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Radiological image analysis using machine learning has been extensively applied to enhance biopsy diagnosis accuracy and assist radiologists with precise cures. With improvements in the medical industry and its technology, computer-aided diagnosis (CAD) systems have been essential in detecting early cancer signs in patients that could not be observed physically, exclusive of introducing errors. CAD is a detection system that combines artificially intelligent techniques with image processing applications thru computer vision. Several manual procedures are reported in state of the art for cancer diagnosis. Still, they are costly, time-consuming and diagnose cancer in late stages such as CT scans, radiography, and MRI scan. In this research, numerous state-of-the-art approaches on multi-organs detection using clinical practices are evaluated, such as cancer, neurological, psychiatric, cardiovascular and abdominal imaging. Additionally, numerous sound approaches are clustered together and their results are assessed and compared on benchmark datasets. Standard metrics such as accuracy, sensitivity, specificity and false-positive rate are employed to check the validity of the current models reported in the literature. Finally, existing issues are highlighted and possible directions for future work are also suggested. [ABSTRACT FROM AUTHOR]

Music is ubiquitous in our everyday lives, and lyrics play an integral role when we listen to music. The complex relationships between lyrical content, its temporal evolution over the last decades, and genre-specific variations, however, are yet to be fully understood. In this work, we investigate the dynamics of English lyrics of Western, popular music over five decades and five genres, using a wide set of lyrics descriptors, including lyrical complexity, structure, emotion, and popularity. We find that pop music lyrics have become simpler and easier to comprehend over time: not only does the lexical complexity of lyrics decrease (for instance, captured by vocabulary richness or readability of lyrics), but we also observe that the structural complexity (for instance, the repetitiveness of lyrics) has decreased. In addition, we confirm previous analyses showing that the emotion described by lyrics has become more negative and that lyrics have become more personal over the last five decades. Finally, a comparison of lyrics view counts and listening counts shows that when it comes to the listeners' interest in lyrics, for instance, rock fans mostly enjoy lyrics from older songs; country fans are more interested in new songs' lyrics. [ABSTRACT FROM AUTHOR]

Background: Due to the increasing usage of plastic, microplastics or plastic particles with a length of 1 to 5 mm are omnipresent in the environment, including freshwater, agricultural soil and seas. The majority of plastic trash is made up of microplastic debris, which has lately started to threaten ecosystems. This calls for immediate management and analysis to ensure the traceability of microplastics in the environment. The polymeric variety, irregular shape and microscopic size of microplastics make it difficult to quantify their presence in the environment. In this review, the analytical techniques for evaluating microplastics are discussed. The techniques included Fourier transform infrared spectroscopy, Raman spectroscopy, laser diffraction particle, thermal analysis, scanning electron microscope, pyrolysis gas chromatography, dynamic light scattering, and atmospheric solid analysis probe (ASAP) paired with quadrupole mass spectrometry (MS). Short conclusion: The purpose of the present review is to give a summary of the most efficient cutting-edge techniques for more accurate and precise microplastic examination in the environmental samples. [ABSTRACT FROM AUTHOR]

Discrete linear polytopic systems affected by random correlated stationary disturbances are considered. New numerical methods for estimating of the anisotropic norm of a polytopic system using linear matrix inequalities are proposed. [ABSTRACT FROM AUTHOR]

The development of rapid chromatographic procedures is of utmost relevance to analytical laboratories since the modern pharmaceutical business is continually developing faster and more precise methods of drug discovery, development, distribution, and monitoring. Comprehensive two-dimensional (2D) chromatography is being developed as a tool to address challenges in the analysis of complex materials. Complex sample analyses may yield data that is challenging to quickly and accurately process. Here, chemometric analysis of data has shown to be the most fruitful and illuminating method. There are several applications for the determination of organic chemicals in samples with varying matrices. Gas/liquid chromatographic techniques are used for the bulk of organic chemical determinations. Therefore, it is crucial that these processes have minimal effects on the natural world. The collection and processing of samples, chromatographic separation, and final determination might all have less environmental impact if chromatographic methods were used. In both GC and LC, multidimensional separation methods may be used to improve the environmental friendliness of the analysis. The study describes 2D chromatographic techniques for GC-MS, 2D-LC, 2D-GC, 2D-CE, FTIR, and 2D-IR. Moreover, their advantages, challenges, and previous analytical data are also covered. [ABSTRACT FROM AUTHOR]

A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)–multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC–MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies. Particle sizes and number-based concentrations obtained by orthogonal batch methods (DLS, NTA, TRPS) were comparable for monodisperse spherical samples, while higher deviations were observed for polydisperse, agglomerated samples and for non-spherical particles, especially for light scattering methods. CLS and TRPS offer further insight with increased size resolution, while detailed morphological information can be derived by electron microscopy (EM)–based approaches. Combined techniques such as FFF coupled to MALS and RM can provide complementary information on physical and chemical properties by online measurements, while pyGC–MS analysis of FFF fractions can be used for the identification of polymer particles (vs. inorganic particles) and for their offline (semi)quantification. However, NPL analysis in complex samples will continue to present a serious challenge for the evaluated techniques without significant improvements in sample preparation. [ABSTRACT FROM AUTHOR]

Terpene synthases (TPSs) catalyze terpenoid synthesis and affect the intracellular isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) concentration. In this study, we mined the in silico genome-wide TPS genes of Hevea brasiliensis and identified 47 full-length TPS genes. They had DDXXD, DXDD, NSE/DTE, RR(X)8 W, EA(X)W, and other conserved motifs. The phylogenetic tree analysis revealed that the TPSs of H.brasiliensis (HbTPSs) were divided into five subfamilies, TPS-a, TPS-b, TPS-c, TPS-e/f, and TPS-g. HbTPSs were predicted to have functions in the cellular components, molecular functions, and biological processes. HbTPSs were involved in seven pathways, which were K14173, K14175, K15803, K04120, K04121, K17982, and K12742 in the secondary metabolite pathway prediction. Three-dimensional structures of HbTPSs of 7 pathways were predicted, and DDXXD, NSE/DTE, and EA(X)W conserved motifs near the binding sites were found. Cis-acting elements analysis showed that they had more cis-acting elements related to phytohormone responsiveness, which indicated that terpenoid biosynthesis might be related to phytohormone regulation. RNA-Seq analysis showed that different HbTPSs were expressed differentially in different tissues. This study's results help reveal the role of HbTPSs and their molecular mechanism and help resolve the regulatory mechanism of terpenoid biosynthesis in H.brasiliensis. [ABSTRACT FROM AUTHOR]

A rapid procedure for the determination of phenol and cresol isomers in drinking, sea, and polluted domestic wastewater is developed based on a single-stage extraction of analytes by extractive freezing-out under sample centrifugation conditions. In combination with gas chromatography, the procedure provides the minimum detection limits for each of phenols in 10 mL of water at a level of 0.0005 µg/mL. The duration of sample preparation does not exceed 30 min; the consumption of the ethoxyethane extractant is 1.4 mL. In comparison with liquid–liquid and solid-phase extraction traditionally used at the stage of sample preparation, the proposed procedure is simpler and more environmentally friendly. The stages of filtering samples and dehydrating extracts are excluded; the amount of chemical glassware is minimized. [ABSTRACT FROM AUTHOR]

The archaeological heritage at Cerrillo Blanco (Porcuna, Spain) is made up of 27 sculptural ensembles and hundreds of fragments dated between the seventh and second centuries BC. They represent a fundamental milestone in Iberian art and culture. Despite their relevance, no scientific studies have been carried out to date in order to fully understand the materials, intentions and techniques that led to their creation. This is a study carried out on original pieces from the Archaeological Museum of Jaén using stereoscopic optical microscopy (SOM), polarised optical microscopy (POM), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy with energy dispersive x-ray analysis (FESEM-EDX) and spectrophotometry (SF). The results obtained provide new information on the material composition of this important legacy of the Iberian civilization as well as its main alteration factors. [ABSTRACT FROM AUTHOR]

Metabolomics experiments generate highly complex datasets, which are time and work-intensive, sometimes even error-prone if inspected manually. Therefore, new methods for automated, fast, reproducible, and accurate data processing and dereplication are required. Here, we present UmetaFlow, a computational workflow for untargeted metabolomics that combines algorithms for data pre-processing, spectral matching, molecular formula and structural predictions, and an integration to the GNPS workflows Feature-Based Molecular Networking and Ion Identity Molecular Networking for downstream analysis. UmetaFlow is implemented as a Snakemake workflow, making it easy to use, scalable, and reproducible. For more interactive computing, visualization, as well as development, the workflow is also implemented in Jupyter notebooks using the Python programming language and a set of Python bindings to the OpenMS algorithms (pyOpenMS). Finally, UmetaFlow is also offered as a web-based Graphical User Interface for parameter optimization and processing of smaller-sized datasets. UmetaFlow was validated with in-house LC–MS/MS datasets of actinomycetes producing known secondary metabolites, as well as commercial standards, and it detected all expected features and accurately annotated 76% of the molecular formulas and 65% of the structures. As a more generic validation, the publicly available MTBLS733 and MTBLS736 datasets were used for benchmarking, and UmetaFlow detected more than 90% of all ground truth features and performed exceptionally well in quantification and discriminating marker selection. We anticipate that UmetaFlow will provide a useful platform for the interpretation of large metabolomics datasets. [ABSTRACT FROM AUTHOR]

This review is devoted to the consideration of prospects and directions for the development of methods and approaches to the analysis of high-purity industrial gases and volatile hydrides, chlorides, fluorides, and organoelement compounds with natural and isotopically enriched compositions. The currently known capabilities for the determination of impurities in them using mass spectrometry, IR spectroscopy, gas chromatography, and chromatography–mass spectrometry are analyzed. [ABSTRACT FROM AUTHOR]

Analytical characterization efforts carried out in support of the conservation treatment of Mark Rothko's painting 'Black on Maroon' 1958 (Tate T01170), involving the removal of graffiti (tag) ink, are summarized. The proprietary ink product, of unfamiliar and unknown composition, was investigated using a suite of analytical techniques (IR spectroscopy, GC–MS, ICP-MS, pyrolysis GC–MS, thin layer chromatography, SEC, MALDI-TOF–MS, and UHPLC-MS) to identify key colorants and other components. The ink solubility properties proved vital to informing the solvent selection process for the ink removal procedure, which helped enable the re-display of the painting at Tate Modern in 2014. The possible impact of ink residues remaining within the cotton duck canvas support of the conserved painting was also explored using mockup canvas mechanical strength data, measured before and after 'soiling' at two ink levels to assess whether the ink residues had any immediate and possible longer-term effects on canvas properties. These findings, elucidated using a range of complementary analytical techniques, provide information on this hitherto-unknown graffiti product, contribute to a growing body of knowledge in this area, and offer analytical approaches which may be useful for the characterization of similar unknown materials, whether used to damage, augment, or create works of art. [ABSTRACT FROM AUTHOR]

A numerical analytical approach to the study of the nonlinear deformation of shallow shells under subcritical loads is proposed. The approach rationally combines the generalized method of finite integral transforms and the Newton–Kantorovich–Raphson linearization method. The static stiffness and load–deflection relationship of flexible shallow shells with various boundary conditions in a wide range of changes in their Gaussian curvature and the presence of discrete inclusions are analyzed. It is shown that the dependence of the upper critical values of external pressure on the location of discrete inclusions is nonmonotonic, which makes it possible to determine their optimal location in terms of the static stability and bearing capacity of the shells. [ABSTRACT FROM AUTHOR]

Analysis of the results of experimental studies of bulk materials mixing process in a developed laboratory centrifuge having an adapter with alternating radial channels, nozzles and blades showed that the operating parameter of the device (rotation speed) has a significant effect on the pattern of distribution of the number of particles of each bulk component (in case of formation of rarefied component flows) along the height of the vertical trap. Particularly, with increase of the rotor speed by 1.67 times the maximum mass fraction of all particles of the descending rarefied flow shifts by one cell of the vertical trap. It was observed that for two types of mixtures (with 0.67 and 0.62 ratios of true densities of the substances of the key and transporting components) the conditions of their quality mixing are met. The obtained results may be useful for verification of stochastic models of formation of rarefied flows of particles of components being mixed using a rotating adapter with radial channels, nozzles and blades. [ABSTRACT FROM AUTHOR]

Purpose: The Pharmacy Service of the Infanta Leonor University Hospital acquires, compounds, distributes and dispenses more than 3000 L of methadone oral solution to Drug Addiction Patients Centers per year. Our purpose is to develop and validate an improved high performance liquid chromatography (HPLC) method to quantify methadone hydrochloride in a new oral solution with methylhydroxybenzoate (methylparaben) and propylhydroxybenzoate (propylparaben) to be implemented in physicochemical stability studies that allow to provide more information and even to increase the beyond-use date. Methods: A HPLC-Agilent® 1100 equipment, comprising a quaternary pump and an ultraviolet diode-array-detector (DAD) was used. An analytical method development and validation was completed. The curve was constructed from methadone working concentrations of 75–125% (7.5, 9.0, 10.0, 11.0 and 12.5 mg/mL) to assess the linear relationship between the concentration of the analyte and the obtained areas. Precision and accuracy were calculated. Detection and quantification limit (LD, LQ) were estimated using the EURACHEM method. Forced-degradation studies were also performed. Results: Chromatographic conditions were: flow rate 1.6 mL/min; mobile phase 55% acetonitrile and 45% sodium phosphate 25 mM (pH = 10); injection volume was 5 µL. The column was a Waters-XTerra™ RP18, maintained at 40 °C. DAD was λ = 254 nm. Retention times for methadone, methylparaben and propylparaben were 4.34, 0.70 and 0.88 min respectively. The method was linear (y = 284.3x − 97.8, r = 0.996). Instrumental precision was 0.33% for standards (n = 10); intra-assay precision 0.53% (n = 6) and inter-assay precision 1.95% (n = 12). The relative standard deviation percentage for accuracy was 1.28%. The recovery percentage was 101.5 ± 1.5%. LQ and LD were 2.18 µg/mL and 2.0 µg/mL respectively. The most destabilizing conditions were oxidizing and alkaline. The chromatograms confirmed no interference with the methadone signal. Conclusions: The HPLC method has proved to be valid and reproducible for methadone quantification in a new oral solution with methylparaben and propylparaben. This assay is a rapid, simple and reliable technique that can be used in daily analysis and physicochemical stability studies. [ABSTRACT FROM AUTHOR]

A reproducible, sensitive, and cost-effective spectrofluorimetric method has been developed for quantification of the drug ibrutinib in bulk and in its oral capsule formulation. The method was validated in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use guidelines with respect to linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), and robustness. The method was found to be extremely sensitive, and excellent linearity was noted within the concentration range 0.1–7.5 μg/mL with a correlation coefficient (r2) of 0.9961. The LOD and LOQ values for the proposed method were found to be 0.224 and 0.680 μg/mL, respectively. Excellent recoveries of the drug were observed from the marketed capsule formulation by the proposed method (97.59, 1.42% relative standard deviation). [ABSTRACT FROM AUTHOR]

The reconfigurable manufacturing system is an advanced field of research that has surpassed the efficiency of other manufacturing systems due to its high throughput, cost-effectiveness, and ability to accommodate product variety. An important problem addressed in the field of reconfigurable manufacturing systems is process planning which assigns configurations to different operations. Process planning has been the focus of research for almost two decades; however, a comprehensive review is lacking to highlight the possible streams of future contributions to this field of research. To this end, this study presents a systematic review of the process planning in a reconfigurable manufacturing system with a focus on optimization efforts. This review is organized in two interconnected phases, i.e., a theoretical phase and an implementation phase. The theoretical phase reviews the concerned literature regarding the levels of analysis, reconfigurable manufacturing system (RMS) characteristics, different research themes, and change agents. On the other hand, the implementation phase reviews the literature regarding the use of different objective functions, constraints, solution approaches, nature of problem/solution, and the use of industrial applications. Several future research streams are provided which can guide, in a broader sense, the advancement of process planning literature. As a demonstration, quality, supply chain, and human/operator issues are highlighted to advance the scope of applicability of the concerned literature. A thorough analysis of the operator aspects in scheduling literature is presented which can benefit practitioners working in a changeable/reconfigurable manufacturing environment. Moreover, practical process planning approaches are offered to analyze the cost, time, and quality aspects. Finally, the conclusion of the study is provided. [ABSTRACT FROM AUTHOR]

Luminescent quantum dots (QDs) of I–III–VI2 semiconductors present a new class of luminescence materials that combine unique optical and electronic properties while exhibiting low toxicity compared to conventional cadmium-based QDs. Advances in the colloidal synthesis of ternary QDs have been used to develop fluorescence chemical and biological sensors for the detection of various analytes. The review covers the main approaches to synthesizing QDs of the I–III–VI2 structure, the features of their structure and properties, and current trends in their use as low-toxic luminescent labels in biomedicine and chemical analysis. [ABSTRACT FROM AUTHOR]

Background: The purpose of this article is to evaluate the positivity of conjunctival sac swab by PCR (Polymerase chain reaction) test in COronaVIrus Disease 19 (COVID-19) patients. Methods: Inclusion criteria of our study were COVID-19 patients hospitalized during March 2021 in inpatient wards at University Hospitals in towns Bratislava and Zilina, Slovakia. The conjunctival sac swabs collected by four ophthalmologists were stored for 24 h, then analyzed in the laboratory of the Department of Microbiology and Immunology, Jessenius Faculty of Medicine in Martin, Comenius University, Slovakia. The sampling apparatus, used for conjunctival sac swab, was the Dacron polyester swab. Results: We examined one group of 302 COVID-19 patients, 168 Male (56%) and 134 Female (44%). The patients' mean age was 66.3 ± 13.66 years, ranging from 25 to 96 years, and the mean length of hospital stay in our patients with a nasopharyngeal positive PCR test was 7.33 ± 4.76, from 2 to 24 days. The PCR tests from the conjunctival sac swabs were positive in 33 patients (11%), negative in 259 patients (86%), and ten patients (3%) were with the unclear result. In the group of 33 positive patients were 17 males with a mean age of 74.6 ± 13.59 years and 16 females with a mean age of 70.63 ± 14.17 years. The cycle threshold (CT) values differed significantly between conjunctival sac swabs from the nasopharynx and the conjunctiva. Medians of the values were 25.1 (14.1, 32.1) and 31.5 (22.6, 36.6) (P < 0.001), respectively. Conclusion: This study affirmed that in COVID-19 patients the SARS-CoV-2 was detectable with PCR test in conjunctival sac swab, but the positivity rate was only about one to ten cases (11%). [ABSTRACT FROM AUTHOR]

Recently, big data are widely noticed in many fields like machine learning, pattern recognition, medical, financial, and transportation fields. Data analysis is crucial to converting data into more specific information fed to the decision-making systems. With the diverse and complex types of datasets, knowledge discovery becomes more difficult. One solution is to use feature subset selection preprocessing that reduces this complexity, so the computation and analysis become convenient. Preprocessing produces a reliable and suitable source for any data-mining algorithm. The effective features' selection can improve a model's performance and help us understand the characteristics and underlying structure of complex data. This study introduces a novel hybrid feature selection cloud-based model for imbalanced data based on the k nearest neighbor algorithm. The proposed model showed good performance compared with the simple weighted nearest neighbor. The proposed model combines the firefly distance metric and the Euclidean distance used in the k nearest neighbor. The experimental results showed good insights in both time usage and feature weights compared with the weighted nearest neighbor. It also showed improvement in the classification accuracy by 12% compared with the weighted nearest neighbor algorithm. And using the cloud-distributed model reduced the processing time up to 30%, which is deliberated to be substantial compared with the recent state-of-the-art methods. [ABSTRACT FROM AUTHOR]

We substantiate an approach to the creation of a device for establishing gross adulteration of gasoline by replacing their part with fuel with a lower octane number and demonstrate the application of mass-sensitive sensor electrodes using the specific features of the adsorption of volatile compounds from the headspace of gasoline with different octane numbers (AI-92, AI-95) by the sensor modifiers. The results helped select three coatings most sensitive and selective to traces, differently adsorbing compounds of the highly volatile gasoline fraction. Simple recorded and calculated signals of the "electronic nose" SΣ, Sτ, A(i/j), AS(τ1/τ2), giving information on the composition of a gasoline sample and assessing the change in composition on adding fuel of a different type or brand, are proposed. The algorithm for calculating and making a decision is simple and can be programmed into the microcircuit of a mobile device. Introducing an "electronic nose" gas analyzer based on piezoelectric balances into the fuel quality control system is helpful to reveal the facts of adulteration of high-octane gasoline by adding gasoline with a lower octane number and to estimate the amount of the additive. A method is developed for in situ analysis performed by experts or untrained users; it readily gives an assessment of adulteration with an additive concentration of 6 to 50 vol % with an error of no more than 12%. [ABSTRACT FROM AUTHOR]

A rapid, sensitive, cost effective and reproducible first-order derivative spectrophotometric method was developed for the estimation of gefitinib in bulk and in its marketed formulation. Preliminary spectrophotometric determination of the drug was carried out in acetate buffer pH 2.8 and in 0.1 N HCl with a total of 20 parametric variations. The selected method with three parametric variations employing peak–zero (P–0) and peak–peak (P–P) techniques was assessed for stability indicating potential in force degraded solutions. The developed method was validated with respect to linearity, accuracy, precision, and robustness. Linearity was observed in the concentration range of 5–50 μg/mL with an excellent correlation coefficient (r2) of 0.999. The limits of assay detection values were found for the range from 1.69–3.75 μg/mL, and quantitation limits ranged from 5.11–12.71 μg/mL for the proposed method. The proposed method was applicable for the determination of the drug in its marketed tablet formulation, and percentage recovery was found for the range from 97.42 to 98.58%. [ABSTRACT FROM AUTHOR]

Roller clinching is a variation of conventional clinching by using rotational tool movement. The joining quality of roller clinching is significantly affected by tooling geometries and motions. Considering the formation difference of joints at different locations, this paper investigated the deformation features of roller clinching of square joints and utilized multiple linear regression analysis to optimize the processing parameters. It was found that roller geometry has significant impact on the formation of interlocks of the front/rear sides of joints, while the impact on the formation of lateral sides is less. With the increase of roller diameters, the clearance variation of front/rear sides decreases; meanwhile, the separation clearance s at the front side after forming decreases. In the study, when the roller diameter is raised from 35 to 150 mm, the connection strength increases by 44%. If the diameter difference w of rollers increases, the squeezing degree of the front side decreases, and the joining quality increases; however, if the squeezing degree of the rear side increases, then the joining quality of the rear side and s decrease. In the sample, an increase in w by 3 mm enhanced the connection strength by 9%. When the clearance difference t between the rollers increases, the capability to contain metal increases in the rear side. When t increases by 0.6 mm, the connection strength augments by 12%. The separation clearance s of the front side is greatly affected by friction μ, roller diameter, w, and draft angle γ of the lower roller, while the effect of draft angle β of the upper roller on s is small. [ABSTRACT FROM AUTHOR]

The results of analytical calculations of T-joints in process pipelines in conformity with GOST 32388-2013, GOST 34233.3-2017, and ASME B31.3-2002 regulatory documents are compared. A numerical study of stresses at T-joints was conducted using finite-elements method. Data were obtained on the influence of dimensions of cover rings on reinforcement of T-joint in pipelines. The results of numerical and analytical calculations of T-joints are compared. [ABSTRACT FROM AUTHOR]

A reproducible, sensitive, and cost-effective spectrofluorimetric method has been developed for the quantification of azelastine hydrochloride in its bulk and nasal formulations. The stability-indicating potential of the method was assessed by recovery studies in the forced degraded solutions of the drug. The method was validated in accordance with the ICH guidelines with respect to linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), and robustness. Excellent linearity was noted in the concentration range 2.0–40.0 μg/mL with a correlation coefficient (R2) of 0.9961. The limits of detection and quantitation for the proposed method were found to be 0.1598 μg/mL and 0.4845 μg/mL respectively. Excellent recovery of the drug was obtained from the proposed method in the nasal spray formulation of the drug (96.5, 0.66% RSD). The stability-indicating potential of the method was assessed from recovery studies of the drug from various forced-degraded samples spiked with known drug concentrations. The studies indicated a high rate of degradation in alkaline, oxidative, and photolytic stress degraded solutions. [ABSTRACT FROM AUTHOR]

We demonstrated a possibility of using a chemical sensor array for the control of the formation of the aroma of confectionery masses during conching. The correlation between the results of sensor-metric analysis and physical and chemical indicators of the quality of confectionery masses was evaluated. An array of chemical sensors enables the assessment of the intensity and shift of the composition of the aroma during conching as the key stage of production. It ensures a rapid assessment of standard indicators, that is, the acid number of lauric substitute for cocoa butter by the signal of the sensor with polyethylene glycol adipate (Pearson's correlation degree R = 0.94), the acidity of confectionery masses of different nature by the signals of sensors based on crown ether and Tween-40 (R = 0.90–0.92). The most valuable achievement is the ability of controlling the decrease in the concentration of nonvolatile compounds and the total concentration of sugars and reducing sugars during conching, based on the signals from two sensors (R = 0.90–0.93). We also show a possibility of introducing an electronic nose gas analyzer based on adsorption-type sensors into the control system of confectionery production for determining physical and chemical parameters and digitizing the most unstable property, that is, aroma, compliance and optimization of recipes, an objective and reproducible assessment of the quality of raw materials and confectionery products, and the control of the reproducibility of the integral indicator (aroma) for different batches of finished products. [ABSTRACT FROM AUTHOR]

Low-carbon steel St37-2 is widely used in the bus-production industry. The gas-metal arc welding (GMAW) is strongly applied to join steel components due to its ease and low cost. Heat-affected zone (HAZ) is the area between the weld and the base metal, where the welded joint may have the lowest toughness and, hence, it has always been a matter of interest for numerous researchers. Our aim is to study the effects of GMAW parameters on the width of the HAZ. The Taguchi orthogonal array, signal-to-noise (S/N) ratios, and the analysis of variance (ANOVA) are used to investigate and analyze the effect of the welding parameters on the HAZ width. [ABSTRACT FROM AUTHOR]

Luminescence semiconductor quantum dots (QDs) offer a rather new type of luminescent labels used for the visual and instrumental determination of analytes in various versions of chemical analysis. The high quantum yield, photostability, narrow emission spectra, and wide excitation regions of these species make them ideal labels for analysis and ensure the development of procedures for the simultaneous determination of several substances and the attainment of low limits of detection. The widespread introduction of QDs in analytical practice is limited by the multistage character and laboriousness of some approaches to the synthesis of QDs and reagents on their basis, their trend to nonspecific interactions, and a probability of fluorescence reabsorption at the improper selection of the concentration of QDs. The review covers the main approaches to the synthesis, modification, and use of luminescence QDs in chemical analysis. Approaches to the sensitization and multiplicity of analysis and methods for regulating selectivity based on both the properties of QDs and, in addition, the receptors used are discussed. [ABSTRACT FROM AUTHOR]

The fractional Hopfield neural network (HNN) model is studied here analyzing its symmetry, uniqueness of the solution, dissipativity, fixed points etc. A Lyapunov and bifurcation analysis of the system is done for specific as well as variable fractional order. Since a very long time ago, HNN has been carefully studied and applied in various fields. Because of the exceptional non-linearity of the neuron activation function, the HNN system is stoutly non-linear. Chaos control using adaptive SMC considering disturbances and uncertainties is done about randomly chosen points by designing suitable controllers. Numerical simulations performed in MATLAB verify the efficacy of the designed controllers. [ABSTRACT FROM AUTHOR]

ChemSpectra, a web-based software to visualize and analyze spectroscopic data, integrating solutions for infrared spectroscopy (IR), mass spectrometry (MS), and one-dimensional 1H and 13C NMR (proton and carbon nuclear magnetic resonance) spectroscopy, is described. ChemSpectra serves as web-based tool for the analysis of the most often used types of one-dimensional spectroscopic data in synthetic (organic) chemistry research. It was developed to support in particular processes for the use of open file formats which enable the work according to the FAIR data principles. The software can deal with the open file formats JCAMP-DX (IR, MS, NMR) and mzML (MS) proposing these data file types to gain interoperable data. ChemSpectra can be extended to read also other formats as exemplified by selected proprietary mass spectrometry data files of type RAW and NMR spectra files of type FID. The JavaScript-based editor can be integrated with other software, as demonstrated by integration into the Chemotion electronic lab notebook (ELN) and Chemotion repository, demonstrating the implementation into a digital work environment that offers additional functionality and sustainable research data management options. ChemSpectra supports different functions for working with spectroscopic data such as zoom functions, peak picking and automatic peak detection according to a default or manually defined threshold. NMR specific functions include the definition of a reference signal, the integration of signals, coupling constant calculation and multiplicity assignment. Embedded into a web application such as an ELN or a repository, the editor can also be used to generate an association of spectra to a sample and a file management. The file management supports the storage of the original spectra along with the last edited version and an automatically generated image of the spectra in png format. To maximize the benefit of the spectra editor for e.g. ELN users, an automated procedure for the transfer of the detected or manually chosen signals to the ELN was implemented. ChemSpectra is released under the AGPL license to encourage its re-use and further developments by the community. [ABSTRACT FROM AUTHOR]

Fourier transform infrared (FTIR) microspectroscopy provides a biochemical fingerprint of the cells. In this study, chemical changes in 143B osteosarcoma cells were investigated using FTIR analysis of cancer cells after their treatment with polymeric invertible micellar assemblies (IMAs) and curcumin-loaded IMAs and compared with untreated osteosarcoma cells. A comprehensive principal component analysis (PCA) was applied to analyze the FTIR results and confirm noticeable changes in cell surface chemical structures in the fingerprint regions of 1480–900 cm−1. The performed clustering shows visible differences for all investigated groups of cancer cells. It is demonstrated that a combination of FTIR microspectroscopy with PCA can be an efficient approach in determining interactions of osteosarcoma cells and drug-loaded polymer micellar assemblies. [ABSTRACT FROM AUTHOR]

It has been 36 years since ISO 4298:1984 was published, yet the role of sodium pyrophosphate in the oxidation of manganese(II) by potassium permanganate in this standard has not been fully recognized. The sample and reagent dosages exceed the actual detection needs, which creates challenges in the test operation and waste liquid treatment. In this study, a more scientific expression for the principle and reaction and the dosage of pyrophosphate in ISO 4298:1984 are discussed. The pyrophosphate ligand is involved in the oxidation of manganese(II) by potassium permanganate, and plays a role in preventing Mn(II) precipitation or Mn(III) dismutation during the whole reaction. The most appropriate amount of saturated sodium pyrophosphate is 150 mL for the test of manganese ores and concentrates with manganese content from 15% to 60%. The method developed by reducing sample size and reagent consumption was evaluated with ten certified reference materials, showing high accuracy and meeting the analytical performance requirements. These results can provide technical support for the revision of ISO 4298:1984. [ABSTRACT FROM AUTHOR]

The article presents the classification of the gas stream contaminant types in noble gas enrichment and purification units. For the safe and efficient system operation, it is necessary to choose the right method of multicomponent mixture separation and the optimal corresponding equipment operating parameters, also to offer a method to verify the absence of the undesirable contaminant in the gas stream. The methods to control the obtaining of required noble gas purity during cryogenic rectification are indicated. Application of various gas analysis methods is necessary to obtain high purity (up to 99.9999%) gases: gas chromatography, mass spectrometry, and their combination. The effect of the state of various components of a gas chromatograph on the analysis result are discussed. Recommendations are provided for noble gas analysis methodology, including the conditions for the determination of trace impurities. The article presents examples of practical application of gas chromatography to control the processes of noble gas enrichment and purification, using the example of production of pure xenon. [ABSTRACT FROM AUTHOR]

Background: The water volume of the endothelial glycocalyx layer has been estimated at 0.7 to 1.7 L using tracer methods of unclear value. The present study attempts to measure this fluid volume by analyzing the kinetics of a crystalloid fluid load. Methods: An intravenous infusion of approximately 1 L of Ringer's acetate was administered to 35 healthy volunteers, and the central volume of distribution of the water volume was calculated from the urinary excretion and frequent measurements of the fluid-induced hemodilution using mixed-effects modeling software. Comparisons were made with the plasma volume derived from three published anthropometric regression equations based on isotope measurements. In a second analysis, up to 2.5 L of Ringer's was administered to 60 volunteers selected from a cohort of 160 to have as similar hematocrits as possible to the volunteers whose data were used to create the anthropometric equations. Results: Volume kinetics showed that the infused crystalloid fluid occupied a larger central fluid space than was estimated with the isotope measurements. The first analysis of the 35 subjects indicated a mean difference of 0.51 L in males and 0.49 L in females. The second, larger analysis showed a mean excess volume of 0.43 L, which was approximately 15% of the circulating plasma volume. Conclusions: A crystalloid fluid load expands a 0.4–0.5 L larger central fluid space than the circulating plasma volume. The excess volume is probably located in the glycocalyx layer. [ABSTRACT FROM AUTHOR]

As an important engineering material, aluminum alloy profile is widely used in each department of national economy. With polyurethane mandrel in the hollow of the profiles, equal channel angular pressing (ECAP) can be used to refine mechanical properties of these hollow materials with good shape control effects. However, based on existing researches, the hollow profiles are only limited to circular ones. In this paper, a mechanical analysis of a square tube in ECAP with polyurethane mandrel is provided. Through the slab method in different deformation planes, the mechanical mechanism of shape control effects is found. The thicknesses can be maintained as its initial ones after ECAP. Both simulations and experiments are used to verify the calculated results by the analysis. After calculating, most errors between the final and initial thicknesses in both simulations and experiments are less than 10%. [ABSTRACT FROM AUTHOR]

The occurrence of polar pesticides in sediments has not been extensively investigated because of their relatively poor hydrophobicity and apparently less persistence in the environment. However, their continuous release into the aquatic systems calls for the evaluation of their potential accumulation in sediments and the role of this matrix as a potential source of these compounds. Considering this, a method based on pressurized liquid extraction (PLE), extract clean-up by solid phase extraction (SPE), and analyte determination by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed and validated to analyze 50 relevant (frequently used and/or regulated or found in water) medium to highly polar pesticides in sediments. The method showed good performance regarding accuracy (relative recoveries between 76 and 124%), precision (relative standard deviation values < 20%), sensitivity (LODs in the low nanogram per gram for most compounds), linearity (coefficients of determination > 0.99), and matrix effects (negligible for all analytes). The use of an isotope dilution approach for quantification ensures result reliability. As a part of the validation process, the method was applied to the analysis of the target pesticides in sediments from the Llobregat River (NE Spain) showing the presence of five of them, namely, terbutryn, dichlorvos, terbuthylazine, diazinon, and irgarol. All 5 pesticides, due to both the concentrations found and their physical-chemical characteristics, demonstrate high potential for bioaccumulation and risk to aquatic organisms. Additional multi-disciplinary studies that investigate pesticide occurrence in different aquatic compartments and evaluate the potential risks for aquatic ecosystems are required to assess the environmental impact and significance of the presence of pesticides in sediments. [ABSTRACT FROM AUTHOR]

This paper presents a new multi-residue method for the quantification of more than 142 anthropogenic compounds of emerging concern (CECs) in various environmental matrices. These CECs are from a wide range of major classes including pharmaceuticals, household, industrial and agricultural. This method utilises ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) for analysis of five matrices (three liquid and two solid) from wastewater treatment processes and the surrounding environment. Relative recoveries were predominantly between 80 and 120%; however, due to the complexity of the matrices used in this work, not all compounds were recovered in all matrices, from 138/142 analytes in surface water to 96/142 analytes in digested solids. Method quantification limits (MQLs) ranged from 0.004 ng L−1 (bisoprolol in surface water) to 3118 ng L−1 (creatinine in wastewater treatment work (WwTW) influent). The overall method accuracy was 107.0%, and precision was 13.4%. To test its performance, the method was applied to the range of environmental matrices at WwTWs in South West England. Overall, this method was found to be suitable for application in catchment-based exposure-driven studies, as, of the total number of analytes quantifiable in each matrix, 61% on average was found to be above their corresponding MQL. The results confirm the need for analysing both the liquid and solid compartments within a WwTW to prevent under-reporting of concentrations. [ABSTRACT FROM AUTHOR]

Self-propelled micromotors are micro- and nanoscale devices that move autonomously in solution by converting a specific stimulus into mechanical work. The broad scope of operations and applications along with the ultra-small dimensions have opened new possibilities to solve complex analytical challenges. Herein we give a critical overview of early developments and future prospects of such tiny moving objects for different analytical sensing and biosensing strategies. From early electrophoretic propelled nanomotors, which were limited to low viscous media, to bubble-propelled micromotors, the field has evolved into sophisticated all-in-one analytical systems with built-in sensing capabilities. Current progress for in vivo biosensing and integration into analytical instrumentation towards fully functional devices will be also covered. We hope that this review provides the reader with some general knowledge and future prospects of self-propelled micromachines as a new paradigm in analytical chemistry. [ABSTRACT FROM AUTHOR]

We considered the physicochemical regularities and analytical capabilities of separation methods based on the manifestation of capillary effects in hydrophobic microporous media, namely, liquid–gas chromatography with a stationary gas phase in the pores of a solid-phase substrate and a mass-exchange process in liquid–gas and liquid–liquid systems, carried out in a biporous matrix. The advantages of these methods compared to conventional mass-exchange processes in the same systems in terms of higher efficiency and a possibility of the separation of substances in a continuous mode are shown. [ABSTRACT FROM AUTHOR]

Secondary organic aerosol (SOA) accounts for a significant fraction of particulate matter (PM) in the atmosphere. Source identification, including the SOA fraction, is critical for the effective management of air pollution. Molecular SOA markers (tracers) are key compounds allowing the source apportionment of SOA using different methodologies. Therefore, accurate SOA marker measurements in ambient air PM are important. This study determined the concentrations of 12 key SOA markers (biogenic and anthropogenic) in the urban dust standard reference material available from the National Institute of Standards and Technology (NIST) (SRM 1649b). Two extraction procedures, sonication and QuEChERS-like (quick easy cheap effective rugged and safe), have been compared. Three research laboratories/institutes using two analytical techniques (gas chromatography/mass spectrometry (GC/MS) and ultra-high-pressure liquid chromatography/tandem mass spectrometry (HPLC/MS-MS)) carried out the analyses. The results obtained were all in good agreement, except for 2-methylerythritol. The analysis of this compound still seems to be challenging by both GC/MS (large injection repeatability) and HPLC/MS-MS (separation issues of both 2-methyltetrols: 2-methylthreitol and 2-methylerythritol). Possible inhomogeneity in the SRM for this compound could also explain the large discrepancies observed. Sonication and QuEChERS-like procedures gave comparable results for the extraction of the SOA markers showing that QuEChERS-like extraction is suitable for the analysis of SOA markers in ambient air PM. As this study provides, for the first time, indicative values in a reference material for typical SOA markers, the analysis of SRM 1649b (urban dust) could be used for quality control/assurance purposes. [ABSTRACT FROM AUTHOR]

Antibiotics may be present in agricultural soils through the application of organic amendments as fertilizers or by irrigation of fields with recycled water. As a result of these agricultural practices, antibiotics in soil can lead to their uptake by plants, entering in this way the food chain. Studies on the levels of antibiotics in cereal samples are scarce in the available literature. In this work, an analytical method was developed for the determination of 19 antibiotics (fluoroquinolones, sulfonamides, tetracyclines, and lincosamides) in four types of cereal grains (wheat, barley, rice, and oat). Ultrasound-assisted matrix solid-phase dispersion was selected as extraction technique with recoveries of target analytes ranging from 73 to 127% for the four cereals analyzed. Limits of quantification obtained ranged from 0.8 to 5.8 ng g−1. Compared with methods described for the analysis of antibiotics in cereals, the developed method uses a lower volume of extraction solvent and very good recoveries were obtained for all compounds. The validated method was applied to the analysis of different types of cereals samples, harvested from agricultural fields or purchased from local supermarkets. The analysis of the five cereal samples grown in fields with 3 years of consecutive organic amendments revealed that none of the nineteen antibiotics selected were found in any sample. Eleven commercial samples of cereals of different types and presentations were analyzed and enrofloxacin was detected in one rice sample; the presence of enrofloxacin in cereals or its incorporation into crops from soil or water not previously reported. [ABSTRACT FROM AUTHOR]

Fractional circuits have attracted an extensive attention of scholars and researchers for their superior performance and potential applications. The passive realization of the fractional-order immittance function plays an important role in fractional circuits theory, which is useful in fractional circuits design and modeling. This paper deals with the analysis and passive synthesis of fractional two-element-kind network. Firstly, the time-domain response of fractional two-element-kind network is analyzed based on its immittance function expressions, and the response shows oscillation only in fractional L β C α circuits. Then, necessary and sufficient conditions to realize the fractional-order immittance functions by a passive network with only two kinds of elements are obtained in view of impedance scaling. A procedure is also proposed to realize such immittance functions using two-element-kind network. Finally, three examples are given to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

Flexible manufacturing system (FMS) is one of the solutions that enables any manufacturing system to withstand changing requirements of the market. An FMS consists of different automated workstations, material handling devices, and storage systems, all of which work under computer control. In the present work, analysis and modeling of a real problem has been considered for performance improvement. Modeling is done for analyzing the performance of an existing model, to propose a new layout for the system. Effect of factors like part mix, layout type, and batching condition, on the system performance in terms of productivity, system utilization rate, and cycle time is analyzed. The work includes simulation study along with Taguchi's experimental design framework for studying how different factors with varying levels affect system performance. ProModel software is used for simulating existing and proposed models of the manufacturing firm. Further, analysis of variance (ANOVA) is employed for finding the most important factor that affects system performance. Proposed methodology helps in determining best factor-level combination for each performance parameter. The results show that the system performs well with the implementation of loop layout having many numbers of batches. Towards the end, the scope of further is highlighted. [ABSTRACT FROM AUTHOR]

The basic regularities of an acid retardation method for the chromatographic separation of mixtures in concentrated acidic solutions and its new versions, which are convenient for use in technology and chemical analysis, developed by the authors are described. The results of studies on the application of a new approach to the separation of electrolyte mixtures with the use of columns in which an anion exchanger bed was filled with an organic liquid immiscible with water and aqueous solutions are presented. With the use of the separation of the components of model mixtures containing nitric acid and its salts, the natural solutions of the acid decomposition of bone tissue, and soil on the AV-17 anion exchanger in nitrate form as examples, it is demonstrated that the approach proposed is promising for sample preparation in chemical analysis, in particular, for effectively reducing the acidity of solutions after the digestion of difficult-to-decompose samples. The reproducibility of the results obtained using this approach was evaluated by analyzing the elution curves of the sorption–desorption of the macrocomponents of bone mineralization solution in repeated experiments. [ABSTRACT FROM AUTHOR]

The review summarizes authors' works of the last 15 year covering the possibilities, advantages, and prospects for the use of optical sensors based on peroxidase for the determination of a wide range of biologically active compounds, i.e., phenolic compounds and hydroperoxides of different structures, phenothiazines, catecholamines, and their metabolites, for the quality control of drugs, foodstuffs, biomedical research, and clinical diagnostics. [ABSTRACT FROM AUTHOR]

Glass of the хAg2O ⋅ (1 – х)B2O3 silver borate system (x = 0.5–47 mol %) is obtained under different conditions. According to the chemical analysis, the composition of the glass changes during the synthesis relative to the calculated one. It is shown that when the synthesis temperature is 850°C and the time is 90 min the relative decrease in the Ag2O content is 3–5% at an Ag2O concentration in the range of 5 to 30%. In this regime of synthesis, the losses are minimal where the Ag2O content ranges from 20 to 30 mol %. When the synthesis temperature is 1050°C and the time of synthesis is 60 min, the relative losses sharply increase with the growth of the Ag2O content from 30 to 47%. Increasing the synthesis temperature results in a significant growth of the relative losses. The glass forming region of the silver-borate system is expanded. [ABSTRACT FROM AUTHOR]

This paper focuses on the automatic recognition of map projection, its inverse and re-projection. Our analysis leads to the unconstrained optimization solved by the hybrid BFGS nonlinear least squares technique. The objective function is represented by the squared sum of the residuals. For the map re-projection the partial differential equations of the inverse transformation are derived. They can be applied to any map projection. Illustrative examples of the stereographic and globular Nicolosi projections frequently used in early maps are involved and their inverse formulas are presented. [ABSTRACT FROM AUTHOR]

The substance group of very volatile organic compounds (VVOCs) is moving into the focus of indoor air analysis, facing ongoing regulations at international and European levels targeting on indoor air quality and human health. However, there exists at present no validated analysis for the identification and quantification of VVOCs in indoor air. Therefore, the present study targeted on the development of an analytical method in order to sample the maximum possible quantity of VVOCs in indoor air on solid sorbents with subsequent analysis by thermal desorption and coupled gas chromatography/mass spectrometry (TDS-GC/MS). For this purpose, it was necessary to investigate the performance of available sorbents and to optimize the parameters of GC/MS analysis. Stainless steel tubes filled with Carbograph 5TD were applied successfully for low-volume sampling (2-4 l) with minimal breakthrough (< 1%). With the developed method, VVOCs between C3 and C6 of different volatility and polarity  can be detected even in trace quantities with low limits of quantitation (LOQ; 1-3 μg m−3). Limitations occur for low molecular weight compounds ≤C3, especially for polar substances, such as carboxylic acids and for some aldehydes and alcohols. Consequently, established methods for the quantification of these compounds in indoor air cannot be fully substituted yet. At least three different analytical techniques are needed to cover the large spectrum of relevant VVOCs in indoor air. In addition, unexpected reaction products might occur and need to be taken into account to avoid misinterpretation of chromatographic signals.Solid sorbent sampling of VVOCs (C3-C6) in indoor air with subsequent TDS-GC/MS analysis [ABSTRACT FROM AUTHOR]

Background: Rapid prototyping (RP) is used widely in dental and faciomaxillary surgery with anecdotal uses in orthopedics. The purview of RP in orthopedics is vast. However, there is no error analysis reported in the literature on bone models generated using office-based RP. This study evaluates the accuracy of fused deposition modeling (FDM) using standard tessellation language (STL) files and errors generated during the fabrication of bone models. Materials and Methods: Nine dry bones were selected and were computed tomography (CT) scanned. STL files were procured from the CT scans and three-dimensional (3D) models of the bones were printed using our in-house FDM based 3D printer using Acrylonitrile Butadiene Styrene (ABS) filament. Measurements were made on the bone and 3D models according to data collection procedures for forensic skeletal material. Statistical analysis was performed to establish interobserver co-relation for measurements on dry bones and the 3D bone models. Statistical analysis was performed using SPSS version 13.0 software to analyze the collected data. Results: The inter-observer reliability was established using intra-class coefficient for both the dry bones and the 3D models. The mean of absolute difference is 0.4 that is very minimal. The 3D models are comparable to the dry bones. Conclusions: STL file dependent FDM using ABS material produces near-anatomical 3D models. The high 3D accuracy hold a promise in the clinical scenario for preoperative planning, mock surgery, and choice of implants and prostheses, especially in complicated acetabular trauma and complex hip surgeries. [ABSTRACT FROM AUTHOR]

A pneumovacuum circuit of a Tsvet-800-2 gas chromatograph with a helium ionization detector (HID) in the ionization amplification mode is proposed for controlling limiting trace impurities in ammonia, arsine, monosilane, and phosphine of grade 6N4. The conditions for the preparation and reliable operation of the chromatograph with the HID are systematized. The effect of an additive of (0.0-17.6) × 10 mol % of hydrogen in the carrier gas of the detector on the polarity of its signal on the impurities of oxygen and nitrogen at a level of (0.5-20.0) × 10 mol % is studied. Methods are proposed for eliminating systematic errors in the determination of the concentration of oxygen and nitrogen in the range from 0.5 × 10 to 1 × 10 mol % in 6N4 volatile hydrides, caused by 'counter' impurities in the carrier gas, the mechanism of the heteropolar sensitivity of the HID, and irreversible chemical reactions of oxygen traces with phosphine and products of its decomposition on a CaA-ShM zeolite in a separating column of a chromatograph. Gas chromatography analysis of ammonia, arsine, monosilane, and phosphine of grade 6N4 was carried out. [ABSTRACT FROM AUTHOR]