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Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy

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Journal of Renewable Materials 2023年第4期11卷 1643-1660页

作者： Tobias Drieschner Andreas Kandelbauer bernd Hitzmann Karsten Rebner Lehr-und Forschungszentrum Process Analysis and Technology(PA&T)der Hochschule Reutlingen Reutlingen72762Germany Department of Process Analytics and Cereal Science Institute of Food Science and BiotechnologyUniversität HohenheimStuttgart70599Germany

For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is ***,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and *** present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor *** this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are *** optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction *** quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares *** data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of ***,we applied a PAT approach to generate further insight into this established industrial process.

关键词： Process analytical technology transesterification design of experiment attenuated total reflection infrared spectroscopy partial least square regression

Prediction of the biogas production using GA and ACO input features selection method for ANN model

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Information Processing in Agriculture 2019年第3期6卷 349-356页

作者： Tanja Beltramo Michael Klocke bernd Hitzmann Institute of Food Science and Biotechnology University of HohenheimStuttgart 70599Germany Leibniz Institute for Agricultural Engineering and Bioeconomy Potsdam 14469Germany

This paper presents a fast and reliable approach to analyze the biogas production process with respect to the biogas production *** experimental data used for the developed models included 15 process variables measured at an agricultural biogas plant in *** this context,the concentration of volatile fatty acids,total solids,volatile solids acid detergent fibre,acid detergent lignin,neutral detergent fibre,ammonium nitrogen,hydraulic retention time,and organic loading rate were *** neural networks(ANN)were established to predict the biogas production *** ant colony optimization and genetic algorithms were implemented to perform the variable *** identified the significant process variables,reduced the model dimension and improved the prediction capacity of the ANN *** best prediction of the biogas production rate was obtained with an error of prediction of 6.24%and a coefficient of determination of R2=0.9.

关键词： Ant colony optimization Artificial neural networks Biogas Genetic algorithm

Reaction mechanism of hydrogen activation by frustrated Lewis pairs

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Green Energy & Environment 2019年第1期4卷 20-28页

作者： Lei Liu Binit Lukose Pablo Jaque bernd Ensing Department of Physics & Earth Sciences Jacobs University Max Planck Institute for Polymer Research School of Electrical and Computer Engineering Boston University Department of Organic and Physical Chemistry Faculty of Chemical and Pharmaceutical Sciences University of Chile Van't Hoff Institute for Molecular Sciences University of Amsterdam

Typically, a Lewis acid and a Lewis base can react with each other and form a classical Lewis adduct. The neutralization reaction can however be prevented by ligating the acid and base with bulky substituents and the resulting complex is known as a "frustrated Lewis pair"(FLP). Since the Lewis acid and base reactivity remains in the formed complex, FLPs can display interesting chemical activities, with promising applications in catalysis. For example, FLPs were shown to function as the first metal-free catalyst for molecular hydrogen activation. This, and other recent applications of FLPs, have opened a new thriving research field. In this short-review, we recapitulate the computational and experimental studies of the H_2 activation by FLPs. We discuss the thus-far uncovered mechanistic aspects, including pre-organization of FLPs,the reaction paths for the activation, the polarization of He H bond and other factors affecting the reactivity. We aim to provide a rather complete mechanistic picture of the H_2 activation by FLPs, which has been under debate for decades since the first discovery of FLPs. This review is meant as a starting point for future studies and a guideline for industrial applications.

关键词： Frustrated Lewis pairs Hydrogen activation Reaction mechanisms Density functional theory Molecular dynamics simulations

The effect of hydrogen bond acceptor properties of ionic liquids on their cellulose solubility

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Science China Chemistry 2012年第8期55卷 1663-1670页

作者： STARK Annegret SELLIN Martin ONDRUSCHKA bernd MASSONNE Klemens Institute of Chemical Technology University of Leipzig Linnéstr. 3-4 04107 Leipzig Germany Thuringian Institute of Textile and Plastics Research Breitscheidstr. 97 07407 Rudolstadt-Schwarza Germany Institute for Technical Chemistry and Environmental Chemistry Friedrich-Schiller-University Lessingstr. 12 07743 Jena Germany BASF SE Chemical Research & Engineering 67056 Ludwigshafen Germany

It is nowadays well-known that ionic liquids can dissolve cellulose. However, little systematic data has been published that shed light onto the influence of the ionic liquid structure on the dissolution of cellulose. We have conducted 1H NMR spec- troscopy of ethanol in a large number of ionic liquids, and found an excellent correlation of the data obtained with the hydro- gen acceptor properties （B-values）. With this tool in hand, it is possible to distinguish between cellulose-dissolving and non-dissolving ionic liquids. A modulating effect of both, the anion of the non-dissolving ionic liquid and its cation was found in solubility studies with binary ionic liquid mixtures. The study was extended to other non-dissolving liquids, namely water and dimethylsulfoxide, and the effect of the cation was also investigated.

关键词： ionic liquids cellulose dissolution hydrogen bonding

MRBLES 2.0: High-throughput generation of chemically functionalized spectrally and magnetically encoded hydrogel beads using a simple single-layer microfluidic device

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Microsystems & Nanoengineering 2020年第1期6卷 145-157页

作者： Yinnian Feng Adam K.White Jamin B.Hein Eric A.appel Polly M.Fordyce Department of Genetics Stanford UniversityStanfordCA 94305USA Department of Bioengineering Stanford UniversityStanfordCA 94305USA Department of Biology Stanford UniversityStanfordCA 94305USA The Novo Nordisk Foundation Center for Protein Research Faculty of Health and Medical SciencesUniversity of CopenhagenBlegdamsvej 3b2200 CopenhagenDenmark Department of Materials Science&Engineering Stanford UniversityStanfordCA 94305USA Stanford ChEM-H Stanford UniversityStanfordCA 94305USA Chan Zuckerberg Biohub San FranciscoCA 94110USA

The widespread adoption of bead-based multiplexed bioassays requires the ability to easily synthesize encoded microspheres and conjugate analytes of interest to their ***,we present a simple method(MRBLEs 2.0)for the efficient high-throughput generation of microspheres with ratiometric barcode lanthanide encoding(MRBLEs)that bear functional groups for downstream surface *** production in MRBLEs 2.0 relies on the manual mixing of lanthanide/polymer mixtures(each of which comprises a unique spectral code)followed by droplet generation using single-layer,parallel flow-focusing devices and the off-chip batch polymerization of droplets into *** streamline downstream analyte coupling,MRBLEs 2.0 crosslinks copolymers bearing functional groups on the bead surface during bead *** the MRBLEs 2.0 pipeline,we generate monodisperse MRBLEs containing 48 distinct well-resolved spectral codes with high throughput(>150,000/min and can be boosted to 450,000/min).We further demonstrate the efficient conjugation of oligonucleotides and entire proteins to carboxyl MRBLEs and of biotin to amino ***,we show that MRBLEs can also be magnetized via the simultaneous incorporation of magnetic nanoparticles with only a minor decrease in the potential code *** the advantages of dramatically simplified device fabrication,elimination of the need for custom-made equipment,and the ability to produce spectrally and magnetically encoded beads with direct surface functionalization with high throughput,MRBLEs 2.0 can be directly applied by many labs towards a wide variety of downstream assays,from basic biology to diagnostics and other translational research.

关键词： beads spectral functional

Effects of urbanization on heavy metal accumulation in surface soils, Beijing

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Journal of Environmental Sciences 2018年第2期30卷 328-334页

作者： Meie Wang Rui Liu Weiping Chen Chi Peng bernd Markert State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Environmental Institute of Scientific Networks 49733 Haren Germany

Urbanization processes affect the accumulation of heavy metals in urban soils. Effects of urbanization on heavy metal accumulation in soils were studied using Beijing as an example. It has been suggested that the ecological function of vegetation covers shifting from natural to agricultural settings and then to urban greenbelts could increase the zinc（Zn） concentrations of soils successively. The Zn concentration of urban soils was significantly correlated to the percentage of the impervious land surface at the500 m × 500 m spatial scale. For urban parks, the age or years since the development accounted for 80% of the variances of cadmium（Cd） and Zn in soils. The population density,however, did not affect the heavy metal distributions in urban soils. To conclude, the urban age turned out to be a notable factor in quantifying heavy metal accumulation in urban soils.

关键词： Urban soils Human disturbance Zn Impervious land Population density

Immunobiology and immunotherapy of HCC:spotlight on innate and innate-like immune cells

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Cellular & Molecular Immunology 2021年第1期18卷 112-127页

作者： Benjamin Ruf bernd Heinrich Tim F.Greten Gastrointestinal Malignancy Section Thoracic and Gastrointestinal Malignancies BranchCentre for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesdaMD 20892USA NCI CCR Liver Cancer Program National Institutes of HealthBethesdaMD 20892USA

Immune-based therapies such as immune checkpoint inhibitors have revolutionized the systemic treatment of various cancer *** therapeutic application of monoclonal antibodies targeting inhibitory pathways such as programmed cell death-1(PD-1)/programmed cell death ligand 1(PD-L1)and CTLA-4 to cells of the adaptive immune system has recently been shown to generate meaningful improvement in the clinical outcome of hepatocellular carcinoma(HCC).Nevertheless,current immunotherapeutic approaches induce durable responses in only a subset of HCC *** immunologic mechanisms such as chronic inflammation due to chronic viral hepatitis or alcoholic and nonalcoholic fatty liver disease play a crucial role in the initiation,development,and progression of HCC,it is important to understand the underlying mechanisms shaping the unique tumor microenvironment of liver *** liver is an immunologic organ with large populations of innate and innate-like immune cells and is exposed to bacterial,viral,and fungal antigens through the gut-liver ***,we summarize and highlight the role of these cells in liver cancer and propose strategies to therapeutically target *** also discuss current immunotherapeutic strategies in HCC and outline recent advances in our understanding of how the therapeutic potential of these agents might be enhanced.

关键词： HCC immunotherapy innate immunity tumor microenvironment

Pervasive geo-security - a lightweight triple-A approach to securing distributed geo-service infrastructures

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International Journal of Digital Earth 2014年第5期7卷 373-390页

作者： bernd Resch Bernhard Schulz Manfred Mittlboeck Thomas Heistracher Research Studio iSPACE Research Studios AustriaSalzburgAustria SENSEable City Laboratory Massachusetts Institute of TechnologyBostonMAUSA Department of Information Technology and Systems Management University of Applied SciencesSalzburgAustria

Security has recently become a major concern in distributed geo-infrastructures for spatial data ***,a lightweight approach for securing distributed low-power environments such as geo-sensor networks is *** first part of this article presents a survey of current security mechanisms for authentication and *** on this survey,a lightweight and scalable token-based security infrastructure was developed,which is tailored for use in distributed geo-web service *** developed security framework comprises dedicated components for authentication,rule-based authorisation and optimised storage and administration of access *** validation purposes,a prototypical implementation of the approach has been created.

关键词： pervasive security distributed geo-service infrastructures triple-A geo-authorisation standardised sensor networks service protection Geographic Information Systems(GIS) geoinformatics spatial data infrastructure Digital Earth Digital Earth Architecture

Oxygen tolerance capacity of upflow anaerobic solid-state(UASS) with anaerobic filter(AF) system

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Journal of Environmental Sciences 2016年第7期28卷 200-206页

作者： Yao Meng Carsten Jost Jan Mumme Kaijun Wang bernd Linke State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Department Bioengineering Leibniz Institute for Agricultural Engineering UK Biochar Centre School of Geo Sciences University of Edinburgh

In order to investigate the oxygen tolerance capacity of upflow anaerobic solid-state（UASS）with anaerobic filter（AF） system, the effect of microaeration on thermophilic anaerobic digestion of maize straw was investigated under batch conditions and in the UASS with AF system. Aeration intensities of 0–431 m L O2/gvswere conducted as pretreatment under batch conditions. Aeration pretreatment obviously enhanced anaerobic digestion and an aeration intensity of 431 m L O2/gvsincreased the methane yield by 82.2%. Aeration intensities of 0–355 m L O2/gvswere conducted in the process liquor circulation of the UASS with AF system. Dissolved oxygen（DO） of UASS and AF reactors kept around 1.39 ±0.27 and 0.99 ± 0.38 mg/L, respectively. p H was relatively stable around 7.11 ± 0.04. Volatile fatty acids and soluble chemical oxygen demand concentration in UASS reactor were higher than those in AF reactor. Methane yield of the whole system was almost stable at 85 ± 7 m L/gvs as aeration intensity increased step by step. The UASS with AF system showed good oxygen tolerance capacity.

关键词： Anaerobic digestion Oxygen tolerance capacity UASS Maize straw Microaeration Solid-state