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Cancers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 5326
Author(s):  
Gabriela Schneider ◽  
Alagammai Kaliappan ◽  
Taylor Q. Nguyen ◽  
Robert Buscaglia ◽  
Guy N. Brock ◽  
...  

Early detection of lung cancer (LC) significantly increases the likelihood of successful treatment and improves LC survival rates. Currently, screening (mainly low-dose CT scans) is recommended for individuals at high risk. However, the recent increase in the number of LC cases unrelated to the well-known risk factors, and the high false-positive rate of low-dose CT, indicate a need to develop new, non-invasive methods for LC detection. Therefore, we evaluated the use of differential scanning calorimetry (DSC) for LC patients’ diagnosis and predicted survival. Additionally, by applying mass spectrometry, we investigated whether changes in O- and N-glycosylation of plasma proteins could be an underlying mechanism responsible for observed differences in DSC curves of LC and control subjects. Our results indicate selected DSC curve features could be useful for differentiation of LC patients from controls with some capable of distinction between subtypes and stages of LC. DSC curve features also correlate with LC patients’ overall/progression free survival. Moreover, the development of classification models combining patients’ DSC curves with selected plasma protein glycosylation levels that changed in the presence of LC could improve the sensitivity and specificity of the detection of LC. With further optimization and development of the classification method, DSC could provide an accurate, non-invasive, radiation-free strategy for LC screening and diagnosis.


Author(s):  
I. A. Saranov ◽  
O. B. Rudakov ◽  
K. K. Polansky ◽  
A. S. Ramazanov ◽  
S. A. Balaeva ◽  
...  

The method of differential scanning calorimetry (DSC) is used to characterize the thermophysical properties during melting of samples of milk thistle oil of various geographic origins, seeds and meal. The world experience in applying the DSC method on the study of milk thistle oils is generalized. The temperature measurement program is described. It is shown that, despite the general similarity of the curve profiles of the melting DSC, there are differences in the profiles due to genotypic and phenotypic factors - variety and growing location. The DSC curves of freshly squeezed oil distinguish from the DSC curves after 6 months storage of the oil due to oxidative deterioration and the formation of more refractory partially oxidized triacylglycerols. This fact is relevant to determining the capabilities of the DSC method in controlling the freshness of vegetable oils. The peaks amplitudes in the DSC curves of fresh oil are higher than those of oils that has been stored at room temperature for six months. Double differentiation of the melting curves makes it possible to reveal the temperatures of phase transitions in the case of overlapping endothermic peaks, the establishment of which is difficult without double differentiation. Using the «Netzsch Peak Separation» software to divide the peaks in the melting curves allows at once to estimate the areas of overlapping peaks and increase the informativeness of the DSC data. Thermal analysis of milk thistle seeds and meal reveals that the meal contains a residual amount of oil, in which the proportion of triunsaturated fats is overestimated in comparison to seeds, indicating that triunsaturated fats are more difficult to extract from oil by cold pressing.


2021 ◽  
Vol 11 (16) ◽  
pp. 7751
Author(s):  
Przemysław Talik ◽  
Aleksander Mendyk

Differently bound water molecules confined in hydrated hydroxypropyl cellulose (HPC) type MF and their mixtures (1:1 w/w) with lowly soluble salicylic acid and highly soluble sodium salicylate were investigated by differential scanning calorimetry (DSC). The obtained ice-melting DSC curves of the HPC/H2O samples were deconvoluted into multiple components, using a specially developed curve decomposition tool. The ice-melting enthalpies of the individual deconvoluted components were used to estimate the amounts of water in three states in the HPC matrix: free water (FW), freezing bound water (FBW), and non-freezing water (NFW). A search for an optimal number of Gaussian functions was carried out among all available samples of data and was based on the analysis of the minimum fitting error vs. the number of Gaussians. Finally, three Gaussians accounting for three fractions of water were chosen for further analysis. The results of the calculations are discussed in detail and compared to previously obtained experimental DSC data. AI/ML tools assisted in theory elaboration and indirect validation of the hypothetical mechanism of the interaction of water with the HPC polymer.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 820
Author(s):  
Angela Abruzzo ◽  
Carola Parolin ◽  
Elisa Corazza ◽  
Barbara Giordani ◽  
Massimiliano Pio di Cagno ◽  
...  

One of the most widely used strategies to improve drug diffusion through the skin is the use of permeation enhancers. The aim of this work was to investigate the effect of two biosurfactants (BS), produced by Lactobacillus crispatus BC1 and Lactobacillus gasseri BC9, on the skin permeation profile of hydrocortisone (HC, model drug). HC aqueous solubility and in vitro diffusion studies through porcine skin were performed in the presence of BC1-BS and BC9-BS at concentrations below and above critical micellar concentrations (CMC). Moreover, skin hydration tests and differential scanning calorimetry (DSC) analysis were performed to further investigate BS interaction with the outermost layer of the skin. Both BS increased HC solubility, especially at concentrations above their CMC. At concentrations below the CMC, drug permeation through the skin was improved, as the result of a dual effect: a) the formation of a superficial lipophilic environment, as confirmed by the reduction in skin hydration and b) the interaction between BS and the stratum corneum (SC), as demonstrated by the DSC curves. From the obtained data, it appears that BC1-BS and BC9-BS could represent new promising green excipients for drug permeation enhancement through the skin.


2021 ◽  
Author(s):  
Swati Ravindra Korgaonkar ◽  
Usha Sayed

Abstract Egg shell are considered as waste and are generally dumped in the landfills. As the world is moving towards the sustainable way to recycle the waste and hence adding value to the waste produced. The egg shell is consisting of essential amino acids and properties which are still unexploited in various textile processing. The egg shell has proteineous matter which makes it a natural flame retardant. Cotton is the majorly used fibre in the overall textile industry. In the present study the egg shell waste was used to prepare an extract which is further applied on cotton fabric as a flame retardant. The characterization of the above egg shell powder shows it has amine group present at 1072.6 as well as at 873.56cm - C-Cl halo compound is present confirmed through FT-IR analysis. Two peaks were observed in DSC curves at 224.4 0 C and 254.5 °C. A LoI of cotton has increased to 36 at a lower concentration of 30% while that compared with the conventional cotton fabric.


2021 ◽  
pp. 095400832199674
Author(s):  
Tao Guo ◽  
Yang Fan ◽  
Chang Bo ◽  
Zhang Qi ◽  
Han Tao ◽  
...  

Benzoxazine resin exhibits excellent properties and is widely used in many fields. Herein, the synthesis of a novel compound, the bis(2,4-dihydro-2 H-3-(4- N-maleimido)phenyl-1,3-benzoxazinyl)biphenyl (BMIPBB), has been reported, which was synthesized by reacting N-(4-aminophenyl)maleimide (APMI), formaldehyde, and 4,4’-dihydroxybiphenyl. 1,3,5-three(4-(maleimido)phenyl)-1,3,5-triazine (TMIPT) was formed as an intermediate during the reaction. The proton nuclear magnetic resonance (1H-NMR) and Fourier transform-infrared (FTIR) spectroscopy experiments were conducted to determine the structure of BMIPBB. BMIPBB was obtained as a reddish-brown solid in 40.1% yield. The thermal properties of BMIPBB were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. Analysis of the DSC curves revealed that the broad peak representing the release of curing reaction heat appeared in the temperature range of 140–330°C. The peak temperature was 242.59°C and the heat of the reaction was 393.82 J/g, indicating that the rate of the curing reaction was low and the heat of the reaction was high. Analysis of the TGA results revealed that the weight loss rate was 5% at 110°C. The monomer exhibited a significant weight loss in the range of 320–500°C. The compound lost 50% of its weight at a temperature of 427°C.


2021 ◽  
Vol 26 (3) ◽  
Author(s):  
Priscila Marques Correa ◽  
Diego Guimarães ◽  
Ruth Marlene Campomanes Santana ◽  
Ângela Gaio Graeff

ABSTRACT The use of polymeric residues in the civil construction has been the target of many studies aiming to reduce the volume of post-consumer plastics in the environment. This work focuses on the viability to use polyethylene terephthalate (PET) and polypropylene (PP) as partial replacement to sand in concrete. PET and PP flakes from post-consumer packings were used as light aggregate to partially replace, individually, 10% in volume of sand. The effect of adding these polymers was investigated in terms of physical, mechanical, durability and morphological properties of the concrete. Physical properties were measured in terms of water absorption, voids content and specific mass. Mechanical properties were measured in terms of compressive strength and elasticity modulus. Durability properties were measured in terms of capillarity water absorption and electrical indication of the concrete to resist to chloride ion penetration. MEV and EDS were used to carry out morphological analysis. DSC curves were carried out to evaluate thermal properties of the polymeric flakes. Contact anlge test was also performed. The partial addition of PET and PP polymers reduced the compressive strength by 20%, whilst the reduction of the elasticity modulus was 16% for PET samples, and almost insignificant for PP samples. The durability results show that the polymers contributed to increase the resistance of the samples to chloride penetration by 15% and 57%, for PET and PP samples, respectively; however, there was an increase in the voids content and water absorption. In the morphological test it is possible to observe a lower interfacial adhesion between PP and the cementions paste in comparison to PET.


2020 ◽  
Vol 65 (1) ◽  
pp. 76-85
Author(s):  
Indri Dayana ◽  
Anggito P. Tetuko ◽  
Timbangen Sembiring ◽  
Kurnia Sembiring ◽  
Nining S. Asri ◽  
...  

The magnetite (Fe3O4) particles that have been coated using tetraethyl orthosilicate (TEOS) as silica precursors were used as the additive in the lubricant. The effects of silica-coated magnetite additive on the thermal properties of ferro-lubricant and reducing the friction on a steel plate have been investigated. The characterizations were conducted at both conditions: with and without the addition of Fe3O4 particles. The characterization using TEM proposed that the average particle size of the silica-coated magnetite particles is 150 nm. The TGA/DSC curves of the silica-coated magnetite particles suggested a gradual weight loss obtained as the temperature increased. The endothermic peak was obtained at ~37 and 50 °C. The silica-coated magnetite particles’ additive increases both the density and viscosity of 0.84 g/cm3 and 134.29 cSt. The silica-coated magnetite particles additive in the lubricant enhances the thermal conductivity and specific heat of 0.151 W/m.K and 1600 J/kg.K. Ferro-lubricant reduces the friction coefficient up to 0.02 (static) and 0.005 (dynamic). The wear resistance of the plate could be improved as analyzed using an optical microscope. These results demonstrate a promising application of the silica-coated magnetite particles as an additive in the lubricant. Therefore improving wear resistance and cooling during the friction process.


2020 ◽  
Author(s):  
Maria Sonmez ◽  
Mircea Juganaru ◽  
Anton Ficai ◽  
Ovidiu Oprea ◽  
Roxana Trusca ◽  
...  

The aim of this paper was to assess the influence of the modification of the surface of dolomite and kaolin with SiO2 and TiO2 precursors, on the block copolymer styrene-butadiene-styrene (SBS) type thermoplastic rubber properties. These composite materials were obtained by compounding SBS with various ratio of powders. Based on the SEM images it can conclude that the powders were homogenously dispersed in to the SBS matrix. The dolomite particles can be clearly identified in the SEM images as particles of 10 micrometers. The samples obtained with modified dolomite have similar morphology. The EDS elemental distribution confirming a good corroboration between the elements of the dolomite, kaolin and titanium or silicon elements. Based on the thermal analysis according to the residual mass, the presence of 20% mineral phase can be confirmed. According to the DSC curves a strong stabilization of the composite appears, because of the presence of the mineral component. According to the physical-mechanical data all the composite materials exhibit improved mechanical properties. Additionally, the modification of the kaolin and/or dolomite bring important improvements in mechanical properties. The samples 13 and 14 exhibit high tensile and tear strength. These composites can be used for various applications, such as, for instance, soles for firefighters' footwear.


Author(s):  
Anikó Kovács ◽  
Katalin Badakné Kerti ◽  
László Somogyi

AbstractExcessive consumption of added sugar is associated with many health problems, for example obesity, type 2 diabetes, etc. Hence there is an urgent need for the product reformulation by total replacement or partial reduction of sugar in food industry. The aim of this research was to study the effect of sugar substitution (by stevia and xylitol) on model confectionary systems. We investigated differences in the texture properties, the viscosity and thermal properties of the blends. Based on our results, the sugar substitution affects the physical properties of the measured samples. The apparent viscosity and the texture properties were changed due to the different dry matter content in the samples. In the differential scanning calorimeter (DSC) curves the different melting of the samples were expressed according to the changes in sugar content. Further work is needed in this field to follow up the discovered changes in thermal behaviour of these mixtures.


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