In this present study, adsorptive membranes for Cr(VI) ion removal were prepared by blending polyethersulfone (PES) with hydrous ferric oxide (HFO) nanoparticles (NPs). The effects of HFO NPs to PES weight ratio (0–1.5) on the physicochemical properties of the resultant HFO/PES adsorptive membranes were investigated with respect to the surface chemistry and roughness as well as structural morphologies using different analytical instruments. The adsorptive performance of the HFO NPs/PES membranes was studied via batch adsorption experiments under various conditions by varying solution pH, initial concentration of Cr(VI), and contact time. The results showed that the membrane made of HFO/PES at a weight ratio of 1.0 exhibited the highest adsorption capacity which is 13.5 mg/g. Isotherm and kinetic studies revealed that the mechanism is best fitted to the Langmuir model and pseudo-second-order model. For filtration of Cr(VI), the best promising membranes showed improved water flux (629.3 L/m2 h) with Cr(VI) ion removal of 75%. More importantly, the newly developed membrane maintained the Cr(VI) concentration below the maximum contamination level (MCL) for up to 9 h.
Regional models of land use change are evaluated as a way of identifying land use pattern based on recent quantitative and probabilistic approaches. Differentiation between models in this area is the result of the approach to the concept of land use and type of indicators used in the modeling process. Since the determination of the optima land use pattern, due to the different uses of land based on the availability of regional capabilities and spatial difference in land use, depends on an integrated model, there must be a model that can assess the existing conditions of the region and present reasonable models of land use according to regional capacities and potentials. In this research, we developed a model to present the Optimal Land Use Allocation Pattern (OLUAP) for maximizing the advantages of change and determining the methods of influencing land use change priorities. This model uses spatial models and analysis, moderates the cost-benefit function, and calculates the allocation priorities of various areas based on regional conditions. The model results show that a wide scope of Nowshahr area is allocated to natural and agricultural uses. At the same time, a limited area has been assigned to urban and industrial uses. In addition, it shows that northern strip of the region due to higher accessibility of services and infrastructures is more suited than other regions to urban and industrial areas, and these two uses have first and second priority, respectively. Besides, according to the man-made environment and the special environmental conditions, the model allocates the central lowlands and southern parts sporadically to agricultural and natural areas as first and second priorities. Since the model is spatial optimization, the suggestions of the model show the OLUAP. Therefore, one can see the optimal condition for each plot and compare it with the existing land use. 相似文献
This study has attempted to estimate the energy consumption and emission of pollutants namely carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx) and non-methane volatile organic compounds (NMVOC) from the road transport sector in Malaysia from the year 2012 till 2040. This was done using the long-range energy alternatives planning (LEAP) model. Estimates of energy consumption and emissions were evaluated and analysed under a business-as-usual scenario and three other alternative fuel policy scenarios of biodiesel vehicles (BIO), natural gas vehicles (NGV) and hybrid electric vehicles (HEV). The aim of this study has been to identify the potential alternative fuel policies that would be effective in reducing the future growth of road transport energy consumption and emission in Malaysia. Results indicate that the NGV scenario contributes towards the highest reduction in road transport energy consumption followed by BIO and HEV. The NGV scenario also achieves highest mitigation of emission of all the four pollutants. In the case of CO2 emission, BIO scenario attains second highest mitigation, whereas in the event of CO, NOx and NMVOC emission, HEV scenario achieves second highest mitigation. 相似文献
Populations from different environmental habitats indicate variation in life history traits and these differences are mostly related to longevity, age and size at maturity. In this study, age structure, longevity, survivorship and sexual size dimorphism of Near Eastern fire salamander (Salamandra infraimmaculata) were assessed by means of skeletochronological analysis. Maximum lifespan was recorded to be twelve years in females and eleven years in males and age at maturity was estimated as three and four years for both sexes. Females had significantly larger SVL than that of males, while age structure and mean age did not differ between sexes. Age and body size were positively correlated with each other for both females and males. Since the populations of the Near Eastern fire salamander in Turkey are in decline, the present study which provides preliminary data on life history traits of this species could be helpful for future biological studies. 相似文献
Environmental and Ecological Statistics - Flash floods have devastating power due to their high rainfall intensities and short durations, causing serious damage to infrastructure and human life.... 相似文献
Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In
peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified
as driving significant environmental change. To date, there has been insufficient literature studying the link between changes
in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development
policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links
for future development policies. The objective is to generate insights on the changing process of land use/land cover and
landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over
the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated
by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process
aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s
and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia,
a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber
(first stage: 1900–1950s), oil palm (second stage: 1960s–1970s), and urban (third stage: 1980s–1990s) development that influenced
landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of
biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful
to development policy formulation, allowing diagnosis of the country’s “health” and sustainability. The final section outlines
the usefulness of landscape analysis in the policy-making process to prevent further fragmentation of the landscape and forest
loss in Malaysia in the face of rapid economic development.
Golden Horn is an estuary in Istanbul. It has connection with Marmara Sea directly and with Black Sea via Bosphorus, and was polluted by different kinds of industrial plants up to 1999. In addition to this, municipal wastewater of around one million people has been discharged to here. Greater part of the estuary was almost blocked off by sediment islands. Extensive effort was spent to dredge sediment in 1999. This created quite a convenient condition for aquatic medium in the estuary.In this research, the variations of chemical compositions of sediment bed were investigated to get clue about ecological conditions of the estuary. For that purpose, sediment samples were taken from 6 stations along the estuary in 2001, 2003 and 2004. The sediment samples were analyzed for inorganic and organic constituents. Meanwhile, water samples (from the surface and just above benthic mass) were also taken from the same 6 places and they were analyzed to verify the data from sediment samples. By this way, correlations between sediment mass and water body were determined. 相似文献
A study was carried out at some selected coastal areas of Malaysia to determine the present status of hydrocarbon pollution. Five sites were chosen and these include Pulau Langkawi and Pulau Ketam in the west coast, Tanjung Piai in the south, and Pulau Tioman and Kemaman in the east coast of Peninsular Malaysia. The levels of total hydrocarbon in the sediments are found to vary from 18.2 to 847.4 mg kg-1 with sediments from Pulau Langkawi and Tanjung Piai recorded the highest values (691.2 to 847.4 mg kg-1) while Kemaman and Pulau Ketam recorded the lowest values (18.2 to 59.8 mg kg-1). It was noted that these values are related not only to possible sources of hydrocarbon but also to the physical characteristics of the sediments analysed. Sandy sediment generally contains less hydrocarbon than clayey sediment. Further analyses of the sediment extracts indicate that the sources of the hydrocarbon pollution are predominantly petrogenic with significant contribution from biogenic hydrocarbon. 相似文献
Highland catchments in tropical regions are frequently subjected to soil erosion and the transport of chemicals downstream.
Any drastic changes in land use will increase the severity of these processes of land degradation. A simulation study using
GLEAMS (Groundwater Loading Effects of Agricultural Management Systems) was conducted at a catchment presently under tea farming
in Cameron Highlands, Malaysia. Soil, water and nutrient transport associated with several alternative land uses was studied.
In addition, the effect of a disruptive form of land clearing on soil, water and nutrient losses was also investigated. Modelling
with GLEAMS required information from field measurements and observations, laboratory analyses, guide tables, industry records,
maps and reports published by soil survey and meteorological departments.
The most critical step in simulating soil and water movement using GLEAMS is the identification of a representative flow sequence.
In the catchment under study, the representative flow sequence was overland flow–channel 1–channel 2. Input data on soil erodibility,
porosity and surface roughness were manipulated to represent various degrees and forms of disturbance to the surface soil
layer. For all land uses studied, the highest soil loss was predicted for the overland flow area where slope gradient is high
and the soil friable. The variations in soil loss, runoff and nutrient loss between landscape elements and between land uses
were consistent with soil erosion features observed in the field. Soil and nutrient losses were substantial for crops such
as cabbage that required land shaping activities and frequent ploughing of the soil. Predicted data on enrichment ratio of
specific surface (ERSS) are consistent with nutrient enrichment processes in the field and could prove to be useful in studies
on chemical transport in highland catchments. 相似文献
Phenolic chemicals with their very low taste and odour thresholds, high persistence and toxicity, are of growing concern as water pollutants. The compounds are known to exist in raw water as well as in treated water. The level of phenolic priority pollutants in water within the catchment area of the Linggi River Treatment Plant in Negeri Sembilan, Malaysia, which includes the Linggi river basin, was monitored. The 4-aminoantipyrin colourimetric method was used to determine total phenols whereas capillary column gas chromatography was used to determine the individual compounds. The results show that at most sampling stations, particularly those within the Seremban municipality, the level of phenols was found to exceed the recommended Malaysian standard of 2.0 g/L-1 for raw water. This is seen as the direct impact of industrial and urbanization of the area and clearly indicates the unhealthy state of the Linggi river. The results also indicate the need to improve the water quality if the river is going to be used as a source of raw water. 相似文献