Miracle-dz/UniFAR-FTUs huggingface dataset:
UV spectrophotometric studies of arsenic(III) and antimony(III) aqueous chemistry from 25 to 300°C

The aim of this study has been to provide a reliable set of experimentally based thermodynamic data which define the ionisation of arsenous and antimonous acids (i.e. H As02 and H3Sb03 ) and p-nitrophenol from 25 to 300°C at saturated vapour pressures. In addition, the stability and stoichiometry of the thioarsenite aqueous species have also been determined at ambient temperature. The main experimental method used in this study is high temperature fiow-through uv-vis spectroscopy. However, in order to be able to determine the stability and stoichiometry of the thioarsenite aqueous species, a new experimental set-up was designed and constructed which facilitated accurate measurements in hydrogen sulphide containing solutions. A mathematical treatment of the experimental data was developed and successfully applied. Dilute solutions of p-nitrophenol and its deprotonated equivalent exhibit well defined spectra throughout the visible and ultraviolet region which comprise a simple, ideal system with which to test and confirm the validity of our spectrophotometric methodology and mathematical data treatment. The ultraviolet spectra of dilute antimony and arsenic aqueous solutions have been measured from 25 to 300°C at the saturated vapour pressure. From these measurements, stability constants were obtained for the following reactions: for which pK1(arsenous acid) decreases from 9.25 to 7.11 over a temperature range from 25 to 300°C; for which pK1(antimonous acid) decreases from 11.82 to 9.88 over a temperature range from 25 to 300°C;
THE SHEPHERDS HOOK PHENOMENON PATTERN OF HAIR ROOTS A DEMONSTRATION OF COMPARATIVE BIOLECTROMAGNETISM BETWEEN HUMAN HAIRS AND MOUSE WHISKERS BY MEANS OF THE PHOTOELECTRIC EFFECT

In this manuscript, the phenomena herein reported have been observed in some of prior publications by this author. This manuscript is a compilation of cross-species similarities on the biomagnetic fields (BMFs) emitted by the human hair and mouse vibrissa follicles. The introduction of a novel optical microscopy technique designed to detect BMFs in plant and animal tissue has allowed researchers to publish interesting and unique findings. They range from hair follicles BMFs penetrating glass barriers to the biomagnetic effect on crystals accretion of fronted hair follicles. Both rodents (whiskers) and human (hair follicles) show similarities regarding spontaneous BMFs expressed as light rays with one sided greater BMF activity. The technique used as a base the iron staining property of Prussian Blue Stain (PBS) mixed with very fine iron particles 2000 nm in diameter (for magnetic attraction). For this manuscript, previously published images were re-reviewed and addressed as such in the manuscript. Both PBS mixed with the diamagnetic Potassium Ferrocyanide and PBS mixed with the paramagnetic Potassium Ferricyanide were alternatively chosen in those experiments. During evaporation, the hair shaft and follicle, due to their intrinsic diamagnetism, repels the crystals of diamagnetic PBS and attracts the paramagnetic ones. Experiments are presented consistently demonstrating a unique pattern observed of BMFs skewed towards or along one side of the human hair shaft and follicle of humans and rodent vibrissa whiskers. This is attributed to “The Photoelectric Effect” discovered in 1887 by the German physicist Heinrich Rudolf Hertz.
Comparative Analysis of Cellular Prion Detection by Mass‐Sensitive Immunosensors

We performed a comparative study of the de- tection of human cellular prions (PrP C ) with a quartz crystal microbalance (QCM) immunosensor using various antibodies against PrP C. The sensing layer was formed by immobilized antibodies on a surface of polyamidoamine dendrimers (PAMAM) of fourth generation (G4) with at- tached protein A. The sensitivity of detection depended on the kind of antibody used and the best detection limit was 0.8 nM. PrP C detection in 10 times diluted blood plasma revealed more complicated behavior of motional resistance, which is evidence on viscosity contribution. The sensor recovery was 82.2 %, suggesting certain matrix effects on prion detection.
Generation of thermodynamic data for organic liquid mixtures from molecular simulations

Fluctuation solution theory (FST) is employed to analyze results of molecular dynamics (MD) simulations of liquid mixtures. The objective is to generate parameters for macroscopic thermodynamic property models. Two benchmark systems, benzene–methyl acetate at 303.15 K and benzene–ethanol at 298.15 K, are used. MD simulations are performed in the isobaric–isothermal ensemble (NPT) at the respective temperatures and at a pressure of 1 atm. We use the CHARMM27 force field at different mixing ratios. We sample positions to determine the binary (between the centers-of-mass of molecules of a pair) radial distribution functions (RDFs). The RDFs are integrated to give the total correlation function integrals (TCFIs). Errors in TCFIs due to uncertainties in RDFs from simulation have been overcome by introducing a simple expression to reproduce the indirect interactions allowing reliable extrapolation to infinite distances. We compare the results of our computations with measured data on both systems studied. The results for activity coefficients agree to within experimental uncertainty.
The role of childhood sexual abuse, social support, and optimism in the development of posttraumatic stress disorder

Studies have shown that there are many variables often associated with the development of Posttraumatic Stress Disorder (PTSD), however many issues relating to the etiology of the disease are still unknown. Understanding the variables that are often linked with PTSD will help researchers and mental health professionals understand the disease and provide proper treatment. The purpose of this study was to examine the role childhood sexual abuse (CSA), social support, and a person's worldview (i.e., optimistic or pessimistic attitudes) had on PTSD. There were a total of 427 women, 162 of these women had experienced CSA and 265 had not experienced CSA. Participants were asked to fill out questionnaires that assessed PTSD symptoms, degree of social support, and worldview. A correlational-regressional approach was used to investigate the relationship between PTSD and the above-mentioned variables. It was predicted that there would be a significant positive relationship between severity of CSA and level of PTSD. It was also predicted that there would be a significant negative relationship between level of optimism and level of PTSD. Moreover, it was predicted that there would be a significant negative relationship between level of social support and level of
Proton-transfer-reaction mass spectrometry (PTR-MS): on-line monitoring of volatile organic compounds at volume mixing ratios of a few pptv

A system for on-line measurements of trace compounds in air with concentrations as low as a few pptv has been developed on the basis of proton transfer reactions. The sensitivity of this system is demonstrated by means of calibration data of benzene and data on the diurnal variation of C9-alkylbenzene and its 13C-isotope in ambient air. First on-line data on the concentrations of volatile organic compounds obtained during plane flights are presented.
Characterization of an Ambient Coarse Particle Concentrator Used for Human Exposure Studies: Aerosol Size Distributions, Chemical Composition, and Concentration Enrichment

The goals of the experiments described herein involve determining in real time the size, concentration enrichment, and chemical composition of coarse-mode (<2.5 μm) and fine-mode (>2.5 μm) particles within the nonconcentrated and concentrated flows of a coarse particle concentrator used for human exposure studies. The coarse particle concentrator was intended to concentrate ambient particles in the PM10–2.5 size range before sending them into a human exposure chamber. The aerodynamic size and chemical composition of particles in the upstream and downstream flows of the concentrator were monitored with an aerosol time-of-f1ight mass spectrometer (ATOFMS) for fixed time intervals over the course of three days. Based on the ATOFMS results, it was found that there was no change in the composition of the ten major particle types observed in the upstream and downstream flows of the concentrator under normal operating conditions. Furthermore, no new particle types were detected downstream that were not detected upstream of the concentrator. A characterization of the aerosol chemical composition and its dependence on sampling conditions is also discussed. Aerosol size distributions were measured with three aerodynamic particle-sizing (APS) instruments sampling simultaneously from different regions of the concentrator. The APS size distributions were used to scale ATOFMS data and measure the ambient concentration factors for the coarse particle concentrator and the exposure chamber. The average concentration factor (ratio of inlet number concentration to the outlet number concentration) for the particle concentrator was 60 + 17 for the 2.5–7.2 μm size range before dilution and transport to the exposure chamber. It was observed that not only were coarse particles being concentrated but fine (<2.5 μm) particles were being concentrated as well, with concentration factors ranging from 2–46 for aerodynamic particle sizes from 0.54–2.5 μm.
Oxidation of Lindane with Fe(II)-Activated Sodium Persulfate

Lindane or γ-hexachlorocyclohexane (γ-HCH) is a known carcinogen and a notoriously persistent organic pollutant in the environment. Reported herein is a study of lindane oxidation by persulfate (S2O82−) in aqueous solution (22 ± 1°C). Persulfate is quickly activated by ferrous iron, and produces highly potent sulfate radicals (SO4−·) with standard potential at 2.6 V. The rate of lindane oxidation is proportional to the concentration of persulfate, and when the ferrous iron to persulfate concentration ratio is less than 1, the reaction rate is also proportional to the ferrous iron concentration. The reaction rates were substantially higher when the solution pH was less than 1.5 or greater than 11. The final products are chloride and carbon dioxide, suggesting complete lindane oxidation. The reaction half-life of oxidation of 0.0172 mM lindane with 4.2 mM persulfate and 0.108 mM ferrous iron was approximately 27.18 h. Compared to the classical Fenton's reaction, persulfate has relatively longer lifetime in .
BASE-INDUCED RELEASE OF MOLECULES FROM HYDROGEN BONDING DIRECTED LAYER-BY-LAYER FILM *

On the basis of hydrogen bonding directed layer-by-layer (LbL) assembly we have fabricated two multilayer systems, poly(acrylic acid) bearing spironaphthoxazine (PAA-SO)/poly(4-vinylpyridine) and carboxyl-terminated polyether dendrimer (dendrimer-COOH)/poly(4-vinylpyridine). UV-Vis spectroscopy indicates that either PAA-SO or dendrimer-COOH can be released from the corresponding multilayer assemblies upon immerssion in a basic aqueous solution. Furthermore, the rate of molecule release can be controlled either by changing the pH value or by adjusting the layer structure.
Growth of Arrayed Nanorods and Nanowires of ZnO from Aqueous Solutions

A novel approach to the rational fabrication of smart and functional metal oxide particulate thin films and coatings is demonstrated on the growth of ZnO nanowires and oriented nanorod arrays. The synthesis involves a template‐less and surfactant‐free aqueous method, which enables the generation of, at large‐scale, low‐cost, and moderate temperatures, advanced metal oxide thin films with controlled complexity. The strategy consists of monitoring of the nucleation, growth, and aging processes by means of chemical and electrostatic control of the interfacial free energy. It enables the control of the size of nano‐, meso‐, and microcrystallites, their surface morphology, orientations onto various substrates, and crystal structure.
Laser doppler measurements of flow in freeboard of a fluidized bed

One of the factors which reduces combustion efficiency in a fluidized-bed combustor is the elutriation of fine coal particles from the freeboard above the bed surface. To our knowledge, data about the real local flow behavior of the two-phase flow in the freeboard are lacking in the literature. This paper concerns the measurement of the gas and the elutriated particle velocities in the freeboard of a cold fluidized bed using Laser Doppler Anemometry. A special electronic system has been devised to record simultaneously the gas and particle velocities and to indicate the size of the particles. In this paper the apparatus and some preliminary measurements are reported. The most significant observation is that the gas velocity profiles exhibit minima near the bed center and maxima near the walls.
The Effect of Type and Concentration of Nano-Particles on the Mass Transfer Coefficients: Experimental and Sherwood Number Correlating

Developments in the area of nano-fluids are ongoing specifically in the area of liquid-liquid extractions in different industries. In the present study, mass transfer coefficients have been obtained experimentally in a spray extraction column in the presence of different nano-particles to develop a new correlation for the prediction of the dispersed phase Sherwood number. The results have shown that the proposed correlation can estimate the experimental drop Sherwood number with high accuracy. Also, the conceptual effect of nano-particle hydrophobicity/hydrophilicity is quantified in correlation without which the experimental data could not be fitted with an acceptable accuracy.
Application of Preconcentration and Separation Techniques in Atomic Fluorescence Spectrometry

Abstract With 135 references, this review presents the recent application of various preconcentration and separation techniques in atomic fluorescence spectrometry for the sensitive determination and speciation of various elements and their species. It focuses on sample pretreatment, separation, and enrichment-related techniques, including liquid–liquid extraction, solid-phase (micro)extraction, microwave/ultrasound-assisted extraction, pressurized liquid extraction, as well as chemical vapor generation. In this review, the historical development and overview of these preconcentration and separation methodologies are briefly discussed, together with a comprehensive collection of application of these methods in combination with atomic fluorescence spectrometry for determination of ultratrace amounts of elements and their species in various sample matrices (liquids and solids).
Preparation of amidoximated polyester fiber and competitive adsorption of some heavy metal ions from aqueous solution onto this fiber

In this study, a fibrous adsorbent containing amidoxime groups was prepared by graft copolymerization of acrylonitrile (AN) onto poly(ethylene terephthalate) (PET) fibers using benzoyl peroxide (Bz2O2) as initiator in aqueous solution, and subsequent chemical modification of cyano groups by reaction with hydroxylamine hydrochloride in methanol. The grafted and modified fibers were characterized by FTIR, TGA, SEM, and XRD analysis. The crystallinity increased, but thermal stability decreased with grafting and amidoximation. The removal of Cu(II), Ni(II), Co(II), Pb(II), and Cd(II) ions from aqueous solution onto chelating fibers were studied using batch adsorption method. These properties were investigated under competitive conditions. The effects of the pH, contact time, and initial ion concentration on the removal percentage of ions were studied. The results show that the adsorption rate of metal ions followed the given order Co(II) > Pb(II) > Cd(II) > Ni(II) > Cu(II). The percentage removal of ions increased with initial ion concentration, shaking time, and pH of the medium. Total metal ion removal capacity was 49.75 mg/g fiber on amidoximated fiber. It was observed that amidoximated fibers can be regenerated by acid without losing their activity, and it is more selective for Pb(II) ions in the mixed solution of Pb-Cu-Ni–Co-Cd at pH 4. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of polysaccharides in different molecular weights from Ulva pertusa Kjellm （Chorophyta）

As molecular weight controls the biological activities of polysaccharides, screening the optimal molecular weight of polysaccharides is important in drug research and application. In this study, hydrogen peroxide was employed as oxidant, and temperature, reaction time, and concentration of polysaccharides and hydrogen peroxide were examined for their effects on the preparation of polysaccharides in different molecular weights from Ulva pertusa. Our experiment suggested that the optimal degradation concentrations for polysaccharides and hydrogen peroxide were 2.5% (w/v) and 8.0% (v/v), respectively. The range of degradation measured by relative viscosity was mainly controlled by temperature and time. Results revealed that 35℃ was the optimal temperature for obtaining low-degradation samples, and 50℃ was the most favorable temperature to accelerate the reaction to yield highly-degraded samples. Four samples in different molecular weights A, B, C and D were finally prepared. The controllability was evaluated by the relative standard deviation (RSD) of relative viscosity, and the peak molecular weights and the polydispersity indexes (Mw/Mn) of molecular weights were measured by high performance gel permeation chromatography (HPGPC).
Acoustic Wave Microsensors

Acoustic wave microsensors are being used for broader applications in chemical sensing and interfacial studies as more devices are invented and new sensor response mechanisms are elucidated. This report compares and contrasts the more commonly used acoustic wave devices and provide a current description of the physical origins of observed sensor responses in both gas- and liquid-phase studies. The types of waves and devices as well as information on operation and measurement methods, mass sensitivity, and detection are discussed. We focus primarily on thickness-shear mode (TSM), surface acoustic wave (SAW), flexural plate wave (FPW), and acoustic plate mode (APM) devices. 65 refs., 4 figs., 2 tabs.
Current Practice Of Gas Chromatography-Mass Spectrometry

Part 1 Principles and instrumentation of GC-MS: principles and instrumentation of GC-MS principles and applications of surface ionization in GC-MS. Part 2 Industrial and environmental applications: GC-MS in the petroleum industry analysis of dioxins and PCBs by quadrupole ion-trap GC-MS GC-MS analysis of chlorinated organic compounds principles, instrumentation and application of SPE-GC-MS and LC-GC-MS GC-MS in occupational and environmental health risk assesment with some applications related to environmental and biological monitoring of 1-nitopyrene application of SPME-GC-MS in quantitative bioanalysis. Part 3 Pharmaceutical and clinical applications: GC-MS of drugs in biological fluids after automated sample pre-treatment GC-MS analysis of anaesthetics and metabolites using multidimensional detection strategies GC-MS in clinical stable isotope studies - possibilities and limitations clinical steroid analysis by GC-MS GC-MS for selective screening for inborn errors of metabolism. Part 4 Toxicological and forensic applications: applications of GC-MS in clinical and forensic toxicology and doping control detection of drugs of abuse by GC-MS GC-MS analysis of explosives. Part 5 Food-related applications: GC-MS analysis of flavours and fragrances GC-MS analysis for residue analysis - some basic concepts applications of GC-MS in residue analysis of veterinary hormonal substances and endocrine disruptors identification of terpenes by GC-MS.
Linear-Time Safe-Alternating DFS and SCCs.

An alternating graph is a directed graph whose vertex set is partitioned into two classes, existential and universal. This forms the basic arena for a plethora of infinite duration two-player games where Player~$\square$ and~$\ocircle$ alternate in a turn-based sliding of a pebble along the arcs they control. We study alternating strongly-connectedness as a generalization of strongly-connectedness in directed graphs, aiming at providing a linear time decomposition and a sound structural graph characterization. For this a refined notion of alternating reachability is introduced: Player~$\square$ attempts to reach vertices without leaving a prescribed subset of the vertices, while Player~$\ocircle$ works against. This is named \emph{safe alternating reachability}. It is shown that every arena uniquely decomposes into safe alternating strongly-connected components where Player~$\square$ can visit each vertex within a given component infinitely often, without having to ever leave out the component itself. Our main result is a linear time algorithm for computing this alternating graph decomposition. Both the underlying graph structures and the algorithm generalize the classical decomposition of a directed graph into strongly-connected components. The algorithm builds on a linear time generalization of the depth-first search on alternation, taking inspiration from Tarjan 1972 machinery. Our theory has direct applications in solving well-known infinite duration pebble games faster. Dinneen and Khoussainov showed in 1999 that deciding a given Update Game costs $O(mn)$ time, where $n$ is the number of vertices and $m$ is that of arcs. We solve the task in $\Theta(m+n)$ linear~time. The complexity of Explicit McNaughton-M\"uller Games also improves from cubic to quadratic.
The Role of Edge Robotics As-a-Service in Monitoring COVID-19 Infection

Deep learning technology has been widely used in edge computing. However, pandemics like covid-19 require deep learning capabilities at mobile devices (detect respiratory rate using mobile robotics or conduct CT scan using a mobile scanner), which are severely constrained by the limited storage and computation resources at the device level. To solve this problem, we propose a three-tier architecture, including robot layers, edge layers, and cloud layers. We adopt this architecture to design a non-contact respiratory monitoring system to break down respiratory rate calculation tasks. Experimental results of respiratory rate monitoring show that the proposed approach in this paper significantly outperforms other approaches. It is supported by computation time costs with 2.26 ms per frame, 27.48 ms per frame, 0.78 seconds for convolution operation, similarity calculation, processing one-minute length respiratory signals, respectively. And the computation time costs of our three-tier architecture are less than that of edge+cloud architecture and cloud architecture. Moreover, we use our three-tire architecture for CT image diagnosis task decomposition. The evaluation of a CT image dataset of COVID-19 proves that our three-tire architecture is useful for resolving tasks on deep learning networks by edge equipment. There are broad application scenarios in smart hospitals in the future.
FIBER LOOP RING DOWN SPECTROSCOPY FOR TRACE CHEMICAL DETECTION

Fiber loop ring down (FLRD) spectroscopy is a technique that combines high sensitivity of cavity ring down spectroscopy and elasticity of fiber optic cables. FLRD is a time domain technique that measures optical losses of a light pulse in a fiber loop. In FLRD spectroscopy, detection of a sample is performed by measurement of leaking light at each round trip within an optical cavity. Intensity of leaking light has an exponential decay where it is reduced by absorption of sample and scattering of light. FLRD technique is utilized for characterization of different chemicals and sensing various physical properties such as pressure, temperature, refractive index etc. via remote control. Utilization of FLRD spectroscopy with the aim of trace gas detection has increased in recent years. Different FLRD systems are being improved with this aim in order to increase its sensitivity. Ultimate aim is to be able to perform trace detection at visible region where the chemical sensitivity is higher. Here we present an initial set-up that was designed at 1535 nm and its application on gas and liquid sample detection for trace chemical analysis.