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矿物岩石地球化学通报 2017年第5期36卷 806-806页

作者： Yannick Buret Jrn-Frederik Wotzlaw Stan Roozen Marcel Guillong Albrecht von Quadt christoph a.heinrich 袁超

建立深成岩与火山岩研究之间的有机联系,对于理解从火山喷发到岩浆-热液矿床形成的各种岩浆过程是非常必要的。斑岩铜矿床普遍与规模较大且长期活动的火山中心有密切联系,但是关于矿化侵入体与火山喷发的时间和动力学机制方面的联系仍... 详细信息

建立深成岩与火山岩研究之间的有机联系,对于理解从火山喷发到岩浆-热液矿床形成的各种岩浆过程是非常必要的。斑岩铜矿床普遍与规模较大且长期活动的火山中心有密切联系,但是关于矿化侵入体与火山喷发的时间和动力学机制方面的联系仍存在很大的争议。

关键词：斑岩铜矿床火山岩深成岩年代学证据锆石系统火山喷发

A Reinforcement Learning approach for the continuous electricity market ofGermany: Trading from the perspective of a wind park operator

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Energy and AI 2022年第2期8卷 67-78页

作者： Malte Lehna Björn Hoppmann christoph Scholz Renéheinrich Fraunhofer Institute for Energy Economics and Energy System Technology(IEE) Königstor 5934119 KasselGermany

With the rising extension of renewable energies, the intraday electricity markets have recorded a growingpopularity amongst traders as well as electric utilities to cope with the induced volatility of the energysupply. Through their short trading horizon and continuous nature, the intraday markets offer the abilityto adjust trading decisions from the day-ahead market or reduce trading risk in a short-term notice. Producersof renewable energies utilize the intraday market to lower their forecast risk, by modifying their providedcapacities based on current forecasts. However, the market dynamics are complex due to the fact that thepower grids have to remain stable and electricity is only partly storable. Consequently, robust and intelligenttrading strategies are required that are capable to operate in the intraday market. In this work, we proposea novel autonomous trading approach based on Deep Reinforcement Learning (DRL) algorithms as a possiblesolution. For this purpose, we model the intraday trade as a Markov Decision Process (MDP) and employ theProximal Policy Optimization (PPO) algorithm as our DRL approach. A simulation framework is introducedthat enables the trading of the continuous intraday price in a resolution of one minute steps. We test ourframework in a case study from the perspective of a wind park operator. We include next to general tradeinformation both price and wind forecasts. On a test scenario of German intraday trading results from 2018,we are able to outperform multiple baselines with at least 45.24% improvement, showing the advantage of theDRL algorithm. However, we also discuss limitations and enhancements of the DRL agent, in order to increasethe performance in future works.

关键词： Deep Reinforcement Learning German intraday electricity trading Deep neural networks Markov Decision Process Proximal Policy Optimization Electricity price forecast

Over-the-scope-clip closure of long lasting gastrocutaneous fistula after percutaneous endoscopic gastrostomy tube removal in immunocompromised patients:A single center case series

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World Journal of Gastrointestinal Endoscopy 2017年第2期9卷 85-90页

作者： Henriette heinrich christoph Gubler Piero V Valli Division of Gastroenterology and Hepatology University Hospital ZurichCH-8091 ZurichSwitzerland

Over-the-scope-clips (OTSC®) have been shown to be an effective and safe endoscopic treatment option for the closure of gastrointestinal perforations, leakages and fistulae. Indications for endoscopic OTSC® treatment have grown in number and also include gastro cutaneous fistula (GCF) after percutaneous endoscopic gastrostomy (PEG) tube removal. Non-healing GCF is a rare complication after removal of PEG tubes and may especially develop in immunosuppressed patients with multiple comorbidities. There is growing evidence in the literature that OTSC® closure of GCF after PEG tube removal is emerging as an effective, simple and safe endoscopic treatment option. However current evidence is limited to the geriatric population and short standing GCF, while information on closure of long standing GCF after PEG tube removal in a younger population with significant comorbidities is lacking. In this retrospective single-center case-series we report on five patients undergoing OTSC® closure of chronic GCF after PEG tube removal. Four out of five patients were afflicted with long lasting, symptomatic fistulae. All five patients suffered from chronic disease associated with a catabolic metabolism (cystic fibrosis, chemotherapy for neoplasia, liver cirrhosis). The mean patient age was 43 years. The mean dwell time of PEG tubes in all five patients was 808 d. PEG tube dwell time was shortest in patient 5 (21 d). The mean duration from PEG tube removal to fistula closure in patients 1-4 was 360 d (range 144-850 d). The intervention was well tolerated by all patients and no adverse events occured. Successful immediate and long-term fistula closure was accomplished in all five patients. This single center case series is the first to show successful endoscopic OTSC® closure of long lasting GCF in five consecutive middle-aged patients with significant comorbidities. Endoscopic closure of chronic persistent GCF after PEG tube removal

关键词： Gastro cutaneous fistula Endoscopic fistula closure Over-the-scope-clips Percutaneous endoscopic gastrostomy Fistula in immmunosuppressed patients

Selected gas response measurements using reduced graphene oxide decorated with nickel nanoparticles

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Nano Materials Science 2021年第4期3卷 412-419页

作者： Ilka Simon Yulyan Haiduk Rolf Mtilhaupt Vladimir Pankov christoph Janiak Institut für Anoganische Chemie und Strukturchemie heinrich-Heine Universität Düsseldorf 40204DüsseldorfGermany Chemical Faculty Belarusian State UniversityLenningradskaya Str.14220050 MinskBelarus Freiburg Materials Research Center and Institute for Macromolecular Chemistry Albert-Ludwigs-UniversityFreiburg79104FreiburgGermany

The work reports the synthesis of nickel nanoparticles supported on thermally reduced graphene oxides(rGO)in the ionic liquid[BMIm][NTf_(2)]through microwave decomposition ***@rGO with the polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)as binder was positively tested for its response towards the oxidizing gas nitrogen dioxide(10 ppm in air),the reducing gas carbon monoxide(3000 ppm in N_(2))and the volatile organic compound(VOC)acetone(35,000 ppm in air).The results from different gases were compared at different temperatures with the best results for NO_(2) at 200℃.Additionally,it is shown for NO_(2) gas that the Ni@rGO-PEDOT:PSS polymer composite gives better results than the rGO-PEDOT:PSS polymer *** the heat treatment the oxidation state of pure nickel nanoparticles were confirmed by powder diffraction.

关键词： Nickel nanoparticles Reduced graphene oxide Gas sensing Nanocomposite

Effects of six years of simulated N deposition on gross soil N transformation rates in an old-growth temperate forest

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Journal of Forestry Research 2018年第3期29卷 644-653页

作者： Peng Tian Jinbo Zhang christoph Müller Zucong Cai Guangze Jin College of Forestry Northeast Forestry UniversityHarbin 150040HeilongjiangPeople’s Republic of China School of Geography Sciences Nanjing Normal UniversityNanjing 210023People’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023People’s Republic of China Department of Plant Ecology(IFZ) Justus-Liebig University GiessenHeinrich-Buff-Ring 2635392 GiessenGermany School of Biology and Environmental Science University College DublinDublinIreland

Elevated atmospheric nitrogen(N) deposition has been detected in many regions of China, but its effects on soil N transformation in temperate forest ecosystems are not well known. We therefore simulated N deposition with four levels of N addition rate(N0, N30, N60, and N120) for6 years in an old-growth temperate forest in Xiaoxing’an Mountains in Northeastern China. We measured gross N transformation rates in the laboratory usingN tracing technology to explore the effects of N deposition on soil gross N transformations taking advantage of N deposition soils. No significant differences in gross soil N transformation rates were observed after 6 years of N deposition with various levels of N addition rate. For all N deposition soils, the gross NH~+ immobilization rates were consistently lower than the gross N mineralization rates,leading to net N mineralization. Nitrate(NO~-) was primarily produced via oxidation of NH~+(i.e., autotrophic nitrification), whereas oxidation of organic N(i.e., heterotrophic nitrification) was negligible. Differences between the quantity of ammonia-oxidizing bacteria and ammonia-oxidizing archaea were not significant for any treatment, which likely explains the lack of a significant effect on gross nitrification rates. Gross nitrification rates were much higher than the total NO~- consumption rates,resulting in a build-up of NO~-, which highlights the high risk of N losses via NO~- leaching or gaseous N emissions from soils. This response is opposite that of typical N-limited temperate forests suffering from N deposition,suggesting that the investigated old-growth temperate forest ecosystem is likely to approach N saturation.

关键词： N deposition Gross soil N transformation Temperate forest ecosystem ^(15)N tracing technology

Evaluation of acoustic radiation force impulse imaging for determination of liver stiffness using transient elastography as a reference

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World Journal of Gastroenterology 2012年第10期18卷 1077-1084页

作者： Gerald Kircheis Abdurrahman Sagir christoph Vogt Stephan vom Dahl Ralf Kubitz Dieter Hussinger Department of Gastroenterology Hepatology and Infectious Diseases Heinrich-Heine-University Düsseldorf Moorenstrasse 5 Düsseldorf 40225 Germany Christoph Vogt St. Josef Hospital Moers Asberger Str. 4 Moers 47441 Germany St. Franziskus Hospital Schnsteinstraβe 63 Kln 50825 Germany

AIM: To evaluate cut-off values and performance of acoustic radiation force impulse imaging (ARFI) using transient elastography [FibroScan■ (FS)] as a reference. METHODS: Six hundred and six patients were enrolled in this *** patients underwent liver stiffness measurement with FS (FS-LS) and ARFI (with shear wave velocity quantification; ARFI-SWV) and the performance of ARFI in comparison to FS was determined. Sixtyeight patients underwent liver biopsy. RESULTS: Significantly higher success rates for the determination of liver stiffness were found using ARFI as compared to FS [604/606 (99.7%) vs 482/606 (79.5%); P 13.0 kPa)). ARFI-SWV cut-off values were identified for no significant fibrosis (1.29 m/s; sensitivity 91.4% and specificity 92.6%) and for liver cirrhosis (1.60 m/s; sensitivity 92.3% and specificity 96.5%). The optimal cut-off value for predicting liver fibrosis (F ≥ 2) was 1.32 m/s (sensitivity 87.0% and specificity 80.0%) and for liver cirrhosis (F4) 1.62 m/s (sensitivity 100% and specificity 85.7%), for patients who underwent liver biopsy. An excellent inter-and intraobserver reproducibility was observed for ARFI-SWV determinations. CONCLUSION: An ARFI-SWV cut-off value of 1.29 m/s seems to be optimal for patients with no significant liver fibrosis and 1.60 m/s for patients with liver cirrhosis.

关键词： Acoustic radiation force impulse imaging Elastography Fibroscan Liver

Mitigating greenhouse gas emissions from croplands and pasturelands—climate-smart agriculture

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Pedosphere 2021年第2期31卷 227-230页

作者： Alberto SANZ-COBENA Weixin DING christoph MÜLLER Mohammad ZAMAN Lee HENG ETSI Agrónomos Universidad Politécnica de MadridCiudad UniversitariaMadrid 28040(Spain) Research Center for the Management of Environmental and Agricultural Risks(CEIGRAM) Universidad Politécnica de MadridCiudad UniversitariaMadrid 28040(Spain) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Institute of Plant Ecology Justus-Liebig University GiessenHeinrich-Buff-Ring 26Giessen 35392(Germany) School of Biology and Environmental Science and Earth Institute University College DublinDublin D04 V1W8(Ireland) Soil and Water Management&Crop Nutrition Section Joint FAO/IAEA DivisionInternational Atomic Energy AgencyVienna 1400(Austria)

One of the main challenges facing humankind is ensuring food security for a rapidly growing population with lower environmental footprints under changing climate. Environmental unsustainability of agro-food systems is multi-faced,but alteration of biogeochemical cycles (e.g., nitrogen (N)and phosphorus (P) cycles) and emissions of greenhouse gases (GHGs) to the atmosphere have been reported as one of the main disruptive forces over safe-operating space of planetary boundaries (Springmann et al., 2018).

关键词： N) phosphorus greenhouse

Effects of the nitrification inhibitor nitrapyrin and the plant growth regulator gibberellic acid on yield-scale nitrous oxide emission in maize fields under hot climatic conditions

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Pedosphere 2021年第2期31卷 323-331页

作者： Khadim DAWAR Kamil SARDAR Mohammad ZAMAN christoph MÜLLER Alberto SANZ-COBENA Aamir KHAN Azam BORZOUEI Ana Gabriela PÉREZ-CASTILLO Department of Soil and Environmental Science University of Agriculture PeshawarPeshawa 25000(Pakistan) Soil and Water Management&Crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria) Institute of Plant Ecology Justus Liebig UniversityHeinrich-Buff-Ring 26Giessen D-35392(Germany) School of Biology and Environmental Science University College DublinBelfieldD04 V1W8(Ireland) Management of Environment and Agricultural Risks(CEIGRAM) ETSIAABUniversidad Poliécnica de MadridMadrid 28040(Spain) Agricultural Research School Nuclear Science and Technology Research InstituteP.O.Box 31465/1498Karaj(Iran) Environmental Pollution Research Center(CICA) University of Costa RicaMontes de Oca 11501(Costa Rica)

Nitrification inhibitors are widely used in agriculture to mitigate nitrous oxide(N_(2)O)emission and increase crop ***,no concrete information on their mitigation of N_(2)O emission is available under soil and environmental conditions as in Pakistan.A field experiment was established using a silt clay loam soil from Peshawar,Pakistan,to study the effect of urea applied in combination with a nitrification inhibitor,nitrapyrin(2-chloro-6-tri-chloromethyl pyridine),and/or a plant growth regulator,gibberellic acid(GA_3),on N_(2)O emission and the nitrogen(N)uptake efficiency of *** experimental design was a randomized complete block with five treatments in four replicates:control with no N(CK),urea(200 kg N ha^(-1))alone,urea in combination with nitrapyrin(700 g ha^(-1)),urea in combination with GA_3(60 g ha^(-1)),and urea in combination with nitrapyrin and GA_*** N_(2)O emission,yield,N response efficiency,and total N uptake were measured during the experimental *** treatment with urea and nitrapyrin reduced total N_(2)O emission by 39%–43%and decreased yield-scaled N_(2)O emission by 47%–52%,relative to the treatment with urea *** maize plant biomass,grain yield,and total N uptake increased significantly by 23%,17%,and 15%,respectively,in the treatment with urea and nitrapyrin,relative to the treatment with urea alone,which was possibly due to N saving,lower N loss,and increased N uptake in the form of ammonium;they were further enhanced in the treatment with urea,nitrapyrin,and GA_3 by 27%,36%,and 25%,respectively,probably because of the stimulating effect of GA_3 on plant growth and development and the reduction in biotic and abiotic *** results suggest that applying urea in combination with nitrapyrin and GA_3 has the potential to mitigate N_(2)O emission,improve N response efficiency,and increase maize yield.

关键词： fertilizer use efficiency greenhouse gas emission mitigation N response efficiency N uptake efficiency N_(2)O flux plant growth hormone urea

sp^(3)-like defect structure of hetero graphene-carbon nanotubes for promoting carrier transfer and stability

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Journal of Energy Chemistry 2021年第6期30卷 189-197,I0005页

作者： Shan-Shan Fan Ling Shen Yuan Dong Ge Tian Si-Ming Wu Gang-Gang Chang christoph Janiak Ping Wei Jin-Song Wu Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Materials Science&EngineeringWuhan University of TechnologyWuhan 430070HubeiChina School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070HubeiChina Institut für Anorganische Chemie und Strukturchemie Heinrich-Heine-Universität Düsseldorf40204 DüsseldorfGermany NRC(Nanostructure Research Centre) Wuhan University of TechnologyWuhan 430070HubeiChina Department of Engineering and Applied Sciences Harvard University CambridgeMA 02138United States

Three-dimensional(3 D) hybrid of nanocarbons is a very promising way to the high-performance design of electrocatalysis ***,sp^(3)-like defect structure,a combination of high strength and conduction of graphene and carbon nanotubes(CNTs) is rarely ***,3 D neural-like hybrids of graphene(from reduced graphene oxide) and carbon nanotubes(CNTs) have been integrated via sp^(3)-like defect structure by a hydrothermal *** sp^(3)-like defect structure endows 3 D nanocarbon hybrids with an enhanced carrier transfer,high structural stability,and electrocatalytic *** neural-like structure is shown to demonstrate a cascade effect of charges and significant performances regarding bio-electrocatalysis and lithium-sulfur energy *** concept and mechanism of "sp^(3)-like defect structure" are proposed at an atomic/nanoscale to clarify the generation of rational structure as well as the cascade electron transfer.

关键词： Graphene Carbon nanotubes sp^(3)-like defect structure Bio-electrocatalysis Lithium-sulfur batteries

Nitrification inhibitor nitrapyrin does not affect yield-scaled nitrous oxide emissions in a tropical grassland

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Pedosphere 2021年第2期31卷 265-278页

作者： Ana Gabriela PÉREZ-CASTILLO Cristina CHINCHILLA-SOTO Jorge Alberto ELIZONDO-SALAZAR Ronny BARBOZA Dong-Gill KIM christoph MÜLLER Alberto SANZ-COBENA Azam BORZOUEI Khadim DAWAR Mohammad ZAMAN Environmental Pollution Research Center(CICA) University of Costa RicaMontes de Oca 11501(Costa Rica) Alfredo Volio Mata Experimental Station University of Costa RicaOchomogo 30304(Costa Rica) Wondo Genet College of Forestry and Natural Resources Hawassa UniversityP.O.Box 128Shashemene(Ethiopia) Institute of Plant Ecology Justus Liebig University GiessenHeinrich-Buff Ring 26Giessen 35392(Germany) School of Biology and Environmental Science University College DublinBelfieldDublin 4(Ireland) Research Center for the Management of Environmental and Agricultural Risks(CEIGRAM) Department of Chemistry and Food Technology(ETSIAAB)Universidad Politécnica de MadridMadrid 28040(Spain) Nuclear Agriculture Research School Nuclear Science and Technology Research Institute(NSTRI)Karaj 31465-1498(Iran) Department of Soil and Environmental Sciences The University of AgriculturePeshawar 25000(Pakistan) Soil and Water Management&Crop Nutrition Section Joint Food and Agriculture Organization(FAO)/International Atomic Energy Agency(IAEA)Division of Nuclear Techniques in Food and AgricultureDepartment of Nuclear Sciences and ApplicationsIAEAVienna International CentreP.O.Box 100Vienna 1400(Austria)

Urea is the most common nitrogen(N)fertilizer used in the tropics but it has the risk of high gaseous nitrogen(N)*** of nitrification inhibitor has been suggested as a potential mitigation measure for gaseous N losses in N fertilizer-applied *** a field trial on a tropical Andosol pastureland in Costa Rica,gaseous emissions of ammonia(NH_(3))and nitrous oxide(N_(2)O)and grass yield were quantified from plots treated with urea(U;41.7 kg N ha^(-1)application^(-1))and urea plus the nitrification inhibitor nitrapyrin(U+NI;41.7 kg N ha^(-1)application^(-1)and 350 g of nitrapyrin for each 100 kg of N applied)and control plots(without U and NI)over a six-month period(rainy season).Volatilization of NH_(3)(August to November)in U(7.4%±1.3%of N applied)and U+NI(8.1%±0.9%of N applied)were not significantly different(P>0.05).Emissions of N_(2)O in U and U+NI from June to November were significantly different(P<0.05)only in October,when N_(2)O emission in U+NI was higher than that in *** and crude protein production of grass were significantly higher(P<0.05)in U and U+NI than in the control plots,but they were not significantly different between U and U+*** was no significant difference in yield-scaled N_(2)O emission between U(0.31±0.10 g N kg^(-1)dry matter)and U+NI(0.47±0.10 g N kg^(-1)dry matter).The results suggest that nitrapyrin is not a viable mitigation option for gaseous N losses under typical N fertilizer application practices of pasturelands at the study site.

关键词： ammonia volatilization Andosol Costa Rica field trial gaseous N loss greenhouse gas emission urea