26 research outputs found
PENGARUH TINGKAT KEMATANGAN DAN LAMA PENGERINGAN TERHADAP MUTU BENIH GAMBAS HIBRIDA (Luffa acutangula)
No full textGambas merupakan tanaman yang dikembangbiakkan dengan biji atau benih. Benih gambas yang bermutu dapat menghasilkan tanaman gambas yang berproduksi dengan baik. Masalah-masalah yang sering dihadapi dalam teknologi produksi benih kebanyakan menjurus kepada aspek-aspek dalam bidang produksi, pengolahan, penyimpanan dan pengujian benih. Pada produksi benih gambas, sering terjadi kemunduran mutu benih yang disebabkan waktu panen dan pengeringan yang tidak tepat. Penelitian ini bertujuan untuk mengetahui pengaruh tingkat kematangan dan lama pengeringan benih terhadap mutu benih gambas hibrida. Penelitian dilaksanakan bulan Januari-Juni 2015 di PT. Benih Citra Asia Desa Rowosari Kecamatan Sumberjambe Kabupaten Jember Jawa Timur. Penelitian ini dilakukan dengan menggunakan Rancangan Acak Lengkap (RAL) Faktorial dengan 2 faktor, yaitu tingkat kematangan (K) sebagai faktor I dengan 4 taraf perlakuan yaitu K1 = pemanenan buah 55 hari setelah polinasi (hsp), K2 = pemanenan buah 65 hsp, K3 = pemanenan buah 75 hsp dan K4 = pemanenan buah 85 hsp. Faktor II adalah lama pengeringan (P) terdiri dari 3 taraf, yaitu P1 = 5 jam, P2 = 6 jam dan P3 = 7 jam. Setiap perlakuan dibuat dalam 3 ulangan. Pengamatan dilakukan pada karakter kuantitatif dengan parameter persentase kadar air, persentase daya berkecambah, bobot 1000 butir benih dan persentase vigor benih. Hasil penelitian menunjukkan perlakuan K2P2 (pemanenan 65 hari setelah polinasi dengan pengeringan 6 jam) menunjukkan hasil yang terbaik terlihat dari persentase perkecambahan sebesar 79,3%, kadar air 16,8%, bobot 1000 butir 154,44 gram dan vigor benih 0,67%
The Nutritional Composition of Red Durians from Banyuwangi, Indonesia
No full textBanyuwangi regency has red fleshed durians which grow naturally and also cannot be found in other areas because of it is an endemic species from Banyuwangi. The information about red durian nutrients compositions are not available yet, whereas those composition are important in determining of red durian nutrient composition, handling techniques, and further processes. This research was conducted to analyze the nutrient composition of eight (8) variant of Banyuwangi’s red durians, and compare the nutritional compositions of yellow and white durians which can be found around the location of red durians. The eight variants of Banyuwangi’s red durians which used in this study are Serat, Serat Pink, Musang Merah, Tallun Jeruk, Sun rice of Java, Red Horny Jameela, Red King, and Pelangi. In this research, the nutrient content in 100 g of fresh durian flesh samples for 10 parameters were analyzed, such as protein (%), fat (%), carbohydrates (%), total sugar (%), calories (cal/g), vitamin C (mg/100g), Zinc (Zn) (ppm), iron (Fe) (ppm), potassium (K) (%), and sulfur (S) (%). Furthermore, the data were analyzed descriptively. The results showed that Serat Pink durian has higher protein content than other red durians and white durians. All red durian have lower protein content than yellow durians. Tallun jeruk durian has higher fat, calories, and sulfur (S) content than other red durians, yellow and white durians. Red Horny Jameela durian has higher carbohydrate content than other red durians and white durians, but it is lower than yellow durians. Musang Merah durian contain the highest vitamin C and potassium (K) among other durians (red, yellow, and white). Pelangi durian has higher content of zink (Zn) and iron (Fe) than other red durians, white and yellow durians. Keywords: Nutrient compositions, Red durians, Banyuwang
Energy savings on automotive air conditioner using liquid-suction heat exchanger subcooler
No full textThe present study describes a numerical analysis of the effect of subcooling using liquid-suction heat exchanger (LSHX) on the performance of automotive air conditioner. Besides increasing the cooling capacity, subcooling using LSHX also generates superheating in the suction of the compressor, where the superheating ensures only vapor phase of refrigerant entering the compressor suction and reduces the risk of damage to the compressor. The results show that the refrigeration capacity improvements and COP improvements up to 11.86% and 5.64%, respectively, for the subcooling of 1 K to 10 K and the condenser temperature of 40°C to 50°C
A review on two-phase ejector as an expansion device in vapor compression refrigeration cycle
No full textThis paper presents a comprehensive review of two-phase ejector as an expansion device in vapor compression refrigeration cycle over the past two decades. It also covers research opportunities that are still open in the field of two-phase ejectors as an expansion valve. The studies of the application of ejector as an expansion device are relatively scarce compared to the application of ejector as heat-driven refrigeration system. A better understanding of two-phase flow in the ejector is necessary to optimize energy saving of the system. This paper also presents effects of geometric parameters of the ejector as an expansion valve on the performance of vapor compression refrigeration cycle. In addition, the effect of working fluid on the two-phase expansion refrigeration system is covered. The authors predict that the challenge of future research on design of two-phase ejector is how to generate a pressure rise in diffuser for minimum compressor work and optimum COP improvement
Numerical study of ejector as an expansion device in split-type air conditioner
No full textThis paper presents a numerical approach for determining the motive nozzle and constant-area of an ejector as an expansion device, based on cooling capacity of the split-type air conditioner using R22 as working fluid. The use of an ejector as an expansion device in split-type air conditioner can enhance the coefficient of performance (COP) system. Typically, the split-type air conditioner may be installed on the geographical area with moderate or high outdoor air temperature using capillary tube. For this reason, the motive nozzle and constant-area diameters of the ejector must be designed according to these conditions. The diameters of the ejector are crucial in improving the COP. The results showed that the motive nozzle diameter is constant (1.14 mm) with variations of the condenser temperature, whereas the constant-area diameter decreases as the condenser temperature increases
Effect of compressor discharge cooling using condensate on performance of residential air conditioning system
No full textStress corrosion cracking of steel and aluminum in sodium hydroxide: field failure and laboratory test
No full textThrough an investigation of the field failure analysis and laboratory experiment, a study on (stress corrosion cracking) SCC behavior of steel and aluminum was performed. All samples were extracted from known operating conditions from the field failures. Similar but accelerated laboratory test was subsequently conducted in such a way as to mimic the field failures. The crack depth and behavior of the SCC were then analyzed after the laboratory test and the mechanism of stress corrosion cracking was studied. The results show that for the same given stress relative to ultimate tensile strength, the susceptibility to SCC is greatly influenced by heat treatment. Furthermore, it was also concluded that when expressed relative to the (ultimate tensile strength) UTS, aluminum has similar level of SCC susceptibility to that of steel, although with respect to the same absolute value of applied stress, aluminum is more susceptible to SCC in sodium hydroxide environment than steel
Numerical investigation on ejector as an expansion device using R290 in residential air conditioner for various cooling capacity
No full textTypically, the residential air conditioner uses capillary tube as an expansion device. The friction between refrigerant flow and pipe wall, and also the changing of the velocity along capillary tube cause energy loss during expansion. The pressure drop from the condenser to the evaporator caused by capillary tube is considered isenthalpic process. An ejector as an expansion device can be used to recover energy loss during expansion process. Many researchers reported that the use of an ejector as an expansion device in vapor compression refrigeration cycle (VCRC) may lead to increase in the system performance. In this study, the numerical investigations were carried out on the residential air conditioners using the VCRC for various cooling capacity with R290 as working fluid. At present, the working fluid of R22 is widely used as refrigerant in residential air conditioners. Because R22 has a high global warming potential (GWP), as a result it must be phased out in the near future. Researchers recommended R290 (propane) as a substitute refrigerant for R22. As a natural refrigerant, R290 is abundant and relatively cheaper than that of R22. In addition, many studies reported that retrofit from R22 to R290 in air conditioner may result increase in coefficient of performance (COP). As a result, this study investigates the use of R290 for replacing R22 in residential air conditioner for various cooling capacity, viz. 2.5, 3.8 and 5.0 kW or the compressor capacity of 1, 1.5 and 2 HP. Three equations, i.e., conservation equations of mass, momentum and energy were applied to determine physical properties on each section of the ejector and the performances of the air conditioners. The main geometrics parameter of an ejector is area ratio (AR), which is defined as the ratio between the cross-sectional areas of mixing chamber and motive nozzle. The results showed that the diameter of motive nozzle is constant with the increase in ambient temperature, whereas the mixing chamber diameter slightly increases with the increase in ambient temperature. Meanwhile, the area ratio of ejector decreases with the increase in compressor capacity. In addition, the COP improvements of air conditioners are 4.94, 12.24 and 20.28% for ambient temperature of 30, 35 and 40 °C, respectively
A Study of Students' Attitudes towards the Use of Different Types of Audio- Visual Techniques for Biochemistry
No full textABSTRACT Lecture has been the most common form of teaching and learning process. Lectures delivered by using mixture of audio visual techniques are appreciated by students. The purpose of this study was to assess the student's preference regarding the use of different type's audio visual techniques for Biochemistry. Total 200 undergraduate medical students were participated in our questionnaire based study. Out of 200 students 115 (57.5%) are male and 85(42.5%) are female. In our study we found, 60 % of students preferred power point in combination with black board teaching and only 20% students' preferred power point presentation. The 15% of students favored the traditional black board teachings than projector or power point class. A very few (5 %) of students opted for the over head projector. In conclusion of our study we observed that the undergraduate medical students preferred a combination of power-point presentation along with blackboard teaching for biochemistry. It helps in both the visual and auditory senses to absorb information
Uji Komposisi 3 Media Tanam dengan 5 Varietas Tanaman Melon (Cucumis melo L.) dalam Penanaman Roof Farming
No full textUrbanisasi terus terjadi seiring berjalanya waktu dapat menimbulkan
masalah seperti alih fungsi lahan hingga permasalahan lingkungan, akan tetapi
juga merupakan tantangan dalam improvisasi teknik pertanain yang baru sehingga
pada tujuan akhirnya untuk memenuhi kebutuhan pangan yang tercukupi. Sistem
urban farming merupakan salah satu teknik pertanian yang dilakukan di daerah
perkotaan serta pertanian perkotaan memiliki manfaat ekologis yang
menguntungkan bagi lingkungan perkotaan. Melon (Cucumis melo L.) merupakan
bauh yang sudah dikenal pada masyarakat pada umumnya karena mengandung
gizi yang tinggi, akan tetapi secara fisiologis, tanaman melon senstif akan
perubahan lingkungan, dan rentan terhadap penyakit, sehingga pengelolaan
lingkungan mikro dan media tanam yang baik akan mempengaruhi pertumbuhan
dan hasil tanaman melon.
Tujuan dari penelitian ini yaitu untuk mengetahui potensi penggunaan roof
top dari pengaruh varietas tanaman melon dan komposisi media yang baik bagi
pertumbuhan dan hasil tanaman melon.
Penelitian dilakukan dari bulan Mei 2019 hingga Desember 2019, di roof
top gedung sentral Fakultas Pertanian, Universitas Brawijaya, Malang. Alat yang
digunakan pada penelitian ini yaitu, Polybag sebagi wadah media, jangka sorong
alat sebagai alat pengamatan, alat ukur (meteran), sekop, lux meter untuk
mengukur intensitas cahaya, botol semprot untuk penggunaan fungisida, pengukur
temperatur dan kelembaban, kamera digital sebagai alat dokumentasi, alat tulis,
yellow trap, ring sample untuk mengambil sampel dalam parameter sifat fisik
tanah, dan lanjaran bambu sebagai media perambatan tanaman melon. Bahan yang
digunakan yaitu 3 jenis media berupa tanah, bio kompos, dan sekam, serta 5
varietas tanaman melon, yaitu Melindo-15, Madesta, Glamour, Gracia, dan
Action, pupuk majemuk NPK (16:16:16), pupuk tunggal (KNO3), dan fungisida.
Penelitian ini menggunakan Rancangan Acak Kelompok Faktorial,
mempunyai 2 perlakuan yaitu 4 kombinasi perbandingan komposisi media antara
tanah, bio kompos, dan arang sekam yaitu 1:1:1, 2:1:1, 1:2:1, dan 1:1:2, dan 5
varietas melon. Terdapat 2 karakter pertumbuhan yang diamati yaitu panjang dan
jumlah daun, serta 7 karakter hasil yang diamati yaitu, waktu muncul bunga jantan
dan betina, luas permukaan daun, berat buah, diameter buah, dan jumlah buah per
tanaman. Untuk parameter pengamatan sifat fisik dan kimia media (tanah) yaitu,
Berat Isi (BI), kadar N, P, K, dan C-Organik, pF (0, 2.5, dan 4,2), dan KTK.
Observasi hama dan penyakit dilakukan pengukuran intensitas penyakit, dan jenis
hama dominan. Data dianalisis menggunakan dengan menggunakan analisis
ragam (ANNOVA) dengan taraf 5%, jika terdapat pengaruh berbeda nyata maka
akna dilakukan uji lanjut dengan menggunakan Duncan Multiple Range Test
(DMRT).
Hasil dari penelitian ditemukannya interaksi antara 5 varietas tanaman
melon dengan beberapa kombinasi campuran media tanam terhadap salah salah
iv
satu parameter pertumbuhan tanaman yaitu pada munculnya bunga jantan dan
betina, faktor ini kemungkinan pengaruh genetis yang lebih dominan dari pada
terhadap media tanam. Setiap varietas mempunyai karakter unggul dominan pada
setiap parameter pengamtan (Melindo pada bobot buah; Action pada jumlah daun,
jumlah buah, dan kemunculan bunga betina paling cepat; Glamour pada luas
daun; dan Madesta pada panjang tanaman). Komposisi media P1 (1:1:1)
menunjukan media yang dominan dengan value respon tertinggi terhadap
tanaman. Analisis kimia media tanaman menunjukan P3 (1:2:1) dengan nilai
analisis tertinggi secara keseluruhan (terkecuali kandungan kalium (K) tertinggi
pada media P2 (2:1:1)). Analisis fisik media tanam menunjukan setiap media
tanam mempunyai karakter unggul pada setiap parameter analisisnya (berat isi
oleh P2; pF 0 dan 2.5 oleh P3; pF 4.2 dan porositas oleh P4)
