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Sun Young Park,1 Beomjin Kim,2 Zhengwei Cui,3 Geuntae Park,4 Young-Whan Choi3 1Bio-IT Fusion Technology Research Institute, Pusan National University, Busan 609-735, Korea; 2Department of Nanomaterials Engineering, Pusan National University, Busan 609-735, Korea; 3Department of Horticultural Bioscience, Pusan National University, Myrang 627-706, Korea; 4Department of Nanofusion Technology, Graduate School, Pusan National University, Busan, 609-735, KoreaCorrespondence: Geuntae ParkDepartment of Nanofusion Technology, Graduate School, Pusan National University, Busan 609-735, Republic of KoreaTel +82-51-510-3740Fax +82-51-518-4113Email gtpark@pusan.ac.krYoung-Whan ChoiDepartment of Horticultural Bioscience, Pusan National University, Miryang 627-706, Republic of KoreaTel +82-55-350-5522Fax +82-55-350-5529Email ywchoi@pusan.ac.krPurpose: We aimed to study green-synthesized gold nanoparticles (GNPs) from Maclura tricuspidata (MT) root (MTR), stem (MTS), leaf (MTL), and fruit (MTF) extracts and evaluate their anti-metastatic properties in hepatocellular carcinoma cells. Maclura tricuspidata belongs to the Moraceae family and is widely used as a traditional medicinal plant given its biological activities.Methods: We quantified the phenolic and flavonoid contents, reducing capacity, and antioxidant activity of all four extracts. The facile and optimum synthesis of MT-GNPs was visualized using UV-vis spectra and dynamic light scattering (DLS). Surface morphology, selected area electron diffraction (SAED), and fast Fourier transform (FFT) pattern of MT-GNPs were assessed using high-resolution transmission electron microscopy (HR-TEM). The crystallized gold pattern of MT-GNPs was evaluated using energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The functionalizing ligands of MT-extracts and MT-GNPs were determined using Fourier-transform infrared spectroscopy (FT-IR). The photocatalytic capabilities of MT-GNPs were assessed by measuring the reduction of rhodamine B and methylene blue. Cell viability assay was detected using Cell Counting Kit-8 solution. Anti-migratory and anti-invasive effects were assessed using cell migration and invasion assays. Matrix metalloproteinase (MMP)-9 and phospholipase D (PLD) enzymatic activities were measured using gelatin zymography and Amplex Red PLD assay, respectively. Western blotting and luciferase assay were used to detect protein expression.Results: All extracts had high phenolic and flavonoid contents and strong antioxidant and reducing capacities. Results from UV-Vis spectra, DLS, HR-TEM, EDS, XRD, and FT-IR showed the successful formation of MT-GNP with surface morphology, crystallinity, reduction capacity, capsulation, and stabilization. MTR-GNPs and MTS-GNPs had better catalytic activities than MTL-GNPs and MTF-GNPs for reduction of methylene blue and rhodamine B. Moreover, MTS-GNPs and MTR-GNPs exhibited the highest anti-migratory and anti-invasive potential and seemed to be more biologically active than the MTS and MTR extracts. Treatment with MT-GNPs decreased the enzymatic activity, translation levels of MMP-9 and PLD1. Our results showed that MTS-GNPs and MTR-GNPs could dramatically reverse transforming growth factor-β-induced vimentin and N-cadherin upregulation and E-cadherin downregulation.Conclusion: The application of GNPs as a potential treatment approach for hepatocellular carcinoma can improve therapeutic efficiency.Keywords: MT-GNPs, Maclura tricuspidata, hepatocellular carcinoma cells, epithelial–mesenchymal transition

By discharging aerosols from a high-pressure vessel through a nozzle, an improved continuous aerosol dispersion system can disperse nanoparticle agglomerates to almost primary nanoparticle size. The system’s high-pressure dispersion was modelled and numerically simulated using the Taylor expansion method of moments. The strong turbulent shear near the nozzle could achieve the same level as the van der Waals force, which is the main mechanism for deagglomerating nanoparticle agglomerates. The change in nanoparticle size was determined to be proportional to the pressure drop between the nozzle inlet and outlet. Nanoparticle breakup was also observed to be affected by the fractional dimension and primary size of particles.

Microwave-assisted and ultrasound-assisted extraction assays were used to isolate total flavonoids (TF) from Osmanthus fragrans flowers. The effects of the solid-liquid ratio, ethanol concentration, microwave power, microwave extraction time, ultrasonic power and ultrasonic extraction time on the yield of TF were studied. A sequential combination of microwave- and ultrasound-assisted extraction (SC-MUAE) methods was developed, which was subsequently optimized by Box-Behnken design-response surface methodology (BBD-RSM). The interaction effects of the ethanol concentration (40-60%), microwave extraction time (5-7 min), ultrasonic extraction time (8-12 min) and ultrasonic power (210-430 W) on the yield of TF were investigated. The optimum operating parameters for the extraction of TF were determined to be as follows: ethanol concentration (48.15%), microwave extraction time (6.43 min), ultrasonic extraction time (10.09 min) and ultrasonic power (370.9 W). Under these conditions, the extraction yield of TF was 7.86 mg/g.

In this study, a microwave-sensitive solid acid catalyst was successfully synthesized from sweet potatoes via a simple process. The catalyst was proven to have superior microwave-sensitive and homogeneous properties. The physicochemical properties were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), Fourier-transform infrared spectra (FT-IR), thermogravimetric (TGA), scanning electron microscope (SEM) and elemental analysis (EA). Results showed that the total acid density and specific surface area for the catalyst were 6.35 mmol/g and 78.35 m2/g, respectively. The elemental sulfur content reached 7.449% after sulfonation and the catalytic activity could reach over 91% within 30 min with microwave power density of 1.0 W/mL. The catalytic reaction temperature should not exceed 200 °C, as shown in TGA curve, and the moisture content in the oil raw material should be within 1%–2%. The catalyst deactivated gradually to 64.38% after reutilization five times, but the catalytic activity could be simply regenerated by re-sulfonation, albeit slightly reduced (87.56%). The shift of diffraction peaks in the XRD patterns and new absorption peaks at 619.98 and 1190.49 cm−1 of FT-IR spectra demonstrated that the –SO3H group was effectively attached to the catalyst. The SEM images displayed a loose and porous amorphous structure in the end catalyst.

The solvent-soluble silicon (Si) and boron-silicon (B-Si) doped coal-tar pitches were synthesized with the co-pyrolysis of a mixture of the toluene-soluble fraction of the coal-tar pitch (TSP), polycarbosilane and pyridine borane. The C-Si and C-B-Si alloys were obtained with a carbonization treatment of the synthetic Si and B-Si doped coal-tar pitches at 1000-1600 °C for 1 h. The physical properties of the Si and B-Si doped coal-tar pitches, such as the softening point, quinoline insolubles, the volatile content and the pyrolysis yield were determined. The influences of the pyridine-borane content in raw materials and the carbonization temperature on the composition, microstructure and oxidation resistance of the C-Si and C-B-Si alloys were investigated. The results show that the C-B-Si alloys are composed of SiC, B2O3 and carbon, while the silicon, boron and oxygen elements are uniformly dispersed in the carbon matrix. In most cases, the oxidation resistance of the C-B-Si alloy is better than that of the C-Si alloy, owing to the sintering-aiding action of B2O3 and the anti-oxidation synergism of the SiO2 and B2O3 formed during oxidation. The higher the carbonization temperature, the larger is the grain size of the SiC in the C-B-Si alloy. A large grain size leads to an increase in the initial oxidation temperature of the SiC, which is unfavorable for the formation of a protective glassy film on the surface of the C-B-Si alloys. As a result, the C-B-Si alloy obtained with the carbonization at 1200 °C shows a better oxidation resistance than that obtained with the carbonization at 1600 °C under the same oxidation conditions. Topila premogove katranske smole, dopirane s topnim silicijem (Si) in bor-silicijem (B-Si), so bila sintetizirana s kopirolizo mešanice v toluenu topne frakcije premogove katranske smole (TSP), polikarbonsilana in piridin borana. Zlitine C-Si in C-B-Si so bile dobljene s karbonizacijsko obdelavo premogove katranske smole, dopirane s sintetičnim Si in B-Si 1 h pri 1000-1600°C. Določene so bile fizikalne lastnosti premogove katranske smole, dopirane s Si in B-Si, točka mehčanja, trdni delci ogljika, vsebnost hlapnih snovi in izkoristek pirolize. Preiskovan je bil vpliv vsebnosti piridin boranav surovini in karbonizacijska temperatura na sestavo, mikrostrukturo in oksidacijsko odpornost zlitin C-Si in C-B-Si. Rezultati kažejo, da so zlitine C-B-Si sestavljene iz SiC, B2O3 in ogljika, pri čemer so elementi ogljik, silicij, bor in kisik enakomerno razpršeni po osnovi iz ogljika. Odpornost proti oksidaciji je v večini primerov pri zlitini C-B-Si boljša od zlitine C-Si zaradi dodatnega učinka B2O3 in protioksidacijske sinergije SiO2 in B2O3, ki nastajata med oksidacijo. Čim višja je temperatura karbonizacije, tem večja postajajo zrna zlitine SiC in C-B-Si. Večja kristalna zrna povzročijo povišanje temperature začetka oksidacije SiC, kar je neugodno za nastanek steklaste zaščitne plasti na površini zlitin C-B-Si. Rezultat tega je, da zlitina C-B-Si, dobljena pri karbonizaciji pri 1200 °C, pri enakih razmerah za oksidacijo kaže boljšo odpornost proti oksidaciji kot zlitina, pridobljena s karbonizacijo pri 1600 °C.

Nowadays, polyimide-derived graphite films with high thermal conductivity have been increasingly applied in many cutting-edge fields needing thermal management, such as highly integrated microelectronics and wireless communication technologies. This chapter first introduces a variety of functional graphite films with high thermal conductivity of 500–2000 W/m K in the planar direction, then provides the preparation technology (including lab-scale preparation and industrial production) and quality control strategy of high-thermal-conductivity graphite films, which are derived from a special polymer- polyimide (PI) by carbonization and graphitization treatments through a suitable molding press in a vacuum furnace. The morphology, microstructure and physical properties as well as the microstructural evolution and transformation mechanism of PI films during the whole process of high-temperature treatment are comprehensively introduced. The nature of PI precursor (e.g., the molecular structure and planar molecular orientation) and preparation technics (e.g., heat-treatment temperature and molding pressure) are critical factors influencing their final physical properties. Currently challenged by the emerging of graphene-based graphite films, the latest developments and future prospects of various PI-derived carbons and composites (beyond films) with high thermal conductivity have been summarized at the end. This chapter may shed light on a promising and versatile utilization of PI-derived functional carbon materials for advanced thermal management.

Carbonaceous mesophase with a nematic liquid crystal structure possesses an easily graphitizable characteristic and can be used as a promising raw material to prepare anisotropic carbon and graphite materials with high performance and multifunction. Therefore, the carbonaceous mesophase occupies a pivotal and irreplaceable position in many frontier and cutting-edge fields. The controllable preparation and characterization of carbonaceous mesophase derived from a model molecule (i.e., naphthalene) are presented, especially the formation, development, and transformation of anisotropic liquid crystalline mesophase in the synthetic naphthalene pitch during the process of liquid-phase carbonization (350–450°C). The increasing applications of naphthalene-based carbonaceous mesophase as an ideal precursor material for fabricating representative advanced carbon materials with high added value (e.g., mesophase pitch-derived coke, mesocarbon microbeads, mesophase pitch-based carbon foam, high-modulus mesophase pitch-based carbon fibers, and high-thermal-conductivity carbon-based composites, etc.) are reviewed in detail in this chapter.