scholarly journals The manganese complex of 2,3,7,8,12,13,17,18-octaphenylporphyrin as epoxidation catalyst

2001 ◽  
Vol 05 (04) ◽  
pp. 428-430 ◽  
Author(s):  
ABÍLIO J. F. N. SOBRAL ◽  
ANTÓNIO M. D'A. ROCHA GONSALVES
Keyword(s):  
Comparative Study ◽  
Manganese Complex ◽  
Reaction Conditions ◽  
The Stability ◽  
Epoxidation Catalyst

The 2,3,7,8,12,13,17,18-octaphenylporphyrinato manganese(III) chloride was prepared and its behaviour as epoxidation catalyst was studied. The role of the phenyl substituents in the ß-pyrrolic positions concerning the stability of the catalyst to the reaction conditions and the efficiency and selectivity of the oxidations was accessed in a comparative study with MnTPP and MnEtio II.

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

Provision of Remedies for Violation of Economic, Social and Cultural Rights: A Comparative Study of the United Nations, Inter-American and African Human Rights Systems

2020 ◽  
Vol 28 (2) ◽  
pp. 298-318
Author(s):  
Roman Girma Teshome
Keyword(s):  
Human Rights ◽  
United Nations ◽  
Comparative Study ◽  
Economic Rights ◽  
Regional Monitoring ◽  
Cultural Rights ◽  
The Past ◽  
The United Nations ◽  
To Receive

The effectiveness of human rights adjudicative procedures partly, if not most importantly, hinges upon the adequacy of the remedies they grant and the implementation of those remedies. This assertion also holds water with regard to the international and regional monitoring bodies established to receive individual complaints related to economic, social and cultural rights (hereinafter ‘ESC rights’ or ‘socio-economic rights’). Remedies can serve two major functions: they are meant, first, to rectify the pecuniary and non-pecuniary damage sustained by the particular victim, and second, to resolve systematic problems existing in the state machinery in order to ensure the non-repetition of the act. Hence, the role of remedies is not confined to correcting the past but also shaping the future by providing reforming measures a state has to undertake. The adequacy of remedies awarded by international and regional human rights bodies is also assessed based on these two benchmarks. The present article examines these issues in relation to individual complaint procedures that deal with the violation of ESC rights, with particular reference to the case laws of the three jurisdictions selected for this work, i.e. the United Nations, Inter-American and African Human Rights Systems.

cAbdullah Yūsuf cAlī & Muhammad Asad: Two Approaches to the English Translation of the Qur'an

2000 ◽  
Vol 2 (1) ◽  
pp. 107-123 ◽  
Author(s):  
Muzaffar Iqbal
Keyword(s):  
Twentieth Century ◽  
Comparative Study ◽  
Life Experiences ◽  
Academic Career ◽  
British India ◽  
Human Understanding ◽  
English Translations ◽  
Political Milieu ◽  
The Times

This article attempts to present a comparative study of the role of two twentieth-century English translations of the Qur'an: cAbdullah Yūsuf cAlī's The Meaning of the Glorious Qur'ān and Muḥammad Asad's The Message of the Qur'ān. No two men could have been more different in their background, social and political milieu and life experiences than Yūsuf cAlī and Asad. Yūsuf 'Alī was born and raised in British India and had a brilliant but traditional middle-class academic career. Asad traversed a vast cultural and geographical terrain: from a highly-disciplined childhood in Europe to the deserts of Arabia. Both men lived ‘intensely’ and with deep spiritual yearning. At some time in each of their lives they decided to embark upon the translation of the Qur'an. Their efforts have provided us with two incredibly rich monumental works, which both reflect their own unique approaches and the effects of the times and circumstances in which they lived. A comparative study of these two translations can provide rich insights into the exegesis and the phenomenon of human understanding of the divine text.

THE ROLE OF ATMOSPHERICS AS AN ANTECEDENT OF AIRPORT AND COUNTRY IMAGE: A COMPARATIVE STUDY

2020 ◽  
Vol 2020 ◽  
pp. 1457-1461
Author(s):  
Pantelitsa Yerimou ◽  
◽  
George Panigyrakis
Keyword(s):  
Comparative Study ◽  
Country Image

The Role of Hydrophobicity in the Stability and pH-Switchability of (RXDX)4 and Coumarin-RXDX Conjugate β-Sheets

2020 ◽  
Author(s):  
Ryan Weber ◽  
Martin McCullagh
Keyword(s):  
Biological Imaging ◽  
Ph Sensing ◽  
Hydrophobic Residue ◽  
Ideal Candidate ◽  
Self Assembling ◽  
Sensing Applications ◽  
Β Sheets ◽  
The Stability ◽  
Dynamics Simulations

<p>pH-switchable, self-assembling materials are of interest in biological imaging and sensing applications. Here we propose that combining the pH-switchability of RXDX (X=Ala, Val, Leu, Ile, Phe) peptides and the optical properties of coumarin creates an ideal candidate for these materials. This suggestion is tested with a thorough set of all-atom molecular dynamics simulations. We first investigate the dependence of pH-switchabiliy on the identity of the hydrophobic residue, X, in the bare (RXDX)<sub>4</sub> systems. Increasing the hydrophobicity stabilizes the fiber which, in turn, reduces the pH-switchabilty of the system. This behavior is found to be somewhat transferable to systems in which a single hydrophobic residue is replaced with a coumarin containing amino acid. In this case, conjugates with X=Ala are found to be unstable and both pHs while conjugates with X=Val, Leu, Ile and Phe are found to form stable β-sheets at least at neutral pH. The (RFDF)<sub>4</sub>-coumarin conjugate is found to have the largest relative entropy value of 0.884 +/- 0.001 between neutral and acidic coumarin ordering distributions. Thus, we posit that coumarin-(RFDF)<sub>4</sub> containing peptide sequences are ideal candidates for pH-sensing bioelectronic materials.</p>

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