Judul: Pembuatan dan Pencirian Plastik Biodegradabel Tepung Singkong-Umbi Porang
Abstrak: Cassava and porang tubers are polymeric material from agricultural biomass in the form of polysaccharide that can be used as raw material in the manufacture of biodegradable plastics. Plastic was made of cassava flour and combined with porang flour with glycerol and sorbitol as plasticizer. The plastics were prepared from cassava flour:porang:plasticizer with compositions 95:0:5, 70:25:5, 65:25:10, and 60:25:15. The analyses were on density, tensile strength, water vapor permeability, morphological, thermal, and functional groups. Glucomannans on porang flour increased the density and tensile strength of the biodegradable plastic produced. Water vapor permeability decreased with the addition of porang in the composition. The morphological observation showed that there was insufficient homogeneity properties. Sorbitol as plasticizer produced plastic with higher elongation than glycerol. Functional group analysis showed physical interaction.
Keyword: biodegradable plastic, cassava, porang.

Judul: Produksi Plastik Komposit dari Pencampuran Tapioka dan Onggok Termoplastis dengan HDPE.
Abstrak: Plastic is one of synthetic polymer which globally applicated because of its advantages. However, many problems emerged when plastic was discarded which cause serious environmental pollution because it can not be degraded, while its utilization increases year to year. Development of starch-based biodegradable plastic can be one alternative to solve this problem and expected to increase the added value of local agricultural products. This research aims are to study the production of composite biodegradable plastic using blending method of natural (tapioca and cassava bagasse) and synthetic (HDPE) polymers; and to analyze mechanical, thermal, and biodegradability characteristics of the composite plastic. The research was preceed with preparation and characterization of tapioca and cassava bagasse as composite plastic materials. It was followed with preparation of thermoplastic starch by adding plasticizers. Water is added up to 25% concentration of material total mass, while glycerol is added in 15% and 20% concentration. Compatibilized HDPE was made by adding 0,1% of dicumyl peroxyde and 1% of maleic anhydride in HDPE resin. The last step is processing composite plastic using blending method of thermoplastics starch and compt.HDPE in 20% and 80% ratio. Composite plastic then evaluated for its mechanical, thermal, and biodegradability characteristics. Based on quality requirement, tapioca has good quality appropriate with SNI 01-3451-1994. Result of characterization showed that cassava bagasse has high fiber content up to 33,80%. Based on the results of mechanical properties testing, it is known that compt.HDPE-tapioca with the addition of 15% glycerol has a tensile strength close to HDPE resins, as well as the elongations value. Thermal properties testing showed that the addition of 20% natural polymers in blending process gave insignificant influence. The results of biodegradability examination showed that composite plastics are capable to be degraded by microorganism. In qualitative examination, it can be seen from the growth of the fungi in some parts of the sample surface. In quantitative examination using enzymes, percentation of compt.HDPE-cassava bagasse weight loss was larger than compt.HDPE-tapioca. This is influenced by the use of α-amylase and cellulase in compt.HDPE-cassava bagasse so that the total glucose results higher, which means more degradable.
Keyword: 

Judul: Analisis Interdependensi Indeks Saham Konvensional dan Syariah Negara-Negara Anggota OKI terhadap Kondisi Keuangan Global
Abstrak: Sistem keuangan dunia semakin terintegrasi seiring dengan melesatnya kemajuan teknologi informasi dan komunikasi. Selain berbagai dampak positif yang ditimbulkan, meluasnya jangkauan sistem keuangan juga menyebabkan pasar keuangan rentan tertular krisis yang terjadi di suatu negara. Penelitian ini bertujuan untuk menganalisis interdependensi indeks saham konvensional dan syariah negara-negara anggota Organisasi Kerjasama Islam terhadap penguatan fundamental ekonomi Amerika Serikat dan krisis lira Turki pada tahun 2018 dengan menggunakan data harga penutupan harian dari indeks saham konvensional dan syariah dari tahun 2016 hingga 2018. Penelitian ini menggunakan analisis multiscale correlation contagion test. Hasil analisis menunjukkan bahwa Malaysia dan Indonesia menjadi dua negara yang paling terpengaruh terhadap penguatan fundamental ekonomi Amerika Serikat karena hubungan perdagangan yang kuat dengan negara tersebut. Sementara itu Bahrain, Arab Saudi, Kuwait, dan Oman terkena pengaruh krisis lira Turki pada tahun 2018 akibat hubungan perdagangan terhadap Turki dan negara lain di regional Timur Tengah. Qatar menjadi satu-satunya negara yang tidak terkena pengaruh penguatan fundamental ekonomi Amerika Serikat dan krisis lira Turki karena memiliki pendapatan per kapita tertinggi di dunia.
Keyword: interdependensi, krisis, multiscale correlation contagion test