Experimental analysis of tribological performance of modified jatropha oil enriched with nanoparticle additives for machining application

The intensified developments of the vegetable-based metalworking fluids have been growing rapidly due to the environmental and health issue of the utilization of the mineral based oil. The vegetable oils are a great potential substitution of the mineral based oil which has been explored in recent years due to their high biodegradability, renewability and low toxicity in comparable with mineral oil. Non-edible vegetable oil had attracted an attention of the researches in contrast with edible oil which significantly compete with the human food supply. The main focus of this study was to evaluate a new formulation of vegetable-based nanofluid from chemically modified jatropha oil (MJO) blended with hexagonal boron nitride (hBN), graphene and copper oxide (CuO) nanoparticles at 0.05 wt.% concentration. The physicochemical testing was carried out in term of kinematic viscosity, viscosity index and flash point and was compare with commercial synthetic ester (SE). The analysis of MJO mixed with nanoparticles in the perspective of it tribological has been performed through a four ball tribo testing to determine the coefficient of friction, mean wear scar diameter, friction torque, surface roughness and volume wear rate. The results showed that the tribological performance the MJO+0.05wt.% CuO exhibit lowest value in of coefficient of friction and friction torque followed by MJO+0.05wt.% graphene, MJO+0.05wt.% hBN and SE. Nevertheless, the MJO+0.05wt.% graphene and MJO+0.05wt.% hBN provided the significant improvement by providing the lowest value of the mean wear scar diameter and surface roughness respectively. It concluded that the modified jatropha oil enriched with nanoparticles had a great improvement on their tribological performance, hence it’s a highly potential substitution of the SE for machining process

Efek Model Pembelajaran Kooperatif Tipe Group Investigation Dan Teamwork Skills Terhadap Hasil Belajar Fisika

Penelitian ini bertujuan untuk: Mengetahui perbedaan hasil belajarfisika siswa melalui model pembelajaran kooperatif tipe GroupInvestigationdengan model pembelajaran Direct Instruction. Mengetahui perbedaan hasilbelajar fisika antara kelompok siswa yang memiliki teamwork skills dibawah rata-rata dengan di atas rata-rata. Mengetahui interaksi antara modelpembelajaran dengan tingkat teamwork skills siswa dalam mempengaruhi hasil belajar siswa. Penelitian ini merupakan penelitian quasi eksperimen dengan desain faktorial 2x2. Populasi penelitian ini adalah seluruh siswakelas X. Sampel dalam penelitian ini dilakukan secara cluster randomsebanyak dua kelas, dimana kelas pertama sebagai kelas eksperimenditerapkan model pembelajaran kooperatif tipe Group Investigation dankelas kedua sebagai kelas kontrol diterapkan model pembelajaran DirectInstruction. Instrumen yang digunakan dalampenelitian ini yaitu instrumentes hasil belajar fisika dalam bentuk uraian sebanyak 8 soal dan insrumenobservasi teamwok skills yang telah dinyatakan valid dan reliabel. Datadianalisis menggunakan analisis Anava dua jalur. Dari hasil penelitian dapatdisimpulkan bahwa: Hasil belajar fisika pada model kooperatif tipe groupinvestigation lebih tinggi dibandingkan model direct interuction. Hasilbelajar fisika pada kelompok siswa yang memiliki tingkat teamwork skills diatas rata-rata lebih tinggi dibandingkan di bawah rata-rata. Terdapatinteraksiantara model pembelajaran dengan tingkat teamwork skills siswa dalammempengaruhi hasil belajar siswa. Model pembelajaran kooperatif tipegroup investigation sangat baik diterapkan pada kelompok siswa yangmemiliki teamwork skills di atas rata-rata. Sedangkan pada model directinteruction tidak perlu memperhatikan teamwork skills

Empirical Assessment of Breast Lesion Detection Capability Through an Innovative Microwave Imaging Device

This paper investigates the effect of conductivity weighting on microwave images obtained through a dedicated imaging device. MammoWave is a microwave imaging device for detection of breast lesions, operating using only two azimuthally rotating antennas without the use of matching liquids. For each breast, a set of conductivity weighted images are generated through modifying our algorithm based on Huygens principle, producing intensity maps representing the homogeneity of tissues’ dielectric properties. Subsequently, we introduce several imaging parameters (i.e. features) to quantify the non-homogenous behaviour of the image. Through empirical investigation on 103 breasts, we can verify that a selection of these features could allow distinction between breasts with radiological findings (WF), i.e. with benign or malign lesions, and breasts with no radiological findings (NF). Statistical significance was set at p<0.05.We obtained single features Area Under the receiver operating characteristic Curves (AUCs) spanning from 0.65 to 0.68. Significantly, we achieve AUCs of up to 0.77 when considering dense breasts only, which tend to cause detection limitations in mammography exams

Prevalence and public health implications of the microbial load of abused Naira notes

A hundred and forty (140) pieces of abused Naira notes were randomly and aseptically collected in Kano metropolis and examined microbiologically for the load and type of microorganisms (bacteria and fungi) using swab-rinse and standard plate count techniques. The mean average bacterial counts on the notes ranged between 3.59 x 102 cfu/ml and 1.29 x 105 cfu/ml while fungal counts ranged between 3.24 x 102 cfu/ml and 1.59 x 106 cfu/ml. The lowest and highest counts for both bacteria and fungi were found in the N500 and N5 abused naira denominations respectively. The bacteria isolated include the genera of Bacillus, Brucella, Clostridium, Corynebacterium, Listeria, Micrococcus and Staphylococcus while fungi include the genera of Aspergillus, Fusarium, Mucor, Penicillium and Rhizopus. There was no recovery of both bacteria and fungi in the control. The implications of the results have been discussed. Keywords: Microbiological load, abused naira notes, public health, Kano

Synthesis and Physicochemical Properties of Copper (II) Complex with a Schiff base Derived from 2 – Hydroxy – 1 – naphthaldehyde and Ethylenediammine

Synthesis of Copper (II) complex with a Schiff base derived from the condensation of 2 – hydroxyl-1-naphthaldehyde and ethylenediammine was carried out. Solubility, melting/decomposition temperature, molar conductance, potentiometric as well as uv-visible spectrophotometric studies were carried out. The pKa of the Schiff base was determined potentiometrically and checked using ORIGIN 50 method. Potentiometric studies revealed 1:1 metal to ligand ratio. Job’s method of continuous variation also revealed 1:1 metal to ligand ratio. Molar conductance measurements showed that the complex is non electrolyte with very high stability constant value. Gibb’s free energy determination showed that the complex is very stable as shown by the high decomposition temperature measurements.Keywords: Complex, Potentiometry, Schiff base, Stability constan

Antifungal Profiles of Extracts of Vitellaria paradoxa (Shea-Butter) Bark

The antifungal profiles of the bark of Vitellaria paradoxa were examined against clinical isolates of Aspergillus niger, Aspergillus flavus, Epidermophyton floccosum, Microsporum audouinii and Trichophyton mentagrophytes. Decoction method was used for the extraction of the active substances from the plant bark with cold and hot water and ethanol as extraction solvents. Agar dilution method was used in the antifungal susceptibility studies while the Minimum Inhibitory Concentration (MIC, mg/ml) and Minimum Fungicidal Concentration (MFC, mg/ml) of the ethanolic extract were determined. Generally, the ethanolic extract was the most effective, followed by the hot aqueous extract. The cold aqueous extract was the least effective against all the test fungi. All the extracts exhibited greater antifungal activity against the dermatophytes than the Aspergillus sp. Growth of T. mentagrophytes was completely inhibited by both the hot aqueous and ethanolic extracts. The similarity between the low values of the MIC and MFC obtained revealed that the plant bark possesses potent fungicidal components against the test isolates. The rate of kill study showed that with 200mg/ml of the ethanolic extract, 106 spores/ml of the Aspergillus sp. were reduced by over 50% while spores of T. . mentagrophytes were completely killed after 60 minutes contact time. This study therefore suggests that the bark of V. paradoxa could contain high concentrations of biocidal substances against the dermatophytes

Effect of tetraoctylphosphonium bromide (TOPBR) clay composition on polyvinylidene fluoride (PVDF) nanocomposite ultrafiltration membrane

Nanocomposite membranes containing polyvinylidene fluoride (PVDF) and tetraoctylphosphonium bromide clay (TOPBr) were prepared by phase inversion method. Different TOPBr and PVDF contents were used in order to investigate the effect of TOPBr clay composition on the membrane properties. The morphology of PVDF/TOPBr nanocomposite ultrafiltration (UF) membrane was characterized by scanning electron microscopy (SEM) and hydrophilicity of the nanocomposite membrane was evaluated in terms of water content, porosity and pure water flux (PWF). The results revealed that the increasing of TOPBr clay content produced more porous nanocomposite membrane due to the formation of many finger like pores and microvoids. The hydrophilicity of the membranes was strongly enhanced by increasing the contents of TOPBr clay.Keywords: Polyvinylidene fluoride; Nanocomposite membrane; Ultrafiltration; Hydrophilicity; Cla

Pembuatan Aplikasi Tata Ruang Tiga Dimensi Gedung Serba Guna Menggunakan Teknologi Virtual Reality [Studi Kasus : Graha ITS Surabaya]

Pada bidang pemasaran dan periklanan di Perusahaan saat ini cenderung menampilkan Gambar 2D dalam penyampaian informasi kepada pengguna. Gambar 2D yang sering kita tahu berfungsi sebagai media penyampaian informasi. Misal informasi tentang suatu tata ruang, namun informasi yang dapat disajikan hanya dari sisi-sisi tertentu saja. Untuk itu, dibutuhkan tampilan visual yang dapat mengGambarkan tata ruang suatu bangunan dalam bentuk 3D. Sehingga seseorang dapat mengetahui informasi suatu ruangan dari berbagai sisi. Karena teknologi semakin canggih, diharapkan aplikasi yang dibuat dapat dinikmati semua kalangan. Pada pembuatan tugas akhir, penulis membuat tata ruang gedung yang dapat ditampilkan dalam bentuk 3D menggunakan teknologi 3D yaitu virtual reality. Virtual reality merupakan ruang digital dimana data input sudah diprogram sebelumnya. Pada pengerjaan tugas akhir ini menggunakan tool augmented reality adalah penggabungan antara objek-objek di dunia nyata dan dunia maya yang berjalan secara interaktif karena saling terintegrasi. Dengan memberikan input berupa marker maka output yang dihasilkan berupa tampilan 3D yang sesuai. Lokasi gedung yang dibuat yaitu Gedung Graha ITS. Penulis mengharapkan, aplikasi dapat digunakan untuk menunjukkan tata ruang dan contoh dekorasi kegiatan di Gedung Graha ITS secara akurat dan interaktif

Rancang Bangun Peta Virtual 3D Jurusan Teknik Informatika Institut Teknologi Sepuluh Nopember dengan Unity3D Engine

Pengenalan akan suatu organisasi atau Perusahaan merupakan suatu awal yang penting sebelum dimulainya kerjasama terhadap organisasi tersebut. Berbagai informasi dibutuhkan untuk mendukung kredibilitas organisasi, beberapa diantaranya yaitu brand, profil organisasi, laporan keuangan, dan proses bisnis. Dengan adanya proses bisnis yang digambarkan secara jelas, pihak-pihak ekstern organisasi dapat mengenali kegiatan-kegiatan yang dilakukan oleh organisasi tersebut yang nantinya berdampak pada tingkat pemahanan terhadap organisasi. Sebuah peta virtual tiga dimesi (3D) bangunan organisasi yang dilengkapi dengan simulasi proses bisnis dapat menjadi media pengenalan akan suatu organisasi. Dengan adanya fasilitas tersebut, pihak-pihak ekstern organisasi dapat secara mandiri mencoba untuk ikut serta dalam simulasi proses bisnis organisasi. Jurusan Teknik Informatika Institut Teknologi Sepuluh Nopember merupakan salah satu jurusan informatika terkemuka di Indonesia. Sejauh ini Jurusan Teknik Informatika ITS dikenal melalui kualitas lulusan yang baik dan dari brand jurusan, namun kebanyakan pihak eksternal kurang mengetahui proses bisnis yang ada didalamnya. Diharapkan dengan diterapkannya peta virtual 3D yang diimplementasikan dalam sebuah web, pihak eksternal dapat lebih mengenali proses bisnis yang ada dalam Jurusan Teknik Informatika ITS secara lebih baik yang nantinya berimplikasi pada terwujudnya kerjasama terhadap Jurusan Teknik Informatika ITS