Miracle-dz/UniFAR-FTUs huggingface dataset:
Critical lines and phase coexistence of polymer solutions: A quantitative comparison between Wertheim’s thermodynamic perturbation theory and computer simulations

We consider the vapor–liquid phase equilibria of binary mixtures of a model bead–spring polymer dissolved in a solvent made of single monomers. We employ Wertheim’s thermodynamic perturbation theory of first order (TPT1), with the properties of the monomer fluid described by the mean spherical approximation and the effect of the attractions considered within a van der Waals one fluid approximation. The results of the TPT1 theory are quantitatively compared to grand canonical Monte Carlo simulations. To this end, we obtain full critical lines all the way from the critical point of the pure polymer to the critical point of the pure monomer. Pressure–composition and pressure–temperature slices are also obtained. At low pressures, we find rather good agreement between simulation and theory for the coexistence liquid densities and compositions. At higher pressures, however, the results are far less satisfactory, as the critical pressures are highly overpredicted.
Avaliação do neurodesenvolvimento de crianças expostas verticalmente ao víruz Zika assintomáticas ao nascimento e sua relação com o período de exposição durante a gestação

An epidemic outburst of Zika virus emerged in Brazil in the beginning of 2015. With the emerging cases came a lot of discussion about its congenital syndrome and the type of malformations the fetuses could present. There is a small amount of data on the literature regarding the medium and long-term outcomes, and also of the correlation between the severity of the development abnormalities with the time of infection during pregnancy. Some Zika virus exposed newborns present a severe neurologic disability resulting in an important developmental delay. However, others were asymptomatic at birth and little is known regarding possible future neurological damages. The aim of this study was to analyze the neurodevelopment outcome on these exposed and asymptomatic newborns, correlating the abnormalities found with the time at which the exposition occurred in utero. A prognostic study was performed in a cohort that is being followed as part of a project already approved by the Ethics Committee of the institution. The newborns were evaluated at 12 months of life with the Bayley Scales of Infant and Toddler Development 3rd Edition. The results were correlated with the gestational trimester in which the infection occurred. A total of 97 newborns were included on the study; 36.1% have presented involvement in at least one domain evaluated by the Bayley Scales of Infant and Toddler Development 3rd Edition. From those affected infants, 91.4% presented some language delay. In conclusion, there was and even distribution of the abnormal scores when compared to the gestational period however, we could see a slight increase in the infection rate during the first trimester. We could also notice a bigger language involvement in our group of patients, since they showed an increasing of the abnormal score proportion within the normal range but closer to the inferior cut This finding could be an indication of a future cognitive impairment, reinforcing the importance of a meticulous neurodevelopmental follow-up consults for this group of patients. It is also of great importance to encourage more studies that can access the long term consequences of the Zika virus infection
Phosphonium ionenes from well-defined step-growth polymerization: thermal and melt rheological properties

Step-growth polymerization of ditertiary phosphines with dibromoalkanes enabled the synthesis of novel phosphonium ionenes. In situ FTIR spectroscopy monitored the increase in absorbance as a function of time at 1116 cm−1, which corresponded to the polymeric P+–Ph stretch. Aqueous size-exclusion chromatography (SEC) provided absolute molecular weights and confirmed expected molecular weight growth for difunctional, step-growth polymerization. Phosphonium ionenes exhibited improved thermal and base stability compared to ammonium ionenes, which was attributed to the propensity of the ammonium cation towards Hofmann elimination. Melt rheology examined phosphonium ionene viscous flow and the influence of charge density on melt viscosity as a function of shear rate and temperature. Time–temperature superposition (TTS) resulted in both master curves and pseudomaster curves depending on phosphonium ionene composition. Two primary relaxations occurred: (1) onset of long-range segmental motion at Tg, and (2) relaxation attributed to electrostatic interactions. Higher charge densities shifted these two relaxations to longer time scales and increased flow activation energies. Phosphonium ionenes also readily bound pDNA effectively (± ratios of 1), and base stability suggested applications in energy generation.
Phosphate recovery from animal manure wastewater by struvite crystallization and CO2 degasification reactor

Abstract The problem of phosphorus discharge is related to environmental protection and food security. Struvite crystallization is a useful technology for phosphate recovery from wastewater. In the research, struvite crystallization process with CO2 degasification continuous U-shape reactor (CUSR) was application for phosphate recovery from animal manure wastewater. The result indicated PO43--P recovery ratio could achieve 47-53% without magnesium addition when CUSR hydraulic retention time controlled at 60 min. With extra magnesium addition, PO43--P recovery ratio could significant achieve 80-86% at magnesium addition amount 57.5 mg/dm3. PHREEQC modeling predictions trend of struvite crystallization was close to CUSR experimental results. The modeling calculation can provide a theoretical guide for operational parameters design. For seeding technology, high phosphate recovery efficiency was obtained and preformed struvite was the most effective seeding material. Surface characterization analysis demonstrated the dominant composition of chemical solids was struvite. Water extraction analysis indicated chemical solids recovery from animal manure wastewater could release PO43--P slowly and be available as slow-release fertilizer. Abstrakt Problem uwalniania fosforu jest związany z ochroną środowiska i bezpieczeństwem żywności. Krystalizacja struwitu jest przydatną technologią odzysku fosforanów ze ścieków. W opisanych badaniach proces krystalizacji struwitu zastosowano do odzyskiwania fosforanów z gnojowicy, do tego celu wykorzystano reaktor ciągłego odgazowywania CO2 w kształcie litery U (CUSR). Wyniki wskazują, że wskaźnik odzysku PO43- może osiągnąć 47-53% P bez dodatku magnezu, gdy kontrolowany, hydrauliczny czas retencji CUSR wynosi 60 min. Po wprowadzeniu magnezu w ilości 57,5 mg/dm3 wskaźnik odzysku PO43- może osiągnąć 80-86% P. Przewidywania modelu PHREEQC dotyczące krystalizacji struwitu był bliskie wynikom doświadczalnym CUSR. Obliczenia teoretyczne z wykorzystaniem modelu mogą stanowić wskazówkę do ustalania rzeczywistych parametrów eksploatacyjnych. Struwit otrzymany z gnojowicy może mieć zastosowanie w nasiennictwie. Analiza ekstrakcyjna wykazała, że materiał ten może powoli uwalniać PO43-P i dzięki temu znajduje zastosowanie jako nawóz.
Synthesis, NMR Spectroscopic Characterization and Polysiloxane‐Based Immobilization of the Three Regioisomeric Monooctenylpermethyl‐β‐cyclodextrins and Their Application in Enantioselective GC

2I−VI,3I−VII,6I−VII-Eicosa-O-methyl-2I-O-(oct-7-enyl)cyclomaltoheptaose, 2I−VII,3I−VI,6I−VII-eicosa-O-methyl-3I-O-(oct-7-enyl)cyclomaltoheptaose, and 2I−VII,3I−VII,6I−VI-eicosa-O-methyl-6I-O-(oct-7-enyl)cyclomaltoheptaose were synthesized by selective introduction of an oct-7-enyl group at one of the O-2, O-3, or O-6 positions of selectively methylated cyclomaltoheptaose (β-cyclodextrin, CD) and, depending on the synthetic route, by a subsequent permethylation step. Each of the regioisomeric mono-oct-7-enylated permethylated β-cyclodextrin derivatives was anchored by hydrosilylation to a hydridomethyldimethylsiloxane copolymer to yield unambiguously O-2-, O-3-, and O-6-bonded chiral stationary phases (CSP) of Chirasil-Dex, which were evaluated in enantioselective gas chromatography (GC). O-6-Chirasil-Dex displayed slightly inferior enantioselectivity relative to either O-3- or O-2-Chirasil-Dex. The statistical synthesis of the CSP by mono-oct-7-enylation of β-CD under varying reactions conditions (base, solvent), without the use of hydroxy group protection chemistry, furnished a mixture of O-6- and O-2-Chirasil-Dex in dimethylformamide and predominantly the O-2-regioisomer in dimethyl sulfoxide. Chirasil-Dex, previously formulated exclusively as the O-6 regioisomer, should be revised as an O-2- and O-6-Chirasil-Dex mixture. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Aqueous Dispersions of Silane-Functionalized Laponite Clay Platelets. A First Step toward the Elaboration of Water-Based Polymer/Clay Nanocomposites

Mono- and trifunctional organo alcoxysilane derivatives carrying a terminal reactive methacryloyl group have been used as reagents for the chemical modification of synthetic Laponite clay platelets in toluene. Qualitative evidence of the presence of chemically attached silane molecules was provided by Fourier transform infrared and 29Si and 13C solid-state NMR spectroscopies. Quantitative data (grafted amount and grafting yield) were also obtained by means of elemental and thermogravimetric analysis. While the trifunctional coupling agent was grafted on the clay edges in the form of oligomers pillaring the clay stacks, the monofunctional derivative selectively attached to the individual clay sheets as confirmed by X-ray diffraction and Brunauer−Emmett−Teller measurements. In agreement with these findings, only the clay stacks grafted using the monofunctional coupling agent could be satisfactorily redispersed into water. The aqueous suspensions of the grafted colloidal disks were characterized by small-ang.
Unified defect model and beyond

The unified defect model has been successful in explaining a wide variety of phenomena as oxygen or a metal is added to the III–V surface. These phenomena cover a range from a small fraction of a monolayer of adatoms to practical III–V structures with very thick overlayers. The tenets of the unified defect model are outlined, and the experimental results leading to its formulation are briefly reviewed. InP levels 0.4 and 0.1 eV and GaAs levels 0.7 and 0.9 eV below the conduction‐band minimum (CBM) are associated with either missing column III or V elements. In InP, it has been found possible by a number of workers to ’’switch’’ between the two defect levels by variations in surface processing, temperature, and/or selection of the deposited atom. The need to apply the proper concepts for surface and interface chemistry and metallurgy is recognized, and the danger of using solely bulk concepts is emphasized. The reason for this is examined for certain cases on an atomic level. The need for new fundamental a.
Guanidine Hydrochloride/ZnI2 as Heterogeneous Catalyst for Conversion of CO2 and Epoxides to Cyclic Carbonates under Mild Conditions

In this article, the combination of guanidine hydrochloride with co-catalyst ZnI2 proved to be a highly efficient heterogeneous catalyst for the environmentally benign, solvent-free synthesis of cyclic carbonates under mild reaction conditions. The effects of different co-catalysts as well as reaction parameters including catalyst loadings, CO2 pressure, reaction temperature, and reaction time on the coupling reaction of CO2 to propylene oxide were thoroughly investigated. With the molar ratio of guanidine hydrochloride to ZnI2 at 5:1, excellent yield (94%) and selectivity (≥99%) of propylene carbonate were obtained under 100 °C and at 1 MPa for 1.5 h. Additionally, ZnI2 could be recycled, but because of the washing loss of guanidine hydrochloride, there was a slight decrease in the yield of propylene carbonate. Gratifyingly, the activity of the catalytic system could be restored by adding additional 20 mol% of fresh guanidine hydrochloride, thus exhibiting excellent recyclability of the ZnI2 catalyst. Moreover, the binary catalysts were also versatile when using other epoxides for CO2 cycloaddition. A possible reaction mechanism was proposed wherein guanidine hydrochloride plays a dual role in activating CO2 and epoxide, and ZnI2 activated epoxide, simultaneously. The synergistic effect of guanidine hydrochloride and ZnI2 ensure the reaction proceeds effectively.
Size-selective Raman spectroscopy of carbazole-(Ar)n clusters at sub-wave-number resolution

Size‐selective Raman spectra of carbazole–(Ar)n clusters (n=0–14) obtained between about 1305 and 1325 cm−1 by mass‐selective ionization‐loss stimulated Raman spectroscopy are reported. The spectra are interpreted with respect to vibrational energy flow and argon evaporation, and are compared with vibronic spectroscopic results on the species.
STUDENT INFORMATION AI CHATBOT

-Automatic conversation system is an intelligent human machine interaction using natural language. Main goal of it is to allow the user and machine to make a natural harmonious conversation. Thus enabling the machine to recognize human motivation and to respond accurately, is not only an important manifestation of advanced intelligence, but also a very challenging work in harmonious human interaction field [1]. A conversation system consists of speech recognition, speech synthesis, and dialogue management and conversation generation. In this research, we focus on automatic generation of conversation between a computer and a human being with little knowledge of the computer.In this paper, we influenced a PC to end up a preparation to accomplice of a man who isn't great at discussion, to wind up a band together with a man. Therefore, in this research, we are focusing specifically on “chat" by developing an interactive AI which converse mainly by using machine learning. We perform a word unit prediction by using “Hill Climbing” algorithm and based on relevancy ranking, the relevant conversation is made.Our main focus, is to build a Student chat bot which helps the colleges to have 24*7 automated query resolution. This helps the students to have the right information from the trusted source. Also the administrationof information is made easy for the institutions.
BEHAVIOR OF TETHERED POLYELECTROLYTES IN POOR SOLVENTS

Using scaling theory and a two-dimensional self-consistent field calculation (SCF), we determine the morphology and phase behavior of charged polymers tethered by one end onto a flat substrate, and immersed in a poor solvent. For degrees of ionization, α, below a critical value, α*, the effects of the poor solvent dominate and the tethered chains collapse into pinned micelles on the planar surface. For values of α>α*, the chains extend to form a laterally uniform layer. This collapsed-to-stretched transformation constitutes a first-order phase transition. The specific routes to this transition are dependent on the relative solvent quality, and are described via the scaling theory. The structure of the layers above and below α* can be visualized through the polymer density profiles, which are obtained from the SCF calculations. The SCF calculations also show agreement with predictions from the scaling analysis.
Electrochemical Promotion of CH4 Combustion over a Pd/CeO2–YSZ Catalyst

The phenomenon of electrochemical promotion of catalysis (EPOC) has been demonstrated on palladium supported catalysts using ceria and yttria‐stabilised zirconia as solid electrolyte. SEM, XRD, linear voltammetry and AC impedance spectroscopy have been used to study this double electrolyte system. Electrochemical catalysts were also used to promote the methane combustion reaction leading to one of the highest faradaic efficiency reported for this reaction (Λ = 764). Thus, the catalytic activity of palladium was found to increase over 450% via electrochemical transference of oxygen promoting ions from the solid electrolyte to the catalyst film.
Analysis and evolution of air quality monitoring networks using combined statistical information indexes

In this work, we present combined statistical indexes for evaluating air quality monitoring networks based on concepts derived from the information theory and Kullback–Liebler divergence. More precisely, we introduce: (1) the standard measure of complementary mutual information or ‘specificity’ index; (2) a new measure of information gain or ‘representativity’ index; (3) the information gaps associated with the evolution of a network and (4) the normalised information distance used in clustering analysis. All these information concepts are illustrated by applying them to 14 yr of data collected by the air quality monitoring network in Santiago de Chile (33.5 S, 70.5 W, 500 m a.s.l.). We find that downtown stations, located in a relatively flat area of the Santiago basin, generally show high ‘representativity’ and low ‘specificity’, whereas the contrary is found for a station located in a canyon to the east of the basin, consistently with known emission and circulation patterns of Santiago. We also show interesting applications of information gain to the analysis of the evolution of a network, where the choice of background information is also discussed, and of mutual information distance to the classifications of stations. Our analyses show that information as those presented here should of course be used in a complementary way when addressing the analysis of an air quality network for planning and evaluation purposes.
Effect of starch type on selectivity of cationic flotation of iron ore

Cationic flotation is one of the most widely accepted technologies for upgrading siliceous iron ore using polysaccharides (mainly starches) as depressing agents for iron bearing minerals while floating silica with amines. In this paper, a group of starches are investigated as depressants for haematite. These starches are wheat, corn, rice, potato and dextrin. The role of starch type on the selectivity of the separation process has been studied through zeta potential, adsorption measurements as well as flotation tests. The effects of type of starch and pH of the medium have been studied. The results indicate that the selectivity of the separation process is strongly affected by the type of starch used, where better results are obtained with corn starch or wheat starch in comparison to the other types. Fourier transform infrared spectroscopy measurements indicated that the interaction between starches and haematite surface is intermolecular interaction.
Measurement of Neutron-Production Double-Differential Cross Sections for Nuclear Spallation Reaction Induced by 0.8, 1.5 and 3.0 GeV Protons

Neutron-production double-differential cross sections were measured for the spallation reaction induced by 0.8, 1.5 and 3.0GeV protons on C, Al, Fe, In and Pb targets. The experiments were performed by time-of-flight technique with a typical flight path length of 1 m, and the cross sections were obtained with energy resolutions better than 8% at neutron energies below 100MeV. The experimental data were compared with the results of calculation codes based on an intranuclear-cascade-evaporation model. Adoption of the in-medium effect on nucleon-nucleon cross section in the cascade calculation improves the agreement between the calculated results and experimental data particularly in the case of 0.8-GeV proton incidence. For protons above 1GeV, however, the calculations typically twice overestimate the cross sections in the emitted neutron energy region of 10 to 30MeV.
Room‐Temperature Printing of Organic Thin‐Film Transistors with π‐Junction Gold Nanoparticles

Printing semiconductor devices under ambient atmospheric conditions is a promising method for the large‐area, low‐cost fabrication of flexible electronic products. However, processes conducted at temperatures greater than 150 °C are typically used for printed electronics, which prevents the use of common flexible substrates because of the distortion caused by heat. The present report describes a method for the room‐temperature printing of electronics, which allows thin‐film electronic devices to be printed at room temperature without the application of heat. The development of π‐junction gold nanoparticles as the electrode material permits the room‐temperature deposition of a conductive metal layer. Room‐temperature patterning methods are also developed for the Au ink electrodes and an active organic semiconductor layer, which enables the fabrication of organic thin‐film transistors through room‐temperature printing. The transistor devices printed at room temperature exhibit average field‐effect mobilities of 7.9 and 2.5 cm2 V−1 s−1 on plastic and paper substrates, respectively. These results suggest that this fabrication method is very promising as a core technology for low‐cost and high‐performance printed electronics.
Adsorption Potential of Lead(II) Ions from Aqueous Solutions onto Capsicum annuum Seeds

Abstract The purpose of this work was to evaluate the adsorption potential of Capsicum annuum seeds, in a batch system for the removal of lead(II) ions from aqueous solutions. The experimental results showed that this agricultural by‐product was effective in removing lead(II) ions. The FT‐IR analysis indicated that the mechanism involved in adsorption of lead(II) ions by seeds of C. annuum was mainly attributed to lead(II) binding of amino and hydroxyl groups. Adsorption equilibrium approached within 40 min. The adsorption data fitted well to the Langmuir isotherm model. The maximum adsorption capacity (q max) was 1.87×10−4 mol g−1. Pseudo‐second‐order kinetic model was applicable to all the adsorption data over the entire time range. The thermodynamic parameters indicated that the adsorption process is spontaneous since Gibbs free energy values are negative, which are between −26.92 and −30.77 kJ mol−1 at the temperature range of 20–50°C.
Surface Chemistry of Semiconductor Nanocrystals

The fluorescence properties of CdSe semiconductor nanocrystals are investigated after surface modification with different kinds of molecular ligands. We show that the fluorescence is decreasing after removal of the excess ligands because the ligands are usually not strongly bound to the surface. The ligand exchange by multi-functional dye labelled polymer ligands allows to investigate the nanocrystal–ligand interaction by fluorescence resonance energy transfer (FRET-) experiments. Individual nanocrystal-dye complexes are investigated by single particle fluorescence microscopy and spectroscopy to show large inhomogeneities among the prepared structures.
Effect of Ball Milling on the Hydrolysis of Microcrystalline Cellulose in Hot-Compressed Water

Ball milling leads to a considerable reduction in cellulose particle size and crystallinity, as well as a significant increase in the specific reactivity of cellulose during hydrolysis in hot-compressed water (HCW). Cryogenic ball milling for 2 min also results in a significant size reduction but only little change in cellulose crystallinity and specific reactivity during hydrolysis. Therefore, crystallinity is the dominant factor in determining the hydrolysis reactivity of cellulose in HCW while particle size only plays a minor role. Ball milling also significantly influences the distribution of glucose oligomers in the primary liquid products of cellulose hydrolysis. It increases the selectivities of glucose oligomers at low conversions. At high conversions, the reduction in chain length plays an important role in glucose oligomer formation as cellulose samples become more crystalline. An extensive ball milling completely converts the crystalline cellulose into amorphous cellulose, substantially enhancing the formation of glucose oligomers with high degrees of polymerization. © 2010 American Institute of Chemical Engineers AIChE J, 2011