Zwitterionic sulfamic acid functionalized nanoclay: A novel nanocatalyst for the synthesis of dihydropyrano[2,3-c]pyrazoles and spiro[indoline-3,4 ´ -pyrano[2,3-c]pyrazole] derivatives

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

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EVALUATION OF ANTI-INFLAMMATORY AND ANALGESIC ACTIVITY OF NOVEL PYRAZOLE DERIVATIVES

Asian Journal of Biomedical and Pharmaceutical Sciences ◽

10.15272/ajbps.v4i37.594 ◽

2014 ◽

Vol 4 (37) ◽

pp. 21-24 ◽

Cited By ~ 3

Author(s):

Abhay Kumar Verma

Keyword(s):

Analgesic Activity ◽

Pyrazole Derivatives ◽

Anti Inflammatory

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A technique for uranium and plutonium determination using coulometric potentiostatic facility UPK-19 for analysis of mixed-oxide fuel

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-12-15-22 ◽

2020 ◽

Vol 86 (12) ◽

pp. 15-22

Author(s):

N. A. Bulayev ◽

E. V. Chukhlantseva ◽

O. V. Starovoytova ◽

A. A. Tarasenko

Keyword(s):

Acid Solution ◽

Mass Fraction ◽

Background Electrolyte ◽

Stable State ◽

Sulfamic Acid ◽

Oxide Fuel ◽

Oxidation Current ◽

Mox Fuel ◽

Mass Fractions ◽

Uranium Plutonium

The content of uranium and plutonium is the main characteristic of mixed uranium-plutonium oxide fuel, which is strictly controlled and has a very narrow range of the permissible values. We focused on developing a technique for measuring mass fractions of uranium and plutonium by controlled potential coulometry using a coulometric unit UPK-19 in set with a R-40Kh potentiostat-galvanostat. Under conditions of sealed enclosures, a special design of the support stand which minimized the effect of fluctuations in ambient conditions on the signal stability was developed. Optimal conditions for coulometric determination of plutonium and uranium mass fractions were specified. The sulfuric acid solution with a molar concentration of 0.5 mol/dm3 was used as a medium. Lead ions were introduced into the background electrolyte to decrease the minimum voltage of hydrogen reduction to –190 mV. The addition of aluminum nitride reduced the effect of fluoride ions participating as a catalyst in dissolving MOX fuel samples, and the interfering effect of nitrite ions was eliminated by introducing a sulfamic acid solution into the cell. The total content of uranium and plutonium was determined by evaluation of the amount of electricity consumed at the stage of uranium and plutonium co-oxidation. Plutonium content was measured at the potentials, at which uranium remains in the stable state, which makes it possible to subtract the contribution of plutonium oxidation current from the total oxidation current. The error characteristics of the developed measurement technique were evaluated using the standard sample method and the real MOX fuel pellets. The error limits match the requirements set out in the specifications for MOX fuel. The technique for measuring mass fractions of uranium and plutonium in uranium-plutonium oxide nuclear fuel was certified. The relative measurement error of the mass fraction of plutonium and uranium was ±0.0070 and ±0.0095, respectively. The relative error of the ratio of the plutonium mass fraction to the sum of mass fractions of uranium and plutonium was ±0.0085.

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Synthesis and biological evaluation of Schiff bases and pyrazole derivatives derive from chalcones, (2E)1-(4-aminophenyl)-3-(2-furyl)prop-2-en-1-one

International Journal of Pharmaceutical Research ◽

10.31838/ijpr/2020.12.01.138 ◽

2020 ◽

Vol 12 (1) ◽

Keyword(s):

Schiff Bases ◽

Biological Evaluation ◽

Pyrazole Derivatives ◽

Synthesis And Biological Evaluation

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Microwave assisted synthesis of novel Pyrazole derivatives and their biological evaluation as anti-bacterial agents

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666201019152206 ◽

2020 ◽

Vol 23 ◽

Author(s):

Hadis Khodadad ◽

Farhad Hatamjafari ◽

Khalil Pourshamsian ◽

Babak Sadeghi

Keyword(s):

Antibacterial Activity ◽

Aromatic Aldehydes ◽

Catalytic Amount ◽

Antibacterial Activities ◽

Structural Features ◽

Biological Evaluation ◽

Aureus Strain ◽

Microwave Assisted Synthesis ◽

Pyrazole Derivatives ◽

Microwave Assisted

Aim and Objective: Microwave-assisted condensation of acetophenone 1 and aromatic aldehydes 2 gave chalcone analogs 3, which were cyclized to pyrazole derivatives 6a-f via the reaction with hydrazine hydrate and oxalic acid in the presence of the catalytic amount of acetic acid in ethanol. Materials and Methods: The structural features of the synthesized compounds were characterized by melting point, FT-IR, 1H, 13C NMR and elemental analysis. Results: The antibacterial activities of the synthesized pyrazoles was evaluated against three gram-positive bacteria such as Enterococcus durans, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria such as Escherichia coli and Salmonella typhimurium. Conclusion: All the synthesized pyrazoles showed relatively high antibacterial activity against S. aureus strain and none of them demonstrated antibacterial activity against E. coli.

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