bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidative degradation of 4‐nitrophenol in UV‐illuminated titania suspension
Authors: Lea Jimmy , Adesina Adesoji A 
Published: September 2002

AbstractAn internally‐irradiated annular photoreactor has been used to investigate the oxidative degradation of aqueous 4‐nitrophenol with titania as the photocatalyst. Reaction runs were performed over a 3‐h period and in practically all cases, complete degradation was possible within about 2 h. The kinetics was determined as a function of nitrophenol concentration, oxygen partial pressure, catalyst loading, pH, temperature and light intensity. The reaction was characterised by a relatively low activation energy of 7.83 kJ mol−1 although transport intrusions were negligible. Rate decreased almost exponentially with pH while a quadratic (maximum) behaviour with respect to both oxygen pressure and nitrophenol concentration is symptomatic of self‐inhibition possibly due to the formation of intermediates which competitively adsorb on similar sites to the reactants. Increased catalyst dosage also improved the reaction rate although the possible effects of light scattering and solution opacity caused a drop at loadings higher than about 1.20 g dm−3. Rate, however, has a linear dependency on light intensity, suggesting that hole–electron recombination processes were negligible at the conditions investigated.© 2001 Society of Chemical Industry
Comparison of filter media, plant communities and microbiology within constructed wetlands treating wastewater containing heavy metals
Authors: Scholz Miklas , Xu Jing , Dodson Hilary I 
Published: September 2002

AbstractThe aim of this study was to investigate the treatment efficiency of passive vertical‐flow wetland filters containing Phragmites australis and/or Typha latifolia and granular media of different adsorption capacities. A cost–benefit analysis was performed on the characteristics of constructed wetlands. Cheap gravel and sand as well as expensive granular activated carbon, charcoal and Filtralite (light expanded clay) were used as filter media. Different concentrations of lead and copper sulfate were added to polluted urban beck inflow water in order to simulate pre‐treated mine wastewater, landfill leachate or highway runoff. The relationships between growth media, microbial and plant communities as well as the reduction of lead, copper, five‐day biochemical oxygen demand (BOD) in particular, and potentially pathogenic bacteria were investigated. A breakthrough of copper within the first 9 weeks was only recorded for filters containing media with limited adsorption capacities. The breakthrough was independent of the presence of plants. However, after maturation of the biomass, which dominated the schmutzdecke and litter zone, lead and copper concentrations were reduced by 97–99% and BOD by 41–60% in all wetlands. There appears to be no additional benefit in using macrophytes and expensive adsorption media in constructed wetlands to enhance metal reduction during the set‐up period of 5 months.© 2001 Society of Chemical Industry
Fly ash quality, past, present and future, and the effect of ash on the development of novel products
Authors: Hall Martin L , Livingston William R 
Published: September 2002

AbstractA number of the more important environmental impacts of the operation of large coal‐fired power plants are associated with the very large quantities of solid materials resulting from these processes. These are, principally: coal ash residues, and solid residues of flue gas desulfurisation processes. By far the greater proportion of these materials, generally around 80% of the total solid discards from the electricity supply industry, comprise fly ash from the particulate collection equipment and bottom ash from the hoppers under the economisers and air preheaters of large pulverised coal boilers. The utilisation and disposal of the fly ash residues has been the subject of a great deal of development activity over many decades. In the main, the emphasis has been on the increased use of fly ash materials in high volumes, as constituents of cements and mortars, or for the manufacture of concrete and aggregate materials. The unsold ashes are used for land reclamation and for beneficial landfill, wherever possible. In recent years, there has been increasing interest in the processing of boiler fly ashes to improve ash quality and consistency, and in the manufacture of high‐value secondary products. The utilisation of power station fly ashes depends on their physical and chemical properties, and there have been a number of recent developments in power plant design and operation, which have resulted in significant changes in the characteristics of fly ashes, eg the progressive introduction of NOx emission control technologies and in‐furnace NOx reduction technologies. The increasing interest in the co‐firing of non‐conventional fuels such as petroleum coke and biomass/waste materials has resulted in the production of mixed and more complex materials. The paper will present a review of the major developments, which can affect coal fly ash quality and discuss the impact of these issues on the utilisation of fly ashes as feed materials for the manufacture of high‐value secondary products.© 2002 Society of Chemical Industry
Glass fibres from waste: production of continuous glass fibres from waste and their application in reinforced plastic material
Authors: Hreglich Sandro , Profilo Bruno , Vallotto Marta , Cioffi Flavio 
Published: September 2002

AbstractGlass fibres are well‐known reinforcing agents for different kinds of materials. For example, plastics, polyesters and epoxy resins can be reinforced using glass fibres originally developed for electrical applications; the resistance of bituminous materials is increased with the addition of chemically resistant glass fibres, and alkali resistant fibres are used in reinforced concrete. The price of conventional glass fibres is high because of the cost of the raw materials and of the high energy cost involved in the melting process. Therefore, a process which would allow the substitution of the natural raw materials with secondary products such as certain inorganic industrial wastes which have a lower melting temperature, would be of interest because it could increase the saving of energy and natural resources. Moreover, the disposal of industrial wastes in landfill would be reduced.© 2002 Society of Chemical Industry
Metallic ion removal from aqueous solutions by fly ashes: multicomponent studies
Authors: Rio Sébastien , Delebarre Arnaud , Héquet Valérie , Cloirec Pierre Le , Blondin Jacques 
Published: September 2002

AbstractFly ashes from two fluidised bed power plants were tested to remove Pb2+, Cu2+, Cr(III), Ni2+, Zn2+ and Cr(VI) from aqueous solutions. Experimental design methodology was used to study the removal and the leaching as a function of (i) the water pollutant content, (ii) the metal concentration in water, (iii) the pH of the solution and (iv) the addition of lime to fly ashes. The results show that the percentage of adsorbed ions was greater when they were in contact with silico‐aluminous fly ashes than sulfo‐calcic fly ashes, except in the case of the ion Ni2+. The removal of metallic ions increases with increasing pH. A comparison of the adsorption capacity with similar tests carried out with activated carbon or low‐cost sorbents shows that adsorption onto fly ash is an interesting alternative.© 2002 Society of Chemical Industry
Long term mechanical strength behaviour in fly ash/Portland cement mortars prepared using processed ashes
Authors: Payá J , Borrachero M V , Monzó J , Peris‐Mora E , Bonilla M 
Published: September 2002

AbstractIt is well‐known that some treatments of fly ash may improve its reactivity and consequently the strength of mortars containing these processed ashes. In this paper the effects of treatments on fly ashes are compared: sieving, grinding, and magnetic extractions from aqueous suspensions. The influence of these processed ashes on compressive strength development of mortars containing processed fly ashes for long curing periods was studied. The gain or loss of compressive strength with respect to mortar that contains original ash has been calculated; most mortars present positive values, although for the longest curing times (more than 90 weeks), these values tend towards unity except for ground fly ash mortars. The grinding treatment has proved to be an effective treatment for improving the compressive strength of mortars containing fly ashes over long curing times. The high activity index values versus curing time for mortars containing 60% replacement demonstrate that for high fly ash volume mortars the processing of original ash has very favourable effect on the strength. Moreover, the morphology of the cement/fly ash hydrated matrix of old mortars was analysed by SEM and also thermogravimetric methods have been applied for evaluation of lime content and hydrates. For old mortars containing a high volume of ground fly ashes (60% replacement) residual lime due to hydration of Portland cement has not been detected, suggesting that the optimum replacement in order to produce the maximum quantity of pozzolanic reaction products would be lower than 60%.© 2002 Society of Chemical Industry
Thermal analysis of fly ashes sourced from European non‐blended coals
Authors: Stanton Kenneth T , Towler Mark R , Mooney Patrick , Hill Robert G , Querol Xavier 
Published: September 2002

AbstractFly ashes exist as a mixture of major amorphous phases and minor crystalline phases. For commercial applications, such as in concretes and for the production of zeolites, it would be desirable to be able to predict the reactivity of fly ashes. The amorphous phase dominates degradation behaviour, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass make the bond breakage easier. Despite the large quantities of fly ash produced annually by coal‐burning power plants, there have been very few studies investigating the microstructure and composition of the amorphous component. In particular, there has been little research undertaken in measuring the glass transition temperature (Tg), which can be directly correlated to the chemical reactivity of the glass phase. Thirteen European fly ashes were used for the present study. Differential scanning calorimetry (DSC) was employed to determine the presence of transition temperatures and any other thermal events (exotherms or endotherms) in the glassy phase of the fly ashes. Several different but distinct behaviours were evident in the DSC traces with Tg values visible for six of the ashes. The results suggest that thermal analysis has potential as a technique for fly ash characterisation.© 2002 Society of Chemical Industry
Encouraging prospects for recycling incinerated sewage sludge ash (ISSA) into clay‐based building products
Authors: Anderson Michael 
Published: September 2002

AbstractStaffordshire University has recently completed a laboratory investigation into the potential utilisation of incinerated sewage sludge ash (ISSA) which has now become a serious disposal problem in the United Kingdom. This study involved a physical, chemical and ceramic evaluation of a source of ISSA produced at a newly commissioned sewage sludge incinerator sited near Manchester, initially to establish its level of variability on a day‐to‐day basis. Subsequently, feedstocks from two commercial brick factories both using raw materials of contrasting ceramic properties were obtained to examine the effect of their partial replacement by this source of ISSA. This work programme involved fabricating and firing experimental test‐samples (containing 5% dry w/w ISSA substitution) by the plastic‐extrusion forming method which is employed at both brickworks to manufacture their respective products. Standard ceramic testing procedures were subsequently carried out on the products containing ISSA and compared with those of the normal brick products fabricated in parallel. From the positive results obtained it is believed that the introduction of this source of ISSA as a new raw material for use in brick manufacture potentially offers attractive prospects. Moreover, its application in this identified role would provide an innovative alternative to its current landfill disposal, while also offering a direct contribution towards maximising the conservation of traditional brickmaking raw material reserves.© 2002 Society of Chemical Industry
Zeolite synthesis from a high Si–Al fly ash from East China
Authors: Zeng R , Umaña J C , Querol X , Lopez‐Soler A , Plana F , Zhuang X 
Published: September 2002

AbstractA high Al–Si Chinese fly ash from Dou He power plant (Tangshan city, Hebei Province, Eastern China) was selected as starting material of the zeolitisation process. Zeolitic material was obtained by conventional alkaline activation using NaOH and KOH solutions. The process of synthesis was optimised by applying a wide range of reaction temperature, time and activation reagent concentrations. A high solution/fly ash ratio was used in order to dissolve highly resistant Al–Si phases such as mullite. High yields were obtained with both KOH and NaOH solutions. Final products reached a cation exchange capacity (CEC) of up to 2.3 meq g−1. Major zeolites obtained with a high CEC were: NaP1, KM and F‐linde zeolite. The low contents of major impurities of this fly ash enhance the potential application for the synthesis of zeolites for waste‐water treatment.© 2002 Society of Chemical Industry
Effect of precursors on surface and catalytic properties of Fe/TiO2 catalysts
Authors: Pecchi Gina , Reyes P , López T , Gómez R , Moreno A , Fierro J L G 
Published: September 2002

AbstractTitania‐supported iron (5 wt%) catalysts were prepared by a sol–gel method using different gelation pH and metal precursors (Fe(II) and Fe(III)). Characterization data of calcined catalysts revealed that, irrespective of the nature of the metal precursor, iron is present in all cases as ferric oxide. However, the crystalline phase exhibited by titania does depend on the metal precursor used. The catalytic activity of the catalysts, tested in the combustion of methane at atmospheric pressure, is not related to the dispersion of iron oxide. Thus, Fe3+ ions may be obtained in two extreme situations; one highly dispersed in which Fe3+ ions are placed in the titania network and another in which large Fe2O3 crystals are located on the surface of the catalyst. The former exhibits the best performance in the combustion of methane.© 2002 Society of Chemical Industry
Preparation of dry powder dispersions for non‐viral gene delivery by freeze‐drying and spray‐drying
Authors: Seville P. C. , Kellaway I. W. , Birchall J. C. 
Published: September 2002

AbstractBackgroundDry powder dispersion devices offer potential for delivering therapeutic macromolecules to the pulmonary epithelia. Previously, freeze‐drying (lyophilisation) has been the accepted method for preparing dried formulations of proteins and non‐viral gene vectors despite the respirability of such powders being inadequate without further processing. In this study we compare the utility of freeze‐drying and spray‐drying, a one‐step process for producing dry and respirable powders, as methods for preparing non‐viral respiratory gene delivery systems.MethodsLipid:polycation:pDNA (LPD) vectors comprising 1,2‐dioleoyl‐3‐trimethylammoniumpropane (DOTAP), protamine sulphate and pEGFP‐N1 in 3% lactose solution were either snap‐frozen and lyophilised or spray‐dried. Lyophilised powder was used as recovered or following coarse grinding. Structural integrity of dehydrated pDNA was assessed by agarose gel electrophoresis and powder particle size determined by laser diffraction. The apparent structure of the systems was visualised by scanning and transmission electron microscopy with the biological functionality quantified in vitro (A549 human lung epithelial cell line) by Green Fluorescent Protein (GFP) associated fluorescence.ResultsLyophilisation produced large, irregularly shaped particles prior to (mean diameter ∼21 µm) and following (mean diameter ∼18 µm) coarse grinding. Spray‐drying produced uniformly shaped spherical particles (mean diameter ∼4 µm). All dehydrated formulations mediated reporter gene expression in A549 cells with the spray‐dried formulation generally proving superior even when compared with freshly prepared LPD complexes. Biological functionality of the LPD dry powders was not adversely affected following 3 months storage.ConclusionsSpray‐drying has utility for producing stable, efficient and potentially respirable non‐viral dry powder systems for respiratory gene delivery. Copyright © 2002 John Wiley & Sons, Ltd.
Human cell lines engineered for tetracycline‐regulated expression of tumor suppressor candidate genes from a frequently affected chromosomal region, 3p21
Authors: Protopopov Alexei I. , Li Jinfeng , Winberg Gösta , Gizatullin Rinat Z. , Kashuba Vladimir I. , Klein George , Zabarovsky Eugene R. 
Published: September 2002

AbstractBackgroundWe modified a tetracycline‐regulated system that can control the activity of individual genes quantitatively and reversibly in transgenic mammals. Despite these advances, there remained one problem in the intensive use of the tet‐system: the limited range of acceptor cell lines, expressing a tetracycline‐controlled transcriptional activator (tTA). This study describes in detail new vectors and a unifying strategy to generate tTA‐expressing cell lines.MethodTwo retroviral vectors pLNCtTA‐hCMV and pLNCtTA‐EF1α coding for the tTA were used to engineer cell lines to constitutively express tTA. New expression vectors pETE‐Hyg and pETE‐Bsd were also created that replicate in episomal form in human cells and facilitate tetracycline‐regulated expression of targeted genes.ResultsThe primate‐tropic retroviruses efficiently delivered the regulatory tTA gene into 12 selected human cancer cell lines. Two candidate tumor suppressor genes from the human 3p21–p22 region MAPKAPK3 (3pK) and MLH1 were cloned into the episomal vector and transfected into engineered A9 and KRC/Y cells. The transfectants were subcutaneously grown in SCID mice, and the expression of the transgene was successfully controlled in vivo by tetracycline administered ad libitum in drinking water. The experiments demonstrated that both transgenes did not antagonize the tumorous growth of these cells.ConclusionsNew retroviral and episomal vectors appear particularly suited for tight regulation of genes that cause suppression of cell growth. The generated cell lines can be used in various applications to study the effect of an inducible transgene in human cancer cells. Copyright © 2002 John Wiley & Sons, Ltd.
The depoliticization of Karl Lashley: A response to Dewsbury
Authors: Weidman Nadine 
Published: September 2002

AbstractIn this response to Donald Dewsbury's article, I address Dewsbury's criticisms of my interpretation of Karl Lashley by, first, disputing Dewsbury's characterization of my historiographic stance. I then go on to address Dewsbury's specific points, particularly regarding Lashley's racism and hereditarianism, which I argue are central to an understanding of the context of his science. I conclude by criticizing Dewsbury's proposed personality theory of Lashley on the grounds that it depoliticizes Lashley by psychologizing him. © 2002 Wiley Periodicals, Inc.
Freud's “bad conscience”: The case of Nietzsche's Genealogy
Authors: Greer Scott 
Published: September 2002

AbstractThis article develops the argument that Friedrich Nietzsche influenced several aspects of Freud's later writings by illustrating, in particular, the impact of Nietzsche's On the Genealogy of Morals on Freud's Civilization and its Discontents. The theoretical and conceptual schemes represented in Freud's Discontents are found to bear a remarkable similarity to Nietzsche's Genealogy on a number of highly specific points. It is suggested that “das Es,” “Uber‐ich,” and “bad conscience,” concepts central to Freud's moral theory of mind, are at least partly derived from Nietzsche. Moreover, Freud's phylogenetic theory of guilt is based upon premises found in Nietzsche, as are specific details relating to ideas on human prehistory and the ancestral family. Based on this evidence, a re‐examination of the moral and social dimensions of Freud's “structural” model may be in order. © 2002 Wiley Periodicals, Inc.
Commentary on ‘The economics of landmine clearance: case study of Cambodia’
Authors: Paterson Ted 
Published: September 2002

AbstractA recent cost‐benefit analysis of landmine clearance in Cambodia (Harris, JID 12(2), 2000) reported a net present value (NPV) of minus $3,434 million, and concluded landmine clearance using existing technologies is not economically justified for Cambodia. Professor Harris suggested higher returns would accrue to investments in de‐mining technology, while aid funds for landmine clearance should be reallocated to meet other development objectives. However, the methodology used massively overstates the present value of de‐mining costs while the estimated benefits are far too low. More fundamentally, the specification of the model makes it suitable only for an ‘all‐or‐nothing’ decision whether to rid Cambodia entirely of landmine contamination, and does not allow the analysis of targeted clearance of priority land. With appropriate adjustments, the economics of landmine clearance in Cambodia are not bleak, and may well yield positive rates of return in NPV terms. Copyright © 2001 John Wiley & Sons, Ltd.
Testing alternative measures of microenterprise profits and net worth
Authors: Daniels Lisa 
Published: September 2002

AbstractUsing data from 448 microenterprises in Zimbabwe, this paper examines five alternative measures of profits and five alternative measures of net worth. The results show that the single‐question proxies are too difficult for proprietors to answer, whereas the most complex profit measures generate many negative estimates. The best measure of profits, based on three questions, could be answered by all proprietors and it avoids recall problems associated with sales and expenses. Among the net worth proxies, all of the measures are positively correlated. Nonetheless, the proxy based on fixed assets, accounts receivable, debt, and inventory, showed the highest correlation with the full measure of net worth. Copyright © 2001 John Wiley & Sons, Ltd.
Structural requirements for stable binding of technetium‐99m to derivatives of triglycine
Authors: Vanbilloen Hubert P. , Busson Roger , Verbruggen Alfons M. 
Published: September 2002

AbstractTo study the importance of the thiol function of mercaptoacetyltriglycine (MAG3) for complexing technetium, we investigated a number of derivatives wherein the thiol function of MAG3, is replaced by other metal binding groups such as 3‐nitropropionyl, thiophene‐2‐carbonyl, pyrrole‐2‐carbonyl, acetoacetyl, hydroxyacetyl, picolyl or aminoacetyl. These groups have the potential to form a bond with Tc via a free electron pair or the loss of a proton.3‐Nitropropionyltriglycine, thiophene‐2‐carbonyltriglycine and pyrrole‐2‐carbonyl‐triglycine were not able to form a single complex with 99mTc. Under the experimental conditions, acetoacetyltriglycine forms a rather unstable 99mTc‐complex. On the other hand, the acetoacetyl group possesses sufficient complexing capacity to serve as the fourth coordination site of a tetraligand with a strongly technetium binding thiol and two amides. Hydroxyacetyltriglycine and derivatives of MAG3 in which the thiol group is substituted by an aromatic amine, as in picolyltriglycine, or an aliphatic amine, as in tetraglycine and other tetrapeptides, form complexes with technetium‐99m which are stable for several hours. Copyright © 2001 John Wiley & Sons, Ltd.