Metal smelting have brought severe metal(loid)s contamination to the *** distribution and pollution source analysis for soil metal(loid)s in an abandoned lead/zinc smelter were *** results showed that soil was contami...
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Metal smelting have brought severe metal(loid)s contamination to the *** distribution and pollution source analysis for soil metal(loid)s in an abandoned lead/zinc smelter were *** results showed that soil was contaminated heavily withmetal(loid)*** mean of lead(Pb),arsenic(As),cadmium(Cd),mercury(Hg)and antimony(Sb)content in topsoil is 9.7,8.2,5.0,2.3,and 1.2 times higher than the risk screening value for soil contamination of development land of china(GB36600-2018),*** ismainly enriched in the 0–6mdepth of site soil while As and Pbmainly deposited in the 0–*** spatial distribution of soil metal(loid)s is significantly correlated with the pollution source in the different functional areas of ***,Hg,Sb,Pb and copper(Cu)were mainly distributed in pyrometallurgical area,while Cd,thallium(Tl)and zinc(Zn)was mainly existed in both hydrometallurgical area and raw material storage *** metal(loid)s pollution sources in the abandoned smelter are mainly contributed to the anthropogenic sources,accounting for 84.5%.Specifically,Pb,Tl,As,Hg,Sb and Cumainly from atmospheric deposition(55.9%),Cd and Zn mainly from surface runoff(28.6%),While nickel(Ni)mainly comes from parent material(15.5%).The results clarified the spatial distribution and their sources in different functional areas of the smelter,providing a new thought for the risk prevention and control of metal(loid)s in polluted site soil.
Plate and frame filter press technology has been increasingly applied in the treatment of dredged sediment because of the high dewatering efficiency However, relying solely on filtration is inadequate for optimizing d...
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Plate and frame filter press technology has been increasingly applied in the treatment of dredged sediment because of the high dewatering efficiency However, relying solely on filtration is inadequate for optimizing dewatering progress, thus necessitating the use of conditioning agents for pretreatment. Commonly employed conditioning agents include flocculants and skeleton builders. In this study, the dewatering effects of anionic polyacrylamide (APAM) and chitosan (CS) were investigated both individually and in combination, via settling column experiments and plate and frame filter press tests. The results indicated that the optimal contents were 0.6 parts per thousand APAM and 1.8 parts per thousand CS when used separately and 1.4 parts per thousand CS + 1.0 parts per thousand APAM when used in combination. At these contents, both sedimentation and dewatering processes were significantly enhanced. Additionally, the use of low-alkalinity sulfate aluminate cement (L-SAC) as a skeleton builder to increase the dewatering performance was examined. Scanning electron microscope (SEM) revealed that adding 4% L-SAC reduced the cake-forming time by 50%, increased the dewatered mass of the mud cake, and minimized the mud cake moisture content. The added L-SAC helped stabilize the cake structure, thereby preserving drainage channels during filtration. This research offers theoretical insights for similar engineering projects.
The microstructure of(Nd,Ce)-Fe-B sintered magnets with different diffusion depths was characterized by a magnetic force microscope,and the relationship between the magnetic properties and the local structure of grain...
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The microstructure of(Nd,Ce)-Fe-B sintered magnets with different diffusion depths was characterized by a magnetic force microscope,and the relationship between the magnetic properties and the local structure of grain boundary diffused magnets is *** domains perpendicular to the c-axis(easy magnetization direction)show a typical maze-like pattern,while those parallel to the c-axis show the characte ristics of plate *** significant gradient change is shown in the concentration of Dy with the direction of diffusion from the surface to the *** diffuses along grain boundaries and(Dy,Nd)_(2)Fe_(14)B layer with a high anisotropy field formed around the *** in-situ electron probe micro-analysis/magnetic force microscopy(EPMA/MFM),it is found that the average domain width decreases,and the proportion of single domain grains increases as diffusion depth *** is caused by both the change of concentration and distribution of *** grain boundary diffusion process changes the microstructure and microchemistry inside the magnet,and these local magnetism differences can be reflected by the configuration of the magnetic domain structure.
Introduction:Influenza is a communicable respiratory disease that causes annual epidemics and occasional unpredictable *** study examines the occurrence of two unexpected influenza peaks within the year ***:Influenza-...
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Introduction:Influenza is a communicable respiratory disease that causes annual epidemics and occasional unpredictable *** study examines the occurrence of two unexpected influenza peaks within the year ***:Influenza-like illness(ILI)data were reported,and specimens of ILI were collected by designated surveillance *** cases were confirmed using real-time reverse transcription polymerase chain reaction(rRT-PCR)testing conducted at national surveillance network *** data were then submitted to the Chinese Influenza Surveillance Information ***:From December 2022 to January 2023,influenza activity was minimal until a spring epidemic began in February,peaking in late *** outbreak spread from the north to the south,with A(H1N1)pdm09 being the predominant strain and A(H3N2)also circulating *** positivity rate in northern and southern provincial-level administrative divisions(PLADs)reached 60.0%(week 10)and 60.2%(week 13),respectively,before dropping to below 5%from May to ***,rates surged starting in week 41 in the south and week 44 in the north,peaking at 54.4%(week 50)and 44.0%(week 49),respectively,and remained high until the end of 2023.A(H3N2)became the prevailing strain,with a notable increase in B/Victoria lineage viruses from December,resulting in two peaks during the 2023 influenza ***:The pattern of the influenza epidemic shifted due to the coronavirus disease 2019(COVID-19)outbreak and is gradually returning to its usual seasonal and intensity *** is,therefore,crucial to continuously strengthen influenza surveillance,enhance the influenza surveillance network,and lay the groundwork for advancing integrated surveillance of multiple pathogens in china.
Deconfined quantum critical points(DQCPs)have been proposed as a class of continuous quantum phase transitions occurring between two ordered phases with distinct symmetry-breaking patterns,beyond the conventional fram...
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Deconfined quantum critical points(DQCPs)have been proposed as a class of continuous quantum phase transitions occurring between two ordered phases with distinct symmetry-breaking patterns,beyond the conventional framework of Landau-Ginzburg-Wilson(LGW)*** the DQCP,the system exhibits emergent gauge fields,fractionalized excitations,and enhanced symmetries.
作者：
Weike DengSheng LongJiliang JingDepartment of Physics
Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology
College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China
We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory to include binary sys...
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We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory to include binary systems with slowly spinning black ***,we decompose the equation for the null tetrad component of the gravitationally perturbed Weyl tensorψ_4~B into radial and angular parts,leveraging the second-order approximation of the rotation parameter ***,we derive an analytical solution for the radial equation and observe that our results are contingent upon the parameters a_(2),a_(3),and a,which represent the second-and third-order correction parameters,***,we calculate the energy flux,the radiation-reaction force and the waveform for the“plus”and“cross”modes of the gravitational waves generated by merging slowly spinning binary black holes.
Multiform fractures have a direct impact on the mechanical performance of rock *** accurately identify multiform fractures,the distribution patterns of grayscale and the differential features of fractures in their nei...
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Multiform fractures have a direct impact on the mechanical performance of rock *** accurately identify multiform fractures,the distribution patterns of grayscale and the differential features of fractures in their neighborhoods are *** on this,a multiscale processing algorithm is *** multiscale process is as *** the neighborhood of pixels,a grayscale continuous function is constructed using bilinear interpolation,the smoothing of the grayscale function is realized by Gaussian local filtering,and the grayscale gradient and Hessian matrix are calculated with high *** small-scale blocks,the pixels are classified by adaptively setting the grayscale threshold to identify potential line segments and *** the global image,potential line segments and mini-fillings are spliced together by progressing the block frontier layer-by-layer to identify and mark multiform *** accuracy of identifying multiform fractures is improved by constructing a grayscale continuous function and adaptively setting the grayscale thresholds on small-scale *** the layer-by-layer splicing algorithm is performed only on the domain of the 2-layer small-scale blocks,reducing the *** using rock mass images with different fracture types as examples,the identification results show that the proposed algorithm can accurately identify the multiform fractures,which lays the foundation for calculating the mechanical parameters of rock masses.
What is already known about this topic?Foodborne diseases,representing significant food safety and public health challenges globally,are not welldocumented in terms of incidence,particularly for cases characterized by...
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What is already known about this topic?Foodborne diseases,representing significant food safety and public health challenges globally,are not welldocumented in terms of incidence,particularly for cases characterized by acute gastroenteritis(AGI)in *** is added by this report?This study developed a pyramid model to estimate the incidence of five pathogens,stratified by gender and *** estimated incidences per 100,000 people with 95%uncertainty intervals(UI)are as follows:Norovirus,3,188.28(95%UI:2,518.03,7,296.96);Salmonella spp.,1,295.59(95%UI:1,002.62,1,573.11);diarrheagenic ***(DEC),782.62(95%UI:651.19,932.05);Vibrio parahaemolyticus,404.06(95%UI:342.19,468.93);and Shigella spp.,26.73(95%UI:21.05,33.46).What are the implications for public health practice?This study elucidates the incidence rates across various gender and age groups,thereby identifying priority populations for targeted preventive interventions aimed at reducing disease *** insights are crucial for the development of public health policies and management of food safety risks.
This study addresses the challenge of detecting replay attacks within the stable states in vehicular *** accordance with the zonotopic set-membership filtering algorithm,the detection of attacks is conducted by evalua...
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This study addresses the challenge of detecting replay attacks within the stable states in vehicular *** accordance with the zonotopic set-membership filtering algorithm,the detection of attacks is conducted by evaluating the presence of an intersection between the prediction set and the measurement *** the stable state of the vehicle platoon,replay attacks may potentially bypass attack detectors based on the set-membership filtering *** address the replay attack false negative issue,a watermark design scheme based on Markovian-Bernoulli processes is proposed,and the impacts of this watermark design on system performance and attack detection capability are *** addressing pertinent optimization problems,effective parameters selection for the watermark is achieved,striking a balance between security and control *** effectiveness of this method is validated through numerical simulations.
The green growth impact of global value chain embedding becomes more complex in the context of digital transformation. Based on partially linear functional-coefficient model, this paper used panel data for 16 Chinese ...
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The green growth impact of global value chain embedding becomes more complex in the context of digital transformation. Based on partially linear functional-coefficient model, this paper used panel data for 16 Chinese industrial sectors from 2007 to 2020 to assess the impact and underlying mechanisms of global value chain on green total factor productivity considering the moderating role of digitalization. The results revealed that global value chain position and backward participation caused green productivity to decrease, while forward participation had a non-significant effect. As the digitalization level rose, the impact of global value chain position on green productivity changed from negative to positive. Moreover, green productivity was increasingly inhibited by forward participation, but the adverse effects of backward participation gradually subsided. Actually, digitalization boosted green technological progress effects of global value chain position and backward participation, but impeded the technological progress of forward participation, thus affecting green productivity. Therefore, to achieve green growth, china's industrial sector must accelerate the synergistic development of digital transformation and global value chain, and focus on the different impacts of participation modes.
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