Miracle-dz/UniFAR-FTUs huggingface dataset:
Three-body effects in hydrogen fluoride: survey of potential energy surfaces

The potential energy surface for trimers of hydrogen fluoride is examined for multiple arrangements of the three-molecule cluster. Several established approaches to model the potential energy are examined, including a strictly pairwise additive potential, an established polarizable potential model, another, strictly three-body polarizable model, and a three-body potential recently fitted to accurate ab initio calculations. These potential surfaces are compared to MP2/6-311++G** and SCF/6-311++G**ab initio calculations performed here for each configuration. In each case the overall trimer potential is examined, as well as the three-body contribution to it (obtained by subtracting the sum of the interactions taken pairwise). The effective pair potential has some correspondence to the ab initio calculations, although it generally displays a shallower minimum energy. The established polarizable model has a more repulsive core that compensates for a deeper attractive well that it has adopted to better describe phase-coexistence data. In contrast, the new three-body polarizable model shows better correspondence with the ab initio potential-energy surface.
Influence of Process Variables on the Reactivity of Low Formaldehyde Emission Urea-Formaldehyde Resin

One of the important characteristics of the thermosetting resins such as urea-formaldehyde resin is the cure property. This is an invaluable characteristic for determining the processing capabilities of the resin. Differential scanning calorimetry (DSC) measurements are ideally suited to achieve this end. This paper presents the results of the effect of process variables on the enthalpy of cure of a low formaldehyde emission UF resin prepared by a four-stage process as described in the text. Response surface methodology (RSM) was used to design and the analyze the experiments. Urea (U) was added to the reaction mixture according to a pre-determined program of varying the number of additions and the duration between the additions during the second stage of the process. A mathematical relationship between the process variables and enthalpy of cure was established. The urea-formaldehyde (UF) resin was prepared under optimum conditions. Experiments were performed with the resin so prepared to determine the energy of activation of the curing reaction catalyzed by ammonium chloride.
CRUNCH: a phase refinement program for high-resolution macromolecular structures

A phase refinement program for high-resolution macromolecular structures is described. The mean phase error of an initial structural solution can often be as large as 60° prior to attempting a refinement, but the CRUNCH program procedure may allow one to reduce this phase error to 10 or 20° for all data prior to actually inspecting any map to see how well it may fit a structural model. The procedure is similar to the real/reciprocal space refinement loop incorporated in the half-baked algorithm described by Sheldrick [Sheldrick & Gould (1995). Acta Cryst. B51, 423–431. ] Refinement results are presented for nine different structures which diffract to better than 1.2 A resolution. The program and test data are available via anonymous ftp (nexus.hwi.buffalo.edu).
Microwave-Assisted Organocatalytic Anomerization of α-C-Glycosylmethyl Aldehydes and Ketones

The use of l-proline (30 mol %) and MW irradiation (13 W) with cooling promotes in a few hours the almost quantitative anomerization of α-C-glycosylmethyl aldehydes into β-isomers. An open-chain enamine-based mechanism is postulated for this transformation. The anomerization of α-ketones was instead achieved by the pyrrolidine/TFA couple and MW irradiation at 120 °C (enamine mechanism) and by DBU as Bronsted base (enolate mechanism).
Effect of nitrogen source on biodegradation of crude oil by a defined bacterial consortium incubated under cold, marine conditions

Studies have been carried out using a defined bacterial consortium which degrades crude oil under cold, marine conditions. The type of nitrogen supplement (i.e. ammonium versus nitrate) in the artificial sea water medium used in the experiments affected the degree of oil biodegradation observed, and was correlated with spent culture medium pH. Supplementation with ammonium led to progressive acidification of cultures, whereas nitrate amendment resulted in a neutral culture medium. The presence of ammonium in cultures incubated with the full consortium of strains was correlated with decreased aromatic fraction biodegradation, suggesting that aromatic degradation is sensitive to pH and possibly to by-products of saturate fraction biodegradation. The pH effect was shown to be caused primarily by one or more of the three saturate-degrading bacterial strains in the inoculum, when incubated in the presence of ammonium, while the aromatic-degrading strains did not acidify culture medium to the same degree. Acidi.
Relationship between distribution of substituents and water solubility of O‐methyl cellulose

The solubility behavior of O-methyl cellulose (MC) in water was investigated in terms of the distribution of substituents along the cellulose chain as well as in the anhydroglucose (AHG) units. For this purpose, three different types of MC samples were prepared by respective homogeneous reaction, i.e. (i) methylation of cellulose acetate (CA) prepared from cellulose triacetate (CTA), followed by deacetylation, (ii) methylation of CA prepared by direct acetylation of cellulose in a 10% LiCl–dimethylacetamide (DMAc) solution, followed by deacetylation, and (iii) methylation of cellulose with dimethyl sulfate in a 10% LiCl–DMAc solution. Their water solubility was compared with that of MC samples prepared by the alkali cellulose process, i.e., by the heterogeneous reaction, including commercial products. It was found that water-soluble MC samples prepared by the alkali cellulose process exhibit a thermally-reversible sol-gel transition in aqueous solution, but all of the MC samples preapred homogeneous reactions show a normal phase separation in aqueous solution. This result gives a direct support for the consideration that the highly substituted glucose sequences present in the commercial MC act as “crosslinking loci” on warming. The distribution of substituents in the AHG units was estimated by 13C-NMR method. The results on the water solubility of MC were also discussed in terms of the distribution of substituents in the AHG units.
A quarter-wave Y-shaped patch antenna with two unequal arms for wideband ultra high frequency radio-frequency identification (UHF RFID) operations

The radio-frequency identification (RFID) system which has become pervasive in the auto identification technology has been noticed to have several limitations. These limitations can be broadly divided into two major areas namely; application specific problems and general RFID problems. Application specific problems are common to the environment in which RFID tags are deployed such as metal, aqueous and irradiation environments. Whilst, the general problem of RFID tags include low gain, regional specifications and so on. In this paper, a new antenna prototype has been design and stimulated. The proposed antenna showed tendency of exhibiting improved gain from the previous RFID UHF antenna which is 0-1 dBi to -3 dBi and impedance bandwidth of 140 MHz. The proposed antenna is Y shaped patch with unequal monopole arms which are responsible for the different frequencies that the antenna operates and a quarter wavelengths was adopted rather than the popular half wavelength for size reduction. The fractional return-loss bandwidth for S11<10 dB and radiation efficiency are about 95% was obtained.
Poly(methacrylic acid) Hydrogel Films and Capsules: Response to pH and Ionic Strength, and Encapsulation of Macromolecules

Hydrogen-bonded multilayers of a neutral polymer (poly(N-vinylpyrrolidone), PVPON) with poly(methacrylic acid) (PMAA) were used as templates to introduce cross-links between PMAA layers using carbodiimide chemistry and ethylenediamine as a cross-linking agent. Upon exposure to high pH, PVPON is completely released from the hydrogel matrix, producing surface-attached PMAA hydrogels. When such hydrogels are deposited at the surface of silica particles, and the particle core is subsequently dissolved, hollow one-component hydrogel capsules are produced. PMAA hydrogel films and hollow capsules underwent reversible, large (factors of 2 or 3) changes in size in response to changes in solution pH and/or ionic strength. The capsules were used for entrapment and storage of macromolecules such as 500 kDa FITC-dextran by “locking” the capsule wall with an electrostatically associating polycation, poly-N-ethyl-4-vinylpyridinium bromide (QPVP). The release of the encapsulated macromolecules was achieved under high sal.
Formation of the TcN multiple bond from the reaction of ammonium pertechnetate with S-methyl dithiocarbazate and its application to the preparation of technetium-99m radiopharmaceuticals

The reaction of pertechnetate with the S-methyl ester of dithiocarbazic acid, H2N–NR–C(S)SCH3(R = H or CH3), in the presence of HCl and triphenylphosphine, affords the technetium(V) nitrido complex [TcNCl2(PPh3)2] in high yield. Derivatives of S-methyl dithiocarbazate of the type R1(R2)CN–NR3–C(S)SCH3, where R1=o-C6H4OH, C6H5, or CH3, R2= H or CH3, and R3= H or CH3, behave as sources of N3– groups, giving rise to a variety of technetium complexes containing the TcN multiple bond. These reactions apply equally well to the preparation of technetium-99m radiopharmaceuticals containing the TcN group, at the non-carrier-added level of nuclear medicine.
Characterization of Structural and Surface Properties of Nanocrystalline TiO2−CeO2 Mixed Oxides by XRD, XPS, TPR, and TPD

This work focuses on characterizing the structural and surface properties of TiXCe1-XO2 (TiO2−CeO2) mixed oxides using XRD, XPS, BET, H2-TPR, and NH3-TPD techniques. The TiXCe1-XO2 mixed oxides synthesized by the urea coprecipitation method showed unimodal nanoporous structure with pore sizes increasing from 3.7 nm for X = 0.9 to 5.3 nm for X = 0.1. Concomitant with their higher surface area and pore volume, the mixed oxides were nanocrystalline, about 4.0 nm in crystallite size when X = 0.9, and 4.8−5.4 nm when X = 0.1− 0.3, which are significantly smaller than TiO2 and CeO2 single oxides prepared by the same method (8.1 to 8.4 nm). A dominant anatase phase was detected by XRD when X was 0.9 or higher while a cubic fluorite phase was dominant when X was 0.3 or lower. Lattice parameters were changed by incorporating Ce into TiO2, and Ti into CeO2, respectively. This change indicates distortion of structure and was attributed to reduction of Ti4+ to Ti3+, and Ce4+ to Ce3+. XPS (Ce 3d, Ti 2p, O 1s) and H2-T.
Long-term tillage and crop rotation effects on soil quality, organic carbon, and total nitrogen

Van Eerd, L. L. , Congreves, K. A. , Hayes, A. , Verhallen, A. and Hooker, D. C. 2014. Long-term tillage and crop rotation effects on soil quality, organic carbon, and total nitrogen. Can. J. Soil Sci. 94: 303-315. Long-term studies allow for quantification of the effects of crop production practices, such as tillage and crop rotation, on soil quality and soil C and N stores. In two experiments at Ridgetown, ON, we evaluated the long-term (11 and 15 yr) effect of tillage system and crop rotation on soil quality via the Cornell Soil Health Assessment (CSHA) at 0-15 cm and soil organic C (SOC) and total N at 5-, 10-, and 20-cm increments to 120 cm depth. The CSHA soil quality score and SOC and total N were higher with no-till (NT) than fall moldboard plough with spring cultivation (conventional tillage, CT) and rotations with winter wheat [soybean-winter wheat (S-W) and soybean-winter wheat-corn (S-W-C)] compared with rotations without winter wheat. In both long-term trials, NT had ca. 21 Mg ha-1 more or 14% higher SOC than CT in the 0- to 100-cm soil profile, a trend which contrasts previous research in eastern Canada. Thus, the two long-term trial results at Ridgetown suggest that to improve soil quality and storage of C and N, growers on clay loam soil in southwestern Ontario should consider adopting NT production practices and including winter wheat in the rotation.
Determining unknown concentrations of nanoparticles: the particle-impact electrochemistry of nickel and silver

The developing field of particle-impact electrochemistry is rapidly establishing itself as a powerful tool for the interpretation of a wide range of phenomena associated with nanoparticles. In this article we present results showing the characterisation of nickel nanoparticles and, for the first time, a mixture of nanoparticles: in this case nickel and silver. The former are shown not to aggregate in aqueous solution whereas the latter do. We report a novel method for the determination on unknown concentrations of nanoparticles in a sample and demonstrate its use for both aggregating and non-aggregating nanoparticles.
Influence of Integrated Supply of Vermicompost and Zinc‐Eniched Compost with Two Graded Levels of Iron and Zinc on the Productivity of Geranium

Abstract Two pot experiments under greenhouse condition were carried out to study the influence of vermicompost and zinc‐enriched compost with two levels of iron and zinc on the productivity of geranium (Pelargonium graveolens). Joint application of vermicompost and zinc‐enriched compost was effective in increasing the herb and oil yield over sole application of iron and zinc. Combined application of vermicompost and zinc‐enriched compost gave better herb and oil yield in both the experiments. With application of vermicompost and zinc‐enriched compost with two graded levels of iron, higher N, P, and K concentrations were observed with application of vermicompost (5 g kg−1), vermicompost (5 g kg−1), and Fe 12.5 ppm+Zn‐enriched compost 2.5 g kg−1 soil, respectively, over control. Highest reduction in soil pH was observed with an application of vermicompost at 5 g kg−1 soil; maximum soil organic carbon content was also recorded in the same treatment. In experiment II, joint application of vermicompost, zinc‐enriched compost, and graded levels of zinc recorded highest N, P, and K concentration with treatments of Zn (15 ppm)+vermicompost (2.5 g kg−1), vermicompost (5 g kg−1), and Zn (15 ppm)+vermicompost (2.5 g kg−1 soil), respectively. Nitrogen, P, and K content increased by 36, 125, and 305%, respectively, with these treatments over the control. Chemical constituents of geranium oil such as cis‐rose oxide, isomenthone, linalool, citronellyl, geranylformate, geranyl, and epi‐γ‐eudesmol were significantly improved by combined application of Zn with vermicompost and Zn‐enriched compost as compared to sole application of Zn. Similar effects were observed with Fe in combination with vermicompost and Zn‐enriched compost on most of the chemical constituents of geranium oil. Physicochemical properties of the soil were also improved as macro‐ and micronutrient availability markedly increased in both the experiments because of combined application of vermicompost and Zn‐enriched compost with two levels of Zn and Fe.
Characterization and dewatering evaluation of acid mine drainage sludge from ammonia neutralization

A major problem in the active treatment of acid mine drainage (AMD) is the generation of large volumes of sludge through pH neutralization and subsequent metal precipitation. The sludge typically contains a low concentration of solids, resulting in associated handling and disposal difficulties. Anhydrous ammonia is one reagent commonly used to neutralize AMD due to its quick reaction rate, easy implementation, and relatively low chemical and operational costs. However, very limited information is available in the literature related to the detailed characterization and dewaterability of ammonia-treated AMD sludge. In this study, sludge was collected from an AMD treatment facility where ammonia neutralization was used. The sludge characteristics included high pH and alkalinity, high total Fe and Al, elevated sulfate, and low solids content (0.72 ± 0.24%). Coagulants and flocculants were not effective in reducing the settled sludge volume. Based on filtration tests, ammonia-treated AMD sludge demonstrated re.
Metal-induced effects on the glass transition kinetics of glassy Se70Te30 alloy

The calorimetric measurements have been made in glassy Se70Te30 and Se70Te28M2 (M = Ag, Cd, and Zn) alloys using non-isothermal differential scanning calorimetry technique to see the effects of Ag, Cd, and Zn additives on the glass transition kinetics of binary Se70Te30. From the heating rate dependence of glass transition temperature, T g, different kinetic parameters of glass transition have been evaluated. The composition dependence of glass transition temperature T g and the related activation energy (Et ) is also discussed.
Analysis of the current linearity at low illumination of high‐efficiency back‐junction back‐contact silicon solar cells

The relation between current and illumination intensity of three structures of high‐efficiency back‐junction back‐contact silicon solar cells was analyzed. Both, n‐type cells with non‐diffused front surface and p‐type cell with floating n‐emitter show a pronounced non‐linearity due to strong illumination dependence of the passivation quality of the non‐diffused surface and the floating junction respectively. Quantum efficiency (QE) of this cell type drops significantly for the illumination lower than 0.5 suns. In contrast the QE of n‐type cells with n+‐front surface field (FSF) is linear. Low illumination current characteristics of all three of the analyzed structures could be well described by physical models. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
RELEASE OF PHENOLIC COMPOUNDS FROM BEAN FLOUR, BEAN-DERIVED CHIPS AND BLACK CHOKEBERRY JUICE AND CHANGES IN THEIR ANTIOXIDANT ACTIVITY DURING DIGESTION IN AN IN VITRO GASTROINTESTINAL MODEL

An in vitro gastrointestinal model, which simulates the conditions of the human digestive tract, was used in this work to determine the potential antioxidant activity in Jaś Karlowy bean flour, extruded Jaś Karlowy bean products (chips) and black chokeberry juice. The aim of the study was to investigate changes in the level of phenolic compounds and antioxidant activity under in vitro conditions which closely resemble those occurring in the human digestive tract. We examined the effect of human fecal flora on the antioxidant activity of products undergoing digestion, which are a rich source of antioxidant compounds. Results obtained in the research indicate that the in vitro gastrointestinal tract model applied in this work can be successfully used to study changes in the level of phenolic compounds. Our observations show that digestion of Jaś Karlowy bean flour, an extruded product from bean and black chokeberry juice in the gastrointestinal tract model has an influence on the antioxidant activity and the level of phenolic compounds in these products of Jaś Karlowy bean flour, extruded product from bean and black chokeberry juice. The highest antioxidant activity, approx. 30 mg Trolox/g during the digestion process, was noted for both flour and extruded bean products. All products examined were found to stimulate the growth of intestinal microorganisms, however black chokeberry juice decreased only the growth of bacteria from the Enterococcus species.
Laser-induced shockwave propagation from ablation in a cavity

The propagation of laser-induced shockwaves from ablation inside of cavities was determined from time-resolved shadowgraph images. The temperature and electron number density of the laser-induced plasma was determined from spectroscopic measurements. These properties were compared to those for laser ablation on the flat surface under the same energy and background gas condition. A theoretical model was proposed to determine the amount of energy and vaporized mass stored in the vapor plume based on these measurements.
Heterogeneous Interfacial Properties of Ink‐Jet‐Printed Silver Nanoparticulate Electrode and Organic Semiconductor

Nanoparticles are useful building blocks for modern electronic, electro-optic, and photovoltaic applications because they can be easily processed into large-area thin ﬁlms from solutions by inexpensive techniques such as spin-coating and ink-jet printing. [1–3] Although the electronic properties of individual nanoparticles have been thoroughly studied, [4,5] little attention has been paid to the characteristics of assembled nanoparticles in contact with electroactive materials, such as organic semiconductors. Printed thin-ﬁlm transistors (TFTs) composed of nanoparticles could be a good alternative to silicon-based technologies for use in large-area, ultra-low-cost, and ﬂexible electronics. Most research on nanoparticle-based printable transistors has been devoted to the production of current-carrying conductive features, such as channel electrodes and conductive lines. Printable conductive polymers and graphite pastes generally suffer from low conductivity (10–100 Scm (cid:1) 1 ) and/or chemical, thermal, and electrical instability. [6] Metal nanoparticles, on the other hand, have depressed melting points – owing to surface effects – and hence can be annealed to conductive ﬁlms at temperatures compatible with plastic electronics. [7–9] Noble-metal nanoparticles, such as gold and silver, which possess high electrical conductivity (on the order of 10 5 S cm (cid:1) 1 ) and operational stability, have been utilized to fabricate low-cost printed TFTs. Metal nanoparticles are generally protected by an organic ligand or polymer during synthesis to ensure that they do not prematurely coalesce into the dispersed state in solution. Electrically insulating metal-nanoparticle-assembled ﬁlms can be converted into electrically conductive ﬁlms by annealing. Because of this
Interaction between Oxygen Transfer Mechanisms in Lake Models

Dissolved oxygen (DO) distributions in stratified lakes can be simulated by a one-dimensional (vertical), deterministic, unsteady (time-variant) diffusion equation with surface gas transfer as a boundary condition and photosynthetic oxygen production as an internal source. Both surface gas transfer and vertical diffusion depend on turbulence near the water surface. The interaction between these two mechanisms, and photosynthetic productivity of dissolved oxygen in lake models is therefore studied analytically and numerically. The analytical solution of the DO transport equation in a semiinfinite medium is developed. Predicted DO concentrations at depth z are shown to depend on three dimensionless parameters, and the strength of net photosynthetic oxygen production is an important parameter in this analysis. The increases of DO concentrations due to photosynthesis are modulated by surface aeration and vertical diffusion in the lake. A numerical solution of the dissolved oxygen transport equation is also ob.
Unique core-shell structured SiO2(Li+) nanoparticles for high-performance composite polymer electrolytes

Core–shell structured SiO2 nanoparticles with controlled morphology were synthesized and used as functional fillers in Li+-conducting composite polymer electrolytes for lithium-ion polymer batteries. The composite polymer electrolytes prepared with poly(vinylidene fluoride-co-hexafluoropropylene) and core–shell SiO2(Li+) nanoparticles exhibited high ionic conductivity, good mechanical strength and favorable interfacial characteristics. Tests run on carbon/LiNi1/3Co1/3Mn1/3O2 cells with composite polymer electrolyte containing optimized SiO2(Li+) nanoparticles yielded excellent results in terms of capacity retention (95% after 100 cycles) and rate capability (167 mA h g−1 at 5 C rate).