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In this paper, montmorillonite-Cu(II)/Fe(III) oxides magnetic material was prepared and used for removal of harmful algae from water. The material was prepared by the supporting of Cu(II)/Fe(III) oxides on pillared montmorillonite and was characterized by XRD, zeta potential measurements. The results showed that the whole material is magnetic. The prepared magnetic material was effective for the removal of cyanobacterial Microcystis aeruginosa and the loaded particles was chemically regenerated using acetone solution.

Two modified polymer flocculants of PDADMA salts, PDADMA nitrate (PDADMAN) and PDADMA sulfate (PDADMAS), were prepared from the most widely used commercial product of polydiallyldimethylammonium chloride (PDADMAC). Solution properties such as conductivity and viscosity were investigated, showing that the conductivity follows the order of PDADMAS > PDADMAC > PDADMAN, while the reduced viscosity increases in the order of PDADMAS < PDADMAC < PDADMAN. The results indicate that, compared with PDADMAC, PDADMAN has a more cationic density and a more extended polymer chain, whereas PDADMAS exhibits a smaller coiled polymer size because of the stronger charge affinity of sulfate ion to the polycation of PDADMA. Flocculation experiments were performed on kaolin suspensions. It was found that PDADMAN is the most efficient in turbidity removal, while PDADMAS has wider optimum dosages, larger floc size and more rapid settling rate. Atomic force microscopy (AFM) was employed for imaging the adsorption structures of the three polymers on the negatively charged mica surface. Remarkable differences in molecular conformation were observed. Compared with the pearl necklace-like aggregation of hemispheroids of PDADMAC polymer, PDADMAN takes a sponge-like thin layer structure and PDADMAS exhibits a uniform hemispherical structure.The above differences in both the solution property and the adsorption and flocculation behaviors are attributable to counterion effects. Different counterions may lead to different adsorption and flocculation mechanisms that PDADMAN adopts a flat and layer-layer adsorption without loops and tails extended from the surface, implying that a charge neutralization mechanism plays more roles, while adsorbed PDADMAS is in the form of coiled spheres with loops and tails so that a bridging mechanism is more involved. Namely, it is the adsorption structure and morphology of the polymer flocculants that is the main factor influencing the flocculation mechanism.

Euphorbia helioscopia L. (Euphorbiaceae), a Chinese medicinal herb, is widely distributed in most parts of China [1]. Phytochemical studies show that Euphorbia helioscopia L. contains mainly terpenoids [2,3], flavonoids [4,5], and polyphenols [6], but few papers report the tannins, alkaloids, and lignans isolated from this plant. Previously, the high contents of quercetin, a plant-derived flavonoid, have been detected in the leaves of Euphorbia helioscopia >7@ and its anticancer properties were demonstrated [8]. Previous experiments [9] studied the antitumor activity of different extracts of Euphorbia helioscopia L. on human hepatocellular carcinoma cell lines SMMC-7721, BEL-7402, and HepG2, gastric carcinoma cell line SGC-7901, and colorectal cancer cell line SW480, and the result have shown that the ethyl acetate extract (EAE) was the main active extract with antitumor effect. In order to evaluate the chemical constituents of the anticancer active fraction, we studied the chemical constituents of the EAE of E. helioscopia. One tannin, two alkaloids, one lignan, four flavonoids, and two phenolic acids compounds were isolated from the EAE of E. helioscopia.Ten known compounds 1-10 were obtained from the EAE by repeated chromatographic methods. The structures were elucidated on the basis of chemical evidence, extensive spectroscopic analysis, and comparison with the literature data. The compounds were identified as follows: 3,3c-di-O-methylellagic acid-4c-O-E-D-glucopyranoside (1) >10@, flazine (2) >11@, N-acetyltryptophan (3) >12@, pinoresinol (4) >13@, protocatechuic acid (5) >5@, gallic acid (6) >14@, quercetin (7) >14@, hyperoside (8) >14@, quercetin-3-O-E-D-glucopyranoside (9) >3@, and myricetin (10) >14@.General Experimental Procedures. NMR spectra were recorded on an INOVA-600 spectrometer ( 1 H: 600 MHz and 13 C: 150 MHz) with TMS as internal standard. UV spectra were obtained on a Shimadzu UV-160 spectrophotometer. HR-ESI-MS were recorded on an APEX II FT-ICR mass spectrometer. Column chromatography was carried out with Sephadex LH-20 (Pharmacia Biotech Company, Sweden), and silica gel (100-200 and 200-300 mesh, Qingdao Extraction and Isolation. The dried whole plant of E. helioscopia L. (3 kg) was extracted three times (2, 2, 1 h) with water (14 times volume) and then filtered. The filtrate was concentrated to a small volume at room temperature. The residue was precipitated with 70% ethanol and allowed to stand for about 24 h at room temperature and then filtrated. The filtrate was evaporated under reduced pressure using a rotary evaporator (BUCHI, Switzerland) to give the crude extract (300 g). The crude extract was dissolved in water and fractionated using petroleum ether, chloroform, ethyl acetate, and n-butanol, successively. Portions of the extracts of each fractionation step were evaporated to dryness under vacuum. The EAE (36.7 g) was chromatographed on a silica gel column eluting with a methylene chloride-methanol gradient (36:1-1:1) to give eleven fractions (E1-E11). Fractions E5 and E6 were suc...