Miracle-dz/UniFAR-FTUs huggingface dataset:
Effects of Ice Melting on Cu, Cd and Pb Profiles in Ross Sea Waters (Antarctica)

Abstract In the framework of the Italian Research Programme in Antarctica, evolution of dissolved and particulate Cu, Cd and Pb profiles in the coastal waters of Gerlache Inlet (Terra Nova Bay, Western Ross Sea) was studied during the Austral Summer 1997/98. In order to relate the distributions of trace metals with the physical and biological processes, a series of temperature and salinity measures were made, and water samples were collected to determine nutrients and chlorophyll. Samples of pack ice and marine microlayer (50–150 μm) were also collected and analysed. Concerning the surface layer, it was found that metal concentrations are mainly affected by the dynamic of the pack ice melting and phytoplankton activity. The first process influences both the input of metals from meltwaters and the covering of the seawater surface, allowing atmospheric dust input only when all ice has been melt or removed. Direct release of particulate Cu from ice was clearly shown by surface maxima and by the high concentrations of suspended particulate matter and particulate metals found in the ice core section interfaced with the seawater. Differently, the high amount of Cd in the particulate included in the pack ice seems not to affect the concentration in surface particulate; on the contrary, the corresponding increase of dissolved Cd indicates that it isreleased in dissolved form when the pack ice melts. Surface distribution is further complicated by the effect of phytoplankton activity, which removes Cu and Cd from water, incorporating them into organic particulate. Finally, in absence of pack ice, there is evidence of inputs of Pb and Cu due to atmospheric dust brought into the column water through marine microlayer. In intermediate and deep waters, the vertical distribution of Pb and Cd was characterised by substantially constant profiles, while Cu shown, during the end of the summer and in absence of a well-defined water column stratification, a “scavenging-type” distribution which overlaps its “nutrient-type” behaviour.
SOIL RESPIRATION IN A MIXED GRASSLAND ECOSYSTEM

Soil respiration was measured in a mixed grassland ecosystem in southwestern Saskatchewan during 1970–72, using an infrared gas-analysis system. The site, on heavy-clay soil, was dominated by Agropyron dasystachyum and A. smithii. Soil respiration reached peak values (about 200 mg m−2h−1) during late June or early July. Rates earlier and later were limited primarily by low temperatures and soil water stress. A multiple regression analysis revealed that up to 74% of the variation in soil respiration could be explained by the variables: soil temperature, soil moisture and precipitation. The strong influence of precipitation suggests that wetting of the litter layer and dead vegetation might exert an important control over decomposition in this grassland.
Kinetic model for short‐cycle bulk styrene polymerization through bifunctional initiators

A model describing the kinetics of bulk styrene polymerization through bifunctional initiators has been developed. The diffusion-controlled propagation and termination reactions at high monomer conversions are modeled with the free volume theory for polymer solutions. Three different commercially available bifunctional initiators were experimentally evaluated for a wide range of polymerization conditions to study the effect of the reaction rate on the molecular weight and molecular weight distribution. The model predictions for the same polymerization conditions show excellent agreement with the experimental data, for the whole range of conversions, for both reaction rate and molecular weight distribution development, under all the conditions tested. It is demonstrated throughout this study that high molecular weights, very high reaction rates, and narrow molecular weight distributions can be achieved simultaneously by using bifunctional initiators. A comparison between monofunctionally initiated systems with the bifunctionally initiated ones shows that short-cycle reactions with reductions in polymerization time of up to 75% may be achieved with the bifunctional initiators for a wider range of conditions without significantly affecting the molecular weight and molecular weight distribution of the final product.
Who Gets the Ventilator? Moral Decision Making Regarding Medical Resource Allocation in a Pandemic

As the COVID-19 pandemic increases the number of critically ill patients flowing into hospitals, hospitals in many countries are facing a growing shortage of vital equipment and supplies, presenting ethical dilemmas to physicians who have to decide which COVID-19 patients to prioritize when resources are scarce. Using over 75,000 hypothetical decisions collected from over 5,000 people across 11 countries accounting for over 69% of all COVID-19 cases reported worldwide, we explore lay people’s preferences of how scarce medical resources should be allocated in the time of the COVID-19 pandemic. We first examine the global ethical preferences in medical resource allocation decisions as well as cross-country differences. We then document individual variations in these preferences. Our findings suggest that people have the strongest preferences for saving young (vs. old) patients and saving patients that are more likely to survive, indicating that lay people consider maximizing total benefits as the most important ethical rule when allocating scarce medical resources in the COVID-19 pandemic. Country-level differences in cultural dimensions (e.g., individualism-collectivism) and economic development (e.g., GDP per capita) contribute to cross-country differences in weights attached to various patient characteristics. Individual characteristics (e.g., gender, age, religiosity) and the severity of the local pandemic also have an impact on people’s ethical preferences.
ACOUSTIC NEARFIELD CHARACTERISTICS OF A WRINKLED PREMIXED FLAME

Nearly all combustion systems are prone to exhibit self-excited oscillations. These oscillations are driven by means of acoustic interactions between the flame and it's acoustic near-field. This acoustic nearfield is sensitive to the shape of the flame surface. This paper analyzes the near-field acoustic characteristics of premixed wrinkled, flame fronts subjected to acoustic excitation. The flame thickness is assumed to be very small compared to the length scale of the acoustic oscillations. The values of acoustic pressure and velocity on the wrinkled flame surface are transferred to a mean reference surface by means of a Taylor's expansion. A Boundary Integral Equation describing the expectation value of the coherent acoustic pressure field in the domain of interest is derived. The flame surface wrinkling is modeled by a Weierstrass-Mandelbrot fractal function. Numerical results for 2-D dump and rod stabilized flame configurations using the Boundary Element Method (BEM) are presented. The acoustic pressure field is seen to be highly two-dimensional in the case of the wrinkled flame. The difference between the acoustic pressure on the flame surface and the wall is shown to be significant in the case of a wrinkled flame subjected to acoustic excitation from downstream for the case of the dump stabilized flame. The same is observed under upstream excitation in the case of the rod stabilized flame. The normalized flame surface acoustic impedance is found to vary monotonically from the base of the flame to the tip of the flame in the case of smooth flames (i.e., flame front with no wrinkling). The wrinkled flame however, is seen to have a nearly constant impedance variation along its surface.
A Series of Lanthanide Frameworks with a Flexible Ligand, N,N′-Diacetic Acid Imidazolium, in Different Coordination Modes

{[La(trans-DAM)(cis-DAM)(H2O)2](ClO4)·3H2O}n (1), {[La2(trans-DAM)3(H2O)6](OH)3·7H2O}n (2), {[La(trans-DAM)2(H2O)2]Cl·4H2O}n (3), {[Nd(trans-DAM)2(H2O)2]X·3H2O}n (X = ClO4 (4), NO3 (5)), {[Nd(trans-DAM)(cis-DAM)(H2O)2]Cl·5H2O}n (6), and {[Nd(trans-DAM)2(H2O)2]Cl·5H2O}n (7) incorporating a flexible ligand HDAM (N,N′-diacetic acid imidazolium) were prepared in H2O or H2O/DMF (N,N′-dimethylformamide) solvents. Compounds 1 and 2 both contain the same 2D corrugated layers bridged by DAM− with different bridging modes to form different 3D structures, exhibiting tcs and (4,6)-connected topologies, respectively. The structural differences of 1 and 2 lie in the linkages of DAM− between the layers. Compound 3 also possesses a 3D architecture with an ant net, which is pillared by 2D (4,4) fan-shaped layers in an −ABAB− sequence. Compounds 4−6 contain similar 2D layers to 1 and 2. The analogous cationic structures 4 and 5 show a 4-connected sql net and 6 presents a (4,5)-connected network, resulting from the differen.
Uptake of HCl molecules by aqueous sulfuric acid droplets as a function of acid concentration

The uptake of HCl molecules by aqueous sulfuric acid droplets was measured at 283 K as a function of acid mole fraction. In the apparatus a controllable stream of monodispersed droplets is produced by a vibrating orifice jet. The droplets enter a flow system containing HCl(g). The droplets are switched on and off while the density of the species is continuously monitored by infrared absorption. From the on-off signal a coefficient for the probability of gas uptake upon collision with the liquid surface is calculated. This coefficient is 0.15 for pure water, remains constant up to 0.1 mole fraction of H2SO4 (40 wt %) and then drops sharply to <10−2 at 0.2 mole fraction (60 wt %). The results are in accord with calculations based on the decrease in the solubility of HCl with increasing H2SO4 mole fraction. Increasing acidity reduces the dissociation of HCl into H+ and Cl− in solution. Our results indicate that mass accommodation coefficients are large enough so that the HCl content of stratospheric aerosols will be determined entirely by this solubility.
Dielectric dispersion in pure polar liquids at very high radio-frequencies I. Measurements on water, methyl and ethyl alcohols

The results are given of some measurements of the absorption coefficient and refractive index of water, methyl and ethyl alcohols at wave-lengths of 6·2 mm, 1·24 cm and 3·21 cm over the temperature range —10 to 50°C, including some observations on water in the supercooled state. The method used is based upon the fact that the rate of attenuation of radio-frequency energy along a wave-guide filled with the liquid is dependent upon both the absorption coefficient and the refractive index when the guide is operated near to the cut-off condition. The electrical characteristics of water vary in a continuous manner through the normal freezing-point of 0°C down to at least —8°C. The measurements indicate that both alcohols, like water, have relatively high atomic polarizations.
Factors Affecting Oxidation Stability of a Deuterated Ester

The significantly higher oxidation stability obtained on deuteration of the acid moiety of a neopentyl polyol ester is the result of two effects, viz, the deuteration effect and the synergistic effect of alkali metal compounds with the antioxidant. The enhancement in oxidation stability attributable to 96 atom percent deuteration appears to be three-to-fourfold at 220°C. The enhancement due to the alkali metal effect appears to be about thirtyfold. Preliminary results indicate that at higher deuterium concentration levels (>96 atom percent), the oxidative stability of the ester, deuterated on the acid moiety, is further increased. Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Hartford, Connecticut, October 18–20, 1983
Influence of supporting electrolyte concentration and composition on formal potentials and entropies of redox couples incorporated in Nafion coatings on electrodes

Donnees theoriques confirmees par des etudes en presence de differents couples redox incorpores dans le revetement de Nafion. Cas de [Ru (NH 3 ) 5 Cl] Cl 2 et [Os (bpy) 3 ] I 2 , (avec bpy=bipyridine-2,2'), en particulier
DOUGLAS-FIR SEEDLING RESPONSE TO A RANGE OF AMMONIUM: NITRATE RATIOS IN AEROPONIC CULTURE

The objective of the experiment was to identify the most favorable nitrogen (N) source ratio of ammonium (NH4 +) and nitrate (NO3 −) for aeroponically-grown Douglas-fir when pH was maintained at pH 4.0. Seedlings were grown in controlled environments with solutions containing 0:100, 20:80, 40:60, 60:40, 80:20 or 100:0 NH4 +:NO3 − ratios. Nutrient additions in the aeroponic culture units were controlled by solution conductivity set points. Seedling growth and nutrient allocation was observed for 45 days. Different NH4 +:NO3 − ratios resulted in significant differences in the rate of N addition, growth, morphology, and nutrient allocation. Seedlings grown in solutions containing 60 or 80% NO3 − were characterized by a combination of high growth and photosynthetic rates, high and stable internal plant N concentrations, and sufficient levels of other essential nutrients. High proportions of NH4 + in solution resulted in low rates of N addition, stunted lateral root growth, and may have been toxic.
Effect of Particle Size on the Oil Yield and Catechin Compound Using Accelerated Solvent Extraction

Kajian ini bertujuan untuk mengkaji kesan saiz zarah ke atas pengekstrakan sebatian catechin daripada biji Areca catechu L. dengan menggunakan Pengekstrakan Pelarut Terpecut (PPT). Saiz zarah biji Areca catechu dipelbagaikan dari 75 μm sehingga 500 μm. Pengekstrakan telah dijalankan padaparameter tetap iaitu suhu (140oC), tekanan (1500 psi), masa (10 minit), isipadu semburan (60%) dan satu kitaran pengekstrakan, masing-masing. Hasil minyak peratusan yang lebih tinggi adalah 300 mg minyak / gram sampel (30.00% pati minyak) ditemui pada 125 μm. Walaubagaimanapun, kandungan catechin dalam pati minyak hanya 0.0375 mg catechin / gram sampel. Saiz zarah yang terbaik dalam julat uji kaji ini telah dikenal pasti pada 500 μm yang memberikan kandungan catechin yang tinggi iaitu 0.0515 mg catechin / gram sampel dari 247.5 mg minyak / gram sampel (24.75% pati minyak). Kata kunci: Saiz zarah; catechin; LC-MS-TOF; pengekstrakan pelarut terpecut The purpose of this work is to investigate the effects of particle size on the extraction of catechincompound from Areca catechu L. seeds by using Accelerated Solvent Extraction (ASE). The particle sizes of Areca catechu L. seeds are varied from 75 µm until 500 µm. The extraction is conducted at fixed parameters which are temperature (140oC), pressure (1500 psi), extraction time (10 minutes), flush volume (60%) and the static cycle is done for 1 extraction cycle respectively. Higher percentage oil yield of 300mg oil/gram of sample (30.00% oil yield) is found at 125 µm. However, the amount of catechin in oil yields is only 0.0375 mg of catechin/gram of sample. The best of particle size within the experimental range has been identified at 500 µm which gives a high content of catechin with 0.0515 mg Catechin/gram of sample from 247.5 mg oil/gram of sample (24.75% oil yield). Keywords: Particle size; catechin; LC-MS-TOF; accelerated solvent extraction
Identification of a New Isomer of Dihydrophaseic Acid 3'-O-β-D-Glucopyranoside from Nelumbo nucifera

-10' 0.92, s 16.5 0.92, s 16.4 1'' 4.36, d (J = 7.6 Hz) 103.3 4.34, d (J = 7.6 Hz) 103.22'' 3.13, t (J = 8.8 Hz) 75.2 3.13, t (J = 8.8 Hz) 75.13'' 3.35, m 78.2 3.36, m 78.24'' 3.26, m 71.8 3.26, m 71.85'' 3.29, m 78.1 3.27, m 78.1 6'' 3.67-3.85, m 62.9 3.64-3.85, m 62.9
Crystallization of Metastable Polymorphs of Phenobarbital by Isomorphic Seeding

Six metastable polymorphs (V, VII−XI) of phenobarbital (Pbtl) were produced by melt crystallization via seeding with corresponding isomorphic barbiturate homologues, following the teachings of earlier thermoanalytical studies of isopolymorphic relationships and utilizing the melting phase diagrams of Pbtl admixtures with various 5,5-substituted barbituric acid derivatives. The Pbtl forms and their solid solutions were analyzed with hot-stage microscopy, powder X-ray diffraction, and infrared spectroscopy. The crystal structures of several isomorphic homologues were determined to assess the structural features of the metastable Pbtl polymorphs. In contrast to Pbtl-V, VIII, and IX, which could be isolated as a single component phase, Pbtl-VII, X, and XI could only be stabilized in the presence of one of the isomorphic additives. Form Pbtl-V, the most stable form among the six metastable polymorphs, is structurally similar to Pbtl-IV and was crystallized by seeding with co-crystals of Pbtl/rutonal (3:1). Pbt.
THIN-LAYER DRYING CHARACTERISTICS AND MODELING OF CELERY LEAVES UNDERGOING MICROWAVE TREATMENT

The effect of microwave drying on moisture content, moisture ratio, drying rate, drying time, and effective moisture diffusivity of celery leaves (Apium graveolens) was investigated. By increasing the microwave output power from 180 to 900 W the drying time decreased from 34 to 8 min; by increasing the sample amount from 25 to 100 g, the drying time increased from 25 to 49 min. To determine the kinetic parameters, the drying data were fitted to various models based on the ratios of the differences between the initial and final moisture contents and equilibrium moisture content versus drying time. Among the models proposed, the semi-empirical Midilli et al. model gave a better fit for all drying conditions applied. The activation energy was calculated using an exponential expression based on the Arrhenius equation. The relationship between the drying rate constant and effective moisture diffusivity was also estimated and gave a linear relationship.
Mechanism analysis of the capacitance contributions and ultralong cycling-stability of the isomorphous MnO2@MnO2 core/shell nanostructures for supercapacitors

A facile method to synthesize isomorphous MnO2@MnO2 core/shell nanostructures was developed for the first time by using MnO2 nanowires as seed crystals. These unique nanoarchitectures consisting of an isomorphous layer of β-MnO2 nanosheets well grown on the surface of β-MnO2 nanowires exhibit remarkable electrochemical performance with high capacitance and ultra long cycle life, i.e., nearly 92.2% retention after 20 000 cycles at a current density of 5 A g−1. The enhanced specific capacitance of the MnO2@MnO2 electrode is largely contributed by the capacitive processes including double-layer charging and Faradaic pseudocapacity. Particularly, these intriguing behaviors are strongly correlated with the unique isomorphous core/shell hierarchical configuration and high mechanical stability as well as the better interfacial structures between the MnO2 nanowire core and the ultrathin MnO2 nanosheet shell. In addition, it is demonstrated that the formation of defective and disordered regions throughout the whole core/shell architecture is the main cause for the unusual increased capacity during the early stages of cyclic charge/discharge.
Kinetics of the gas-phase reactions of OH with NO2 and with NO

The kinetics of the reaction, OH + NO2+ M → HNO3+ M (1), have been reinvestigated in order to provide data, using the same apparatus, for a series of third bodies, M. A discharge-flow–resonance-fluorescence technique was used to obtain third-order rate constants in the pressure range 1–5 Torr for M = He, Ar, N2, O2 and CO2. At T= 295 ± 3 K, the values of k1/10–31 cm6 molecule–2 s–1 were He, 16 ± 1; Ar, 16 ± 3; N2, 27 ± 2; O2, 26 ± 7; CO2, 45 ± 10 (95% confidence limit errors; systematic errors could contribute an additional 20% range). Similar investigations of the reaction, OH + NO + M → HONO + M (2), for M = He, Ar and N2 gave values of k2/10–31 cm6 molecule–2 s–1 of He, 6.0 ± 0.3; Ar, 7.4 ± 2.4; N2, 11 ± 1. The implications of the results for the atmospheric chemistry of Earth, Mars and Venus are discussed.
Dry Weight and Nitrogen Content of Chickpea and Winter Wheat Grown in Pots for Three Rotations

ABSTRACT Chickpea [Cicer arietinum (L.)] cultivars ‘ICCV-2’ and ‘Sarah’ were studied along with a control, multistrain, TAL 1148, and TAL 480 Bradyrhizobium strains to determine the effect(s) of cultivar and inoculum on dry weight (DW) and nitrogen (N) content of the legume, as well as soil mineral N, DW, and N content of wheat [Triticum aestivum (L.) emend. Thell. ] in a continuous wheat-legume rotation. Chickpeas were planted during the summer and harvested in the fall of 1992, 1993, and 1994. Vegetative growth from chickpeas was incorporated into the soil prior to wheat planting, and soil cores were taken at 35 to 48 d after chickpea harvests. Additional summer fallow treatments for the winter wheat part of the experiment received 0, 45, and 90 kg N ha−1 each year. Wheat plants were removed the following spring and stubble was incorporated into the soil before planting chickpeas in the summer. ‘Sarah’ chickpeas accumulated about the same or more shoot DW and shoot N compared to ‘ICCV-2’; whereas ‘ICCV-2’ generally produced more pod DW and pod N compared to ‘Sarah. ’ Inoculum had no significant effect on chickpea DW or N content. Wheat DW and N following legumes increased marginally after growing ‘Sarah’ chickpeas, as evidenced by higher values of some treatments. Only the multistrain or absence of inoculum in ‘Sarah’ chickpeas resulted in significantly greater wheat DW or N content compared to the fallow wheat receiving no added N fertilizer. The contributions from ‘ICCV-2’ chickpeas to wheat DW and N content were not significant. Soil mineral N, as well as wheat DW and N content, fluctuated or increased during this three-year study, which demonstrated some benefit from incorporation of chickpeas into a wheat-legume cropping system.
Platinum-Modified Nucleobase Pairs in the Solid State: A Theoretical Study

We present a theoretical study of a mixed adenine−thymine crystal complex of trans-a2 Pt(II) (a = CH3NH2) with Watson−Crick orientation of the bases, experimentally studied by Krizanovic et al. (J. Am. Chem. Soc. 1993, 115, 5538). Calculations are based on density functional theory with gradient-corrected exchange-correlation functionals. The results for the structural parameters compare well with X-ray data. The electronic structure near the gap exhibits the characteristic features of a square planar platinum(II) complex with π-acceptor ligands. Comparison with parallel calculations of the nonmetalated base pair helps clarify the role of the trans-a2 Pt(II) moiety.
Maximizing furfural concentration from wheat straw and Eucalyptus globulus by nonisothermal autohydrolysis

The autohydrolysis process as a method for selective extraction of hemicelluloses and conversion to furfural was proposed for lignocellulosic raw materials. Samples of wheat straw (WS) and Eucalyptus globulus (EG) were subjected to nonisothermal autohydrolysis, defined by temperature 180–240°C. Within a biorefinery scheme for the selected materials, the aim of this study is both (a) to optimize furfural processing technology to enable higher yields and improved productivity from EG and WS by autohydrolysis and (b) to not excessively degrade the remaining polymeric constituents (glucan) in solid to facilitate a potential later use. Differences in the rate of the dehydration reaction of xylose to furfural have been observed, and it is faster in the case of WS with respect to that observed for eucalyptus. In that form, 4.25 g/100 g raw material (26% of the initial xylan in WS) could be found at 220°C, and an increase in the temperature (240°C) yielded 4.54 g/100 g raw material, 28% of the initial xylan. In EG, the increase in the hydrolysis temperature (240°C) yielded liquor with higher contents of furfural (4.45 g/100 g raw material, 25% of the initial xylan) and acetic acid (4.49 g/100 g raw material) and smaller contents of arabinose and xylan. In WS, a faster dehydration is found. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1236–1242, 2015