EPR analysis of the dosimetric properties of sulfamic acid irradiated by different ionizing radiations for radiotherapy and hadrontherapy applications

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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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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Zinc Sulfamate Catalyzed Efficient Selective Synthesis of Benzimidazole Derivatives under Ambient Conditions

Letters in Organic Chemistry ◽

10.2174/1570178616666181211094040 ◽

2019 ◽

Vol 16 (9) ◽

pp. 740-749

Author(s):

Sushil R. Mathapati ◽

Arvind H. Jadhav ◽

Mantosh B. Swami ◽

Jairaj K. Dawle

Keyword(s):

Benzimidazole Derivative ◽

Sulfamic Acid ◽

Aromatic Aldehydes ◽

Catalytic Amount ◽

Product Yield ◽

Lewis Acidity ◽

Benzimidazole Derivatives ◽

Ambient Conditions ◽

Reaction Condition ◽

Green Approach

Zinc sulfamate (Zn(NH2SO3)2 is a derivative of sulfamic acid (H3NSO3) which possesses “Lewis acidity” and finds well suited in a number of catalytic applications. The present paper describes an efficient, eco-friendly, and clean synthesis of 2-substituted benzimidazole derivatives by reacting diverse o-phenylenediamine with various substituted aromatic aldehydes using a catalytic amount of zinc sulfamate in ethanol at ambient temperature. As a result, 10 mol.% of Zinc sulfamate catalyst showed 92% of respective product yield with 100% conversion using short reaction period in ethanol. Meanwhile, effect of reaction parameters, such as amount of catalyst, different solvents, and reaction temperature on reaction product, was also studied. In addition, in the optimized reaction condition various substituted biological important benzimidazoles derivatives were prepared by using optimized reaction condition in good to efficient yield. In addition, possible reaction mechanism in the presence of zinc sulfamate for the preparation of benzimidazole derivative was sketched and discussed. The present green approach showed significances with faster reaction rate with inexpensive catalyst, which showed excellent and clean yield of benzimidazole in mild reaction condition with easy work-up procedure.

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Boehmite Silylpropyl Amine Sulfamic Acid as an Efficient and Recyclable Catalyst for the Synthesis of some Pyrazole Derivatives

Letters in Organic Chemistry ◽

10.2174/1570178614666170505113009 ◽

2017 ◽

Vol 14 (6) ◽

Cited By ~ 2

Author(s):

Rahele Doosti ◽

Mohammad Bakherad ◽

Mahdi Mirzaee ◽

Khosrow Jadidi

Keyword(s):

Sulfamic Acid ◽

Recyclable Catalyst ◽

Pyrazole Derivatives

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Sulfamic Acid-catalyzed One-pot Multicomponent Synthesis of 5-phenyl-2- thioxo-1,2,3,5-tetrahydro-4H-pyrimido[4,5-d][1,3]thiazolo[3,2-a]pyrimidin- 4-ones

Current Green Chemistry ◽

10.2174/2213346103666161115124757 ◽

2017 ◽

Vol 3 (3) ◽

pp. 227-234 ◽

Cited By ~ 2

Author(s):

Sunetra Jadhav ◽

Ajinkya Patravale ◽

Reshma Patil ◽

Digambar Kumbhar ◽

Vishram Karande ◽

...

Keyword(s):

Sulfamic Acid ◽

Multicomponent Synthesis ◽

One Pot ◽

Acid Catalyzed

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Food irradiation: Effect of ionizing and non-ionizing radiations on preservation of fruits and vegetables– a review

Trends in Food Science & Technology ◽

10.1016/j.tifs.2021.06.002 ◽

2021 ◽

Author(s):

Bhawna Bisht ◽

Pooja Bhatnagar ◽

Prateek Gururani ◽

Vinod Kumar ◽

Mahipal Singh Tomar ◽

...

Keyword(s):

Fruits And Vegetables ◽

Food Irradiation ◽

Irradiation Effect ◽

Ionizing Radiations

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PO-1078 Ionizing radiations sustain Glioblastoma cell dedifferentiation to a stem phenotype through Survivin

Radiotherapy and Oncology ◽

10.1016/s0167-8140(15)41070-9 ◽

2015 ◽

Vol 115 ◽

pp. S582

Author(s):

P. Dahan ◽

J. Martinez Gala ◽

C. Delmas ◽

S. Monferran ◽

L. Malric ◽

...

Keyword(s):

Glioblastoma Cell ◽

Cell Dedifferentiation ◽

Ionizing Radiations

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Sulfamic acid pyromellitic diamide-functionalized MCM-41 as a multifunctional hybrid catalyst for melting-assisted solvent-free synthesis of bioactive 3,4-dihydropyrimidin-2-(1H)-ones

Scientific Reports ◽

10.1038/s41598-021-89572-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ehsan Valiey ◽

Mohammad G. Dekamin ◽

Zahra Alirezvani

Keyword(s):

Structural Characteristics ◽

Biginelli Reaction ◽

High Surface ◽

High Surface Area ◽

Sulfamic Acid ◽

Solvent Free ◽

Biologically Active ◽

Green Protocol ◽

Solvent Free Conditions ◽

Mcm 41

AbstractThis study introduces a practical approach to fabricate a novel hybrid acidic catalyst, namely sulfamic acid pyromellitic diamide-functionalized MCM-41 (MCM-41-APS-PMDA-NHSO3H). Various techniques such as FTIR, TGA, XRD, BET, FESEM, and EDX were used to confirm its structural characteristics. The efficiency of the new MCM-41-APS-PMDA-NHSO3H organosilica nanomaterials, as a heterogenous nanocatalyst, was examined in the synthesis of biologically active 3,4-dihydropyrimidin-2-(1H)-one derivatives under solvent-free conditions. It was found that the nanoporous MCM-41-APS-PMDA-NHSO3H, demonstrating acidic nature and high surface area, can activate all the Biginelli reaction components to afford desired 3,4-dihydropyrimidin-2-(1H)-ones under solvent-free conditions in short reaction time. Furthermore, easy and quick isolation of the new introduced hybrid organosilica from the reaction mixture as well as its reusability with negligible loss of activity in at least five consecutive runs are another advantages of this green protocol.

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