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Simulating the Escaping Atmosphere of GJ 436 b with Two-fluid Magnetohydrodynamic Models
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作者 Lei Xing Jianheng Guo +1 位作者 Chuyuan Yang Dongdong Yan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期273-286,共14页
Observations of transmission spectra reveal that hot Jupiters and Neptunes are likely to possess escaping atmospheres driven by stellar radiation.Numerous models predict that magnetic fields may exert significant infl... Observations of transmission spectra reveal that hot Jupiters and Neptunes are likely to possess escaping atmospheres driven by stellar radiation.Numerous models predict that magnetic fields may exert significant influences on the atmospheres of hot planets.Generally,the escaping atmospheres are not entirely ionized,and magnetic fields only directly affect the escape of ionized components within them.Considering the chemical reactions between ionized components and neutral atoms,as well as collision processes,magnetic fields indirectly impact the escape of neutral atoms,thereby influencing the detection signals of planetary atmospheres in transmission spectra.In order to simulate this process,we developed a magnetohydrodynamic multi-fluid model based on MHD code PLUTO.As an initial exploration,we investigated the impact of magnetic fields on the decoupling of H^(+)and H in the escaping atmosphere of the hot Neptune GJ436b.Due to the strong resonant interactions between H and H^(+),the coupling between them is tight even if the magnetic field is strong.Of course,alternatively,our work also suggests that merging H and H^(+)into a single flow can be a reasonable assumption in MHD simulations of escaping atmospheres.However,our simulation results indicate that under the influence of magnetic fields,there are noticeable regional differences in the decoupling of H^(+)and H.With the increase of magnetic field strength,the degree of decoupling also increases.For heavier particles such as O,the decoupling between O and H^(+)is more pronounced.Our findings provide important insights for future studies on the decoupling processes of heavy atoms in the escaping atmospheres of hot Jupiters and hot Neptunes under the influence of magnetic fields. 展开更多
关键词 magnetohydrodynamics(MHD) planets and satellites:atmospheres HYDRODYNAMICS
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Impact of Exercise Atmosphere on Adolescents’Exercise Behavior:Chain Mediating Effect of Exercise Identity and Exercise Habit
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作者 Zhen Su Ziqiang Zhang Yonghao Zhou 《International Journal of Mental Health Promotion》 2024年第7期579-588,共10页
Appropriate physical exercise has a positive impact on adolescents’physical and mental health,but there is a serious lack of physical exercise among Chinese adolescents.How to shape their exercise behavior(EB)has bec... Appropriate physical exercise has a positive impact on adolescents’physical and mental health,but there is a serious lack of physical exercise among Chinese adolescents.How to shape their exercise behavior(EB)has become an important task in promoting their development.A questionnaire survey was conducted using stratified cluster random sampling on three middle schools by class in Zhejiang Province,China to investigate the impact of exercise atmosphere(EA)on adolescents’exercise behavior and the mediating role of exercise identity(EI)and exercise habit(EH).806 adolescents were investigated by the Exercise Atmosphere Scale(EAS),Exercise-Identity Scale(EIS),Self-Report Habit Index(SRHI),and Physical Activity Rating Scale(PARS-3).The results show that:There is a significant positive correlation between each two of exercise atmosphere,exercise identity,exercise habit,and exercise behavior(p<0.05).Exercise atmosphere could not only directly affect adolescents’physical exercise behavior but can also indirectly affect their physical exercise behavior through the mediating effect of exercise identity and exercise habit,involving three mediating pathways,namely,the mediating path through exercise identity,the mediating pathway through exercise habit and the chain mediating pathway through exercise identity and exercise habit.The direct effect of exercise atmosphere on exercise behavior was 0.459(p<0.01),accounting for 62.62% of the total effect of 0.733,and its indirect effect was 0.274,accounting for 37.28% of the total effect.To a certain extent,the mediating effect model reveals the mechanism of exercise atmosphere affecting exercise behavior and has a certain reference value for promoting adolescents’exercise behavior.We should start by creating an exercise atmosphere,cultivating exercise identity,and enhancing exercise habits to help teenagers form active physical exercise behaviors. 展开更多
关键词 Exercise atmosphere exercise identity exercise habit exercise behavior
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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan Zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang Ping Zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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Investigating the Creation of Cultural Atmospheres in Physical Bookstores Within the Context of Scene-Based Consumption:A Perspective Based on the Ways of Seeing
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作者 Chai Dongdong He Jiani 《Contemporary Social Sciences》 2024年第3期92-105,共14页
In an era of scene-based consumption,the essence of operating a bookstore lies in accepting and enabling the bookstore to play its role as a cultural medium for browsing and appreciating books,which in turn fosters th... In an era of scene-based consumption,the essence of operating a bookstore lies in accepting and enabling the bookstore to play its role as a cultural medium for browsing and appreciating books,which in turn fosters the development of a distinctive bookstore culture.This new type of consumption context has led to an evolution in the book-reading culture in physical bookstores that is characterized by a shift from a paradigm of passive reading to one where the emphasis is on interactive viewing.This transition has laid the foundation for the creation of cultural atmospheres in bookstores,and it highlights the visual interactions that now exist between readers and books as well as with other related cultural industries.The dominant and fundamental logic behind this process is symbiosis,experience,aesthetics,immersion,and creativity.However,when a form of culture that focuses on consumption-oriented browsing begins to overshadow knowledge acquisition during the process of book reading,the cultural essence of bookstores is likely to be diminished.Therefore,the cultural essence within the scene-based consumption context should be enhanced by creating innovative viewing activities that showcase the cultural and emotional implications inherent in the scene itself,and thus help to align the identity of the bookstore with its in-situ cultural space. 展开更多
关键词 physical bookstores bookstore culture scene-based viewing scene-based consumption the creation of cultural atmospheres
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Analysis of quality-related proteins in golden pompano(Trachinotus ovatus)fillets with modified atmosphere packaging under superchilling storage
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作者 Chuang Pan Xiaofan Zhang +4 位作者 Shengjun Chen Yong Xue Yanyan Wu Yueqi Wang Di Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2253-2265,共13页
Here,we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage.Tandem mass tags(TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between pr... Here,we aimed to study the changes in proteome of golden pompano fillets during post-mortem storage.Tandem mass tags(TMT)-labeled quantitative proteomic strategy was applied to investigate the relationships between protein changes and quality characteristics of modified atmosphere packaging(MAP)fillets during superchilling(-3°C)storage.Scanning electron microscopy was used to show that the muscle histology microstructure of fillets was damaged to varying degrees,and low-field nuclear magnetic resonance was used to find that the immobilized water and free water in the muscle of fillets changed significantly.Total sulfhydryl content,TCA-soluble peptides and Ca2+-ATPase activity also showed that the fillet protein had a deterioration by oxidation and denaturation.The Fresh(FS),MAP,and air packaging(AP)groups were set.Total of 150 proteins were identified as differential abundant proteins(DAPs)in MAP/FS,while 209 DAPs were in AP/FS group.The KEGG pathway analysis indicated that most DAPs were involved in binding proteins and protein turnover.Correlation analysis found that 52 DAPs were correlated with quality traits.Among them,8 highly correlated DAPs are expected to be used as potential quality markers for protein oxidation and water-holding capacity.These results provide a further understanding of the muscle deterioration mechanism of packaging golden pompano fillets during superchilling. 展开更多
关键词 Tandem mass tags(TMT)proteomics Trachinotus ovatus Modified atmosphere packaging Superchilling storage Low-field nuclear magnetic resonance Protein deterioration
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High temperature oxidation of inoculated high Si/SiMo ductile cast irons in air and combustion atmospheres
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作者 Iuliana Stan Mihai Chisamera +5 位作者 Robert Lascu Codrut Cariga Eduard Stefan Stelian Stan Denisa Anca Iulian Riposan 《China Foundry》 SCIE EI CAS CSCD 2024年第5期555-562,共8页
The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry ... The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating temperature.The weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible influence.At the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°C.The alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast iron.Positive effects of inoculating elements increase with the heating temperature,with Ca and Ba-FeSi inoculation generally showing better performance.Irons inoculated with CaRE-FeSi exhibit a higher degree of oxidation.These results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-Si ductile irons.As the lower compactness degree is typical for graphite nodules in high-Si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule quality.Inoculation,in particular,is a potential method to achieve this improvement. 展开更多
关键词 ductile iron spheroidal graphite Si/SiMo oxidation air/combustion atmospheres FeSiCaMgRE treatment Ca Ca-Ba Ca-RE inoculation structure characteristics
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Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique
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作者 Xiaoxue Wang Lulu Jin +8 位作者 Jinke Wang Rongqiao Wang Xiuchun Liu Kai Gao Jingli Sun Yong Yuan Lingwei Ma Hongchang Qian Dawei Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期119-126,共8页
The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties ... The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal materials.However,limited studies have applied ACM to the corrosion protection properties of organic coatings.This study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over time.Coatings with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in real-time.Throughout the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy coating.The trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface analysis.This alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic coatings.Compared with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating. 展开更多
关键词 atmospheric corrosion monitoring technology corrosion inhibitor COATING carbon steel corrosion protection
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Role of land-atmosphere coupling in persistent extreme climate events in eastern China in summer 2022
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作者 Yue Chen Aihui Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期19-26,共8页
2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足... 2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足,蒸散主要受限于陆面有效能量.然而,潜在机制研究指出,2022年土壤湿度对蒸散的限制作用在上述区域异常偏强,土壤湿度与气候要素之间的强反馈可能在2022年复合极端事件的演变和持续中发挥了关键作用。 展开更多
关键词 复合极端事件 陆气耦合 土壤湿度 干旱 中国东部
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新疆地区GGOS Atmosphere加权平均温度的精化 被引量:13
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作者 谢劭峰 黎峻宇 +1 位作者 刘立龙 黄良珂 《大地测量与地球动力学》 CSCD 北大核心 2017年第5期472-477,共6页
绝大多数地基GPS站观测时未进行测站上空气象观测,导致无法获得精确的大气加权平均温度(GT_m),限制了地基GPS遥感水汽的应用。基于此,本文分析了利用GGOS Atmosphere T_m格网数据获取新疆地区加权平均温度(T_m)的方法。利用无线电探空... 绝大多数地基GPS站观测时未进行测站上空气象观测,导致无法获得精确的大气加权平均温度(GT_m),限制了地基GPS遥感水汽的应用。基于此,本文分析了利用GGOS Atmosphere T_m格网数据获取新疆地区加权平均温度(T_m)的方法。利用无线电探空资料评估由GGOS Atmosphere加权平均温度格网数据计算得到的GT_m的精度,通过考虑季节和地理变化的精化模型对GT_m进行改正。结果表明,利用平均值插值方法得到的GT_m经过精化模型改正后,可以满足新疆地区地基GPS精密遥感水汽的要求。 展开更多
关键词 GGOS atmosphere 加权平均温度 新疆地区 GTm精化模型 平均值插值
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EFFECTS OF BRAZING ATMOSPHERES ON INTERFACIAL MICROSTRUCTURE BETWEEN DIAMOND GRITS AND BRAZING ALLOY 被引量:3
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作者 陈燕 徐鸿钧 +1 位作者 傅玉灿 苏宏华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期248-253,共6页
The samples of brazed diamond grits with NiCr brazing alloy are prepared in vacuum and argon gas. The microstructures are analyzed with scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS... The samples of brazed diamond grits with NiCr brazing alloy are prepared in vacuum and argon gas. The microstructures are analyzed with scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction(XRD). The effects of brazing atmospheres on the as-brazed NiCr brazing alloy composite structures and interracial microstructure are studied between diamond grits and brazing alloy. Results show that: (1) There are different composite structures of as-brazed NiCr brazing alloy under different oxygen partial pressures in vacuum and argon gas. B203 exists on the surface of the brazed samples under argon gas furnace brazing. It indicates that oxygen plays an important role in the resultants of as-brazed NiCr brazing alloy during the brazing process. (2) There are different interfacial microstructures in different brazing atmospheres, but the main reaction product is chromium carbides. The chromium carbides in argon gas furnace brazing grow in a disordered form, but those in vacuum furnace brazing grow radiated. And the scale of grains in argon gas is smaller than those in vacuum. 展开更多
关键词 DIAMOND composite structures INTERFACES MICROSTRUCTURE brazing atmospheres
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Effect of sintering atmosphere on corrosion resistance of Ni/(NiFe_2O_4-10NiO) cermet inert anode for aluminum electrolysis 被引量:3
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作者 田忠良 郭伟昌 +2 位作者 赖延清 张凯 李劼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2925-2929,共5页
A comparative study on the corrosion resistance of 17Ni/(NiFe2O4-10NiO) cermet inert anode prepared in differentsintering atmospheres was conducted in Na3AlF6-Al2O3 melt. The results indicate that the corrosion rate... A comparative study on the corrosion resistance of 17Ni/(NiFe2O4-10NiO) cermet inert anode prepared in differentsintering atmospheres was conducted in Na3AlF6-Al2O3 melt. The results indicate that the corrosion rates of NiFe2O4-based cermetanodes prepared in the vacuum and the atmosphere with oxygen content of 2×10^-3 (volume fraction) are 6.46 and 2.71 cm/a,respectively. Though there is a transition layer with lots of holes or pores, a densified layer is formed on the surface of anode due tosome reactions producing aluminates. For the anode prepared in the atmosphere with oxygen content of 2×10^-3, the thickness of thedensification layer (about 50 μm) is thicker than that (about 30 μm) formed on the surface of anode prepared in the vacuum. Thecontents of NiO and Fe(II) in NiFe2xO4-y-z increase with the decrease of oxygen content in sintering atmosphere, which reduces thecorrosion resistance of the material. 展开更多
关键词 sintering atmosphere corrosion resistance NiFe2O4-based cermet inert anode aluminum electrolysis
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Prediction of SO_2 Concentration in Urban Atmosphere Based on B-P Neural Network 被引量:1
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作者 姚建 王丽梅 袁野 《Meteorological and Environmental Research》 CAS 2010年第11期9-11,14,共4页
Base on the principle and method of B-P neural network,the prediction model of SO2 concentration in urban atmosphere was established by using the statistical data of a city in southwest China from 1991 to 2009,so as t... Base on the principle and method of B-P neural network,the prediction model of SO2 concentration in urban atmosphere was established by using the statistical data of a city in southwest China from 1991 to 2009,so as to forecast atmospheric SO2 concentration in a city of southwest China.The results showed that B-P neural network applied in the prediction of SO2 concentration in urban atmosphere was reasonable and efficient with high accuracy and wide adaptability,so it was worthy to be popularized. 展开更多
关键词 B-P neural network SO2 concentration in urban atmospheric Prediction model China
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Effect of Carbon Dioxide (CO_2) Controlled Atmosphere on Superoxide Dismutase (SOD) Activity of Three Storage Pests in Chinese Medicinal Materials 被引量:2
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作者 李灿 《Plant Diseases and Pests》 CAS 2011年第4期43-45,共3页
[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action... [ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action of controlled atmosphere stress on insect. [ Method] Using nitrotetrazolium blue chloride (NBT) light reduction method, SOD activity of drugstore beetle ( Stegobium panlceum ), cigarette beetle ( Lasioderma serricorne) and coffee bean beetle (Araecerus fasciculatus) was studied, and the stress response of the enzyme under controlled atmosphere stress of CO2 was analyzed. [ Result ] SOD activity of drugstore beetle, cigarette beetle and coffee bean beetle exposed to controlled atmosphere stress of high concentrations of CO2 for 3 and 6 h had certain degree of increase, and the activity sig- nificantly increased from 2.011±0.954,2.664±0.218 and 1.458±0.718 to 3. 135±0. 105,3.050±0.673 and 2.975±0.229 U/(per pest · 30 min) after treat- ment for 6 h. [ Conclusion] Controlled atmosphere stress of high concentrations of CO2 had certain activation effect on SOD activity of storage pest in Chinese me- dicinal material within the context of sub-lethal events. The results could enrich the insecticidal mechanism of controlled atmosphere and theoretical system of analy- sis on insect resistance to controlled atmosphere. 展开更多
关键词 Chinese medicinal materials Storage pest Superoxide dismulase Enzyme activity CO2 controlled atmosphere China
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基于GGOS Atmosphere数据的ZHD模型精度分析 被引量:1
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作者 丁茂华 胡伍生 《测绘与空间地理信息》 2017年第3期11-13,21,共4页
对流层天顶干延迟(ZHD)建模是对流层延迟建模的一个重要组成部分,由于ZHD变化较为规律,因此,通常用模型来表达。而对流层天顶湿延迟(ZWD)变化不规则且随机性大,所以在GNSS处理中将它作为一个未知的待估参数。不精确的ZHD模型,会影响到ZW... 对流层天顶干延迟(ZHD)建模是对流层延迟建模的一个重要组成部分,由于ZHD变化较为规律,因此,通常用模型来表达。而对流层天顶湿延迟(ZWD)变化不规则且随机性大,所以在GNSS处理中将它作为一个未知的待估参数。不精确的ZHD模型,会影响到ZWD估算的准确性,因此,选择精确合理的ZHD模型具有重要的意义。传统无线电探空仪数据获取的ZHD由于不能覆盖全球所有位置,尤其是海洋地区,而且在特殊天气使用也受限。为了更能全面反映ZHD模型的精度,本文尝试使用GGOS Atmosphere数据比较分析3种经典ZHD模型、即Saastamoinen模型、Hopfield模型和Black模型。通过对全球范围内的657个站点且时间覆盖长达5年的GGOS Atmosphere数据进行比较分析,我们得到以下结论:Saastamoinen模型优于Hopfield模型和Black模型,Saastamoinen模型的ZHD的精度可以优于1.5 mm。因此,在GNSS用户使用ZHD模型时,Saastamoinen模型可以作为使用模型。具体可以应用到GNSS大地测量学、GNSS车辆导航定位以及GNSS气象学。 展开更多
关键词 GGOS atmosphere Saastamoinen模型 HOPFIELD模型 Black模型
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Conversion of Pretreated Biomass into Levulinic Acid via Continuous Extraction at Atmosphere Pressure
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作者 范明慧 闫立峰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期92-98,I0004,共8页
Conversion of biomass to chemicals or fuels under mild condition is still a challenge. As a platform molecule for chemicals and fuels, levulinic acid (LA) has been prepared by lique-faction of biomass at high pressu... Conversion of biomass to chemicals or fuels under mild condition is still a challenge. As a platform molecule for chemicals and fuels, levulinic acid (LA) has been prepared by lique-faction of biomass at high pressure. In order to carry out the conversion from wheat straw to LA at atmosphere pressure, continuous extraction of the reactive system by an organic solvent with a higher density than that of water was utilized for degradation of pretreated biomass. Yields of LA were measured by means of gas chromatography-mass spectrometry and nuclear magnetic resonance. The results revealed that a maximum yield of 30.66% of LA can be obtained from wheat straw. In addition, the effects of biomass pretreated conditions on the LA conversion have been studied. The study provides a new route to convert biomass to valuable chemicals at atmosphere pressure. 展开更多
关键词 BIOMASS Pretreatment Continuous extraction Levulinic &cid atmosphere pressure
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水力负荷对Atmosphere-Exposed Biofilm(AEB)净化效果的影响 被引量:2
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作者 王必胜 金明姬 +1 位作者 徐明哲 齐书亭 《西南农业学报》 CSCD 北大核心 2016年第12期2971-2974,共4页
本文采用Atmosphere-Exposed Biofilm(AEB)处理模拟废水,调查分析了水力负荷(4.3、8.5、12.7、17.0、21.3rn/d)对系统处理特性的影响。结果表明,水力负荷对COD、TN、TP具有不同程度的影响,COD、TN、TP最佳去除率分别出现17... 本文采用Atmosphere-Exposed Biofilm(AEB)处理模拟废水,调查分析了水力负荷(4.3、8.5、12.7、17.0、21.3rn/d)对系统处理特性的影响。结果表明,水力负荷对COD、TN、TP具有不同程度的影响,COD、TN、TP最佳去除率分别出现17.0、17.0、21.3m/d。在17.0~21.3m/d负荷范围内,COD、TN出水浓度满足了《城镇污水处理厂污染物排放标准》一级A标准,TP满足一级B标准。在所有运行范围内,系统COD、TN、TP去除速率相对恒定。系统水力负荷与进出水浓度比(C/C0)拟合结果,水力负荷与系统处理特性具有一定相关性。综合水力负荷对系统处理特性的影响,水力负荷为17.0m/d时,Atmosphere.Exposed Biofilm(AEB)系统处理效果较优。 展开更多
关键词 atmosphere—Exposed BIOFILM 水力负荷 处理特性 去除速率
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Copper corrosion in hot and dry atmosphere environment in Turpan, China 被引量:3
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作者 孔德成 董超芳 +4 位作者 方月华 肖葵 郭春云 何刚 李晓刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第6期1721-1728,共8页
The atmospheric corrosion behavior of pure copper exposed for three years in Turpan, China, which is a typical hot and dry atmosphere environment, was investigated using mass-loss tests, morphology observations, com... The atmospheric corrosion behavior of pure copper exposed for three years in Turpan, China, which is a typical hot and dry atmosphere environment, was investigated using mass-loss tests, morphology observations, composition analyses, and electrochemical techniques. The results indicated that the annual corrosion rate of pure copper was approximately 2.90 μm/a. An uneven distribution of corrosion products was observed by scanning electron microscopy; this uneven distribution was attributed to the dehydration process during wet–dry and cold–hot cycles, and the compositions mainly consisted of cuprite (Cu2O) and atacamite (Cu2Cl(OH)3). Electrochemical measurements showed that deposits on copper improved its resistance to corrosion and the protectiveness decreased with increasing temperature. On the other hand, results obtained using the scanning vibrating electrode technique showed that the porous and uneven structure of the deposit layer generated a spatial separation of cathodic and anodic reaction sites, which accelerated the corrosion process in wet and rainy weather. 展开更多
关键词 COPPER atmospheric corrosion composition analysis electrochemical technology
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On Delightful Class Atmosphere in Higher Vocational College English Learning
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作者 唐志娟 《海外英语》 2017年第21期228-229,共2页
Higher vocational college students are suffering more foreign language anxiety in their English learning.Based on this status quo,the writer poses some pedagogical implication from the perspectives of how to create de... Higher vocational college students are suffering more foreign language anxiety in their English learning.Based on this status quo,the writer poses some pedagogical implication from the perspectives of how to create delightful class atmosphere and reduce students' foreign language anxiety.It is hoped that the findings will help students more effectively learn foreign language. 展开更多
关键词 foreign language anxiety delightful class atmosphere English learning
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温度对改良后Atmosphere-exposed Biofilm系统处理特性的影响
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作者 王颖 聂冬 金明姬 《科学技术与工程》 北大核心 2018年第17期332-336,共5页
研究利用改良后Atmosphere-exposed Biofilm系统处理了模拟废水,调查分析了温度对改良后系统处理性能的影响。同时,通过菲尔普斯公式探求了改良后系统的温度系数。结果,在10~35℃温度范围内,改良后Atmosphere-exposed Biofilm系统的COD... 研究利用改良后Atmosphere-exposed Biofilm系统处理了模拟废水,调查分析了温度对改良后系统处理性能的影响。同时,通过菲尔普斯公式探求了改良后系统的温度系数。结果,在10~35℃温度范围内,改良后Atmosphere-exposed Biofilm系统的COD、TN及TP出水浓度呈下降趋势,去除率及去除速率呈上升趋势,与改良前相比系统在低温及高温阶段TN、TP的处理具有一定耐温性。改良后系统的COD、TN及TP温度系数分别为1.007 3、1.029 7及1.030 6,温度对TP的影响最大。 展开更多
关键词 atmosphere-exposed BIOFILM 改良 温度 处理特性 温度系数
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Effects of Active Modified Atmosphere Packaging on Postharvest Quality of Shiitake Mushrooms (Lentinula edodes) Stored at Cold Storage 被引量:41
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作者 YE Jing-jun LI Jian-rong +3 位作者 HAN Xiao-xiang ZHANG Lei JIANG Tian-jia XIA Miao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第3期474-482,共9页
The effects of active modified atmosphere packaging (MAP) on the postharvest quality of shiitake mushrooms stored at cold temperature (4°C) were investigated.The gas components were 2% O2 +7% CO2 (MAP1),2%... The effects of active modified atmosphere packaging (MAP) on the postharvest quality of shiitake mushrooms stored at cold temperature (4°C) were investigated.The gas components were 2% O2 +7% CO2 (MAP1),2% O2 +10% CO2 (MAP2) and 2% O2 +13% CO2 (MAP3),respectively.The results showed that active MAP could extend the shelf-life of shiitake mushrooms to 17 d and the concentration of carbon dioxide could influence the postharvest quality of shiitake mushrooms.MAP2 treatment inhibited the increase in respiration rate and malondinaldehyde (MDA) contents,delayed the decrease in firmness,soluble sugar and vitamin C,and obviously reduced the activity of polyphenol oxidase (PPO) and the degree of browning,therefore maintaining better quality. 展开更多
关键词 shiitake mushrooms modified atmosphere package (MAP) postharvest quality
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