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Biomolecules ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 73
Author(s):  
Armin Mooranian ◽  
Corina Mihaela Ionescu ◽  
Daniel Walker ◽  
Melissa Jones ◽  
Susbin Raj Wagle ◽  
...  

Recent studies in our laboratories have shown promising effects of bile acids in ➀ drug encapsulation for oral targeted delivery (via capsule stabilization) particularly when encapsulated with Eudragit NM30D® and ➁ viable-cell encapsulation and delivery (via supporting cell viability and biological activities, postencapsulation). Accordingly, this study aimed to investigate applications of bile acid-Eudragit NM30D® capsules in viable-cell encapsulation ready for delivery. Mouse-cloned pancreatic β-cell line was cultured and cells encapsulated using bile acid-Eudragit NM30D® capsules, and capsules’ images, viability, inflammation, and bioenergetics of encapsulated cells assessed. The capsules’ thermal and chemical stability assays were also assessed to ascertain an association between capsules’ stability and cellular biological activities. Bile acid-Eudragit NM30D® capsules showed improved cell viability (e.g., F1 < F2 & F8; p < 0.05), insulin, inflammatory profile, and bioenergetics as well as thermal and chemical stability, compared with control. These effects were formulation-dependent and suggest, overall, that changes in ratios of bile acids to Eudragit NM30D® can change the microenvironment of the capsules and subsequent cellular biological activities.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Divya V. ◽  
Divya Jayan ◽  
Asoka Kumar

Purpose As there is a strong inducement to develop new colored inorganic materials to substitute the current industrial pigments that are based on toxic metals hazardous to health and the environment, the purpose of this paper is to invent environmentally benign rare earth-based colorants as viable alternatives to the traditional toxic pigment formulations. Herein, the authors developed a series of rare earth pigments having the general formula Ca0.1 Ln0.9 PO4 ( Ln = Y , Pr , mixed rare earth oxides, RE and Di). After studying all the optical properties, the authors have gone for some coloring application in plastic like PMMA. Design/methodology/approach The designed pigments were synthesized by traditional solid-state method. Stoichiometric amounts of each reagent were mixed in an agate mortar and the mixtures were calcined at optimized temperature 1000 °C for 4 h in electric furnace followed by auto–cooling. The samples were characterized by X-ray diffraction diffraction, UV–vis spectroscopy, scanning electron microscope (SEM), particle size distribution, color coordinates determination, acid/alkali test, thermo gravimetric (TG) analysis and CIE–1976 L*a*b* color scales. Among the various lanthanide ions and calcium ion as dopant, the pigment composition shows various hues ranges from green to yellow. The designed pigments consist of non–toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates like PMMA. Findings The present investigations establish that various color hues can be achieved by the incorporation of suitable chromophore metal ions like calcium in various rare earth host lattice by tuning of the band gaps. The coloring mechanism is based on the strong absorption of the pigments in the blue and red regions due to electronic transitions of the micro states of rare earth ion. The pigment composition shows various hues ranges from green to yellow. The coloring mechanism is based on the tuning of band gap by the dopant like calcium in various rare earth host lattice. In addition, this pigment was chemically and thermally stable. Finally, it has applied in plastics like PMMA. Research limitations/implications Mechanism of the color appearance using band calculations and on possible applications of rare earth phosphate powders as pigments in plastics and paints have not been explored much. However, the properties of the Ca-doped rare earth phosphate implies that this material has a potential to be applied as a satisfactory pigment for coating or coloring except for glaze, which may cause a side reaction at high temperatures, especially taking into consideration the economics and ecologies. The possibility of Ca2+ incorporation in CePO4 with monazite structure-type has been established. Practical implications The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications. Social implications There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. The designed pigments consist of non-toxic elements and were further found to possess high thermal and chemical stability. The pigments were also found to be appropriate candidates for the coloration of polymer substrates. Thus, the present environmental friendly pigment powders may find potential alternative to the classical toxic inorganic pigments for various applications. Originality/value There is a strong incentive to design new colorants based on inorganic materials to substitute for industrial pigments that are based on heavy elements hazardous to health and the environment. However, several industrial yellow pigments such as cadmium yellow (CdS), chrome yellow (PbCrO4) and nickel titanium yellow (TiO2-NiO-Sb2O3) contain the harmful elements (e.g. Cd, Pb, Cr and Sb) for the human body as well as the environment. So, the authors have developed new class of inorganic pigments that are both non-toxic and environmentally unimpeachable, while preserving or even exceeding the optical, thermal and chemical characteristics of the existing commercial pigments. The developed colorants find practical applications in polymer matrix like PMMA.


2021 ◽  
Vol 21 (9) ◽  
pp. 4675-4679
Author(s):  
Sunwoo Park ◽  
Yeonkyu Jeong ◽  
Seokwoo Kang ◽  
Sangshin Park ◽  
Hyukmin Kwon ◽  
...  

In this study, a triarylmethine derivative of DMCEBA-BTSA with the high thermal and chemical stability was newly synthesized in order to develop a high-performance image sensor. It showed a high transmittance of more than 80% at 450 nm and △Eab showed a very low color difference of 2.32 after thermal treatment. In solvent resistance, transmittance of 90% was not changed and △Eab showed a low color difference of 0.67 before and after solvent dipping. As a results of the migration test, there was no change at all after dipping in the PGMEA transmittance spectrum. It was confirmed that the newly synthesized blue colorant exhibited excellent thermal and chemical stability and it could be applied to image sensor color filter application as the blue color.


Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5294
Author(s):  
Alexey V. Bykov ◽  
Galina N. Demidenko ◽  
Linda Zh. Nikoshvili ◽  
Lioubov Kiwi-Minsker

Among different polymers nanostructured cross-linked aromatics have the greatest potential as catalytic supports due to their exceptional thermal and chemical stability and preservation of the active phase morphology. This work studies the ability of hyper-cross-linked polystyrene (HPS) to stabilize small Pdn and Ptn (n = 4 or 9) clusters. Unrestricted DFT calculations were carried out for benzene (BZ) adsorption at the BP level of theory using triple-zeta basis sets. The adsorption of BZ rings (stepwise from one to four) was found to result in noticeable gain in energy and stabilization of resulting adsorption complexes. Moreover, the interaction of metal clusters with HPS micropores was also addressed. For the first time, the incorporation of small clusters in the HPS structure was shown to influences its geometry resulting in the stabilization of polymer due to its partial relaxation.


2021 ◽  
pp. 1-12
Author(s):  
Robab Golzadeh ◽  
Mehrdad Mahkam ◽  
Ebrahim Rezaii ◽  
Leila Nazmi Miardan

Eutectic solvents (DES), have attracted much attention in the last decade. With the advantages of nonflammability, thermal and chemical stability, high solubility and partial vapor pressure, non-toxicity and reasonable prices, these solvents are suggested as useful solvents. On the other hand, the eutectic solvents developed by Abbott are the new generation of ionic liquids. The mixture of eutectics is from an ammonium salt and a hydrogen bonding compound such as urea, acid, amine, and non-toxic amines. Choline chloride and urea, are quite environmentally friendly and are known practically as green solvents. The purpose of the present research is to present the synthesis of diphenyl acetonitrile with 1-dimethylamino-2-chloropropane by a eutectic’s solvent. In addition, methadone is synthesized from the reaction of 2,2-Diphenyl-4-dimethylaminovaleronitrile with ethyl magnesium bromide in the presence of solvent eutectic, which is in optimal and environmentally compatible conditions and by principles of green chemistry.


2021 ◽  
Vol 21 (7) ◽  
pp. 3996-3999
Author(s):  
Sunwoo Park ◽  
Seokwoo Kang ◽  
Hokyeom Kim ◽  
Sanshin Park ◽  
Hyukmin Kwon ◽  
...  

In this study, a blue photoresist with the hybrid dye-pigment system was developed by mixing xanthene-based dye (XPDIA) and blue pigment 15:6 (1:1, 5 wt% of total mixture amount) in order to develop high-performance image sensors with high thermal and chemical stability. The colorant used in this study has the nano-sized particle of around 100 nm and the physical property is related with the photonic property in image sensor application such as the cameras of mobile phone, car black box, security, etc. The hybrid dye-pigment system showed a high transmittance of more than 90% at 450 nm, and Δab showed very low color difference of 0.52. In solvent resistance, high transmittance of 90% was perfectly maintained, and Δab showed low color difference of 1.08. Migration test result exhibited no change at all after dipping in PGMEA transmittance spectrum. These results are due to the high absorption optical properties of XPDIA dye in the HDPS and the high thermal and chemical stability properties of the PB15:6 pigment. As a result, it was confirmed that the mixed blue hybrid spin coating film exhibited excellent thermal and chemical stability as well as good optical property.


2021 ◽  
Vol 5 (6) ◽  
pp. 162
Author(s):  
Rasmeet Singh ◽  
Mandeep Singh ◽  
Nisha Kumari ◽  
Janak ◽  
Sthitapragyan Maharana ◽  
...  

Synthetic membranes are currently employed for multiple separation applications in various industries. They may have been prepared from organic or inorganic materials. Present research majorly focuses on polymeric (i.e., organic) membranes because they show better flexibility, pore formation mechanism, and thermal and chemical stability, and demand less area for installation. Dendritic, carbon nanotube, graphene and graphene oxide, metal and metal oxide, zwitter-ionic, and zeolite-based membranes are among the most promised water treatment membranes. This paper critically reviews the ongoing developments to utilize nanocomposite membranes to purify water. Various membranes have been reported to study their resistance and fouling properties. A special focus is given towards multiple ways in which these nanocomposite membranes can be employed. Therefore, this review provides a platform to develop the awareness of current research and motivate its readers to make further progress for utilizing nanocomposite membranes in water purification.


Author(s):  
A. Kumar

The current research on photocatalysis is totally focused on the designing and innovation of various low cost materials. For an efficient photocatalyst, there are some aspects which are to be assessed before practical use, such as optical activity, thermal and chemical stability, easy and availability of raw material, biocompatibility, etc. Fortunately, g-C3N4 offers most of these qualities to behave as a star photocatalyst. g-C3N4 could be easily prepared from low cost precursor materials such as urea, melamine, cyanimide and dicyandiamide by simple thermal treatment. Furthermore, larger surface area and two-dimensional planar conjugation structure of g-C3N4 can provide a large platform for anchoring various substrates. Various researchers have utilized g-C3N4 for varieties of applications such as green energy production, energy storage devices, biomedical application, wastewater treatment via photocatalysis and adsorption, photo sensors, etc. Although there are some disadvantages associated with use of g-C3N4 when utilized for various applications. To overcome such hitches various structural modifications have been applied to g-C3N4. The current chapter summarizes a wide mode of applications of g-C3N4 along with various structural modifications which were recently applied to improve the photocatalytic efficacy.


2021 ◽  
Author(s):  
Rahul Banerjee ◽  
Kalipada Koner ◽  
Shayan Karak ◽  
Sharath Kandambeth ◽  
Suvendu Karak ◽  
...  

Abstract Despite the noteworthy progress made in the nanotubular architectures with well-defined lengths and diameter, the synthesis of a purely covalent bonded organic nanotube, so far, proved to be elusive. Our work includes a hitherto unavailable structure, "Covalent Organic Nanotubes (CONTs)," to the repertoire. Strong covalent bonds between C, N, and O imparts high thermal and chemical stability of CONTs. This novel bottom-up approach provides an edge over the carbon nanotubes (CNTs) in functionalization, synthetic conditions, and porosity. CONT-1 exhibits a BET surface area of 321 m2g-1. These flexible CONTs intertwine with each other. The computational studies establish the role of solvent as the critical driving force for this type of convolution. Upon ultrasonication, the intertwined CONT-1 coil to form the toroidal superstructure.


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