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A large-scale cold plasma jet: generation mechanism and application effect

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Plasma Science and Technology 2024年第4期26卷 1-8页

作者：崔伟胜张若兵 Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055People’s Republic of China

atmospheric pressure cold plasma jets(APCPJs) typically exhibit a slender, conical structure,which imposes limitations on their application for surface modification due to the restricted treatment area. In this paper, we introduce a novel plasma jet morphology known as the large-scale cold plasma jet(LSCPJ), characterized by the presence of both a central conical plasma jet and a peripheral trumpet-like diffuse plasma jet. The experimental investigations have identified the factors influencing the conical and the trumpet-like diffuse plasma jet, and theoretical simulations have shed light on the role of the flow field and the electric field in shaping the formation of the LSCPJ. It is proved that, under conditions of elevated helium concentration, the distributions of impurity gas particles and the electric field jointly determine the plasma jet’s morphology. High-speed ICCD camera images confirm the dynamic behavior of plasma bullets in LSCPJ, which is consistent with the theoretical analysis. Finally, it is demonstrated that when applied to the surface treatment of silicone rubber, LSCPJ can achieve a treatment area over 28 times larger than that of APCPJ under equivalent conditions. This paper uncovers the crucial role of impurity gases and electric fields in shaping plasma jet morphology and opens up the possibility of efficiently diversifying plasma jet generation effects through external electromagnetic fields. These insights hold the promise of reducing the generation cost of plasma jets and expanding their applications across various industrial sectors.

关键词： diffuse plasma jet flow field electric field surface treatment

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

Computational properties of a new horizontal staggered grid

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Science china Earth sciences 2005年第9期48卷 1559-1568页

作者： LIU YudiState key laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china Institute of Meteorology, PLA university of Science and Technology, Nanjing 211101, china State key laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Ph Chinese Academy of Sciences Beijing China Institute of Meteorology PLA University of Science and Technology Nanjing China

This paper presents a new horizontal staggered grid (LE grid), which defines h at a gridpoint, and both u and v at the same mid-gridpoint along the x and y directions. A general method is used to deduce the dispersion relationships of describing inertia gravity waves on LE grid and Arakawa A―E grids, which are then compared with the analytical solution (AS) in re- solved or under-resolved cases, using two-order central difference or four-order compact differ- ence scheme from the frequency and group velocity. Results show that in both resolved and under-resolved cases, no matter whether two-order central difference or four-order compact dif- ference scheme is used, the frequency and group velocity discrete errors on LE grid in describing inertia gravity waves are smaller than those of Arakawa A―E grids. At the same time, it is only on LE or Arakawa grid C that the employment of a compact difference scheme of higher difference precision can improve their accuracy in describing inertia gravity waves. However, as for the other four grids (Arakawa A,B,D and E), when the difference precision increases, the accuracy of simulating inertia gravity waves decreases.

关键词： horizontal staggered grid, inertia gravity wave, LE grid, Arakawa A-E grid, compact difference scheme, central difference.

Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2018-2022

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Advances in Climate Change Research 2024年第2期15卷 297-311页

作者： Yu-Long KANG Shi-Chang KANG Wan-Qin GUO Tao CHE Zong-Li JIANG Zhen-Feng wang Qiang-Qiang XU Cheng-De yang State key laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China university of Chinese Academy of sciences Beijing 100083China key laboratory of Remote Sensing of gansu province Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Earth sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

Ice sheet serves as a crucial indicator for assessing climate *** loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface ***,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal *** study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2 satellites during *** results indicate that the glacier area reduced by approximately 166.1±44.2 km^(2)(-0.2%±0.1%per year)during the study period,with an acceleration after 2020(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern *** maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2021 were the highest(exceeded 4210 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing *** glacier G012158E47018N,McNeile Glacier,glacier G299637E64094S and Drygalski Glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their *** results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere ***,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios.

关键词： Glacier area Seasonal ice speed Sentinel 1&2 Northern Antarctic Peninsula Ice-ocean-atmosphere processes

OXIDATIVE COUPLING OF METHANE OVER Mn2O3-Na2WO4/SiO2 CATALYST IN THE ABSENCE OF DILUTE GAS

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Journal of Energy Chemistry 1995年第3期 337-343页

作者： WU Jin-Gang LI Shu-BenState key laboratory of Oxo Synthesis and Selective Oxidation lanzhou Institute of Chemical Physics, Academia Sinica lanzhou, gansu 730000

The oxidative coupling of methane over Mn2O3-Na2WO4/SiO2 catalyst has been investigated in the absence of dilute gas. 16.4% of C2 yield and 80.4% of the selectivity to C2 hydrocarbons were obtained at CH4/O2 = 8.5/1.5. The effect of flow rate on the selectivity to C2 hydrocarbons and CH4 conversion was different under the reaction condition of different ratio of CH4 to oxygen. The flow rate had a more remarkable effect on the selectivity at the lower ratio of methane to oxygen. The addition of steam into the reaction gas can increase C2 yield to some extent, but that of HC1 decrease the selectivity to C2 hydrocarbons.

关键词： oxidative coupling of methane Mn2O3-Na2WO4/SiO2 no dilute gas

Safety of high-carbohydrate fluid diet 2 h versus overnight fasting before non-emergency endoscopic retrograde cholangiopancreatography:A single-blind,multicenter,randomized controlled trial

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Chinese Medical Journal 2024年第12期137卷 1437-1446页

作者： Wenbo Meng Joseph W.Leung Zhenyu wang Qiyong Li Leida Zhang Kai Zhang Xuefeng wang Meng wang Qi wang Yingmei Shao Jijun Zhang Ping Yue Lei Zhang Kexiang Zhu Xiaoliang Zhu Hui Zhang Senlin Hou Kailin Cai Hao Sun Ping Xue Wei Liu Haiping wang Li Zhang Songming Ding Zhiqing yang Ming Zhang Hao Weng QingyuanWu Bendong Chen Tiemin Jiang Yingkai wang Lichao Zhang Ke Wu Xue yang Zilong Wen Chun Liu LongMiao Zhengfeng wang Jiajia Li Xiaowen Yan Fangzhao wang Lingen Zhang Mingzhen Bai Ningning Mi XianzhuoZhang Wence Zhou Jinqiu Yuan Azumi Suzuki Kiyohito Tanaka Jiankang Liu Ula Nur Elisabete Weiderpass Xun Li Department of General Surgery The First Hospital of Lanzhou UniversityLanzhouGansu 730000China key laboratory of Biological Therapy and Regenerative Medicine Transformation gansu province LanzhouGansu 730000China Division of Gastroenterology and Hepatology UC Davis Medical CenterSacramentoCA 95816USA Department of Minimally Invasive Surgery Tianjin Nankai HospitalTianjin 300100China Division of Hepatobiliary and Pancreatic Surgery Department of SurgeryShulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren UniversityHangzhouZhejiang 310000China Department of Hepatobiliary Surgery Southwest HospitalArmy Medical UniversityChongqing 400000China Hepatobiliary Surgery Department Shandong Provincial Third HospitalJinanShandong 250000China Department of General Surgery Xinhua HospitalAffiliated to Shanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Biliary Tract Disease ResearchShanghai 200000China Department of Hepatobiliary and Pancreatic Surgery The First Hospital of Jilin UniversityChangchunJilin 130000China Department of Hepatobiliary Surgery The General Hospital of Ningxia Medical UniversityYinchuanNingxia 750000China Department of Hepatobiliary&Hydatid Digestive and Vascular Surgery CenterXinjiang Key Laboratory of Echinococcosis and Liver Surgery ResearchThe First Affiliated Hospital of Xinjiang Medical UniversityUrumqiXinjiang 830000China Department of Hepatobiliary and Pancreatic Surgery The First Hospital of Shanxi Medical UniversityTaiyuanShanxi 030000China Department of General Surgery The Second Hospital of Lanzhou UniversityLanzhouGansu 730000China Department of Biliopancreatic Endoscopic Surgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei 050000China Gastrointestinal Surgery Department Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430000China Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710000China Depart

Background:Although overnight fasting is recommended prior to endoscopic retrograde cholangiopancreatography(ERCP),the benefits and safety of high-carbohydrate fluid diet(CFD)intake 2 h before ERCP remain *** study aimed to analyze whether high-CFD intake 2 h before ERCP can be safe and accelerate patients’***:This prospective,multicenter,randomized controlled trial involved 15 tertiary ERCP centers.A total of 1330 patients were randomized into CFD group(n=665)and fasting group(n=665).The CFD group received 400 mL of maltodextrin orally 2 h before ERCP,while the control group abstained from food/water overnight(>6 h)before *** ERCP procedures were performed using deep sedation with intravenous *** investigators were blinded but not the *** primary outcomes included postoperative fatigue and abdominal pain score,and the secondary outcomes included complications and changes in metabolic *** outcomes were analyzed according to a modified intention-to-treat ***:The post-ERCP fatigue scores were significantly lower at 4 h(4.1±2.6 vs.4.8±2.8,t=4.23,Preduction in post-ERCP fatigue,

关键词： Endoscopic retrograde cholangiopancreatography ERCP Carbohydrate Fasting Safety Complications Enhanced recovery after surgery Randomized controlled trial

A general climatology of categorized Martian ionospheric irregularities

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Science china Earth sciences 2024年

作者： Xin WAN Jiahao ZHONG Yongqiang HAO Chao XIONG Hui wang Yutian CAO Jun cui Yiwen LIU Qiaoling LI Jiawei KUAI Planetary Environmental and Astrobiological Research laboratory (PEARL) School of Atmospheric Sciences Sun Yat-sen University key laboratory of Tropical Atmosphere-Ocean System Ministry of Education Department of Space Physics College of Electronic Information Luojia Laboratory Wuhan University School of Physics and Electronic Information Shangrao Normal University School of Petroleum China University of Petroleum-Beijing at Karamay college of Astronautics Nanjing University of Aeronautics and Astronautics

A climatological survey of Martian ionospheric plasma density irregularities was conducted by exploring the in-situ measurements of the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. The irregularities were first classified as enhancement, depletion, and oscillation. By checking the simultaneous magnetic field fluctuation, the irregularities have been classified into two types:with or without magnetic signatures. The classified irregularities exhibit diverse global occurrence patterns, as those with magnetic signatures tend to appear near the periphery of the crustal magnetic anomaly (MA), and those without magnetic signatures prefer to appear either inside of the MA or outside of the MA, depending on the type and solar zenith angle. Under most circumstances, the irregularities have a considerable occurrence rate at altitudes above the ionospheric dynamo height (above 200 km), and the magnetization state of the ions seems irrelevant to their occurrence. In addition, the irregularities do not show dependence on magnetic field geometry, except that the enhancement without magnetic signatures favors the vertical field line, implying its equivalence to the localized bulge. Other similarities and discrepancies exist in reference to previous studies. We believe this global survey complements previous research and provides crucial research clues for future efforts to clarify the nature of the Martian ionospheric irregularities.

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OXIDATIVE COUPLING OF METHANE OVER Co2O3-Na2B4O7/SiO2 CATALYST DOPED WITH SODIUM CHLORIDE

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Journal of Energy Chemistry 1994年第3期 306-311页

作者： WU Jin-Gang LI Shu-BenState key laboratory of Oxo Synthesis and Selective Oxidation lanzhou Institute of Chemical Physics, Academia Smca lanzhou, gansu 730000

Alkali chloride-doped transition metal（Co） oxide Pnduced ethyleneselectively in oxidative coupling of *** effect of the content of thecomponent,the preparative method and the calcination time on Cyield hasbeen investigated for NaCl-CoO-NaBO/*** ratio of ethyleneto ethane decreases with the prolonged *** deactivation of the cat-alyst has simply been investigated with XRD spectrum.

关键词： SiO Co IT Na OXIDATIVE COUPLING OF METHANE OVER Co2O3-Na2B4O7/SiO2 CATALYST DOPED WITH SODIUM CHLORIDE

Mechanisms of Apigenin-7-glucoside As a Hepatoprotective Agent

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Biomedical and Environmental sciences 2005年第1期18卷 65-70页

作者： QIU-SHENGZHENG XI-LINGSUN BoXU GANGLI MENGSONG Departmentofbiochemistry YantaiUniversityYantaiShandong264005China InstituteofBiophysics SchoolofLifeSciencesLanzhouUniversityLanzhouGansu730000China HospitalofBaiyinCity BaiyinGansu730900China.

Ixeris chinesis (Thunb.) Ankai has been used as a Chinese folk medicine, but only scanty information is available on the physiological and biochemical functions of the compounds extracted from I. chinesis. In the present study the effects of apigenin -7-glucoside (APIG) isolated from I. chinesis against liver injury caused by carbon tetrachloride (CCl4) were investigated. Methods The contents of malondialdehyde (MDA), glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), and reduced glutathione (GSH) were evaluated by spectrophotography. The content of 8-Hydroxydeoxyguanosine (8-OHdG) was measured with high-performance liquid chromatography (HPLC) equipped with electrochemical and UV detection methods. The antioxidant activity of APIG was evaluated using chemiluminescence single photon counting technology. Results CCl4 significantly increased the enzyme activities of GPT and GOT in blood serum, as well as the level of MDA and 8-OHdG in liver tissue, and decreased the levels of GSH. Pretreatment with APIG was able not only to suppress the elevation of GPT, GOT, MDA and 8-OHdG, and inhibit the reduction of GSH in a dose-dependent manner in vivo, but also to reduce the damage of hepatocytes in vitro. On the other hand, we also found that APIG had strong antioxidant activity against reactive oxygen species (ROS) in vitro in a concentration-dependent manner. Conclusion The hepatoprotective activity of APIG is possibly due to its antioxidant properties, acting as scavengers of ROS. These results obtained in vivo and in vitro suggest that APIG has protective effects against hepatic oxidative injury induced by chemicals. Further studies on the pharmaceutical functions and immunological responses of APIG may help its clinical application.

关键词： Apigenin-7-glucoside Malondialdehyde Glutathione 8-Hydroxydeoxyguanosine Hepatotoxicity