bluuebunny/crossref_metadata_2025_split huggingface dataset:
EFFECTS OF ETHYLENE GLYCOL AND KOH IN THE FORMATION OF 2-METHOXY-4-PROPYLPHENOL ON EUGENOL ISOMERIZATION REACTION
Authors: Muchalal Muchalal 
Published: January 2019

Formation reaction mechanism of 2-methoxy-4-propylphenol on eugenol isomerization that involved protic hydrogen originated from ethylene glycol as a solvent has been done. To check this reaction mechanism, the effect of amounts of ethylene glycol as a solvent and KOH as a reagent on the quantity of 2-methoxy-4-propylphenol as a product has been carried out. The reaction product was analyzed by GC and GC-MS. Quantity of 2-methoxy-4-propylphenol as a product increased if ratio of quantity of ethylene glycol as solvent to quantity of KOH as reagent became larger. The result showed that formation process of 2-methoxy-4-propylphenol involved the protic hydrogen of solvent. The existence of cis-isoeugenol as an initiator compound in forming 2-methoxy-4-propylphenol indicated that the reaction mechanism followed the steps (1) cis-isoeugenolic ion gave Cb with negative charge at prophenyl group through resonance (2) a negative charge Cb then attacked a protic H atom in the solvent, and (3) hydride ion will attack Cb to form 2-methoxy-4-propylphenolic ion . Keywords: 2-methoxy-4-propylphenol, ethyleneglycol - KOH.
STUDY OF LYSINE AND ALANINE DELIVERANCE THROUGH POLYPYRROLE MEMBRANE
Authors: Suratman Adhitasari , Buchari Buchari , Noviandri Indra , Gandasasmita Suryo 
Published: January 2019

Electropolymerization processes of pyrrole and the usage of polypyrrole membrane as lysine and alanine deliverance have been studied by cyclic voltammetry technique. Polypyrrole membrane was prepared by electropolymerization processes of pyrrole in water based solvent containing sodium perchlorate as supporting electrolyte. Electropolymerization processes were carried out within potential range of 0-1100 mV vs Ag/AgCl reference electrode and at the scanning rate of 100 mV/s. In this study, lysine and alanine have been used as molecules which could easily be loaded on and released from polypyrrole membrane. The presence of lysine or alanine during electropolymerization process reduced the rate of electropolymerization of polypyrrole. In lysine or alanine transfer processes into polypyrrole membrane, the interaction between polypyrrole and lysine or alanine showed by the curve of E½ oxidation in respect of - log C. It proved that the E½ oxidation shifted to more positive potential showed by the increasing of concentration of lysine or alanine. Beside that, voltammetric responses of lysine and alanine transfered into polypyrrole membrane were found to be Nernstian. The results indicated that polypyrrole could be used as a sensor of lysine and alanine. Keywords: Electropolymerization, polypyrrole membrane, voltammetry technique
RELATION OF ELECTRONIC STRUCTURES WITH THEIR ANTIMALARIAL ACTIVITIES ON ARTEMISININ DERIVATIVES
Authors: Armunanto Ria , Sudiono Sri 
Published: January 2019

Relation of electronic structures with their anti malaria activities on artemisinin derivatives was evaluated by means of quantitative structure activity relationship (QSAR) method. To describe electronic structures, atomic charges and dipol moments calculated by quantum mechanics on PM3 semiempirical level. A linear relation between activities and electronic structures was used to construct linear equation models. An equation model showing a good statistically criteria and a realibility of antimalarial activity was chosen to be used to design a compound with new activities against P. facilparum. Results show that 13 equation models were obtained, showing only three models with a good criteria. O2 and C4 atoms were observed for a key role of an improvement of the antimalarial activity. Keywords: artemisinin, antimalaria, atomic charge, dipole moment, PM3
SYNTHESIS OF ANTIMALARIAL 3-(2-HYDROXYETHYL)-2-METHYL-1,10-PHENANTHROLINE-4-OL FROM 8-AMINOQUINOLINE
Authors: Hadanu Ruslin , Anwar Chairil , Jumina Jumina , Tahir Iqmal , Mustofa Mustofa 
Published: January 2019

It has been conducted the synthesis of 3-(2-hydroxyethyl)-2-methyl-1,10-phenanthroline-4-ol was carried out from 8-aminoquinoline which are expected to posses antimalarial activity. The experiment perfomed consisted of two steps i.e (1) reaction of 8-aminoquinoline with 2-acetyl-butyrolactone and (2) cyclization of the resulted 3-[1-(quinolin-8-ylamino)-ethylidene]-4,5-dihydro-furan-2-one. The reaction of 8-aminoquinoline with 2-acetyl-butyrolactone was performed in toluene at reflux for 6 hours in the presence of p-toluensulfonic acid as catalyst. This reaction gave 3-[1-(quinolin-8-ilamino)-etiliden]-4,5-dihidro-furan-2-on in 60.6% yield. The cyclization of 3-[1-(quinoline-8-ylamino)-ethyliden]-4,5-dihydro-furan-2-one was conducted in cloroform at reflux for 4 hours in the presence of H2SO4 as catalyst and also tween 80 as transfer phase catalyst to give 3-(2-hydroxy-ethyl)-2-methyl-1,10-phenanthroline-4-ol in 76.2% yield. Identification of the products were carried out by means of infra red (IR) spectroscopy, proton nuclear magnetic resonance (1H-NMR) spectroscopy, and mass spectroscopy (MS). Keywords: antimalarial, 8-aminoquinoline, cyclization, 1,10-phenantroline
THE STABILIZING OF ANATASE AEROGEL AT HIGH TEMPERATURE
Authors: Tursiloadi Silvester , Hirashima Hiroshi 
Published: January 2019

Stable anatase is attractive to its notable functions for photo catalysis and photon-electron transfer. Stable anatase TiO­2 containing amorphous SiO2 aerogel was prepared by hydrolysis of Ti (OC3H7)4 and Si (OC3H7)4 in a 2-propanol solution with acid catalyst. The solvent in wet gels was supercritically extracted in CO2 at 60 oC and 22 Mpa. Thermal evolutions of the microstructure of the gels were evaluated by TGA-DTA, N2 adsorption and XRD. A stable anatase TiO2 containing amorphous SiO2 aerogel with a BET specific surface area of 365 m2/g and a total pore volume of 0.20 cm3/g was obtained as prepared condition. The anatase phase was stable after calcination up to 1000 oC, and BET specific surface area, total pore volume and average pore diameter did not change significantly after calcination up to 900 oC. Keywords: Supercritical extraction, sol-gel, aerogel, stable anatase structure
STUDY OF ELECTROPOLIMERIZATION PROCESSES OF PYRROLE BY CYCLIC VOLTAMMETRIC TECHNIQUE
Authors: Suratman Adhitasari , Buchari Buchari , Noviandri Indra , Gandasasmita Suryo 
Published: January 2019

Electropolymerization processes and electrochemical properties of polypyrrole as electroactive polymer have been studied by cyclic voltammetric technique. Pyrrole was electropolymerized to form polypyrrole in water-based solvent containing sodium perchlorate as supporting electrolyte in several pH values. The pH of the solutions were varied by using Britton Robinson buffer. The results showed that oxidation potential limit of electropolymerization processes of pyrrole was 1220 mV vs Ag/AgCl reference electrode. It can be seen that cyclic voltammetric respon of polypyrrole membrane that was prepared by electropolymerization processes of pyrrole at the scanning rate of 100 mV/s was stable. While the processes of pyrrole electropolymerization carried out at the variation of pH showed that the best condition was at the pH range of 2 - 6. Keywords: polypyrolle, electropolymer, voltammetric technique
A STUDY ON INTERACTION OF Cd(II) AND DIATOMACEOUS EARTH IN ADSORPTION PROCESS
Authors: Nuryono Nuryono , Suyanta Suyanta 
Published: January 2019

In this research, interaction occurring in adsorption process between Cd(II) and active site of diatomaceous earth has been studied. The study was carried out by evaluating Cd(II) adsorption on diatomaceous earth at various pHs, either for the earths without treatment, those after being heated or those treated with sulfuric acid and hydrogen chloride. Adsorption was performed by mixing diatomaceous earth, without and with treatments, and Cd(II) solution for one hour at various pHs (2 - 7), and un-adsorbed metallic ion was analyzed by atomic absorption spectroscopy (AAS). The treatments of diatomaceous earth included heating at temperatures of 300, 500, and 900oC for four hours, treatments with acids (3, 8, and 12 M of H2SO4, and 3, 15, and 18 M of HCl solutions for two hours at 150-200oC). Results showed that the increasing of pH from 2.0 to 3.0 and from 6.0 to 7.0 inclined adsorption of Cd(II) from 13.2 to 23.3 mg/g and from 24.0 to 26.4 mg/g, respectively. At a pH range of 3.0 - 6.0 the adsorption slightly increase from 23.3 to 24.0 mg/g. Heating of diatomaceous earth higher than 500oC caused the adsorption capability to be independence of the pH of solution. On the other hand, treatments with acids (H2SO4 and HCl) caused adsorption capability increased significantly with the increase in pH from 3.0 to 6.0. Adsorption evaluation at the pH range investigated showed that adsorption of Cd(II) on diatomaceous earth may be through interaction between Cd2+ and functional groups of T-OH (T = Si/Al). Keywords: adsorption, adsorbent, cadmium, diatomaceous earth
DEVELOPING METHOD OF DIFFERENTIAL PULSE POLAROGRAPHIC FOR ANALYSIS OF CHLORAMPHENICOL RESIDUE IN MILK
Authors: Tjahjono Daryono Hadi , Musadad Amir , K Septy Mariana 
Published: January 2019

A differential pulse polarographic method for a quantitative analysis of chloramphenicol residue in milk had been developed. Result showed that the method using dropping mercury electrode as working electrode, Ag/AgCl electrode as reference electrode, and platinum electrode as auxiliary electrode with an acetic buffer solution of pH 4.7 as supporting electrolyte had a recovery for chloramphenicol of (96.88 ± 3.17)% with a detection limit of 0,027 µg/mL, a quantitation limit of 0,089 µg/mL, and a determination limit of 0,010 µg/mL. Keywords: differential pulse polarography, residue, chloramphenicol, milk
ISOLATION AND STRUCTURE DETERMINATION OF BISDEMTHYLAAPTAMINE FROM BUNAKEN MARINE PARK SPONGE <i>Aaptos, sp.</i>
Authors: Rombang Wilson AR , Rumampuk Rymond J , Tarigan Ponis , Herlt Anthony J , Mander Lewis N 
Published: January 2019

Bisdemethylaaptamine, an alkaloid naphtyridine with molecular weight 200 and formulae molecule C11H8N2O2 has been isolated from Bunaken Marine Park sponge Aaptos sp. Isolation was done by using several stages of column chromatography and high performance liquid chromatography. Molecular weight of this naphtyridine alkaloid was determined by electron ionization (EI) and electrospray ionization (ESI) mass spectroscopies and its structure assigned to be 8,9-dihydroxy-1H-benzo[d,e][1,6]naphtyridine by proton and carbon nuclear magnetic resonances (1H and 13C-NMR). Keywords: Sponge, Aaptos sp., naphtyridine alkaloid, bisdemethylaaptamin
ADSORPTION OF Cr(VI) ON BLACK WATER
Authors: Januarita Rasti , Herdiansyah Herdiansyah 
Published: January 2019

The effect of initial concentration of Cr(VI) on adsorption to black water of Gambut, District of Banjar, South Borneo has been investigated, as well as interaction between Cr(VI) species and functional black water organic fraction. The initial work was optimization of Cr(VI) determination using UV-Visible Spectrophotometry with diphenylcarbacide as complexing agent and preparation of black water using mixture of 2% HCl and 5% HF with HCl-HF ratio of 1 : 1 (v/v). The quantity of Cr(VI) species adsorbed on black water was calculated by determining the amount of Cr(VI) species in solution before and after interaction. The functional groups in interaction between Cr(VI) species and black water organic fraction was studied qualitatively using infrared spectroscopy. The results showed that optimum condition for Cr(VI) species analysis using UV-Visible spectrophotometry with diphenylcarbacide as complexing agent was at wave length of 540 nm, pH 1,5, 15 - 60 minutes at which complex remain stable, and minimum mol ratio of diphenylcarbacide : Cr(VI) 45 : 1, and has a sensitivity of 1.134 mg/L and detection limit of 0.00495 mg/L. The analysis was not affected by the presence of Cr(III) in concentration less than 40 times of Cr(VI) concentration. After treatment with HCl-HF the quantity of black water organic fraction showing humic acid properties decreased 0,1998 percent. Organic fraction of black water used adsorpted Cr(VI)with capacity of 4,050 mg/g. Keywords: Adsorption, Cr(VI), Black Water
CHARACTERIZATION AND ACTIVATION OF NATURAL ZEOLIT FROM PONOROGO
Authors: Heraldy Eddy , SW Hisyam , Sulistiyono Sulistiyono 
Published: January 2019

Characterization and activation of Natural Zeolite from Ponorogo (ZAP) have been done to improve the quality of zeolite as porous material. Analysis of mineral composition is done using X-Ray Difraction (XRD), Fourier Transform-Infra Red (FTIR) Spectroscopy and metal analysis using Atomic Absorption Spectroscopy (AAS). Characterization of the activated zeolite covered about number of acidic sites, surface area, ratio Si/Al and metal composition (Na, Ca, K and Fe). Activated processes is done using various mineral acid, i.e HCl, HNO3, H2SO4 and HPO4 with each concentration at 1 M and 3 3 hours dipping. The result showed that ZAP has composition Ca-klinoptilolit (43.09 %), gismondin (17.57 %), modernit (4.21 %) and quartz (10.37 %). The most efectif of the acid to activate is HCl and is proved to absorp of Zn in waste water. The effect of chemical activation is increasing the ratio of Si/Al, increasing the surface area and reducing some metal composition. Keywords: natural zeolite, chemical activation, porous material
EFFECT OF IMPREGNATION PROCEDURE OF Pt/γ-AL<sub>2</sub>O<sub>3</sub> CATALYSTS UPON CATALYTIC OXIDATION OF CO
Authors: Triyono Triyono 
Published: January 2019

The oxidation of carbon monoxide by oxygen using two catalysts prepared by two different methods has been investigated. In the first method, catalyst prepared by immersing γ-Al2O3 into the hexa-chloroplatinic acid solution at 80oC for 4 h, resulted Pt/γ-Al2O3 catalyst having platinum highly dispersed on the support. While that of immersing γ-Al2O3 in the hexa-chloroplatinic acid solution at room temperature for 12 h, produced Pt/ γ-Al2O3 catalyst where platinum dispersion was much lower. Catalytic activity test showed that platinum well dispersed on the support enhanced the activity for oxidation of carbon monoxide. The platinum impregnated at room temperature resulted in the poor activity. Keywords: platinum catalyst, alumina, supported material, oxidation
OPTIMATION OF THE INCUBATION TIME FOR ENZYMATIC PRODUCTION OF COCONUT OIL USING THE FRUIT’S LATEX OF Carica papaya L
Authors: Chasani M , S Sri Sutji 
Published: January 2019

Optimisations of incubation time of the enzymatic coconut oil extraction using Carica papaya's latex have been done. These researches were performed based on completed randomised design with varying incubation time (12, 24, 36 and 48 hours) and 3 % inoculums. Experimental data covered of yield, refractive index, water content, acid number, iodine number and organoleptic parameters and then analysed using t-test and regression analysis. The result showed that coconut oil produced by enzymatic reaction had good quality especially in iodine number parameter compared with conventional extraction. From the statistical analysis, the product by 24 hours incubation had the highest yield and best quality. Keywords: Coconut oil, optimization process, enzymatic reaction
INTERACTION BETWEEN Li<sup>+</sup> CATION WITH CROWN ETHERS OF Bz15C5, DBz16C5 AND DBz18C6: MOLECULAR MODELING BASE ON MNDO/d SEMIEMPIRICAL METHOD
Authors: Pranowo Harno Dwi , Anwar Chairil 
Published: January 2019

The aim of this research is to find information about the substituent effect to the structure of crown ether benzo-15-crown-5 (Bz15C5), dibenzo-16-crown-5 (DBz16C5) and dibenzo-18-crown-6 (DBz18C6), and also crown ether selectivity to coordinate a Li+ metal cation. The presence of substituent could change the conformations flexibility of crown ether during interact with metal cation. In this research semi empirical MNDO/d method was used for calculations. Firstly, geometry optimization was conducted to crown ethers structure using MNDO/d methods. The next steps were running the geometry optimization of complexes between cation Li+ with crown ethers. Data were produced from these calculation are the parameter of crown ether structures, structures of the complexes, and the binding energy of the cation-crown ethers. The presence of electron-withdrawing substituents decreased the binding energy while that of electron-donating one increase the binding energy (value of ΔE more negative). The substituents which are increase the degree of symmetry of the cation-crown ether complexes could give the increase of crown ether selectivity to bind the cation. Selectivity of crown ether to bind the cation depends on the structural match between ionic radii of crown ether cavity (the ion-cavity size concept). Bz15C5 what has higher selectivity to bind Li+ than DBz16C5 and DBz18C6. Keywords: selectivity, crown ether, MNDO/d.
COLLABORATIVE TRIAL AND QUALITY CONTROL IN CHEMICAL ANALYSIS
Authors: Narsito Narsito 
Published: January 2019

Abstract This paper deals with some practical problems related to the quality of analytical chemical data usually met in practice. Special attention is given to the topic of quality control in analytical chemistry, since analytical data is one of the primary information from which some important scientifically based decision are to be made. The present paper starts with brief description on some fundamental aspects associated with quality of analytical data, such as sources of variation of analytical data, criteria for quality of analytical method, quality assurance in chemical analysis. The assessment of quality parameter for analytical method like the use of standard materials as well as standard methods is given. Concerning with the quality control of analytical data, the use of several techniques, such as control samples and control charts, in monitoring analytical data in quality control program are described qualitatively. In the final part of this paper, some important remarks for the preparation of collaborative trials, including the evaluation of accuracy and reproducibility of analytical method are also given Keywords: collaborative trials, quality control, analytical data Abstract This paper deals with some practical problems related to the quality of analytical chemical data usually met in practice. Special attention is given to the topic of quality control in analytical chemistry, since analytical data is one of the primary information from which some important scientifically based decision are to be made. The present paper starts with brief description on some fundamental aspects associated with quality of analytical data, such as sources of variation of analytical data, criteria for quality of analytical method, quality assurance in chemical analysis. The assessment of quality parameter for analytical method like the use of standard materials as well as standard methods is given. Concerning with the quality control of analytical data, the use of several techniques, such as control samples and control charts, in monitoring analytical data in quality control program are described qualitatively. In the final part of this paper, some important remarks for the preparation of collaborative trials, including the evaluation of accuracy and reproducibility of analytical method are also given Keywords: collaborative trials, quality control, analytical data
STUDY OF MATRIX EFFECT ON THE ANALYSIS OF Ni AND Pd BY AAS IN THE DESTRUATS OF HIDROCRACKING CATALYSTS USING AQUA REGIA AND H<sub>2</sub>SO<sub>4</sub>
Authors: Trisunaryanti Wega , Mudasir Mudasir , Saroh Siti 
Published: January 2019

The matrix effect of various metals on the analysis of nickel and palladium in destruate of catalysts of Butonian asphalt-derived asphaltene by atomic absorption spectroscopy have been investigated. Samples were dissolved by wet decomposition method using aqua regia and then followed by concentrated H2SO4. The solution was evaporated to dryness on a sand-bath. Study of matrix effect was carried out by comparing the absorbance of Ni and Pd with and without the adding of various concentration of metals in the samples. The calibration curve and standard addition methods were applied in the analysis of Ni and Pd. Result of the study showed that matrix effect toward absorbance of Ni is mostly caused by Al and Si contents in the concentration range of 200-500 ppm. Al content in the concentration of 500 ppm, and Si content in the concentration range of 100-500 ppm cause the matrix effect in the analysis of Pd. However, the change in absorbance of Ni and Pd is still below tolerable limit of 10%. The content of Ni in Pd-Ni / zeolit-Y, Ni-Pd/ zeolit-Y, Mo-Ni/ g-alumina, and Ni-Mo / g-alumina with calibration curve technique were 7.44 ± 0.021; 7.62 ± 0.052; 7.75 ± 0.054; and 2.69 ± 0.062 respectively and with standard addition technique were 6.82 ± 0.066; 7.23 ± 0.112; 7.39 ± 0.099; and 2.35 ± 0.055 respectively. Pd content in Pd-Ni / zeolit-Y and Ni-Pd/ zeolit-Y with calibration curve technique were 2.74 ± 0.044 and 2.49 ± 0.051 and with standard addition technique were 2.90 ± 0.015 and 2.69 ± 0.042. Keywords: matrix effect, analysis of nickel and palladium, aqua regia, H2SO4
Ion Ni<sup>2+</sup> di Dalam Air; Pembentukan Fungsi Potensial Intermolekul
Authors: Setiaji Bambang , Arindah Tutik 
Published: January 2019

Pair potential function of Ni2+-H2O system has been constructed by ab initio method at UHF (Unrestricted Hartre-Fock) level. The basis sets used for energy interaction calculation were LANL2 Double-z ECP of Hay and Wadt for Ni2+ and Double-z Polarization of Dunning for H2O. Construction of pair potential function was done by collecting more than 3000 energy points that represent all interactions of Ni2+ ion and water. The pair potential function of Ni2+-H2O resulted of fitting proses by standard deviation of 3,25 kcal/mol is where AiM, BiM, CiM and DiM are fitting parameter of Ni2+-O or Ni2+-H, riM is distance of i atoms between H2O and Ni2+, q is charge of i atoms of H2O resulted by Mulliken population analysis, and qM is net charge of Ni2+ ion. Keywords: Ni2+ ion in water, intermoleculer potential function.
STUDY OF THE EFFECT OF ETHANOL ADDITION AND SOLUTION HEATING ON THE DETERMINATION OF AMMONIA IN WATER BY INDOPHENOL BLUE METHOD
Authors: Hasri Hasri , Mudasir Mudasir 
Published: January 2019

The effect of ethanol addition and solution heating on the analytical performance of the determination of ammonia in water by indophenol blue method was studied. The addition of ethanol and solution heating was intended to overcome the problem of reproducibility and sensitivity ussually found in the determination of ammonia by indophenol blue method which is carried out in 100 % aqueous media. The determination of ammonia was done indirectly by reacting ammonia in the sample with hypochloride and phenol using nitroprussida as catalyst to yield blue color-intense chromophore of indophenol. The chromophore was then detected by UV-Visible spectrophotometer. The proposed method was applied for the determination of ammonia in various samples of river water located in Yogyakarta and Makassar. Results of the study showed that ethanol addition into analytical solution and solution heating enhanced the formation of indophenol blue. The optimal heating was achieved after 90 minutes of mixing. In ethanol/water medium (50/50, v/v), indophenol blue exhibited maximum absorbance at 648 nm. The analytical performance of ammonia determination by indophenol blue method in this medium is as followed: detection limit = 0.03 ppm, relative standard deviation (RSD) = 2.50 % and the calibration curve was linear in the concentration range of 0.0 - 0.4 ppm with correlation coefficient (r) = 0.9968. Results of ammonia determination in various samples of river water showed that the highest concentration of ammonia (2.421 ppm) was found in Tallo river, Makassar, while the lowest (0.359 ppm) was shown by the river near SGM factory, Yogyakarta. Keywords: Ammonia, Ethanol, Spectrophotometry, Indophenol blue.