Kajian Sistem Pengukur Daya Reaktor Pada Kanal Daya Tinggi

AbstrakTelah dilakukan kajian tentang  sistem pengukur daya reaktor pada kanal daya tinggi serta telah dicoba perancangan alat ukur daya reaktor untuk tiga dekade teratas atau dalam rentang 1% s.d. 100% pengukuran daya. Sistem pengukur daya reaktor pada kanal daya tinggi dibentuk sebagai pengukur arus luaran detektor nuklir yang ditempatkan dalam tangki reaktor, proporsional terhadap besarnya fluks neutron yang terdeteksi dan seterusnya adalah proporsional dengan daya thermal reaktor. Sistem dibentuk sebagai pengukur arus yang berkisar dari 1 mikroampere s.d. 1 miliampere dalam tiga skala ukur yang dikontrol secara otomatis dengan memanfaatkan sistem mikrokontroler. Dari hasil pengujian di laboratorium dengan menggunakan sumber arus yang presisi dapat disimpulkan bahwa sistem pengukur daya reaktor yang dirancang dapat digunakan dan dapat dikembangkan lebih lanjut menjadi pengukur daya reaktor untuk kanal daya menengah.Kata kunci:pengukur daya reaktor, pengukur arus, mikrokontroler.AbstractA reactor power measuring system has been examined at high-power channel. Reactor power measuring device also has been designed for top three decades or within the range of 1% - 100% power measurement. Reactor power measuring system at high-power channel is formed as a nuclear detector output current meter which is placed inside the reactor tank. This current measurement is propotional to detected neutron flux and so is propotional to the thermal power reactor. This system was established for measuring currents range from 1 microampere "“ 1 miliampere in three scale measurement which is controlled automatically using microcontroller system. From the laboratory tests using a precision current source, it can be conclude that designed reactor power measuring system is able to be used. It also can be developed further for  measuring reactor power at medium power channel.Keywords:reactor power meter, current meter, microcontroller

THE EFFECT OF HEATING ON PHYSICOCHEMICAL CHARACTERISTICS OF RICE BRAND OIL

Rice bran oil has a potential in lowering blood cholesterol. The oil content extracted from rice bran isa influenced by several factors such as raw material and processing method. This research was conducted to study the effect of heating on the physicochemical characteristics of rice bran oil. The study was carried out at the Food Technology and Nutrition Laboratory and Biotechnological Science Laboratory of the Inter University Center, Bogor Agricultural University, from February to MAy 1997. Bran used was from IR64 rice variety obtained from a local milling rice in Tambak Dahan, Binong-Subang, West Java. Rice bran was subjected to different period of heating (0, 15 and 30 minutes) at 121oC by using an autoclave, then the oil was extraxted by using hexane solvent followed by standard processing at room temperature (28-30oC) and 40oC for two hours. The parameters observed were oil content and its quality such as saponification, iodine, acid, peroxide, tiobarbituric acid, and triglyceric acid values as well as oil color. The results showed that oil extracted from rice bran was high, ranging from 9.65 to 11.02%. Heating (sterilizing) of the rice bran for 15 and 30 minutes at 120oC proir to extraction increased the oil content. The Quality of rice bran oil extracted met the standard of AOAC

Media Pembelajaran Surat Kabar dalam Meningkatkan Motivasi, Aktivitas terhadap Prestasi Belajar Ekonomi

This research aims to determine the utilization of instructional media newspapers effect in increasing motivation and activities on learning achievement economics. The method is ex post facto. Hypothesis was analized using path analysis.The results showed that there was a significant effect of: (1) utilization instructional media newspapers on motivation; (2) utilization instructional media newspapers on activity; (3) motivation on learning achievement; (4) activities on learning achievement; (5) utilization instructional media newspapers on learning achievement; (6) utilization instructional media newspapers and motivation on learning achievement; (7) utilization instructional media newspapers and activities on learning achievement.Penelitian ini bertujuan untuk mengetahui apakah ada pengaruh pemanfaatan media pembelajaran surat kabar dalam meningkatkan motivasi dan aktivitas belajar terhadap prestasi belajar. Metode yang digunakan adalah ex post facto. Pengujian hipotesis menggunakan analisis jalur. Hasil penelitian menunjukkan bahwa ada pengaruh yang signifikan: (1) pemanfaatan media pembelajaran surat kabar terhadap motivasi; (2) pemanfaatan media pembelajaran surat kabar terhadap aktivitas; (3) motivasi terhadap prestasi belajar Ekonomi; (4) aktivitas terhadap prestasi belajar Ekonomi; (5) pemanfaatan media pembelajaran surat kabar terhadap prestasi belajar Ekonomi; (6) pemanfaatan media pembelajaran surat kabar dan motivasi terhadap prestasi belajar; (7) pemanfaatan media pembelajaran surat kabar dan aktivitas terhadap prestasi belaja

The Effect of Heating on Physicochemical Characteristics of Rice Brand Oil

Rice bran oil has a potential in lowering blood cholesterol. The oil content extracted from rice bran isa influenced by several factors such as raw material and processing method. This research was conducted to study the effect of heating on the physicochemical characteristics of rice bran oil. The study was carried out at the Food Technology and Nutrition Laboratory and Biotechnological Science Laboratory of the Inter University Center, Bogor Agricultural University, from February to MAy 1997. Bran used was from IR64 rice variety obtained from a local milling rice in Tambak Dahan, Binong-Subang, West Java. Rice bran was subjected to different period of heating (0, 15 and 30 minutes) at 121oC by using an autoclave, then the oil was extraxted by using hexane solvent followed by standard processing at room temperature (28-30oC) and 40oC for two hours. The parameters observed were oil content and its quality such as saponification, iodine, acid, peroxide, tiobarbituric acid, and triglyceric acid values as well as oil color. The results showed that oil extracted from rice bran was high, ranging from 9.65 to 11.02%. Heating (sterilizing) of the rice bran for 15 and 30 minutes at 120oC proir to extraction increased the oil content. The Quality of rice bran oil extracted met the standard of AOAC

Massa Protein dan Kalsium Daging Ayam Broiler Akibat Penambahan Sinbiotik dalam Ransum

Penelitian ini bertujuan mengkaji sinbiotik kombinasi inulin ekstrak umbi gembili (IEUG) dengan Lactobacillus plantarum dalam pakan ayam broiler terhadap massa kalsium dan protein daging. Materi yang digunakan adalah DOC ayam broiler sejumlah 144 ekor unsexed, dengan bobot badan awal 45,68 ±1,52 gram. Ransum yang digunakan selama pemeliharaan mengandung PK 22% dan energi metabolis (EM) 3000 kkal/kg. Pemberian perlakuan dilakukan umur 0 – 42 hari. Penelitian menggunakan rancangan acak lengkap 4 perlakuan dengan 6 ulangan, dan setiap unit percobaan terdapat 6 ekor ayam. Penambahan sinbiotik yang diterapkan yaitu T0 = 0 ml/100 g ransum,  T1 = 1 ml/100  g  ransum,  T2 = 2  ml/100 g  ransum dan  T3 =  3 ml/100  g  ransum.  Parameter yang diambil kadar protein, kadar kalsium, massa protein dan massa kalsium daging. Data hasil penelitian dianalisis menggunakan analisis ragam uji F, apabila terdapat pengaruh perlakuan yang nyata, dilanjutkan uji Duncan. Hasil penelitian memperlihatkan semakin tinggi dosis penambahan sinbiotik berpengaruh nyata (P<0,05) meningkatkan kadar protein dan kalsium daging, massa protein dan massa kalsium daging. Kesimpulan penelitian ini adalah sinbiotik 2 ml/100 g ransum meningkatkan massa protein dan kalsium daging, sinbiotik 1 ml/100 g ransum meningkatkan kadar kalsium daging sedangkan sinbiotik 2 dan 3 ml/100 g ransum meningkatkan kadar protein

Microwave resonator-based microfluidic sensors fabricated using 3D-printing technology

Microwave resonators can be utilized as precision, fast, selective, and non-invasive sensors for reagent and material characterisation. The quality factor (Q-factor) of a microwave resonator determines its dielectric sensing performance, and the value of Q-factor can be improved by the resonator structure optimisation. However, conventional microwave resonator fabrication can be a complex, time-consuming process that constrains the device prototyping and development. Here we present a low-cost, fused filament 3D printing method to effectively fabricate integrated, split-ring microwave resonators with fluidic inducts, operating in the frequency range 2 to 4 GHz. Finite element modelling is employed to simulate the microwave resonation of sensing aqueous droplets in continuous mineral oil flow, using COMSOL Multiphysics software. We evaluate the sensing performance of different 3D-printed microwave resonators with geometrical variations of ring shapes, sizes, and numbers of split gaps, focusing on the increase of their Q-factors for improved sensitivity. Our work demonstrates a rapid prototyping approach to optimise microwave resonator, that can be applied to flow chemistry and engineering biology applications for functional soft material development purposes

Ion structure factors and electron transport in dense Coulomb plasmas

The dynamical structure factor of a Coulomb crystal of ions is calculated at arbitrary temperature below the melting point taking into account multi-phonon processes in the harmonic approximation. In a strongly coupled Coulomb ion liquid, the static structure factor is split into two parts, a Bragg-diffraction-like one, describing incipient long-range order structures, and an inelastic part corresponding to thermal ion density fluctuations. It is assumed that the diffractionlike scattering does not lead to the electron relaxation in the liquid phase. This assumption, together with the inclusion of multi-phonon processes in the crystalline phase, eliminates large discontinuities of the transport coefficients (jumps of the thermal and electric conductivities, as well as shear viscosity, reported previously) at a melting point.Comment: 4 pages, 2 figures, REVTeX using epsf.sty. Phys. Rev. Lett., in pres

Equation of state of fully ionized electron-ion plasmas

Thermodynamic quantities of Coulomb plasmas consisting of point-like ions immersed in a compressible, polarizable electron background are calculated for ion charges Z=1 to 26 and for a wide domain of plasma parameters ranging from the Debye-Hueckel limit to the crystallization point and from the region of nondegenerate to fully degenerate nonrelativistic or relativistic electrons. The calculations are based on the linear-response theory for the electron-ion interaction, including the local-field corrections in the electronic dielectric function. The thermodynamic quantities are calculated in the framework of the N-body hypernetted-chain equations and fitted by analytic expressions. We present also accurate analytic approximations for the free energy of the ideal electron gas at arbitrary degeneracy and relativity and for the excess free energy of the one-component plasma of ions (OCP) derived from Monte Carlo simulations. The extension to multi-ionic mixtures is discussed within the framework of the linear mixing rule. These formulae provide a completely analytic, accurate description of the thermodynamic quantities of fully ionized electron-ion Coulomb plasmas, a useful tool for various applications from liquid state theory to dense stellar matter.Comment: 13 pages, 2 tables, 7 figures, REVTeX using epsf.sty. To be published in Phys. Rev. E, vol. 58 (1998

Macrophages fine-tune pupil shape during development

Tissue macrophages, which are ubiquitously present innate immune cells, play versatile roles in development and organogenesis. During development, macrophages prune transient or unnecessary synapses in neuronal development, and prune blood vessels in vascular development, facilitating appropriate tissue remodeling. In the present study, we identified that macrophages contributed to the development of pupillary morphology. Csf1op/op mutant mice, in which ocular macrophages are nearly absent, exhibited abnormal pupillary edges, with abnormal protrusions of excess iris tissue into the pupillary space. Macrophages located near the pupillary edge engulfed pigmented debris, which likely consisted of unnecessary iris protrusions that emerge during smoothening of the pupillary edge. Indeed, pupillary edge macrophages phenotypically possessed some features of M2 macrophages, consistent with robust tissue engulfment and remodeling activities. Interestingly, protruding irises in Csf1op/op mice were only detected in gaps between regressing blood vessels. Taken together, our findings uncovered a new role for ocular macrophages, demonstrating that this cell population is important for iris pruning during development

Solid molecular hydrogen: The Broken Symmetry Phase

By performing constant-pressure variable-cell ab initio molecular dynamics simulations we find a quadrupolar orthorhombic structure, of $Pca2_1$ symmetry, for the broken symmetry phase (phase II) of solid H2 at T=0 and P =110 - 150 GPa. We present results for the equation of state, lattice parameters and vibronic frequencies, in very good agreement with experimental observations. Anharmonic quantum corrections to the vibrational frequencies are estimated using available data on H2 and D2. We assign the observed modes to specific symmetry representations.Comment: 5 pages (twocolumn), 4 Postscript figures. To appear in Phys. Rev. Let