Influence of Basic Oxides Ratio Li2O/Al2O3, SiO2/Al2O3 and H2O/Al2O3 on Physical, Rheological and Colloidal-Chemical Properties of Lithium Containing Alumosilicate Suspensions in the System xLi2O-Al2O3-nSiO2-mH2O

2021 ◽  
Vol 1038 ◽  
pp. 193-202
Author(s):  
Sergii G. Guzii ◽  
Tetiana Kurska ◽  
Volodymyr Andronov ◽  
Mykola Adamenko
Keyword(s):  
Chemical Properties ◽  
Work Of Adhesion ◽  
Technological Equipment ◽  
Adhesion Forces ◽  
Spreading Coefficient ◽  
Main Structure ◽  
Area Of Influence ◽  
Optimal Area ◽  
New Generation ◽  
First Time

The influence of the main structure-forming oxides Li2O/Al2O3, SiO2/Al2O3 and H2O/Al2O3 on the physical, rheological and colloidal-chemical properties of lithium-containing alumosilicate suspensions xLi2O-Al2O3-nSiO2-mH2O in the system are presented for the first time. As a result of optimization, the optimal area of influence of variable factors was determined for the ratio of oxides Li2O/Al2O3 from 0.82 to 1.05 mol, SiO2/Al2O3 from 3.4 to 4.5 mol and H2O/Al2O3 from 19 to 21.5 mol, providing normative levels of properties of lithium-containing alumosilicate suspensions, namely: density from 1.4 to 1.521 g/cm3, process viscosity from 15 to 47 sec, pH from 11.15 to 11.34, surface tension from 51.4 to 60.4 mN/m, cosine of the substrate contact angle from 0, 57 to 0.91, work of adhesion forces from 97 to 116 mN/m, work of cohesion forces from 103 to 121 mN/m, work of wetting forces from 27 to 52 mN/m, wetting coefficient from 0.78 to 0.96, spreading coefficient from –5 to –20 mN/m. The data obtained will form the basis for the creation of protective materials of new generation that, in the event of emergencies, can provide both the protection of people and technological equipment, buildings and constructions.

Recent developments in low-voltage SEM of polymers

1993 ◽  
Vol 51 ◽  
pp. 866-867
Author(s):  
S.J. Krause ◽  
W.W. Adams
Keyword(s):  
Low Voltage ◽  
Chromatic Aberration ◽  
Thermal Electron ◽  
Analytical Technique ◽  
Recent Developments ◽  
Beam Currents ◽  
New Generation ◽  
First Time ◽  
Voltage Scanning ◽  
Beam Damage

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.

scholarly journals Electrodeposition of Copper and Brass Coatings with Olive-Like Structure

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1762
Author(s):  
Artur Maciej ◽  
Natalia Łatanik ◽  
Maciej Sowa ◽  
Izabela Matuła ◽  
Wojciech Simka
Keyword(s):  
Corrosion Resistance ◽  
Cathodic Current Density ◽  
Bath Composition ◽  
Cathodic Current ◽  
Corrosion Properties ◽  
Fine Grained ◽  
Electrodeposited Coating ◽  
Copper Zinc ◽  
New Generation ◽  
First Time

One method of creating a brass coating is through electrodeposition, which is most often completed in cyanide galvanic baths. Due to their toxicity, many investigations focused on the development of more environmentally friendly alternatives. The purpose of the study was to explore a new generation of non-aqueous cyanide-free baths based on 1-ethyl-3-methylimidazolium acetate ionic liquids. The study involved the formation of copper, zinc, and brass coatings. The influence of the bath composition, cathodic current density, and temperature was determined. The obtained coatings were characterized in terms of their morphology, chemical composition, phase composition, roughness, and corrosion resistance. It was found that the structure of the obtained coatings is strongly dependent on the process parameters. The three main structure types observed were as follows: fine-grained, porous, and olive-like. To the best knowledge of the authors, it is the first time the olive-like structure was observed in the case of an electrodeposited coating. The Cu-Zn coatings consisted of 19–96 at. % copper and exhibited relatively good corrosion resistance. A significant improvement of corrosion properties was found in the case of copper and brass coatings with the olive-like structure.

El español de la isla de La Graciosa desde una perspectiva prosódica

2021 ◽  
Vol 137 (2) ◽  
pp. 451-476
Author(s):  
Imelda Chaxiraxi Díaz Cabrera ◽  
Carolina Jorge Trujillo
Keyword(s):  
Canary Islands ◽  
Grammatical Morphology ◽  
Paper Format ◽  
New Generation ◽  
First Time ◽  
The Town

Abstract Manuel Alvar published the only linguistic work known on Spanish from the island of La Graciosa (Canary Islands) in 1965, focused on the town of Caleta del Sebo, to document, in the field of Linguistic geography, the ALEICan (Linguistic and ethnographic atlas of the Canary Islands [1975–1978]). Alvar’s studies used to cover the lexical, grammatical (morphology and syntax) and phonetic levels of the segmental type, but he did not consider prosodic aspects of speech which would later be incorporated into a new generation of atlases, which would go from paper format to multimedia. As the main exponent, the AMPER project (Atlas Multimédia Prosodique de l’Espace Roman) was created in 2001 and, within its framework, we intend to describe the melodic characteristics of a group of sentences emitted by a man and a woman from Caleta del Sebo, completing thus the study started by Alvar fifty-five years ago. In this way, the results will show for the first time if there is a prosodic proximity between the eighth island and the seven main islands, which have been widely described in previous works both in formal and in informal speech.

Swift catalytic reduction of hazardous pollutants by new generation microgels

Soft Matter ◽  
2021 ◽  
Author(s):  
Vinai Kumar Singh ◽  
Krishna Kumar ◽  
Nishant Singh ◽  
Rudramani Tiwari ◽  
S. Krishnamoorthi
Keyword(s):  
Catalytic Reduction ◽  
Cross Linker ◽  
Hazardous Pollutants ◽  
New Generation ◽  
First Time

In this manuscript, we first time report the new generation microgel synthesis without using any divinyl functionalized cross-linker. New generation less crosslinked microgel structure has been achieved by optimizing the...

scholarly journals A Study of Zooplankton Community in Dukan Lake, Kurdistan Region-Iraq, with a New Record of Craspedacusta sowerbii Lankester (1880) Medusa (Cnidaria: Hydrozoa)

2017 ◽  
Vol 14 (4) ◽  
pp. 735-741 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Similarity Index ◽  
Chemical Properties ◽  
Zooplankton Community ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Alkaline Side ◽  
Physical And Chemical ◽  
First Time ◽  
Jaccard's Similarity Index ◽  
And Chemical Properties

A study of Zooplankton community has been carried out at four selected sites on Dukan Lake. Samples of water and zooplankton were collected monthly for the period from July 2015 to February 2016. Some physical and chemical properties of water were studied and the results showed that the air temperature were ranged from 0 to 36.16 °C, water temperature ranged from 2.83 to 34.66 °C, hydrogen ion concentration of studied sites were found to lie in alkaline side, it was ranged between 6.87 to 8.57, electrical conductivity ranged from 190.79 to 850.08 µs.cm­¹, turbidity ranged from 0.9-7.7 NTU, and dissolved oxygen from 3.3 to 6.8 mg.l-¹ while BOD5 were ranged from 0.53 to 34.66 mg.l-¹. Concerning to the zooplankton, 37 species were identified which belonged to Cladocera (48.38%), Copepod (43.28%), Rotifera (8.23%), Targigrada (0.08%) and Cnidaria (0.1%). The medusa of Craspedacusta sowerbii Lankester (1880) was recorded for the first time in Iraq. Regarding to zooplankton community, rotifer were ranged between 0 to 690.91 ind.m-3, Copepoda from 54.55 to 5927.27 ind.m-3 and Cladocera ranged from 18.18 to 6072.73 ind.m-3. According to Shanon-Weiner index, species diversity for zooplankton invertebrates was ranged from 0.325 to 1.091 bits/ind. Jaccard’s similarity index showed that the highest similarity was recorded between site (1) and site (4) with 40.74%.

Microstrip Gas Counters

2014 ◽  
pp. 31-51
Keyword(s):  
Glass Surface ◽  
Two Dimensional ◽  
Large Area ◽  
Proportional Chamber ◽  
Microelectronic Technology ◽  
Multiwire Proportional Chamber ◽  
Dimensional Version ◽  
A Chain ◽  
New Generation ◽  
First Time

In this chapter, the first micropattern gaseous detector, the microstrip gas counter, invented in 1988 by A. Oed, is presented. It consists of alternating anode and cathode strips with a pitch of less than 1 mm created on a glass surface. It can be considered a two-dimensional version of a multiwire proportional chamber. This was the first time microelectronic technology was applied to manufacturing of gaseous detectors. This pioneering work offers new possibilities for large area planar detectors with small gaps between the anode and the cathode electrodes (less than 0.1 mm). Initially, this detector suffered from several serious problems, such as charging up of the substrate, discharges which destroyed the thin anode strips, etc. However, by efforts of the international RD28 collaboration hosted by CERN, most of them were solved. Although nowadays this detector has very limited applications, its importance was that it triggered a chain of similar developments made by various groups, and these collective efforts finally led to the creation of a new generation of gaseous detectors-micropattern detectors.

scholarly journals Beyond switches: Rotaxane- and catenane-based synthetic molecular motors

2008 ◽  
Vol 80 (1) ◽  
pp. 17-29 ◽  
Author(s):  
Euan R. Kay ◽  
David A. Leigh
Keyword(s):  
Molecular Motors ◽  
Physical Science ◽  
Statistical Physics ◽  
Biological Process ◽  
Molecular Level ◽  
Molecular Machines ◽  
Interlocked Molecules ◽  
Recent Developments ◽  
New Generation ◽  
First Time

Nature uses molecular motors and machines in virtually every significant biological process, but learning how to design and assemble simpler artificial structures that function through controlled molecular-level motion is a major challenge for contemporary physical science. The established engineering principles of the macroscopic world can offer little more than inspiration to the molecular engineer who creates devices for an environment where everything is constantly moving and being buffeted by other atoms and molecules. Rather, experimental designs for working molecular machines must follow principles derived from chemical kinetics, thermodynamics, and nonequilibrium statistical physics. The remarkable characteristics of interlocked molecules make them particularly useful for investigating the control of motion at the molecular level. Yet, the vast majority of synthetic molecular machines studied to date are simple two-state switches. Here we outline recent developments from our laboratory that demonstrate more complex molecular machine functions. This new generation of synthetic molecular machines can move continuously and progressively away from equilibrium, and they may be considered true prototypical molecular motors. The examples discussed exemplify two, fundamentally different, "Brownian ratchet" mechanisms previously developed in theoretical statistical physics and realized experimentally in molecular-level devices for the first time in these systems.

scholarly journals ‘Independent’ Kurdish Media in Syria

2016 ◽  
Vol 9 (3) ◽  
pp. 334-351 ◽  
Author(s):  
Yazan Badran ◽  
Enrico De Angelis
Keyword(s):  
Political Identity ◽  
Political Context ◽  
The Political ◽  
Television Station ◽  
Radio Stations ◽  
News Agency ◽  
Local Media ◽  
The Media ◽  
New Generation ◽  
First Time

The Syrian uprising in 2011 was accompanied by the birth of a new generation of media outlets seeking to offer alternative narratives to those of the regime. After the Kurds gained a certain level of autonomy from the Syrian regime and opposition forces, areas historically inhabited by Kurds (Rojava) have also seen the emergence of local media: for example, the television station Ronahi, magazines and newspapers such as Welat, Buyer and Shar, radio stations such as Arta FM and Welat and the ARA News agency. Indeed, for the first time in their history, Syrian Kurds have the opportunity to have an independent voice in the media landscape. In this paper we map the field of emerging Kurdish media in Syria and analyze some of the main features of these outlets, while situating them in the larger context of emerging Syrian media. Moreover, the paper explores their relationship in the current political context of the Syrian uprising and, especially, of Rojava. In doing so, we analyze the political identity that these media tend to project and address how they position themselves toward the issue of the Kurdish identity in general and in Syria in particular.

scholarly journals Unraveling the leaf-dropping behavior behind bat folivory: do bats use biological control against roost parasites?

Mammalia ◽  
2020 ◽  
Vol 84 (2) ◽  
pp. 195-200
Author(s):  
Mariana Muñoz-Romo ◽  
Paolo Ramoni-Perazzi
Keyword(s):  
Biological Control ◽  
Chemical Properties ◽  
Active Components ◽  
Control Behavior ◽  
Liquid Portion ◽  
Important Amount ◽  
Intact Leaves ◽  
Reproductive Processes ◽  
Artibeus Lituratus ◽  
First Time

AbstractFolivory in bats, the behavior of chewing bites of leaves to extract the liquid portion and discard the fiber as oral pellets, is seen as a strategy that might provide vitamins, micronutrients and proteins not always available in fruits, and even secondary metabolites (hormonal precursors) that stimulate/inhibit reproductive processes. While examining chewed leaves, we noticed an important amount of completely intact leaves below the roosts of Artibeus amplus and Artibeus lituratus, and decided to systematically quantify them during a year. We recovered 639 intact leaves from six plant species and found that both species are constantly feeding on leaves, but invariably leaving 26–78% of these intact, dropping them on the floor just below their roosting sites. These large proportions of dropped, intact leaves suggest a completely different, novel, non-nutritional use by bats. Several studies in birds have revealed that fresh leaves are effectively used in nests to control diverse organisms that include blood suckling ectoparasites, protozoans, fungus and bacteria. We report for the first time this biological control behavior performed by bats by selecting, bringing and dropping intact leaves below their roosting sites. The chemical properties of the leaves need to be investigated to reveal those active components against specific pathogens.

scholarly journals Chemical enrichment and host galaxies of extremely strong intervening DLAs towards quasars

2020 ◽  
Vol 633 ◽  
pp. A125 ◽  
Author(s):  
A. Ranjan ◽  
P. Noterdaeme ◽  
J.-K. Krogager ◽  
P. Petitjean ◽  
R. Srianand ◽  
...  
Keyword(s):  
Star Formation ◽  
Column Density ◽  
Formation Rate ◽  
Chemical Properties ◽  
Metal Species ◽  
Host Galaxies ◽  
Chemical Enrichment ◽  
Long Duration ◽  
First Time ◽  
High Column

We present the results from VLT/X-shooter spectroscopic observations of 11 extremely strong intervening damped Lyman-α absorbers (ESDLAs) that were initially selected as high N(H I) (i.e. ≥5 × 1021 cm−2) candidates from the Sloan Digital Sky Survey (SDSS). We confirm the high H I column densities, which we measure to be in the range log N(H I) = 21.6 − 22.4. Molecular hydrogen is detected with high column densities (N(H2)≥1018 cm−2) in 5 out of 11 systems, 3 of which are reported here for the first time, and we obtain conservative upper limits on N(H2) for the remaining 6 systems. We also measure the column density of various metal species (Zn II, Fe II, Si II, Cr II, and C I), quantify the absorption-line kinematics (Δv90), and estimate the extinction of the background quasar light (AV) by dust in the absorbing gas. We compare the chemical properties of this sample of ESDLAs, supplemented with literature measurements, to that of DLAs located at the redshift of long-duration γ-ray bursts (GRB-DLAs). We confirm that the two populations are almost indistinguishable in terms of chemical enrichment and gas kinematics. In addition, we find no marked differences in the incidence of H2. All this suggests that ESDLAs and GRB-DLAs probe similar galactic environments. We search for the galaxy counterparts of ESDLAs and find associated emission lines in 3 out of 11 systems, 2 of which are reported here for the first time (at zabs = 2.304 and 2.323 towards the quasars SDSS J002503.03+114547.80 and SDSS J114347.21+142021.60, respectively). The measured separations between the quasar sightlines and the emission associated with the ESDLA galaxy (for a total of five sightlines) are all very small (ρ <  3 kpc). Because our observations are complete up to ρ ∼ 7 kpc, we argue that the emission counterparts of the remaining systems are more likely below the detection limit than outside the search area. While the small impact parameters are similar to what is observed for GRB-DLAs, the associated star formation rates are on average lower than for GRB host galaxies. This is explained by long-duration GRBs being associated with the death of massive stars and therefore pinpointing regions of active star formation in the GRB host galaxies. Our observations support the suggestion from the literature that ESDLAs could act as blind analogues of GRB-DLAs, probing neutral gas with high column density in the heart of high-redshift galaxies, without any prior on the instantaneous star formation rate.

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