Miracle-dz/UniFAR-FTUs huggingface dataset:
The Bulk Analysis of Silicate Rocks by Portable X‐Ray Fluorescence: Effect of Sample Mineralogy in Relation to the Size of the Excited Volume

This paper examines the limitations arising from sample mineralogy when a portable X-ray fluorescence instrument is applied to the direct in situ analysis of silicate rocks. Estimates were made of the size of the excited volume from which the X-ray fluorescence signal originates by calculating the critical penetration depth for selected X-ray lines. Measurements were made of the variations in detected intensities over the area of the P-XRF analyser window and showed that, using radioisotope sources incorporated in the instrument used in this study (Spectrace TN9000), excitation intensities were six to ten times greater at the centre compared to the edge of the analyser window. These data indicated that the region of the sample at the centre of the window will make an enhanced contribution to detected spectra. Replicate measurements on slabs of rock selected to represent fine-to coarse-grain size textures indicated the magnitude of the sampling precision that can be achieved in the direct analysis of silicate rocks. Typical values were better than 5% relative standard deviation of the mean from an average of five determinations on fine- to medium-grained rocks and better than 10 % relative standard deviation in a single determination on these samples. Cet article etudie les problemes lies a la mineralogie, qui apparaissent quand on utilise un appareil portable de fluorescence X pour l'analyse in situ de roches silicatees. La taille du volume excite, a l'origine du signal de fluorescence X, est estimee en calculant la profondeur critique de penetration pour quelques frequences specifiques. Les variations des intensites d'excitation a l'interieur de la fenetre de l'analyseur X ont ete mesurees et montrent que, avec la source radioactive qui equipe l'appareil utilise dans cette etude (Spectrace TN 9000), les intensites d'excitation sont six a dix fois plus grandes au centre que sur les bords de la fenetre. Ces resultats montrent que la region situee au centre de la fenetre aura une contribution surestimee au spectre total. Les analyses repetees de tranches de roches de textures variant d'un grain fin a un grain grossier donnent un ordre de grandeur de la precision escomptable lors d'analyses pratiquees in situ sur des roches silicatees. Pour les roches a grain fin et moyen, la deviation standard relative obtenue sur la moyenne de cinq determinations est inferieure a 5%; elle est inferieure a 10 % sur chaque analyse individuelle.
MultivariateStatisticalModeling:Alternative Approachto Test Evaluation,Appliedto CountingReticulocytes by FlowCytometry

W P. Oosterhuis,”4 A. H. Zwinderman,2 T. A. Modderman,’ R. B. Dinkelaar,’ and H. J. van der Helm3 We present a statisticalpath analysis model for the evaluationoftwo testsintheabsenceofa “goldstandard” method. This model is applied to the evaluation of flowcytometricand visualreticulocyte countingbyusingasthe comparison methoda combination ofthreehematological measurements: hemoglobin concentration (HGB), mean cellular volume (MCV), and erythrocyte density width (EDW). We assumed that, in general,a higherreticulocyte count is associatedwith a lowerHGBvalueandwith greater values for MCV and EDW. Applying thisassumption and the statisticalmodel,we demonstrated that flow cytometry was superior to visualreticulocyte counting in the low-valuerange studied.The path analysismodelis potentially applicable in othercases where two testsare to be compared,and when no gold standard is available. Addftlonal K.yphrssss: hemoglobin erythrocytes We compared the traditional visual method for reticulocyte counting with a new method based on flow cytometry with fluorescent dyes that selectively bind to
Adsorptive Stripping Voltammetry of 9‐Phenanthrol in the Presence of Copper at the Static Mercury Drop Electrode—Basis for Quantitative Determination of PAH Metabolite in Biological Materials

Abstract The electrochemical behavior of 9‐phenanthrol in the presence of copper (II) at a static mercury drop electrode was investigated to provide the basis for development of an inexpensive, sensitive, and reliable method for determination of polycyclic aromatic hydrocarbon (PAH) metabolites in biological matrices. Optimum experimental conditions for analytical applications were obtained in 0.005 M NaOH solution using an accumulation potential of −0.25 V, a scan rate of 5 mV. s−1, a pulse height of 25 mV, and a differential pulse scan mode. The response of 9‐phenanthrol is linear over the concentration range 1.0–12.0 ppb. For an accumulation time of 5 minutes, the detection limit was found to be 0.2 ppb (1.03×10−9 M). The more convenient relation to measure the 9‐phenanthrol in the presence of copper and other metals was also investigated. The utility of the method was demonstrated by the presence of 9‐phenanthrol in samples of sea water and human urine. Cyclic voltammetry was used to characterize the interfacial and redox behavior.
Cyclic electron flow around PSI functions in the photoinhibited rice leaves

We investigated the regulation mechanism of cyclic electron flow around photosystem I (CEF-PSI) in the rice leaves which suffered from photosystem II (PSII) photoinhibition. High-light (HL) treatment [2000 µmol photon m–2 s–1 at 0% carbon dioxide (CO2), 2% oxygen (O2) and 25°C] of rice leaves decreased both the maximum quantum efficiency of PSII (Fv/Fm) and the light-dependent O2-evolution rate [V(O2)]. High-light treatment did not affect the relative electron flux in PSI [Φ(PSI) × PFD]. In non-treated leaves, increasing in the photon flux density (PFD) enhanced V(O2), Φ(PSI) × PFD and the ratio of oxidized P700 to total P700 [(P700+)/(P700)total]. Φ(PSI) × PFD continued to increase even after the saturation of V(O2) against PFD. These results suggested that the electrons not used for the major electron sink, photosynthetic carbon reduction-cycle, did turnover in PSI, that is, CEF-PSI functioned at a higher PFD. High-light treatments did not affect the activity of CEF-PSI and increased (P700+)/(P700)total in the lower PFDs, compared to non-treated leaves. The activity of CEF-PSI depends on the amount of oxidized PQ. Photoinhibition of PSII suppressed electron influx from PSII to photosynthetic linear electron transport. The enhanced (P700+)/(P700)total suggested the increase in the ratio of oxidized plastoquinone (PQ) to total PQ, which supported the activity of CEF-PSI in the photoinhibited leaves.
Bioconcentration of LAS: Experimental Determination and Extrapolation to Environmental Mixtures

Linear alkylbenzenesulfonate (LAS) is the most widely used synthetic surfactant. Environmental risk assessment of LAS requires quantitative information on the bioconcentration properties which, as yet, are unavailable. Here, we present compound- and isomer-specific bioconcentration data for n-(p-sulfophenyl)alkanes, the constituents of LAS, determined in flow-through experiments. BCF values ranged between 2 and 1000 L kg-1. We derived bioconcentration−hydrophobicity relationships and observed that bioconcentration factors as well as uptake rate constants increase with increasing log KOW (estimated) while the elimination rate constants do not vary with log KOW. In an attempt to account for the variability of the composition of LAS mixtures, we found the average length of the alkyl chain of the LAS mixture unsuitable for estimation of the bioconcentration potential. In contrast, an estimation based on the composition of the mixture of LAS and the bioconcentration factors of the individual constituents overp.
Precision nutrient gradients. A component for optimal production.

Abstract Crop production, equivalent or exceeding any that has been attained or predicted, is possible from the sandy soils of peninsular Florida. However, extreme variability occurs from season to season, from field to field, and even within fields. Well managed field corn in Florida has averaged 50–70 bu/A, while maximum yields with irrigation have rarely exceeded 125 bu/A. Production of fresh market tomatoes, which in Florida have an annual value of 100 million dollars, varies from failure to 25 tons/A using the common cultural procedures. By utilizing a precision production system, consistent yields of 45 to 50 tons/A of fresh market tomatoes as well as 160–180 bu/A of field corn have been obtained. Combinations of controllable and non‐controllable factors with nutrition as a key component have been evaluated and selected as an approach to attain optimal production.
Kinetic studies of 1-methyl-2-thiourea with superoxide coordinated to cobalt(III)

At [H + ] = 0.04 mol dm -3 , µ = 0.25 mol dm -3 (NaClO 4), T = 31.0 ± 1.0 o C and λ = 670 nm, the bridging superoxide in [(NH 3)5Co(O 2)Co(NH 3)5]Cl 5.H 2O, herein refer to as Co(O 2)Co 5+ , quantitatively oxidizes 1-methyl-2-thiourea (MTU) to the corresponding urea derivative, itself being reduced to molecular oxygen and Co(II) in aqu eous perchloric acid. The reaction obeys the empirical rlaw: -d[Co(O 2)Co 5+ ]/dt = k 2[Co(O 2)Co 5+ ][MTU] with k 2 = (2.65 ± 0.15) x 10 -2 dm 3 mol -1 s -1 . The rate of the reaction increased with increase in ionic strength of reaction medium. There is no evidence for the forma tion of an intermediate complex of significant stab ility and free radicals are not detected in the reaction. Added an ions catalyzed the reaction. Based on the experimen tal data obtained, the outer-sphere mechanism is proposed.
Spectral characteristics of atmospheric pressure and electric field variations under severe weather conditions at high latitudes

Abstract. The time-dependent relationships between atmospheric parameters (electric field, positive and negative conductivity, variations of atmospheric pressure) and different meteorological phenomena (rain, fogs, snowstorms, thunderstorms) were investigated through spectral analysis. These parameters were measured with help of a high-latitude computer-aided complex installed at Apatity (66.5 N, 33.4 E). The complex consists of three spaced microbarographs for measurements of atmospheric pressure variations in the range of periods from 1 s to 40 min, an instrument measuring the vertical component of the electric field, and instrument used for measurements of air conductivity and surface ozone. A computer-aided data-gathering system makes it possible to obtain information in the frequency range between 1 and 0.0001 Hz. The time-dependent frequency analysis showed that the spectral characteristics of both electric field and atmospheric pressure variations changed synchronously during severe weather conditions.
Stability and antioxidative properties of acylated anthocyanins in three cultivars of red cabbage (Brassica oleracea L. var. capitata L. f. rubra)

BACKGROUND: Red cabbage is rich in acylated anthocyanins. The aim of the experiment has been to determine the stability of anthocyanins in extracts of red cabbage cultivars and examine their antioxidative properties. The (high-performance liquid chromatographic) HPLC profile of anthocyanins characteristic of each red cabbage cultivar has also been determined. RESULTS: We have used three red cabbage cultivars: cv. Koda, Haco POL and Kissendrup SWE. The HPLC assays enabled us to distinguish nine anthocyanin compounds, which were all classified as cyanidin derivatives. These compounds occurred in different proportions in the three culitvars of red cabbage. The differences were observed in the degradation index of anthocyanins in extracts from the red cabbage cultivars examined, both stored at + 2 °C and frozen. The highest trolox equivalent antioxidant capacity (TEAC) was attained for anthocyanins from cv. Haco POL red cabbage, whereas the lowest value was determined for cv. Koda. CONCLUSION: There were differences in the stability and antioxidative properties of anthocyanin compounds in red cabbage extracts among the cultivars evaluated (Koda, Haco POL and Kissendrup SWE). The highest stability and strongest antioxidative properties were assigned to anthocyanins in extracts from cv. Haco POL. The HPLC profiles imply differences in proportions of anthocyanin compounds present in the three red cabbage cultivars. Copyright © 2009 Society of Chemical Industry
Effect of x-rays and γ-rays on synthetic polymers in aqueous solution

A study has been made of the effect of ionizing radiation (x- and γ-rays) on aqueous solution of the following vinyl polymers: polymethacrylic acid, polyacrylic acid, polyacrylamide, polystyrene sulfonate, polyvinylpyrrolidone, and polyvinyl alcohol. In dilute solutions (<0.3% for the samples of polymer used) all the polymers are degraded by main chain fracture although in some cases dissolved oxygen has to be present. In others, degradation occurs in carefully deoxygenated solution but is increased by the presence of oxygen. The breakdown of polystyrene sulfonate is independent of oxygen. At higher concentration, crosslinking becomes the dominant action for all the polymers studied with the exception of polymethacrylic acid and ionized polyacrylic acid, which degrade at all concentrations. The dose of radiation necessary to produce a gel has been studied as a function of concentration and passes through a minimum. No gel formation occurs below a minimum polymer concentration of about 0.4%. The results cannot be explained on the basis that indirect action by the free radicals formed in the water leads to degradation while direct energy uptake by the polymer itself produces crosslinking. Other possible mechanisms are examined. The manner by which added substances reduce the effectiveness of irradiation (i.e., protect) is discussed briefly.
Multiadsorption and Coadsorption of Hydrogen on Model Conjugated Systems

Hydrogen interaction with conjugated aromatic molecular systems is analyzed with high level ab initio electronic structure methodology. The adsorption of hydrogen molecules on aromatic systems ranging from a single ring to double ring systems including fused and bridged molecules is investigated. We propose several functionalization schemes of the conjugated system to increase hydrogen intake. These functionalizations consist of using an asymmetrical conjugation skeleton as inherently present for the azulene molecule and the introduction of B−N heteroatom pairs as doping sites in the conjugation ring. We have also tested the possibility of involving more than a single interaction site within the same molecule by using a molecule involving several rings as the triptycene and several derived functionalized molecules. These computational studies provide insight on the interaction of hydrogen with conjugated molecular species. This insight can be utilized for designing materials such as metal organic framewor.
Enlarging the reactive cone of acceptance by exciting the C–H bond in the O(3P) + CHD3 reaction

The effects of the CH stretching vibration of methane on the O(3P) + CHD3 reaction are elucidated in a crossed-beam imaging experiment. For the H-atom abstraction channel, the ground state reaction leads mainly to the vibrational ground states of products, OH(v = 0) + CD3(v = 0). When the reactant CHD3 is prepared with one-quantum excitation of CH stretching vibration (v1 = 1), more than 90% of OH coproducts that formed concomitantly with the CD3(v = 0) product are in v = 1. Significant vibrational enhancement in the reaction rate is observed, and the product angular distribution shifts from a backward-dominance in O(3P) + CHD3(v = 0) to a sideways-peaking upon CH stretching excitation. As to the D-atom abstraction channel, the C–H bond excitation, despite being conserved in the CHD2 product, unexpectedly hinders the overall reactivity of the unexcited C–D bond. We interpret the experimental findings as the result of enlarging the reactive cone of acceptance in abstracting the H atom at the expense of the cone for the D-atom transfer channel.
SOLUBLE POLYMERIC HYDROXY‐ALUMINIUM IONS IN ACID SOILS

Summary Solution concentrations of total Al and of mononuclear Al ions were determined as a function of pH for two acid soils. Polynuclear hydroxy-Al was taken as the difference between total and mononuclear Al. Salt concentration at 1 : 5 soil: solution ratio was varied from 0·008 to 1·o equiv/l, for CaCl2, KCl, and NH4OAc at pH 4·8. Polynuclear hydroxy-Al concentrations increased with electrolyte concentration and the valency of the desorbing cation, and rose to 0·2 mM (equivalent to 3 meq/kg soil) in unbuffered salt suspensions, and to 1·0 mM in NH4OAc at pH 4·8. Polynuclear hydroxy-Al thus behaves like a normal exchangeable cation. I.0M NH4OAc released much more total A1 from some of the more acid samples than might have been expected from its pH of 4·8.
Role of youth in the Election of National Assembly 2013 (Case study of NA-48 & NA-49)

This study is aimed to examine the role of youth in National Assembly Elections-2013 in Islamabad. After May,11, 2013 General Elections a Elections commission of Pakistan reported that due to involvement of youth the huge turnout in the elections first time in the Pakistanâ’s history. This study also examines this claim and analyzes different factors due to which young people are more involved in political process. It addresses different mobilization trends of political parties create interest among youth; their attitude towards the political institutions; their perception about the effectiveness of political parties and politicians; and their need to have a platform for their political ideology. This study also examines whether Socio-political culture of politics in Pakistan is responsible in shaping young peoples’ values and views on politics. Furthermore, it also focused the uses of media and Specially social media among the youth for campaigns by different political parties. It is also highlighted in the research that youth is seems frustrate before elections-2013. This descriptive study is qualitative in nature. This study collected a sample of 50 youth from educational institutions as well as from kachi abadis of Islamabad. The findings reveal that young people were frustrate due to traditional politics in Pakistan, lack of political education and political socialization. This study finds out that young people are aware of political scenario and they do take interest in political talk shows in the media but this awareness and interest does not always translate into formal or conventional engagement with political party structures through membership etc. The conclusion that new mobilization trends specially social media attract the young people towards National Assembly Elections and increasing the political interest which also leads towards higher voter turnout in the General elections-2013.
Water solubility of metals in coarse PM and PM2.5 in typical urban environment in Hong Kong

Abstract An investigation of abundance and solubility of metals in size–segregated particulate matter (PM) was conducted at a typical urban site during the winter between late 2011 and early 2012 in Kowloon Tong, Hong Kong. The samples were extracted by both strong acid and water, and fourteen elements including Al, Ca, Cd, Cr, Co, Cu, Fe, Pb, Mg, Mn, Mo, Ni, V, and Zn were analyzed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP–OES) and Inductively Coupled Plasma Mass Spectrometry (ICP–MS). The metals in PM showed distinctly different profiles of their distribution between coarse particles (2.5 μm dp 2.5 ( dp 2.5 were higher than 10 while Cd, Pb, Zn, Mn and Cu were far above 100; whereas for coarse particles, the CEFs of most elements were lower than 10, except for Cd being higher than 100. Water and acid extractable fractions of coarse PM and PM 2.5 were analyzed and compared to investigate the transition metals solubility. The water extractable fraction was found to be present mainly in the fine particles, whereas more of the coarse fraction mass remained as insoluble fraction. The results from this study demonstrated large variation of water solubility of metals in urban aerosols in different size fractions and highlighted solubility as an important metric for considering the relation between metals and adverse health effects in epidemiological and toxicological studies.
Highly efficient and bending durable perovskite solar cells: toward a wearable power source

Perovskite solar cells are promising candidates for realizing an efficient, flexible, and lightweight energy supply system for wearable electronic devices. For flexible perovskite solar cells, achieving high power conversion efficiency (PCE) while using a low-temperature technology for the fabrication of a compact charge collection layer is a critical issue. Herein, we report on a flexible perovskite solar cell exhibiting 12.2% PCE as a result of the employment of an annealing-free, 20 nm thick, amorphous, compact TiOx layer deposited by atomic layer deposition. The excellent performance of the cell was attributed to fast electron transport, verified by time-resolved photoluminescence and impedance studies. The PCE remained the same down to 0.4 sun illumination, as well as to a 45° tilt to incident light. Mechanical bending of the devices worsened device performance by only 7% when a bending radius of 1 mm was used. The devices maintained 95% of the initial PCE after 1000 bending cycles for a bending radius of 10 mm. Degradation of the device performance by the bending was the result of crack formation from the transparent conducting oxide layer, demonstrating the potential of the low-temperature-processed TiOx layer to achieve more efficient and bendable perovskite solar cells, which becomes closer to a practical wearable power source.
Errors of Deixis Usage in French Narrative Texts

Several previous studies in foreign language learning have shown that obstacles and difficulties encountered by learners cause the production of language errors, including errors in the use of deixis. This study aims to investigate the use of deixis in students' French narrative texts and the most frequent errors in the use of deixis. This study was conducted using a qualitative descriptive research method. Thirty students from the Department of French Language Education, Universitas Pendidikan Indonesia of the 2019/2020 academic year were involved as participants. The choice of these participants was assured on the technique of purposive sampling, in this case, those who had passed the course of Production Écrite 4 (level A2 of CEFR). The data were narrative texts produced by the participants which were analyzed using the theory of error analysis based on the category of surface strategy (Dulay, Burt, & Krashen, 1982) and the theory of deixis (Levinson, 1983). The findings show that there were 138 deixis errors. The most dominant deixis error was the type of misformation (78%), especially on the use of temporal deixis. This is because most of the participants cannot determine which forms of tense correspond to the context of sentences. This study is expected to enrich the knowledge of pragmatic studies and the theory of language error analysis.