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The interaction and adhesion between the fiber and matrix has a significant effect in determining the mechanical and physical behavior of fiber composites. The effect of the interface and interphase depends on several factors such as chemical composition (functional groups), molecular structure characteristics (branching, molecular weight distribution, cross-linking), and details of its physical state (above or below T g , nature and degree of crystallinity). Natural fibers have complex and varying chemical structures that have uneven surface topographies. This creates difficulties in using single fiber composite testing to accurately evaluate the interfacial shear strengths, except for comparisons. A review of our interphase related research in natural fiber composites is presented.When using coupling agents it is well known that the tensile and flexural strengths increase dramatically in natural fiber reinforced composites. However, in the case of modulus, the results are more complex. For two ethylene-propylene impact copolymers, the uncoupled systems had much higher Young's moduli than the coupled systems. The dynamic storage moduli of the uncoupled impact polymers were higher than the coupled composites at temperatures up to about 50 8C. At higher temperatures the presence of the coupling agent resulted in higher storage moduli. Transcrystallinity may play an important role in this phenomenon. Creep and other long-term properties are also affected by the quality of the interphase, although the level of improvement decreases with an increase in the molecular weight of the matrix polymer. Coupling agents reduced the rate of water absorption and the moduli were less affected in blends with a higher concentration of coupling agents.

The interaction and adhesion between the fiber and matrix has a significant effect in determining the mechanical and physical behavior of fiber composites. The effect of the interface and interphase depends on several factors such as chemical composition (functional groups), molecular structure characteristics (branching, molecular weight distribution, cross‐linking), and details of its physical state (above or below Tg, nature and degree of crystallinity). Natural fibers have complex and varying chemical structures that have uneven surface topographies. This creates difficulties in using single fiber composite testing to accurately evaluate the interfacial shear strengths, except for comparisons. A review of our interphase related research in natural fiber composites is presented. When using coupling agents it is well known that the tensile and flexural strengths increase dramatically in natural fiber reinforced composites. However, in the case of modulus, the results are more complex. For two ethylene‐propylene impact copolymers, the uncoupled systems had much higher Young's moduli than the coupled systems. The dynamic storage moduli of the uncoupled impact polymers were higher than the coupled composites at temperatures up to about 50°C. At higher temperatures the presence of the coupling agent resulted in higher storage moduli. Transcrystallinity may play an important role in this phenomenon. Creep and other long‐term properties are also affected by the quality of the interphase, although the level of improvement decreases with an increase in the molecular weight of the matrix polymer. Coupling agents reduced the rate of water absorption and the moduli were less affected in blends with a higher concentration of coupling agents.

ABSTRAKTujuan penelitian ini adalah mempelajari pengaruh intensitas daya dan waktu reaksi terhadap rendemen dan karakteristik gelombang mikro ( ). Minyak jelantah diperoleh dari pabrik kerupuk yang berlokasi di Sukarame, Bandar Lampung. Reaksi pembuatan biodiesel dilakukan menggunakan gelas erlenmeyer yang dipanaskan di dalam oven berdaya 399 watt dan frekuensi 2.450 MHz yang telah dilengkapi dengan pengaduk listrik berkecepatan 1446 RPM. Penelitian menggunakan rancangan acak faktorial dengan dua faktor. Kedua faktor adalah intensitas daya gelombang mikro dengan tiga taraf [(30, 50, dan 70%) dan waktu reaksi, juga dengan tiga taraf (30, 60, dan 120 detik). minyak jelantah pada perbandingan molar minyak jelantah terhadap metanol 1:6. Parameter yang dianalisis meliputi rendemen, bilangan asam, massa jenis, dan viskositas biodiesel. Data dianalisis menggunakan ANOVA diikuti uji beda = 5% dan = 1%. Hasil penelitian menunjukkan bahwa intensitas daya gelombang mikro dan waktu reaksi tidak berpengaruh terhadap bilangan asam, viskositas, dan massa jenis biodiesel. Biodiesel yang dihasilkan memiliki bilangan asam 2,98-4,20 mgKOH/g, massa jenis 0,87-0,88 g/mL, dan viskositas 1,9-2,0 cSt. Intensitas daya gelombang mikro dan waktu reaksi serta interaksinya berpengaruh nyata pada rendemen biodiesel. Dalam penelitian ini, tanpa memperhatikan intensitas daya gelombang mikro, waktu reaksi terbaik adalah 30 detik saat rendemen biodiesel rata-rata mencapai 91,1%. Kata kunci ABSTRACTThe purpose of this research was to study the effect of power intensity and reaction time on the yield and the characteristic using an erlenmeyer glass heated in a microwave oven with power capacity of 399 watt and frequency of 2,450 arrangements was used in this experiment. Treatment consisted of two factors, namely power intensity and reaction time. The power intensity included three levels (30, 50, and 70%). Similarly did for the reaction time (30, 60, and 120 cooking oil to methanol). Parameters to be analyzed included biodiesel yield, acid number, density, and viscosity of = 1%. The results showed that both microwave power intensity and reaction time and their interaction had no effect on the viscosity, acid number and density of produced biodiesel. Biodiesel produced has acid number of 2.98 to 4.20 mgKOH/g, density of 0.87 to 0.88 g/mL, and viscosity of 1.9 to 2 cSt. Microwave power intensity and reaction time and time of 30 seconds was adequate for microwave-assisted biodiesel synthesis with an average yield reaching 91.1%.

Abstract. Simangunsong BCH, Manurung EGT, Elias, Hutagaol MP, Tarigan J, Prabawa SB. 2020. Tangible economic value of non-timber forest products from peat swamp forest in Kampar, Indonesia. Biodiversitas 21: 5954-5960. Development of alternative economy based on non-timber forest products usage is an important means to prevent forest conversion and preserve the quality of a forest ecosystem. The main objectives of this study were to identify and calculate the economic value from tangible/marketable perspective of the non-timber forest products (NTFPs) provided by peat swamp forest in Kampar, Sumatra, Indonesia. This is one of the largest remaining peat swamp forest ecosystems in the country. Seven villages located around that forest ecosystem with total forest cover area of 201,224 ha were chosen as samples. A conversion return approach was used to estimate the economic value of non-timber forest products. The results showed 18 kinds of non-timber forest products were identified, but only seven were used commercially by community. They are jungle rubber (Hevea brasiliensis), sago (Metroxylon sp.), swiftlet nest (Aerodramus fuciphagus), honey, betel nut (Areca catechu L), Agathis resin (Agathis dammara), and pandan (Pandanus amaryllifolius Roxb.) The obtained economic value of NTFPs was very low, which was about Rp 9,367.4 (or US$0.68 ha-1 yr-1). Market development of non-timber forest products is then crucial, and the government should play an important role in promoting it in collaboration with private companies. Non-marketed non-timber forest products and various environmental services should also be taken into account to measure that peat swamp forest ecosystem value. Otherwise, concerns about the sustainability of that forest ecosystem in Indonesia due to undervaluation of forest resources will continue.

Ayam broiler (Gallus domesticus) merupakan jenis ternak yang banyak dikembangkan sebagai sumber pemenuhan kebutuhan protein hewani. Namun, karena merupakan bahan segar dan memiliki kandungan air yang tinggi, daging ayam broiler rentan terhadap kebusukan yang disebabkan oleh mikroba. Perlakuan dengan ozon dan suhu penyimpanan mampu mempertahankan kualitas daging ayam ditinjau dari kualitas fisika, kimia, dan sensoris. Penelitian ini bertujuan untuk mengetahui pengaruh perlakuan ozonisasi dan suhu penyimpanan terhadap sifat fisika, kimia, dan sensoris daging ayam broiler. Variasi waktu perendaman, yaitu 5, 10, dan 15 menit, sedangkan untuk variasi penyimpanan yaitu 10°C dan -6°C. Penelitian ini dilakukan menggunakan Rancangan Acak Lengkap Faktorial (RALF) dan analisis lanjutan menggunakan DMRT. Hasil yang didapatkan adalah perlakuan ozon dan suhu beku efektif dalam mengurangi nilai drip loss namun meningkatkan susut masak, menurunkan atribut warna, mengurangi nilai aw, mempertahankan nilai pH, mempertahankan laju kenaikan TBARS dan TVB-N mempertahankan nilai kesukaan konsumen. Perlakuan paling efektif untuk daging ayam yaitu dengan perendaman selama 15 menit dan penyimpanan dengan suhu -6°C mampu mempertahankan drip loss, aw, pH, TBARS, TVB-N, dan sensoris dari daging ayam.

<p class="abstrak">Surakarta City is one of the cities in Central Java which is vulnerable to food insecurity events, especially transient food insecurity. This is because the city of Surakarta is a disaster-prone area from flooding, strong winds and landslides. This will have an impact on nutrition and food access for the people of Surakarta City when a disaster occurs. The role of the SKPG is very important in providing information for the Surakarta City government regarding the condition of food and nutrition, so that the response to food insecurity can be right on target. The SKPG is compiled by collecting data according to categories, which are then processed for policy making from the Surakarta City government. The quality of public food consumption in Surakarta City, Central Java is still far from ideal. This is indicated by the score of the Expected Food Pattern (PPH) which was still in the range of 80.8% in 2016 which was even lower than 2014 which reached 90.3%. However, in 2019 PPH for Surakarta City was 94%, higher than the national target (92%) based on SKPG annual report of Surakarta City 2019. Apart from the low level of public awareness, the economic condition of the residents can also be the cause of this low quality of food. The decreasing purchasing power of the people is directly proportional to their ability to meet the nutritional standards of the food they consume. The problem of low quality food consumption does not only occur in Central Java, but also nationally. The facts show that Indonesia is ranked the country with the worst food nutrition in the world. This is indicated by the still high number of children under five with weight and height not according to age, which is in the range of 37%, obesity is 12%, and thinness of 11%, this has the potential to lead to greater stunting cases. The occurrence of food and nutrition insecurity is generally caused by not meeting the amount of agricultural production to meet food needs in the region. SKPG is implemented as a measure to anticipate and overcome food insecurity in Surakarta. SKPG should be able to become a guideline so that even distribution and improvement of food security can be done. Based on the explanation of these problems, it is necessary to develop a Food and Nutrition Precautions System in Surakarta City.</p><p class="abstrak"><em>Key words: Food, Nutrition, SKPG, Surakarta, Vigilance</em></p>

White chrysanthemum (Chrysanthemum morifolium Ramat.) is widely used in medicine, popular drinks and as a functional food. White chrysanthemums are often used as health care products because they contain functional compounds such as phenolic compounds and antioxidant activity. Chrysanthemum is well known in Indonesia, but it has not been utilized optimally in daily life as functional food. This research is done in order to determine the effect of drying using cabinet dryer at temperatures of 40°C, 50°C, and 60°C on physical characteristics such as color and shrinkage, chemical characteristics such as moisture content, total phenol, antioxidant activity and water activity, and sensory characteristics such as color, aroma, taste, after taste and overall as well as the amount of heat required for the drying process. This research is conducted using completely randomized design. The results show that cabinet dryer at 60°C is the best drying method. Characteristics in white chrysanthemum tea are ∆E value is 39,51; long shrinkage value is 23,65%, width shrinkage is 28,46%; water content value is 6,81%; total phenol value is 15,99%; antioxidant activity value is 87,52%; water activity value is 0,25; with color 3,93 (like), aroma 3,30 (neutral), taste 3,03 (neutral), after taste 3,33(neutral) and overall 3,23 (neutral). The heat of drying at 60°C is 2.147,295kJ.