Karakteristik Lem Dari Tulang Ikan Dengan Habitat Yang Berbeda (Payau, Tawar, Laut)

Limbah tulang ikan dalam industri perikanan saat ini belum dimanfaatkan secara optimal. Pemanfaatan limbah sisa olahan ikan tersebut perlu dikembangkan sehingga tidak menjadi sumber pencemaran lingkungan. Salah satu inovasi pemanfaatan limbah tulang ikan yaitu dapat dijadikan lem ikan. Lem ikan adalah bahan perekat yang berasal dari bagian ikan seperti kulit atau tulang, dan merupakan hasil ekstraksi kolagen dengan menggunakan pelarut bersifat asam. Penelitian ini bertujuan untuk mengetahui pengaruh perbedaan jenis tulang ikan yang digunakan terhadap karakteristik dan mutu lem ikan yang dihasilkan. Materi yang digunakan dalam penelitian ini adalah tulang ikan bandeng, nila dan manyung yang masing-masing didapatkan dari sentra pengolahan Bandeng Semarang Indah, PT Aquafarm Nusantara Semarang, dan sentra pengasapan Bandarharjo. Pada penelitian ini tulang ikan diekstraksi menggunakan larutan asam asetat 5% selama 4 jam dengan suhu 65 – 70°C. Parameter pengujian dalam penelitian ini adalah keteguhan rekat, kerusakan kayu, viskositas, derajat keasaman (pH), dan kadar air. Penelitian ini dilakukan dengan metode percobaan laboratoris menggunakan rancangan dasar acak lengkap dengan tiga kali pengulangan. Hasil penelitian menunjukkan bahwa penggunaan tulang ikan manyung sebagai bahan baku pembuatan lem ikan merupakan perlakuan terbaik karena karakteristik lem ikan yang dihasilkan memenuhi SNI 06-6049-1999 tentang Polivinil Asetat untuk Pengerjaan Kayu dengan hasil: kerusakan kayu 68.13%, viskositas 6.14 poise, pH 4.45, dan kadar air 54.84%. Nowadays, fishbone waste in fisheries industries are not yet used optimally. Waste utilization from fish processing need to be developed so that it won\u27t become environmental contamination. An innovation to utilize fishbone waste is to make it to be fish glue. Fish glue is an adhesive from parts of fish such as skin and fishbone and is the result from collagen extraction process by using acidic solvent. The main purpose of this research is to find out the effect of different types of fishbone toward the fish glue\u27s characteristic and quality. The used materials in this research are milkfish bones, tilapia bones, and seawater catfish bones which obtained from Semarang Indah Milkfish processing center, PT Aquafarm Nusantara Semarang, and Bandarharjo smoked fish center. In this research fishbones were extracted using acetic acid 5% for 4 hours in 65 – 70°C. The testing parameters in this research are bonding strength, timber damage, viscosity, pH, and water content. This research was conducted with a laboratory experiment using a completely basic randomized design with three replications. The result of this research showed that by using seawater catfish bones as the glue\u27s raw material, it shows the best result and the characteristic meet Indonesia\u27s National Standart (SNI) 06-6049-1999 about Polivinyl Acetat for Wood Processing which are: timber damage 68.13%, viscosity 6.14 poise, pH 4.45, and water content 54.84%

Optical properties of absorbing and non-absorbing aerosols retrieved by cavity ring down (CRD) spectroscopy

International audienceApplication of cavity ring down (CRD) spectrometry for measuring the optical properties of pure and mixed laboratory-generated aerosols is presented. The extinction coefficient (?ext), extinction cross section (?ext) and extinction efficiency (Qext) were measured for polystyrene spheres (PSS), ammonium sulphate ((NH4)2(SO4), sodium chloride (NaCl), glutaric acid (GA), and Rhodamine-590 aerosols. The refractive indices of the different aerosols were retrieved by comparing the measured extinction efficiency of each aerosol type to the extinction predicted by Mie theory. Aerosols composed of sodium chloride and glutaric acid in different mixing ratios were used as model for mixed aerosols of two non-absorbing materials, and their extinction and complex refractive index were derived. Aerosols composed of Rhodamine-590 and ammonium sulphate in different mixing ratios were used as model for mixing of absorbing and non-absorbing species, and their optical properties were derived. The refractive indices of the mixed aerosols were also calculated by various optical mixing rules. We found that for non-absorbing mixtures, the linear rule, Maxwell-Garnett rule, and extended effective medium approximation (EEMA), give comparable results, with the linear mixing rule giving a slightly better fit than the others. Overall, calculations for the mixed aerosols are not as good as for single component aerosols. For absorbing mixtures, the differences between the refractive indices calculated using the mixing rules and those retrieved by CRD are generally higher

Induksi Pematangan Gonad Ikan Patin Siam Pangasianodon Hypopthalmus (Sauvage, 1878) Jantan Dengan Pemberian Ekstrak Cabe Jawa Piper Retrofractum Vahl. Melalui Pakan [Induction on Gonadal Maturation of Male Striped Catfish Pangasianodon Hypopthalmus (Sauvage, 1878) Using Javanese Long Pepper Extract Piper Retrofractum Vahl. Enriched Feed]

Cabe jawa merupakan salah satu tanaman yang memiliki efek hormonal sebagai afrodisiak. Penelitian ini bertujuan un-tuk mengevaluasi pemberian ekstrak cabe jawa (ECJ) melalui pakan terhadap akselerasi pematangan gonad ikan patin siam jantan. Perlakuan yang diberikan meliputi ECJ dengan dosis 37,5 dan 187,5 mg kg ikan-1 hari-1, dibandingkan dengan 17-a Metiltestosteron (50 ^g kg ikan-1 minggu-1) dan kontrol selama 8 minggu. Perlakuan ECJ menunjukkan in-deks kematangan gonad lebih tinggi dibandingkan kontrol sejak minggu ke-2 (p0,05). Perlakuan ECJ 187,5 mg kg ikan'1 hari-1 meningkatkan performa reproduksi dan kualitas sperma ikan patin siam jantan

Survival Wolio Language in Adulthood in Baubau City: Sociolinguistic Study

The article is the result of a study that discusses the survival of Wolio language in adolescence in Baubau City. The focus of this study is adults aged between 17-20 years. As for the domain of the question is the family, association, education, government, transactions, neighbors, religion, culture, art. In this research, the approach used is the sociolinguistic approach. In this case, the approach (approach) of sociology, namely the study of language in the social context, which is studied is the behavior of groups rather than individual behavior. In analyzing the data is done by calculating the percentage following the calculation pattern, that is the calculation based on the number of incoming answers) The results are found Wolio language Based on the analysis shows that in the adult category the tendency of the use of Wolio language has been in the category even though on the defense side still last

Analysis of the Difference between Hydraulic Fracturing and Flow Channel Fracturing

As time goes by, there will be a decline in formation productivity, as reflected in the decline in the rate of oil production from production wells. The decline in the rate of production was caused by many things such as a decrease in reservoir pressure, also formation damage. Where damage to the formation will result in a decrease in rock permeability. The decrease in rock permeability is caused by the blockage of rock pores due to the invasion of solids and drill mud filtrate, cementing, fluid fluids or previous stimulation. Besides the small rate of oil production can also be caused by the low natural permeability of rocks. With the decreasing productivity of the formation, it is necessary to make efforts to increase the productivity of the formation again, where one of them is by the method of hydraulic fracture stimulation. In this analysis, we will discuss the difference between conventional stimulation methods and flow channel fracturing. Flow channel fracturing is a fracturing process by making a network around proppant granules to form proppant pillar, so that a path is formed for the fluid to flow more easily. What distinguishes between conventional hydraulic fracturing with flow channel fracturing is the resulting fracture form, fracturing fluid injection pattern, and the amount of proppant used

Cloud Condensation Nuclei properties of model and atmospheric HULIS

Humic like substances (HULIS) have been identified as a major fraction of the organic component of atmospheric aerosols. These large multifunctional compounds of both primary and secondary sources are surface active and water soluble. Hence, it is expected that they could affect activation of organic aerosols into cloud droplets. We have compared the activation of aerosols containing atmospheric HULIS extracted from fresh, aged and pollution particles to activation of size fractionated fulvic acid from an aquatic source (Suwannee River Fulvic Acid), and correlated it to the estimated molecular weight and measured surface tension. A correlation was found between CCN-activation diameter of SRFA fractions and number average molecular weight of the fraction. The lower molecular weight fractions activated at lower critical diameters, which is explained by the greater number of solute species in the droplet with decreasing molecular weight. The three aerosol-extracted HULIS samples activated at lower diameters than any of the size-fractionated or bulk SRFA. The Köhler model was found to account for activation diameters, provided that accurate physico-chemical parameters are known

Temperature Dependent Zero-Field Splittings in Graphene

Graphene is a quantum spin Hall insulator with a 45 $\mu$eV wide non-trivial topological gap induced by the intrinsic spin-orbit coupling. Even though this zero-field spin splitting is weak, it makes graphene an attractive candidate for applications in quantum technologies, given the resulting long spin relaxation time. On the other side, the staggered sub-lattice potential, resulting from the coupling of graphene with its boron nitride substrate, compensates intrinsic spin-orbit coupling and decreases the non-trivial topological gap, which may lead to the phase transition into trivial band insulator state. In this work, we present extensive experimental studies of the zero-field splittings in monolayer and bilayer graphene in a temperature range 2K-12K by means of sub-Terahertz photoconductivity-based electron spin resonance technique. Surprisingly, we observe a decrease of the spin splittings with increasing temperature. We discuss the origin of this phenomenon by considering possible physical mechanisms likely to induce a temperature dependence of the spin-orbit coupling. These include the difference in the expansion coefficients between the graphene and the boron nitride substrate or the metal contacts, the electron-phonon interactions, and the presence of a magnetic order at low temperature. Our experimental observation expands knowledge about the non-trivial topological gap in graphene.Comment: Main text with figures (20 pages) and Supplementary Information (14 pages) Accepted in Phys. Rev.