Surface Microanalysis and Chemical Imaging of Early Dentin Remineralization

AbstractThis study reports physical and chemical changes that occur at early dentin remineralization stages. Extracted human third molars were sectioned to obtain dentin discs. After polishing the dentin surfaces, three groups were established: (1) untreated dentin (UD), (2) 37% phosphoric acid application for 15 s (partially demineralized dentin—PDD), and (3) 10% phosphoric acid for 12 h at 25° C (totally demineralized dentin—TDD). Five different remineralizing solutions were used: chlorhexidine (CHX), artificial saliva (AS), phosphate solution (PS), ZnCl2, and ZnO. Wettability (contact angle), ζ potential and Raman spectroscopy analysis were determined on dentin surfaces. Demineralization of dentin resulted in a higher contact angle. Wettability decreased after immersion in all solutions. ζ potential analysis showed dissimilar performance ranging from −6.21 mV (TDD + AS) up to 3.02 mV (PDD + PS). Raman analysis showed an increase in mineral components after immersing the dentin specimens, in terms of crystallinity, mineral content, and concentration. This confirmed the optimal incorporation and deposition of mineral on dentin collagen. Organic content reflected scarce changes, except in TDD that appeared partially denatured. Pyridinium, as an expression of cross-linking, appeared in all spectra except in specimens immersed in PS.

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Physical and chemical imaging of adhesive interfaces with soft X-rays

Communications Materials ◽

10.1038/s43246-021-00168-5 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Hiroyuki Yamane ◽

Masaki Oura ◽

Osamu Takahashi ◽

Tomoko Ishihara ◽

Noriko Yamazaki ◽

...

Keyword(s):

Molecular Level ◽

Covalent Bond ◽

Chemical Imaging ◽

Diglycidyl Ether ◽

X Rays ◽

X Ray ◽

Covalent Bond Formation ◽

Chemical States ◽

The Individual ◽

Physical And Chemical

AbstractAdhesion is an interfacial phenomenon that is critical for assembling carbon structural composites for next-generation aircraft and automobiles. However, there is limited understanding of adhesion on the molecular level because of the difficulty in revealing the individual bonding factors. Here, using soft X-ray spectromicroscopy we show the physical and chemical states of an adhesive interface composed of a thermosetting polymer of 4,4’-diaminodiphenylsulfone-cured bisphenol A diglycidyl ether adhered to a thermoplastic polymer of plasma-treated polyetheretherketone. We observe multiscale phenomena in the adhesion mechanisms, including sub-mm complex interface structure, sub-μm distribution of the functional groups, and molecular-level covalent-bond formation. These results provide a benchmark for further research to examine how physical and chemical states correlate with adhesion, and demonstrate that soft X-ray imaging is a promising approach for visualizing the physical and chemical states at adhesive interfaces from the sub-mm level to the molecular level.

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Physicochemical Characteristics of Arginine Enriched NaF Varnish: An In Vitro Study

Polymers ◽

10.3390/polym12122998 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2998

Author(s):

Mohammed Nadeem Bijle ◽

Manikandan Ekambaram ◽

Edward Lo ◽

Cynthia Yiu

Keyword(s):

Molecular Dynamics ◽

Physical Properties ◽

Artificial Saliva ◽

Chemical Properties ◽

In Vitro Study ◽

Physicochemical Characteristics ◽

Vitro Study ◽

Physical And Chemical ◽

Stable Matrix

The in vitro study objectives were to investigate the effect of arginine (Arg) incorporation in a 5% sodium fluoride (NaF) varnish on its physical and chemical properties including F/Arg release. Six experimental formulations were prepared with L-arginine (L-Arg) and L-arginine monohydrochloride at 2%, 4%, and 8% w/v in a 5% NaF varnish, which served as a control. The varnishes were subjected to assessments for adhesion, viscosity, and NaF extraction. Molecular dynamics were simulated to identify post-dynamics total energy for NaF=Arg/Arg>NaF/Arg<NaF concentrations. The Arg/F varnish release profiles were determined in polyacrylic lactate buffer (pH-4.5; 7 days) and artificial saliva (pH-7; 1 h, 24 h, and 12 weeks). Incorporation of L-Arg in NaF varnish significantly influences physical properties ameliorating retention (p < 0.001). L-Arg in NaF varnish institutes the Arg-F complex. Molecular dynamics suggests that NaF>Arg concentration denotes the stabilized environment compared to NaF<Arg (p < 0.001). The 2% Arg-NaF exhibits periodic perennial Arg/F release and shows significantly higher integrated mean F release than NaF (p < 0.001). Incorporating 2% L-arginine in 5% NaF varnish improves its physical properties and renders a stable matrix with enduring higher F/Arg release than control.

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Properties of Nano-Hybrid Sol-Gel Materials Synthesized from Colloidal Silica-Silane Containing Epoxy Silane

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2278 ◽

2007 ◽

Vol 336-338 ◽

pp. 2278-2281 ◽

Cited By ~ 2

Author(s):

Moon Kyong Na ◽

Dong Pil Kang ◽

Hoy Yul Park ◽

Myeong Sang Ahn ◽

In Hye Myung

Keyword(s):

Contact Angle ◽

Colloidal Silica ◽

Flat Surface ◽

Coating Layer ◽

Sol Gel ◽

Chemical Properties ◽

Coating Films ◽

Initial Stage ◽

Physical And Chemical ◽

And Chemical Properties

Three kinds of colloidal silica (CS)/silane sol solutions were synthesized in variation with parameters such as different acidity and reaction time. Sol solutions were prepared from HSA CS/ methyltrimethoxysilane (MTMS), LS CS/MTMS and LS CS/MTMS/γ -Glycidoxypropyltri methoxysilane (ES) solutions. In order to understand their physical and chemical properties, sol-gel coating films were fabricated on glass. Coating films on glass, obtained from LS/MTMS sol, had high contact angle, also, much enhanced flat surface in the case of LS/MTMS sol was observed in comparison with HSA/ MTMS sol. From all sol-gel solutions, seasoning effect of for enhancing properties of sol-gel coating layer on glass was observed while such sol-gel solutions were left for 7days. In initial stage of sol-gel reaction, all most of sol solutions used in this work seem to be unstable, formation of coating films was a little hazy and rough. However, improved coating films as observed in 4days later. LS/MTMS/ES sol solutions were synthesized with ES, adding to LS/MTMS sol. Contact angle of LS/MTMS/ES sol-gel coating films decreased, since ES played a role in forming hydrophilic hydroxyl sol. The elastic portion of coating films prepared from LS/MTMS/ES sol increased with addition of ES, but thermal stability decreased a little.

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Colloidal characteristics of gelatin-treated clay: Intercalation, stability, wettability, and rheological properties

Polymers and Polymer Composites ◽

10.1177/09673911211049111 ◽

2021 ◽

Vol 29 (9_suppl) ◽

pp. S1361-S1370

Author(s):

Xuwu Luo ◽

Guancheng Jiang ◽

Xinliang Li ◽

Lili Yang

Keyword(s):

Contact Angle ◽

Particle Size ◽

Rheological Properties ◽

Water Contact Angle ◽

X Ray Diffraction ◽

Sem Images ◽

Water Contact ◽

Ζ Potential ◽

And Behavior ◽

Clay Intercalation

In this paper, sodium montmorillonite was modified with gelatin of different concentrations, and various colloidal characteristics of the gelatin-treated clays were measured and analyzed in detail. First, the influence of gelatin on the interlayer space of Mt layers was investigated by X-ray diffraction analysis. Moreover, the aggregation of Mt particles was examined using a combination of electron microscopy and particle size distribution experiments, while the variation of the electrical property of Mt was measured using ζ potential test. Gelatin of different concentrations can increase the particle size of Mt in different degrees. The addition of 4% gelatin could improve the ζ potential of Mt from −30.65 to −15.55 mV. The wettability change of modified Mt induced by the adsorption of gelatin was followed by measurements of water contact angle and observations of the morphology of Mt/gelatin membrane through SEM images. 4% gelatin could improve the water contact angle of Mt to 81.3°. Finally, the rheological properties of Mt/gelatin dispersion including shear viscosity and shear stress were measured using a stress-controlled rheometer. All of the results were consistent by showing that the overall colloidal characteristics and behavior of the gelatin-treated Mt strongly varied depending on the gelatin concentration used in the modification process. These results can provide a deep and comprehensive understanding of the colloidal properties of clay/gelatin systems and give important guidance for the performance design and improvement of Mt/gelatin composite materials. Furthermore, this study can also be expanded the application of gelatin and its composites to other fields.

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Study on lignin-free lignocellulosic biomass and PSF-PEG membrane compatibility

BioResources ◽

10.15376/biores.16.1.1063-1075 ◽

2020 ◽

Vol 16 (1) ◽

pp. 1063-1075

Author(s):

Abiodun A. Amusa ◽

Abdul L. Ahmad ◽

Jimoh K. Adewole

Keyword(s):

Contact Angle ◽

Fourier Transform ◽

Infrared Spectroscopy ◽

Lignocellulosic Biomass ◽

Biomedical Applications ◽

Composite Membranes ◽

Hydroxyl Groups ◽

Chemical Pretreatment ◽

Physical And Chemical ◽

Porosity Measurements

Lignocellulosic biomass was delignified by combining physical and chemical pretreatment techniques. Then, a polysulfone-polyethylene glycol blend, which was compatible with the lignin-free biomass (0 wt% to 3.0 wt%), was used to fabricate composite membranes. The presence of hydroxyl groups after the pretreatment was evaluated via Fourier transform infrared spectroscopy. The rheology of the polymer solutions was assessed via the viscometric method. Also, the hydrophobicity of the fabricated membranes was determined using contact angle and porosity measurements. The fabricated membranes with near superhydrophobic properties (a contact angle of approximately 140°) based on this study revealed that contactor systems and biomedical applications would benefit from this modification.

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Experimental Determination of the Shale Wettability

10.5194/egusphere-egu2020-22681 ◽

2020 ◽

Author(s):

Aliya Mukhametdinova ◽

Natalia Bogdanovich ◽

Alexey Cheremisin ◽

Svetlana Rudakovskaya

Keyword(s):

Contact Angle ◽

Organic Content ◽

Wetting Angle ◽

Reservoir Rock ◽

Initial Assessment ◽

Reservoir Properties ◽

Laboratory Methods ◽

Thin Sections ◽

Mean Values ◽

Fluid Saturation

In recent years, the share of unconventional reserves in global oil production has grown. Exploration and development of unconventional resources require novel effective laboratory methods for characterizing the reservoir properties. The study and analysis of local shale deposits such as Bazhenov Formation (BF) in Western Siberia is a priority among non-traditional reservoirs. Wettability of the reservoir rock is one of the most important factors affecting the residual saturation and filtration properties in the formation. However, as multiple petrophysical studies show, conventional laboratory methods for characterizing the wettability are not applicable for this type of formations.In this work, the fluid saturation and wettability of BF rock samples were studied utilizing a nuclear magnetic resonance (NMR) and the method of determining the wetting contact angle by a surface drop. We have provided the petrographic description of rocks using ultrathin sections for grouping the samples. In addition, we used data on the organic content (TOC) obtained by the Rock-Eval method on a HAWK RW instrument (Wildcat Technologies) and the results of lithological typing on thin sections using an Axio Imager A2m polarizing microscope (Carl Zeiss) for detailed analysis of NMR and contact angle methods results.To assess wettability by NMR, T2 relaxation curves were constructed for extracted (cleaned), kerosene-saturated and water-saturated samples. A comparison of the relaxation spectra for kerosene and water enabled evaluation of the wettability for each by T2 log mean values. The calculation of the wetting angle was carried out for samples before and after the extraction, which revealed minor changes in the nature of the rock wettability because of cleaning. Thus, for this type of rock, the drop method for determining wettability turned out to be significantly sensitive to the shape of the OM distribution in the rock. Correlations built on wettability (by NMR results and calculated wetting angle) vs. TOC and lithotyping illustrated the dependence of rock wettability behavior on both the lithotype and the TOC content.The calculation of the wetting angle provided an initial assessment of the surface wettability of the rock and made it possible to establish the relationship between the wetting angle and the content of organic carbon (TOC), which is relevant for BF rocks. The lithological description of thin sections was used to highlight groups with a similar wettability of the rock. For the integral characteristics of the samples wettability, the NMR relaxometry method was proposed.

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Physical and Chemical Activation Effect on Activated Carbon Prepared from Local Pineapple Waste

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.699.87 ◽

2014 ◽

Vol 699 ◽

pp. 87-92 ◽

Cited By ~ 2

Author(s):

Abdul Rahim Yacob ◽

Adlina Azmi ◽

Mohd Khairul Asyraf Amat Mustajab

Keyword(s):

Activated Carbon ◽

Phosphoric Acid ◽

Surface Area ◽

Activated Carbons ◽

Chemical Activation ◽

Bet Surface Area ◽

Activation Effect ◽

Pineapple Waste ◽

Pineapple Peel ◽

Physical And Chemical

The characteristics and quality of activated carbons prepared depending on the chemical and physical properties of the starting materials and the activation method used. In this study, activated carbon prepared using pineapple waste. Three parts of pineapple waste which comprises of peel, crown and leaf were studied. For comparison activated carbon were prepared by both physical and chemical activation respectively. Three types of chemicals were used, phosphoric acid (H3PO4), sulphuric acid (H2SO4), and potassium hydroxide (KOH). The preparation includes carbonization at 200°C and activation at the 400°C using muffle furnace. The chemical characterization of the activated carbon was carried out using Thermogravimetric analysis (TGA), Nitrogen gas adsorption analysis and Fourier transform infrared (FTIR). The highest BET surface area was achieved when the pineapple peel soaked in 20% phosphoric acid with a surface area of 1115 m2g-1. FTIR analysis indicates that the reacted pineapple waste successfully converted into activated carbons.

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Surface Properties and MC3T3-E1 Cell Response of Cortical Bone Allografts Modified with Low-Concentration Phosphoric Acid

Cellular Physiology and Biochemistry ◽

10.1159/000470823 ◽

2017 ◽

Vol 41 (4) ◽

pp. 1572-1583 ◽

Cited By ~ 3

Author(s):

Zengfa Huang ◽

Cheng Cheng ◽

Jing Wang ◽

Hui Wei ◽

Xianzhe Liu ◽

...

Keyword(s):

Contact Angle ◽

Phosphoric Acid ◽

Western Blotting ◽

Animal Experiments ◽

Biomechanical Properties ◽

Potential Method ◽

Infection Model ◽

Low Concentration ◽

Model Studies ◽

Bone Allografts

Background/Aims: This experimental study aimed to evaluate the effect of low-concentration phosphoric acid on the surface structure of cortical allografts. Methods: Allogenic cortical bones were obtained from femurs and tibias of New Zealand white rabbits. The bones were modified by treatment with various concentrations of phosphoric acid (10%, 20% or 30%) for 10, 30 or 60 minutes, then evaluated by the following methods: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and LIVE/DEAD assay, alkaline phosphatase (ALP) assay, biomechanical properties testing, contact angle detection, quantitative real-time polymerase chain reaction (Q-PCR), western blotting and scanning electron microscopy (SEM). Results: Compared with the other groups, the group modified with 10% H3PO4 for 10 minutes had lower cytotoxicity according to MTT and LIVE/DEAD assays, higher hydrophilicity in the contact angle detection test and greater stability in the biomechanical properties test. Moreover, an up-regulation of osteopontin (OPN) in bones modified with 10% H3PO4 was observed by Q-PCR and western blotting. In addition, ALP assay and SEM showed that surface porosity and osteoinductivity were increased in the group modified with 10% H3PO4. Conclusions: Low-concentration phosphoric acid may be a potential method for surface modification of cortical allografts. Further animal experiments and animal infection model studies are required to validate the efficacy of surface-modified cortical allografts to repair large segmental bone defects.

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MEDIA ROOT TRAINER MENGANDUNG COCOPEAT DAN GAMBUT MENDUKUNG PERTUMBUHAN DAN KUALITAS AKAR BATANG BAWAH KARET / Root Trainer Media Containing Cocopeat and Peat to Support Growth and Quality of Rubber Rootstock Roots

Jurnal Penelitian Tanaman Industri ◽

10.21082/jlittri.v26n1.2020.23-31 ◽

2020 ◽

Vol 26 (1) ◽

pp. 23

Author(s):

Nur Eko Prasetyo ◽

Budi Setyawan ◽

Samijan Samijan ◽

Nofitri Dewi Rinojati ◽

Sumarmadji Sumarmadji

Keyword(s):

Plant Growth ◽

Block Design ◽

Chemical Properties ◽

Dry Weight ◽

Organic Content ◽

Exchange Capacity ◽

Duncan Multiple Range Test ◽

Randomized Block Design ◽

Physical And Chemical ◽

Range Test

The physical and chemical properties of the growing medium for root trainer of rubber are critical to support plant growth. This study aimed to obtain the best medium for growing rootstock rubber seedlings in the root trainer. Rubber clone PR 300 seeds were germinated for 21 days, then raised in root trainer pots for five months. The treatments evaluated were a mixture of cocopeat, Rawapening peat, and manure at different ratios. The experiment was designed in a Randomized Block Design, three replications, 30 plants per replicate, totaling 720 plants. The observed variables were N, P, K, Mg, C-organic content, pH, and cation exchange capacity of cocopeat, peat, and manure, as well as plant growth (height, stem diameter, wet weight, and dry weight). ANOVA used for analyzing data, followed with the Duncan Multiple Range Test at 5% level. The results showed that there were three best root trainer media for PR 300 rubber rootstock seedlings were a mixture of cocopeat + peat (1:1), cocopeat + peat + manure (1:2:1), and cocopeat + peat + manure (2:1:1). The growth and compactness of the roots are outstanding, so the seedlings are easily removed from the root trainer pots without significant damage. Based on the initiation and cost, the best root trainer medium is a mixture of cocopeat + peat + manure (1: 2:1). It is necessary to study the use of other types of peat soils apart from Rawapening. Also, it needs to be observed further plant growth after inoculation with the stem and after planting in the field.Keywords : Planting medium, Rawapening peat, rubber clone PR 300. Abstrak Sifat fisik dan kimia media tanam di dalam wadah root trainer bibit karet sangat penting untuk mendukung pertumbuhan tanaman. Penelitian ini bertujuan mendapatkan media terbaik untuk pertumbuhan bibit batang bawah karet di dalam root trainer. Benih klon karet PR 300 dikecambahkan selama 21 hari pada bedeng pengecambahan kemudian dipindah-tanam dan dibesarkan selama 5 bulan dalam pot root trainer. Perlakuannya yaitu campuran cocopeat, gambut Rawapening, dan pupuk kandang (pukan) pada berbagai ratio, dan kontrol. Penelitian dirancang secara Acak Kelompok, tiga ulangan, masing-masing 30 tanaman, sehingga totalnya 720 tanaman. Variabel yang diamati yaitu kandungan N, P, K, Mg, C-organik, pH, dan kapasitas tukar kation dari cocopeat, gambut, dan pupuk kandang, serta pertumbuhan tanaman (tinggi, diameter batang, bobot segar, dan bobot kering). Data dianalisis dengan ANOVA, kemudian Duncan Multiple Range Test pada taraf 5%. Hasil penelitian menunjukkan bahwa ada tiga macam media root trainer terbaik untuk bibit batang bawah karet klon PR 300 yaitu campuran cocopeat + gambut (1:1), cocopeat + gambut + pukan (1:2:1), dan cocopeat + gambut + pukan (2:1:1). Pertumbuhan dan kekompakan akar sangat baik sehingga bibit mudah dilepas dari root tainer tanpa kerusakan berarti. Berdasarkan kepraktisan dan biaya maka media root trainer terbaik adalah campuran media cocopeat + gambut + pukan (1:2:1). Perlu dilakukan kajian mengenai pemanfaatan tanah gambut jenis lainnya selain dari Rawapening. Selain itu, juga perlu diamati lebih lanjut pertumbuhan tanaman setelah diokulasi dengan batang atas maupun setelah ditanam di lapangan.Kata kunci : Gambut Rawapening, klon karet PR 300, media tanam.

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Long-term solubility and sorption characteristics of novel dental restoratives

International Journal of Engineering Science and Technology ◽

10.4314/ijest.v13i1.3s ◽

2021 ◽

Vol 13 (1) ◽

pp. 17-24

Author(s):

Sukriti Yadav ◽

Swati Gangwar

Keyword(s):

Artificial Saliva ◽

Dental Composite ◽

Dental Composites ◽

Distilled Water ◽

Structural Deterioration ◽

Dental Restoratives ◽

Physical And Chemical ◽

Dental Restorative ◽

Sorption Characteristics

Sorption and solubility are the unfavorable conditions for the dental restorative composites (DRCs). It can be precursor of various physical and chemical phenomenon that may lead to structural deterioration and minimizes the endurance of restorations. This study sought to evaluate the sorption and solubility features of MPTS (M)/APTES(A) treated n-HAPs filled dental composite in distilled water and artificial saliva medium. In this experiment, 7 different compositions of disc-shaped specimens of Φ15mm×1mm (n=3) of dental composites were prepared and tested under distilled water and artificial saliva medium for 35 days according to ISO 4049 method. The dental material shows relatively higher sorption and solubility in the artificial saliva medium as compared to distilled water. However, at higher wt.% (DRCs-12M & DRCs-12A), it shows minimum solubility (i.e.) and sorption characteristics. The results indicate that there was significant variation regarding storage medium and time to saturation but still these values are within the limit of the ISO 4049 standards, which is 40 μg/mm3 for sorption and 5μg/mm3 for Solubility.

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