Diversity of Pyrite-Hosted Solid Inclusions and their Metallogenic Implications—A Case Study from the Myszków Mo–Cu–W Porphyry Deposit (the Kraków–Lubliniec Fault Zone, Poland)

Pyrite from the central part of the Myszków porphyry deposit in Poland was investigated using a combination of reflected and transmitted polarizing microscopy, back-scattered imaging with energy-dispersive X-ray spectroscopy, and Raman micro-spectroscopy. Five generations of pyrite (I–V) found in hydrothermal veins were distinguished, differing in morphology, microtexture, and the types and amounts of solid inclusions. In general, pyrite hosts a diversity of mineral inclusions, including both gangue and ore phases, i.e., chlorite, quartz, monazite, cerianite-(Ce), xenotime, K-feldspars, albite, sericite, barite, magnetite, chalcopyrite, galena, sphalerite, bastnaesite (Ce), bismuthinite, native silver, cassiterite, rutile, anatase, and aikinite-group species. The presence of inclusions is good evidence of various stages of the evolution of the hydrothermal lode system ranging from high- to low-temperature conditions. During the formation of stockworks, some fluctuations in the physicochemical conditions of mineralizing fluids were indicated by the occurrence of cassiterite formed from acidic, reducing solutions, and hematite hosted in xenotime or REE phases found in pyrite, which signal more oxidizing conditions. Periodically, some episodes of boiling in the hydrothermal, porphyry-related system were recorded. They were mainly evidenced by the presence of (1) lattice-bladed calcite found in the close vicinity of pyrite II, (2) irregular grain edges of pyrite I, (3) clustered micropores in pyrite I, and (4) the variety of mineral inclusions hosted in I and II generations of pyrite.

Archaeometric evidence for the earliest exploitation of lignite from the bronze age Eastern Mediterranean

This paper presents the earliest evidence for the exploitation of lignite (brown coal) in Europe and sheds new light on the use of combustion fuel sources in the 2nd millennium BCE Eastern Mediterranean. We applied Thermal Desorption/Pyrolysis–Gas Chromatography-Mass Spectrometry and Polarizing Microscopy to the dental calculus of 67 individuals and we identified clear evidence for combustion markers embedded within this calculus. In contrast to the scant evidence for combustion markers within the calculus samples from Egypt, all other individuals show the inhalation of smoke from fires burning wood identified as Pinaceae, in addition to hardwood, such as oak and olive, and/or dung. Importantly, individuals from the Palatial Period at the Mycenaean citadel of Tiryns and the Cretan harbour site of Chania also show the inhalation of fire-smoke from lignite, consistent with the chemical signature of sources in the northwestern Peloponnese and Western Crete respectively. This first evidence for lignite exploitation was likely connected to and at the same time enabled Late Bronze Age Aegean metal and pottery production, significantly by both male and female individuals.

Polychromatic polarization: Boosting the capabilities of the good old petrographic microscope

Polychromatic polarizing microscopy (PPM) is a new optical technique that allows for the inspection of materials with low birefringence, which produces retardance between 1 nm and 300 nm. In this region, where minerals display interference colors in the near-black to gray scale and where observations by conventional microscopy are limited or hampered, PPM produces a full spectrum color palette in which the hue depends on orientation of the slow axis. We applied PPM to ordinary 30 μm rock thin sections, with particular interest in the subtle birefringence of garnet due both to non-isotropic growth or to strain induced by external stresses or inclusions. The PPM produces striking, colorful images that highlight various types of microstructures that are virtually undetectable by conventional polarizing microscopy. PPM opens new avenues for microstructural analysis of geological materials. The direct detection and imaging of microstructures will provide a fast, non-destructive, and inexpensive alternative (or complement) to time-consuming and more costly scanning electron microscope–based analyses such as electron backscatter diffraction. This powerful imaging method provides a quick and better texturally constrained basis for locating targets for cutting-edge applications such as focused ion beam-transmission electron microscopy or atom probe tomography.

Thermotropic Copolyesters Based on Polyethylene Terephthalate and 4-Hydroxybenzoic Acid for High Modulus Fibers

The copolyesters derived from dimethyl ester of terephthalic acid, ethylene glycol, and 4-hydroxybenzoic acid (HBA) have been synthesized via catalytically promoted polycondensation omitting the acetylation step. FTIR spectroscopy results have evidenced an insertion of HBA along a polymer backbone. Of note, thermal gravimetric analysis has shown that the HBA moieties substantially improved the thermal stability of polyesters. As found by differential scanning calorimetry and polarizing microscopy, the copolyesters are capable of forming an anisotropic phase in a temperature range of 150-170 °C. Additionally, the free surface energy of the samples was determined to evaluate the compatibility of thermotropic copolyesters with other high-molecular compounds.

MO066CONGO RED DOT TEST AS A DIAGNOSTIC TOOL FOR RENAL AMYLOIDOSIS IN PATIENTS WITH NEPHROTIC SYNDROME

Background and Aims Amyloidosis is a serious mostly systemic disease caused by the deposition of abnormal proteins with a cross-β-sheet conformation in tissues and predominantly affecting kidneys among other organs that are associated with inferior renal outcome. Nephrotic syndrome is a common clinical manifestation of renal amyloidosis (RA) among other primary glomerulopathies. Nowadays there is a lack of non-invasive diagnostic tools for screening RA. The aim of this pilot study was to investigate the Congo Red Dot (CRD) test supplemented with polarizing microscopy as a non-invasive technique for detecting RA in patients with nephrotic syndrome. Method In this cross-sectional study, we enrolled patients with nephrotic syndrome (NS, n = 41, aged 52±12 years, 48.8% of males) and healthy individuals without proteinuria for control group (CG, n = 32, aged 45±18 years, 45.5% of males). The first-morning urine samples from all included persons were used for the CRD test. In all cases the protein-creatinine ratio (PCR) was assessed at 24-hour urine collection as well as estimated glomerular filtration rate (eGFR) using CKD-EPI formula. Kidney biopsy was carried out for morphological verification of diagnosis in all patients with nephrotic syndrome. For the Congo Red Dot test, 4 µl of Congo red dye solution (CR) was mixed with 2 µl of a sample of the patient's first-morning urine sample. This mixture was applied in duplicates onto a nitrocellulose membrane (0.45 µm). To quantify the Congo Red Retention (CRR, %), which means the staining intensity the membrane was washed in ascending series of ethanol concentrations and photographed under constant conditions before and after washing in the specially designed photo camera. The CRR was determined as the ratio of the average brightness for two spots on the membrane after and before washing in ethanol and calculated using the ImageJ software. For polarizing microscopy urine samples were centrifuged at 1500 g for 15 minutes at +4°C, the supernatant was removed, 5 µl of CR was added to the sediment and 10 µl was applied to a histological slide, and viewed under polarized light. Data are presented as median and interquartile range (M (25%; 75%)). To assess the significance of differences between groups, the nonparametric Mann-Whitney test was used. Spearman's correlation analysis was used to investigate the relationships between the variables. Receiving operating characteristic (ROC) curve was generated to assess the utility of CRR in prediction of RA. Results The CRR in the NS group (42.2% (26.8; 74.2)) significantly differs from the CRR in the CG group (0.0%), p<0.001. PCR in the NS group was 4.8 g/g (2.2; 11.2). The examples of CRD test results are shown in Figure 1a. By morphological diagnosis, patients were divided into two groups: renal amyloidosis (RA, n = 16, aged 58.3±7.5 years, 50% of males) and non-amyloid variant of nephropathy (NN, n = 25, aged 48.6±12.1 years, 48% of males). There was no significant difference between CRR in RA (71.6% (15.0; 91.8)) and NN (41.7% (27.5; 70.4), p=0.41 as well as between PCR (6.5 g/g (1.4; 15.4) in RA and 3.6 g/g (1.9; 10.4) in NN, p=0.34). Correlation between CRR and PCR in the NN (r=0.722, p<0.0001) and RA (r=0.605, p=0.013) was determined. ROC-analysis showed that threshold value for the diagnosis of RA can be taken as CRR=33.5% with sensitivity 68.8% and specificity 68.4% (Figure 1b). Despite the absence of differences in the CRR, polarization microscopy showed specific apple-green birefringence of aggregates bound with CR in the sample of patient with AL-amyloidosis (Figure 2 a, b) contrary to the sample of patient with IgA-nephropathy (Figure 2 c, d). Conclusion Preliminary results suggest that CRD test supplemented with polarizing microscopy could be used for RA screening in patients with nephrotic syndrome but require further validation as far as congophilia of urine samples from patients with non-amyloid nephropathy also presents.

ASSESSMENT OF DETERIORATION PROCESS IN EXPOSED CARVED LIMESTONE FALSE DOOR OF ABUSIR ARCHAEOLOGICAL AREA

Carved limestone false door dating back to the late Sixth Dynasty or the First Intermediate Period in Abusir archaeological area suffers from many physiochemical and mechanical deterioration factors, which lead to various deterioration phenomena, such as distort the carvings, decorations, the disappearance of paint, cracks in different depths, and salt calcification. It was found in the fill of Shaft 5 in the tomb AS 79 at Abusir South, Excav. No. 9/AS79/2015 and located in the storeroom of Czech Excavation in Abusir area. The current work aims to study the type of limestone which the false door is made of, and to know if there were colors on the false door or not, also to know if there were deterioration mechanisms that affect the carved limestone false doors of Abusir to evaluate the deterioration ratio in stone structure and the effects of surrounding environmental factors on stone. The investigation and characterization processes of archaeological limestone samples were carried out by polarizing microscopy (PLM), optical microscopy (OM), scanning electron microscopy (SEM-EDX) micro-analysis system, X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier transform infrared spectroscopy (FTIR). The results revealed that the limestone material of the false door belongs to micrite limestone with very fine grains and needs to be conserved.

Influence of 4-(2-S(+)-Methylbutyloxy)Benzoic Acid on Mesomorphic and Physico-Chemical Properties of 4-Butyl-4'-Octanoyloxyazobenzene

Mesomorphic, optical, dielectric, and orientation properties of nematic liquid crystal 4-butyl-4'-octanoyloxyazobenzene doped with chiral 4-(2-S(+)-methylbutyloxy)benzoic acid have been studied. The clearing temperatures of the mixtures were measured by polarizing microscopy. An estimation of the mesophase destabilization with the introduction of the dopant was carried out. The helix pitch of the induced chiral nematic mesophase was measured. The effect of the chiral dopant on anisotropic characteristics of the mesophase has been studied. An insignificant increase in the optical and dielectric anisotropy is associated with the formation of liquid crystal – dopant supermolecules due to hydrogen bonds –COOH…OCO–.

Improved Water-Tree Resistances of SEBS/PP Semi-Crystalline Composites under Crystallization Modifications

Water-tree resistances of styrene block copolymer/polypropylene (SEBS/PP) composites are investigated by characterizing crystallization structures in correlation with the dynamic mechanical properties to elucidate the micro-structure mechanism of improving insulation performances, in which the accelerated aging experiments of water trees are performed with water-knife electrodes. The water-tree morphology in spherulites, melt-crystallization characteristics and lamella structures of the composite materials are observed and analyzed by polarizing microscopy (PLM), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), respectively. Dynamic relaxation and stress-strain characteristics are specifically studied by means of a dynamic thermomechanical analyzer (DMA) and electronic tension machine, respectively. No water-tree aging occurs in both the highly crystalline PP and the noncrystalline SEBS elastomer, while the water trees arising in SEBS/PP composites still has a significantly lower size than that in low-density polyethylene (LDPE). Compared with LDPE, the PP matrix of the SEBS/PP composite represent a higher crystallinity with a larger crystallization size in consistence with its higher mechanical strength and lower dynamic relaxation loss. SEBS molecules agglomerate as a “island” phase, and PP molecules crystallize into thin and short lamellae in composites, leading to the blurred spherulite boundary and the appreciable slips between lamellae under external force. The high crystallinity of the PP matrix and the strong resistance to slips between lamellae in the SEBS/PP composite essentially account for the remarkable inhibition on water-tree growth.

New azobenzene liquid crystal with dihydropyrazole heterocycle and photoisomerization studies

New azobenzene derivatives with dihydropyrazole heterocycle have been prepared and characterized. According to thermal polarizing microscopy and differential scanning calorimetry studies, the compounds consisting of four linearly linked rings and a long alkoxy chain on the azobenzene side ( 3a-8 and 3a-14 ) displayed no liquid crystal properties. When the length of mesogenic unit increased to five rings, except for compound 5a-8 , all compounds from 5a-10 to 5a-16 containing a long chain of 10–16 carbon atoms on the side of ester group displayed liquid crystalline properties, and the mesogenic domain gradually narrowed with increase of the chain length. However, in the case of the molecule with long alkoxy chains on both sides, only 5c-16 with a long chain of 16 carbon atoms exhibited liquid crystal behaviour. In addition, these azo compounds underwent isomerization from E to Z under ultraviolet irradiation and then thermal back relaxation slowly in the dark, which can be recycled many times.