Miracle-dz/UniFAR-FTUs huggingface dataset:
Chlorine deficiency in red clover grown in solution culture

Abstract Symptoms of chlorine deficiency occurred in red clover (Trifolium pratense, L.) grown, in solution culture, in a controlled environment cabinet with its air intake filtered through activated carbon. The first visible symptom was a curling of the leaflets on the youngest leaves. Within a few days, some newly expanded leaflets shrivelled completely, and older leaflets developed a brown necrosis which started at the tip and extended backwards particularly at the margins. Subsequently there was a general stunting of growth and the collapse of some petioles. The results of analysis of deficient plants indicated that the critical concentration of chlorine in the leaf + petiole of red clover was at least 200 μg g‐1 dry weight.
Application of fluorescence microscopy to a study of chemical problems

The review outlines the photophysical properties that a compound should possess if it is to be of value as a reagent for fluorescence microscopy. Applications of fluorescence microscopy and related techniques to the study of the uptake of dyes by fibres, the photodegradation of dyes and polymers (e.g. wool and lignin) and for determining the softening temperatures of polymers are described.
High‐Yield Synthesis and Electrochemical and Photovoltaic Properties of Indene‐C70 Bisadduct

[6, 6]‐Phenyl‐C61‐butyric acid methyl ester (PC60BM) is the widely used acceptor material in polymer solar cells (PSCs). Nevertheless, the low LUMO energy level and weak absorption in visible region are its two weak points. For enhancing the solar light harvest, the soluble C70 derivative PC70BM has been used as acceptor instead of PC60BM in high efficiency PSCs in recent years. But, the LUMO level of PC70BM is the same as that of PC60BM, which is too low for the PSCs based on the polymer donors with higher HOMO level, such as poly (3‐hexylthiophene) (P3HT). Here, a new soluble C70 derivative, indene‐C70 bisadduct (IC70BA), is synthesized with high yield of 58% by a one‐pot reaction of indene and C70 at 180 °C for 72 h. The electrochemical properties and electronic energy levels of the fullerene derivatives are measured by cyclic voltammetry. The LUMO energy level of IC70BA is 0.19 eV higher than that of PC70BM. The PSC based on P3HT with IC70BA as acceptor shows a higher Voc of 0.84 V and higher power conversion efficiency (PCE) of 5.64%, while the PSC based on P3HT/PC60BM and P3HT/PC70BM displays Voc of 0.59 V and 0.58 V, and PCE of 3.55% and 3.96%, respectively, under the illumination of AM1.5G, 100 mW cm−2. The results indicate that IC70BA is an excellent acceptor for the P3HT‐based PSCs and could be a promising new acceptor instead of PC70BM for the high performance PSCs based on narrow bandgap conjugated polymer donor.
Heat Transfer Predictions for Micro-/Nanochannels at the Atomistic Level Using Combined Molecular Dynamics and Monte

The thermal behavior of a gas confined between two parallel walls is investigated. Wall effects such as hydrophobic or hydrophilic wall interactions are studied, and the effect on the heat flux and other characteristic parameters such as density and temperature is shown. For a dilute gas, the dependence on gas-wall interactions of the temperature profile between the walls for the incident and reflected molecules is obtained using molecular dynamics (MD). From these profiles, the effective accommodation coefficients for different interactions and different mass fluid/wall ratio are derived. We show that Monte Carlo (MC) with Maxwell boundary conditions based on the accommodation coefficient gives good results for heat flux predictions when compared with pure molecular dynamics simulations. We use these effective coefficients to compute the heat flux predictions for a dense gas using MD and MC with Maxwell-like boundary conditions.
Determination of True Amino Acid Digestibility and Metabolizable Energy in Fermented Palm Kernel Meal with Aspergillus wentii TISTR 3075 for Chickens

The determination of energy and digestibility values of new added-value products is important for feed formulation. True amino acid digestibility and metabolizable energy of feedstuffs were evaluated in adult meat type crossbred chickens. Sulfur amino acids (cysteine and methionine) and lysine were limiting amino acids in palm kernel meal (solvent extract; PKM) and fermented palm kernel meal (FPKM) with Aspergillus wentii TISTR 3075. The FPKM with Aspergillus wentii TISTR 3075 lead to an increase in true amino acids digestibility except for arginine. The apparent metabolizable energy (AME; DM basis) of corn, PKM and FPKM were 3,628.88, 2,201.83 and 2,080.26 kcal/kg, respectively. The true metabolizable energy (TME) of PKM (DM basis: 2,958.21 kcal/kg) was slightly higher than FPKM (DM basis: 2,843.01 kcal/kg) while the nitrogen-corrected apparent metabolizable energy (AME n ), nitrogen-corrected true metabolizable energy (TME n ) of PKM (DM basis: 2,411.84 and 2,603.33 kcal/kg, respectively) were significantly higher than FPKM (DM basis: 2,153.11 and 2,333.07 kcal/kg, P = 0.03 and P = 0.02 respectively). Aspergillus wentii may use up nitrogen-free extract (NFE) in PKM as an energy source during the fermenting process, resulting in a lower metabolizable energy of FPKM when compared to PKM (without fermentation).
Relationship between plant type and root growth in rice

Abstract The relationship between plant type and root growth was examined using the root box technique. Correlation studies on 1,081 varieties or lines indicated that the deep root system is correlated with taU plant stature and low tiller number; it is not closely correlated with Iong growth duration. Subsequent studies on two isogenic lines of early Peta with different plant heights, however, indicated that plant height is not related to rooting depth. The same conclusion was reached from a comparison of three sorghum varieties with different plant heights. The shortest of the three varieties had the deepest root system. Examination of tillering habit and root growth of individual shoots (tiller or main culm) c1early showed that earIy tillers have more and longer roots than do Iate tillers regardless of the tiller order and the position of the node from which they emerge. Thus, a high tiUering plant tends to have a short root system. The advantages and disadvantages of low- or high-tillering varieties i.
Computational aspects of hydroformylation

The influence of transition metal complexes as catalysts upon the activity and selectivity of hydroformylation reactions has been extensively investigated during the last decades. Nowadays computational chemistry is an indispensable tool for elucidation of reaction mechanisms and for understanding the various aspects which govern the outcome of catalytic reactions. This review attempts to survey the recent literature concerning computational studies on hydroformylation and theoretical coordination chemistry results related to hydroformylation.
Investigation of Heavy Metal Levels in Street Dust Samples in Tokat, Turkey

Abstract The concentrations of heavy metals in the street dust samples collected from Tokat, Turkey have been determined using flame atomic absorption spectrometry after wet and microwave digestion. Good accuracy was assured by the analysis of standard reference material. Recoveries were nearly quantitative for all elements studied (≥ 95%). The mean concentration levels of Pb, Ni, Cd, Zn, Mn, Cu, Co, and Cr were found to be 149, 65, 3.0, 63, 285, 29, 20, and 30 µg/g, respectively. The concentrations of heavy metals in the samples vary depending on the traffic density.
COMPACTION AND SUPERCOILING OF SINGLE, LONG DNA MOLECULES BY HU PROTEIN

The bacterial cell contains the highly conserved protein HU in abundance. To characterize its architectural role, we studied the elastic behavior of single, supercoilable DNA molecules (tens of kilobases long) in solution with HU from B. stearothermophilus (BstHU) by a micromanipulation assay. We point out quantitative yet notable differences to the behavior of HU from E. coli (EcoHU) observed by others. Our main contribution here, however, is to characterize the interaction of BstHU with single molecules of DNA in arbitrary states of supercoiling. BstHU clearly distinguishes under- and overwound substrates, breaking the characteristic symmetry in the elastic response of bare DNA. We demonstrate that BstHU shifts the preferred linking number of the complex, consistent with a model in which bound proteins untwist the double helix. The model qualitatively explains various features, such as overall compaction and weaker dependence on supercoiling, by a softening of the DNA to twist and bending. Previously reported reversal of binding effects at protein concentrations above a threshold also extends to supercoiling. All observed effects are highly sensitive to salt concentrations. Their range and magnitude lend HU great versatility in dynamically altering the physical properties and organization of the nucleoid.
Thermal Stability of Robust Unsymmetrical Copperporphyrins with Multiple Diphenylamino and Nitro Substituents

The syntheses and thermal stability properties of a series of amino and nitro substituted copperporphyrins are described. The thermal decomposition temperatures of the porphyrins were determined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The on-set thermal decomposition temperatures of the unsymmetrical porphyrins were found to be high in the range of 350 – 405 °C (DSC), 374 – 441 (TGA in air), 395 – 411 °C (TGA under nitrogen atmosphere), and 410 – 424 °C (DTA in air). Substituent dependent thermal stability trends were also studied. The trend is variable depending on the thermal analysis technique utilized. Possible reasons for such variation are discussed. These porphyrins are thermally robust even in the melamine-based sol-gel matrix. Containing 20% by weight of the substituted unsymmetrical copperporphyrin, melamine-based sol-gel showed no indication of decomposition until −400 °C.
Size-dependent structural and electronic properties of Tin clusters (n≤100)

The results of a genetic-algorithms search for structures of titanium clusters with up to 100 atoms are presented. An empirical pair potential has been used in describing the interatomic interactions during the genetic-algorithms search. The resulting global-minimum structures have been used as starting geometries of geometry optimizations using a density-functional tight-binding method. Structural, energetic, and electronic properties are analysed and compared. Special attention is paid to the size dependence of the properties, including point groups, radial atomic distributions, bond lengths, moments of inertia, stability, Mulliken populations and frontier orbitals. Similarity functions are defined to facilitate the analysis of the growth of the clusters. It turned out that the empirical potential favours highly symmetric geometries, that exhibit small distortions upon relaxation using the electronic-structure method. Some larger, particularly stable clusters are fragments of the hcp bulk structure but an overall transition to bulk structure cannot be seen below 100 atoms.
Chemical vapor deposition of aluminum nitride thin films

The atmospheric pressure chemical vapor deposition of aluminum nitride coatings from hexakis(dimethylamido)dialuminum, Al_2(N(CH_3)_2)_6, and ammonia precursors is reported. The films were characterized by ellipsometry, transmission electron microscopy, x-ray photoelectron spectroscopy, Rutherford backscattering, and forward recoil spectrometry. The films were deposited at 100–500 °C with growth rates up to 1500 Å/min. The films showed good adhesion to silicon, glass, and quartz substrates and were chemically inert. Rutherford backscattering analysis revealed that the N/Al ratio was 1.15 ± 0.05 for films deposited at 100–200 °C and 1.05 ± 0.05 for those deposited at 300–500 °C. Films deposited at 100–200 °C had refractive indexes in the range 1.65–1.80 whereas indexes for films deposited at 300–400 °C were 1.86–2.04. The films were transparent in the visible region. The optical bandgap varied from 5.0 eV for films deposited at 100 °C to 5.77 eV for those deposited at 500 °C. Films deposited at 100–200 °C were amorphous whereas those deposited at 300–500 °C were polycrystalline.
Thermoluminescence behavior of magnesium oxide exposed to gamma and ultraviolet radiations

Magnesium oxide (MgO) has been investigated as a possible candidate for gamma (γ) dosimetry. One thermoluminescence (TL) peak was observed in the red emission band around 372 °C in the pristine sample. The glow curves indicate that the main TL peaks appear at nearly the same temperatures after γ and ultraviolet irradiations. The dose response has a linear behavior at intermediate dose levels 1–100 Gy, and then becomes sublinear at high dose levels 0.5–50 kGy. The dose dependence of the phototransfer TL signal is recorded in the γ dose range from 0.05 to 50 Gy. Fading studies over a period of 75 days show that the γ-irradiated aliquots faded by 32% when exposed to 1 Gy. Comparison of the results from the present work with those found in the literature shows that differences are sample- and instrument-dependent. The results further predict the potential of MgO as a phosphor in accident and industrial dosimetry taking into consideration the fading effects.
Carbon balance of a southern taiga spruce stand in European Russia

Abstract We present results from nearly three years of net ecosystem flux measurements above a boreal spruce stand growing in European Russia. Fluxes were measured by eddy covariance using conventional techniques. In all years examined (1998–2000), the forest was a significant source of carbon to the atmosphere. However, the magnitude of this inferred source depended upon assumptions regarding the degree of “flux” loss under conditions of low turbulence, such as typically occur at night. When corrections were not made, the forest was calculated to be only a modest source of C to the atmosphere (3–5 mol C m−2 yr−1). However, when the corrections were included, the apparent source was much larger (20–30 mol C m−2 yr−1). Using a simple model to describe the temperature dependencies of ecosystem respiration on air and soil temperatures, about 80% of the night-time flux was inferred to be from soil respiration, with the remainder being attributable to foliage, branches and boles. We used reasonable assumptions to estimate the rate of ecosystem respiration during the day, allowing an estimation of canopy photosynthetic rates and hence the annual Gross Primary Productivity of the ecosystem. For the two full years examined (1999 and 2000), this was estimated at 122 and 130 mol C m−2 yr−1, respectively. This value is similar to estimates for boreal forests in Scandinavia, but substantially higher than has been reported for Canadian or Siberian boreal forests. There was a clear tendency for canopy photosynthetic rates to increase with both light and temperature, but the slope of the temperature response of photosynthesis was less steep that that of ecosystem respiration. Thus, on most warm days in summer the forest was a substantial source of carbon to the atmosphere; with the forest usually being a net sink only on high insolation days where the average daily air temperatures were below about 18 °C. These data, along with other studies on the current balance of boreal ecosystems, suggests that at the current time many boreal forests might be releasing substantial amounts of carbon dioxide to the atmosphere. This observed temperature sensitivity of this ecosystem suggests that this might be a consequence of substantially higher than average temperatures over recent years.xs
Kinetics of Cationic Photopolymerizations of UV‐Curable Epoxy‐Based SU8‐Negative Photoresists With and Without Silica Nanoparticles

Summary: This paper reports on the photocuring kinetics of protonic-acid-initiated cationic polymerizations of UV-curable epoxy-based SU8-negative photoresist systems with and without silica nanoparticles, as assessed using photo-DSC, FTIR spectroscopy, UV-vis spectroscopy, and SEM. Photo-DSC analysis using an autocatalytic kinetic model demonstrated that the cross-link density and cure rate increased as the concentration of silica nanoparticles with surface silanol groups increased to 2.5 wt. -%. This result was confirmed by FTIR spectroscopy, and suggests that the presence of silica nanoparticles of up to 2.5 wt. -% promoted the cure conversion and cure rate of the UV-curable hybrid organic/inorganic negative photoresists due to the synergistic effect of silica nanoparticles acting both as an effective flow or diffusion-aid agent and as a proton-donor cocatalyst during the cationic photopolymerization process. The decrease in the cross-link density that occurred when the silica content was higher than 2.5 wt. -% was attributed to aggregation between silica nanoparticles due to their high surface energy. SEM photograph at the film-air interface of the UV-cured hybrid organic/inorganic photoresist containing 10 wt. -% silica nanoparticles.
Narrow‐Bandgap Diketo‐Pyrrolo‐Pyrrole Polymer Solar Cells: The Effect of Processing on the Performance

A study has reported on the application of a novel narrow bandgap polymer, poly[3,6-bis-(4'-dodecyl-[2,2']bithiophenyl-5-yl)-2,5-bis-(2-ethyl-hexyl)-2, 5-dihydropyrrolo[3,4-]pyrrole-1,4-dione] (pBBTDPP2) in photovoltaic cells. The conjugated polymer is based on alternating quaterthiophene (BBT) and diketopyrrolo-pyrrole (DPP) units with a bandgap of1.4eV, which is close to the optimum for single, bandgap polymer solar cells. After careful optimization of the processing parameters and morphology, the donor polymer in combination with C60 and C70 PCBM derivatives affords external quantum efficiencies of ~0.4 over a broad spectral range and power conversion efficiencies of 3.2 and 4.0%, respectively under simulated AM1.5G solar light conditions. Significant molecular weights of Mn=20000 and M w=67000g/mol (DPI)=3.35) also were obtained, as determined by gel permeation chromatography (GPC) using 1,2,4-trichlorobenzene as eluent
GC-MS AND IR STUDIES OF ETHANOLIC EXTRACT OF COLONIAL ASCIDIAN- POLYCLINUM MADRASENSIS SEBASTIAN, 1952

Many marine origin organic molecules have entered clinical studies for their medicinal value. Ascidians, a marine sedentary urochordate has drawn the attention of researchers for its versatility as medicine and nutrition. Polyclinum madrasensis is a colonial ascidian found in abundance along Tuticorin coast. The ethanolic extract of Polyclinum madrasensis was subjected to GC-MS study to determine the possible bioactive components. The analysis revealed the presence of twenty two compounds. Chemical components which are biologically active include n-Hexadecanoic acid, 4,8-dimethyl-Nonane-I-ol, 3-methyl1,2Cyclopentane-diol, 1,2-diisooctyl ester of Benzenedicarboxylic acid, 1-Iodo-Tridecane, 2butyl-octan-1-ol, Squalene, Cholesterol, Cholestan-3-ol, Dihydrotachysterol, 3-hydroxy-, (3a,17a)-Spiro[androst-5-ene-17,1'-cyclobutan]-2'-one and Diazoprogesterone. Major compounds are Cholesterol (23.01), Cholestan-3-ol (14.22), Squalene (10.50), nHexadecanoic acid (10.48) and Dihydrotachysterol (7.94). Of the twenty two compounds identified, thirteen compounds were reported for the first time from the ascidians of Indian water namely 4,8-dimethyl-Nonane-I-ol, (E)-5-Octadecene, 3-methyl-1,2-Cyclopentane-diol, 4,6,8-trimethyl-1-Nonane, Bis(2-ethylhexyl) ester of Hexanedioicacid, Methyl 2hydroxydodecanoate, 1-Iodo-Tridecane, 2-butyl-octan-1-ol, (1,2-dimethylpropyl)-1-methyl-2nonyl-cyclopropane, 6-methyl-octadecane, 2-oxomethyl ester of Octadecanoic acid, Dihydrotachysterol and 1,8,15,22-Tricosatetrayne. These compounds exhibited many biological activities such as anticancer, antiarthritic, antiasthmatic, antimicrobial, antioxidant, antiandrogenic, pesticide and so on. Infrared (IR) spectral study of this species indicates the presence of primary free N-H stretching, alkanes –CH2stretching, carboxylic acid and carbonyl compound.
Gas separation membranes made through thermal rearrangement of ortho-methoxypolyimides

ortho-Methoxypolyimides were prepared from 3,3ʹ-dimethoxybenzidine (DMAB) and hexafluoroisopropylidene diphthalic anhydride (6FDA). High molecular weights of the resulting polymers were achieved, and the physical properties of the materials were investigated. The polyimides exhibited excellent thermal properties and film-forming capabilities. Polyimides were treated at high temperatures to promote thermal rearrangement (TR) processes. The final composition of the TR polymers seems not to correspond to TR-polybenzoxazoles, as was the case when analogous ortho-hydroxypolyimides were exposed to similar thermal treatments. A detailed study was carried out to elucidate the actual mechanism of the thermal rearrangement, comparing ortho-hydroxypolyimides, ortho-acetylpolyimides and ortho-methoxypolyimides. Results led to the conclusion that the chemical nature of the final TR polymers attained from ortho-methoxypolyimides is complex since imide, lactam and benzoxazole groups all seem to be present after thermal treatment. Gas permeation properties exhibited by thermally treated ortho-methoxypolyimides compared well with those of other TR-PBOs, showing CO2 permeability of 540 Barrers.
Amperometric biosensor for hydrogen peroxide based on sol-gel/hydrogel composite thin film

A reagentless amperometric hydrogen peroxide biosensor was developed. Horseradish peroxidase (HRP) was immobilized in a novel sol-gel organic-inorganic hybrid matrix that is composed of silica sol and a grafting copolymer of poly(vinyl alcohol) with 4-vinylpyridine (PVA-g-PVP). Tetrathiafulvalene (TTF) was employed as a mediator and could lower the operating potential to -50 mV (versus Ag/AgCl). The sensor achieved 95% of the steady-state current in 15 s. Linear calibration for hydrogen peroxide was up to 1.3 mM with the detection limit of 2.5 x 10(-7)M. The enzyme electrode retained about 94% of its initial activity after 30 days of storage in a dry state at 4 degreesC.
Distribution of chain lengths and composition in terpolymers

The instantaneous distribution of chain composition for random terpolymers has been derived by adopting a similar strategy to that used by Stockmayer. The analytical result shows the same Gaussian behavior for the random terpolymer distribution. When the concentration of the third comonomer is low and they are almost individually dispersed along the chain (the quasiterpolymer case ), the explicit distribution is given by (the Stockmayer's copolymer result)*(ωt) t , where t and ω are the concentration and the relative probability of incorporating the third comonomer within a chain.
The prediction of hydrate formation in condensed systems

Because the potential formation of hydrates in condensed liquid systems is of increasing importance both in connection with pipeline transportation of hydrocarbon liquids and with the production of fluids from reservoirs near permafrost regions, researchers from the University of Alberta have developed a method for predicting hydrate-forming conditions in the water/liquid-hydrocarbon/liquid-hydrate region of such fluids. Experimental data obtained for five mixtures of methane and n-butane at temperatures ranging from 35.4/sup 0/ to 59.7/sup 0/F (1.9/sup 0/ to 15.4/sup 0/C) and pressures between about 170 and 2000 psi (1200 and 13,800 kPa) were accurately predicted by the procedure.