which avoids the discontinuity of the sensing layer caused by the excessive thickness of the traditional metal *** addition,the whole preparation process of the Pd/TiO_(2)gas sensor with carbon nanotube electrodes is compatible with mainstream CMOS fabrication technology,which is expected to realize the batch fabrication and micro-integrated application of gas *** is expected that our work can provide a new strategy for the batch preparation of high-performance trace HCHO gas sensors and their future applications in portable electronic devices such as smartphones.

关键词： Visible-light-assisted gas sensor Pd/TiO_(2) Trace HCHO detection Carbon nanotubes electrodes

Local Discontinuous Galerkin Scheme for Space Fractional Allen–Cahn Equation

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Communications on Applied Mathematics and Computation 2020年第1期2卷 73-91页

作者： can Li Shuming liu College of Sciences Xi’an University of TechnologyXi’an 710048China

This paper is concerned with the efficient numerical solution for a space fractional Allen–Cahn(AC)*** on the features of the fractional derivative,we design and analyze a semi-discrete local discontinuous Galerkin(LDG)scheme for the initial-boundary problem of the space fractional AC *** prove the optimal convergence rates of the semi-discrete LDG approximation for smooth ***,we test the accuracy and efficiency of the designed numerical scheme on a uniform grid by three *** simulations show that the space fractional AC equation displays abundant dynamical behaviors.

关键词： Fractional Allen-Cahn equation Local discontinuous Galerkin scheme Error estimates

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan Nie Hong-chang liu Yue liu can Wang Jin-lan Xia wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

Multi-receptive field interaction network for shape from polarization

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Science China(Information Sciences) 2025年第1期68卷 394-395页

作者： Yini PENG Rui liu Zhiyuan ZHANG Zhongyuan WANG Jiayi MA Xin TIAN Electronic Information School Wuhan University Computer Science School Wuhan University Wuhan Institute of Quantum Technology

Shape from polarization (SfP) method can use the polarization information in reflected light to estimate the surface normal of the target,which can further reconstruct the shape of the *** a simple image capture process,it can use low-cost equipment to meet a high precision imaging requirement,which can be used in remote scenes and other applications.

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The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao Longfei He Yangyang liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

数字经济赋能农村产业现代化的内在逻辑、现实挑战及优化路径

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中国流通经济 2025年第1期39卷 14-24页

作者：刘学侠徐文哲温啸宇中共中央党校(国家行政学院) 北京市100091 农业农村部管理干部学院北京市102208

在数字经济迅猛发展的当今时代,各行各业都迎来了新的变革机遇。农村产业体系作为我国经济的基础产业体系,也应把握数字时代新机遇,为发展注入新动力。数字经济赋能农村产业现代化具有全链路深度覆盖的特征。从作用机理看,数字经济依托... 详细信息

在数字经济迅猛发展的当今时代,各行各业都迎来了新的变革机遇。农村产业体系作为我国经济的基础产业体系,也应把握数字时代新机遇,为发展注入新动力。数字经济赋能农村产业现代化具有全链路深度覆盖的特征。从作用机理看,数字经济依托物联网、大数据、人工智能(AI)、生物技术等新兴数字技术,对技术研发、品种繁育、种植养殖到生产加工、物流、销售等农业产业链全过程赋能,促进农业生产的优质化、品牌化、产业化、集约化、规模化、专业化、社会化、绿色化,进而助力乡村产业现代化进程。这不仅能够提升农业生产效率和产品质量,还能够促进农业产业间的融合发展,增强农业产业的整体竞争力。从发展模式看,我国当前的农业经营主体占比最大的仍然是小农户,如何实现小农户与现代农业的有机衔接是农村产业现代化进程中的关键问题。得益于数字经济广覆盖、高效率、非竞争性等特性,通过建立农业社会化服务体系,提供技术支持和市场信息服务,可以帮助小农户提高生产效率,降低成本,增加收入;通过数字技术推动农业产业链的延伸、强化和补充,即“延链”“强链”“补链”,可以帮助小农户将生产活动从种养环节向农产品加工流通等二三产业延伸,提高农户综合收益;通过改善供产销之间的衔接效率,实现订单形势变化与生产组织方式的高度匹配,可以帮助小农户充分发挥资源优势,转化为市场竞争力;通过土地流转的数字化管理,可以帮助小农户提升规模化经营水平,进而提升发展质量;通过数据分析预测作物病虫害发生,可以帮助小农户进行科学农业生产决策,指导精准灌溉施肥,减少资源浪费。

关键词：数字经济农村产业现代化农业产业链土地流转

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei Li Qianqian Liang Li Xu Changsheng Ding Yu liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Derivation of Plastic Specific Work Rate for Equal Area Yield Criterion and Its Application to Rolling

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Journal of Iron and Steel Research International 2010年第4期17卷 34-38页

作者： ZHAO De-wen FANG Qi LI can-ming liu Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

On the basis of the analysis of the hexagons inscribed and circumscribed of the Mises yield circle on the π- plane in Haigh Westergaard stress space, a new equation called equal area linear yield criterion or EA criterion was proposed, and its plastic specific work rate was derived. Then, a generalized worked example of plate rolling was analyzed by the criterion and its corresponding plastic specific work rate. Finally, the precision of the solution was compared with measured roll separation force in plate finish rolling process. It indicates that the calculated results by EA criterion are slightly higher than the measured ones.

关键词： EA yield criterion specific work rate finish rolling analytical solution