Miracle-dz/UniFAR-FTUs huggingface dataset:
Silver nanoparticles supported on silica-coated ferrite as magnetic and reusable catalysts for oxidant-free alcohol dehydrogenation

Silver (0) nanoparticles supported on silica-coated ferrite were synthesized to be used as an efficient and recyclable heterogeneous catalyst for oxidant-free dehydrogenation of alcohols to the corresponding carbonyl compounds. The catalyst can be easily recovered and reused for 8 reaction cycles without considerable loss of activity. The facile recovery of the catalyst is carried out by applying an external magnetic device. The catalyst was fully characterized by the techniques of TEM, SEM, XRD, EDS, ICP-AES, and VSM.
Synthesis of polypyrrole nanofibers by ultrasonic waves

Nanofibers of polypyrrole have been synthesized by sonochemical method in the presence of a structure directing agent, i.e. dodecyl benzene sulphonic acid (DBSA). The length of the fibers is seen to increase significantly from ∼13 nm to greater than ∼1700 nm, while the diameter is ∼13–17 nm, respectively. The reaction was carried out under ambient conditions by varying the concentration of pyrrole (0.001–0.1M), ammonium persulphate (0.0075–0.02M), and DBSA (0.05–0.2M). However, the formation of fibers is observed at a specific ratio of 1 : 0.5 : 5. The UV–vis spectra exhibit a sharp peak at a wavelength of ∼490 nm corresponding to the polaron band indicating the formation of polypyrrole. The X-ray diffractogram shows a broad peak in the 2θ range of ∼10°–30° and two sharp peaks at ∼31° and 32° confirming the formation of polypyrrole. The morphological analysis of the sample have been carried out by transmission as well as scanning electron microscopy which reveals the formation of extraordinary long fibers having the length extending to more than ∼1700 nm. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Amperometric Glucose Biosensors Based on Integration of Glucose Oxidase onto Prussian Blue/Carbon Nanotubes Nanocomposite Electrodes

Nanosized Prussian blue (PB) particles were synthesized with a chemical reduction method and then the PB nanoparticles were assembled on the surface of multiwall carbon nanotubes modified glassy carbon electrode (PB/MWNTs/GCE). The results showed that the PB/MWNTs nanocomposite exhibits a remarkably improved catalytic activity towards the reduction of hydrogen peroxide. Glucose oxidase (GOD) was immobilized on the PB/MWNTs platform by an electrochemically polymerized o-phenylenediamine (OPD) film to construct an amperometric glucose biosensor. The biosensor exhibited a wide linear response up to 8 mM with a low detection limit of 12.7 μM (S/N=3). The Michaelis–Menten constant Km and the maximum current imax of the biosensor were 18.0 mM and 4.68 μA, respectively. The selectivity and stability of the biosensor were also investigated.
Coordination modes of 3-hydroxypicolinic acid: synthesis and crystal structures of palladium(II), platinum(II) and rhenium(V) complexes

The new palladium and platinum complexes with 3-hydroxypicolinic acid (HpicOH) [M(PPh3)2Cl(picOH)]·CHCl3, [M(bipy)(picOH)]Cl [M=Pd(II) or Pt(II)], K[PdCl(picOH)2] and [Pt(picOH)2] and the new rhenium complexes [ReOI2(PPh3)(picOH)] and [ReO(PPh3)(picOH)2]I have been prepared. The crystal structures of [M(PPh3)2Cl(picOH)]·CHCl3 [M=Pd(II) 1 or Pt(II) 2] and [ReOI2(PPh3)(picOH)] 3 were determined by X-ray diffraction. Complex 3 exhibits a distorted octahedral geometry with the picOH− ligand showing N,O-chelation with a small bite angle O–Re–N of 74.8(3)°. In complexes 1 and 2 the metal centre is surrounded by a NP2Cl donor set in a distorted square planar arrangement. Therefore, the picOH− ligand is bound through the nitrogen atom, but the distances found between the metal and the carboxylate oxygen [Pd···O(71) 2.773(5) A or Pt···O(71) 2.734(4) A] suggest a [4+1] coordination consistent with N,O-chelation for palladium and platinum centres. Infrared, Raman, 1H and 13C-{1H} NMR spectroscopic data for the complexes are consistent with the crystallographic results. In the solid state the complex units of 1 and 3 are aggregated in centrosymmetric dimers based on C–H···Cl or C–H···O hydrogen bonding interactions between the chlorine of the Pd–Cl bond (in 1) or the phenolic oxygen of the picOH− anion (in 3) and a hydrogen atom of a phenyl group of a PPh3 ligand.
Thermodynamical study of poly(n‐hexyl methacrylate) with some solvents by inverse gas chromatography

The retention volume diagrams of ethyl acetate, isobutyl acetate, tert-butyl acetate, benzene, n-hexane, n-heptane, n-octane, acetone, chloroform, and acetonitrile on the poly(n-hexyl methacrylate) (PHMA) were plotted at temperature ranges from 333 to 393 K by inverse gas chromatography technique. Some polymer-solvent thermodynamic interaction parameters, such as weight fraction activity coefficient, Ω, Flory-Huggins, χ, hard-core, χ, and some exchange parameters such as effective energy, Xeff, enthalpy, X12, and entropy, Q12, were determined for studied solvents at infinite dilution of PHMA at temperatures mentioned above. Then the partial molar heat, , and free energy, , of sorption as well as the partial molar heat, , and free energy, , of mixing at infinite dilution were determined. In addition, the solubility parameter of PHMA, δ2, was determined as 8.8 (cal/cm3)1/2 at room temperature by extrapolation of the values of solubility parameters from studied temperatures to 298 K. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Statistical Mechanics of Defect‐Containing Solids. I. General Formalism

A formalism is set up for treating the contributions of point defects to the thermodynamic functions of crystalline solids by means of a cluster expansion of the partition function. Similar expansions for the defect distribution functions and potentials of average force are derived. The assumptions involved and the necessary differences between the formalism and the McMillan—Mayer theory of solutions are discussed. Problems arising in the explicit evaluation of the coefficients of the virial expansions are discussed and possible applications of the formalism suggested.
Cu(In,Ga)Se2 thin-film solar cells based on a simple sputtered alloy precursor and a low-cost selenization step

High-efficiency thin-film solar cells based on Cu(In,Ga)Se2 are often formed by depositing precursor films and using a subsequent selenization step. We demonstrate a simple and cost-efficient approach simplifying both process steps by using a ternary Cu-In-Ga alloy targetforsputterdepositionoftheprecursorlayerandbyusingasimplenonvacuum selenization reactionbasedonelementalselenium.Inthiscontributionweexamineindetailthecharacteristics of the precursor layers. The sputter growth is governed by a segregation of In-rich islands on top of a closed Cu-rich base. With optimized layers we could achieve conversion efficiencies well above 13% without the use of antireflective coating or metallic grids. The influence of the selenization duration on morphology and performance is discussed. C 2011 Society of Photo-Optical
Functional galactomannan platform from convenient esterification in imidazolium-based ionic liquids

Various imidazolium-based ionic liquids (ILs), considered as “green” solvents, were used as efficient solvents for galactomannan and more specifically for guar gums of high molecular weight. FT-IR as well as the high activation energies reflect hydrogen bonds between the guar backbone and anions of ILs which act as chaotropic agents. Importantly, the dissolution was conducted under mild conditions which allowed the preservation of the chain integrity, as proved by SEC, FT-IR and ATG analyses collected for guar regenerated from IL solutions. For the first time, ILs were exploited as reactional media in which tailor-made guar derivatives were synthesized through a direct and homogeneous esterification with a variety of acid chlorides. We demonstrated that the degree of substitution of guar can be varied by experimental conditions and that it is necessary to adjust these conditions as a function of the esterifying reagent structure. The use of hexanoyl chloride imparted emulsifying properties to guar and esterification with acryloyl chloride and 2-chloropropionyl chloride allowed generation of reactive precursors such as macromonomer and macroinitiator, respectively. The reactivity of the guar macromonomer was assessed through a thermal cross-linking radical copolymerisation, which led to guar gel with solid-like behaviour.
Data-Driven Prediction and Optimization of Energy Use for Transit Fleets of Electric and ICE Vehicles

Due to the high upfront cost of electric vehicles, many public transit agencies can afford only mixed fleets of internal combustion and electric vehicles. Optimizing the operation of such mixed fleets is challenging because it requires accurate trip-level predictions of electricity and fuel use as well as efficient algorithms for assigning vehicles to transit routes. We present a novel framework for the data-driven prediction of trip-level energy use for mixed-vehicle transit fleets and for the optimization of vehicle assignments, which we evaluate using data collected from the bus fleet of CARTA, the public transit agency of Chattanooga, TN. We first introduce a data collection, storage, and processing framework for system-level and high-frequency vehicle-level transit data, including domain-specific data cleansing methods. We train and evaluate machine learning models for energy prediction, demonstrating that deep neural networks attain the highest accuracy. Based on these predictions, we formulate the problem of minimizing energy use through assigning vehicles to fixed-route transit trips. We propose an optimal integer program as well as efficient heuristic and meta-heuristic algorithms, demonstrating the scalability and performance of these algorithms numerically using the transit network of CARTA.
Silica Sulfuric Acid: An Efficient, Reusable, Heterogeneous Catalyst for the One-Pot, Five-Component Synthesis of Highly Functionalized Piperidine Derivatives

Abstract A series of highly functionalized piperidine derivatives was synthesized through one-pot, five-component reaction of aldehydes, amines, and β-ketoesters. Silica sulfuric acid efficiently catalyzes the reaction to afford the corresponding piperidine derivatives in good yields. As a representative example, heating of 4-methylaninle, 4-fluorobezaldehyde, and methyl-acetoacetate in methanol in the presence of silica sulfuric acid furnished the corresponding ethyl 2,6-bis(4-fluorophenyl)-1-p-tolyl-4-(p-tolylamino)-1,2,5,6-tetrahydropyridine-3-carboxylate in excellent yield (85%). Most of the synthesized compounds were screened in vitro for their antibacterial and antifungal activities. Most of compounds showed significant antibacterial activity. GRAPHICAL ABSTRACT
Morphology and Conformation Analysis of Self‐Assembled Triblock Copolymer Melts

We used the dissipative particle dynamics method to simulate the self-assembly of symmetric triblock copolymers of the type ABA. Depending on the volume fraction of the end blocks f A , several mesophases including lamellar, perforated lamellar, gyroid, hexagonal cylinders and bcc spherical micelles were obtained. The order-disorder transition (ODT) at f A = 0.5 was found to be about ΧN = 19.8. The ODT for the cylindrical mesophase at symmetrical points on the phase diagram had different values, indicating asymmetry in the phase diagram. We were also able to estimate the bridge fraction in the different mesophases. They range from about 0.44 for the lamellar mesophase to about 0.75 for the spherical micelles. Our simulation results are in good agreement with previously reported theoretical calculations and experimental observations.
Ab initio modeling of fluorescence fluctuation spectroscopy

Fluorescence correlation spectroscopy (FCS) has developed into a widely used and very successful spectroscopic technique for detecting and quantifying minute concentrations of fluorescing dyes in solution, as well as for obtaining information about molecular parameters such as diffusion coefficients, photophysical transition rates, or chemical reaction kinetics. The standard evaluation method of FCS data is based on the simplified assumption that the convolution of the excitation intensity distribution and the light collection efficiency function is a three-dimensional Gaussian distribution. Although that assumption leads to satisfactory fits of experimental data, the adjustable parameters of this standard model have a rather unphysical meaning. In the present paper, an ab initio approach to modeling FCS curves is developed that is based on exact wave-optical calculations of fluorescence excitation and detection. Comparison with the standard model is made, and the ab initio calculated model curves are used for fitting experimental data and deriving absolute values of diffusion coefficient and concentration.
Determination of Quinine, Quinidine, and Cinquinidine by Capillary Electrophoresis

This article presents the results of the research on a newly developed methodology for the separation and determination of quinine and its two derivatives. The analyzed compounds are biologically active, which are used in the treatment of malaria. The mixture of the analyzed compounds, i.e., hydrochlorides: quinidine, quinine, and cinquinidine, was dissolved in water and then exposed to optimization of separation and determination by isotachophoresis. The analysis was conducted with a varying number of steps and varying time of analysis, different intensities and voltages of the electric current, and different high voltage limits. For the ternary mixture, the optimal time of analysis was just over 8 min. On the other hand, the determination of cinquinidine had the shortest time of analysis (less than 3 min). The conducted validation of the developed methodology indicates very good conditions for the determination of quinidine, quinine, and cinquinidine.
Aqueous RAFT Synthesis of Micelle-Forming Amphiphilic Block Copolymers Containing N-Acryloylvaline. Dual Mode, Temperature/pH Responsiveness, and “Locking” of Micelle Structure through Interpolyelectrolyte Complexation†

Temperature- and pH-responsive, micelle-forming, amphiphilic block copolymers were prepared from N,N-dimethylacrylamide (DMA), N-isopropylacrylamide (NIPAM), and N-acryloylvaline (AVAL) utilizing aqueous reversible addition−fragmentation chain transfer (RAFT) polymerization. A series of block copolymers were synthesized by employing DMA as a macro-chain transfer agent to mediate the statistical copolymerization of NIPAM with AVAL. Structural organization and solution behavior were investigated utilizing dynamic light scattering, two-dimensional NMR spectroscopy, and transmission electron microscopy. It has been demonstrated that the critical micellization temperature for the block polymers can be tuned to range from ≈10 to 36 °C by adjusting the solution pH. Micelles with apparent hydrodynamic diameters from 45 to 86 nm are formed between pH 2 and 5. Above pH 5, a sufficient number of the AVAL units are deprotonated which prevents micellization. The extent of pH and temperature changes on the apparent hyd.
Influence of Additives on the Width of the Metastable Zone

The width of metastable zone of unseeded potassium alum solutions was determined for different conditions and in the presence of additives. The measurements were taken at three different cooling rates and for three different saturation temperatures at a cooling rate of 10 K/h by means of an ultrasonic measuring technique. The influence of Cr3+, Cu2+, and Mg2+ ions on the width of metastable zone of a potassium alum solution was investigated at a cooling rate of 5 K/h. The influence of Mg2+ ions on the width of metastable zone of potassium chloride solutions was also investigated at a cooling rate of 10 K/h. Cr3+, Cu2+, and Mg2+ ions show both enlargement and suppression effects on the width of metastable zone of potassium alum and potassium chloride solutions depending on their concentrations. Cr3+, Cu2+, and Mg2+ ions also change the saturation temperature of potassium alum solutions depending on their concentrations.
Seed Yield and Quality of Winter Oilseed Rape as Affected by Nitrogen Rates, Sowing Time, and Fungicide Application

Abstract This work reports the results of studies on the impact of sowing times (three dates), application of fungicides (protected and unprotected plots), and nitrogen rates (five treatments) on the seed yield, contents of crude protein (CP), glucosinolates (GSL), and crude fat (CF) in seed and on major unsaturated acids (oleic C18:1, linoleic C18:2, and linolenic C18:3) in oil of winter rape (Brassica napus L.) cv. Kasimir. A split–split plot design was used in the field trial conducted on Endocalcari–Epihypogleyic Cambisol during 1998–2002. Seed samples were analyzed by near infrared spectroscopy. ANOVA analysis was used to assess the significance of each factor for the yield and quality of seed of the tested cultivar. The seed yield significantly depended on harvest year, N rates annually, sowing time in three experimental years, and fungicide application in two years. CF and CP concentrations were significantly affected by sowing time and N rates each year of the experiment. A significant effect of fungicides was identified only in one harvest year. GSL concentration was significantly affected by sowing time in three years, by fungicides in two years, and by nitrogen rate annually. The effect of the studied factors on the composition of major unsaturated acids was inconsistent. Sowing time significantly affected the content of all three unsaturated acids in two years and fungicides only in one of the four harvest years.
In-Memory Computing Using Formal Methods and Paths-Based Logic

The continued scaling of the CMOS device has been largely responsible for the increase in computational power and consequent technological progress over the last few decades. However, the end of Dennard scaling has interrupted this era of sustained exponential growth in computing performance. Indeed, we are quickly reaching an impasse in the form of limitations in the lithographic processes used to fabricate CMOS processes and, even more dire, we are beginning to face fundamental physical phenomena, such as quantum tunneling, that are pervasive at the nanometer scale. Such phenomena manifests itself in prohibitively high leakage currents and process variations, leading to inaccurate computations. As a result, there has been a surge of interest in computing architectures that can replace the traditional CMOS transistor-based methods. This thesis is a thorough investigation of how computations can be performed on one such architecture, called a crossbar. The methods proposed in this document apply to any crossbar consisting of two-terminal connective devices. First, we demonstrate how paths of electric current between two wires can be used as design primitives in a crossbar. We then leverage principles from the field of formal methods, in particular the area of bounded model checking, to automate the synthesis of crossbar designs for computing arithmetic operations. We demonstrate that our approach yields circuits that are state-of-the-art in terms of the number of operations required to perform a computation. Finally, we look at the benefits of using a 3D crossbar for computation; that is, a crossbar consisting of multiple layers of interconnects. A novel 3D crossbar computing paradigm is proposed for solving the Boolean matrix multiplication and transitive closure problems and we show how this paradigm can be utilized, with small modifications, in the XPoint crossbar memory architecture that was recently announced by Intel.
A direct ab-initio trajectory study on the ionization dynamics of the water dimer

Ionization processes of a water dimer have been investigated by means of full dimensional direct ab-initio trajectory method. The structure of (H 2 O) 2 before the ionization was simulated at 10 K up to 2 ps by means of a direct ab-initio molecular dynamics (MD) method. Sixty geometrical configurations were selected from the MD calculation, and then the dynamics of (H 2 O) 2 + were calculated by means of a direct ab-initio trajectory method under a constant energy condition. The trajectories on two electronic state potential energy surfaces of (H 2 O) 2 + , i.e., the 2 A" and 2 A' states, were full-dimensionally calculated under the C, symmetry. For the 2 A" state, a complex composed of H 3 D + and OH, which is expressed by (H 3 O + )OH, was only formed as a long-lived complex. On the other hand, in the ionization to the 2 A' state, two reaction channels, the complex formation (H 3 D + )OH ( 2 A') and direct dissociation (H 3 D + + OH) were open as product channels. The dynamics calculations indicated that the proton of H 2 O + transferred to H 2 O within 100-150 fs for the 2 A" state, whereas the proton transfer at the 2 A' state occurs faster (30-50 fs) than that of the 2 A" state. The mechanism of the ionization dynamics of (H 2 O) 2 was discussed on the basis of theoretical results.
The reaction talc + forsterite = enstatite + H2O revisited: Application of conventional and novel experimental techniques and derivation of revised thermodynamic properties

Abstract The reaction 2 talc + 2 forsterite = 5 enstatite + 2 H2O has been investigated between 1 and 3.5 GPa. Here, we report the results from 2 sets of experiments: (1) “conventional”. static quenching experiments performed several years ago in non-end-loaded and end-loaded piston-cylinder apparatus, and (2) a new set of experiments conducted in a novel type of apparatus, a “rocking” piston cylinder. This new technique was employed for the reinvestigation to overcome segregation problems encountered during static experiments. The run-products of the latter experiments are homogenous throughout the entire capsule. The reaction was bracketed to 680.690 °C at 1 GPa, to 660.680 °C at 1.7 GPa, to 650.660 °C at 2.5 GPa, to 600.640 °C at 3 GPa, and to 550.600 °C at 3.5 GPa. The location of the reaction in P-T-space is consistent with low-pressure experimental data of Chernosky et al. (1985), and is in reasonable agreement with the “conventional” high-pressure experiments of this study. The new experimental results were used to refine the existing thermodynamic properties of talc within the framework of the Holland and Powell (1998) database. The standard state enthalpy and entropy amount to Hof298= 5912.358 kJ/mol and So298 = 239.1 J/(K·mol). The refined standard entropy is about 9% lower than the entropy obtained calorimetrically. When the clinoenstatite-orthoenstatite transition is taken into account, So 298 of talc improves by ~6 J/K. We assume that a further increase of the standard state entropy of talc can be achieved by varying the activity of H2O in the fluid as a function of pressure and temperature.
Drag Reduction and Mechanical Degradation of Poly(ethylene oxide) in Seawater

Polymer induced turbulent drag reduction in a rotating disk apparatus was investigated using four different molecular weights of nonionic poly(ethylene oxide) (PEO) in synthetic seawater for potential application to cold water piping in the Ocean Thermal Energy Conversion (OTEC) system. The linear correlation between polymer concentration (C) and C/DR for different molecular weights of PEO and a universal correlation are obtained. In addition, to measuring the drag reduction efficiency change during the operation period, the drag reduction behavior is measured as a function of time, and the results obtained from this experiment are then correlated with Brostow’s equation for polymer degradation. From this study, the drag reduction effect induced by polymer additives is found to be applicable to the OTEC plant to reduce the pumping energy cost.
Optimized Synthesis of Vinyl Ether Sugars and Vinyl Glycosides through Transfer Vinylation Catalyzed by (4,7‐Ph2‐phen)Pd(OOCCF3)2

Sugar vinyl ethers and vinyl glycosides are conveniently synthesized by catalytic transfer vinylation with butyl vinyl ether, which serves as both the solvent and source of vinyl. The air‐stable catalyst (4,7‐diphenyl‐1,10‐phenanthroline)Pd(OOCCF3)2 is prepared in situ from commercially available components.