Utilization of Poly(methyl Methacrylate) Rejection Blended with Acrylonitrile Butadiene Styrene Resins and the Effect on Product Properties

PMMA is one of the main raw materials for the injection molding process in the lens industries. Since this process requires extremely careful techniques to obtain lens with the best quality, it leads to a high rate of product rejection. These rejected products do not only pose an issue for the industrial environment and require storage space, their price also falls significantly. Among the solutions to this problem is to reuse the rejected products as substitute materials for the manufacture of another product's part such as lamp holders. This process reuses rejected PMMA-containing products in the ABS base polymer industries so as to generate PMMA-containing products with better physical properties. In this experiment, 10 to 40 % (w/w) of rejected PMMA was blended with ABS resins. The monomer content in the ABS resins was analyzed by NMR. Moreover, the mechanical, thermal, and morphological properties of the blended products were also examined. The NMR analysis showed that the resin contained 21.6 % butadiene monomer, in which its value was higher than the value required for materials with high-impact class application. The blend of resins and rejected PMMA (10-30% w/w) could increase the tensile strength value and decrease Izod impact strength and elongation percentage. The morphological analysis showed that this increased PMMA content may also result in widespread brittle areas. Since the blend was designed without compatibilizers, the DSC analysis indicated that the resulting blend in any ratios was not completely miscible. It was revealed that ABS resins containing 10% PMMA was the best blend for the polymer engineering application and this blend still had adequate properties and elastomer content required

Analisis Hubungan Panjang Berat Pada Ikan Hermaphrodit : Kerapu Sunu (Plectropomus Leopardus) Dan Kerapu Macan (Epinephelus Fuscoguttatus)

Penelitian ini bertujuan untuk mengeksplorasi hubungan panjang berat dua spesies ikan kerapu hermafrodit, yaitu kerapu sunu (Plectropomus leopardus) dan kerapu macan (Ephinephelus fuscoguttatus). Sebanyak 1.263 individu ikan yang terdiri dari 609 dan 654 spesies pertama dan kedua, masing-masing dikumpulkan dari perairan Wangi-Wangi dan Karang Kaledupa Taman Nasional Wakatobi selama September 2018 hingga Februari 2019. Ikan dikumpulkan secara acak yang merupakan hasil tangkapan pancing dan tombak. Hasil kedua spesies menunjukkan pola pertumbuhan alometrik (p 70%), sedangkan E. fuscoguttatus untuk kategori yang sama berada pada persentase yang lebih rendah (<50%). Langkah-langkah pengelolaan pada spesies hermafrodit dapat difokuskan pada proporsionalitas antara betina dan jantan terhadap keberhasilan reproduksi

The Influence of Poly(Lactic Acid) Addition to Thermal Properties of the Blended Polypropylene for Food Packaging Materials

The commonly used food packaging materials are made from synthetic polymers derived from petroleum. However, the use of synthetic polymers has negative impacts on the environment, because it is difficult to degrade naturally either by the biotic or abiotic process. Although their complete replacement with eco-friendly packaging films is just impossible to achieve economically, at least for a specific application like food packaging the use of bioplastics should be the future. One of the alternatives is to blend synthetic polymer for instance polypropylene (PP) with a natural polymer like poly-lactic acid (PLA). Because their mixture is an immiscible blend because they have highly different polarity, it is necessary to add a compatibilizer such as polypropylene-grafted maleic anhydride (PP-g-MAH) in order to increase the properties of its blend miscibility. The objective of this research was to study the influence of PLA addition to the thermal properties of their blend product with PP. The combinations of PP with PLA in the ratios of (80:20); (90:10); (95:5) were prepared and then characterized for their thermal property behaviour by means of TG and DSC. The results showed that increasing the amount of PLA will decrease their enthalpy significantl

Collaborative Planning on Cross-Border Service of Water Supply in Surakarta Urban Border Area, Indonesia

Recently, many planners apply collaborative planning theory in planning involving two or more parties, such as between government, private and community, including in the interregion cooperation. However, the theory has rarely been used to explain the interaction between regions in city border area, especially in the cases in Indonesia. This article discusses the case of cross-border service of water supply of the Local Water Company (PDAM-Perusahaan Daerah Air Minum) of Surakarta City into the urban border area of Sukoharjo Regency, based on collaborative planning theory. This article is written based on results of the research on the case using case study research method. The discussion concludes that the approach of collaborative planning theory used on the case is cooperative-accommodation approach. It is because PDAM of Surakarta City accommodate the cross-border region service as a reciprocal policy, as most of their water inputs come from their neighboring regions. In general, such an approach is in accordance with the need of the interacting regions, which one region needs supporting service to meet the need of their communities in water service, and another can fulfill the need based on its capacity. In this case, the concerned technical agencies, PDAM of every region interact each other directly in providing the service. The important thing, the interaction is in line with the prevailing cross-border region bureaucratic regulations and does not infringe the autonomy of every region

Sistem Identifikasi Kualitas Cuka Apel Menggunakan Kamera, Sensor Kimia, dan Metode Artificial Neural Network

Produksi apel pada tahun 2012 hingga 2014 sebesar 590.004 ton, 838.915 ton, dan 708.438 ton. Salah satu produk olahan yang dapat diciptakan dengan berbahan dasar apel adalah cuka apel. Namun untuk saat ini penilaian kualitas cuka apel dilakukan dengan pengindraan manusia dimana hal tersebut tidaklah akurat. Pada penelitian ini dilakukan perancangan sistem identifikasi kualitas cuka apel menggunakan kamera, sensor kimia, dan metode artificial neural network (ANN). Parameter yang diambil untuk pengukuran dan penentuan standar antara lain keasaman, warna, dan kadar alkohol pada cuka apel. Alat ini diuji coba pada 6 cuka apel berbeda yaitu, Bragg, Heinz, Cuka Apel Batu, Cuka Apel Kusuma, Daesang Chung Jun One, dan Cuka Apel Tahesta. Alat ini dapat menggolongkan cuka apel ke dalam 3 golongan berbeda