Reducing the Environmental Hazard of Spent Cleaning Masses from the Production of Acetylene Carbide

2021 ◽  
Vol 25 (9) ◽  
pp. 8-14
Author(s):  
R.N. Plotnikova ◽  
V.I. Korchagin ◽  
L.V. Popova ◽  
M.V. Maltsev
Keyword(s):  
Hydrogen Sulfide ◽  
Plant Nutrition ◽  
Solid Support ◽  
Absorption Capacity ◽  
Environmental Hazard ◽  
Biogenic Element ◽  
Optimal Conditions ◽  
Secondary Use ◽  
Solid Carrier

Methods of reducing the environmental hazard during storage of spent cleaning masses formed in the production of acetylene by the wet method are considered. The optimal conditions for the process of neutralizing the waste of the cleaning mass accumulating at the stage of trapping phosphine and hydrogen sulfide in the process of obtaining acetylene by the carbide method have been established. Ways of regeneration of a solid carrier included in the composition of cleaning masses are proposed. The possibility of secondary use of the regenerated solid support — expanded pearlite — has been investigated. A scheme for the neutralization of wastes from the production of carbide acetylene is presented. Methods for restoring the absorption capacity of a solid carrier are proposed. The prospect of using partially regenerated waste from the stage of washing soluble compounds containing sparingly soluble phosphates for mulching soils and increasing the influx of an important biogenic element for plant nutrition and growth is shown.

scholarly journals Effective Enhancement of Water Absorbency of Itaconic Acid Based-Superabsorbent Polymer via Tunable Surface—Crosslinking

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2782
Author(s):  
Yong-Rok Kwon ◽  
Jung-Soo Kim ◽  
Dong-Hyun Kim
Keyword(s):  
Itaconic Acid ◽  
Photoelectron Spectroscopy ◽  
Crosslinking Agent ◽  
Absorption Capacity ◽  
Gel Strength ◽  
Superabsorbent Polymer ◽  
Optimal Conditions ◽  
Retention Capacity ◽  
X Ray ◽  
Crosslinking Reactions

A superabsorbent polymer (SAP) was synthesized by copolymerizing itaconic acid and vinyl sulfonic acid. The typically low absorbency of itaconic acid-based SAPs under mechanical loads was improved by introducing surface crosslinking. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the synthesis and surface-crosslinking reactions in the SAP. Various conditions for surface-crosslinking reactions, such as the surface-crosslinking solution, content of surface-crosslinking agent, and reaction temperature, were explored and correlated with the gel strength and absorption characteristics of the resulting SAP particles. The distilled water content in the surface-crosslinking solution strongly influenced the absorption capacity of the SAP, but this sensitivity decreased when acetone was used as a co-solvent. Itaconic acid-based SAP that was crosslinked under optimal conditions exhibited centrifuge retention capacity and absorbency under a load of 31.1 and 20.2, respectively.

scholarly journals Optimal Conditions for Production of Fermented Flour from Pumpkin (Cucurbita pepo L.) for Infant Foods

2019 ◽  
pp. 125-136
Author(s):  
William Dzusuo Tedom ◽  
Edith Nig Fombang ◽  
Wilfred Damndja Ngaha ◽  
Richard Aba Ejoh
Keyword(s):  
Functional Properties ◽  
Mineral Content ◽  
Reducing Sugars ◽  
Absorption Capacity ◽  
Infant Food ◽  
Optimal Conditions ◽  
Food Matrix ◽  
Total Carotenoids ◽  
Lactic Fermentation ◽  
Infant Foods

The aim of this study was to determine the optimal conditions for production of a fermented pumpkin flour by lactic fermentation using Lactobacillus plantarum and the effect of the fermentation on nutritional potential and functional properties of pumpkin. To achieve this, pumpkin fruit was collected in the Ngaoundere main market, peeled, sliced, and the flesh obtained was grated, pasteurized at 90ºC for 5 minutes and placed under lactic fermentation using L. plantarum (108 cfu/mL). The sample obtained was dried at 45ºC ± 2ºC for 24 hours and crushed to obtain a flour with particle size ≤ 500 µm. According to the Doehlert's plan used, time and temperature of fermentation varied from 24 to 96 hours and 30 to 50°C respectively. Responses sought were the optimal levels of total carotenoids and reducing sugars in the flours. Chemical composition of flour was determined to evaluate the effect of fermentation on food matrix used. Results indicate that to produce a pumpkin flour with highest content in both carotenoids and reducing sugars, optimal conditions of lactic fermentation with L. plantarum are 70h at 45°C. Under these conditions, there is a decrease of 72.1% of proteins and 67% of fibers, against an increase of 106% of reducing sugars. Total carotenoids content decreased by 4.6%, but the level is still higher than the threshold recommended for infant food formulation, while mineral content increases with fermentation. A reduction of anti-nutrients (phytates, tannins, phenolic compounds and oxalates) of more than 50% is also observed when fermenting pumpkin. The functional properties of fermented pulp show a decrease of water absorption capacity of 24% and an increase of 134.4% in bulk density. Fermented pumpkin flour could be used in infant food formulation, but need to be associated with other sources of proteins and minerals.

Production of Gallic Acid by Immobilized Aspergillus niger Using Polyurethane Foam as Solid Support

2011 ◽  
Vol 7 (6) ◽  
Author(s):  
Anita Srivastava ◽  
Rita Kar
Keyword(s):  
Aspergillus Niger ◽  
Gallic Acid ◽  
Polyurethane Foam ◽  
Acid Production ◽  
Immobilized Cells ◽  
Continuous Production ◽  
Solid Support ◽  
Simultaneous Increase ◽  
Acid Decarboxylase ◽  
Optimal Conditions

The present study was aimed at finding the optimal conditions for maximum gallic acid production using polyurethane-immobilized Aspergillus niger cells and determining the operational stability of recycled cells for gallic acid production. Maximum gallic acid (142 µg/ml) was produced with 1% tannic acid at 40°C, pH 5.0, with polyurethane foam size of 1.5 cm3 cubes after 48 h under submerged fermentation at 220 rpm, as compared to free cells, which produced 72 µg /ml gallic acid in 72 h at 37°C and pH 5.0. Continuous production of gallic acid by recycling of the immobilized cells resulted in maximum gallic acid production of 199 µg/ml after the fourth cycle, and thereafter remained stable till the seventh cycle and could be continued till the tenth cycle. Pyrogallol, a degradation product of gallic acid and gallic acid decarboxylase (GADC), was also monitored under static and aerobic states and showed comparable values, in contrast to bacteria where aeration caused inhibition. However, 72.73% inhibition of GADC activity by oxidizing agents with simultaneous increase in gallic acid production was observed. This is the first report of gallic acid production by immobilized A. niger cells, producing higher amounts of gallic acid in a shorter cultivation time.

Amorphous silica coating on α-alumina particles

1995 ◽  
Vol 53 ◽  
pp. 210-211
Author(s):  
J. W. Mellowes ◽  
C. M. Chun ◽  
I. A. Aksay
Keyword(s):  
Amorphous Silica ◽  
Heterogeneous Nucleation ◽  
Homogeneous Nucleation ◽  
Silica Coating ◽  
Full Density ◽  
Optimal Conditions ◽  
Fine Grained ◽  
Alumina Particles ◽  
Complete Mullitization ◽  
Powder Compacts

Mullite (3Al2O32SiO2) can be fabricated by transient viscous sintering using composite particles which consist of inner cores of a-alumina and outer coatings of amorphous silica. Powder compacts prepared with these particles are sintered to almost full density at relatively low temperatures (~1300°C) and converted to dense, fine-grained mullite at higher temperatures (>1500°C) by reaction between the alumina core and the silica coating. In order to achieve complete mullitization, optimal conditions for coating alumina particles with amorphous silica must be achieved. Formation of amorphous silica can occur in solution (homogeneous nucleation) or on the surface of alumina (heterogeneous nucleation) depending on the degree of supersaturation of the solvent in which the particles are immersed. Successful coating of silica on alumina occurs when heterogeneous nucleation is promoted and homogeneous nucleation is suppressed. Therefore, one key to successful coating is an understanding of the factors such as pH and concentration that control silica nucleation in aqueous solutions. In the current work, we use TEM to determine the optimal conditions of this processing.

Immunocytochemical methodology for the localization of neuronal antigens at the ultrastructural level

1990 ◽  
Vol 48 (3) ◽  
pp. 876-877
Author(s):  
Jorge Pecci Saavedra ◽  
Mark Connaughton ◽  
Juan José López ◽  
Alicia Brusco
Keyword(s):  
Spinal Cord ◽  
Substantia Nigra ◽  
Polyclonal Antibodies ◽  
Ultrastructural Level ◽  
Point Of View ◽  
Nerve Tissue ◽  
Tissue Fixation ◽  
Optimal Conditions ◽  
Interpeduncular Nucleus ◽  
Technical Point

The use of antibodies as labels for the localization of specific molecules in the nervous systan has been extensively applied in recent years. Both monoand polyclonal antibodies or antisera have been employed. The knowledge of the organization of neuronal connectivities, gliovascular relationships, glioneuronal relationships and other features of nerve tissue has greatly increased.A number of areas of the nervous systan have been analyzed in our laboratory, including the nuclei of the raphe system, the reticular formation, interpeduncular nucleus, substantia nigra, caudate nucleus, putamen, pallidum, spinal cord, pineal gland and others.From a technical point of view, a number of variables needed to be taken into account in order to obtain reliable and reproducible results. The design of the optimal conditions of tissue fixation, embedding, sectioning, dilution of antibodies, and adaptation of Sternberger PAP technique were sane of the parameters taken into account to optimize the results. It is critical that each step of the technique be defined for each particular case.

Endogenous hydrogen sulfide sulfhydrates IKKβ at cysteine 179 to control pulmonary artery endothelial cell inflammation

2019 ◽  
Vol 133 (20) ◽  
pp. 2045-2059 ◽  
Author(s):  
Da Zhang ◽  
Xiuli Wang ◽  
Siyao Chen ◽  
Selena Chen ◽  
Wen Yu ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Endothelial Cell ◽  
Pulmonary Artery ◽  
Cell Model ◽  
Site Directed Mutagenesis ◽  
Critical Event ◽  
Hypertensive Rats ◽  
Pulmonary Artery Endothelial Cell

Abstract Background: Pulmonary artery endothelial cell (PAEC) inflammation is a critical event in the development of pulmonary arterial hypertension (PAH). However, the pathogenesis of PAEC inflammation remains unclear. Methods: Purified recombinant human inhibitor of κB kinase subunit β (IKKβ) protein, human PAECs and monocrotaline-induced pulmonary hypertensive rats were employed in the study. Site-directed mutagenesis, gene knockdown or overexpression were conducted to manipulate the expression or activity of a target protein. Results: We showed that hydrogen sulfide (H2S) inhibited IKKβ activation in the cell model of human PAEC inflammation induced by monocrotaline pyrrole-stimulation or knockdown of cystathionine γ-lyase (CSE), an H2S generating enzyme. Mechanistically, H2S was proved to inhibit IKKβ activity directly via sulfhydrating IKKβ at cysteinyl residue 179 (C179) in purified recombinant IKKβ protein in vitro, whereas thiol reductant dithiothreitol (DTT) reversed H2S-induced IKKβ inactivation. Furthermore, to demonstrate the significance of IKKβ sulfhydration by H2S in the development of PAEC inflammation, we mutated C179 to serine (C179S) in IKKβ. In purified IKKβ protein, C179S mutation of IKKβ abolished H2S-induced IKKβ sulfhydration and the subsequent IKKβ inactivation. In human PAECs, C179S mutation of IKKβ blocked H2S-inhibited IKKβ activation and PAEC inflammatory response. In pulmonary hypertensive rats, C179S mutation of IKKβ abolished the inhibitory effect of H2S on IKKβ activation and pulmonary vascular inflammation and remodeling. Conclusion: Collectively, our in vivo and in vitro findings demonstrated, for the first time, that endogenous H2S directly inactivated IKKβ via sulfhydrating IKKβ at Cys179 to inhibit nuclear factor-κB (NF-κB) pathway activation and thereby control PAEC inflammation in PAH.

Stability of antioxidant vitamins in whole human blood during overnight storage at 4°C and frozen storage up to 6 months

2018 ◽  
Vol 88 (3-4) ◽  
pp. 151-157 ◽  
Author(s):  
Scott W. Leonard ◽  
Gerd Bobe ◽  
Maret G. Traber
Keyword(s):  
Ascorbic Acid ◽  
Whole Blood ◽  
Healthy Subjects ◽  
Frozen Storage ◽  
Blood Collection ◽  
Plasma Samples ◽  
Optimal Conditions ◽  
Plasma Ascorbic Acid ◽  
Blood Samples ◽  
Sample Handling

Abstract. To determine optimal conditions for blood collection during clinical trials, where sample handling logistics might preclude prompt separation of erythrocytes from plasma, healthy subjects (n=8, 6 M/2F) were recruited and non-fasting blood samples were collected into tubes containing different anticoagulants (ethylenediaminetetra-acetic acid (EDTA), Li-heparin or Na-heparin). We hypothesized that heparin, but not EDTA, would effectively protect plasma tocopherols, ascorbic acid, and vitamin E catabolites (α- and γ-CEHC) from oxidative damage. To test this hypothesis, one set of tubes was processed immediately and plasma samples were stored at −80°C, while the other set was stored at 4°C and processed the following morning (~30 hours) and analyzed, or the samples were analyzed after 6 months of storage. Plasma ascorbic acid, as measured using HPLC with electrochemical detection (LC-ECD) decreased by 75% with overnight storage using EDTA as an anticoagulant, but was unchanged when heparin was used. Neither time prior to processing, nor anticoagulant, had any significant effects upon plasma α- or γ-tocopherols or α- or γ-CEHC concentrations. α- and γ-tocopherol concentrations remained unchanged after 6 months of storage at −80°C, when measured using either LC-ECD or LC/mass spectrometry. Thus, refrigeration of whole blood at 4°C overnight does not change plasma α- or γ-tocopherol concentrations or their catabolites. Ascorbic acid is unstable in whole blood when EDTA is used as an anticoagulant, but when whole blood is collected with heparin, it can be stored overnight and subsequently processed.

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