Treatment of sugar industry wastewater using a combination of thermal and electrocoagulation processes

Sugar industries require a large amount of water for processing, and also generate large amounts of high-degree polluted wastewater. To maintain the water balance in the industry, it is imperative that effective treatment methods need to be devised to treat the wastewaters. The main aim of the present work is to treat the sugar industry wastewater by combined thermal and electro-oxidation methods with a metal and a catalyst based on ferrous material. Results showed a reduction of 75.6% of COD and 79.2% of colour content with thermal treatment, and 97.8% of COD and 99.7% of colour with combined thermal and electrocoagulation treatments under optimum conditions. These reduction levels are adequate for recycling limits.     

Problems of livestock development in the Himalayan region

Summary This paper outlines the complexities and problems of animal husbandry in the Himalayas of India. In particular, the climatic influences of temperature, rainfall and humidity are emphasised. A wide range of possible improvements to decrease livestock malnutrition and mortality are proposed.Dr J.C. Biswas, BSc, MVSc, works in the Animal Genetics and Breeding Laboratory; Dr R. Somvanshi, MVSc, FRCVS (Sweden) is Veterinary Pathologist in charge of the Clinical Pathology and Medicine Section in Livestock Production Research and Lt.Col. Dr G.S.C. Ranga Rao, MVSc, is Veterinary Parasitologist and Joint Director. All three work at the Indian Veterinary Research Institute.     

Diet and Nutrition during Drought-An Indian Experience

In 1987 India experienced one of the century's worst droughts with two-thirds of its sown area receiving 'scanty' or 'deficient' rainfall. Delayed rains in some parts, though to some extent they relieved the water scarcity, did not brighten the prospects of agricultural production. In order to assess the diet and nutritional situation of the vulnerable population in the severely affected areas, rapid surveys were undertaken by the National Institute of Nutrition, Hyderabad, in five States of the country, namely Andhra Pradesh, Tamil Nadu, Karnataka, Orissa and Gujarat, during the months of October-December 1987. Results obtained during the current surveys are compared with the dietary situation observed in earlier droughts in the 1960s and 1970s, and it is concluded that the widespread hunger and its consequences encountered in earlier droughts could be averted, due mainly to the better food security and distribution mechanisms now available in the country.     

Microbial ecology of the soils of Indian desert

A comprehensive study on the microbial ecology of Indian desert soils was carried out. Although different groups of microorganisms e.g., fungi, actinomycetes, bacteria, Azotobacter and nitrifying bacteria were present, but in relatively low numbers, there was considerable variation in numbers from one site to another within the desert as the physicochemical characters of the soils varied. Actinomycetes formed a high proportion of the total microflora. In the majority of the soils, 80% of the fungal population belonged to the genera Aspergillus and Penicillium, while Gram-positive spore formers were the dominant group among bacteria. No significant decline in the population of microorganisms was observed during summer, in spite of high surface soil temperatures. Microbiological properties of these soils also varied depending on the type of land use pattern: grasslands, in general, supported higher numbers of microorganisms than three plantations, cultivated fields or barren land. Stabilization of shifting and sand dunes introduction of vegetation has markedly increased the soil microflora. In general the low organic matter content and poor moisture availability of desert soils were the major factors limiting optimum microbial activity.     

中国红色粘土型金矿成矿特征

中国的红色粘土型金矿是 90年代初发现并开始研究的 ,基本上产于南方特别是西南地区。由于特殊的地质构造条件和气候、地貌条件 ,该类型金矿与国外的红土型金矿存在明显的差异 :红色粘土型金矿剖面发育差 ,红土化程度低 ;对源岩依存度高 ;铁铝含量低、硅含量高 ;矿石处在富粘土矿物阶段 ,少见三水铝石 ,一般为伊利石和高岭石共存。金在红色粘土中以微细粒分散形式存在 ,且在红色粘土剖面中由于表生淋滤作用而发生活化、迁移和再沉淀。     

Control of distal retinal pigment migration in the fiddler crab Uca pugilator

Several concentrations of extracts prepared from the eyestalks of a specimen of Uca pugilator were injected into other U. pugilator individuals. The distal pigment of the eyes first became light adapted and then dark adapted, the whole process lasting 6 h. The mean integrated response for light adaptation increased progressively up to the highest tested extract (3 eyestalk equivalents/dose), but with the darkadapting response the maximal effect was produced by the extract containing 2 eyestalk equivalents/dose. Gel filtration of eyestalk extracts in Sephadex G-50 showed that the fractions associated with greatest light adaptation were also associated with greatest pigment dispersion in the melanophores. Almost no light or dark adaptation of the retinal pigment resulted from injections of eyestalk extracts treated with -chymotrypsin which supports the interpretation that these substances are polypeptides of neurosecretory origin.Supported by Grant GB-7595 X from the National Science Foundation.     

Downcore sulphur isotope ratios and diatom inferred pH in an artificially acidified Canadian shield lake

Three gravity cores were removed from near the deepest point in Lake 223 on 9 June 1984, eight years after the Experimental Lakes Area (ELA) staff began the artificial acidification of the lake with sulphuric acid. The first of these cores was analysed for diatoms and pollen stratigraphy while the second and third were analysed for downcore sulphur isotope ratios (H. Thode) and downcore changes in sulphur reducing bacterial densities (S. Rao). Sediment core chronologies were based on lead-210 and cesium-137 data (R. Anderson) and the Ambrosia pollen rise (M. Dickman). Analysis of the first core to the depth of the Ambrosia pollen rise (9 cm) indicated that diatom inferred pH in Lake 223 at the time of the Ambrosia rise (circa 1890) was 6.8-7.0. At a sediment depth of 3 cm the diatom inferred pH was 6.7. Thereafter diatom inferred pH began a decline culminating in the present day (observed) pH range for 1984 (5.3-5.5). At a sediment depth of 1 cm, an increase in the abundance of two benthic alkalophilic diatoms occurred. The increase in the abundance of these diatoms was ascribed to an increase in hypolimnetic alkalinity following the artificial acidification of Lake 223. This is the first time that lake acidification has been linked to an increase in benthic alkalophilic diatoms associated with hypolimnetic alkalinity production following sulphate reduction. Sulphur in the anaerobic (black) sediment layers (0-1.5 cm) was isotopically light relative to the sulphur in the deeper layers. This was due to sulphur isotope fractionation resulting from the bacterial reduction of sulphate to hydrogen sulphide in the anaerobic portion of the water column. A jet black FeS-rich layer in the uppermost 1.5 cm of the lake's sediments was associated with an increase in the abundance of sulphate reducing bacteria (e.g. Desulfovibrio spp.).     

Combinations of Azadirachta indica and Cedrus deodara oil with piperonyl butoxide, MGK-264 and Embelia ribes against Lymnaea acuminata

The binary and tertiary combinations of plant-derived molluscicides Azadirachta indica and Cedrus deodara oil with synergists MGK-264, piperonyl butoxide (PB) and fruit powder of Embelia ribes were used against the Lymnaea acuminata. It was observed that the toxic effects of these mixtures were time- and dose-dependent. The binary and tertiary mixtures of plant-derived molluscicides with synergists were more toxic with respect to the single treatment of the plant-derived molluscicides. Maximum synergistic action in binary and tertiary combinations was found in A. indica + C. deodara oil and A. indica + PB + C. deodara in 1:7 and 1:5:7 ratio, respectively.     

Spatial and temporal variations in the trace elemental data over the northeastern United States

Time series of trace elemental concentrations (14 species) of atmospheric fine particles measured in the northeastern United States between 1988 and 1998 are analyzed for spatial and temporal variations. The influence of synoptic-scale systems to the transport and accumulation of pollutants can be investigated successfully if the short-term fluctuations (i.e. weather-induced variations) embedded in the time series of pollutant concentrations are separated from the original time series. The spatial short-term correlation coefficients for Al, Br, Fe, Se, and Zn permit good predictions of pollutant concentrations up to distances of about 350 km from a given monitor. The species correlation matrices for individual sites reveal that As, Br, Se, and Zn are highly correlated in New York State, while Fe, Mn, and V show also strong correlations, suggesting the commonality of source regions for these industrial and urban pollutants impacting New York.     

Assessing the impacts of partial mass depletion in DNAPL source zones I. Analytical modeling of source strength functions and plume response

Analytical solutions are developed for approximating the time-dependent contaminant discharge from DNAPL source zones undergoing dissolution and other decay processes. The source functions assume a power relationship between source mass and chemical discharge and can consider partial DNAPL source remediation (depletion) at any time after the initial DNAPL release. The source functions are used as a time-dependent boundary condition in an idealized chemical transport model to develop leading order approximations of the plume response to DNAPL source removal. The results suggest that partial DNAPL remediation does not tend to have a dramatic impact on the maximum extent of the plume if very low concentration values are used to define the plume boundaries. However, the solutions show that partial DNAPL removal from the source zone is likely to lead to large reductions in plume concentrations and mass, and it reduces the longevity of the plume. When the mass discharge from the source zone is linearly related to the DNAPL mass, it is shown that partial DNAPL depletion leads to linearly proportional reductions in the plume mass and concentrations.