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Time-domain dynamic constitutive model suitable for mucky soil site seismic response

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： Dong qing Chen su Jin Liguo Zhou Zhenghua Li Xiaojun Architectural Engineering Institute Huaiyin Institute of TechnologyHuai’an 223600China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China Institute of Geophysics China Earthquake AdministrationBeijing 100089China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic response.This study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton curve.By integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics problem.Based on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of sites.At the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear method.The results verify the rationality of the new soil dynamic constitutive model.It can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty soil.The hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

High performance and stable pure-blue quasi-2D perovskite light-emitting diodes by multifunctional zwitterionic passivation engineering

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Advanced Photonics 2024年第2期6卷 32-40页

作者： Chao Shen Shuyan Fang Jibin Zhang Xiangfei Liang Chenhui su Jian qing Wanzhu Cai Yunhan Luo Renqiang yang Lintao Hou Jinan University College of Physics and Optical EngineeringGuangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsGuangzhou Key Laboratory of Vacuum Coating Technologies and New Energy MaterialsGuangzhouChina Jinan University College of Physics and Optical EngineeringGuangdong Provincial Key Laboratory of Optical Fiber Sensing and CommunicationsGuangzhouChina Zhengzhou University School of Physics and MicroelectronicsKey Laboratory of Materials Physics of Ministry of EducationZhengzhouChina Jinan University Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education InstitutesGuangzhouChina Jianghan University School of Optoelectronic Materials and TechnologyKey Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of EducationWuhanChina

Despite the rapid advances of red and green perovskite light-emitting diodes(Pe LEDs),achieving high brightness with high external quantum efficiency(EQE)remains a challenge for the pure-blue Pe LEDs,which greatly hinders their practical applications,such as white-light illumination and in optical communication as a high-speed and low-loss light source.Herein,we report a high-performance pure-blue Pe LED based on mixed-halide quasi-2D perovskites incorporated with a zwitterionic molecule of 3-(benzyldimethylammonio)propanesulfonate(3-BAS).Experimental and density functional theory analysis reveals that 3-BAS can simultaneously eliminate non-radiative recombination loss,suppress halide migration,and regulate phase distribution for smoothing energy transfer in the mixed-halide quasi-2D perovskites,leading to the final perovskites with high photoluminescence quantum yield and robust spectrum stability.Thus,the highperformance pure-blue Pe LED with a recorded brightness with 1806 cd m-2and a relative higher EQE of 9.25%is achieved,which is successfully demonstrated in a visible light communication system for voice signal transmission.We pave the way for achieving highly efficient pure-blue Pe LEDs with great application potential in future optical communication networks.

关键词： pure-blue PeLEDs quasi-2D perovskite zwitterionic additive visible light communication

Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao San-Gang Li Rong-Rong su Li yang Ming-Zhe Liu qing-Yue Xue Shan Liao Zhi Zhou qing-Shan Tan Xian-Guo Tuo Yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization chamber.This system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement results.Testing conducted under normal temperature conditions has demonstrated the system's high precision performance.However,it was observed that temperature variations can affect the measurement performance.Data were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this issue.The feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature correction.The research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

Design and synthesis of polyoxovanadate-based framework for efficient dye degradation

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Tungsten 2024年第2期6卷 447-453页

作者： qing Lan su-Juan Jin Zheng Wang Xu-yang Li Yan Xiong Zhuo-Cheng Wang Shan-Shan Liu Zhi-Ming Zhang Qiang Zhao Engineering Technology Research Center of Henan Province for Solar Catalysis School of Chemical and Pharmaceutical EngineeringNanyang Normal UniversityNanyang 473061China Institute of New Energy Materials&Low Carbon Technology Tianjin University of TechnologyTianjin 300384China

A new polyoxovanadate-based framework material[Cu(en)_(2)]_(4)V_(18)O_(42)(H_(2)O)·6H_(2)O(1)was designed and synthesized by hydrothermal reaction of NaVO_(3),Cu(NO_(3))_(2)·6H_(2)O and 1,2-diaminoethane(en)via carefully adjusting the pH value of the reaction system.The structure of the title compound has been determined by single-crystal X-ray diff raction analysis,thermogravimetric analysis,infrared spectra and elemental analysis.Detail structural analysis demonstrate the three-dimensional(3D)framework structure of compound 1,which was composed of the[V_(18)O_(42)(H_(2)O)]_(8)−({V_(18)O_(42)(H_(2)O)})anions linked by the Cu^(2+)cations.Compound 1 represents the fi rst 3D framework based on{V_(18)O_(42)(H_(2)O)}polyoxoanions and copper complexes.Solar-driven degradation of residual organic pollutants in industrial wastewater is still a major problem for human beings.Photocatalytic experiments reveal that compound 1 possesses of excellent photocatalytic activity for the degradation of methylene blue and rhodamine B.

关键词： Polyoxovanadate Framework Polyoxovanadate-based framework Photocatalytic Organic pollutants

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and properties.Functionally graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co elements.The effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were studied.The as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of elements.The mechanical properties and magnetic properties of the compositionally graded sample show a gradient variation.With the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample decreases.The optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder metallurgy.LPBF in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

Amorphous Sb/C composite with isotropic expansion property as an ultra-stable and high-rate anode for lithium-ion batteries

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Rare Metals 2024年第5期43卷 2039-2052页

作者： Ze-Zhou yang Cheng-Yi Zhang Yu-qing Ou Zhi-Kang su Yan Zhao Heng-Jiang Cong Xin-Ping Ai Jiang-Feng Qian Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular Sciences Wuhan University Institute of Technological Sciences Wuhan University

Antimony （Sb） is an intriguing anode material for Li-ion batteries （LIBs） owing to its high theoretical capacity of 660 m Ah·g-1and appropriate working potential of～0.8 V （vs.Li+/Li）.However,just like all alloying materials,the Sb anode suffers from huge volume expansion （230%） during repeated insertion/extraction of Li+ions,resulting in structural deterioration and rapid capacity decay.In this work,a novel amorphous Sb/C composite with atomically dispersed Sb particles in carbon matrix is prepared via a straightforward high-energy ball milling approach.The intimate intermixing of amorphous Sb with C provides homogeneous element distribution and isotropic volume expansion during cycling,resulting in persistent structural stability.Meanwhile,the disordered structure of amorphous material shortens the diffusion distance of lithium ions/electrons,promoting fast reaction kinetics and rate capability.Benefiting from the aforementioned effects,the amorphous Sb/C exhibits a high reversible capacity of537.4 m Ah·g-1at 0.1 A·g-1and retains 201.0 m Ah·g-1at an ultrahigh current rate of 10.0 A·g-1.Even after 1500deep cycles at 2.0 A·g-1,the amorphous Sb/C electrode still maintains 86.3%of its initial capacity,which outperforms all existing Sb-based anodes reported so far.Postmortem analysis further reveals a greatly reduced volume variation of merely 34.6%for the amorphous Sb/C electrode,much lower than that of 223.1%for crystalline Sb materials.This study presents a new approach to stabilizing Sb-based alloy anodes and contributes to the construction of high-performance amorphous anode materials for LIBs,enabling advanced energy storage.

关键词： Amorphous Sb/C anode Homogeneous element distribution Isotropic volume expansion Ultra-long cycle stability High-rate capability Lithium-ion battery

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-qing Li Wen-Hao Wang Yuan-Da su Jun-Xin Guo Xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic scale.Hence,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the fractures.Using Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and SV-waves.We then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy approximation.The results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave velocities.The coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV waves.Randomly oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV waves.Through a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Delivery room resuscitation intensity and associated neonatal outcomes of 24^(+0)-31^(+6) weeks'preterm infants in China:a retrospective cross-sectional study

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World Journal of Pediatrics 2024年第1期20卷 64-72页

作者： Si-Lu Wang Chun Chen Xin-Yue Gu Zhao-qing Yin Le su Si-Yuan Jiang Yun Cao Li-Zhong Du Jian-Hua sun Jiang-Qin Liu Chuan-Zhong yang Department of Neonatology Shanghai Key Laboratory of Maternal Fetal MedicineShanghai Institute of Maternal-Fetal Medicine and Gynecologic OncologyShanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityNo.2699Gaoke Western RoadPudong DistrictShanghai 201204China Department of Neonatology Affiliated Shenzhen Maternity and Child Healthcare HospitalSouthern Medical UniversityNo.2004Hongli RoadFutian DistrictShenzhen 518028China NHC Key Laboratory of Neonatal Diseases Fudan UniversityChildren's Hospital of Fudan UniversityShanghaiChina Department of Neonatology People's Hospital of DehongKunming Medical UniversityDehongChina Department of Neonatology Children's Hospital of Fudan UniversityShanghaiChina Department of Neonatology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of Neonatology Shanghai Children's Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Background The aim of this study was to review current delivery room(DR)resuscitation intensity in Chinese tertiary neonatal intensive care units and to investigate the association between DR resuscitation intensity and short-term outcomes in preterm infants born at 24+0_31+6 weeks gestation age(GA).Methods This was a retrospective cross-sectional study.The source population was infants born at 24+0_31+6 weeks'GA who were enrolled in the Chinese Neonatal Network 2019 cohort.Eligible infants were categorized into five groups:(1)regular care;(2)oxygen supplementation and/or continuous positive airway pressure(O2/CPAP);(3)mask ventilation;(4)endotracheal intubation;and(5)cardiopulmonary resuscitation(CPR).The association between DR resuscitation and shortterm outcomes was evaluated by inverse propensity score-weighted logistic regression.Results Of 7939 infants included in this cohort,2419(30.5%)received regular care,1994(25.1%)received O,/CPAP,1436(18.1%)received mask ventilation,1769(22.3%)received endotracheal intubation,and 321(4.0%)received CPR in the DR.Advanced maternal age and maternal hypertension correlated with a higher need for resuscitation,and antenatal steroid use tended to be associated with a lower need for resuscitation(Psuscitation in DR after adjusting for perinatal factors.Resuscitation strategies vary widely between centers,with over 50%of preterm infants in eight centers requiring higher intensity resuscitation.Conclusions Increased intensity of DR interventions was associated with increased mortality and morbidities in very preterm infants in China.There is wide variation in resuscitative approaches across delivery centers,and ongoing quality improvement to standardize resuscitation practices is needed.

关键词： Cardiopulmonary resuscitation Delivery room Endotracheal intubation Neonatal resuscitation Preterm

Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China

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World Journal of Gastroenterology 2024年第10期30卷 1346-1357页

作者： Jing-Feng Chen Zhuo-qing Wu Hao-Shuang Liu su Yan You-Xiang Wang Miao Xing Xiao-Qin Song su-Ying Ding Health Management Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Institute of Systems Engineering Dalian University of TechnologyDalian 116024Liaoning ProvinceChina College of Public Health Zhengzhou UniversityZhengzhou 450001Henan ProvinceChina School of Basic Medicine and Forensic Medicine Henan University of Science and TechnologyLuoyang 471003Henan ProvinceChina

BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.REsuLTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD.

关键词： Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study