Miracle-dz/UniFAR-FTUs huggingface dataset:
Statistical behaviour of internal partial discharges at DC voltage

In this paper the relation between successive partial discharges in insulating materials at DC voltage is discussed. Based on a few assumptions a DC voltage model, based on an RC-circuit, is presented and experimentally verified. Measurements of partial discharges have been made on samples containing air filled voids. For discharges of a small magnitude the model proved to be valid. Based on the model the characteristic discharge parameter mean time lag t, and mean recovery time t, have been obtained. For discharges of larger magnitude, the model is not valid. This is probably due to a different discharge mechanism, the 'streamer like' mechanism. Therefore the model could possibly be used for a recognition of the dominant discharge mechanism. <<ETX>>
Improving charge collection with delafossite photocathodes: a host–guest CuAlO2/CuFeO2 approach

p-Type delafossite CuFeO2 has recently been reported as a promising candidate for direct photoelectrochemical solar water reduction in alkaline conditions. However, despite its favorable optical band gap energy and light absorption, this material suffers from poor electron–hole separation that limits its optimum thickness to a few hundred nanometers. This limitation can be addressed by a host–guest strategy, where a mesoporous p-type scaffold is used to support a thin-film of the light absorber. Here we demonstrate this host–guest approach for the first time with CuFeO2 using p-type transparent CuAlO2 as a scaffold. Optimizing the scaffold layer thickness at 2 μm resulted in a 2.4-fold increase in photocurrent in the presence of O2—a sacrificial electron scavenger—reaching 2.4 mA cm−2 at +0.4 V vs. RHE. Moreover, comparing the performance to host–guest electrodes prepared with an insulating SiO2 scaffold as a control suggested that the observed improvement with CuAlO2 was due to a decreased recombination stemming from improved charge separation in addition to improved charge transport through the scaffold compared to the CuFeO2 film alone.
Density Functional Theory (DFT) with Combined Investigation of the Selectivity of a Symmetrical Tetradentate N2O2-Coordination Schiff Base Ligand for Mn(II) Ion in the Presence of Mixing Mg(II), Mn(II), Ba(II), Ca(II) and Ni(II) Ions

Theoretical study and computational models are capable of reliably predicting ligand selectivity towards variety of metal ions, and can be valuable tools for the advancement of practical works. In this paper, a theoretical study based on the optimum angles and distance between a tetradentate Schiff base ligand and some metal ions is characterized. These investigations are carried out based on ab initio calculations to estimate the pair wise interaction energy between the 2 molecules. The calculations show that the mentioned ligand is a suitable ligand for the extraction of Mn(II) ions from a mixture of Ba(II), Mg(II), Mn(II), Ca(II) and Ni(II) ions. doi: 10.14456/WJST.2014. 6
The mediator head module and regulation of RNA polymerase II transcription initiation.

Acknowledgements " Coming together is a beginning. Keeping together is progress. Working together is success. " This quote describes very well the multidisciplinary and collaborative atmosphere at the Gene Center in Munich. Therefore I am very glad to have decided to do my PhD thesis in the laboratory of Prof. Patrick Cramer. First of all, I would like to thank my supervisor Prof. Patrick Cramer for giving me the opportunity to work in such an inspiring atmosphere and for giving me the freedom to pursue a variety of exciting biological questions and collaborations over the years. His way of running a laboratory and leading people will hopefully influence my future professional and personal life. Thank you, Patrick, for the trust and the personal support during those exciting four years! I am also very thankful to the members of my Thesis Advisory Committee, Prof. Dietmar Martin and Dr. Heidi Feldmann, for their advice, constant support, help with " yeast issues " and numerous discussions. At the same time I want to thank Steve Hahn, an inspiring researcher and certainly one of the nicest persons I have ever met. Thanks Steve, for letting me stay in your lab, for teaching me that a good biochemical experiment needs more controls than actual samples, for writing reference letters and for many great discussions in the lab, in restaurants and at conferences. Next, I want to thank a great scientist, curious investigator, long-standing collaborator and very dear friend. " Merci beaucoup " Laurent, for sharing projects, first-authorships, ideas, lunch/coffee breaks, homemade " Foie gras with Périgord truffle " and loads of chocolate with me. You taught me many critical methods including protein purification, crystallization, data processing and preparing the world's most delicious brownie. At the same time, I want to thank you, Larissa, for being a great colleague and very good friend over the past years. Without you taking over a huge amount of the experimental workload and keeping me company during all those lunch/coffee breaks, many projects would not have been successful. I am also very thankful to Rike, Erika and Sonja, my present and former " bench neighbors " and good friends, for proofreading as well as sharing ideas, projects, jokes, lunch/coffee breaks, buffers, protocols, hiking trips… ACKNOWLEDGEMENTS III Having many collaborations of course means many more people to thank: Fabian and Toni, both outstanding students, for their dedication to the projects and …
Evaluation of Ethanol, 1‐Propanol, and 2‐Propanol in a Direct Oxidation Polymer‐Electrolyte Fuel Cell A Real‐Time Mass Spectrometry Study

Ethanol, 1-propanol, and 2-propanol have been evaluated as alternative fuels for direct methanol/oxygen fuel cells. The relative product distributions for the electro-oxidation of these alcohols under fuel-cell conditions were determined using on-line mass spectrometry. For water/ethanol mole ratios between 5 and 2, ethanol is the main product, while CO{sub 2} is a minor product. However, an increase of the water/ethanol mole ratio increased the relative product distribution of CO{sub 2} slightly. Propanol was the main product of the electro-oxidation of 1-propanol with a similar percentage of CO{sub 2} being formed as for ethanol. In contrast, the electro-oxidation of 2-propanol yielded practically only acetone. Between 150 and 190 C, the product distributions for the electro-oxidation of ethanol, 1-propanol, and 2-propanol do not depend significantly on the temperature. No differences in the product selectivities of Pt-Ru and Pt-black were found. Ethanol is a promising alternative fuel for direct methanol fuel cells (DMFCs) with an electrochemical activity comparable to that of methanol. Conversely, 1-propanol and 2-propanol are not suitable as fuels for DMFCs due to their low electrochemical activity.
Development and Validation of UV Spectrophotometric Method of Nimodipine in Bulk and Tablet Formulation

A simple, sensitive and precise UV spectrophotometric method was developed for the estimation of Nimodipine in tablet dosage form. The optimum conditions for the analysis of the drug were established. The wavelength maxima (λmax) for Nimodipine was found to be 238.5 nm. Beer’s law was obeyed in the concentration range of 5? 30 mcg/mL having line equation y = 0.033x + 0.020 with correlation coefficient of 0.9981. The slope, intercept, correlation coefficient, detection and quantization limits were also calculated. Results of the analysis were validated statistically and by recovery study. The proposed method can be applied for the routine analysis of Nimodipine from tablet formulation.
An Introduction to Electrical Breakdown in Dielectrics

Abstract : This report was written to serve as a text for an introductory graduate course in high voltage engineering at the Air Force Institute of Technology. However, anyone with and undergraduate electrical engineering or physics degree should be able to understand it, if they so desire. The material presented falls into three sections. The first part discusses the basics of kinetic theory of gases, atomic structure, ionization, mobility, diffusion, and electron emission. The second portion covers gas breakdown and the characteristics of the glow, corona, and arc discharges. the final portion provides a very brief introduction to the literature are provided.
Broensted superacidity of hydrochloric acid in a liquid chloroaluminate. Aluminum chloride - 1-ethyl-3-methyl-1H-imidazolium chloride (55.O m/o AlCl3)

The system HCl (0.1-1 atm)/AlCl{sub 3}-EMIC (55.0 mol % AlCl{sub 3}) (EMIC = 1-ethyl-3-methyl-1H-imidazolium chloride) at 23{degree}C is a Broensted superacid capable of protonating arenes to a degree similar to that of liquid HF at 0{degree}C (H{sub 0} = {minus}15.1). Arenes used in this investigation were biphenyl (I), naphthalene (II), 9H-fluorene (III), chrysene (IV), 2-methylnaphthalene (V), mesitylene (VI), pentamethylbenzene (VII), hexamethylbenzene (VIII), anthracene (IX), and 9,10-dimethylanthracene (X). In both the chloroaluminate melt and HF I is a weak base while VIII-X are strong bases. In between these extremes the order of basicities in both media is II < III and IV < V < VI < VII < VIII. A study of the effect of HCl partial pressure showed, for example that V is 50% protonated at 0.3 atm HCl. The overall reaction is arene + HCl + Al{sub 2}Cl{sub 7}{sup {minus}} {r reversible} arene {times} H{sup +} + 2AlCl{sub 4}{sup {minus}} and is reversible. The degree of protonation was measured by optical absorption spectrophotometry. The arenes are stable in the liquid chloroaluminate for many hours, and their protonated forms (arenium ions) are stable for 1 h or more. A new procedure for the preparation of EMIC was developed thatmore » yields exceptionally clean AlCl{sub 3}-EMIC melts with very low concentrations of protic and oxidizing impurities. 17 refs., 6 figs., 2 tabs. « less
CS109B Advanced Section : Information Theory, Variational Inference for Variational AutoEncoders and Bayesian Neural Networks

In this tutorial, we discuss a brief introduction to information theory that presents salient concepts such as entropy, cross entopry and KL divergence. Using these fundamentals, the tutorial then introduces variational inference formulation along with mean ﬁeld approximations. Then, variational autoencoders - both the generative and conditional variants are introduced to demonstrate a salient application of amortized variational inference with a neural net parametrization. Finally, Bayesian Neural Networks are introduced and the tutorial concludes with a backpropagation friendly variational inference algorithm to perform probabilistic reasoning on feedforward neural networks
pH-responsive poly(N,N-dimethylaminoethyl methacrylate-co-2-acrylamido-2-methyl-propanosulfonic acid) cryogels: swelling, elasticity and diffusive properties

A series of ionic poly(N,N-dimethylaminoethyl methacrylate-co-2-acrylamido-2-methyl-propanosulfonic acid) (P(DMAEMA-co-AMPS)) cryogels were prepared by free-radical crosslinking copolymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA) and 2-acrylamido-2-methyl-propanosulfonic acid (AMPS) in aqueous solution. The swelling properties and the elastic behavior of P(DMAEMA-co-AMPS) cryogels drastically change at a gel preparation temperature, −18 °C, below the bulk freezing temperature of the polymerization solvent, water. The equilibrium and dynamic swelling/deswelling properties of the prepared cryogels responding to pH as well as in aqueous solutions of NaCl, KCl, MgC12, Na2S04, K2S04, and MgS04 were investigated. The influence of the relative content of ionic comonomer AMPS on the swelling properties was examined in water and the obtained results were compared with P(DMAEMA-co-AMPS) hydrogels synthesized at usual polymerization temperature. The ionic gels prepared with higher DMAEMA contents exhibited a highly pH-dependent equilibrium swelling behavior. The extent of transition from the swollen state to the shrunken state was strongly related to the DMAEMA content of the network. The results indicated that P(DMAEMA-co-AMPS) cryogels not only had considerable swelling ratio as well as rapid swelling/deswelling kinetics, but also exhibited improved mechanical properties.
Modulation of Liver Inflammation and Fibrosis by Interleukin-37

Background and Aims: Chronic inflammation induces liver fibrosis, cirrhosis and potentially liver cancer. Kupffer cells modulate hepatic stellate cells by secreting immunologically active proteins as TGF-β. TGF-β promotes liver fibrosis via the activation of Sma- and Mad-related protein 3. IL-37 broadly suppresses innate and adaptive immune responses. Intracellular IL-37 interacts with Smad3. We hypothesize that IL-37 downregulates the activation of hepatic Kupffer and stellate cells and interferes with the TGF-β signaling cascade to modulate liver fibrogenesis. Methods: The role of IL-37 on liver inflammation and fibrogenesis was assessed in three mouse models as well as isolated Kupffer- and stellate cells. Serum IL-37 was tested by ELISA in a clinical cohort and correlated with liver disease severity. Results: Transgene expression of IL-37 in mice extends survival, reduces hepatic damage, expression of early markers of fibrosis and histologically assessed liver fibrosis after bile duct ligation. IL-37tg mice were protected against CCl4-induced liver inflammation. Colitis-associated liver inflammation and fibrosis was less severe in IL-10 knockout IL-37tg mice. Spontaneous and LPS/TGF-β-induced cytokine release and profibrogenic gene expression was lower in HSC and KC isolated from IL-37tg mice and IL-37 overexpressing, IL-1β stimulated human LX-2 stellate cells. However, administration of recombinant human IL-37 did not modulate fibrosis pathways after BDL in mice, LX2 cells or murine HSCs. In a large clinical cohort, we observed a positive correlation of serum IL-37 levels with disease severity in liver cirrhosis. Conclusions: Predominantly intracellular IL-37 downregulates liver inflammation and fibrosis. The correlation of serum IL-37 with disease severity in cirrhosis suggests its potential as a novel target modulating the course of liver fibrosis.
Magnetism of Cr Impurities Embedded in Cu fcc Matrix: Density Functional Calculations

We present extensive first principles density functional theory (DFT) calculations dedicated to analyze the magnetic properties of Crn (n = 2 and 3) impurities embedded in a Cu fcc matrix. We consider several dimers and trimers having different interatomic distances. In all cases the Cr atoms have been embedded as substitutional impurities in the metallic network. For the case of the dimers we have considered two magnetic configurations: Ferromagnetic (Antiferromagnetic) when the atomic magnetic moments are parallel (antiparallel) each other, for this case we have found that the lowest-energy state corresponds to the antiferromagnetic coupling between Cr atoms whose interatomic distance is a√2. In the case of the Cr trimers we have considered three or four magnetic configurations, depending on the Cr impurity geometry, for this case we have found that the lowest-energy state corresponds to the antiferromagnetic Cr trimer AF (↑,↓,↓) forming an isosceles right angle triangle whose hypotenuse and legs length are a√2 and a, respectively, with magnetic moments c (2) = 3.45/-3.32/3.45 μB.
Pretreatment and kinetics of oil extraction from algae for biodiesel production

In this study, extraction of lipid from algal sp. Chlorella vulgaris is investigated based on Bligh and Dyer method employing methanol and chloroform on wet biomass. Optimization methodology was established on comparison of pretreatment methods as well as investigation of ultrasonication and stirrer parameters to enhance cell disruption. It was found that biomass with water/solid proportion (w/s = 5) operating temperature of 50 °C both for ultrasonication and shaking, 5 min ultrasonication with further 3 h of stirring with 200 rpm is the best set of parameters for breakdown of cell envelops, and using these parameters, total extraction of 22.07% was obtained. Kinetic study of breakdown was carried out with further full-factorial investigation of extraction (%) vs time and temperature. Using Arrhenius equation, activation energy of about 34.73 kJ/mol was obtained for this algal sp. with R2 = 97.81%. Further analysis using analysis of variance showed that when using lower temperatures, sudden increase of extraction occurs in longer times, and vice versa, hence emphasizing the interaction thereof. It was also found that temperature plays the vital role among all examined parameters. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.
Controlled Growth of Zinc Oxide Nanorods by Aqueous-Solution Method

The controlled growth of zinc oxide nanorods in aqueous-solution is reported. Zinc oxide (ZnO) micro- and nano-rods were successfully prepared on gold-seeded Si substrates in aqueous solution containing 1:1 ratio of varying concentrations of zinc nitrate hexahydrate (Zn(NO3)2.6H2O) and hexamethylenetetramine (HMTA) (C6H12N4). The ZnO rods were characterized by scanning electron microscopy, X-ray diffraction and photoluminescence (PL) spectroscopy. A unique evolution of size and growth orientation is directly affected by the change in concentration of Zn2 + solution. The mechanism of growth governed by HMTA and chemical equations are suggested.
DETERMINATION OF FOOD SYNTHETIC DYES IN POWDERS FOR JELLY DESSERTS USING SLIT-SCANNING DENSITOMETRY AND IMAGE ANALYSIS METHODS

A high-performance thin-layer chromatographic method combined with a sample preparation procedure has been developed for simultaneous determination of sunset yellow and azorubine synthetic dyes in powders for jelly desserts containing a variety of other ingredients. Some different extraction solvents and sample preparation steps (solid phase extraction procedures on RP-18 and polyamide cartridges) were tested for the quantitative isolation and purification of dyes. The best recovery results were achieved by using methanol for extraction procedure followed by solid phase extraction on the polyamide cartridges for the purification step. For the quantitative evaluation of the chromatographic spots, visible slit-scanning densitometry and digital processing of images of chromatographic plates (using ImageDecipher-TLC software with pure color-green and blue and integrate color- grey channels selection) were compared. The best statistical parameters for the linear functions of the calibration were obtained using ImageDecipher-TLC software for the quantitative evaluation of the investigated dyes. The lowest limits of detection and quantification (0.0096 and respectively 0.0190 µg/spot for azorubine and 0.0117 and respectively 0.0231 µg/spot for sunset yellow) were obtained by selecting pure color (green and blue) channels for dyes determination. The results obtained for commercial food samples showed that the proposed method is suitable for rapid routine analysis of synthetic dyes in powders for jelly dessert samples.
High resolution Fourier transform spectroscopy of jet-cooled molecules

The spectroscopic literature reporting on the coupling between Fourier transform spectrometers and supersonic jet expansions is reviewed. Particular attention is devoted to high resolution infrared absorption experiments. Short and much longer introductions are provided on Fourier transform spectrometers and jets, respectively, with emphasis on the problems raised by coupling the two techniques. Details of the optical designs reported in the literature are considered. The literature on all the molecules studied is tabulated. Some of the spectroscopic results are highlighted, in particular those obtained at Universite Libre de Bruxelles.
Empirical evaluation of the relationship between soil dielectric constant and volumetric water conte

SUMMARY The paper is addressed to soil scientists who use Time-Domain Reflectometry (TDR) technology to measure soil moisture. The practical aspects of the measurement calibration are discussed, and an empirical approach to establishing the existence of a universal calibration function is presented. Samples of 11 mineral soil horizons and seven organic soil horizons with different chemical and physical properties (including magnetic properties) were selected with the aim of determining their dielectric constant-volumetric water content relationship as calibration functions for TDR soil moisture measurements. These samples were supplemented by other, soil-like, capillary-porous reference materials (montmorillonite, glass beads, washed sand and a sand from a C horizon). The study showed that a unique calibration function for mineral soils and another distinct calibration function for organic soils can be established.
Electrospun hollow glassy carbon–reduced graphene oxide nanofibers with encapsulated ZnO nanoparticles: a free standing anode for Li-ion batteries

Although zinc oxide (ZnO) has a high theoretical capacity for lithium (Li) storage, it has poor cyclability because of the huge volume changes during charge–discharge cycles resulting in particle pulverization and detachment from the current collector. In this paper, a novel anode architecture for Li-ion batteries fabricated by encapsulation of ZnO nanoparticles in the hollow core of glassy carbon–reduced graphene oxide (C–rGO) electrospun composite nanofibers, is described. A one-step, co-axial electrospinning method is used to synthesize a mat of core–shell structured composite nanofibers composed of rGO embedded in poly(acrylonitrile) (shell) and a ZnO nanoparticle precursor with a carrier polymer (core). Subsequent calcination and carbonization produce a mechanically stable anode material, which is used directly as a free-standing anode (∼60 μm thick) without any binder and current collector, which are inactive materials that only add to the battery mass and volume. The ZnO–C–rGO nanofiber composite was characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and X-ray diffraction. The electrochemical performance of the composite was studied by galvanostatic charge–discharge measurements at different current densities, slow scan cyclic voltammetry (CV) and impedance measurements. Incorporation of an rGO network in the glassy nanofiber shell enhances both the capacity and electrical conductivity of the mat electrode resulting in faster electron kinetics, and thus, an improved rate capability. The interior void spaces combined with the mechanical strength and flexibility of the C–rGO shell act as a structural buffer effectively relieving the volumetric stresses generated during charge–discharge cycles. The synergistic effect of the metal oxide, rGO and the core–shell design results in a high capacity of 815 mA h g−1 at a current density of 50 mA g−1 with capacity retention of almost 80% after 100 cycles, thus demonstrating significant potential as an anode substitute for next generation Li-ion batteries.