Miracle-dz/UniFAR-FTUs huggingface dataset:
Properties of Arc Cathode Spots

Arc cathode spots operating by formation of surface-microplasmas are reviewed for discharges in vacuum and in gases. New experimental studies using advanced optical methods (image converter cameras and laser absorption techniques) reveal that the spot is composed of fragments with a size below 10 μm. In vacuum these are highly mobile, for copper on a time scale < 50 ns. The motion and the rapid sequences of extinctions and re-ignitions determine the behavior of the whole spot. Cu-spots in vacuum exhibit displacements in times < 100 ns. A tentative explanation of the spot movement is given on the base of the fragment dynamics. In gases the fragments are more separated than in vacuum. The ignition of fragments is discussed in the framework of recent studies on the glow-to-arc transition in high pressure discharges. Finally, new mechanisms for enhanced field electron emission are mentioned.
Fabrication of three-dimensional microstructures using standard ultraviolet and electron-beam lithography

We have designed and fabricated shape-controlled three-dimensional structures combining electron- beam and ultraviolet (UV) lithography. Starting with a tiff file format, a gray scale pattern using a high energy beam sensitive mask is produced with electron-beam direct writing. In only a one step UV exposure, an optical lens and a photonic band gap structure in 16.5 μm thick AZ 4562 positive photoresist, with controlled profile and smooth resist surface, were fabricated. A three-dimensional grid structure was also transferred to a 100 μm thick SU-8 negative photoresist.
Frictional properties of dilute polymer solutions. II. The effect of preaveraging

Our development of the Debye−Bueche theory for the frictional properties of dilute polymer solutions is continued. A simplified version of the mean field theory is introduced that involves a preangular average (PAA) of the hydrodynamic interaction. A comparison is made between the exact mean field theory and the simplified PAA theory for the case of a uniform sphere and of an infinitesimal shell segment distribution.
Fluorescence properties of dissolved organic matter in coastal Mediterranean waters influenced by a municipal sewage effluent (Bay of Marseilles, France)

Environmental context. Marine dissolved organic matter plays a key role in the global carbon cycle. Questions remain, however, as to the influence of anthropogenic activities on its composition and distribution in coastal waters. It was found that dissolved organic matter in the vicinity of a municipal sewage effluent (Marseilles City, France) contained a high proportion of protein-like material, thereby demonstrating the influence of human activities on coastal dissolved organic matter. Abstract. Fluorescent dissolved organic matter (FDOM) in coastal marine waters influenced by the municipal sewage effluent (SE) from Marseilles City (France, north-western Mediterranean Sea) has been characterised. Samples were collectedeleventimesfromSeptember2008toJune2010intheBayofMarseillesalongacoast-openseatransectfromthe SEoutletinthe SouthBayandatthe MediterraneanInstitute Observationsiteinthe centralBay. Fluorescenceexcitation- emission matrices combined with parallel factor analysis (PARAFAC) allowed the identification of two protein-like (tyrosine C1, with excitation maxima (lEx) and an emission maximum (lEm )o f,230, 275/306nm; tryptophan C2, lEx/ lEm,230, 270/346nm)andthreehumic-likecomponents(marinehumic C3,lEx/lEm280/386nm; C4,lEx/lEm235, 340/ 410nm;C5,lEx/lEm255,365/474nm). FromtheSEoutlettothecentralBay,agradientappeared,withdecreasingFDOM intensities, decreasing dissolved organic carbon, particulate carbon, nutrients and faecal bacteria concentrations and increasing salinity values. This gradient was associated with decreasing abundances in protein-like fluorophores and rising abundances in humic-like (C3 and C5) materials. This shift in FDOM composition illustrated the decrease in wastewater inputs and the increase in marine sources of DOM along the transect. FDOM data showed that the Marseilles SE spread up to 1500m off the outlet, but it did not reach the central Bay. Tryptophan-like material was the dominant fluorophoreintheSEanddisplayedthehighestcorrelationswithbiogeochemicalparameters(organiccarbon,phosphates, faecal bacteria). Therefore, it is proposed to use its fluorescence intensity to detect and track SE inputs in the Marseilles coastal marine waters. Additional keywords: Cortiou, EEM fluorescence, PARAFAC, tryptophan.
Waterborne UV-curable polyurethane acrylate/silica nanocomposites for thermochromic coatings

Waterborne UV-curable polyurethane acrylate/silica (PUA/SiO2) nanocomposites were prepared by a sol–gel method. SiO2 nanoparticles were modified by γ-methacryloxypropyltrimethoxysilane (KH-570) and then introduced to the ends of the PUA main chains through radical polymerization. According to the transmission electron microscopy (TEM) results, the size of the PUA/SiO2 nanocomposite particles was approximately 70–100 nm. It was easier to get a uniform emulsion by the sol–gel method than by the physical blending method. Surface tension and contact angle tests both demonstrated the good wettability of the nanocomposites. Besides, the kinetics of the curing process of the PUA/SiO2 films were analyzed by ATR-FTIR and gel content. This revealed that the modified SiO2 could accelerate the curing speed of PUA coatings. Scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA) indicated that the nanosilica were well dispersed in the PUA matrix and the soft and hard segments of PUA/SiO2 were well phase mixed. Furthermore, the nanocomposite films displayed enhanced rigidity, hardness, abrasion resistance and good weather resistance. Finally, waterborne UV-curable PUA/SiO2 nanocomposites were applied to thermochromic coatings, showing excellent temperature sensitivity and reversibility.
Separation of organic pollutants by reverse osmosis and nanofiltration membranes: Mathematical models and experimental verification

Predictive reverse osmosis (RO) models have been well-developed for many systems. However, the applications to dilute organic−water systems require the modification of transport models and the understanding of solute−polymer interactions. Studies with various substituted, nonionized phenolic compounds showed that these could cause substantial membrane water flux drop, even in dilute solutions with negligible osmotic pressure. Further, the organics could significantly adsorb on the cross-linked aromatic polyamide active layer. In some cases, even concentrations as low as 0.2 mM, 2,4-dinitrophenol (solution in particle-free, double-distilled water) can cause as much as a 70% flux drop with an aromatic polyamide membrane. Two models are presented in this paper: a modified steady-state solution diffusion model and an unsteady-state diffusion adsorption model which are able to predict flux and permeate concentrations from a single RO experiment. Further, the development of these models allows for the understa.
Manganese(III) complexes in oxidative decarboxylation of acids

Manganese(II1) effects oxidative decarboxylation of a variety of acids in nonaqueous solutions. The products and stoichiometries of the decarboxylation are examined. The reduction of MnIII follows first-order kinetics. Autoretardation by the MnII formed in the reaction is attributed to mixed valence complexes between MnIII and Mn". Alkyl radicals (and carbon dioxide) formed by multibond homolysis of the MnIII carboxylates are oxidized by a second Mn"1 to alkenes and esters. The enhanced rate of decarboxylation and oxidation of alkyl radicals by MnIII in the presence of strong acids is ascribed to cationic Mn"1 species. Copper(I1) effectively traps alkyl radicals from the decarboxylation. The autoxidative decarboxylation of pivalic acid in the presence of oxygen is catalyzed by Mn"1 and produces high yields of t-butyl alcohol and di-r-butyl peroxide. variety of transition metal compounds have been A employed to catalyze the autoxidation of hydrocarbons. In many cases, these autoxidations involve a rather complex set of reactions and metastable intermediates. In particular, the role of free radicals and their interaction with the metal species are not clear. Manganese(II1) complexes have been used to oxidize a number of types of organic functional groups.2 When manganese compounds are employed in a catalytic capacity, the metal species is thought to alternate between the I1 and I11 oxidation states. MnlI1 in aqueous solutions, however, is especially prone to disproportionate (eq 1). The latter does not 2MnI11 e MnII + MnIV (1) appear t o be as severe a limitation in nonaqueous solutions, since MnlI1 complexes are relatively stable in these media. In this report, we demonstrate the use of M P complexes in the oxidative decarboxylation of acids. Products and kinetic studies are coupled in order to clarify the mechanism of the oxidation, the catalysis by strong acids, the retardation by Mn'I and the inter(1) For a review, see (a) N. M. Emanuel, E. T. Denisov, and Z. K. Maizus, "Liquid Phase Oxidation of Hydrocarbons," Plenum Press, New York, N. Y. , 1967; (b) "Oxidation of Organic Compounds," Advances in Chemistry Series, No. 76, Vol. 2, American Chemical Society, Washington, D. C. , 1968; (c) Angew. Chem. Intern. Ed. Engl. , 8.97 (1969). (2) W. A. Waters and J. S. Littler, "Oxidation in Organic Chemistry," K. B. Wiberg, Ed., Academic Press, New York, N. Y. , 1965, Chapter 3. (3) Except where it is pertinent to the discussion, the ligands associated with the manganese species will not be included. Octahedral coordination generally pertains. mediacy of alkyl radicals. Cu'I to oxidize alkyl radicals are also compared.
Three-capacitor model for surface potential of insoluble monolayers

Three three-capacitor model of Demchak and Fort (Demchak, R. J.; Fort, T., Jr. J. Colloid Interface Sci. 1974, 46, 191) that is widely applied to interpret surface potentials of monolayers at water−air interfaces postulates independent contributions of the hydrocarbon chains, polar head groups, and hydration water. We present an experimental verification of this a priori assumption for condensed monolayers of n-heptadecanol and 16-bromohexadecanol. These substances have different terminal CH3CH2 and BrCH2 groups and exhibit as monolayers ΔV potentials and vertical dipole moments that are opposite in sign. Demchak and Fort's analysis of the head group's conformation leads to controversial conclusions which question the basic assumptions of the three-capacitor model. Three-dimensional maps of the molecular electrostatic potential (MEP) and the molecular lipophilic potential (MLP) show that the ω-dipoles do not influence the electrostatic potential and hydrophilicity of the head groups of single n-heptadecan.
Bis-Hydrophilic Block Terpolymers via RAFT Polymerization: Toward Dynamic Micelles with Tunable Corona Properties

We present the synthesis of well-defined bis-hydrophilic block terpolymers with two outer hydrophilic blocks and an inner hydrophobic block together with studies concerning their colloidal aggregates formed in water. The investigations aim at preparation of dynamic micelles with tunable corona properties. Highly functionalized poly(ethylene oxide) macro-chain-transfer agents (PEO-CTAs) of two molecular weights (2 and 5 kDa) are used as mediating agents in reversible addition fragmentation chain transfer (RAFT) polymerization. The synthesis is accomplished by first polymerizing n-butyl acrylate as a hydrophobic block and then chain extending the diblock copolymers further with various (meth)acrylamide derivatives, acrylamide (AAm), N-isopropylacrylamide (NIPAAm), N,N-diethylacrylamide (DEAAm,) and N-(2-hydroxypropyl)methacrylamide (HPMA). Due to the high degree of functionalization of the PEO-CTA, the blocking efficiency is near quantitative and the diblock copolymers can be obtained easily in a wide range.
Probing the Active Site of Acetylcholinesterase by Molecular Dynamics of Its Phosphonate Ester Adducts

Molecular dynamics (MD) simulations using CHARMM were performed for the solution structures of the pentacoordinate and tetracoordinate PSCS and PRCS adducts of Torpedo californica (Tc) acetylcholinesterase (AChE) formed with 2-(3,3-dimethylbutyl) methylphosphonofluoridate (soman) to assess the molecular origins of stereoselectivity of phosphonylation. MD simulations were also carried out for the PSCS transients in soman-inhibited trypsin to evaluate the differences in the mode of operation of the two enzymes. Parameters for the pentacoordinate phosphonate fragments were constructed from results of an ab initio calculation at the 6-31G* level for a model compound, and those for the tetracoordinate phosphonate fragments were from MNDO calculations. Starting equilibrium structures for the above and for analogous structures for chymotrypsin were generated and energy-optimized in program YETI. The stereoselectivity of AChE for the levorotatory diastereomers of soman amounts to >5.6 kcal/mol difference in trans.
Intermediate-range structure of fast-ion-conducting AgI-doped molybdate and tungstate glasses

The structures of two fast-ion-conducting molecular glasses, and , have been investigated by neutron and x-ray diffraction. Both molybdate and tungstate glasses show a first sharp diffraction peak (FSDP) at very low Q-values ( and respectively) in the neutron data. However, only weak peaks are observed at similar Q-values in the x-ray data. The diffraction results have been used to model the structures using the reverse Monte Carlo (RMC) method. The RMC results show that all partial structure factors contribute to the FSDP except , , and (or ). This implies that the origin of the FSDP is somewhat different from that for the borate and phosphate glasses where and (the corresponding centres of the covalently bonded oxide groups) contribute strongly to the prepeak. The result excludes any simple explanation of the FSDP in terms of AgI clustering.
Simple synthesis and characteristics of Mo/MoS2 inorganic fullerene-like and actinomorphic nanospheres with core–shell structure

High yields of Mo/MoS2 inorganic fullerene-like and actinomorphic nanospheres with a core–shell structure have been successfully synthesized by the one-step reaction of sulfur and molybdenum nanospheres under a hydrogen atmosphere, in which the Mo nanospheres were prepared by the wire electrical explosion method. The shell thickness of MoS2 is about 4–10 nm and exhibit an expansion of about 4.2–1% along the c-axis. Observed from high-resolution transmission electron microscopy images, unreacted molybdenum lying between the (002) layers of MoS2 contributes to the larger expansion besides the strain in the bent layer and the crystal defects; the preferred growth orientations for MoS2 on the surface of Mo have two directions under different annealing temperatures: parallel to the (110) plane of Mo, presenting an actinomorphic phase, and perpendicular or having certain angles to the (110) plane, showing a fullerene-like phase. The actinomorphic Mo/MoS2 can be used for catalysis and intercalation. The fullerene-like phase can be applied as a solid lubricant to enhance the structural rigidity and load bearing capacity of hollow MoS2. In addition, the core–shell nanospheres exhibit a little higher onset temperature and a narrow temperature range against oxidation with a weaker exothermic peak than conventional 2H-MoS2.
Selective Area Growth of InP and Defect Elimination on Si (001) Substrates

We report the selective area growth of InP layers in submicron trenches on Si (001) substrates by using a thin Ge buffer layer. The antiphase domain boundaries in InP layers are suppressed by engineering the local Ge surface profile. The mechanism of atomic step formation and the corresponding method for step density control are presented. We discuss the impact of the surface profile of the Ge buffer layer on the formation of antiphase domain boundaries as well as on InP nucleation. A minimum step density of 0.25 nm ―1 is required to avoid antiphase domain boundaries while a higher step density substantially reduces the stacking faults and twins in the InP nucleation layer. By employing the threading dislocation necking effect and the properly controlled Ge surface profile, high-quality InP layers have been obtained in submicron trenches.
MULTIPLE ACTIVITIES OF ANDROGENIC COMPOUNDS

1. Some multiple effects of male hormones are reviewed. 2. Trans-androstenediol, dehydro-androsterone, androstenedione, and testosterone will cause development of the uterus of the immature rabbit similar to that caused by œstrone. The most active of these, trans-androstenediol, is about 1/2000 as active as œstrone by this test. 3. Trans-androstenediol causes cornification of the vaginal epithelium of the ovariectomised rat; testosterone acetate and propionate have an effect similar to that of the free hormone, in causing mucification. 4. In an orthodox test for œstrogenic activity on a group of 20 ovariectomised mice, trans-androstenediol was found to be about 1/10,000 as active as œstrone. 5. Trans-androstenediol, testosterone, testosterone propionate, and androstanediol will not only prevent the development but also cause the disappearance of the characteristic X-zone in the adrenal cortex of castrated mice, according to the time after castration at which the injections are made. 6. Trans-androstenediol, testosterone, trans-dehydroandrosterone, and androstenedione, but not androstanediol in the dosage used, will feminise the plumage of the Sebright capon. We are much indebted to Dr K. Miescher and Messrs Ciba for their continued assistance in generously supplying the crystalline compounds used in the work described above.
Biodiesel Production with Water-Tolerance and A Microwave Absorbing Catalyst using Tung Oil

The water-tolerant and microwave absorbing solid acid catalyst–-heteropolyacids supported on activated carbon (H3PW12O40•xH2O /C)–-was developed and used in the synthesis of biodiesel with low-quality tung oil that contained water (0.1–1.5 wt.%) or free fatty acid (FFA; 2.6–30.0 wt.%). Microwave radiation was adopted to enhance the transesterification. The response surface methodology (RSM) was used to design the synthesis experiments and optimize the operation conditions. Research results showed that the solid acid catalyst H3PW12O40•xH2O /C (HPW/C) exhibited a better water-tolerance performance and catalytic activity than other catalysts such as HPW and HPW/γ-Al2O3, and a higher yield of fatty acid methyl ester (FAME) could be obtained under microwave radiation than the conventional heating. The FAME yield of 67.2% could be obtained under the optimal conditions of temperature of 343 K, the methanol to oil molar ratio of 36, and catalyst to oil mass ratio of 11.5 wt. % when the tung oil contained 0.7 wt. % water and 2.6 wt. % FFA.
Direct Observation of Wetting and Diffusion in the Hydrophobic Interior of Silica Nanotubes

Fluorescence microscopy techniques are used to investigate diffusion and wetting at the interior surface of template-synthesized silica nanotubes. Imaging of individual nanotubes reveals that complete modification of the nanotube interiors with hydrophobic ligands is attained during nanotube synthesis. Fluorescence recovery after photobleaching experiments show that (1) spontaneous dewetting of the nanotube interior occurs when the immersing solvent is displaced with pure water and (2) anomalously slow diffusion is observed at the nanotube interior surface.
Inferential Conversion and Composition Monitoring via Microcalorimetric Measurements in Emulsion Terpolymerization

Online calorimetry was used to estimate the conversion and the cumulative terpolymer composition in free radical emulsion polymerization of styrene/methyl methacrylate (MMA)/methyl acrylate (MA) within batch and semi-batch stirred tank reactors. The model includes the mass and energy balance equations over the reactor and its peripherals. Energy balance equations include the heat of reaction, internal and external heat transfer effects, as well as external heat losses. Experiments were conducted in conjunction with a reactor instrumented with platinum resistance thermal transducers and gravimetric conversion measurement devices. The experiments were conducted at variable operational conditions of feed rate, temperature and monomer feed ratios. The estimated values of conversion and terpolymer composition obtained from calorimetric data were compared with measurements of conversion and cumulative terpolymer composition by gravimetry and NMR techniques. Good agreement was observed between the inferential calorimetric estimation and corresponding process measurements. We established that online calorimetry is suitable for use as a soft sensor for the prediction of the rate of reaction, conversion and terpolymer composition.
Optimizing the generation of narrow polydispersity ‘arm-first’ star polymers made using RAFT polymerization

In this article, the synthesis of well-defined, narrow polydispersity (PDI < 1.2) star polymersviaRAFT polymerisation is detailed. An ‘arm-first’ method is described using a crosslinked nanogel core. The synthetic conditions and variables were thoroughly investigated and optimised so that nearly quantitative arm incorporation was found to occur. The parameters studied included polymerization time, the arm molecular weight, and the nature of the solvent and cross-linker.
Effects of additives on oxidation characteristics of palm oil-based trimethylolpropane ester in hydraulics applications

Hydraulic fluids represent one of the most important groups of industrial lubricants. Increasing attention to environmental issues drives the lubricant industry to choose vegetable-based hydraulic fluids which are biodegradable as compared to mineral-based fluids. However, the lubricating properties of vegetable oil, such as poor oxidative stability and high pour point, have hindered their use. In this study, trimethylolpropane ester, which was derived from palm-based methyl ester, was used as the base hydraulic fluid. The purpose of the study was to determine the optimum formulation for palm oil-based synthetic lubricants by using suitable additives that can improve the oxidative stability and viscosity in accordance with the standard regulations for hydraulic fluid applications. The oxidative stability of the oil was evaluated by total acid number (TAN) and viscosity tests. In general, base oil without additive began to degrade after 200 h. The formulated oil, on the other hand, was quite stable even after 800 h of operation. The best formulation was obtained using 1.0% of either additive A or additive B. Both TAN and viscosity values were found to increase with increasing heating temperature. Meanwhile, the results have also shown that additive A performs better than additive B. After 800 h of exposure, the final TAN value for the formulated oil was only at 0.32 as compared to 4.88 mg KOH/g for the oil without additive. However, the kinematic viscosity of the oil at 40 and 100 °C was almost unchanged as compared to the oil without additive.
Automated on-Line Dialysis and Column-Switching HPLC Determination of Flumequine and Oxolinic Acid in Fish Liver

Abstract An automated method for residue analysis of oxolinic acid and flumequine in liver of Atlantic salmon is described. Oxolinic acid and flumequine are extracted from liver with 0.4 M phosphate buffer pH 10 and the extracts are automatically analysed by on-line dialysis and column-switching in an HPLC system. The limit of detection was 4 μg/kg for oxolinic acid and 7 μg/kg for flumequine with fluorescence detection. The on-line combination of dialysis and column-switching HPLC was shown to be a reliable technique for residue control of these drugs in fish liver.