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2021 ◽  
Vol 1 (12) ◽  
pp. 1-62
Author(s):  
Yiglet Mebrat

A Laboratory Manual for the Preparation of Chemical Reagents, Solutions and Special Indicators. ETHIOPIAN BIODIVERSITY INSTITUTE, Microbial Biodiversity Directorate. This manual includes detailed view of the following: Laboratory Safety Precautions, Chemical Reagent Preparation, Buffer and Chemical Solution Preparation, Staining Solution Preparation, Indicators and Dye Solution Preparation, Preparation of Special Reagents, Known and Suspected List of Carcinogens and References.


2021 ◽  
Author(s):  
S.A. Baloch ◽  
J.M. Leon ◽  
S.K. Masalmeh ◽  
D. Chappell ◽  
J. Brodie ◽  
...  

Abstract Over the last few years, ADNOC has systematically investigated a new polymer-based EOR scheme to improve sweep efficiency in high temperature and high salinity (HTHS) carbonate reservoirs in Abu Dhabi (Masalmeh et al., 2014). Consequently, ADNOC has developed a thorough de-risking program for the new EOR concept in these carbonate reservoirs. The de-risking program includes extensive laboratory experimental studies and field injectivity tests to ensure that the selected polymer can be propagated in the target reservoirs. A new polymer with high 2-acrylamido-tertiary-butyl sulfonic acid (ATBS) content was identified, based on extensive laboratory studies (Masalmeh, et al., 2019, Dupuis, et al., 2017, Jouenne 2020), and an initial polymer injectivity test (PIT) was conducted in 2019 at 250°F and salinity >200,000 ppm, with low H2S content (Rachapudi, et al., 2020, Leon and Masalmeh, 2021). The next step for ADNOC was to extend polymer application to harsher field conditions, including higher H2S content. Accordingly, a PIT was designed in preparation for a multi-well pilot This paper presents ADNOC's follow-up PIT, which expands the envelope of polymer flooding to dissolve H2S concentrations of 20 - 40 ppm to confirm injectivity at representative field conditions and in situ polymer performance. The PIT was executed over five months, from February 2021 to July 2021, followed by a chase water flood that will run until December 2021. A total of 108,392 barrels of polymer solution were successfully injected during the PIT. The extensive dataset acquired was used to assess injectivity and in-depth mobility reduction associated with the new polymer. Preliminary results from the PIT suggest that all key performance indicators have been achieved, with a predictable viscosity yield and good injectivity at target rates, consistent with the laboratory data. The use of a down-hole shut-in tool (DHSIT) to acquire pressure fall-off (PFO) data clarified the near-wellbore behaviour of the polymer and allowed optimisation of the PIT programme. This paper assesses the importance of water quality on polymer solution preparation and injection performance and reviews operational data acquired during the testing period. Polymer properties determined during the PIT will be used to optimise field and sector models and will facilitate the evaluation of polymer EOR in other giant, heterogeneous carbonate reservoirs, leading to improved recovery in ADNOC and Middle East reservoirs.


2021 ◽  
pp. 1-225
Author(s):  
Gopi K

The main purpose of this book is focused to motivate the UG and PG students of life sciences to pursuing their research studies. In the higher education Ph.D degree is considered as research study. At the beginning,to the Ph.D study some basic guidance and informations are needed to the research scholars.


2021 ◽  
Vol 8 (2) ◽  
pp. 74-87
Author(s):  
Veselin Dochev

Abstract During the period 2019 - 2020, a study was conducted on soil type calcic chernozem with Venka 1 common winter wheat variety. The experiment is based on the block method, in four replications with a size of the experimental plot of 10 m2. Sowing was carried out in October with a sowing rate of 500 sprouts/m2 after the predecessor sugar beet. In the appropriate periods, treatments were made in 4 variants: 1) Control - untreated variant, 2) Treatment with biodynamic preparations: 500 + Fladen preparation + preparation 501, 3) Treatment with biological preparations: Heliosulfur + Free N. 4) Combined treatment with the same biodynamic and biological preparations. Preparation 500 was applied in the phase of autumn and spring wheat tillering - 5% solution. Preparation 501 was applied in the phase ear formation - 1.5 g for 30 l of water/da. Fladen preparation is applied in the phase of autumn and spring tillering - 1.5% solution. Heliosulfur was applied in the ear formation phase - flowering at a dose of 50 ml/da, at an appropriate date on the biodynamic calendar. Free N was applied to the soil in the phase of autumn and spring tillering at a dose of 50 ml/da, at an appropriate date on the biodynamic calendar. The analysis of the technological qualities is made according to the respective ISO methodology. The statistical data processing was performed with the STATGRAPH program. The application of biodynamic and biological preparations and their joint use leads to an increase in the yield of wet gluten, as well as an increase in the content of N, P, K and protein in wheat grain. It has been proven that the combined use of biodynamic and biological preparations increases the content of dry matter, organic matter and the content of nitrogen-free extracts in wheat grain. The content of crude proteins has been shown to increase only in the varieties treated with biodynamic and biological preparations.


2021 ◽  
Vol 8 (2) ◽  
pp. 88-99
Author(s):  
Veselin Dochev

Abstract During the period 2019 - 2020, a study was conducted on soil type calcic chernozem with Kolorit triticale variety. The experiment is based on the block method, in four replications with a size of the experimental plot of 10 m2. Sowing was carried out in October with a sowing rate of 500 sprouts/m2 after the predecessor sugar beet. In the appropriate periods, treatments were made in 4 variants: 1) Control - untreated variant, 2) Treatment with biodynamic preparations: 500 + Fladen preparation + preparation 501, 3) Treatment with biological preparations: Heliosulfur + Free N, 4) Combined treatment with the same biodynamic and biological preparations. Preparation 500 was applied in the phase of autumn and spring triticale tillering - 5% solution. Preparation 501 was applied in the phase of ear formation - 1.5 g for 30 l of water/da. Fladen preparation was applied in the phase of autumn and spring tillering - 1.5% solution. Heliosulfur was applied in the ear formation phase - flowering at a dose of 50 ml/da, on an appropriate date on the biodynamic calendar. Free N was applied to the soil in the phase of autumn and spring tillering at a dose of 50 ml/da, on an appropriate date on the biodynamic calendar. The analysis of the technological qualities is made according to the respective ISO methodology. The statistical data processing was performed with the STATGRAPH program. The application of biodynamic and biological preparations and their joint use leads to an increase in the content of Nitrogen-free Extracts, an increase in the content of Minerals and Ca in the variant treated with a combination of biodynamic and biological preparations. Treatment with biodynamic preparations has been shown to increase the dry matter and organic matter content of the grain, while when compared to the control one, a difference in the same indicators has been observed only in the second year of the experiment with biological preparations. Treatment with biodynamic and biological preparations and their joint use did not affect the content of N, P and K.


Author(s):  
Laura Wienands ◽  
Franziska Theiß ◽  
James Eills ◽  
Lorenz Rösler ◽  
Stephan Knecht ◽  
...  

AbstractParahydrogen-induced polarization is a hyperpolarization method for enhancing nuclear magnetic resonance signals by chemical reactions/interactions involving the para spin isomer of hydrogen gas. This method has allowed for biomolecules to be hyperpolarized to such a level that they can be used for real time in vivo metabolic imaging. One particularly promising example is fumarate, which can be rapidly and efficiently hyperpolarized at low cost by hydrogenating an acetylene dicarboxylate precursor molecule using parahydrogen. The reaction is relatively slow compared to the timescale on which the hyperpolarization relaxes back to thermal equilibrium, and an undesirable 2nd hydrogenation step can convert the fumarate into succinate. To date, the hydrogenation chemistry has not been thoroughly investigated, so previous work has been inconsistent in the chosen reaction conditions in the search for ever-higher reaction rate and yield. In this work we investigate the solution preparation protocols and the reaction conditions on the rate and yield of fumarate formation. We report conditions to reproducibly yield over 100 mM fumarate on a short timescale, and discuss aspects of the protocol that hinder the formation of fumarate or lead to irreproducible results. We also provide experimental procedures and recommendations for performing reproducible kinetics experiments in which hydrogen gas is repeatedly bubbled into an aqueous solution, overcoming challenges related to the viscosity and surface tension of the water.


2021 ◽  
Vol 141 (3) ◽  
pp. 403-413
Author(s):  
Mizuho Shibata ◽  
Yuka Kobayashi ◽  
Yoko Niibe ◽  
Kenichi Arai ◽  
Takako Nakamura ◽  
...  

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 338
Author(s):  
Martha Kafetzi ◽  
Stergios Pispas

In this work, the synthesis and the aqueous solution self-assembly behavior of novel partially hydrophobically modified poly(2-(dimethylamino) ethyl methacrylate)-b-poly(oligo(ethylelene glycol) methyl ether methacrylatetabel) pH and temperature responsive random diblock copolymers (P(DMAEMA-co-Q6/12DMAEMA)-b-POEGMA), are reported. The chemical modifications were accomplished via quaternization with 1-iodohexane (Q6) and 1-iodododecane (Q12) and confirmed by 1H-NMR spectroscopy. The successful synthesis of PDMAEMA-b-POEGMA precursor block copolymers was conducted by RAFT polymerization. The partial chemical modification of the diblocks resulted in the permanent attachment of long alkyl chains on the amine groups of the PDMAEMA block and the presence of tertiary and quaternary amines randomly distributed within the PDMAEMA block. Light scattering techniques confirmed that the increased hydrophobic character results in the formation of nanoaggregates of high mass and tunable pH and temperature response. The characteristics of the aggregates are also affected by the aqueous solution preparation protocol, the nature of the quaternizing agent and the quaternization degree. The incorporation of long alkyl chains allowed the encapsulation of indomethacin within the amphiphilic diblock copolymer aggregates. Nanostructures of increased size were detected due to the encapsulation of indomethacin into the interior of the hydrophobic domains. Drug release studies demonstrated that almost 50% of the encapsulated drug can be released on demand by aid of ultrasonication.


2021 ◽  
Vol 214 ◽  
pp. 273-285
Author(s):  
Sylwia Mozia ◽  
Paulina Sienkiewicz ◽  
Kacper Szymański ◽  
Dominika Darowna ◽  
Adam Czyżewski ◽  
...  

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