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Study on hydrodynamic diffusion law of the swelling particle slurry in karst pipeline

Particuology 2024年第4期87卷 218-231页

作者： bingchuan cheng Haibo Li Guangming Pan Runhuai Deng Yu'an Gong Shujun Xu Kun Zhou Zhuo Zheng School of Civil Engineering Geotechnical and Structural Engineering Research CenterShandong UniversityJinan250061China The Fourth Prospecting of Shandong Coal Geology Bureau Weifang261000China China Railway 14th Bureau Group Corporation Limited Jinan250101China School of Trafic Engineering Shandong Jianzhu University.Fengming RoadLingang Development ZoneJinan250101China

The swelling particle grouting material has demonstrated remarkable plugging effectiveness in high-pressure and large-flow burst water within karst ***,current research on the rheolog-ical model,flow computation theory,and plugging mechanism of this material is *** conven-tional grouting slurry diffusion process,using the liquid-liquid two-phase flow method,fails to accurately simulate high solubility slurry and particle *** address these limitations,this study established a precise constitutive model to describe the swelling particle slurry diffusion process in dynamic ***,a coupling calculation method was proposed to analyze the spatiotemporal heterogeneity of viscosity during slurry diffusion by considering the migration of slurry and the changes in *** investigate the interaction between particle swelling and flow field changes,a Compu-tational Fluid Dynamics-Discrete Element Method(CFD-DEM)coupling model was developed for the diffusion of swelling particle *** is demonstrated that slurry viscosity increases exponentially within the diffusion front as the particle swelling rate rises,and the drag force exhibits an intriguing behavior of initially increasing and then decreasing as the slurry flows through the ***-more,the CFD-DEM coupling model proved to be more accurate in describing viscosity distribution and diffusion distance compared to the finite element *** primary objective of this paper is to reveal the plugging mechanism and provide theoretical support for the engineering application of the swelling particle grouting material.

关键词： Karst pipeline Swelling particle grouting material Dynamic water diffusion Spatiotemporal variation of viscosity CFD-DEM coupling model

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多溴二苯醚取代特征对其芳香烃受体结合能力的效应分析

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化学学报 2014年第6期72卷 743-750页

作者：姜龙程冰川李鱼华北电力大学资源与环境研究院北京102206 华北电力大学区域能源系统优化教育部重点实验室北京102206

以已知18种多溴二苯醚(polybrominated diphenyl ethers,PBDEs)芳香烃受体结合能力实验值为因变量,构建基于取代基参数的PBDEs芳香烃受体结合能力定量构效关系模型以补足PBDEs芳香烃受体结合能力值,借助全析因实验的分析方法研究不同取... 详细信息

以已知18种多溴二苯醚(polybrominated diphenyl ethers,PBDEs)芳香烃受体结合能力实验值为因变量,构建基于取代基参数的PBDEs芳香烃受体结合能力定量构效关系模型以补足PBDEs芳香烃受体结合能力值,借助全析因实验的分析方法研究不同取代位置对PBDEs芳香烃受体结合能力的主效应及二阶交互效应,并分别从总取代基数、两苯环取代相似性、同一苯环取代基分布性综合研究PBDEs取代特征对芳香烃受体结合能力的影响规律.研究表明:PBDEs芳香烃受体结合能力受各取代位置主效应和二阶交互效应的显著影响,邻位取代基可显著降低PBDEs芳香烃受体结合能力,对位取代基则显著增强,间位取代基主效应较弱,主要通过与邻对位取代基间的二阶交互效应影响PBDEs芳香烃受体结合能力;总取代基数、两苯环取代相似性与PBDEs芳香烃受体结合能力无显著相关性,而同一苯环上取代基间分散性越大,同系物芳香烃受体结合能力越小.

关键词：取代基参数多溴二苯醚芳香烃受体结合能力定量构效关系模型全析因实验相似性分析

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Triple reverse order law for the Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

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Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

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Green Energy & Environment 2024年第3期9卷 481-494页

作者： Long cheng Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous *** adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic ***,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical *** the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

关键词： Biochar MnFe_(2)O_(4) Sulfite Adsorption Photocatalysis

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An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang Jiang Ming cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

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Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua cheng School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

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A historical review of hybrid rice breeding

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Journal of Integrative Plant Biology 2024年第3期66卷 532-545页

作者： Xiaoming Zheng Fei Wei cheng cheng Qian Qian State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National Laboratory Sanya City 572024China

The development of germplasm resources and advances in breeding methods have led to steady increases in yield and quality of rice (Oryza sativa L.). Three milestones in the recent history of rice breeding have contributed to these increases: dwarf rice breeding, hybrid rice breeding, and super rice breeding. On the 50th anniversary of the success of three-line hybrid rice,we highlight important scientific discoveries in rice breeding that were made by Chinese scientists and summarize the broader history of the field. We discuss the strategies that could be used in the future to optimize rice breeding further in the hope that China will continue to play a leading role in international rice breeding.

关键词： Chinese experience dwarf breeding hybrid rice breeding super rice breeding

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Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

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Journal of Iron and Steel Research(International) 2024年第3期31卷 608-621页

作者： Zhe Wang Qi-long Wei cheng-bin Shi Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was *** results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and ***,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of *** increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the *** slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure

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Learning layout generation for virtual worlds

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COMPUTATIONAL VISUAL MEDIA 2024年第3期10卷 577-592页

作者： cheng, Weihao Shan, Ying ARC Lab Shenzhen 518057 Peoples R China

The emergence of the metaverse has led to the rapidly increasing demand for the generation of extensive 3D worlds. We consider that an engaging world is built upon a rational layout of multiple land-use areas (e.g., forest, meadow, and farmland). To this end, we propose a generative model of land-use distribution that learns from geographic data. The model is based on a transformer architecture that generates a 2D map of the land-use layout, which can be conditioned on spatial and semantic controls, depending on whether either one or both are provided. This model enables diverse layout generation with user control and layout expansion by extending borders with partial inputs. To generate high-quality and satisfactory layouts, we devise a geometric objective function that supervises the model to perceive layout shapes and regularize generations using geometric priors. Additionally, we devise a planning objective function that supervises the model to perceive progressive composition demands and suppress generations deviating from controls. To evaluate the spatial distribution of the generations, we train an autoencoder to embed land-use layouts into vectors to enable comparison between the real and generated data using the Wasserstein metric, which is inspired by the Fr & eacute;chet inception distance.

关键词： layout generation virtual worlds Transformer land-use

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Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu SUN Yujian cheng School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

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