pH-dependent release of elements from hardened and non-hardened wood ash

SummaryTreatment of human and dog oxalated plasma with 0.2 to 1.0 × 10−1 M 2.3-dithiopropanol (BAL) or dithiothreitol (DTT) at 2–4° C for 30 min results in the reduction of the vitamin-K dependent clotting factors II, VII, IX and X to the respective-SH derivatives. The reaction is pH dependent. Under aerobic conditions the delayed one stage prothrombin time can be partly reversed. Under anaerobic conditions a gradual prolongation of the one stage prothrombin time occurs without reversal.In very diluted plasma treated with the dithiols, prothrombin can be converted into thrombin if serum as source of active factors VII and X is added. In contrast SH factors VII, IX and X are inactive in the specific tests. Reoxidation to active factors II, VII, IX and X takes place during adsorption and elution of the SH derivatives. The experiments have indicated that not only factor II but also factors VII, IX and X have active-S-S-centres.

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A BRIEF STUDY ON THE STRENGTH PROPERTIES OF CONCRETE BY PARTIAL REPLACEMENT OF CEMENT WITH WOOD ASH AND NATURAL SAND WITH 100 PERCENT CRUSHED STONE SAND

International Journal of Research in Engineering and Technology ◽

10.15623/ijret.2017.0614001 ◽

2017 ◽

Vol 06 (14) ◽

pp. 1-7

Author(s):

J.Geetanjali .

Keyword(s):

Strength Properties ◽

Wood Ash ◽

Crushed Stone ◽

Partial Replacement ◽

Natural Sand

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Rationalizing the pH-Activity Response for Escherichia Coli’s Glycinamide Ribonucleotidetransformylase Through Computational Methods

10.26434/chemrxiv.7985618.v1 ◽

2019 ◽

Author(s):

Adrian Roitberg ◽

Pancham Lal Gupta

Keyword(s):

Transfer Reaction ◽

Catalytic Mechanism ◽

Ph Dependence ◽

Ph Effects ◽

Dependent Manner ◽

E Coli ◽

Gar Tfase ◽

Activity Curve ◽

Ph Dependent ◽

Formyl Transfer

<div>Human Glycinamide ribonucleotide transformylase (GAR Tfase), a regulatory enzyme in the de novo purine biosynthesis pathway, has been established as an anti-cancer target. GAR Tfase catalyzes the formyl transfer reaction from the folate cofactor to the GAR ligand. In the present work, we study E. coli GAR Tfase, which has high sequence similarity with the human GAR Tfase with most functional residues conserved. E. coli GAR Tfase exhibits structural changes and the binding of ligands that varies with pH which leads to change the rate of the formyl transfer reaction in a pH-dependent manner. Thus, the inclusion of pH becomes essential for the study of its catalytic mechanism. Experimentally, the pH-dependence of the kinetic parameter kcat is measured to evaluate the pH-range of enzymatic activity. However, insufficient information about residues governing the pH-effects on the catalytic activity leads to ambiguous assignments of the general acid and base catalysts and consequently its catalytic mechanism. In the present work, we use pH-replica exchange molecular dynamics (pH-REMD) simulations to study the effects of pH on E. coli GAR Tfase enzyme. We identify the titratable residues governing the pH-dependent conformational changes in the system. Furthermore, we filter out the protonation states which are essential in maintaining the structural integrity, keeping the ligands bound and assisting the catalysis. We reproduce the experimental pH-activity curve by computing the population of key protonation states. Moreover, we provide a detailed description of residues governing the acidic and basic limbs of the pH-activity curve.</div>

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Pengaruh Penambahan Abu Kayu Dan Abu Bambu Terhadap Kepadatan Tanah Lempung

Jurnal Manajemen Teknologi & Teknik Sipil ◽

10.30737/jurmateks.v3i2.1077 ◽

2020 ◽

Vol 3 (2) ◽

pp. 191

Author(s):

Vella Maulina Kris Putri ◽

Agata Iwan Candra ◽

Ahmad Ridwan

Keyword(s):

Surface Runoff ◽

Clay Soil ◽

Wood Ash ◽

Road Surface ◽

Plastic Limit ◽

Test Items ◽

Native Soil

The soil has an important role in construction, namely as the loading of soil on clay. It is necessary to improve the nature of the shrinkage. The authors conducted the study to increase the strength of clay by adding wood ashes and bamboo ashes. Wood ash and bamboo ash have pozzolan properties expected to add power to clay when weighted, would drop significantly. Material compares in this study using a mix of wood ash and bamboo ash with a variation of 0%, 4%, 8%, and 12%. Meanwhile, the clay soil is taken directly from the ravaged area, from bulging villages, from the grid district. The results showed that the soil is categorized as montmorillonite soil with properties that can damage light structures and road surface runoff. After adding wood and bamboo ash, it showed optimum results of 12% of the dry fixed test items showing a liquid limit’s value at 41,00%, plastic limit at 28,43%, and the net value of plastic limit at 12,57%. When testing for solidification using native soil at a dry volume of 7,91, gr/cm rainfall can increase by 10,42 gr/cm additives after adding 12% of wood ash and bamboo ash.Tanah memiliki peran penting dalam konstruksi yaitu sebagai pembebanan tanah pada tanah liat. Perlu untuk memperbaiki sifat penyusutan. Penulis melakukan penelitian untuk meningkatkan kekuatan tanah liat dengan cara menambahkan abu kayu dan abu bambu. Abu kayu dan abu bambu memiliki sifat pozzolan yang diharapkan dapat menambah kekuatan pada tanah liat saat tertimbang, akan turun secara signifikan. Perbandingan material dalam penelitian ini menggunakan campuran abu kayu dan abu bambu dengan variasi 0%, 4%, 8%, dan 12%. Sementara itu, tanah lempung diambil langsung dari area yang rusak, dari desa-desa yang menggembung, dari grid distrik. Hasil penelitian menunjukkan bahwa tanah tersebut dikategorikan sebagai tanah montmorillonite dengan sifat yang dapat merusak struktur ringan dan aliran permukaan jalan. Setelah dilakukan penambahan abu kayu dan bambu didapatkan hasil optimum dari 12% benda uji tetap kering yang menunjukkan nilai batas cair 41,00%, batas plastis 28,43%, dan nilai bersih batas plastis 12,57%. Pada pengujian solidifikasi menggunakan tanah asli pada volume kering 7,91 gr / cm curah hujan dapat meningkat sebesar 10,42 gr / cm aditif setelah penambahan 12% abu kayu dan abu bambu.

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