1,400 research outputs found

    High-pressure synthesis and structural behavior of sodium orthonitrate Na3NO4

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    Sodium orthonitrate (Na3NO4) is an unusual phase containing the first example of isolated tetrahedrally bonded NO43- groups. This compound was obtained originally by heating together mixtures of Na2O and NaNO3 for periods extending up to > 14 days in evacuated chambers. Considering the negative volume change between reactants and products, it was inferred that a high-pressure synthesis route might favor the formation of the Na3NO4 compound. We found that the recovered sample is likely to be a high-pressure polymorph, containing NO43- groups as evidenced by Raman spectroscopy. The high-pressure behavior of Na3NO4 was studied using Raman spectroscopy and synchrotron X-ray diffraction in a diamond anvil cell above 60 GPa. We found no evidence for major structural transformations, even following laser heating experiments carried out at high pressure, although broadening of the Raman peaks could indicate the onset of disordering at higher pressure

    Redesain Rusunawa Mahasiswa pada Universitas Muhammadiyah Ponorogo dengan Pendekatan Kenyamanan Termal

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    Rusunawa Mahasiswa Universitas Muhammadiyah Ponorogo merupakan universitas berbasis agama Islam yang memiliki berbagai macam perminatan jurusan. Sebagai universitas yang terfavorit, universitas dituntut untuk menyediakan fasilitas hunian berupa rusunawa. Rusunawa dituntut untuk mempunyai tingkat Kenyamanan yang tinggi ditinjau dari fungsinya sebagai tempat hunian. Permasalahan utama pada rusunawa yaitu orientasi bangunan dan bukaan menghadap ke Timur dan Barat yang berdampak pada Kenyamanan termal yang dirasakan oleh penghuninya. Penelitian dilakukan untuk mengetahui tingkat Kenyamanan termal penghuni rusunawa serta untuk mengetahui rekomendasi desain bangunan yang dapat meningkatkan Kenyamanan termal penghuninya. Metode pengumpulan data penelitian ini dengan pengukuran langsung temperatur, kelembaban, dan kecepatan udara pada sampel kamar yang terpilih. Pembagian kuesioner dilakukan untuk mengetahui sensasi termal, tingkat kepuasan, aktivitas, pakaian yang digunakan, dan perlakuan terhadap buka tutup jendela serta pembayangan internal. Hasil penelitian menunjukkan kondisi Kenyamanan termal mahasiswa belum tercapai. Rekomendasi desain yang diberikan yaitu memperluas bukaan 3m2 serta ventilasi 1,3 m2. Kemudian mengganti pembayang eksternal dengan sudut 45⁰ sepanjang 0,9 m. Rekomendasi desain bangunan dibandingkan dengan kondisi bangunan eksisting melalui simulasi digital, hasil rekomendasi dapat menurunkan temperatur udara 0,02⁰C hingga 0,8⁰C. Rekomendasi pada area luar bangunan berupa penambahan area penghijauan serta penggantian paving menjadi grass block

    Identifikasi Kematangan Buah Tomat Berdasarkan Warna Menggunakan Metode Jaringan Syaraf Tiruan (Jst)

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    Proses pemilihan produk hasil pertanian dan perkebunan umumnya sangat bergantung pada presepsi manusia terhadap komposisi warna yang dimiliki citra yaitu buah­buahan. Cara manual dilakukan berdasarkan pengamatan visual secara langsung pada buah yang akan diklasifikasi. Identifikasi dengan cara ini memiliki beberapa kelemahan diantaranya adalah waktu yang dibutuhkan relatif lama serta menghasilkan produk yang beragam karena adanya keterbatasan visual manusia, tingkat kelelahan dan perbedaan persepsi tentang mutu buah. Perkembangan ilmu pengetahuan dan teknologi pengolahan citra digital memungkinkan untuk memilah produk pertanian dan perkebunan tersebut secara otomatis dengan bantuan aplikasi pengolahan citra. Identifikasi kematangan buah tomat ini menerapkan metode pembelajaran Perceptron.  Pendukung identifikasi menggunakan bantuan  media  webcam  sebagai  pengambilan  gambar  tomat  yang  dibuat  histogram  warnanya  kemudian diidentifikasi menggunakan jaringan syaraf tiruan agar komputer dapat memperoleh informasi citra dan dapat mengetahui jenis kematangan buah tersebut. Tingkat keberhasilan identifikasi kematangan buah tomat yang didapatkan menggunakan  metode pembelajaran perceptron dengan  tingkat  keberhasilan 43,33%. Dari hasil identifikasi yang diperoleh menghasilkan 3 output yaitu Mentah 10%, Setengah Matang  6,66%, dan Matang 26,66%

    Analisis Perbandingan Pendapatan Nelayan Jaring Pejer (Bottom Set Gill Net) Anggota Kub (Kelompok USAha Bersama) Dan Non Anggota Kub Di Desa Sukoharjo Kecamatan Rembang Kabupaten Rembang

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    Mayoritas masyarakat Desa Sukoharjo bermatapencaharian sebagai nelayan penangkap rajungan. Jaring Pejer (bottom set gill net) adalah alat tangkap yang banyak digunakan oleh nelayan Sukoharjo untuk menangkap rajungan. Tujuan penelitian ini adalah menganalisis produksi hasil tangkapan rajungan dan pengaruhnya terhadap pendapatan nelayan jaring Pejer dan menganalisis perbedaan pendapatan nelayan anggota KUB dan non anggota KUB dalam satu tahun. Populasi dalam penelitian ini adalah nelayan jaring Pejer di Desa Sukoharjo yang merupakan anggota KUB dan non-anggota KUB. Metode penelitian yaitu metode deskriptif studi kasus, dengan metode pengambilan sampel purposive sampling. Hasil penelitian menunjukkan bahwa Pendapatan bersih yang diperoleh nelayan jaring Pejer anggota KUB adalah sebesar Rp 36.237.500,-/tahun atau Rp 3.675.000,-/bulan, sedangkan nelayan jaring Pejer non anggota KUB sebesar Rp 27.695.267,-/tahun atau Rp 3.258.267,-/bulan. Jumlah trip penangkapan dalam satu bulan adalah 20 trip dan dalam satu tahun terdapat 8,5 bulan operasi penangkapan. Rata-rata produksi rajungan dalam satu tahun sebanyak 675 kg. Berdasarkan hasil regresi linear sederhana yaitu nilai korelasi 0,775, produksi rajungan memiliki keeratan hubungan yang kuat pada pendapatan bersih yang diterima nelayan jaring Pejer, karena semakin besar jumlah produksi rajungan maka semakin tinggi tingkat pendapatannya. Berdasarkan hasil analisis Uji T, nilai Sig 2-tailed (0,002) < α = 5% (0,05) maka H1 diterima artinya pendapatan bersih nelayan anggota KUB lebih besar daripada nelayan non anggota KUB dalam satu tahun ini. Dana BLM dari pemerintah hanya diberikan satu kali saja, sehingga dana bantuan tersebut tidak memiliki pengaruh yang cukup besar dan berkelanjutan terhadap pendapatan nelayan jaring Pejer di Desa Sukoharjo. The majority of Sukoharjo villagers as a fishermen blue swimming crabs catcher. Pejer nets (bottom set gill net) is the gear used by fishermen to catch blue swimming crabs in Sukoharjo. The purposes of this research are analyzing the production of blue swimming crabs and its effect with fishermen's income and analyzing the differences income of fishermen KUB's member and non KUB's member within a year. The population of this research is the Pejer's fishermen in Sukoharjo village Pejer which is member of KUB and non-members of KUB. Research method is descriptive case study, sampling method is used purposive sampling. The results showed that the members of KUB fishing income is Rp 36.237.500,-/year or Rp 3.675.000,-/month and non-members of KUB fishing income is Rp 27.695.267,-/year or Rp 3.258.267,-/month. Trips catching total in a month is 20 trip and within a year there are 8,5 months of fishing operated. Production of blue swimming crabs in the village of Sukoharjo average in one year is 675 kg. Based on the results of a simple linear regression correlation value 0,775, the production of blue swimming crab has a strong correlation with the Pejer's fishermen income, because the greater production of blue swimming crab, then the level of fishermen's income are upper. Based on the analysis of T-Test, Sig 2-tailed (0,002) < α = 5% (0,05) then H1 accepted so there are differences of net income per year between fishermen of KUB's member and non KUB's member. BLM funds from the government are only given one time, so that these funds do not have an appreciable impact on revenues and sustainable of fishermen Pejer net in the Sukoharjo Village

    The Use of Graphitic Carbon Nitride Based Composite Anodes for Lithium-Ion Battery Applications

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    Graphitic carbon nitride (gCN) is shown to undergo lithium insertion reactions applicable with lithium-ion battery anodes. Lithium capacity was found to be substantially lower than theoretically expected, so the properties of gCN composited with conducting graphite (CG), which was added to improve the performance, were investigated. The electrodes exhibited a systematic increase in lithium uptake with CG content, but the capacity never exceeded that of graphite. It is shown that electron transport via conducting pathways was limiting. Li+ uptake for 10 % gCN was similar to a graphite electrode, indicating that gCN does play a role in determining the storage capacity

    Dihydrogen: Vs. hydrogen bonding in the solvation of ammonia borane by tetrahydrofuran and liquid ammonia

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    The solvation structures of two systems rich in hydrogen and dihydrogen bonding interactions have been studied in detail experimentally through neutron diffraction with hydrogen/deuterium isotopic substitution. The results were analysed by an atomistic Monte Carlo simulation employing refinement to the experimental scattering data. The systems studied were the hydrogen storage material ammonia borane (NH 3 BH 3 , AB) dissolved in tetrahydrofuran (THF), and liquid ammonia (NH 3 ), the latter in which AB shows unusually high solubility (260 g AB per 100 g NH 3 ) and potential regeneration properties. The full orientational and positional manner in which AB-AB, AB-THF and AB-NH 3 pairs interact with each other were successfully deciphered from the wide Q-range total neutro n scattering data. This provided an unprecedented level of detail into such highly (di)hydrogen bonding solute-solvent interactions. In particular this allowed insight into the way in which H-B acts as a hydrogen bond acceptor. The (di)hydrogen bonding was naturally determined to dictate the intermolecular interactions, at times negating the otherwise expected tendency for polar molecules to align themselves with anti-parallel dipole moments. Several causes for the extreme solubility of AB in ammonia were determined, including the ability of ammonia to (di)hydrogen bond to both ends of the AB molecule and the small size of the ammonia molecule relative to AB and THF. The AB B-H to ammonia H dihydrogen bond was found to dominate the intermolecular interactions, occurring almost three times more often than any other hydrogen or dihydrogen bond in the system. The favourability of this interaction was seen on the bulk scale by a large decrease in AB clustering in ammonia compared to in the dihydrogen bond-less THF

    Formas de uréia e doses de nitrogênio em cobertura na qualidade fisiológica de sementes de trigo.

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    A adubação nitrogenada, além de aumentar a produtividade, pode favorecer a qualidade fisiológica das sementes. O trigo no Paraná é geralmente cultivado após a cultura da soja, com isso a palha da soja e outros fatores do solo podem minimizar o efeito do nitrogênio no trigo. O objetivo do trabalho foi avaliar o efeito de doses de adubação nitrogenada em cobertura e de diferentes formas de ureia, na qualidade fisiológica de sementes de genótipos de trigo. Os experimentos foram conduzidos em Londrina e Ponta Grossa-PR. As áreas experimentais são manejadas no sistema de plantio direto com rotação de culturas, sendo a soja a cultura anterior. Foram avaliadas sementes de três genótipos de trigo (BRS 208, BRS Pardela e IWT 04008) cultivados sob quatro doses de nitrogênio em cobertura (0, 40, 80 e 120 kg ha-1), provenientes de três formas de ureia (convencional, com inibidor de urease e protegida). A adubação nitrogenada de cobertura foi realizada durante o estádio de perfilhamento, aos 20 dias após a emergência. Avaliou-se o teor de nitrogênio nas sementes, a massa de 1000 sementes, a germinação e o vigor (primeira contagem, frio, emergência, massa seca de plântulas, envelhecimento acelerado e condutividade elétrica). Os genótipos de trigo foram analisados conjuntamente para cada local. A linhagem IWT 04008 e a cultivar BRS Pardela apresentam sementes com qualidade fisiológica superior a cultivar BRS 208. Somente em Londrina, em consequência do acamamento, as doses de nitrogênio influenciaram negativamente a massa de 1000 grãos e a condutividade elétrica e, positivamente o teor de proteína. As formas de ureia e as doses de nitrogênio não alteram a qualidade fisiológica das sementes de diferentes genótipos de trigo

    Scorah's quickfit

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    Couette’s Cell

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