Advanced Materials Research Vols. 183-185

Abstract: Corn (Zea Mays L.) seedlings were in four cadmium (Cd) levels of 0-1mg/L in a hydroponic system to analyze the antioxidant enzyme system, Cd content in the shoots and roots and growth responces in the leaves of corn. There was a significant increase in malondialdehyde (MDA) concentration from Cd 0mg/L to 1mg/L, and peroxidase (POD) and catalase (CAT) activities in the leaves of corn subjected to 0-1mg/L Cd. However there was a significant decrease in superoxide dismutase (SOD) activities subjected to 0-1mg/L Cd. This indicated that Cd stress induced an oxidative stress response in corn seedlings, characterized by an accumulation of MDA, decrease in activities of SOD and increase in activities of POD and CAT. Root and leaf Cd contents of corn increased with their exposure Cd level, and the highest Cd concentration occurred in roots, followed by leaves.

Abstract: This study aims to evaluate the antioxidative activities of water and alkaline solution pH=8, 50% ethanolic (APP1 or SAPP1), 75% ethanolic (APP2 or SAPP2) and 100% ethanolic (APP3 or SAPP3) extracts of A. auricular. The antioxidant activities, including the ABTS, superoxide anion radical-scavenging effect, hydrogen peroxide radical-scavenging effect and chelating ability on ferrous ions were studied in vitro. A comparison of the 50% effective concentration (EC₅₀) values of different antioxidative reactions revealed that SAPP3 was more effective in scavenging ABTS, hydrogen peroxide and chelating ability on ferrous ions.SAPP2 showed a higher superoxide radical-scavenging activity. The alkali-soluble polysaccharides extracts showed higher radical-scavenging effect than water-soluble polysaccharides.

Abstract: In those traditional ways of treating alkali weight-reduction wastewater, the COD removal is greatly considered, while recovering terephthalic acid (TA) by valuable resource according to the principles of sustainable development is less involved. In this research, recovery of high pure TA from alkali weight-reduction has been researched by purified mother liquid with coagulation-sedimentation. The purity of TA obtained was investigated by various methods, results has shown that the characters of TA was great improved in view of high recovery rate by coagulation-sedimentation on conditions of pH 7.0-8.0 of wastewater and 200-250mg/l in quantity of PAC, so coagulation-sedimentation by pretreatment is an effective method. The study is also very useful in recycling of PET or treating TA industrial wastewater.

Abstract: In this paper, Chitosan/cellulose hybrid particle was prepared and used as absorbent for active red dye. The surface of the particle was observed by using SEM analysis. And the absorption effect was measured. The results show that the surface of the particle is porous and can effectively absorb the dye. The saturated amount reached 9mg/g when the concentration was 40mg/L.The adsorption amount decreases with the increasing of pH value of the dye solution.

Abstract: This paper studied the optimum technological parameters of the liquor which was fermented by using Phyllanthus emblica L. which was from Panzhihua Dry-hot valley as raw material and the variation of contents of nutrient elements during the process of fermentation. Adopted the orthogonal test to analyze the main factors and decided the optimum technological parameters, adopted Atomic absorption spectrometry to detect the contents of nutrient elements during the process of fermentation. The results demonstrated that when the volume of juice is 70%, the contents of SO₂ is 60 mg•kg^-1, the amount of yeast is 0.6%, and the fermentation temperature is 22°C, the concentration of alcohol can reach to 7.6%, which is the highest among the 9 test groups. The temperature is the most important factor, and the next is the volume of juice, the content of SO₂ affected little. During the process of fermentation, the proportion of most of the nutrient elements exceeded 50%, and a large part of the nutrient elements such as Ca, Cu, Fe etc. was reserved.

Abstract: We studied a novel bioflocculant poly(γ-glutamic acid) (PGA). With the addition of 4mg/L PGA (Mw=9×10⁵Da) and 12 Mm CaCl₂, the optimal temperature for flocculation performance of PGA in the kaolin suspension was about 30°C, giving the highest flocculating activity of 98%, respectively. Studies of the flocculating properties revealed that it was stable at 30-90°C and pH 7-11. With treatment of jean dyeing wastewater flocculation, PGA showed that the color, COD, NH₃-N, alkalinity and hardness removal ratios were 90%, 91.7%, 73.3%, 65 % and 86 %, respectively. Bioflocculant PGA may find possible application as an alternative for textile dyeing industry and environmental bioremediation.

Abstract: This study investigated the decolorization of Rhodamine B by the UV/Fe(III)-Oxalate and UV/Fe(III)-Penicillamine process under neutral pH. Fe(III)-Penicillamine complexes showed much higher photoactivity than that of Fe(III)-Oxalate complexes. The efficiency for decolorization of Rhodamine B at pH 5.0 was 59% and 88% in Fe(III)-Oxalate and Fe(III)-Penicillamine complexes aqueous solution after 60 min irradiation, respectively, whereas, 35% and 57% was achieved at pH 7.0. Compared to the Fe(III)/Oxalate system, the kinetic constants k_app (min^-1) for Rhodamine B decolorization in Fe(III)/Penicillamine system increased 2.4 and 2.0 times at pH 5.0 and 7.0, respectively. According to the obtained results, it was quite reasonable to conclude that penicillamine should play a similar role in Fe(III)-Penicillamine aqueous solution as oxalate did in Fe(III)-Oxalate solution. The results obtained indicated that the UV/Fe(III)-Penicillamine process was probably an alternative method to treat dye pollutant at neutral pH condition.

Abstract: Forest fire is one of the most important ecological factors in the forest ecosystem. The Great Xing’an Mountain region has not only the largest forest areas, but also the biggest forest fire burned area in China. By analyzing the recorded climate and forest fire data of Ta He forestry bureau from 1974 to 2004, the following results can be concluded: (1) There were 298 forest fires recorded by Ta He forestry bureau during 31 years and the burned area were 1.63 million hectares totally with 9.6 forest fires per year, unpredictable and short fire cycle as characters. (2) According to the occurrence time of forest fires, the Julian date concentrated between 102~181 and 240~293, corresponding April 12th to June 30th and August 28th to October 20th, which were spring and autumn fire prevention periods. Major fires mainly occurred in spring of 1974~1982, 1986~1987, 1993, and 1998~2002. The major fires cycle were 4 to 5 years. (3) The related indices of temperature, relative humidity, rainfall, and wind speed recorded in June in Ta He forestry bureau were 0.3929, 0.5274, 0.6136 and 0.1679. Temperature, relative humidity and rainfall factors in June had obvious linear relationships to forest fires, while the relationship between wind speed and forest fires is unobvious.

Abstract: The study focuses on the degradation humic acid (HA) by a hybrid system combining a flat-sheet submerged membrane module and a photocatalysis reactor (FSMPR). The influences of UV irradiation intensity, titanium dioxide (TiO₂) and initial humic acid concentration, pH, H₂O₂ dosage were investigated in batch kinetic tests. and the relevant dynamic analysis was carried out. The transmembrane pressure (TMP) with time under the range of constant flux operation (20-40L/m²h) does not increase obviously. It was also found that aeration backflush availably reduced TMP of the FSMPR. Therefore, the FSMPR can be potentially applied in drinking water treatment.

Abstract: In the present study, the in-vitro scavenging activities of hydroxyl, superoxide anion and DPPH radical of hulless barley pigment were studied. The results indicated that hulless barley pigment had excellent radical scavenging activity which was equivalent to the standard antioxidant, vitamin C. It was found that the radical scavenging effect of hulless barley pigment is gradually strengthened along with the increasing of concentration. In the range of test concentration, the maximum scavenging rate of the pigment to hydroxyl, superoxide anion and DPPH radical was 92.9%, 90.6% and 88.3% and the IC₅₀ was 4.2, 5.0 and 1.6 mg/L, respectively. Moreover, the scavenging velocity of hulless barley pigment was examined. It was observed that the radical scavenging activities of hulless barley pigment also increased with reaction time. These results suggested that colored hulless barley can be used for a new source of natural pigment with antioxidant activity.