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Microscopic and spectroscopic analysis of atmospheric iron-containing single particles in Lhasa,Tibet

Journal of Environmental Sciences 2024年第7期141卷 40-50页

作者： Junyu Chen Daobin Zhang Yiran Fu Jinhu Wang Xiaomei Cui Ci-ren qu-zong Qiangying Zhang Chan Jin Bu Duo School of Ecology and Environment Tibet UniversityLhasa 850000China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

The Tibetan Plateau,known as the“Third Pole”,is currently in a state of perturbation caused by intensified human activity.In this study,56 samples were obtained at the five sampling sites in typical area of Lhasa city and their physical and chemical properties were investigated by TEM/EDS,STXM,and NEXAFS spectroscopy.After careful examination of 3387single particles,the results showed that Fe should be one of the most frequent metal elements.The Fe-containing single particles in irregular shape and micrometer size was about7.8%and might be mainly from local sources.Meanwhile,the Fe was located on the subsurface of single particles and might be existed in the form of iron oxide.Interestingly,the core-shell structure of iron-containing particles were about 38.8%and might be present as single-,dual-or triple-core shell structure and multi-core shell structure with the Fe/Si ratios of 17.5,10.5,2.9 and 1.2,respectively.Meanwhile,iron and manganese were found to coexist with identical distributions in the single particles,which might induce a synergistic effect between iron and manganese in catalytic oxidation.Finally,the solid spherical structure of Fe-containing particles without an external layer were about 53.4%.The elements of Fe and Mn were co-existed,and might be presented as iron oxide-manganese oxide-silica composite.Moreover,the ferrous and ferric forms of iron might be co-existed.Such information can be valuable in expanding our understanding of Fe-containing particles in the Tibetan Plateau atmosphere.

关键词： Fe-containing single particle Irregular shape Core-shell structure Solid spherical structure Transmission electron microscopy Synchrotron X-ray microscopy

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Multifunctional polyeugenol-based nanoparticles with antioxidant and antibacterial properties

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Particuology 2024年第4期87卷 194-204页

作者： Qiaoqiao Lan Xuying Zhang Jiaming Liang Wei Wang Leili Lv Jiamin He Zefeng Wang Chunsheng qu The People's Hospital of Lishui Lishui323000China College of Ecology Lishui UniversityLishui32300China R&D Center of Green Manufacturing New Materials and Technology of Synthetic Leather Sichuan University-Lishui University Lishui323000China

Over the past few decades,extensive scientific has been dedicated to polymer synthesis employing renewable resources.In this study,we devised and synthesized multifunctional polyeugenol-based nanoparticles,exhibiting remarkable antioxidant and antibacterial properties.The grafting of eugenol onto the nanoparticle surface was achieved via a thiol-ene chemical reaction with a grafting rate of 3.5%.To comprehend the properties of the synthesized nanoparticles,we employed Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy and pyrolysis-gas chromatography mass spectrometry.Subsequent scanning electron microscopic and transmission electron microscopic analyses revealed the presence of a crosslinked structure within the polyeugenol-based nanoparticles,as well as a heteroge-neous microsphere structure on the surface.Due to the inherent crosslinking structure,the polyeugenol-based nanoparticles demonstrated robust the resistance to solvents,as ascertained through thermog-ravimetric analysis and solvent resistance tests.Notably,nitrogen adsorption/desorption studies confirmed the adsorption capacity of the polyeugenol-based nanoparticles,rendering them potentially suitable for drug transport applications.Moreover,the assays for assessing cytocompatibility and reactive oxygen species scavenging activities demonstrated better performance of the eugenol-based nano-particles compared to eugenol.Furthermore,the polyeugenol-based nanoparticles exhibited certain bactericidal activities against Escherichia coli,Staphylococcus aureus,and Fusobacterium nucleatum.Consequently,these observations indicated the nontoxic nature and expansive application prospects of the polyeugenol-based nanoparticles in the domains of medicine and food preservation.This work presented a pioneering concept for the development of antioxidant and antibacterial multifunctional polymer materials derived from eugenol.

关键词： Polyeugenol-based nanoparticles Bactericidal activities Cytocompatibility

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An evolutionary multiobjective method based on dominance and decomposition for feature selection in classification

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Science China(Information Sciences) 2024年第2期67卷 5-19页

作者： Jing LIANG Yuyang ZHANG Ke CHEN Boyang qu Kunjie YU Caitong YUE Ponnuthurai Nagaratnam SUGANTHAN School of Electrical and Information Engineering Zhengzhou University State Key Laboratory of Intelligent Agricultural Power Equipment School of Electrical Engineering and Automation Henan Institute of Technology School of Electronics and Information Zhongyuan University of Technology KINDI Center for Computing Research College of EngineeringQatar University

Feature selection in classification can be considered a multiobjective problem with the objectives of increasing classification accuracy and decreasing the size of the selected feature subset. Dominance-based and decomposition-based multiobjective evolutionary algorithms(MOEAs) have been extensively used to address the feature selection problem due to their strong global search capability. However, most of them face the problem of not effectively balancing convergence and diversity during the evolutionary process. In addressing the aforementioned issue, this study proposes a unified evolutionary framework that combines two search forms of dominance and decomposition. The advantages of the two search methods assist one another in escaping the local optimum and inclining toward a balance of convergence and diversity. Specifically, an improved environmental selection strategy based on the distributions of individuals in the objective space is presented to avoid duplicate feature subsets. Furthermore, a novel knowledge transfer mechanism that considers evolutionary characteristics is developed, allowing for the effective implementation of positive knowledge transfer between dominance-based and decomposition-based feature selection methods. The experimental results demonstrate that the proposed algorithm can evolve feature subsets with good convergence and diversity in a shorter time compared with 9 state-of-the-art feature selection methods on 20 classification problems.

关键词： evolutionary algorithms feature selection multiobjective optimization knowledge transfer classification

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Analysis of acupoint massage combined with touch on relieving anxiety and pain in patients with oral implant surgery

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World Journal of Psychiatry 2024年第4期14卷 533-540页

作者： Jin-Hong qu Cheng-Cheng Shou Xin He Qin Wang Yue-Xia Fang Department of Stomatology Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina Department of Software R&D Hangzhou Broadlink Technology CoLtd.Hangzhou 311300Zhejiang ProvinceChina Department of Stomatology Hangzhou Red Cross HospitalHangzhou 310003Zhejiang ProvinceChina Department of Cardiovascular Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina Department of Traditional Chinese Medicine Development Hangzhou Lin'an Traditional Chinese Medicine HospitalHangzhou 311300Zhejiang ProvinceChina

BACKGROUND Oral implant surgery is an effective procedure for artificial implants in missing tooth areas under local anesthesia.Because patients under local anesthesia are conscious during this procedure,compared with general anesthesia-related operations,they are more likely to experience negative emotions,such as anxiety and tension.These emotional reactions result in shivering and chills in the limbs,leading to poor doctor-patient cooperation and even avoidance of treatment.In traditional Chinese medicine,it is believed that acupoint massage regulates blood and Qi,dredge menstruation,and relieve pain,which is beneficial for patients’emotional adjustment;however,there are few related clinical studies.AIM To observe the changes in anxiety and pain in patients with oral implant after acupoint massage combined with touch therapy.METHODS One hundred patients undergoing oral implantation in our hospital between May 2020 and May 2023 were randomly divided into control and study groups,according to a random number table,with 50 patients in each group.The control group received routine intervention,and the study group received acupoint massage combined with touch on the basis of the control group.Anxiety[assessed using the Modified Dental Anxiety Scale(MDAS)],pain severity,blood pressure,heart rate,and satisfaction were compared between the two groups.RESULTS Before intervention,the difference in MDAS score between the two groups was not significant(P>0.05),while after the intervention,the MDAS scores decreased in both groups compared with those before the intervention(P0.05).The systolic and diastolic blood pressures and heart rate in the i

关键词： Oral implant Acupoint massage Touch Anxiety Degree of pain

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Evaluating serum CXCL12,sCD22,Lp-PLA2 levels and ratios as biomarkers for diagnosis of Alzheimer's disease

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World Journal of Psychiatry 2024年第3期14卷 380-387页

作者： Zeng-Ling Liu Fei-Fei Hua Lei qu Na Yan Hui-Fang Zhang Department of Neurology Dongying People's HospitalDongying 257000Shandong ProvinceChina

BACKGROUND Grasping the underlying mechanisms of Alzheimer's disease(AD)is still a work in progress,and existing diagnostic techniques encounter various obstacles.Therefore,the discovery of dependable biomarkers is essential for early detection,tracking the disease's advancement,and steering treatment strategies.AIM To explore the diagnostic potential of serum CXCL12,sCD22,Lp-PLA2,and their ratios in AD,aiming to enhance early detection and inform targeted treatment strategies.METHODS The study was conducted in Dongying people's Hospital from January 2021 to December 2022.Participants included 60 AD patients(AD group)and 60 healthy people(control group).Using a prospective case-control design,the levels of CXCL12,sCD22 and Lp-PLA2 and their ratios were detected by enzyme-linked immunosorbent assay kit in the diagnosis of AD.The differences between the two groups were analyzed by statistical methods,and the corresponding ratio was constructed to improve the specificity and sensitivity of diagnosis.RESULTS Serum CXCL12 levels were higher in the AD group(47.2±8.5 ng/mL)than the control group(32.8±5.7 ng/mL,P<0.001),while sCD22 levels were lower(14.3±2.1 ng/mL vs 18.9±3.4 ng/mL,P<0.01).Lp-PLA2 levels were also higher in the AD group(112.5±20.6 ng/mL vs 89.7±15.2 ng/mL,P<0.05).Significant differences were noted in CXCL12/sCD22(3.3 vs 1.7,P<0.001)and Lp-PLA-2/sCD22 ratios(8.0 vs 5.2,P<0.05)between the groups.Receiver operating characteristic analysis confirmed high sensitivity and specificity of these markers and their ratios in distinguishing AD,with area under the curves ranging from CONCLUSION Serum CXCL12 and Lp-PLA2 levels were significantly increased,while sCD22 were significantly decreased,as well as increases in the ratios of CXCL12/sCD22 and Lp-PLA2/sCD22,are closely related to the onset of AD.These biomarkers and their ratios can be used as potential diagnostic indicators for AD,providing an important clinical reference for early intervention and treatment.

关键词： Alzheimer's disease Biomarkers CXCL12 sCD22 Lp-PLA2

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Facile synthesis of hierarchical NiO/NiFe2O4 microsphere composite as efficient visible photocatalyst for 2,4-DCP degradation

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Rare Metals 2024年第4期43卷 1580-1588页

作者： Shabana Shaheen Shuai Xu Ji Bian Amir Zada Zi-Qing Zhang Yang qu Li-Qiang Jing Key Laboratory of Functional Inorganic Materials Chemistry (Ministry of Education) International Joint Research Center and Lab for Catalytic TechnologySchool of Chemistry and Materials ScienceHeilongjiang University Department of Chemistry Abdul Wali Khan University

It is highly desired to develop efficient photocatalysts with recycling property for practical application to degrade toxic pollutants.Herein,nanosheet-assembled NiFe2O4microspheres with commendable activity are successfully synthesized by a facile solvothermal reaction with NH4F as the modifier,and their photoactivities are further improved by coupling with NiO through an in situ growth process.The optimized nickel oxide（NiO）/nickel ferrite（NiFe2O4） microsphere composite（5NiO/NFO-4）exhibits a satisfactory photocatalytic activity for 2,4-dichlorophenol（2,4-DCP） degradation under visible-light irradiation,which is attributed to its wide visible-light response,well-designed hierarchical structure and enhanced charge transfer and separation by coupling NiO as a high-level energy platform to accept electrons.Moreover,it is found that the NiO/NiFe2O4microsphere photocatalysts can be easily collected and recycled owing to the distinctive magnetic properties.This work provides a feasible route to rational design visible-light-driven photocatalysts with high-activity for environmental remediation and purification with good recyclability.

关键词： NiFe 2 O 4 microspheres NiO/NiFe 2 O 4 composite Charge separation Visible-light photocatalysis 2,4-Dichlorophenol degradation

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Flow field, sedimentation, and erosion characteristics around folded linear HDPE sheet sand fence: Numerical simulation study

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Journal of Mountain Science 2024年第1期21卷 113-130页

作者： ZHANG Kai ZHANG Hailong TIAN Jianjin qu Jianjun ZHANG Xingxin WANG Zhenghui XIAO jianhua College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Wind and sand hazards are serious in the Milan Gobi area of the Xinjiang section of the Korla Railway. In order to ensure the safe operation of railroads, there is a need for wind and sand protection in heavily sandy areas. The wind and sand flow in the region is notably bi-directional. To shield railroads from sand, a unique sand fence made of folded linear high-density polyethylene(HDPE) is used, aligning with the principle that the dominant wind direction is perpendicular to the fence. This study employed field observations and numerical simulations to investigate the effectiveness of these HDPE sand fences in altering flow field distribution and offering protection. It also explored how these fences affect the deposition and erosion of sand particles. Findings revealed a significant reduction in wind speed near the fence corner;the minimum horizontal wind speed on the leeward side of the first sand fence(LSF) decreased dramatically from 3 m/s to 0.64 m/s. The vortex area on the LSF markedly impacted horizontal wind speeds. Within the LSF, sand deposition was a primary occurrence. As wind speeds increased, the deposition zone shrank, whereas the positive erosion zone expanded. Close to the folded corners of the HDPE sand fence, there was a notable shift from the positive erosion zone to a deposition zone. Field tests and numerical simulations confirmed the high windproof efficiency(WE) and sand resistance efficiency(SE) in the HDPE sand fence. Folded linear HDPE sheet sand fence can effectively slow down the incoming flow and reduce the sand content, thus achieving good wind and sand protection. This study provides essential theoretical guidance for the design and improvement of wind and sand protection systems in railroad engineering.

关键词： Folded linear HDPE sheet sand fence Numerical simulation Flow field characteristics Protection benefits

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Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China

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Journal of Arid Land 2024年第2期16卷 298-313页

作者： DUN Yaoquan qu Jianjun KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences Northwest UniversityXi'an 710100China Zhongwei Works Section of China Railway Lanzhou Bureau Group Company Limited Zhongwei 755000China

The development of bare patches typically signifies a process of ecosystem degradation.Within the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and sustainability.However,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand patches.Therefore,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis methods.The results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,respectively.The average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in depth.The actively developing sand patches were the largest,and the initial sand patches were the smallest.Throughout the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing trend.In the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with crusts.Vegetation and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional lobe.Factors such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand patches.The results can provide evidence for the future treatment of sand patches and the management of the protection system of Shapotou section of the Baotou

关键词： railway protection system sand patch morphology vegetation characteristic soil property

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Investigation of anisotropic strength criteria for layered rock mass

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1289-1304页

作者： Shuling Huang Jinxin Zhang Xiuli Ding Chuanqing Zhang Gang Han Guoqi Yu Lulu qu Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan430071China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430000China University of Chinese Academy of Sciences Beijing100049China

Layered rock mass is a type of engineering rock mass with sound mechanical anisotropy,which is generally unfavorable to the stability of underground works.To investigate the strength anisotropy of layered rock,the Mohr-Coulomb and Hoek-Brown criteria are introduced to establish the two transverse isotropic strength criteria based on Jaeger's single weak plane theory and maximum axial strain theory,and parameter determination methods.Furthermore,the sensitivity of strength parameters(K 1,K 2,and K 3)that are used to characterize the anisotropy strength of non-sliding failure involved in the strength criteria and confining pressure are investigated.The results demonstrate that strength parameters K 1 and K 2 affect the strength of layered rock samples at all bedding angles except for the bedding angle of 90°and the angle range that can cause the shear sliding failure along the bedding plane.The strength of samples at any bedding angle decreases with increasing K 1,whereas the opposite is for K 2.Except for bedding angles of 0°and 90°and the bedding angle range that can cause the shear sliding along the bedding plane,K 3 has an impact on the strength of rock samples with other bedding angles that the specimens'strength increases with increase of K 3.In addition,the strength of the rock sample increases as confining pressure rises.Furthermore,the uniaxial and triaxial tests of chlorite schist samples were carried out to verify and evaluate the strength criteria proposed in the paper.It shows that the predicted strength is in good agreement with the experimental results.To test the applicability of the strength criterion,the strength data of several types of rock in the literature are compared.Finally,a comparison is made between the fitting effects of the two strength criteria and other available criteria for layered rocks.

关键词： Layered rock Strength anisotropy Strength criterion Experimental verification

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Current observation and analysis based on mooring systems in the Andaman Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 484-491页

作者： Yimeng WANG Jingsong GUO Dapeng qu Zhixin ZHANG Chalermrat SANGMANEE Varintha VASINAMEKHIN Binghuo GUO First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China Phuket Marine Biological Center Department of Marine and Coastal ResourcesPhuket 83000Thailand Marine and Coastal Resources Research&Development Institute Department of Marine and Coastal ResourcesBangkok 10210Thailand

The basic structure and intraseasonal evolution of currents in the southeastern Andaman Sea was analyzed based on data collected in 2017 from two subsurface moorings(C1 and C5).Periodic variation in the upper ocean currents of the Andaman Sea was investigated by combining observational and satellite data.Mooring observations show that rapid changes of current speed and direction occurred in May and June,with a significant increase in current velocity at the C1 mooring.In the second half of the year,southward flow dominated at the C1 mooring,and alternating northward and southward flows were evident at the C5 mooring during the same period but the northward flow prevailed in boreal winter.In addition,analysis of the power spectra of the upper currents revealed that the tidal period at both moorings is primarily semidiurnal with weaker energy than that of the low-frequency currents.The upper ocean currents at the C1 and C5 moorings exhibited intraseasonal variation of 30-60 d and 120 d,while the zonal current at the C1 mooring exhibited a notable period of approximately 180 d.Further analysis indicated that the variability of currents in the Andaman Sea is influenced primarily by equatorial Kelvin waves and Rossby wave packets.Moreover,our results suggest that equatorial Kelvin waves from the eastern Indian Ocean entered the Andaman Sea in the form of Wyrtki Jets and propagated primarily along two distinct pathways during the observation period.In addition to coastal boundary Kelvin waves,it was found that a branch of the Wyrtki Jet that directly enters the Andaman Sea and flows northward along the slope of the continental shelf,and reflected Rossby wave packets by topography.

关键词： mooring observation Wyrtki Jet Rossby waves intraseasonal variation

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