Miracle-dz/UniFAR-FTUs huggingface dataset:
Field study on colloid transport using fluorescent microspheres

Understanding colloid movement through the vadose zone is important, because colloids may facilitate transport of some less mobile contaminants. Experimental evidence of colloid transport in the vadose zone, especially at the field scale, is rare. We developed and tested a method to detect and quantify local concentrations of fluorescent microspheres (MS) with a diameter of 1 μm in unsaturated soil based on fluorescent microscopy. The detection limit was 400 × 106 MS kg−1 field‐moist soil for an automated counting method, and 20 × 103 MS kg−1 for manual counting. To test the method in the field, we applied a 40‐mm pulse with an input concentration of 14.6 × 109 MS litre−1 on two plots during 6 hours, together with bromide (Br−) and the food dye Brilliant Blue (BB). The concentrations of MS were determined on horizontal cross‐sections by a randomly distributed sampling scheme, either directly after application or 90 days after application and a rainfall of 100 mm. Mass recoveries for the MS of 85 and 65% were acceptable in view of the field conditions. Even after infiltration of particle‐free water, the largest MS concentrations were measured at the soil’s surface, which pointed at physical retention mechanisms. An additional selective sampling of hydrologically active preferential flow pathways, guided by the dye infiltration patterns, revealed that the MS were transported to similar depths as BB, that is 0.80 m directly after irrigation and 1.7 m after 90 days. This implies that also a small fraction of the particulate tracers was rapidly transported to larger depths, regardless of their physico‐chemical properties.
Comparative Study of Selected Soil Properties Following Introduction of Broad‐Leaf Trees into Clear‐Felled Chinese Fir Forest

Abstract After clear‐cutting of the first generation Chinese fir (Cunninghamia lanceolata) planted forest, five management models, viz. mixture of Chinese fir and Kalopanax septemlobus (MCK), mixture of Chinese fir and Alnus cremastogyne (MCA), pure Kalopanax septemlobus stand (PKS), pure Alnus cremastogyne stand (PAS), and pure Chinese fir stand (PCS), were established in 1983. The effects of these management models on soil were evaluated by measuring physico‐chemical parameters and soil solution chemistry 20 years after planting. Both broadleaf monocultures and mixtures of broadleaf and conifer exerted a favorable effect on soil fertility. The concentrations of the mainly atmospherically derived ions, including SO4 2−, Cl−, Na+, and Mg2+, were significantly higher under conifer than under broadleafs and under mixtures of broadleaf and conifer. Whereas the concentrations of ions that were mainly controlled within system processes such as K+ and NH4 + varied little among various management models, with the exception of NO3 −, which was significantly higher below PAS than below the others. The concentrations of H+ and Al3+ were also highest under the conifer. In addition, the aerosol sulfate and SO2 deposition did not result in a net loss of base cations (on an area basis) from the broadleaf monocultures and mixtures of broadleaf and conifer. However, slight decreases in forest floor bases were observed under the conifer. The observed evidence from this study also suggests that the principal factor for forest soil acidification may be the N deposition and nitrification of NH4 +, but not S deposition in this region.
Variability of Stockton Coal Mine drainage chemistry and its treatment potential with biogeochemical reactors

Abstract Thirteen acid mine drainage seeps emanating from waste rock dumps and associated sediment ponds were monitored at Stockton Coal Mine near Westport, New Zealand to identify and quantify metal loads and delineate their spatial and temporal variability. Dissolved metal concentrations ranged from 0.05–1430 mg/L Fe, 0.200–627 mg/L Al, 0.0024–0.594 mg/L Cu, 0.0052–4.21 mg/L Ni, 0.019–18.8 mg/L Zn, <0.00005–0.0232 mg/L Cd, 0.0007–0.0028 mg/L Pb, <0.001–0.154 mg/L As and 0.103–29.3 mg/L Mn and the pH ranged from 2.04–4.31. Currently this acid mine drainage is treated further downstream by a number of water treatment plants employing a combination of ultra fine limestone and Ca(OH)2. However, in the interest of assessing more cost-effective technologies, biogeochemical reactors were assessed in the laboratory as potential cost-effective passive treatment options. Results of mesocosm-scale treatability tests showed that biogeochemical reactors incorporating mussel shells, pine bark, wood fragments (post peel) and compost increased pH to >6.7 and sequestered ≥98.2% of the metal load from the Manchester Seep located within the Mangatini Catchment. Laboratory results demonstrated that the maximum loading rate was 0.8 mol total metals/m3 substrate, and an average of 20.0 kg/day (7.30 tonnes/year) of metals could be removed by appropriately sized biogeochemical reactors.
Functionalization and characterization of pyrolyzed polymer based carbon microstructures for bionanoelectronics platforms

In this study, the investigation of surface-treatment of chemically inert graphitic carbon microelectrodes (derived from pyrolyzed photoresist polymer) for improving their attachment chemistry with DNA molecular wires and ropes as part of a bionanoelectronics platform is reported. Polymer microelectrodes were fabricated on a silicon wafer using standard negative lithography procedures with negative-tone photoresist. These microelectrode structures were then pyrolyzed and converted to a form of conductive carbon that is referred to as PP (pyrolyzed polymer) carbon throughout this paper. Functionalization of the resulting pyrolyzed structures was done using nitric, sulfuric, 4-amino benzoic acids (4-ABA), and oxygen plasma etching and the surface modifications confirmed with Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and electron dispersion x-ray spectroscopy (EDS). Post surface-treatment analysis of microelectrodes with FTIR and Raman spectroscopy showed signature peaks characteristics of carboxyl functional groups while EDS showed an increase in oxygen content in the surface-treatment procedures (except 4-ABA) indicating an increase in carboxyl functional group. These functional groups form the basis for peptide bond with aminated oligonucleotides that in turn could be used as molecular wires and interconnects in a bionanoelectronics platform. Post-pyrolysis analysis using EDS showed relatively higher oxygen concentrations at the edges and location of defects compared to other locations on these microelectrodes. In addition, electrochemical impedance measurements showed metal-like behavior of PP carbon with high conductivity (|Z| <1 KΩ) and no detectable detrimental effect of oxygen plasma surface-treatment on electrical characteristic. In general, characterization results—taken together—indicated that oxygen plasma surface-treatment produced more reliable, less damaging, and consistently repeatable generation of carboxyl functional groups than diazonium salt and strong acid treatments.
Ultrabroadband Plasmonic Absorber for Terahertz Waves

Perfect absorbers that exhibit broadband absorption of terahertz radiation are promising for applications in imaging and detection due to enhanced contrast and sensitivity in this relatively untapped frequency regime. Here, terahertz plasmonics is used to demonstrate near‐unity absorption across a broad spectral range. The absorber comprises a planar array of cross‐shaped structures defined by surface etching of doped silicon. Absorbance of over 90% is observed numerically with a relative bandwidth of 90% from 0.67 to 1.78 THz, in reasonable agreement with experimental observation. This ultrabroadband absorption is attributed to two resonance modes supported by plasmonic cavities that are defined by the etched cross structure. This terahertz absorber is single‐layered, polarization‐insensitive, and exhibits consistent performance across a wide range of incidence angles. The plasmonic‐based approach for enhancing absorption is a potential precursor to the realization of efficient bolometric imaging and communications at terahertz frequencies.
TiO2 Thin Film Electrodes: Correlation between Photocatalytic Activity and Electrochemical Properties

The results of Mott−Schottky measurements on thin film TiO2 electrodes have been compared with the photocatalytic activities of these films for the photocatalytic reduction of methylviologen and the oxidation of methylene blue, respectively, under UV light irradiation. The purpose of this study was to find an alternative method to predict the photocatalytic activity of titanium dioxide thin films. While impedance measurements were carried out on FTO-glass, the activity tests were performed separately on standard glass substrates. The initial photonic efficiency of the reduction of methylviologen was found to correlate with both the flatband potential and the donor density of the investigated titanium dioxide thin film electrodes. The more negative the flatband potential the higher are both the donor density and the photonic efficiency of the photocatalytic methylviologen reduction. No such dependency was found, however, for the photonic efficiency of the methylene blue oxidation.
Wettability and Hysteresis Effects on Water Sorption in Relatively Dry Soil

The soil water retention curve (SWRC) is a key tool for understanding the fundamental relationship between soil moisture content and its associated energy. The objective of this study was to measure soil water retention including hysteresis at the dry end of the SWRC and to examine the effect of wettability on the SWRCs of two wettable soils and their hydrophobized counterparts. Two conditions, wettable and hydrophobic, were measured for each soil. The method used to measure the SWRCs was vapor equilibration over salt solutions of known osmotic potentials. Free water in the form of individual droplets was found to be present at the surface of the unwashed hydrophobic soils due to decreases in the osmotic potential during the hydrophobizing process. Water droplets did not form on the hydrophilic and washed hydrophobic soils. Soil wettability was found to affect soil water retention in relatively dry soil. The hydrophilic soils used in this study exhibited significant hysteresis in the water potential range of ―2.3 to ―19.2 MPa. Soil wettability and hysteresis should be considered when studying water sorption and desorption in relatively dry soil.
Effects of Annealing on the Nanomorphology and Performance of Poly(alkylthiophene):Fullerene Bulk‐Heterojunction Solar Cells

The evolution of nanomorphology within thin solid‐state films of poly(3‐alkylthiophene):[6,6]‐phenyl‐C61 butyric acid methyl ester (P3AT:PCBM) blends during the film formation and subsequent thermal annealing is reported. In detail, the influence of the P3AT's alkyl side chain length on the polymer/fullerene phase separation is discussed. Butyl, hexyl, octyl, decyl, and dodecyl side groups are investigated. All of the P3ATs used were regioregular. To elucidate the nanomorphology, atomic force microscopy (AFM), X‐ray diffraction, and optical spectroscopy are applied. Furthermore, photovoltaic devices of each of the different P3ATs have been constructed, characterized, and correlated with the nanostructure of the blends. It is proposed that the thermal‐annealing step, commonly applied to these P3AT:PCBM blend films, controls two main issues at the same time: a) the crystallization of P3AT and b) the phase separation and diffusion of PCBM. The results show that PCBM diffusion is the main limiting process for reaching high device performances.
DETERMINATION OF LATERAL DIFFUSION-COEFFICIENTS IN AIR WATER MONOLAYERS BY FLUORESCENCE QUENCHING MEASUREMENTS

The fluorescence quenching of a lipoidal pyrene derivative, by two amphiphilic quenchers, at the air-water interface, has been studied by steady-state and time-resolved methods. The results have been analyzed in the theoretical framework of diffusion-controlled quenching in a two-dimensional environment to yield the mutual lateral diffusion coefficients
Theoretical study of the effects of intermolecular interactions in self‐assembled long‐chain alkanes adsorbed on graphite surface

In this paper, we studied the physisorption of long‐chain alkanes CnH2n+2 (n = 8, 16, 24, 34) on a graphite surface using molecular mechanics simulations. The computed results illustrated that the interactions between adsorbed molecules and substrate are dominated by van der Waals forces whereas the electrostatic interactions are very small. It was found that the ratio of the alkane molecule–molecule interactions (two‐dimensional crystallization energy) to the interactions between alkane and graphite (adsorption energy) ranges from ∼2 : 5 to 3 : 5. The adsorption stability and immobility of the alkanes increases proportionally with an increase in the chain length. It was concluded that the lateral interactions between adsorbed molecules are important to the formation of ordered two‐dimensional lamellae. The theoretical results support the scanning tunneling microscopy (STM) observation of alkylated aromatic compounds on a graphite surface. Copyright © 2001 John Wiley & Sons, Ltd.
Room, low, and high temperature dehydration and phase transitions of kernite in vacuum and in air

Kernite Na2B4O6(OH)2·3H2O dehydration in air at high temperature and in vacuum at room temperature has been studied. It was found that kernite easily dehydrates forming a new phase‐I both on heating and in vacuum. The chemical formula Na2B4O6(OH)2·1.5H2O of the new phase‐I has been estimated on the basis of thermogravity analysis. It is triclinic with the unit cell parameters a = 7.047(8), b = 8.76(1), c = 13.08(2) Å, α = 93.40(9), β = 95.32(9), γ = 90.28(9)° changing slightly on pressure reduction. Due to the relatively low temperature (353 K) and reversibility of the kernite ⟷ phase‐I transition an anion of the new phase‐I likely consists of the same chains [B4O6(OH)2]2– like in kernite structure. The high anisotropy of kernite thermal expansion was explained by approaching of NaO chains due to the initial removing of water molecules from kernite crystal structure. The behaviour of the new phase‐I at low temperatures in vacuum was also investigated. A formation of an additional new phase II has been detected at the temperature of 93 K. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Free Convection Heat and Mass Transfer MHD Flow in a Vertical Porous Channel in the Presence of Chemical Reaction

The objective of the present study is to examine the fully developed free convective MHD flow of an electrically conducting viscous incompressible fluid in a vertical porous channel under influence of asymmetric wall temperature and concentration in the presence of chemical reaction. The heat and mass transfer coupled with diffusion-thermo effect renders the present analysis interesting and curious. The analytical solution by Laplace transform technique of partial differential equations is used to obtain the expressions for the velocity, temperature, and concentration. It is observed that under the influence of dominating mass diffusivity over thermal diffusivity with stronger Lorentz force the velocity is reduced at all points Further, low rate of thermal diffusion delays the attainment of free stream state. Flow of aqueous solution in the presence of heavier species is prone to back flow.
Relationship between Physical Dough Properties and the Improvement of Bread-Making Quality during Flour Aging

The relationship between physical dough properties and bread-making quality during flour aging was investigated for two Japanese domestic bread-making spring wheat cultivars (Haruyutaka, Haruyokoi) and the winter wheat cultivar (Kitanokaori). The specific loaf volume increased for 4 weeks after milling in all cultivars. The decrease in the breaking deformation of dough continued for 8 weeks in all cultivars and showed a higher negative correlation coefficient to the specific loaf volume. In addition, a greater increase of specific loaf volume was observed by decreasing the breaking deformation in a cultivar with less breaking deformation immediately after milling. Farinograph stability increased for 2 weeks after milling and also showed higher correlation coefficients to specific loaf volume. Water absorption showed higher correlation coefficients to the breaking deformation in Haruyutaka and Haruyokoi but a negative correlation in Kitanokaori. The breaking force, gassing power, and vacuum expansion volume of dough showed lower correlation coefficients to the specific loaf volume in all cultivars. Overall, a higher correlation coefficient was observed among breaking deformation decrease, farinograph stability, and specific loaf volume during flour storage. The relationship between the breaking deformation immediately after milling and the increasing rate of specific loaf volume would be a useful indicator of flour aging maturity.
Composition of Turkish Bitter Orange and Lemon Leaf Oils

Abstract Bitter orange (Citrus aurantium L.) and lemon (Citrus limon (L.) Burm. f. ) leaf oils were obtained from bitter orange tree leaves and lemon tree leaves by steam distillation. The oils were analyzed by high-resolution gas chromatography (HRGC) and high-resolution gas chromatography mass spectrometry (HRGC/MS). In total, 50 and 60 components have been identified in bitter orange and lemon leaf oils, respectively. Bitter orange leaf oil showed a high content of oxygenated compounds (89.6%) with linalyl acetate (50.1%) and linalool (24.8%) being the main components. Lemon leaf oil was characterized by higher content of monoterpene hydrocarbons (64.2%) of which limonene (44.2%) and β-pinene (10.6%) were the major components. It contained a lower content oxygenated compounds (33.5%) than the bitter orange leaf oil.
Ordered binary monolayer composed of two organic molecules: Copper-phthalocyanine and 3,4,9,10-perylene-tetra-carboxylic-dianhydride on Cu(111)

The two planar organic molecules copper-phthalocyanine (CuPc) and 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) are found to form an ordered mixed monolayer on Cu(111). The layers have been prepared by exposing the surface to an equivalent of a little bit more than half of a monolayer of CuPc and the same amount of PTCDA followed by thermal annealing. The investigations by scanning tunneling microscopy reveal regular patterns with a commensurate unit cell which contains one CuPc and two PTCDA molecules.
Understanding and Improving Solid-State Polymer/C60-Fullerene Bulk-Heterojunction Solar Cells Using Ternary Porphyrin Blends

Solid-state heterojunction solar cells formed from binary blends of conjugated polymers and fullerenes provide a promising class of organic devices. We demonstrate that ternary blends incorporating porphyrins can be of similar morphology to the binary mixture and retain full device functionality. They allow, for the first time, the construction of efficient devices containing less than 10% polymer. By analyzing the absorption spectra as a function of concentration, we determine the proportion of light absorbed by each individual component in both binary and ternary mixtures. This analysis reveals that the majority of the light is absorbed by the fullerene in 1:4 polymer/C60-fullerene blends, with over 50% of the photocurrent produced under AM 1.5 conditions occurring subsequent to C60-fullerene absorption. This result provides for a consistent understanding of the origin of primary charge separation in general polymer/C60-fullerene blends, polymer/C70-fullerene blends, and polymer-fullerene dyad molecules.
Correlations between Rheological and Optical Properties of a Micellar Solution under Shear Banding Flow

We report on the nonlinear rheological and optical responses of a micellar viscoelastic solution of 0.3 M cetyltrimethylammonium bromide in water with a mineral salt, 1.79 M sodium nitrate , subjected to different steplike shear rates. This solution, which can be described in the regime of small deformations by the Maxwell model with a single relaxation time (τR), shows a stress plateau in the experimental flow curve (σ(γ)) beyond a critical shear rate γc1. This behavior, characteristic of a system undergoing a phase transition of the shear banding type, is corroborated by steady-state flow birefringence experiments. The transient shear stress profiles (σ(t)) recorded after the startup of flow are very similar to those previously published on the cetylpyridinium chloride/sodium salycilate system. Just after the inception of the flow, σ quickly increases with time and then relaxes toward its stationary value. This relaxation mechanism occurs on two different time scales and has been interpreted as follows.
Experimental Investigation on the Translational and Rotational Motion of Biomass Particle in a Spout-Fluid Bed

Abstract The translational and rotational motions of biomass particle in a spout-fluid bed have been investigated. Two kinds of cylindrical biomass particles with different densities were used as bed solids, which were obtained from the jujube tree. To describe the translational and rotational characteristics, virtual particle concentration and rotation angle were introduced. The former obtained by microwave heating-infrared thermal imaging technique was compared with the actual particle concentration determined by box-counting method. Based on the temperature distribution, the translational position and rotation angle of multiple tracers were distinguished. The results show that the heating characteristic of tracer depends on the tracer material. Compared to the spherical particles, non-spherical biomass particle is more likely to cause dead zone in the bed. In the flow regime of fluidizing, the flow characteristic of biomass particle relies on the jet gas velocity. The high resistance resulting from the interparticle cohesion forces hinders the rise of bubbles and weakens the radial dispersion of particle. In the fountain, homogeneous biomass particle rotates uniformly, while non-homogeneous biomass particle exhibits non-uniform rotation. In the annulus, the rotation characteristic of biomass particle depends on the structure of fountain and particle trajectory in the annulus.
Di- und trimeres Dimethylaminoisocyanat. Strukturen und Spektren / Di- and Trimeric Dimethylaminoisocyanate. Structures and Spectra

Abstract N-Heterocyclic Compounds N,N-Dimethyl-N′,N′-bis(trimethylsilyl)hydrazine reacts with fluorophosgene to yield 5,5-dimethyl-3-dimethylamino-2,4-dioxo-5-azonia-imidazolidide (1). With phosgene, 1-methyl-2-chloroformyl-4-dimethylamino-1,2,4-triazolidine-3,5-dione (5) can be prepared. The thermal decomposition of N,N-dimethyl-N'-carbomethoxi-N′-trimethylsüyl-hydra-zine gives 1,3,5-tris(dimethylamino)-1,3,5-hexahydrotriazine-2,4,6-trione (2) and 1,2-dimethyl-4-dimethylamino-1,2,4-triazolidine-3,5-dione (3). 2 can also be prepared by thermal decomposition of N.N-dimethyl-N′-carbomethoxi-N′-fluoroformylhydrazine (4). The crystal and molecular structures of 1 and 2 were determined by X-ray analysis. The 1H NMR and vibrational data of 1-5 were communicated. The mass spectra of 1-3 were measured and discussed.