KINETIC SULFUR ISOTOPE EFFECTS IN AROMATIC BROMODESULFONATION

1966 ◽  
Vol 44 (3) ◽  
pp. 363-378 ◽  
Author(s):  
B. T. Baliga ◽  
A. N. Bourns
Keyword(s):  
Sulfur Isotope ◽  
Isotope Effects ◽  
Ion Concentration ◽  
Step Process ◽  
Bromide Ion ◽  
Alternate Mechanism ◽  
One Step ◽  
The Individual ◽  
Step Mechanism

Both bromodeprotonation and bromodesulfonation occur during aqueous bromination of sodium p-methoxybenzenesulfonate, A, and potassium 1-methylnaphthalene-4-sulfonate, B. Whereas for A the bromodeprotonation increases appreciably in amount as the bromide ion concentration is raised, this reaction takes place to a relatively small extent for the less reactive B. A reinvestigation of the kinetics of bromination and a determination of sulfate yields for both of these compounds over a range of bromide ion concentration of 0 to 0.5 M have been made to evaluate the individual rates of these two competing reactions. The kinetic data for the bromodesulfonation of A favor a two-step mechanism with Br2 as the brominating species, but are not considered to eliminate completely a one- or two-step process involving Br+ (or H2OBr+). For B, the kinetics allow either a one- or two-step mechanism with molecular bromine as the brominating agent.Kinetic sulfur isotope effects (k32/k34) have been measured for the bromodesulfonation of A at different bromide ion concentrations. The observed effects are: at [Br−] = 0, 0.3%; at [Br−] = 0.03 M, 1.3%; at [Br−] = 0.5 M, 1.7%. These results confirm the two-step mechanism favored by kinetics and allow the rejection of the alternate mechanism with Br+ (or H2OBr+) as the brominating species. A similar study of B gave the following results: at [Br−] = 0, 0.2%; at [Br−] = 0.25 M, 0.3%; at [Br−] = 0.5 M, 0.4%; at [Br−] = 2.0 M, 0.8%. These results establish the two-step mechanism for this compound and completely eliminate the alternate one-step process.

scholarly journals KINETIC HYDROGEN ISOTOPE EFFECTS IN AROMATIC BROMODEPROTONATION

1966 ◽  
Vol 44 (3) ◽  
pp. 379-386 ◽  
Author(s):  
B. T. Baliga ◽  
A. N. Bourns
Keyword(s):  
Isotope Effect ◽  
Hydrogen Isotope ◽  
Salt Effect ◽  
Isotope Effects ◽  
Effect Study ◽  
Ion Concentration ◽  
Bromide Ion ◽  
Halogenation Reaction ◽  
Hydrogen Isotope Effect ◽  
Step Mechanism

The bromodeprotonation of sodium p-methoxybenzenesulfonate is an ordinary halogenation reaction in which a hydrogen ortho to the methoxy group is replaced by bromine. The kinetic data for this reaction do not distinguish between a one- and a two-step mechanism with Br2 as the brominating species. The two-step mechanism was confirmed by the observation of a variation in the kinetic hydrogen isotope effect, kH/kD, with changing bromide ion concentration. The observed isotope effects are 1.01, 1.07, 1.18, and 1.31 at bromide ion concentrations 0, 0.5, 1, and 2 M, respectively.The isotope effect study strongly establishes that in this reaction the small depression in rate produced by bromide ion, beyond that due to Br3− formation, arises mainly from a salt effect, and only a small amount of this depression is caused by return of the intermediate to reactants.

Analysis of Bromide Ion in Wine by Ion Selective Electrode

1976 ◽  
Vol 59 (1) ◽  
pp. 53-55
Author(s):  
James E Graf ◽  
Troy E Vaughn ◽  
William H Kipp
Keyword(s):  
Country Of Origin ◽  
Ion Selective Electrode ◽  
Ion Concentration ◽  
Selective Electrode ◽  
Bromide Ion

Abstract The use of the bromide ion selective electrode for the determination of bromide ion in wine has been found to be rapid and reliable. The method has been used for still wines and carbonated wines and is applicable to all wines regardless of their country of origin. The method consists of treating a 50 ml aliquot of wine with 2 ml each of 3.75M H3PO4, saturated KNO3, and 1M CuSO4. After 10 min the electrodes are immersed in the samples and a millivolt reading is obtained. One hundred μl 500 ppm bromide ion standard is added and the millivolt reading is taken. Bromide ion concentration in the wine = (CΔ × 1)/((antilog ΔE/S) − 1) where CΔ = 1, ΔE = the change in potential expressed in millivolts, and S = the electrode slope.

scholarly journals Determination of Bromide Ion Concentration in Urine Using a Head-space Gas Chromatography and an Ion Chromatography

1991 ◽  
Vol 13 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Minoru KOGA ◽  
Kyoko HARA ◽  
Hajime HORI ◽  
Yasushi KODAMA ◽  
Toshiteru OKUBO
Keyword(s):  
Gas Chromatography ◽  
Ion Chromatography ◽  
Ion Concentration ◽  
Head Space ◽  
Bromide Ion ◽  
Head Space Gas Chromatography

scholarly journals Precise determination of equilibrium sulfur isotope effects during volatilization and deprotonation of dissolved H2S

2019 ◽  
Vol 248 ◽  
pp. 242-251 ◽  
Author(s):  
Min Sub Sim ◽  
Alex L. Sessions ◽  
Victoria J. Orphan ◽  
Jess F. Adkins
Keyword(s):  
Sulfur Isotope ◽  
Isotope Effects ◽  
Precise Determination

ПСИХОЛОГІЧНА ДЕТЕРМІНАЦІЯ ДОМІНУЮЧОГО ІНСТИНКТУ У КОНСТРУКТИВНІЙ САМОРЕАЛІЗАЦІЇ ЖІНОК

1970 ◽  
Vol 6 (1) ◽  
pp. 184-193
Author(s):  
Ольга Віговська
Keyword(s):  
Human Life ◽  
Healthy Children ◽  
Self Disclosure ◽  
Self Identity ◽  
Social Nature ◽  
Self Actualization ◽  
Rational Organization ◽  
The Individual ◽  
Age Range

У статті теоретично обґрунтовано феномен конструктивного самозбереження особистості як ознаки самоактуалізації, розкриття власного потенціалу і побудови перспективи розвитку особистості та емпірично виявлено ознаки психологічної детермінації домінуючого інстинкту у конструктивній самореалізації жінок з різним соціальним статусом. Зазначено, що проблема самозбереження асоціюється з особливостями прояву інстинкту самозбереження людини, але потреби вищого порядку зумовлюють соціальну природу її поведінки, яка локалізована у найвищій точці самореалізації. Теоретично обгрунтовано, що самореалізація визначає тенденцію раціональної організації життя людини та проявляється у її почутті задоволеністю життям. З’ясовано, що психологічну основу конструктивного самозбереження становлять індивідуально-типологічні характеристики людини, які відображають психофізіологічні та психосоціальні резерви самореалізації особистості. Розроблена програма емпіричного дослідження, а також комплекс використаних методів математичної обробки результатів дослідження дає змогу конкретизувати психологічний зміст детермінації домінуючого інстинкту у конструктивній самореалізації жінок вікового діапазону 35-45 років та з різним соціальним статусом. У жінок, які виховують проблемну (хвору) дитину, домінує інстинкт "егофільного типу", що виражається у їх надмірному егоцентризмі і супроводжується низькими показниками самоактуалізації, на відміну від досліджуваних жінок, які виховують здорових дітей і у яких на фоні вираженої тенденції до самоактуалізації домінує базовий інстинкт "дослідницького типу" та "лібертофільного типу". This article theoretically proves constructive phenomenon of self identity as signs of self-disclosure own potential and prospects of development of individual construction. In addition, it empirically showes signs of psychological determination of the dominant instinct in a constructive self-determination of women with different social statuses. It was noted that the issue of self-preservation is associated with the peculiarities of manifestation of self-preservation instinct of man, but it needs higher-order cause social nature of the behavior that is localized at the highest point of self-realization. It theorized that self-realization determines the trend of rational organization of human life and manifests itself in its sense of life satisfaction. It was found that the psychological basis of constructive self-preservation of the individual make individually-typological characteristics of a person that reflect physiological and psychosocial reserves of self-realization. The developed program of empirical research, as well as the methods used complex mathematical processing of results of research allows to specify the content of the psychological determination of the dominant instinct of constructive self-realization а women age range of 35-45 years and with different social status. Women who bring up the problem child dominates the instinct of self-preservation, which is reflected in their excessive self-centeredness, and is accompanied by low levels of self-actualization, as opposed to the study of women who are raising healthy children and that against the backdrop of a pronounced tendency to self-actualization, dominated by basic instinct "research type" and "independent type."

Fluctuations of Annual Precipitation and Water Resources Quality in Ukraine

2016 ◽  
Vol 10 (4s) ◽  
pp. 621-629
Author(s):  
Valentina Pidlisnyuk ◽  
◽  
John Harrington JR ◽  
Yulia Melnyk ◽  
Yuliya Vystavna ◽  
...  
Keyword(s):  
Water Resources ◽  
Surface Waters ◽  
Precipitation Amount ◽  
Ion Concentration ◽  
Annual Precipitation ◽  
Resource Quality ◽  
Phosphate Ion ◽  
Regional Trends

The article focuses on examining the influence of fluctuations in annual precipitation amount on the quality of surface waters. Water quality was estimated with data on BOD, COD and phosphate–ion concentration within five selected regions of Ukraine. Analysis of the precipitation data (1991 – 2010) showed different regional trends. Using the statistics, determination of the interconnection between precipitation amount and water resources quality were done. The obtained regularities and associated uncertainties can be used for prediction of changes in water resource quality and as a guide for future adaptation to possible climate change.

Determination of allostatic load dynamics in the assessment of adaptation in temporary workers in the Arctic

2020 ◽  
pp. 547-548
Author(s):  
O. Yu. Atkov ◽  
S. G. Gorokhova
Keyword(s):  
Body Mass Index ◽  
Glucose Level ◽  
Shift Work ◽  
Allostatic Load ◽  
The Arctic ◽  
Temporary Workers ◽  
Short Term ◽  
Short Term Adaptation ◽  
The Individual

The individual dynamics of the allostatic load index was revealed mainly due to changes in the glucose level, body mass index, which makes it applicable for assessing the short-term adaptation to the stay in the conditions of shift work

THE SUBJECT FIELD OF INSTITUTIONAL EDUCATION: THE SENSE AND PROSPECTS OF DEVELOPMENT IN UKRAINE

2020 ◽  
pp. 25-38
Author(s):  
Irina Mordous
Keyword(s):  
Decisive Role ◽  
Subject Field ◽  
National Education ◽  
Progressive Development ◽  
Separate Area ◽  
Economic Transformations ◽  
The Difference ◽  
The Individual ◽  
Political Economic

The development of modern civilization attests to its decisive role in the progressive development of institutions. They identified the difference between Western civilization and the rest of the world. Confirmation of the institutional advantages of the West was its early industrialization. The genesis and formation of institutionalism in its ideological and conceptualmethodological orientation occurs as a process alternative to neoclassic in the context of world heterodoxia, which quickly spread in social science. Highlighting institutional education as a separate area of sociocultural activity is determined by the factor of differentiation of institutional theory as a whole. A feature of institutional education is its orientation toward the individual and his/her transformation into a personality. The content of institutional education is revealed through the analysis of the institution, which includes a set of established customs, traditions, ways of thinking, behavioral stereotypes of individuals and social groups. The dynamics of socio-political, economic transformations in Ukraine requires a review of the foundations of national education and determination of the prospects for its development in the 21st century in the context of institutionalism.

Development and Validation of an LC-MS/MS Method for Simultaneous Determination of Canagliflozin and Metformin HCl in Rat Plasma and its Application

2020 ◽  
Vol 16 (6) ◽  
pp. 752-762
Author(s):  
Vivek Nalawade ◽  
Vaibhav A. Dixit ◽  
Amisha Vora ◽  
Himashu Zade
Keyword(s):  
Internal Standard ◽  
Rat Plasma ◽  
Precipitation Method ◽  
Herbal Extracts ◽  
One Step ◽  
Precision And Accuracy ◽  
Development And Validation ◽  
The Impact ◽  
Metformin Hcl

Background: Food and herbal extracts rich in Quercetin (QRT) are often self-medicated by diabetics and can potentially alter the pharmacokinetics (PK) of Metformin HCl (MET) and Canagliflozin (CNG) leading to food or herb-drug interactions and reduced therapeutic efficacy. However, the impact of these flavonoids on the pharmacokinetic behaviour of MET and CNG is mostly unknown. Methods: A simple one-step protein precipitation method was developed for the determination of MET and CNG from rat plasma. The mobile phase chosen was MeOH 65% and 35% water containing 0.1% formic acid at a flow rate of 1mL/min. Results: The retention time of MET, internal standard (Valsartan) and CNG was 1.83, 6.2 and 8.2 min, respectively. The method was found to be linear in the range of 200 - 8000 ng/mL for CNG and 100 = 4000 ng/ml for MET. Precision and accuracy of the method were below 20% at LLOQ and below 15% for LQC, MQC, and HQC. Conclusion: The method was successfully applied for the determination of PK of MET and CNG by using 100 μL of rat plasma. QRT co-administration affects the PK parameters of MET and CNG. This alteration in PK parameters might be of significant use for clinicians and patients.

scholarly journals The Concept of Accuracy Analysis of the Vertical Displacements Gained from the Hydrostatic Levelling Systems’ Measurements

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4842
Author(s):  
Waldemar Kamiński
Keyword(s):  
Accuracy Assessment ◽  
Theoretical Models ◽  
Vertical Displacement ◽  
Serial Connection ◽  
Vertical Displacements ◽  
Comprehensive Determination ◽  
The One ◽  
The Individual ◽  
Reference Sensor

Nowadays, hydrostatic levelling is a widely used method for the vertical displacements’ determinations of objects such as bridges, viaducts, wharfs, tunnels, high buildings, historical buildings, special engineering objects (e.g., synchrotron), sports and entertainment halls. The measurements’ sensors implemented in the hydrostatic levelling systems (HLSs) consist of the reference sensor (RS) and sensors located on the controlled points (CPs). The reference sensor is the one that is placed at the point that (in theoretical assumptions) is not a subject to vertical displacements and the displacements of controlled points are determined according to its height. The hydrostatic levelling rule comes from the Bernoulli’s law. While using the Bernoulli’s principle in hydrostatic levelling, the following components have to be taken into account: atmospheric pressure, force of gravity, density of liquid used in sensors places at CPs. The parameters mentioned above are determined with some mean errors that influence on the accuracy assessment of vertical displacements. In the subject’s literature, there are some works describing the individual accuracy analyses of the components mentioned above. In this paper, the author proposes the concept of comprehensive determination of mean error of vertical displacement (of each CPs), calculated from the mean errors’ values of components dedicated for specific HLS. The formulas of covariances’ matrix were derived and they enable to make the accuracy assessment of the calculations’ results. The author also presented the subject of modelling of vertical displacements’ gained values. The dependences, enabling to conduct the statistic tests of received model’s parameters, were implemented. The conducted tests make it possible to verify the correctness of used theoretical models of the examined object treated as the rigid body. The practical analyses were conducted for two simulated variants of sensors’ connections in HLS. Variant no. I is the sensors’ serial connection. Variant no. II relies on the connection of each CPs with the reference sensor. The calculations’ results show that more detailed value estimations of the vertical displacements can be obtained using variant no. II.

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