Miracle-dz/UniFAR-FTUs huggingface dataset:
Humidity-controlled mesostructuration in CTAB-templated silica thin film processing. The existence of a modulable steady state

A study is presented of the self-assembly process that takes place during CTAB-templated silica film formation through in situ SAXS, interferometry and water titration investigations during evaporation associated with dip coating under various conditions. This work shows that the quantity of water present in the film when the mesostructuration takes place depends on the relative humidity (RH) during deposition. Indeed, the system contains considerable quantities of water at high RH, while it loses water at low RH. The water content is demonstrated to be a critical parameter, as poorly ordered, 2D-hexagonal or 3D-cubic final structures are obtained, depending on the RH, in agreement with the general physico-chemical laws of CTAB mesophases. Furthermore, changing the RH or the solvent vapour pressure just after evaporation induces a film composition change and a potential mesostructure modification, evidencing a modulable steady state, during which the mesostructure can be modified by external influences. The present study pinpoints the role of processing conditions that are often considered secondary to chemical conditions. The conclusions of this study into the CTAB–TEOS system are also relevant to other surfactant-templated systems which undergo evaporation-controlled self-assembly.
Solvent Suppression Using Selective Echo Dephasing

Many types of NMR experiments have benefited from the Selective suppression can be achieved with MEGA in any sequence which forms a spin or stimulated echo. The subject significant advances in B0 gradient technology which have taken place over the past decade (1–4). In NMR spectrosof this Communication is limited to a simple spin-echo implementation of MEGA (Fig. 1a), which is compared with copy, B0 gradients can eliminate the need for phase cycling to select coherence pathways (5–15) and to achieve highsimilar implementations of excitation sculpting (Fig. 1b) and WATERGATE (Fig. 1c). quality water suppression (16–31). Gradient-enhanced water suppression methods can generally be classified into two MEGA can be understood using the same formalism that categories: (1) frequency-selective excitation followed by dephasing (spoiling) with gradient pulses (16–23), and (2) frequency-selective refocusing flanked by gradient pulses which dephase unwanted (nonrefocused) transverse magnetization (24–31). In the latter category, a technique known as excitation sculpting (31) offers the advantage that the transverse magnetization is returned to its original position, scaled by the square of the probability of spin inversion. This frequency-dependent inversion is determined by the choice of refocusing pulse S, which is applied an even number of times to eliminate phase distortions in the acquired even echo. S can be any sequence of RF pulses of any kind (31), although S is usually a composite sequence consisting of selective and nonselective 1807 pulses (32–36). Excitation sculpting also has the advantage of being less sensitive to flip-angle errors than the related technique known as WATERGATE (26, 27). As with any multiecho sequence, the minimum time (TE) required to execute excitation sculpting is limited by the time needed to apply at least two S sequences. In other words, the spins of interest (i.e., peaks outside the suppression band) must experience at least two refocusing pulses which may require a nonnegligible duration in certain applications. In practice, this situation arises in S sequences that employ composite, adiabatic, or spatially selective refocusing pulses which are longer than conventional (square) pulses. In this Communication, we describe a frequencyselective suppression method called MEGA (37) which offers many of the desirable features of excitation sculpting, with the additional advantage that the signals outside the suppression band are refocused with a single pulse (i.e., the signals of interest are refocused with a single echo). FIG. 1. The RF pulses and gradient waveforms are illustrated for MEGA (a), excitation sculpting (b), and WATERGATE (c) as implemented in a spin-echo sequence. § To whom correspondence should be addressed.
Effect of Plant Leaf Positions on Some Micronutrients, Anti-nutrients and Toxic Substances in Telfairia occidentalis at the Vegetative Phase

Pot experiment was conducted to determine the effect of leaf positions on the concentrations of some phytotoxins (cyanide, nitrate, soluble and total oxalates), micronutrients namely; vitamin C, β-carotene (provitamin A) and mineral elements (Fe, Mg, Cu, Zn, Ca Na and K) at vegetative phase of Telfairia occidentalis grown in nitrogen and non – nitrogen treated soil. The leaves of Telfairia occidentalis were harvested and analysed at three different leaf locations, namely; basal, middle and upper positions. The result obtained showed that no significant differences was observed in the cyanide concentration between basal and middle leaves and between middle and upper leaves, however, basal leaves had significant (p< 0.05) higher concentration of cyanide than upper leaves irrespective of soil nitrogen levels. The concentrations of nitrate and β-carotene in control and nitrogen fertilized Telfairia occidentalis were significantly (p<0.05) highest in upper, followed by middle and lowest in the basal leaf position. The soluble and total oxalates content in Telfairia occidentalis were significantly (p<0.05) higher in the basal and middle leaves than the upper leaves irrespective of soil nitrogen levels. While the vitamin C concentration in the vegetable was significantly elevated in basal leaves than the leaves obtain from middle and upper leaf locations. Analysis of mineral elements showed that Fe, Mg, Zn and Ca were concentrated more in the basal and middle leaves than the upper leaves while the K concentration was significantly (p<0.05) higher in the middle and upper leaves than the basal leaves in control and nitrogen treated Telfairia occidentalis. The results conclude that concentrations of most
Measurement and correlation of the adsorption equilibria of refrigerant vapors on activated carbon

Adsorption equilibrium data have been measured for four refrigerant vapors (R-113, R-11, R-318, and R-22) on BPL activated carbon at three temperatures over a wide range of partial pressures using an automated isotherm apparatus. Special emphasis is placed on the design and operation of the apparatus to ensure the quality of these data. Isotherm data for each refrigerant vapor are analyzed for correct Henry's law behavior and correlated using three- and four-parameter functions with specified temperature dependencies. The functions employed in this study include (1) the Langmuir equation, (2) the Dubinin-Astakhov equation, (3) the virial equation, and (4) the modified Antoine equation. The Dubinin-Astakhov equation provides the best (or very comparable) fits, based on the variance, for R-113, R-11, and R-318. However, the Dubinin-Astakhov equation does not correctly describe the behavior of the R-22 data, resulting from its incorrect approach to Henry's law. Overall result show that, for adsorption of these refrigerants on BPL activated carbon, those correlations with exponents on the adsorbed-phase concentration terms greater than 1 generate the smallest variances.
Physiological Daily Inhalation Rates for Free-Living Individuals Aged 1 Month to 96 Years, Using Data from Doubly Labeled Water Measurements: A Proposal for Air Quality Criteria, Standard Calculations and Health Risk Assessment

ABSTRACT Reported disappearance rates of oral doses of doubly labeled water (2H2O and H2 18O) in urine, monitored by gas-isotope-ratio mass spectrometry for an aggregate period of over 30,000 days and completed with indirect calorimetry and nutritional balance measurements, have been used to determine physiological daily inhalation rates for 2210 individuals aged 3 weeks to 96 years. Rates in m3/kg-day for healthy normal-weight individuals (n = 1252) were higher by 6 to 21% compared to their overweight/obese counterparts (n = 679). Rates for healthy normal-weight males and females drop by about 66 to 75% within the course of a lifetime. Infants and children between the age of 3 weeks to less than 7 years inhale 1.6 to 4.3 times more air (0.395 ± 0.048 to 0.739 ± 0.071 m3/kg-day, mean ± S.D., n = 581) than adults aged 23 to 96 years (0.172 ± 0.037 to 0.247 ± 0.039 m3/kg-day, n = 388). The 99th percentile rate of 0.725 m3/kg-day based on measurements for boys aged 2.6 to less than 6 months is recommended for air quality criteria and standard calculation for non-carcinogenic compounds pertaining to individuals of any age or gender (normality confirmed using the Shapiro-Wilk test, p ≥ 0.05). This rate is 2.5-fold more protective than the daily inhalation estimate of 0.286 m3/kg-day published by the Federal Register in 1980 (i.e., 20 m3/day for a 70-kg adult). It ensures that very few newborns aged 1 month and younger, less than 1% of infants aged 2.6 to less than 6 months and of course no older individuals up to 96 years of age inhale more toxic chemicals than associated safe doses which are not anticipated to result in any adverse effects in humans, when air concentration reaches the resulting air quality criteria and standard values. This rate is also protective for underweight, overweight, and obese individuals. Finally, as far as newborns are concerned, a rate of 0.956 m3/kg-day based on the 99th percentile estimates is recommended for short-term criteria and standard calculations for toxic chemicals that yield adverse effects over instantaneous to short-term duration.
Determination of enantiomer compositions of propranolol enantiomers by chiral ionic liquid as a chiral selector and the UV-assisted spectrophotometric method

Many chiral selectors have been used for recognition of enantiomeric compounds but their synthesis involves time-consuming and expensive multistep-processes with almost not optically pure products. In this paper, 1-butyl-3-methylimidazolium (T-4)-bis[(αS)-α-(hydroxy-O) benzeneacetato-κO] borate, a chiral ionic liquid which can be easily synthesized, was first used as a chiral selector in solution. The enantiomer compositions of propranolol hydrochloride were determined by using this chiral selector and the spectrophotometric method. The data of UV spectra showed that S-propranolol hydrochloride could be recognized in the mixture of the enantiomers with a total concentration of 1.50 × 10−4 M.
Operation of a Y-Ba-Cu-O rf SQUID at 81 K

An rf superconducting quantum interference device (SQUID) has been made from bulk Y‐Ba‐Cu‐O. The device displays quantum interference effects and operates with useful signal levels up to 81 K. The SQUID is formed from a ring of Y‐Ba‐Cu‐O which is broken in the cryogenic environment and then recontacted. Estimates of the SQUID noise performance are given.
The Effect of Reading in Shaping Undergraduates‟ Academic Research To

 Abstract —Existing evidence has proved that reading is integral in academic writing process and served different purposes at various junctures of students’ writing journey. Yet, few empirical studies investigate the effect of reading in shaping topic selection and formulation. This study aims to explore the process of undergraduate researchers determined their research topic through several rounds of reading. A qualitative research method was adopted in this research and six sophomore students were interviewed respectively. Results suggest that the novel researchers perused assorted literature in the phase of topic selection, and they showed a proclivity on certain types of literature according to distinct topic selection principles. Academic journals, monologues, textbooks were chosen by participants. In the phase of topic formulation, reading literature journals helped them identify their possible topics’ academic significance and pervasive research method, through which they could locate a board research area, then monographs and books assisted them to apprehend relevant knowledge and to assess research method so that they could narrow down their key terms and research context and finally they could formulate an appropriate research topic. The alteration of reading materials was caused by their insufficient knowledge of their research. Pedagogical implications are also
An easy-to-fabricate low-temperature TiO2 electron collection layer for high efficiency planar heterojunction perovskite solar cells

Organometal trihalide perovskite solar cells arguably represent the most auspicious new photovoltaic technology so far, as they possess an astonishing combination of properties. The impressive and brisk advances achieved so far bring forth highly efficient and solution processable solar cells, holding great promise to grow into a mature technology that is ready to be embedded on a large scale. However, the vast majority of state-of-the-art perovskite solar cells contains a dense TiO2 electron collection layer that requires a high temperature treatment (>450 °C), which obstructs the road towards roll-to-roll processing on flexible foils that can withstand no more than ∼150 °C. Furthermore, this high temperature treatment leads to an overall increased energy payback time and cumulative energy demand for this emerging photovoltaic technology. Here we present the implementation of an alternative TiO2 layer formed from an easily prepared nanoparticle dispersion, with annealing needs well within reach of roll-to-roll processing, making this technology also appealing from the energy payback aspect. Chemical and morphological analysis allows to understand and optimize the processing conditions of the TiO2 layer, finally resulting in a maximum obtained efficiency of 13.6% for a planar heterojunction solar cell within an ITO/TiO2/CH3NH3PbI3-xClxpoly(3-hexylthiophene)/Ag architecture.
TRANSITION METAL COMPLEXES WITH EDDA-TYPE LIGANDS—A REVIEW

ABSTRACT The review summarizes the results of recent studies on edda-type metal complexes. It focuses on work published during the period 1984–2001. The metals include are Co, Cr, Cu, Ni, Zn, Mn, Sn, Fe, V, Rh, Pt, Ru, whereas edda-type represents ethylenediamine-N,N′-diacetate, ethylenediamine-N,N-di-acetate, N,N′-dimethylethylenediamine-N,N′-diacetate, N,N′-diethylethylenediamine-N,N′-diacetate, 1,2-cyclo-hexanediamine-N,N′-diacetate, N,N′-dimethyl-1,2-cyclohexanediamine-N,N′-diacetate, ethylenediamine-N,N′-di-3-propionate, N,N′-dimethylethylenediamine-N,N′-di-3-propionate, ethylenediamine-N,N′-di-S-α-propionate, N,N′-dimethyl-ethylenediamine-N,N′-di-α-propionate, 1,3-propanediamine-N,N′-diacetate (trimethylenediamine-N,N′-diacetate), 1,3-propanediamine-N,N′-di-3-propionate (trimethylenediamine-N,N′-di-3-propionate), N,N′-dimethylethylenediamine-N,N′-di-α-butyrate, N,N′-diethylethylenediamine-N,N′-di-α-butyrate, 1-diethylenetriamineacetate (8-amino-3,6-diazao-ctanoate), ethylenepropylenetriamineacetate (9-amino-3,6-diazaoc- tanoate), dipropylenetriamineacetate (10-amino-3,6-diazaoc-tanoate), N,N-bis(2-aminoethyl)glycinate, N,N-bis(3-aminopropyl)glycinate, N-(2-aminoethyl)-N-(3-aminopropyl)glycinate, N-(2-aminoethyl)iminodiacetate (N-(2-aminoethyl)-N-carboxymethylglycine), N-(3-aminopropyl)imino diacetate tetradentate ligands. This paper provides a review of these complexes including their syntheses and X-ray crystal structures, spectroscopic (IR, Raman, NMR, ESR, electronic absorption and CD) measurements, electrochemistry, kinetic and thermodynamic information, magnetic properties, hydrolysis phenomena as well as chromatographic studies.
QSPR modelling of the octanol/water partition coefficient of organometallic substances by optimal SMILES-based descriptors

Usually, QSPR is not used to model organometallic compounds. We have modeled the octanol/water partition coefficient for organometallic compounds of Na, K, Ca, Cu, Fe, Zn, Ni, As, and Hg by optimal descriptors calculated with simplified molecular input line entry system (SMILES) notations. The best model is characterized by the following statistics: n=54, r2=0.9807, s=0.677, F=2636 (training set); n=26, r2=0.9693, s=0.969, F=759 (test set). Empirical criteria for the definition of the applicability domain for these models are discussed.
Synthesis of uniformly distributed carbon nanotubes on a large area of Si substrates by thermal chemical vapor deposition

We have synthesized carbon nanotubes by thermal chemical vapor deposition of C2H2 on transition metal-coated silicon substrates. Multiwalled carbon nanotubes are uniformly synthesized on a large area of the plain Si substrates, different from previously reported porous Si substrates. It is observed that surface modification of transition metals deposited on substrates by either etching with dipping in a HF solution and/or NH3 pretreatment is a crucial step for the nanotube growth prior to the reaction of C2H2 gas. We will demonstrate that the diameters of carbon nanotubes can be controlled by applying the different transition metals.
Thermoacoustic Instabilities in a Ducted Premixed Flame: Reduced-Order Models and Control

The problem of combustion instabilities arising from the thermoacoustic interactions in a ducted premixed flame model is considered. Contrary to the conventionally used low-order models to describe such systems, a high dimensional model governed by a set of the acoustic equations coupled to the equations for flame dynamics is employed. The flame front is discretized into finite flame elements to assign internal degrees of freedom to the front and track its evolution. Model reduction schemes, namely proper orthogonal decomposition (POD) and balanced truncation, are used to reduce the size of this model. Compared to POD modes, balanced modes show superior input–output characteristics, in agreement with the full model. POD modes on the other hand capture the transient growth in the model while the balanced modes do not. Performance of POD modes is highly dependent on the snapshots used for their computation. A linear quadratic Gaussian (LQG) framework using the reduced-order model based on 16 balanced modes is formulated to control thermoacoustic instabilities in the linear model. The controllers thus obtained are then used on the nonlinear model. They successfully curtail limit cycle oscillations in the nonlinear plant and also avoid subcritical transition to instability.
Quantitative Analysis of Current–Voltage Characteristics of Semiconducting Nanowires: Decoupling of Contact Effects

A metal‐semiconductor‐metal (M‐S‐M) model for quantitative analysis of current–voltage (I–V) characteristics of semiconducting nanowires is described and applied to fit experimental I–V curves of Bi2S3 nanowire transistors. The I–V characteristics of semiconducting nanowires are found to depend sensitively on the contacts, in particular on the Schottky barrier height and contact area, and the M‐S‐M model is shown to be able to reproduce all experimentally observed I–V characteristics using only few fitting variables. A procedure for decoupling contact effects from that of the intrinsic parameters of the semiconducting nanowires, such as conductivity, carrier mobility and doping concentration is proposed, demonstrated using experimental I–V curves obtained from Bi2S3 nanowires and compared with the field‐effect based method.
Growth Kinetics of ZnO Nanorods : Capping-Dependent Mechanism and Other Interesting Features

Although the growth of nanocrystals has been investigated by several workers, investigations of the growth of 1-D nanostructures have been limited. We have investigated the growth kinetics of both uncapped and poly(vinyl pyrollidone) (PVP)-capped ZnO nanorods carefully by a combined use of transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS) which provide direct information on size and shape and compensate for the deficiency of each other. Values of average length and diameter of the ZnO nanorods obtained by TEM and SAXS are comparable. In the presence of the capping agent, the length of the nanorods grows faster while the diameter becomes narrower. The length distribution shows periodic changes in the width in the case of the uncapped nanorods, a feature absent in the case of the capped nanorods. In the absence of the capping agent, we observe the presence of small nanocrystals next to the nanorods after a lapse of time. The occurrence of small nanocrystals as well as the period.
Application of the beta PdH Decomposition for Characterization of Supported Palladium Catalysts

Temperature-programmed (palladium) hydride decomposition (TPHD) appeared to be a convenient method for characterization of supported palladium catalysts. Both the amount of hydrogen released from the catalyst and the temperature of hydride decomposition are sensitive diagnostic parameters towards determining the mean size and, especially, the size distribution of palladium particles. On the other hand, carbiding of Pd/SiO 2 catalysts hinders incorporation of hydrogen into Pd bulk. The rate of temperature increase during the temperature-programmed hydride decomposition experiments seems to be an important factor. Application of too steep temperature ramps (e.g. 20°C/min) leads to the results which are less informative than the results obtained for lower ramps because the TPHD components characteristic for hydride decompositions from differently sized Pd crystallites merge into a single feature.
A new spectrophotometric method for the determination of ferrous iron in the presence of ferric iron

A new spectrophotometric method for the determination of ferrous iron concentration in samples containing ferric iron is presented. This new method is a modification of the Muir o-phenanthroline ferrous iron determination method. The new method consists of the quantitative spectrophotometric determination of Fe(II) by o-phenanthroline, but in which the ferric iron is complexed with sodium fluoride to eliminate interferences. A critical experimental comparison between the Muir spectrophotometric method, the Kolthoff titrametric method and the new proposed method is presented. Whenever Fe(III) accounts for more than 50% of the total iron in a sample, the method of Muir overestimates Fe(II). The proposed method has a range of 1–10 μg ferrous iron. It is as insensitive to other metal ions as the original method of Muir and is insensitive to Fe(III) up to a point where Fe(III) might be as high as 95% total iron. The proposed method is suitable for Fe(II) determination in bacterial leaching systems, where Fe(II) might be as low as 1% of total iron.
Efferent Impulses in the Splanchnic Nerve

Summary. Efferent impulses were observed in the splanchnic nerve of the cat, sometimes continuous, sometimes synchronous with respiration or with the heart beats. During asphyxia the amplitude of the impulses increased greatly. If artificial respiration was resumed, the electric activity quickly diminished and for a while nearly disappeared. Oxygen want led to an increase in the potentials, and pure oxygen to a decrease. Both these effects disappeared after the elimination of the buffer nerves. Accumulation of carbon dioxide caused greater activity in the nerve before as well as after section of the sinus and vagodepressor nerves. Bleeding, or the injection of acetylcholine, led to a remarkable increase in the potentials, whereas adrenaline gave rise to a diminution or even the disappearance of the impulses. After denervation of the sinus and aorta mechanisms, the effect of adrenaline was very small at normal blood pressure but fairly great at low level. Section of the sinus and vagodepressor nerves greatly increased the electric activity of the splanchnic nerve. The results are interpreted as being due to reflex influence from the chemo- and pressoreceptors of the sinus- and aorta mechanisms and to a central effect from carbon dioxide accumulation.