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An observed nocturnal ozone transport event in the Sichuan Basin,Southwestern China

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Journal of Environmental Sciences 2024年第4期138卷 10-18页

作者： Ruyue Guo guangming Shi Dan zhang Yang Chen Chao Peng Chongzhi Zhai Fumo Yang Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China College of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China National Engineering Research Center on Flue Gas Desulfurization Chengdu 610065China Chongqing Academy of Eco-Environmental Science Chongqing 401147China Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Key Laboratory for Urban Atmospheric Environment Integrated Observation&Pollution Prevention and Control of Chongqing Chongqing 401147China

The ozone(O_(3))pollution in China drew lots of attention in recent years,and the Sichuan Basin(SCB)was one of the regions confronting worsening O_(3)pollution *** previous studies have shown that regional transport is an important contributor to O_(3)***,very few features of the O_(3)profile during transport have been reported,especially in the border regions between different administrative *** this study,we conducted tethered balloon soundings in SCB during the summer of 2020 and captured a nocturnal O_(3)transport event during the ***,the O_(3)transport occurred in the bottom of the residual layer,between 200 and 500 m above ground ***,the transport pathway was directed from southeast to northwest based on the analysis of the wind field and air mass *** effect of transport in the residual layer on the surface O_(3)concentration was related to the spatial distribution of O_(3).For cities with high O_(3)concentrations in the upwind region,the transport process would bring clean air masses and abate *** downwind lightly polluted cities,the transport process would slow down the decreasing or even increase the surface O_(3)concentration during the *** provided observational facts on the profile features of a transboundary O_(3)transport event between two provincial administrative divisions,which implicated the importance of joint prevention and control ***,the sounding parameters were limited and the quantitative analysis was preliminary,more integrated,and thorough studies of this topic were called for in the future.

关键词： Ozone Sichuan basin Transport event Vertical profile

Mechanical properties and interfacial characteristics of 6061 Al alloy plates fabricated by hot-roll bonding

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1890-1899页

作者： Zongan Luo Xin zhang Zhaosong Liu Hongyu Zhou Mingkun Wang guangming Xie State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

This work aims to investigate the mechanical properties and interfacial characteristics of 6061 Al alloy plates fabricated by hotroll bonding(HRB)based on friction stir *** results showed that ultimate tensile strength and total elongation of the hot-rolled and aged joints increased with the packaging vacuum,and the tensile specimens fractured at the matrix after exceeding 1 ***-equilibrium grain boundaries were formed at the hot-rolled interface,and a large amount of Mg_(2)Si particles were linearly precipitated along the interfacial grain boundaries(IGBs).During subsequent heat treatment,Mg_(2)Si particles dissolved back into the matrix,and Al_(2)O_(3) film remaining at the interface eventually evolved into *** addition,the local IGBs underwent staged elimination during HRB,which facilitated the interface healing due to the fusion of grains at the *** process was achieved by the dissociation,emission,and annihilation of dislocations on the IGBs.

关键词： 6061 Al alloy hot-roll bonding vacuum mechanical properties interfacial grain boundaries

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A fast implementation for computing spatial impulse response of ultrasonic transducers

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Chinese Journal of Acoustics 2016年第3期35卷 212-219页

作者： DONG Ming MA Hongwei zhang guangming CHEN Yuan YANG Ping School of Mechanical Engineering Xi'an University of Science and Technology General Engineering Research Institute Liverpool John Moores University School of Science Xi'an University of Science and Technology National Institute of Metrology

The spatial impulse response（SIR） method is often used as the ＇gold standard5 in simulation of transient acoustic wave fields due to its high accuracy in the linear ***, a high sampling frequency is often required in order to achieve the high accuracy. As a result, a large amount of data has to be processed. In this paper a fast approach for computing spatial impulse response is proposed to reduce the computation burden. The proposed approach is developed by employing the relationship of SIRs at observed points and SIRs of the projection points on the transducer surface. Two critical parameters used in the proposed approach, the calculation sampling frequency and the interpolation sampling frequency, are then *** show that for a 2.25 MHz rectangular transducer with the size of 5 mm×10 mm,a calculation sampling frequency of 1000 MHz and an interpolation sampling frequency of500 MHz can achieve superior performance while improving the computation efficiency 18 times than the direct solving.

关键词： A fast implementation for computing spatial impulse response of ultrasonic transducers

经皮左心耳封堵联合射频消融对持续性心房颤动患者脑钠肽分泌的影响

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国际心血管病杂志 2024年第2期51卷 118-122页

作者：杨婧尤玲王连霞张艳尹磊张光明邢航航谢瑞芹河北医科大学第二医院心内一科石家庄050004

目的:探讨经皮左心耳封堵联合射频消融术对持续性心房颤动(房颤)患者脑钠肽(BNP)分泌的影响。方法:2015年4月至2018年10月连续纳入非瓣膜性持续性房颤患者240例,其中行经皮左心耳封堵联合射频消融术(一站式组)66例,行单纯射频消融术(射... 详细信息

目的:探讨经皮左心耳封堵联合射频消融术对持续性心房颤动(房颤)患者脑钠肽(BNP)分泌的影响。方法:2015年4月至2018年10月连续纳入非瓣膜性持续性房颤患者240例,其中行经皮左心耳封堵联合射频消融术(一站式组)66例,行单纯射频消融术(射频消融组)174例,根据性别、年龄、CHA2DS2-VASc和HAS-BLED评分行倾向性评分1︰1匹配。2组患者在术前,术后1 d、2 d、3 d、3个月、12个月时取静脉血行BNP测定。结果:根据倾向性评分,共入组65对匹配患者。2组患者成功行环肺静脉隔离术,一站式组均成功植入Watchman封堵器,术后患者均转为窦性心律。一站式组患者术后1、2 d时BNP水平较基线明显下降,术后3 d时升高,与术前差异无统计学意义,术后3个月较术前明显下降[(102±138)ng/L对(256±181)ng/L,P<0.001],1年时BNP水平呈持续下降趋势[(66±53)ng/L对(256±181)ng/L,P<0.001]。射频消融组患者的BNP水平也观察到相同的趋势。2组间BNP水平的差异无统计学意义。结论:经皮左心耳封堵联合射频消融显著改善了持续性房颤患者心脏的内分泌功能。

关键词：心房颤动经皮左心耳封堵射频消融脑钠肽

XIAP expression and its predictive significance of prognosis in stage IIB osteosarcomas

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The Chinese-German Journal of Clinical Oncology 2008年第7期7卷 416-419页

作者： Yunfa Yang Hong DU Pin Huang Jianwei Wang guangming zhang Zhonghe Xu Department of Orthopedics Guangzhou First Municipal People＇s Hospital Guangzhou Medical College Guangzhou 510180 China Department of Pathology Guangzhou First Municipal People＇s Hospital Guangzhou Medical College Guangzhou 510180 China Department of Surgery Liwang Hospital Guangzhou Medical College Guangzhou 510180 China

Objective： To evaluate X-linked inhibitor of apoptosis protein （XIAP） expression in biopsy specimens from the patients with stage lib osteosarcomas before chemotherapy to study XIAP expression and its predictive significance of progosis in stage lib osteosarcomas. Methods： The expression of XIAP was retrospectively detected by SP immunohistochem- istry in 31 cases biopsy specimens from stage lib osteosarcomas before chemotherapy, and the relationship between XIAP expression and clinicopathologic features of the patients with stage lib osteosarcomas was analyzed. Results： The osteo- sarcoma specimens showed strong cell nucleus immunoreaction of XIAP while normal bone specimens showed weak. High XIAP positive expression independently predicted the patient＇s poor outcome and had no relationship with clinicopathologic variables such as age, gender, location, tumor size, rate of tumor necrosis to preoperative chemotherapy, local recurrence （P 〉 0.05）. Significant correlations were found between high XIAP expression and metastasis （P -- 0.022）, and also between high XIAP expression and final survival （P = 0.011）. Conclusion： XIAP plays an important role in the development of stage liB osteosarcomas and XIAP expression of biopsy specimens before chemotherapy can be seen as a promising prognostic marker in early predicting the outcome of patients suffering from stage lib osteosarcomas,

关键词： X-linked inhibitor of apoptosis protein (XlAP) osteosarcomas prognosis

Observation of a bi-critical point between antiferromagnetic and superconducting phases in pressurized single crystal Ca0.73La0.27FeAs2

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Science Bulletin 2017年第12期62卷 857-862页

作者： Yazhou Zhou ShanJiang Qi wu Vladimir A.Sidorov Jing Guo Wei Yi Shan zhang Zhe Wang HonghongWang shu Cai Ke Yang Sheng Jiang Aiguo Li Ni Ni guangming zhang Liling Sun Zhongxian Zhao Institute of Physics and Beijing National Laboratory for Condensed Matter Physics Chinese Academy of SciencesBeijing 100190China Department of Physics and Astronomy UCIALos AngelesCA 90095USA Institute for High Pressure Physics Russian Academy of Sciences142190 TroitskMoscowRussia Shanghai Synchrotron Radiation Facilities Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China State Key Laboratory for Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBelting 100084China Collaborative Innovation Center of Quantum Matter Beijing 100190China University of Chinese Academy of Sciences Beijing 100190China

One of the most strikingly universal features of the high-temperature superconductors is that the super- conducting phase emerges in the close proximity of the antiferromagnetic phase, and the interplay between these two phases poses a long-standing challenge. It is commonly believed that, as the antifer- romagnetic transition temperature is continuously suppressed to zero, there appears a quantum critical point, around which the existence of antiferromagnetic fluctuation is responsible for the development of the superconductivity. In contrast to this scenario, we report the observation of a bi-critical point identified at 2,88 GPa and 26.02 K in the pressurized high-quality single crystal Cao.73Lao.27FeAs2 by com- plementary in-situ high pressure measurements. At the critical pressure, we find that the antiferromag- netism suddenly disappears and superconductivity simultaneously emerges at almost the same temperature, and that the external magnetic field suppresses the superconducting transition temperature but hardly affects the antiferromagnetic transition temperature.

关键词： Iron pnictide superconductorBi-critical pointSuperconductivityAntiferromagnetic orderHigh pressure

Impacts of Power Density on Heavy Metal Release During Ultrasonic Sludge Treatment Process

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Chinese Journal of Chemical Engineering 2014年第4期22卷 469-473页

作者：张光明万甜高峰董姗 School of Environment & Natural Resource Renmin University of China State Key Lab of Urban Water Resource and Environment Harbin Institute of Technology

The impact of ultrasonic power density on changes of heavy metals during sludge sonication was inves-tigated. Results showed that ultrasound could release heavy metals from sludge into the supernatant. There existed an effective power density range of 0.8-1.6 W·ml?1 for the release of the total heavy metal; there was little release below 0.8 W·ml?1 and too high power density was adverse to the release. Furthermore, sonication showed selective release of heavy metal from sludge to the supernatant; copper, cadmium and lead were not released by sonication, while arsenic and nickel were released easily and their release ratio could reach 40%. The effective energy range for each heavy metal was also different that 0.8-1.2 W·ml?1 for arsenic, 0.5-1.6 W·ml?1 for nickel, and 0.8-1.6 W·ml?1 for mercury and chrome. The differences among heavy metal release during sonication might be explained by the different distribution of chemical fractions of each metal in sludge. Such selectivity could be used to control heavy metal release during sludge treatment.

关键词： activated sludge sonication metals power density chemical fractions

Effects of projectile parameters on the momentum transfer and projectile melting during hypervelocity impact

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Defence Technology（防务技术） 2024年第2期32卷 89-103页

作者： Wenjin Liu Qingming zhang Renrong Long Zizheng Gong Ren Jiankang Xin Hu Siyuan Ren Qiang Wu guangming Song State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Spacecraft Environment Engineering China Academy of Space TechnologyBeijing100094China

The effects of projectile/target impedance matching and projectile shape on energy,momentum transfer and projectile melting during collisions are investigated by numerical *** comparing the computation results with the experimental results,the correctness of the calculation and the statistical method of momentum transfer coefficient is *** shapes of aluminum,copper and heavy tungsten alloy projectiles striking aluminum,basalt,and pumice target for impacts up to 10 km/s are *** influence mechanism of the shape of the projectile and projectile/target density on the momentum transfer was *** an increase in projectile density and length-diameter ratio,the energy transfer time between the projectile and targets is *** projectile decelerates slowly,resulting in a larger cratering *** energy consumed by the projectile in the excavation stage increased,resulting in lower mass-velocity of ejecta and momentum transfer *** numerical simulation results demonstrated that for different projectile/target combinations,the higher the wave impedance of the projectile,the higher the initial phase transition velocity and the smaller the mass of phase *** results can provide theoretical guidance for kinetic impactor design and material selection.

关键词： Hypervelocity impact Energy partitioning Impact melting Momentum transfer

骨盆辅助式机器人训练对急性期脑梗死患者步行与躯干控制功能的影响

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机器人外科学杂志（中英文） 2024年第4期5卷 564-567,574页

作者：王卫国杨延辉张光明邢小桐赵欣贻曹乾陕西省康复医院神经康复科陕西西安710065 陕西省康复医院物理因子疗法科陕西西安710065

目的:探讨骨盆辅助式机器人训练对急性期脑梗死患者步行与躯干控制功能的影响。方法:前瞻性研究2020年5月—2023年4月陕西省康复医院收治的216例急性期脑梗死患者临床资料,根据随机数字表法分为对照组(n=108,采用常规训练)和研究组(n=1... 详细信息

目的:探讨骨盆辅助式机器人训练对急性期脑梗死患者步行与躯干控制功能的影响。方法:前瞻性研究2020年5月—2023年4月陕西省康复医院收治的216例急性期脑梗死患者临床资料,根据随机数字表法分为对照组(n=108,采用常规训练)和研究组(n=108,采用骨盆辅助式机器人训练)。比较两组患者的步行功能、步态参数、平衡功能和躯干控制功能。结果:与训练前相比,训练2个月后两组患者功能性步行量表(FAC)分级更优,差异具有统计学意义(P<0.05);与对照组比较,研究组训练2个月后的FAC分级更优,差异具有统计学意义(P<0.05)。与训练前比较,训练2个月后两组患者步态参数更优,差异具有统计学意义(P<0.05);与对照组比较,研究组训练2个月后患者步态参数更优,差异具有统计学意义(P<0.05)。与训练前比较,训练2个月后两组Berg平衡量表(BBS)和躯干控制能力测试(TCT)评分均升高,差异具有统计学意义(P<0.05);与对照组比较,研究组训练2个月后BBS评分和TCT评分更高,差异具有统计学意义(P<0.05)。结论:骨盆辅助式机器人训练可改善急性期脑梗死患者步行功能、平衡功能和躯干控制功能。

关键词：骨盆辅助式机器人脑梗死急性期步行功能躯干控制功能

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