Miracle-dz/UniFAR-FTUs huggingface dataset:
Optical sensing and chemometric analysis of soil organic carbon – a cost effective alternative to conventional laboratory methods?

Soil organic carbon (SOC) is frequently determined by the Walkley‐Black (WB) method. A limitation of the test is incomplete oxidation of the carbon fraction and underestimation of SOC. Automated dry combustion methods are expensive and slow. Optical sensing and chemometric analysis offer the potential of an economical method capable of quantifying SOC fractions. The aim of this study was to identify the best SOC analysis method to facilitate maximum sampling resolution based on the cost per sample, analytical accuracy and time. A comparative evaluation was made of five techniques; (1) the WB method, (2) total combustion by total organic C analyser, (3) infrared (IR) diffuse reflectance spectroscopy, (4) a portable spectroradiometer and (5) laboratory hyperspectral imaging. This involved assessing equipment costs, consumables and time to derive total analytical cost. The benefits were sample throughput and analytical accuracy. Instrumentation represented the largest input to analytical cost and for optical methods was governed by the spectral range. In contrast to dry combustion, this cost is offset by high sample throughput and minimal consumable requirements for IR spectroscopy and hyperspectral imaging. Hyperspectral imaging is identified as the most rapid technique with potential to scan about 720 samples per day at 90% less cost than the WB method. The opportunity cost of hyperspectral imaging is to forfeit some analytical accuracy associated with the dry combustion method. Dry combustion, despite its high cost per sample, incurs no further costs associated with updating prediction models or developing site or soil specific correction factors.
Influence of oxygen contents of carbohydrate dopants on connectivity and critical current density in MgB2 tapes

More recently, it has been reported that carbohydrate doping resulted in an effective substitution of carbon for boron in MgB2, and hence achieved significant flux pinning enhancement. However, the authors found that the oxygen amount in carbohydrate additives played an important role in improving Jc-B performance in MgB2. In this work, the effect of maleic anhydride (C4H2O3) and maleic acid (C4H4O4) dopants on the superconducting properties of in situ MgB2 tapes has been studied. Compared to the undoped counterpart, both doped tapes showed an enhancement of Jc values by more than an order of magnitude in high-field region; however, the transport Jc of C4H4O4 doped tapes was apparently lower than that of C4H2O3 added samples. The poor grain connectivity as a result of more MgO and voids formed during the reaction in C4H4O4 doped samples can be responsible for the reduced Jc values.
Experimental determination of electro-osmotic drag coefficient in Nafion membrane for fuel cells

The electro-osmotic drag coefficient in nafion 117 membrane is determined experimentally at different temperatures and water contents of the membrane. a pseudo-two-dimensional, steady-state diffusive model for water vapor transport through nafion membrane based on nonequilibrium membrane/gas diffusion layer interface is presented to determine the electro-osmotic drag coefficient and average water content. for the membrane in contact with water vapor, the electro-osmotic drag coefficient increases with increasing water content or water activity in the membrane. at the same water activity, temperature does not show influence on the electro-osmotic drag coefficient in the membrane in contact with water vapor. for the membrane in contact with liquid water on both sides, the electro-osmotic drag coefficient in the membrane increases linearly with temperature. high-frequency resistances of the cells using nafion 117 and 112 membranes are measured to evaluate the electro-osmotic drag coefficients obtained. the calculated membrane resistance based on a diffusive model agrees well with the experimental data under different operating conditions. (c) 2006 the electrochemical society.
On the Possibility of a Metallic Modification of Hydrogen

Any lattice in which the hydrogen atoms would be translationally identical (Bravais lattice) would have metallic properties. In the present paper the energy of a body‐centered lattice of hydrogen is calculated as a function of the lattice constant. This energy is shown to assume its minimum value for a lattice constant which corresponds to a density many times higher than that of the ordinary, molecular lattice of solid hydrogen. This minimum—though negative—is much higher than that of the molecular form. The body‐centered modification of hydrogen cannot be obtained with the present pressures, nor can the other simple metallic lattices. The chances are better, perhaps, for intermediate, layer‐like lattices.
Authenticity of fats and oils

Food authenticity has become a focal point attracting the attention of producers, consumers, and policy makers. Although in most cases adulteration of fats and oils does not pose a threat to public health, fundamental rights of consumers (right of correct information and buying “value-for-money”) are violated by fraudulent malpractice. Fraud is only economically viable, if a cheaper commodity can be made to resemble a genuine, more expensive product. The extent of adulteration that is possible is quite limited and, hence, the basic product that is being adulterated cannot be fundamentally different from the genuine material. Most methods to detect fraud rely on a thorough knowledge of the natural variation of characteristic constituents of the commodity concerned and make use of complex statistical procedures to derive indicators of adulteration. A range of analytical methods to detect fraud has to be developed, modified, and reappraised on a continuous basis to be a step ahead of those pursuing these illegal activities. In this article the technical merit of different analytical platforms to establish the authenticity of oils and fats is reviewed.
Effects of elevated O3, alone and in combination with elevated CO2, on tree leaf chemistry and insect herbivore performance: a meta‐analysis

We reviewed the effects of elevated ozone (O3), alone and in combination with elevated carbon dioxide (CO2) on primary and secondary metabolites of trees and performance of insect herbivores by means of meta‐analysis. Our database consisted of 63 studies conducted on 22 species of trees and published between 1990 and 2005. Ozone alone had no overall effect on concentrations of carbohydrates or nutrients, whereas in combination with CO2, elevated O3 reduced nutrient concentrations and increased carbohydrate concentrations. In contrast to primary metabolites, concentrations of phenolics and terpenes were significantly increased by 16% and 8%, respectively, in response to elevated O3. Effects of ozone in combination with elevated CO2 were weaker than those of ozone alone on phenolics, but stronger than those of ozone alone on terpenes. The magnitude of secondary metabolite responses depended on the type of ozone exposure facility and increased in the following order: indoor growth chamber
High‐Tg Carbazole Derivatives as Blue‐Emitting Hole‐Transporting Materials for Electroluminescent Devices

A series of dicarbazolyl derivatives bridged by various aromatic spacers and decorated with peripheral diarylamines were synthesized using Ullmann and Pd‐catalyzed C–N coupling procedures. These derivatives emit blue light in solution. In general, they possess high glass‐transition temperatures (Tg > 125 °C) which vary with the bridging segment and methyl substitution on the peripheral amine. Double‐layer organic light‐emitting devices were successfully fabricated using these molecules as hole‐transporting and emitting materials. Devices of the configuration ITO/HTL/TPBI/Mg:Ag (ITO: indium tin oxide; HTL: hole‐transporting layer; TPBI: 1,3,5‐tris(N‐phenylbenzimidazol‐2‐yl)benzene) display blue emission from the HTL layer. The EL spectra of these devices appear slightly distorted due to the exciplex formation at the interfaces. However, for the devices of the configuration ITO/HTL/Alq3/Mg:Ag (Alq3 = tris(8‐hydroxyquinoline)aluminum) a bright green light from the Alq3 layer was observed. This clearly demonstrates the facile hole‐transporting property of the materials described here.
Bacteria-Modified Red Mud for Adsorption of Cadmium Ions from Aqueous Solutions

Cadmium is a toxic metal widely used in industry and it enters the environment from electroplating, smelting, alloy manufacturing, pigments, plastics, cadmium-nickel batteries, fertilizers, pesticides, mining, pigments and dyes, textile operations, and refining industries. Considering the harmful effects of cadmium, it is necessary to remove cadmium from liquid wastes at least to the limit accepted by regulations. The present study describes removal of cadmium from aqueous solutions using bacteria-modified red mud waste material. Batch adsorption experiments have been performed as a function of pH, contact time, temperature, and adsorbent dosage. The optimum results were obtained at pH 4.0, contact time of 60 min, temperature of 30oC, and an adsorbent dose of 1 mg/mL. The adsorption data was correlated with Langmuir and Freundlich adsorption models. The maximum adsorption capacity obtained from Langmuir adsorption model was 83.034 mg/g. The kinetic processes of cadmium adsorption on bacteria-modified red mud were described by applying pseudo-first-order and pseudo-second-order rate equations. The kinetic data for the adsorption process obeyed pseudo-second-order rate equations. Various thermodynamic parameters, such as ΔG°, ΔH°, and ΔS° were calculated and the negative value of ΔG° obtained indicate that the process was spontaneous, and the positive value of ΔH° confirms the reaction to be endothermic, and the positive value of ΔS° shows that the decrease in the degree of freedom of the adsorbed species. The bacteria-modified red mud investigated in this study exhibited a high potential for the removal of cadmium from aqueous solutions.
Development of Solid Phase Extraction Mini-Columns for Proteome Analysis

質量分析計を用いた高感度プロテオーム解析のための試料前処理用固相抽出ミニカラムstop-and-go-extraction tip（StageTip）を開発した．StageTipは微量ペプチド試料の脱塩濃縮だけではなく，様々な種類のカラム担体，充填剤を組み合わせることにより，前分画デバイスとして，また，リン酸化ペプチドの選択的濃縮デバイスとしても用いることが可能であった．更に，試料調製過程で混入が避けられないゲル片のろ過，染色色素やイオン性界面活性剤の除去ツールとしても用いることができ，試料の保存デバイスとしても有効であった．StageTipは安価で使い捨て可能であり，特別な大型装置なしで簡便に操作ができることから，プロテオーム解析の前処理システムとして幅広い用途での使用が期待できる．
Preparation of a sugar catalyst and its use for highly efficient production of biodiesel

Novel solid acid catalysts for esterification have recently been described that are made by incomplete carbonization of carbohydrates followed by sulfonation. Herein, such a ‘sugar catalyst’ is prepared from D-glucose and its catalytic properties and structure are investigated in detail. This type of sugar catalyst is, for the first time, applied for the effective production of biodiesel from waste oils. Our results indicate that sugar catalysts are highly effective, minimally polluting and re-usable catalysts that are highly suited to the production of biodiesel from waste oils with a high acid value.
Study of Asphaltene Precipitation Using Refractive Index Measurement

Abstract The measurements of the refractive index of crude oils were utilized in this work to enhance the understanding of the behavior of asphaltenes in crude oil, specifically, their tendency to precipitate from crude oil. The onset of asphaltene precipitation was measured in eight crude oil samples, which were titrated with either heptane or pentane in order to induce precipitation of the asphaltenes. The refractive index of each sample was measured to find its relationship to asphaltene precipitation. The assumption that refractive index of a mixture is a linear combination of the refractive indexes of the individual components was verified. It was also found that mixtures of heptane or pentane and crude oil also followed this same behavior. However, as asphaltenes began to precipitate from the solution, the refractive index no longer followed this linear mixing rule. Careful analysis of the refractive index data for each of the crude oil samples revealed many interesting relationships between the refractive index data and the content of the different polar asphaltene fractions present. The refractive index of asphaltenes was predicted from the refractive index data of crude oils. The results suggest the possibility predicting the properties and characteristics of the asphaltenes contained in a crude oil simply by measuring the refractive index.
Carbon-coated α-Fe2O3 nanostructures for efficient anode of Li-ion battery

Carbon-coated α-Fe2O3 nanostructures, as the anode of Li-ion battery, have been deposited on the stainless steel substrate by a facile pyrolysis of ferrocene. The anode shows a high reversible capacity of 1138 mA h g−1 after 300 cycles at the current density of 500 mA g−1 and maintains a good capacity of 458.8 mA h g−1 even when cycled at the high current density of 10000 mA g−1. This high capacity can be associated to the nanostructure and the carbon layer coated on hematite. Moreover, the mechanism for the capacity evolution with cycling has been investigated by scanning transmission X-ray microscopy (STXM). The results reveal that the detailed composition and electronic structure change in the cycling process. Fe chemical state plays a critical role in the capacity evolution and a low oxidation state of Fe (such as Fe2+) might reduce the capacity by trapping Li+ ions, and the recovery of Fe2+ to hematite (Fe3+) significantly enhances the capacity. Data also show the growth and inhomogeneous distribution of a solid electrolyte interphase (SEI) layer containing carbon-based film, Li2O and Li2CO3. The facile synthesis of carbon-coated α-Fe2O3 opens an efficient way for large-scale anode production of Li-ion batteries, and the STXM study provides new insights into the mechanism of hematite-based Li-ion battery.
Degradation of phenol by novel strain Pseudomonas aeruginosa MTCC 4997 isolated from petrochemical industrial effluent

A strain of Pseudomonas aeuriginosa MTCC 4997 isolated newly from effluents collected from petrochemical industries. The isolated strain was optimized for various operational and environmental conditions in batch culture. This strain was utilizes phenol as a sole source of carbon and energy, capable of degrading phenol up to 1400 mg l -1 concentration within 144 h. Complete degradation was observed at wide temperature from 15 0 C to 45 0 C with an optimum of 37 0 C and pH 6.0 to 10.5 with an optimum of 7.0 to 7.5. Metals such as Fe, Cd, Cu, Pb, Zn, Mn and Ba at lower concentrations were found stimulated and enhanced the rate of phenol degradation. Therefore, the phenol degradability of the strain can be maintained and used at large scale treatment.
Reducing nitrogen losses during simulated composting of poultry manure using adsorbents or chemical amendments

Ammonia emissions during composting of poultry manure can be significant, representing increased environmental pollution and decreased fertilizer value of manure. The objectives of this study were to measure NH 3 volatilization losses during composting of poultry layer manure, and to evaluate the potential of different amendments to reduce NH 3 losses using a laboratory composting simulator. The poultry manure was treated with various amendments which included two natural zeolites, clay, coir (mesocarp of coconut fruit), CaCl 2 , CaSO 4 , MgCl 2 , MgSO 4 , and Al 2 (SO 4 ) 3 . The manure was composted for 49 to 56 d. Ammonia volatilized from the manure was trapped in a 0.3 M H 2 SO 4 solution. The composts were weighed and analyzed for moisture content, total N and NH 4 + . The NH 3 volatilization loss for the unamended manures ranged from 47 to 62% of the total manure N. A layer of 38% zeolite placed on the surface of the manure reduced NH 3 losses by 44%, whereas 33% coir placed on the surface of the manure reduced NH 3 losses by 49%. The 20% alum treatment reduced NH 3 losses by 28%. Composting poultry manure with zeolites, coir, and alum produced composts with high NH 4 + concentrations ranging from 17 to 53% of total N. The addition of 20% CaCl 2 to poultry manure decreased NH 3 volatilization but did not result in increased NH 4 + or NO 3 - concentrations. The 38% zeolite Z1 and 33% coir-treated composts had total N concentrations of 17 and 31 g kg -1 , respectively. The zeolite and coir amendments were proposed to be the most suitable for reducing NH 3 losses during composting of poultry manure.
Mitigation of nitrous oxide emissions in spray‐irrigated grazed grassland by treating the soil with dicyandiamide, a nitrification inhibitor

Abstract. Nitrous oxide (N2O) from animal excreta in grazed pasture systems makes up a significant component (c. 10%) of New Zealand's total greenhouse gas inventory. We report an effective method to decrease N2O emissions from animal urine patches by treating the soil with the nitrification inhibitor dicyandiamide (DCD), in a simulated grazed dairy pasture system under spray irrigation. The soil was a free‐draining Lismore stony silt loam (Udic Haplustept loamy skeletal) and the pasture was a mixture of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens). By treating the soil with DCD, N2O emissions were decreased by 76% following urine application in the autumn, from 26.7 kg N2O‐N ha−1 without DCD to an average of 6.4 kg N2O‐N ha−1 with DCD over the 6‐month experimental period. N2O flux was decreased by 78% following urine application in the spring, from 18 kg N2O‐N ha−1 without DCD to 3.9 kg N2O‐N ha−1 with the application of DCD over the 3‐month period. A single application of DCD immediately after urine was sufficient to effectively mitigate N2O emissions from the urine. The results showed that repeated applications of DCD after urine application, or mixing DCD with urine, offered no advantage over a single application of DCD immediately after urine deposition.
Nanopore wall effect on surface tension of methane

Local pressure is known to be anisotropic across the interfaces separating fluids in equilibrium. Tangential pressure profiles show characteristic negative peaks as a result of surface tension forces parallel to the interface. Nearby attractive forces parallel to the interface are larger than the repulsive forces and, hence, constitute the surface tension. In this work, using molecular dynamics simulations of methane inside nano-scale pores, we show this surface tension behaviour could be significantly influenced by confinement effects. The layering structure, characterised by damped oscillations in local liquid density and tangential pressures, extends deep into the pore and can be a few nanometers thick. The surface tension is measured numerically using local pressures across the interface. Results show that the tension is smaller under confinement and becomes a variable in small pores, mainly controlled by the thickness of the liquid density layering (or liquid saturation) and the pore width. If the liquid saturation inside the pore is high enough, the vapour–liquid interface is not interfered by the pore wall and the surface tension remains the same as the bulk values. The results are important for understanding phase change and multi-phase transport phenomena in nanoporous materials.
Photochromic polymer composites for two-photon 3D optical data storage

In this paper we demonstrate 3D two-photon recording and two-photon readout in photochromic polymer composites containing a mixture of 1,2-bis(2-methylbenzo[b]thiophen-3-yl)hexafluorocyclopentene (diarylethene 1) and fluorene derivatives 2,2‘-(9,9-didecyl-9H-fluorene-2,7-diyl)bis(ethene-2,1-diyl)bis(4,1-phenylene)) dibenzo[d]thiazole (2) or poly(9,9-didecyl-2,7-dipheylaminofluorene) (3). The recording mechanism in this system is based on two-photon excitation of the closed form of diarylethene 1 at 800 nm. The readout mechanism is based on the modulation of the emission intensity of fluorene derivatives 2 or 3 by the closed form of diarylethene 1 through Resonance Energy Transfer (RET). Foster distances (R0) and critical concentrations (A0) were calculated from the spectral overlap of the donor's emission (fluorene derivatives) and the acceptor's absorption (closed form of diarylethene 1) in solution and in polymer films of PMMA-co-VBP. This system was demonstrated to be suitable for recording data by two.
2,5-Dichloro-3,6-dihydroxybenzo-1,4-quinone: identification of a new organochlorine compound in kraft mill bleachery effluents

2,5-Dichloro-3,6-dihydroxybenzo-1,4-quinone (chloranilic acid) and the corresponding hydroquinone have been identified in C/D-stage and E-stage bleachery effluents from kraft pulp production using both softwoods and hardwoods. The concentrations of the quinone in these effluents were comparable to those of established individual major chlorophenolic components such as chloroguaiacols and chlorocatechols
Chemical processing of biogenic hydrocarbons within and above a temperate deciduous forest

A one-dimensional canopy model was developed to study photochemical processes inside and above a mixed deciduous forest in southern Ontario. The Eulerian model made use of Lagrangian dispersion principles with a correction factor to incorporate the average ensemble time since emission to calculate atmospheric mixing; traditional diffusion methods were found to provide insufficient mixing to match the measurements. Neglecting chemical losses while making isoprene emission estimates was found to underestimate emission rates up to 40%. The ozone oxidation of biogenic and anthropogenic alkenes was found to be a potential source of hydroxyl (OH) and hydroperoxy (HO2) radicals during the morning and night. Reactions of HO2 with organic peroxy radicals formed by the OH oxidation of isoprene during the day were shown to be a significant source of organic peroxide formation above the canopy. The primary pathways of methacrolein and methylvinylketone formation were shown to be ozone oxidation of isoprene and hydroxyl radical oxidation of isoprene, respectively. Local ozone formation was shown to be limited by low mixing ratios of nitrogen oxides, despite high levels of isoprene present at the site.
New applications of van der Waals radii in chemistry

This review is part of a continuing study of the many applications of van der Waals radii (WR) in various fields of chemistry, and especially in crystal chemistry and stereochemistry. An analysis of relevant publications has shown that WR systems are used most often and most successfully in studies of the conformation of molecules, though their original source is usually an analysis of intermolecular contacts. This review will deal with traditional applications of WR and with some some new aspects, inducing the geometrical modelling of chemical reactions and new types of specific intermolecular interactions. The bibliography includes 149 references.
Couette flow through a porous medium of a high prandtl number fluid with temperature‐dependent viscosity

The velocity and temperature profiles for an impulsively started Couette flow have been derived for a fluid with a high and strongly temperature-dependent viscosity when the flow takes place through a porous medium. The steady as well as the transient state flows are discussed and the influence of the medium permeability is assessed. In the steady state the presence of the porous medium causes higher maximum temperatures only for sufficiently low permeabilities and in all cases significantly lower velocity profiles. The flow development times tend to be higher for the low permeabilities only for high Nahme numbers. For the transient state it is noticeable that, in all cases, the velocity develops much more rapidly than the temperature and that the presence of the porous medium accelerates this tendency. Finally the medium permeability produces skew temperature profiles and higher temperature time gradients at all times.