Theoretical Exposition of A Single Electron Quantum Dot

This paper will review atomic-like phenomena in a semiconductor quantum dot which their size, shape and interactions can be precisely controlled through the use of nanofabrication technology. It has been shown that by confining electrons in three dimensions inside semiconductors, quantum dots can show many of the phenomena observed in atoms and nuclei and so called artificial atom. Because of its controlable system, it is possible to explore the correlation effects in regimes that cannot otherwise be accessed in other physical systems. For simplicity, this work will focus on a circular-shape single electron quantum dot trapped by polar two-dimensional harmonic potential in the presence of an external magnetic field. Both Zeeman splitting and spin orbit interaction are neglected in our calculation. The calculation show that Fock-Darwin spectrum will enter Landau regime, where when cyclotron frequency is much larger than potential confinement

Waktu Tumbuh Mata Tunas Daun Mangifera Indica L. Pada Berbagai Tingkatan

Fenology including one of scientific that study about development phases such as flowering character or development of leaf. One of leaf's development M.indica leaf has a very high diversity such as shape size even the color is often different according to its development as well as the buds that appear in the plan. The observation of buds's growth period in the M.indica plan has ever done before, but the levels and the time is still not clear. This research aimed to know the buds's time grows on various levels of M. indica so obtained the good appearance time and the level of M.indica species for further research material. The collecting data uses exploration method by exploring the area of sub-district Cibiru, district Bandung, West Java and an act of determine a level. The act of determine of the length and the diameter of each stand which is found at the three regions. The result of observation shows 7 of the 12 specimen that has been observed experiencing the growth of leaf buds. The average growth time of the buds in the specimen that experienced a growth is 13 days which dominate with pole, as for the existence of the variation of shape and bud color appearance enable to the existence of growth to the next phase from that buds

Seleksi Galur Lactobacillus Plantarum Untuk Inokulum Pada Pembuatan Silase

Eleven strains of Lactobacillus plantarum have been evaluated for their growth rate and ability to reduce pH during corn ensiling. Ensiling was carried out in small scale using plastic bag for 14 days. Soluble carbohydrate consumption, organic acids production and pH reduction were measured during fermentation. The growth rate of each strain was also determined in liquid medium. All of the 11 strains of L. plantarum tested were able to improve the ensiling process. However, strains T-16, T-25 and S-98 grew in liquid medium faster than the others, and were able to reduce pH of silage quicker than the other strains. The pH of silage inoculated with strain T-16, T-25 and S-98 decreased from about 5.60 to 4.23, 4.45 and 4.40, respectively, in two days, and to 3.98, 4.05 and 4.03, respectively, after 14 days fermentation. The acetic acid content of silages inoculated with those strains was low. Strains T-16 and T-25 were suitable as potential silage inoculants and their characteristics were comparable to the one isolated from a commercial silage inoculant

Improved ionic conductivity of lithium-zinc-tellurite glass-ceramic electrolytes

An enhancement in the secondary battery safety demands the optimum synthesis of glass-ceramics electrolytes with modified ionic conductivity. To achieve improved ionic conductivity and safer operation of the battery, we synthesized Li2O included zinc-tellurite glass-ceramics based electrolytes of chemical composition (85-x)TeO2·xLi2O·15ZnO, where x = 0, 5, 10, 15 mol%. Samples were prepared using the melt quenching method at 800 °C followed by thermal annealing at 320 °C for 3 h and characterized. The effects of varying temperature, alternating current (AC) frequency and Li2O concentration on the structure and ionic conductivity of such glass-ceramics were determined. The SEM images of the annealed glass-ceramic electrolytes displayed rough surface with a uniform distribution of nucleated crystal flakes with sizes less than 1 μm. X-ray diffraction analysis confirmed the well crystalline nature of achieved electrolytes. Incorporation of Li2O in the electrolytes was found to generate some new crystalline phases including hexagonal Li6(TeO6), monoclinic Zn2Te3O8 and monoclinic Li2Te2O5. The estimated crystallite size of the electrolyte was ranged from ≈40 to 80 nm. AC impedance measurement revealed that the variation in the temperatures, Li2O contents, and high AC frequencies have a significant influence on the ionic conductivity of the electrolytes. Furthermore, electrolyte doped with 15 mol% of Li2O exhibited the optimum performance with an ionic conductivity ≈2.4 × 10−7 S cm−1 at the frequency of 54 Hz and in the temperature range of 323–473 K. This enhancement in the conductivity was attributed to the sizable alteration in the ions vibration and ruptures of covalent bonds in the electrolytes network structures

Pengaruh Perendaman dan Perebusan terhadap Kandungan Protein, Gula, Total Fenolik dan Aktivitas Antioksidan Kerandang (Canavalia Virosa)

Kerandang (Canavalia virosa) tergolong tanaman legum dan menghasilkan biji, tumbuh menjalar di lahan pasir pantaiDaerah Istimewa Yogyakarta, khususnya di Kabupaten Bantul dan Kulon Progo dengan luas lahan sekitar 3.500 ha.Tanaman kerandang merupakan sumber protein nabati, mengandung senyawa fenolik dan memiliki aktivitas antioksidan.Penelitian tentang aktivitas antioksidan biji kerandang belum dilakukan. Penelitian ini bertujuan untuk mengetahuipengaruh perendaman dan perebusan terhadap Perubahan kandungan protein, gula, total fenolik dan aktivitas antioksidanbiji kerandang. Perendaman dilakukan pada 0, 12, dan 24 jam dengan rasio biji kerandang dan air sebesar 1:6 (b/v).Perlakuan perendaman ini dikombinasikan dengan perebusan biji pada suhu didih air (80 – 90 ºC) selama 0, 10, dan20 menit. Perbandingan biji kerandang dan air untuk perebusan adalah 1:5 (b/v). Pengujian yang dilakukan meliputikadar protein, jenis gula, total fenolik dan aktivitas antioksidan. Penelitian dilakukan menggunakan Rancangan AcakLengkap dengan ulangan dua kali. Hasil penelitian menunjukkan bahwa kadar protein biji kerandang menurun denganperlakuan perendaman dan perebusan. Biji kerandang mengandung oligosakarida tahan cerna (raÞ nosa) yang cukuptinggi. Kandungan total fenolik biji kerandang segar sebesar 7,42 g GAE/100 g biji kerandang. Perlakuan perendamandan perebusan menyebabkan kandungan total fenolik menurun sampai dengan 74,93 %. Aktivitas antioksidan bijikerandang dinyatakan sebagai Radical Scavenging Activity sebesar 10,22 %. Pada perendaman selama 12 dan 24 jamterjadi penurunan aktivitas antioksidan

Pembinaan Budidaya Pertanian Berbasis Smart Vertical Farming untuk Pemanfaatan Lahan Sempit di Daerah Perumahan

Pembangunan Perumahan di perkotaan yang sangat pesat, cenderung tidak mempertimbangkan faktor konservasi lingkungan dengan memberikan sumbangsih ruang terbuka hijau yang terbatas. Pekarangan merupakan lahan yang potensial untuk dikembangkan menjadi lahan pertanian produktif terutama untuk pemenuhan kebutuhan pangan yang bergizi bagi si pemilik. Keterbatasan lahan bukanlah hal yang menjadi hambatan untuk mengaktualisasi potensi nilai ekonomi. Lahan di lingkungan Perumahan yang cenderung terbatas dapat dioptimalkan untuk ditanami tanaman yang memiliki nilai ekonomi tinggi seperti tanaman pangan, tanaman hias, tanaman obat dan tanaman penyuplai oksigen dalam jumlah besar. Salah satu model optimalisasi lahan terbatas untuk mendukung pertanian sederhana di lingkungan Perumahan yaitu model smart vertical farming. Metode pelaksanaan kegiatan antara lain dengan memberikan pelatihan teknik vertical farming, praktik budidaya vertical farming, pembuatan model smart vertical farming dan cara melakukan perawatan. Paparan pelatihan dan praktik disampaikan oleh narasumber dari bidang agribisnis, sedangkan pemodelan smart vertical farming disampaikan oleh narasumber dari bidang teknik informatika. Opini yang berkembang di masyarakat bahwa menerapkan konsep vertical farming adalah sesuatu yang mahal dan rumit, nyatanya tidak semuanya benar. Dengan bermodalkan bibit tanaman, paralon atau botol bekas, maka masyarakat dapat membuat model pertanian vertikal. Model tersebut akan menjadi lebih efisien apabila menerapkan konsep pertanian cerdas berbasis sensor dalam pemantauan dan pengelolaan tanaman. Hasil dari kegiatan baik pelatihan, praktik, maupun pembuatan model smart vertical farming sangat diterima dengan baik oleh masyarakat