scholarly journals Use of thermal analysis for the detection of calcium oxalate in selected forms of plastering exposed to the effects of Serpula lacrymans

2021 ◽  
Vol 61 (4) ◽  
pp. 511-515
Author(s):  
Drahomíra Cígler Žofková ◽  
Jiří Frankl ◽  
Dita Frankeová

The article discusses the interaction of metabolic products of a wood-destroying fungus of the dry rot species (Serpula lacrymans (Wulfen) P. Karst.) with a commonly used lime mortar. Mortar samples used in the presented experiment were made mostly in laboratory conditions so as to make it possible to set input conditions and to determine initial properties of the examined samples. Matured lime mortar samples were placed in cultivation boxes with a growth of Serpula lacrymans and exposed to its action for a predetermined period of time. For a comparison, mortar samples taken “in situ” from real structures were also subjected to the experiment. The examined samples were subjected to a thermal analysis and a comparative measurement by infrared spectroscopy (FTIR). The results of the measurement of infected samples were compared with the results obtained in the reference (control) samples. The experiment carried out was focused on assessing the presence of calcium oxalate, which is secreted into the surroundings of the mycelium during the active growing of Serpula lacrymans.

2021 ◽  
Vol 7 (5) ◽  
pp. 354
Author(s):  
Julia Embacher ◽  
Sigrid Neuhauser ◽  
Susanne Zeilinger ◽  
Martin Kirchmair

The dry rot fungus Serpula lacrymans causes significant structural damage by decaying construction timber, resulting in costly restoration procedures. Dry rot fungi decompose cellulose and hemicellulose and are often accompanied by a succession of bacteria and other fungi. Bacterial–fungal interactions (BFI) have a considerable impact on all the partners, ranging from antagonistic to beneficial relationships. Using a cultivation-based approach, we show that S. lacrymans has many co-existing, mainly Gram-positive, bacteria and demonstrate differences in the communities associated with distinct fungal parts. Bacteria isolated from the fruiting bodies and mycelia were dominated by Firmicutes, while bacteria isolated from rhizomorphs were dominated by Proteobacteria. Actinobacteria and Bacteroidetes were less abundant. Fluorescence in situ hybridization (FISH) analysis revealed that bacteria were not present biofilm-like, but occurred as independent cells scattered across and within tissues, sometimes also attached to fungal spores. In co-culture, some bacterial isolates caused growth inhibition of S. lacrymans, and vice versa, and some induced fungal pigment production. It was found that 25% of the isolates could degrade pectin, 43% xylan, 17% carboxymethylcellulose, and 66% were able to depolymerize starch. Our results provide first insights for a better understanding of the holobiont S. lacrymans and give hints that bacteria influence the behavior of S. lacrymans in culture.


2020 ◽  
Author(s):  
Mouatamid El Hazzat ◽  
Adnane El Hamidi ◽  
Mohammed Halim ◽  
said ARSALANE

Abstract This study focused on a detailed examination of the thermal behavior of Brushite-based calcium phosphate (CaHPO 4 .2H 2 O, DCPD) to identify and characterize the intermediate phases which have been the subject of previous several controversies. For that, in situ high-temperature X-ray diffraction supported by infrared spectroscopy, thermal analysis, and scanning electron microscopy analysis were used and the results showed that the progressive thermal stress of DCPD in air resulted in a heterogeneous formulation consisting of dibasic calcium phosphate anhydrous (CaHPO 4 , DCPA) and an amorphous phase, which appears at low temperatures (~160 °C) and persists up to 375 °C. The deep examination of the amorphous phase by infrared spectroscopy revealed that its chemical composition is similar to that of disordered calcium pyrophosphate (Ca 2 P 2 O 7 , CPP) with the appearance of a characteristic band δ(P-O-P), located at 740 cm -1 . This IR band is shifted to low frequencies (725 cm -1 ) as the temperature is increased, indicating the crystallization of the amorphous phase into γ-CPP. The high temperature treatment (≥ 375 °C) leads to b-CPP polymorph. According to the present characterization results, obtaining pure DCPA from the thermal dehydration of DCPD is not effective and leads to biphasic materials including an amorphous phase.


2021 ◽  
Vol 11 (6) ◽  
pp. 2021-2025
Author(s):  
Liujin Wei ◽  
Guan Huang ◽  
Yajun Zhang

The combination of time-resolved transient photoluminescence with in-situ Fourier transform infrared spectroscopy has been conducted to investigate the intrinsic phase structure-dependent activity of Bi2O3 catalyst for CO2 reduction.


2014 ◽  
Vol 1000 ◽  
pp. 154-157
Author(s):  
Zuzana Rácová ◽  
Petra Hrochová ◽  
Pavla Ryparová

Dry rot fungus (Serpula lacrymans) is wood-decaying fungus. It grows frequently in our territory and it causes big damages on structures. Remediation of damaged structures is very difficult, sometimes impossible, therefore it is necessary to study preventive protection against dry rot fungus. PVA nanofibred fabrics with synthetic and natural biocidal additives were used for this experiment. Filter papers soaked in dopes with biocidal substances were other materials used for this experiment. Pieces of nanofiber fabrics and pieces of filter papers soaked in dopes were placed to Petri dishes with broth. Small cuts of dry rot fungus were placed around them. This experiment was performed in conditions, which promote the growth of dry rot fungus. Growth of dry rot fungus was studied.


2016 ◽  
Vol 56 (9) ◽  
pp. 1504 ◽  
Author(s):  
J. P. Keim ◽  
H. Charles ◽  
D. Alomar

An important constraint of in situ degradability studies is the need to analyse a high number of samples and often with insufficient amount of residue, especially after the longer incubations of high-quality forages, that impede the study of more than one nutritional component. Near-infrared spectroscopy (NIRS) has been established as a reliable method for predicting composition of many entities, including forages and other animal feedstuffs. The objective of this work was to evaluate the potential of NIRS for predicting the crude protein (CP) and neutral detergent fibre (NDF) concentration in rumen incubation residues of permanent and sown temperate pastures in a vegetative stage. In situ residues (n = 236) from four swards were scanned for their visible-NIR spectra and analysed for CP and NDF. Selected equations developed by partial least-squares multivariate regression presented high coefficients of determination (CP = 0.99, NDF = 0.95) and low standard errors (CP = 4.17 g/kg, NDF = 7.91 g/kg) in cross-validation. These errors compare favourably to the average concentrations of CP and NDF (146.5 and 711.2 g/kg, respectively) and represent a low fraction of their standard deviation (CP = 38.2 g/kg, NDF = 34.4 g/kg). An external validation was not as successful, with R2 of 0.83 and 0.82 and a standard error of prediction of 14.8 and 15.2 g/kg, for CP and NDF, respectively. It is concluded that NIRS has the potential to predict CP and NDF of in situ incubation residues of leafy pastures typical of humid temperate zones, but more robust calibrations should be developed.


2008 ◽  
Vol 45 (9) ◽  
pp. 1061-1082 ◽  
Author(s):  
Ryan C. McKellar ◽  
Alexander P. Wolfe ◽  
Ralf Tappert ◽  
Karlis Muehlenbachs

The Late Cretaceous Grassy Lake and Cedar Lake amber deposits of western Canada are among North America’s most famous amber-producing localities. Although it has been suggested for over a century that Cedar Lake amber from western Manitoba may be a secondary deposit having originated from strata in Alberta, this hypothesis has not been tested explicitly using geochemical fingerprinting coupled to comparative analyses of arthropod faunal content. Although there are many amber-containing horizons associated with Cretaceous coals throughout Alberta, most are thermally mature and brittle, thus lacking the resilience to survive long distance transport while preserving intact biotic inclusions. One of the few exceptions is the amber found in situ at Grassy Lake. We present a suite of new analyses from these and other Late Cretaceous ambers from western Canada, including stable isotopes (H and C), Fourier transform infrared (FTIR) spectra, and an updated faunal compendium for the Grassy and Cedar lakes arthropod assemblages. When combined with amber’s physical properties and stratigraphic constraints, the results of these analyses confirm that Cedar Lake amber is derived directly from the Grassy Lake amber deposit or an immediate correlative equivalent. This enables the palaeoenvironmental context of Grassy Lake amber to be extended to the Cedar Lake deposit, making possible a more inclusive survey of Cretaceous arthropod faunas.


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