Pengaplikasian Lumpur Sidoarjo Kadar Tinggi Pada Mortar Dan Beton

Berbagaipenelitian mengenai pemanfaatan material lumpur Sidoarjo, khususnya sebagai material pengganti semen (pozzolan) telah dilakukan. Penelitian ini berfokus pada penggunaan lumpur Sidoarjo dengan kadar yang tinggi, yaitu >50%, serta membandingkan hasil tersebut dengan fly ash. Analisa terhadap materialdilakukan menggunakan XRF (X-Ray Flouresence) untuk mengetahui karakteristik dari material tersebut. Analisa juga dilakukan terhadap pengaruh ukuran butiranmenggunakan PSA (Particle Size Analysis).Lumpur dilakukan treatment dari pengeringan, pembakaran hingga digiling menggunakan bar-mill dengan lama penggilingan bervariasi untuk mendapatkan ukuran butiran berbeda. Presentase kadar yang digunakan adalah 50%, 55% dan 60% dari total cementitious material. Mortar dan beton digunakan ukuran 5x5x5 cm3 dan 15x15x15 cm3 lalu dilakukan pengujian berupa kuat tekan, workability dan setting time. Hasil menunjukkan semakin halus ukuran butiran, semakin tinggi kuat tekan dan workability-nya. Diantara kadar 50%-60% penggantian semen dengan lumpur Sidoarjo, kadar 50% merupakan yang paling efektif.Pada beton dengan lumpur Sidoarjo menghasilkan slump test sebesar 8,5 cm dengan kuat tekan 34,07 MPa pada umur 37 hari

Pengaruh Konsistensi Fly Ash Terhadap Sifat - Sifat Mortar Hvfa

Fly ash merupakan hasil dari pembakaran batubara banyak digunakan sebagai bahan pengganti semen. Keuntungan penggunaan fly ash pada beton segar ialah kehalusan dan bentuk partikel fly ash yang bulat dapat meningkatkan workability, serta mengurangi terjadinya bleeding dan segregasi. Permasalahan yang sering dihadapi dalam penggunaan fly ash ini adalah kemampuan untuk mengontrol mutu fly ash yang dihasilkan.Fly ash berwarna abu-abu hingga kehitaman warna kehitaman karena adanya karbon, hal ini disebabkan pembakaran yang tidak sempurna. Juga dari penelitian lain disebutkan bahwa kandungan dari fly ash dipengaruhi dari asal batu bara, teknik pembakaran batu bara, kandungan mineral, metode pengumpulan, lama waktu penyimpanan, dan periode pengambilan sampel.Oleh karena itu dapat disimpulkan bahwa, perbedaan waktu pengambilan fly ash memungkinkan terjadinya perbedaan antara masing-masing fly ash. Dalam penelitian ini kami ingin melihat konsistensi dari setiap fly ash yang kami ambil dengan waktu yang berbeda-beda. Kandungan mineral yang terdapat dalam fly ash bervariasi, dan variasi ini tentu bisa menyebabkan perbedaan pada kualitas dan mutu beton yang dihasilkan. Variasi fly ash yang ada dapat dilihat dari kandungan kimia yang ada, kehalusan, dan loss on ignition (LOI). Kualitas dari fly ash dapat dengan mudah ditentukan melalui pengukuran nilai pH fly ash.Dalam penelitian ini menggunakan campuran mortar high volume fly ash (HVFA) dimana menggunakan penggantian semen hingga 50%

Ekstrasi Senyawa Antibakteri Dari Diatom Chaetoceros Gracilis Dengan Berbagai Metode

Extraction of Antibacterial Compound from Diatom Chaetoceros gracilis WithDifferent Methods. Diatom is phytoplankton which is commonly found in off shore.Chaetoceros produce antibacterial which inhibit some bacteria. This research was donein 3 steps. At first, Chaetoceros gracilis was cultivated in temperate controlled roomwith lighting 24 hours. The culture was harvested on 14 days, then it was dried andweighted. The second step, biomass was disrupted by different method such as sonicator,glass beads, and undisrupting. Then the biomass was maserated, filtrated, and evaporated.The crude extracts were tested to pathogen bacterial. The third step, the extraction wasconducted using hexana (non polar solvent), ethyl acetate (semi polar solvent), andmethanol (polar solvent). The crude extracts were tested to the pathogenic bacteria.The result showed that the produce cell disruption antibacterial activity by sonicator.The biggest inhibition zone was obtained by hexana but produced lower yield

MP-13 Antibody Response to Avian Influenza Vaccination in Small-Scale Duck Farming in Mojokerto District, East Java

Commercial duck farming in Indonesia is practiced either as a nomadic way (moving around) or as an intensified settled system. Since the emergence of Highly Pathogenic Avian Influenza (HPAI) H5N1 subtype clade 2.1.3 in Indonesia in 2003, ducks acted as a reservoir (carrier) without showing clinical signs. In late 2012 the new HPAI H5N1 clade 2.3.2 was introduced which caused high duck mortality, especially in young ducks. Nomadic ducks have a high risk of developing and spreading Avian Influenza (AI). In addition to this high risk, there are many duck farmers who do not practice proper AI vaccination, to achieve protective immunity. One of the measures to control AI is by administering scheduled vaccinations. The objective of this study was to investigate the increase of AI antibody titer in ducks after vaccination and to identify the best timing for vaccination

An investigation of the mechanisms for strength gain or loss of geopolymer mortar after exposure to elevated temperature

When fly ash-based geopolymer mortars were exposed to a temperature of 800 °C, it was found that the strength after the exposure sometimes decreased, but at other times increased. This paper shows that ductility of the mortars has a major correlation to this strength gain/loss behaviour. Specimens prepared with two different fly ashes, with strengths ranging from 5 to 60 MPa, were investigated. Results indicate that the strength losses decrease with increasing ductility, with even strength gains at high levels of ductility. This correlation is attributed to the fact that mortars with high ductility have high capacity to accommodate thermal incompatibilities. It is believed that the two opposing processes occur in mortars: (1) further geopolymerisation and/or sintering at elevated temperatures leading to strength gain; (2) the damage to the mortar because of thermal incompatibility arising from non-uniform temperature distribution. The strength gain or loss occurs depending on the dominant process

Correlation of cell growth and heterologous protein production by Saccharomyces cerevisiae

With the increasing demand for biopharmaceutical proteins and industrial enzymes, it is necessary to optimize the production by microbial fermentation or cell cultures. Yeasts are well established for the production of a wide range of recombinant proteins, but there are also some limitations; e.g., metabolic and cellular stresses have a strong impact on recombinant protein production. In this work, we investigated the effect of the specific growth rate on the production of two different recombinant proteins. Our results show that human insulin precursor is produced in a growth-associated manner, whereas alpha-amylase tends to have a higher yield on substrate at low specific growth rates. Based on transcriptional analysis, we found that the difference in the production of the two proteins as function of the specific growth rate is mainly due to differences in endoplasmic reticulum processing, protein turnover, cell cycle, and global stress response. We also found that there is a shift at a specific growth rate of 0.1 h(-1) that influences protein production. Thus, for lower specific growth rates, the alpha-amylase and insulin precursor-producing strains present similar cell responses and phenotypes, whereas for higher specific growth rates, the two strains respond differently to changes in the specific growth rate

ON THE DEVELOPMENT OF HIGH VOLUME VOLCANIC MUD MORTAR AND CONCRETE

The Thirteenth East Asia-Pacific Conference on Structural Engineering and Construction (EASEC-13), September 11-13, 2013, Sapporo, Japan