Research of Suitable Material Pairs for Applications Operating with High WaterBased Fluids

Phenol–formaldehyde (PF) resin continues to dominate the resin industry more than 100 years after its first synthesis. Its versatile properties such as thermal stability, chemical resistance, fire resistance, and dimensional stability make it a suitable material for a wide range of applications. PF resins have been used in the wood industry as adhesives, in paints and coatings, and in the aerospace, construction, and building industries as composites and foams. Currently, petroleum is the key source of raw materials used in manufacturing PF resin. However, increasing environmental pollution and fossil fuel depletion have driven industries to seek sustainable alternatives to petroleum based raw materials. Over the past decade, researchers have replaced phenol and formaldehyde with sustainable materials such as lignin, tannin, cardanol, hydroxymethylfurfural, and glyoxal to produce bio-based PF resin. Several synthesis modifications are currently under investigation towards improving the properties of bio-based phenolic resin. This review discusses recent developments in the synthesis of PF resins, particularly those created from sustainable raw material substitutes, and modifications applied to the synthetic route in order to improve the mechanical properties.

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Recent Progress in the Development of Graphene Detector for Terahertz Detection

Sensors ◽

10.3390/s21154987 ◽

2021 ◽

Vol 21 (15) ◽

pp. 4987

Author(s):

Jianlong Liu ◽

Xin Li ◽

Ruirui Jiang ◽

Kaiqiang Yang ◽

Jing Zhao ◽

...

Keyword(s):

Recent Progress ◽

Photovoltaic Effect ◽

Dimensional Structure ◽

High Electron ◽

Terahertz Waves ◽

Terahertz Detectors ◽

Basic Part ◽

Suitable Material ◽

Terahertz Region ◽

Frequency Independent

Terahertz waves are expected to be used in next-generation communications, detection, and other fields due to their unique characteristics. As a basic part of the terahertz application system, the terahertz detector plays a key role in terahertz technology. Due to the two-dimensional structure, graphene has unique characteristics features, such as exceptionally high electron mobility, zero band-gap, and frequency-independent spectral absorption, particularly in the terahertz region, making it a suitable material for terahertz detectors. In this review, the recent progress of graphene terahertz detectors related to photovoltaic effect (PV), photothermoelectric effect (PTE), bolometric effect, and plasma wave resonance are introduced and discussed.

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Chemical stability of oil-infused polyethylene

Journal of Biomaterials Applications ◽

10.1177/0885328220977353 ◽

2020 ◽

pp. 088532822097735

Author(s):

Fedra P Zaribaf ◽

Harinderjit S Gill ◽

Elise C Pegg

Keyword(s):

Vitamin E ◽

Chemical Stability ◽

Antioxidant Properties ◽

Oxidation Stability ◽

Thermal Ageing ◽

Similar Process ◽

Mechanical Degradation ◽

Suitable Material ◽

Thermally Treated

Ultra-high molecular weight polyethylene (UHMWPE) can be made radiopaque for medical imaging applications through the diffusion of an iodised oil-based contrast agent (Lipiodol Ultra Fluid). A similar process is used for Vitamin E incorporated polyethylene which provides antioxidant properties. This study aimed to investigate the critical long-term properties of oil-infused medical polyethylene after 4 weeks of accelerated thermal ageing. Samples treated with an oil (Vitamin E or Lipiodol) had a higher oxidation stability than currently used medical grade polyethylene, indicated by a smaller increase in oxidation index after ageing (Vitamin E + 36%, Lipiodol +40%, Untreated +136%, Thermally treated +164%). The tensile properties of oil treated polyethylene after ageing were significantly higher than the Untreated and Thermally treated controls (p<0.05) indicating less mechanical degradation. There was also no alteration in the percentage crystallinity of oil treated samples after ageing, though the radiopacity of the Lipiodol treated samples reduced by 54% after ageing. The leaching of oil with time was also investigated; the leaching of Lipiodol and Vitamin E followed the same trend and reached a steady state by two weeks. Overall, it can be concluded that the diffusion of an oil-based fluid into polyethylene not only increases the oxidative and chemical stability of polyethylene but also adds additional functionality (e.g. radiopacity) providing a more suitable material for long–term medical applications.

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An approach using ddRADseq and machine learning for understanding speciation in Antarctic Antarctophilinidae gastropods

Scientific Reports ◽

10.1038/s41598-021-87244-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Juan Moles ◽

Shahan Derkarabetian ◽

Stefano Schiaparelli ◽

Michael Schrödl ◽

Jesús S. Troncoso ◽

...

Keyword(s):

Machine Learning ◽

Deep Sea ◽

Weddell Sea ◽

Nucleotide Polymorphisms ◽

Sea Levels ◽

Suitable Material ◽

Genetic Lineages ◽

Genome Wide ◽

Gastropod Mollusks ◽

Double Digestion

AbstractSampling impediments and paucity of suitable material for molecular analyses have precluded the study of speciation and radiation of deep-sea species in Antarctica. We analyzed barcodes together with genome-wide single nucleotide polymorphisms obtained from double digestion restriction site-associated DNA sequencing (ddRADseq) for species in the family Antarctophilinidae. We also reevaluated the fossil record associated with this taxon to provide further insights into the origin of the group. Novel approaches to identify distinctive genetic lineages, including unsupervised machine learning variational autoencoder plots, were used to establish species hypothesis frameworks. In this sense, three undescribed species and a complex of cryptic species were identified, suggesting allopatric speciation connected to geographic or bathymetric isolation. We further observed that the shallow waters around the Scotia Arc and on the continental shelf in the Weddell Sea present high endemism and diversity. In contrast, likely due to the glacial pressure during the Cenozoic, a deep-sea group with fewer species emerged expanding over great areas in the South-Atlantic Antarctic Ridge. Our study agrees on how diachronic paleoclimatic and current environmental factors shaped Antarctic communities both at the shallow and deep-sea levels, promoting Antarctica as the center of origin for numerous taxa such as gastropod mollusks.

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Sawdust for the Removal of Heavy Metals from Water: A Review

Molecules ◽

10.3390/molecules26144318 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4318

Author(s):

Elie Meez ◽

Abbas Rahdar ◽

George Z. Kyzas

Keyword(s):

Heavy Metals ◽

Adsorption Mechanism ◽

Freundlich Isotherm ◽

Order Kinetic ◽

Suitable Material ◽

Removal Of Heavy Metals ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

And Control ◽

Environmental Agencies

The threat of the accumulation of heavy metals in wastewater is increasing, due to their abilities to inflict damage to human health, especially in the past decade. The world’s environmental agencies are trying to issue several regulations that allow the management and control of random disposals of heavy metals. Scientific studies have heavily focused on finding suitable materials and techniques for the purification of wastewaters, but most solutions have been rejected due to cost-related issues. Several potential materials for this objective have been found and have been compared to determine the most suitable material for the purification process. Sawdust, among all the materials investigated, shows high potential and very promising results. Sawdust has been shown to have a good structure suitable for water purification processes. Parameters affecting the adsorption mechanism of heavy metals into sawdust have been studied and it has been shown that pH, contact time and several other parameters could play a major role in improving the adsorption process. The adsorption was found to follow the Langmuir or Freundlich isotherm and a pseudo second-order kinetic model, meaning that the type of adsorption was a chemisorption. Sawdust has major advantages to be considered and is one of the most promising materials to solve the wastewater problem.

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Electrospun PCL Patches with Controlled Fiber Morphology and Mechanical Performance for Skin Moisturization via Long-Term Release of Hemp Oil for Atopic Dermatitis

Membranes ◽

10.3390/membranes11010026 ◽

2020 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Sara Metwally ◽

Daniel P. Ura ◽

Zuzanna J. Krysiak ◽

Łukasz Kaniuk ◽

Piotr K. Szewczyk ◽

...

Keyword(s):

Mechanical Properties ◽

Atopic Dermatitis ◽

Mechanical Performance ◽

Antibacterial Properties ◽

Skin Condition ◽

Fiber Morphology ◽

Suitable Material ◽

Hemp Oil ◽

Skin Moisture

Atopic dermatitis (AD) is a chronic, inflammatory skin condition, caused by wide genetic, environmental, or immunologic factors. AD is very common in children but can occur at any age. The lack of long-term treatments forces the development of new strategies for skin regeneration. Polycaprolactone (PCL) is a well-developed, tissue-compatible biomaterial showing also good mechanical properties. In our study, we designed the electrospun PCL patches with controlled architecture and topography for long-term release in time. Hemp oil shows anti-inflammatory and antibacterial properties, increasing also the skin moisture without clogging the pores. It can be used as an alternative cure for patients that do not respond to traditional treatments. In the study, we tested the mechanical properties of PCL fibers, and the hemp oil spreading together with the release in time measured on skin model and human skin. The PCL membranes are suitable material as patches or bandages, characterized by good mechanical properties and high permeability. Importantly, PCL patches showed release of hemp oil up to 55% within 6 h, increasing also the skin moisture up to 25%. Our results confirmed that electrospun PCL patches are great material as oil carriers indicating a high potential to be used as skin patches for AD skin treatment.

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Creation of Ionically Crosslinked Tri-Layered Chitosan Membranes to Simulate Different Human Skin Properties

Materials ◽

10.3390/ma14071807 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1807

Author(s):

Rocío Guerle-Cavero ◽

Blanca Lleal-Fontàs ◽

Albert Balfagón-Costa

Keyword(s):

Elastic Modulus ◽

Human Skin ◽

Sodium Tripolyphosphate ◽

Snow Crab ◽

Suitable Material ◽

Cosmetic Industry ◽

Novel Method ◽

Current Article ◽

Chitosan Membranes

In 2023, new legislation will ban the use of animals in the cosmetic industry worldwide. This fact, together with ethical considerations concerning the use of animals or humans in scientific research, highlights the need to propose new alternatives for replacing their use. The aim of this study is to create a tri-layered chitosan membrane ionically crosslinked with sodium tripolyphosphate (TPP) in order to simulate the number of layers in human skin. The current article highlights the creation of a membrane where pores were induced by a novel method. Swelling index, pore creation, and mechanical property measurements revealed that the swelling index of chitosan membranes decreased and, their pore formation and elasticity increased with an increase in the Deacetylation Grade (DDA). Additionally, the results demonstrate that chitosan’s origin can influence the elastic modulus value and reproducibility, with higher values being obtained with seashell than snow crab or shrimp shells. Furthermore, the data show that the addition of each layer, until reaching three layers, increases the elastic modulus. Moreover, if layers are crosslinked, the elastic modulus increases to a much greater extent. The characterization of three kinds of chitosan membranes was performed to find the most suitable material for studying different human skin properties.

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Highly Effective Adsorption Process of Ni(II) Ions with the Use of Sewage Sludge Fly Ash Generated by Circulating Fluidized Bed Combustion (CFBC) Technology

Materials ◽

10.3390/ma14113106 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3106

Author(s):

Tomasz Kalak ◽

Kinga Marciszewicz ◽

Joanna Piepiórka-Stepuk

Keyword(s):

Fly Ash ◽

Sewage Sludge ◽

Fluidized Bed ◽

Circulating Fluidized Bed ◽

Municipal Sewage ◽

Municipal Sewage Sludge ◽

Fluidized Bed Combustion ◽

Nickel Ions ◽

Suitable Material ◽

Circulating Fluidized Bed Combustion

Recently, more and more attention has been paid to the removal of nickel ions due to their negative effects on the environment and human health. In this research, fly ash obtained as a result of incineration of municipal sewage sludge with the use of circulating fluidized bed combustion (CFBC) technology was used to analyze the possibility of removing Ni(II) ions in adsorption processes. The properties of the material were determined using analytical methods, such as SEM-EDS, XRD, BET, BJH, thermogravimetry, zeta potential, SEM, and FT-IR. Several factors were analyzed, such as adsorbent dose, initial pH, initial concentration, and contact time. As a result of the conducted research, the maximum sorption efficiency was obtained at the level of 99.9%. The kinetics analysis and isotherms showed that the pseudo-second order equation model and the Freundlich isotherm model best suited this process. In conclusion, sewage sludge fly ash may be a suitable material for the effective removal of nickel from wastewater and the improvement of water quality. This research is in line with current trends in the concepts of circular economy and sustainable development.

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Knowledge-Based System for Supporting the Design of a Plate-Press

Journal of Computing and Information Science in Engineering ◽

10.1115/1.4006444 ◽

2012 ◽

Vol 12 (2) ◽

Cited By ~ 12

Author(s):

David Potočnik ◽

Miran Ulbin ◽

Bojan Dolšak

Keyword(s):

Material Selection ◽

Compressive Load ◽

The Finite Element Method ◽

Design Quality ◽

Suitable Material ◽

Improve Design ◽

Knowledge Based System ◽

Cad System ◽

Design Time ◽

Knowledge Based

This paper presents a knowledge-based system capable of giving the designer quality support when making decisions from the aspect of modeling the reinforcement of a plate-press within a position of maximum compressive load, and by choosing suitable material for the plate. Based on the selected combination of reinforcement and material, this system acquaints the user with the size and position of the largest comparative stress, and the greatest nodal displacement in the load-direction. This system operates based on the implemented knowledge of experts in the execution of design, material selection, and numerical analysis based on the finite-element method (FEM), which was written with the help of parameters within the knowledge-base of the CATIA V5 CAD-system. Using this system gives the user an opportunity to reach conclusions that are crucial for designing a plate-press or pressure-loaded die-elements, in general. The results reveal that the system can dramatically shorten design time and improve design quality in comparison to manual design process.

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Discussion on Structural, Optical, Thermal, Mechanical, Dielectric and Third-Order NLO Properties of 3-Nitroanilinium Chloride Single Crystals for Optoelectronic Applications

10.21203/rs.3.rs-286274/v1 ◽

2021 ◽

Author(s):

C. S. JULIET BRINTHA ◽

S.E JOEMA

Keyword(s):

Single Crystal ◽

Mechanical Stability ◽

Damage Threshold ◽

Space Charge Polarization ◽

Laser Damage Threshold ◽

Closed Aperture ◽

Third Order ◽

Suitable Material ◽

Focusing Effect ◽

Optoelectronic Applications

Abstract Preferable, third-order nonlinear optical (NLO) single crystal, 3-Nitroanilinium chloride (3NACL) was auspiciously synthesised by slow evaporation technique. The crystal system of synthesised 3NACL crystal is triclinic with centrosymmetric space group was identified by single crystal XRD studies. All the functional groups present in the sample and its respective vibrations are analysed through FTIR analysis. UV-Vis transmittance spectrum revealed that the synthesised material was 83% transmittance and it cut-off wavelength was 276nm. The mechanical stability and thermal property of grown 3NACL crystals were ascertained by Vickers micro hardness analysis and TG/DTA analysis. The intermolecular interaction of the 3NACL was scrutinized by Hirshfeld surface analysis. Dielectric studies revealed that dielectric constant and dielectric loss were high at lower frequency region due to the space charge polarization. Inclusion free 3NACL crystal was used to analyse the Laser damage threshold (LDT) studies and its calculated LDT value was 4.3 GW/cm2. The third-order NLO parameters (β = 7.5472x10− 12 m/W, η2 = 5.6931x10− 19 m2/W, χ3 = 2.9491x10− 13 esu) of the 3NACL material was statutory evaluated by Z-scan studied. Here, β and η2 are positive value due to the saturated absorption and self-focusing effect was observed in open and closed aperture z-scan curve. Above all these findings 3NACL was suitable material for NLO and optoelectronic applications.

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