A novel kind of spherical cellulose nanocrystal (SCNC) suspension was prepared by hydrolysis of microcrystalline cellulose with a mixture of sulfuric acid and hydrochloric acid under ultrasonic treatment. The mechanism of SCNC formation and the liquid crystalline properties of their suspensions were investigated. A suspension of spherical particles was usually inclined to form crystallization c...

Introduction: Geologic evidence indicates that the K/T mass extinction occurred on 65 million years ago is caused by an asteroid or comet impact [e. g., 1]. However, the actual mechanism that caused the mass extinction is still very controversial. The impact generated sulfuric oxides are thought to cause an environmental perturbation and it is one of the most plausible hypotheses of the K/T kil...

Recent ab initio calculations showed that amines can enhance atmospheric sulfuric acid-water nucleation more effectively than ammonia, and this prediction has been substantiated in laboratory measurements. Laboratory studies have also shown that amines can effectively displace ammonia in several types of ammonium clusters. However, the roles of amines in cluster formation and growth at a micros...

Dicarboxylic organic acids have properties that differ from those of sulfuric acid during hydrolysis of lignocellulose. To investigate the effects of different acid catalysts on the hydrolysis and degradation of biomass compounds over a range of thermochemical pretreatments, maleic, oxalic and sulfuric acids were each used at the same combined severity factor (CSF) values during hydrolysis. Xyl...

Fuel ethanol can be produced from bamboo by concentrated sulfuric acid hydrolysis followed by continuous ethanol fermentation. To reduce the environmental impact of this process, treatment of the stillage, reuse of the sulfuric acid and reduction of the process water used were studied. The total organic carbon (TOC) concentration of stillage decreased from 29,688 to 269 mg/l by thermophilic met...

This study addresses the feasibility of removing Cu and Ni from sludges of printed circuit board (PCB) plants by acidic extraction. Citric acid, acetic acid, hydrochloric acid, nitric acid, and sulfuric acid at various concentrations were experimentally examined to determine preferred conditions for removing Cu and Ni. Experimental results indicate that the removal ratios of Cu were 57% (citric...

As demonstrated in a number of investigations, gaseous sulfuric acid plays a central role in atmospheric aerosol formation. Using chemical ionization mass spectrometer the gas-phase sulfuric acid and OH concentration were measured in Hyytiälä, SMEAR II station, Southern Finland during 24 March to 28 June 2007. Clear diurnal cycles were observed as well as differences between new particle format...

1.1 Manufacturing processes Major industries with exposure to strong inorganic acid mists include those that manufacture phosphate fertilizer, isopropanol (isopropyl alcohol), synthetic ethanol (ethyl alcohol), sulfuric acid, nitric acid, and lead batteries. Exposure also occurs during copper smelting, and pickling and other acid treatment of metals (Suresh, 2009). Minor uses of sulfuric acid i...

Developing sustainable chemical methods to synthesize silver nanoparticles has drawn significant research interest. Due to their unique and well-defined physical-chemical properties, cellulose nanocrystals (CNCs) have become one of the most promising renewable nanomaterials. Here we use CNC to mediate silver nanoparticle synthesis and elucidate the effect of CNC surface chemistry (as defined by...

Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional...