Assessment on the distributions and exchange of anionic surfactants in the coastal environment of Peninsular Malaysia: A review

Author(s):  
Royston Uning ◽  
Suhaimi Suratman ◽  
Mohd Talib Latif ◽  
Nur Ili Hamizah Mustaffa
Author(s):  
P. P. Wong

Coastal environments of Southeast Asia have been discussed in Chapter 11. This chapter focuses on the utilization of the region’s coastal resources, reflecting not only its varied physical characteristics but also the traditional practices and more modern economic influences that have developed along the coastal regions. Historically, the region serves as an important link between trading routes to Western and Eastern Asia. Many sea battles were fought here between local potentates and foreign powers to win control of the spice trade. A number of the coastal villages developed into important coastal cities, e.g. Cebu, Malacca, Singapore, or in recent years, into coastal tourist resorts, e.g. Pattaya, Kuta. Within the region, there are still strong cultural traditions in the use of coast, although these are being eroded or replaced by more modern or economic practices. For example, the beach forms the traditional recreational area for farmers after the harvest season in Lombok and the east coast of Peninsular Malaysia. Traditionally, the Balinese attach a low economic value to the coast, but this has been replaced in modern times by new and high economic values for tourism, residence, and other uses. The demands for the coastal areas for different uses have various impacts, many of which are detrimental to the coastal environment and may lead to conflicts between users. This chapter relates people with the coastal environment in terms of living and non-living marine resources. Specifically, it discusses several major coastal uses, and their impacts and attempted solutions, to development-related problems. A holistic approach in coastal zone management to solve the problems is advocated, and the implementation and success of this approach assessed. This is also considered within the future and wide-ranging context of climate change and attendant sea-level rise. The definition of a ‘coastal zone’ in Southeast Asia is variable and difficult, as not all states have coastal zone management acts or legislation to define the coastal zone. For the purposes of this chapter, the coastal zone is taken as a variable area defined by not only biogeomorphological characteristics but also the major types of use.


1996 ◽  
Vol 91 (2) ◽  
pp. 209-216 ◽  
Author(s):  
S.L. Tong ◽  
F.Y. Pang ◽  
S.M. Phang ◽  
H.C. Lai

Author(s):  
E. Naranjo

Equilibrium vesicles, those which are the stable form of aggregation and form spontaneously on mixing surfactant with water, have never been demonstrated in single component bilayers and only rarely in lipid or surfactant mixtures. Designing a simple and general method for producing spontaneous and stable vesicles depends on a better understanding of the thermodynamics of aggregation, the interplay of intermolecular forces in surfactants, and an efficient way of doing structural characterization in dynamic systems.


2020 ◽  
Vol 14 (1) ◽  
pp. 34
Author(s):  
Faezah Pardi

This study was conducted at Pulau Jerejak, Penang to determine the floristic variation of its tree communities. A 0.5-hectare study plot was established and divided into 11 subplots. A total of 587 trees with diameter at breast height (DBH) of 5 cm and above were measured, identified and recorded. The tree communities comprised of 84 species, 63 genera and 32 families. The Myrtaceae was the most speciose family with 10 recorded species while Syzgium glaucum (Myrtaceae) was the most frequent species. The Myrtaceae recorded the highest density of 306 individuals while Syzgium glaucum (Myrtaceae) had the highest species density of 182 individuals. Total tree basal area (BA) was 21.47 m2/ha and family with the highest BA was Myrtaceae with 5.81 m2/ha while at species level, Syzgium glaucum (Myrtaceae) was the species with the highest total BA in the plot with value of 4.95 m2/ha. The Shannon˗Weiner Diversity Index of tree communities showed a value of 3.60 (H'max = 4.43) and Evenness Index of 0.81 which indicates high uniformity of tree species. The Margalef Richness Index (R') revealed that the tree species richness was 13.02. Myrtaceae had the highest Importance Value of 20.4%. The Canonical Correspondence Analysis (CCA) showed that Diospyros buxifolia (Ebenaceae) and Pouteria malaccensis (Sapotaceae) were strongly correlated to low pH. Dysoxylum cauliflorum (Meliaceae) and Eriobotrya bengalensis (Rosaceae) were correlated to phosphorus (P) and calcium ion (Ca2+), respectively. Therefore, the trees species composition at Pulau Jerejak showed that the biodiversity is high and conservation action should be implemented to protect endangered tree species. Keywords: Floristic variation; Tree communities; Trees composition; Pulau Jerejak; Species diversity


2020 ◽  
Vol 5 (1) ◽  
pp. 374
Author(s):  
Pauline Jin Wee Mah ◽  
Nur Nadhirah Nanyan

The main purpose of this study is to compare the performances of univariate and bivariate models on four time series variables of the crude palm oil industry in Peninsular Malaysia. The monthly data for the four variables, which are the crude palm oil production, price, import and export, were obtained from Malaysian Palm Oil Board (MPOB) and Malaysian Palm Oil Council (MPOC). In the first part of this study, univariate time series models, namely, the autoregressive integrated moving average (ARIMA), fractionally integrated autoregressive moving average (ARFIMA) and autoregressive autoregressive (ARAR) algorithm were used for modelling and forecasting purposes. Subsequently, the dependence between any two of the four variables were checked using the residuals’ sample cross correlation functions before modelling the bivariate time series. In order to model the bivariate time series and make prediction, the transfer function models were used. The forecast accuracy criteria used to evaluate the performances of the models were the mean absolute error (MAE), root mean square error (RMSE) and mean absolute percentage error (MAPE). The results of the univariate time series showed that the best model for predicting the production was ARIMA  while the ARAR algorithm were the best forecast models for predicting both the import and export of crude palm oil. However, ARIMA  appeared to be the best forecast model for price based on the MAE and MAPE values while ARFIMA  emerged the best model based on the RMSE value.  When considering bivariate time series models, the production was dependent on import while the export was dependent on either price or import. The results showed that the bivariate models had better performance compared to the univariate models for production and export of crude palm oil based on the forecast accuracy criteria used.


2018 ◽  
Vol 70 (1) ◽  
pp. 103-108
Author(s):  
A.R. Rafidah ◽  
◽  
A.R. Ummul-Nazrah ◽  
M.A. Mohd Hairul ◽  
◽  
...  

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