New, Aqueous Radical (Co)Polymerization of Olefins at Low Temperature and Pressure

In this communication, we describe our preliminary results for the development of a new method of ethylene and propene (co)polymerization at low pressure at room temperature, using cyclodextrin-assisted aqueous radical polymerization for the first time. For polypropylene homopolymerization, the cyclodextrin was entirely removed, and the partially soluble polymer was characterized. The purification of polyethylene was not complete, since the threaded cyclodextrins remained on the polymer chain, enhancing its solubility and enable to analyze the sample. With this environmentally benign method, polyolefines could be produced, for the first time. The estimated yield was low, and therefore the conditions should be further tuned for industrial application. This straightforward approach could also be applied to synthesize poly(ethylene-co-vinyl acetate) copolymer with an ethylene content of 20 mol% and enhanced yield. Although the procedure in this stage of research has some limitations, the theory behind can later be applied to develop new, energy-efficient, and versatile industrial processes for olefin copolymerizations for a wide range of comonomers.

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The Viscosity-Temperature-Pressure Relationship of Lubricating Oils and Its Correlation With Chemical Constitution

Journal of Basic Engineering ◽

10.1115/1.3656919 ◽

1963 ◽

Vol 85 (4) ◽

pp. 601-607 ◽

Cited By ~ 167

Author(s):

C. J. A. Roelands ◽

J. C. Vlugter ◽

H. I. Waterman

Keyword(s):

Carbon Distribution ◽

Empirical Formulas ◽

Mineral Oils ◽

Quantitative Correlation ◽

Wide Range ◽

Chemical Constitution ◽

Temperature And Pressure ◽

The One ◽

Relationship Of ◽

First Time

Viscosities of twenty well-defined, representative mineral-oil fractions have been determined at temperatures from 25 to 90 deg C (77 to 194 deg F) and at pressures up to about 1000 atmospheres (15,000 psi) with the aid of a falling-needle viscometer. An analysis has been made of both the present measurements and reliable data from literature, which chiefly concern mineral oils and pure hydrocarbons, but also include some silicones, fatty oils, and alcohols. Many literature data cover ranges of viscosity, temperature, and pressure that are more extensive than those of the authors. Newly developed empirical formulas are presented for the isobaric viscosity-temperature relationship, the isothermal viscosity-pressure relationship, and the complete viscosity-temperature-pressure relationship. The formulas have been found to be satisfactorily applicable to all the aforementioned liquids in a wide range, that is, generally, from about 20 to 150 deg C (68 to 302 deg F) and up to pressures of at least 3000 atmospheres (44,000 psi). Diagrams derived from these formulas have proved particularly suitable for a systematic study of the correlation between, on the one hand, the temperature and pressure variation of viscosity of the liquids concerned and, on the other hand, their chemical constitution. This is exemplified by the results for the mineral oils investigated. In fact, it proved possible, presumably for the first time, to establish for mineral oils a really satisfactory quantitative correlation between their viscosity-temperature-pressure dependence and their chemical constitution; the latter has been characterized by the carbon distribution according to the “Waterman analysis” in the form of the so-called n-d-M method.

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Safety assessment of biological raw materials in the system of medicines quality assurance

10.33920/med-06-2002-05 ◽

2020 ◽

pp. 63-72

Author(s):

Yu. Olefir ◽

E. Sakanyan ◽

I. Osipova ◽

V. Dobrynin ◽

M. Smirnova ◽

...

Keyword(s):

Raw Materials ◽

State Level ◽

The State ◽

Spongiform Encephalopathy ◽

Safety Standards ◽

Wide Range ◽

The Russian Federation ◽

Key Aspects ◽

First Time ◽

Medicines Quality

The entry of a wide range of biotechnological products into the pharmaceutical market calls for rein-forcement of the quality, efficacy and safety standards at the state level. The following general monographs have been elaborated for the first time to be included into the State Pharmacopoeia of the Russian Federation, XIV edition: "Viral safety" and "Reduction of the risk of transmitting animal spongiform encephalopathy via medicinal products". These general monographs were elaborated taking into account the requirements of foreign pharmacopoeias and the WHO recommendations. The present paper summarises the key aspects of the monographs.

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Innovation in Byzantine Medicine

10.1093/oso/9780198850687.001.0001 ◽

2020 ◽

Author(s):

Petros Bouras-Vallianatos

Keyword(s):

Human Physiology ◽

Medical Literature ◽

Cultural Exchange ◽

Significant Degree ◽

Medieval Medicine ◽

Medieval Latin ◽

Main Thesis ◽

Wide Range ◽

Comprehensive Examination ◽

First Time

Byzantine medicine is still a little-known and misrepresented field not only in the wider arena of debates on medieval medicine but also among Byzantinists. Byzantine medical literature is often viewed as ‘stagnant’ and mainly preserving ancient ideas; and our knowledge of it continues to be based to a great extent on the comments of earlier authorities, which are often repeated uncritically. This book presents the first comprehensive examination of the medical corpus of, arguably, the most important late Byzantine physician John Zacharias Aktouarios (c.1275–c.1330). The main thesis is that John’s medical works show an astonishing degree of openness to knowledge from outside Byzantium combined with a significant degree of originality, in particular, in the fields of uroscopy, pharmacology, and human physiology. The analysis of John’s edited (On Urines and On Psychic Pneuma) and unedited (Medical Epitome) works is supported for the first time by the consultation of a large number of manuscripts. The study is also informed by evidence from a wide range of medical sources, including previously unpublished ones, and texts from other genres, such as epistolography and merchants’ accounts. The contextualization of John’s works sheds new light on the development of Byzantine medical thought and practice, and enhances our understanding of the late Byzantine social and intellectual landscape. Finally, John’s medical observations are also examined in the light of examples from the medieval Latin and Islamic worlds, placing his medical theories in the wider Mediterranean milieu and highlighting the cultural exchange between Byzantium and its neighbours.

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Rebels, Believers, Survivors

10.1093/oso/9780198857297.001.0001 ◽

2020 ◽

Author(s):

Noel Malcolm

Keyword(s):

Catholic Church ◽

Religious Conversion ◽

Late Nineteenth Century ◽

Napoleonic Wars ◽

Conversion To Islam ◽

Wide Range ◽

History Of ◽

External Powers ◽

First Time ◽

Modern Myth

This book of essays covers a wide range of topics in the history of Albania and Kosovo. Many of the essays illuminate connections between the Albanian lands and external powers and interests, whether political, military, diplomatic or religious. Such topics include the Habsburg invasion of Kosovo in 1689, the manoeuvrings of Britain and France towards the Albanian lands during the Napoleonic Wars, the British interest in those lands in the late nineteenth century, and the Balkan War of 1912. On the religious side, essays examine ‘crypto-Christianity’ in Kosovo during the Ottoman period, the stories of conversion to Islam revealed by Inquisition records, the first theological treatise written in Albanian (1685), and the work of the ‘Apostolic Delegate’ who reformed the Catholic Church in early twentieth-century Albania. Some essays bring to life ordinary individuals hitherto unknown to history: women hauled before the Inquisition, for example, or the author of the first Albanian autobiography. The longest essay, on Ali Pasha, tells for the first time the full story of the role he played in the international politics of the Napoleonic Wars. Some of these studies have been printed before (several in hard-to-find publications, and one only in Albanian), but the greater part of this book appears here for the first time. This is not only a contribution to Albanian and Balkan history it also engages with many broader issues, including religious conversion, methods of enslavement within the Ottoman Empire, and the nature of modern myth-making about national identity.

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Recycling and Reuse in the Roman Economy

10.1093/oso/9780198860846.001.0001 ◽

2020 ◽

Keyword(s):

Building Materials ◽

Computational Modelling ◽

Late Antique ◽

Roman Economy ◽

Wide Range ◽

The Status ◽

Recent Developments ◽

Methodological Approaches ◽

First Time ◽

Site Types

The recycling and reuse of materials and objects were extensive in the past, but have rarely been embedded into models of the economy; even more rarely has any attempt been made to assess the scale of these practices. Recent developments, including the use of large datasets, computational modelling, and high-resolution analytical chemistry, are increasingly offering the means to reconstruct recycling and reuse, and even to approach the thorny matter of quantification. Growing scholarly interest in the topic has also led to an increasing recognition of these practices from those employing more traditional methodological approaches, which are sometimes coupled with innovative archaeological theory. Thanks to these efforts, it has been possible for the first time in this volume to draw together archaeological case studies on the recycling and reuse of a wide range of materials, from papyri and textiles, to amphorae, metals and glass, building materials and statuary. Recycling and reuse occur at a range of site types, and often in contexts which cross-cut material categories, or move from one object category to another. The volume focuses principally on the Roman Imperial and late antique world, over a broad geographical span ranging from Britain to North Africa and the East Mediterranean. Last, but not least, the volume is unique in focusing upon these activities as a part of the status quo, and not just as a response to crisis.

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A Virtual Telescope for the Open University Science Foundation Course

International Astronomical Union Colloquium ◽

10.1017/s0252921100114885 ◽

1998 ◽

Vol 162 ◽

pp. 100-105

Author(s):

Andrew J. Norton ◽

Mark H. Jones

Keyword(s):

Social Science ◽

Open University ◽

Distance Teaching ◽

The Arts ◽

Wide Range ◽

University Science ◽

First Time ◽

Degree Level ◽

Selection Of

The Open University is the UK's foremost distance teaching university. For over twenty five years we have been presenting courses to students spanning a wide range of degree level and vocational subjects. Since we have no pre-requisites for entry, a major component of our course profile is a selection of foundation courses comprising one each in the Arts, Social Science, Mathematics, Technology and Science faculties. The Science Faculty's foundation course is currently undergoing a substantial revision. The new course, entitled “S103: Discovering Science”, will be presented to students for the first time in 1998.

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New Transition and Energy Levels of Three-Times Ionized Krypton (Kr IV)

Atoms ◽

10.3390/atoms9030048 ◽

2021 ◽

Vol 9 (3) ◽

pp. 48

Author(s):

M. Raineri ◽

M. Gallardo ◽

J. Reyna Almandos ◽

A. G. Trigueiros ◽

C. J. B. Pagan

Keyword(s):

Transition Probabilities ◽

Energy Levels ◽

Pulsed Discharge ◽

Core Polarization ◽

Polarization Effects ◽

Hartree Fock ◽

Theta Pinch ◽

New Energy ◽

First Time

A capillary pulsed-discharge and a theta-pinch were used to record Kr spectra in the region of 330–4800 Å. A set of 168 transitions of these spectra were classified for the first time. We extended the analysis to twenty-five new energy levels belonging to 3s23p24d, 3s23p25d even configurations. We calculated weighted transition probabilities (gA) for all of the experimentally observed lines and lifetimes for new energy levels using a relativistic Hartree–Fock method, including core-polarization effects.

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ChCl: Gly (DESs) Promote Environmentally Benign Synthesis of Xanthene Derivatives and Their Antitubercular Activity

Molecules ◽

10.3390/molecules26123667 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3667

Author(s):

Mashooq A. Bhat ◽

Ahmed M. Naglah ◽

Siddique Akber Ansari ◽

Hanaa M. Al-Tuwajiria ◽

Abdullah Al-Dhfyan

Keyword(s):

Reaction Times ◽

Antitubercular Activity ◽

Antimycobacterial Activity ◽

Environmentally Benign ◽

Reaction Yield ◽

Benign Synthesis ◽

Xanthene Derivatives ◽

Wide Range ◽

Major Application

A ChCl: Gly (DESs) promoted environmentally benign method was developed for the first time using the reaction of aryl aldehydes and dimedone to give excellent yields of xanthene analogues. The major application of this present protocol is the use of green solvent, a wide range of substrate, short reaction times, ease of recovery, the recyclability of the catalyst, high reaction yield, and ChCl: Gly as an alternative catalyst and solvent. In addition to this, all the synthesized compounds were evaluated for their in vitro antimycobacterial activity against M. tuberculosis H37Ra (MTB) and M. bovis BCG strains. The compounds 3d, 3e, 3f, and 3j showed significant antitubercular activity against MTB and M. bovis strains with minimum inhibitory concentration (MIC) values of 2.5−15.10 µg/mL and 0.26–14.92 µg/mL, respectively. The compounds 3e, 3f, and 3j were found to be nontoxic against MCF-7, A549, HCT 116, and THP-1 cell lines. All the prepared compounds were confirmed by 1H NMR and 13C NMR analysis.

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Autophagy Deficiency by Atg4B Loss Leads to Metabolomic Alterations in Mice

Metabolites ◽

10.3390/metabo11080481 ◽

2021 ◽

Vol 11 (8) ◽

pp. 481

Author(s):

Gemma G. Martínez-García ◽

Raúl F. Pérez ◽

Álvaro F. Fernández ◽

Sylvere Durand ◽

Guido Kroemer ◽

...

Keyword(s):

Skeletal Muscle ◽

Amino Acids ◽

Mammalian Cells ◽

Tissue Homeostasis ◽

In Vivo Studies ◽

Protective Mechanism ◽

Cardiac Damage ◽

Wide Range ◽

First Time

Autophagy is an essential protective mechanism that allows mammalian cells to cope with a variety of stressors and contributes to maintaining cellular and tissue homeostasis. Due to these crucial roles and also to the fact that autophagy malfunction has been described in a wide range of pathologies, an increasing number of in vivo studies involving animal models targeting autophagy genes have been developed. In mammals, total autophagy inactivation is lethal, and constitutive knockout models lacking effectors of this route are not viable, which has hindered so far the analysis of the consequences of a systemic autophagy decline. Here, we take advantage of atg4b−/− mice, an autophagy-deficient model with only partial disruption of the process, to assess the effects of systemic reduction of autophagy on the metabolome. We describe for the first time the metabolic footprint of systemic autophagy decline, showing that impaired autophagy results in highly tissue-dependent alterations that are more accentuated in the skeletal muscle and plasma. These changes, which include changes in the levels of amino-acids, lipids, or nucleosides, sometimes resemble those that are frequently described in conditions like aging, obesity, or cardiac damage. We also discuss different hypotheses on how impaired autophagy may affect the metabolism of several tissues in mammals.

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