Chemistry and geology of coal: nature, composition, coking, gasification, liquefaction, production of chemicals, formation, peatification, coalification, coal types, and ranks

As probably the most complex natural (geological) material, as well as a parent of the industrial revolution and the most important source of heat and electricity in the world, coal has attracted and continues to attract special attention of scientists and the entire world population. In this context, this lecture text is intended to provide both chemistry and geology students as well as teachers of courses on the chemistry and geology of coal with a solid background of the chemistry and geology of coal. Various aspects of coal chemistry are covered, including the nature of coal, its composition, coking, gasification, liquefaction and production of chemicals. Coal geology concerns major eras of coal formation as well as the processes of peatification, coalification and the chemical processes of coalification, coal types and their properties, coal lithotypes and coal ranks. Each of these topics is an important subject in its own, and this text is aimed to give only a brief overview of each, emphasising the relationship between the geology and chemistry of coal

Chemical and mineralogical characterization of volcanic glass (perlite) from Republic of Macedonia

Characterization of the volcanic glass (perlite) from Bitola region (Republic of Macedonia) was performed by the chemical, XRPD, IR and SEM analyses. The chemical analysis shows that the volcanic glass (perlite) represents an acidic volcanic rock with high percentage of SiO2 (72.45%), high percentage of alkali metal oxides (4.21% K2O, 3.56 % Na2O), and loss on ignition 3.54%. Results of the XRPD analyses indicate the presence of the amorphous phase with small presence of crystalline phases (feldspars, quartz, cristobalite and magnetite). SEM examinations point to the glassy structure with presence of pores with 50-100 μm in size

Approaches in evaluation of freeze-dried antibody conjugates

The presented experience was in freeze-drying of monoclonal antibody – rituximab, conjugated with three types of bifunctional chelating agents, p-SCN-Bn-DOTA, p-SCN-Bn-DTPA, and 1B4M-DTPA, and evaluation of possible changes in post-freeze-drying phase, using SDS-PAGE electrophoresis, FT-IR and Raman spectroscopy techniques

Intriguing minerals: quartz and its polymorphic modifcations

This lecture text condenses the characteristics of quartz and its rich palette of varieties. The mineralogy and crystallography of quartz and its forms, the origin of its colors, and their important physical and chemical characteristics are discussed. The geological occurrence of quartz and its varieties in the world is also presented, with special attention to North Macedonia. Their applications in various industries are also included. Knowledge of the specifc properties of SiO2 minerals is indispen�sable for understanding and reconstruction of geological processes, as well as for specifc technical application

Micro-Raman Spectroscopy for Detection of Label-Free and Oil Red O Labeled PEGylated Nanoliposomes in hCmec/D3 Cell Internalization Studies

Rapid development of nanomedicines necessitates advancement in internalization techniques which can accurately distinguish between the complex environments of cells and nanocarriers. Internalization (or endocytosis) studies of oil red O labeled and label-free PEGylated-lecithin/cholesterol nanoliposomes was performed using micro-Raman spectroscopy. The C.O stretching vibrations and CCH scissoring bendings of naphthalene ring around 1225 cm.1 as well as the N=N stretching vibrations at 1377 cm.1 are prominent peaks absent from the label-free spectra which can be used for detection of internalized oil red O labeled nanoliposomes. Suitability of oil red O as a liposome marker was confirmed by stability studies of the incorporated dye and automated fluorescence cell counting. The C.C stretching region with a prominent wide band centered at 1080 cm.1 indicative of larger gauche conformer content typical for the lecithin-cholesterol nanoliposomes and the strong maximum at 980 cm.1 associated with O.C.C.N+ stretching vibrations of the liposome polar head groups are important for studying label-free nanoliposome cell internalization

Diatomite – evaluation of physico-mechanical, chemical, mineralogical and thermal properties

Diatomite is one of the most intensively examined raw materials in the materials industry with a broad range of various applications. The diatomite sample, collected from Vitačevo plateau in the vicinity of Kavadarci, was fully characterized by means of physical-mechanical, chemical, XRPD, SEM, TEM, DTA/TGA and IR techniques. The physical-mechanical features pointed out to soft, light, white to gray rock with shell-like structure exhibiting compressive strength from 4.65–4.88 MPa in dry form, whereas the total porosity ranges 70–72% and the density is 2.06–2.09 g/cm3. The chemical analysis of the diatomite revealed that SiO2 content exceeds 91%. The results from the X-ray powder diffraction indicate predominant amorphous SiO2 phase associated with minor presence of crystalline quartz, muscovite, chlorites and plagioclase. The IR spectrum of the diatomite manifested characteristic bands for amorphous silica at 799 cm–1 and 1101 cm–1. DTA/TGA results display great thermal stability of the sample remaining amorphous up to 1050ºC whereas the SEM analysis determined the morphology, surface characteristics and the nanometric pores in the raw material. Thus, the studied diatomite is classified as a natural nanomaterial that is suitable for broad application in various construction materials, refractory ceramics, special oxide ceramics, and also finds potential use in filtering, adsorbent, catalysts, food and pharmaceutical industries

Chemical, mineralogical and structural features of native and expanded perlite from Macedonia

The physico-mechanical, chemical and mineralogical characteristics of volcanic glass (perlite) from the Mariovo region (Macedonia) as well as the mineralogical changes that occur during its thermal treatment were investigated to demonstrate its utilization for industrial use. The native perlite was characterized by chemical analysis, X-ray powder diffraction (XRPD), infrared (IR) spectroscopy, thermal analysis (TGA/DTA), scanning electron microscopy (SEM-EDX), transmission electron microscopy (TEM), and solid- state NMR. The chemical examination suggests that the perlite represents an acidic volcanic rock with a high percentage of SiO2 (72.45%), high in alkali metal oxides (4.21 wt.% K2O, 3.56 wt.% Na2O), with a loss of ignition 3.54 wt.%. Results from the XRPD indicated major amorphous behaviour, with low amounts of feldspars, quartz, and cristobalite. SEM examinations revealed glassy structure with presence of certain pores (dimensions ranging from 50–100 μm). The determined expansion coefficient was 20 times its original volume. XRPD of expanded perlite compared to the native perlite depicted new intensive peaks of cristobalite. SEM and TEM revealed irregular morphology with broken or ragged edges. On the basis of the chemical and mineralogical composition, the studied perlite is classified as an appropriate material suitable as ceramic flux to lower the sintering temperature.</p

The restored opus sectile panel from the luxurious episcopal residence in the ancient city of Stobi– mineralogical and chemical findings

Samples from the opus sectile panel excavated from the Episcopal Residence building at the archaeological site of Stobi were examined using X-ray powder diffraction, SEM-EDS, and Raman spectroscopy. The analyzed samples, exhibiting plentiful color and surface variations, comprise the reconstructed sectile panel as well as represent the in situ ground remains. The complementary techniques revealed dominant amorphous phase in five samples, whereas the remaining seven specimens confirmed the presence of magnesite, quartz, dolomite, ankerite, cuprite, wüstite, and hematite. The work represents the first systematic attempt to determine the mineral phases in the restored opus sectile panel, assembled by decorative minerals forming a geometric net of polychrome crosses. Furthermore, the mineral characterization has revealed an origin of mineral species not typical for Macedonian terrain (ankerite, wüstite, cuprite, transparent quartz) that lead to the conclusion that the samples were likely imported from other early-Christian communities

Investigation of p-SCN-Bn-DOTA-trastuzumab labeled with radioactive and non-radioactive lutetium and yttrium: a crucial step for future applications

The significance lies in preparing stable, trastuzumab-immunoconjugate through the utilization of non-radioactive LuCl3 and YCl3, via p-SCN-Bn-DOTA. This approach is crucial to determine potential physicochemical alterations in immunoconjugate structure following metal binding. Post-conjugation, employing a 1:20 molar ratio, freeze-drying was performed to obtain stable immunoconjugates for subsequent analysis. Several chemical methods were employed to characterize antibody stability and retained immunoreactivity within the formulated immunoconjugates. Proof of protein integrity came from SDS-PAGE electrophoresis, with uniform fragment intensities (25 kDa for light chain, 50 kDa for heavy chain) indicating antibody non-degradation (1). IR and Raman spectroscopy verified secondary structural changes, with the presence of characteristic amide bands in both spectra indicating the retention of native secondary structure (2). Employing MALDI-TOF-MS, 4.9 p-SCN-Bn-DOTA molecules were determined per antibody molecule. The promising outcomes from non-radioactive labeling provide an opportunity for potential labeling with radioactive lutetium-177 and yttrium-90, each with a specific activity of 200 µCi/mL. Radioisotopes were incubated with p-SCN-Bn-DOTA-trastuzumab for an hour at 40 ºC. Evaluation of radiochemical purity and stability was conducted using the ITLC-SG system. Optimal mobile phases, specifically 0.4 M methanol:sodium acetate (1:1) for yttrium-90 and 0.9% NaCl for lutetium-177, facilitated thorough examination. Remarkable radiolabeling efficiency was achieved, >96% for yttrium-90 and >99% for lutetium-177. Stability assessments after 72 hours demonstrated greater stability in 177Lu-p-SCN-Bn-DOTA-trastuzumab (<1.5% lutetium-177 release) compared to the 90Y-labeled counterpart (<17% yttrium-90 release). This study demonstrates the successful development of radioimmunoconjugates, positioning this agent for potential application in vivo investigations

Fabrication of Ceramic Monoliths from Diatomaceous Earth: Effects of Calcination Temperature on Silica Phase Transformation

The raw diatomaceous earth from the vicinity of Bitola (North Macedonia) showed low bulk density (0.61–0.69 g/cm3), high-water absorption (75–81%) and porosity (66–72%). The chemical composition was determined with ICP-MS, revealing the following results for the diatomaceous earth: SiO2 (63.69 wt%), Al2O3 (11.79 wt%), Fe2O3 (5.95 wt%), MnO (0.15 wt%), TiO2 (0.65 wt%), CaO (1.51 wt%), MgO (2.24 wt%), P2O5 (0.13 wt%), K2O (1.64 wt%), Na2O (0.93 wt%), LOI (11.21 wt%). XRPD data of the examined sample of clayey diatomite mainly depicted crystalline behavior with a small presence of amorphous phase. The crystalline mineral phases mainly comprise: silica (quartz), feldspars (plagioclase), mica (muscovite), chlorites and dolomite. SEM and TEM results show cased presence of micro- and nanostructures with pores ranging from 250 to 600 nm. The clayey diatomite was sintered at three temperatures (900, 1000 and 1100ºC) for a period of 1 h. XRPD of the sintered samples at 1100ºC showed certain thermal stability and formation of new phases (mullite and tridymite) that makes the analyzed diatomaceous earth suitable for production of various types of ceramic, construction and thermal insulating materials