Статті в журналах: "Porous carbon matrice"

1

Kim, Hyun-Chul, and Seong Huh. "Porous Carbon-Based Supercapacitors Directly Derived from Metal–Organic Frameworks." Materials 13, no. 18 (September 22, 2020): 4215. http://dx.doi.org/10.3390/ma13184215.

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Numerously different porous carbons have been prepared and used in a wide range of practical applications. Porous carbons are also ideal electrode materials for efficient energy storage devices due to their large surface areas, capacious pore spaces, and superior chemical stability compared to other porous materials. Not only the electrical double-layer capacitance (EDLC)-based charge storage but also the pseudocapacitance driven by various dopants in the carbon matrix plays a significant role in enhancing the electrochemical supercapacitive performance of porous carbons. Since the electrochemical capacitive activities are primarily based on EDLC and further enhanced by pseudocapacitance, high-surface carbons are desirable for these applications. The porosity of carbons plays a crucial role in enhancing the performance as well. We have recently witnessed that metal–organic frameworks (MOFs) could be very effective self-sacrificing templates, or precursors, for new high-surface carbons for supercapacitors, or ultracapacitors. Many MOFs can be self-sacrificing precursors for carbonaceous porous materials in a simple yet effective direct carbonization to produce porous carbons. The constituent metal ions can be either completely removed during the carbonization or transformed into valuable redox-active centers for additional faradaic reactions to enhance the electrochemical performance of carbon electrodes. Some heteroatoms of the bridging ligands and solvate molecules can be easily incorporated into carbon matrices to generate heteroatom-doped carbons with pseudocapacitive behavior and good surface wettability. We categorized these MOF-derived porous carbons into three main types: (i) pure and heteroatom-doped carbons, (ii) metallic nanoparticle-containing carbons, and (iii) carbon-based composites with other carbon-based materials or redox-active metal species. Based on these cases summarized in this review, new MOF-derived porous carbons with much enhanced capacitive performance and stability will be envisioned.

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2

Nazhipkyzy, Meruyert, Tolganay Temirgaliyeva, Aizhan A. Zhaparova, Araylim Nurgain, Bakhytzhan T. Lesbayev, Zulkhair A. Mansurov, and Nikolay G. Prikhodko. "Synthesis of Porous Carbon Material and its Use for Growing Carbon Nanotubes." Materials Science Forum 886 (March 2017): 32–36. http://dx.doi.org/10.4028/www.scientific.net/msf.886.32.

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The scales of porous carbon materials usage are constrained by their considerably high cost. Therefore, development of new methods for production of porous carbon with the necessary complex of properties from cheap raw materials is actual. Also, porous carbon materials can be used for growth of carbon nanotubes as a matrices of catalyst particles. Herein, the method of fabrication porous carbon materials from waste of oil industry and their use as a matrices of catalyst particles to growth of CNT was developed. CNTs was synthesized by CVD using as hydrocarbon source - propan-butane gas mixture, as catalyst - Ni particles at 650°C, 700°C, 750°C, 800°C. Obtained carbon materials was investigated by Raman spectroscopy and by scanning electron microscope. Investigations on the properties of the obtained porous materials show soot particles sedimented in pores reduce well nanoparticles of metals from salts which act as nuclei for the growth of multiwall carbon nanotubes during pyrolysis of hydrocarbons by CVD method.

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3

Li, Mian, Xiaotian Liu, Yueping Xiong, Xiangjie Bo, Yufan Zhang, Ce Han, and Liping Guo. "Facile synthesis of various highly dispersive CoP nanocrystal embedded carbon matrices as efficient electrocatalysts for the hydrogen evolution reaction." Journal of Materials Chemistry A 3, no. 8 (2015): 4255–65. http://dx.doi.org/10.1039/c4ta06630h.

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4

Yang, Wen, Li Li, Yongzhao Hou, Yun Liu, and Xinwei Xiao. "Enhanced Electromagnetic Wave Absorption of SiOC/Porous Carbon Composites." Materials 15, no. 24 (December 12, 2022): 8864. http://dx.doi.org/10.3390/ma15248864.

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Carbon-based materials have been widely explored as electromagnetic (EM) wave absorbing materials with specific surface areas and low density. Herein, novel porous carbon/SiOC ceramic composites materials (porous C/sp-SiOC) were prepared from the binary mixture, which used the low cost pitch as carbon resource and the polysilylacetylene (PSA) as SiOC ceramic precursor. With the melt-blending-phase separation route, the PSA resin formed micro-spheres in the pitch. Then, numerous SiOC ceramic micro-spheres were generated in porous carbon matrices during the pyrolysis process. By changing the percent of SiOC, the microstructure and wave absorption of porous C/sp-SiOC composites could be adjusted. The synergistic effect of the unique structure, the strong interfacial polarization, and the optimized impedance matching properties contributed to the excellent absorption performance of porous C/sp-SiOC composites. The minimum reflection loss for porous C/sp-SiOC absorber reached −56.85 dB, and the widest effective bandwidth was more than 4 GHz with a thickness of only 1.39 mm. This presented research provides an innovative and practical approach to developing high-performance porous carbon-based microwave absorption materials from green chemistry.

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5

Zaarour, Moussa, Jurjen Cazemier, and Javier Ruiz-Martínez. "Recent developments in the control of selectivity in hydrogenation reactions by confined metal functionalities." Catalysis Science & Technology 10, no. 24 (2020): 8140–72. http://dx.doi.org/10.1039/d0cy01709d.

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Confining metal active species in the voids of porous solid matrices such as zeolites, metal–organic frameworks (MOFs), and carbon nanotubes (CNTs) can bring fascinating key advantages in the field of selective hydrogenation reactions.

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6

Pinsky, Dina, Noam Ralbag, Ramesh Kumar Singh, Meirav Mann-Lahav, Gennady E. Shter, Dario R. Dekel, Gideon S. Grader, and David Avnir. "Metal nanoparticles entrapped in metal matrices." Nanoscale Advances 3, no. 15 (2021): 4597–612. http://dx.doi.org/10.1039/d1na00315a.

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Metallic nanoparticles have been traditionally dispersed on ceramics and carbons, but never on porous metals. Methods for the preparation of such materials are described, and catalysis is demonstrated for reductions and for H₂ electro-oxidation.

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7

Fraczek-Szczypta, Aneta, Ewa Stodolak-Zych, Szymon Jurdziak, and Marta Blazewicz. "Polymer Nanocomposite Scaffolds Modified with Carbon Nanotubes for Tissue Regeneration." Materials Science Forum 714 (March 2012): 245–53. http://dx.doi.org/10.4028/www.scientific.net/msf.714.245.

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Among the many applications of polylactide (PLA) in medicine, one of the most famous is porous scaffold for bone and cartilage regeneration. A new direction in the development of biodegradable polymer scaffolds is their modification using different types of nanoadditives. One type of these nanomaterials could be carbon nanotubes (CNT), which could influence the mechanical, electrical, physicochemical and biological properties of polymer matrices. Porous nanocomposite scaffolds were prepared using different techniques, such as salt leaching and a combination of salt leaching and gas foaming techniques. The bioactivity of MWCNTs was determined through their incubation in simulated body fluid (SBF) and verified using scanning electron microscopy (SEM). The best concentration of nanoadditives in the polymer matrices was evaluated on the basis of mechanical and in vitro tests of nanocomposite films using a universal testing machine (Zwick) and osteoblast-like human cells (MG63). The morphology, porosity and mechanical properties of the porous scaffold before and after modification with MWCNTs were evaluated using SEM, hydrostatic weighing and a universal test machine.

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8

Fu, Yun, Zhian Zhang, Xing Yang, Yongqin Gan, and Wei Chen. "ZnS nanoparticles embedded in porous carbon matrices as anode materials for lithium ion batteries." RSC Advances 5, no. 106 (2015): 86941–44. http://dx.doi.org/10.1039/c5ra15108b.

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In situ synthesis of a novel zinc sulfide/porous carbon composite is achieved by virtue of the metal–organic frameworks strategy. The composite exhibits significant electrochemical performance as an anode material for lithium ion batteries.

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9

Sleptsov, V. V., L. V. Kozitov, A. O. Diteleva, D. Yu Kukushkin, and A. A. Nagaev. "A new generation of nanocomposite materials based on carbon and titanium for use in supercapacitor energy storage devices." Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering 22, no. 3 (January 19, 2020): 212–18. http://dx.doi.org/10.17073/1609-3577-2019-3-212-218.

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In this paper, promising nanocomposite materials based on carbon and titanium are considered. It is shown that the use of a highly porous matrix is of particular interest. Materials based on such matrices have minimal weight and high strength characteristics. The paper also describes composites based on porous carbon fibers with metal oxides. The directions for producing composites can be divided into three types: matrix method, coating of finished nanoparticles with an inert shell, and the formation of nanoparticles and matrices in one process. The coating of nanoparticles with an inert shell prevents their oxidation and preserves the necessary magnetic properties. When using methods such as IR pyrolysis, arc evaporation forms third-party metal-carbon phases that pollute the resulting material. To avoid this, reducing agents are used, for example, hydrogen when coking nanoparticles in a methane plasma current restores metal particles from its Sol-gel and prevents them from reacting with carbon. But with this method, it is difficult to control the particle size. Using a ready-made matrix allows you to control the size of nanoparticles. However, this method uses high temperatures, and sometimes hydrogen, which complicates the production process. The main problem in the field of nanocomposites is the search for more technological, simple, cheap and environmentally friendly methods for obtaining nanocomposites with high performance characteristics. The developed technology for forming the pore space of the initial carbon matrix does not have the above disadvantages. This technology has a simple, cheap, environmentally friendly design. high temperatures are not used in the process of producing nanocomposites and third-party metal-carbon phases are not formed. The resulting nanocomposite materials were used as electrodes for ultra-high-volume capacitor structures. When studying the capacitance and electrical characteristics of samples, it was found that the formation of metal on a porous carbon matrix can significantly reduce the internal resistance of the cell and increase the specific energy consumption.

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10

Kubota, Yuki, Toshiki Fujita, Yusei Kaneda, Ryo Inoue, and Yasuo Kogo. "Thermal Protection Performance of Porous Carbon Ablators with Three Different Matrices." Journal of Spacecraft and Rockets 55, no. 5 (September 2018): 1222–29. http://dx.doi.org/10.2514/1.a34234.

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11

Bogorodskii, S. E., L. I. Krotova, A. V. Mironov, and V. K. Popov. "Fabrication of highly porous bioresorbable polymer matrices using supercritical carbon dioxide." Russian Journal of Physical Chemistry B 7, no. 8 (December 2013): 916–23. http://dx.doi.org/10.1134/s1990793113080034.

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12

Zakharov, Yu A., G. Yu Simenyuk, V. M. Pugachev, V. G. Dodonov, N. V. Pavelko, T. S. Manina, and Ch N. Barnakov. "Nanostructured composites based on highly porous carbon matrices filled with gold." Nanotechnologies in Russia 10, no. 5-6 (May 2015): 388–99. http://dx.doi.org/10.1134/s1995078015030192.

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13

Sun, Miaotian, Zeynep Ülker, Zhixing Chen, Sivaraman Deeptanshu, Monika Johannsen, Can Erkey, and Pavel Gurikov. "Development and Validation of Retention Models in Supercritical Fluid Chromatography for Impregnation Process Design." Applied Sciences 11, no. 15 (July 31, 2021): 7106. http://dx.doi.org/10.3390/app11157106.

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The retention factor is the key quantity for the thermodynamic analysis of the retention mechanism in chromatographic experiments. In this work, we measure retention factors for moderately polar solutes on four silica-based porous matrices as stationary phases by supercritical fluid chromatography. Elution of the solutes is only possible with binary mixtures of supercritical carbon dioxide (sc-CO2) and modifier (methanol) due to the low polarity of pure sc-CO2. The addition of modifiers makes the retention mechanism more complex and masks interactions between solute and stationary phase. In this work, we develop and validate several retention models that allow the obtaining of retention factors in modifier-free sc-CO2. Such models pave the way for quantifying adsorption interactions between polar solutes and non-swellable porous matrices in pure sc-CO2 based on retention data obtained in sc-CO2/modifier mixtures. The obtained information will thereby facilitate the understanding and design of impregnation processes, which are often performed in modifier-free conditions.

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14

He, Ting, Bingzhang Lu, Yang Chen, Yong Wang, Yaqiang Zhang, John L. Davenport, Alan P. Chen, et al. "Nanowrinkled Carbon Aerogels Embedded with FeNx Sites as Effective Oxygen Electrodes for Rechargeable Zinc-Air Battery." Research 2019 (December 20, 2019): 1–13. http://dx.doi.org/10.34133/2019/6813585.

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Rational design of single-metal atom sites in carbon substrates by a flexible strategy is highly desired for the preparation of high-performance catalysts for metal-air batteries. In this study, biomass hydrogel reactors are utilized as structural templates to prepare carbon aerogels embedded with single iron atoms by controlled pyrolysis. The tortuous and interlaced hydrogel chains lead to the formation of abundant nanowrinkles in the porous carbon aerogels, and single iron atoms are dispersed and stabilized within the defective carbon skeletons. X-ray absorption spectroscopy measurements indicate that the iron centers are mostly involved in the coordination structure of FeN4, with a minor fraction (ca. 1/5) in the form of FeN3C. First-principles calculations show that the FeNx sites in the Stone-Wales configurations induced by the nanowrinkles of the hierarchically porous carbon aerogels show a much lower free energy than the normal counterparts. The resulting iron and nitrogen-codoped carbon aerogels exhibit excellent and reversible oxygen electrocatalytic activity, and can be used as bifunctional cathode catalysts in rechargeable Zn-air batteries, with a performance even better than that based on commercial Pt/C and RuO2 catalysts. Results from this study highlight the significance of structural distortions of the metal sites in carbon matrices in the design and engineering of highly active single-atom catalysts.

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15

Chuah, Chong Yang, Junghyun Lee, Juha Song, and Tae-Hyun Bae. "Carbon Molecular Sieve Membranes Comprising Graphene Oxides and Porous Carbon for CO2/N2 Separation." Membranes 11, no. 4 (April 12, 2021): 284. http://dx.doi.org/10.3390/membranes11040284.

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To improve the CO2/N2 separation performance, mixed-matrix carbon molecular sieve membranes (mixed-matrix CMSMs) were fabricated and tested. Two carbon-based fillers, graphene oxide (GO) and activated carbon (YP-50F), were separately incorporated into two polymer precursors (Matrimid® 5218 and ODPA-TMPDA), and the resulting CMSMs demonstrated improved CO2 permeability. The improvement afforded by YP-50F was more substantial due to its higher accessible surface area. Based on the gas permeation data and the Robeson plot for CO2/N2 separation, the performances of the CMSMs containing 15 wt % YP-50F and 15 wt % GO in the mixed polymer matrix surpassed the 2008 Robeson upper bound of polymeric membranes. Hence, this study demonstrates the feasibility of such membranes in improving the CO2/N2 separation performance through the appropriate choice of carbon-based filler materials in polymer matrices.

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16

Isaeva, Vera I., Marina D. Vedenyapina, Alexandra Yu Kurmysheva, Dirk Weichgrebe, Rahul Ramesh Nair, Ngoc Phuong Thanh Nguyen, and Leonid M. Kustov. "Modern Carbon–Based Materials for Adsorptive Removal of Organic and Inorganic Pollutants from Water and Wastewater." Molecules 26, no. 21 (November 1, 2021): 6628. http://dx.doi.org/10.3390/molecules26216628.

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Currently, a serious threat for living organisms and human life in particular, is water contamination with persistent organic and inorganic pollutants. To date, several techniques have been adopted to remove/treat organics and toxic contaminants. Adsorption is one of the most effective and economical methods for this purpose. Generally, porous materials are considered as appropriate adsorbents for water purification. Conventional adsorbents such as activated carbons have a limited possibility of surface modification (texture and functionality), and their adsorption capacity is difficult to control. Therefore, despite the significant progress achieved in the development of the systems for water remediation, there is still a need for novel adsorptive materials with tunable functional characteristics. This review addresses the new trends in the development of new adsorbent materials. Herein, modern carbon-based materials, such as graphene, oxidized carbon, carbon nanotubes, biomass-derived carbonaceous matrices—biochars as well as their composites with metal-organic frameworks (MOFs) and MOF-derived highly-ordered carbons are considered as advanced adsorbents for removal of hazardous organics from drinking water, process water, and leachate. The review is focused on the preparation and modification of these next-generation carbon-based adsorbents and analysis of their adsorption performance including possible adsorption mechanisms. Simultaneously, some weak points of modern carbon-based adsorbents are analyzed as well as the routes to conquer them. For instance, for removal of large quantities of pollutants, the combination of adsorption and other methods, like sedimentation may be recommended. A number of efficient strategies for further enhancing the adsorption performance of the carbon-based adsorbents, in particular, integrating approaches and further rational functionalization, including composing these adsorbents (of two or even three types) can be recommended. The cost reduction and efficient regeneration must also be in the focus of future research endeavors. The targeted optimization of the discussed carbon-based adsorbents associated with detailed studies of the adsorption process, especially, for multicomponent adsorbate solution, will pave a bright avenue for efficient water remediation.

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17

Zakharov, Yu A., Z. R. Ismagilov, V. M. Pugachev, A. N. Voropai, R. P. Kolmykov, V. G. Dodonov, T. S. Manina, Ch N. Barnakov, and A. V. Samarov. "Nanostructured composites based on porous carbon matrices filled with nickel hydroxide crystallites." Inorganic Materials 51, no. 4 (March 18, 2015): 405–11. http://dx.doi.org/10.1134/s0020168515040196.

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18

Seta, Ewelina, Weronika A. Lotowska, Iwona A. Rutkowska, Anna Wadas, Adrianna Raczkowska, Marta Nieckarz, Katarzyna Brzostek, and Pawel J. Kulesza. "Polyaniline-Supported Bacterial Biofilms as Active Matrices for Platinum Nanoparticles: Enhancement of Electroreduction of Carbon Dioxide." Australian Journal of Chemistry 69, no. 4 (2016): 411. http://dx.doi.org/10.1071/ch15744.

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A hybrid matrix composed of a porous polyaniline underlayer, a robust bacterial biofilm and a multiwalled carbon nanotube overlayer has been demonstrated to function as highly active support for dispersed Pt catalytic nanoparticles during the electroreduction of carbon dioxide in neutral medium (phosphate buffer at pH 6.1). In contrast with bare Pt nanoparticles (deposited at a glassy carbon substrate), application of the hybrid system produces sizeable CO2-reduction currents in comparison to those originating from hydrogen evolution. The result is consistent with an enhancement in the reduction of carbon dioxide. However, the biofilm-based matrix tends to inhibit the catalytic properties of platinum towards proton discharge (competitive reaction) or even oxygen reduction. The hydrated structure permits easy unimpeded flow of aqueous electrolyte at the electrocatalytic interface. Although application of the polyaniline underlayer can be interpreted in terms of stabilization and improvement of the biofilm adherence, the use of carbon nanotubes facilitates electron transfer to Pt catalytic sites. It is apparent from the voltammetric stripping-type analytical experiments that, although formation of some methanol and methanoic acid cannot be excluded, carbon monoxide seems to be the main CO2-reduction product.

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19

Zakharov, Yu A., A. N. Voropay, N. M. Fedorova, V. M. Pugachev, A. V. Puzynin, Ch N. Barnakov, Z. R. Ismagilov, and T. S. Manina. "Highly Porous Carbon Materials Filled with Nickel Hydroxide Nanoparticles; Synthesis, Study, Application in Electrochemistry." Eurasian Chemico-Technological Journal 17, no. 3 (July 13, 2015): 187. http://dx.doi.org/10.18321/ectj243.

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Nickel hydroxide was deposited on the surface of the porous carbon to obtain a cathode material for supercapacitors. This work is the first part of the study of Ni(OH)2/С composite, which considers the conditions of its synthesis using two types of porous carbon matrices with a highly developed specific surface area (1000–3000 m2/g) and two types of precursors (NiCl2*6H2O and Ni(N3)2). The morphology of the systems, in particular the shape and size characteristics of the hydroxide filler particles, was examined using the scanning electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption at 77 K. The measurements of capacity of the Ni(OH)2/С-electrodes were made in 6 M KOH using an asymmetric two-electrode cell (a porous carbon material with known electrode characteristics was employed as the counter electrode). The capacity was shown to decrease by 22–56% with increasing the scanning rate from 10 to 80 mV/s. A maximum capacity of the composite was obtained at a scanning rate of 10 mV/s was 346 F/g.

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20

Chagnes, A., F. Laplante, F. Kerdouss, P. Proulx, and H. Ménard. "Experimental and computational investigation of the electrocatalytic hydrogenation of phenol in an electrochemical cell." Canadian Journal of Chemistry 82, no. 5 (May 1, 2004): 641–48. http://dx.doi.org/10.1139/v04-019.

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The electrocatalytic hydrogenation (ECH) of phenol was carried out in aqueous media with a commercial Pd/Al2O3 (5% w/w) catalyst. A porous matrix of reticulated vitreous carbon (RVC) was used to study the porosity stirring speed coupling (PSSC) effect on the phenol hydrogenation to form cyclohexanone and cyclohexanol. In accordance with the PSSC, the electrode can act as a fluidized bed electrode or as an agglomerated electrode. Fluidized bed electrodes develop for low porosity matrices (1030 ppi, ppi = pores per inch) at high stirring speeds (>600 rpm), while agglomerated electrodes are obtained for high porosity matrices (60100 ppi) with moderate stirring speeds under cathodic polarization. The distribution of the volume fraction of the particles and the agglomeration of the particles have been simulated by computational fluid dynamic (CFD) methods with FLUENT software. For the agglomerated electrode, the numerical simulations demonstrate the beneficial contribution of the cathodic polarization to the agglomeration process. However, at 650 rpm, for the fluidized bed electrode, the volume fraction of the particles in the RVC does not account for the distinction in the ECH efficiency between the 30 ppi matrix and the 100 ppi matrix. For a given amount of Pd/Al2O3 catalyst, it is observed that the ECH rates depend on the PSSC and increase in the following order: 100/650 < 30/650 < 100/200. Key words: electrocatalytic hydrogenation (ECH), CFD, fluid mechanics, porous media, powder, porosity stirring speed coupling (PSSC), reticulated vitreous carbon (RVC).

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KUDELKO, KATERYNA, LIUDMYLA ROZHDESTVENSKAYA, YULIYA BORYSENKO, ANASTASIA MIKHNIUK та VIACHESLAV BARSUKOV. "ФОРМУВАННЯ ТА ХАРАКТЕРИЗАЦІЯ ПОРИСТОГО АНОДОВАНОГО ОКСИДУ АЛЮМІНІЮ, СИНТЕЗОВАНОГО ЕЛЕКТРОХІМІЧНО У ПРИСУТНОСТІ ОКИСЛЕНОГО ГРАФЕНУ". Technologies and Engineering, № 2 (24 грудня 2021): 48–59. http://dx.doi.org/10.30857/2786-5371.2021.2.5.

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Purpose of the research: studying the effect of addition of carbon nanosized modifier graphene oxide on the formation of a porous film during the electrochemical oxidation of aluminum.Methods: UV-VIS spectra of graphene oxide suspension were obtained using a spectrophotometer, the thermogravimetric characteristics of anodized alumina were determined using a thermal analyzer, the surface characteristics were determined by the low-temperature nitrogen sorption-desorption method, the surface was calculated by the BET method, the morphology and ultrastructure of the surface were determined using electron microscope.Results: the possibility of using carbon materials for the electrochemical oxidation of aluminum was shown. The obtained electron micrographs indicate the effect of the inserted carbon modifier (graphene oxide) on the morphology of resulting oxide. As a result of this process we observe the formation of the cellular surface of the aluminium oxide with smaller pores compared with sample after synthesis without the modifier.It was shown that the addition of graphene oxide (0.25%) in the oxalic acid (0,3М) electrolyte effects on the stability of the anodizing process, the specific surface area of the sample of anodized aluminum synthesized with graphene oxide is determined as 35.5 m3/g, and it is three times higher than sample without modifier. According to sorption studies, it could be noted that the presence of nanosized graphene oxide in oxalic acid electrolyte leads to the formation of honey-comb pores with a smaller radius (22 nm), while the total volume of micropores increases. The obtained results allow us to conclude that graphene oxide as modifier is promising material for the preparation of anodized aluminum oxide matrices. In the future, these matrices could be used in processes of solutions and gases separation.Conclusions: The addition of graphene oxide into the electrolyte changes structure of porous anodized aluminum oxide and has shown the possibility of controlling the porosity of films.

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Xia, Bingquan, Teng Liu, Wei Luo, and Gongzhen Cheng. "NiPt–MnOx supported on N-doped porous carbon derived from metal–organic frameworks for highly efficient hydrogen generation from hydrazine." Journal of Materials Chemistry A 4, no. 15 (2016): 5616–22. http://dx.doi.org/10.1039/c6ta00766j.

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Nitrogen-doped porous carbons derived from ZIF-7 annealing at different temperatures have been synthesized and used as support matrices to anchor NiPt alloy and MnO_x NPs. The resulting (Ni₃Pt₇)_0.5–(MnO_x)_0.5/NPC-900 exhibits superior catalytic activity with TOF values of 706 and 120 h⁻¹ at 323 K and 298 K respectively, higher than most reported values.

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23

Vasco, D. W. "On the propagation of a disturbance in a smoothly varying heterogeneous porous medium saturated with three fluid phases." GEOPHYSICS 78, no. 2 (March 1, 2013): L1—L26. http://dx.doi.org/10.1190/geo2012-0160.1.

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From the equations governing the deformation of a porous medium containing three fluid phases, I derive expressions for the phase velocity of the various modes of displacement. These expressions are valid for a medium with smoothly varying heterogeneity. There is a single mode of transverse displacement, similar in nature to an elastic shear wave. The four-phase velocities of the longitudinal modes of displacement are derived from the solutions of a quartic equation. The coefficients of the polynomial equation are written as linear sums of the determinants of 4 × 4 matrices. The matrices contain various combinations of the parameters from the governing equations. The three-phase expressions are compared to two-phase estimates for the case in which one of the fluid saturations vanishes. Also, in a numerical illustration, velocity variations of around 10% are associated with the cyclic injection of carbon dioxide and water into an oil-saturated reservoir.

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24

Zubair, Usman, Julia Amici, Sandra Martinez Crespiera, Carlotta Francia, and Silvia Bodoardo. "Rational design of porous carbon matrices to enable efficient lithiated silicon sulfur full cell." Carbon 145 (April 2019): 100–111. http://dx.doi.org/10.1016/j.carbon.2019.01.005.

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25

Scales, Nicholas, Jun Chen, Robert D. Aughterson, Inna Karatchevtseva, Attila Stopic, Gregory R. Lumpkin, and Vittorio Luca. "Porous ZrC-carbon microspheres as potential insoluble target matrices for production of 188W/188Re." Journal of Radioanalytical and Nuclear Chemistry 318, no. 2 (August 14, 2018): 835–47. http://dx.doi.org/10.1007/s10967-018-6059-y.

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26

Park, Jinseok, Jungmin Kim, Dae Soo Jung, Isheunesu Phiri, Hyeon-Su Bae, Jinseok Hong, Sojin Kim, Young-Gi Lee, Myung-Hyun Ryou, and Kyubock Lee. "Microalgae-Templated Spray Drying for Hierarchical and Porous Fe3O4/C Composite Microspheres as Li-ion Battery Anode Materials." Nanomaterials 10, no. 10 (October 20, 2020): 2074. http://dx.doi.org/10.3390/nano10102074.

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A method of microalgae-templated spray drying to develop hierarchical porous Fe3O4/C composite microspheres as anode materials for Li-ion batteries was developed. During the spray-drying process, individual microalgae serve as building blocks of raspberry-like hollow microspheres via self-assembly. In the present study, microalgae-derived carbon matrices, naturally doped heteroatoms, and hierarchical porous structural features synergistically contributed to the high electrochemical performance of the Fe3O4/C composite microspheres, enabling a discharge capacity of 1375 mA·h·g−1 after 700 cycles at a current density of 1 A/g. Notably, the microalgal frameworks of the Fe3O4/C composite microspheres were maintained over the course of charge/discharge cycling, thus demonstrating the structural stability of the composite microspheres against pulverization. In contrast, the sample fabricated without microalgal templating showed significant capacity drops (up to ~40% of initial capacity) during the early cycles. Clearly, templating of microalgae endows anode materials with superior cycling stability.

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Aguado, María, Laura Saldaña, Eduardo Pérez del Río, Judith Guasch, Marc Parera, Alba Córdoba, Joaquín Seras-Franzoso, et al. "Polylactide, Processed by a Foaming Method Using Compressed Freon R134a, for Tissue Engineering." Polymers 13, no. 20 (October 9, 2021): 3453. http://dx.doi.org/10.3390/polym13203453.

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Fabricating polymeric scaffolds using cost-effective manufacturing processes is still challenging. Gas foaming techniques using supercritical carbon dioxide (scCO2) have attracted attention for producing synthetic polymer matrices; however, the high-pressure requirements are often a technological barrier for its widespread use. Compressed 1,1,1,2-tetrafluoroethane, known as Freon R134a, offers advantages over CO2 in manufacturing processes in terms of lower pressure and temperature conditions and the use of low-cost equipment. Here, we report for the first time the use of Freon R134a for generating porous polymer matrices, specifically polylactide (PLA). PLA scaffolds processed with Freon R134a exhibited larger pore sizes, and total porosity, and appropriate mechanical properties compared with those achieved by scCO2 processing. PLGA scaffolds processed with Freon R134a were highly porous and showed a relatively fragile structure. Human mesenchymal stem cells (MSCs) attached to PLA scaffolds processed with Freon R134a, and their metabolic activity increased during culturing. In addition, MSCs displayed spread morphology on the PLA scaffolds processed with Freon R134a, with a well-organized actin cytoskeleton and a dense matrix of fibronectin fibrils. Functionalization of Freon R134a-processed PLA scaffolds with protein nanoparticles, used as bioactive factors, enhanced the scaffolds’ cytocompatibility. These findings indicate that gas foaming using compressed Freon R134a could represent a cost-effective and environmentally friendly fabrication technology to produce polymeric scaffolds for tissue engineering approaches.

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Christov, Ivan C., and Hari S. Viswanathan. "Introduction: energy and the subsurface." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2078 (October 13, 2016): 20150430. http://dx.doi.org/10.1098/rsta.2015.0430.

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This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO 2 ) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection. This article is part of the themed issue ‘Energy and the subsurface’.

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Munonde, Tshimangadzo S., and Philiswa N. Nomngongo. "Nanocomposites for Electrochemical Sensors and Their Applications on the Detection of Trace Metals in Environmental Water Samples." Sensors 21, no. 1 (December 28, 2020): 131. http://dx.doi.org/10.3390/s21010131.

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The elevated concentrations of various trace metals beyond existing guideline recommendations in water bodies have promoted research on the development of various electrochemical nanosensors for the trace metals’ early detection. Inspired by the exciting physical and chemical properties of nanomaterials, advanced functional nanocomposites with improved sensitivity, sensitivity and stability, amongst other performance parameters, have been synthesized, characterized, and applied on the detection of various trace metals in water matrices. Nanocomposites have been perceived as a solution to address a critical challenge of distinct nanomaterials that are limited by agglomerations, structure stacking leading to aggregations, low conductivity, and limited porous structure for electrolyte access, amongst others. In the past few years, much effort has been dedicated to the development of various nanocomposites such as; electrochemical nanosensors for the detection of trace metals in water matrices. Herein, the recent progress on the development of nanocomposites classified according to their structure as carbon nanocomposites, metallic nanocomposites, and metal oxide/hydroxide nanocomposites is summarized, alongside their application as electrochemical nanosensors for trace metals detection in water matrices. Some perspectives on the development of smart electrochemical nanosensors are also introduced.

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30

Song, Yu, Mingyue Zhang, Tianyu Liu, Tianjiao Li, Di Guo, and Xiao-Xia Liu. "Cobalt-Containing Nanoporous Nitrogen-Doped Carbon Nanocuboids from Zeolite Imidazole Frameworks for Supercapacitors." Nanomaterials 9, no. 8 (August 2, 2019): 1110. http://dx.doi.org/10.3390/nano9081110.

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Pyrolyzing metal–organic frameworks (MOFs) typically yield composites consisting of metal/metal oxide nanoparticles finely dispersed on carbon matrices. The blend of pseudocapacitive metal oxides and conductive metals, as well as highly porous carbon networks, offer unique opportunities to obtain supercapacitor electrodes with mutually high capacitances and excellent rate capabilities. Herein, we demonstrate nitrogen-doped carbon nanocuboid arrays grown on carbon fibers and incorporating cobalt metal and cobalt metal oxides. This composite was synthesized via pyrolysis of a chemical bath deposited MOF, cobalt-containing zeolite imidazole framework (Co–ZIF). The active materials for charge storage are the cobalt oxide and nitrogen-doped carbon. Additionally, the Co metal and the nanoporous carbon network facilitated electron transport and the rich nanopores in each nanocuboid shortened ion diffusion distance. Benefited from these merits, our Co–ZIF-derived electrode delivered an areal capacitance of 1177 mF cm−2 and excellent cycling stability of ~94% capacitance retained after 20,000 continuous charge–discharge cycles. An asymmetric supercapacitor prototype having the Co–ZIF-derived hybrid material (positive electrode) and activated carbon (negative electrode) achieved a maximal volumetric energy density of 1.32 mWh cm−3 and the highest volumetric power density of 376 mW cm−3. This work highlights the promise of metal–metal oxide–carbon nanostructured composites as electrodes in electrochemical energy storage devices.

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Elmanovich, I. V., V. V. Zefirov, V. E. Sizov, M. S. Kondratenko, and M. O. Gallyamov. "Polymer-inorganic composites based on Celgard matrices obtained using solutions of (aminopropyl)triethoxysilane in supercritical carbon dioxide." Доклады Академии наук 485, no. 4 (May 22, 2019): 451–56. http://dx.doi.org/10.31857/s0869-56524854451-456.

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A method has been developed for the fabrication of a polymer-inorganic composite material based on the Celgard polymer matrix by means of the introduction of silica nanoparticles with amino groups into the polymer structure through impregnation of porous structure with solutions of the aminosilane precursor in supercritical СO2. The presence of inorganic nanoparticles made it possible to noticeably enhance the hydrophilicity of the material, and the absolute wetting ability of supercritical CO2 was favorable for uniform particle distribution in membrane pores. The particles growing in membrane pores allowed one to reduce the pore size, which opens ways to control ion-transport selectivity.

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32

Timashev, P. S., N. N. Vorobieva, N. V. Minaev, Yu A. Piskun, I. V. Vasilenko, S. G. Lakeev, S. V. Kostyuk, V. V. Lunin та V. N. Bagratashvili. "Formation of porous matrices from lactide and ε-caprolactone copolymers in supercritical carbon dioxide medium". Russian Journal of Physical Chemistry B 10, № 8 (грудень 2016): 1195–200. http://dx.doi.org/10.1134/s1990793116080078.

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Tomer, Vijay K., Ritu Malik, Jimi Tjong, and Mohini Sain. "State and future implementation perspectives of porous carbon-based hybridized matrices for lithium sulfur battery." Coordination Chemistry Reviews 481 (April 2023): 215055. http://dx.doi.org/10.1016/j.ccr.2023.215055.

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Kaplin, Vladislav, Aleksandr Kopylov, Anastasiia Koryakovtseva, Nikita Minaev, Evgenii Epifanov, Aleksandr Gulin, Nadejda Aksenova, et al. "Features of Luminescent Properties of Alginate Aerogels with Rare Earth Elements as Photoactive Cross-Linking Agents." Gels 8, no. 10 (September 27, 2022): 617. http://dx.doi.org/10.3390/gels8100617.

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Luminescent aerogels based on sodium alginate cross-linked with ions of rare earth elements (Eu3+, Tb3+, Sm3+) and containing phenanthroline, thenoyltrifluoroacetone, dibenzoylmethane, and acetylacetone as ligands introduced into the matrix during the impregnation of alginate aerogels (AEG), were obtained for the first time in a supercritical carbon dioxide medium. The impregnation method used made it possible to introduce organically soluble sensitizing ligands into polysaccharide matrices over the entire thickness of the sample while maintaining the porous structure of the aerogel. It is shown that the pore size and their specific area are150 nm and 270 m2/g, respectively. Moreover, metal ions with content of about 23 wt.%, acting as cross-linking agents, are uniformly distributed over the thickness of the sample. In addition, the effect of sensitizing ligands on the luminescence intensity of cross-linked aerogel matrices is considered. The interaction in the resulting metal/ligand systems is unique for each pair, which is confirmed by the detection of broad bands with individual positions in the luminescence excitation spectra of photoactive aerogels.

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35

Gioti, Christina, Anastasios Karakassides, Georgios Asimakopoulos, Maria Baikousi, Constantinos E. Salmas, Zacharias Viskadourakis, George Kenanakis, and Michael A. Karakassides. "Multifunctional Carbon-Based Hybrid Foams for Shape-Stabilization of Phase Change Materials, Thermal Energy Storage, and Electromagnetic Interference Shielding Functions." Micro 2, no. 3 (July 5, 2022): 390–409. http://dx.doi.org/10.3390/micro2030026.

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Carbon-red mud foam/paraffin hybrid materials were prepared and studied for their thermal energy storage and electromagnetic interference (EMI) shielding properties. The host matrices were prepared utilizing the polymeric foam replication method, with a polyurethane sponge as a template, resin as a carbon source, and red mud as a filler. The paraffins, n-octadecane (OD) and the commercial RT18HC, were used as organic encapsulant phase change materials (PCMs) into the open pore structure of the foams. The foams’ morphological and structural study revealed a highly porous structure (bulk density, apparent porosity P > 65%), which exhibits elliptical and spherical pores, sized from 50 up to 500 μm, and cell walls composed of partially graphitized carbon and various oxide phases. The hybrid foams showed a remarkable encapsulation efficiency as shape stabilizers for paraffins: 48.8% (OD), 37.8% (RT18HC), while their melting enthalpies (ΔHm) were found to be 126.9 J/g and 115.5 J/g, respectively. The investigated hybrids showed efficient electromagnetic shielding performance in frequency range of 3.5–9.0 GHz reaching the entry-level value of ~20 dB required for commercial applications, when filled with PCMs. Their excellent thermal and EMI shielding performance places the as-prepared samples as promising candidates for use in thermal management and EMI shielding of electronic devices as well.

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36

Shah Mohammadi, Maziar, Ehsan Rezabeigi, Jason Bertram, Benedetto Marelli, Richard Gendron, Showan N. Nazhat, and Martin N. Bureau. "Poly(d,l-Lactic acid) Composite Foams Containing Phosphate Glass Particles Produced via Solid-State Foaming Using CO2 for Bone Tissue Engineering Applications." Polymers 12, no. 1 (January 17, 2020): 231. http://dx.doi.org/10.3390/polym12010231.

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This study reports on the production and characterization of highly porous (up to 91%) composite foams for potential bone tissue engineering (BTE) applications. A calcium phosphate-based glass particulate (PGP) filler of the formulation 50P2O5-40CaO-10TiO2 mol.%, was incorporated into biodegradable poly(d,l-lactic acid) (PDLLA) at 5, 10, 20, and 30 vol.%. The composites were fabricated by melt compounding (extrusion) and compression molding, and converted into porous structures through solid-state foaming (SSF) using high-pressure gaseous carbon dioxide. The morphological and mechanical properties of neat PDLLA and composites in both nonporous and porous states were examined. Scanning electron microscopy micrographs showed that the PGPs were well dispersed throughout the matrices. The highly porous composite systems exhibited improved compressive strength and Young’s modulus (up to >2-fold) and well-interconnected macropores (up to ~78% open pores at 30 vol.% PGP) compared to those of the neat PDLLA foam. The pore size of the composite foams decreased with increasing PGPs content from an average of 920 µm for neat PDLLA foam to 190 µm for PDLLA-30PGP. Furthermore, the experimental data was in line with the Gibson and Ashby model, and effective microstructural changes were confirmed to occur upon 30 vol.% PGP incorporation. Interestingly, the SSF technique allowed for a high incorporation of bioactive particles (up to 30 vol.%—equivalent to ~46 wt.%) while maintaining the morphological and mechanical criteria required for BTE scaffolds. Based on the results, the SSF technique can offer more advantages and flexibility for designing composite foams with tunable characteristics compared to other methods used for the fabrication of BTE scaffolds.

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37

Semak, Vladislav, Tanja Eichhorn, René Weiss, and Viktoria Weber. "Polyzwitterionic Coating of Porous Adsorbents for Therapeutic Apheresis." Journal of Functional Biomaterials 13, no. 4 (November 3, 2022): 216. http://dx.doi.org/10.3390/jfb13040216.

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Adsorbents for whole blood apheresis need to be highly blood compatible to minimize the activation of blood cells on the biomaterial surface. Here, we developed blood-compatible matrices by surface modification with polyzwitterionic polysulfobetainic and polycarboxybetainic coatings. Photoreactive zwitterionic terpolymers were synthesized by free-radical polymerization of zwitterionic, photoreactive, and fluorescent monomers. Upon UV irradiation, the terpolymers were photodeposited and mutually crosslinked on the surface of hydrophobic polystyrene-co-divinylbenzene and hydrophilic polyacrylamide-co-polyacrylate (DALI) beads. Fluorescent microscopy revealed coatings with an average thickness of 5 µm, which were limited to the bead surface. Blood compatibility was assessed based on polymer-induced hemolysis, coagulation parameters, and in vitro tests. The maintenance of the adsorption capacity after coating was studied in human whole blood with cytokines for polystyrene beads (remained capacity 25–67%) and with low-density lipoprotein (remained capacity 80%) for polyacrylate beads. Coating enhanced the blood compatibility of hydrophobic, but not of hydrophilic adsorbents. The most prominent effect was observed on coagulation parameters (e.g., PT, aPTT, TT, and protein C) and neutrophil count. Polycarboxybetaine with a charge spacer of five carbons was the most promising polyzwitterion for the coating of adsorbents for whole blood apheresis.

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38

Weinberger, Christian, Jan Roggenbuck, Jan Hanss, and Michael Tiemann. "Synthesis of Mesoporous Metal Oxides by Structure Replication: Thermal Analysis of Metal Nitrates in Porous Carbon Matrices." Nanomaterials 5, no. 3 (August 28, 2015): 1431–41. http://dx.doi.org/10.3390/nano5031431.

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39

Zalepugin, D. Yu, N. A. Tilkunova, E. V. Fronchek, M. O. Gallyamov, I. V. Chernyshova, V. S. Mishin, Yu S. Yashin, T. E. Grigoryev, A. I. Gamzazade, and A. R. Khokhlov. "Production of new haemostatic materials by deposition of dispersed proteins onto porous matrices using supercritical carbon dioxide." Russian Journal of Physical Chemistry B 4, no. 7 (December 2010): 1047–50. http://dx.doi.org/10.1134/s1990793110070018.

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40

Zefirov, V. V., M. A. Pigaleva, V. G. Sergeyev, and M. O. Gallyamov. "Deposition of a Chitosan Coating on Celgard Porous Matrices in the Presence of Carbon Dioxide under Pressure." Polymer Science, Series A 62, no. 2 (March 2020): 123–31. http://dx.doi.org/10.1134/s0965545x20020078.

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41

Poh, Leslie, Christian Della, Shengjie Ying, Cindy Goh, and Yun Li. "Micromechanics model for predicting effective elastic moduli of porous ceramic matrices with randomly oriented carbon nanotube reinforcements." AIP Advances 5, no. 9 (September 2015): 097153. http://dx.doi.org/10.1063/1.4931453.

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42

Sangroniz, Leire, Ainara Sangroniz, Mercedes Fernández, Agustin Etxeberria, Alejandro J. Müller, and Antxon Santamaria. "Elaboration and Characterization of Conductive Polymer Nanocomposites with Potential Use as Electrically Driven Membranes." Polymers 11, no. 7 (July 13, 2019): 1180. http://dx.doi.org/10.3390/polym11071180.

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In this work, a general, facile, and relatively low-cost method to produce electrically driven non-porous membranes by revalorization of recycled polyolefins is proposed. The polymer matrices are poly(propylene) (PP) and poly(ethylene) (PE) and their corresponding recycled samples, which are respectively mixed with carbon nanotubes (CNT). The performances of the elaborated nanocomposites are studied by morphological, rheological, and electrical conductivity tests. The Joule heating effect is evaluated by applying an electric field and recording the corresponding temperature rise. An increase of 90 °C is obtained in certain cases, which represents the highest temperature enhancement reached so far by the Joule effect in thermoplastics, to our knowledge. The work shows a route to develop stimulus (voltage)-response (temperature) materials with low cost and with potential applications in many fields. As an example, the increase of the permeability with temperature of membranes made of the indicated nanocomposites, is analyzed.

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43

Zhang, Hao, Mengru Zhang, Meiling Zhang, Lin Zhang, Anping Zhang, Yiming Zhou, Ping Wu, and Yawen Tang. "Hybrid aerogel-derived Sn–Ni alloy immobilized within porous carbon/graphene dual matrices for high-performance lithium storage." Journal of Colloid and Interface Science 501 (September 2017): 267–72. http://dx.doi.org/10.1016/j.jcis.2017.04.071.

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44

Xie, Li-Sheng, Sheng-Xue Yu, Hui-Jun Yang, Jun Yang, Jian-Lan Ni, and Jiu-Lin Wang. "Hierarchical porous carbon derived from animal bone as matric to encapsulated selenium for high performance Li–Se battery." Rare Metals 36, no. 5 (April 29, 2017): 434–41. http://dx.doi.org/10.1007/s12598-017-0910-0.

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45

Nemets, E. A., A. P. Malkova, G. A. Dukhina, A. E. Lazhko, Y. B. Basok, A. D. Kirillova, and V. I. Sevastianov. "Effect of supercritical carbon dioxide on the in vivo biocompatible and resorptive properties of tissue-specific scaffolds from decellularized pig liver fragments." Perspektivnye Materialy 11 (2021): 20–31. http://dx.doi.org/10.30791/1028-978x-2021-11-20-31.

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The creation of bioengineered tissue/organ equivalents is closely related to the development of biodegradable, highly porous 3D scaffolds, which to some extent provide the microenvironment necessary to maintain the viability of the cellular component. According to many researchers, the most interesting are tissue-specific matrices that can selectively support the adhesion, proliferation and differentiation of tissue cells of those organs from which they are obtained by decellularization. It was shown that during intramuscular implantation in rats of decellularized pig liver fragments (DLFp), independent of the method of detergent residues removing (96 hours of washing in phosphate-salt buffer (PBS) or combined: 24 hours in PBS and 8 hours with supercritical CO2 (sc-CO2), the samples meet the requirements for medical devices in terms of local and general toxic effects. Thus, the use of sc-CO2 made it possible to reduce the duration of the technology for producing biocompatible tissue-specific matrices based on DLFp by 3 times. Moreover, when using sc-CO2 at the stage of washing the DLFp matrix, a “mild reaction” of the tissue to the sample is observed during 2 months of intramuscular implantation of the matrix in rats with its complete resorption after 3 months of the experiment. Under the same conditions, the duration of a similar local action of DLFp washed in the PBS on the tissue is 3 months with degradation of 63% of the matrix of the sample size.

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46

Rybaltovskii, A. O., A. A. Akovantseva, E. N. Bolbasov, V. M. Buznik, Yu S. Zavorotny, N. V. Minaev, A. G. Mirochnik, A. A. Sergeev, S. I. Tverdokhlebov, and V. I. Yusupov. "Highly Porous Fluorescent Materials Based on Polymer Matrices Impregnated with Eu(dbm)3 Molecules in a Supercritical Carbon Dioxide Medium." Russian Journal of Physical Chemistry B 14, no. 7 (December 2020): 1081–89. http://dx.doi.org/10.1134/s1990793120070155.

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47

Wang, Ziqi, Xiang Li, Yu Yang, Yuanjing Cui, Hongge Pan, Zhiyu Wang, Banglin Chen та Guodong Qian. "Highly dispersed β-NiS nanoparticles in porous carbon matrices by a template metal–organic framework method for lithium-ion cathode". Journal of Materials Chemistry A 2, № 21 (2014): 7912. http://dx.doi.org/10.1039/c4ta00367e.

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48

Liu, Wei, Shujuan Tan, Zhihong Yang, and Guangbin Ji. "Hollow graphite spheres embedded in porous amorphous carbon matrices as lightweight and low-frequency microwave absorbing material through modulating dielectric loss." Carbon 138 (November 2018): 143–53. http://dx.doi.org/10.1016/j.carbon.2018.06.009.

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49

Eyni, Hossein, Sadegh Ghorbani, Reza Shirazi, Leila Salari Asl, Shahram P Beiranvand, and Masoud Soleimani. "Three-dimensional wet-electrospun poly(lactic acid)/multi-wall carbon nanotubes scaffold induces differentiation of human menstrual blood-derived stem cells into germ-like cells." Journal of Biomaterials Applications 32, no. 3 (July 28, 2017): 373–83. http://dx.doi.org/10.1177/0885328217723179.

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Infertility caused by the disruption or absence of germ cells is a major and largely incurable medical problem. Germ cells (i.e., sperm or egg) play a key role in the transmission of genetic and epigenetic information across generations. Generation of gametes derived in vitro from stem cells hold promising prospects which could potentially help infertile men and women. Menstrual blood-derived stem cells are a unique stem cell source. Evidence suggests that menstrual blood-derived stem cells exhibit a multi-lineage potential and have attracted extensive attention in regenerative medicine. To maintain the three-dimensional structure of natural extra cellular matrices in vitro, scaffolds can do this favor and mimic a microenvironment for cell proliferation and differentiation. According to previous studies, poly(lactic acid) and multi-wall carbon nanotubes have been introduced as novel and promising biomaterials for the proliferation and differentiation of stem cells. Some cell types have been successfully grown on a matrix containing carbon nanotubes in tissue engineering but there is no report for this material to support stem cells differentiation into germ cells lineage. This study designed a 3D wet-electrospun poly(lactic acid) and poly(lactic acid)/multi-wall carbon nanotubes composite scaffold to compare infiltration, proliferation, and differentiation potential of menstrual blood-derived stem cells toward germ cell lineage with 2D culture. Our primary data revealed that the fabricated scaffold has mechanical and biological suitable qualities for supporting and attachments of stem cells. The differentiated menstrual blood-derived stem cells tracking in scaffolds using scanning electron microscopy confirmed cell attachment, aggregation, and distribution on the porous scaffold. Based on the differentiation assay by RT-PCR analysis, stem cells and germ-like cells markers were expressed in 3D groups as well as 2D one. It seems that poly(lactic acid)/multi-wall carbon nanotubes scaffold-seeded menstrual blood-derived stem cells could be viewed as a novel, safe, and accessible construct for these cells, as they enhance germ-like generation from menstrual blood-derived stem cells.

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Ghelich, Raziyeh, Rouhollah Mehdinavaz Aghdam, and Mohammad Reza Jahannama. "Elevated temperature resistance of SiC-carbon/phenolic nanocomposites reinforced with zirconium diboride nanofibers." Journal of Composite Materials 52, no. 9 (September 14, 2017): 1239–51. http://dx.doi.org/10.1177/0021998317723447.

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Carbon fiber-reinforced composites with matrices containing ultra-high temperature ceramics show excellent potential as high ablation-resistant materials. In this study, two non-oxide nanostructures, ZrB2 nanofibers and SiC nanoparticles, as reinforcement phases were utilized to develop the carbon/phenolic-ZrB2-SiC (C/Ph-ZS) nanocomposite for the first time. Thermogravimetry analysis illustrated that the residue yield of C/Ph composite at high temperatures was increased by the introduction of above-mentioned nanostructure ceramics. The addition of 7 wt% of ZrB2/SiC nanoadditives homogeneously in a C/Ph composite resulted in an enhancement of the room temperature thermal diffusivity, from 0.00622 to 0.00728 cm2/s. The incorporation of 4–7 wt% of ZrB2/SiC nanofillers in C/Ph composites leads to a reinforced material with about 73% increasing of Shore D hardness. The modified thermal behavior of prepared nanocomposites was examined using oxyacetylene torch at 2500℃ for 160 s. It suggested that the C/Ph-ZS7% nanocomposites with lower density may drastically contribute to meliorate the thermal insulation and ablative properties. The linear ablation rates of C/Ph composites were decreased after adding 7 wt% ZrB2/SiC nanofillers by 18%. The formation of a dense and uniform SiO2 and ZrO2 layer on the ablated surface of C/Ph-ZS nanocomposites could function as an effective oxygen barrier which greatly reduced the ablation rates of the nanocomposites because of the evaporation at elevated temperature, which absorbs heat from the flame and reduces the erosive attack to C/Ph. The ablated C/Ph-ZS nanocomposite with complicated cross-section structure displayed four dense oxidized, porous surface, transient and matrix regions.

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