Fabrication of Sub-Micron Near Stoichiometric NdFeB Magnetic Powder through HDDR Processing Route

Homogenized Near-Stoichiometric NdFeB alloys of composition Nd12.7FesuB6.o and Nd12.2Fes1.2Bs.9Zro.1 were Hydrogenated and disproportionate at 850°C for 30 minutes. All Nd2Fe14B phase were fully converted into NdH3, Fe38 and Fe. The recombination process produces sub-micron sizes ( ~ 0.3 μm) of Nd2Fe148 grains at an optimum temperature of 880°C. Zr addition into the NdFeB alloy inhibits grain growth during the recombination process

Effect Of pH Condition During Hydrothermal Synthesis On The Properties Of Hydroxyapatite From Eggshell Waste

Hydroxyapatite (HA) powders were synthesized using eggshell waste through hydrothermal method to develop bioceramics materials for medical applications. The effects of the pH conditions during the synthesis on the phase behaviour, crystallite size, crystallinity and morphology of as-synthesized ceramic powders were evaluated. The XRD patterns showed that HA was the only main phase present in the as-synthesized powder after being calcined at 400°C. However, EDX measurement detected the presence of Mg as trace element which originated from the eggshell as starting materials. The crystallite size and crystallinity of the HA powders were increased when the powders were synthesized in acidic condition as compared to basic condition. FESEM images showed that HA powder with nano-sized rods and spherical morphologies were obtained from the powders that were synthesized at pH 5, while the powder particles synthesized at the basic condition at pH 9 produced elongated rodshape particles. The PSD results showed that the synthesized HA was in agglomerated form which was also confirmed by FESEM images

Screen-printed ceramic based MEMS piezoelectric cantilever for harvesting energy

Screen-printing technology provides a convenient method in fabricating thick-film conductive circuits and devices in the past few decades. Conventionally, piezoelectric thick-film is printed on alumina substrate with high mechanical Q-factor and resonates at higher frequency outside the range of ambient vibration. As the piezoelectric charge generation is proportional to the mechanical stress on the material, therefore the substrate can be removed in order to lower the natural frequency of the structure. In this paper, a series of piezoelectric ceramic cantilevers were fabricated in the form of free-standing cantilever. An additional layer of ceramic was also introduced to the upper and lower electrode to prevent delamination. The issue of zero resultant stress for the sandwiched piezoelectric cantilever was solved by repeating the electrode-PZT-electrode layer to form a multilayer structure. It was found from the experiment that an electrical output power of 32 μW was generated when it operates at its resonant frequency at 403 Hz

Top spray fluidized bed granulated paddy urea fertilizer

Top spray granulation process is a common technique used widely in pharmaceutical, food and special chemical modification for fertilizer manufacturing. Nevertheless, there is still a lack of studies regarding to the description of controlled parameters with dynamic correlation in targeting to produce urea granules. Thus, this research was carried out to introduce the crucial applied process parameters using top spray technique for paddy urea fertilizer production. The acquisition process parameter readings were verified by obtained yield of urea granules (UG) which featured as an optimum particle diameter size from 2 mm to 6 mm with reasonable hardness (crush strength) in range 2.0 kg/granule to 4.0 kg/granule, these criteria were required as a slow - release mechanism during soil adsorption interaction in paddy field to reduce amount of fertilizer consumption. Three significant parameters have been selected namely as air inlet temperature, the viscosity of binder solution and rate of top spraying from starch liquid binder to generate greater UG size from wet granulation interaction with smooth coalescence and consolidation growth . The data classification was screened by One-Factor-at-a-Time (OFAT) 101 method and supported by 2 levels and 3 factors (23 ) of full factorial design for clear description to vindicate the critical parameter required during urea granulation using fluidized bed granulator corresponds to low energy consumption and economical process. The obtained parameter readings and findings of UG features were useful to be applied further for detail investigation on next stage regarding to agglomeration profile and mechanism using CCD camera and PDA monitoring devices

Entrepreneurial Potential: An Exploratory Study Of A Community In Johor

Two frequently cited personal traits associated with entrepreneurial potential are internal locus of control and innovativeness. This paper hypothesizes that internal locus of control and innovativeness is sufficient to explain entrepreneurial potential. This hypothesis was tested on a set of 124 responses to a survey did to a community in Johor. Eighteen items in the survey instrument were used to construct scales for innovativeness and locus of control. Items for the innovativeness scale were adapted from the Jackson Personality Inventory while items used for the locus of control scale were adapted from Rotter’s I-E scale. The results found an increased likelihood of an internal locus of control and innovativeness that support entrepreneurial orientation. To be motivated to act, potential entrepreneurs must perceive themselves as capable and psychologically equipped to face the challenges. This work has been supported by Universiti Teknikal Malaysia Melaka (UTeM) and Ministry of Higher Education Malaysia. Keywords: Entrepreneurial Potential, Locus of Control, Innovativeness,Communit

Statistical evaluation of the production of urea fertilizer-multiwalled carbon nanotubes using Plackett Burman experimental design

Abstract Plant growth rate is significantly dependent on application of nitrogenous fertilizer which mainly contributed by urea fertilizer (UF). Nanotechnology advancements in nutrition strategies for plants have attempted to assist plant nutrition for efficient plant growth. The development of carbon nanomaterials (NMs) including Multi-walled carbon nanotubes (MWNTs) in conjunction with the advancement in biotechnology has expanded their application area of in the field of agriculture. The aim of the work is to identify the significant process parameters to attach urea fertilizer (UF) onto MWNTs. The UF-MWNTs was than characterized optically and chemically to confirm their bonding. Comparison study was also conducted between UF-MWNTs and UF-functionalized {MWNTs} on total N content bonding to the MWNTs. The surface functional groups produced from functionalization process are essential for further modification of {MWNTs} and facilitate the separation of nanotube bundles into individual tubes. Optical, vibrational spectroscopy and chemical characterization were conducted on the samples using TEM, FT-IR and total N analysis confirmed the successful bonding of urea onto MWNTs. Plackett-Burman Experimental Design showed, two out of nine investigated parameters (amount of functionalized {MWNTs} and percentage of functionalization) were found significant in producing successful attachment of {UF} onto functionalized {MWNTs} (fMWNTs)

Urea impregnated biochar to minimize nutrients loss in paddy soils

Rubber wood sawdust (RWSD) is converted into a porous form of biochar through the slow pyrolysis process. In this study, it is used as a green binder to bind the urea together and form a fertilizer. The objective of the current research is to investigate the effect of biochar impregnation with urea on the N-nutrients retention in soils. The biochars were produced at heating temperatures of 300 °C and 700 °C for 3 hours with continuous nitrogen gas purging at 30 ml/min and a constant heating rate of 5 °C/min. The obtained biochars were characterized by XRD, Boehm titration, pH alkalinity, BET specific surface area and SEM. Boehm titration demonstrated a reduction of acidic functional groups with the increase of heating temperature, recorded as 1.3 and 0.3 mmol/g respectively for 300 °C and 700 °C. Conversely, biochar produced at higher temperature was reported to have a larger specific surface area of 5.4 m2/g. The impregnation was carried out on both biochars produced with molten urea. Results from mineralization showed that the sample with impregnation retained more nutrients in the soil compared to the un-impregnated sample, manifesting biochar as a potential material to be impregnated with urea for slow release and better nutrients retention in s

Characterization of Biochar Derived from Rubber Wood Sawdust through Slow Pyrolysis on Surface Porosities and Functional Groups

Biochars were prepared by conducting slow pyrolysis of rubber wood sawdust (RWSD) derived from sawn timber. Eventhough researches on preparation of biochar from biomass have been reported by many researchers, limited work has been reported for investigation of biochar RWSD for its surface porosities and functional groups. Surface porosity of biochars provides a suitable dimension for cluster of microorganism to grow and higher porosity for better water holding capacity. Surface functional groups contain oxygen may help to improve the soil fertility by increasing the cation and anion exchange capacities to reduce the nutrient leaching in soil. The pyrolysis process was carried out at temperatures ranging between 300 °C to 700 °C at the heating rate of 5 °C/min for 3 hours with continuous nitrogen purging. The influence of pyrolysis temperatures on the biochars pores were investigated by using X-Ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) surface analysis and Scanning Electron Microscopy (SEM). The surface functional groups were examined by Fourier Transform Infrared (FT-IR). SEM analysis clearly showed the development of well-defined pores distributed on biochars surface. It was found that the maximum BET surface area and total pore volume were 5.493 m2/g and 0.0097 cm3/g respectively for biochar pyrolysis at 700 °C. The FT-IR spectrum analysis showed the functional groups decreased with the increasing of pyrolysis temperature. The results highlighted the effect of pyrolysis temperature on biochar pores accumulative that associated with soil fertility and nutrient retention in soil which could be beneficial to the agricultural industries

Urea functionalized multiwalled carbon nanotubes as efficient nitrogen delivery system for rice

This paper utilized urea functionalized multiwalled carbon nanotubes fertilizer as plant nutrition for rice to understand fully their mechanism of interaction. Surface modification of multiwalled carbon nanotubes was treated by nitric acid at different reflux times. The individual and interaction effects between the design factors of functionalized multiwalled carbon nanotube amount and functionalization reflux time with the corresponding responses of nitrogen uptake and nitrogen use efficiency were structured via the Response Surface Methodology based on five-level central composite design. The urea functionalized multiwalled carbon nanotubes fertilizer with optimized 0.5 weight% functionalized multiwalled carbon nanotubes treated at 21 h of reflux time achieve tremendous nitrogen uptake at 1180 mg/pot and NUE up to 96%. The FT-IR results confirm the formation of acidic functional groups of functionalized MWCNTs and UF-MWCNTs. The morphological observation of transmission electron microscopy shows extracellular regions to be the preferred localization of functionalized multiwalled carbon nanotubes in fresh plant root cells independent of their size and geometry. Penetration into the plant cell results in breaching of graphitic tubular structure of functionalized multiwalled carbon nanotubes with their length being shortened until ∼50 nm and diameters becoming thinner until less than 10 nm. The capability to agglomerate after translocation into the plant cells alarms potential cytotoxicity effect of functionalized multiwalled carbon nanotubes in agriculture. These work findings have suggested using urea functionalized multiwalled carbon nanotubes for effective nutrient delivery systems in rice plant. © 2019 Vietnam Academy of Science & Technology

Urea Functionalized Multiwalled Carbon Nanotubes As Efficient Nitrogen Delivery System For Rice

This paper utilized urea functionalized multiwalled carbon nanotubes fertilizer as plant nutrition for rice to understand fully their mechanism of interaction. Surface modification of multiwalled carbon nanotubes was treated by nitric acid at different reflux times. The individual and interaction effects between the design factors of functionalized multiwalled carbon nanotube amount and functionalization reflux time with the corresponding responses of nitrogen uptake and nitrogen use efficiency were structured via the Response Surface Methodology based on five-level central composite design. The urea functionalized multiwalled carbon nanotubes fertilizer with optimized 0.5 weight% functionalized multiwalled carbon nanotubes treated at 21 h of reflux time achieve tremendous nitrogen uptake at 1180 mg/pot and NUE up to 96%. The FT-IR results confirm the formation of acidic functional groups of functionalized MWCNTs and UF-MWCNTs. The morphological observation of transmission electron microscopy shows extracellular regions to be the preferred localization of functionalized multiwalled carbon nanotubes in fresh plant root cells independent of their size and geometry. Penetration into the plant cell results in breaching of graphitic tubular structure of functionalized multiwalled carbon nanotubes with their length being shortened until ∼50 nm and diameters becoming thinner until less than 10 nm. The capability to agglomerate after translocation into the plant cells alarms potential cytotoxicity effect of functionalized multiwalled carbon nanotubes in agriculture. These work findings have suggested using urea functionalized multiwalled carbon nanotubes for effective nutrient delivery systems in rice plant