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1. An introduction to hand-held infra-red and Raman instrumentation

Author:
Analytical Methods Committee, AMCTB No. 94,
Source:
Analytical methods 2020 v.12 no.11 pp. 1532-1535
ISSN:
1759-9679
Subject:
chemical analysis,   etc   ; environmental protection; equipment; instrumentation; manufacturing;     Show all 5 Subjects
Abstract:
... The past 20 years have seen widening applications of hand-held instruments which facilitate operation outside the confines of a laboratory thereby enabling on-site and in situ analysis of test materials with limited or no test material preparation. Hand-held infra-red and Raman instrumentation is now available for a wide range of applications in fields such as manufacturing, environmental protecti ...
DOI:
10.1039/d0ay90025g

2. Design of smart chemical ‘tongue’ sensor arrays for pattern-recognition-based biochemical sensing applications

Author:
Chen, Zi-Han; Fan, Qian-Xi; Han, Xin-Yue; Shi, Guoyue; Zhang, Min
Source:
Trends in analytical chemistry 2020 v.124 pp. 115794
ISSN:
0165-9936
Subject:
chemical analysis,   etc   ; biochemical pathways; sensors (equipment);     Show all 3 Subjects
Abstract:
... Conventional molecular recognition was tightly related to the development of analyte-specific sensor. However, all most every biochemical process are not decided on only one factor. When several factors were imported simultaneously, the established sensor could be seriously interfered and gave the wrong response. In this regard, chemical tongue-mimic sensor array was promoted to recognize a set of ...
DOI:
10.1016/j.trac.2019.115794

3. Robustness assessment in computer-assisted liquid chromatography procedures based on desirability functions

Author:
Triñanes, S.; Rodriguez-Mier, P.; Cobas, C.; Sánchez, E.; Phan-Tan-Luu, R.; Cela, R.
Source:
Journal of chromatography 2020 v.1609 pp. 460439
ISSN:
0021-9673
Subject:
chemical analysis,   etc   ; computer analysis; liquid chromatography; models;     Show all 4 Subjects
Abstract:
... A novel approach based on the use of desirability functions is presented for the robustness assessment of liquid chromatographic separations as derived from computer-assisted methods development processes. The approach is based on generally accepted hypothesis that a robust separation procedure will be inert to small random variations of the operational variables, typically encountered in the day- ...
DOI:
10.1016/j.chroma.2019.460439

4. Structure of a heptose-containing polysaccharide derived from Komagataeibacter europaeus NBRC 3261

Author:
Devanthéry, Thierry; Nakamura, Keisuke; Hashiguchi, Shuhei; Hashimoto, Masahito
Source:
Carbohydrate research 2020 v.492 pp. 107989
ISSN:
0008-6215
Subject:
chemical analysis,   etc   ; O-antigens; carbohydrate structure; galactose; stable isotopes;     Show all 5 Subjects
Abstract:
... An O-antigen polysaccharide fraction (Ke-PS) was isolated from Komagataeibacter europaeus NBRC 3261. In addition to chemical analyses, its structure was characterized by 1D and 2D ¹H as well as ¹³C NMR spectroscopy. The polysaccharide is composed of linear disaccharide repeating unit that consists of d-galactose and d-glycero-d-manno-heptose: →7)-α-d,d-Hepp-(1 → 2)-α-d-Galp-(1 → . ...
DOI:
10.1016/j.carres.2020.107989

5. Forensic analysis of condom traces: Chemical considerations and review of the literature

Author:
Burnier, Céline; Massonnet, Geneviève
Source:
Forensic science international 2020 v.310 pp. 110255
ISSN:
0379-0738
Subject:
chemical analysis,   etc   ; forensic sciences; humans; nondestructive methods; statistics;     Show all 5 Subjects
Abstract:
... The analysis of condom traces has recently been added to the standard forensic examination protocol of sexual assault and rape cases. Several recent studies have thus focussed on the detection of condom components and classification of the chemical profiles using statistics, obtaining very promising results. The purpose of the present article is to critically review the literature regarding condom ...
DOI:
10.1016/j.forsciint.2020.110255

6. Surface-enhanced Raman spectroscopy for polychlorinated biphenyl detection: Recent developments and future prospects

Author:
Cheng, Jie; Wang, Peilong; Su, Xiao-Ou
Source:
Trends in analytical chemistry 2020 v.125 pp. 115836
ISSN:
0165-9936
Subject:
chemical analysis,   etc   ; Raman spectroscopy; carcinogenicity; monitoring; mutagens; polychlorinated biphenyls; teratogenicity;     Show all 7 Subjects
Abstract:
... Polychlorinated biphenyls (PCBs) have gained much attention for their carcinogenic, teratogenic, and mutagenic properties. Although banned in the 1970s, PCBs are still frequently found worldwide in environment, animal-origin food and natural waters. Therefore, the development of determination methods is an indispensable step for the monitoring of PCBs. Surface-enhanced Raman spectroscopy (SERS) is ...
DOI:
10.1016/j.trac.2020.115836

7. Validation of a stability-indicating HPLC-UV method for the quantification of acetazolamide in Oral-Mix and Oral-Mix SF

Author:
Gilium, Charlotte; Friciu, Mihaela; Abatzoglou, Nicolas; Leclair, Grégoire
Source:
MethodsX 2020 pp. 100844
ISSN:
2215-0161
Subject:
chemical analysis,   etc   ; acetazolamide; drugs; high performance liquid chromatography;     Show all 4 Subjects
Abstract:
... This manuscript details the modifications made to the HPLC assay method described in the USP monograph for Acetazolamide Compounded Oral Suspension.•The method was modified to allow the quantification of acetazolamide in two new suspension vehicles: Oral Mix and Oral Mix SF;•It was validated for linearity, accuracy, precision and specificity;•It was demonstrated stability-indicating and suitable f ...
DOI:
10.1016/j.mex.2020.100844
PubMed:
32211305
PubMed Central:
PMC7082594

8. Switching of Self-Assembly to Solvent-Assisted Assembly of Molecular Motor: Unveiling the Mechanisms of Dynamic Control on Solvent Exchange

Author:
Chattaraj, Krishna Gopal; Paul, Rabindranath; Paul, Sandip
Source:
Langmuir 2020 v.36 no.7 pp. 1773-1792
ISSN:
1520-5827
Subject:
chemical analysis,   etc   ; kinesin; molecular dynamics; quantum mechanics; solvents; tetrahydrofuran;     Show all 6 Subjects
Abstract:
... Natural biological molecular motors are capable of performing several biological functions, such as fuel production, mobility, transport, and many other dynamic features. Inspired by these biological motors, scientists effectively synthesized artificial molecular motors to mimic several biological functionalities. Several molecular systems, from sensitive materials to molecular motors, are essenti ...
DOI:
10.1021/acs.langmuir.9b03718

9. Chemical Analysis of Secondary Electron Emission from a Water Cathode at the Interface with a Nonthermal Plasma

Author:
Delgado, Hernan E.; Elg, Daniel T.; Bartels, David M.; Rumbach, Paul; Go, David B.
Source:
Langmuir 2020 v.36 no.5 pp. 1156-1164
ISSN:
1520-5827
Subject:
chemical analysis,   etc   ; cathodes; electrons; hydrogen; hydroxyl radicals; pH;     Show all 6 Subjects
Abstract:
... When a nonthermal plasma and a liquid form part of the same circuit, the liquid may function as a cathode, in which case electrons are emitted from the liquid into the gas to sustain the plasma. As opposed to solid electrodes, the mechanism of this emission has not been established for a liquid, even though various theories have attempted to explain it via chemical processes in the liquid phase. I ...
DOI:
10.1021/acs.langmuir.9b03654

10. Changes of asphalt fumes in hot-mix asphalt pavement recycling

Author:
Mo, Shicong; Wang, Yuhong; Xiong, Feng; Ai, Chunjin; Wang, Dawei; Tan, Giin Yu Amy
Source:
Journal of cleaner production 2020 v.258 pp. 120586
ISSN:
0959-6526
Subject:
chemical analysis,   etc   ; bitumen; ecosystem services; engineering; environmental hazards; particulates; pavements; polycyclic aromatic hydrocarbons; recycling;     Show all 9 Subjects
Abstract:
... Hot-mix asphalt pavement recycling is widely practiced for its economic and environmental benefits. Existing studies are mainly focused on the engineering properties of reclaimed asphalt pavement (RAP) materials, without considering their impacts on the generated asphalt fumes—a widely recognized environmental hazard. The effects of using RAP on asphalt fumes are systematically studied in this res ...
DOI:
10.1016/j.jclepro.2020.120586

11. Visualizing electron storage capacity distribution in biochar through silver tagging

Author:
Xin, Danhui; Barkley, Thomas; Chiu, Pei C.
Source:
Chemosphere 2020 v.248 pp. 125952
ISSN:
0045-6535
Subject:
chemical analysis,   etc   ; bioavailability; biochar; carbon; electrochemistry; electron microscopy; electrons; nanoparticles; pH; redox reactions; silver;     Show all 11 Subjects
Abstract:
... Electron storage capacity (ESC) is the capacity of a black carbon to store and reversibly donate and accept electrons in redox processes. Electrochemical and chemical analyses have shown the ESC of black carbon (e.g., plant-based biochars) was on the order of a few mmol/g. However, it remains unknown where ESC is located. The spatial distribution of ESC is important because it controls the bioacce ...
DOI:
10.1016/j.chemosphere.2020.125952

12. Establishing structure-sensitivity of ceria reducibility: real-time observations of surface-hydrogen interactions

Author:
Duchoň, Tomáš; Hackl, Johanna; Mueller, David N.; Kullgren, Jolla; Du, Dou; Senanayake, Sanjaya D.; Mouls, Caroline; Gottlob, Daniel M.; Khan, Muhammad I.; Cramm, Stefan; Veltruská, Kateřina; Matolín, Vladimír; Nemšák, Slavomír; Schneider, Claus M.
Source:
Journal of materials chemistry A 2020 v.8 no.11 pp. 5501-5507
ISSN:
2050-7496
Subject:
chemical analysis,   etc   ; adsorption; catalysts; catalytic activity; cerium; density functional theory; hydrogen; models; oxygen;     Show all 9 Subjects
Abstract:
... The first layer of atoms on an oxide catalyst provides the first sites for adsorption of reactants and the last sites before products or oxygen are desorbed. We employ a unique combination of morphological, structural, and chemical analyses of a model ceria catalyst with different surface terminations under an H₂ environment to unequivocally establish the effect of the last layer of atoms on surfa ...
DOI:
10.1039/c9ta11784a

13. Monitoring of Selected Physical and Chemical Parameters of Test Oil in the Wet Disc Brake System

Author:
Jablonický, Juraj; Simikić, Mirko; Tulík, Juraj; Tomić, Milan; Hujo, Ľubomír; Kosiba, Ján
Source:
Acta technologica agriculturae 2020 v.23 no.1 pp. 46-52
ISSN:
1338-5267
Subject:
chemical analysis,   etc   ; X-ray fluorescence spectroscopy; additives; metals; monitoring; oils; physicochemical properties; tractors; viscosity; water content;     Show all 10 Subjects
Abstract:
... Paper presented is focused on the operating measurements of a tractor wet disc brake system. Operating measurements were evaluated after tractor’s operation at 500 Mth on the 3ʳᵈ, 4ᵗʰ and 5ᵗʰ gear. Reference fluid and ecological fluid were tested during operation. In addition, work results include the evaluation of the fluid samples taken during the operational tests to monitor the tractor braking ...
DOI:
10.2478/ata-2020-0008

14. Developing front‐end devices for improved sample preparation in MS‐based proteome analysis

Author:
Doucette, Alan A.; Nickerson, Jessica L.
Source:
Journal of mass spectrometry 2020 v.55 no.3 pp. e4494
ISSN:
1076-5174
Subject:
chemical analysis,   etc   ; equipment design; instrumentation; manufacturing; mass spectrometry; proteome; proteomics; spectrometers;     Show all 8 Subjects
Abstract:
... Chemical analysis has long relied on instrumentation, from the simplest (eg, burets) to the more sophisticated (eg, mass spectrometers) to facilitate precision measurements. Regardless of their complexity, the development of a new instrumental device can be a valued approach to address problems in science. In this perspective, we outline the process of novel device design, from early phase concept ...
DOI:
10.1002/jms.4494

15. A new ternary silicide GdFe₁₋ₓSi₂ (x=0.32): preparation, crystal and electronic structure

Author:
Babizhetskyy, Volodymyr; Köhler, Jürgen; Tyvanchuk, Yuriy; Zheng, Chong
Source:
Zeitschrift für Naturforschung 2020 v.75 no.1-2 pp. 217-223
ISSN:
1865-7117
Subject:
chemical analysis,   etc   ; X-ray diffraction; crystal structure; crystallization; gadolinium; iron; oxidation; silicon;     Show all 8 Subjects
Abstract:
... The title compound was prepared from the elements by arc-melting. The crystal structure was investigated by means of single-crystal X-ray diffraction. It crystallizes in the TbFeSi₂ structure type, orthorhombic space group Cmmm, a = 4.0496(8), b = 16.416(2), c = 3.9527(6) Å, Z = 4, R1 = 0.041, wR2 = 0.11 for 207 unique reflections with Iₒ > 2 σ(Iₒ) and 19 refined parameters. The Fe position is not ...
DOI:
10.1515/znb-2019-0200

16. Ionic Liquid Stabilized 2,2,6,6-Tetramethylpiperidine 1-Oxyl Catalysis for Alcohol Oxidation

Author:
Li, Min; Klunder, Kevin; Blumenthal, Emmy; Prater, Matthew B.; Lee, Jack; Matthiesen, John E.; Minteer, Shelley D.
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.11 pp. 4489-4498
ISSN:
2168-0485
Subject:
chemical analysis,   etc   ; butanol; catalysts; catalytic activity; electrochemistry; electrodes; electrolytes; glycerol; ionic liquids; lactones; oxidation; pH; thermodynamics;     Show all 13 Subjects
Abstract:
... N-Oxyl reagents, particularly 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO), have been extensively used for alcohol oxidations. While TEMPO-mediated oxidations are kinetically and thermodynamically favorable in high-pH electrolytes, base-induced degradation often results in significant loss of catalytic activity. Herein, we demonstrate enhanced alkaline stability of a TEMPO derivative in ionic liqu ...
DOI:
10.1021/acssuschemeng.9b07650

17. The untypical high-pressure Zintl phase SrGe₆

Author:
Schwarz, Ulrich; Castillo, Rodrigo; Hübner, Julia M.; Wosylus, Aron; Prots, Yurii; Bobnar, Matej; Grin, Yuri
Source:
Zeitschrift für Naturforschung 2020 v.75 no.1-2 pp. 209-216
ISSN:
1865-7117
Subject:
chemical analysis,   etc   ; X-ray diffraction; ambient pressure; cations; chemical bonding; germanium; quantum mechanics; strontium;     Show all 8 Subjects
Abstract:
... The binary strontium germanide SrGe₆ was synthesized at high-pressure high-temperature conditions of approximately 10 GPa and typically 1400 K before quenching to ambient conditions. At ambient pressure, SrGe₆ decomposes in a monotropic fashion at T = 680(10) K into SrGe₂ and Ge, indicating its metastable character. Single-crystal X-ray diffraction data indicate that the compound SrGe₆ adopts a ne ...
DOI:
10.1515/znb-2019-0197

18. Micropollutants in treated wastewater

Author:
Rogowska, Justyna; Cieszynska-Semenowicz, Monika; Ratajczyk, Wojciech; Wolska, Lidia
Source:
Ambio 2020 v.49 no.2 pp. 487-503
ISSN:
0044-7447
Subject:
chemical analysis,   etc   ; drugs; ecosystems; ecotoxicology; effluents; humans; personal care products; risk; wastewater; wastewater treatment;     Show all 10 Subjects
Abstract:
... Compounds such as pharmaceuticals, or personal care products are only partially removed in wastewater treatment processes. Large number of these compounds and their degradation products is out of any control. A small number of compounds are covered by legal regulations. Among the compounds non-regulated by law, the target compounds, as well as non-target compounds can be distinguished. In the scie ...
DOI:
10.1007/s13280-019-01219-5
PubMed:
31292910
PubMed Central:
PMC6965340

19. Palhinosides A–H: Flavone Glucosidic Truxinate Esters with Neuroprotective Activities from Palhinhaea cernua

Author:
Li, Jing; Tan, Lei-Hong; Zou, Hui; Zou, Zhen-Xing; Long, Hong-Ping; Wang, Wen-Xuan; Xu, Ping-Sheng; Liu, Li-Fei; Xu, Kang-Ping; Tan, Gui-Shan
Source:
Journal of natural products 2020 v.83 no.2 pp. 216-222
ISSN:
1520-6025
Subject:
chemical analysis,   etc   ; carbon; esters; flavones; glucosides; glutamic acid; neuroprotective effect; spectroscopy; stereoisomers;     Show all 9 Subjects
Abstract:
... Palhinosides A–H (1–8), new flavone glucosidic truxinate esters, including β-truxinate and μ-truxinate forms, were isolated from Palhinhaea cernua. Their structures were elucidated by extensive spectroscopic methods and chemical analyses. The flavone glucoside cyclodimers possess a unique cyclobutane ring in their carbon scaffolds. Compounds 2–7 represent three pairs of stereoisomers (2/3, 4/5, 6/ ...
DOI:
10.1021/acs.jnatprod.9b00470

20. Effect of salinity on supercritical CO2 permeability of caprock in deep saline aquifers: An experimental study

Author:
Jayasekara, D.W.; Ranjith, P.G.; Wanniarachchi, W.A.M.; Rathnaweera, T.D.; Chaudhuri, A.
Source:
Energy 2020 v.191 pp. 116486
ISSN:
0360-5442
Subject:
chemical analysis,   etc   ; aquifers; carbon dioxide; cations; elemental composition; ion exchange; minerals; permeability; salinity;     Show all 9 Subjects
Abstract:
... The permanence of injected CO₂ in deep saline aquifers mainly depends on caprock permeability. Thus, the main objective of this study is to investigate the effect of salinity level in the formation fluid on permeability of siltstone when advective flow of scCO₂ is dominant. Siltstone caprock samples were fully saturated with different synthetic brines, which were similar to natural formation fluid ...
DOI:
10.1016/j.energy.2019.116486