Miracle-dz/UniFAR-FTUs huggingface dataset:
Effect of Copper on the Decomposition of Ethylene over an Iron Catalyst

Abstract The catalytic properties of a series of unsupported copper–iron powders of varying composition were investigated by using a probe reaction of ethylene and hydrogen at temperatures over the range 450 to 800°C. Analysis of both the gas-phase products and the solid carbon, mainly in the form of filamentous structures, produced during the reaction provided an in situ method for monitoring the changes in the nature of the bimetallic surfaces under reaction conditions. Although these metals exhibit only limited miscibility in each other the reaction between ethylene and hydrogen over the bimetallic powders resulted in higher carbon yields and altered selectivities to gas-phase products compared to that observed with the single components under the same conditions. The addition of only 2 wt% copper to iron caused a 20-fold increase in the amount of carbon filaments formed compared to that produced on pure iron at 600°C. This behavior cannot be rationalized simply by an increase in metal dispersion; instead, one may speculate that the presence of a small amount of copper is capable of inducing electronic perturbations in the iron atoms, which results in a modification in the chemisorption characteristics of ethylene on such a surface. The presence of hydrogen in the gaseous reactant was found to facilitate the interaction between the olefin and the bimetallic surface, resulting in increased yields of both solid carbon and ethane. It is suggested that during the interaction of hydrocarbons with metals the particles adopt a morphology in which there are at least two distinct faces; a set which are only capable of adsorbing and decomposing hydrocarbons, and others that will precipitate dissolved carbon in the form of graphite platelets. Under such circumstances there are always a set of faces that are completely free of deposited carbon and available for continued catalytic action.
Liquid phase hydrogenation of aniline in a trickle bed reactor

A rate equation is developed for the liquid phase hydrogenation of aniline over cylindrical catalyst pellets of 30% nickel deposited on clay in a trickle bed reactor. The equation takes into account external and internal diffusional limitations, and describes the experimental data adequately. The hydrogenation reaction is first order with respect to hydrogen and zero order with respect to aniline. Effectiveness factors are in the range 0.003-0.03. Apparent activation energy of the reaction is 12.7 kcal/mol and true activation energy is 39.6 kcal/mol.
SOLID-LIQUID MASS TRANSFER AT THE WALLS OF A RECTANGULAR AGITATED VESSEL

Rates of mass transfer between the walls of a rectangular agitated vessel and solution were studied by measuring the limiting current of the cathodic reduction of ferricyanide ion at the vessel wall. Variables studied were rotation speed of 45° pitched blade turbine impeller, physical properties of the solution and the presence of drag reducing polymer in lhe solution (Polyox WSR-301). The data were correlated for polymer free solution by the equation: Sh= 1.925 Sc0.33 Re0.5 Comparison of the present data with previous heat and mass transfer studies conducted in cylindrical vessels has shown that the mass transfer behaviour of agitated rectangular vessels lie between baffled and unbaffled agitated cylindrical vessels. Polyox addition was found to reduce the mass transfer coefficient by an amount ranging from 5.6 to 37% depending on polymer concentration. Practical implications of using drag reducing polymers in agitated vessels were discussed.
Experimental Study on the Effects of Natural Zeolite on Lead Toxicity, Growth, Nodulation, and Chemical Composition of Soybean

Lead (Pb) is one of the most dangerous contaminants that has been released into the environment over many years by anthropogenic activities. In the present study, the effect of zeolite on the Pb toxicity, growth, nodulation, and chemical composition of soybean (Glycine max L. var. Williams) was evaluated. Treatments consisted of factorial combination of three levels of zeolite (0, 2, and 5 g kg−1) and three levels of Pb (0, 10, and 25 mg kg−1) with three replicates in a completely randomized design. Lead application decreased shoot and root dry weights. Without any use of Pb, addition of zeolite increased shoot dry weight, iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentrations and the number and dry weight of root nodules. Moreover, the greatest value for these parameters was obtained by greatest level of zeolite application (5 g zeolite kg−1 soil). It is suggested that zeolite has positive effects on growth and chemical composition of soybean and reduces Pb toxicity in plant parts.
Lattice vibration characterization and magnetic properties of M-type barium hexaferrite with excessive iron

Nonstoichiometric M-type barium hexaferrite compounds, with nominal compositions BaFe12+xO19+1.5x (0⩽x⩽0.4), have been synthesized by spark plasma sintering technique. The electron probe microanalysis shows that the excessive trivalent iron (Fe3+) ions are in the lattices of BaFe12+xO19+1.5x compounds. Both Raman and FTIR spectra reveal that the excessive Fe3+ ions spin upward. They occupy the octahedron interstices similar to the FeO6 octahedron at the 12k site and the bipyramid interstices similar to the FeO5 bipyramid at the 2b site, in the x range of 0–0.3 and x=0.4, respectively. This explains well significant enhancement in the specific saturation magnetizations for BaFe12+xO19+1.5x with increasing the x in the range of 0–0.4. The gradual increase in the coercivities has been interpreted with the augment of Fe3+ concentration in unit cell.
Growth of lead iodide platelets for room temperature x-ray detection by the vapor transport method

Lead Iodide purified by zone refining, sublimation and evaporation and without purification was used as starting material for growing platelets by the vapor transport method. Growth was performed at vacuum and at 500 mmHg of Ar, during times from 10 to 25 days. Platelets grew at 200 -250 degree(s)C less than the source temperature, in the zone of maximum temperature gradient and perpendicular to the ampoule wall. Growth was performed several times and results were reproducible. Crystals have rectangular or hexagonal (0 0 1) faces, sizes up to 4x6 mm2 and thickness from 50 to 250 micrometers , an exceptional good optical clarity and reflecting surfaces. Purity and stoichiometry of starting materials were determined by Inductively Coupled Plasma and wet techniques. Platelets were characterized by optical microscopy. Radiation detectors were fabricated with them and detector current density and apparent resistivity were determined by I-V curves, giving results 300 pA/cm2 (30V) and 1013 (Omega) . cm. X-ray spectra were performed determining detector's energy resolution for different emissions, giving a resolution of 1 keV in the range of 10 - 20 keV radiations. According to electrical and spectrometric performance, optical microscopy and production yields, it was not necessary to use high purity starting material for obtaining excellent platelets. Correlation between optical and electrical properties of the crystals grown from this method and others previously grown from the melt are also discussed. Comparison between the growth of lead iodide platelets and mercuric iodide ones is included.
Biologically Active Glycosides from Asteroidea, IX. Steroid Oligoglycosides from the Starfish Asterias amurensis [cf.] versicolor Sladen, 2. Structure Elucidation of Two New Oligoglycoside Sulfates, Versicoside B and Versicoside C

In addition to the already known asteronylpentaglycoside sulfate (5) and ovarian asterosaponin 1 (6), two new genuine asterosaponins named versicoside B (3) and C (4) have been isolated from the starfish Asterias amurensis [cf.] versicolor Sladen and characterized. Their structures have been elucidated as the monosodium salt of 6α-[(O-β-D-galactopyranosyl-(13)-O-β-D-fucopyranosyl-(12)-O-β-D-galactopyranosyl-(14)-O-[β-D-quinovopyranosyl-(12)]-O-β-D-xylopyranosyl-(13)-β-D-quinovopyranosyl)oxy]-20ξ-hydroxy-3β-(sulfooxy)-5α,24ξ-ergost-9(11)-en-23-one (3) and the monosodium salt of 6α-[(O-β-D-fucopyranosyl-(12)-O-β-D-galactopyranosyl-(14)-O-[β-D-quinovopyranosyl-(12)]-O-β-D-xylopyranosyl-(13)-β-D-quinovopyranosyl)oxy]-20-hydroxy-3β-(sulfooxy)-5α,24ξ-ergost-9(11)-en-23-one (4). Apart from the conventional analytical methods, negative fast-atom bombardment (negative FAB) mass spectrometry was successfully used for the first time for determination and confirmation of the structure of the natural oligoglycoside sulfates. Biologisch aktive Glycoside aus Asteroidea, IX. — Steroid-Oligoglycoside aus dem Seestern Asterias amurensis [cf.] versicolor Sladen, 2. — Strukturermittlung von zwei neuen Oligoglycosidsulfaten, Versicosid B und C Neben den bereits bekannten Glycosiden Asteronpentaglycosidsulfat (5) und Ovar-Asterosaponin 1 (6) wurden zwei neue, Versicosid B (3) und C (4) genannte genuine Asterosaponine aus dem Seestern Asterias amurensis [cf.] versicolor Sladen isoliert und charakterisiert. Auf Grund chemischer und spektroskopischer Befunde wurden die Strukturen als Mononatriumsalz von 6α-[(O-β-D-Galactopyranosyl-(13)-O-β-D-fucopyranosyl-(12)-O-β-D-galactopyranosyl-(14)-O-[β-D-chinovopyranosyl-(12)]-O-β-D-xylopyranosyl-(13)-β-D-chinovopyranosyl)oxy]-20ξ-hydroxy-3β-(sulfooxy)-5α,24ξ-ergost-9(11)-en-23-on (3) und Mononatriumsalz von 6α-[(O-β-D-Fucopyranosyl-(12)-O-β-D-galactopyranosyl-(14)-O-[β-D-chinovopyranosyl-(12)]-O-β-D-xylopyranosyl-(13)-β-D-chinovopyranosyl)oxy]-20ξ-hydroxy-3β-(sulfooxy)-5α,24ξ-ergost-9(11)-en-23-on (4) ermittelt. Neben konventionellen analytischen Methoden lies sich erstmals die Fast-Atom-Bombardment-Massenspektrometrie mit negativen Ionen (negative FAB) erfolgreich fur die Bestimmung und Absicherung der Struktur der naturlich vorkommenden Oligoglycosidsulfate benutzen.
Combination of immunotherapy and radiotherapy in the treatment of brain metastases from non-small cell lung cancer

It was commonly assumed in the past that blood-brain barrier could efficiently prohibit penetration of large peptide molecules, such as monoclonal antibodies, including programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors. This belief has been recently revised by studies that demonstrate the presence of functional lymphatic vessels lining the dural sinuses. Furthermore, the activated circulating T cells have been shown to cross the blood-brain barrier. Such observations created strong rationale for attempts of immunotherapy for patients with brain metastases, used either alone or in combination with radiotherapy. The expected benefit from immunotherapy particularly refers to patients without targetable “driver” mutations who are not considered as candidates for novel targeted therapies. Current inference on efficacy and safety of combination of immunotherapy and radiotherapy in the treatment of brain metastases from non-small cell lung cancer (NSCLC) origins, in most, from the retrospective studies. The existing data suggest that use of immune checkpoint inhibitors (ICIs) with brain radiotherapy improves patients outcome, compared to brain radiotherapy alone. The available data also suggest that concurrent use of ICI and stereotactic radiation therapy (SRT) for brain metastases from NSCLC is tolerable and appears more effective than sequential combination of radiotherapy and ICI. Use of steroids appeared detrimental. Since a dependence between the risk of adverse events and type of ICI therapy as well as tumor pathology was found, further studies are required to establish optimal dosage, selection of drugs and sequence of ICI and brain radiotherapy in patients with brain metastases from NSCLC.
Growing Together: Community Coalescence and the Social Dimensions of Urban Sustainability

Urban sustainability is most often measured using a series of social, economic, and ecological indicators. Assessment methods for urban sustainability typically factor in the ecological dimensions of greenspace, such as biodiversity maintenance, stormwater management, and/or air quality—yet indicator schemas that consider only the ecological dimensions largely overlook the social benefits of some types of urban greenspace, particularly community gardens and orchards. This article makes the case that the process of community formation and strengthening that occurs in shared growing spaces is an important element of urban sustainability in its own right. Based on 55 interviews of community garden advocates, policy-makers, and development professionals involved in urban agriculture planning, this article traces the widespread understanding among practitioners that shared growing spaces strengthen social as well as environmental sustainability, though the social benefits are often difficult to measure. The latter concern was most frequently expressed by urban agriculture advocates who, after involvement in the political process, perceived the need for such metrics in order to communicate persuasively with planners and policy makers. The social values of shared growing spaces, at once self-evident to garden advocates and difficult for them to demonstrate with quantitative data, may be theorized by drawing on insights from sociology: A truly sustainable city requires community coalescence among diverse citizens, and such community is fostered particularly well in shared growing spaces.
DVB-T-Based Passive Forward Scatter Radar: Inherent Limitations and Enabling Solutions

This article investigates the target detection capability of a passive forward scatter radar (PFSR) exploiting a digital video broadcasting – terrestrial (DVB-T) transmitter as illuminator of opportunity. By means of theoretical and simulated analyses, it is shown that conventional processing schemes might suffer from significant performance degradation when exploiting orthogonal frequency division multiplexing (OFDM) waveforms of opportunity compared to other broadcast transmissions (e.g., frequency modulation radio broadcast). Specifically, the direct application of conventional processing approaches to the case of a DVB-T PFSR is demonstrated to yield: 1) a nonnegligible increase of the competing background level and 2) a steeper fading of the target response due to the intrinsic characteristics of the exploited waveforms of opportunity, above all the modulation scheme and the signal spectral characteristics. Therefore, appropriate signal processing techniques are proposed to avoid these effects which jeopardize the target detection capability. The conceived processing scheme exploits the digital nature of the employed waveforms and a subband approach for improving both the interference cancellation stage and the target signature extraction. The benefits of the proposed approach are illustrated by means of theoretical and simulated analyses. The application of the resulting processing scheme against experimental data proves its effectiveness in practical scenarios.
Material properties of p .. type GaAs at large dopings

We summarize the room‐temperature minority‐carrier mobility, minority‐carrier lifetime, and effective band‐gap shrinkage for p‐type GaAs at large dopings, as determined from measurements on heterostructure bipolar transistors and published literature. The minority‐carrier mobilities are significantly smaller than the majority‐carrier mobilities, the lifetime data show a change in dependence on doping at 1×1019 cm−3, and the effective band‐gap shrinkage is ≊5% at 1×1019 cm−3. The fits to electrical parameters described here should be of interest in modeling of minority‐carrier devices.
Size effect on the stability of Cu–Ag nanoalloys

Classical molecular dynamics (MD) simulations are used to study the phase stability of Cu–Ag nanoalloys based on the analysis of their thermodynamic mixing properties for both random and core-shell clusters as functions of nanoparticle size, temperature and composition. At 298 K, results for nanoalloys of increasing size at fixed composition suggest that alloying Cu and Ag is thermodynamically feasible only for a nanocluster size range, excluding very small ( < 1.8 nm) and large clusters (≳4 nm). In the size range of favourable alloy formation, Cu–Ag core-shell structures are more stable than random configurations, and the same conclusion holds for most of the composition range at fixed cluster size and 298 K. Varying temperature at fixed nanocluster size and fixed composition, core-shell structures are preferred up to the melting temperature of the nanoparticle. Also, we test an analytical model to predict the thermodynamic properties of mixing of nanoalloys using bulk enthalpies of mixing of the pure components and those of the corresponding bulk alloy. The enthalpies and Gibbs free energies of mixing obtained from the analytical model qualitatively agree with those obtained from MD simulations, especially when the nanoparticle size increases above 2.8 nm.
Effects of tillage practice and repeated urban compost application on bromide and isoproturon transport in a loamy Albeluvisol

We quantified the effects of tillage practice and repeated compost (municipal solid waste compost, MSW, and co‐compost of sewage sludge and green wastes, SGW, compared with a control plot without compost addition, CONT) application on bromide and isoproturon transport into the tilled horizon of a loamy Albeluvisol. To do this we conducted field measurements of near‐saturated hydraulic conductivity (K), bromide and isoproturon leaching in column experiments and batch isoproturon sorption measurements. While the K measurements showed that tillage practice had the major effect compared with the different organic amendments, with greater conductivities measured after ploughing and smaller Kvalues measured after sowing, the column leaching experiments showed no statistically significant effect of either the tillage practice or the compost amendments. The batch sorption coefficient, Kd, of isoproturon increased in the order CONT < MSW < SGW, while the leaching of isoproturon for the MSW and SGW was either equal, retarded or quicker compared with CONT. Rate‐limited sorption of isoproturon in the CONT and SGW treatments columns was found, and the overall dissipation of isoproturon increased in the order CONT < SGW < MSW. It was suggested that irreversible sorption as well as degradation occured during isoproturon leaching.
Morphological Control of Single‐Crystalline Silicon Nanowire Arrays near Room Temperature

Silicon has dominated solid-state electronics for decades and is now leading to other applications, ranging from nano/ microelectromechanical systems to optoelectronics, Si Raman laser, solar cells, and biological/chemical sensors. Indeed, Si-based structures are widely employed in diverse fields, and the trend they have in common is that the device size continues to be scaled down to give compact systems, enhanced performance, and even revolutionary properties. As a consequence, currently research into silicon nanowires (SiNWs) is an essential topic. In fact, key to the implementation of practical applications of SiNWs is nanometer-scale control of their morphology. Here we report the morphological control of single-crystalline SiNWs with respect to their orientation, diameter, and length achieved using a statistical electroless metal deposition (SEMD) method. We also indicate that the preferential orientation is the [100] direction, in contrast to previous reports. Compared with other growth methods, ours possesses the further advantages of being a nearroom-temperature process, catalyst free, and having no saturated dopant contamination. So far various methods to fabricate SiNWs have been reported, such as vapor–liquid–solid (VLS) growth, solid– liquid–solid (SLS) growth, oxide-assisted growth, vapor– solid–solid (VSS) growth, catalytic chemical vapor deposition (CVD), and others. Nevertheless, most methods often result in randomly oriented SiNWs, and their diameters and lengths have a wide distribution. More critically, SiNWs fabricated by the catalytic processes inevitably contain saturated dopants from the catalyst (in particular, the most popular catalyst is gold, an extremely lethal impurity for integrated circuits (ICs)) and typically the process temperature is above 800 8C, radically impeding their feasibility in the IC industry. As a result, in the work reported in this Communication we utilized a SEMD method to
Combined Preconcentrator/Recovery Column Design for Isopropyl Alcohol Dehydration Process

The design and control of a complete heterogeneous azeotropic distillation column system using cyclohexane (CyH) as entrainer has been presented by Chien et al. (Ind. Eng. Chem. Res. 2004, 43, 2160). In that study, the feed composition to the heterogeneous azeotropic column is assumed to be near the isopropyl alcohol (IPA) and water azeotropic composition (water at 31 mol % in that paper). However, for a typical waste IPA stream in the semiconductor industry where IPA is used as a cleaning agent, this waste stream is more diluted. Taking a typical waste IPA stream with equal molar of IPA and water as an example, design and control of the overall isopropyl alcohol dehydration process will be investigated. The resulting proposed design flow sheet is a two-column system which combines preconcentrator column and recovery column into a single column. This design adapted from Ryan and Doherty (AIChE J. 1989, 35, 1592) for their ethanol dehydration process not only minimizes the total annual cost but also is ver.
Synthesis of carboxymethyl potato starch and comparison of optimal reaction conditions from different sources

Carboxymethyl potato starch (CMPS) was synthesized under heterogeneous reaction conditions. The influences of etherification temperature, alkalization and etherification time, sodium hydroxide to monochloroacetic acid (MCA) molar ratio (nNaOH/nMCA), theoretical degree of substitution (DSt), the ratio of isopropyl alcohol (IPA) volume to starch mass (vIPA/mst) on degree of substitution (DS) and reaction efficiency (RE) of CMPS were investigated. Compared with the previous literature data, the results had significant difference for the optimal carboxymethylation conditions of potato starch from different sources. CMPS prepared under optimal conditions showed the highest DS and RE, which were 1.36 and 0.88, respectively. Furthermore, the RE value in this work is considerably higher than that reported in the literature. The time of alkalization and etherification were also discussed independently. In addition, CMPS was characterized by Fourier transform infrared spectrophotometry and scanning electron microscopy (SEM). Copyright © 2008 John Wiley & Sons, Ltd.
Minimal Differential Difference Realizations of Delay Differential, Differential Difference, and Neutral Delay Systems

Delay-Differential Equations (DDEs) are often used to represent control of and over large networks. However, the presence of delay makes the problems of analysis and control of such networks challenging. Recently, Differential Difference Equations (DDFs) have been proposed as a modelling framework which allows us to more efficiently represent the low-dimensional nature of delayed channels in a network or large-scale delayed system. Unfortunately, however, the standard conversion formulae from DDE to DDF do not account for this low-dimensional structure - hence any efficient DDF representation of a large delayed network or system must be hand-crafted. In this letter, we propose an algorithm for constructing DDF realizations of both DDE and DDF systems wherein the dimension of the delayed channels has been minimized. Furthermore, we provide a convenient PIETOOLS implementation of these algorithms and show that the algorithm significantly reduces the complexity of the model for several illustrative examples, including Neutral Delay Systems (NDSs).