Добірка наукової літератури з теми "Para-substituted"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Para-substituted".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Para-substituted"

1

Kozlov, O. F., A. G. Yurchenko, S. D. Isaev, N. A. Leont'eva, and A. V. Nabokova. "Para-adamantyl-substituted phenylpyrazolones." Pharmaceutical Chemistry Journal 20, no. 6 (June 1986): 412–14. http://dx.doi.org/10.1007/bf00758337.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Langle, Sandrine, Franck David-Quillot, Mohamed Abarbri, and Alain Duchêne. "Synthesis of para-substituted styrenes." Tetrahedron Letters 44, no. 8 (February 2003): 1647–49. http://dx.doi.org/10.1016/s0040-4039(03)00027-3.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Mansour, El Sayed M. E., Samir K. El-Sadany, Ahmed A. Kassem, and Hamdy A. Maksoud. "Aminolysis of para-substituted benzalacetophenones." Journal of Chemical & Engineering Data 34, no. 3 (July 1989): 368–70. http://dx.doi.org/10.1021/je00057a030.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Štekláč, Marek, and Martin Breza. "DFT Studies of Substituted Phenols Cytotoxicity I. Para ‐substituted Phenols." ChemistrySelect 6, no. 28 (July 21, 2021): 7049–55. http://dx.doi.org/10.1002/slct.202101568.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Ito, Yoshikatsu, Nobuhiro Kawatsuki, Brij Pal Giri, Masahiro Yoshida, and Teruo Matsuura. "Photochemistry of meta-substituted and para-substituted aromatic polycarbonyl compounds." Journal of Organic Chemistry 50, no. 16 (August 1985): 2893–904. http://dx.doi.org/10.1021/jo00216a018.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Cihaner, Atilla, and Ahmet M. Önal. "Electrochemical Polymerization of Para‐Substituted Haloanilines." Journal of Macromolecular Science, Part A 43, no. 1 (January 2006): 153–63. http://dx.doi.org/10.1080/10601320500406032.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Zuev, Vjacheslav V., Fabio Bertini, and Guido Audisio. "Thermal degradation of para-substituted polystyrenes." Polymer Degradation and Stability 71, no. 2 (January 2001): 213–21. http://dx.doi.org/10.1016/s0141-3910(00)00113-0.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Langle, Sandrine, Franck David-Quillot, Alexia Balland, Mohamed Abarbri, and Alain Duchêne. "General access to para-substituted styrenes." Journal of Organometallic Chemistry 671, no. 1-2 (April 2003): 113–19. http://dx.doi.org/10.1016/s0022-328x(03)00053-6.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Douarre, L., R. Arnaud, J. Lemaire, A. Deflandre, and H. Richard. "Photochemical study of para-substituted anilines." Journal of Photochemistry and Photobiology A: Chemistry 87, no. 2 (March 1995): 143–50. http://dx.doi.org/10.1016/1010-6030(94)03978-4.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Wu, Biqi, and Harry S. Mosher. "Configuration of some para-substituted benzhydrols." Journal of Organic Chemistry 51, no. 10 (May 1986): 1904–6. http://dx.doi.org/10.1021/jo00360a049.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Дисертації з теми "Para-substituted"

1

Srichan, Sansanee. "Synthesis of sequence-controlled polymers by copolymerization of para-substituted styrenic derivatives and N-substituted maleimides." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF005/document.

Повний текст джерела
Анотація:
Dans ce travail, les copolymérisations radicalaires contrôlées de monomères donneurs (dérivés du styrène) et accepteurs (maleimides N-substitués) ont été effectuées afin de préparer des polymères à séquences contrôlées. Ces macromolécules ont été préparées par polymérisation radicalaire contrôlée par la voie des nitroxides en utilisant le SG1 comme agent de contrôle. Des polymères ayant des microstructures bien définies ont été obtenus par le contrôle du temps de l’addition d’une petite quantité de monomère accepteur au cours de la polymérisation d’un large excès de monomère de type donneur. Dans cette thèse, des nouveaux dérivés styréniques para-substitués ont été sélectionnés afin de préparer une variété de polymères fonctionnels à séquences contrôlées. Par exemple, des polyélectrolytes à base de poly(4-hydroxystyrène)s et poly(vinyl benzyle amine)s ont été obtenus par polymérisation de dérivés protégés du styrène (4-tert-butoxystyrène, 4-acetoxystyrène et N-(p-vinyl benzyl)phthalimide) avec une quantité non-stœchiométrique de maleimides N-substitués. Par ailleurs, des polymères PEGylés biocompatibles et solubles dans l’eau ont également été étudiés. Des polymères à séquences contrôlées portant des fonctions alcynes protégées sur chaque unité de styrène ont été dans un premier temps synthétisés. La suppression de ces groupes protecteurs a permis le greffage du α-méthoxy-ω-azido-PEG sur les fonctions alcynes libres en employant la chimie click de type CuAAC. Finalement, des polymères semi-cristallins à séquences contrôlées ont été élaborés en utilisant le styrène d’octadécyle comme monomère donneur. Les propriétés thermiques de ces polymères ont été étudiées afin d’évaluer l’influence de la microstructure sur le comportement de leur cristallisation
In this work, controlled radical copolymerizations of donor (styrenic derivatives) and acceptor monomers (N-substituted maleimides, MIs) have been investigated in order to synthesize sequence-controlled polymers. These macromolecules were prepared by nitroxide mediated polymerization using the nitroxide SG1 as a control agent. Polymers with defined microstructures were obtained by time-controlled addition of small amounts of acceptor monomers during the polymerization of a large excess of donor monomer. In this thesis, new styrenic derivatives have been studied in order to design sequence-controlled polymers with functional backbones. For example, sequence-controlled polyelectrolytes based on poly(4-hydroxystyrene)s and poly(vinyl benzyl amine)s were obtained through the polymerization of protected styrenic derivatives (i.e. 4-tert-butoxystyrene, 4-acetoxystyrene and N-(p-vinyl benzyl)phthalimide) with non-stoichiometric quantities of N-substituted maleimides. Furthermore, the preparation of PEGylated biocompatible water-soluble polymers was also investigated. Sequence-controlled polymers bearing protected alkyne functional groups on each styrene units were first synthesized followed by the removal of their protecting groups allowing the grafting of α-methoxy-ω-azido-PEG on free alkyne moieties via CuAAC mediated click reaction. Finally, sequence-controlled semi-crystalline polymers were synthesized using octadecylstyrene as a donor monomer. The thermal properties of these polymers were studied to evaluate the influence of polymer microstructure on crystallization behavior
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Ramlall, Pratima Madhuri. "Photogeneration of nitrenium ions of para-substituted phenyl azides by laser flash photolysis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0002/NQ41284.pdf.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Rautenbach, Daniel. "The development of an electrochemical process for the production of para-substituted di-hydroxy benzenes." Thesis, Nelson Mandela Metropolitan University, 2005. http://hdl.handle.net/10948/159.

Повний текст джерела
Анотація:
The project was concerned with the investigation of the electrochemical oxidation of various phenols, and to develop a viable reaction system for the production of the respective hydroquinones. Current production routes utilizing phenol as starting material have the limitations of using large amounts of acids, having to be stopped at low conversions and producing a mixture of the hydroquinones and catechols. Of the possible routes to the respective hydroquinones from the various phenols, the electrochemical oxidation of these phenols offers commercial and environmental advantages and hence formed the theme of the investigation. The synthetic possibilities proved to be more prevalent in a system when the electrochemical oxidation of these phenols was performed in an aqueous medium utilizing an organic co-solvent. Results obtained during this investigation made it possible to make certain predications about the mechanism taking place. This was found to depend on the anode material used for the oxidation. The results showed that the process developed for the electrochemical oxidation of these phenols, yields mainly the para-isomers of the respective hydroquinones and benzoquinones in good yields and selectivities, with fair current efficiencies and good mass balances at high conversions. For example: * Phenol (batch) 8 F: 345% current efficiency, 70% hydroquinone, 6% catechol, 9% benzoquinone, 9% phenol and 94 mass balance. * 2-Tert-butylphenol (flow) 10 F: 37% current efficiency, 65% hydroquinone, 33% benzoquinone, 2% phenol and 100% mass balance. * 2,6-Di-tert-butylphenol (flow) 11 F: 23% current efficiency, 92 % hydroquinone, 6% benzoquinone, 1% phenol and 99% mass balance. The developed electrochemical oxidation system offers the following advantages over previous and current methods: simplified isolation and extraction procedures, smaller amounts of acid usage, reasonably selective synthesis of the para-isomer and a less corrosive system all at high conversions.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Galvis, Pareja David Andrés. "Pharmacological evaluation of new meta- and para-hydroxyl substituted C-4-aryl-1,4-dihydropyridines in cardiomyocytes." Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/105211.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Bonano, Julie S. "Structural Determinants of Abuse-Related Neurochemical and Behavioral Effects of Para-Substituted Methcathinone Analogs in Rats." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3911.

Повний текст джерела
Анотація:
Methcathinone (MCAT) is the β-ketone analog of methamphetamine, and like its amphetamine analog, MCAT functions as a monoamine releaser that selectively promotes the release of dopamine (DA) and norepinephrine (NE) over serotonin (5-HT). MCAT produces amphetamine-like psychostimulant effects and is classified as a Schedule I drug of abuse by the United States Drug Enforcement Administration (DEA). Recently, synthetic MCAT analogs have emerged as designer drugs of abuse in Europe and the United States and have been marketed under deceptively benign names like “bath salts” in an attempt to evade legal restriction. These dangerous, recently emergent and novel drugs of abuse display varying selectivity to promote release of DA/NE vs. 5-HT, and selectivity for DA neurotransmission is believed to correlate with abuse liability. The goal of this dissertation was to conduct preclinical research to examine structural determinants of abuse-related behavioral and neurochemical effects produced by a series of synthetic MCAT analogs. Specifically, this project focused on one feature of the methcathinone scaffold: the para substituent of the benzene ring. A series of six novel MCAT analogs will be examined to evaluate how physicochemical parameters (steric, Es; electronic, σp; lipophilic, πp) of the para substituent influence in vitro monoamine transporter selectivity as well as in vivo neurochemical and behavioral effects. Results from this body of work implicate steric factors as being particularly important in determining a compound’s abuse-related neurochemical and behavioral effects. Thus, these data not only offer an improved understanding of the mechanism of abuse-related drug effects produced by synthetic MCAT analogs, but also help in the generation of homology models of the human DA and 5-HT transporters (DAT and SERT, respectively).
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Zhu, Peizhi, and 朱沛志. "Time-resolved resonance Raman and density functional theory studies ofselected para-phenyl substituted arylnitrenium ions and arylnitrenes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31246370.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Schäfer, Julian [Verfasser], and Christoph [Gutachter] Lambert. "Synthesis and Photophysical Investigation of Donor-Acceptor-Substituted meta- and para-Benzene Derivatives / Julian Schäfer ; Gutachter: Christoph Lambert." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1171132948/34.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Chan, Pik-ying, and 陳碧瑩. "Time-resolved resonance Raman investigation of selected para-substituted phenylnitrenium ions and the 2-fluorenylnitrenium ionreaction with guanosine." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36189881.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Hickman, Hazel Alice. "Towards the synthesis of alkoxy-substituted [2.2]para-cyclophenes and [2.2]para-cyclophane-1-enes : tailored monomers for the preparation of well-defined, functionalised PPV." Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/30100.

Повний текст джерела
Анотація:
This thesis describes a route towards the synthesis of alkoxy-functionalised [2.2] para-cyclophenes and [2.2]-para-cyclophane-1-enes as possible monomers for the preparation of functionalised PPVs via ROMP, using their corresponding alkoxy-functionalised stilbenes as precursors to furnish the desired cyclophenes through a ring-closing reaction. Chapter 1 is divided into three sections, A, B and C. Section A introduces the concept of conducting and electroluminescent polymers, with particular emphasis upon polyacetylene and PPV. Section B discusses stilbenes in detail, while section C examines the structure, preparation and reactivity of cyclophanes and cyclophenes, specifically [2.2] para-cyclophane and [2.2] para-cyclophene. Chapter 2 explains the synthesis of a series of alkoxy-substituted benzaldehydes, designed as easily accessible, readily functionalised precursors to alkoxy-substituted stilbenes, while Chapter 3 shows how these alkoxy-substituted benzaldehydes can be transformed into stilbenes, through the application of either the McMurry, Wittig, or Horner-Wittig reactions. Chapter 4 describes further transformations of alkoxy-substituted stilbenes, with emphasis placed upon achieving ring-closing to furnish the desired [2.2] para-cyclophenes and [2.2] para-cyclophene-1-enes. Preparation of an oligomeric form of PPV from the same stilbene precursors is also discussed, and the photophysics of both this oligomer and its related stilbenes is investigated. Chapter 5 outlines an alternative route towards alkoxy-functionalised [2.2] para-cyclophenes, via a Ramberg-Backlund rearrangement of functionalised cyclic dithioethers, and Chapter 6 gives overall conclusions for this thesis, briefly introducing possible further studies to be undertaken on this topic. Chapter 7 contains experimental details and characterisation data for all compounds prepared during the course of this work.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Chan, Pik-ying. "Time-resolved resonance Raman investigation of selected para-substituted phenylnitrenium ions and the 2-fluorenylnitrenium ion reaction with guanosine." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36189881.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Книги з теми "Para-substituted"

1

Genus, Devon. Biological synthesis of chemical and materials: Production of substituted para-polyphenylene. Lowell, Mass: Toxics Use Reduction Institute, University of Massachusetts Lowell, 1992.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Koerner, Terry. Using kinetic isotope effects to model the transition states for the sn2 reactions between sodium borohydride and para-substituted benzyl chlorides. Sudbury, Ont: Laurentian University Press, 1996.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Ramlall, Pratima Madhuri. Photogeneration of nitrenium ions of para-substituted phenyl azides by laser flash photolysis. 1999.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Частини книг з теми "Para-substituted"

1

Schultz, T. Wayne, Geoffrey W. Riggin, and Sonji K. Wesley. "Structure-Activity Relationships for Para-Substituted Phenols." In QSAR in Environmental Toxicology - II, 333–45. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3937-0_25.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Biava, M., R. Fioravanti, G. C. Porretta, L. Caruso, G. Musumarra, N. Simonetti, and A. Villa. "CARSO response surface modelling of para-substituted -N-heteroaryl benzylamines antimycotic activities." In Trends in QSAR and Molecular Modelling 92, 319–20. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1472-1_61.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Hehre, W. J., R. W. Taft, and R. D. Topsom. "Ab Initio Calculations of Charge Distributions in Monosubstituted Benzenes and in Meta- and Para-Substituted Fluorobenzenes. Comparison with 1 H, 13 C, and 19 F Nmr Substituent Shifts." In Progress in Physical Organic Chemistry, 159–87. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470171912.ch6.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Mark, James E., Dale W. Schaefer, and Gui Lin. "Types of Polysiloxanes." In The Polysiloxanes. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780195181739.003.0005.

Повний текст джерела
Анотація:
The polysiloxane of greatest commercial importance and scientific interest is poly(dimethylsiloxane) (PDMS), [Si(CH3)2 –O –]x, a member of the symmetrical dialkyl polysiloxanes, with repeat unit [SiR2 –O –]x. This polymer is discussed extensively in the following chapters, particularly in chapter 5. Other members of this series are poly(diethylsiloxane) [Si(C2H5) –O–]x, and poly(di-n-propylsiloxane) [SiC3H7)2–O–]x. An example of an aryl member of the symmetrically substituted series is poly(diphenylsiloxane), with repeat unit [Si(C6H5)2–O–]x. This polymer is unusual because of its very high melting point and the mesophase it exhibits. The closely related polymer, poly(phenyl/tolylsiloxane), has also been prepared and studied. The unsymmetrically substituted polysiloxanes have the repeat unit [SiRR’O–]x, and are exemplified by poly(methylphenylsiloxane) [Si(CH3) (C6H5) –O–]xand poly(methylhydrosiloxane) [Si(CH3)(H) –O–]x. In some cases, one of the side chains has been unusually long, for example C6H13, C16H33, and C18H37, including a branched side chain—CH(CH3– (CH2)m–CH3. Another example has methoxy-substituted aromatic fragments as one of the two side chains in the repeat unit. Such chains have stereochemical variability in analogy with the vinyl polymers such as polypropylene [CH(CH3) –CH2–]xand vinylidene polymers such as poly(methyl methacrylate) [C(CH3)(C = OOCH3) –CH2–]xOne can also introduce optically active groups as side chains, the simplest example being the secondary butyl group—CH(CH3)(C2H5). Another example involves redox-active dendritic wedges containing ferrocenyl and carbonylchromium moieties. Other substituents have included phenylethenyl groups, cyclic siloxane groups, and Cr-bound carbazole chromophores. In a reversal of roles, some polymers were prepared to have PDMS side chains on a poly(phenylacetylene) main chain. Siloxane-terminated solubilizing side chains are used to improve the properties of thin-film transistors. Silalkylene polymers have methylene groups replacing the oxygen atoms in the backbone. Poly(dimethylsilmethylene) is an example, [Si(CH3)2–CH2]x. A variation on this theme is to include aryl groups, for example, in poly(dimethyldiphenylsilylenemethylene) [Si(CH3)2CH2Si(C6H5)2]x. Other aryl substituents, specifically tolyl groups, have also been included as side chains. It is also possible to insert a silphenylene group [Si(CH3)2–C6H4–] into the backbone of the polysiloxane repeat unit to give [Si(CH3)2–C6H4– Si(CH3)2O–], in which the phenylene can be para or ortho or meta. A specific example is poly(tetramethyl-p-silphenylene-siloxane).
Стилі APA, Harvard, Vancouver, ISO та ін.
5

"Para-substituted Aniline Hydrogenation Over Rhodium Catalysts: Metal Crystallite Size and Catalyst Pore Size Effects Department of Chemistry, The University, Glasgow G12 8QQ, Scotland, U.K." In Catalysis of Organic Reactions, 101–8. CRC Press, 2005. http://dx.doi.org/10.1201/9781420028034-19.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Mark, James E., Harry R. Allcock, and Robert West. "Polysiloxanes and Related Polymers." In Inorganic Polymers. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780195131192.003.0008.

Повний текст джерела
Анотація:
At the present time, polysiloxanes are unique among inorganic and semi-inorganic polymers. They have been the most studied by far, and are the most important with regard to commercial applications. Thus, it is not surprising that a large number of review articles exist describing the synthesis, properties, and applications of these materials. The Si-O backbone of this class of polymers endows it with a variety of intriguing properties. For example, the strength of this bond gives the siloxane polymers considerable thermal stability, which is very important for their use in high-temperature application (for example as heat-transfer agents and high-performance elastomers). The nature of the bonding and the chemical characteristics of typical side groups give the chains a very low surface free energy and, therefore, highly unusual and desirable surface properties. Not surprising, polysiloxanes are much used, for example, as mold-release agents, for waterproofing garments, and as biomedical materials. Some unusual structural features of the chains give rise to physical properties that are also of considerable scientific interest. For example, the substituted Si atom and the unsubstituted O atom differ greatly in size, giving the chain a very irregular cross section. This influences the way the chains pack in the bulk, amorphous state, which, in turn, gives the chains very unusual equation-of-state properties (such as compressibilities). Also, the bond angles around the O atom are much larger than those around the Si, and this makes the planar all-trans form of the chain approximate a series of closed polygons. As a result, siloxane chains exhibit a number of interesting configurational characteristics. These structural features, and a number of properties and their associated applications, will be discussed in this chapter. The major categories of homopolymers and copolymers to be discussed are linear siloxane polymers [-SiRR'O-] (with various alkyl and aryl R,R' side groups), (ii) sesquisiloxane polymers possibly having a ladder structure, (iii) siloxane-silarylene polymers [-Si(CH3)2OSi(CH3)2(C6H4)m-] (where the skeletal phenylene units are either meta or para), (iv) silalkylene polymers [-Si(CH3)2(CH2)m-], and (v) random and block copolymers, and blends of some of the above. Topics of particular importance are the structure, flexibility, transition temperatures, permeability, and other physical properties.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Mark, James E., Dale W. Schaefer, and Gui Lin. "Introduction." In The Polysiloxanes. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780195181739.003.0003.

Повний текст джерела
Анотація:
Polysiloxanes are unique among inorganic and semi-inorganic polymers; they are also the most studied and the most important with regard to commercial applications. Thus, it’s not surprising that there is an extensive literature describing the synthesis, properties, and applications of these materials, including books, proceedings books, sections of books or encyclopedias, review articles, and historical articles. The purpose of this volume is not to give a comprehensive overview of these polymers but rather to focus on some novel and interesting aspects of polysiloxane science and engineering, including properties, work in progress, and important unsolved problems. The Si-O backbone endows polysiloxanes with a variety of intriguing properties. The strength of the Si-O bond, for example, imparts considerable thermal stability, which is important for high-temperature applications (e.g., as heat-transfer agents and high-performance elastomers). The nature of the bonding and the chemical characteristics of typical side groups impart low surface free energy and therefore desirable surface properties. Polysiloxanes, for example, are used as mold-release agents, waterproofing sprays, and biomedical materials. Structural features of the chains give rise to physical properties that are also of considerable scientific interest. For example, the substituted Si atom and the unsubstituted O atom differ greatly in size, giving the chain a nonuniform cross section. This characteristic affects the way the chains pack in the bulk, amorphous state, which explains the unusual equation-of-state properties (such as compressibility). Also, the bond angles around the O atom are much larger than those around the Si, which makes the planar all trans form of the chain approximate a series of closed polygons, as illustrated in figure 1.1. As a result, siloxane chains exhibit a number of interesting configurational characteristics that impact properties and associated applications. The major categories of homopolymers and copolymers to be discussed are (i) linear siloxane polymers -SiRR’O-] (with various alkyl and aryl R,R’ side groups), (ii) sesquisiloxane polymers possibly having a ladder structure, (iii) siloxane-silarylene polymers [–Si(CH3)2OSi(CH3)2(C6H4)m –] (where the skeletal phenylene units are either meta or para), (iv) silalkylene polymers [–Si(CH3)2(CH2)m–], and (v) random and block copolymers, and blends of some of the above.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Sridhar, Rapolu, D. Ravinder, J. Laxman Naik, K. Vijaya Kumar, N. Maramu, and S. Katlakunta. "Investigation of Structural, Magnetic and Electrical Properties of Chromium Substituted Nickel Ceramic Nanopowders." In Advanced Ceramic Materials. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.94941.

Повний текст джерела
Анотація:
Nano-ceramic of NiCrxFe2-xO4 (0.1 ≤ x ≤ 1.0) ferrites were synthesized by citrate-gel auto combustion method. The structural parameter such as lattice parameter, X-ray density, bulk density and porosity variations with Cr doping were studied. The average crystallite size is in the range 8.5–10.5 nm. The surface morphology and elemental analysis was studied with SEM (EDAX) spectrum and the structural information analyzed with FTIR spectra. Magnetic properties were discussed with Cr3+ion concentration. Electrical parameters like dc resistivity and drift mobility were reported with function of temperature and dopent concentration from room temperature to well beyond Curie temperature and explained with hopping mechanism between Fe2+↔Fe3+ ions. The activation energies in ferri and para magnetic regions were investigated. Dielectric parameters like dielectric constant, dielectric loss and ac conductivity were investigated variation with frequency and composition.
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Para-substituted"

1

Thiemann, Thies, Nuha al Soom, and Saber Elsuccary. "Preparation of methoxy-substituted para-benzoquinones." In The 20th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2016. http://dx.doi.org/10.3390/ecsoc-20-a007.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Pindjakova, Dominika, Lucia Vrablova, Tomas Strharsky, Jiri Kos, and Josef Jampilek. "Investigation of Interactions of ortho- and para-N-Aryl-Substituted 2-Trifluoromethylcinnamanilides." In ECSOC-25. Basel Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/ecsoc-25-11651.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Bedre, L. K., and B. M. Bahirwar. "Synthesis and optical study of ortho, meta and para methoxy substituted 2, 4–diphenyl quinoline." In INTERNATIONAL CONFERENCE ON “MULTIDIMENSIONAL ROLE OF BASIC SCIENCE IN ADVANCED TECHNOLOGY” ICMBAT 2018. Author(s), 2019. http://dx.doi.org/10.1063/1.5100486.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Reddy, B. Venkatram, Jai Kishan Ojha, G. Ramana Rao, P. Predeep, Mrinal Thakur, and M. K. Ravi Varma. "Vibrational Analysis of Some Substituted Methylbenzenes Part II. Transferability of Force Constants—The Case of Tetra-, Tri-methylbenzenes and Nitro-para-toluidine." In OPTICS: PHENOMENA, MATERIALS, DEVICES, AND CHARACTERIZATION: OPTICS 2011: International Conference on Light. AIP, 2011. http://dx.doi.org/10.1063/1.3643583.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Primozic, Ines, Marijana Bolant, Alma Ramic, and Srdjanka Tomic. "Preparation of novel meta and para substituted N-benzyl protected quinuclidine esters and their resolution with butyrylcholinesterase." In The 15th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2011. http://dx.doi.org/10.3390/ecsoc-15-00740.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "Para-substituted"

1

Barney, James R. A Theoretical Study of Conjugation in Para-Substituted Nitrobenzenes. Fort Belvoir, VA: Defense Technical Information Center, May 1990. http://dx.doi.org/10.21236/ada227167.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії