Academic literature on the topic 'Indicators and Reagents'
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Journal articles on the topic "Indicators and Reagents"
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Mebrat, Yiglet. "A Laboratory Manual for the Preparation of Chemical Reagents, Solutions and Special Indicators." Cognizance Journal of Multidisciplinary Studies 1, no. 12 (December 30, 2021): 1–62. http://dx.doi.org/10.47760/cognizance.2021.v01i12.001.
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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.
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Sviridov, A. V., V. V. Iurchenko, I. K. Gindulin, and M. S. Roschina. "The use of high-fine modified aluminosilicate adsorbents in the processes of purification of household waste water." Proceedings of the Voronezh State University of Engineering Technologies 83, no. 4 (January 17, 2022): 274–79. http://dx.doi.org/10.20914/2310-1202-2021-4-274-279.
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The article deals with the problem of treatment and purification of domestic waste water. Today, many treatment facilities do not have a reagent treatment system and are limited only by mechanical and biological methods of water treatment. We have considered the possibility of using a new scheme for reagent treatment of domestic wastewater. The existing reagent treatment at treatment facilities does not always cope with the tasks of water treatment. It is not possible to achieve the required values for many indicators: COD, residual phosphate content, residual iron content, etc. The water under study was treated with traditional coagulants (iron chloride and aluminum sulfate) and new highly dispersed modified aluminosilicate adsorbents of the KS brand. Lime and alkali were used as alkalizing reagents. A feature of KS grade reagents is their high coagulation-adsorption activity in relation to the extracted components. This is due to the high activity of modifiers on the surface of the aluminosilicate matrix. In the course of the study, a coagulation-flocculation experiment was carried out. During the purification process, the water was examined for the residual content of various components: pH, phosphates, ammonium nitrogen, chlorides, and iron. Effective dosages have been established for each of the reagents used and the possibility of using reagents for the treatment of domestic wastewater to the required standards has been shown. Traditional reagents have shown insufficient efficiency in wastewater treatment. When using iron chloride and aluminum sulfate, it is not possible to reduce the phosphate content to the required values. For the KS reagent, the effective dose was 40 mg / dm3 with the combined use of lime at a dose of 30 mg/dm3
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Krasavtseva, E. A., L. A. Ivanova, A. V. Svetlov, and D. V. Makarov. "Biotesting of Binding Reagents for Dust Suppression on Rare Metal Tailings Waste in the Arctic Zone of the Russian Federation." Ecology and Industry of Russia 27, no. 12 (December 12, 2023): 15–20. http://dx.doi.org/10.18412/1816-0395-2023-12-15-20.
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The paper presents the results of environment safety assessment of Russian and foreign binding reagents (Syntex-65, Lukoil DD 3000, Voltes PP-300 and Dustbind) used for remediation of objects of accumulated environmental damage in the Murmansk region. The paper shows that in the presence of anti-erosion and water-retentive phytocenosis on technosoil of loparite ore tailings, these reagents have a partial inhibitory effect on the first first seedlings of timothy grass (Phleum pratense L.) and red fescue (Festuca rubra L.) and statistically (p <0.005) affect its main quality indicators (plant height and biomass). Effective methods of applying reagents to the dusty surface of technosoil were identified. When using the Lukoil DD 3000 reagent as an analogue of Dustbin – continuous, for Voltes PP-300 – fragmentary, when using Syntex-65 – continuous in the mode of simulated hydroseeding.
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Xu, Hongxiang, Jiahua Cui, Yijun Cao, Lin Ma, Guixia Fan, Gen Huang, Kejia Ning, et al. "Construction of a Green-Comprehensive Evaluation System for Flotation Collectors." Processes 11, no. 5 (May 19, 2023): 1563. http://dx.doi.org/10.3390/pr11051563.
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The evaluation of flotation reagents performs an important role in the selection and green application of reagents. The green indexes and effect indexes of flotation collectors were selected by data literature method, system analysis method, mathematical model method, and qualitative and quantitative analysis method, and the green evaluation system of flotation collectors, flotation effect evaluation system, and comprehensive evaluation system of flotation collectors were established. The normalization method and expert evaluation methods were adopted to obtain the grade classification of quantitative and qualitative indicators, respectively. The analytic hierarchy process (AHP) was used to determine the weight of secondary indicators and tertiary indicators of the evaluation system and the weight of indicators at a lower level. Applying the fuzzy comprehensive evaluation (FCE), the trapezoidal function is selected to determine the index affiliation, the index system score is calculated according to the weighted average principle, and finally, the established evaluation system is applied in an example. The example application shows that the comprehensive evaluation system of flotation collectors can make a comprehensive evaluation of collectors from the aspects of the greenness of reagent, flotation effect, and cost, and it has a strong target and practicality for collectors evaluation. The establishment of the system has a guiding significance for the selection and use of flotation collectors.
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Yalaletdinova, Alina, Maria Malkova, Margarita Vozhdaeva, Pavel Serebryakov, Olga Kantor, and Evgeny Kantor. "Prediction of optimal coagulant and flocculant dosage for water treatment at surface water intake." E3S Web of Conferences 480 (2024): 02009. http://dx.doi.org/10.1051/e3sconf/202448002009.
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Reagent treatment is one of the main methods of source water treatment in water supply plants. Suitable values of coagulant and flocculant doses, as a rule, are selected experimentally, and do not vary depending on seasonal changes in indicators. Therefore, to achieve high efficiency of water treatment, there is a need to determine the doses of coagulant and flocculant for the whole year and for separate seasonal periods in order to compare them. Regression analysis allowed us to quantitatively describe the relationships between turbidity, color, oxidizability and hardness of the source water and reagent doses. At the same time the significance of the influence of the listed indicators on the value of coagulant and flocculant doses was determined. The multifactorial relationship between the water quality indicators at the water source (turbidity, color, oxidizability and general hardness) and the parameters of water treatment processes (dosage of coagulant and flocculant) was studied for both the annual cycle and for specific shorter time periods. Calculation of coagulant and flocculant doses for the entire annual period of the water source in practice, makes it possible to predict suitable doses of reagents before trial coagulation. The equations obtained for individual periods take into account the influence of individual factors, and, therefore, will allow to increase the efficiency of water treatment process control, reduce the consumption of reagents and significantly increase the barrier role of water treatment facilities.
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Kondratev, Sergey, and Tatyana Khamzina. "Assessment of collecting activity of physically sorbed reagents on the example of easily floatable coking coal sludge." Записки Горного института 256 (November 10, 2022): 549–59. http://dx.doi.org/10.31897/pmi.2022.52.
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The article presents one of the new approaches to theoretical assessment of collecting ability of reagents. The efficiency of reagents-collectors with different chemical composition used for flotation of coking coals was studied. A comparative assessment of the flotation activity of kerosene, mineral oil, thermal gas oil, KETGOL and FLOTEK is given. The criteria of collecting activity of the above reagents-collectors for coal sludge flotation were specified. A correlation was established between the indicators of coal sludge flotation by the above reagents and their physical parameters. It is shown that the rate of spreading over water surface can characterize the flotation activity of reagents. Based on dependence of the collecting activity of a reagent on its rate of spreading along the “gas – liquid” interface and surface pressure, the main approaches to determining the structure and composition of molecules of an effective flotation collector can be determined. A new concept of the function performed by a physically sorbed collector in the elementary act of flotation and a criterion for the flotation activity of reagents used in coal sludge beneficiation are proposed. It is shown that the collector used in coal flotation, in addition to hydrophobizing the surface of the extracted particles, should reduce the induction time and remove the kinetic constraint on formation of a flotation aggregate.
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BURDONOV, Aleksander, Nadezhda VCHISLO, Vyacheslav BARAKHTENKO, and Tatiana SAHABUTDINOVA. "Synthesized collectors flotation activity study based on fluorine containing and acetylene alcohols." Sustainable Development of Mountain Territories 15, no. 3 (September 30, 2023): 707–19. http://dx.doi.org/10.21177/1998-4502-2023-15-3-707-719.
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Introduction. The article describes the problem of low quality mineral raw materials used for gold mining and considers the possibilities of increasing the efficiency of the technological process of beneficiation of refractory ores. As a result of the study, studies were carried out to study the flotation activity of new collecting reagents and their effect on the surface of sulfide gold-bearing minerals was studied. Research methods and materials. The methods used in the work were NMR, atomic absorption and ultraviolet spectroscopy, electron microscopy, laser diffraction, ore preparation, flotation, and electrophoretic light scattering. To determine the assessment of flotation activity as heteropolar collectors for the flotation of sulfide minerals, a number of synthesized compounds were used: 2-methyl-3-butyn-2-ol, 5-dimethyl-4-methylidene-1,3-oxathiolane-2-thione and 2. 2,3,3,4,4,5,5-octafluoropentyl sodium xanthate. Sulfide ore was used to conduct laboratory flotation studies; the monomineral pyrite was used to study the sorption of the reagent and determine the zeta potential of the surface. The following reagents were also used in the experiment: activator – copper sulfate; heteropolar collectors – potassium butylxanthate (BCX), sodium dialkyldithiophosphate (BTF-1552); organic carbon depressor – beta-sulfonaphthalene formaldehyde sodium salt (oroflos D); blowing agent – methyl isobutyl carbinol (MIBC). Research results and discussion. The synthesis of collecting reagents based on various chemical reactions was carried out and their flotation activity was studied. Several promising compounds have been obtained that have shown results when used as heteropolar collectors for the flotation of sulfide minerals. The research results showed that one of the synthesized reagents, 2-methyl-3-butyn-2-ol, has a positive effect on gold recovery during flotation. This reagent increases recovery by 0.18% and 1.46% when used together with other reagents. It also increases recovery by 1.81% when used alone. This suggests that 2-methyl-3-butyn-2-ol can be used as a replacement for one of the main heteropolar collectors. Determination of UV spectra showed the sorption of 2-methyl-3-butyn-2-ol on the surface of pyrite with an amount of up to 2.388·10-5 mol/m2 depending on the initial concentration of the reagent. The results of determining the zeta potential showed that the reagents significantly reduce this indicator, indicating electrostatic interaction and adsorption of the reagents on the pyrite surface. Conclusion. Overall, this paper describes the development of new harvesting reagents and their effects on the surface of sulfide gold-bearing minerals. The results of the study suggest the possibility of using 2-methyl-3-butyn-2-ol as a replacement for one of the main collectors in flotation. Resume. The article presents the results of studies assessing the flotation activity of a number of synthesized compounds: 2-methyl-3-butyn-2-ol, 5-dimethyl-4-methylidene-1,3-oxathiolan-2-thione and 2,2,3,3 ,4,4,5,5-octafluoropentyl sodium xanthate. The best technological performance during laboratory flotation was found for the reagent 2-methyl-3-butyn-2-ol; the extraction of gold into the concentrate was 84.68%, the content was 10.2%. For this compound, its amount adsorbed on the surface of pyrite was determined to be up to 2.388·10-5 mol/m2 in experiments. A low negative charge on the surface of pyrite was revealed after mixing it with reagent solutions when determining the zeta potential. Suggestions for practical applications and directions for future research. The results of the work can be recommended for further pilot tests with the subsequent development of technology for the industrial production of these reagents in the case of improved technological indicators of flotation gold extraction.
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Shevchenko, A. P., I. A. Manachyn, B. W. Dvoskin, V. G. Kislyakov, A. S. Vergun, S. A. Shevchenko, V. P. Petrusha, and A. M. Bashmakov. "Calculation and analytical evaluation and industrial verification of the indicators of ladle desulfuration of cast iron using different reagents." Fundamental and applied problems of ferrous metallurgy, no. 34 (2020): 73–89. http://dx.doi.org/10.52150/2522-9117-2020-34-73-89.
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The necessity of an integrated approach in assessing and choosing a technology for secondary desulfurization of cast iron has been substantiated. It is shown that one of the main parameters and indicators is the consumption of the reagent, which determines all the main indicators of the process. A comparative analysis of the indicators in Table 1 also indicates that in the KR process, an increase in the mass of pig iron in the ladle reduces the desulfurization efficiency, since the transition from a ladle with a mass of 80 and 100 tons of pig iron to large ladles (260 tons) is accompanied by a decrease in the specific degree of desulfurization, removal increases the consumption of the reagent per unit of sulfur removed. Significant specific consumption of reagents (up to 8-17 kg / t of cast iron) and the duration of mixing (up to 8-20 minutes), as well as the cycle - up to 25-68 minutes, which causes tangible losses in the temperature of the cast iron - on average 40-42 ° С, and in a number of desulfurization modes - up to 92-128 °С. This is due to the fact that with an increase in the mass of cast iron, the mass transfer processes between the slag and the molten iron of the ladle deteriorate. The highest specific consumption of reagents in the KR-process ultimately determined the highest costs in the implementation of this process. The lowest specific costs for monoinjection of magnesium predetermine the lowest costs for the industrial development of this process. Actual indicators of industrial blowdowns indicate ohm. that monoinjection of granular magnesium is characterized by the lowest consumption of reagents - on average 0.42-0.55 kg / t of cast iron, the shortest duration of the desulfurization operation - on average 5.5-7.7 minutes and at the same time providing up to super deep desulfurization of cast iron - up to 0.0003–0.001%, desulfurization degree - up to 99%, high sulfur removal rate - on average 12–14.4% / min, high reagent assimilation rate - on average 75–92%. The actual data on the technology applied KR-processes (CaO + CaF2), co-injection of lime with magnesium (CaO + Mg) and monoinjection of granular magnesium according to the Ukrainian injection technology are presented. The costs of desulfurization by KR processes - koninjection - monoinjection are in the ratio 3: 2: 1. The advantage of injection processes of cast iron desulfurization has been substantiated.
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Vertiprakhov, Vladimir, Alena Grozina, Vladimir Fisinin, Natalya Ovchinnikova, and Anatoly Bittirov. "Impact of various reagents during blood collection from poultry to analyze morpho-biochemical indicators." E3S Web of Conferences 262 (2021): 02009. http://dx.doi.org/10.1051/e3sconf/202126202009.
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The work provides experimental data on the impact of anticoagulants (K3 - EDTA, 3.8% sodium citrate and lithium heparin) and coagulation activator on morpho-biochemical indicators in the blood samples of broiler chickens of cross-selection of Agricultural Center “Smena” at the age of 35 days. The studies were carried out with the use of semi-automatic flow analyzer Sinnowa BS-3000P (SINNOWA Medical Science & Technology Co., Ltd, China) and veterinary automatic blood analyzer DF-50 by Dymind Biotech (PRC) with the use of original reagents. The results showed that the most optimal reagent for determination of morphological indicators of the poultry blood was EDTA. The average white blood count (WBC) is lower in blood samples with citrate and heparin in contrast to EDTA by 30.5% and 24.1%, respectively. The average red blood count (RBC) is lower in tubes with sodium citrate (by 37.9 %) and lithium heparin (by 13.8 %) in contrast to K3-EDTA. When the sodium citrate anticoagulant is used, the blood biochemistry results for all positions of the experiment, excluding calcium, are lower than in heparin, and its closest values are lower than in coagulation activator, excluding trypsin activity. That’s why, the most optimal reagents for biochemistry, including for blood enzyme tests, should be considered the tubes with heparin or coagulation activator.
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Pyka, Alina. "Detection Progress of Selected Drugs in TLC." BioMed Research International 2014 (2014): 1–19. http://dx.doi.org/10.1155/2014/732078.
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This entry describes applications of known indicators and dyes as new visualizing reagents and various visualizing systems as well as photocatalytic reactions and bioautography method for the detection of bioactive compounds including drugs and compounds isolated from herbal extracts. Broadening index, detection index, characteristics of densitometric band, modified contrast index, limit of detection, densitometric visualizing index, and linearity range of detected compounds were used for the evaluation of visualizing effects of applied visualizing reagents. It was shown that visualizing effect depends on the chemical structure of the visualizing reagent, the structure of the substance detected, and the chromatographic adsorbent applied. The usefulness of densitometry to direct detection of some drugs was also shown. Quoted papers indicate the detection progress of selected drugs investigated by thin-layer chromatography (TLC).
Dissertations / Theses on the topic "Indicators and Reagents"
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García, Elena. "Reagent storage and transport in microfluidic systems for clinical diagnostic and drug discovery purposes /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/7991.
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Pauff, Steven M. "Advancements in the Synthesis and Application of Near-Infrared Imaging Reagents: A Dissertation." eScholarship@UMMS, 2015. https://escholarship.umassmed.edu/gsbs_diss/751.
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Fluorescence-based imaging techniques provide a simple, highly sensitive method of studying live cells and whole organisms in real time. Without question, fluorophores such as GFP, fluorescein, and rhodamines have contributed vastly to our understanding of both cell biology and biochemistry. However, most of the fluorescent molecules currently utilized suffer from one major drawback, the use of visible light. Due to cellular autofluorescence and the absorbance of incident light by cellular components, fluorescence imaging with visible wavelength fluorophores often results in high background noise and thus a low signal-to-noise ratio. Fortunately, this situation can be ameliorated by altering the wavelength of light used during imaging. Near-infrared (NIR) light (650-900 nm) is poorly absorbed by cells; therefore, fluorophores excited by this light provide a high signal-to-noise ratio and low background in cellular systems. While these properties make NIR fluorophores ideal for cellular imaging, most currently available NIR molecules cannot be used in live cells. The first half of this thesis addresses the synthetic difficulties associated with preparing NIR fluorophores that can be used within living systems. Small molecule NIR fluorophores are inherently hydrophobic which makes them unsuitable for use in the aqueous environment of the cell. Water-solubility is imparted to these dyes through highly polar sulfonates, which subsequently prevents the dyes from entering the cell. The novel work presented here details vii synthetic routes to aid in the development of sulfonated NIR fluorophores, which can be delivered into live cells through the inclusion of an esterase-labile sulfonate protecting group. Application of these synthetic techniques should allow for the development of novel NIR fluorophores with intracellular applications. The second half of this thesis addresses the need for novel NIR imaging reagents. Although several classes of NIR scaffolds do exist, most NIR probes are derivatives of a single class, heptamethine indocyanines. The work described here increases this palette by displaying the ability of NIR oxazines to function as an imaging reagent in live cells and in vivo and as a molecular sensor of biologically-relevant environmental conditions. Combined, the work contained herein has the capacity to not only advance the current NIR toolkit, but to expand it so that fluorescence imaging can move out of the dark and into the NIR light.
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Pauff, Steven M. "Advancements in the Synthesis and Application of Near-Infrared Imaging Reagents: A Dissertation." eScholarship@UMMS, 2001. http://escholarship.umassmed.edu/gsbs_diss/751.
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Fluorescence-based imaging techniques provide a simple, highly sensitive method of studying live cells and whole organisms in real time. Without question, fluorophores such as GFP, fluorescein, and rhodamines have contributed vastly to our understanding of both cell biology and biochemistry. However, most of the fluorescent molecules currently utilized suffer from one major drawback, the use of visible light. Due to cellular autofluorescence and the absorbance of incident light by cellular components, fluorescence imaging with visible wavelength fluorophores often results in high background noise and thus a low signal-to-noise ratio. Fortunately, this situation can be ameliorated by altering the wavelength of light used during imaging. Near-infrared (NIR) light (650-900 nm) is poorly absorbed by cells; therefore, fluorophores excited by this light provide a high signal-to-noise ratio and low background in cellular systems. While these properties make NIR fluorophores ideal for cellular imaging, most currently available NIR molecules cannot be used in live cells. The first half of this thesis addresses the synthetic difficulties associated with preparing NIR fluorophores that can be used within living systems. Small molecule NIR fluorophores are inherently hydrophobic which makes them unsuitable for use in the aqueous environment of the cell. Water-solubility is imparted to these dyes through highly polar sulfonates, which subsequently prevents the dyes from entering the cell. The novel work presented here details vii synthetic routes to aid in the development of sulfonated NIR fluorophores, which can be delivered into live cells through the inclusion of an esterase-labile sulfonate protecting group. Application of these synthetic techniques should allow for the development of novel NIR fluorophores with intracellular applications. The second half of this thesis addresses the need for novel NIR imaging reagents. Although several classes of NIR scaffolds do exist, most NIR probes are derivatives of a single class, heptamethine indocyanines. The work described here increases this palette by displaying the ability of NIR oxazines to function as an imaging reagent in live cells and in vivo and as a molecular sensor of biologically-relevant environmental conditions. Combined, the work contained herein has the capacity to not only advance the current NIR toolkit, but to expand it so that fluorescence imaging can move out of the dark and into the NIR light.
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Castro, Lilian Cristina Menegon. "Avaliação de indicadores biológicos na validação de processos de esterilização de isoladores por peróxido de hidrogênio." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-14062016-184137/.
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A resistência de cinco microrganismos presentes na microbiota da área de produção estéril (Cristalização Estéril), frente a ação do gás de peróxido de hidrogênio foi determinada e o valor O obtido para cada microrganismo foi comparado ao valor D do Bacillus stearothermophilus ATCC 12980 exposto ao mesmo agente. Os microrganismos testados foram Bacillus sp, M. luteus, Corynebacterium, Staphylococcus sp e Penicillium sp. Este teste tinha a finalidade de comprovar que a resistência do Bacillus stearothermophilus é maior quando da exposição ao peróxido de hidrogênio se comparada a outros microrganismos presentes na área produtiva. A metodologia consistiu da inoculação de 0,01 mL da suspensão de cada microrganismo na contagem de 102UFC/0,01 mL em cupons de aço inoxidável, previamente esterilizados por calor seco e posterior exposição ao gás de peróxido de hidrogênio. O experimento demonstrou que o valor D obtido para o Bacillus stearothermophilus ésuperior aos obtidos para os outros microrganismos em teste comprovando que a escolha deste microrganismo para o desafio contra o peróxido de hidrogênio é apropriada. Também executou-se o teste que visava garantir que o aço inoxidável é o material de suporte mais recomendado para este fim, utilizando-se suportes de diversos materiais normalmente encontrados no interior dos isoladores (PVC, aço inoxidável, CKC, teflon, polipropileno, látex, silicone, Hypalon, vidro, nylon, saco de alumínio) com 0,01 mL de inóculo de Bacillus stearothermophilus na contagem de 102UFC/O,01 mL, o que foi devidamente comprovado.The resistance of tive microrganisms found in the sterile production area (Crystallization Area) flora was tested against the hydrogen peroxide gas and the D value of each microrganism was compared to the Bacillus stearothermophilus D Value ATCC 12980 exposed to the same agent. The microrganisms tested were Bacillus sp, M. luteus, Corynebacterium, Staphylococcus sp e Penicillium sp. The purpose of this test was to prove that the resistance of Bacillus stearothermophilus against the exposition the hydrogen peroxide is higher when compared to others microrganisms found in the production area. The methodology consisted in inoculating 0.01 mL of microrganisms suspension with 102UFC/0,01 mL count in stainless steel coupons, treated previously with dry heat and further exposition to the hydrogen peroxide. The experiment demonstrated that the Bacillus stearothermophilus D value is higher against all others microrganisms tested proving that the use of this microrganism for the challenge is appropriate. It was also pertormed a test to guarantee that the stainless steel support is the most recommended one for this purpose, using supports of different materials normally found in the interior of the isolators (PVC, stainless steel, CKC, Teflon, polypropylene, latex, silicon, Hypalon, glass, nylon, aluminum foil) with 0,01 mL Bacillus stearothermophilus inoculum with the count of 102UFC/O,01 mL, that was properly veritied.
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Ishii, Marina. "Aplicação da proteína verde fluorescente (GFPuv) como indicador biológico na validação da autoclavação de soluções parenterais e da esterilização por óxido de etileno de itens termolábeis. Comparação com esporos de Bacillus subtilis." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9135/tde-23082017-115802/.
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A Proteína Verde Fluorescente recombinante, GFPuv, é um sistema marcador atrativo pois, sua presença pode ser visualizada através da intensidade de fluorescência emitida, sem o uso de substratos ou meios complexos. Sendo uma molécula estável à presença de substâncias orgânicas, temperaturas acima de 70°C e ampla faixa de pH, é um potencial Indicador Biológico (IH) para diversas aplicações. A estabilidade térmica da GFPuv, foi avaliada pela medida da perda de intensidade de fluorescência, expressa em valores D (min), tempo de exposição necessário para redução de 90% da intensidade de fluorescência inicial da GFPuv. GFPuv (3,5-9,0 µg/mL), expressa por E. coli e isolada por extração de Partição em Três Fases (TPP) e purificação por Cromatografia de Interação Hidrofóbica (IDC), foi diluída nas soluções parenterais preparadas em tampão (10 mM cada: Tris-EDTA, pH 8; Fosfato, pH 6 e 7, e Acetato, pH 5) e em água para injeção, WFI; pH = 6,70±0,40), e expostas a temperaturas de 25°C e ao intervalo entre 80°C e 100°C. A 95°C, os valores D para a GFPuv em soluções de 1,5% a 50% de glicose variaram de: (i) 1,63 (±0,23) min em acetato pH 5; (ii) 2,64 ± 0,26 min em WFI; (iii) 2,50 ± 0,18 min em fosfato pH 6; (iv) 3,24 ± 0,28 min em fosfato pH 7 e, (v) 2,89 ± 0,44 min em Tris-EDTA pH 8. Cloreto de sódio associado aos tampões proporcionou influência positiva na estabilidade da GFPuv, sendo que em soluções de Tris-EDTA, a adição de 15-20% de NaCl dobrou a estabilidade térmica da GFPuv (valores D de 65,79 min e 18,12 min a 80 °C e 85°C) em relação à solução sem cloreto de sódio. Nos processos de esterilização por óxido de etileno (45°C-60°C), a GFPuv pode ser utilizada como IB para monitorar a distribuição de gás dentro da câmara, pois, apresentou variação na concentração remanescente de até 80%, após processamento, estabelecendo áreas distintas dentro da câmara. No tratamento em autoclave, a GFPuv em solução apresentou resistência térmica em solução de fosfato pH 7,0 (valor F = 2,53 min (± 0,12)). Quando expressa por esporos de Bacillus subtilis, a intensidade de fluorescência emitida por esporos sobreviventes se manteve. A estabilidade térmica da GFPuv atestou sua potencialidade como indicador biológico fluorescente da garantia da eficácia de tratamento de soluções e materiais expostos ao calor.The recombinant Green Fluorescent Protein, GFPuv is an attractive system marker due to its ability to emit fluorescence when exposed to ultraviolet light, without use of substrates or complex environment. Being a stable molecule even in the presence of organic substances, temperatures above 70°C and wide range of pH, it is a potential Biological Indicator, BI, for many applications, including thermal processes. GFPuv thermal stability was evaluated by the loss of fluorescence intensity expressed in decimal reduction time (D-value, min), the exposure time required to reduce 90% of the GFPuv initial fluorescence intensity. GFPuv (3.5-9.0 µg/mL), expressed by E. coli and isolated by Three Phases Partitioning, TPP extraction with Hidrophobic Interaction Chromatography, HIC, was diluted in buffered solutions (each 10 mM: Tris-EDTA, pH 8; phosphate, pH 6 and 7, and acetate, pH 5) and in water for injection, WFI; pH = 6.70 (± 0.40), and exposed to temperatures of 25°C and between 80°C and 95°C. At 95°C, the D-value for GFPuv in 1.5%-50% glucose, ranged from: (i) 1.63 ± 0.23 min in acetate pH 5; (ii) 2.64 ± 0.26 min in WFI; (iii) 2.50 ± 0.18 min in phosphate, pH 6; (iv) 3.24 ± 0.28 min in phosphate, pH 7, (v) 2.89 ± 0.44 min in Tris-EDTA, pH 8. Sodium cloride provided a positive influence over GFPuv stability. In Tris-EDTA solutions, the addition of 15% and 20% of NaCl doubled the thermal stability of GFPuv (D = 65.79 min and D = 18.12 min at 80°C, and 85°C, respectively, in relation to the solutions without NaCl. For ethylene oxide sterilization processes (45°C-60°C), GFPuv can be used as biological indicator to monitor gas distribution into the chamber. After processing, the protein concentration varied by 80%, showing distinct areas into the chamber. In autoclave, GFPuv in solution showed thermal resistance in phosphate pH 7.0 solution (F-value = 2.53 (± 0.12) min. When expressed by Bacillus subtilis spores, the fluorescence intensity was kept constant after thermal processing. The thermal stability of GFPuv provides the basis for its potential utility as a fluorescent biological indicator to assess the efficacy of the treatment of liquids and materials exposed to steam.
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WU, YI-RU, and 吳宜儒. "Development of an Oxidation Indicator Using Schiff’s Reagent." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/g3wthw.
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碩士輔仁大學
食品科學系碩士班
107
Lipid is one of the major nutrients of food products. Lipid components, particularly unsaturated fatty acids, are ready to oxidize, where oxygen, water, light, heat and other detriments induce the lipid deterioration, resulting in degradation, then production of off-odors including aldehydes, alcohols, and acids. The objectives of this study were to develop an oxidation indicator based on the extent of aldehyde produced from lipid oxidation during the storage, and the use of sensing label to monitor lipid oxidation was with respect to color change corresponding to the quality of products. The Schiff’s reagent was compounded to detect aldehyde in indicator preparation, and phosphate buffer was used to replace hydrochloric acid in the Schiff’s reagent formula. Filter paper was then employed as the carrier of the indicator reagent to form label. Color development. measured using a colorimeter, on oxidation indicator, sensitivity, stability, and specificity tests were conducted, and then used in food application. Results showed that color of Schiff reagent changed from yellow to pink, and then purple when exposed to hexanal, and the rate of color change was found to be associated with the storage time and hexanal exposure. As Shiff’s reagent contacted to hexanal, ethanol, acetic acid, and ketones, only hexanal produced significant color change, but not other oxidized compounds, indicating the suitable specificity of sensing reagent. The ΔE value of the indicator label increased with relative humidity conditions, that color changed from pink to purple. As the relative humidity reached 53%, the ΔE value was determined to be 15.34±1.21, however, no further color change at higher RH%. Additionally, the color of label showed no significant difference (i.e. ΔE < 3) at high oxygen atmosphere, revealing a good stability in air. In the sensitivity test, the ΔE of indicator label increased with increasing amount of hexanal exposure, and the ΔE rised to 3.23±0.66 to 4.50±0.30. For food applications, residual oxygen content decreased in the package and the indicator label showed significant visual differnce, indicating that the indicator label effectively revealed oxidation status of packaged food product. Conclusively, oxidation indicator formulated using phosphatic Schiff’s reagent is beneficial to monitor hexanal concentration in headspace, thus is useful to indicate oxidation status of high fat content product during storage.
Books on the topic "Indicators and Reagents"
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American Chemical Society. Reagent chemicals: American Chemical Society specifications, official from January 1, 1987. 7th ed. Washington, DC: ACS, 1986.
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American Chemical Society. Reagent chemicals: Specifications and procedures : American Chemical Society specifications, official from January 1, 2006. Washington, DC: American Chemical Society, 2006.
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American Chemical Society. Reagent chemicals: American Chemical Society specifications, official from April 1, 1993. 8th ed. Washington, DC: The Society, 1993.
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Green, Floyd J. The Sigma-Aldrich handbook of stains, dyes, and indicators. Milwaukee, Wis: Aldrich Chemical Co., 1990.
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Sonntag, Oswald. Dry chemistry: Analysis with carrier-bound reagents. Amsterdam: Elsevier, 1993.
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G, Ellerd Michael, ed. Name reactions and reagents in organic synthesis. New York: Wiley, 1988.
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C, Morrill Terence, ed. Lanthanide shift reagents in stereochemical analysis. Deerfield Beach, FL: VCH, 1986.
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C, Morrill Terence, ed. Lanthanide shift reagents in stereochemical analysis. Germany: VCH Verlagsgesellschaft, 1987.
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National Institute of Allergy and Infectious Diseases (U.S.). Division of AIDS. AIDS Research and Reference Reagent Program catalog: Operated by ERC BioServices Corporation. Bethesda, Md: Division of AIDS, National Institutes of Allergy and Infectious Diseases, 1990.
Find full textBook chapters on the topic "Indicators and Reagents"
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"List of Reagents, Standards, pH Buffers, Acids, and Indicators, and Preparation of Standard Acids, Bases, and Buffers Required in the Instruction Guide." In Laboratory Guide for Conducting Soil Tests and Plant Analysis, 293–300. CRC Press, 2001. http://dx.doi.org/10.1201/9781420025293.axa.
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Abdulwahab Alfahad, Maadh. "The Activity of New Bio-Agent to Control Cucumovirus Cucumber Mosaic Virus (CMV)." In Studies on Cucumber (Cucumis sativus L.) [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96587.
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CMV virus is worldwide, especially in temperate regions, where it can infect more than 800 plant species belonging to about 40 families. Although the main factor that the plant takes in order not to be infected is because it has preventive means that inhibit the direction of pathogens so that the infection occurs under conditions that suit it and suit its success. Cucumber Mosaic Virus belongs to the group of plant viruses to the genus Cucumovirus, as the virus particles are symmetrically spherical, not enveloped, with a diameter of 29 nm, and the virus has several strains that differ among themselves in terms of factors, symptoms of infection and methods of transmission. The stimulation of induced systemic resistance (ISR) leads to the interest of many researchers. Many types of research and studies have been conducted in the field of biochemical changes in the form of modulating the host’s cell wall. The production of phytoalexin. And the manufacture of pathogen-related proteins (Pathogenesis Related Protein). It has been indicated that treatment with various factors, for example (non-pathogenic organisms, weak pathogens, chemical and industrial compounds, plant extracts, nutritional supplements) has the ability to activate plant defense mechanisms and induce systemic resistance against pathogens. In the field of biological control, bacterial types have been used on many pathogens, including fluorescens Pseudomonas and Bacillus subtillus, as they have proven effective in controlling many different fungal and bacterial pathogens as well as viral, and the reason is due to the ability of the bacteria to produce many growth regulators and thus stimulate resistance The systemic plant and the production of phytotoxins are in addition to being one of the most important growth stimuli. New methods have been used to resist viruses by using natural nutritional supplements with effective effect, because plants have defensive means, and for this reason, the use of these supplements can be stimulated in addition to the preventive aspect, a decrease in infection parameters, and an increase in growth indicators and outcome. Several methods have been relied upon to diagnose viruses, the first being the symptoms of reagents, and they are of basic methods. After that, serological tests were adopted, which are highly specialized and accurate in diagnosing viruses, and electron microscopy was used as a method to detect the size and shape of viruses. Polymerase Chain Reaction (PCR) technology is a fast and accurate way to detect plant viruses compared to other tests, such as the ELISA test and plant reagents.
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Mykhailova, Evgeniia. "ANALYSIS OF THE GREENHOUSE GAS EMISSIONS PROBLEM AND THE METHODS OF THEIR DISPOSAL." In The scientific paradigm in the context of technological development and social change. Publishing House “Baltija Publishing”, 2023. http://dx.doi.org/10.30525/978-9934-26-297-5-21.
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Global climate change is the most important environmental current problem. Its reason is the increase of greenhouse gas concentration in the atmosphere as a result of human activity. The climate change problem affects many aspects of the environment and society's existence, therefore, the development of tools and methods for reducing greenhouse gas emissions into the atmosphere is an actual task today. The purpose of the paper is a comprehensive analysis of the greenhouse gas emissions problem state in Ukraine and the world, and to determine the main ways to solve this problem. The scientific and research paper tasks are: to provide a general greenhouse gas characteristic, determine the main consequences of climate change for Ukraine, analyze Ukraine's international steps to solve the problem of global climate change, establish the structure of greenhouse gas emissions in Ukraine, analyze existing and propose optimal chemical and technological methods for greenhouse gases neutralizing. The methodology of the study is based on a monographic type of research using general research methods of analysis, synthesis, induction, deduction and historical detailing. The results. The article provides a general greenhouse gas characteristic, the main sources of their emissions and their consequences for humans and the environment. The steps taken by the world society and Ukraine, in particular, to solve the global climate change problem are analyzed. The problem is solved by concluding international agreements to stabilize the greenhouse gas concentration in the atmosphere at a level that does not have a dangerous anthropogenic impact on the climate of Earth. It was determined that the main sources of greenhouse gas emissions in Ukraine are the enterprises of the fuel and energy complex, and enterprises of the processing and mining industry. An analysis of chemical-technological cleaning methods for greenhouse gas is presented. Practical implications. The analytical review makes it possible to choose the optimal method of greenhouse gas neutralizing in industrial emissions. The method chosen will depend on the required degree of cleaning, composition and volume of gas, properties of reagents and auxiliary materials used possibilities of disposal of cleaning process products and technical and economic indicators of the chosen method. Value/originality. The conducted research allows for a comprehensive solution to the greenhouse gas emissions problem, understanding its causes, consequences, and social and chemical-technological solutions.
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Giannelli, Francesco, Peter M. Green,, and Susan J. Ramus. "Cleavage of mismatched bases using chemical reagents." In Mutation Detection, 81–98. Oxford University PressOxford, 1998. http://dx.doi.org/10.1093/oso/9780199636570.003.0006.
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Abstract Chemical cleavage of mismatch (CCM) was developed in 1988 as a method for screening cloned pieces of DNA for single base mismatches (1), but in combination with PCR was very soon used for the direct analysis of genomic DNA (2) and, later, for the analysis of mRNA (3). This technique detects mismatches in hybrid DNA. Heteroduplexes are formed by adding labelled normal DNA usually to an excess of unlabelled patient DNA. The heteroduplexes are reacted with either hydroxylamine which recognizes mismatched C bases or osmium tetroxide which recognizes mismatched T bases. Any mismatched or unmatched C or T bases are modified by the respective chemicals so that the modified strand can be cleaved with piperidine at the site of the mismatch. The products are analysed by electrophoresis on a denaturing polyacrylamide gel and the size of the fast running cleavage bands indicates the site of the mismatch. All manipulations involving the chemicals must be performed in a fume-hood.
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Hartmann, E., and T. A. Rapoport. "Signal sequence receptor (SSR) complex." In Secretory Pathway, 75. Oxford University PressOxford, 1994. http://dx.doi.org/10.1093/oso/9780198599425.003.0046.
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Abstract The $SR-complex has been purified from microsomal membranes of dog pancreas as a tetramer containing four polypeptides (SSRa, SSR . SSRy, SSRo) in stoichiometric relation (relative molecular mass 34 kDa, 22 kDa, 20 kDa, 18 kDa, respectively)1·3. Crosslinking with a bifunctional reagent indicates that the tetrameric complex exists in intact membranes. All subunits are integral membrane proteins12A- The a, . and 8-subunits span the membrane once with the (-termini located in the cytoplasm and the N-termini being translocated .
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de Franciscis, Vittorio, Günter Mayer, and Paloma H. Giangrande. "In Vitro Evolution and Aptamers." In Nucleic Acids in Chemistry and Biology, 403–20. The Royal Society of Chemistry, 2022. http://dx.doi.org/10.1039/9781837671328-00403.
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We present here the fundamentals of aptamer selection, beginning with the original in vitro systematic evolution of ligands by exponential enrichment (SELEX) protocol, first described in 1990, and culminating in recent advances in aptamer selection methodologies that have fast-tracked the development of aptamers for several research and therapeutic applications. These include advances in chemistries to impart stability and reduce toxicity, methodologies that have enabled the identification of aptamers to more complex targets and novel technologies such as next-generation sequencing (NGS), to fast-track the selection process and to provide a more complete in silico analysis of aptamer sequence families and their functional properties. We have highlighted applications of aptamers as research tools and as unique reagents for diagnostic and therapeutic applications. We have concluded this survey with an overview of those aptamers that have undergone clinical development and/or evaluation and have discussed the applications of this new class of chemically-modified oligonucleotides as potential diagnostics and therapeutics for a variety of clinical indications. We believe that aptamers constitute a research field with great potential for future advances.
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David, Serge. "Sugars in chiral synthesis." In The Molecular and Supramolecular Chemistry of Carbohydrates: Chemical Introduction to the Glycosciences, 128–42. Oxford University PressOxford, 1997. http://dx.doi.org/10.1093/oso/9780198500476.003.0008.
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Abstract The experiments we are about to describe bring into play chiral reagents constructed from a titanocene (titanium-carbohydrate complex) (Riediker and Duthaler 1989a; Duthaler et al. 1989; Bold et al. 1989; Riediker et al. 1989b). The starting compound is cyclopentadienyltitanium(IV) trichloride, C5H5TiCl3, which is prepared from dichloride (C5H5)iTiC12 by heating with TiC14. This trichloride reacts with 1,2:5,6-di-0-isopropylidene-α-D-glucofuranose (‘diacetone glucose’) in the presence of triethylamine to provide the bis-titanate 8.1. The latter is a crystalline compound, hence its structure could be determined in the solid state. Its form is that of a three-legged piano stool with the cyclopentadiene ring being its seat. The two ligands have completely different orientations with respect to the cyclopentadienyl ring. Because of this, they create a chiral cavity around the titanium atom. A study of the NMR spectra of 8.1 in solution indicates neither inversion at the metal centre nor rapid ligand exchange. This suggests that the conformation in solution is close to the conformation in the crystal.
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Spangenberg, Bernd. "Location of Separated Zones by Use of Visualization Reagents, UV Absorbance on Layers Containing a Fluorescent Indicator, and Densitometry." In Preparative Layer Chromatography, 163–75. CRC Press, 2006. http://dx.doi.org/10.1201/9781420005820.ch7.
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M. Jasim, Adnan, and Mohammed J. Jawad. "Pharmaceutical Applications of Vitamin E TPGS." In Vitamin E in Health and Disease - Interactions, Diseases and Health Aspects [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97474.
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D-tocopheryl polyethylene glycol succinate (Vitamin E TPGS) has been approved as a safe pharmaceutical adjuvant by FDA, and several drug delivery systems (DDS) based on TPGS have been developed. TPGS properties as a P-gp inhibitor, solubilizer/absorption and permeation enhancer in drug delivery and TPGS-related formulations such as nanocrystals, nanosuspensions, tablets/solid dispersions, vaccine system adjuvant, nutritional supplement, film plasticizer, anticancer reagent, and so on, are discussed in this review. Consequenly, TPGS can inhibit ATP-dependent P-glycoprotein activity and act as a potent excipient that promotes the efficiency of delivery and the therapeutic effect of drugs. Inhibition of P-gp occurs through mitochondria-dependent inhibition of the P-gp pump. Many of the latest studies address the use of TPGS for many poorly water-soluble or permeable drugs in the manufacture of nanodrugs or other formulations. In addition, it has been reported that TPGS shows a robust improvement in chylomicron secretion at low concentrations and improves intestinal lymphatic transport, which would also boost the potential of drug absorption. It also indicates that there are still many problems facing clinical translation of TPGS-based nanomedicines, requiring a more deep evaluation of TPGS properties and a future-based delivery method.
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Morowitz, Harold J. "The Litmus Test." In Entropy and the Magic Flute, 165–68. Oxford University PressNew York, NY, 1993. http://dx.doi.org/10.1093/oso/9780195081992.003.0036.
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Abstract IT’S DIFFICULT TO READ through a newspaper these days without encountering reference to a litmus test. Whether the article deals with appointing a Supreme Court justice or the director of the National Institutes of Health, the notion of such a test keeps working its way into the political rhetoric. To those of us who first encountered litmus in cherished childhood chemistry sets, the notion of a political litmus test impinges on the psyche in a strange way. Obviously, a more detailed understanding of litmus is called for. It begins, appropriately enough, with the 1911 edition of Encyclopaedia Britannica: LITMUS (apparently a corruption of lacmus, Dutch lacmoes, lac, lac, and moes, pulp, due to association with “lit,” an obsolete word for dye, colour; the Ger. equivalent is Lackmus, Fr. tournesol), a colouring matter which occurs in commerce in the form of small blue tablets, which, however, consist mostly, not of the pigment proper, but of calcium carbonate and sulphate and other matter devoid of tinctorial value. Litmus is extensively employed by chemists as an indicator for the detection of free acids and free alkalis. An aqueous infusion of litmus, when exactly neutralized by an acid, exhibits a violet colour, which by the least trace of free acid is changed to red, while free alkali turns it to blue. The reagent is generally used in the form of test paper bibulous paper dyed red, purple or blue by the respective kind of infusion. Litmus is manufactured in Holland from the same kinds of lichens (species Roccella and Lecanora) as are used for the preparation of archil.
Conference papers on the topic "Indicators and Reagents"
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Artemev, Alexandr, and Valentin Biryukov. "REDUCTION OF THE VOLUME OF PUMPING OF LIQUID WASTE FROM THE PRODUCTION OF APATITE CONCENTRATE DUE TO THE TECHNOLOGY OF PARTIALLY CLOSED WATER CIRCULATION." In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/51.
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"The use of recycled water supply technology in mineral dressing plants solves current environmental and economic problems for the mining and processing industry. Usually, water treatment takes a long time and requires constructing large-volume tailing dumps. The paper proposes a technology of a partially closed water circulation with the purification of watered production waste from suspended particles and water-soluble impurities that negatively affect the flotation process, based on the regularities describing the interaction of flocculants with the phases of a heterogeneous system of process waters. The authors have determined the most effective reagents providing optimal indicators of recycled water. The proposed technology is implemented in hardware in a radial thickener and eliminates the discharge of process water into an external tailings dumps facility, which will reduce the area occupied by production waste. Based on the particle size distribution data for various preliminary treatment options, differential and integral particle size distribution curves have been obtained. Analytical expressions of the obtained curves have been used to create discrete functions of volume fractions of particles with different sizes when constructing a model of the initial feed. The hydrodynamic processes of highly diluted suspension flows in the thickener’s body were studied using computational experiments on a model developed in the ANSYS Fluent software package, which is based on the real 3D geometry of a radial thickener. To build the geometry, the authors used a standard module GAMBIT. A computational experiment on cleaning the apatite concentrate discharge was performed on a virtual stand. The distributions of the concentrations of volume fractions of particles and the velocities of their movement in the thickener’s volume were obtained. The results of laboratory studies and computer simulation data allow the authors to tell about the prospect implementation of the technology of intra-plant water circulation, which will reduce by 10% the amount of wastewater discharged into the tailing dump. The use of the most efficient reagents will provide optimal water parameters for the content of suspended particles and hardness cations and, ultimately, will increase the technological and environmental performance of the Khibiny apatite-nepheline ores processing."
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Waiba, Prashant, Raj Bakhunchhe, Asim Maharjan, Rajin Pradhan, Sharad Timilsina, Rijan Maharjan, Thomas F. Krauss, and Ashim Dhakal. "RealtimeWAS: A Low-Cost, Portable Device for Real-time Detection of Fecal Contamination in Drinking Water." In Frontiers in Optics. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/fio.2023.fm5g.3.
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We present realtimeWAS: a low-cost, portable, and reagent-free device to detect fecal contamination in water using real-time fluorescence measurement. The device returns quantitative (via display) and semi-quantitative (via LED indicators) measures of water quality.
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Mahmoud, Mohamed, Ahmed Alsalman, and Hassan Almalki. "Novel Sample Pretreatment to Determine Iron Counts in Sour Glycol Streams by Spectrophotometer." In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21372-ms.
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Abstract Determination of Iron Content in Triethylene glycol (TEG) samples is a very important indicator in measuring the system corrosion rate in oil and gas facilities. This study employed the application of an alternative/easy and reliable test method, which involved the use of a spectrophotometer for quantification of Iron concentration in tri ethylene glycol samples, that are used in sour gas dehydration units, rather than the sophisticated technique of Inductively Coupled Plasma Optical Emission Spectroscopy, ICP-OES. The main challenge was how to eliminate/minimize the significant interference from the carryover condensate hydrocarbons, BTEX, H2S and amine additives, which cause either precipitation with spectrophotometer reagents or turbid samples. The sample pretreatment process included: 1 - Sample digestion with dilution to eliminate the dissolved acid gases and the dissolved BTEX from the sample in acidic medium; 2 - pH adjustment from 9 – 10.5 to eliminate the amine additives interference with spectrophotometer reagents and 3 – Application of standard addition technique with certified reference material for iron with dilution, to reach the spectrophotometer detection limit and give intense color with more UV absorbance. The method was validated against ICP-OES and the results variance were within 10% acceptance criteria.
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Toropovskiy, Andrey, Olga Pavlova, Denis Viktorov, Alexey Nikitin, and Olga Gulenko. "Testing of a Reagent Kit “TEST-NRAS-TISSUE” to Determine Indications for Targeted Therapy in Patients." In Conference on Health and Wellbeing in Modern Society (CHW 2021). Paris, France: Atlantis Press, 2022. http://dx.doi.org/10.2991/ahsr.k.220103.054.
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Bykov, Y. A., and E. S. Len. "ANALYSIS OF THE OPERATION OF WATER SUPPLY AND DRAINAGE SYSTEMS OF THE MEAT PROCESSING INDUSTRY ON THE EXAMPLE OF THE COMPANY «BORISOVSKY MEAT PROCESSING PLANT № 1»." In SAKHAROV READINGS 2021: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2021. http://dx.doi.org/10.46646/sakh-2021-2-158-162.
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The features of water supply and sanitation of meat processing industry enterprises are considered. The analysis of the functioning of local wastewater treatment facilities of JSC «Borisovsky Meat Processing Plant No. 1» has been carried out. The analysis of the functioning of the existing local wastewater treatment plants and the comparison of the efficiency of their functioning before the modernization showed that the efficiency of treatment increased and amounted to 75 to 95% according to the main indicators. The implemented method of reagent pressure flotation with the use of BAT allowed to bring the work of the local treatment facilities of the enterprise in compliance with the high requirements of the European Union.
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Peterson, C. B., C. M. Noyes, J. M. Pecon, F. C. Church, and M. N. Blackburn. "LYSINE-125 IS ESSENTIAL FOR HEPARIN BINDING TO ANTITHROMBIN." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643769.
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Identification of lysyl residue(s) in human plasma antithrombin required for binding of heparin was approached using chemical modification with the amino-group reagent, pyridoxal-5'-phosphate. Modification of antithrombin (AT) with limiting amounts of reagent yields an average incorporation of the phos-phopyridoxyl label into one lysine per protein molecule. Fractionation of the labeled AT by affinity chromatography on heparin-Sepharose separated a phosphopyridoxylated AT species devoid of heparin binding (Pool I) from modified protein which retained affinity for heparin (Pool II). Pool I contained an average of 1.6 mol phosphopyridoxyl label per mol AT, whereas Pool II was labeled to a lesser extent, with a ratio of 1.0 mol phosphopyridoxyl per mol protein. To generate peptide maps of the two AT species, the proteins were reductively denatured, S-carboxymethylated, and digested with trypsin. Fractionation of the tryptic digests by reverse-phase HPLC indicated one peak in the chromatogram of the non-heparin-binding species to be clearly different when compared to the chromatogram of the heparin-binding species. Upon sequencing of the unique peptide by automated Edman degradation, the modified residue was identified as Lys-125 in the primary sequence of AT. Additionally, AT was reacted with pyridoxal-5 ′-phosphate in the presence of added heparin for comparison with protein modified in the absence of heparin. Overall incorporation of the phosphopyridoxyl label was 3-4 mol reagent per mol protein, without inclusion of heparin during the modification reaction, and only 2-3 mol pyridoxyl per mol protein with heparin added. Tryptic peptide maps of these two modified ATs indicated that eight lysine residues are "protected" from modification by addition of heparin. The "protected" lysines identified, in addition to the essential Lys-125, are residues 11, 39, 133, 136, 257, 275, and 287. Identification of Lys-125 as the critical lysine for heparin binding strongly supports previous data which indicates that the heparin-binding domain of AT is located at the N-termi-nus within one of the disulfide cross-linked loops of the protein.
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Zhang, Dan, and Jinping Suo. "Preparation of Al2O3 Coated SiC Powders by Heterogeneous Precipitation." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29747.
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Alumina has been identified as a most promising material in tritium permeation barrier. By introducing some additive into the alumina improves its effectiveness. The purpose of this study was to synthesize Al2O3 coated SiC particles by heterogeneous precipitation method to replace the pure alumina as the raw material of coating. A series of factors which influenced the properties of coated powders had been studied, including the concentration of Al(NO3)3 solution, surface active reagent, the addition amount of SiC, calcinations temperature etc. The coated powders were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Zeta-potential analyzer. The result indicates that the addition of certain amount of nano powers can reduce the phase transformation temperature of the alpha alumina. α-Al2O3 coated SiC powders were obtained by calcining Al(OH)3/SiC precursor at 1100 degree centigrade.
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Meinzer, R. A., and H. H. Michels. "Chemically produced metastable magnesium atoms for laser pumping." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.wb4.
Full textAbstract:
A chemical reaction has been used to chemically produce metastable magnesium atoms by sequentially reacting ground state magnesium atoms with N2O and CO. Formation of the excited atoms occurs via a Mg–N2O complex which is reduced by reaction with CO to form metastable magnesium atoms. In these experiments, the metastable magnesium atoms were produced in a supersonic flow; the success of this investigation demonstrated the feasibility of scaling Benard’s subsonic flow experiments. Analysis of our data indicates that the observed excited magnesium atom concentration can be increased over measured levels by an order of magnitude. This prediction is based in part on calculations which were made using the experimentally measured rate constant data for the Mg–N2O reaction. With the predicted increase in the Mg[3P] concentration, chemically pumped metastable magnesium atoms should be an excellent energy storage medium for an energy transfer visible chemical laser. Mg[3P] atoms have a relatively long radiative lifetime, 4.5 ms; deactivation of Mg[3P] by various reagents is slow; spontaneous emission from the metastable electronic energy level to the ground state is in the blue region, 3P−1S:457.1 nm; and the metastable magnesium atoms can be chemically pumped. Some of the potential energy transfer candidates are evaluated and are discussed in detail in some of the related presentations.
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Aberle, Cedric, Mark Lewis, Gan Yu, Nan Lei, and Jie Xu. "Evaporation of Liquid Marbles on a Heated Surface: Coating-Assisted Leidenfrost Phenomenon." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65015.
Full textAbstract:
The Leidenfrost effect is a well-known heat transfer phenomenon, which predicts that liquid droplets will show prolonged evaporation time when they are placed on a hot surface with a temperature higher than a critical value. This effect is due to film boiling, where a vapor film helps insulate the drop from the hot surface. In this paper, we show that specially engineered droplets — liquid marbles — can exhibit Leifenfrost effect at any temperature above the boiling point without experiencing any transition. Liquid marbles are spheres with a liquid core that are coated with hydrophobic particles. When brought into contact with a solid surface, liquid marbles are completely nonwetting due to the fact that the hydrophobic powder is in between the liquid and solid surface. Liquid marbles may be used as excellent microreservoirs for biosample handling and chemical reagent manipulation. In our study, liquid marbles are synthesized by coating water droplets with graphite particles. We investigate the thermal evaporation of the fabricated graphite liquid marbles on a hot substrate at prescribed temperatures, and compare the results with pure water droplets. The evaporation time of both liquid marbles and water droplets are recorded at various temperatures. If the temperature is above the Leidenfrost point, the evaporation of both liquid marbles and water droplets are prolonged with similar amount of time (about 100s), which indicates that similar physics might at play in both cases: heat transfer is impeded by a thin layer of vapor. If the temperature is below the Leidenfrost point, water droplets evaporate a hundred times faster. This is because the vapor film cannot self-sustain and levitate the droplet anymore. On the other hand, liquid marbles still evaporate slowly with the same level of time as Leidenfrost evaporation times, which indicates that the Leidenfrost effect still takes effect for liquid marbles even below the critical temperature. This might be due to the fact that the coating of the liquid marble helps levitate the liquid core, maintaining a layer of insulating vapor. In the end, we report detailed deformation of liquid marbles during evaporation. This coating-assisted Leidenfrost phenomenon could be useful in many applications where film boiling is desired. The strong thermal robustness of graphite liquid marbles over a wide temperature range, together with the inert reactivity, electrical conductivity and superior lubrication properties of graphite, make graphite liquid marbles potentially useful in a wealth of applications in microfluidics and lab on a chip devices.
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Koneti Rao, A., and Maria A. Kowalska. "ADP-INDUCED CYTOPLASMIC CALCIUM MOBILIZATION AND SHAPE CHANGE IN PLATELETS ARE MEDIATED BY DIFFERENT BINDING SITES." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644466.
Full textAbstract:
Platelet stimulation with ADP results in a number of responses including increase in cytoplasmic ionized calcium concentration [Ca2+]i, shape change, aggregation, secretion, and inhibition of cAMP accumulation caused by PGI2.5'-Fluorosulphonylbenzoyladenosine (FSBA), which covalently labels ADP binding site on platelets, blocks platelet shape change but not inhibition of cyclic AMP levels by ADP, while p-chloromercuribenzenesulfonate (pCMBS), a non-penetrating thiol reagent, blocks ADP-induced inhibition of adenylate cyclase but not shape change. We examined the effect of FSBA and pCMBS on ADP-induced increase in [Ca2+]i to determine whether it is linked to the binding site mediating shape change or that for inhibition of adenylate cyclase. In platelets loaded with Ca2+ indicators, quin 2 or fura 2, and in presence of adenosine deaminase (AD), FSBA (50-200 μM) induced a dose-dependent, rapid rise in [Ca2+]i. from basal levels of 70-90 nM to peak levels of 300-500 nM in the presence of 1 mM external Ca2+ providing direct evidence that FSBA is a platelet agonist. The [Ca2+ ]i. returned to near basal levels over 30 min. The effect of FSBA on [Ca2+]i. was inhibited by ZK 36,374 (40 nM), a stable PGI2 analog. AdP concentrations eliciting similar responses were about 10-fold less than those for FSBA. Platelet incubation with FSBA (50-100 μM) in the presence of AD for 30 min (to ensure optimal covalent labelling of the ADP binding sites) abolished shape change but jjid not inhibit ADP (5, 25 μM)-induced increase in [Ca2+]i. or block the inhibitory effect of ADP on cAMP accumulation in1platelets exposed to ZK 36,374 (50 nM) in.presence of theophylline (7 mM). Incubation with pCMBS (5-100 pM, 2 min) abolished the effect of ADP on [Ca2+]. and on the inhibition of cAMP levels; shape change was not 1 inhabited even at 1 mM. pCMBS (0.5-1 mM) inhibited the rise in [Ca2+ ]. by FSBA alone. These observations suggest that ADP-induced Ca mobilization is mediated by platelet binding sites which are distinct from those mediating shape change but probably the same as those modulating adenylate cyclase.