Pengaruh Waktu Aplikasi Dan Pemberian Berbagai Dosis Kompos Azolla (Azolla Pinnata) Terhadap Pertumbuhan Dan Produksi Tanaman Pakchoy (Brassica Rapa Var. Chinensis)

Peningkatan dalam tanaman produksi tanaman pakchoy dapat dilakukan dengan pemupukan. Pemupukan dapat berupa pupuk organik maupun pupuk anorganik. Pupuk organik yang memiliki nilai kandungan N tinggi yaitu kompos Azolla. Penelitian bertujuan untuk mendapatkan waktu aplikasi serta mendapatkan dosis kompos azolla yang tepat dalam peningkatan produksi tanaman pakchoy (Brassica rapa var. chinensis). Penelitian dilaksanakan pada bulan September – Oktober 2014 di Desa Pandanrejo Kecamatan Bumiaji, Batu. Rancangan yang digunakan dalam penelitian ini adalah Rancangan Acak Kelompok (RAK) Faktorial dengan 2 faktor yang diulang dengan 3 kali. Faktor 1 waktu aplikasi (A), yang terdiri dari : A1 = 0 hari (saat tanam), A2 = 7 hari sebelum tanaman, A3 = 14 hari sebelum tanaman. Faktor 2 dosis kompos Azolla (B) yang terdiri dari : B1 = 3 ton ha⁻¹, B2 = 6 ton ha⁻¹, B3 = 9 ton ha⁻¹. Hasil penelitian menunjukkan tidak terjadi interaksi waktu aplikasi dan dosis kompos Azolla terhadap semua variabel pengamatan. Perlakuan waktu aplikasi kompos azolla 7 hari sebelum tanam mempunyai tinggi tanaman dan jumlah daun yang lebih tinggi dibandingkan perlakuan waktu aplikasi 14 hari sebelum tanam. Perlakuan dosis kompos Azolla berpengaruh nyata terhadap tinggi tanaman dan jumlah daun pada umur 28 hst. Perlakuan dosis kompos Azolla 6 ton ha⁻¹ mempunyai tinggi tanaman yang lebih tinggi dibandingkan dosis kompos Azolla 3 dan 9 ton ha⁻¹, tetapi mempunyai jumlah daun yang tidak berbeda nyata dengan 9 ton ha⁻¹

Pengaruh Dosis Pupuk Nitrogen Dan Tingkat Kepadatan Tanaman Terhadap Pertumbuhan Dan Hasil Tanaman Kailan (Brassica Oleraceae L.)

Peningkatan produksi kailan dapat dilaku-kan dengan pengaturan tingkat kepadatan tanaman dan pupuk nitrogen. Pada tingkat kepadatan optimal, kompetisi antar tanam-an masih terjadi sehingga pertumbuhan dan hasil per individu menjadi berkurang, namun karena jumlah tanaman per hektar ber-tambah dengan meningkatnya populasi, maka hasil panen per hektar masih dapat meningkat. Suplai nitrogen akan membuat bagian tanaman menjadi hijau karena me-ngandung klorofil yang berperan dalam fo-tosintesis. Unsur tersebut juga bermanfaat untuk mempercepat pertumbuhan tinggi ba-gi tanaman, memperbanyak jumlah anak-an, mempengaruhi lebar dan panjang daun serta membuat menjadi besar, menambah kadar protein dan lemak bagi tanaman. Pe-nelitian dilaksanakan pada bulan April sam-pai Juli 2014 di Cangar Kecamatan Bumiaji Kota Batu Malang. Bahan yang digunakan adalah benih kailan varietas Taichung, pu-puk urea, SP-36, KCl, pupuk kandang, kom-pos, dan air. Alat yang digunakan adalah cangkul, gembor, cetok, tugal, tray pot, sprayer, label, penggaris, alat tulis, jangka sorong, kamera, dan timbangan. Penelitian menggunakan RAK faktorial terdiri dari per-lakuan pertama P1: Kepadatan 25 tanaman per petak (1m2), P2: Kepadatan 30 tanaman per petak (1m2). Perlakuan kedua N1: 80,5 kg N ha-1, N2: 92 kg N ha-1, N3: 103,5 kg N ha-1, N4: 115 kg N ha-1, N5: 126,5 kg N ha-1. Dari hasil penelitian diketahui bahwa tidak terjadi interaksi nyata antara kedua perlaku-an tersebut terhadap pertumbuhan dan ha-sil tanaman kailan. Pada tingkat kepadatan tanaman 30 tanaman per 1m2 dan perlaku-an dosis pupuk nitrogen 126,5 kg N ha-1 me-nunjukkan hasil tertinggi pada semua kom-ponen hasil kecuali indeks panen disban-dingkan dengan perlakuan lainnya

Electrical treeing and partial discharge characteristics of silicone rubber filled with nitride and oxide based nanofillers

This article presents a study on electrical treeing performances with its associated partial discharge (PD) and the influence of filler concentration in silicone rubber (SiR) samples which are filled with silicon dioxide (SiO2) and silicon nitride (Si3N4) as nanofillers for electrical tree growth suppression. There are many researches on electrical treeing in SiR with SiO2 nanofillers but none of the publication have reported on Si3N4 nanofillers for suppression of the electrical tree growth. In this study, the treeing experiments were conducted by applying a fixed AC voltage of 10 kV and 12 kV at power frequency of 50 Hz on unfilled SiR, SiR/SiO2, and SiR/Si3N4 nanocomposites with different filler concentrations by 1, 3, and 5 weight percentage (wt%) and the electrical treeing parameters were observed with its correlated PD patterns. The outcome from this study found that the SiR/Si3N4 nanocomposites were able to withstand the electrical treeing better than the pure SiR or SiR/SiO2 nanocomposites. Furthermore, the increase in filler concentration improved the electrical tree performances of the nanocomposites. This finding suggests the Si3N4 can be used as filler in polymeric insulating materials for electrical tree inhibition. Meanwhile, the PD activity shows increment when the tree progresses thereby indicating correlation in both parameters which can be as key parameter for monitoring unseen electrical treeing in the opaque samples

Synthesis and characterization of ETS-10/Chitosan nanocomposite membranes for pervaporation

Chitosan (CS) and microporous titanosilicate ETS-10/CS mixed matrix membranes (MMMs) were prepared. The pervaporation performance was tested on the of waterethanol mixtures in the range 85-96 wt. % ethanol. The permeate flux increased from 0.45 to 0.55 kg m-2 h-1 at 50 ºC for the ETS-10/CS MMM with respect to the pure CS membranes. Characterization by SEM and TEM, XRD, DSC and TGA allowed inferring an intimate contact between the dispersed ETS-10 and the continuous chitosan phase. The 5 wt. % loading of titanosilicate scarcely decreased the hydrophilic character of the mixed matrix membrane but increased the molecular sieving effect on the transport and separation properties, thus affecting the membrane behavior on pervaporation.The authors gratefully acknowledge the Spanish Ministry of Economy and Competitiveness (MINECO) for financial support through projects MAT2010-15870, at the Universidad de Zaragoza, and CTQ2012-31229 and “Ramón y Cajal” programme RYC-2011-08550, at the Universidad de Cantabria. Financial support from the Regional Government of Aragón (DGA) and the European Social Fund (ESF) is also gratefully acknowledged

Fractal analysis of electrical tree grown in silicone rubber nanocomposites

Electrical treeing is one of the main reasons for long-term degradation of high voltage insulation especially in the cable accessory which commonly made from silicone rubber due to non-uniformly structures of the cable accessories. Recently, the combination of nanofillers with the silicone rubber matrix can reduce the possibility of the electrical treeing to grow further by changing its patterns and slow-down its propagation. However, the influences of nanofillers on the tree hindrance and its patterns are not well understood. This paper explores the influence of nanofiller on tree pattern in silicon rubber. The electrical tree patterns were characterized using fractal analysis. The box-counting method was used to measure the fractal dimension and lacunarity to obtain the structure of the tree pattern during the electrical tree growth. The structure of the electrical tree in silicone rubber nanocomposites has higher fractal dimension and lacunarity. Sample with nanofiller possesses dominant fractal dimension of tree growth compared to the sample without nanofiller

Partial Discharge and Breakdown Strength of Plasma Treated Nanosilica/LDPE Nanocomposites

Nanocomposites have been actively studied in recent years as an insulating material due to their excellent in electrical, mechanical and thermal properties. Even though, the addition of nanoparticles into polymer matrices showed better performance in relation to partial discharge (PD) and AC breakdown strength tests. However, the introduction of nanoparticles could lead to the formation of agglomeration of the fillers which may nullify the true capabilities of the composites. Therefore, silane coupling agent was introduced for surface functionalization treatment of the nano filler but among the issues associated are toxicity and complexity. In the present study, atmospheric pressure plasma is proposed to enhance the surface functionalization of the nano filler. This proposed method was used to treat the nanosilica (SiO 2 ) surfaces to enhance the interfacial interaction between the host (LDPE) and nano filler. SiO 2 nano filler was added into the LDPE at weight percentages of 1, 3 and 5%. The phase-resolved PD behaviour and Weibull analysis of AC breakdown strength of untreated and plasma-treated LDPE nanocomposites were measured to evaluate the performance of the samples. As results, the plasma treated LDPE nanocomposites experience apparent increments of the PD resistance and AC breakdown strength as compared to the untreated nanocomposites. It is implied that the plasma treatment of nanosilica has contributed to the enhancement of the filler dispersion and eventually reducing the agglomeration

Clarification of the optimum silica nanofiller amount for electrical treeing resistance

This paper aims to clarify the optimum amount of fumed silica (SiO2) nanofiller in resisting the initiation and propagation of electrical treeing in silicone rubber (SiR). Unlike other works, SiR/SiO2 nanocomposites containing seven different weight percentages of SiO2 nanofiller were prepared for this purpose. To achieve the objective, the electrical tree characteristics of the SiR/SiO2 nanocomposites were investigated by comparing the tree initiation voltage, tree breakdown time, tree propagation length and tree growth rate with its equivalent unfilled SiR. Moreover, the structural and morphological analyses were conducted on the SiR/SiO2 nanocomposite samples. The results showed that the SiR, when added with an appropriate amount of SiO2 nanofiller, could result in an improved electrical tree resistance. It implies that the 5 wt% of silica is the optimum amount to achieve the optimal electrical tree resistance such that above 5 wt%, the tree resistance performance has been abruptly reduced, subjected to the agglomeration issue