Effect of Poly(Acrylic Acid) Based Polymer Flocculants on Sedimentation of Surface Water

In most scenarios, there tend to have some impurities such as organic and inorganic substances found on the surface water. These impurities can be classified as insoluble and soluble compounds which in turn, can be purified by filtration and sedimentation prior used. Calcium carbonate (CaCO3), is one of the most contaminated compounds on surface water, mainly causes severe damage to industrial parts. Therefore, CaCO3 need immediate removal from raw water before applied to an unit operation by coagulation and flocculation. We mainly focused on precipitation of synthetic water and raw water with polyaluminium chloride (PAC) and synthetic polymer flocculants in this research study. The synthetic flocculants of Polyacrylic acid (PAA), Polyacrylamide (PAM) and Poly (acrylic acid-co-acrylamide) (PAAAM) by free radical polymerization in aqueous. The PAAAM is synthesized in various mole ratio of acrylic acid and acrylamide of 9:1 to 5:5. The polymer flocculants are characterized by FT-IR and 1H-NMR techniques. The FTIR spectra of the sample showed absorption frequency above HYPERLINK "tel:3200-3000" \t "_blank" 3200-3000, 1750-1550 and 1650-1500 corresponding to OH and CO stretching and NH bending respectively. The 1H-NMR spectra of PAM showed chemical shift at 1.50, 2.10 and 4.20 ppm regarding to proton of methyl, methylene and amide group respectively and the present of proton resonances at 1.50 and 2.30 ppm regarding to proton of methyl and methylene of PAA. The removal efficiency of suspended CaCO3 is measured and calculated via turbidity technique. The dosage of PAC 0.1 ppm can remove suspended CaCO3 approximately 65.33% after the PAAAM with mole ratio of 8:2 is applied to system lead to the removal efficiency increasing to 99.03%.

Binaphthyl-Based Macrocycles as Optical Sensors for Aromatic Diphenols

The synthesis of several rigid, homochiral organic macrocycles possessing, respectively, average molecular D2 and D3 symmetries, is described. They have been obtained from aromatic dicarboxylic acids, in combination with an axially-chiral, suitable dibenzylic alcohol, derived from 1,1′-binaphthyl-2,2′-diol (BINOL) using one-pot esterification reactions in good isolated yields. NMR and circular dichroism (CD) spectroscopies detect the structural and shape variability in the scaffolds, reflected both in terms of the changes in chemical shifts and the shape of selected proton resonances, and in terms of the variation of the CD signature related to the dihedral angle defined by the binaphthyl units embedded in the rigid cyclic skeleton. The D2 cyclic adducts are able to form stable complexes with aromatic diphenols, with binding strengths that are dependent on small variations in the spacing units, and therefore on the shapes of the internal cavities of the cyclic structures.

Isomeric 26Al beam production with CRIB

We performed an experiment to measure proton resonant elastic scattering of a mixed 26m,gAl beam with a thick target in inverse kinematics by using CNS RI beam sep-arator, located at RIKEN Nishina Center. It aimed to search for strong proton resonances and determine level properties of low spin-parity states in 27Si. Diagnosis of the 26mAl purity of the beam by annihilation radiation are discussed.