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Explaining the influence of dopant concentration and excitation power density on the luminescence and brightness of β-NaYF4:Yb^3+,Er^3+ nanoparticles:Measurements and simulations

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Nano Research 2019年第8期12卷 1871-1879页

作者： Martin Kaiser christian Wurth Marco Kraft Tero Soukka Ute Resch-genger Division Biophotonics Federal Institute for Materials Research and Testing (BAM)Richard-Willstaetter-Str. 11D-12489 BerlinGermany Department of Biotechnology University of TurkuKiinamyllynkatu 10TurkuFI-20520Finland

We assessed the influence of Yb^3+ and Er34 dopant concentration on the relative spectral distribution, quantum yield (Фuc), and decay kinetics of the upconversion luminescence (UCL) and particle brightness (BUC) for similarly sized (33 nm) oleate-capped p-NaYF4:Yb3t,Er^3+ upconversion (UC) nanoparticles (UCNPs) in toluene at broadly varied excitation power densities (F). This included an Yb^3+ series where the Yb^3+ concentration was varied between 11%—21% for a constant Er^3+ concentration of 3%, and an Er^3+ series, where the Er^3+ concentration was varied between 1%-4% for a constant Yb^3+ concentration of 14%. The results were fitted with a coupled rate equation model utilizing the UCL data and decay kinetics of the green and red Er34 emission and the Yb34 luminescence at 980 nm. An increasing Yb34 concentration favors a pronounced triphotonic population of 4F9/2 at high P by an enhanced back energy transfer (BET) from the 4g11/2 level. Simultaneously, the Yb^3+-controlled UCNPs absorption cross section overcompensates for the reduction in Фuc with increasing Yb^3+ concentration at high P, resulting in an increase in Sue. Additionally, our results show that an increase in Yb34 and a decrease in Er^3+ concentration enhance the color tuning range by P. These findings will pave the road to a deeper understanding of the energy transfer processes and their contribution to efficient UCL, as well as still debated trends in green-to-red intensity ratios of UCNPs at different P.

关键词： upconversion quantum yield color tuning nanoparticles dopant concentration rate equation model

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Characterization of focal liver lesions with SonoVue~-enhanced sonography: International multicenter-study in comparison to CT and MRI

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World Journal of gastroenterology 2009年第30期15卷 3748-3756页

作者： Hervé Trillaud Jean-Michel Bruel Pierre-Jean Valette Valérie Vilgrain gérard Schmutz Raymond Oyen Wieslaw Jakubowski Jan Danes Vlastimil Valek christian greis Department of radiology University of Victor Segalen Bordeaux 2CHU Bordeaux Hospital Saint André1 rue Jean Burguet33075 BordeauxFrance Department of radiology CHU of Montpellier HospitalSaint Eloi34295 MontpellierCedex 5France Department of radiology CHU Lyon University69437 Lyon Cedex 03France Department of radiology Hospital Beaujon92110 ClichyFrance Department of radiology Hospital CaenCaen14033 Caen CedexFrance Department of radiology University Hospitals LeuvenGasthuisbergHerestrat 493000 LeuvenBelgium Department of radiology Zaklad Diagnostyki ObrazowejWojewodzki Zespol Publicznych ZakladowOpieki Zdrowotnejul Kendrtatowicza 803-242 WarszawaPoland Department of Radiology General University HospitalU Nemocnice 212000 Praha 2Czech Republic Department of Radiology University Hospital Brno BohuniceJihlavka 2063900 BrnoCzech Republic Ultrasound Medical Department Bracco Imaging Deutschland GmbHMax-Stromeyer-Strasse 11678467 KonstanzGermany

AIM： To evaluate in a multicenter study whether the sonographic characterization of focal liver lesions can be improved using SonoVue-enhancement; and to compare this method with computed tomography （CT） and magnetic resonance imaging （MRI）. METHODS： One hundred and thirty four patients withone focal liver lesion detected in baseline ultrasound （US） were examined with conventional US, contrastenhanced US （n = 134）, contrast-enhanced CT （n = 115） and/or dynamic contrast-enhanced MRI （n = 70）. The lesions were classified as malignant, benign or indeterminate and the type of lesion was determined. The final diagnosis based on the combined information of all imaging examinations, clinical information and histology （n = 32） was used. Comparisons were made to see whether the addition of contrast-enhanced US led to the improvement of the characterization of doubtful focal liver lesions.RESULTS： In comparison with unenhanced US, SonoVue markedly improves sensitivity and specificity for the characterization （malignant/benign） of focal liver lesions. In comparison with CT and/or dynamic MRI, SonoVue -enhanced sonography applied for characterization of focal liver lesions was 30.2% more sensitive in the recognition of malignancy and 16.1% more specific in the exclusion of malignancy and overall 22.9% more accurate. In the subgroup with confirmative histology available （n = 30）, sensitivity was 95.5% （CEUS）, 72.2% （CT） and 81.8% （MRI）, and specificity was 75.0% （CEUS）, 37.5% （CT） and 42.9% （MRI）. The sensitivity and specificity of CEUS for the identification of focal nodular hyperplasia （FNH） and hemangiomas was 100% and 87%, resulting in an accuracy of 94.5%.CONCLUSION： SonoVue-enhanced sonography emerges as the most sensitive, ost specific and thus most accurate imaging modality for the characterization of focal liver lesions.

关键词： Contrast-enhanced sonography Contrastmedia Dynamic sonography Liver lesion Liverdisease Liver Oncologic imaging Sonography

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Single and multiple stressor effect of road deicers and Cu on Atlantic salmon (Salmo salar) alevins from hatching till swim-up

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Journal of Environmental Sciences 2018年第4期30卷 368-378页

作者： Urma Mahrosh BjФrn Olav Rosseland Brit Salbu Hans-christian Teien Nortuegian Uniuersity of Life Sciences Department of Environmental Sciences N-1432 As Norway National University of Sciences and Technology H-12 Islamabad Pakistan Norwegian University of Life Sciences Department of Ecology and Natural Resource Management N-1432 As Norway

Road salts are frequently used for deicing of roads in the Nordic countries. During snow-melt, the road run-off containing high concentrations of road salt and various metals such as Cu remobilized from sand, silt and dust may negatively influence organisms in downstream receiving water bodies. The present work focuses on the impact of road salt（NaCl） and Cu, separately and in mixtures on Atlantic salmon alevins from hatching till swim-up. The results showed that high road salt concentrations could induce a series of negative effects in alevins such as reduced growth, deformities, delayed swim-up and mortality. For alevins exposed to all tested road salt concentrations（100–1000 mg/L）,mortality was significantly higher compared to control. In exposure to Cu solutions（5–20 μg Cu/L）, no effects on growth, morphology, swim-up or mortality of alevins compared to control were observed. In mixture solutions（road salt and Cu）, ultrafiltration of the exposure water demonstrated that only 20%–40% of Cu was present as positively charged low molecular mass（LMM） Cu species assumed to be bioavailable. When exposed to road salt and Cu mixtures, negative effects in alevins such as reduced growth, deformities,delayed swim-up and mortality were observed. The overall results indicated that the road salt application could seriously affect sensitive life stages of Atlantic salmon, and application of road salt should be avoided during the late winter–early spring period.

关键词： Road deicers Copper Atlantic salmon Alevins Biological effects

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Preventing the Immense Increase in the Life-Cycle Energy and Carbon Footprints of LLM-Powered Intelligent Chatbots

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Engineering 2024年第9期40卷 202-210页

作者： Peng Jiang christian Sonne Wangliang Li Fengqi You Siming You Department of Industrial Engineering and Management Business SchoolSichuan UniversityChengdu 610064China Department of Ecoscience Aarhus UniversityRoskilde DK-4000Denmark Chinese Academy of Sciences Key Laboratory of green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Systems Engineering Cornell UniversityIthacaNY 14853USA James Watt School of Engineering University of GlasgowGlasgow G128QQUK

Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial *** frontier technology companies are feverishly participating in LLM-powered chatbot design and development,providing several alternatives beyond the famous ***,training,fine-tuning,and updating such intelligent chatbots consume substantial amounts of electricity,resulting in significant carbon *** research and development of all intelligent LLMs and software,hardware manufacturing(e.g.,graphics processing units and supercomputers),related data/operations management,and material recycling supporting chatbot services are associated with carbon emissions to varying *** should therefore be paid to the entire life-cycle energy and carbon footprints of LLM-powered intelligent chatbots in both the present and future in order to mitigate their climate change *** this work,we clarify and highlight the energy consumption and carbon emission implications of eight main phases throughout the life cycle of the development of such intelligent *** on a life-cycle and interaction analysis of these phases,we propose a system-level solution with three strategic pathways to optimize the management of this industry and mitigate the related *** anticipating the enormous potential of this advanced technology and its products,we make an appeal for a rethinking of the mitigation pathways and strategies of the life-cycle energy usage and carbon emissions of the LLM-powered intelligent chatbot industry and a reshaping of their energy and environmental implications at this early stage of development.

关键词： Large language models Intelligent chatbots Carbon emissions Energy and environmental footprints Life-cycle assessment global cooperation

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Phase evolution and properties of glass ceramic foams prepared by bottom ash,fly ash and pickling sludge

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International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 563-573页

作者： Junjie Zhang Xiaoyan Zhang Bo Liu christian Ekberg Shizhen Zhao Shengen Zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde graduate School University of Science and Technology BeijingFoshan 528399China Nuclear Chemistry and Industrial Material Recycling Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGothenburg 41296Sweden

Municipal solid waste incineration products of bottom ash(BA),fly ash(FA),and pickling sludge(PS),causing severe environ-mental pollution,were transformed into glass ceramic foams with the aid of CaCO3 as a pore-foaming agent during *** effect of the BA/FA mass ratio on the phase composition,pore morphology,pore size distribution,physical properties,and glass structure was investigated,with results showing that with the increase in the BA/FA ratio,the content of the glass phase,Si-O-Si,and Q3Si units decrease *** glass transmission temperature of the mixture was also *** combined,the glass viscosity decreases,causing bubble coalescence and uneven pore *** ceramic foams with uniform spherical pores are *** the content of BA,FA,and PS are 35wt%,45wt%,and 20wt%,respectively,contributing to high performance glass ceramic foams with a bulk density of 1.76 g/cm3,porosity of 56.01%,and compressive strength exceeding 16.23 *** versatile and low-cost approach provides new insight into synergistically recycling solid wastes.

关键词： glass ceramic foams bottom ash fly ash picking sludge pore structure glass units

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Steam Pretreatment of Rice Hulls to Release Fermentable Saccharides:An Approach to Improve Recovery of(Hemi)Cellulosic Sugars Through Multivariate Design

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Rice science 2021年第5期28卷 501-510,I0037-I0039页

作者： Sheila MONTIPO christian Roslander Marli Camassola Mats galbe Ola Wallberg Department of Chemical Engineering Lund UniversityP.O.Box 124Lund SE-22100Sweden Biotechnology Institute University of Caxias do SulCaxias do Sul 95070-560Brazil

The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the *** carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.

关键词： ligno cellulosic feedstock sulfur dioxide high solid loading hydrolysis central composite rotatable design

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Measurement of heterogeneous uptake of NO2 on inorganic particles, sea water and urban grime

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Journal of Environmental Sciences 2021年第8期33卷 124-135页

作者： Chuan Yu Zhe Wang Qingxin Ma Likun Xue christian george Tao Wang Environment Research Institute Shandong UniversityQingdao 266237China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Univ Lyon UniversitéClaude Bernard Lyon 1Centre National de la Recherche Scientifique(CNRS)Institut de Recherches sur la Catalyse et l’Environnement de Lyon(IRCELYON)Villeurbanne F-69626France

Heterogeneous reactions of NO2 on different surfaces play an important role in atmospheric NOxremoval and HONO formation,having profound impacts on photochemistry in polluted urban *** studies have suggested that the NO2 uptake on the ground or aerosol surfaces could be a dominant source for elevated HONO during the ***,the uptake behavior of NO2 varies with different surfaces,and different uptake coefficients were used or derived in different *** obtain a more holistic picture of heterogeneous NO2 uptake on different surfaces,a series of laboratory experiments using different flow tube reactors was conducted,and the NO2 uptake coefficients(γ)were determined on inorganic particles,sea water and urban *** results showed that heterogeneous reactions on those surfaces were generally weak in dark conditions,with the measuredγvaried fromgrime was observed,with the obvious formation of HONO and NO from the heterogeneous *** photo-enhancedγwas measured to be 1.9×10-6 at 5%relative humidity(RH)and 5.8×10-6 at 70%RH on urban grime,showing a positive RH dependence for both NO2 uptake and HONO *** results demonstrate an important role of urban grime in the daytime NO2-to-HONO conversion,and could be helpful to explain the unknown daytime HONO source in the polluted urban area.

关键词： NO2 uptake HONO source Heterogeneous uptake coefficient Urban grime

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N-Propionylmannosamine stimulates axonal elongation in a murine model of sciatic nerve injury

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Neural Regeneration Research 2015年第6期10卷 976-981页

作者： christian Witzel Werner Reutter g.Bj?rn Stark georgios Koulaxouzidis Plastic and Reconstructive Surgery Interdisciplinary Breast CenterCharité–Universit?tsmedizin Berlin Institute of Laboratory Medicine Clinical Chemistry and PathobiochemistryCharité–Universit?tsmedizin Berlin Department of Plastic and Hand Surgery University of Freiburg Medical Centre

Increasing evidence indicates that sialic acid plays an important role during nerve regeneration. Sialic acids can be modified in vitro as well as in vivo using metabolic oligosaccharide engineering of the N-awl side chain. N-Propionylmannosamine （ManNProp） increases neurite outgrowth and accelerates the reestablishment of functional synapses in vitro. We investigated the influence of systemic ManNProp application using a specific in vivo mouse model. Using mice expressing axonal fluorescent proteins, we quantified the extension of regenerating axons, the number of regenerating axons, the number of arborising axons and the number of branches per axon 5 days after injury. Sciatic nerves from non-expressing mice were grafted into those expressing yellow fluorescent protein. We began a twice-daily intraperitoneal application of either peracetylated ManNProp （200 mg/kg） or saline solution 5 days before injury, and continued it until nerve harvest （5 days after transection）. ManNProp significantly increased the mean distance of axonal regeneration （2.49 mm vs. 1.53 mm; P 〈 0.005） and the number of arborizing axons （21% vs. 16%; P = 0.008） 5 days after sciatic nerve grafting. ManNProp did not affect the number of regenerating axons or the number of branches per arborizing axon. The biochemical glycoengineering of the N-acyl side chain of sialic acid might be a promising approach for improving peripheral nerve regeneration.

关键词： N-propionylmannosamine sialic acid glycoengineering sciatic nerve peripheral nerve branching arborisation Thyl-YFP mouse nerve regeneration

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PLA2g7: a new player in shaping energy metabolism and lifespan

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2128-2129页

作者： Lena Susanna Candels Svea Becker christian Trautwein Department of Medicine III University Hospital RWTH AachenAachenGermany

In a recent study published in science,Spadaro and colleagues described the downregulation of PLA2g7 through sustained calory restriction as a crucial factor for lowering inflammatory mechanisms and contributing to ***2g7’s identification as a critical regulatory gene is important to better understand the role of adipose tissue metabolism in regulating immune-metabolic *** data show that long-term calorie restriction(CR)improves health and extends life expectancy.1 Chronic 40%CR increases susceptibility to infections in mice,shortening their *** contrast,the Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy(CALERIE)analysis found that moderate CR in humans over 24 months did not reduce immune functions.14%sustained CR was associated with improved adipose tissue metabolism,decreased inflammation,and reduced thymic *** et *** that low platelet activating factor acetyl hydrolase(PLA2g7)correlates with immune-metabolic consequences of CR and contributes to decreased inflammation and a longer lifespan in healthy mid-aged adults.1 PLA2g7 is a lipoprotein-associated calcium-independent phospholipase A2 involved in phospholipid catabolism during inflammatory and oxidative stress responses.

关键词： metabolism sustained PLA2

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Effects of Aluminum Particle Size, galinstan Content and Reaction Temperature on Hydrogen generation Rate Using Activated Aluminum and Water

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Energy and Power Engineering 2015年第9期7卷 426-432页

作者： Kandasamy Jayaraman christian Chauveau Iskender gö kalp CNRS-ICARE 1C Av. de la Recherche Scientifique Orléans France

Aluminum, in its normal passive oxidized state, does not react with water. In this work, aluminum activation is carried out using liquid metal eutectics ga-In-Sn-Zn (60:25:10:5). Subsequently, the reaction with water of activated aluminum to produce hydrogen has been examined. The effects of aluminum particle size, liquid eutectics content, and reaction temperature on hydrogen production rates are investigated. The liquid eutectics interaction with aluminum is discussed and the mechanisms of liquid eutectics penetration within the Al particles have been investigated. The specific surface area of the Al particles, the mass ratio of Al to eutectics content and the reaction temperature were found to determine the hydrogen production rate and yield. It is observed that micro-aluminum particles of ~30 μm size display lower reaction rates and hydrogen yields than ~350 μm size particles.

关键词： Hydrogen generation Aluminum Particles Liquid Metal Eutectics

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