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Flotation separation of feldspar from quartz using sodium fluosilicate as a selective depressant

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Rare Metals 2024年第3期43卷 1288-1300页

作者： Xin Hu xian-Ping Luo Zi-Shuai Liu Yong-Bing Zhang he-Peng Zhou zhi-Zhao Yang Xue-Kun Tang Faculty of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Yichun Lithium New Energy Industry Research Institute Jiangxi University of Science and TechnologyYichun336000China

The physical and chemical properties of feldspar and quartz are highly similar,thus they cannot be easily separated *** this work,the flotation separation of feldspar from quartz using sodium fluosilicate(Na_(2)SiF_(6);SF)as a selective depressant was ***,the influence mechanism of SF on the selective flotation separation of feldspar and quartz was investigated via flotation tests,chemical analysis of flotation solution,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and contact angle *** results of the flotation tests show that feld spar and quartz without SF treatment have good *** SF treatment,feldspar still has good floatability,whereas quartz has significantly reduced *** solution chemical analysis shows that the functional group plays an important role in depressing the quartz is[SiF_(6)]^(2-).FTIR,XPS and contact angle analysis results show that[SiF_(6)]^(2-)is adsorbed only on the surface of ***,a thin hydrophilic SiOF layer is generated on the surface,which interferes with the adsorption of the collector on the surface of the *** phenomenon leads to a significant reduction in quartz's ***,SF has a good ability to separate feldspar from quartz by flotation.

关键词： Flotation separation Depressants Sodium fluorosilicate Quartz Feldspar

Spatial covariant gravity with two degrees of freedom in the presence of an auxiliary scalar field:Perturbation analysis

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Chinese Physics C 2024年第8期48卷 198-212页

作者： zhi-Chao Wang xian Gao School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China

We investigate a class of gravity theories respecting only spatial covariance,termed spatially covariant gravity,in the presence of an auxiliary scalar *** examine the conditions on the Lagrangian required to eliminate scalar degrees of freedom,allowing only two tensorial degrees of freedom to *** of strict constraint analysis,in this paper,we employ the perturbation method and focus on the necessary conditions to evade the scalar mode at the linear order in perturbations around a cosmological *** with a general action and solving the auxiliary perturbation variables in terms of a would-be dynamical scalar mode,we derive the condition to remove its kinetic term,thus ensuring that no scalar mode *** an application of the general condition,we study a polynomial-type Lagrangian as a concrete example,in which all monomials are spatially covariant scalars containing two *** find that the auxiliary scalar field is essential,and new terms in the Lagrangian are *** analysis provides insights into constructing gravity theories with two degrees of freedom in the extended framework of spatially covariant gravity.

关键词： modified gravity cosmological perturbation theory gravitational theory

Rational design of ZnCdS/TpPa-1-COF heterostructure photocatalyst by strengthening the interface connection in solar hydrogen production reactions

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Nano Research 2024年第3期17卷 1027-1034页

作者： Di Yang zhi-Gang Li Xinghao Zhang Zenghuan Ren Weihan Lu Haining Liu Xiaomeng Guo Jijie Zhang xian-he Bu Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjin 300350China College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

ZnCdS quantum dots(QDs)are highly coveted in photocatalysis research for their exceptional visible-light responses and high light-absorption ***,their practical application is hindered by their tendency to aggregate,due to having high surface *** address this issue,herein,a heterostructure is synthesized by growing ZnCdS QDs with a size of approximately 5 nm onto the surface of a two-dimensional(2D)covalent organic framework(COF),*** approach suppresses the aggregation of the QDs and improves their *** ZnCdS/TpPa-1-COF composite exhibited a peak hydrogen evolution rate of 6244.16μmol·g^(-1)·h^(-1),which was 2.89 and 4.18 times greater than that of ZnCdS and TpPa-1-COF,*** zero-dimensional/two-dimensional(0D/2D)heterojunction formed by ZnCdS and TpPa-1-COF generates a strong interfacial force,which is attributed to the intimate contact between the *** connections accelerate charge separation,improve the utilisation of reduced electrons,and reduce the extent of agglomeration of the ZnCdS QDs,thereby resulting in high hydrogen production activity of the ***,the photocatalytic mechanism is studied using Kelvin probe force microscopy and theoretical *** study offers a novel approach for creating sulfide photocatalysts and is crucial for investigating the potential practical applications of the related photocatalysts.

关键词： covalent organic frameworks quantum dots photocatalysis hydrogen generation heterojunction

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research International 2024年第3期31卷 670-687页

作者： xian-lei Hu Qin-cheng Xie Yi Yuan Ying zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

计入轴承间隙时轴-滚动轴承系统动力学行为研究

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振动与冲击 2009年第9期28卷 120-124页

作者：何芝仙干洪安徽工程科技学院机械工程系芜湖241000

以6310轴承和轴组成的轴-滚动轴承系统为研究对象,研究变载荷作用下计入轴承间隙时轴-滚动轴承系统动力学问题。首先利用hertz公式和静不定问题的解法(力法)推导出滚动轴承受力与变形关系的计算公式并得到数值解,再以整个轴-滚动轴承系... 详细信息

以6310轴承和轴组成的轴-滚动轴承系统为研究对象,研究变载荷作用下计入轴承间隙时轴-滚动轴承系统动力学问题。首先利用hertz公式和静不定问题的解法(力法)推导出滚动轴承受力与变形关系的计算公式并得到数值解,再以整个轴-滚动轴承系统为研究对象,利用ADAMS动力学仿真软件进行动力学仿真。研究了变载荷作用下刚性轴-滚动轴承系统、弹性轴-滚动轴承系统的幅频特性和动态响应,着重讨论轴承间隙对轴-轴承系统动力学性能的影响。计算结果表明,轴的弹性和轴承间隙对轴-轴承系统的动力学性能影响很大,轴-轴承系统为非线性动力学系统,并随轴承间隙的增加而增强。

关键词：间隙赫兹理论静不定问题轴-滚动轴承系统

计入轴瓦变形的曲轴轴承系统动力学摩擦学耦合分析

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振动与冲击 2008年第10期27卷 139-143页

作者：何芝仙桂长林安徽工程科技学院机械系芜湖241000 合肥工业大学机械与汽车学院

以一四缸柴油机曲轴-轴承系统为研究对象,建立了计入轴瓦弹性变形时弹性曲轴-轴承系统的动力学摩擦学耦合分析模型;采用ADAMS和Matlab联合仿真,在额定工况下进行了弹性曲轴动力学和主轴承摩擦学耦合分析;着重分析了计入轴瓦弹性变形时,... 详细信息

以一四缸柴油机曲轴-轴承系统为研究对象,建立了计入轴瓦弹性变形时弹性曲轴-轴承系统的动力学摩擦学耦合分析模型;采用ADAMS和Matlab联合仿真,在额定工况下进行了弹性曲轴动力学和主轴承摩擦学耦合分析;着重分析了计入轴瓦弹性变形时,主轴承摩擦学行为和曲轴动力学响应之间的相互影响。计算结果表明:计入轴瓦弹性变形,主轴承最小油膜厚度大幅度下降,最大油膜压力大幅度上升或小幅度下降,曲轴轴承系统动力学特性及响应也发生变化。

关键词：弹性曲轴-轴承系统轴瓦弹性变形变形矩阵耦合

Scattering of Water Waves by Dual Symmetric Inclined Floating Porous Barriers Using the DBEM

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China Ocean Engineering 2024年第1期38卷 156-168页

作者： WANG Li-xian DENG Yan-wen YE Yang-sha DENG Zheng-zhi Key Laboratory of High Performance Ship Technology(Wuhan University of Technology) Ministry of EducationWuhan 430063China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China Institute of Port Coastal and Offshore EngineeringZhejiang UniversityZhoushan 316021China

The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave *** that thin barriers are zero-thickness,a novel numerical method involving the the coupling of the dual boundary element method(DBEM)with damping layers is *** order to effectively damp out the reflected waves,two damping layers,instead of pseudoboundaries are implemented near the two side boundaries of the computational ***,the modified linearized free surface boundary conditions are formulated and used for solving both the ordinary boundary integral equation as well as the hypersingular boundary integral equation for degenerate *** newly developed numerical method is validated against analytical methods using the matched eigenfunction expansion method for the special case of two vertical barriers or the inclined angle to the vertical being *** influence of the length of the two damping layers has been ***,these findings are also validated against previous results for several *** validation,the numerical results for the reflection coefficient,transmission coefficient and dissipation coefficient are obtained by varying the inclination angle and porosity-effect *** effects of both the inclination angle and the porosity on the amplitudes of wave forces acting on both the front and rear barriers are also *** is found that the effect of the inclination angle mainly shifts the location of the extremal values of the reflection and the transmission ***,a moderate value of the porosity-parameter is quite effective at dissipating wave energy and mitigating the wave loads on dual barriers.

关键词： dual boundary element method inclined perforated floating breakwater reflection coefficient transmission coefficient damping layer

Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： zhi-Jun Pei xian-zhi Song Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

Gene-Environment Interactions between Environmental Noise and Apo E4 Causes AD-Like Neuropathology in the Hippocampus in Male Rats

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Biomedical and Environmental Sciences 2022年第3期35卷 270-275页

作者： LI Wen Long LI Yuan Yuan LI Yu Xin FU Yu he xian zhi TAO Fei Yan YOU Ruo Lan ZHANG Ruo Yu ZHONG Ming Qing CHI Hui Min ZHAI Qing Feng School of Public health Weifang Medical UniversityWeifang 261042ShandongChina Community healthcare Center of Baoshan Street Office Health Bureau of Licheng DistrictJinan 250000ShandongChina Weifang Maternal and Child health Hospital Weifang 261042ShandongChina

Experimental evidence has demonstrated that environmental hazards can induce neurodegeneration such as Alzheimer's disease(AD)^([1]).The pathogenesis of AD,characterized by a gradual cognitive decline,overproduction ofβ-amyloid(Aβ),and hyperphosphorylated tau in specific brain areas,is considered to involve the interaction of several internal(individual)and external environmental factors.

关键词： Alzheimer Aβ tau