Infiltration Kinetics Study And Processing Of Layered Graded Al2o3-zro2 Composite

INFILTRATION KINETICS STUDY AND PROCESSING OF LAYERED GRADED Al2O3-ZrO2 COMPOSITE. Layered graded Al2O3-ZrO2 composite was successfully synthesised through infiltration of porous Al2O3 preform with a solution containing ZrOCl2.8H2O. The infiltration rate of liquid into porous Al2O3 preformhad also been investigated. It was found that the infiltration rate equation proposed by Washburn is most suitable for describing the effects of preform sintering temperature, viscosity and multiple infiltrations on the infiltration behaviour, whereas the influence of applied pressure is consistent with the model proposed by Darcy, where the applied pressure enhances the infiltration rate behaviour. Depth profilling of layered graded Al2O3-ZrO2 composite was characterised by x-ray diffraction, the result shows that the concentration of ZrO2 decreased with depth, while that of Al2O3 increased with depth

Komposisi Tanaman Agroforestri dan Kontribusinya terhadap Pendapatan Rumah Tangga di Desa Pesawaran Indah Kabupaten Pesawaran Lampung

Agroforestry is a land use management system by combining agriculture and forestry and or husbandry to achieved yield optimalization (Indriyanto, 2006). Agroforestry systems with mixed garden pattern consist various types of plants that perform a different composition of plants so there are varied incomes from one place to another. This study aims to: (1) identifying the composition of agroforestry based on INP and its effect on income, (2) analyze the composition of the contribution of agroforestry products to total farm household income. Methods of data collection for species composition using purposive sampling while for the respondent farmers using stratified random sampling. Data analysis using quantitative descriptive analysis method. The results showed that the largest contributes of the composition of plant in three zones, namely the upper, middle, and bottom obtained on the composition of IX which is located in the lower zone of Rp 23,127,404, -/ha/yr with highest INP of cocoa is 94.86%. The magnitude of the average farmer\u27s total income from each source of income from agroforestry to Rp 36.992.171/ha/yr and non-agroforestry amounting to Rp 9.312.500/yr. The magnitude of the contribution of agroforestry systems to farmers\u27 incomes Pesawaran Indah Villages of 91.44%, meaning that agroforestry provides a major contribution to the household income of farmers

Synthesis and characterisation of gel-derived mullite precursors from rice husk silica

The sol-gel synthesis and characterization of mullite precursor derived from rice husk silica and aluminum nitrate hydrate [(Al(NO3)3·9H2O] has been investigated. The samples were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) coupled with Rietveld analysis, and scanning electron microscopy (SEM). FTIR results showed the presence of Si-O-Si, Al-O-Al, and Si-O-Al functional groups, which were associated with mullite, corundum, quartz, and cristobalite, as verified by XRD analysis. It is concluded that mullite formation started at 1150 °C, and its abundance increased rapidly with an increase in temperature from 1150 to 1350 °C, resulting in increased phase content from 30.9 to 67.7 wt%. Although mullite was formed at a low temperature, the complete reaction between corundum and silica to form mullite was not achieved. This finding demonstrated that rice husk silica is a potential alternative raw material for the production of mullite ceramic

Applicability of condensation particle counters to measure atmospheric clusters

This study presents an evaluation of a pulse height condensation particle counter (PH-CPC) and an expansion condensation particle counter (E-CPC) in terms of measuring ambient and laboratory-generated molecular and ion clusters. Ambient molecular cluster concentrations were measured with both instruments as they were deployed in conjunction with an ion spectrometer and other aerosol instruments in Hyytiälä, Finland at the SMEAR II station between 1 March and 30 June 2007. The observed cluster concentrations varied and ranged from some thousands to 100 000 cm -3. Both instruments showed similar (within a factor of ~5) concentrations. An average size of the detected clusters was approximately 1.8 nm. As the atmospheric measurement of sub 2-nm particles and molecular clusters is a challenging task, we conclude that most likely we were unable to detect the smallest clusters. Nevertheless, the reported concentrations are the best estimates to date for minimum cluster concentrations in a boreal forest environment

The Identification of Fishing Ground Area with MODIS Satellite Image (Case Study: South Coast of West Java)

According to UNCLOS, Indonesian marine territorial covers an area equal to around 2.8 million square kilometers inner archipelagic seas. Though the Indonesian water region is very wide, the resource within it is not yet been exploited optimally. Indonesia still has problems that have to be copped with, including identification of marine fishing ground areas. This report proposes a technology to make the fish-catching be more efficient and effective with the help of MODIS satellite image in term of Surface Temperature and chlorophyll-a computation. Data conversion from digital number to Water Brightness Temperature are performed. The determination of potential fishing ground area were conducted based on temperature and chlorophyll-a parameters which serve as an indicator of upwelling and observations were carried out on parameters which show this phenomenon. Based on the result, during May 2004 the upwelling process were not happened yet, and it seems to occur in June 2004. It showes by the decreasing of water temperature in South Coast of West Java particularly between the border of West Java and Central of Java. This phenomenon acts as an indicator for the raising of primer productivity and will takes about one month after upwelling to the bloom of phytoplankton

PENGEMBANGAN TEKNOLOGI DESULFURISASI MELALUI METODE CHEMICAL ABSORBER PADA PRODUKSI BIOGAS YANG BERASAL DARI LIMBAH PALM OIL MILL EFFLUENT (POME)

Biogas memainkan peran penting pada pasar energi terbarukan. Berdasarkan Pepres Presiden No. 27 Tahun 2017, Rencana Umum Energi Nasional, target tahun 2025 untuk energi baru terbarukan adalah sebesar 23 %, dimana 489, 8 juta m3 berasal dari Biogas. Biogas dapat dihasilkan dengan proses digester anaerobik limbah cair dari pabrik kelapa sawit atau disebut Palm Oil Mill Effluent (POME). Dalam penelitian ini, dilakukan fermentasi menggunakan continous-stirred-tank-reactor (CSTR) dengan kapasitas 40 L (Patent ID P00201000740) untuk menghasilkan biomethane dan biohydrogen. Setelah proses fermentasi dalam CSTR selama 35 hari, proses fermentasi ini berhasil memproduksi biometana dan biohidrogen sebesar 77,58 % dan 2,75 vol.%, disamping itu juga menghasilkan gas pengotor seperti hidrogen sulfida yang mencapai lebih dari 2000 ppm, yang merupakan gas asam yang akan menyebabkan korosi pada mesin pembakaran dan juga berbahaya bagi kesehatan dan lingkungan. Oleh karena itu, hidrogen sulfida harus dihilangkan (desulfurisasi) dari biogas sebelum pembakaran. Di antara metode penggunaan chemical absorber tampaknya menjadi salah satu metode yang paling menjanjikan untuk menghilangkan H2S. NaOH dengan berbagai konsentrasi (3N, 5 N, dan 10 N) digunakan sebagai absorben untuk menghilangkan H2S. Dari penelitian ini didapatkan bahwa NaOH 10 N lebih optimum untuk menghilangkan H2S dimana kandungan H2S di dalam NaOH 10N sebesar 307 ppm daripada NaOH 3 N (1790 ppm) dan NaOH 5 N (1014 ppm), NaOH berhasil digunakan untuk mengurangi H2S dari hasil produksi biogas

Towards an online-coupled chemistry-climate model: evaluation of trace gases and aerosols in COSMO-ART

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