Preparation of nano mullite from activated kaolin and gibbsite at a low temperature

Suhanda Sutardi 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.3

Nanomullite powders were successfully prepared from activated kaolin and gibbsite. Kaolin activation was performed by the thermal treatment at 800 o C and sulfuric acid treatment. The activation process has changed kaolin structure to produce alumina, silica, and aluminosilicate phases, as given by XRD result. The XRD result was corroborated and was proved by the result of electron diffraction TEM analysis, the activated kaolin consisted of a-Al2O3, quartz, and mullite phases. Nanomullite was prepared from the activated kaolin, gibbsit, and sulfuric acid and was calcined at 400 o , 600 o , 800 o , and 1200 o C. Crystallization of the as-prepared mullite in the temperature range of 400 o -1200 o C produced mullite, α-Al2O3, and spinel phases at 400 o C. A further phase transformation of the mullite sample maintained mullite and α-Al2O3 phases at 1200 o C. The grain sizes of mullitepowders are found to be less than 100 nm at a calcination temperature of 1200 o C. The electron diffraction (ED) patterns of the calcined mullite are indexed to the mullite phase with the crystal plane orientations of (310), (030), (101), (001), (201), (040) and (121). These results are in agreement with the XRD result for the calcined mullite at 1200 o C.

Nutrient Requirements of Exercising Swamp Buffalo, Bubalus bubalis, from Materials Balance and In Vivo Body Composition by the Body Density Method. I. Aspects of Energy and Protein Metabolism in Working Cows

Mahardika, IG.,Sastradipradja, D.,Sutardi, T.,Sumadi, IK. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.5

Four young swamp buffalo cows of similar age ranging in weight between 280 to 380 kg and trained to do physical work were used in a study to determine energy and protein requirements for draught using a $4{\times}4$ Latin square designed experiment. The experiment consisted of field trials employing 4 levels of work load, e.g. no work as control, and loads amounting 450 to 500 Newton (N) pulled continuously for 1, 2 and 3 h daily for 14 consecutive days. Cows were fed king grass (Penisetum purpuroides) ad libitum and were subjected to materials balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus retained energy (RE). The results show that EE while not working ($EE_{resting}$) was $0.42kgW^{0.75}MJ/d$ and maintenance ME ($ME_m$) was $0.37kgW^{0.75}MJ/d$. ME requirement increased to 1.65 times maintenance for the work of 3 hours. The energy expended for doing exercise ($E_{exercise}$) was 9.56, 20.0 and 25.86 MJ/cow for treatments 1, 2 and 3 II, respectively. Fat retention was absent in all groups of working cows, but protein retention was only negative for cows undertaking 3 h work. The relationship between $E_{exercise}$ (MJ), work load (F, kN), work duration (t, h) and body mass (W, kg) was found to be: $E_{exercise}=(0.003F^{1.43}t^{0.93})/W^{0.09}MJ$. The maintenance requirement for digestible protein was $2.51kgW^{0.75}g/d$, whereas digestible protein for growth ($DP_{growth}$) and for work ($DP_{work}$) followed the equations: $DP_{growth}=[(258+1.25W^{0.75}){\Delta}Wkg/d]g$ and $DP_{work}=[12.59e^{0.95t}]g$, respectively The coefficients a, b and c for the calculation of $E_{exercise}$ components according to the Lawrence equation were found to be 2.56 J/kgW.m, 5.2 J/kg load carried.m and 0.29, respectively, thus efficiencies to convert ME into work were 0, 16.09, 27.3 and 32.44% for control, 1, 2 and 3 h/d work, respectively. ME and DP requirements for a 250 to 400 kg working buffalo cow allowing to growth up to 0.5 kg/d are presented.

Effect of sugar and citric acid as precursors in ZrO2 nanopowder preparation at low calcination temperatures

Rifki Septawendar,Bambang Sunendar Purwasasmita,Suhanda Sutardi,Naili Sofyaningsih,Wahyudi Kristanto 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.3

Zirconia nanopowder was successfully prepared using sugar and citric acid by a precursor calcination process, in which sugar was used as a gelling agent and citric acid as a catalyst. The effect of citric acid on this zirconia preparation is found out by the variable time of addition of citric acid on the preparation, namely SZG (before sugar) and SGZ (after sugar). The calcinations were conducted at 600οC and 800οC. XRD results show that at 600οC, t- and m-ZrO2 phases are identified in SZG, whereas t-ZrO2 is the only phase in SGZ. XRD analysis finds that both of the zirconia samples having had crystallites below 20 nm. At a high temperature of 800οC, two phases of zirconia are identified as t- and m-ZrO2 in both of the samples with different intensities. A Quanta FEG SEM study shows both of the zirconia samples at 800οC have homogenous microstructures and grain sizes less than 100 nm. A high resolution sophisticated SEM investigation shows that the SZG sample at 800οC has an average grain size below 50 nm. However, the effect of the citric acid addition time on the zirconia preparation is clearly visible in the zirconia phase transformation. The earlier addition of citric acid on the preparation gives two phases of zirconia in the final product at 600οC; and by contrast, the later addition of the acid after sugar on the preparation produces only t-ZrO2 phase.

The zirconia phase transformation in the preparation of nano zirconia by calcining a gel-emulsion precursor

Hernawan,Rifki Septawendar,Naili Sofiyaningsih,Suhanda Sutardi 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.5

Nano-ZrO2 was succesfully prepared by calcining a precursor of a zirconium gel-emulsion in oleic acid. The gel-emulsion process was started with the preparation of a gel zirconium hydroxide. The hydroxide gel was then mixed with oleic acid at various ratios and heated at 200 oC to give zirconia precursors. These precursors were succesfully calcined at 800 oC, 1000 oC,and 1200 oC, to give zirconia powder. The crystal structure and the particle morphology of the calcined powder were identified using XRD, SEM, and TEM. The XRD results show that monoclinic zirconia is formed dominantly with crystallite sizes ranging from 46.2 to 55.3 nm at 800 oC. Meanwhile, the SEM micrographs of the zirconia calcined at 800 oC show particles with a homogenous morphology having sizes below 100 nm. The TEM results indicate that that the individual grain diameters of ZrO2 were less than 60 nm. A lower oleic acid concentration leads to a more alkaline condition and more monoclinic zirconia formed; and a higher calcination temperature leads to a larger size of crystallites.

Nutrient Utilization, Body Composition and Lactation Performance of First Lactation Bali Cows (Bos sondaicus) on Grass-Legume Based Diets

Sukarini, I.A.M.,Sastradipradja, D.,Sutardi, T.,Mahardika, IG.,Budiarta, IG.A. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.12

A study on energy and protein utilization, and milk production of Bali cows on grass-legume diets was carried out using 12 first lactation cows (initial BW $263.79{\pm}21.66kg$) during a period of 16 weeks starting immediately post calving. The animals were randomly allotted into 4 dietary treatment groups R1, R2, R3 and R4, receiving from the last 2 months of pregnancy onwards, graded improved rations based on a mixture of locally available grass and legume feed ad libitum. R1 contained on a DM basis 70% elephant grass (PP, Penisetum purpureum) plus 30% Gliricidia sepia leaves (GS), R2 was 30% PP plus 55% GS supplemented with 15% Hibiscus tilliactus leaves (HT, defaunating effect), R3 and R4 were 22.5% PP+41.25% GS+11.25% HT+25% concentrate, where R3 was not and R4 supplemented with zinc di-acetate. TDN, CP and zinc contents of the diets were 58.2%, 12.05% and 18.3 mg/kg respectively for R1, 65.05%, 16.9% and 25.6 mg/kg respectively for R2, 66.03%, 16.71% and 29.02 mg/kg respectively for R3 and 66.03%, 16.71% and 60.47 mg/kg respectively for R4. Milk production and body weight were monitored throughout the experimental period. In vivo body composition by the urea space technique validated by the body density method and supported by carcass data was estimated at the start and termination of the experiment. Nutrient balance and rumen performance characteristics were measured during a balance trial of 7 days during the 3rd and 4th week of the lactation period. Results indicated that quality of ration caused improvement of ruminal total VFA concentration, increments being 52 to 65% for R2, R3 and R4 above R1, with increments of acetate being less (31 to 48%) and propionate being proportionally more in comparison to total VFA increments. Similarly, ammonia concentrations increased to 5.24 to 7.07 mM, equivalent to 7.34 to 9.90 mg $NH_3-N/100ml$ rumen fluid. Results also indicated that feed quality did not affect DE and ME intakes, and heat production (HP), but increased GE, UE, energy in milk and total retained energy (RE total) in body tissues and milk. Intake-, digestible- and catabolized-protein, and retained-protein in body tissues and milk (Rprot) were all elevated increasing the quality of ration. Similar results were obtained for milk yield and components with mean values reaching 2.085 kg/d (R4) versus 0.92 kg/d (R1) for milk yield, and 170.22 g/d (R4) vs 71.69 g/d (R1), 105.74 g/d (R4) vs 45.35 g/d (R1), 101.34 g/d (R4) vs 46.36 g/d (R1) for milk-fat, -protein, and -lactose, respectively. Relatively high yields of milk production was maintained longer for R4 as compared to the other treatment groups. There were no significant effects on body mass and components due to lactation. From the relationship $RE_{total}$ (MJ/d)=12.79-0.373 ME (MJ/d); (r=0.73), it was found that $ME_{m}=0.53MJ/kgW^{0.75}.d$. Requirement of energy to support the production of milk, ranging from 0.5 to 3.0 kg/d, follows the equation: Milk Prod. ($Q_{mp}$, kg/d)=[-2.48+4.31 ME($MJ/kg^{0.75}.d$)]; (r=0.6) or $Q_{mp}$=-3.4+[0.08($ME-RE_{body\;tissue}$)]MJ/d]; (r=0.94). The requirement for protein intake for maintenance ($IP_m$) equals $6.19 g/kg^{0.75}.d$ derived from the relationship RP=-47.4+0.12 IP; (r=0.74, n=9). Equation for protein requirement for lactation is $Q_{nl}$=[($Q_{mp}$)(% protein in milk)($I_{mp}$)]/100, where $Q_{nl}$ is g protein required for lactation, $Q_{mp}$ is daily milk yield, Bali cow's milk-protein content av. 5.04%, and $I_{mp}$ is metabolic increment for milk production ($ME_{lakt}/ME_{m}=1.46$).

Nutrient Requirements of Exercising Swamp Buffalo, Bubalus bubalis. II. Details of Work Energy of Cows and Its Relation to Heart Rate

Mahardika, I.G.,Sastradipradja, D.,Sutardi, T.,Sumadi, I.K. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.7

Four young swamp buffalo cows of similar age ranging in body weight (W) between 280 to 380 kg and trained for doing physical exercise were used in two consecutive experiments, each using a latin square design, to determine energy expenditure for draught. The experiments consisted of field trials using 4 levels of work load, i.e. no work as control and loads amounting 450 to 500 Newton (N) continuous traction for respectively 1, 2 and 3 h daily for 14 consecutive days for experiment 1, and no work, traction loads equaling 5, 10 and 15% of W for 3 h daily for 14 days for experiment 2. Heart rate during rest and exercise was monitored using PE-3000 HR monitor. Cows were fed only king grass (Penisetum purpuroides) ad libitum and were subjected to balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus RE. RE was calculated from the changes in body-protein and -fat measured before and immediately after the 14 d experimental period assuming an energy equivalent of 39.32 MJ/kg fat and 20.07 MJ/kg protein. $E_{exercise}$ ($EE_{work}\;-\;EE_{resting}$), which was the energy spent for doing the traction during 1, 2 and 3 h was 7.13, 15.45 and 19.90 MJ, respectively. $EE_{work}$ for the 1 h treatment group was 39.75 MJ/d equivalent to 1.30 times $EE_{resting}$. The values for the 2 and 3 h treatment groups were 1.75 and 1.86 times resting energy requirement, respectively. Absolute efficiency of work in all exercise trials of experiment 2 was around 27.28%. The increases of daily $E_{exercise}$ values were correlated to elevation of heart rate (HR) according to the equation $E_{exercise}=(0.270HR^{0.363}\;-\;1)$ MJ, while draught force related to heart rate according to the equation DF (N)=6.66 HR - 361.62. Blood glucose and triglyceride levels were gradually elevated with time during the course of exercise. Mean values of blood glucose were 91.7, 115.0 and 116.2 mg/dl for cows after 1, 2 and 3 h pulling loads at 15% W respectively as compared to 88.2 mg/dl prior to work. In the same order and treatment, mean blood triglyceride concentrations were 13.5, 13.3 and 14.8 mg/dl, and 11.5 mg/dl for control. For blood lactate, the values were 1.68, 1.63 and 1.66 mM, and 0.80 mM for control. Glucose was used as the major source of energy during the initial phase of exercise, but for prolonged work, fat will replace carbohydrate as the main substrate. Accumulation of lactate persisted for some time at the end of the exercise trials.

Mineral phase, microstructure, and Infra-Red characteristics of calcia-stabilized zirconia nanocrystallines synthesized from local zircon and slaked lime

Dede Taufik,Mikrajuddin Abdullah,Hernawan,Suhanda Sutardi,Rifki Septawendar 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.10

Nanocrystallines of calcia-stabilized zirconia are known to reveal excellent mechanical and high ionic conductivity propertieswhose depend on the calcia concentration. In this work, nanocrystallines of calcia-stabilized zirconia were synthesized fromzircon precursor and 7.5 weight % CaO at 1000 oC, 1200 oC, and 1400 oC. Phase transformation and microstructure evolutionwere investigated by an X-ray diffraction and a scanning electron microscopy. Another un-doped zirconia was also synthesizedfrom the local zircon by following the same procedure for comparison. A fully cubic form of the calcia-stabilized zirconia andcalcium zirconate were obtained at 1200°C having the crystallite sizes ranging from 55 to 87 nm and remained stable at1400 oC. Meanwhile, un-doped zirconia consisted of pure the monoclinic zirconia at 1200 oC and 1400 oC. High agglomerationis found in the calcia-stabilized zirconia particles at 1000 oC, whereas grain boundaries and interconnect are observed at1400 oC. The cubic crystal of zirconia has specific and different finger print characteristics in the infra-red spectrum comparedto the monoclinic zirconia.

Nutrient Balance and Glucose Metabolism of Female Growing, Late Pregnant and Lactating Etawah Crossbred Goats

Astuti, D.A.,Sastradipradja, D.,Sutardi, T. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.8

A study involving nutrient balances and radioisotope labeling techniques was undertaken to study energy and protein metabolism, and glucose kinetics of female crossbred Etawah goats, using 12 weaned (BW $14.0{\pm}2.0kg$), 12 late pregnant (BW $27.8{\pm}1.8kg$) and 12 first lactation does (BW $25.0{\pm}5.0kg$). Each class of animal was randomly allotted into 3 dietary treatment groups R1, R2 and R3, that received 100%, 85%, and 70% of ad libitum feed. The rations offered were pellets containing 21.8% CP and 19.3 MJ GE/kg, except for the lactating does who received pellets (17.2% CP and 18.9 MJ GE/kg) and fresh Penisetum purpureum grass. Energy and nitrogen balance studies were conducted during a two-week trial. Daily heat production (HP, estimated by the carbon dioxide entry rate technique), glucose pool and flux were measured. Equations were found for metabolizable energy (ME) and protein intake (IP) requirements for growing goats: ME (MJ/d)=1.87+0.55 RE-0.001 ADG+0.044 RP $(R^2=0.89)$ and IP (g/d)=48.47+2.99 RE+0.029 ADG+0.79 RP $(R^2=0.90)$; for pregnant does: ME (MJ/d)=5.92+0.96 RE-0.002 ADG+0.003 RP $(R^2=0.99)$ and IP (g/d)=58.34+5.41 RE+0.625 ADG-0.30 RP $(R^2=0.98)$; and for lactating does: ME (MJ/d)=4.23+0.713 RE+0.003 ADG+0.006 RP+0.002 MY $(R^2=0.86)$; IP (g/d)=84.05-5.36 RE+0.055 ADG-0.16 RP+0.068 MY $(R^2=0.45)$, where RE is retained energy (MJ/d), ADG is average daily gain in weight (g/d), RP is retained protein (g/d) and MY is milk yield (ml/d). ME and IP requirements for maintenance for growing goats were 0.46 MJ/d.kg $BW^{0.75}$ and 7.43 g/d.kg $BW^{0.75}$, respectively. Values for the pregnant and lactating does were in the same order, 0.55 MJ/d.kg $BW^{0.75}$ and 11.7 g/d.kg $BW^{0.75}$, and 0.50 MJ/d.kg $BW^{0.75}$ and 10.8 g/d.kg $BW^{0.75}$, respectively. Milk protein ranged from 3.06 to 3.5% and milk fat averaged 5.2%. Glucose metabolism in Etawah crossbred female goat is active, but glucose flux is low compared to temperate ruminant breeds which may implicate its role to support production.