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...

In order to find the most effective method to overcome seed dormancy in Teucrium chamaedrys  L. medicinal plant species the effect of some chemical and physical breaking methods including: cold stratification (5 °C), scarification with sandpaper, stratification with needle, concentrated sulfuric acid, gibberellic acid and combination of these methods were investigated. Treated seeds along with ...

In scale-up, the potential of ethanol production by dilute sulfuric acid pretreatment using corncob was investigated. Pretreatments were performed at 170 °C with various acid concentrations ranging from 0% to 1.656% based on oven dry weight. Following pretreatment, pretreated biomass yield ranged from 59% to 67%. More than 90% of xylan was removed at 0.828% of sulfuric acid. At same pretreatmen...

Introduction Sulfuric acid was first assessed to be carcinogenic in 1997 in a report of the World Health organization WHO (IARC). Based on this report, the Senate committee dealing with the control of harmful substances in the workplace submitted the first proposal justifying a lower occupational exposure limit [2].This proposal contained a list of many individual studies. In the investigations...

strong sulfuric acid solutions, and can be measured by a fluorometer.1) Gotelli et al.2) and Shihabi et al.3) have used high-performance liquid chromatography (HPLC) to separate fluorescent derivatives, and have measured cortisol levels in serum and urine. Since the sulfuric acid-induced fluorescence is unstable, it is necessary to inject the reaction mixture into HPLC immediately after the for...

We have studied the hydration of sulfuric acid – ammonia and sulfuric acid – dimethylamine clusters using quantum chemistry. We calculated the formation energies and thermodynamics for clusters of one ammonia or one dimethylamine molecule together with 1–2 sulfuric acid and 0–5 water molecules. The results indicate that dimethylamine enhances the addition of sulfuric acid to the clusters much m...

The preparation of 5-bromo-2-naphthol (4) in three steps from 5-amino-2-naphthol (1) is described. A sulfonic acid group is introduced at the 1-position as an activating and protecting group for the Sandmeyer reaction. The sulfonate group allows for the use of only water and sulfuric acid as solvents. The sulfonic acid is introduced with three equivalents of sulfuric acid, and it is removed in ...

This paper describes the effect of the addition of Tween-80 in dilute sulfuric acid pretreatment on enzymatic hydrolysis of waste office paper. Lignocellulosic material was pretreated with dilute sulfuric acid (1% V/V) at 50 oC for 3 hours, with or without addition of Tween-80 (2.5 g/L). The pretreatment was able to remove hemicellulose and lignin from waste office paper, but the surfactant did...

To determine cholesterolin biologicalfluids,use of the ferric chloride-sulfuric acid reagent introduced by Zlatkis et al. (1) is relatively simple and reliable (2, 3), and the sensitivityof the reagent for cholesterol is four to five times greater than that of the Liebermann-Burchard reagent (2). However, Parekh and Jung (4) reported that hydrogen chloride is evolved during the ferric chloride-...

Molecular dynamics method is applied to study the structure of stable sulfuric acid–water clusters at various compositions. Also a planar liquid–vapor interface is studied. Two different potential models were used. In the simpler model, sulfuric acid (H 2 SO 4 ) remains in an undissociated state. A more realistic scheme requires that in the presence of water (H 2 O) H 2 SO 4 protonates to form ...