Preparation and Properties of Sulfonated β-Cyclodextrins Used as Water-Reducer

2012 ◽  
Vol 430-432 ◽  
pp. 729-732 ◽  
Author(s):  
Sheng Hua Lv ◽  
Rui Jun Gao ◽  
Di Li
Keyword(s):  
Molecular Structure ◽  
Sulfuric Acid ◽  
Characterization Methods ◽  
H Nmr ◽  
Zeta Potentials ◽  
Potential Value ◽  
Concentrated Sulfuric Acid ◽  
Adsorption Amount ◽  
Dispersing Ability ◽  
Value Changes

Sulfonated β-cyclodextrin was synthesized with β–cyclodextrins (β-CD) and concentrated sulfuric acid. The molecular structure of sulfonated β-cyclodextrin was characterized by FTIR and 1H-NMR. The dispersing ability of sulfonated β-cyclodextrin was investigated using various characterization methods like paste fluidity, adsorption amount and zeta potentials measurements. The results show that compared with sulphonated naphthalene based superplasticizer (NPS), the fluidity of cement paste dosage with sulfonated β-cyclodextrin is 248 mm, the zeta potential value changes from 11.5 mV to-19.6 mV with the concentration of sulfonated β-cyclodextrin increasing from 0 to 15 g/L and the maximum adsorption amount is 20 mg/g. Meanwhile, FTIR and 1H-NMR results indicate that the sulfonic groups were grafted successfully on the molecular chain of the β-CD.

Synthesis, characterization and catalytic oxidation performance of new planar binuclear phthalocyanines sharing the benzene ring

2010 ◽  
Vol 14 (10) ◽  
pp. 904-910 ◽  
Author(s):  
Guiguang Lu ◽  
Yulu Zhou ◽  
Yuzhi Xiang ◽  
Daohong Xia
Keyword(s):  
Sulfuric Acid ◽  
Ammonium Molybdate ◽  
Trimellitic Anhydride ◽  
H Nmr ◽  
Immobilized Catalyst ◽  
Crude Product ◽  
Oxidation Performance ◽  
Alkaline Conditions ◽  
Concentrated Sulfuric Acid ◽  
Better Than

The crude product of hexacarboxy biphtalocyanines cobalt ( CoBPcC6 ) was synthesized by fusing trimellitic anhydride, pyromellitic dianhydride, urea and CoCl2 · 6H2O with ammonium molybdate as catalyst and then hydrolyzed under alkaline conditions. The crude product was isolated by acidifying with hydrochloric acid followed by filtration, then purified by reprecipitation from concentrated sulfuric acid followed by chromatography on silica gel column. CoBPcC6 was characterized by IR, UV-vis, 1 H NMR, elemental analysis, etc. The activity of CoBPcC6 catalyst for extractive sweetening was evaluated by studying mercaptide oxidation. It was found that the performance of this immobilized catalyst was better than the commercial immobilized catalyst.

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.

scholarly journals Manipulation of surface charges of oil droplets and carbonate rocks to improve oil recovery

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jian Hou ◽  
Ming Han ◽  
Jinxun Wang
Keyword(s):  
Zeta Potential ◽  
Oil Recovery ◽  
Carbonate Rocks ◽  
Zwitterionic Surfactant ◽  
Surface Charges ◽  
Oil Droplets ◽  
Zeta Potentials ◽  
Potential Value ◽  
Oil Water ◽  
Incremental Oil Recovery

AbstractThis work investigates the effect of the surface charges of oil droplets and carbonate rocks in brine and in surfactant solutions on oil production. The influences of the cations in brine and the surfactant types on the zeta-potentials of both oil droplets and carbonate rock particles are studied. It is found that the addition of anionic and cationic surfactants in brine result in both negative or positive zeta-potentials of rock particles and oil droplets respectively, while the zwitterionic surfactant induces a positive charge on rock particles and a negative charge on oil droplets. Micromodels with a CaCO3 nanocrystal layer coated on the flow channels were used in the oil displacement tests. The results show that when the oil-water interfacial tension (IFT) was at 10−1 mN/m, the injection of an anionic surfactant (SDS-R1) solution achieved 21.0% incremental oil recovery, higher than the 12.6% increment by the injection of a zwitterionic surfactant (SB-A2) solution. When the IFT was lowered to 10−3 mM/m, the injection of anionic/non-ionic surfactant SMAN-l1 solution with higher absolute zeta potential value (ζoil + ζrock) of 34 mV has achieved higher incremental oil recovery (39.4%) than the application of an anionic/cationic surfactant SMAC-l1 solution with a lower absolute zeta-potential value of 22 mV (30.6%). This indicates that the same charge of rocks and oil droplets improves the transportation of charged oil/water emulsion in the porous media. This work reveals that the surface charge in surfactant flooding plays an important role in addition to the oil/water interfacial tension reduction and the rock wettability alteration.

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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