28 research outputs found
Organic Fertilizer Production From Cattle Waste Vermicomposting Assisted by Lumbricus Rubellus
Composting is decomposition of compound in organic waste by specific treatment using microorganism aerobically. Natural composting for producing organic fertilizer from manure and market waste utilize long time processing and less equal to the market demand. Vermicomposting is a technique to produce high quality compos fertilizer from biodegradable garbage and mixture of red worm (Lumbricus Rubellus). In conventional compos production took 8 weeks of processing time, in vermicomposting only took half processing time of conventional technique. It is occurred by red worm additional ease cellulose degradation contain in manure which is could not decomposed with composting bacteria. The purposes of this research are to investigate the effect of manure comparison to red worm growth and to evaluate the effect of comparison between manure and market waste to red worm growth. This research was conducted by vary the weight of red worm (100 gr, 200 gr, 300 gr, 400 gr, 500 gr) and market waste addition (50 gr, 100 gr, 150 gr, 200 gr, 300 gr). Moreover, 3 kg of manure was mixed by various weight of red worm, while variation of market waste addition was involved 500 gr red worm and 3 kg manure mixture. Optimum increasing weight of red worm that was obtained by 100 gr red worm addition is 160 gr within 2 weeks. In added market waste variation, the highest increasing of red worm was resulted by 50 gr market waste addition, with 60 gr increasing weight of red worm. Production of casting fertilizer was highly effected by composition of used materials such as medium, manure and red worm comparison as well as market waste additiona
Molecular simulations of droplet evaporation processes: Adiabatic pressure jump evaporation
For the assessment of droplet evaporation by molecular dynamics simulations prescriptions for the calculation of the time dependent
number of droplet particles and of several space and time dependent hydrodynamic quantities like density, drift velocity and temperature
are given. Then two cases of adiabatic pressure jump evaporation are treated by molecular simulations using a Lennard-Jones potential.
First, a droplet wrapped by its vapour, and second, a bare droplet is brought into vacuum. In both cases evaporation takes place and
after a transition process a new droplet-vapour equilibrium is reached at lower temperature. Results are presented for the space and time
dependent hydrodynamic quantities as well as for the number of droplet particles as function of time
Modelling and Simulation of Momentum, Heat, and Mass Transfer in a Deep-Bed Grain Dryer
This article concerns the modelling and simulation of a deep-bed grain dryer in a large diameter-column. Two-dimensional (2D) models of deep-bed grain dryers were built by considering simultaneously momentum, heat, and mass transfer in the drying phase together with coupled heat and mass balance in the grain phase. The dynamic equations are solved numerically by using finite difference method. The momentum equations are applied to simulate pressure drop and velocity field of the drying air across the bed. The mass and heat balance in the two phases determine the profile of temperature and moisture content in both phases. Further, drying rate curves for various temperature of inlet drying gas together with moisture content of grain were simulated. The simulated profiles are in close agreement with experimental data
NON-LINEAR PARAMETER ESTIMATION OF EMC/ERH CORRELATIONS FOR GRAIN-TYPE PRODUCTS
A mathematical prediction of corn sorption isotherm was developed for three-parameter EMC correlation such as Modified-Henderson, Modified-Chung-Pfost, Modified-Oswin, and Modified-Halsey. Moisture sorption experimental data were determined using a dynamic method at temperature 30 oC, 40 oC and water activity range from 0.07 to 0.75. The vapor pressure regulation of air surrounding the grains was adjusted by varying sulfuric acid solution. Non-linear regression algorithms such as Simplex and/or Rosenbrock algorithm were used to fit the measured data to the EMC relations. The generalized correlation coefficient (R2) and the mean relative deviation were in the range of 0.90-0.99 and 2 % - 8 % respectively, in which comparison between predicted and experimental sorption isotherms. From the parameters of correlation, it is possible to get the best equations among them to represent equilibrium moisture content of corn grains. The Modified-Henderson and Modified-Oswin equations give the best model for predicting the adsorption and desorption EMC of corn grain for given range of temperature and water activity
Penentuan Konstanta Pengeringan Dalam Sistem Pengeringan Lapis Tipis (Thin Layer Drying)
Drying process was mainly influenced by the drying air condition, internal properties of solid and the drying system. The drying kinetic was controlled by a drying constant (K) with respect to thin layer drying model dependent on drying air flow-rate, moisture diffusivity, drying air conditions, the structure of solid micro porous, and solid moisture content and thickness. Coefficients of the drying constant were determined by fitting an empirical model on a set of experimental data of the thin layer drying. The empirical drying constants for potato was expressed as function of solid moisture content (X) and drying air temperature (T) investigated in the temperature and the moisture content ranges of 40 β 60 oC, and 0,001 β 0,45 kg water/kg dry solid, respectively as described as follows: K=0.00458 exp(-0.2474X) exp(-7401.9/RT). The Levenberg-Marquardt algorithm was implemented for the model fitting to determine the model coefficients. The drying kinetic including the drying constant can be used to predict the drying dynamic precisely in the thin layer drying system
PEMILIHAN KORELASI KANDUNGAN AIR SETIMBANG (TIGA PARAMETER) UNTUK PRODUK PERTANIAN PADI
This paper concerns about selection of equilibrium moisture content-correlation of paddy, based on non-linear parameter estimation. The mathematical prediction of paddy sorption isotherm was developed for three-parameter EMC correlations such as that of Modified-Henderson, Modified-Chung-Pfost, Modified-Oswin, and Modified-Halsey. Moisture sorption experimental data were determined using a dynamic method at temperature 30 oC, 40 oC and water activity range of 0.07 - 0.75. The vapor pressure variations of air surrounding the grains were adjusted by varying sulfuric acid solution. Non-linear regression algorithms such as Simplex and/or Rosenbrock were used to fit the measured data to the EMC correlations. The study found that generalized correlation coefficient (R2) and the mean relative deviation were in the range of 0.85-0.99 and 1 % - 11 % respectively. In view of selection, it will be able to get the best equations among them to represent equilibrium moisture content of paddy grains. Furthermore, the Modified-Henderson correlation gives the best model for predicting the adsorption and desorption EMC for the range of temperature and water activity studied
STUDI EKSPERIMENTAL ALAT PENGERINGAN GABAH SISTEM RESIRKULASI KONTINYU TIPE KONVEYOR PNEUMATIK
Drying paddy by using conventional method is irrelevant to used nowadays. The need of grain increasing each year is one of the main factor that pushes scientist to invent new methods of drying paddy grain. The old method is unusefull since it takes up space, needed the sun as the drying media which causes a long drying time. One of the alternative of drying paddy grain is by using mechanic dryer. By using this type of dryer, the process of drying takes faster comparing to the old method and the distribution of grain is supplied continuously. The dryer which uses pneumatic conveyor can be one of the solution due to its less energy consumption, a better drying result and high drying capacity. The variable used to identify drying performance is temperature and loading weight. From the experiment, it is resulted that the best temperature for drying paddy grain is 60 C with the weight loading of 150 gram
Optimalisasi Kompetensi Profesional Guru Bahasa Inggris Perhotelan SMK melalui Pemahaman Pengembangan Materi Ajar Berbasis Critical Pedagogy
Kegiatan ini bertujuan untuk memberikan pemahaman terkait pengembangan materi ajar berbasis critical pedagogy dalam memaksimalkan kompetensi profesional guru Bahasa inggris Sekolah Menengah Keguruan (SMK). Ini perlu dilakukan dikarenakan beberapa masalah yang dihadapi dalam praktik pembelajaran, diantaranya: materi Bahasa inggris yang kurang relevan terkait dengan kebutuhan siswa program perhotelan; dan perbedaan persepsi guru terkait materi apa yang akan diajarkan di jurusan perhotelan Sekolah Menengah Kejuruan (SMK). Untuk mengatasi permasalahan tersebut, beberapa kegiatan telah dilakukan seperti sharing knowledge, pendampingan penyusunan dan implementasi materi dan diskusi kolaboratif sebagai langkah evaluasi dan refleksi. Pemilihan pendekatan critcal pedagogy sebagai dasar pengembangan materi ajar diyakini mampu mengaitkan teori dan praktik sebagai upaya pemberdayaan masyarakat di lingkungan sosial. Dari materi berbasis critical pedagogy tersebut kemudian siswa terdorong untuk beradaptasi dengan cepat dan berpikir kritis
Sains fisika 1 : untuk SMP kelas 1, berdasarkan kurikulum berbasis kompetensi
Jilid 1xvi, 226 p. : il.; 24 cm