Miracle-dz/UniFAR-FTUs huggingface dataset:
Differential Pulse Voltammetric Determination of 8‐Aminoquinoline Using Carbon Paste Electrode

Abstract This paper describes the differential pulse voltammetric determination of 8‐aminoquinoline using carbon paste electrode. The optimum parameters for this determination were established (supporting electrolyte, pH, time of accumulation). In 0.1 mol · dm−3 H3PO4, it is possible to determine 8‐aminoquinoline down to 2.10−6 mol · dm−3 by differential pulse voltammetry. And, 0.1 mol · dm−3 NaOH enables us to achieve the limit of determination 2.10−7 mol · dm−3 using adsorptive stripping voltammetry. The possibility of determining 8‐aminoquinoline in the presence of 5‐aminoquinoline was also investigated. This research was supported by the Grant Agency of the Czech Republic (grant no. 203/03/0182).
Effect of the structural parameters of a series of fluoromonoacrylates on the surface properties of cured films

A series of fluorinated acrylates [F(CF2)q(CH2)pOCOCHCH2, where q = 8 and p = 2 ÷ 11) were synthesized and used as comonomers in the photopolymerization of acrylic systems. These fluoroacrylates were synthesized in a three-step procedure through the radical addition of perfluoroalkyliodides to an unsaturated alcohol followed by their acrylation. The mixtures, containing up to 0.8% (w/w) of the comonomers, produced transparent films after UV curing; they showed changes in the surface properties as a function of the comonomer type and concentration. With contact-angle and X-ray photoelectron spectroscopy analyses, the relationship between the structure of the monomers and the surface properties of the UV-cured films was investigated: the wettability decreased, depending on the length of the fluorinated group (q value) and the hydrogenated segment of the monomer (p value). © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4227–4235, 2001
Heterogeneous Enantioselective Hydrogenation of Ethyl Pyruvate Catalyzed by Cinchona-Modified Pt Catalysts: Effect of Modifier Structure

The effect of the structure of chiral modifiers derived from natural cinchona alkaloids on the enantioselectivity and rate of the Pt/Al2O3-catalyzed hydrogenation of ethyl pyruvate was investigated. The influence of the following structural elements was studied: the cinchonidine versus the cinchonine backbone; effect of the nature and the size of substituents attached to C9; effect of partial hydrogenation of the quinoline ring; effects of changes of the substituent at the quinuclidine moiety. The strongest effects on ee and somewhat less on rate were observed for changes in the O−C9−C8−N part of the cinchona alkaloid and for partial or total hydrogenation of the quinoline rings. The nature of the substituents in the quinuclidine part had a comparably minor influence. The solvent was found to have a significant effect on enantioselectivity and rate. In acetic acid, the best results were obtained with O-methyl-10,11-diydrocinchonidine (ee's up to 93%), whereas dihydrocinchonidine was the most effective mo.
Hydrothermal Processing of Chlorinated Hydrocarbons in a Titanium Reactor

Experiments are reported on the oxidative hydrothermal destruction of chlorinated organics in a cor rosion-resistant titanium reactor. Oxidation reaction conditions were 250−500 °C near 650 bar and reaction times of 30−100 s in a continuous-flow reactor. Trichloroacetic acid, trichloroethylene, and 1,1,1-trichloroethane behaved similarly. The organic concentration was ∼1.5 wt %; hydrogen peroxide was the oxidizer; sodium bicarbonate was added to achieve neutral pH. Hydrolysis occurs at low temper ature, producing chloride ion and secondary organics. Carbon dioxide is the sole carbon product at 500 °C. Sodium nitrate and sodium nitrite were also found to be effective oxidizers. Corrosion of the titanium was found to be slight (<0.038 mm/yr). The reaction mixture is likely not a single phase at these conditions. The destruction efficiency for trichloroethylene was estimated as 99.96% at 450 °C and 60 s, with <0.02% conversion to volatile chlorinated organic byproducts.
A New Steroid Glycoside Derivative from Acorus calamus L.

A new steroid glycoside derivative, 4'-O-docosanoyl-3-O-beta-D-glucosyl-sitosterol, along with six known steroids has been isolated from the ethanol extract of the rhizoma of Acorus calamus L. The structures of the new and known compounds were established on the basis of extensive I D and 2D NMR spectral data.
EVALUATION OF LABORATORY-MEASURED SOIL PROPERTIES AS INDICATORS OF SOIL PHYSICAL QUALITY

Routine soil analyses provide an approach for assessment and monitoring of soil quality and targeted implementation of management practices, but suitable indicators are mostly undefined. We used three long-term experiments on several soil types where maize (Zea mays L.) was grown under different tillage (no till and plow till), rotation (continuous maize and maize after grass), and harvesting (silage and grain) methods to identify suitable indicators for evaluating soil physical quality. Disturbed and undisturbed soil samples were collected, and laboratory-based analyses were performed for water-stable aggregation, saturated hydraulic conductivity, several pore size parameters, penetration resistance at &PSgr; = −10 MPa, and bulk density. Sensitivity to management, expense of measurement, measurement consistency, and relevance to critical physical soil processes were used as criteria to evaluate indicator suitability. Indicators varied significantly seasonally and by soil type, and several showed significant differences and trends between management treatments. Small water-stable aggregates (0.25-2 mm) showed the most consistent and significant treatment differences. Bulk density, available water capacity, and air-filled pores at field capacity (PO > 30) were also related to treatment effects and had low variability. Penetration resistance and effective porosity (PO > 0.2) were not sensitive to management practices, whereas aeration pores and saturated hydraulic conductivity were too variable to use as indicators. Several indicators measured on undisturbed cores may be predicted from those measured from disturbed samples using pedotransfer functions. Small water-stable aggregates (0.25-2 mm), available water capacity, bulk density, and PO > 30 appear most promising as indicators for routine evaluation and monitoring of soil physical quality.
Optimal side‐chain packing in proteins and crystallographic refinement

Amino acid side chains often adopt one of a few distinct, physicochemically favourable conformational states called rotamers. Rotameric preferences and compact packing are sufficient to estimate the conformations of most side chains, as demonstrated by approaches such as SCWRL in homology modelling, but such algorithms have not yet been applied to protein crystallographic refinement. SCWRL's combinatorial optimization algorithm was adapted for assigning side-chain rotameric states that maximize the electron density map occupation while minimizing steric clashes. Our program (OPSAX) was tested on five proteins by introducing error in main chains and comparing the subsequent CNS-only and CNS/OPSAX refinements. The latter refinement was also extended to multiconformer models. A sequence-assignment exercise examined whether CNS/OPSAX refinement can discriminate between correct and incorrect assignments at various artificially lowered resolutions. The composite CNS/OPSAX refinement yielded better R_{\rm free} values than CNS-only refinement. A further drop in R_{\rm free} was observed with multiconformer refinement. For complete main chains, the correct sequence could be discriminated efficiently in most cases even for a low observation-to-parameter ratio of 4, indicating that the OPSAX approach should find useful applications in protein X-ray refinement.
The Predictive and Guidance Value of Signet Ring Cell Histology for Stage II/III Colon Cancer Response to Chemotherapy

Purpose To evaluate the predictive and guidance value of signet-ring cell carcinoma for chemotherapy response in stage II/III colon cancer. Methods Eligible patients were recruited from the Surveillance, Epidemiology and End Results (SEER) database. The differences between adenocarcinoma (AD) and SRCC groups in the incidence of patients’ demographic and clinical characteristics were analyzed by Pearson’s chi-squared (×2) test. Survival was analyzed using the Kaplan–Meier method, and the differences were determined by the log-rank test. Some Cox regression models were built to assess hazard ratios (HRs) of different variables with 95% confidence intervals (95% CIs). Results In stage II AD, it was found that the receipt of chemotherapy had significantly 12.6% decreased risk of cancer-specific mortality (HR = 0.874, 95% CI = 0.825–0.927, P < 0.001). In stage II SRCC, however, the receipt of chemotherapy had significantly 70.00% increased risk of cancer-specific mortality (HR = 1.700, 95% CI = 1.032–2.801, P = 0.037). In stage III AD, it was found that the receipt of chemotherapy had significantly 45.3% decreased risk of cancer-specific mortality (HR = 0.547, 95% CI = 0.530–0.564, P < 0.001). In stage III SRCC, the receipt of chemotherapy had significantly 24.6% decreased risk of cancer-specific mortality (HR = 0.754, 95% CI = 0.632–0.900, P = 0.002). Conclusions The cancer-specific survival (CSS) difference between AD and SRCC was not statistically significant in stage II colon cancer. We provided the first compelling evidence that chemotherapy should not be treated in stage II SRCC, while stage III SRCC should be treated with chemotherapy.
Ferrocene-Nafion Modified Electrode And Its Catalysis For Cerium (IV)

Abstract Ferrocene-Nafion modified electrode is prepared, it exhibits an interesting electrocatalysis for Ce(IV) reaction. Many investigations have been done on ferrocene (Fc) derivative and polymer modified electrodes,1–6 but seldom reported the modified electrodes simply with Fc containing no substituents. Because in the latter case it was very difficult to attach the modifier to the electrode surface by conventional methods such as plasma polymerization,1 electrodeposit,2 electropolymerization,3 covalence link,4 ion exchange5 and polymer coating6 etc. Nafion modified electrodes7–10 have attracted much interest for its ion exchange property. Considering Nafion possesses another property-hydrophobic interaction, here we propose a noval modified electrode with complex Fc by the help of Nafion. The Fc-Nafion modified electrode prepared shows well defined cyclic voltammogram of Fc. It has more stable and reversible voltammetric characteristics compared with other Fc derivative electrodes. What interesting c.
NUTRIENT PARTITIONING IN POTTED PEACH (PRUNUS PERSICA L.) TREES SUPPLIED WITH MINERAL AND ORGANIC FERTILIZERS

The aim of the experiment was to evaluate the effect of organic fertilization on nutrient uptake and partitioning in potted peach trees. The study was carried out on 72 peach (Prunus persica L.) plants. The following treatments were compared: 1) unfertilized control, 2) mineral fertilization [713 mg nitrogen (N), 119 mg phosphorus pentoxide (P2O5), 476 mg potassium oxide (K2O) pot−1], 3) cow manure (119 g dw pot−1) and 4) compost (119 g dw pot−1). Compared to the untreated control, plant biomass was improved by supplying cow manure and compost. Potassium concentration in fine roots and leaves was higher in compost treated trees. Leaf concentrations of calcium (Ca) and magnesium (Mg) were decreased by applications of compost and cow manure. Nutrient concentrations in fine roots were always positively correlated with nutrients in coarse roots, only N showed a negative correlation. With the exception of Ca and Mg, macronutrients removed by trees were higher after compost fertilization than in unfertilized controls.
Treatment of Stormwater Runoff and Landfill Leachates Using a Surface Flow Constructed Wetland

A surface flow wetland was constructed in the Burnside Industrial Park, Dartmouth, Nova Scotia, to treat stormwater runoff from the surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The aim was to protect a freshwater ecosystem that consists of a 4.6 km long brook and two lakes. The ability of the constructed wetland to retain iron and manganese from the influent water was investigated and the change in pH of the water as it flowed through the cells was assessed. In 2004, the total iron removal efficiency of the constructed wetland ranged from a low of 47.13 % to a high of 84.74 % and in 2006 ranged from a low of 35.56 % to a high of 78.49 % depending on rain events. The outlet total iron concentrations in 2006 were not significantly different from those reported for 2004. In 2004, the total manganese removal efficiency of the constructed wetland ranged from a low of 25.75 % to a high of 51.61 % and in 2006 ranged from a low of 0.0 % to a high of 33.33 % depending on rain events. The inlet and the outlet total manganese concentrations in the constructed wetland from August to October 2006 were significantly higher than the inlet and the outlet total manganese concentrations reported for August to October 2004 because water levels in the constructed wetland were very low and the average pH of the outlet water was lower in 2006. In 2004 and 2006, the pH of the water in the constructed wetland had average inlet values of 6.70 and 6.26 and average outlet values of 7.28 and 6.70, respectively.
Effect of varied intensities of resistance training on explosive power

Resistance training is recognised as one of the most effective and efficient trainings to enhance various aspects of motor fitness. Standard and scientific methods of resistance training are necessary in the field of sports to improve the levels of performance. The purpose of the present study was to find out the effect of varied intensities of resistance training on explosive power. The subjects for this study were randomly selected from among the first year bachelor of physical education students during the year 2017-2018, Department of Physical Education and sports sciences, Annamalai University. Their age ranged between 18 to 21 years and they were segregated into four groups, each group consisting of 15 subjects, following the routine procedures of selection of subjects. The first group underwent high intensity resistance training programme, the second group underwent medium intensity resistance training programme the third group underwent low intensity resistance training programme and the fourth group acted as control and did not undergo any systematic training programme. Thus the high, medium and low intensity resistance training were consisted as three experimental variables and explosive power consider as one criterion variable for the present study. All the subjects were tested on explosive power before the commencement of the training programme. Thereafter three varied intensities of resistance training were given 3 days a week for 10 weeks for the three experimental groups and the control group did not participate in any systematic programme. The subjects were tested again on explosive power after the completion of training programme. To nullify the variation in the pre-test means, analysis of covariance (ANCOVA) was applied and the adjusted post-test means were tested for significance. If the ‘F’ ratio was significant Scheffe’s post-hoc test was applied to find out the significant differences if any, among the paired means. The level of significance was set at 0.05 level. the results shows that, high, medium and low intensity training groups showed significant improvement in explosive power as compared to control group. The medium intensity resistance training programme significantly improved explosive power when compared to high and low intensity groups. However there was no significant difference in the explosive power between high and low intensity groups. So it is concluded that the medium intensity training is better than high and low intensity resistance training in improving explosive power.
Ionic liquids in the electrochemical valorisation of CO2

The development of electrochemical processes for using captured CO2 in the production of valuable compounds appears as an attractive alternative to recycle CO2 and, at the same time, to store electricity from intermittent renewable sources. Among the different innovative attempts that are being investigated to improve these processes, the application of ionic liquids (ILs) has received growing attention in recent years. This paper presents a unified discussion of the significant work that involves the utilisation of ILs for the valorisation of CO2 by means of electrochemical routes. We discuss studies in which CO2 is used as one of the reactants to electrosynthesise value-added products, among which dimethyl carbonate has been the focus of particular attention in the literature. Approaches based on the electrochemical reduction of CO2 to convert it into products without the use of other carbon-based reactants are also reviewed, highlighting the remarkable improvements that the use of ILs has allowed in the CO2 electroreduction to CO. The review emphasises on different aspects related to process design, including the nature of IL anions and cations that have been used, the working conditions, the electrocatalytic materials, the electrode configurations, or the design of electrochemical cells, as well as discussing the most relevant observations, results and figures of merit that the participation of ILs has allowed to achieve in these processes. Several conclusions are finally proposed to highlight crucial challenges and recommendations for future research in this area.
Comparison Between Long- and Short-Chain Organoclays for Oil Removal from Salty Waters

Two commercial powdered organoclays, Cloisite 15A and Cloisite 30B, as long-chain organoclays, and two organically modified clays with tetramethylammonium chloride (TMA-clay), as short-chain organoclays were used in this study to investigate their potentials for crude oil removal from salty waters. Batch experiments were performed to examine the effect of contact time and pH on the adsorption process. The results showed that the equilibrium time was reached within 25–30 and 50–55 minutes of contact time for long and short-chain organoclays, respectively. In addition, adsorption isotherms were obtained at an optimum pH value of 11.73 and temperature of 19°C for which initial oil contents varied in the range of 100 to 2000 ppm. Experimental results indicated that the sorption of oil onto Cloisite 15A, Cloisite 30B and the organically modified clays can be described by Freundlich isotherm and oil sorption followed the order of modified Cloisite Na > Cloisite 30B > Cloisite 15A > a modified local clay.
Generation of Active Oxidant Species by Pulsed Dielectric Barrier Discharge in Water-Air Mixtures

Experimental research into the electrical and optical parameters of pulsed dielectric barrier discharge (PDBD) was undertaken. PDBD was applied to humid air containing water droplets as a means of water oxidative treatment with short-living species generated in the discharge zone. In spectral analysis of PDBD, only small concentrations of nitric oxides were detected at the resulting electric field strength and electron mean energy sufficient for generation of OH-radicals. The water droplets served as electric field strength concentrators: PDBD was ignited close to the water droplets' surface.
Determination of oxygen in acid-treated high-purity niobium by X-ray photoelectron spectroscopy

ABSTRACT High-purity niobium was immersed in nitric acid and hydrofluoric acid for two minutes and the resulting product was characterized. Scanning electron microscopy was employed to characterize the morphology of the acid treated product. Inert gas fusion was used for determination of oxygen in the high-purity niobium. X-ray photoelectron spectroscopy was employed to characterize the surface ratio of oxygen to niobium. The oxygen concentration was 30 ppm in the acid-treated material and 70 ppm in the untreated material. X-ray photoelectron spectroscopy was employed to characterize the reduction of oxygen at the surface. The ratio of oxygen to niobium decreased from 9.75 to 2.60 without treatment compared to acid treatment for two minutes. The concentrations of adsorbed water and niobium oxide decreased following etching. The acid-treated high-purity niobium was characterized by argon ion bombardment; adsorbed water molecules and niobium oxides were not present but non-lattice oxygen was observed.
A Consistent Reaction Scheme for the Selective Catalytic Reduction of Nitrogen Oxides with Ammonia

For the first time, the standard and fast selective catalytic reduction (SCR) of NO by NH3 are described in a complete catalytic cycle that is able to produce the correct stoichiometry while allowing adsorption and desorption of stable molecules only. The standard SCR reaction is a coupling of the activation of NO by O2 with the fast SCR reaction, enabled by the release of NO2. According to the scheme, the SCR reaction can be divided into an oxidation of the catalyst by NO + O2 and a reduction by NO + NH3; these steps together constitute a complete catalytic cycle. Furthermore, both NO and NH3 are required in the reduction, and finally, oxidation by NO + O2 or NO2 leads to the same state of the catalyst. These points are shown experimentally for a Cu-CHA catalyst by combining in situ X-ray absorption spectroscopy (XAS), electron paramagnetic resonance (EPR), and Fourier transform infrared spectroscopy (FTIR). A consequence of the reaction scheme is that all intermediates in fast SCR are also part of the s.
Apports de la tomographie atomique dans l'observation et l'analyse des interfaces

la sonde atomique tomographique developpee a l'universite de Rouen est une nouvelle technique combinant microscopie et microanalyse quantitative a une echelle proche de la maille cristalline. L'instrument produit pour chaque espece, une image tridimensionnelle du petit element de volume analyse (10×10×100 nm 3 ) resolue a l'echelle du plan atomique. Differentes applications de cette nouvelle technique dans l'etude des interfaces interphase et des joints de grains sont donnees: segregation du chrome aux interfaces y /α 2 dans les aluminiures de titane, nano-precipitation aux joints interphase ferrite-cementite dans des aciers perlitiques, chimie locale des joints de grains dans des superalliages a base de nickel.
Effect of Electric Field on the Rheology in the Smectic and the Nematic Phases of Octyl Cyanobiphenyl

Abstract Changes of the rheology under the application of an electric field, electrorheological (ER) effect, are studied in the smectic A (SmA) and the nematic (Ne) phases of 4-n-octyl-4-cyanobiphenyl (8CB). In the SmA phase, the electric field induces a large decrease in the viscosity except just below the SmA-Ne transition point TAN. where an increase in the viscosity is observed. While in the Ne phase, an increase in the viscosity, which is strongly dependent on temperature, is observed upon application of the electric field; near TAN a peak in the viscosity is observed below 1 KV mm−1 followed by a gradual decrease to a constant value at higher electric field. whereas far from TAN the viscosity increases monotonically with the electric field and saturates at high enough electric field. These results are discussed on the basis of the orientational change of the director and/or the smectic layer.