bluuebunny/crossref_metadata_2025 huggingface dataset:
PHASE TRANSFORMATION IN THE FORMATION OF FAUJASITE FROM FLY ASH
Authors: Sutarno Sutarno , Arryanto Yateman
Published: January 2019

Faujasite was hydrothermally synthesized from fly ash at 100oC in alkaline solution by reflux with 5M HCl and fusion with NaOH pretreatments. Phase transformation in the formation of faujasite was performed by variation of NaOH/fly ash weight ratios and hydrothermal times. The solid products were characterized by X-ray diffraction method. Results showed that faujasite was formed through dissolution of fly ash components such as quartz, mullite and amorphous aluminosilicates followed by crystallization to form faujasite. Arranging the NaOH/fly ash weight ratio as well as hydrothermal time can selectively form faujasite. Faujasite with crystallinity of 97.06%, Si/Al ratio of 2.68, and specific surface area of 452.93 m2/g was successfully formed using NaOH/fly ash weight ratio of 1.2 for hydrothermal time of 72 hours. In more concentrated alkaline solution as well as for longer hydrothermal time, faujasite was completely transformed into hydroxysodalite as the final product. Keywords: fly ash, faujasite, and phase transformation.
UTILIZATION OF Penaus monodon SHRIMP SHELL WASTE AS ADSORBENT OF CADMIUM(II) IN WATER MEDIUM
Authors: Cahyaningrum Sari Edi , Amaria Amaria
Published: January 2019

Utilization of shrimp shell has been optimum so that in this research preparation of adsorbent chitosan from shell of shrimp (Penaus monodon) as raw materials for cadmium(II) adsorption was carried out. The chitin was made by the deproteination, demineralization; chitosan was prepared by chitin deacetylation. This work was started with Infra Red Spectroscopic identification of functional group. Percentage of deacetylation was determined also by Infra Red Spectroscopy. Contant of nitrogen was determined by Kjeldhal method. The isotherm adsorption Langmuir model was employed for the determination of the energy and the capacity in adsorption. Result showed that chitosan could be isolated from shrimp shell waste with % deacetylation degree of 79.80 and % nitrogen 7.11. Cadmium(II) was chemically adsorbed on chitosan involving energi adsorption of 32.27 kJ/mole. Adsorption capacity of cadmium(II) was 6.35 x 10-5 mole/g. The constant adsorption rate k, was 0.91 x 10-3 s-1 and equilibrium adsorption desorption are K = 10.28 x 103. The ability adsorption of chitosan in real waste has the efficiency of 90%. Keywords: adsorption, cadmium(II), chitosan
DETERMINATION OF VANILLIN IN VANILLA (Vanilla planifolia Andrews) FROM LAMPUNG INDONESIA BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
Authors: Sujalmi Siti , Suharso Suharso , Supriyanto R , Buchari Buchari
Published: January 2019

This paper describes a reverse-phase high performance liquid chromatographic (HPLC) method for the separation, identification and quantification of vanillin in ethanolic extracts of cured vanilla. The fresh green beans were cured by three methods: scalding in hot water, drying in the oven, and drying in the sun. Two treatments for the cured beans before extraction, there were cutting cured vanilla about 2.5 cm and not cutting. The extraction was with Soxhletation and percolation method in 99.9 % ethanol. The vanillin was separated on C18 column using a mobile phase gradient of methanol  - acidified water (10-90), detection at 280 nm. The HPLC technique allows a more accurate means of determining the vanillin  content of vanilla than  the spectrophotometric method .   Keywords: Vanilla planifolia Andrews, Vanillin, HPLC
EFFECT OF ACID CONCENTRATION ON CHARACTERS OF SILICA GEL SYNTHESIZED FROM SODIUM SILICATE
Authors: Nuryono Nuryono , Narsito Narsito
Published: January 2019

In this research, synthesis and characterization of silica gel from sodium silicate through sol-gel process using H2SO4, HCl, and citric acid have been investigated. Synthesis was carried out by mixing and stirring  20 mL of H2SO4, HCl or citric acid  at certain concentration with 50 mL of sodium silicate solution (Na2O 0.17 M and SiO2 0.61 M) for one hour and let to form gel.  The gel was washed with distillated water, and dried in an oven at 100 oC. Characterization of silica gel was carried out by determination of acidity, water adsorption capacity, and water content. Identification of functional group and structure were identified using x-ray diffractometer (XRD) and infrared (IR) spectrophotometer, respectively.  Results showed that at a range of investigated concentration (0.6 - 3.0 M) the increase of concentration, formation of gel with H2SO4 tended to be faster, but with HCl and citric acid to be slower. The increase of acid concentration caused water content, water adsorption capacity, and acidity of the silica gel resulted with HCl and citric acid tended to be increased, increased, and increased, but with H2SO4 to be decreased, increased, and decreased, respectively. Based on the IR spectra and XRD data, it could concluded that the synthetic silica gels contained silanol (Si-OH) and siloxane (Si-O-Si) and were amorphous, showing similar pattern to kieselgel G 60 produced by Merck.   Keywords: silica gel, adsorption capacity, sodium silicate, acidity
STUDY OF REACTION OF TRANS-[Pt(15NH3)2(H2O)2]2+ WITH N-ACETYL-L-CYSTEINE
Authors: Hadi Sutopo , Appleton Trevor G
Published: January 2019

A study of the reaction between trans-[Pt(15NH3)2(H2O)2](NO3)2 and N-acetyl-L-cysteine (H3accys) was undertaken to confirm the identity of the products formed. In alkaline solution, the platinum products observed were mononuclear species, while in acidic solution, the oligomeric products were obtained. The mass spectrometry of the reaction in alkaline solution showed a sulfur-bridged dinuclear platinum(II) species, trans-[{Pt(H2accys-S)2(15NH3)2}2((-H2accys-S)]+ giving m/z 948 and the lost of two ammines was observed.   Keywords: thiolate, oligomers, 2D NMR, mass spectrometry
PREPARATION AND CHARACTERIZATION OF POROUS ALUMINA-TITANIA AEROGEL VIA CO2 SUPERCRITICAL EXTRACTION
Authors: Tursiloadi Silvester , Imai Hiroaki , Hirashima Hiroshi
Published: January 2019

Porous aerogel of titania-alumina were prepared by hydrolysis of metal alkoxides and supercritical extraction of the solvent.  Monolithic wet-gel of 0.2TiO2-0.8Al2O3, prepared by hydrolysis of metal alkoxides in alcoholic solutions, and the solvent in wet gel was supercritically extracted in CO2 at 60oC and 24Mpa for 2h. Thermal evolutions of the microstructure of the gel were evaluated by differential thermal analysis (TG-DTA), N2 adsorption, scanning electron microscopy and X-ray diffractometer. After calcination at 500oC, the specific surface area of the gel was more than 400m2g-1. The average pore radius of aerogel, about 8nm, was about 50% of that for alumina aerogel, but about 4 times larger than that of the xerogel.  The specific surface area of the aerogel was more than 200m2g-1 after calcination at 800oC. The pore size and pore volume of aerogel hardly decreased after calcinations at 800oC, although those values of the xerogel remarkably decreased after calcination up to 800oC. The thermal stability of the microstructure of porous titania-alumina is improved by supercritical extraction.   Keywords: Oxides, Sol-gel chemistry, X-ray diffraction, Infrared pectroscopy
DETERMINATION OF RATE CONSTANT AND STABILITY OF ADSORPTION IN COMPETITIVE ADSORPTION OF Cr(III) AND Cd(II) ON HUMIC ACID BY USING THE NEW MODEL OF KINETIC FORMULATION
Authors: Suyanta Suyanta , Sudiono Sri , Santosa Sri Juari
Published: January 2019

Determination of rate and stability constants of adsorption in competitive adsorption of Cr(III) and Cd(II) on humic acid by using the new model of kinetic formulation has been done. The new model based on assumption that those adsorption was first order adsorption rearched equilibrium. Humic acid was isolated from Peat moss of Silaut- West Sumatra by modificated Schnitzer method. Humic acid characterization was conducted by using infrared spectrophotometer with KBR pellet method. The experiment of kinetic adsorption was conducted in batch system reactor using erlenmeyer at 25 ± 0.01 oC of water steam bath and in a series of sampling procedure. Initial concentration of both Cr(III) and Cd(II) was 4x10-4 M. Thirty milligrams of humic acid was added to 200 mL of metal solution, and then stirred continuously. At the fixed periode of time, 10 mL of sample was taken using a syringe, then filterd with 0.45 µm filter paper. Concentration of Cr(III) and Cd(II) in the filtrate was determinated by AAS, while that was adsorbed by humic acid was equal to difference between initial and equilibrium concentration. It was concluded that competitive adsorption of Cr(III) and Cd(II) on humic acid was first order adsorption rearched equilibrium as proposed in this research. Adsorption rate constant of Cr(III) on humic acid  at competitive condition was greater than of Cd(II), but on the contrary for stability constant (K). Competition between Cr(III) and Cd(II) to interact with the active side of humic acid was dominated by Cr(III).   Keywords: rate constant, stability and competitive adsorption
REDUCTION AND OXIDATION PROCESSES OF CHROMIUM IN HUMIC ACID SUBFRACTION-SENSITIZED PHOTOCATALYST
Authors: Santoso Uripto Trisno , Herdiansyah Herdiansyah , Santosa Sri Juari , Siswanta Dwi
Published: January 2019

The process of reduction and oxidation of soluble chromium in humic acid subfraction-sensitized photocatalyst was studied. Humic acid was extracted from peat soil sampled in Gambut District, South Kalimantan. Humic acid (HA) was fractionated to humic acid subfraction (HAS) by centrifugation method. ZnO and TiO2 were applied as the photocatalysts produced by Merck, suspended in solution of 2 g/L. Two germicide UV lamps 30 watt (Philip®) was placed in a box at 20 cm above the samples. The results showed that HA or HAS sensitized the photoreduction of Cr(VI) by photocatalyst. The low molecular weight of HAS is more effective to act as sensitizer than the high molecular weight one. The yield of the photoreduction of Cr(VI) with photocatalysts enhanced both in the presence of Fe(II) ion and HAS. UV irradiation of the MnO4- solutions containing Cr(III) induced the photooxidation of Cr(III) to Cr(VI). The presence of Fe(III) or HAS doesn't inhibit significantly. The inhibition is enhanced by the present of both HAS and Fe(II) or HAS and Fe(III). This inhibition is enhanced more by the presence of ZnO or TiO2 photocalysts.   Keywords: reduction, oxidation, chromium, humic acid, photocatalyst
CORRELATION BETWEEN PREEXPONENTIAL FACTOR AND ACTIVATION ENERGY OF ISOAMYLALCOHOL HYDROGENOLYSIS ON PLATINUM CATALYSTS
Authors: Triyono Triyono
Published: January 2019

Arrhenius equation stated that reaction will proceed faster at higher temperature and with lower activation energy (Ea). Many literatures reported that preexponential factor (A) is constant for certain reaction and there is no relation between A and Ea. Experiment on the reaction of isoamylalcohol hydrogenolysis showed that logarithm of A increased linearly with Ea. The result of this investigation suggests that the rate of a process is affected by the number of active centers on the surface of a catalysts, which influences the value of the pre-exponential term in the expression for the rate constant of a reaction. An increase in the number of active centers corresponds to a higher value of A, the active centers would be less effective and is attended by a growth in the value of Ea. Therefore, reaction with lower activation energy will not always has higher reaction rate due to decreasing of Ea.   Keywords: isoamylalcohol hydrogenolysis, preexponential factor, activation  energy.
SUSCEPTIBILY OF Aeromonar hydrophylla BACTERIA ISOLATED FROM UNHEALTHY BAUNG FISH (Mystus nemurus) TOWARDS ANTIMICROBIAL AGENTS
Authors: Taufik Pipik , Bastiawan Dayat
Published: January 2019

The susceptibility of Aeromonas hydrophila isolated from ikan baung (Mystus nemurus) to antimicrobial agents was carried out. The objective of study is to know the kind of antimicrobial agents for the control aeromonasis  of Mystus nemurus. Tryptic soy agar (TSA) plate consisted 106 cells/plate of A. hydrophila on its surface was kept paper disk consisted antimicrobial agent, than incubated on 30 0C for 24 hours. The results showed that from 10 isolates to be tested, 5 isolates were resistant, 2 isolates were intermediate and 3 isolates were sensitive to tetracycline and chloramphenicol respectively; one isolate was resistant, 6 isolates were intermediate and 2 isolates were sensitive to nalidixic acid. Minimal in hibitory concentration (MIC) of tetracycline and chlorampenicol to the sensitive isolates were 0.5 ppm respectively.   Keywords: The susceptibility, Aeromonas hydrophila, antimicrobial agents
QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP ANALYSIS OF CURCUMIN AND ITS DERIVATIVES AS GST INHIBITORS BASED ON COMPUTATIONAL CHEMISTRY CALCULATION
Authors: Istyastono Enade Perdana , Martono Sudibyo , Pranowo Harno Dwi , Tahir Iqmal
Published: January 2019

The Quantitative Structure-Activity Relationship (QSAR) study was established on curcumin and its derivatives as glutathione S-transferase(s) (GSTs) inhibitors using atomic net charges as the descriptors. The charges were resulted by semiempirical AM1 and PM3 quantum-chemical calculations using computational chemistry approach. The inhibition activity was expressed as the concentration that gave 50% inhibition of GSTs activity (IC50). The selection of the best QSAR equation models was determined by multiple linear regression analysis. This research was related to the nature of GSTs as multifunctional enzymes, which play an important role in the detoxification of electrophilic compounds, the process of inflammation and the effectivity of anticancer compounds. The result showed that AM1 semiempirical method gave better descriptor for the construction of QSAR equation model than PM3 did. The best QSAR equation model was described by : log 1/IC50 = -2,238 - 17,326 qC2' + 1,876 qC4' + 9,200 qC6' The equation was significant at 95% level with statistical parameters : n = 10, m = 3, r­ = 0,839, SE = 0,254, F = 4,764, F/Ftable = 1,001.   Keywords: QSAR analysis, curcumin, glutathione S-transferase(s) (GSTs), atomic net charge
PREPARATION OF Ni-Mo/MORDENITE CATALYSTS UNDER THE VARIATION OF Mo/Ni RATIO AND THEIR CHARACTERIZATIONS FOR STEARIC ACID CONVERSION
Authors: Trisunaryanti Wega , Triyono Triyono , A Denty Fibirna
Published: January 2019

The preparation of Ni-Mo/Mordenite catalysts with variation of Mo/Ni ratio and their characterizations for conversion of stearic acid have been conducted. The catalysts were prepared by loading a small amount of nickel and/or molybdenum on H-Mordenite (H-Mor) with total metal content = 1 wt% based on the mordenite. The metals was supported on to the mordenite by impregnation method using nickel nitrate and/or ammonium heptamolybdate solution. The Mo/Ni ratio was varied as follows 0/1, 1/0, 1/1, 2/1, and 3/1 produced Ni/Mor, Mo/Mor, Ni1-Mo1/Mor, Ni1-Mo2/Mor and Ni1-Mo3/Mor catalyst respectively. The catalysts were then calcinated with nitrogen, oxidized with oxygen and reduced by hydrogen. The characterizations of catalyst were carried out by measuring Ni and Mo contents using atomic absorbtion spectroscopy (AAS), acidity by ammonia vapour adsorption, specific surface area and pore size distribution by nitrogen gas adsorption (NOVA-1000). The catalyst characters on conversion of stearic acid were performed in a flow reaction system at 4000C under hydrogen stream (10 mL/min). The AAS analyses showed that the metal impregnated on to the H-Mor sample were consistent to the initial metal concentrations. The loading of Ni and/or Mo enhanced the acidity, however decreased the specific surface area and total pore volume of the H-Mor sample. The higher the acidity the higher the conversion of stearic acid and the lower the coke formation. The other catalyst characters gave the variation effects toward the stearic acid conversion. The conversions of stearic acid were 34,52%,  43,33%, 65,10%, 80,10%, 86,42% and 95,72% produced by Ni1-Mo3/Mor, H-Mor, Mo/Mor, Ni/Mor, Ni1-Mo2/Mor and Ni1-Mo1/Mor catalyst, respectively.   Keywords: Ni-Mo/Mordenite, impregnation, stearic acid, Ni1-Mo1/Mordenite
STUDY OF DOUBLE PROTONS MIGRATION MECHANISM IN SUPRAMOLECULAR STRUCTURES OF ACETIC ACID-WATER AND ACETIC ACID-AMMONIA BY AB INITIO METHOD
Authors: Wijaya Karna , Tahir Iqmal , Harnowo Harnowo
Published: January 2019

The theoretical study of double protons migration mechanism on acetic acid-water and acetic acid-ammonia associations has been carried out. The research covered determinations the reactant, transition state and product structures. To gain the goal, the research was conducted in three steps, i.e. (i) designing the reactant, transition state and product models, (ii) optimizing of structures, and (iii) calculating of their uncorrected total energy and frequencies with ab initio methods (basis set 6-31G**). All calculations were performed using Hyperchem ver 5.0 for Windows and Gaussian 94W package program. The computational study result showed that the calculated structures were in good agreement with the hypothetical structures.   Keywords: double protons migration, acetic acid, water, ammonia, molecular mechanics and ab-initio
THEORETICAL STUDY OF THE EFFECT OF WATER MOLECULE ADDITION ON THE CONFORMATION OF SUBSTITUTED DIBENZO-18-CROWN-6 ETHER IN ITS COMPLEXATION WITH Na+ CATION USING SEMI EMPIRICAL METHOD MNDO/d
Authors: Pranowo Harno Dwi , Siregar Tuti Hartati , Mudasir Mudasir
Published: January 2019

The effect of water molecule addition into modeling structure of complex of substituted dibenzo-18-crown-6 ether with metal ion Na+ was studied. The aim of this research is to find information about geometrical conformation of substituted DB18C6 and its selectivity to complex/coordinate metal ion Na+ in the presence of water molecule. In this research semi empirical method was used for calculation. To find the best conformation, trial and error experiments were conducted using semi empirical method available in HyperChem 6.0, finally MNDO/d method was selected. The result of geometry optimization showed that addition of water molecule improve the stability of the conformation of substituted DB18C6 and increase the selectivity of this compound to complex metal ion Na+. The presence of electron-withdrawing substituents decreased the binding energy while that of electron-donating one increase the binding energy (value of DE more negative). Cavity radii of DB18C6 in the presence of water molecule extended from 2.3 Å to 2.6 Å. This figure is almost similar to that of experimental data.   Keywords: Crown ether, molecular modelling, semiempirical method
QUANTITATIVE STRUCTURE AND ACTIVITY RELATIONSHIP ANALYSIS OF 1,2,4-THIADIAZOLINE FUNGICIDES BASED ON MOLECULAR STRUCTURE CALCULATED BY AM1 METHOD
Authors: Mudasir Mudasir , Tahir Iqmal , Putri Ida Puji Astuti Maryono
Published: January 2019

Quantitative structure-Activity relationship (QSAR) analysis of fungicides having 1,2,4-thiadiazoline structure based on theoretical molecular properties have been done. Calculation of the properties was conducted by semiempirical method AM1 and the activity of the compounds was taken from literature. Relationship analysis between fungicides activity (pEC50) and molecular properties was done using SPSS program. The QSAR analysis gave the best model as follows: pEC50 = 3.842 + (1.807x10-4) ET + (5.841x10-3) Eb - (5.689x10-2) DHf  -0.770 log P + 1.144 a - 0.671 m + 9.568 GLOB - (5.54x10-2) MR. n=19   r=0.917   SE=0.216   Fcal/Ftable=2.459   PRESS=0.469. The best model obtained was then used to design and predict the fungicides activity of new compounds derived from 1,2,4-thiadiazoline.   Keywords: QSAR, QSPR, fungicide, molecular structure, 1,2,4-thiadiazoline
MULTIFUNCTION OF LAYERED AND POROUS MATERIALS
Authors: Wijaya Karna
Published: January 2019

In this review, two sort of materials i.e layered and porous materias which were studied by the author and coworkers intensively and extensively  will be described. These materials generally can be classified into two groups, namely layered organic and inorganic materials and porous organic and inorganic materials. To the materials which classified in the first group, it will be discussed the syntheses, characterization and application of layered organic materials of imidazolium-dimesylamidate and of layered inorganic materials of montmorillonite. For the second group, as examples we will analogically describe the syntheses, characterization and application of 2,6-dimethylpyridinium-di(methanesulfonyl)amidate porous organic material and zeolite and pillared clay porous inorganic materials.   Keywords: layered materials, porous materials, syntheses, characterization, application.
EXPLOITING A BENEFIT OF COCONUT MILK SKIM IN COCONUT OIL PROCESS AS NATA DE COCO SUBSTRATE
Authors: Setiaji Bambang , Setyopratiwi Ani , Cahyandaru Nahar
Published: January 2019

A research to know influence of mixing concentration of coconut water and sucrose concentration to coconut milk skim as nata de coco substrate has been conducted. The variation was taken from mixing coconut water (0%, 25%, 35% and 50% and 100% as control) and the sucrose concentration (0.5%, 1%, 1.5% and 2%). Coconut milk skim boiled before used as substrat, yielded a coconut protein (blondo). The result of research showed that coconut milk skim can be used as nata de coco substrate with mixing coconut water and sucrose addition, mixing 50 % concentration coconut water representing optimum concentration. The content of crude fibre nata was yielded by higher concentration of sucrose, while mixing concentration coconut water do not influence crude fibre content.   Keyword: Coconut milk skim, substrate, nata de coco
CHARACTERIZATION OF MODIFIED BENTONITE USING ALUMINUM POLYCATION
Authors: Haerudin Hery , Rinaldi Nino , Fisli Adel
Published: January 2019

The modification of bentonite by pillarization using aluminum polycation type Keggin [Al13O4(OH)24(H2O)12]7+ has been carried out, by exchange of cation from interlayer with aluminum polycation. The amount of aluminum polycation, which was used for the pillaring of bentonite was varied, i.e. 5 mmol/gram, 10 mmol/gram, and 20 mmol/gram of bentonite. After drying, the pillared bentonite was calcined at 400 oC for 6 hour with temperature rate of 5 oC/min. The cationic exchange capacity (CEC) of starting bentonite was 98.3 meq/100 gram. The concentration ratio of Al/Si increased from 0.27 to 0.34 for pillared bentonite and of Ca/Si was decreased from 0.06 to 0.006 for pillared bentonite. The basal space for pillared bentonit increased significantly from 7.30 Å to about 18 Å . The measured specific surface area (by BET) of pillared bentonite was also increased significantly from 46 m2/g to about 162 m2/g. It was concluded that bentonite has been pillared by aluminum polication successfully.   Keywords: aluminum polycation, bentonite
QSAR STUDY OF 1,10-PHENANTHROLINE DERIVATIVES AS THE ANTIMALARIAL COMPOUNDS USING ELECTRONIC DESCRIPTORS BASED ON SEMIEMPIRICAL AM1 CALCULATION
Authors: Mustofa Mustofa , Tahir Iqmal , Jumina Jumina
Published: January 2019

Quantitative Structure-Activity Relationship (QSAR) analysis of 1,10-phenantroline analogs as antimalarial drug has been conducted using atomic net charges (q) as predictors of their activity. Data of predictors are obtained from computational chemistry method using semi-empirical molecular orbital AM1 calculation. Antimalarial activities are taken as the activity of the drugs against plasmodium falciparum (FcM29-Cameroun) strain and are presented as the value of ln(1/IC50) where IC50 is an effective concentration inhibiting 50 % of the parasite growth.  The results show that there is correlation between antiplasmodial activity and electronic structure as represented by a linear function of activity versus atomic net charges of N1, C7, C10, C14 atoms on the 1,10-phenanthroline skeleton and is expressed by : log IC50 = -3,4398 - 14,9050 qN1 - 8,5589 qC10 - 14,7565 qC7 + 5,0457 qC11 The equation is significant at 95% level with statistical parameters : n = 13; r = 0,96275; r2 = 0,92689; SE = 0,61578 and F (4,8) = 25,3556.   Keywords: antimalarial drug; 1,10-phenanthroline; QSAR; antiplasmodial activity.
EFFECT OF DIATOMEAOUS EARTH TREATMENT USING HYDROGEN CHLORIDE AND SULFURIC ACID ON KINETICS OF CADMIUM(II) ADSORPTION
Authors: Nuryono Nuryono , Narsito Narsito
Published: January 2019

In this research, treatment of diatomaceous earth, Sangiran, Central Java using hydrogen chloride (HCl) and sulfuric acid (H2SO4) on kinetics of Cd(II) adsorption in aqueous solution has been carried out. The work was conducted by mixing an amount of grounded diatomaceous earth (200 mesh in size) with HCl or H2SO4 solution in various concentrations for two hours at temperature range of 100 - 150oC. The mixture was then filtered and washed with water until the filtrate pH is approximately 7 and then the residue was dried for four hours at a temperature of 70oC. The product was used as an adsorbent to adsorb Cd(II) in aqueous solution with various concentrations. The Cd(II) adsorbed was determined by analyzing the rest of Cd(II) in the solution using atomic absorption spectrophotometry. The effect of treatment was evaluated from kinetic parameter of adsorption rate constant calculated based on the simple kinetic model. Results showed  that before equilibrium condition reached, adsorpstion of Cd(II) occurred through two steps, i.e. a step tends to follow a reaction of irreversible first order  (step I) followed by reaction of reversible first order (step II). Treatment with acids, either hydrogen chloride or sulfuric acid, decreased adsorption rate constant for the step I from 15.2/min to a range of 6.4 - 9.4/min.  However, increasing concentration of acid (in a range of concentration investigated) did not give significant and constant change of adsorption rate constant. For step II process,  adsorption involved physical interaction with the sufficient low adsorption energy (in a range of 311.3 - 1001 J/mol).     Keywords: adsorption, cdmium, diatomaceous earth, kinetics.
THERMAL EFFECT OF COCONUT CREAMS ABILITY TO ADSORB CALCIUM(II)
Authors: Tahir Fatmawati , Setyopratiwi Ani , Sudiono Sri
Published: January 2019

Study of thermal effect of coconut cream's ability to adsorb Ca (II) has been done at various temperatures of 49 oC,  59 oC and 80 oC. The adsorption study was performed to check capacity, energy and rate of adsorption by varying the number of initial concentration of CaCl2 bounded on coconut protein. This research was also done to determine number of Ca (II) in the coconut protein using the salt addition and elicits reaction methods. The result showed that adsorption ability tends to increased with the increase of temperature). Coconut cream heated at 59 oC adsorb Ca(II) with the highest adsorption capacity of 3.98 mg/g and K = 3.48x104  mol-1. The salt addition method on the coconut cream gives more Ca (II) than elicit reaction method. The first method gives 0.01137 mol/L and the second was 0.02845 mol/L. Based on the energy of adsorption, cream without heating had 20.59 kJ/mol as a physical adsorption and heating effect at temperatures 49 oC, 59 oC and 80 oC had 24.95; 28.87 and 24.87 kJ/mol respectively as a chemical adsoprtion with the rate of adsorptions of 0,0054;  0,0510 dan  0,3. 10-4 minute-1, respectively.   Keywords: coconut cream, adsorption, thermal effect.
THE SYNTHESIS OF Cr2O3-PILLARED MONTMORILLONITE (CrPM) AND ITS USAGE FOR HOST MATERIAL OF p-NITROANILINE
Authors: Wijaya Karna , Tahir Iqmal , Baikuni Ahmad
Published: January 2019

The synthesis of Cr2O3-pillared montmorillonite (CrPM) and its usage for host material of p-nitroaniline have been conducted. The Cr2O3-pillared montmorillonite clays was prepared by a direct ion exchange method. First, the polyhydroxychromium as a pillaring spesies was intercalated into the interlayer region of the montmorillonite clays (purified clay in the monocation form), result in a montmorillonite-polyoxychromium intercalation compound. The precursors/pillaring spesies was not stable, hence it must be stabilized by calcination in order to transform the polyoxychromium via dehydration and dehydroxylation processes into Cr2O3. This oxide constituts the so-called pillar that prop the clay layers apart to a relatively large distance. The Cr2O3-pillared clays as a host material was added into ethanol solution saturated with p-nitroaniline, and mixture was stirred for 24 h at room temperature. The Na-montmorillonite, Cr2O3-pillared clay and p-nitroaniline-Cr2O3-pillared clay (pNA-CrPM) were characterized by X-Ray Diffraction (XRD), Gas Sorption Analysis, Infrared Spectroscopy (FTIR) and Activated Neutron Analysis (ANA) methods. The result of research showed that basal spacing (d001) of Cr2O3-pillared montmorillonite (CrPM) was 18,55 Å, meanwhile the basal spacing of the hydrated Na-montmorillonite was 14,43 Å. The specific surface area of the Cr2O3-pillared montmorillonite was 174,308 m2/g, whereas p-nitroaniline-Cr2O3-pillared clay (pNA-CrPM) was 133,331641 m2/g. This fact indicated that p-nitroaniline has been included into the pore of the Cr2O3-pillared clay.   Keyword: montmorillonite, pillared-clay, ion exchange, intercalate.
SYNTHESIS OF 3,4-DIMETHOXY ISOAMYL CINNAMIC AS THE SUNSCREEN COMPOUND FROM CLOVE OIL AND FUSEL OIL
Authors: Wahyuningsih Tutik Dwi , Raharjo Tri Joko , Tahir Iqmal
Published: January 2019

Synthesis of sunscreen compound 3,4-dimethoxy isoamyl cinnamic from clove oil and fusel oil has been done. The majoring component of clove oil that is eugenol has been isolated, followed with several chemical processes i.e. isomerization into isoeugenol, oxidation of the product to change into vanillin, then modification vanillin into veratraldehyde. From the fusel oil, we isolate isoamyl alcohol and modified by acetylation into isoamyl acetic. The final product could be produce by Claissen's condensation of isoamyl acetic and veratraldehyde to give 3,4-dimethoxy isoamyl cinnamic. All of the processes are followed with structure characterization using GC, IR, GC-MS and 1H-NMR spectroscopy. The result shown that compound has 46.98% purity and potent as the UV-B sunscreen's type (lmax = 313 nm). In-vitro sunscreen's activity of the compound was tested by UV-Vis spectrophotometry and resulting a maximum Sun Protection Factor value (SPFin-vitro) at low concentration, 10.25 mg/mL.   Keywords: UV absorber, sunscreen, clove oil, cinnamic esther.
A Kinetic Study of Aluminium(III) and Chromium(III) Adsorption by Silica Gel Chaetoceros calcitrans Biomass Immobilized on Silica Gel
Authors: Raya Indah , Narsito Narsito , Rusdiarso Bambang
Published: January 2019

The kinetics of aluminium(III) and chromium(III) adsorption in an adsorbent prepared by immobilization of Chaetoceros calcitrans biomass on silica ge has been investigated. The functional groups which were probable involved in the adsorption processes also identified. Experimentally, the adsorption was conducted by coloumn and batch method. In this work atomic adsorption spectrophotometric techniques was applied indirectly to determine of the metal ion adsorpted, and infra red spectroscopic technique was used for the identification of functional groups present in the adsorbent. The study included two parts of experiment, i.e. 1) the determination of rate of adsorption and 2) the determination of capacity and energy of adsorption. Results showed that the AI(III) and Cr(III) adsorption data fit quiet well with non linear kinetics model proposed by Langmuir-Hinshelwood giving a first order rate constant, (k1) of 8.65.10-3 min-1 for AI(III) and 9.92.10-4 min' for Cr(III) when the immobilized biomass used as the adsorbent in agreement with the activation energy calculation giving values of 1.184 kcal/mole for Al(111) and 1.877 kcal/mole for Cr (Ill). It was concluded that the adsorption of Al(III) and Cr(III) on Chaetoceros calcitrans immobilized and free Chaetoceros calcitrans adsorbents, may be classified as chemical adsorption, involving entalphi of adsorption in the range of 6-17 kcal/mole. And the infra red spectroscopic data indicated that the functional groups i.e.: carboxylate (-COO), hydroxyl (-OH) silanol (SI-OH), siloksil (SI-O-Si) and amine (NH2) are present in free Chaetoceros calcitrans biomass and silanol (Si-OH), siloksil (Si-O-Si), hydroxyl (-OH)and C-H metilene (-CH2) are present in immobilized biomass Chatoceros calcitrans, while only siloksil (Si-O-Si) and silanol (Si-OH) in silica gel.
The Blending of EPDM/NR with Maleic Anhydride as Compatibilizer: Comparing the Effect of Accelerators on Cure Characteristic and Mechanical Properties
Authors: Mayasari Hesty Eka , Setyorini Ike , Yuniari Arum
Published: January 2019

The blending of ethylene propylene diene monomer/natural rubber (EPDM/NR) needs much attention because of their incompatibility. In this work, the influence of accelerator type on cure characteristics and mechanical properties of 60/40 EPDM/NR blend was investigated. The compounds were prepared by controlling the migration of curative and using maleic anhydride as the compatibilizer. Three types of accelerators were studied: 2,2-dithiobis(benzothiazole) (MBTS), the combination of MBTS and tetramethyl thiuram disulfide (TMTD), and n-tert-butyl-2-benzothiazolesulfenamide (TBBS). The cure characteristic, mechanical properties, and morphology of the composites had been investigated by rheometer, tensile testing machine, hardness durometer and scanning electron microscope (SEM). Blending of EPDM/NR with various accelerator gave different composite characteristics. MBTS, used in single or binary accelerator system, provided good mechanical properties. TBBS gave the longest scorch time, the lowest crosslink density and poor mechanical properties, except tear strength. Binary accelerator, MBTS/TMTD, provided the lowest processing time and the highest cure rate, but not significantly different from MBTS. Binary accelerator gives the best aging resistance and compatibility blend. These results correspond well with SEM micrograph. From the study, it can be concluded that binary accelerator system was the proper accelerator for EPDM/NR blend.
Superparamagnetic Nanocomposite of Magnetite-Chitosan Using Oleic Acid as Anti Agglomeration and Glutaraldehyde as Crosslinkage Agent
Authors: Suyanta Suyanta , Sutarno Sutarno , Nuryono Nuryono , Rusdiarso Bambang , Kunarti Eko Sri , Kusumastuti Hesti , Kurnia Lia
Published: January 2019

In this research magnetite was synthesized by coprecipitation method, in which solution of NH4OH was added into the solution containing a mixture of Fe2+/Fe3+ (molar ratio 1:2) until pH 11 under strong ultrasonic agitation for 30 min. The black sediment of magnetite was filtered, washed and dried. The product was then modified by using oleic acid to prevent agglomeration. Chitosan was prepared by deacetilization of chitin, whereas chitin was extracted from shrimp shell. In the synthesis of nanocomposite, 0.5 g of chitosan and 1.5 g of oleic acid modified magnetite were introduced into 100 mL of 2% acetic acid solution, followed by sonication treatment for 10 min and magnetic stirring for 20 min. In order to perform the cross-linkage reaction, solution of 2% glutaraldehyde was added into the mixture at temperature of 40 °C for 3 h. The composite was collected by magnetic separation, followed by washing with distilled water and ethanol in a row. The product was dried and characterized by XRD, FTIR, TEM and VSM methods. The result showed that the composite had good crystal structure with a cubic inverse spinel structure, monodisperse and quasi sphere in shape with diameter of 20–25 nm. It had high saturation magnetization (43.4 emu/g) and superparamagnetic property.
Grafting of Heparin on Blend Membrane of Citric Acid Crosslinked Chitosan/Polyethylene Glycol-Poly Vinyl Alcohol (PVA-PEG)
Authors: Lusiana Retno Ariadi , Pambudi Ginanjar Argo , Sari Fitra Nilla , Widodo Didik Setiyo , Khabibi Khabibi , Isdadiyanto Sri
Published: January 2019

Heparin, an active sulfate group material, grafted onto blend membrane citric acid cross-linked chitosan/poly (vinyl alcohol)-poly(ethylene glycol) (PVA-PEG) to improve the membrane properties. The physical tests shown that grafting reaction of citric acid crosslinked chitosan increased the mechanical strength and membrane swelling. The permeability test results, it was found that the grafted chitosan membrane was improved permeability of both urea and creatinine as compared to chitosan pure and chitosan crosslinked membrane. The negative charge of the sulphonate group of heparin increased the number of the active side of the carrier in the membrane, which then correlated to the membrane’s permeability process.
Sorption Mechanism and Performance of Peat Soil Humin for Methylene Blue and p-Nitrophenol
Authors: Santosa Sri Juari , Kunarti Eko Sri , Aprilita Nurul Hidayat , Wulandari Beti , Bawani Dhian Nuri
Published: January 2019

The responsible mechanism and performance of peat soil humin for the sorption of methylene blue (MB) and p-nitrophenol (p-NP) have been investigated. Humin was obtained from peat soil of Siantan, West Kalimantan, Indonesia, after removing the content of humic and fulvic acids into a NaOH solution using the recommended procedure of International Humic Substances Society (IHSS). The obtained humin was then purified by rigorous stirring in a mixed solution of HCl 0.1 M and HF 0.3 M. Ash content in humin after the purification abruptly decreased from 36.84 to 1.26 wt.% indicating that minerals and other inorganic impurities were mostly removed. Phenolic –OH and carboxyl (–COOH) functional groups contributing to the acidity of humin were in the level of 3.44 and 2.10 mmol/g, respectively. At optimum medium pH of 6.20 for MB and 7.00 for p-NP, –COO– as the deprotonated product of –COOH was the most responsible active site in sorbing MB and p-NP through electrostatic interaction and hydrogen bonding, respectively. The homogeneity of –COO– as the active site for the sorption of MB and p-NP implied that the surface of humin sorbent was energetically uniform and thereby the sorption of both MB and p-NP followed better the Langmuir than the Freundlich isotherm model with sorption capacity of 0.19 and 0.26 mmol/g and sorption energy of 32.92 and 27.27 kJ/mol, respectively.
Comparison of Au(III) Sorption on Amine-Modified Silica (AMS) and Quaternary Amine-Modified Silica (QAMS): A Thermodynamic and Kinetics Study
Authors: Ngatijo Ngatijo , Basuki Rahmat , Nuryono Nuryono , Rusdiarso Bambang
Published: January 2019

Amine-Modified Silica (AMS) and Quaternary Amine-Modified Silica (QAMS) has been synthesized through the sol-gel process for adsorption Au(III) in aqueous solution. The aim of this work was to compare the effect of addition three methyl group of AMS to form QAMS on its character, thermodynamics and kinetics parameter of sorption of Au(III) in aqueous solution. Characterizations performed by FT-IR, XRD, SEM and BET analyzer. Sorption study was carried out in a batch system under the various experimental conditions including the effect of medium acidity, a variation of Au(III) concentration (thermodynamics study), and variation of contact time (kinetics study). Optimum pH of sorption Au(III) on AMS was 3 and shift into 5 on QAMS. Thermodynamics sorption study by Langmuir isotherm models indicates that there was an increase of sorption capacity from 37.94 mg/g (AMS) to 74.47 mg/g (QAMS). Kinetics sorption studies by Lagergren, Ho, and RBS models indicate that the sorption Au(III) in this research fitted well with the RBS models. The addition of 3 methyl group also increased the sorption rate of Au(III) on QAMS (ka = 77.29 min-1 (mole/L)-1) over AMS (ka = 69.22 min-1 (mole/L)-1) and reinforce the electrostatic interaction between active site of QAMS.
A Simple Pre-concentration Method for the Determination of Nickel(II) in Urine Samples Using UV-Vis Spectrophotometry and Flame Atomic Absorption Spectrometry Techniques
Authors: Khudhair Ahmed Fadhil , Hassan Mouyed Khudhair , Alesary Hasan F. , Abbas Ahmed S.
Published: January 2019

The cloud point technique was effectively utilized for extraction and pre-concentration of nickel(II) in urine samples before measurement by UV-Vis spectrophotometer and AAS techniques. The metal response to a para-aminophenol (PAP) reagent in a non-ionic surfactant Triton X-114 medium was to form the Ni-PAP complex. The adopted concentration for PAP, concentration of Triton X-114, pH effect and water bath temperature, incubation time, salt effect, and interference effects were all optimized. The calibration curve was linear over the range of (0.0625–1.25) mg L–1 with a correlation coefficient r2 of 0.9682 for the UV-Vis spectrophotometer at a λmax of 629 nm. The limit of detection was 0.005 mg/L. The relative standard deviation for six replicates was 1.07%. This method was applied successfully to determine copper (II) concentrations in 44 urine samples of occupational worker samples as determined by UV-Vis spectrophotometry and FAAS techniques.
Preparation and Characterization of a Novel Cocrystal of Atorvastatin Calcium with Succinic Acid Coformer
Authors: Wicaksono Yudi , Setyawan Dwi , Siswandono Siswandono , Siswoyo Tri Agus
Published: January 2019

Preparation and characterization of a novel cocrystal of atorvastatin calcium with succinic acid coformer were successfully performed. This research aims to modify the crystalline form of atorvastatin calcium through cocrystallization with succinic acid coformer. The cocrystal was prepared by a solvent evaporation method and characterized by Powder X-Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The atorvastatin calcium-succinic acid cocrystal has new crystalline peaks at 2θ of 12.9, 18.2 and 26.7° indicating the formation of a new crystalline phase. The cocrystal showed the melting point at 205.7 °C with an enthalpy of fusion 30.2 J/g which is different from the initial components. The FTIR spectra of cocrystal showed the shifting of absorption peaks of groups of initial components indicating of formation of atorvastatin calcium-succinic acid cocrystal through acid–amide intermolecular hydrogen bond interactions. The solubility and dissolution test showed that the cocrystal has solubility and dissolution rate significantly higher than the solubility and dissolution rate of pure atorvastatin calcium.
Effect of Temperature, Time and Diimide/Rubber Ratio on the Hydrogenation of Liquid Natural Rubber by Response Surface Methodology
Authors: Idris Mohamad Shahrul Fizree , Azhar Nur Hanis Adila , Firdaus Fazira , Ashari Siti Efliza , Yusoff Siti Fairus Mohd
Published: January 2019

Hydrogenated liquid natural rubber (HLNR) was synthesized from liquid natural rubber (LNR) by thermolysis of p-toluenesulfonyl hydrazide (TSH). The HLNR structure was characterized by Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Thermogravimetric analysis (TGA) showed that the HLNR had higher decomposition temperature compared to LNR. A response surface methodology (RSM) based on a central composite rotatable design (CCRD) with five-level-three-factors was used to optimize the main important reaction parameters, such as the TSH:LNR weight ratio (1–3), reaction temperature (110–150 °C), and reaction time (1–8 h). A quadratic model was developed using this multivariate statistical analysis. Optimum conditions for the non-catalytic hydrogenation of LNR using TSH were obtained; an LNR hydrogenation percentage of 83.47% at a TSH:LNR weight ratio of 1.41, a reaction temperature of 118.11 °C, and a reaction time of 3.84 h were predicted. The R2 value of 0.9949 indicates that the model provides data that are well matched with those from the experiment.
KEBIJAKSANAAN PENGEMBANGAN SUMBER DAYA MANUSIA MENGHADAPI ERA TINGGAL LANDAS
Authors: Effendi Sofian
Published: January 2019

Human resources are a very important factor in their role to the development of many developing countries such as Indonesia. The development of human resources should be carefully planned by paying attention to the needs of its social structure as well as its national technology. For this reason, it needs appropriate relied strategy to be able the industrial community to prepare it self thoroughly during the present take-off stage era. One of its strategy is by identifying the problems which would possibly take place around the take-off stage, both domestic as well as foreign. The shift of the world economic structure that happened as a consequence of the development of new technology, and the slackening of the cold war between two very powerful countries are two most essential questions among the foreign problems; whereas the obstacles that come from the country itself are among others the extremely low labour productivity of Indonesia as a consequence of the poor educational level of the majority of the population, the low wages, the serious problems of unemployment,the inappropriate work ethics and work disciplines, and its inability inworld competition.Eased on the above statements, the most important effort to obtain potential human resources during the coming take-off stage era is by improving the quantity and quality of resources to be able to answer every challenge that may emerge later, and by putting high priority on the overall reorganization of human resources of Indonesiato become one of much stronger integrity.
NORMA-NORMA DAN PERILAKU SEKS REMAJA
Authors: Singarimbun Masri
Published: January 2019

This article contains further analysis of a comparative study on adolecent reproductive health in four areas: urban and rural Yogyakarta, and urban (Denpasar) and rural Bali. Questions were asked on the attitudes and practice regarding premaritalintercourse, contraception and induced abortion. There were noticeable diffrentials by sex and area. Female respondents have much less sexual experince than male respondents, whereas rural respondents have less sexual experience than urban ones. With regard to attitudes on premarital intercource and induced abortion, Balinese respondents were more permissive than the Javanese. As a matter off act rural Balinese were more permissive than (urban) Yogyakarta respondents.
PENGGUNAAN HASIL SENSUS UNTUK ESTIMASI URBANISASI
Authors: Darwin Muhadjir , Tukiran Tukiran
Published: January 2019

Urbanization canbedefined inmanyways: various definitions concerning it are found in population literature. Different censuses also tend to define the concept of urban differently. This inconsistency of definitionhas obstructed those who want to conduct acomparative analysis on urbanization, both cross- country and longitudinal analysis of a country. This article attempts to examine the problem by clarifying the definition of the concept and indicators of urban and urbanization and by making a longitudinal analysis of urbanization using the Indonesian 1920-1990 Cencus data. Regardless of how the concept of urban is defined in each census, this analysis has found a steady increase in urban population number. However, if the different definitions of the concept are taken into consideration, it may bring up different conclusion. Part of the reasons of the increase is a reclassification of village' status from being rural to become urban. Oneway to prove this proposition is by comparing the level of urban population growth between large cities and their surrounding regencies. This analysis clearly shows that the latter has higher population growth than the former.
NORMA-NORMA BESARNYA KELUARGA
Authors: Singarimbun Masri
Published: January 2019

Sesuai dengan naskah aslinya, tulisan belum dilengkapi dengan abstraksi.
KEBIJAKSANAAN KEPENDUDUKAN: TEORI, KONSEP, DAN PENERAPANNYA DI INDONESIA
Authors: Effendi Tadjuddin Noer
Published: January 2019

This paper discusses the theoritical, conceptual background of population policy in Indonesia. In particular, it discusses the theory that related to the population control especially the fertility and mortality. It also suggests that fertility can be reduced by implementing family planningprogram and to reduce infant mortality. The populationproblems notonly government care,but also public responsibility in order to save the environment for the next generation.