scholarly journals Direct link between mechanical stability in gels and percolation of isostatic particles

2019 ◽  
Vol 5 (5) ◽  
pp. eaav6090 ◽  
Author(s):  
Hideyo Tsurusawa ◽  
Mathieu Leocmach ◽  
John Russo ◽  
Hajime Tanaka
Keyword(s):  
Mechanical Stability ◽  
Construction Materials ◽  
Separation Process ◽  
Medical Applications ◽  
Colloidal Gels ◽  
Direct Link ◽  
Equilibrium Thermodynamic ◽  
Phase Separation Process ◽  
Long Time ◽  
The Stability

Colloidal gels have unique mechanical and transport properties that stem from their bicontinuous nature, in which a colloidal network is intertwined with a viscous solvent, and have found numerous applications in foods, cosmetics, and construction materials and for medical applications, such as cartilage replacements. So far, our understanding of the process of colloidal gelation is limited to long-time dynamical effects, where gelation is viewed as a phase separation process interrupted by the glass transition. However, this purely out-of-equilibrium thermodynamic picture does not address the emergence of mechanical stability. With confocal microscopy experiments, we reveal that mechanical metastability is reached only after isotropic percolation of locally isostatic environments, establishing a direct link between the load-bearing ability of gels and the isostaticity condition. Our work suggests an operative description of gels based on mechanical equilibrium and isostaticity, providing the physical basis for the stability and rheology of these materials.

An analysis of the transport properties and mechanical stability of rapidly solidified Al-Sb alloy

2015 ◽  
Vol 10 (2) ◽  
pp. 2663-2681
Author(s):  
Rizk El- Sayed ◽  
Mustafa Kamal ◽  
Abu-Bakr El-Bediwi ◽  
Qutaiba Rasheed Solaiman
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Melt Spinning ◽  
Elastic Moduli ◽  
Mechanical Stability ◽  
Microstructural Analysis ◽  
Alloy System ◽  
Antimony Content ◽  
The Stability ◽  
Rapidly Solidified

The structure of a series of AlSb alloys prepared by melt spinning have been studied in the as melt–spun ribbons  as a function of antimony content .The stability  of these structures has  been  related to that of the transport and mechanical properties of the alloy ribbons. Microstructural analysis was performed and it was found that only Al and AlSb phases formed for different composition.  The electrical, thermal and the stability of the mechanical properties are related indirectly through the influence of the antimony content. The results are interpreted in terms of the phase change occurring to alloy system. Electrical resistivity, thermal conductivity, elastic moduli and the values of microhardness are found to be more sensitive than the internal friction to the phase changes. 

Sustainability and adaptability of regional development in the conditions of digitalization

2020 ◽  
Vol 19 (9) ◽  
pp. 1550-1613
Author(s):  
O.E. Akimova ◽  
S.K. Volkov ◽  
E.A. Gladkaya ◽  
I.M. Kuzlaeva
Keyword(s):  
Sustainable Development ◽  
Regional Development ◽  
Economic Behavior ◽  
Regional Inequality ◽  
Environmental Damage ◽  
Economic Potential ◽  
Human Welfare ◽  
Long Time ◽  
The Stability ◽  
Smart Technologies

Subject. The article discusses the sustainability of regional economy development, its definition, and the substance of sustainable development. Objectives. We aim at performing a comprehensive analysis of indicators of sustainability and adaptability of regional development in the context of digitalization, formulating a strategy for economic behavior that takes into account the multidimensional nature of regional inequality and is focused on boosting the economic potential of regions. Methods. The study draws on dialectic and systems approaches, general scientific methods of retrospective, situational, economic and statistical, and comparative analysis. Results. The sustainability of the region focuses on improving the human welfare over long time horizon. This happens in three areas, i.e. maximizing the efficiency of resource use; ensuring justice and democracy; minimizing resource consumption and environmental damage. The stability of the region can be assessed by using one parameter, or by combining the parameters in accordance with the type of region and expected results. Conclusions. The adaptation of a region to changing conditions depends on its type (‘adapted’, ‘adaptive’, and ‘non-adapted’). Regional inequality has two main components: difference in economic potential and social satisfaction of residents. Another component, affecting the stability and adaptability of regions, is the level of their digitalization. However, some regions have only formally embarked on the path of digitalization. Moreover, a focus on smart technologies, solutions and digitalization often leads to ignoring the goals of sustainable development. Smart technologies should be aimed at ensuring sustainability within the framework of the smart sustainable city concept.

scholarly journals Climate Change and Internet of Things Technologies—Sustainable Premises of Extending the Culture of the Amurg Cultivar in Transylvania—A Use Case for Târnave Vineyard

2021 ◽  
Vol 13 (15) ◽  
pp. 8170
Author(s):  
Veronica Sanda Chedea ◽  
Ana-Maria Drăgulinescu  ◽  
Liliana Lucia Tomoiagă  ◽  
Cristina Bălăceanu ◽  
Maria Lucia Iliescu 
Keyword(s):  
Climate Change ◽  
Weather Conditions ◽  
White Wine ◽  
Time Investment ◽  
Protected Designation Of Origin ◽  
Average Annual Temperature ◽  
Insect Infestations ◽  
Long Time ◽  
The Stability ◽  
Red Grape

Known for its dry and semi-dry white wine, the Târnave vineyard located in central Transylvania is challenged by the current climate change, which has resulted in an increase of the period of active vegetation by approximately 15–20 days, the average annual temperature by 1–1.5 °C and also the amount of useful temperatures (useful thermal balance for the grapevine). Furthermore, the frost periods have been reduced. Transylvania is an important Romanian region for grapevine cultivation. In this context, one can use the climatic changes to expand their wine assortment by cultivating an autochthonous grapevine variety called Amurg. Amurg is a red grape cultivar homologated at SCDVV Blaj, which also homologated 7 cultivars and 11 clones. Because viticulture depends on the stability of meteorological and hydrological parameters of the growing area, its foundations are challenged by climate change. Grapevine production is a long time investment, taking at least five years before the freshly planted vines produce the desired quality berries. We propose the implementation of a climate change-based precision viticulture turn-key solution for environmental monitoring in the Târnave vineyard. This solution aims to evaluate the grapevine’s micro-climate to extend the sustainable cultivation of the Amurg red grapes cultivar in Transylvania with the final goal of obtaining Protected Designation of Origin (PDO) rosé and red wines from this region. Worldwide, the changing conditions from the existing climate (a 30-year average), used in the past hundred years to dictate local standards, such as new and erratic trends of temperature and humidity regimes, late spring freezes, early fall frosts, storms, heatwaves, droughts, area wildfires, and insect infestations, would create dynamic problems for all farmers to thrive. These conditions will make it challenging to predict shifts in each of the components of seasonal weather conditions. Our proposed system also aims to give a solution that can be adapted to other vineyards as well.

scholarly journals Genipin as An Emergent Tool in the Design of Biocatalysts: Mechanism of Reaction and Applications

Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1035 ◽  
Author(s):  
Veymar G. Tacias-Pascacio ◽  
Esmeralda García-Parra ◽  
Gilber Vela-Gutiérrez ◽  
Jose J. Virgen-Ortiz ◽  
Ángel Berenguer-Murcia ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Controlled Drug Delivery ◽  
Medical Applications ◽  
Fruit Extract ◽  
Biological Scaffolds ◽  
Gardenia Jasminoides ◽  
Mechanism Of Reaction ◽  
Low Toxicity ◽  
Activating Agent ◽  
The Stability

Genipin is a reagent isolated from the Gardenia jasminoides fruit extract, and whose low toxicity and good crosslinking properties have converted it into a reactive whose popularity is increasing by the day. These properties have made it widely used in many medical applications, mainly in the production of chitosan materials (crosslinked by this reactive), biological scaffolds for tissue engineering, and nanoparticles of chitosan and nanogels of proteins for controlled drug delivery, the genipin crosslinking being a key point to strengthen the stability of these materials. This review is focused on the mechanism of reaction of this reagent and its use in the design of biocatalysts, where genipin plays a double role, as a support activating agent and as inter- or intramolecular crosslinker. Its low toxicity makes this compound an ideal alterative to glutaraldehyde in these processes. Moreover, in some cases the features of the biocatalysts prepared using genipin surpassed those of the biocatalysts prepared using other standard crosslinkers, even disregarding toxicity. In this way, genipin is a very promising reagent in the design of biocatalysts.

Distribution of Acidity and Alkalinity on Degraded Manuscripts Containing Iron Gall Ink

2015 ◽  
Vol 36 (3) ◽  
Author(s):  
Eva Marín ◽  
Maria Carme Sistach ◽  
Jessica Jiménez ◽  
Miguel Clemente ◽  
Guillem Garcia ◽  
...  
Keyword(s):  
Good Condition ◽  
Degradation Process ◽  
Degradation Processes ◽  
Alkaline Reserve ◽  
Hydrolysis Of Cellulose ◽  
Relevant Variables ◽  
Long Time ◽  
Iron Gall ◽  
The Stability

AbstractLong-time preservation of manuscripts depends on the stability of their support. One of the most important degradation processes of paper manuscripts containing iron gall ink is the acid hydrolysis of cellulose. The heterogeneity of the distribution of their constituent materials, together with the defined position of ink as a source of degradation agents, makes it difficult to obtain reliable and detailed information about degradation processes. The aim of this study is to contribute to the knowledge of the acid degradation process by looking at the distribution of relevant variables (pH, acidity and alkaline reserve) on real untreated iron gall ink containing manuscripts at different degradation stages. The study discusses the well-known differences between surface and cold extraction pH determination. It corroborates the relationship between pH, acidity and alkalinity and degradation stages, pointing out that acidity values for some manuscripts in apparent good condition are not far from those obtained for degraded manuscripts. The results indicate that in some partially degraded manuscripts, the coexistence of acid areas and areas with an alkaline reserve which do not participate in the neutralization process is possible. The role of water as a solvent for this equilibrium has also been evaluated.

World 2021: Pandemic and economic problems remain acute

2021 ◽  
pp. 5-20
Author(s):  
M. V. Ershov
Keyword(s):  
Economic System ◽  
Global Economy ◽  
Large Scale ◽  
Real Economy ◽  
Economic Problems ◽  
Support Measures ◽  
Long Time ◽  
Digital Money ◽  
Successful Business ◽  
The Stability

The global economy continues to grow, albeit mainly due to large-scale support measures from governments and regulators. Moreover, the latter are not sure about the prospects for such development, since the economies do not demonstrate the potential for independent growth. As a result, in order to stimulate it, regulators are forced to expand the range of their tools, mechanisms, approaches, otherwise the risks to the stability of the global financial and economic system increase. All this is happening against the background of negative rates, which have become virtually ubiquitous and persist for a long time. New growth records are being set in the stock markets, and their gap from the real economy is growing. A number of sectors are beginning to dominate, forming distortions and bubbles in the markets. In such conditions, the importance of digital money, ecosystems, etc. increases. Moreover, the faster and more efficiently regulators can integrate into these formats, the more successful business, the population, and the economy as a whole will be.

Highly Stable Ir-Ta-O Electrode for Ferroelectric Material Deposition

2000 ◽  
Vol 655 ◽  
Author(s):  
Fengyan Zhang ◽  
Sheng Teng Hsu ◽  
Jer-shen Maa ◽  
Yoshi Ono ◽  
Ying Hong ◽  
...  
Keyword(s):  
High Temperature ◽  
Bottom Electrode ◽  
Temperature Stability ◽  
Gate Oxide ◽  
Ferroelectric Material ◽  
High Temperature Stability ◽  
Material Deposition ◽  
Long Time ◽  
The Stability ◽  
Thin Gate Oxide

AbstractIr-Ta-O composite bottom electrode has extraordinary high temperature stability. It can maintain good conductivity and integrity even after 5min annealing at 1000 °C in oxygen ambient. The thermal stability of Ir-Ta-O on different substrates has been studied. It shows that Ir-Ta-O is also very stable on Si and SiO2 substrates. No hillock formation and peelings of the bottom electrode were observed after high temperature and long time annealing in O2 ambient. SEM, TEM, XRD, and AES have been used to characterize the Ir-Ta-O film and the interfaces between Ir-Ta-O bottom electrode and Si or SiO2 substrate. The composition and conductivity changes of the electrode during oxygen ambient annealing and the interdiffusion issue will be discussed. Furthermore, Ir-Ta-O/SiO2/Si capacitor with 30Å gate oxide was fabricated and the C-V and I-V characteristics were measured to confirm the stability of Ir-Ta-O on thin gate oxide.

scholarly journals A polyethersulfone–bisphenol sulfuric acid hollow fiber ultrafiltration membrane fabricated by a reverse thermally induced phase separation process

RSC Advances ◽  
2018 ◽  
Vol 8 (14) ◽  
pp. 7800-7809 ◽  
Author(s):  
Sheng-Hui Liu ◽  
Min Liu ◽  
Zhen-Liang Xu ◽  
Yong-Ming Wei
Keyword(s):  
Phase Separation ◽  
Sulfuric Acid ◽  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Ultrafiltration Membrane ◽  
Separation Process ◽  
Thermally Induced Phase Separation ◽  
Fiber Membrane ◽  
Thermally Induced ◽  
Phase Separation Process

A novel antifouling polyethersulfone (PES) hollow fiber membrane was modified by the addition of bisphenol sulfuric acid (BPA-PS) using a reverse thermally induced phase separation (RTIPS) process.

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