chemical compositions
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2022 ◽  
Vol 4 (1) ◽  
pp. 1-10
Panigrahi M.K ◽  

The aim of the work is to use industrial waste as resource materials for formulating useful product for society. Materials are prepared using Fly ash as main ingredient through sintered process via solid state route. Different materials are prepared using various sintering temperature. The crystal structural and phases are explored by XRD analysis. Mulite phase are investigated, which is indicated the insulating properties of the materials. Surface topography of the prepared materials is analyzed by FESEM characterization. EDS analysis is also done during the FESEM characterization and is assessed the various chemical compositions. Identification of different chemical groups in the processed Fly Ash is carried out by FTIR analysis. Highest electrical resistivity is estimated and is found to be 35.1 MΩ, which indicates the very good insulating property.

2022 ◽  
Junjun Deng ◽  
Hao Ma ◽  
Xinfeng Wang ◽  
Shujun Zhong ◽  
Zhimin Zhang ◽  

Abstract. Brown carbon (BrC) aerosols exert vital impacts on climate change and atmospheric photochemistry due to their light absorption in the wavelength range from near-ultraviolet (UV) to visible light. However, the optical properties and formation mechanisms of ambient BrC remain poorly understood, limiting the estimation of their radiative forcing. In the present study, fine aerosols (PM2.5) were collected during 2016–2017 on a day/night basis over urban Tianjin, a megacity in North China, to obtain seasonal and diurnal patterns of atmospheric water-soluble BrC. There were obvious seasonal but no evident diurnal variations in light absorption properties of BrC. In winter, BrC showed much stronger light absorbing ability since mass absorption efficiency at 365 nm (MAE365) (1.54 ± 0.33 m2 g−1), which was 1.8 times larger than that (0.84 ± 0.22 m2 g−1) in summer. Direct radiative effects by BrC absorption relative to black carbon in the UV range were 54.3 ± 16.9 % and 44.6 ± 13.9 %, respectively. In addition, five fluorescent components in BrC, including three humic-like fluorophores and two protein-like fluorophores were identified with excitation-emission matrix fluorescence spectrometry and parallel factor (PARAFAC) analysis. The lowly-oxygenated components contributed more to winter and nighttime samples, while more-oxygenated components increased in summer and daytime samples. The higher humification index (HIX) together with lower biological index (BIX) and fluorescence index (FI) suggest that the chemical compositions of BrC were associated with a high aromaticity degree in summer and daytime due to photobleaching. Fluorescent properties indicate that wintertime BrC were predominantly affected by primary emissions and fresh secondary organic aerosol (SOA), while summer ones were more influenced by aging processes. Results of source apportionments using organic molecular compositions of the same set of aerosols reveal that fossil fuel combustion and aging processes, primary bioaerosol emission, biomass burning, and biogenic and anthropogenic SOA formation were the main sources of BrC. Biomass burning contributed much larger to BrC in winter and at nighttime, while biogenic SOA contributed more in summer and at daytime. Especially, our study highlights that primary bioaerosol emission is an important source of BrC in urban Tianjin in summer.

Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 542
Yiliang Cheng ◽  
Jennifer Rae Savits ◽  
Aude Annie Watrelot

Cold-hardy interspecific hybrid grape varieties (Vitis spp.) have distinctive chemical compositions such as high acidity, a high content of anthocyanin diglucoside and a low condensed tannins content, compared to Vitis vinifera varieties. Considering the importance of phenolic compounds on the quality of red wine, a mechanical maceration technique, accentuated cut edges (ACE), has been evaluated when applied directly to crushed grapes (ACE-C), and 24 h before pressing (ACE-P), to improve the extraction of phenolic compounds. Samples were collected at crushing, bottling, and after five months of aging. Phenolic compounds and color characteristics of the wines were analyzed by high-performance liquid chromatography (HPLC) with diode array and fluorescence detectors and UV-Visible spectrophotometry. The color intensity, non-anthocyanin monomeric compounds and total iron-reactive phenolics content increased after applying ACE, compared to the control (CTL) after aging, and was significantly higher (37%) after ACE-C, compared to ACE-P. However, the concentration of condensed tannins was below the limit of detection in all the samples, indicating that ACE did not help their extraction or further interactions occurred with disrupted cell wall material. Applying ACE at crushing was considered as the optimum time to achieve a higher color stability in Marquette red wines.

2022 ◽  
Vol 19 (2) ◽  
pp. 2016
Burapha Phajuy ◽  
Vimoltip Singtuen

One of the oldest lime manufactures in Chiang Mai Province is located in a hillside village, Ban Pong, Hang Dong District, the western part of Chiang Mai City. Villagers still have conserved traditional production methods using wood-fired kilns and the primary material selection, an Ordovician marble. There are 2 massive amounts of carbonate rocks distributed in Chiang Mai Province; Permian limestone and Ordovician marble. However, the Ordovician carbonate rocks in Ban Pong were selected to produce high-quality lime by their primitive method (man-made) for a long time. Petrographical studies suggest that the Ordovician rock samples show a granoblastic texture with a slightly foliation represents by mica flakes. They are made up mainly of calcite, with very small amounts of quartz, muscovite, talc, and opaque minerals that can be identified as marble. The mineral compositions are according to the value of CaO, SiO2, Al2O3, K2O, and Fe2O3 in whole-rock analysis by XRF. The geochemical data suggest that marble in the Ban Pong area has a high CaO ratio and contains small amounts of muscovite, quartz, talc, and opaque minerals that may reduce the decomposition temperature during the calcination process. The Ordovician marble in Ban Pong is an appropriate raw material for traditional lime manufacture to saving energy in the production system. HIGHLIGHTS Limestone has been a geologic material in the lime industry from the past to the presence of human society Villagers in Ban Pong (Chiang Mai Province, Thailand) selected the western Ordovician limestone mountains to produce lime by a primitive process instead of the eastern Permian limestone mountains The mineral- and chemical compositions of the Ordovician limestones were intensively analyzed to characterize the suitable raw materials for a primitive lime kiln The mineral composition indicated that the Ordovician limestone in this area is metamorphosed into an impure fine-grained marble GRAPHICAL ABSTRACT

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 578
Agata Lisińska-Czekaj ◽  
Dionizy Czekaj

In the present paper, results of X-ray photoelectron studies of electroceramic thin films of barium strontium titanate, Ba1−xSrxTiO3 (BST), composition deposited on stainless-steel substrates are presented. The thin films were prepared by the sol-gel method. A spin-coating deposition of BST layers with different chemical compositions was utilized so the layer-type structure of (0-2) connectivity was formed. After the deposition, the thin-film samples were heated in air atmosphere at temperature T = 700 °C for 1 h. The surfaces of BST thin films subjected to thermal treatment were studied by X-ray diffraction. X-ray diffraction measurements confirmed the perovskite-type phase for all grown thin-film samples. The oxidation states of the elements were examined by the X-ray photoelectron spectroscopy method. X-ray photoelectron spectroscopy survey spectra as well as high-resolution spectra (photo-peaks) of the main metallic elements, such as Ti, Ba, and Sr, were compared for the layer-type structures, differing in the deposition sequence of the barium strontium titanate layers constituting the BST thin film.

Eos ◽  
2022 ◽  
Vol 103 ◽  
JoAnna Wendel

Researchers applied machine learning algorithms to several distinct chemical compositions of Mars and suggest that these algorithms could be a powerful tool to map the planet’s surface on a large scale.

Li Xiao ◽  
Yingqiang Xu ◽  
Zhiyong Chen

Abstract To improve the fretting wear performance of 18CrNi4A steel, DLC, TiAlN and DLC/TiAlN coatings were deposited on the surface of carburized 18CrNi4A steel, respectively. The microstructure morphologies, chemical compositions, and mechanical properties of these coatings were evaluated. The fretting tribological properties of pad/flat contact pairs for carburized 18CrNi4A steel, DLC, TiAlN and DLC/TiAlN coatings were investigated in different lubricant environments including dry sliding and #RIPP 7254 aviation grease. The results show that DLC, TiAlN and DLC/TiAlN coatings deposited on the carburized 18CrNi4A steel surface can improve surface roughness, hardness, fracture toughness and resistance to plastic deformation. DLC, TiAlN and DLC/TiAlN coatings deposited on the surface of carburized 18CrNi4A steel can make the surface of the substrate have excellent fretting wear properties. DLC and DLC/TiAlN coatings have lower coefficient of friction and better fretting wear resistance than TiAlN coatings in dry sliding condition, and DLC/TiAlN coatings have the lowest wear rate in #RIPP 7254 grease lubrication condition. In addition, the wear mechanisms of carburized 18CrNi4A steel, DLC, TiAlN and DLC/TiAlN coatings in dry sliding and #RIPP 7254 aviation grease conditions were analyzed.

2022 ◽  
Vol 12 (1) ◽  
Panita Chutimanukul ◽  
Praderm Wanichananan ◽  
Supattana Janta ◽  
Theerayut Toojinda ◽  
Clive Terence Darwell ◽  

AbstractLight-emitting diodes (LEDs) are an artificial light source used in indoor cultivation to influence plant growth, photosynthesis performance and secondary metabolite synthesis. Holy basil plants (Ocimum tenuiflorum) were cultivated under fully controlled environmental conditions with different red (R) and blue (B) light intensity ratios (3R:1B, 1R:1B and 1R:3B), along with combined green (G) LED (2R:1G:2B). The photosynthetic activities of both cultivars were maximal under 3R:1B. However, the highest fresh (FW) and dry (DW) weight values of green holy basil were recorded under 3R:1B and 2R:1G:2B, significantly higher than those under alternative light conditions. For red holy basil, the highest FW and DW were recorded under 1R:3B. Moreover, 2R:1G:2B treatment promoted pigment (chlorophyll and carotenoid) accumulation in green holy basil, while red holy basil was found to be rich in both pigments under 3R:1B. Antioxidant capacity was also influenced by light spectrum, resulting in greater total phenolic content (TPC) and DPPH accumulation in both cultivars under 1R:3B. The highest content of flavonoid in green holy basil was detected under 1R:1B; meanwhile, 1R:3B treatment significantly promoted flavonoid content in red holy basil. In addition, anthocyanin content increased in red holy basil under 1R:3B conditions. Gas chromatography coupled with mass spectrometry (GC–MS/MS) analysis of chemical composition showed higher proportional accumulation in Methyleugenol and Caryophyllene of two cultivars grown under all light spectrum ratios at two developmental stages. Overall, specific light spectrum ratios induced different chemical composition responses in each cultivar and at each developmental stage. These results suggest that 3R:1B was favorable for biomass accumulation and photosynthetic responses in green holy basil, while 1R:3B provided antioxidant accumulation. For red holy basil cultivation, 1R:3B provided optimal growing conditions, promoting improvements in plant biomass, and physiological and antioxidant capacities.

2022 ◽  
Vol 9 ◽  
Hung-Chun Chao ◽  
Chen-Feng You ◽  
In-Tian Lin ◽  
Hou-Chun Liu ◽  
Ling-Ho Chung ◽  

Mud volcano is one of the most important conduits for deep seated materials to migrate upward in sedimentary basins, convergent margins, and subduction zones. Understanding their temporal and spatial characteristics and variations provides us the important information on fluid sources and chemical compositions at depth. Mud volcano Lei-Gong-Huo (MV LGH) is a unique mud volcano, which is located on the mélange formation lying on the andesitic volcanic arc. Fluids emitted from 46 mud pools in MV LGH in eastern Taiwan were sampled and their major trace constitutes as well as H, O, and Sr isotopes (87Sr/86Sr and δ88Sr) were measured. Major constitutes of the fluids are Cl−, Na, and Ca. Compared with seawater, LGH fluids have lower Cl−, δD, δ18O, Na/Cl, K/Cl, and Mg/Cl but higher Ca/Cl ratios, indicating water–rock interaction of igneous rock and the ancient seawater at the source region. This interpretation is further supported by Sr isotopes, which show low value of 87Sr/86Sr ratio down to 0.70708. The result of spatial distribution showing strong negative correlation between Na and Ca concentration as well as Ca and 87Sr/86Sr ratios indicates that two end-member mixing is the major chemical characteristic. The fluids interacting with igneous rock carry high Ca, high δ88Sr, low Na, and low 87Sr/86Sr ratio, while those interacting with sedimentary rock carry low Ca, low δ88Sr, high Na, and high 87Sr/86Sr ratio. The source from the igneous region dominates the eastern and southeastern parts of the mud pools while sedimentary source dominates the western and northwestern parts. Most mud pools show mixing behavior between the two sources. Some of the sedimentary-dominated mud pools reveal existence of residual ancient water as indicated by 87Sr/86Sr. The major factor to fractionate the stable Sr isotopes in LGH waters is the source lithology. In summary, fluids emitted by mud pools in LGH originate from two sources, which are water–rock interactions of igneous rock with the ancient seawater from the east and sedimentary rock from the west at depth, resulting from the complex geologic background of mélange formation.

Minerals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 79
Masanori Kurosawa ◽  
Masao Semmoto ◽  
Toru Shibata

Several pottery sherds from the Svilengrad-Brantiite site, Bulgaria, were mineralogically and petrographically analyzed. The aim was to add information to the very scarce material data available for Early Bronze Age pottery in the southeastern Thrace plain, Bulgaria, in order to examine a possible raw-material source of the pottery. The characterization techniques applied were optical microscopy (OM), petrographic microscopy (PM), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS), X-ray fluorescence (XRF) spectroscopy, and X-ray diffraction (XRD). The pottery samples consisted of two typological groups: a local-made type and a cord-impressed decoration type influenced by foreign cultures. All of the samples were produced from fine clay pastes that had a quite similar composition, with abundant mineral grains of similar mineral composition and fragments of metamorphic and granitic rocks. The chemical compositions of each mineral in the grains and fragments were almost identical, and consistent with those from metamorphic and granitic rocks from the Sakar-Strandja Mountains near the study site. The clay paste compositions corresponded to those of illite/smectite mixed-layer clay minerals or mixtures of illite and smectite, and the clay-mineral species were consistent with those in Miocene–Pleistocene or Holocene sediments surrounding the site.

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