Two efficient blue thermally activated delayed fluorescence compounds, B‐oCz and B‐oTC, composed of ortho‐donor (D)–acceptor (A) arrangement were designed and synthesized. The significant ...intramolecular D–A interactions induce a combined charge transfer pathway and thus achieve small ΔEST and high efficiencies. The concentration quenching can be effectively inhibited in films of these compounds. The blue non‐doped organic light emitting diodes (OLEDs) based on B‐oTC prepared from solution processes shows record‐high external quantum efficiency (EQE) of 19.1 %.
Blue note: Highly efficient blue thermally activated delayed fluorescent (TADF) materials have been developed by using a new design strategy. Solution‐processed, non‐doped blue organic light‐emitting diodes based on these emitters realized record‐high external quantum efficiency of 19.1 %.
•Waxy wheat starch treated with HHP of 600MPa had the maximum SDS content of 31.12%.•HHPR treatment decreased gelatinization temperatures of waxy wheat starch.•HHPR treatment decreased gelatinization ...enthalpy of waxy wheat starch.•HHPR treatment decreased relative crystallinity and peak viscosity of waxy wheat starch.•HHPR treatment destroyed the structure of waxy wheat starch granules.
In this study, the effects of high hydrostatic pressure and retrogradation (HHPR) treatments on in vitro digestibility, structural and physicochemical properties of waxy wheat starch were investigated. The waxy wheat starch slurries (10%, w/v) were treated with high hydrostatic pressures of 300, 400, 500, 600MPa at 20°C for 30min, respectively, and then retrograded at 4°C for 4d. The results indicated that the content of slowly digestible starch (SDS) in HHPR-treated starch samples increased with increasing pressure level, and it reached the maximum (31.12%) at 600MPa. HHPR treatment decreased the gelatinization temperatures, the gelatinization enthalpy, the relative crystallinity and the peak viscosity of the starch samples. Moreover, HHPR treatment destroyed the surface and interior structures of starch granules. These results suggest that the in vitro digestibility, physicochemical, and structural properties of waxy wheat starch are effectively modified by HHPR.
In the present study, the effects of repeated heat-moisture treatments (RHMT) on the in vitro digestibility, physicochemical and structural properties of sweet potato starch were investigated. The ...cycling times of RHMT ranging from 1 to 5 and heat-moisture treatment for 6 h were designated as RHMT-1, RHMT-2, RHMT-3, RHMT-4, RHMT-5 and HMT-6h, respectively. The results showed that as the cycling times of RHMT increased, the SDS content of starch samples increased gradually and reached the maximum (19.61%) by RHMT for 3 times, and the thermo-stable SDS content also increased and reached the maximum (14.46%) by RHMT-3, while the swelling power and solubility decreased gradually. Compared with the native starch, the gelatinization transition temperatures of modified starch samples were significantly increased, gelatinization enthalpy and gelatinization temperature range decreased markedly. The values of degree of gelatinization (DG) showed that RHMT caused some gelatinization of the starch granules. Moreover, the RHMT starch samples exhibited significantly increased pasting temperatures, reduced viscosities, and no longer exhibited traditional pasting profiles for the lack of a true peak viscosity and no breakdown, and the agglomerations of granules were found in them. The variation in infrared absorbance ratio of 1047 cm−1 and 1022 cm−1 of RHMT starch samples were consistent with that in relative crystallinity, and RHMT starch samples exhibited A type crystalline pattern. These results suggested that structural changes of sweet potato starch by RHMT significantly affected the digestibility and physicochemical properties.
Display omitted
•Sweet potato starch was modified by repeated heat-moisture treatments (RHMT).•The RHMT-3 starch samples had the maximum SDS content of 19.61%.•Thermo-stable SDS content reached the maximum (14.46%) by RHMT-3.•Thermal and pasting properties were significantly changed by RHMT.•RHMT changed the crystalline pattern from Ca to A type.
•Two main pyrolysis stage of waste bicycle tire can be observed from TG.•The release characteristics of volatiles was consistent with pyrolysis behavior.•FTIR spectrum at different temperature ...indicated two main pyrolysis stages.•Pyrolysis mechanism of waste bicycle tire was free radical mechanism.
Pyrolysis of waste tire is attracting widespread interest recently because of the great potential in waste valorization treatment. In this study, the thermal decomposition behavior, pyrolysis mechanism and products distribution of waste bicycle tire were investigated by means of TG-FTIR and Py-GC/MS. According to the TG results, two main pyrolysis stages of waste bicycle tire were observed, which were considered as the decomposition of rubber (285–531 °C) and further pyrolysis of pyrolytic products (663–847 °C), respectively. The volatiles release characteristics and FTIR spectrum at different temperatures exhibited good consistency with pyrolysis behavior. A detail information of pyrolysis products was analyzed by Py-GC/MS, which mainly include gaseous, alkenes and aromatics. The pyrolysis mechanism of waste bicycle tire was belong to free radical reaction, and the possible further pyrolysis pathway of D-limonene and styrene was also presented. Moreover, the products distribution under different pyrolysis final temperatures and heating rates conditions were summarized. Thus, this study could enhance our understanding on more specific details for the pyrolysis process of waste tire to some extent.
The effect of starch surface proteins on retrogradation of wheat starches were evaluated by rheometer, RVA, XRD, DSC, and TPA. An increase of the storage modulus and setback viscosity of starch ...pastes was observed after SDS and NaOH treatments. XRD resulted exhibited that recrystallinity of NaOH-treated and SDS-treated starch gels was increased to 10.33% and 11.15%, respectively, higher than that of native starch gel. Retrogradation enthalpy was increased from 3.5 J/g to 5.3 J/g for SDS-treated starch gels after 14 days storage at 4 °C. This was in line with the pronounced changes in gel firmness which was increased to 357g for SDS-treated starch. It suggested that removal of starch surface proteins apparently influenced the water mobility in starch gels and accelerated the retrogradation process.
Display omitted
•NaOH and SDS treatments were used to remove the starch surface proteins.•Removing proteins increased the storage modulus and setback viscosity of starch paste.•Recrystallinity of NaOH-treated and SDS-treated starch gels was higher than native one.•SDS treatment promoted retrogradation enthalpy from 3.5 J/g to 5.3 J/g.•Firmness increased from 261g for native starch to 357g for SDS-treated starch after storage.
The unique combinations of hard and soft components with core/shell structures were proposed to synthesize high strength nanocomposite hydrogels. The elastomeric hydrogels containing rod-like ...cellulose nanocrystals (CNCs) core and polyacrylamide shell were made from aqueous solutions via free radical polymerization in the absence of chemical cross-links. The obtained hydrogels possessed greater tensile strength and elongation ratio when compared with chemically cross-linked counterparts. Oscillatory shear experiments indicated that CNCs interacted with polymer matrix via both chemical and physical interactions and contributed to the rubbery elasticity of the hydrogels. The nanocomposite hydrogels were more viscous than the chemical hydrogels, suggesting the addition of CNC led to the increase of energy dissipating and viscoelastic properties. The network structure model was proposed and it suggested that the high extensibilities and fracture stresses were related to the well-defined network structures with low cross-linking density and lack of noncovalent interactions among polymer chains, which may promote the rearrangements of network structure at high deformations.
•A novel polysaccharide fraction is isolated from the bulbs of Lilium lancifolium Thunb.•The structural characterisation of LP2-1 was studied.•The physicochemical properties including rheology of ...LP2-1 were investigated.•In vitro antioxidant activities of LP2-1 were determined.
A novel polysaccharide fraction (LP2-1) was isolated and purified from the edible bulbs of Lilium lancifolium Thunb. by DEAE cellulose chromatography and Sephacryl S-400 size-exclusion chromatography. The structural characterisation, physicochemical properties and antioxidant activity of LP2-1 were investigated. The results showed that LP2-1 had an average molecular weight of approximately 8.52×103kDa and was mainly composed of l-rhamnopyranose, d-arabinofuranose, d-glucopyranose and d-galactopyranose in the molar ratio of 1.88:2.13:1.00:2.50, and major functional groups of LP2-1 were COO and OH. The viscoelastic properties of LP2-1 systems exhibited a gel-like behaviour, with storage modulus higher than loss modulus, and both moduli increased with increasing Ca2+ concentration. In addition, LP2-1 had DPPH and hydroxyl radicals scavenging activities, and also had the strong reducing power and chelating activity on ferrous ion. These results suggest that LP2-1 has good antioxidant activity and can be used in food industry.
•Starches isolated from frozen soft and hard wheat dough were investigated.•Freezing effect was more pronounced in hard group than in the soft group.•Freezing-treated hard wheat starch (HWS) had more ...damaged starch.•HWS showed lower amounts of proteins, lipids and amylose after freezing treatment.•Freezing-treated HWS had a lower bread specific volume and harder crumb firmness.
Properties of starches isolated from soft and hard wheat dough after freezing/thawing (F/T) treatment were investigated. Significance of results was observed between isolated hard wheat starch (HWS) and soft wheat starch (SWS), but both cultivars showed an increase in the amounts of damaged starch and leaching proteins, lipids, and amylose with F/T cycles. The freezing-treated HWS exhibited a higher swelling power and peak, trough, breakdown and final viscosity than SWS after F/T treatment. The onset, peak and conclusion gelatinization temperatures and the enthalpy of the isolated HWS determined by differential scanning calorimetry, decreased throughout F/T cycles. Concomitantly, the bread containing freezing-treated HWS exhibited a lower bread specific volume and harder crumb firmness, which might be associated with its significant structural changes induced by F/T treatment.
An uncontrolled inflammatory response is a critical pathophysiological feature of sepsis. Mesenchymal stem cells (MSCs) induce macrophage phenotype polarization and reduce inflammation in sepsis. ...MSC-secreted transforming growth factor beta (TGF-β) participated in the immune modulatory function of MSCs. However, the underlying mechanism of MSC-secreted TGF-β was not fully elucidated in regulation macrophage M2-like polarization.
The paracrine effects of MSCs on macrophage polarization were studied using a co-culture protocol with LPS-stimulated RAW264.7 cells/mouse peritoneal macrophages and MSCs. The effect of TGF-β in the co-culture system was blocked by the TGF-β receptor inhibitor. To determine the role of MSC-secreted TGF-β, we used recombinant TGF-β to culture with LPS-stimulated RAW264.7 cells. In addition, we employed antibody microarray analysis to determine the mechanisms of MSC secreted TGF-β on LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage M2-like polarization. Furthermore, we used an Akt inhibitor and a FoxO1 inhibitor to inhibit the Akt/FoxO1 pathway. The nuclear translocation of FoxO1 was detected by Western blot.
MSCs induced LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage polarization towards the M2-like phenotype and significantly reduced pro-inflammatory cytokine levels via paracrine, which was inhibited by TGF-β receptor inhibitor. Furthermore, we found that MSC-secreted TGF-β enhanced the macrophage phagocytic ability. The antibody microarray analysis and Western blot verified that TGF-β treatment activated the Akt/FoxO1 pathway in LPS-stimulated macrophages, TGF-β-induced FoxO1 nuclear translocation and obviously expressed in the cytoplasm, the effects of TGF-β regulatory effects on LPS-stimulated macrophage were inhibited by pre-treatment with Akt inhibitor and FoxO1 inhibitor.
TGF-β secreted by MSCs could skew LPS-stimulated macrophage polarization towards the M2-like phenotype, reduce inflammatory reactions, and improve the phagocytic ability via the Akt/FoxO1 pathway, providing potential therapeutic strategies for sepsis.
PDF
