Diradical Interactions in Ring-Open Isoxazole

2020 ◽  
Author(s):  
Adam A. Wallace ◽  
Yerbolat Dauletyarov ◽  
Andrei Sanov
Keyword(s):  
Ring Open

Investigation of the effects of silicone emulsions having different particle sizes on knitted fabrics depending on the type of yarn

2017 ◽  
Vol 29 (3) ◽  
pp. 394-416 ◽  
Author(s):  
Burcu Sancar Besen ◽  
Onur Balci
Keyword(s):  
Future Research ◽  
Particle Sizes ◽  
Knitted Fabrics ◽  
Content Type ◽  
Bursting Strength ◽  
Chemical Structures ◽  
Strength And Stiffness ◽  
Ring Open ◽  
Working Parameters ◽  
Physical And Chemical

Purpose The purpose of this paper is to investigate the effects of silicone-based softeners, which were developed with different particle sizes (nano, micro, and macro) and chemical structures, on the performance of 100 percent cotton fabrics knitted with different type of yarn (ring, open-end, and compact). Design/methodology/approach In the study, the silicone emulsions having expected particle sizes were produced at laboratory conditions. The produced silicone emulsions were applied to knitted fabrics with both padding and exhaust methods at different concentrations. Some characterization tests (particle size and zeta potential) were applied to the silicone emulsions before the applications. After the applications, CIELab values, whiteness and color fastness, hyrophility, abrasion, pilling, bursting strength, and stiffness performances of the samples were tested. The changes of the investigated properties were also examined via ANOVA. Findings According to the results, it was found that the silicone applications caused the CIELab values, whiteness degree, hyrophility, pilling, bursting strength and stiffness performance of the fabrics to change depending on the particle sizes of the emulsions, the yarn type of the fabrics, the application type, and the concentration of the silicone emulsions. When the ANOVA results were examined, it was seen that the types of the yarn and the silicone emulsions were the most effective working parameters on the results. Research limitations/implications Because no additives were added to the produced silicone emulsions, in the future research, they can be developed with the use of some additives. Thus, it can resolve some of the disadvantages of the silicone emulsions on the textiles. Practical implications While applying the silicone softeners to the knitted fabrics, the type of the yarn and the particle sizes of the emulsions must be determined according to each other, in order to obtain enough handle performance without causing negative change on the other important properties of the knitted fabrics. Originality/value When the studies regarding silicone softeners were investigated, it was found that there were no studies about the effect of the silicone softeners having different particle sizes on the physical and chemical structures of the knitted fabrics depending on the type of yarn and some working parameters such as concentration and type of the application.

Some Stability and Stereochemical Considerations of Simple Bicyclo[4.2.0]octanols

2005 ◽  
Vol 58 (5) ◽  
pp. 354 ◽  
Author(s):  
Wendy A. Loughlin ◽  
Catherine C. Rowen ◽  
Michelle A. McCleary
Keyword(s):  
Hydrogen Bonding ◽  
Hydrochloric Acid ◽  
Reaction Temperature ◽  
Ring Opening ◽  
Unexpected Result ◽  
Lithium Diisopropylamide ◽  
Aqueous Hydrochloric Acid ◽  
Ring Open ◽  
Short Times

Bicyclooctanols 3 and 4 were formed with control of the stereochemistry at C8 by using an aluminium enolate of cyclohexanone in 1,2-dimethoxyethane. Bicyclooctanols 1 and 3 were stable towards aqueous hydrochloric acid for short times (< 3.5 h), and ring open to a diastereomeric mix of monoalkylated 5 under protic or aprotic conditions in the presence of base (NaOH or lithium diisopropylamide). The rate of ring opening appears to be dependent on reaction temperature. Bicyclooctanols 1, 3, and 4 displayed remarkable stability when heated at reflux in benzene, whereas use of ethanol prompted stereoselective ring opening of 1 and 3 to give individual diastereomers of monoalkylated 5 and ring opening of 4 to give a 50 : 50 mix of diastereomers of 5. This unexpected result was attributed to the stereochemistry of the bicyclooctanol and placement of hydrogen-bonding sites.

Selective or living organopolymerization of a six-five bicyclic lactone to produce fully recyclable polyesters

2019 ◽  
Vol 10 (23) ◽  
pp. 3097-3106 ◽  
Author(s):  
Robin M. Cywar ◽  
Jian-Bo Zhu ◽  
Eugene Y.-X. Chen
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Room Temperature ◽  
Heterocyclic Carbenes ◽  
Base Pairs ◽  
Ring Open ◽  
Bicyclic Lactone

A ring-fused γ-butyrolactone can be selectively ring-open polymerized at room temperature by N-heterocyclic carbenes to cyclic polyester or by bifunctional (thio)urea and base pairs in a living fashion to high molecular weight linear polyester that can be organocatalytically and quantitatively recycled at 120 °C.

scholarly journals A Rectangular Ring, Open-Ended Monopole Antenna with Two Symmetric Strips for WLAN and WiMAX Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Joong-Han Yoon ◽  
Young-Chul Rhee ◽  
Woo-Su Kim
Keyword(s):  
Wireless Local Area Network ◽  
Local Area Network ◽  
Local Area ◽  
Monopole Antenna ◽  
Impedance Bandwidth ◽  
Area Network ◽  
Bandwidth Requirement ◽  
Ring Open ◽  
Peak Gain ◽  
Triple Band

A triple-band rectangular ring, open-ended monopole antenna with symmetricLstrips for wireless local area network (WLAN)/Worldwide Interoperability of Microwave Access (WiMAX) applications is proposed. The proposed antenna consists of two symmetric folded arms andLstrips. Based on the concept, a prototype of the proposed triple antenna has been designed, fabricated, and tested. The numerical and experimental results demonstrated that the proposed antenna satisfied the −10 dB impedance bandwidth requirement while simultaneously covering the WLAN and WiMAX bands. Furthermore, this paper presented and discussed the 2D radiation patterns and 3D gains according to the results of the experiment. The proposed antenna’s peak gain varied between 2.17 and 4.93 dBi, and its average gain varied between −2.97 and −0.53 dBi.

Synthesis of polyferrocenyldimethylsilane through ring-open polymerization and its electrochemical properties in different mediums

2001 ◽  
Vol 82 (13) ◽  
pp. 3258-3261 ◽  
Author(s):  
L. Wang ◽  
C. Y. Ye ◽  
P. Y. Zhang ◽  
J. Pan ◽  
Linxian Feng ◽  
...  
Keyword(s):  
Electrochemical Properties ◽  
Ring Open

Thienoisothiazoles. II. The synthesis of 5-alkylthioisothiazoles and the preparation of Thieno[3,2-d]isothiazole derivatives

1982 ◽  
Vol 35 (2) ◽  
pp. 393 ◽  
Author(s):  
FC James ◽  
HD Krebs
Keyword(s):  
Carboxylic Acid ◽  
Carbon Disulfide ◽  
Ring Opening ◽  
Hypophosphorous Acid ◽  
Bromo Derivative ◽  
Ring Open ◽  
Moderate Yield

Alkylation of the reaction product of sodium 3-iminobutyronitrile and carbon disulfide produces alkyl 2-cyano-3-iminodithiobutyrates (1) in moderate yield, which on iodine oxidation afford 5-alkylthio-3-methylisothiazole-4-carbonitriles (2b-e). Ethyl 4-amino-3-methylthieno[3,2-dliso- thiazole-5-carboxylate (3a) which was obtained by cyclization of ethyl 2-(4-cyano-3-methylisothiazol- 5-ylthio)acetate (2c) yields 3-methylthieno[3,2-d]isothiazole (3f) on deamination, hydrolysis and decarboxylation. This compound forms a 5-nitro and 5-bromo derivative. The position of the substituents was verified by synthesis. On reduction with hypophosphorous acid, 3-methylthieno- [3,2-d]isothiazole and some of its derivatives readily ring-open, yielding stable 3-acetimidoylthio-phen-2-thiols (4d-g), which are useful intermediates for the preparation of 3-acetyl-2-mercaptothiophen derivatives. Ring-opening of the isothiazole ring in 3-methylthieno[3,2-d]isothiazole (3f) and its 5-bromo derivative (3m) occurs during lithiation reactions, resulting in the formation of 3-acetyl-2-butylthiothiophen, isolated as the thiosemicarbazone (4c), and 3-acetyl-2-butylthio-thiophen-5-carboxylic acid (4b) respectively.

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