Pollution abatement in the indian pulp and paper industry

Summary In this paper, pollutants in air, water and as solids which stem from the paper industry are discussed, and pollution abatement measures are suggested. The Pulp and Paper Industry is highly capital, material and energy intensive and return on investment is very low. This paper reviews some emerging international principles which are effective in reducing both effluent treatment costs per tonne of paper and the mill discharges, to levels where their environmental impacts become far less significant than at present.Mr Avijit Dey is a graduate in Chemical Engineering from Jadavpur University and at present is Design Engineer in the Paper and Process Cell of Development Consultants Ltd, 24-B Park Street, Calcutta 70016, India. Dr B. Sen Gupta is Reader in the Chemical Engineering Department of Jadavpur University, Calcutta. He obtained his BChE and PhD in Chemical Engineering from Jadavpur University and an ME in Chemical Engineering from the Indian Institute of Science, Bangalore. His research interests involve pulp and paper technology, water conservation and management, and pollution control.     

影响红沿河核电厂区热带气旋特征及最大强度估算

红沿河核电厂区位于我国北方海域的辽东湾东海岸,经常受到北上热带气旋的侵袭和影响。观测和统计表明,在辽宁登陆的热带气旋,强度能够达到台风,不容忽略。影响红沿河的热带气旋基本出现在7、8月份,以进入渤海后向西北移动和穿越山东半岛向北在辽东半岛登陆的两类热带气旋对红沿河区域影响最大,建国56年来最强的热带气旋在红沿河附近区域造成的最大风速达到25～33m/s,极大风速达40m/s以上。使用概率论方法和梯度风公式估算红沿河核电厂区可能最大热带气旋的强度参数,得到:百年一遇的可能最低气压估值为961 hPa,最大风速为35.4m/s,极大风速为46.0m/s;千年一遇的可能最低气压估值为939 hPa,最大风速为42.2m/s,极大风速为54.9m/s。     

1H NMR-based serum metabolomics analysis of the age-related metabolic effects of perinatal exposure to BPA,BPS, BPF,and BPAF in female mice offspring

Environmental Science and Pollution Research - The widespread application of bisphenols (BPs) in the industry has made them ubiquitous in the environment, causing potential environmental risks. Its...     

Classification and identification of metal-accumulating plant species by cluster analysis

Identification and classification of metal-accumulating plant species is essential for phytoextraction. Cluster analysis is used for classifying individuals based on measured characteristics. In this study, classification of plant species for metal accumulation was conducted using cluster analysis based on a practical survey. Forty plant samples belonging to 21 species were collected from an ancient silver-mining site. Five groups such as hyperaccumulator, potential hyperaccumulator, accumulator, potential accumulator, and normal accumulating plant were graded. For Cd accumulation, the ancient silver-mining ecotype of Sedum alfredii was treated as a Cd hyperaccumulator, and the others were normal Cd-accumulating plants. For Zn accumulation, S. alfredii was considered as a potential Zn hyperaccumulator, Conyza canadensis and Artemisia lavandulaefolia were Zn accumulators, and the others were normal Zn-accumulating plants. For Pb accumulation, S. alfredii and Elatostema lineolatum were potential Pb hyperaccumulators, Rubus hunanensis, Ajuga decumbens, and Erigeron annuus were Pb accumulators, C. canadensis and A. lavandulaefolia were potential Pb accumulators, and the others were normal Pb-accumulating plants. Plant species with the potential for phytoextraction were identified such as S. alfredii for Cd and Zn, C. canadensis and A. lavandulaefolia for Zn and Pb, and E. lineolatum, R. hunanensis, A. decumbens, and E. annuus for Pb. Cluster analysis is effective in the classification of plant species for metal accumulation and identification of potential species for phytoextraction.     

巢湖水质时空分布模式研究

依据2004~2006年12个采样点11个水质指标数据,应用主成分分析(PCA)、聚类分析(CA)、判别分析(DA)和基于G IS平台的克里格插值法,对巢湖水质时空分布模式进行研究。通过统计分析将巢湖11个水质指标概括为4个主成分:第一主成分COD、BOD5和Chl-a;第二主成分电导率、NH4+-N、TN和TP;第三主成分温度和DO;第四主成分pH和SD。在空间尺度上分为2组,分别对应于东西半湖。除了DO指标,空间上西半湖周边区域的水质指标浓度显著高于东半湖;东西半湖TP和COD空间分布相似;在时间尺度上,可分为1月~3月份、12月份一组和4月~11月份一组;TP、COD、DO和SD指标第一时期浓度高于第二时期,温度、电导率和Chl-a指标则相反;溶解氧和温度两者的时间差异性呈现明显的负相关。并对采样点和采样频次进行了适当优化。     

基于电涡流效应的钢质体应变实时检测技术研究

为避免特种设备中的钢质体结构因交变载荷过大而产生应变,从而造成局部区域应力集中、降低钢质体强度和承压能力,提出1种利用涡流效应评价钢质体应变状态方法,并研制出由涡流探头和信号处理系统组成的应变检测装置。利用万能拉伸机对Q235钢试件进行拉伸应变实验,分析电压有效值、拉力值随采样时间的变化规律,进而得到相关线性方程。研究结果表明：该装置能够敏感检测出钢质体不同应变阶段,且在弹性阶段内可通过直线拟合方程定量检测应变量。因此,可有效预防因应变过大而造成的钢质体结构失效,从而避免特种设备危险事故发生,一定程度上保护人们生命及财产安全。     

Advanced oxidation process: a sustainable technology for treating refractory organic compounds present in industrial wastewater

Environmental Science and Pollution Research - The world faces tremendous challenges and environmental crises due to the rising strength of wastewater. The conventional technologies fail to achieve...     

Impact of environmental concentrations of beta-cypermethrin on the antioxidant system in the brain and liver of zebrafish (Danio rerio)

Beta-cypermethrin (beta-CYP) is a widely used pyrethroid pesticide, the extensive application of which may potentially cause damage to non-target organisms. To investigate the effect of beta-CYP on the antioxidant system of aquatic animals, adult zebrafish were exposed to environmentally relevant dosages (0.01, 0.1 and 1.0 μg/L) of beta-CYP. The activities of four antioxidant enzymes in zebrafish liver and brain tissue were tested after 7, 15 and 30 days of exposure. Our results showed that exposure of beta-CYP could induce different levels of increase in hepatic superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPx) activities at 7 and 15 days post exposure (dpe), but caused apparent inhibition of hepatic SOD, GR and GPx activities at 30 dpe. Unlike in liver tissue, SOD and CAT activities in zebrafish brain did not show any apparent response to beta-CYP during the whole treatment period. In addition, increased brain GPx activities were observed at 7 and 30 dpe.     

Flow cytometric analysis of fish leukocytes as a model for toxicity produced by azadirachtin-based bioagrocontaminant

Azadirachtin is one of the most promising natural biopesticide used to overcome the hazardous effects of different organic pesticides and believed to be more environmentally friendly due to the unique nature of biodegradability. In the present study, the impact of no-observed-effect level (NOEL) dose of an azadirachtin-based bioagrocontaminant, Neemsheild, on the blood profile of Indian major carp, Labeo rohita, was examined. The 96-hr LC₅₀ value of Neemsheild was found to be 44.61 ppm. The total erythrocyte count (TEC), hematocrit (Hcrt), and Hb (hemoglobin) values showed a gradual decrease throughout the experimental period, whereas total leukocyte count (TLC) showed an initial increase followed by decline. Flow cytometric analysis subdivided the entire leukocyte population into four separate groups: thrombocytes together with small lymphocytes, monocytes, neutrophils, and basophils. The fluctuation in leukocyte subpopulation indicated an immunotoxicological effect due to azadirachtin. Clustering of different cell types and similarity percentage values were found to differ greatly from control. It was evident from the study that the cell population comprising small lymphocytes and thrombocytes indicated predominant changes as physiological response of fish to different doses of azadirachtin. Thus, flow cytometric analysis of leukocyte populations may be considered as a biomarker to assess fish toxicity.