scholarly journals Analisis Komposisi Serbuk Arang Karamunting (Melastoma Malabathricum) Dengan Serbuk Arang Sirih Hutan (Piper Aduncum) Terhadap Kualitas Briket Arang

2021 ◽  
Vol 1 (3) ◽  
pp. 287-300
Author(s):  
Rindayatno Rindayatno ◽  
Akbar Fikri ◽  
Agus Nur Fahmi
Keyword(s):  
Melastoma Malabathricum ◽  
C 50 ◽  
Piper Aduncum

Pertambahan penduduk yang semakin meningkat menimbulkan kekhawatiran akan terjadi kelangkaan bahan bakar akibat peningkatan kebutuhan bahan bakar di masa yang akan datang. Biomassa berpotensi menjadi sumber energi alternatif ditengah terbatasnya cadangan energi fosil. Briket arang adalah salah satu sumber energi alternatif berbasis biomassa (tumbuhan) yang dapat mendukung pemenuhan kebutuhan energi, membuka lapangan kerja serta emisi yang relatif ramah lingkungan. Penelitian ini bertujuan untuk mencari kombinasi komposisi terbaik campuran arang Karamunting (Melastoma malabathricum) dan Sirih Hutan (Piper aduncum) terhadap kualitas briket arang. Proses pengarangan menggunakan tungku pengarangan dengan metode tidak langsung. Pola penelitian yang digunakan adalah rancangan acak lengkap (RAL) dengan 5 perlakuan yaitu (A) komposisi 100% Karamunting dan 0% Sirih Hutan, (B) 75% Karamunting dan 25% Sirih Hutan, (C) 50% Karamunting dan 50% Sirih Hutan, (D) 25% Karamunting dan 75% Sirih Hutan, serta (E) 0% Karamunting dan 100% Sirih Hutan. Perlakuan terbaik terhadap kualitas briket arang perlakuan A (100% karamunting) dengan nilai kerapatan 0,666 g/cm3, kadar air 3,697%, keteguhan tekan 15,079 kg/cm2, kadar zat mudah menguap 16,70%, kadar abu 7,30%, kadar karbon terikat 76,00% dan kalor 6.807,33 kal/g. Briket arangdengan campuran serbuk arang karamunting 75% dan sirih hutan 25% adalah komposisi campuran terbaik dengan sifat kualitas briket arang; kerapatan 0,664 g/cm3, kadar air 4,521%, uji tekan 14,559kg/cm2, kadar zat mudah menguap 18,3,7%, kadar abu 7,80%, karbon terikat 72,90%, dan nilai kalor 6.556,66 kal/g.

On the Preparation of Bovine α-Thrombin

1978 ◽  
Vol 39 (01) ◽  
pp. 193-200 ◽  
Author(s):  
Erwin F Workman ◽  
Roger L Lundblad
Keyword(s):  
Immobilized Enzyme ◽  
Catalytic Properties ◽  
Specific Activity ◽  
Guanidine Hydrochloride ◽  
Low Molecular Weight ◽  
Reversible Process ◽  
Gel Beads ◽  
Tissue Thromboplastin ◽  
C 50 ◽  
Hydrolysis Of

SummaryAn improved method for the preparation of bovine α-thrombin is described. The procedure involves the activation of partially purified prothrombin with tissue thromboplastin followed by chromatography on Sulfopropyl-Sephadex C-50. The purified enzyme is homogeneous on polyacrylamide discontinuous gel electrophoresis and has a specific activity toward fibrinogen of 2,200–2,700 N.I.H. U/mg. Its stability on storage in liquid media is dependent on both ionic strenght and temperature. Increasing ionic strength and decreasing temperature result in optimal stability. The denaturation of α-thrombin by guanidine hydrochloride was found to be a partially reversible process with the renatured species possessing properties similar to “aged” thrombin. In addition, the catalytic properties of a-thrombin covalently attached to agarose gel beads were also examined. The activity of the immobilized enzyme toward fibrinogen was affected to a much greater extent than was the hydrolysis of low molecular weight, synthetic substrates.

Plasminogen-Activator in Human Early Milk: Its Partial Purification and Characterization

1981 ◽  
Vol 45 (02) ◽  
pp. 121-126 ◽  
Author(s):  
Utako Okamoto ◽  
Noboru Horie ◽  
Yoko Nagamatsu ◽  
Jun-Ichiro Yamamoto
Keyword(s):  
Plasminogen Activator ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Partial Purification ◽  
Order Kinetic ◽  
Diisopropyl Fluorophosphate ◽  
Step Procedure ◽  
Activity Band ◽  
C 50 ◽  
Gel Isoelectric Focusing

SummaryMilk plasminogen-activator was partially purified from human transitional milk collected at about 10 days after delivery, by a five-step procedure involving chloroform treatment, ammonium sulfate precipitation, and column chromatography on Sephadex G-150, CM Sephadex C-50 and DEAE Sephadex A-50. This gave milk-activator with a maximum purification factor of about 2,400-fold with respect to the skimmed milk. The CM Sephadex-step preparation showed, on polyacrylamide gel electrophoresis, a single plasminogen-activator activity band located between the bands of albumin and prealbumin of human serum. This preparation exhibited no kinin forming activity. The activator hydrolyzed acetyl-glycyl-L-lysine methyl ester with similar order kinetic constants to urokinase, and was inhibited strongly by diisopropyl-fluorophosphate. The molecular weight of the activator as estimated by gel filtration was approximately 86,000, the isoelectric points as estimated by gel isoelectric focusing were pH 7.2, 6.9 and 6.6, and the activator activity was not quenched by antiurokinase globulin, indicating that the milk-activator is a different entity from urokinase.

Penerapan Teknologi Seed Bank Sebagai Upaya Rehabilitasi Kawasan Ekosistem Leuser Pasca Kerusakan Akibat Pembukaan Perkebunan Kelapa Sawit

2019 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Sri Jayanthi, Zulfan Arico
Keyword(s):  
Seed Bank ◽  
Melastoma Malabathricum ◽  
Cocculus Hirsutus

Penelitian ini bertujuan untuk mengkaji keanekaragaman jenis tumbuhan penyusun vegatasi kawasan ekosistem Taman Nasional Gunung Leuser yang mengalami kerusakan akibat pembukaan perkebunan kelapa sawit dengan menggunakan teknologi seed bank. Waktu penelitian berlangsung mulai bulan April sampai September 2018. Pengambilan sampel tanah menggunakan metode jalur. Pada jalur pengamatan diambil cuplikan sampel tanah sesuai dengan kondisi tutupan tajuk dan kerapatan vegetasi yang dibagi menjadi 3 titik yaitu jarang, sedang dan rapat. Kemudian masing-masing titik diambil sampel tanah secara random  sebanyak 3 kali ulangan dengan menggunakan kotak besi berukuran 25 x 25 cm sedalam: (i) 0-5 cm, (ii) 5-10 cm, (iii) 10-15 cm. Tanah kemudian dimasukkan kedalam kantong plastik dengan menggunakan cangkul kemudian diberi label.ampel tanah kemudian disimpan di dalam rumah kaca untuk selanjutnya dilakukan uji perkecambahan. Informasi tentang cadangan biji di dalam tanah penting dalam studi ekologi komunitas karena dapat menggambarkan vegetasi yang ada di atasnya dan mengetahui potensi jenis tanaman lain yang akan tumbuh di habitat tersebut. Dari hasil penelitian ditemukan 13 famili dengan 18 jenis yang tumbuh pada bak-bak penelitian yang terdiri dari 7 jenis pohon dan 11 jenis golongan tumbuhan bawah dengan jumlah seluruhnya adalah 366 spesies. Dari hasil kekayaan jenis kecambah yang tumbuh pada bak pengamatan didapatkan nilai KR, FR dan INP tertinggi terdapat pada jenis Melastoma malabathricum dengan nilai KR (63,115 %), nilai FR (32,692 %) dan INP (95,807 %). Sedangkan untuk nilai terendah terdapat pada jenis Cocculus hirsutus dengan nilai KR (0,273 %), FR (0,962 %) dan INP (1,235 %). Jenis dan jumlah kecambah sangat dipengaruhi oleh ketinggian tempat dan tidak dipengaruhi oleh kedalaman tanah. Jumlah biji terbanyak yang ditemukan di lantai hutan adalah jenis Macaranga gigantea yaitu 28 biji dan jumlah biji terendah yang ditemukan adalah jenis Villebrunea rubescens, yaitu sebanyak 7 biji.

Avaliação e otimização das condições de obtenção do ácido acetilsalicílico para fins didáticos

2019 ◽  
Vol 30 (2) ◽  
pp. 54
Author(s):  
Leslie Tauany Schneider da Luz ◽  
Sandra Inês Adams Angnes Gomes ◽  
Marilei Casturina Mendes Sandri ◽  
Flávia De Mello ◽  
Juliana Aparecida Bolzan
Keyword(s):  
C 50

A síntese do ácido acetilsalicílico (AAS) é muito empregada em aulas experimentais de Química para explorar o ensino de reações nucleofílicas e o processo de purificação por recristalização. Considerando a diversidade de protocolos disponíveis na literatura, com divergências nas condições experimentais, este trabalho teve como objetivo otimizar as condições de tempo e temperatura da síntese do AAS e, concomitante, melhorar a verdura química do processo visando maior eficiência mássica e energética, de acordo com os princípios 1, 2 e 6 da Química Verde (QV). Para isso, propôs-se a síntese de AAS a temperaturas de 40 °C, 50 °C, 60 °C, 70 °C, 80 e 90 °C durante 10, 20, 30 e 40 minutos de reação. Os resultados apontam que o AAS obtido em 20 minutos a 80°C apresentou os melhores resultados: um bom rendimento, 77,70 ± 0,01 %, com ponto de fusão 133 °C-134 °C, com Eficiência de Massa 24 % e Fator E 3,10; as melhores métricas de energia, <em>Throughput</em> 0,101 g min<sup>-1</sup><em>, </em>Intensidade de Tempo  9,869 min g<sup>-1</sup>, Intensidade de Energia 0,073 Kw h g<sup>-1</sup> e o  menor consumo de energia, 0,1485 KWh, um ganho de eficiência energética de aproximadamente 200 %, contribuindo principalmente com melhorias no P6 da QV.

Circular dichroism and infrared study of β-turn formation in repeat peptides of elastin

1987 ◽  
Vol 52 (5) ◽  
pp. 1356-1361
Author(s):  
S. Abdel Rahman ◽  
M. Elsafty ◽  
A. Hattaba
Keyword(s):  
Circular Dichroism ◽  
Solid State ◽  
Ir Spectra ◽  
Chain Length ◽  
Room Temperature ◽  
Infrared Study ◽  
Feature Characteristic ◽  
C 50 ◽  
The Stability ◽  
Circular Dichroïsm

The conformation of elastin-like peptides Boc-Ala-Pro-Gly-Val-APEGM, Boc-Ala-Pro-Gly-Val-Gly-Val-APEGM, Boc-Ala-Pro-Gly-Val-Ala-Pro-Gly-Val-Gly-Val-APEGM, Boc-Ala-Pro-Gly-Val-Gly-Val-Ala-Pro-Gly-Val-Gly-Val-APEGM were examined in solution using circular dichroism at 30 °C, 50 °C, and 70 °C and in solid state by IR at room temperature. The studies show that the β-turn is a significant conformational feature for peptides under investigation in solution at 30 °C and 50 °C, but at 70 °C the tetra, hexa, and decapeptides show the CD feature characteristic of the β-structure while the dodecapeptide spectra show the presence of β-turn which indicates the stability of the β-turn at this chain length. The IR spectra show that in the solid state at room temperature all investigated peptides assume essentially a β-turn except the tetrapeptide which present evidence of antiparallel β-structure. The β-turn contribution in the IR spectra increases with the increase of the chain length of the peptide.

scholarly journals In Situ Thermal-Stage Fitted-STEM Characterization of Spherical-Shaped Co/MoS2 Nanoparticles for Conversion of Heavy Crude Oils

Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1239
Author(s):  
Manuel Ramos ◽  
Félix Galindo-Hernández ◽  
Brenda Torres ◽  
José Manuel Domínguez-Esquivel ◽  
Martin Heilmaier
Keyword(s):  
Molybdenum Disulfide ◽  
Sodium Molybdate ◽  
Interlayer Spacing ◽  
Scanning Transmission Electron Microscope ◽  
Interplanar Distance ◽  
Scanning Transmission ◽  
Heavy Crude ◽  
C 50 ◽  
Nano Catalysts

We report the thermal stability of spherically shaped cobalt-promoted molybdenum disulfide (Co/MoS2) nano-catalysts from in-situ heating under electron irradiation in the scanning transmission electron microscope (STEM) from room temperature to 550 °C ± 50 °C with aid of Fusion® holder (Protochip©, Inc.). The catalytic nanoparticles were synthesized via a hydrothermal method using sodium molybdate (Na2MoO4·2H2O) with thioacetamide (CH3CSNH2) and cobalt chloride (CoCl2) as promoter agent. The results indicate that the layered molybdenum disulfide structure with interplanar distance of ~0.62 nm remains stable even at temperatures of 550 °C, as observed in STEM mode. Subsequently, the samples were subjected to catalytic tests in a Robinson Mahoney Reactor using 30 g of Heavy Crude Oil (AGT-72) from the golden lane (Mexico’s east coast) at 50 atm using (ultrahigh purity) UHP hydrogen under 1000 rpm stirring at 350 °C for 8 h. It was found that there is no damage on the laminar stacking of Co/MoS2 with temperature, with interlayer spacing remaining at 0.62 nm; these sulfided catalytic materials led to aromatics rise of 22.65% and diminution of asphaltenes and resins by 15.87 and 3.53%, respectively.

Histological and proteome analyses of Microbacterium foliorum-mediated decrease in arsenic toxicity in Melastoma malabathricum

3 Biotech ◽  
2021 ◽  
Vol 11 (7) ◽  
Author(s):  
Sadiya Alka ◽  
Shafinaz Shahir ◽  
Norahim Ibrahim ◽  
Norasfaliza Rahmad ◽  
Norhazalina Haliba ◽  
...  
Keyword(s):  
Arsenic Toxicity ◽  
Melastoma Malabathricum

VP39 The Alphabet Lottery? How NICE Outcomes Vary By Appraisal Committee

2019 ◽  
Vol 35 (S1) ◽  
pp. 86-86
Author(s):  
Richard Macaulay ◽  
Lok Wan Liu ◽  
Cornelia Roibu ◽  
Andrea Berardi
Keyword(s):  
Cost Effectiveness ◽  
The Other ◽  
Appraisal Committee ◽  
Technology Appraisal ◽  
The Public ◽  
Chi Squared ◽  
C 50 ◽  
To Receive ◽  
Disciplinary Group ◽  
53 C 55

IntroductionNICE (National Institute for Health and Care Excellence) makes recommendations on the public reimbursement of medicines based on their clinical- and cost-effectiveness. The recommendation is made by an Appraisal Committee (comprising a multi-disciplinary group of independent experts) as part of a technology appraisal. There are four Appraisal Committees (A,B,C,D); this research investigates whether appraisal outcomes vary by committee.MethodsAll publicly-available Final Appraisal Determinations from NICE Single Technology Appraisals (STA) were screened (01/10/2009-14/11/2018) and key data were extracted. Homogeneity in rates of acceptance or rejection across the committees was assessed using Chi-squared tests.ResultsThe Appraisal Committee was identified for 298 technologies, 56% (168/298) of which were ‘recommended’. The number of technologies assessed by each committee was similar (A:79, B:62, C:91, D:66). However, STAs conducted by Committee D were significantly less likely to receive ‘recommended’ outcomes (A:68% [54/79], B:65% [40/62], C:53% [48/91], D:39% [26/66]; p < 0.01). STAs for oncology indications had higher ’not recommended’ outcomes than those for non-oncology indications (25% vs. 9%). The lower ‘recommendation’ rates for committee D persisted across oncology (A:60%, B:83%, C:50%, D:38%; p = 0.01) and non-oncology indications (A:73%, B:53%, C:55%, D:40%; p < 0.01). However, STAs conducted by Committee D were significantly more likely to receive ‘optimized’ recommendations (A:16%, B:21%, C:33%, D: 36%; p < 0.01) and when considering the rates of ‘recommended’ and ‘optimized’ outcomes compared to ‘only in research’ and ‘not recommended’ outcomes, no significant differences were found (A:85%, B: 85%, C:86%, D:76%; p = 0.27).ConclusionsSTAs undertaken by NICE Appraisal Committee D was associated with a significantly lower rate of ‘recommended’ outcomes but tended to an ‘optimized’ recommendation significantly more than the other committees. Further research is needed to determine if this reflects any deviation in uniform implementation of NICE methodology between Committees.

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