scholarly journals Analysis of the Pyrolytic Behaviour of Birch, Maple, and Rowan Leaves

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2091
Author(s):  
Valentina Zubkova ◽  
Andrzej Strojwas ◽  
Marcin Bielecki

A research study was conducted on the thermal behaviour of leaves of urban greenery (birch, maple, and rowan) and the products of their pyrolysis and extraction as assisted by microwaves. The obtained products of pyrolysis and extraction were investigated with the use of FT-IR and UV spectroscopies and XRD techniques. A contractive analysis of samples of chars, condensates, after-extraction residue, and extracts showed that the changes in structural-chemical parameters of leaves of different types of trees during pyrolysis and extraction take place in distinct ways. About 22% of material was removed from birch leaves during extraction, and more than 17% of material was extracted from maple and rowan leaves. It was determined that, during pyrolysis of after-extraction residue of leaves, many fewer PAH compounds with carbonyl groups along with alcohols and phenols are emitted than during pyrolysis of non-extracted leaves. Taking into account that pyrolysis is the first stage of combustion, a decrease in the amount of dangerous compounds in the volatile products of pyrolysis leads to a lower contribution of such compounds in combustion products. This indicates that leaves of urban greenery can be subjected to combustion after extraction, and the obtained extracts can be used as a source of phytochemicals and chemical reagents.

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 239
Author(s):  
Wei Wang ◽  
Long Liang ◽  
Yaoli Peng ◽  
Maria Holuszko

Micro-Fourier transform infrared (micro-FTIR) spectroscopy was used to correlate the surface chemistry of low rank coal with hydrophobicity. Six square areas without mineral impurities on low rank coal surfaces were selected as testing areas. A specially-designed methodology was applied to conduct micro-FTIR measurements and contact angle tests on the same testing area. A series of semi-quantitative functional group ratios derived from micro-FTIR spectra were correlated with contact angles, and the determination coefficients of linear regression were calculated and compared in order to identify the structure of the functional group ratios. Finally, two semi-quantitative ratios composed of aliphatic carbon hydrogen, aromatic carbon hydrogen and two different types of carbonyl groups were proposed as indicators of low rank coal hydrophobicity. This work provided a rapid way to predict low rank coal hydrophobicity through its functional group composition and helped us understand the hydrophobicity heterogeneity of low rank coal from the perspective of its surface chemistry.


2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.


2021 ◽  
Vol 900 (1) ◽  
pp. 012036
Author(s):  
P Polko ◽  
K Kimic

Abstract Personal security is one of the key aspects affected by the perception of urban greenery, which plays an important role for city dwellers. The survey conducted in Poland in 2020 (N=394) aimed to check how important for park users in context of perceived security are selected factors related to maintenance of different types of park infrastructure (condition of equipment and pavement, also condition of greenery), level of park cleanliness (filling of the rubbish bins, litter on the ground, and graffiti on different types of facilities), and elements related to the use of park space (paths, varied topography, functional aids, and water). The condition of equipment was assessed as a factor of high impact (average of 4.13 in 5-point Likert scale), as well as the presence of park paths (4.02). The results indicate that all 10 of the examined factors are recognized as important (3 and higher). They also show that both women (compared to men) and older respondents (compared to those under 60) assessed higher the importance of factors related to the condition of elements of infrastructure and pavement, as well as the level of cleanliness in urban parks in shaping their personal sense of security.


Author(s):  
Guilherme Botega Torsoni ◽  
Cícero Rafael Cena ◽  
Gustavo Quereza de Freitas ◽  
Claudio Luis Carvalho

In this paper, we present a detailed route of synthesis to produce ceramic superconductor Bi1,6Pb0,4Sr2Ca2Cu3Ox (Bi,Pb)-2223 powder by Pechini method. The obtained polymeric precursor solution was produced by using inexpensive chemical reagents, which showed a great stability for three weeks with high concentration of BPSCCO inorganic ions. The crystallization kinetic of BPSCCO powder was investigated by thermal analysis (DSC/TGA) and X-ray diffraction (XRD) techniques. The thermal treatment of the BPSCCO powder at different temperatures showed that complex phase equilibrium occurs to the system. The three superconductor phases seems to coexist in a large range of temperature, the Bi-2201 phase was crystallized around 500 oC and then, after 840 oC the desirable (Bi,Pb)-2223 phase appears with coexistence of the Bi-2212 phase at low quantity. Finally, the powder morphology was characterized by scanning electron microscopy (SEM), the results point to a typical plate like formation of the grains.


Author(s):  
Ying Chen ◽  
Jinfang Huang ◽  
Zhao Qin Yeap ◽  
Xue Zhang ◽  
Shuisheng Wu ◽  
...  

Crystals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 267 ◽  
Author(s):  
Reza Kia ◽  
Azadeh Kalaghchi

The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene, 2,4-Me2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene, 2,4-Me2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene, 2,4,6-Me3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene, 2,6-ipr2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR, 1H-NMR, 13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each complex, the Re(I) centre shows a distorted octahedral shape with a facial geometry of carbonyl groups. The gas phase geometry of the complexes was identified by density functional theory. Interesting intermolecular n…π* interactions of complexes 1 and 3 were investigated by non-covalent interaction index (NCI), and natural bond orbital (NBO) analyses. The intramolecular n…σ*, σ…π*, π…σ* interactions were also studied in complexes 3 and 4.


Cellulose ◽  
2020 ◽  
Vol 27 (15) ◽  
pp. 8977-8987
Author(s):  
Floriana Coppola ◽  
Alberto Modelli

Abstract The degradation of paper-based materials involves several and complex mechanisms, such as hydrolysis and oxidation. The behaviour of different types of pulps can be very variable. In this study, the difference upon oxidation of contemporary non-recycled and recycled papers, which now constitute a considerable fibre source, is investigated. A 0.015 M potassium periodate solution is used to oxidise five types of paper, two non-recycled and three recycled, for 0.5, 1, 2 and 4 h. The effects of such oxidation treatments are evaluated in terms of carbonyl content and degree of polymerisation (DP). A modified procedure of the Szabolcs’s method and viscometry are used to measure the carbonyl content and DP, respectively. The carbonyl groups are found to increase more rapidly in the recycled papers than in the non-recycled ones. On the contrary, oxidation causes a larger decrease of the DP values in the non-recycled papers, the paper made of pure cellulose being the most sensitive in terms of depolymerisation. The DP values measured for pure cellulose paper are in line with previously reported data. Moreover, in accordance with the Ekenstam equation, the plots of the reciprocal of DP as a function of oxidation time show good linear correlations for all types of paper investigated. Pseudo rate constants are thus calculated from the slopes of these plots, those of the non-recycled papers being found to be higher than those of the recycled papers. Graphic abstract


2019 ◽  
Vol 74 (2) ◽  
pp. 178-186 ◽  
Author(s):  
Abigail V. Rutter ◽  
Jamie Crees ◽  
Helen Wright ◽  
Marko Raseta ◽  
Daniel G. van Pittius ◽  
...  

The rising incidence of cancer worldwide is causing an increase in the workload in pathology departments. This, coupled with advanced analysis methodologies, supports a developing need for techniques that could identify the presence of cancer cells in cytology and tissue samples in an objective, fast, and automated way. Fourier transform infrared (FT-IR) microspectroscopy can identify cancer cells in such samples objectively. Thus, it has the potential to become another tool to help pathologists in their daily work. However, one of the main drawbacks is the use of glass substrates by pathologists. Glass absorbs IR radiation, removing important mid-IR spectral data in the fingerprint region (1800 cm−1 to 900 cm−1). In this work, we hypothesized that, using glass coverslips of differing compositions, some regions within the fingerprint area could still be analyzed. We studied three different types of cells (peripheral blood mononuclear cells, a leukemia cell line, and a lung cancer cell line) and lymph node tissue placed on four different types of glass coverslips. The data presented here show that depending of the type of glass substrate used, information within the fingerprint region down to 1350 cm−1 can be obtained. Furthermore, using principal component analysis, separation between the different cell lines was possible using both the lipid region and the fingerprint region between 1800 cm−1 and 1350 cm−1. This work represents a further step towards the application of FT-IR microspectroscopy in histopathology departments.


1977 ◽  
Vol 55 (10) ◽  
pp. 1345-1350 ◽  
Author(s):  
Isabel F. Alvarez ◽  
Fields W. Cobb Jr.

Nine different types of mycorrhizae were observed on naturally occurring white fir seedlings in the north central Sierra Nevada, including one formed by the ubiquitous Cenococcum graniforme. The macro- and micro-scopic characteristics and reactions to different chemical reagents are described for five types. Possible mycorrhizal fungi of white fir are listed. Nursery-grown seedlings examined were ectomycorrhizal; intracellular penetration was not observed. None of the naturally occurring mycorrhizal types were found on nursery seedlings.


1991 ◽  
Vol 69 (11) ◽  
pp. 1639-1642 ◽  
Author(s):  
Michael Jackson ◽  
Henry H. Mantsch

The frequency of the so-called "amide I" band (amide C=O stretching vibration, vC=O) of proteins is discussed in terms of the dihedral angles of the various secondary structures present within proteins. We propose that in the case of intra- or intermolecular hydrogen-bonded amide carbonyl groups the frequency of this absorption can be directly related to the [Formula: see text], ψ angles of the amide moieties for the major secondary structures. Amide I bands at frequencies above those found for non-hydrogen bonded amide carbonyl groups are rationalized in terms of a change in the third dihedral angle, ω. Rotation around the amide C—N bond in sterically demanding structures, such as turns where ω deviates from 180°, is expected to cause an increase in the electron density of the amide carbonyl groups and so increase vC=O to frequencies greater than that seen for unperturbed carbonyl groups. Key words: FT-IR spectroscopy, proteins, structure, dihedral angles.


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