The behaviour of the lead-aqueous sulfate electrode in relation to the development of electric vehicle batteries

1980 ◽  
Vol 33 (6) ◽  
pp. 1187 ◽  
Author(s):  
DB Matthews ◽  
RW Garrad
Keyword(s):  
Sulfuric Acid ◽  
Ammonium Sulfate ◽  
Lead Sulfate ◽  
Electrolyte Composition ◽  
Cyclic Voltammograms ◽  
Sulfate Electrolyte ◽  
Lead Acid Battery ◽  
Concentrated Sulfuric Acid ◽  
Lead Electrodes ◽  
Charge Discharge

The behaviour of smooth lead electrodes in various aqueous sulfate electrolytes has been studied by slow scan (10 mV min-1) cyclic voltammetry and coulometry and by scanning electron microscopy. The dependence of the amount of charge that can be delivered in discharge of lead to form lead sulfate, as in a lead-acid battery, is found to depend strongly on electrolyte composition, and an acidic ammonium sulfate electrolyte (0.5 mol dm-3, pH 2.0) was found to yield the highest charge over some 40 charge-discharge cycles when compared with various other sodium sulfate, ammonium sulfate and sulfuric acid electrolytes. The quantity of charge was directly related to the size of the lead sulfate crystals produced. This result is interpreted in terms of the passivating effect of lead sulfate. A tentative mechanism for the anodic formation of lead sulfate is proposed and used to interpret the cyclic voltammograms obtained in concentrated sulfuric acid.

Gallium Arsenide Integrated Circuits Decapsulation Technique Using Mixed Acid Chemistry For Die-Level Failure Analysis

2018 ◽  
Author(s):  
Harold Jeffrey M. Consigo ◽  
Ricardo S. Calanog ◽  
Melissa O. Caseria
Keyword(s):  
Gallium Arsenide ◽  
Sulfuric Acid ◽  
Nitric Acid ◽  
Integrated Circuits ◽  
Failure Analysis ◽  
Mixed Acid ◽  
Optimum Parameters ◽  
Plastic Package ◽  
Fuming Nitric Acid ◽  
Concentrated Sulfuric Acid

Abstract Gallium Arsenide (GaAs) integrated circuits have become popular these days with superior speed/power products that permit the development of systems that otherwise would have made it impossible or impractical to construct using silicon semiconductors. However, failure analysis remains to be very challenging as GaAs material is easily dissolved when it is reacted with fuming nitric acid used during standard decapsulation process. By utilizing enhanced chemical decapsulation technique with mixture of fuming nitric acid and concentrated sulfuric acid at a low temperature backed with statistical analysis, successful plastic package decapsulation happens to be reproducible mainly for die level failure analysis purposes. The paper aims to develop a chemical decapsulation process with optimum parameters needed to successfully decapsulate plastic molded GaAs integrated circuits for die level failure analysis.

PRODUCTION OF SULFOCATIONITE BY MODIFICATION OF NATURAL COAL WITH CONCENTRATED SULFURIC ACID

2020 ◽  
Vol 3 (441) ◽  
pp. 104-109
Author(s):  
N.A. Bektenov ◽  
◽  
N.C. Murzakassymova ◽  
M.A. Gavrilenko ◽  
А.N. Nurlybayeva ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Concentrated Sulfuric Acid ◽  
Natural Coal

Addition of primary alcohols to 3-chlorononafluoro-1,5-hexadiene and perfluoro-1,3,5-hexatriene

1985 ◽  
Vol 50 (8) ◽  
pp. 1714-1726 ◽  
Author(s):  
Václav Dědek ◽  
Igor Linhart ◽  
Milan Kováč
Keyword(s):  
Sulfuric Acid ◽  
Primary Alcohols ◽  
Principal Product ◽  
Allyl Rearrangement ◽  
Concentrated Sulfuric Acid ◽  
Sodium Alkoxide

Sodium alkoxide-catalyzed addition of methanol, ethanol and propanol to 3-chlorononafluoro-1,5-hexadiene (I) proceeds at temperatures -35 °C to 8 °C with allyl rearrangement, affording 1,6-dialkoxy-1,1,2,3,4,4,5,6,6-octafluoro-2,4-hexadiene (V) as the principal product, along with 1,6-dialkoxy-1,2,3,3,4,5,6,6-octafluoro-1,5-diene (VI) and trans-1,6-dialkoxy-1,1,2,3,4,4,5,6,6-nonafluoro-2-hexene (VII). The ethers Va-Vc consist of the cis,trans- and trans,trans-isomers in about 3 : 1 ratio, whereas the ethers VIa-VIc have trans,trans-configuration. Ethers Vc and VIc react with concentrated sulfuric acid to give dipropyl 2,3,4,5-tetrafluoro-2,4-hexadienedioate (IX) and dipropyl 2,3,4,4,5-pentafluoro-2-hexenedioate (X), respectively, whereas the ether VIIc affords a mixture of propyl 6-propyloxy-2,3,4,4,5,6-heptafluoro-2-hexenoate (XI) and ester X. Addition of methanol to perfluoro-1,3,5-hexatriene (II) affords 1,1,2,3,4,5,6,6-octafluoro-1,6-dimethoxy-3-hexene (XIII) as the principal product.

scholarly journals 4,5,6-Trichloropyrimidine-2-carboxamide

Molbank ◽  
10.3390/m1190 ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. M1190
Author(s):  
Andreas S. Kalogirou ◽  
Panayiotis A. Koutentis
Keyword(s):  
Sulfuric Acid ◽  
Elemental Analysis ◽  
Maldi Tof ◽  
Concentrated Sulfuric Acid

Reaction of 4,5,6-trichloropyrimidine-2-carbonitrile (1) with concentrated sulfuric acid at ca. 20 °C gave 4,5,6-trichloropyrimidine-2-carboxamide (5) in 91% yield. The new compound was fully characterized by IR, MALDI-TOF, NMR and elemental analysis.

Regioselective Bromination of Anilines in the Presence of Nitrosonium Hydrogensulfate in Concentrated Sulfuric Acid

1995 ◽  
Vol 5 (2) ◽  
pp. 65-66 ◽  
Author(s):  
Mikhail V. Gorelik ◽  
Vera I. Lomzakova ◽  
Elena A. Khamidova ◽  
Vitalii Ya. Shteiman ◽  
Marianna G. Kuznetsova ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Concentrated Sulfuric Acid
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