Miracle-dz/UniFAR-FTUs huggingface dataset:
Characteristics of atomic absorption calibration curves with the transversely heated graphite furnace

Calibration curves with two quasi-linear sections (“double sloping”) were observed for the medium volatile elements, Cr and Cu, with the use of a SIMAA 6000 graphite furnace atomic absorption spectrometer under interrupted internal gas flow conditions. If a standard transversally heated graphite atomizer (THGA) tube was shortened by 0.5 mm at both of its ends, (i.e. the gaps were enlarged between graphite furnace housing and tube ends), a stronger declination of the calibration curves resulted. Elements with fairly high diffusion coefficients (>5.8 cm2 s−1) and with short appearance time of their transients (<0.6 s), such as Cr and Cu, have shown the most characteristic sensitivity drop towards higher concentrations. This anomalous feature could be eliminated in three different ways; (1) by applying end-capped THGA tubes, (2) using mini-flow (50 cm3 min−1) conditions during the atomization stage, and (3) by adding Pd–Mg chemical modifier. For the low volatile Mo and V, the calibration curves had no irregular shape. For Ag, Co, Cr, Cu, Mn and Ni, the mini-flow settings improved the linearity of the calibration curves and extended the upper limit of the linear calibration range by a factor of 1.5–2.0. The irregular characteristic of the analytical curves was interpreted as an increased vapour loss at higher analyte concentrations through the opened ends of the standard THGA tubes. This vapour loss was associated with the significantly diverse expulsion velocities of atoms, caused by the difference in temperature and concentration gradients, when evaporating amounts of analytes with more than one order of magnitude difference.
Comparison of pilot and industrial scale atmospheric pressure glow discharge systems including a novel electro-acoustic technique for process monitoring

A comparison of a pilot and industrial scale atmospheric pressure polymer processing plasma system has been carried out using process-monitoring diagnostic tools during treatment of amorphous polyethylene terephthalate. These systems have been compared using optical emission spectroscopy (OES), photodiode (PD) analysis and multi-variate analysis of the applied electrical and emitted electro-acoustic signals to facilitate scale up operations from the pilot to the industrial scale system. The voltage, current, electro-acoustic intensity and frequency of the plasma systems were found to change systematically with an increase in applied plasma power and addition of oxygen (O2) into a helium (He) plasma. The plasma drive frequency was pulled by the plasma reactance from approximately 26 to 16 kHz on the pilot system and from approximately 36 to 32 kHz on the industrial system, for an increase in applied plasma power and addition of O2. The OES analysis revealed a number of peaks associated with nitrogen (N2) species between 250 and 450 nm due to the presence of air within the He plasma. Temporally resolved analysis of the discharge emission carried out using a PD showed an increase in the number of discharge events per power cycle with an increase in power and a decrease in emission intensity for addition of O2 into the He plasma for both the pilot and industrial scale systems. Using these diagnostic tools both plasma stability and run to run variations were assessed. A visual analysis of the 1.2 m wide plasma was also carried out where a more homogeneous plasma was observed at higher powers.
Stacking disorders in zeolites and open-frameworks – structure elucidation and analysis by electron crystallography and X-ray diffraction

Abstract Intergrowth and stacking disorders are often found in minerals and synthetic zeolites and inorganic open-frameworks. Structure elucidation of stacking disorders in these materials have been difficult and structure solution of stacking disorders in unknown zeolites and open-frameworks has been challenging. There exist no standard methods for structure analysis of such disordered materials. In this review we present various stacking disorders and intergrowth in a number of representative zeolite families containing stacking disorders. These include zeolite beta, SSZ-26/SSZ-33, ITQ-39, ABC-6, ZSM-48, SSZ-31, UTD-1, faujasite FAU/EMT, pentasil ZSM-5/ZSM-11, ITQ-13/ITQ-34, ITQ-22/ITQ-38 etc. Stacking disorders in open-frameworks containing mixed coordinations, including titanosilicates ETS-10 and ETS-4, and the silicogermanate SU-JU-14 are also described. Various crystallographic methods used for solving disordered structures are summarized. The methods include powder X-ray diffraction (PXRD), electron diffraction, high resolution transmission electron microscopy (HRTEM), and single-crystal X-ray diffraction. Examples of model building combined with simulations of PXRD and single crystal X-ray diffraction to verify the structure models are given.
Harmonic inversion of time signals and its applications

New methods of high resolution spectral analysis of short time signals are presented. These methods utilize the filter-diagonalization approach of Wall and Neuhauser [J. Chem. Phys. 102, 8011 (1995)] that extracts the complex frequencies ωk and amplitudes dk from a signal C(t)=∑kdke−itωk in a small frequency interval by recasting the harmonic inversion problem as the one of a small matrix diagonalization. The present methods are rigorously adapted to the conventional case of the signal available on a sparse equidistant time grid and use a more efficient boxlike filter. Various applications are discussed, such as iterative diagonalization of large Hamiltonian matrices for calculating bound and resonance states, scattering calculations in the presence of narrow resonances, etc. For the scattering problem the harmonic inversion is directly applied to the signal cn=(χf,Tn(Ĥ)χi), generated by the dynamical system governed by a modified Chebyshev recursion, avoiding the usual recasting the problem to the time d.
Two‐region model for hydrogen trapping in and release from graphite

A new model has been developed for hydrogen retention and trapping in and release from graphite. Two different regions in the graphite with different hydrogen transport and trapping behaviors are distinguished, the bulk region within, and the surface region on graphite crystallites. The model incorporates new experimental results related to atom diffusion and recombination on inner surfaces. Recombination is explained from a fundamental viewpoint by linking it to diffusion using a classical expression. The model is applied to a number of reemission and thermal desorption experiments, in particular, the reemission of hydrogen atoms during irradiation with energetic hydrogen ions and the formation of HD during irradiation with H+ and D+ or during thermal desorption of graphite that was preimplanted with H+ and D+ ions with different energies.
Fourier transform infrared spectroscopy of molecular interactions of heptafluoro-1-butanol or 1-butanol in supercritical carbon dioxide and supercritical ethane

Fourier transform infrared (FT-IR) spectroscopy was used to measure the degree of intermolecular hydrogen bonding for 2,2,3,3,4,4,4-heptafluoro-1-butanol-d and 1-butanol-d in supercritical carbon dioxide and supercritical ethane solvents. Supercritical binary solutions containing up to 0.10 mol fraction alcohol were examined under conditions ranging from 200 to 400 bar at 40{degree}C. In these fluids, an equilibrium appears to be established between the free non-hydrogen-bonded monomer and various hydrogen-bonded species. Aggregation numbers of these alcohols in carbon dioxide were in the range of 3.4-4.4 molecules per aggregate. The aggregate size in CO{sub 2} was, within experimental error, the same as found for supercritical ethane. Solute-solvent interactions were described using a semiempirical dielectric continuum model (Kirkwood-Bauer-Magat). The spectral evolution of a particular vibrational mode provided molecular level detail on the transition from a gas- to liquidlike solvation environment as the density of the supercritical fluid solvent was increased. The high solubility of the fluorinated alcohol in low dielectric constant fluids such as CO{sub 2} is primarily attributed to the weaker hydrogen-bonding energies of the fluorinated alcohol relative to those of the protonated alcohols. The contribution of fluorine repulsion to decreases in the attractive solute-solute interactions (i.e., steric hindrance) also acts to increase solubility inmore » low dielectric constant supercritical fluids. 45 refs., 13 figs., 2 tabs. « less
Effects of Sulfur Passivation on GaSb Metal–Oxide–Semiconductor Capacitors with Neutralized and Unneutralized (NH4)2S Solutions of Varied Concentrations

The effects of sulfur passivation on HfO2/GaSb MOS capacitors (MOSCAPs) with neutralized and unneutralized (NH4)2S solutions of varied concentrations were investigated. Treatment with neutralized (NH4)2S aqueous solutions reduced the interface trap density (Dit) by ∼23%, improving the effects of sulfur passivation and producing a smoother interface compared with that obtained by treatment with unneutralized (NH4)2S aqueous solutions. The improved performance of GaSb MOSCAPs is attributed to solution neutralization rather than the change in concentration because the distributions of Dit were similar for samples treated with (NH4)2S solutions of different concentrations.
A Universal Molecular Stent Method to Toughen any Hydrogels Based on Double Network Concept

Double‐network hydrogels (DN gels), despite their high water content, are the strongest and toughest soft and wet materials available. However, in conventional DN gels, which show extraordinarily high mechanical performance comparable to that of industrial rubbers, the first network must be a strong polyelectrolyte and this requirement greatly hinders the widespread application of these gels. A general method involving the use of a “molecular stent” for the synthesis of tough DN gels using any hydrophilic polymer as the first network is reported. This is the first reported method for the synthesis of tough DN gels using various neutral or weak polyelectrolyte hydrogels as the first network. This method helps extend the DN gel concept to various functional polymers and may increase the number of applications of hydrogels in various fields.
Virus crystallography and structural virology: a personal perspective

My first experiences with crystallography were as a graduate student at the University of Glasgow determining the structure of aromatic hydrocarbons using only primitive hand calculation techniques. I had my first experience using electronic computers as a post-doc in the lab of William Lipscomb in Minnesota. That gave me a good preparation for the structure determination of haemoglobin with Max Perutz in Cambridge. The discovery of the conserved globin fold had a major impact on my subsequent activities. It also provided the foundation for the development of the molecular replacement method and non-crystallographic symmetry electron density averaging that was essential for the structure determination of simple icosahedral viruses. The structure determination of a common cold virus was also a major stimulus for the study of more complex viruses and the development of the use of cryo-electron microscopy. This provided the basis for the investigation of lipid-enveloped viruses such as Sindbis virus and dengue virus. It also provided the technology for the study of bacteriophage DNA packaging motors and the mechanisms of infection by tailed and untailed phages.
Achieving Size Independent Hit-Rate in Single Particle Mass Spectrometry

Recent improvements in single particle mass spectrometers make it possible to optically detect, size, and characterize the compositions of individual particles with diameters larger than a micron and smaller than 100 nm. In these instruments, two stages of optical detection are used to generate a precisely timed trigger pulse that is used to fire the ion generation laser or lasers. However, experience shows that the wide particle size range results in significant differences in laser trigger timing between small and large particles. If not treated these differences produce an instrument with size dependent hit-rate. In this case the operator is forced to optimize the instrument for the desired size range, while contending with a significantly lower hit-rate for other particle sizes. This article presents an analysis of the phenomenon and demonstrates that the dependence of laser trigger timing on particle size stems from the differences in the particle position within the detection laser beam at the instant of detection. We demonstrate that it is possible to compensate for these differences by generating, for each particle, a laser trigger delay coefficient that is a function of particle's time of flight, i.e., its vacuum aerodynamic size. The study also shows that a single function can be used to eliminate the size bias for particles with a wide range of densities.
Sorption characteristics of peat from Brunei Darussalam for the removal of rhodamine B dye from aqueous solution: adsorption isotherms, thermodynamics, kinetics and regeneration studies

AbstractThis work reports the application of peat as cheap and effective adsorbent for the removal of rhodamine B dye (RhB) from aqueous solution. The effects of contact time, settling time and pH were studied to obtain the optimum conditions for adsorption studies. Optimum contact time was 4 h with 1 h settling time and ambient pH was used throughout the study. Adsorption isotherms, namely Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Redlich–Peterson and Sips, were employed in this study together with error functions to predict the most suitable isotherm model for the adsorption process. The Sips isotherm was found to be the best fit model. The maximum adsorption capacities (qmax) obtained for the adsorption at 298, 313, 324, 334 and 344 K are 162.87, 166.22, 172.45, 186.82 and 201.19 mg g−1, respectively. Thermodynamic parameters indicate that the adsorption was spontaneous, feasible and endothermic in nature. Pseudo second order kinetic model fitted well to the adsorption of RhB on peat. Regener.
Experimental study of high power mm-waves scattering by plasma turbulence in TCV plasmas

Understanding the propagation of high power mm-wave in plasmas is of tremendous importance in the route to fusion considering their extensive use in magnetically confined fusion devices. Mm-beams, launched from the outside of the vessel must propagate through plasma edge-turbulence before reaching their target region. Until recently, the effect of edge-turbulence on the beam propagation was neglected, but it has been estimated for ITER that it could lead to significant differences in the time-averaged and instantaneous beam profiles, leading to a loss of efficiency in their use. In this paper, we present first direct experimental measurements of high power beam after propagation in simple magnetized toroidal plasmas in TCV.
Evaluating the Curie-Weiss Temperature of a Magnetic System Composed of Nonequivalent Magnetic Ions in Terms of Spin Exchange Constants

E-mail: mike_whangbo@ncsu.eduReceived January 18, 2014, Accepted February 5, 2014Key Words : Nonequivalent magnetic ions, Curie-Weiss temperature, Mean field theory, Spin exchange pa-rameters, Density functional theory Magnetic properties of a system containing magnetic ionsare related to its electronic structure,
Monodisperse Organosilica Microcapsules with Functional Groups by Self-catalysis

On the basis of the self-catalytic sol-gel reaction of methyl trimethoxysilane (MTMS) and 3-aminopropyl trimethoxysilane (ATMS) at oil/water interface, monodisperse organosilica microcapsules with functional groups were prepared in one step at room temperature, without any surfactant or mediating reagent.
International Conference on Recent Trends in Engineering & Technology ICRTET-2013

Neck is robot part for human. The robotic platform of the neck bone was surrounded by muscles like steel spring the neck has a significant amount of movement and supports the weight of the head, but it is less protected than the rest of the neck, the neck can be vulnerable to injury and disorders that produce pain and restrict motion. In this work Density of Edge Length based Canny Edge Detection Algorithm has been proposed to pre processing of boundary detection of the MRI Scan Neck image. To find the correct boundary in noisy image of neck is still a difficult one. The proposed Canny Edge Detection algorithm has been used to detect the boundaries of neck image from the noisy image. The performance of proposed technique has been verified and validated with the standard medical values. The results show that the proposed technique performs well and produced very near to the optimal solution. This method is robust for all kinds of noisy images.
Important Factors Affecting Biosolid Nitrogen Mineralization in Soils

Abstract Biosolid nitrogen (N) ammonification, followed by nitrification in soil, produces nitrate ( ), which is not only a plant nutrient, but also a contaminant for ground water. Determining the most relevant factors influencing mineralization will help to manage N in biosolid-treated soils. Biosolid application rate, biosolid carbon (C):N ratio, biosolid organic N content, biosolid type, soil organic N content, soil pH, temperature, and time were compared among 12 published studies. Biosolid application rate, biosolid C:N ratio, and temperature significantly affected the mineralization rate and accounted up to 87% of the final model variability (R 2 = 79.1). Although the partial coefficients for soil pH and a dummy variable for biosolid were significant in the final model, their total contribution to the sum of partial coefficients was low (13%). There is insufficient evidence to conclude that soil organic N content and time contribute to biosolid N mineralization variability.
Overlapped moving windows followed by principal component analysis to extract information from chromatograms and application to classification analysis

Variable generation from chromatograms is conveniently accomplished using unsupervised rather than manual techniques. With unsupervised techniques, there is no need for selecting a few peaks for manual integration and valuable information is quickly and efficiently collected. The generation of variables can be performed by using either peak searching or moving window (MW) strategies. With a MW approach, the peaks are ignored and many variables, only part of them carrying information, are generated. Thus, variable generation by MWs should be followed by data compression to generate the variables to be further used for classification or quantitation purposes. In this work, unsupervised processing of chromatograms was performed by MWs followed by principal component analysis (MW-PCA). The principal components were selected and used as input variables for class prediction by linear discriminant analysis (LDA). Both simulated and real chromatograms were used to study the influence of both the window width and the degree of overlapping of consecutive windows on the quality of the predictions (estimated as the percentage of correctly classified chromatograms by leave-one-out). Hence, the quality of the variables generated by MW-PCA was inferred. For this purpose, a series of chromatograms containing a few peaks and belonging to four classes or categories were generated. Extra virgin olive oils of four pure cultivars were also used. In this case, a gas chromatograph provided with a flame ionization detector was used to obtain the chromatograms of fatty acid methyl esters. Windows within a wide range of moderate widths provided similar performances, and the quality of the predictions always increased with the degree of overlapping of consecutive windows. Thus, for MW-PCA variable generation, moderately wide and largely overlapped windows are recommended.
Anodic Stripping Voltammetry: Arsenic Determination in Ancient Bone Samples

Abstract A highly sensitive method for the determination of arsenic (As) content in ancient bone samples was studied using a gold tipped rotating disc electrode and differential pulse anodic stripping voltammetry. Factors affecting sensitivity and precision, including electrolyte concentration, deposition potential, deposition time, and rotation rate were investigated. Electroinactive As(V) was reduced to As(III) by HCl 30% w/v prior to electroanalytical measurements. For a deposition time of 120 sec, the lowest detection limit (LOD) for arsenic was 1.078 µg/L. Optimized working conditions are defined as a deposition potential of −1200 mV with a deposition time of 120 sec, 10 M HCl as the supporting electrolyte, and a rotation rate of 2000 rpm. Results of electroanalytial measurements in ancient bone samples are compared with those obtained from the hydride generation atomic absorption spectroscopy (HG‐FAAS) analysis. Analytical relevancy of the two methods was then compared with the aid of statistical data treatment.
Determination of trace levels of nitric oxide in aqueous solution

Nitric oxide at trace levels (< 10/sup -13/ M) in aqueous solution is determined by using a flow system to equilibrate the solution with a gas stream and measuring NO/sub g/ with a chemiluminescence detector. A standard p/sub NO/ prepared by dynamic dilution of gases is used to calibrate the detector and to test the system for adsorptive and artifact effects. NO signals are differentiated from interferents by criteria based on the gas/solution partition coefficient of NO, its low boiling point, or reversible formation of the Fe(NO)/sup 2 +/ complex. The precision of the technique at the greater than or equal to 10/sup -13/ M(NO)/sub aq/ level is approx. +- 3% and the accuracy is estimated to be +- 20%; a determination requires about 2 min. The versatility of the method and its applicability to environmental measurements are illustrated by relevant examples.
INFLUENCE OF MAGNESIUM ADDED TO DIET OF PULAWSKA BREED FATTENERS ON PHYSICAL AND CHEMICAL PROPERTIES OF MEAT

Magnesium is a macronutrient involved in numerous physiological and biochemical processes in an animal organism. This study aimed at evaluating the influence of Mg supplementation of feed for fatteners on physical, chemical and sensory properties of their meat. The experiment was conducted on 30 Pulawska breed fatteners divided into two groups: experimental and control. The former group was daily supplemented with 1 g MgCl 2 ⋅6H 2 O for 30 days before slaughter. After slaughter (when fatteners had gained 105 kg ± 0.4 kg of body weight), samples of ham muscle (musculus adductor femoris) were taken for determinations of the meat quality. Magnesium supplementation had a positive effect on pH1 and pH24 of meat. Decreased free water percentage, re-emission and green colour share, accompanied by an increase in the red colour proportion in ham meat, occurred owing to magnesium (these differences were important statistically). Another finding was a higher level of hematin in meat from the experimental animal group. As for the general chemical composition of meat from the experimental group, dry matter and glycogen content increased. No effect of magnesium supplementation was observed in the sensory quality assessment of meat. Magnesium added to feed caused slower decomposition of muscular glycogen, thus preventing a substantial decrease in the meat pH after slaughter. The meat of fatteners from the experimental group was characterized by superior technological indices.