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Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine heikkinen Eva Partoll Yvette Gramlich Wei huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik Gmbh Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

Fe-Si particles on the surface of blast furnace coke

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 697-703页

作者： Stanislav S.Gornostayev Eetu-Pekka heikkinen Jyrki J.heino Timo M.J.Fabritius Process Metallurgy Group University of Oulu

This study investigates the surface of unpolished samples of blast furnace （BF） coke drilled from the tuyere zone, which hosts Fe-Si particles （mostly Fe3Si） that vary in size, shape, depth of submersion （penetration） into the coke matrix, and contact features with the surface. Based on the shape of the particles and the extent of their contact with the coke matrix, they have been grouped into three major types：（I） sphere-like droplets with limited contact area, （II） semi-spheres with a larger contact area, and （III） irregular segregations with a spherical surface, which exhibit the largest contact area among the three types of particles. Considering the ratio between the height （h） of the particles and half of their length at the surface level （/） along the cross-section, these three types can be characterized as follows：（I） h 〉/, （II） h ~/, and （1II） h 〈/. All the three types of particles can be found near each other. The shape and the extent of the contact depend on the de- gree of penetration of the material into the matrix, which is a function of the composition of the particles. Type （I） particles were initially saturated with Si at an earlier stage and, for that reason, they can react less with carbon in the coke matrix than type （II） and （III）, thereby moving faster through the coke cone. Thermodynamic calculations have shown that the temperature interval of 1250-1300~C can be consid- ered the starting point for Si entering into molten iron under quartz-dominated coke ash. Accordingly, the initial pick-up of Si by molten iron can be assumed to be mineral-related. In terms of BF practice, better conditions for sliding Fe-Si droplets through the coke cone are available when they come into contact with free SiO2 concentrated into small grains, and when the SiO2/∑MexOy mass ratio in the coke ash is high.

关键词： blast furnace practice metallurgical coke molten iron iron silicide

初级卫生保健采用超声检查评估消化不良的临床价值

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世界核心医学期刊文摘（胃肠病学分册） 2006年第1期2卷 60-61页

作者： heikkinen M. Rsnen h. Frkkil M. 成虹 Department of Medicine Unit of Gastroenterology Kuopio University Hospital FIN-70210 Kuopio FinlandDr.

Objective. In general practice, upper abdominal ultrasound (US) is widely used in the evaluation of patients with dyspepsia. however, there is a dearth of published data on the role of US in the dyspepsia work-up. There are no data on the use of US as a follow-up study in functional dyspepsia. The aims of this study were to assess the role of US in evaluating dyspepsia, and to assess the long-term clinical relevance of minor findings revealed by US in patients with functional dyspepsia. Material and methods. Four hundred consecutive dyspeptic patients were recruited. At baseline, all patients underwent gastroscopy and US. Patients were divided into two groups: “ endoscopy-negative patients" and “ endoscopy-positive patients". “ The endoscopy-negative" group included all cases in which the final diagnoses could not be settled after gastroscopy. US was repeated after 6-7 years in patients who had functional dyspepsia. Results. In the endoscopy-negative group, gallstones were detected in 21 patients, but this was considered to be a cause of symptoms in 9 patients. No malignant lesions were detected by US in the endoscopy-negative group. In the endoscopypositive group, a malignant tumor in the kidney was suspected in 3 patients. Only one of these tumors turned out to be an incidental small carcinoma. Moreover, several minor findings were shown by US: usually these consisted of abnormal echogenicity of the liver. During the follow-up period, 6 patients developed gallstones. At the end of the follow-up period, two clinically significant findings were diagnosed: a small renal cancer and hydronephrosis. Conclusions. This study shows that the wide, untargeted use of abdominal US in the evaluation of patients with dyspepsia following a gastroscopy is not necessary. Repeated US examination in cases of functional dyspepsia is not recommended, and rarely changes the diagnosis.

关键词：超声检查卫生保健肝脏回声肾盂积水内镜阴性胆囊结石临床相关性微小病变胃镜检查小肾癌

颅脑损伤周围区域脑血流变化与感觉运动障碍有关(英文)

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中华神经外科疾病研究杂志 2010年第2期9卷 141-141页

作者： Immonen R heikkinen T Thtivaara L Nurmi A Stenius TK Puolivli J Tuinstra T Phinney AL Van Vliet B Yrjnheikki J Grhn O

In the traumatic brain injury(TBI) the initial impact causes both primary injury,and launches secondary injury *** consequence,and a factor that may contribute to these secondary changes and functional outcome,is altered *** relative cerebral blood volume(CBV) changes in rat brain after severe controlled cortical impact injury were characterized to assess their interrelations with motor function *** resonance imaging(MRI) was performed 1,2,4 h,and 1,2,3,4,7,and 14 days after TBI to quantify CBV and water *** test was conducted before,and 2,7,and 14 days after the *** found distinct temporal profile of CBV in the perilesional area,hippocampus,and in the primary *** all regions,the first response was drop of *** CBV was reduced for over 4 days thereafter gradually *** the initial drop,the hippocampal CBV was increased for 2 *** demonstrated severely impaired motor functions 2 days after injury(33% decrease),which then slowly recovered in 2 *** recovery parallelled the recovery of perifocal *** MRI can detect cerebrovascular pathophysiology after TBI in the vulnerable perilesional area,which seems to potentially associate with time course of sensory-motor deficit.

关键词：神经外科疾病临床医学摘要