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Resonant four-photon photoemission from SnSe_(2)(001)

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Frontiers of physics 2024年第3期19卷 83-92页

作者： chengxiang Jiao Kai Huang Hongli guo Xingxia Cui Qing Yuan Cancan Lou Guangqiang mei Chunlong Wu Nan Xu Limin Cao Min Feng School of Physics and Technology and Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education Wuhan UniversityWuhan 430072China Department of Physics and Astronomy California State University NorthridgeNorthridgeCA 91330-8268USA Institute for Advanced Study Wuhan UniversityWuhan 430072China

High-order nonlinear multiphoton absorption is usually inefficient,but can be enhanced by designing resonant excitations between occupied and unoccupied energy *** conducted angle-resolved multi-photon photoemission(mPPE)studies on the SnSe_(2)(001)surfaces excited by ultrashort laser *** tuning photon energy and light polarization,we demonstrate the presence of a resonant four-photon photoemission(4PPE)process involving the occupied valence band(VB),the unoccupied second conduction band(CB2)and the unoccupied image-potential state(IPs)of SnSe_(2).In this 4PPE process,VB electrons of SnSe_(2) are resonantly excited into CB2 by adsorbing two photons,followed by the adsorption of another photon to populate the n=1 IPs before being emitted out to the vacuum by adsorbing one more *** results in a double-resonant 4PPE process,which exhibits approximately a 40 times enhancement in photoemission yields compared to cases where one of the resonant pathways,CB2→IPs,is inhibited by involving a virtual state instead of the IPs in the *** double-resonant 4PPE process efficiently excite the bulk VB electrons outside the vacuum,like taking advantage of resonant“ladders”through two real empty electronic states of SnSe_(2).Our results highlight the important applications of mPPE in probing the band-structure,particularly the unoccupied states,of recently emerging main group dichalcogenide ***,the discovered resonant mPPE process contributes to the exploration of their promising optoelectronic applications.

关键词： multi-photon photoemission four-photon photoemission SnSe_(2) unoccupied states resonant excitation

Facile preparation of coal-based ultramicroporous carbon microspheres for selective CO_(2)capture

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Carbon Resources Conversion 2024年第3期7卷 97-105页

作者： mei An Tuo guo Qingjie guo Jiangmen Laboratory of Carbon Science and Technology the Hong Kong University of Science and Technology(Guangzhou)JiangmenGuangzhou 529000China State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuanNingxia 750021China Key Laboratory of Clean Chemical Engineering in Universities of Shandong College of Chemical EngineeringQingdao University of Science&TechnologyQingdao 266042China

The basic structure of aromatic compounds that are abundant in coal is the carbonaceous precursor derived from carbon ***,it remains to be a huge challenge to prepare carbon microspheres using coal due to the complex construction and composition of ***,a simple and viable way to obtain coal-based microporous carbon microspheres was developed by means of ethanol pyrolysis and a sequential extraction *** as-prepared carbon microsphere featured aspherical micron particles of a uniform size(0.6-1.6㎛),abundant O-functional groups,excellent thermal stability,high SBET(415.5-983.2 m^(2)/g),and plentiful ultra-micropores(63.15-72.72%).The coal-based carbon microsphere exhibited a noteworthy CO_(2)uptake(3.19-4.97 mmol/g at 273 K and 1.0 bar),acceptable CO_(2)/N_(2)selectivity(IAST:23-46)and moderate isosteric heats(20-32 kJ/mol).This synthetic strategy is important for the preparation of ultramicroporous carbon microspheres using coal,and the synthetic carbon microspheres have promising prospects for highly efficient CO_(2)capture.

关键词： Coal Ultramicroporous Carbon microspheres Ethanolysis Sequential extraction CO_(2)capture

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan guo Huaiyu Li Hongzhi Zhang Lun Pan chengxiang Shi Kang Xue Xiangwen Zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and *** this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant *** various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were *** properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep *** microstructure of the gel was obtained through scanning electron microscopy *** results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum ***,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure ***,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

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Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao Hao Zhao Shuo-Fei dong Qi guo Jiao-Jiao Xie mei-Ling Lv Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric *** this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample *** compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also *** results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest *** actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward *** was the main exposure pathway for REEs in PM_(2.5)for both children and *** contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and *** exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great *** was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

Novel variants in DNAH6 cause male infertility associated with multiple morphological abnormalities of the sperm flagella(MMAF)and ICSI outcomes

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Asian Journal of Andrology 2024年第1期26卷 91-98页

作者： Zhong-mei Shao Yu-Tong Zhu Meng Gu Sen-Chao guo Hui Yu Kuo-Kuo Li dong-dong Tang Yu-Ping Xu Ming-Rong Lv Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Obstetrics and Gynecology Fuyang Hospital of Anhui Medical UniversityFuyang 236112China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) Hefei 230032China Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People'sRepublicof ChinaHefei 230032China

Variations in the dynein axonemal heavy chain gene,dynein axonemal heavy chain 6(DNAH6),lead to multiple morphological abnormalities of the *** studies have reported that these deficiencies may result in sperm head ***,whether DNAH6 is also involved in human acrosome biogenesis remains *** purpose of this study was to investigate DNAH6 gene variants and their potential functions in the formation of defective sperm heads and ***-exome sequencing was performed on a cohort of 375 patients with asthenoteratozoospermia from the First Affiliated Hospital of Anhui Medical University(Hefei,China).Hematoxylin and eosin staining,scanning electron microscopy,and transmission electron microscopy were performed to analyze the sperm morphology and *** staining and Western blot analysis were conducted to examine the effects of genetic *** identified three novel deleterious variants in DNAH6 among three unrelated *** absence of inner dynein arms and radial spokes was observed in the sperm of patients with DNAH6 ***,deficiencies in the acrosome,abnormal chromatin compaction,and vacuole-containing sperm heads were observed in these patients with DNAH6 *** decreased levels of the component proteins in these defective structures were further confirmed in sperm from patients with DNAH6 variants using Western *** intracytoplasmic sperm injection(ICSl)treatment,the partner of one patient with a DNAH6 variant achieved successful ***,novel variants in DNAH6 genes that contribute to defects in the sperm head and flagella were identified,and the findings indicated Icsl as an effective clinical treatment for such patients.

关键词： asthenoteratospermia DNAH6 intracytoplasmic sperm injection male infertility

A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

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Journal of Arid Land 2024年第9期16卷 1163-1182页

作者： guo Bing XU mei ZHANG Rui LUO Wei School of Civil Engineering and Geomatics Shandong University of TechnologyZibo 255000China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China North China Institute of Aerospace Engineering Langfang 065000China

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade ***,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be ***,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving *** results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River *** 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability *** intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi *** 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of *** gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the *** dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional *** above results could provide decision support for the ecological protection and restoration of the Y

关键词： ecological vulnerability spatio-temporal pattern gravity center migration trajectory interaction factors geodetector green index q-value

Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： Yu-mei Wu Zu-Cheng Chen Qing-guo Huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

Facile synthesis of composite polyferric magnesium-silicate-sulfate coagulant with enhanced performance in water and wastewater

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 574-584页

作者： Xiangtao Huo Rongxia Chai Lizheng Gou mei Zhang Min guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The coagulation process is a widely applied technology in water and wastewater *** composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(SO_(4))_(3),and MgSO_(4) as raw materials in this *** effects of aging time,Fe:Si:Mg,and OH:M molar ratios(M represents the metal ions)on the coagulation performance of the as-pre-pared PFMS were systematically investigated to obtain optimum *** results showed that PFMS coagulant exhibited good co-agulation properties in the treatment of simulated humic acid-kaolin surface water and reactive dye *** the molar ratio was controlled at Fe:Si:Mg=2:2:1 and OH:M=0.32,the obtained PFMS presented excellent stability and a high coagulation *** removal efficiency of ultraviolet UV254 was 99.81%,and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L^(-1).After standing the coagulant for 120 d in the laboratory,the removal efficiency of UV254 and residual turbidity of the surface wa-ter were 88.12%and 0.68 NTU,respectively,which accord with the surface water treatment *** addition,the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron *** with polyferric silicate-sulfate(PFS)and polymagnesium silicate-sulfate(PMS),the PFMS coagulant played a better decolor-ization role within the pH range of 7-13.

关键词： polyferric-magnesium-silicate-sulfate composite coagulants water and wastewater excellent stability high coagulation ef-ficiency decolorization

Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1756-1764页

作者： Jin-You guo Li-Li Zhao Hui-Jun Cai Hui Zeng Wei-dong mei Department of Oncology The Second People's Hospital of Zhejiang Province Taizhou Yuhuan CityTaizhou 317605Zhejiang ProvinceChina Department of Interventional China's Zhejiang Province Tumor HospitalHangzhou 310000Zhejiang ProvinceChina

BACKGROUND The recurrence rate of liver cancer after surgery is *** ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its efficacy in recurrent liver cancer remains *** To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver *** Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan:Control(RFA alone);and experimental[TACE combined with RFA(TACE+RFA)].The incidence of increased alanine aminotransferase levels,complications,and other indices were compared between the two groups before and after the *** One month after the procedures,the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group(P0.05).CONCLUSION TACE+RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function.

关键词： Transcatheter arterial chemoembolization Radiofrequency ablation Recurrent liver cancer Clinical efficacy Overall response rate Disease control rate