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highperformanceliquidchromatography, etc ; acetaldehyde; acrolein; emissions factor; formaldehyde; smog pollution; tillage; China; Show all 8 Subjects
Abstract:
... Emissions of carbonyl compounds from agricultural machines cannot be ignored. Carbonyl compounds can cause the formation of ozone (O₃) and secondary organic aerosols, which can cause photochemical smog to form. In this study, 20 agricultural machines were tested using portable emission measurement system (PEMS) under real-world tillage processes. The exhaust gases were sampled using 2,4-dinitrophe ...
highperformanceliquidchromatography, etc ; anisotropy; irradiation; photoisomerization; Show all 4 Subjects
Abstract:
... Asymmetric 2,7-di-tert-butyl-10b,10c-dimethyl-2′,3′-dimethyl-pyrazino[2,3-e]dihydropyrene (DMPZ-DHP) was prepared by the annulation of diamino dihydropyrene with 2,3-butanedione. Optical resolution was achieved using chiral high-performance liquid chromatography systems after the photoisomerization of DMPZ-DHP to DMPZ-metacyclophane-diene (MCPD), and its Kuhn’s anisotropy factor (g = Δε/ε) was det ...
highperformanceliquidchromatography, etc ; pH; phytochemicals; reference standards; Show all 4 Subjects
Abstract:
... OBJECTIVES: Because the purity of the two impurities reference standard (RS) of cefathiamidine is not easy to obtain, HPLC‐PDA‐ELSD were used to determin the RRFs of cefathiamidine impurities. METHODS: Peak area correction was applied to calculate RRFs to eliminate the influence of different responses caused by the difference in pH between the two mobile phases of HPLC‐PDA and HPLC‐PDA‐ELSD. The r ...
highperformanceliquidchromatography, etc ; silica gel; zinc carbonate; Show all 3 Subjects
Abstract:
... Chiral mesostructured hydroxide zinc carbonate coated silica gel (CMHZC@S) was prepared by a hydrothermal route using amino acids as symmetry-breaking agents. CMHZC@S with three levels of hierarchical chiralities, as a chiral stationary phase (CSP), showed enantiomeric separation ability for high performance liquid chromatography (HPLC). ...
highperformanceliquidchromatography, etc ; chitosan; drugs; enantiomers; solvents; Show all 5 Subjects
Abstract:
... In the recent years, the resolution of drug enantiomers has received widespread attention in the medical field. It is of great practical significance to develop an efficient chiral separation material for drug analysis. Based on the distinct advantages of both favorable separation performance and good solvent tolerance, chitosan bis(4-methylphenylcarbamate)-(isobutylurea) was chosen as a chiral se ...
Maiara C. S. Paixão; Jessica Nardi; Charise D. Bertol; Natália Freddo; Bruna F. Vieira; Vitoria A. Rosano; Maria T. Friedrich; Luciana G. Rossato-Grando
highperformanceliquidchromatography, etc ; sewage; solid phase extraction; wastewater; Show all 4 Subjects
Abstract:
... Methylphenidate (MPH) is an important emerging pollutant found in effluents and wastewater. Thus, we aimed to develop and validate a method for detection and quantitation of MPH residues in sewage through high performance liquid chromatography coupled with photodiode array detector (LC-PDA). Here we describe a selective, accurate, precise, and valid method for determination of MPH in sewage with a ...
highperformanceliquidchromatography, etc ; drugs; photocatalysis; pollution; toxicity; wastewater; Show all 6 Subjects
Abstract:
... Pharmaceuticals are used every day in most parts of the world and great proportions of these substances are excreted unaltered or as active sub-products, posing a threat of pollution. To protect the aquatic ecosystems, innovative solutions such as photocatalysis, electrocatalysis and photoelectrocatalysis are required. In this article we provide a comprehensive review of photo- and electrocatalyti ...
highperformanceliquidchromatography, etc ; Atractylodes macrocephala; algorithms; chemometrics; markets; provenance; Show all 6 Subjects
Abstract:
... In this work, a simple and effective strategy for the determination of 12 active compounds of Atractylodes macrocephala Koidz. (AM) was proposed by using high performance liquid chromatography-diode array detection (HPLC-DAD) combined with alternating trilinear decomposition (ATLD) algorithm. Utilizing the "second-order advantage", three common problems in HPLC could be resolved, namely baseline d ...
reversed-phase highperformanceliquidchromatography, etc ; Centruroides; Scolopendra; drugs; ecology; venoms; Show all 6 Subjects
Abstract:
... As biochemical traits with clear fitness consequences, venoms serve a critical ecological role for the animals that produce them. Understanding how venoms are maintained and regenerated after use will, therefore, provide valuable insight into the ecology of venomous animals. Furthermore, most studies on venomous organisms often require removing animals from the wild and waiting extended periods of ...
highperformanceliquidchromatography, etc ; cost effectiveness; milk; separation; tandem mass spectrometry; Show all 5 Subjects
Abstract:
... Herein, an improved method for detecting the endocrine‐disrupting chemicals in milk is presented, which is based on high performance liquid chromatography tandem mass spectrometry, coupled with a quick, effective, and safe method. The linearity of the proposed method was in the range of 0.05–100 μg/L, and all correlation coefficients were ≥0.9973. At three concentration levels, the spiked recoveri ...
highperformanceliquidchromatography, etc ; ecotones; lignin; naphthalene; peat; peatlands; permafrost; tundra; Show all 8 Subjects
Abstract:
... The accumulation of polycyclic aromatic hydrocarbons (PAHs) in plants and peat of three natural subzones—forest-tundra, southern tundra, and northern tundra—is discussed. The content of polyarenes is estimated with high performance liquid chromatography. The absence of statistically significant differences in the PAH accumulation by the plants of the same species in the studied ecotones allows for ...
highperformanceliquidchromatography, etc ; Gentiana; callus; habitats; liquids; plant growth; India; Show all 7 Subjects
Abstract:
... The roots and shoots of Gentiana kurroo Royle are rich sources of gentiopicroside (GPD). The plant is used traditionally for curing many metabolic diseases. The exploitation of G. kurroo in its native habitat has placed the plant on the critically endangered list of plants in India. One of the ways of creating an alternative source of G. kurroo is through in vitro propagation. Although a number of ...
highperformanceliquidchromatography, etc ; Trigonella foenum-graecum; foams; food research; technology; Show all 5 Subjects
Abstract:
... Dioscin in Trigonella foenum-graecum was purified by foam separation combined with preparative high-performance liquid chromatography (Prep-HPLC) and the preparation method of dioscin monomer was established. Then, the structure was confirmed by FI-IR, HRMS, ¹³C-NMR and ¹H-NMR.The results showed that the method had the advantages of simple operation, short separation period and high efficiency and ...
highperformanceliquidchromatography, etc ; amyloid; fluorine; ligands; peptides; positron-emission tomography; stoichiometry; Show all 7 Subjects
Abstract:
... Amyloid imaging by positron emission tomography (PET) is an important method for diagnosing neurodegenerative disorders such as Alzheimer’s disease. Many ¹¹C- and ¹⁸F-labeled PET tracers show varying binding capacities, specificities, and affinities for their target proteins. The structural basis of these variations is poorly understood. Here we employ ¹⁹F and ¹³C solid-state NMR to investigate th ...
highperformanceliquidchromatography, etc ; Talaromyces pinophilus; liquids; phosphates; soil pH; solubilization; Indonesia; Show all 7 Subjects
Abstract:
... Sembiring M, Sabrina T. 2021. Diversity of phosphate solubilizing bacteria and fungi from andisol soil affected by the eruption of Mount Sinabung, North Sumatra, Indonesia. Biodiversitas 23: 713-719. Phosphate solubilizing microbes are present in all locations with different population levels. The eruption of Mount Sinabung in 2013 resulted in changes in soil pH and the soil’s microbial population ...
highperformanceliquidchromatography, etc ; automation; feeds; food research; monoclonal antibodies; technology; zearalenone; Show all 7 Subjects
Abstract:
... In this study, a sensitive high-performance liquid chromatography method for zearalenone determination in feeds and grains was established based on the automatic immunomagnetic bead purifier analyzer (KY-AMI-I) for the one-step sample pre-treatment. Various parameters that may affect the analytical performance were investigated. Immunomagnetic bead separation system based on a monoclonal antibody ...
reversed-phase highperformanceliquidchromatography, etc ; epoxides; methanol; silica gel; standard deviation; Show all 5 Subjects
Abstract:
... Polyimine macrocycles are a new class of organic macrocycles with cyclic structures, well-defined molecular cavities, and multiple cooperative binding sites, which have recently aroused considerable research interest in molecular recognition and separation. Herein, we report the bonding of a [3+3] chiral polyimine macrocycle (H₃L, C₇₈H₇₈N₆O₃) on thiol-functionalized silica gel using thiol-ene clic ...
highperformanceliquidchromatography, etc ; acrylamides; diet; food science; humans; markets; research; starch; India; Show all 9 Subjects
Abstract:
... The harmful effects of acrylamide (AA) are a major health concern for human beings. To find out the levels of AA content in commercial food products, 43 samples representing 3 important product categories (French fries, bakery biscuits, and branded biscuits) were procured from the local market in Allahabad, India. An assay of AA was done using HPLC-DAD. The LOD and LOQ for AA were 3.733 and 11.045 ...
reversed-phase highperformanceliquidchromatography, etc ; amides; durability; enantioselectivity; gas chromatography; lactones; liquids; Show all 7 Subjects
Abstract:
... High-performance liquid chromatography (HPLC) and gas chromatography (GC) over chiral stationary phases (CSPs) represent the most popular and highly applicable technology in the field of chiral separation, but there are currently no CSPs that can be used for both liquid and gas chromatography simultaneously. We demonstrate here that two olefin-linked covalent organic frameworks (COFs) featuring ch ...
highperformanceliquidchromatography, etc ; Ziziphus; adulterated products; food composition; honey; psicose; syrups; China; Show all 8 Subjects
Abstract:
... The content of psicose in 454 honey samples and 58 syrup samples collected from China was determined by a high-performance liquid chromatography coupled to evaporative light scattering detection (HPLC-ELSD) method. Psicose was not detected in any honey samples except for some Jujube honeys, and psicose was detected in 23 of 53 of Jujube honeys, with an average content of 0.21 g/100 g. The detectio ...