Judul: Mempelajari pengawetan jamur merang dengan cara pendinginan
Abstrak: Jamur merang (Volvariella volvacea BULL. Quelet) me- rupakan salah satu bahan hasil pertanian yang mempunyai nilai ekonomis tinggi. Tetapi bahan ini sangat mudah ru- sak, yaitu dalam jangka waktu 24 jam tanpa perlakuan peng- awetan jamur merang akan menjadi busuk atau tudungnya mem- buka membentuk payung. Jamur merang yang telah mengalami kerusakan ini akan merosot harganya. Karena itu diperlu- kan suatu tindakan pengawetan untuk mempertahankan nilai ekonomisnya dan memperpanjang daya tahan jamur merang ter- hadap kerusakan. Salah satu cara pengawetan yang dapat dilakukan ter- hadap jamur merang adalah dengan pendinginan. Cara ini te- lah banyak dilakukan terhadap berbagai jenis sayuran lain dengan memberikan hasil yang cukup baik. Tahap-tahap yang dilakukan dalam penelitian ini meli- puti tahap pembersihan (trimming), pencucian, penirisan, "blanching", pendinginan, penirisan, pembungkusan dan pe- nyimpanan dingin. Penyimpanan dingin dilakukan di dalam sebuah lemari es yang mempunyai kisaran suhu 7° 9° с.
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Judul: Mempelajari karakteristik pengeringan  jamur merang (Volvariella volvaceae)
Abstrak: Pengeringan jamur merang dilakukan dari kadar air sampai mendekati kadar air kesetimbangan bahan dengan rikan empat perlakuan suhu, masing-masing 35 °C, 40 C, dan 50 °C, dan empat perlakuan kecepatan aliran awal membe- C, 45 udara, yaitu 1.0 m/dt, 1.5 m/dt, 2.0 m/dt, dan 2.5 m/dt. Jamur merang setebal sebelum dikeringkan, dipotong dengan arah horisontal 2 sampai 4 milimeter, dan direndam dalam larutan natrium meta bisulfit 2000 ppm, kemudian dibagi dalam dua bagian. Bagian pertama mendapat perlakuan blansir dengan air panas (80 °C 90 °C) selama lima menit. Pengamatan awal, kecepatan yang dilakukan meliputi berat jamur merang aliran udara pengering, kadar air awal, penurunan berat selama proses pengeringan, berat jamur merang kering setelah menyerap air, organoleptik jamur merang kering, suhu udara pengering dan lingkungan. Penentuan kadar air awal jamur merang dilakukan dengan metoda oven pada suhu 105 °C. Setelah pengolahan data dari percobaan yang menghasilkan kadar air dan laju pengeringan, maka proses selanjutnya menentukan nilai kadar air kesetimbangan (Me) dan koefisien pengeringan (K) dengan memanfaatkan sebuah program komputer. Program komputer yang dibuat mengacu pada persamaan model datar tak terbatas dan persamaan model bola. Keabsahan program <omputer dibuktikan dengan uji kebaikan ..dst
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Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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