bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic Nanoparticles: Synthesis, Protection, Functionalization, and Application
Authors: Lu An‐Hui , Salabas E. L. , Schüth Ferdi 
Published: February 2007

AbstractThis review focuses on the synthesis, protection, functionalization, and application of magnetic nanoparticles, as well as the magnetic properties of nanostructured systems. Substantial progress in the size and shape control of magnetic nanoparticles has been made by developing methods such as co‐precipitation, thermal decomposition and/or reduction, micelle synthesis, and hydrothermal synthesis. A major challenge still is protection against corrosion, and therefore suitable protection strategies will be emphasized, for example, surfactant/polymer coating, silica coating and carbon coating of magnetic nanoparticles or embedding them in a matrix/support. Properly protected magnetic nanoparticles can be used as building blocks for the fabrication of various functional systems, and their application in catalysis and biotechnology will be briefly reviewed. Finally, some future trends and perspectives in these research areas will be outlined.
Effect of diacid stabilizers on kinetics of hydrolytic polymerization of ϵ‐caprolactam in industrial reactors
Authors: Agrawal Ashwini K. , Gupta Deepak K. , Devika Kotilingam , Manabe Tomonobu 
Published: February 2007

AbstractThe rate constants in hydrolytic polymerization of ε‐caprolactam are dependent on the concentration of carboxylic acid groups in the reaction medium. Therefore, the use of diacid stabilizers for regulating molecular weight are likely to have favorable effect on the kinetics of polymerization compared to monoacid stabilizers, which are traditionally used in such polymerizations. To understand the kinetics of polymerization in the presence of diacid stabilizer compared to monoacid stabilizer, mathematical kinetic models were developed using the end group approach. These models were used to quantify the effect of both stabilizers on nylon‐6 synthesis in a closed isothermal batch reactor at different temperatures in the range of 245–265°C. The kinetic model for the diacid‐stabilized system was then extended to an industrial VK tube reactor using the process model developed earlier for the monoacid stabilized system. Both the mathematical modeling and experimental results showed that the presence of diacid stabilizer could significantly enhance the overall kinetics of the reaction compared to the monoacid stabilized system and in turn, resulted in reduction of the polymerization time by about 20–25%. The study suggests that diacid stabilizers may be used preferably over monoacid stabilizers in synthesis of nylon‐6 to reduce the cost of polymerization. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Thermodynamic studies related to emulsion polymerization
Authors: Balashova Ida M. , Galdámez J. Román , Danner Ronald P. , Duda J. Larry 
Published: February 2007

AbstractLiquid–liquid and vapor–liquid phase equilibria for the binary, ternary, and quaternary systems of vinyl acetate, surfactant, water, and poly(vinyl acetate) (PVAc) were obtained using liquid–liquid equilibria, inverse gas chromatography, and the headspace methods. The Flory–Huggins interaction parameters for the different species in the emulsion polymerization of PVAc latices are reported. These parameters could not be used to predict the phase equilibria because of their strong dependence on concentration. The UNIFAC‐vdW‐FV model was applied to predict the vapor–liquid equilibria in the binary and ternary systems containing vinyl acetate, 4‐nonylphenol polyethoxilate surfactant, and PVAc. The predicted results compare favorably with the experimental data for all systems. Diffusion coefficients were also measured for the solvents in the PVAc. Analysis confirmed that the diffusion in the latex particles was so fast compared to the reaction that the assumption of uniform monomer composition through the particles was valid. On the other hand, the results indicate that the complex thermodynamic interactions will lead to changes with time in the monomer concentration in the reacting polymer phase. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Conserving the freshwater pearl mussel (Margaritifera margaritifera L.) in the British Isles and Continental europe
Authors: Young Mark R. 
Published: February 2007

Abstract1. This paper reviews the status of the freshwater pearl mussel (Margaritifera margaritifera L.) in the British Isles and Continental Europe.2. The mussel has continued to decline in recent decades throughout the European range, apparently caused mainly by pollution (especially by organic enrichment) and, in the British Isles, by a combination of this and overfishing for pearls.3. Of particular concern is the almost complete absence of juveniles in most populations, with these occurring in numbers only in a very few rivers in remote locations.4. M. margaritifera is now completely protected in most European countries and in Britain the government has recently made it an offence to kill or harm the mussel. However, it will still be permitted to take the mussel, examine it carefully for pearls, and then to return it unharmed to the river. This may prove difficult to enforce and it is concluded that it will be ineffective and that complete protection may still be needed.5. There is no current monitoring programme for M. margaritifera anywhere in its range and without continuing evidence on its status and further research on the habitat requirements of the juveniles, it is difficult to be optimistic about its survival.
The brackish ponds at Killingholme, Humberside, UK
Authors: Bamber R. N. , Batten S. D. , Bridgwater N. D. 
Published: February 2007

Abstract1. The National Power site at Killingholme, on the Humber Estuary, contains three brackish ponds at the northeast corner, adjacent to Killingholme Haven. The ecology and conservation importance of these ponds were surveyed as part of a Nature Conservancy Council lagoon research programme in 1986 and by National Power staff in 1990 and 1991.2. The north and west ponds were found to be saline, and both supported the nationally rare polychaete worm Alkmaria romijni. The east pond was fragmenting, owing to the incursion of the reed Phragmites australis, and predominantly freshwater.3. A total of nine characteristic lagoonal species was present in the system.4. In 1990 the saline ponds had been allowed to dry out extensively, which was detrimental to the lagoonal species.5. The surveys concluded that the system of ponds is of national importance for conservation on account of its invertebrate community, particularly with the diversity of lagoonal habitat it offers. Optimum management of the system for conservation is discussed.
Conservation of freshwater fish in the British Isles: the status of fish in national nature reserves
Authors: Lyle Alex A. , Maitland Peter S. 
Published: February 2007

Abstract1. To consider fully the conservation management of freshwater fish, it was important to know which fish were already in the protected environment of National Nature Reserves (NNRs) — the principal sites for nature conservation in Great Britain. For this reason, 235 NNRs declared by the Nature Conservancy Council (NCC) were surveyed for freshwater fish between 1987 and 1990 by questionnaires to the wardens, by compiling data from other sources, and, where necessary, by field sampling. The presence of fresh waters (as lakes, ponds, rivers and streams) was also recorded. The survey was organized to follow the country and regional structure by which nature conservation was administered by the NCC so that the results could be considered accordingly.2. Seventy five percent of NNRs contain fresh waters and, of these, just over 20% have no fish. Of the 51 fish species available 37 (73%) were recorded in NNRs. NCC regions with most fish species are: SW Scotland, West Midlands and East Anglia, but NW Scotland has the highest total of species occurrences in NNRs. In terms of both the numbers of species and their frequency of occurrence, NW and NE England are notably the lowest. The most common fish in NNRs are Eels, Brown Trout and Three‐spined Sticklebacks.3. The results for species and for sites (NNRs) are discussed from the viewpoint of fish conservation. The majority of fish in NNRs are those most common in Great Britain. Two of the species recorded (Powan and Smelt) are currently important for conservation, but several of those most threatened do not occur in NNRs. A number of NNRs have diverse fish communities, but only six have significant fish conservation value, of which Loch Lomond NNR is outstanding.4. There is considerable scope through NNR management to improve fish conservation and it is suggested that the acquisition of new reserves for threatened species should be considered.
Channelling scientific information for the conservation and management of rivers
Authors: Boon P. J. 
Published: February 2007

Abstract1. This paper discusses the characteristics of scientific information used in river conservation and management.2. Information should be appropriately focussed, achieving a balance between the ideal and the achievable, recognizing the functioning of river basins and not merely river channels.3. Technical data need to be presented in a way that is readily understood by decision‐makers — simply, but not simplistically. This is discussed using examples such as river corridor mapping and the application of numerical indices of water quality and conservation value.4. Ideally, river management policy and practice requires a scientific input that is both unequivocal and authoritative. Frequently, however, disagreement over its interpretation delays information transfer.5. The results of applied studies in freshwater science are not always as accessible as they should be to river managers. Once acquired there must be a genuine willingness by planners to incorporate the results of ecological research into project design, a process often hindered by complex bureaucratic structures. It is thus argued that operational flexibility in river management schemes is desirable, and post‐project appraisal essential.
A botanical classification of standing waters in Britain: Applications for conservation and monitoring
Authors: Palmer M. A. , Bell S. L. , Butterfield I. 
Published: February 2007

Abstract1. A classification is described based on an indicator species analysis of the vegetation of 1124 fresh and brackish standing water sites in Great Britain.2. Ten Site Types are recognizable by their assemblages of plants, and these groupings are related to the alkalinity, pH and conductivity of the water. One Type consists of extremely acid water bodies on peat. There are two other nutrient‐poor Types, distinguishable from each other largely by size and substrate, as well as by vegetation. These sites lie mostly in the north and west of Britain. There are four distinct Site Types with nutrient‐rich water, one characteristic of Scotland, the rest more typical of the lowlands of southern and eastern Britain. A further Site Type is regarded as mesotrophic and is found mainly in northern England and Scotland. Of the remaining two Site Types, one shows an unusual combination of base‐poor and base‐rich characteristics and the other comprises brackish sites in Scotland.3. The use of the classification for producing Trophic Ranking Scores, both for individual species and for sites, and the application of these scores for monitoring the nutrient status of fresh waters are explained.4. The application of the classification to the selection of sites important for nature conservation is discussed, with special reference to north west Scotland.5. This classification is compared with other classifications of aquatic vegetation in Great Britain.
Effects of large woody debris removal on physical characteristics of a sand‐bed river
Authors: Douglas Shields F. , Smith Roger H. 
Published: February 2007

Abstract1. Removal of large woody debris (LWD) is one of the most widely practised stream alterations, particularly in sand‐bed rivers of the south‐eastern USA. Selective removal of LWD has been proposed as an alternative to orthodox non‐selective clearing in order to conserve ecological resources, but methods for comparing hydraulic and environmental effects of selective and non‐selective removal have not been developed. Conservation of stream habitats requires quantification of LWD removal impacts on physical habitat.2. Physical characteristics of straightened, sand‐bed reaches of the South Fork Obion River in western Tennessee, USA that were rich in LWD were compared with those in similar reaches where debris had recently been removed using selective removal guidelines.3. The mean volume of LWD per unit water volume was 0.0545 in the uncleared reaches, but nearly 60% lower (0.0225) in the cleared reach.4. A simple technique for predicting hydraulic roughness in channels with varying amounts of LWD was developed. Hydraulic roughness, as measured by the Darcy‐Weisbach friction factor, was about 400% greater in uncleared reaches at base flow but declined to a level about 35% greater than for the cleared reaches at higher flows. Predicted friction factors were within 35% of measured friction factors at higher flows.5. Physical habitat diversity in this channelized sand‐bed stream was strongly related to the density of LWD. Flow conditions in the uncleared reaches were more heterogeneous than in the cleared reach, especially at low flow. At low flow, uncleared reaches tended to be shallower, have lower velocities, slightly finer bed material, and more heterogeneous conditions overall. Shannon indices based on depth and velocity were an average of 48% higher in uncleared reaches.6. Bed sediments underneath and immediately adjacent to LWD formations were finer and contained more organic matter than sediments distant from LWD. However, when all bed samples were considered, organic content was positively correlated with median grain size.
Conservation of freshwater fish in the British Isles: Proposals for management
Authors: Maitland Peter S. , Lyle Alex A. 
Published: February 2007

Abstract1. Recent checklists of the freshwater fish of the British Isles have included 42 native and 13 introduced species. Of the former, however, two are extinct now and eight are threatened in various ways. In addition there are several important stocks of common native species under threat.2. Protection for British fish exists mainly through legislation and protected sites of various designations. The legislation is inadequate in some respects and very few of the protected sites were actually established for their fish interest. Nevertheless, in Great Britain, 37 species of fish occur in National Nature Reserves. The overall status of fish in Sites of Special Scientific Interest is unknown.3. The main conservation options for managing freshwater fish resources are habitat restoration, stock transfer to new sites, captive breeding and cryopreservation. The first two of these are regarded as the most useful for the long‐term conservation of threatened species. Improved legislation would also help, especially in relation to preventing the import and transfer of potentially harmful species.4. As well as the implementation of conservation management programmes for rare fish, research and monitoring studies are also needed in order to aid management and maintain a watch on populations of important species. In addition, national fish databases and registers of important stocks are an important background for overall fish conservation and management.
The impact of land‐claim on macrobenthos, fish and shorebirds on the forth estuary, eastern Scotland
Authors: McLusky Donald S. , Bryant David M. , Elliott Michael 
Published: February 2007

Abstract1. The impact of land‐claim on the intertidal areas of the Forth estuary, eastern Scotland is described. It is shown that in recent times almost 50% of the intertidal area has been destroyed for a variety of purposes, including agriculture, harbours and industrial development.2. The loss of infaunal invertebrate biomass and production from the intertidal habitat has been calculated for each part of the estuary, and by summation for the whole estuary. The loss is discussed in relation to the total biomass and production, both intertidally and subtidally, of the estuary. It is shown that proportionately more biomass and production may have been lost than area.3. The impact of land‐claim on estuarine fish is calculated. Land‐claim has removed 24% of the natural fish habitats in the Forth estuary, and thereby removed 40% of their food supply.4. The impact of habitat loss on birds was observed for one area where observations continued throughout a period of land‐claim. For individual bird species at Torry Bay, land‐claim had consequences ranging from neutral to substantially negative. Significant declines were found for overwintering populations of dunlin and bar‐tailed godwit. Comparisons of pre‐ and post‐land‐claim bird feeding usage of this area, showed that the impact of land‐claim on local bird populations differed between species. The large scale loss of habitat on the Forth seems likely to have reduced the size of some shorebird populations which overwinter on the estuary.5. It is concluded that when considering the impact of land‐claim on estuaries that, as found in some previous studies, a simple consideration of area lost may be inadequate to describe the effects of land‐claim, and the consequences for animals living within the estuary may differ considerably amongst themselves and from area to area.
A survey of pond loss in Essex, South‐east England
Authors: Heath D. J. , Whitehead A. 
Published: February 2007

Abstract1. Sample areas of the county were used to estimate pond loss. An extensive survey used only maps while a smaller, intensive survey combined maps with a field study. In total, 283.43 km2 were surveyed, approximately 7% of the total area.2. Fifty‐five per cent of the ponds present in 1870 had disappeared by 1960 with the greatest loss occurring between 1920 and 1960.3. Loss of ponds in agricultural locations contributed most to this because of their high initial number and their high rates of loss. Percentage losses of large and small ponds were greater than for medium‐sized ponds.4. A field survey showed that a further 23% of a random sample of ponds shown on maps of 1960 could not be found in 1989. Overall loss rates for the period 1870–1989 are estimated to be 68.6% for the extensive area and 54.8% for the intensive area.
Management of the exploitation of the lugworm Arenicola marina and the ragworm Nereis virens (Polychaeta) in conservation areas
Authors: Olive P. J. W. 
Published: February 2007

Abstract

In Europe, bait supply to anglers from the natural environment involves: (i) bait collection by anglers for own use, (ii) local semi‐professional bait digging and (iii) professional bait digging contracted to distributors.
The management of bait digging activity is particularly acute where there is a conflict with conservation interests.
Two case studies are presented describing the population dynamics of: I Arenicola marina in the Lindisfarne nature reserve, and II Nereis virens in the Menai Strait; both in conservation areas.
Case I. Populations of A marina are subject to marked annual cycles in number and fresh weight. This case illustrates the response of the population to substantial overexploitation leading to a population crash. With the introduction of restrictive legislation the population was re‐established by recruitment of adults from neighbouring unexploited populations.
Case II illustrates the dynamics of a N. virens population dominated by large old individuals; it does not represent a sustainable resource in contrast with populations of the same species in other locations.
The management of the exploitation of bait populations in conservation areas is discussed in relation to world patterns of utilization and supply.
PCBs and organochlorine pesticide residues in otter (Lutra lutra) spraints from Welsh catchments and their significance to otter conservation strategies
Authors: Mason C. F. , Macdonald S. M. 
Published: February 2007

Abstract

A survey is presented of PCB and organochlorine pesticide concentrations in otter (Lutra lutra) spraints (faeces) from 18 catchments/sub‐catchments in Wales and adjacent English counties.
There were wide differences in concentrations of lindane, dieldrin, DDE and PCBs between catchments and at sites within catchments. Only PCBs were considered likely to be of significance in influencing otter populations. Mean PCB concentrations (but not those of dieldrin and DDE) were inversely related to otter population performance (as measured by both catchment distribution and sprainting intensity) between catchments.
It is suggested that PCB contamination is exerting a negative impact on otter populations in four catchments, while there is concern over four others. A study of food chain contamination should be an essential component of otter conservation strategies at both the national and local level.
New Zealand's Resource Management Act and fresh water
Authors: Scott D. 
Published: February 2007

Abstract

This paper describes New Zealand's Resource Management Act in relation to freshwater management and conservation.
The development of the Act is described with reference to the consolidation and integration of earlier legislation. The central concept of sustainable management is more limited than the related concept of sustainable development, and places constraints on activities which have environmental impacts.
The specific provisions relating to fresh water are noted, and the resource consents required for taking water, damming or diverting watercourses, and discharging into water, or onto land where the discharge may reach water, are described. The relation of riparian management to the requirement for protection of fish habitat is noted, and water conservation orders are described. Attention is given to the likely implications for managers.
An attempt is made to anticipate difficulties that may arise in implementing the Act; in particular, the possible balancing between socio‐economic and ecological considerations. The specific features of the freshwater environment are considered from the viewpoint of management, and the problems involved in tradeability are noted. Attention is drawn to the scope of the Act in the attempted integration of most, but not all, environmental considerations, and a final evaluation suggests that economic growth is likely to present a substantial challenge to the purpose of the Act.
Interaction between seals and marine fish‐farms in Tasmania, and management of the problem
Authors: Pemberton D. , Shaughnessy P. D. 
Published: February 2007

Abstract

Seals that attacked fish on 15 marine fish‐farms in south‐eastern Tasmania were large subadult and adult male Australian fur seals Arctocephalus pusillus doriferus. From July to November 1988 there were 235 attacks on fish‐farms where Atlantic salmon Salmo salar and rainbow trout S. gairdneri were held in pens. Single animals usually attacked pens at night, irrespective of the size and species of fish in the pens. The seals damaged both pens and fish, and sometimes fish escaped as a result of the attacks.
The vulnerability of fish‐farms was influenced by their proximity to seal haul‐out sites. Proximity to fishing ports and size of the fish‐farm had little influence.
The use of shooting as a protection method was inefficient and ineffective because seals usually entered fish‐farms at night and showed no fear of shooters. There were many attacks in the presence of underwater acoustic seal scarers. Deterrents such as pursuit with boats, lights, seal crackers and emetics helped reduce the number of seal attacks.
The only way totally to prevent seals from attacking fish‐farms is to exclude them from the vicinity of the fish pens with physical barriers that they cannot penetrate. These are currently in use, and include perimeter fences and protection nets made of steel mesh set around individual pens.