Reactivity Optimization of Prevulcanization Inhibitors

1983 ◽  
Vol 56 (5) ◽  
pp. 1061-1079 ◽  
Author(s):  
A. B. Sullivan ◽  
L. H. Davis ◽  
O. W. Maender
Keyword(s):  
Side Reactions ◽  
Inhibitor Activity ◽  
Proper Selection ◽  
Leaving Group ◽  
Leaving Groups ◽  
The Relationship ◽  
Selection Of

Abstract A series of phthalimide-based prevulcanization inhibitors has been used to probe the relationship between MBT reactivity and inhibitor performance efficiency in NR accelerated with TBBS. Based on these results, there appears to be a reactivity window for best performance. For the phthalimide series, it occurs with secondary alkyl mercaptans. Inhibitors with MBT reactivity below the optimum are less effective because they do not compete with the accelerator for the autocatalyst. The activity also falls off at higher reactivities. There are two explanations for this behavior. First, as proposed by others, the very reactive inhibitors may not completely survive mixing and precuring, so that some of the inhibitor is lost to unproductive side reactions. Over and above this effect, the performance declines because the MBT is trapped less securely when the BtSSR is derived from a more reactive mercaptan. Although other leaving groups were not evaluated in this work, it is clear that reactivity optimization can be achieved with any leaving group, L, by proper selection of -SR. For example, in the work of Morita and Sullivan with thioketal type prevulcanization inhibitors, it was demonstrated that primary alkyl and aromatic mercaptans were required to achieve optimum inhibitor activity.

Microemulsion Performance Fluids

1989 ◽  
Vol 177 ◽  
Author(s):  
J. Bock ◽  
M. L. Robbins ◽  
S. J. Pace
Keyword(s):  
Phase Behavior ◽  
Single Phase ◽  
Interfacial Area ◽  
Immiscible Fluids ◽  
Proper Selection ◽  
Solubilization Capacity ◽  
Low Interfacial Tension ◽  
Multi Phase ◽  
The Relationship ◽  
Selection Of

ABSTRACTMicroemulsions are thermodynamically stable mixtures of two immiscible fluids, such as oil and water, and one or more surfactants or cosurfactants. These systems have a rich micro-structure and phase behavior which can take the form of a variety of multi-phase and single phase oil- or watercontinuous or bicontinuous fluids with unique and useful properties. The thermodynamic stability, ultra-low interfacial tension, clarity, high solubilization capacity and high interfacial area suggest uses “performance fluids.” The relationship between surfactant ussetsru cfotur reth eansde the phase behavior and properties of microemulsions is the key to their design. Through the proper selection of surfactants, microemulsion phase continuity can be tailored for a variety of applications. Two such applications, coal freeze conditioning and oil spill dispersion, are described in this paper.

Meriel Talbot and the Society for the Overseas Settlement of British Women, 1919–1937

2017 ◽  
Vol 10 (1) ◽  
pp. 32-52
Author(s):  
Bonnie White
Keyword(s):  
Domestic Service ◽  
Agricultural Workers ◽  
British Government ◽  
Early Failure ◽  
Proper Selection ◽  
Domestic Servants ◽  
Female Workers ◽  
Female Migrants ◽  
Post War ◽  
Selection Of

In 1917 the British government began making plans for post-war adjustments to the economy, which included the migration of surplus women to the dominions. The Society for the Overseas Settlement of British Women was established in 1920 to facilitate the migration of female workers to the dominions. Earlier studies have argued that overseas emigration efforts purposefully directed women into domestic service as surplus commodities, thus alleviating the female ‘surplus’ and easing economic hardships of the post-war period. This article argues that as Publicity Officer for the SOSBW, Meriel Talbot targeted women she believed would be ideal candidates for emigration, including former members of the Women's Land Army and affiliated groups. With the proper selection of female migrants, Talbot sought to expand work opportunities for women in the dominions beyond domestic service, while reducing the female surplus at home and servicing the connection between state and empire. Dominion authorities, whose demands for migrant labour vacillated between agricultural workers during the war years and domestic servants after 1920, disapproved of Talbot's efforts to migrate women for work in agriculture. Divergent policies led to the early failure of the SOSBW in 1923.

IMPROVEMENT OF SPRING DURUM WHEAT SELECTION METHODOLOGIES UNDER CLIMATE CHANGE CONDITIONS

1970 ◽  
pp. 33-36
Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko
Keyword(s):  
Grain Yield ◽  
Durum Wheat ◽  
Correlation Coefficient ◽  
Harvest Index ◽  
Unit Area ◽  
Correlation Coefficients ◽  
Chemical Mutagenesis ◽  
Main Method ◽  
The Relationship ◽  
Selection Of

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.

Analisa Pemilihan Moda Transportasi Umum Rute Tanjung Karang – Bandara Radin Inten II Dengan Stated Preference dan Uji Crame’s V

2018 ◽  
Vol 2 (2) ◽  
pp. 137
Author(s):  
Muhammad Abi Berkah Nadi
Keyword(s):  
Regression Analysis ◽  
Utility Function ◽  
Stated Preference ◽  
Technical Analysis ◽  
Chi Square ◽  
Time Headway ◽  
Independent Variable ◽  
The Relationship ◽  
Selection Of

Radin Inten II Airport is a national flight in Lampung Province. In this study using the technical analysis stated preference which is the approach by conveying the choice statement in the form of hypotheses to be assessed by the respondent. By using these techniques the researcher can fully control the hypothesized factors. To determine utility function for model forecasting in fulfilling request of traveler is used regression analysis with SPSS program. The analysis results obtained that the passengers of the dominant airport in the selection of modes of cost attributes than on other attributes. From the result of regression analysis, the influence of independent variable to the highest dependent variable is when the five attributes are used together with the R square value of 8.8%. The relationship between cost, time, headway, time acces and service with the selection of modes, the provision that states whether or not there is a decision. The significance of α = 0.05 with chi-square. And the result of Crame's V test average of 0.298 is around the middle, then the relationship is moderate enough.

A Biomarker Combining Imaging and Neuropsychological Assessment for Tracking Early Alzheimer's Disease in Clinical Trials

2018 ◽  
Vol 15 (5) ◽  
pp. 429-442 ◽  
Author(s):  
Nishant Verma ◽  
S. Natasha Beretvas ◽  
Belen Pascual ◽  
Joseph C. Masdeu ◽  
Mia K. Markey ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Trials ◽  
Cognitive Impairment ◽  
Latent Variable ◽  
Brain Regions ◽  
Disease Assessment ◽  
Latent Variable Analysis ◽  
The Relationship ◽  
Selection Of

Background: Combining optimized cognitive (Alzheimer's Disease Assessment Scale- Cognitive subscale, ADAS-Cog) and atrophy markers of Alzheimer's disease for tracking progression in clinical trials may provide greater sensitivity than currently used methods, which have yielded negative results in multiple recent trials. Furthermore, it is critical to clarify the relationship among the subcomponents yielded by cognitive and imaging testing, to address the symptomatic and anatomical variability of Alzheimer's disease. Method: Using latent variable analysis, we thoroughly investigated the relationship between cognitive impairment, as assessed on the ADAS-Cog, and cerebral atrophy. A biomarker was developed for Alzheimer's clinical trials that combines cognitive and atrophy markers. Results: Atrophy within specific brain regions was found to be closely related with impairment in cognitive domains of memory, language, and praxis. The proposed biomarker showed significantly better sensitivity in tracking progression of cognitive impairment than the ADAS-Cog in simulated trials and a real world problem. The biomarker also improved the selection of MCI patients (78.8±4.9% specificity at 80% sensitivity) that will evolve to Alzheimer's disease for clinical trials. Conclusion: The proposed biomarker provides a boost to the efficacy of clinical trials focused in the mild cognitive impairment (MCI) stage by significantly improving the sensitivity to detect treatment effects and improving the selection of MCI patients that will evolve to Alzheimer’s disease.

Excessive Belching: a Separate Syndrome or Another Symptom of Functional Dyspepsia?

2020 ◽  
Vol 30 (3) ◽  
pp. 55-60 ◽  
Author(s):  
A. A. Sheptulin ◽  
O. A. Storonova
Keyword(s):  
Functional Dyspepsia ◽  
Functional Gastrointestinal Disorders ◽  
High Resolution Manometry ◽  
Published Evidence ◽  
Key Points ◽  
Dyspeptic Symptoms ◽  
The Relationship ◽  
Rome Iv ◽  
Selection Of ◽  
Optimal Treatment Strategy

Aim of review. Interpretation of published evidence on the relationship between the excessive belching syndrome and functional dyspepsia (FD) and their management in patient care.Key points. According to the Rome IV criteria of functional gastrointestinal disorders (FGID), excessive belching in the absence of other dyspeptic symptoms is to be considered a manifestation of the excessive belching syndrome, which can be of gastric or supragastric nature. Combination of high-resolution manometry and impedancemetry allows an accurate diagnosis of belching and selection of optimal treatment strategy. Belching complicated by other symptoms of dyspepsia is to be considered yet another FD symptom according to the Rome IV criteria of FGID. Prokinetics are recommended to relieve belching in such cases.Conclusion. Understanding the relationship between the excessive belching syndrome and FD requires further research.

The effect of steric size of leaving group on rates of the competing syn- and anti-pathways in biomolecular elimination

1980 ◽  
Vol 45 (8) ◽  
pp. 2171-2178
Author(s):  
Jiří Závada ◽  
Magdalena Pánková
Keyword(s):  
Comparative Analysis ◽  
Homologous Series ◽  
Leaving Group ◽  
Leaving Groups

Approximate rates of the competing syn- and anti-pathways have been determined in t-C4H9OK-t-C4H9OH promoted elimination from two homologous series of tosylates: I-OTs trans-III (R = H, CH3, C2H5, n-C3H7, i-C3H7, t-C4H9) and II-OTs trans-IV (R = CH3, C2H5, n-C3H7, i-C3H7, t-C4H9). A comparison has been made with rates of the same processes in the (+) elimination of the corresponding trimethylammonium salts I-N(CH3)3 trans-III and (+) II-N(CH3)3 trans-IV. The title effect is demonstrated by a comparative analysis of the rate patterns obtained for the two leaving groups.

scholarly journals The Impact of Alkaloid-Producing Epichloë Endophyte on Forage Ryegrass Breeding: A New Zealand Perspective

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Colin Eady
Keyword(s):  
Seed Production ◽  
Health Issues ◽  
Abiotic Stressors ◽  
Livestock Health ◽  
The Right ◽  
The Impact ◽  
The Relationship ◽  
And Storage ◽  
Selection Of ◽  
Epichloë Endophyte

For 30 years, forage ryegrass breeding has known that the germplasm may contain a maternally inherited symbiotic Epichloë endophyte. These endophytes produce a suite of secondary alkaloid compounds, dependent upon strain. Many produce ergot and other alkaloids, which are associated with both insect deterrence and livestock health issues. The levels of alkaloids and other endophyte characteristics are influenced by strain, host germplasm, and environmental conditions. Some strains in the right host germplasm can confer an advantage over biotic and abiotic stressors, thus acting as a maternally inherited desirable ‘trait’. Through seed production, these mutualistic endophytes do not transmit into 100% of the crop seed and are less vigorous than the grass seed itself. This causes stability and longevity issues for seed production and storage should the ‘trait’ be desired in the germplasm. This makes understanding the precise nature of the relationship vitally important to the plant breeder. These Epichloë endophytes cannot be ‘bred’ in the conventional sense, as they are asexual. Instead, the breeder may modulate endophyte characteristics through selection of host germplasm, a sort of breeding by proxy. This article explores, from a forage seed company perspective, the issues that endophyte characteristics and breeding them by proxy have on ryegrass breeding, and outlines the methods used to assess the ‘trait’, and the application of these through the breeding, production, and deployment processes. Finally, this article investigates opportunities for enhancing the utilisation of alkaloid-producing endophytes within pastures, with a focus on balancing alkaloid levels to further enhance pest deterrence and improving livestock outcomes.

scholarly journals Design Concepts for NiTiNOL Wires to Function as a Sensor

2021 ◽  
Author(s):  
D. Josephine Selvarani Ruth
Keyword(s):  
Shape Memory Alloy ◽  
Electrical Resistance ◽  
Nickel Titanium ◽  
The Other ◽  
Sensing Element ◽  
Proper Selection ◽  
Design Concepts ◽  
Mechanical Element ◽  
Selection Of ◽  
Inverse Hysteresis

AbstractNickel Titanium Naval Ordinance Laboratory (NiTiNOL) is widely called as a shape memory alloy (SMA), a class of nonlinear smart material inherited with the functionally programmed property of varying electrical resistance during the transformation enabling to be positioned as a sensing element. The major challenge to instrument the SMA wires is to suppress the wires’ nonlinearity by proper selection of two important factors. The first factor is influenced by the mechanical biasing element and the other is to identify the sensing current for the sensing device (SMA wires + biasing). This paper focuses on developing SMA wires for sensing in different orientation types and configurations by removing the non-linearity in the system’s output by introducing inverse hysteresis to the wires through the passive mechanical element.

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