scholarly journals Nanofibrillar Green Composites of Polylactide/Polyhydroxyalkanoate Produced in Situ Due to Shear Induced Crystallization

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1811 ◽  
Author(s):  
Iurii Vozniak ◽  
Ramin Hosseinnezhad ◽  
Jerzy Morawiec ◽  
Andrzej Galeski
Keyword(s):  
Single Step ◽  
Polymer Fibers ◽  
Simultaneous Occurrence ◽  
Simultaneous Increase ◽  
High Shear ◽  
Molten State ◽  
Brittle To Ductile Transition ◽  
Fibrillar Morphology ◽  
Induced Crystallization

This study addresses the new concept of in situ inducing fibrillar morphology (micro or nanofibrils) of a minority component based on the simultaneous occurrence of orientation and shear induced crystallization of polymer fibers directly at the stage of extrusion in a single step. This possibility is demonstrated by using two entirely bio-sourced polymers: polylactide (PLA) and polyhydroxyalkanoate (PHA) as components. The shear induced crystallization allowed crystallization of PHA nanofibers immediately after applying high shear rate and elongation strain, avoiding subsequent cooling to initiate crystallization. Shearing of PHA increased non-isothermal crystallization temperature by 50 °C and decreased the temperature range in which the transition from a molten state to a crystallized one occurs by 17 °C. SEM observations demonstrate the successful transformation of the dispersed PHA phase into nanofibrils with diameters of nearly 200 nm. The transition from the droplets of PHA to fibers causes the brittle-to-ductile transition of the PLA matrix at a low concentration of PHA and contributes to the simultaneous increase of its rigidity and strength.

scholarly journals Single Step In Situ Detection of Surface Protein and MicroRNA in Clustered Extracellular Vesicles Using Flow Cytometry

2021 ◽  
Vol 10 (2) ◽  
pp. 319
Author(s):  
Hee Cheol Yang ◽  
Won Jong Rhee
Keyword(s):  
Extracellular Vesicles ◽  
Liquid Biopsy ◽  
Molecular Beacon ◽  
Disease Diagnosis ◽  
Single Step ◽  
Flow Cytometer ◽  
Surface Proteins ◽  
Biomarker Detection ◽  
In Situ Detection

Because cancers are heterogeneous, it is evident that multiplexed detection is required to achieve disease diagnosis with high accuracy and specificity. Extracellular vesicles (EVs) have been a subject of great interest as sources of novel biomarkers for cancer liquid biopsy. However, EVs are nano-sized particles that are difficult to handle; thus, it is necessary to develop a method that enables efficient and straightforward EV biomarker detection. In the present study, we developed a method for single step in situ detection of EV surface proteins and inner miRNAs simultaneously using a flow cytometer. CD63 antibody and molecular beacon-21 were investigated for multiplexed biomarker detection in normal and cancer EVs. A phospholipid-polymer-phospholipid conjugate was introduced to induce clustering of the EVs analyzed using nanoparticle tracking analysis, which enhanced the detection signals. As a result, the method could detect and distinguish cancer cell-derived EVs using a flow cytometer. Thus, single step in situ detection of multiple EV biomarkers using a flow cytometer can be applied as a simple, labor- and time-saving, non-invasive liquid biopsy for the diagnosis of various diseases, including cancer.

scholarly journals Computational and experimental investigations of one-step conversion of poly(carbonate)s into value-added poly(aryl ether sulfone)s

2016 ◽  
Vol 113 (28) ◽  
pp. 7722-7726 ◽  
Author(s):  
Gavin O. Jones ◽  
Alexander Yuen ◽  
Rudy J. Wojtecki ◽  
James L. Hedrick ◽  
Jeannette M. García
Keyword(s):  
High Performance ◽  
Density Functional ◽  
Value Added ◽  
Single Step ◽  
Nucleophilic Attack ◽  
Experimental Investigations ◽  
Aryl Ether ◽  
One Step ◽  
Poly Carbonate

It is estimated that ∼2.7 million tons poly(carbonate)s (PCs) are produced annually worldwide. In 2008, retailers pulled products from store shelves after reports of bisphenol A (BPA) leaching from baby bottles, reusable drink bottles, and other retail products. Since PCs are not typically recycled, a need for the repurposing of the PC waste has arisen. We report the one-step synthesis of poly(aryl ether sulfone)s (PSUs) from the depolymerization of PCs and in situ polycondensation with bis(aryl fluorides) in the presence of carbonate salts. PSUs are high-performance engineering thermoplastics that are commonly used for reverse osmosis and water purification membranes, medical equipment, as well as high temperature applications. PSUs generated through this cascade approach were isolated in high purity and yield with the expected thermal properties and represent a procedure for direct conversion of one class of polymer to another in a single step. Computational investigations performed with density functional theory predict that the carbonate salt plays two important catalytic roles in this reaction: it decomposes the PCs by nucleophilic attack, and in the subsequent polyether formation process, it promotes the reaction of phenolate dimers formed in situ with the aryl fluorides present. We envision repurposing poly(BPA carbonate) for the production of value-added polymers.

In-situ He+ irradiation induced crystallization on crystalline/amorphous ZrC films

2021 ◽  
pp. 102580
Author(s):  
Shengming Jiang ◽  
Ruihua Zhu ◽  
Ming Chen ◽  
Huanhuan He ◽  
Zhiwei Lin ◽  
...  
Keyword(s):  
Induced Crystallization

Stretch-Induced Crystallization and Phase Transitions of Poly(dimethylsiloxane) at Low Temperatures: An in Situ Synchrotron Radiation Wide-Angle X-ray Scattering Study

2018 ◽  
Vol 51 (21) ◽  
pp. 8424-8434 ◽  
Author(s):  
Jingyun Zhao ◽  
Pinzhang Chen ◽  
Yuanfei Lin ◽  
Jiarui Chang ◽  
Ai Lu ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Synchrotron Radiation ◽  
Low Temperatures ◽  
Wide Angle ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Study ◽  
Induced Crystallization ◽  
Ray Scattering

Preparation of the polymerizable titania oriented to 3D printing and the laser-induced crystallization

2018 ◽  
Vol 24 (9) ◽  
pp. 1421-1427 ◽  
Author(s):  
Feng Liu ◽  
Shaoai Xie ◽  
Yan Wang ◽  
Jianjun Yu ◽  
Qinghua Meng
Keyword(s):  
3D Printing ◽  
Sol Gel ◽  
Crystal Form ◽  
Tetrabutyl Titanate ◽  
Content Type ◽  
Functional Additives ◽  
Sol Gel Process ◽  
Photosensitive Resin ◽  
Induced Crystallization

PurposeThe titania (titanium dioxide) is one of the important functional additives in the photosensitive resin and encounters the problem of stabilization in the photosensitive resin for 3D printing. This study aims to achieve enhancement in stabilization by preparation of the polymerizable titania andin situlaser-induced crystallization during 3D printing.Design/methodology/approachA type of polymerizable titania (AAEM@TiO2) was designed and prepared from tetrabutyl titanate (TBT) and 2-(acetoacetoxy)ethyl methacrylate (AAEM) via the sol–gel process, which was characterized by Fourier-transform infrared (FTIR) spectra, ultraviolet–visible (UV-Vis) spectra, surface bonding efficiency (SBE) and settling height (H). AAEM acted on both bonding to the titania and polymerization with the monomer in resin for stabilization. The polymerizable titania could be converted to the pigmented titania by means of laser-induced crystallization. The photosensitive resin was then formulated on the basis of optimization and used in a stereolithography apparatus (SLA) for 3D printing.FindingsThe stabilization effect of AAEM on TiO2was achieved and the mechanism of competition in the light-consuming reactions during photocuring was proposed. The ratio of nAAEM/nTBTin AAEM@TiO2, the concentration of AAEM@TiO2and photoinitiator (PI) used in the photosensitive resin were optimized. The anatase crystal form was indicated by X-ray diffraction (XRD) and clustering of nanocrystals was revealed by scanning electron microscopy (SEM) after SLA 3D printing.Originality/valueThis investigation provides a novel method of pigmentation by preparation of the polymerizable titania andin situlaser-induced crystallization for SLA 3D printing.

In-situ single-step electrochemical AgO modified graphite pencil electrode for trace determination of DL-methionine in human serum sample

2019 ◽  
Vol 281 ◽  
pp. 765-773 ◽  
Author(s):  
Nurudeen A. Odewunmi ◽  
Abdel-Nasser Kawde ◽  
Mohamed Ibrahim
Keyword(s):  
Human Serum ◽  
Serum Sample ◽  
Single Step ◽  
Trace Determination ◽  
Human Serum Sample

scholarly journals Monosomy 12 and deletion of 13q34 in a case of chronic lymphocytic leukemia with concomitant lung cancer

2010 ◽  
Vol 67 (10) ◽  
pp. 864-866 ◽  
Author(s):  
Darko Antic ◽  
Marija Dencic-Fekete ◽  
Dragica Tomin ◽  
Irena Djunic
Keyword(s):  
Lung Cancer ◽  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Lung Carcinoma ◽  
Prognostic Significance ◽  
Specific Treatment ◽  
Lymphocytic Leukemia ◽  
Simultaneous Occurrence ◽  
Hybridization Technique

Background. We described a patient with chronic lymphocytic leukemia (CLL) and lung cancer and unusual chromosomal aberrations. Case report. At the same time with the diagnosis of B-cell CLL, squamocellular lung carcinoma diagnosis was established. Using interphase fluoresecence in situ hybridization technique (FISH) we detected monosomy 12 and deletion of 13q34 occured in the same clone. One month after the beginning of examination the patient died unexpectedly during sleep immediately before we applied a specific treatment for CLL or lung carcinoma. Conclusion. Simultaneous occurrence of monosomy 12 and deletion of 13q34 in a patient with B-cell CLL has been described only once before, but as a part of a complex karyotype. The prognostic significance of these abnormalities remains uncertain.

scholarly journals Hydrophobic Starch-Based Films Using Potato Washing Slurries and Spent Frying Oil

Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2897
Author(s):  
Sílvia Petronilho ◽  
André Oliveira ◽  
M. Rosário Domingues ◽  
Fernando M. Nunes ◽  
Manuel A. Coimbra ◽  
...  
Keyword(s):  
Potato Starch ◽  
Contact Angles ◽  
Single Step ◽  
Frying Oil ◽  
Biodegradable Films ◽  
Water Contact ◽  
Alkaline Catalyst ◽  
Application Range ◽  
Structural Differences

Starch is a promising candidate for preparing biodegradable films with useful gas barriers and thermoplastic capabilities. However, these materials are hydrophilic and brittle, thus limiting their application range. To overcome these drawbacks, it has been hypothesized that starch can be hydrophobized and plasticized during the starch-based film production using a single-step approach and following transesterification principles. In this work, KOH powder and spent frying oil (SFO) were used as an alkaline catalyst and a source for triacylglycerides, respectively, to promote the modification of starch. Different ratios of SFO (w/w related to the dried starch weight) were tested. When compared to the neat films (without a catalyst and SFO), the incorporation of at least 15% SFO/KOH gave rise to transparent, hydrophobic (water contact angles of ca. 90°), stretchable (ca. 20×), elastic (ca. 5×), and water tolerant starch-based films, contrary to the films produced without the catalyst. ATR-FTIR and 1H NMR revealed structural differences among the produced films, suggesting that starch was modified with the SFO-derived fatty acids. Therefore, adding KOH during the potato starch/spent frying oil-based film’s production was determined to be a promising in situ strategy to develop starch-based materials with improved hydrophobicity and flexibility, while valorizing the potato chip industry’s byproducts.

scholarly journals Correlating work hardening with co-activation of stacking fault strengthening and transformation in a high entropy alloy using in-situ neutron diffraction

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. Frank ◽  
S. S. Nene ◽  
Y. Chen ◽  
B. Gwalani ◽  
E. J. Kautz ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Work Hardening ◽  
Dislocation Motion ◽  
Stacking Fault ◽  
Dislocation Slip ◽  
Simultaneous Increase ◽  
High Entropy Alloy ◽  
High Entropy ◽  
In Situ Neutron Diffraction

AbstractTransformation induced plasticity (TRIP) leads to enhancements in ductility in low stacking fault energy (SFE) alloys, however to achieve an unconventional increase in strength simultaneously, there must be barriers to dislocation motion. While stacking faults (SFs) contribute to strengthening by impeding dislocation motion, the contribution of SF strengthening to work hardening during deformation is not well understood; as compared to dislocation slip, twinning induced plasticity (TWIP) and TRIP. Thus, we used in-situ neutron diffraction to correlate SF strengthening to work hardening behavior in a low SFE Fe40Mn20Cr15Co20Si5 (at%) high entropy alloy, SFE ~ 6.31 mJ m−2. Cooperative activation of multiple mechanisms was indicated by increases in SF strengthening and γ-f.c.c. → ε-h.c.p. transformation leading to a simultaneous increase in strength and ductility. The present study demonstrates the application of in-situ, neutron or X-ray, diffraction techniques to correlating SF strengthening to work hardening.

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