727 research outputs found
Manufacturing Of Robust Natural Fiber Preforms Utilizing Bacterial Cellulose as Binder
We present a novel method of manufacturing rigid and robust short natural fiber preforms using a papermaking process. Bacterial cellulose acts simultaneously as the binder for the loose fibers and provides rigidity to the fiber preforms. These preforms can be infused with a resin to produce truly green hierarchical composites
The Impact of Supervisory Inputs on Postgraduate Students
Pengawasan telah menjadi isu utama dalam studi di sekolah pascasarjana. Pengawasan dapat didefinisikan sebagai hubungan orang per orang secara intensif dan interpersonal. Pengawas dirancang untuk dapat memfasilitasi perkembangan akademik mahasiswa baik terkait dengan tugas maupun penelitian mereka. Paper ini menunjukkan betapa kompleksnya bidang pengawasan terhadap mahasiswa, yang dipengaruhi oleh banyak faktor, di antaranya latar belakang sosial, kepribadian pengawas dan mahasiswa, hubungan yang berkembang di antara mereka, keahlian pengawas, dan masalah-masalah yang dihadapi oleh para mahasiswa. Paper ini mendiskusikan pentingnya input-input kepengawasan dalam proses pengawasan, dan juga meneropong hakikat interaksi sosial antara pengawas dengan mahasiswa. Sasaran yang dituju dalam paper ini adalah untuk mengembangkan pengawasan yang efektif terhadap mahasiswa sekolah pascasarjana guna menghasilkan modal sumber daya manusia yang unggul.
Kata kunci : pengawasan, mahasiswa pascasarjana, input kepengawasan, dan
pengawasan efekti
Mineralogy and Genesis of Soils in Uuiversiti Pertanian Malaysia, Serdang, Selangor
Soils of Universiti Pertanian Malaysia were surveyed and studied in order to determine their mineralogy and genesis. The results of the study showed that there were four major soil series on the Universiti Pertanian farm. Two of these series, namely Melaka and IVlunchong Series, were taxonomically classified as Tropeptic Haplorthox, while the other two, namely Serdang and Bungor Series, were classified as Typic Paleudult.
The structure of the soils was found to be weak. The texture was clay in the case of Melaka, Munchong and Bungor Series and sandy clay loam in the case of Serdang Series. Melaka Series soil which contained petroplinthite occur as capping on top of hills. Soils of Munchong, Bungor and Serdang occur either on the slope or on the lower position than Melaka Series.
All soils were extremely weathered. The dominant clay minerals were kaolinite, gibbsite and goethite;
2:1 type of clay mineral was virtually absent, except possibly some illite in Melaka Series. The pH was low,
and so were exchangeable cations, CEC and %base saturation. On the other hand, exchangeable Al and H
were significantly hig
Phytoremediation of heavy metals with several efficiency enhancer methods
It is no doubt that the contamination of water, air and soil has worsened, and this occurs as a result of the increase in population. However, the need for remediation technologies has to be seriously considered. Phytoremediation is one of the remediation techniques with a relatively slow procedure and low efficiency. This review covers some of the biological, chemical, physical, physico-chemical and genetic methods, which were applied in parallel with phytoremediation, in an attempt to help increase the efficiency in the remediation of air, soil and water. These include lowering the pH and increasing the electrode potential (Eh), as well as using chelating agents and micro-organisms (arbuscular mycorrhizal fungi (AMF) and plant growth promoting rhizobacteria (PGPR)).Among the introduced methods, an appropriate application of the PGPRs is one of the most useful and environmentally friendly techniques which is currently considered as a useful process in phytoremediation. As a result of the discovering of these new methods, multi-approaches have been executed for a faster and higher removal rate of the contaminants, with a consequent increase in the efficiency of phytoremediation, as compared to single techniques
Phosphate sorption by active acid sulfate soils of Peninsular Malaysia
Phosphate sorption data of four soil samples representing two soil series (Sedu and lawa Series; both Typic
Sulfaquepts) from Peninsular Malaysia were described by the Langmuir II sorption model. Lim Chin, Raja Muda
and Kuala Linggi soils represent Sedu series, while the soil sample from Serkat represent Jawa Series. The phosphate
sorbed by the four soil samples conformed to the Langmuir II adsorption isotherm. Lim Chin and Raja Muda
estate soils have r values of 0.98 and 0.99, respectively, while Serkat and Kuala Linggi soils have r values
of 0.96 and 0.95, respectively. Phosphate adsorption maxima and buffer capacities were higher in the Sedu soils
(Lim Chin and Raja Muda Estate) than in Jawa (Serkat) and the Sedu soil (Kuala Linggi). Liming of the Sedu
Soil (Raja Muda Estate) and Jawa soil (Serkat) at 1 t ha- I reduced phosphate sorbed by 3.1 and 13.1 percent,
respectively. Rates greater than 2 t ha-J of lime increased the P sorptive capacities of the soils
Laboratory Studies on the Release of Cations and Anions in Acid Sulfate Soils from Pulau Lumut,Selangor
Acid sulfate soils in Peninsular Malaysia are characterized l7y low pH and high amounts of At. Alleviation of toxic
ions in the soils l7y controlled drainage is recommended. However, potential acidity remains in the soils due to slow
release of toxic ions during mineral weathering. A study was conducted to determine the release of Al and other ions
l7y repetitive extraction of samples from the field and l7y aerobic incubation of samples in the laboratory. The results
showed that Al was released continuously from the soils even after the sixth extraction. When the soils were allowed
to undergo free oxidation under aerobic conditions Al, Mn, Fe, Ca, Mg, K, Na and S were released into the soil
solutions due to breakdown of clay minerals. Activities of these ions increased significantly, resulting in an increase
of electrical conductivity of the soil solution. Additionally, pH of the soil solution dropped. These commonly observed properties of acid sulfate soils have great implications on their management practices
Virtual Collaborative R&D Teams in Malaysia Manufacturing SMEs
This paper presents the results of empirical research conducted during March to September 2009. The study focused on the influence of virtual research and development (R&D) teams within Malaysian manufacturing small and medium sized enterprises (SMEs). The specific objective of the study is better understanding of the application of collaborative technologies in business, to find the effective factors to assist SMEs to remain competitive in the future. The paper stresses to find an answer for a question “Is there any relationship between company size, Internet connection facility and virtuality?”. The survey data shows SMEs are now technologically capable of performing the virtual collaborative team, but the infrastructure usage is less. SMEs now have the necessary technology to begin the implementation process of collaboration tools to reduce research and development (R&D) time, costs and increase productivity. So, the manager of R&D should take the potentials of virtual teams into account
Biostabilised icosahedral gold nanoparticles: synthesis, cyclic voltammetric studies and catalytic activity towards 4-nitrophenol reduction
A green and cost-effective biosynthetic approach for the preparation of icosahedral gold nanoparticles (AuNPs) using an aqueous leaf extract of Polygonum minus as reducing and stabilising factor is described. The reduction of Au3+ ions to elemental Au rapidly occurred and is completed within 20 minutes at room temperature. The size of the nanoparticles is highly sensitive to the AuCl4 −/leaf extract concentration ratio and pH. Transmission electron microscopy and X-ray diffraction data indicated that the nanoparticles were in a crystalline shape (face-centred cubic), mostly icosahedral and nearly monodispersed with an average size of 23 nm. Cyclic voltammetric studies suggested that flavonoids, such as quercetin and myricetin present in the leaf extract had a tendency to donate electrons to Au3+ ions and the formation of elemental Au was possible due to the transfer of electrons from these flavonoids to Au3+ ions. Infrared absorption of the AuNPs and the leaf extract revealed that the oxidised (quinone) form of quercetin and myricetin were presumably the main stabilising agents in the formation of stable nanoparticles. The present biosynthesis of AuNPs was simple, rapid, cost-effective and environmentally friendly. The newly prepared biostabilised icosahedral AuNPs show good catalytic activity in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP)
Organic Carbon Determination in Acid Sulphate Soils
Pyrite is almost exclusively present in the reduced zone of acid sulphate soil Profiles. This pyrite is believed to
interfere with determination of Cmg in the soils by the wet combustion method using Cr2o7 A study was
conducted to determine an accurate and reliable method for estimation of Cmg in acid sulphate soils in Malaysia
containing variable amounts of pyrite. Some of the established methods of carbon (C) determination were tested
against Carbon Determinator (Leco IR-312) which was regarded as the standard method. It was found that the
interference of pyrite in the determination of C in acid sulphate soils by wet combustion was minimal. The total
oxidation procedure was found to be the most reliable and accurate method for determination of C in acid
sulphate soils in the absence of Carbon Determinator. The Walkley-Black method underestimated, while the loss
on ignition method overestimated the Cmg content in the soils
THE ROW-COLUMN CONFOUNDED 2\u3csup\u3em\u3c/sup\u3eX4\u3csup\u3en\u3c/sup\u3e FACTORIAL DESIGN AND ITS DIFFERENT FRACTIONS
The row-column confounded 2mX4n factorial designs and its different fractions can be constructed and analyzed using pseudo factors in the 4n portion. (Examples are shown
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