Kajian ini dijalankan untuk menentukan kandungan nutrien dan antinutrien dalam kernel biji Mangifera pajang Kostermans (bambangan). Analisis proksimat untuk kernel biji bambangan menunjukkan komposisi nutriennya terdiri daripada 38.68% karbohidrat total, 3.08% protein, 4.79% gentian kasar, 9.85% lemak total, 2.23% abu total dan 41.38% air. Kernel ini juga mengandungi 2.04 mg sianogen glikosida/100 g sampel dan 0.64% tanin. Minyak yang diekstrak dari kernel biji bambangan telah menunjukkan ciri fizikokimia yang hampir sama seperti lemak koko. Takat lebur minyak ini adalah pada 34.87°C, indeks refraktif pada 1.458 dan nilai iodinnya adalah 32.97 mg iodin/100 g sampel lemak.
Perovskite solar cells based on series of inorganic cesium lead bromide and iodide mixture, CsPbBr3-xI x , where x varies between 0, 0.1, 0.2, and 0.3 molar ratio were synthesized by two step-sequential deposition at ambient condition to design the variations of wide band gap light absorbers. A device with high overall photoconversion efficiency of 3.98 % was obtained when small amount of iodide (CsPbBr2.9I0.1) was used as the perovskite and spiro-OMeTAD as the hole transport material (HTM). We investigated the origin of variation in open circuit voltage, Voc which was shown to be mainly dependent on two factors, which are the band gap of the perovskite and the work function of the HTM. An increment in Voc was observed for the device with larger perovskite band gap, while keeping the electron and hole extraction contacts the same. Besides, the usage of bilayer P3HT/MoO3 with deeper HOMO level as HTM instead of spiro-OMeTAD, thus increased the Voc from 1.16 V to 1.3 V for CsPbBr3 solar cell, although the photocurrent is lowered due to charge extraction issues. The stability studies confirmed that the addition of small amount of iodide into the CsPbBr3 is necessarily to stabilize the cell performance over time.
Electrochemical impedance spectroscopy (EIS) is a key method for the characterizing the ionic and electronic conductivity of materials. One of the requirements of this technique is a model to forecast conductivity in preliminary experiments. The aim of this paper is to examine the prediction of conductivity by neuro-fuzzy inference with basic experimental factors such as temperature, frequency, thickness of the film and weight percentage of salt. In order to provide the optimal sets of fuzzy logic rule bases, the grid partition fuzzy inference method was applied. The validation of the model was tested by four random data sets. To evaluate the validity of the model, eleven statistical features were examined. Statistical analysis of the results clearly shows that modeling with an adaptive neuro-fuzzy is powerful enough for the prediction of conductivity.
Many times a year natural gas transmission and distribution companies need to make new connections to pipelines to expand or modify their existing system through hot tapping procedure. This procedure involves the installation of a new pipeline connection while the pipeline remains in service, flowing natural gas under pressure. The hot tap procedure includes attaching a branch connection and valve on the outside of an operating pipeline, and then cutting out the pipe-line wall within the branch and removing the wall section, which is called object of coupon through the valve. During the hot tapping process a critical problems occurred when a coupon fell into the mother pipeline. To overcome this problem, a gamma-ray absorption technique was chosen whereby a mapping technique will be done to detect the coupon position. The technique is non-destructive as it applies Co-60 (5mCi) as a radioisotope sealed source to emit gamma radiation and a NaI(Tl) scintillation as detector. The result provided a visible representation of density profile inside pipeline where the coupon location can be located. This paper provides the detail of the technique used and presents the result obtained.
Thirty-eight normal volunteers and 10 patients with untreated thyrotoxicosis were each given 0.5 ml of Lugol's solution daily for 10 days. On days 0, 5, 10, 15 and 20, serum levels of T4, free T4, T3 and TSH (by sensitive immunoradiometric assay) were measured. In normal subjects, the serum concentrations of free T4 declined significantly at day 10 while TSH levels were significantly increased at days 5, 10 and 15. Serum levels of T4 and T3 did not change significantly. All the observed changes took place within the limits of normal ranges for the hormones mentioned. In contrast, in the thyrotoxic subjects, both T4 and T3 were significantly decreased at days 5 and 10, while serum TSH remained below detection limit (0.14 mU/l) throughout the study. Short exposure to excessive iodide in normal subjects affects T4 and T3 release and this effect could be partially overcome by compensatory increase in TSH. In thyrotoxicosis, lack of compensatory increase in TSH results in rapid decreases in T4 and T3 levels. The integrity of the hypothalamo-pituitary-thyroidal axis may be effectively assessed by measuring TSH response to iodide suppression, using a highly sensitive immunoradiometric assay.
Reactions of 5-benzyloxy-4-methylpent-2-enyl(tributyl)stannane with aldehydes promoted by bismuth(III) iodide were usefully stereoselective in favour of the (E)-1,5-anti-6-benzyloxy-5-methylalk-3-en-1-ols. Similar stereoselectivity was observed for reactions of analogous 5-benzyloxy-4-methylpent-2-enyl bromides with aldehydes when promoted by a low valency bismuth species prepared by reduction of bismuth(III) triiodide with powdered zinc so providing a "tin-free" procedure. The analogous reactions of 4-benzyloxypent-2-enyl(tributyl)stannane with aldehydes promoted by bismuth(III) iodide were also stereoselective but gave lower yields. Attempted 1,6-stereocontrol using these reactions resulted in only modest stereoselectivities. Aspects of the chemistry of the products were studied in particular their stereoselective conversion into aliphatic compounds with methyl bearing stereogenic centres at 1,5,9,13- and 1,3,5-positions along the aliphatic chain. Mechanistically, allylic organobismuth species may be involved in both sets of reactions but this was not confirmed although the similar stereoselectivities observed for both the bismuth(III) iodide mediated reactions of the pent-2-enylstannanes and the low-valency bismuth promoted reactions of the pent-2-enyl bromides are consistent with participation of similar intermediates.
The purpose of this study is to quantify the quality of the available imaging modes for various iodine-based contrast agent concentration in paediatric cardiology. The figure of merit (FOM) was defined as the squared signal to noise ratio divided by a patient dose related parameter. An in house constructed phantom simulated a series of vessel segments with iodine concentrations from 10% or 30 mg/cc to 16% or 48 mg/cc of iodine in a blood plasma solution, all within the dimensional constraints of a paediatric patient. The phantom also used test inserts of tin (Sn). Measurements of Entrance Surface Air Kerma (ESAK) and exit dose rate were performed along with calculations of the signal-to-noise ratio (SNR) of all the objects. A first result showed that it was favourable to employ low dose fluoroscopy mode and lower frame rate modes in cine acquisition if dynamic information is not critical. Normal fluoroscopy dose mode provided a considerably higher dose level (in comparison to low dose mode) with only a slight improvement in SNR. Higher frame rate cine modes should be used however when the clinical situation dictates so. This work also found that tin should not be intended as iodine replacement material for research purposes due to the mismatching SNR, particularly on small vessel sizes.
In this work, voltammetric study based on cetyltrimethylammonium bromide (CTAB) as an ion-pairing agent for the determination of iodine level in iodized table salt has been explored. CTAB was used as an intermediate compound between iodide (I-) and the electrode due to its ability to dissociate to produce cetyltrimethylammonium ions ([CTA]+). The [CTA]+ with a long hydrophobic alkyl chain can be directly adsorbed onto the surface of the working electrode, and this in turns coated the electrode with cationic charge and enhance the electrode ability to bind to iodide (I-) and other molecular iodine ions. A mixture of iodide and CTAB ([CTA]+I-) was prepared and potential of 1.0 V for 60.0 s was applied to pre-concentrate the solution on the working electrode causing the [CTA]+I- to oxidize to iodine (I2). The produced I2 immediately react with chloride ion (Cl-) from the electrolyte of hydrochloric acid (HCl) to produce I2Cl- and form ion-pair with CTA+ as [CTA]+I2Cl-. The linear calibration curve of the developed method towards iodide was in the concentration range of 0.5-4.0 mg/L with sensitivity of - 1.383 µA mg/L-1 cm-2 (R2 = 0.9950), limit of detection (LOD) of 0.3 mg/L and limit of quantification (LOQ) of 1.0 mg/L, respectively. The proposed method indicates good agreement with the standard method for iodine determination with recovery range from 95.0 to 104.3%. The developed method provided potential application as a portable on-site iodine detector.
The aim of this research is an evaluation of polyelectrolytes. In the application of zinc-iodine batteries (ZIBs), polyelectrolytes have high stability, good cationic exchange properties and high ionic conductivity. Polyelectrolytes are also cost-effective. Important component of ZIBs are cation exchange membranes (CEMs). CEMs prevent the crossover of iodine and polyiodide from zinc (Zn) electrodes. However, available CEMs are costly and have limited ionic conductivity at room temperature. CEMs are low-cost, have high stability and good cationic exchange properties. Herein, polyelectrolyte membranes prepared from carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) are examined. It is seen that an increase in the ratio of PVA leads to enhanced ionic conductivity as well as increased iodine and polyiodide crossover. ZIBs using polyelectrolytes having 75:25 wt.% CMC/PVA and 50:50 wt.% CMC/PVA show decent performance and cycling stability. Due to their low-cost and other salient features, CMC/PVA polyelectrolytes prove they have the capacity for use as cation exchange separators in ZIBs.
Peanut (Arachis hypogaea) is an important source of protein and lipid globally. The effect of superheated-steam roasting on quality of peanut oil was evaluated based on physicochemical quality parameters. Three roasting temperatures (150, 200, and 250 °C) were used for different periods of roasting time and the obtained results were compared with those of conventional roasting. At 250 °C, superheated-steam roasted peanuts yielded more oil (26.84%) than conventionally roasted peanuts (24.85%). Compared with conventional roasting, superheated-steam roasting resulted in lower oil color, peroxide, p-anisidine, free fatty acid, conjugated diene and triene, and acid values and higher viscosity and iodine values in the roasted peanut oil. These values were significantly different from each other (p
This aim of this research is to investigate thermal stability of virgin coconut oil, (VCO) which was heated at 190°C upon 40 days storage as compared to extra virgin olive oil (EVOO). The changes in fatty acids composition through (GC), Fourier Transform Infrared (FTIR) spectra, iodine value (IV) and total phenolic content were determined throughout the period of study. Results from GC showed that there was significant changes (P
Iodine deficiency is still prevalent worldwide and it is the main cause of goiter, thyroid dysfunction and mental retardation. The aim of the study was to determine the iodine status and goiter prevalence among the school children in Terengganu. The representative sample consists of 1163 primary school children aged 8-10 years old randomly selected from urban and rural schools in Terengganu using stratified systematic random sampling technique. Urinary iodine levels in spot urine were determined by in house modified micro-method while goiter assessment was carried out by palpation of thyroid gland. The status of iodine deficiency was determined by the median urinary iodine concentrations (UIC) and total goiter prevalence (TGP) in accordance with the WHO criteria. The result showed the median [inter-quartile range (IQR)] urinary iodine concentrations was 78.7µg/L (50.1µg/L -120.0µg/L) indicating the iodine intake was slightly lower than recommended range of 100 µg/L. The rural school children had a significantly lower Iodine levels (median UIC=72.4µg/L, IQR=46.7µg/L -113.0µg/L) than the urban school children (median UIC=87.7µg/L, IQR=54.5 µg/L - 127.5µg/L). The total goiter prevalence (TGP) was 5.7%. The prevalence of goiter was significantly higher in rural (TGP=6.9%) compared to urban areas (TGP=3.6%). The study revealed that school children in Terengganu showed mild iodine deficiency and the condition is more pronounced in children from rural areas. The findings emphasize the importance of intervention implementation, universal salt iodization to ensure sufficient intake of iodine among the Terengganu school children.
A study to measure frying quality and stability of rice bran oil (RBO) compared to palm olein (PO) was conducted. The oils were used to fry French fries continuously for six hours a day up to five days at a temperature of 185 ± 5°C. Oil samples were collected and analyzed for free fatty acid (FFA), peroxide value (PV), smoke point, p-anisidine value (p-AV), iodine value (IV) and colour. At the end of the frying period for both oil samples, FFA, PV, colour and p-AV were increased whereas the IV and smoke point decreased. The rate of FFA formation of RBO was slightly lower which increased from 0.142% to 0.66% compared to PO which was from 0.079% to 0.93%. The PV of RBO showed consistent increased from 3.9 meq/kg to 13.4 meq/kg whereas PO with initial value at 3.4 meq/kg increased to 34.6 meq/kg on the fifth day. Smoke point of RBO and PO progressively dropped from 235°C to 188°C and 220°C to 178°C, respectively. The level of p-AV for RBO increased from 12.19 to 32.65 from the initial to the end of frying day whereas PO had higher rate of changes in p-AV which was from 10.45 to 60.75. The IV decreased over frying time where IV of RBO decreased from 94.5 to 66.5 while IV of PO decreased from 50.9 to 44.6. The colour of RBO showed increased in redness and yellowness but PO was darker at the end of the frying trial. In general, RBO showed better stability than the PO in deep frying of French fries.
A review of current information related to the likely incidences of thyroid diseases in the aged population of Malaysia, raising issues such as the need for further epidemiological studies of iodine intake in relation to thyroid diseases within different geographical regions and population subtypes, the need for general country-wide iodization of salt, and the screening of elderly Malaysians for so-called “occult” thyroid diseases.
The oil quality parameters of the seed oil of Baobab (Adansonia digitata) were evaluated using standard methods of analysis. The Iodine value, Peroxide value, Saponification value were 86 g/100g, 4.08 mEq/Kg, 188 mg/g, respectively, for seed oil. The oil content of the kernel was higher 23% compared to the hulls that contain 5.4% oil. The kernel oil contains substantial quantities of calcium, potassium, and magnesium, which were found to be 4116, 2339 and 1629 mg/Kg, respectively. The fatty acid profile showed that oleic and linoleic were the major unsaturated fatty acids, whereas palmitic was the major saturated acid. The oil also, showed considerable amount of total phenolic content (TPC) and worthy antioxidant activity. Baobab oil has great nutritional and industrial potentials. It is therefore recommended that more and advanced research should be undertaken for this abundant source of natural nutritious oil.
The prevalence of goitre was determined in several communities in rural parts of Pahang. Urine specimens were collected randomly among the participants. Drinking water from various sources such as river and spring, and water from gravity feed systems was also collected to determine the iodine content by using the ashing method. The results were compared to that of Kuala Lumpur City. lt was found that the prevalence of goitre in rural areas was between 20 and 70% depending on village, ethnic group, age and gender. The interior parts of the jungle where Aborigines lived was moderately endemic with goitre prevalence of goitre more than 20% and urinary iodine content 2.0-5.0 μg I/dl). A nearby Malay traditional village which was studied had mild endemia (prevalence 10-30% and urinary iodine content 5.0-10.0 μg I/dl) while a Felda Malay resettlement scheme and Kuala Lumpur City did not have endemic goitre. Endemic goitre in rural areas was associated with low iodine content in drinking water. Even though Kuala Lumpur had low iodine content in its drinking water there was no endemic goitre, indicating that other factors were more important.
A flow injection analysis (FIA) method for the determination of four residual chlorine species, namely combined available chlorine (CAC), free available chlorine (FAC), total available chlorine (TAC) and chlorite (ClO2-) was developed using a flow-through triiodide-selective electrode as a detector. An important strategy of speciation studies utilized the kinetic discrimination of reactions between the CAC and FAC with Fe2+, which was applied to the speciation of FAC, CAC and TAC. The speciation of available chlorine species and chlorite (an oxychlorine species) was achieved by using the same set-up, but using flow streams of different pH. The effects of the pH of the carrier stream, the flow rate and the sample volume were studied. The method exhibited linearity from 2.8 x 10(-6) to 2.8 x 10(-4) M active chlorine (expressed as OCl-) with a detection limit of 1.4 x 10(-6) M. The selectivity of the method was studied by examining the minimum pH for the oxidation of iodide by other oxidants, and also by assessing the potentiometric selectivity coefficients. The proposed method was successfully applied to the determination of chlorine species in tap water, and disinfecting formulations where good agreement occurred between the proposed and standard methods were found.