Miracle-dz/UniFAR-FTUs huggingface dataset:
Highly Sensitive Glucose Biosensors Based on Organic Electrochemical Transistors Using Platinum Gate Electrodes Modified with Enzyme and Nanomaterials

Organic electrochemical transistors with glucose oxidase‐modified Pt gate electrodes are successfully used as highly sensitive glucose sensors. The gate electrodes are modified with nanomaterials (multi‐wall carbon nanotubes or Pt nanoparticles) for the first time, which results in a dramatic improvement in the sensitivity of the devices. The detection limit of the device modified with Pt nanoparticles on the gate electrode is about 5 nM, which is three orders of magnitude better than a device without the nanoparticles. The improvement of the device performance can be attributed to the excellent electrocatalytic properties of the nanomaterials and more effective immobilization of enzyme on the gate electrodes. Based on the same principle, many other types of enzyme sensors with high sensitivity and low cost are expected to be realized by modifying the gate electrodes of organic electrochemical transistors with specific enzymes and nanomaterials.
Dichtefunktional-Rechnungen zu selektiven Oxidationen von Propan und Methanol mittels Vanadiumoxidkatalysatoren auf Siliziumdioxidträgern

In this work cluster models and models for QM/MM-embedding for supported vanadia catalysts on silica were studied with help of DFT-calculations. The structures, vibrations and stability towards water and oxygen under reaction conditions were examined. Furthermore the reactivities towards the oxidative dehydrogenation (ODH) of n-propane to n-propene and the oxidation of methanol to formaldehyde were tested. For the embedding an adapted shell-model-potential was employed. Regarding the vibrations it was shown that the influence of the embedding lies mostly in the coupling of vibrations and not in their frequencies. The local structure surrounding the vanadium atom has only minor influence. The stability calculations have shown that the tested model systems exist under reaction conditions while hydroxylated species do not exist. When studying the reactivity of the two reactions always the same mechanism is found for cluster and embedded calculations. The benefit of the embedded calculations is the possibility to vary the local structure surrounding the active center. For the ODH of propane the local structure has only small impact on reaction energies because the reaction takes mainly place at the vanadyl oxygen. The transition state of the rate determining step nevertheless is energetically higher in the embedded calculations due to steric hindrance caused by the hydroxyl groups of the surface. The impact of local structure is more important for the oxidation of methanol since in this case vanadyl oxygen and bridging oxygens to the support are involved in the reaction. For both reactions an influence on reaction energies of the vanadia loading is found. With more loading the reactions becomes more exothermic.
Grain Boundary Diffusion in Cation-Doped Superplastic 3Y-TZP

The superplastic flow in tetragonal zirconia polycrystals stabilised 3mol% Y2O3 (3YTZP) is strongly affected by the dopant cations, which segregate at the grain boundary. It is proposed that this flow is controlled by grain boundary diffusion of Zr4+ ions and therefore the dopant cations should change the grain boundary diffusion. In order to prove this thesis the measurements of grain boundary diffusion coefficients were made using Hf4+ ions as tracer. Zirconia samples were doped with 1mol% of Al2O3, SiO2, MgO, MgAl2O4, GeO2 and TiO2. The tracer was deposited on the surface of the zirconia specimens by placing several drops of hafnium nitrate and then drying at 373 K. In this way, thin films of HfO 2 were obtained. The samples were heated in the range 1553 – 1773 K for 1 to 24 h. The concentration versus depth profiles were measured using secondary ion mass spectrometry (SIMS). Calculated hence grain boundary diffusion coefficients were several times bigger for doped samples than for pure 3Y-TZP samples.
Effect of Surfactant Layers on the Size Changes of Aerosol Particles as a Function of Relative Humidity

We present water sorption/desorption curves for NaCl and carbon black particles coated with individual organic surfactants. The surfactants used in this study were Tween 80 (a polyoxyethylene sorbitan ester and nonionic surfactant), dodecyl sulfate, sodium salt (an anionic surfactant), and azelaic acid (an organic surfactant). The sorption curves show the change in mass of the coated particles as a function of relative humidity and were determined using an electrodynamic particle balance. Our results show that a Tween 80 coating on a NaCl particle lowers the deliquescence relative humidity from 75% for an uncoated NaCl particle to 70-73%, depending on the thickness of the coating. Another effect of the coating is a decrease in the maximum relative mass gain (M/M[sub 0]) at the deliquescence point. M/M[sub 0] ranges from 4.0 to 4.1 for the uncoated NaCl particle while M/M[sub 0] for the coated NaCl particle ranges between 1.75 and 3.5, again depending on the thickness of the coating. For the carbon black/surfactant systems, our results suggest that while uncoated carbon black particles are hydrophobic, a surfactant coating on carbon black particles increases the hygroscopicity of the carbon black particles. Carbon particles coated with Tween 80 showed a relative mass gain ofmore » 1.2 at 90% relative humidity; carbon particles coated with dodecyl sulfate, sodium salt showed a relative mass gain of 1.1-1.2 at 90% relative humidity; and carbon particles coated with azelaic acid showed a relative mass gain of 1.4 at 86% relative humidity. 43 refs., 8 figs., 3 tabs. « less
Morphology and Adsorbate Dependence of Ionic Transport in Dye Sensitized Mesoporous TiO2 Films

By modeling the steady-state mass transport in a thin-layer cell configuration involving an electrochemically inactive mesoporous colloidal film, the limiting currents of an iodine containing electrolyte can be predicted, as a function of the film porosity. The porosity of the layer is then determined by best fit of the porosity parameter in the model, given the experimentally determined limiting currents. Satisfactory agreement is found with the porosity values obtained by BET measurements. In photoelectrochemical cell applications such as dye sensitized nanocrystalline photoelectrodes for solar energy conversion devices, the porosities of the dye loaded films of e.g. anatase TiO2 play an essential role with respect to their efficiency. In particular, the findings of this work demonstrate that the presence of adsorbed sensitizer cis-(SCN-)2 bis(2,2‘-bipyridyl-4,4‘-dicarboxylate)ruthenium(II) in TiO2 colloidal films appears to decrease the original naked film porosity by up to 30%. This depends on the ini.
A Gold Nanoparticle‐Based Aptamer Target Binding Readout for ATP Assay

A gold nanoparticle-based detection strategy for ATP assays. In the absence of ATP, gold nanoparticles are not stabilized by the rigid duplex, thus they are readily aggregated by salt (solution displaying blue colors); in contrast induces a duplex-to-aptamer structural switching, liberating a random coil-like ssDNA. Gold nanoparticles are stabilized by the liberated ssDNA, showing high resistance to salt-induced aggregation (solution staying in red).
Effect of Clay Minerals and Organic Matter Injection in El-Salhia Soil on Water Use Efficiency of Cucumber

The sandy soil in arid area is comparatively poorly character and their physical and chemical properties are very low. Therefore, the irrigation water loaded with mineral fertilizer is lost by deep leakage. Some authors reported that the clay amendments are highly effective in improving the physical and chemical properties of these soils and hence increased their fertility and productivity. Clay amendment in sandy soil increases fertility with the essential macroand micronutrients when bentonite percentage in sandy soils is more than 5% (Karbout et al., 2015). Sandy soils have low cation exchange capacity (CEC), therefore low nutrient retention capacity and organic matter content Walpola and Arunakumara (2010) and low water holding capacity resulting in low yield. Clay-rich soils on the other hand, have high CEC as well as high water and nutrient retention capacity (Hamarashid et al., 2010). On the other hand, the Bentonite ore often contains more than 75% of Montmorillonite mineral. Bentonite swelled extremely when exposed to water, labour it perfect for conserving formations from overrun by dig fluids. Sodium Bentonite achieved specifications the dig-clay F experiments were performed during two summer successive seasons of 2017 and 2018, at a private farm in ElSalhia El-Gedida area, ElSharqia Governorate, Egypt, to determine the best treatment of sandy soil injection with different rates, from clay and humic acids additive through different doses. In addition to studying the effect of injecting sandy soil by clay and humic acids (IS), different irrigation water levels (IR=100, 90, 80, 70, 60, 50 and 40% calculated based on crop evapotranspiration) and three mineral fertilizer rates (MFR=100, 70 and 40% of recommended chemical fertilizer N, P, K rates) on the marketable yield (MY), crop quality parameters, seasonal actual evapotranspiration (ETa), water use efficacy (WUE) and irrigation water use efficiency (IWUE) for summer cucumber fruits “Cucumis sativus” were investigated. The results reported that; 1) the marketable yield and studied quality parameters except total soluble solid (TSS) and vitamin C (VC) of summer cucumber fruits gave the highest values under IS, IR and MFR =100% treatments for both seasons. 2) Seasonal ETa gave the lowest values: 155.01 and 142.23 mm for both seasons, respectively, under IS, IR and MFR= 40% treatments. 3) The maximum values of summer cucumber fruits WUE and IWUE were 22.03 and 16.63 kg/m; 26.34 and 18.12 kg/m for both seasons, respectively, under IS, IR=60% and MFR=70% treatment. This study concluded that the cultivation of summer cucumber under IS, IR= 60% and MFR= 70% treatment can possibly save about 40% of the applied irrigation water, 30% of the total mineral fertilizers rates additive and increased marketable yield of the summer cucumber fruit about 27 and 36% for both seasons, respectively, compared with that under the control treatment (UIS, IR=100% and MFR=100%).
Application of Steenbeck's minimum principle for three-dimensional modelling of DC arc plasma torches

In this paper, physical/mathematical models for the three-dimensional, quasi-steady modelling of the plasma flow and heat transfer inside a non-transferred DC arc plasma torch are described in detail. The Steenbeck's minimum principle (Finkelnburg W and Maecker H 1956 Electric arcs and thermal plasmas Encyclopedia of Physics vol XXII (Berlin: Springer)) is employed to determine the axial position of the anode arc-root at the anode surface. This principle postulates a minimum arc voltage for a given arc current, working gas flow rate, and torch configuration. The modelling results show that the temperature and flow fields inside the DC non-transferred arc plasma torch show significant three-dimensional features. The predicted anode arc-root attachment position and the arc shape by employing Steenbeck's minimum principle are reasonably consistent with experimental observations. The thermal efficiency and the torch power distribution are also calculated in this paper. The results show that the thermal efficiency of the torch always ranges from 30% to 45%, i.e. more than half of the total power input is taken away by the cathode and anode cooling water. The special heat transfer mechanisms at the plasma–anode interface, such as electron condensation, electron enthalpy and radiative heat transfer from the bulk plasma to the anode inner surface, are taken into account in this paper. The calculated results show that besides convective heat transfer, the contributions of electron condensation, electron enthalpy and radiation to the anode heat transfer are also important (~30% for parameter range of interest in this paper). Additional effects, such as the non-local thermodynamic equilibrium plasma state near the electrodes, the transient phenomena, etc, need to be considered in future physical/mathematical models, including corresponding measurements.
Enantioselective solid phase extraction prior to spectrofluorometric determination: a procedure for the determination of naproxen enantiomers in the presence of each other

A method for the simultaneous spectrofluorometric determination of naproxen drug enantiomers has been proposed. The method is based on three procedures. These procedures have their precision limitation which has been fully investigated and the optimized condition has been proposed. In this regard, magnetite nanospheres have been chemically modified with L-(−)-tryptophan (Try-MNSs). The synthesized nanospheres have been characterized by FT-IR, XRD, VSM and TEM measurements. The results showed that Try-MNSs have good enantioselectivity toward S-(+)-Naproxen and could efficiently remove it in the presence of its enantiomer. Using the proposed procedures, precise naproxen drug enantiomeric composition analysis in a concentration range of 100.0–1800.0 ng mL−1 is achievable. Furthermore, S-(+)-Naproxen determination in a 2.0–50.0 ng mL−1 concentration range with a detection limit of 0.7 ng mL−1 is feasible.
Die Veränderung fachbezogener Vorstellungen angehender Chemielehrkräfte über Unterricht während der Ausbildung – eine Cross‐Level Studie

In einer Cross-Level Studie wurden Vorstellungen angehender Lehrkrafte der Chemie uber das Lehren und Lernen zu verschiedenen Zeitpunkten ihrer Ausbildung erhoben. Genutzt wurden Zeichnungen von Studierenden und Referendaren einer fur sie typischen Unterrichtssituation. Ausgewertet wurden diese mit einem Kodierschema, das uber Grounded Theory entwickelt und inzwischen in verschiedenen Studien verwendet worden ist. Auswertungskategorien waren: Vorstellungen uber die Organisation im Klassenraum, Vorstellungen uber die Lernziele und epistemologische Vorstellungen. Verglichen wurden drei Stichproben von zukunftigen Lehrkraften am Anfang ihres Studiums, in der Mitte des Studiums nach einem Praxissemester und wahrend des Referendariats. Der Vergleich legt die Moglichkeit eines grundlegenden Wandels der Vorstellungen uber Unterricht wahrend der Ausbildung nahe. Von sehr traditionellen und lehrerzentrierten Sichtweisen konnen sich die Vorstellungen hin zu starker theoriekonformen Vorstellungen wandeln, angelehnt an Schulerorientierung und konstruktivistisches Lernen. This paper presents a cross-level study on prospective chemistry teachers' beliefs about teaching and learning at different stages of their pre-service training. The study is based upon drawings of teaching situations made by university student teachers and post-university teachers in training. The drawings were analyzed using an evaluation grid developed by Grounded Theory and applied so far in different studies. Categories for evaluation were: beliefs about classroom organization, teaching objectives, and epistemology. The study compares three different groups of prospective teachers: freshman student teachers, student teachers in the middle of their university studies having had a half-year internship in school, and teachers in training from the compulsory post-university training (‘Referendariat’). The comparison indicates that a substantial change in the beliefs about teaching and learning during the teacher education is possible. Beliefs can change from very traditional and teacher-centered beliefs in the beginning, towards modern educational beliefs based on student-orientation and constructivist learning.
Effect of temperature and storage period of olive (Olea europaea cv. Zard) fruit on olive oil quality

Black-ripe olive (Olea europaea cv. Zard) fruits, harvested from trees grown in Tarom (Zanjan) climatic conditions, were stored in 92±2% humidity and three different temperatures (5°C, 8°C and 20°C) for six different periods of 5, 10, 15, 20, 25 and 30 days. Evaluations were made on parameters such as flesh firmness, weight loss, chilling injury and fungus development during storage and relative oil quality. Oils were extracted immediately after fruit harvest and at the end of six predetermined temporal storage periods. Acidity, peroxide value and total polyphenol content were analyzed in each single treatment together with sensorial quality determined for 30 days. The results confirmed that olives stored at 5°C even for 30 days maintained initial sensorial, visual and chemical qualities and at 8°C the quality was maintained for 25 days while olives stored at room temperature led to deterioration only after 5 days of storage.
Compilation of Gas Intrusion Measurements, Variations, and Consequence Modeling for SPR Caverns

The intrusion of gas into oils stored within the SPR has been examined. When oil is stored in domal salts, gases intrude into the stored oil from the surrounding salt. Aspects of the mechanism of gas intrusion have been examined. In all cases, this gas intrusion results in increases in the oil vapor pressure. Data that have been gathered from 1993 to August 2002 are presented to show the resultant increases in bubble-point pressure on a cavern-by-cavern as well as on a stream basis. The measurement techniques are presented with particular emphasis on the TVP 95. Data analysis methods are presented to show the methods required to obtain recombined cavern oil compositions. Gas-oil ratios are also computed from the data and are presented on a cavern-by-cavern and stream basis. The observed increases in bubble-point pressure and gas-oil ratio are further statistically analyzed to allow data interpretation. Emissions plume modeling is used to determine adherence to state air regulations. Gas intrusion is observed to be variable among the sites and within each dome. Gas intrusions at Bryan Mound and Big Hill have resulted in the largest increases in bubble-point pressure for the Strategic Petroleum Reserve (SPR). The streams at Bayou Choctaw and West Hackberry show minimal bubble-point pressure increases. Emissions plume modeling, using the state mandated ISCST code, of oil storage tanks showed that virtually no gas may be released when H2S standards are considered. DOE plans to scavenge H{sub 2}S to comply with the very tight standards on this gas. With the assumption of scavenging, benzene releases become the next most controlling factor. Model results show that a GOR of 0.6 SCF/BBL may be emissions that are within standards. Employing the benzene gas release standard will significantly improve oil deliverability. New plume modeling using the computational fluid dynamics code, FLUENT, is addressing limitations of the state mandated ISCST model.
Electrolytic Generation of Ozone on an Antimony-Doped Tin Dioxide Coated Electrode

Dissolved ozone up to 34 mg/L was generated by direct electrolysis of water using a titanium electrode coated with an antimony-doped tin dioxide film. The electrode was prepared by spray pyrolysis at 520°C. The current efficiency of ozone generation was 15% in a 0.1 M HClO 4 aqueous solution at room temperature. The electrolytic generation of ozone depends critically on the composition and morphology of the coating and a good generation was observed with Sb:Sn atomic ratio of 1:7 and a smooth and compact surface with connected particles of 3-5 nm diameter.
Application of Permanent Dry High Intensity Magnetic Separation for the Processing of Spent FCC Catalyst

This paper discusses the application of permanent dry high intensity magnetic separation to improve the efficiency of Fluidised Catalytic Cracking (FCC) systems used in oil refining, causing preferential removal of deactivated (spent) catalyst from the process. It was shown that this technique can provide efficient separation of spent catalyst from fresh, despite some loss of fine particles. The effects of particle segregation were also investigated, with both magnetic and nonmagnetic particles. Separation was found to be particularly good for material above 90gm, but efficiency decreased below this particle size. The paper concludes with recommendations for the implementation of the technology.
Skeletonization and Segmentation of Binary Voxel Shapes

Preface. This dissertation is the result of research that I conducted between January 2005 and December 2008 in the Visualization research group of the Technische Universiteit Eindhoven. I am pleased to have the opportunity to thank a number of people that made this work possible. I owe my sincere gratitude to Alexandru Telea, my supervisor and first promotor. I did not consider pursuing a PhD until my Master’s project, which he also supervised. Due to our pleasant collaboration from which I learned quite a lot, I became convinced that becoming a doctoral student would be the right thing to do for me. Indeed, I can say it has greatly increased my knowledge and professional skills. Alex, thank you for our interesting discussions and the freedom you gave me in conducting my research. You made these four years a pleasant experience. I am further grateful to Jack vanWijk, my second promotor. Our monthly discussions were insightful, and he continuously encouraged me to take a more formal and scientific stance. I would also like to thank Prof. Jan de Graaf from the department of mathematics for our discussions on some of my conjectures. His mathematical rigor was inspiring. I am greatly indebted to the Netherlands Organisation for Scientific Research (NWO) for funding my PhD project (grant number 612.065.414). I thank Prof. Kaleem Siddiqi, Prof. Mark de Berg, and Dr. Remco Veltkamp for taking part in the core doctoral committee and Prof. Deborah Silver and Prof. Jos Roerdink for participating in the extended committee. Our Visualization group provides a great atmosphere to do research in. In particular, I would like to thank my fellow doctoral students Frank van Ham, Hannes Pretorius, Lucian Voinea, Danny Holten, Koray Duhbaci, Yedendra Shrinivasan, Jing Li, NielsWillems, and Romain Bourqui. They enabled me to take my mind of research from time to time, by discussing political and economical affairs, and more trivial topics. Furthermore, I would like to thank the senior researchers of our group, Huub van de Wetering, Kees Huizing, and Michel Westenberg. In particular, I thank Andrei Jalba for our fruitful collaboration in the last part of my work. On a personal level, I would like to thank my parents and sister for their love and support over the years, my friends for providing distractions outside of the office, and Michelle for her unconditional love and ability to light up my mood when needed.
Synthesis and Electrochemical Performance of Sulfur/Highly Porous Carbon Composites

Sulfur/highly porous carbon (HPC) composites were synthesized by thermally treating a mixture of sublimed sulfur and HPC. The microstructure of the HPC and the composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer−Emmett−Teller (BET) surface area. The specific surface area of HPC reaches up to 1472.9 m2/g, which is sharply reduced to 24.4 m2/g in the sulfur/HPC composite with 57 wt % sulfur. The electrochemical performance of the composites as cathode materials in organic electrolytes was studied by the galvanostatic method and cyclic voltammetry. The sulfur/HPC composite with 57 wt % sulfur delivers the initial high specific capacity up to 1155 mAh/g and a stable capacity of 745 mAh/g after 84 cycles at the current density of 40 mA/g. In addition, it is demonstrated that the excellent cycling stability of the sulfur/HPC composite can be obtained at different current densities. On the basis of the analysis of the mi.