Comparative effects of cement,coal dust and fly‐ash on H. Abelmoschus

Three types of dusts, i.e. cement, coal and fly‐ash were applied daily at the rate of two grams per square metre per day to 15 days old plants for a period of one month. Visible foliar symptom, photosynthetic pigment content and dry weight were taken as parameters. Small chlorotic spots and marginal chlorosis appeared in leaves sprayed with cement and coal dust respectively. Cement dust was more toxic to chlorophylls than coal dust, while a slight increase was noted in case of fly‐ash. Carotenoids were relatively unaffected by dust pollution.     

Wet‐dry process of HCL removal from flue gas: experimental study on operating parameters

Wet‐dry process of hydrogen chloride removal from flue gas has been studied at pilot scale. Hot gas produced by methane burner, added with gaseous hydrogen chloride, is contacted by an aqueous suspension of calcium hydroxide in a cylindrical steel vessel 0.25 m I.D. and 4 m high.

The effects of feed ratio Ca(OH)₂/HCl, hydrogen chloride concentration in the inlet gas, operating temperature and residence time on the amount of hydrogen chloride removed have been exstensively investigated. The effect of inside wall fouling by Ca(OH)₂ has also been evaluated.

The experimental results show that the overall amount of hydrogen chloride removed increases when the feed ratio and the gas inlet concentration are increased and the operating temperature is decreased. However, the HCL removal does not seem affected by the residence time within the short interval investigated.     

By‐products formation in catalytic combustion of aromatic compounds over a pt‐based catalyst

By‐products formation in the catalytic combustion of different aromatic compounds has been experimentally investigated. A commercial Pt‐based catalyst, in the shape of a short monolith, has been employed. Toluene, styrene, o‐xylene and cumene have been tested at low concentrations for conversions in the range 5–50%. The results confirm the formation of benzene in the combustion of toluene and styrene, as previously observed by other researchers, but in a very small amount; testing cumene, significant amounts of acetone have been found in the outlet flow. Some hypothesis about the reaction mechanism are put forward.     

Forest exploitation in Cameroon (1884–1994): an oxymoron of top‐down and bottom‐up forest management policy approaches

Forest exploitation in Cameroon goes back to the pre‐colonial period when early ethnic settlers used the ‘law of status’ system to manage land and forests in the territory. With the arrival of colonial powers, beginning with the Germans in 1884, the law of status system was replaced by top‐down state‐centred management system. This top‐down management system was inherited by post‐colonial authorities and enforced until 1994 when a new forestry law was launched, based on bottom‐up management system. This paper reviews all these three systems. Communities are not benefiting from an actual bottom‐up management system. The author argues that the forests sector in Cameroon needs a new management paradigm.     

Inner city area in transition. Consequences of product‐oriented planning in Oslo

The article presents results from a research teamwork between an architect, an art historian and an ethnologist, analyzing an urban renewal process in an inner city area in Oslo: Gr?nland/Nedre T?yen. The project is a part of Research Programme on Norwegian Cities, initiated by Norwegian Research Council for Science and the Humanities. The officially initiated and controlled renewal process is analyzed from an ethnological point of view, as a cultural process. The author questions whether urban qualities can be taken care of in a product‐oriented process, with the goals and standards already set, and where the planning models are very simple, seen in relation to an old and complex multifunctional area. The “freezing” of a future situation by product‐oriented planning and implementation seems incompatible to the very nature of “natural” cultural processes, where the changes are generated and controlled by the members of the society themselves.     

Some characteristics of soil stabilization by “sealed” injection using microcement

Characteristic features of “sealed injection” for the microcement stabilization of the saturated soils between the Serebryanovorsk transportation and service tunnels in Moscow are examined. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 1, pp. 25–28, January–February, 2008.     

Effect of ethanol on the performance,emission and combustion characteristics of a compression ignition engine fuelled with vegetable oil–diesel blend

Experimental work had been carried out to analyse the effect of ethanol on the performance, emission and combustion characteristic of vegetable oil–diesel blend (50% vol. rapeseed oil and 50% vol. diesel fuel). The vegetable oil–diesel–ethanol blended fuels were prepared by using microemulsification technique and the main properties were measured. The results showed that, with the increase in ethanol volume fraction in the blends, the viscosity and density were decreased and close to those of diesel fuel. The combustion started later; the peak cylinder pressure, peak heat release rate varied significantly under different operating conditions and the corresponding crank angles of the peak values were retarded. There were slightly higher brake-specific fuel consumptions. Smoke and nitrogen oxide emissions were observed to reduce, but carbon monoxide and hydrocarbon emissions were found slightly higher with the increase of ethanol volume fraction under all ranges of engine operating conditions.     

Women's self‐perception: an inter‐sector comparison of construction,legal and nursing professionals

The issue of gender in the construction industry has received considerable attention. However, most of the research has been from a male perspective and has considered how male perceptions of females act as an impediment to women's career progression. An understanding of women's self‐perception is important because it helps to explain how women make sense of the barriers and challenges they face in a male dominated culture and how they seek to attain positive outcomes for themselves. A comparison of women in the construction industry with women in other male‐dominated (legal) and female‐dominated (nursing) industries reveals little variation in self perceptions. Indeed, women in the construction industry emerge relatively positively, with the highest overall level of self‐esteem. This is encouraging and surprising, given the considerable evidence of significant barriers to entry and career progression for women in the construction industry, compared to other industries. It indicates that the construction industry is not a special case and that support strategies used in other industries are directly transferable, although the culture of the construction industry may make them more difficult to implement.     

Immunotoxicity of n‐nitrosamides: acute lesions and neoplasias of the lungs,the lymphoid system and of the gastro‐intestinal tract

A review of the reported effects, acute and neoplastic, induced by various N‐nitrosamides in animals and human cancer patients, indicate that these compounds can significantly depress the immune system, and may be involved in certain viral, bacterial and parasitic infections, including AIDS.     

May land use change reduce the water deficiency problem caused by reduced brown coal mining in the state of Brandenburg?

Surface mining alters the water regime not only locally, but also regionally. The reduced brown coal mining in the south-east of the state Brandenburg (Germany) leads to decreasing river discharge and consequently to a shortage in the water supply. Land use change is one possible option to counteract this development. In this simulation study, we explored the impact of temporary and permanent set-aside of arable land on Brandenburg’s regional water balance. Temporary and permanent set-aside were considered as major measures towards deintensification of agriculture. Simulations were performed using the regional ecohydrological model SWIM, which integrates hydrological processes, vegetation growth, erosion and nutrient dynamics. The model was used to simulate the consequences of different land use change scenarios on main components of the regional water balance. Changes in the use of arable land altered clearly its water balance. The impact of these changes on the regional water balance for Brandenburg did not exceed ±10% for its single components. Opposite tendencies were established in the simulations by contrasting effects of temporary and permanent set-aside of arable cropland. While temporary set-aside increased runoff from the whole area up to 6.7% due to lower evapotranspiration and higher soil moisture in arable land, the conversion of agricultural land within river corridors to meadows had an opposite effect on regional runoff (6.9% decrease) due to higher water retention coefficients and higher evapotranspiration losses. Therefore, only temporary set-aside may compensate to some extent for the anticipated decrease in river discharge.     

Australian project time‐cost analysis: Statistical analysis of intertemporal trends

In statistical analysis of intertemporal movements in time–cost relationships via the Bromilow model it is shown that for Ng et al.’s (2001) Australian data, the K value is not significantly different from unity. This is utilized to develop a new and simpler ratio measure of the time–cost relationship, which has the advantage of being obtainable for each project. A scatter plot and a statistical analysis of the project ratios indicate significant yearly fluctuations but no underlying trend. Assuming similar characteristics of the data from previous studies, equivalent average ratios are estimated and plotted, confirming Ng et al.’s visual appearance of a possible downward trend. However, the statistical analysis is inconclusive on the issue, there being insufficient data (six points) for a full analysis.     

Fractionation of total water soluble aluminium in extracts from peat and sand soil samples by ion‐exchange method followed by GF AAS

This study attempted the use ion‐exchange resins in order to fractionate total water soluble aluminium in extracts collected over acidic peat and alkaline sand soils. Extraction was performed in neutral and acidic conditions in order to imitate the behaviour of natural or acid rains. The total aluminium content in soil extracts and fractions was determined by graphite furnace atomic absorption spectrometry (GF AAS). In order to retain aqua Al³⁺ and hydroxycomplexes of aluminium Chelex 100 was used. It was found that fractionation of the aluminium in extracts depends strictly on the type of soil. When neutral spring water was used for the extraction the content of water soluble aluminium was found to be over two times higher in case of peat soil when compared with sand soil extract. Acidification of water by addition of HNO₃ and H₂SO₄ (2:1) pronounced in much extend the extraction efficiency of aluminium only form sand soils (over 10 times) but did not change proportion in fractionation of the particular aluminium species. Admittedly in the case of peat soils no significant increase in total aluminium content was observed but the concentration of cationic forms in acidic extract increased twofold when compared with the neutral extract.     

Safety climate in conditions of construction subcontracting: a multi‐level analysis

A multi‐level safety climate model was tested in the Australian construction industry. Subcontracted workers’ perceptions of the organizational safety response (OSR) and supervisor safety response (SSR) in their own organization and that of the principal contractor were measured using a safety climate survey administered at a large hospital construction project in Melbourne. One hundred and fourteen construction workers completed the survey, representing nine subcontractors engaged at the project. Two requisite conditions for the existence of group‐level safety climates, i.e. (1) within‐group homogeneity; and (2) between‐group variation were satisfied for perceptions of subcontractors’ OSR and SSR. This supports the contention that subcontractors working in a single construction project exhibit a unique group‐level safety climate. Subcontracted workers also discriminated between group‐level safety climates (i.e. the SSR) in their own and in the principal contractor’s organizations. The results suggest some cross‐level influence. Perceptions of the SSR were positively predicted by perceptions of the OSR in both the principal and subcontractor organizations. Perceptions of the OSR of the principal contractor were also a significant predictor of the perceived OSR and SSR in the subcontractor organizations. Perceptions of the subcontractors’ SSR were a significant predictor of the rate of lost‐time and medical treatment incidents reported by the subcontractor. Although perceptions of the principal contractor’s SSR were not directly related to subcontractors’ injury rates, they were a significant predictor of subcontractors’ SSR, revealing an indirect link. The results suggest that supervisory personnel (e.g. foremen and leading hands) play an important role in shaping safety performance in subcontracted workgroups.     

Trading properties after the earthquake: the rebuilding of eighteenth‐century Lisbon

This paper introduces the innovative system used in the reconstruction of Lisbon after the 1755 earthquake. Its findings are based on original documents that offer a detailed picture of the principles and methods established to convert the land and properties of the old city into the new and standardized gridded Plan. Implemented in the mid‐eighteenth century, the methodical system outlined was, undoubtedly, an important point of reference for the large‐scale urban improvement and redevelopment operations that would follow in nineteenth‐century Europe.     

Photodegradation of selected β-blockers in aqueous fulvic acid solutions: kinetics, mechanism, and product analysis

The photodegradation of the widely used β-blockers atenolol and metoprolol were investigated in the presence of fulvic acid (FA) under simulated sunlight. Both atenolol and metoprolol undergo indirect photodegradation in the FA solutions. The triplet excited state of FA (³FA^∗) was verified to be main reactive species responsible for the photosensitized degradation of β-blockers. An electron transfer mechanism for the interaction between β-blockers and ³FA^∗ was proposed on the basis of a series of experiments. Magnetic property of metal ions exhibited significant impact on photosensitized degradation. Diamagnetic metal ions such as Mg²⁺, Ca²⁺, Zn²⁺, and Al³⁺ negligibly affected the degradation. In contrast, paramagnetic metal ions including Mn²⁺, Cu²⁺, Fe³⁺, and Cr³⁺ markedly inhibited the reactions in the order of Cr³⁺ < Fe³⁺ < Cu²⁺ < Mn²⁺. The inhibition was related to the complexation ability with FA. By LC-ESI-MS/MS analysis, deisopropyl-atenolol (metoprolol) was identified as the main photosensitized product. The degradation pathways of β-blockers involving electron transfer processes were proposed. This finding strongly suggests that ³FA^∗ was important reactive species for the degradation of β-blockers in natural waters.     

Socio‐economic impacts of mine closure: a case study using satellite imagery

Mine closure normally leaves an adverse impact on the environment and society that, if left unattended, may last for years to come. In India the Raniganj Coalfields of Coal India Limited may be facing severe social and ground stability problems as a result of numerous old, abandoned mines. Already subsidence has occurred in a number of places, such as the Salanpur, Baraboni and Jamuria areas of the Raniganj coal fields. The study presented here highlights the socio‐economic problems faced by the area. Using remote sensing techniques the authors have assessed the socio‐economic factors of the area and they recommend various remedial measures to overcome the adverse impacts of mine closure.     

Differential uptake of U,Mo and Cu,by roots,stalks and seeds of oats grown on uranium‐rich soils

The uptake of U, Mo and Cu by oats grown in high uranium containing soils was investigated. Roots of the plant were found to constitute an effective barrier to U uptake, while that of Mo was pH dependent. Cu concentrations in the plant were independent of those of the other two metals.     

Tempo-spatial characteristics and influential factors of rockburst:a case study of transportation and drainage tunnels in Jinping Ⅱ hydropower station

Jinping Ⅱ hydropower station is located in a high in-situ stress region in Southwest China. During the excavations of the transportation and drainage tunnels, more than 460 rockburst events were recorded in the transportation tunnel and 110 in the drainage tunnel, which has a serious and negative influence on the tunnels' construction and the safety of staff and equipment. In the paper, the characters of rockburst patterns are analyzed for the transportation and drainage tunnels. The results are illustrated...     

Urban decay and the premature obsolescence of housing: A cross‐country examination of the basic economic determinants

Urban decay and the premature obsolescence of housing remain important problems in even the wealthiest countries. Many analysts maintain that the market allocation of housing and the attendant spatial class segregation in the housing market are strongly related to both phenomena. The analysis carried out in this paper, however, suggests that socio‐economic segregation in housing is a minor explanation at best. Substandard housing seems overwhelmingly a manifestation of the failure by governments to sufficiently subsidize the production of, and support the demand for, housing of a good standard. Countries such as Sweden that have effected the requisite resource transfers have enjoyed considerable success in eliminating substandard housing. Neither urban decay nor the premature obsolescence of housing seem caused in any meaningful sense by market failure.