キレート作用および還元作用により褐炭から溶出する有機物と金属元素の特徴

The identification and localization of organic components in the complex stratigraphy of paintings play a crucial role in studies of painting techniques and authentication, restoration, and conservation of artworks. Much scientific effort has been expended for the development of analytical approaches suitable for the investigation and characterization of organic substances, allowing high sensitivity, specificity, and spatial resolution. Proteins (e.g., ovalbumin, casein, and collagen from different animal sources) are one of the classes of organic substances most widely used as painting materials. The analytical techniques commonly used for their analysis (micro Fourier transform infrared spectroscopy, chromatographic techniques, and proteomic approaches) have limits related to the lack of specificity or to the absence of information concerning the stratigraphic localization of the detected proteins. Immunological techniques are a promising alternative approach for the characterization of proteins in artworks. Thanks to the high specificity of antigen-antibody reactions, these techniques are widely used for the analysis of proteins in bioanalytical and clinical chemistry and recently they have been successfully applied in the field of science for conservation of cultural heritage. The present research aimed to develop an ultrasensitive chemiluminescent immunochemical procedure for the simultaneous localization of ovalbumin and bovine casein (two common proteins found in binding media or varnishes of artistic and archaeological samples) in resin-embedded painting micro cross-sections. The possibility of performing the simultaneous identification of different proteins in painting cross-sections is of particular relevance in the field of cultural heritage because samples are often small and available in a limited number; therefore, the maximum amount of information must be obtained from each of them.

Determination of phosphorous in organic compounds and metal complexes by inductively-coupled plasma atomic emission spectrometry

Chapter 13 - Green extraction approaches utilizing graphene and graphene oxide derivatives in environmental analysis

A unit world model that has the potential to be used for the hazard assessment of both metal ions and organic chemicals is described and discussed, with an emphasis on the problems that arise when treating metal ions. It is based on the steady-state equilibrium criterion model that is designed to simulate the fate of organic chemicals in a 100,000-km(2) region and comprises four well-mixed compartments: Air, water, soil, and sediment. To be applicable to metal ions, modifications are required. The single soil and sediment layers should be replaced by two layers to accommodate aerobic and anaerobic conditions. The more complex and variable partitioning of metals resulting from dependence on pH, redox conditions, ionic oxidation state, and presence of sulfide also must be addressed, but preferably in a separate geochemical model, because these factors can result in nonlinearity. For metals, a dynamic as well as a steady-state model is desirable. It is shown that the resulting model can be applied to both organics and metals. Rather than seeking to apply the hazard criterion of persistence to metal ions, the model can be used to deduce a critical loading that results in a defined toxic end point, thus integrating the hazard criteria of persistence, toxicity, and possibly, bioaccumulation. This approach is applied illustratively to naphthalene as a typical organic substance and to four environmentally relevant metal ions. Results are discussed and recommendations made for further development. Specifically, the absence of metal degradation can result in large, steady-state quantities in soils and sediments corresponding to residence times of many centuries. Consequently, the dynamic calculations are more relevant for fate assessments of metals over a period of years, and more focus on the aquatic environment is justified.

The synthesis and characterization of PTCDA-Co(II), and PTCDA-La(III) fluorescent MOFs

Characterization of biogas and biomethane trace compounds: A critical review of advances in in situ sampling and preconcentration techniques

Two manganese peroxidases (MnPs), MnP1 and MnP2, and a laccase, Lac1, were purified from Trametes polyzona KU-RNW027. Both MnPs showed high stability in organic solvents which triggered their activities. Metal ions activated both MnPs at certain concentrations. The two MnPs and Lac1, played important roles in dye degradation and pharmaceutical products deactivation in a redox mediator-free system. They completely degraded Remazol brilliant blue (25 mg/L) in 10–30 min and showed high degradation activities to Remazol navy blue and Remazol brilliant yellow, while Lac1 could remove 75% of Remazol red. These three purified enzymes effectively deactivated tetracycline, doxycycline, amoxicillin, and ciprofloxacin. Optimal reaction conditions were 50 °C and pH 4.5. The two MnPs were activated by organic solvents and metal ions, indicating the efficacy of using T. polyzona KU-RNW027 for bioremediation of aromatic compounds in environments polluted with organic solvents and metal ions with no need for redox mediator supplements.

As a fascinating two-dimensional (2D) layered inorganic ion exchange material, zirconium phosphate (hereafter ZrP) has drawn interdisciplinary attention as an ion exchange material and a competent host for surface functionalization and intercalation. This is due to its captivating properties such as simple synthesis procedure, excellent ion-exchange capacity, excellent chemical, thermal, and radiolytic stability, tunable interlayer gallery, and good biocompatibility. Among all the well-known phases of ZrP, we restrict our discussion only to the alpha (α-ZrP) and gamma (γ-ZrP) phases for their efficient ion exchange performance and more tunable interlayer spacing. This review summarizes a panorama of the recent research progress on the synthesis, intercalation, and surface functionalization of ZrP with organic molecules, metal complexes, and metal ions for the design and fabrication of self-assembled monolayers, layer-by-layer assemblies, and nanocomposites. Within the confined gallery microenvironment of ZrP, usual molecules behave unusually with dramatic enhancement in the photophysical properties. The intercalation of metal complexes and their fascinating electronic properties will also be comprehensively highlighted in this review. Furthermore, for the first time, a cutting-edge advancement (2010 onward) of the versatile adsorption performance of ZrP-based materials for the uptake of toxic metal ions which include nuclear waste-related metal ions, heavy metal ions, and rare earth ions will be presented in detail. Last but not least, the review will conclude with the summary and future directions, which will provide new research opportunities for the development of ZrP based sustainable heterofunctional material.

Modifying organic coatings to provide corrosion resistance—Part III: Organic additives and conducting polymers

Luteolin is a flavonoid compound widely found in vegetables, fruits, and medicinal plants. In this study, the reaction conditions for luteolin and five metal ions (Ca2+, Mg2+, Zn2+, Fe3+, and Cu2+) to form complexes in hot water were optimized, which was at a molar ratio of 1 : 1 for luteolin and metal ions at 90°C in a volume of 20 mL for 2 h, and the ability of luteolin to form complexes with Cu2+ was the strongest. The DPPH scavenging test showed that luteolin exerted a dose-dependent effect on the clearance of free radicals; luteolin-Cu2+ complexes and luteolin-Fe3+ complexes accentuated the clearance of free radicals. Furthermore, we used high performance liquid chromatography (HPLC) to analyze luteolin in samples from two medicinal plants, obtained from the dissolution of aqueous extracts in two different solvents. The results showed that the peak areas for luteolin in the samples dissolved in 20% formic acid-methanol were significantly larger than those from the samples dissolved in methanol alone, with increases in the peak area being 135.6% (Lonicerae Japonicae Flos), and 161.16% (Huangshan wild chrysanthemum). The aforementioned results indicate that complexes formed from organic compounds and metal ions are present in the decoction of a plant.

Chapter 4 Early Diagenesis of Sugars and Amino Acids in Sediments

Prediction of fluorophilicity of organic and transition metal compounds using molecular surface areas

The increasing prevalence of tattoos and the frequent occurrence of adverse skin reactions, particularly from colored inks, highlight the urgent need for reliable analytical methods to identify potentially harmful substances in tattoo inks and tattooed skin. In this study, a novel, laser-based technique enabling combined molecular and elemental analysis is presented: Laser Ablation hyphenated to Atmospheric Pressure Chemical Ionization-Mass Spectrometry (LA-APCI-MS) and Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS/APCI-MS). This instrumental setup allows the simultaneous detection of organic and inorganic pigments as well as their metallic contaminants directly in solid samples. A newly developed spectral pigment libraries based on MS1 and MS2 data enables precise identification of organic pigments within complex matrices such as inks or skin sections. Using five commercially available tattoo inks, this new technique reliably identified nondeclared or even prohibited organic pigments and different metals. In skin biopsies from red tattoos with adverse reactions, different organic pigments and metals were localized via bioimaging, revealing distribution patterns that may help to uncover the causes of allergic responses. The introduced LA-ICP-MS/APCI-MS technique offers a rapid and powerful approach to obtain complementary information on organic pigments, inorganic compounds, and metals from a single sample. As such, it represents a significant advancement for investigating tattoo-related side effects, supporting risk assessment, and ensuring regulatory compliance.

The recently developed Diffusion Gradient in Thin-films (DGT) technique is based on a simple device that accumulates metals in situ, over time in a Na resin gel. Metal ions diffuse through a hydrogel membrane and are rapidly bound by the resin. The many advantages associated with the DGT technique (simplicity, in situ technique, low detection limits, and ability to measure many metals) have lead to its rapid application in aquatic environments. Caveats have been recognized with the DGT technique when it is used in aquatic environments. These include: the ability of strongly complexed organic-metal molecules to diffuse through the hydrogel and become complexed by the resin gel, and in freshwater lakes with a low concentration of cations (Σ [cations] ≤ 2 × 10 -4 M), it is hypothesized that the diffusion coefficient of metal ions entering the DGT device increases. Both of these caveats overestimate the concentrations of labile inorganic metals in the deployment solution. The hypothesis that deploying DGT devices equipped with two different hydrogel formulations ("open" and "tight") will provide reasonable measurements of DGT-labile "organic" and "inorganic" concentrations of Mn, Cd and Pb was tested in the field. DGT devices were deployed in three lakes (Lake Tantare, Lake 8t. Joseph and Lake Memphremagog). To compare the responses of the DGT devices with the total dissolved metal concentration (< 0.20 um) of each lake, in situ dialysis samplers were deployed simultaneously. Overestimation of DGT-labile "inorganic" concentrations of Mn and Pb, and overestimation of DGT-labile "organic" Cd was observed when compared to the measured total dissolved metal concentrations in the lakes. The hypothesis that DGT devices equipped with a Ca form of the resin gel (as an alternative to the sodium based resin gel in the DGT device) will reasonably measure Mn, Cd and Pb labile metal concentrations in freshwater lakes with low cation concentrations was tested. DGT devices with the Ca form of the resin gel were deployed in Lake Tantare, Lake 8t. Joseph and Lake Memphremagog. Overestimation of DGT-labile metal concentrations of Mn, Cd and Pb were observed with the Ca resin gel in the lakes when compared to the measured total dissolved concentrations. The implication of these findings is that the DGT technique should not be used in freshwaters with low cation concentrations (Σ [cations] ≤ 2 × 10 -4 M), typical of lakes found in the Canadian environment, until the caveats of the technique have been resolved. Extreme caution should be used when drawing conclusions regarding the concentrations of inorganic and organic metal species, since it has been found the DGT devices with the two different hydrogel formulations overestimate the inorganic metal concentration relative to the organic metal concentration in aquatic environments.

Four (BEDT‐TTF)4A[M(C2O4)3]·DMF (DMF = dimethylformamide) salts of the organic donor molecule bis(ethylenedithio)tetrathiafulvalene (BEDT‐TTF) with metal oxalate anions, where A = (NH4, K), M = Cr (1); A = NH4, M = Fe (2); A = K, M = Cr (3); and A = NH4, M = Cr (3′) were prepared by electrocrystallization. These salts were characterized by single‐crystal X‐ray diffraction, electron spin resonance (ESR) spectroscopy, electrical resistance measurements, and electronic band structure calculations. The structures (with space group C2/c) consist of alternating β″‐type layers of BEDT‐TTF and an approximately hexagonal network formed by the A+ cation and the metal, with the solvent molecule, DMF, occupying hexagonal cavities in the anion layer. All of the salts are two‐dimensional organic metals down to 4.2 K and do not exhibit superconductivity. Their electronic band structure is similar to that of the known organic superconductor β″‐(BEDT‐TTF)4H3O[Fe(C2O4)3]·BN. The ESR spectra of salts 1 and 3′ are characterized by two resonances, one of Gaussian shape arising from the 3d localized electrons of Cr3+ and the other of Lorentzian (and Dysonian) shape due to the conduction electrons in the organic layers. On the basis of the calculated Fermi surfaces it is suggested that these salts could exhibit an interesting magnetoresistance behavior if disorder does not prevent the observation of the Shubnikov‐de Haas oscillations.