Miracle-dz/UniFAR-FTUs huggingface dataset:
Similarities and Differences of Low Salinity Polymer and Low Salinity LPS (Linked Polymer Solutions) for Enhanced Oil Recovery

Linked polymer solution (LPS) is nano-size particles made of hydrolyzed polyacrylamide (HPAM) cross-linked with aluminum citrate. The propagation of LPS has been compared to non-cross-linked polymers at low brine salinity condition. The possible differences in properties and potentials for oil recovery have been investigated using water-wet and intermediate-wet cores. The target oil for polymer flooding (PF) is assumed to be the portion of the reservoir that has been bypassed by water during waterflooding and not the residual oil saturation in flooded zones. Our recent studies have shown that a positive synergy can be obtained by combining low salinity and PF. It has been claimed in the literature that cross-linking polymer such as colloidal dispersion gels (colloidal dispersion gels (CDG), micron-size aggregates) or LPS (nano-size particles) would extend the application of polymers to also include change in residual oil saturation. The results of this study indicated higher pressure buildup when low salinity LPS was propagated through brine saturated cores compared to low salinity polymer solution. The pressure buildup was even stronger for high salinity LPS injection. In two phase flow experiments, both polymer and LPS under low salinity condition, showed approximately similar propagation and oil recovery potential when injected into water-wet and intermediate-wet cores.
Particle collisions and coalescence in fluids

Coagulation, in the physical context, is looked upon here first from the fundamental perspective of collision and coalescence of individual particles. A Monte Carlo technique is used to investigate the particle size distribution in a suspension of coagulating particles when one or more collision mechanisms operate. The effect of interparticle forces - hydrodynamic, van der Waals' and electrostatic - on the collision probability of the particles is examined. The results obtained are used to evaluate the well-known dynamic equilibrium hypothesis according to which an equilibrium particle size distribution is assumed to exist under the action of a given collision mechanism. It is shown that dimensional analysis cannot, in general, be used to predict steady state particle size distributions, mainly because of the strong dependence of the interparticle forces on the sizes of the interacting particles. The insight into particle kinetics thus gained from the Monte Carlo simulation of collision processes is used to develop a numerical simulation of a rectangular settling basin. The computer model follows the spatial and temporal development of the influent particle size distribution towards the outlet of the tank, accounting for all of the basic kinetics of particle collision and coalescence processes and including transport processes such as particle settling, advection, resuspension and turbulent mixing. The influence of the particle size-density relationship and floc deaggregation by turbulent shearing are also modeled. Of necessity, modeling of some of these processes has been somewhat empirical since the physical and biochemical nature of the flocs are unique to a particular suspension and their determination requires experimental work. The results of the simulations performed indicate that the particle size-density relationship, the collision efficiencies between flocs and the influent particle size distribution are of major importance to the performance of the sedimentation basin. Clearly, further modifications, Improvements and trials are needed in order to use the model for the design of new facilities. Nevertheless, the computer model may serve as a guide for selection of several design and operation variables for the successful treatment of a particular waste or the selective removal of pollutants whose concentration depends on the shape of the effluent particle size distribution.
Development of a new HPLC method for the determination of inorganic and methylmercury in biological samples with ICP-MS detection

In the present work a new HPLC method for the determination of mercury species in biological samples with ICP-MS detection was developed. Separation of inorganic (Hg2+) and methylmercury (CH3Hg+) was accomplished on a Hamilton PRP-X200 polymer-based cation-exchange column with a mobile phase of 50 mmol l−1 pyridine, 0.5% w/w L-cysteine and 5% v/w MeOH, at pH 2, within 8 min. The influence of chromatographic parameters, such as pH, salt concentration, organic modifier, and ion-pair reagent on the retention behaviour was evaluated. Based on peak areas, the experimental detection limits for inorganic and methylmercury were 0.05 and 0.08 μg Hg l−1, which corresponds to an absolute detection limit of 1.0 and 1.6 pg of mercury (20 μl injection volume). The liquid chromatographic method was successfully applied to the determination of inorganic and methylmercury in the two certified reference materials DORM-2 and DOLT-3, after a rapid and simple sample preparation procedure using hydrochloric acid.
The glucosinolates sinigrin and progoitrin are important determinants for taste preference and bitterness of Brussels sprouts

The glucosinolates, sinigrin and progoitrin, are related to the bitterness observed in Brussels sprouts. The role of these glucosinolates in taste preference for Brussels sprouts (Brassica oleracea var gemmifera) was studied with two different consumer taste panels and an analytical panel. Four different taste trials were conducted between 1989 and 1995 to study the role of sinigrin and progoitrin on taste preference and bitterness of sprouts. Sinigrin and progoitrin correlated negatively with taste preference of sprouts when their combined content was higher than 2·2 g kg−1. Under these conditions the overall preference for different Brussels sprouts cultivars, in two different trial designs, was accounted for, respectively, 64 (Novartis Seeds BV) and 86% (TNO) by the contents of the glucosinolates sinigrin and progoitrin. In two additional trials, in which the combined content of sinigrin and progoitrin of all cultivars was below 2·2 g kg−1, no relationship between taste preference and the content of both glucosinolates was observed. In the latter trials the content of sinigrin and progoitrin was found to be correlated with bitterness (r2multiple = 0·67 and 0·93, respectively) as assessed by an analytical panel. The results of the taste trials show that both bitterness and taste preference for sprouts are correlated with the content of sinigrin and progoitrin. Taste preference for sprouts is only correlated with sinigrin and progoitrin when their combined content exceeds 2·2 g kg−1, while bitterness is correlated with both glucosinolates for the whole studied content range. © 1998 Society of Chemical Industry.
Effect of the angular potential on the temperature control in dissipative particle dynamics simulations

Angular potentials in dissipative particle dynamics (DPD) simulation can describe the rigidity of rod segments in the rod–coil block copolymers and cause system instability monitored by the kinetic temperature. We studied the influence of the bending constant of angular potentials on the temperature control of the DPD simulation system by our defined two parameters, deviation temperature δ T and standard deviation SD T . Small bending constants have no obvious influence on the temperature control. For the large bending constants, a relation of δ T = aϕ b Δt c is constructed. Based on this relation, we can give the appropriate parameters to balance the requirement of the temperature control and the rigid formation of rod-like blocks correctly.
Prediction of botanical composition in grassland herbage samples by near infrared reflectance spectroscopy

Near infrared reflectance spectroscopy (NIRS) was evaluated as a method to predict the botanical composition of seminatural grassland in ‘dehesa’ systems. Samples of herbaceous biomass were harvested over four consecutive years, determining in each—by manual separation—the proportion by weight of the following taxonomic groups: grasses, legumes and the rest of the families in a single block (‘others’). After reconstructing the natural samples they were analysed by NIRS. One set of samples (calibration set) was selected for the development of the equations, assaying different mathematical treatments (log l/R, first derivative and second derivative). The ranges of coefficients of multiple determination and standard errors of calibration, respectively, for the various components were: grasses, 0.86 to 0.92 and 6.66 to 9.14; legumes, 0.77 to 0.81 and 6.82 to 7.43; and ‘others’, 0.85 to 0.88 and 8.17 to 9.54. The remaining samples not included in the development of the NIRS equations (prediction set) were used for the purposes of validating the best equations. Standard errors of performance were: grasses, 6.12; legumes, 7.56 and ‘others’, 7.70.
Phenolic acid content and sensory properties of two Spanish monovarietal virgin olive oils

In recent years, phenolic acids have received considerable attention as they are essential to olive oil quality and nutritional properties. This study aims to validate a rapid and sensitive method based on ultra-performance liquid chromatography/time-of-flight mass spectrometry (UPLC–TOF-MS) for analyzing the phenolic acid content of olive oil and assessing its impact on virgin olive oil (VOO) sensory attributes. Once this method was validated, we used it to evaluate the phenolic acid composition of several Spanish monovarietal virgin olive oils in relation to nine different olive ripening stages. The results obtained confirm that the methodology developed in this study is valid for extracting and analyzing phenolic acids from VOO. The phenolic acid content of the virgin olive oils sampled was proven to be influenced by the type of cultivar and olive harvest date. Therefore, phenolic acids might be used as potential markers for olive oil cultivar or ripening stage. Finally, the data obtained indicate that the sensory properties of VOO may be differently affected by its phenolic acid content depending on the type of cultivar. Practical applications: The method validated in the present study – based on UPLC-TOF-MS – allows experts to assess the phenolic acid content of different VOO cultivars (varieties). This application will probably be very useful to the olive oil industry. The reason is that our study revealed that phenolic acids have an impact on the sensory quality of VOO, which is essential to consumer preferences and choice. In addition, there are phenolic acids that are only found in a particular variety of olive oil obtained from fruits at a specific ripening stage. Consequently, phenolic acids could be used as potential markers for olive oil variety and harvest time.
Systematic structural and chemical characterization of the transition layer at the interface of NO-annealed 4H-SiC/SiO2 metal-oxide-semiconductor field-effect transistors

We present a systematic characterization of the transition layer at the 4H-SiC/SiO2 interface as a function of nitric oxide (NO) post-annealing time, using high-resolution transmission electron microscopy for structural characterization and spatially resolved electron energy-loss spectroscopy for chemical analysis. We propose a systematic method for determining transition layer width by measuring the monotonic chemical shift of the Si-L2,3 edge across the interface, and compare its efficacy to traditional measures from the literature, revealing the proposed method to be most reliable. A gradual shift in the Si-L2,3 edge onset energy suggests mixed Si-C/Si-O bonding in the transition layer. We confirm an inverse relationship between NO-anneal time and transition layer width, which correlates with improved channel mobility, enhanced N density at the interface, and decreased interface trap density. No excess C was noted in the interfacial region.
Growth and yield of bari mung-5 (Vigna radiata L. Wilczek) following TIBA application

An experiment was conducted to evaluate the effect of TIBA (0, 20, 50, 100, 150 mg/l) on the growth and yield attributes of BARI Mung‐5 laid out in RBD. Plant height decreased due to TIBA treatments. Number of branches and leaves per plant were found to increase in all the treatments at all the ages of growth except at 7 DAS and the maximum number of branches and leaves were recorded due to 20 mg/l TIBA treatment. Dry matter per plant increased due to 20 mg/l TIBA in most cases and was significantly highest at harvest. All the yield contributing characters showed positive response to 20 mg/l TIBA treatment. Number of pods and seeds per plant and fresh and dry weights of pods significantly differed from all other treatments. Increase in yield per plant and yield per hectare following 20 mg/l TIBA was 22.60 and 22.80% over the control, respectively. The highest harvest index was also recorded from 20 mg/l TIBA followed by control. DOI: http://dx.doi. org/10.3329/dujbs.v23i2. 20098 Dhaka Univ. J. Biol. Sci. 23(2): 179-185, 2014
A Comparative Study of Indirect Competitive ELISA and HPLC for Fumonisin Detection in Corn of the State of Paraná, Brazil

The performance of a monoclonal antibody (MAb)-based indirect competitive ELISA (ICELISA) for fumonisin detection in corn was evaluated using 150 post-harvest corn samples from the April 1995 and March-April 1996 crop, in the State of Paraná, Brazil. Compared to high performance liquid chromatography (HPLC), the correlation coefficient (r) of the results from the two methods was 0.94. The IC-ELISA detected total fumonisin levels of 1.1 to 1.5-fold higher than HPLC in 85 samples (56.6%). The concentration range of 1.0 to 5.0 μg g−1 was observed in 26% of samples analysed by ELISA and in 29% by HPLC. In addition, four samples (2.7%) showed an ELISA/HPLC ratio of 0.7 to 0.99 and seven samples (4.7%) a 1.0 ratio. In 29 (13.3%) samples, IC-ELISA detected 1.6 to 2.0-fold higher values than HPLC. These data showed high correlation (r = 0.91) of IC-ELISA and HPLC for fumonisin concentration in corn contaminated with ≤ 10 μg g−1, with a detection limit of 93 ng g−1. Matrix interference was minimized by diluting the sample before the ELISA assay. MAb-based IC-ELISA may be effectively applied for fumonisin screening in corn, with advantages of simplicity, ease of sample preparation and sensitivity.
Two New Chemical Constituents from the Rhizome of Sparganium stoloniferum

Sparganium (Bur-reed) is a genus of flowering plants, which contains about 20 species in temperate regions of both the Northern and Southern Hemispheres. Three Sparganium species, S. stoloniferum, S. angustifolium, and S. japonicum, grow in Korea. S. stoloniferum is widely distributed in the wet valley areas, and has been used as an emmenagogue, a galactogogue, and an antispasmodic agent in Chinese folk medicine, and also for the treatment of menstrual disorders and chronic hepatitis. Previous phytochemical investigations on this plant reported the isolation of pyrrole carboxylic acid ester, phenylpropanoid glycosides, and two sucrose esters. Aldose reductase inhibition, anti-inflammatory, and anti-thrombotic activities of an EtOH extract have also been reported. In our continuing study on the constituents of Korean medicinal plant sources, we have identified molecules from the rhizome of S. stoloniferum. Column chromatograpic purification of the MeOH extract of the rhizome of this source led to isolation of two new constituents (1-2), together with three known compounds (3-5). The structures of the new compounds (1-2) were determined through spectral analysis, and chemical means. The isolated compounds (1-5) were tested for cytotoxicity against four human tumor cells in vitro using a sulforhodamin B (SRB) bioassay. Compound 1 was isolated as a colorless gum, +4.0° (c 0.2, MeOH). The molecular formula C11H13NO6 was determined by the HR-FAB MS m/z 255.0743 [M] (calcd. 255.0743). Compound 1 displayed three proton signals at δH 7.02 (1H, m, H-5'), 6.92 (1H, m, H-3'), 6.22 (1H, m, H-4') in an H-NMR spectrum and five carbon signals at δC 160.1, 124.3, 121.0, 116.5, and 109.8 in a C-NMR spectrum, which were assignable to 1H-pyrrole-2-carboxylic acid. The H NMR spectrum also showed signals characteristic of 1,4-dimethyl malate group at δH 5.60 (1H, t, J = 7.0 Hz, H2), 3.78 (3H, s, OCH3-4), 3.73 (3H, s, OCH3-1), and 3.02 (2H, m, H-3). The corresponding carbon resonances of these protons were observed at δC 170.4, 170.1, 68.2, 51.8, 51.3, and 35.5 in the HMQC spectrum. In addition, H-H COSY correlations between the methine proton signal at δH 5.60 (t, J = 7.0 Hz, H-2), and the methylene proton signals at δH 3.02 (m, H-3) were observed. The HMBC correlations between the methoxy group at δH 3.78 (OCH3-4) and the carbonyl carbon at δC 170.1 (C-4) and the other methoxy group at δH 3.73 (OCH3-1) and carbonyl carbon at δC 170.4 (C-1) implied that two methoxy groups were present at C-1 and C-4. These data indicated the presence of a 1,4-dimethyl malate group. The HMBC spectrum showed that the methine proton at 5.60 (1H, t, J = 7.0 Hz, H-2) correlated with the carbonyl carbon at δC 160.1 (C-6') (Fig. 2). Thus, compound 1 was α [ ]D 25
Epstein-Barr Virus in Nasal Lymphomas Contains Multiple Ongoing Mutations in the EBNA-1 Gene

We have described 5 major subtypes of Epstein-Barr virus (EBV) based on variations in EBNA-1 sequences. These include P-ala (identical to the prototype B95.8 virus), P-thr, V-pro, V-leu, and V-val. Normal individuals often carry multiple EBV subtypes, the most common being P-ala, whereas EBV-associated tumors examined to date always contain a single subtype, which only on rare occasion is P-ala. The primary hypotheses that these observations generate are as follows: (1) Each of these EBV subtypes are naturally occurring, and in normal individuals the multiplicity of subtypes results from multiple infections. (2) EBV subtypes in normal individuals are generated in vivo from a single infecting virus subtype by mutations in EBNA-1. The second hypothesis essentially excludes the possibilities that the nonrandom association of certain subtypes with lymphomas is secondary to the geographic distribution of EBV subtypes and, if proven correct, could provide strong support for a direct role of EBV in tumorigenesis. In this report, we provide evidence for the latter hypothesis. We show that the P-ala EBV subtype present in most nasal lymphomas undergoes and accumulates multiple mutations consistent with the generation of variant species of EBNA-1 in vivo. This phenomenon is similar to the generation of quasispecies in RNA viruses and is the first description of in vivo generation of subtypes in DNA viruses. In RNA-based viruses, including human immunodeficiency virus and hepatitis C virus, the emergence of quasispecies is linked to replication infidelity and significantly influences disease processes through its effect on viral tropism, the emergence of viruses resistant to the host defenses or to therapy, and pathogenicity. The present data thus raise important questions relating to the mechanisms whereby these mutations are generated in EBV and their relevance to the pathogenicity of EBV-associated lymphomas.
Umströmung kugelförmiger Blasen mit innerer Zirkulation

Die Umstromung von einzelnen Kugelblasen mit innerer Zirkulation wurde theoretisch untersucht. Die Differentialgleichungen, die das Geschwindigkeits- und Druckfeld in der Umgebung der Blase beschreiben, berucksichtigen die vollstandigen Tragheitsglieder. Die Rechnungen haben ergeben, daszlig; sich die Stromung bis Re = 200 mit Sicherheit auf der Blasenruckseite nicht ablost. Es kommt vermutlich erst dann zu Ablosungen, wenn die Kugelblase deformiert wird, d. h. wenn die Kugelblase wegen Volumvergroszlig;erung in die Ellipsoidblase ubergeht. Die ablosungsfreie Umstromung der Kugelblase ist eine Folge der Beweglichkeit der Phasengrenzflache. Aus den berechneten Geschwindigkeits- und Druckverteilungen um die Blasen lieszlig;en sich die Widerstandsgesetze ermitteln, fur die einfache Gleichungen aufgestellt wurden. Sie werden durch die Ergebnisse experimenteller Untersuchungen sehr gut bestatigt. Die Gesetze werden mit bereits bekannten dazu verwendet, die Aufstiegsbewegung formbestandiger und formdynamischer Blasen in zusammenfassender Weise zu behandeln.
XPS and ISS studies on the interaction of H2S with polycrystalline Cu, Cu2O and CuO surfaces

The first steps of H 2 S adsorption have been studied on polycrystalline copper samples, which are more relevant to industrial copper samples than to single-crystal surfaces. The tools for characterization are ultrahigh vacuum spectroscopic methods, such as x-ray photoelectron and ion scattering spectroscopies. The H 2 S adsorption on metallic copper and on the corresponding Cu 2 O and CuO oxides is dissociative and highly dependent on the chemical nature of the exposed surface rather than on the temperature, from room temperature up to 623 K. In our conditions, Cu° sulphidation deals with the top Cu° layer whereas two to three oxide surface monolayers are modified at H 2 S saturation. The results on oxides are interpreted by an oxygen/sulphur replacement mechanism following the dissociative adsorption. Contaminated copper surfaces by phenanthrene or H 2 O treatments are hardly sulphided. As far as surface reactivity is concerned, the adsorbed sulphide species have been shown to be quite strongly bound to the different surface states tested in this work: only oxidative treatments induce desorbing products at 623 K
Kinetics and Mechanism of Non-Isothermal Decomposition of Ca(II)-, Sr(II)- and Ba (II)- Cross-Linked Divalent Metal-Alginate Complexes

The kinetics of thermal decomposition of Ca(II)-, Sr(II)- and Ba(II)- cross-linked metal–alginate biopolymeric complexes as biocatalysts have been studied using thermogravimetric (TG) and differential thermogravimetric (DTG) techniques in static air. The TG curves showed three stages of weight loss, whereas the DTG indicated the presence of a series of thermal peaks associated with the TG curves. The thermal dehydration of the coordinated water molecules was found to occur in the first stage, followed by decomposition of the formed dehydrated complexes through the other following stages. The second stage was corresponding to the formation of oxalates as intermediate fragments, whereas the third stage indicated the formation of metal oxides as final product of such decomposition. The kinetic parameters were computed by different models and tentative decomposition mechanism is discussed.
Crystallite structure of cellulose

The crystallite structure of cellulose has been elucidated through analyses of the degradations of model compounds by gel-permeation chromatography. These compounds include single crystals of cellulose triacetate, regenerated cellulose from single crystals, precipitated celluloses from solutions, and commercial regenerated cellulose. The corresponding distribution profiles are found to follow the Keller transformation, which is a characteristic behavior of the folded crystals of synthetic polymers. It is also found that the leveling-off DP of cellulose is a first-order approximation of the corresponding fold length. A detailed folding chain model for the regenerated cellulose was constructed, and the various aspects of the structure are discussed. The kinetic data and the degradation products of native celluloses were also analyzed and found to obey the ruling of the chain fold model but not the conventional fringe-micellar model. In addition, an iodine-staining experiment pinpoints a minimum of 1.5% of true amorphous material; this is in quantitative agreement with the conformation analysis for the six-fold helical β-loop bonds. It is therefore suggested that the same chain-fold conformation is applicable to the native polymer. The hydrolysis of cellulose is found to be composed of a triple mode of degradation, i.e., a first-order random scission at the folds, a zero-order peeling reaction at the ends of the crystallites, and a first-order random scission on the lateral surfaces of the cellulose.