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Contact Name
Purwatiningsih, Ph.D
Contact Email
jid@unej.ac.id
Phone
331334293
Journal Mail Official
jid@unej.ac.id
Editorial Address
Fakultas MIPA Universitas Jember Jl. Kalimantan 37 Kampus Tegalboto Jember 68121
Location
Kab. jember,
Jawa timur
INDONESIA
Jurnal ILMU DASAR
Published by Universitas Jember
ISSN : 14115735     EISSN : 24425613     DOI : -
Jurnal ILMU DASAR (JID) adalah jurnal ilmiah yang melingkupi bidang matematika, fisika, kimia dan biologi. Naskah yang diusulkan untuk diterbitkan Jurnal Ilmu Dasar adalah naskah yang belum pernah diterbitkan dan atau tidak sedang dipertimbangkan penerbitannya di majalah lain. Jurnal Ilmu Dasar menerima tulisan hasil penelitian dasar (bukan aplikasi) untuk bidang matematika, kimia, fisika, dan biologi. Naskah ilmiah ditulis dalam bahasa Indonesia atau dalam bahasa Inggris yang baik. Secara lebih detail dapat dilihat dari pedoman penulisan.
Articles 434 Documents
X-Ray Diffraction and Microstructure of Tin Dioxide with Addition of Fe Manurung, Posman
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Preparation and characterization of tin dioxide, SnO2, had been carried out by precipitation process of SnCl2.2H2O in ammonia and aqua solutions with comparison of 1 : 7. FeCl3 was added to solution with variation of 0, 0,1, 0.2, 0.5 and 1.0 gram respectively and then sintered at 900°C. The X-ray diffraction (XRD) analysis shows that the intensity of diffraction increases with the addition of Fe. The addition of Fe does not cause the new phase. Generally, the Bragg angle is relative same for all samples that means Fe does not change significantly the cell parameters. Scanning electron microscopy (SEM) image shows the microstructure changed with the addition of Fe. On the small addition, the microstructure tends to oval and on the larger addition to plateau. Keywords: Tin dioxide, diffraction, microstructure
Estimation and Statistical Test in Bivariate Binary Probit Model Ratnasari, Vita; Purhadi, Purhadi; Ismaini, Ismaini; Suhartono, Suhartono
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

One of the models that can be used to analyze two binary response variables data is bivariate binary probit model. This paper tried to estimate the parameters of bivariate binary probit model using Maximum Likelihood Estimationmethod,whereastoget thestatisticaltestusingMaximumLikelihoodRatioTestmethod. Keywords : Bivariate binary probit model, maximum likelihood estimation, maximum likelihood ratio test
Study of the Activity of Ni/H5-NZA Catalyst and Co(II)/H5NZA to Catalytic Cracking Methyl Ester Jatropha Andarini, Novita
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

The catalytic activity of H5NZA, Ni/H5NZA and Co/H5NZA converting methyl ester jatropha have been studied. The reaction was proceeded in flow fixed bed reactor that operated at the temperature of 450oC for 60 minutes using butanol as the catching-feed. The catalysts were prepared by acidifying of natural zeolite using HF 1%, HCl 6 M and NH4Cl 0.1 M), it was then hydrothermally treated and calcinated with nitrogen. Finally, it is oxidized and impregnated by ion nickel and cobalt (2% w/w). Meanwhile, the methyl ester jatropha as feed stocks was prepared by reacting a jatropha oil with sodium methoxy. The catalytic process was done by placing a catalyst on the flow fixed bed reactor at the temperature of 450oC and flowing a methyl ester and butanol to the reactor for 60 minutes with a fixed flow rate. A liquid fraction have been produced and were then characterized using GC. The maximum percentage conversion of methyl ester was found to be 94.6891% using catalyst of zeolite acid H5NZA which were indicated by a reduction signal of the original methyl ester. The selectivity of this catalyst was performed by the specific product on the retention time of <2.5 minutes. The modified catalysts which were impregnated by the ion Ni and Co shown their selectivity on range of retention time of 2.5-5.0 and 5.0-10 minutes respectively. Keywords : Methyl ester jatropha, catalyst, zeolite, impregnation, Nickel and Cobalt
Outlier Detection in Observation at Multivariate Linear Models with Likelihood Displacement Statistic-Lagrange Method Makkulau, Makkulau; Linuwih, Susanti; Purhadi, Purhadi; Mashuri, Muhammad
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

here are two different outliers, i.e outlier in observations and outlier in models. The existing outlier detection method in models is using common Likelihood method. The limitation of this method is the optimal value produced might be not the real optimal values. This research yields a method for outlier detection in multivariate linear models with Likelihood Displacement Statistic-Lagrange method (LDL method). This method uses multiplier Lagrange with constraint the confidence interval of parameter’s vector. This parameter’s vector is obtained from the data set which is outlier free. This parameter estimation process uses numerical method with Karush-Kuhn Tucker condition in nonlinear programming. This method compares between LDL value and the table F value that follows the distribution of F value to indentify the outlier in models. Keywords : Distribution of F, Likelihood Displacement Statistic-Lagrange, multivariate linear models, nonlinear programming, outlier detection
Development System and Reconstruction Method of Translation-Rotation Computed Tomography Using Efficient Sampling Ukhrowiyah, Nuril; Ain, Khusnul
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Translation-rotation computed tomography system has been successfully built on this research. The system can be used for the scanning process with sampling method square and hexagonal. It also has been obtained interpolation and reconstruction methods are able to produce reconstruction images fast and accurate. Translation-rotation computed tomography system was built by assembling several instruments that have been made and have existed in the laboratory. Performance of the system was tested by scanning test object. Scanning process has been conducted with the circular test object from metal. Scanning process carried out by performing various of three resolutions, i.e. 31 pixels × 31 pixels, 63 pixels × 63 pixels and 127 pixels × 127 pixels. The sinogram data are square and hexagonal patterns. The sinograms are reconstructed by SCFBP (Summation Convolution Filtered Back Projection) and ART (Algebraic Reconstruction Technique) reconstruction method. Hexagonal sinogram pattern has been interpolated by vertical, horizontal and cross interpolation before reconstructed by ART and SCFBP reconstruction method. Reconstruction image of hexagonal pattern were analyzed by comparing the line profile and its rmsd value of the reconstruction image of square pattern. Performance of the constructed system in the research produced reconstruction image appropriated with objects test. The best interpolation for hexagonal sinogram pattern is cross interpolation. The ART methods produced image reconstruction better than SCFBP reconstruction methods. Keyword : Computer tomography, efficient sampling
Pore Structure and Morphology Characterizations of Mesoporous ZSM-5 Synthesized at Various Aging Time Hartanto, Djoko; Purbaningtias, Tri Esti; Fansuri, Hamzah; Prasetyoko, Didik
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Mesoporous ZSM-5 has been successfully synthesized at various aging time of 6, 12 and 24 h. Mesoporous ZSM-5 was synthesized using cetyltrimethylammonium bromide (CTABr) as a template. Synthesis was carried out hydrothermally with aging and crystallization temperature at 60oC and 150oC. XRD patterns of the resulted material showed diffraction lines at 2θ = 23o and at small angle (2θ < 5o) which is characteristic of the structure of ZSM-5 and the existing of the mesoporous material. It was found that crystallinity of the sample increased at longer aging time. The result of nitrogen gas sorption analysis showed that all samples have pore size about 3,8 nm. The porosity of ZSM-5 decreased with shorter of aging time. ZSM-5 synthesized at 6 h aging time has the highest porosity of 72.57%. Aging time also affected the particle size, the longer the aging time, the smaller the particle size. The particle size was ranging 1.25 – 1.0 μm. Keywords: Pore structure, morphology, mesoporous ZSM-5, aging time
Regression for Exploring Rainfall Pattern in Indramayu Regency Djuraidah, Anik; Wigena, Aji Hamim
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

uantile regression is an important tool for conditional quantiles estimation of a response Y for a given vector of covariates X. It can be used to measure the effect of covariates not only in the center of a distribution, but also in the upper and lower tails. Regression coefficients for each quantile can be estimated through an objective function which is weighted average absolute errors. Each quantile regression characterizes a particular aspect of a conditional distribution. Thus we can combine different quantile regressions to describe more completely the underlying conditional distribution. The analysis model of quantile regression would be specifically useful when the conditional distribution is not a normal shape, such as an asymmetric distribution or truncated distribution. In general, rainfall in Indramayu regency during 1972-2001 at 23 stations is highly variable in amount across time (month)andspace. So,thefirstobjectiveoftheresearchisreducingthevariabilityinspaceusingclassification of the rainfall stations. The second objective is modelling the variability in time using quantile regression for every cluster of rainfall stations. The result shows that there are two clusters of rainfall stations. The first cluster has higher amount of rainfall than the second cluster. The coefficient of quantile regression for quantile 50 and 75 percent are similar, but for quantile 5 and 90 percent are very different. Exploring pattern of rainfall using quantile regression can detect normal or extreme rainfall that very useful in agricultural. Keywords : Quantile, quantile regression, cluster, rainfall
The Effects of Oxygen Content, Deposition Rate and Annealing Towards Thin Film of Indium Tin Oxide Muslimin, Muslimin
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Indiun tin oxide is one of the materials that has physical properties, rarely seen in other materials. Indium tin oxide properties have the main role in developing the technology of thin film shown through its properties. Therefore, many people study on it since its widespread application to the technological industries. Coating process was carried out by mixing 90 % of In2O3 and 10 % SnO2 on the glass substrate by means of sputtering. During the process of oxygen was added 2.50%, 3.70%, 5,10%, 6.15% and 8.90%. The deposition rate was respectively 4.21 nm/s and 2.25 nm/s. The Indium tin oxide for each condition was annealed at 175oC and 250oC in a vacuum of 10-3 mBarr for 60 minutes. and the micro structure using the x-ray diffraction. Oxygen conten, deposition rate and annealing resulted in the changes of microstructure of indium tin oxide. These changes are mostly resulted from the changes in microstructure such as grain size and lattice constant. Keywords : Deposition rate, oxygen content, annealing, microstructure
Recycle Waste Glass for Thermal Insulator Budi, Agus Setyo; Sujito, Sujito
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Series of ceramics from recycle waste glass and mica powder have successfully been made and their physical properties of these glasses which include density, bulk modulus, volume expansion and compressive strength have been determined. Comparison of their physical specification to the conventional insulators has also been made. The results show that these ceramics exhibit reasonable mechanical, thermal and physical properties to be a potential thermal insulators. Keywords : Ceramics, mica, thermal conductivity id
Production Optimization and Cellulose System Characterization of Bacillus circulans Local Strain Using Inducer Avicel Susanti, Evi
Jurnal ILMU DASAR Vol 12, No 1 (2011)
Publisher : Fakultas MIPA Universitas Jember

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Abstract

Exploration of aerobic bacteria which can produce cellulase system is very important to discover potential celulase resourse which can hydrolysis lignocelulose waste into glucose. The aimed of this researched were determine optimum condition of cellulase system production in Berg’s media with avicel as inducer and it’s characterization. Bacillus circulans local strain from laboratory of Microbiology ITB produced consist of CMC- ase(111.11U/mL)andavicelase(55.56U/mL)inBerg’smediumcontain0.5%avicel, pH=9.0and5daysof incubation. Characteristic of this cellulase system were: (1) optimum level of CMC-ase (129.97 U/mL) and avicelase (87.96 U/mL) was obtained at pH= 7.0, temperature 50oC and 2 hours incubation, (2) Vmaks and Km of CMC-ase was 1000 μg glucose/hour and 5%, Vmaks and Km of avicelase was 200 μg glucose/hour and 1.2%, (3) capable of hidrolizing sugarcane, corn cob and rice bran during optimum condition and released glucose 262 ppm, 81 ppm and 78 ppm. This research encouraged that Bacillus circulans capable of producing cellulose system with high activity and suggested to degradated lignocelluloses as feedstocks of bioetanol. Keyword: Cellulase system, Bacillus circulans, avicel

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