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Numerical simulation of PAHs sorption/desorption on soil with the influence of Tween80

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Journal of Environmental Sciences 2006年第4期18卷 716-720页

作者： CHEN Jing WANG xue-jun HUJun-dong xu fu-liu TAO Shu College of Environmental Science MOE Laboratory of Earth Surface Process Peking University Beijing 100871 China

In this paper, the influences of inionic surfactant Tween80 on polycyclic aromatic hydrocarbons （PAHs） sorption/desorption on artificially contaminated soil were studied, and γ model was applied to simulate the influences. Results showed that, with the use of Tween 80, the sorption behaviors of PAHs on soil altered significantly. Adsorbed Tween 80 increased the sorption amount of PAHs while the dissolved Tween80 increased the apparent solubility of PAHs. These two processes exert influences on the sorption coefficient of PAHs in soil-water system, which can be depicted by apparent sorption coefficient. The partition coefficients （the soil/water partition coefficient of PAHs and surfactants obtained fxom sorption experiments） and statistical parameters used in the amended γ model were obtained in independent experiments. With these parameters, the γ model could provide a satisfactory independent prediction of PAHs release from soil to aqueous phase at two surfactant concentrations.

关键词： Tween80 PAHs soil sorption/desorption γ model

Influence of Heating Rate and Calcining Temperature on Properties of 95 Polycrystalline Alumina Fiber

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China's Refractories 2012年第3期21卷 29-33页

作者： xu Jianfeng fu Shunde liu Libin JIA Jia GAN Xiaoming State Key Laboratory of Advanced Refractories Sinesteel Luoyang Institute of Refractories Research Co.Ltd. Luoyang 471039 China

The swung gel fibers were hea, ted to 400 ℃ at 0. .5 ,1, 1.5,2,2.5,3and4 ℃ min^-1 of heating rate, respectivel, and *** 1 h ; then heated to 600 ℃ at 3 ℃ min ^-1 *** rate amt soaked for 1 h at last calcined m 1 0... 详细信息

关键词： 95 polycrystalline alumina fiber healing rate calcining temperature average single fiber tensile strength

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： Guo-fu xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

On the study of ecosystem health:state of the art

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Journal of Environmental Sciences 2000年第1期12卷 35-40页

作者： xu fu\|liu,TAO Shu (Departemnt of Urban and Environemntal Sciences,Peking University,Beijing 100871,China)

Ecosystem health is a newly proposed concept that sets new goals for environmental management. Its definition, assessment indicators, and assessment methods are reviewed in this paper. Literature shows that the definitions and the assessment indicators cover a wide range of ecosystem health, and they differ in terms of researchers different scientific background. It is concluded that the concept of ecosystem health cannot be defined or understood simply in biological or ethical or aesthetic or historical terms and the assessment should be based on applying several indicators simultaneously to get overall picture of the health or integrity state of an ecosystem.

关键词： ecosystem health environmental management ecological indicators CLC number: X503 Document code: A

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing xu Da-Jian Wu Ying Cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

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内蒙土壤微量元素含量的空间结构特征

地理学报 2000年第3期55卷 337-345页

作者：徐尚平陶澍徐福留曹军北京大学城市与环境学系北京100871

用因子克里格法分析了内蒙地区土壤中 1 0种微量元素含量的空间结构特征。结果显示 ,母质和以土类为代表的表生地球化学作用是影响内蒙土壤中微量元素含量空间分布模式的主要因素。母质因子的空间变异尺度较小 ,而表生地球化学作用因子... 详细信息

用因子克里格法分析了内蒙地区土壤中 1 0种微量元素含量的空间结构特征。结果显示 ,母质和以土类为代表的表生地球化学作用是影响内蒙土壤中微量元素含量空间分布模式的主要因素。母质因子的空间变异尺度较小 ,而表生地球化学作用因子则具有较大变异尺度。整体而言 ,母质的影响强于表生地球化学作用。内蒙土壤中微量元素含量在不同空间尺度具有较为一致的相关特征。

关键词：土壤微量元素因子克里格空间结构

Mutual-structure weighted guided image filtering for depth map restoration

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Optoelectronics Letters 2025年第1期21卷 51-56页

作者： liu Zijian SONG Jian CHEN Quanmin xu Jiangtao Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology School of Microelectronics Tianjin University Spikesee Technology Co. Ltd.

Although guided image filtering(GIF) is known for preserving edges and fast computation, it may produce inaccurate outputs in depth map restoration. In this paper, a novel confidence-weighted GIF called mutual-structure weighted GIF(MSWGIF) is proposed, which replaces the mean filtering strategy in GIF during handling overlapping windows. The confidence value is composed of a depth term and a mutual-structure term, where the depth term is utilized to protect the edges of the output, and the mutual-structure term helps to select accurate windows during the structure characteristics of the guidance image are transferred to the output. Experimental results show that MSWGIF reduces the root mean square error(RMSE) by an average of 12.37%, and the average growth rate of correlation(CORR) is 0.07% on average. Additionally, the average growth rate of structure similarity index measure(SSIM) is 0.34%.

关键词： Wiener filtering

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying Wu Shan Ye Xiangyi liu Yingsheng xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread

Preparation and Performance of Ternary Early Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 130-140页

作者： liu Jian CHEN Meiting JI Xiaoli xu Chao WANG Chunmei Department of Safety Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Efficient Mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of Chemical Engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology