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Geopolymers, composed of an amorphous three-dimensional inorganic network and synthesized by the activation of a solid alumino-silicate precursor with an alkaline activating solution, have attracted increasing attention because of their environmental benefits and favorable characteristics. This review deals with the development of organic/inorganic composite materials made by adding organic liquids into inorganic geopolymer matrices. Firstly, the incorporation processing approaches are presented and are divided into three categories: (i) Direct incorporation, (ii) Pre-emulsification (iii) Solid impregnation. Their main advantages and drawbacks are discussed in relation to the aimed properties. Secondly, this review highlights that geopolymers are low-cost candidates allowing technologically significant applications, through the incorporation of various organic liquids. Aside from the well-studied immobilization of industrial waste streams commonly known as stabilization/solidification (S/S), the development of highly porous geopolymer foams and the design of reinforced organic/inorganic composite matrices are being notably investigated. This review aims at summarizing the main published results, and fostering further investigations into innovative uses of organic liquids incorporated into geopolymers for a wide range of applications.

By reverse codeposition of hydroxides, highly dispersed powder (the average size of 8–10 nm) of the composition (ZrO2)0.92(Y2О3)0.03(СеО2)0.05 is synthesized; on the basis of it, with use of a comprehensive a blowing agent and mechanical activation, a highly porous ceramic (average grain size of 60–65 nm) is obtained. The synthesized ceramic material—an implant with an open porosity of 55% and a pore size of 40–800 nm—was placed in the body of laboratory animals. The reaction of biological tissues of experimental animals to the introduction of plates made of composite highly porous materials based on t-ZrO2 15 months after their implantation was studied. It is revealed that enhanced revascularization is registered in capsules, and perfusion of tissues is registered in the intact zone of ceramic introduction. The possibility of germination of vessels in soft tissues into the available pore space of the ceramic is shown. The results obtained in vivo suggest that porous bioceramics based on t-ZrO2 can be used in the production of endoprostheses and implants in such areas of medicine as orthopedics and traumatology.

In recent years there is a high interest in the freeze-casting process because it is a simple, economical, and environmentally friendly method for obtaining highly porous materials. Most of the materials obtained by this technique have directional pore structure and anisotropic properties. However, a wide range of pore size and morphology can be obtained by the control of processing parameters, such as solvent type, solids concentration, particle size, freezing rate, and types of additives. The varied morphologies permit the application of freeze-casted materials in various technological applications. However, despite the high amount of studies about freeze-casting of ceramic materials in the last years, review articles addressing the influence of processing parameters on the pore characteristics of obtained ceramics are still scanty. Therefore, this review addresses the influence of freeze-casting process parameters on the pore characteristics of the ceramic materials.

Highly porous aluminum alloys and honeycomb structures may be utilized as single-use shock absorbers in landing gear and other elements of spacecraft thus ensuring safety of the landing process. This paper presents the results of studies that make it possible to estimate mechanical properties and shock-absorbing characteristics of highly porous aluminum alloys and honeycomb aluminum alloy structures, the initial average densities of said alloys and structures ranging from 330 to 2250 kg/m³. We list analogs that correspond with different stages found on stress-strain curves of highly porous aluminum alloys and honeycomb structures. The paper also provides the foundations of calculating the specific and effective energies of shock absorption.

Severe acetabular bone defects during revision total hip arthroplasty are often treated with a hemispherical shell and highly porous modular metal augments. Several papers have been already published reporting on the clinical performance of trabecular metal (TM) augments combined with a hemispherical shell for the management of severe acetabular defects. However, no systematic review of the literature has been published to date. The U.S. National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews were queried for publications utilizing keywords pertinent to tantalum augments and TM (Zimmer Biomet, Warsaw, Indiana) augments, revision THA, clinical outcomes, and complications associated with these procedures. Fifteen articles were found to be suitable for inclusion in the present study, which included 769 revision cases where acetabular augments were used. The majority of acetabular bone defects were type 3 according to the Paprosky classification (type 2A in 58 cases, 7.2%; type 2B in 139 cases, 17.2%; type 2C in 72 cases, 8.9%; type 3A in 360 cases, 44.7%; and type 3B in 177 cases, 22.0%). The overall revision rate for the 769 acetabular revisions with augments was 5.7% (46 cases) at mean mid-term follow-up. The most common reasons for revision were dislocation (3.3%), periprosthetic joint infection (2.9%), and aseptic loosening (2.7%). TM augments combined with hemispherical shells were found to be effective in the treatment of moderate-to-severe acetabular bone defects with a 5% acetabular component revision rate at mean mid-term follow-up. The literature did not delineate whether pelvic discontinuity was associated with a higher risk of aseptic loosening after TM augment. Further studies are needed to clarify the impact of additional screw fixation on survival rates, and whether the type of augment (wedge augments, “flying buttress” augments, column augments), the configuration used, and the number of screws influence clinical and radiographic outcomes.

Fabricating a porous scaffold with high surface area has been a major strategy in the tissue engineering field. Among the many fabrication methods, electrospinning has become one of the cornerstone techniques due to its enabling the fabrication of highly porous fibrous scaffolds that are of natural or synthetic origin. Apart from the basic requirements of mechanical stability and biocompatibility, scaffolds are further expected to embody functional cues that drive cellular functions such as adhesion, spreading, proliferation, migration, and differentiation. There are abundant distinct approaches to introducing bioactive molecules to have a control over cellular functions. However, the lack of a thorough understanding of cell behavior with respect to the availability and spatial distribution of the bioactive molecules in 3D fibrous scaffolds is yet to be addressed. The rational selection of proper sets of characterization techniques would essentially impact the interpretation of the cell-scaffold interactions. In this timely Review, we summarize the most popular methods to introduce functional compounds to electrospun fibers. Thereafter, the strength and limitations of the conventional characterization methods are highlighted. Finally, the potential and applicability of emerging characterization techniques such as high-resolution/correlative microscopy approaches are further discussed.

Herein, we report a synthesis method for highly porous molybdenum oxide via molybdenum-oxo cluster formation under acidic conditions providing extraordinary stability. Synthesized materials indicat...

Highly porous Co3O4/NiCo2O4 nanostructures were synthesized using zeolitic imidazolate framework-67 (ZIF-67) nanocrystals. The oxide composite structure was adjusted by modifying ZIF-67 crystallite...

A novel nanoparticle‐polymer composite is proposed, named inverse nanocomposites in this work. First, a rigid percolating scaffold of nanoparticles is formed, which is filled with a matrix and then polymerized. Targeted for use in thin‐film applications, these mesoporous nanoparticle scaffolds are prepared by combining the sol–gel chemistry of functionalized silanes with nanoparticles in dispersions. The nanoparticle coatings have high porosity, low density, good adhesion to the substrate, and interesting non‐classical properties, such as absorbency of highly viscous fluids. The porosity, which can be adjusted by changing the composition and preparation parameters, reaches 75%. The porous scaffold can be infiltrated with various fluids, including acrylic and epoxy monomers and even highly viscous pressure‐sensitive adhesives. If the monomers are polymerized after imbibition, the inverse nanocomposite is formed, consisting of a percolating particle network surrounded by a polymeric binder. Hence, the morphology comprises an interpenetrating system of two co‐continuous phases and not merely particles dispersed in a polymeric phase, as is typical for conventionally prepared nanocomposites.

The uniaxial compressive strength (UCS) of intact rock is one of the most important parameters required and determined for rock mechanics studies in engineering projects. The limitations and difficulty of conducting tests on rocks, specifically on thinly bedded, highly fractured, highly porous and weak rocks, as well as the fact that these tests are destructive, expensive and time-consuming, lead to development of soft computing-based techniques. Application of artificial neural networks (ANNs) for predicting UCS has become an attractive alternative for geotechnical engineering scientists. In this study, an ANN was designed with the aim of indirectly predicting UCS through the serpentinization percentage, and physical, dynamic and mechanical characteristics of serpentinites. For this purpose, data obtained in earlier experimental work from central Greece were used. The ANN-based results were compared with the experimental ones and those obtained from previous analysis. The proposed ANN-based formula was found to be very efficient in predicting UCS values and the samples could be classified with simple physical, dynamic and mechanical tests, thus the expensive, difficult, time-consuming and destructive mechanical tests could be avoided.

A novel biobased and highly porous aerogel was fabricated by cross-linking between chitosan (CS) and cellulose nanofibrils (CNFs). The structural and chemical characteristics of the produced CS/CNF...

A highly porous metal–organic framework (MOF) based on the Cu(II) ion, {[Cu6(TATAB)4(DABCO)3(H2O)3]·24DMF}n (Cu(II)-MOF) (where H3TATAB = 4,4′,4″-s-triazine-1,3,5-triyl-tri-p-aminobenzoic acid and ...

This study aimed to prepare and characterise polylactic acid (PLA) reinforced with cellulose nanofibre (CNF) from a Pennisetum purpureum-based composite scaffold and determine its structural and mechanical properties. Porous scaffolds with CNF compositions of 5‒20 wt% in the PLA matrix were developed using solvent casting and particulate leaching of its porogen at 90 wt% of loadings. Morphology studies using field emission scanning electron microscopy revealed that the scaffolds had well-interconnected pores with an average pore size range of 67‒137 µm and porosity >76%. X-ray diffraction confirmed the interconnectivity and homogeneity of the pores and the fibrous structure of the scaffolds. The compressive strength of the fabricated scaffolds varied between 2.34 and 6.66 MPa, while their compressive modulus was between 1.95 and 6.04 MPa for various CNF contents. Furthermore, water absorption and thermal degradation studies showed that the scaffold had good hydrophilicity and improved thermal stability. These findings highlight the need to modify the pore structure and mechanical performance simultaneously for tissue engineering. Thus, this study concludes that the developed PLA scaffolds reinforced with CNF from Pennisetum purpureum are potential candidates for cell attachment and extracellular matrix generation.

The paper considers the structural and physical characteristics of carriers based on ceramic highly porous block materials of a cellular structure, which provide the sorption-filtering properties of contact elements. Methods for determining the external specific volumetric surface, gas-dynamic resistance and gas permeability are described. Their interrelation and optimal combination with the operational characteristics of sorbent filters in the processes of capturing volatile compounds of iodine and cesium in gas streams is shown. The results obtained can be used to synthesize contact elements of a new class and create on their basis highly efficient gas cleaning systems operating at high temperatures and corrosive environments.

Due to the fascinating features such as ultra-thickness, great surface-to-volume atom ratios, abundantly available unsaturated coordination sites, highly porous structure, enhanced conductivity, and easily tunable structure, considerable research interest in the area of 2D metal–organic framework nanosheets (2D MONs) has been aroused worldwide. In this review, some recent contributions in 2D MONs by adopting various top-down (sonication exfoliation, chemical exfoliation, mechanical exfoliation, Li-intercalation, and chemical-assisted approach) and bottom-up strategies (surfactant-assisted approach, interfacial synthesis, modulated method, sonication synthesis) are summarized. This work aims to summarize some basic characterization techniques adopted for analyzing the developed 2D MONs. In further sections, promising applications of 2D MONs in various fields such as catalysis, gas separation, energy storage and conversion, sensors, wastewater treatment and biomedicine are also presented. In the final section, the exclusive perception of challenges and futuristic possibilities in order to promote development in this research field are presented.

Micromotors possessing a self-propulsion system have been proposed as a new generation of advanced materials for various environmental applications. Due to their actively moving properties, micromotors can significantly improve the operational efficiency of typical environmental remediation (e.g., adsorption and photocatalysis) as well as the dynamic sensing of typical pollutants. The cargo or propellant-loading capability of micromotors can be enhanced by increasing the specific surface area. In this regard, highly porous metal–organic frameworks (MOFs) can be ideal candidates for micromotors with efficient autonomous motion capabilities. Hence, integration of MOFs into micromotors can provide a multitude of new opportunities for specific but uncharacterized applications. However, MOF micromotors remain in their infancy despite exploration on a wide variety. The present study aimed to briefly review the few cases of MOF micromotors reported in the literature with regard to environmental applications. The broader objective was to highlight the remarkable potential of MOF micromotor systems to motivate and increase new research at the intersection of environmental and material engineering.

Geological conditions (presence of highly porous, fractured and cavernous rocks in the section) and technological parameters have a significant impact on the occurrence of various complications during well construction. The most frequent complications, which are recorded in almost all oil and gas provinces, include absorption of flushing fluid (circulating drilling fluid). In the process of uncovering the rocks composing the section, their equilibrium is disturbed. As you know, the stability of rocks depends on their strength characteristics, change over time under the influence of various factors: tectonic movements, secondary processes (leaching, dolomitization, calcification), opening of mine workings. Geoecological risks arise in the presence of fractured, cavernous and highly porous formations in the geological section, zones of tectonic fracturing, faults and traps (Eastern Siberia). These risks are expressed in absorption of flushing fluid used during construction of wells; rock falls, water and oil and gas occurrences, open fountains. Scientific novelty. In order to prevent these complications it is necessary to correctly select recipe of used flushing fluids, their treatment with different chemical reagents. Among technological factors causing geological risks one may mention high density of circulating and cementing solutions, speed of their pumping, rheological properties, lowering-raising operations, violation of technological mode and others. Conclusions . Absorption elimination is carried out by colmatation of complication intervals with solid particles (colmatants), special inert fillers, plugging mixtures, reduction of solution density, installation of cement bridges, which do not always give positive results.

Herein, we have developed a Cr3+ doped Al2O3 of a hierarchical nanostructure by a simple two-step synthesis. A pure AlO(OH)⋅αH2O, as synthesized in forms of small tubular fibers by hydrolysis of Al-metal sheets, is easily doped with selective Cr3+ dosages up to 2.0 mol% using an aqueous CrO3. As-synthesized samples exhibit XRD of a single phase Cr3+: Al2O3 of a rhombohedral crystal structure. Average pore-volume is decreased as 98.1, 89.8, and 61.5 cm3-g-1 in the 0.5, 1.0 and 2.0 % Cr% doped samples, with average pore radius of 1.70, 2.17 and 1.90 nm, respectively, as measure from BET specific surface area. Local Al-O vibrations exhibit IR bands of 400 to 1200 cm-1 intrinsic of oxygen polygons. At room temperature, a duly tailored dielectric permittivity of 480 is obtained in a 2.0 mol% Cr3+:Al2O3 and that is enhanced progressively on heating it over 25 to 300 °C, showing a value 6700 at 300 °C in phonon induced dynamics of charge carriers, useful for solid-state electronics.

Despite the accessibility to porous architectures through various biofabrication approaches for tissue engineering, incorporating various active growth regulators within their matrices that act as biochemical cues is also an essential attribute for effective tissue growth. To address these facts, icariin (ICA)-encapsulated polymeric scaffolds are fabricated using a low-temperature extrusion-based three-dimensional (3D) printing technology for efficiently promoting osteogenesis. This approach not only resulted in the generation of porous architectures but also substantially maintained the bio-efficacy of the encapsulated ICA. Moreover, these composite scaffolds based on poly(e-caprolactone) (PCL) and tricalcium phosphate (β-TCP) encapsulated with ICA (ITP scaffolds) are systematically characterized using various techniques before and after printing. Furthermore, various investigations relevant to biodegradability, biocompatibility, ICA release, and osteogenic ability of the ITP scaffolds are explored. The intact physiochemical properties of the materials, sustained release of ICA from the scaffolds, and high biosafety at various levels ranging from cellular to animal efficiently promoted the proliferation of mouse bone marrow mesenchymal stem cells (BMSCs) and their differentiation to osteoblasts. Together, the utilization of low-temperature extrusion approach provides a convenient and eco-friendly means of fabricating highly porous 3D architectures that supply the required growth regulators in their active form for tissue regeneration.

Herein, a novel pathway to prepare a porous structured DNA hybrid hydrogel has been described, using a transiently existing Pickering emulsion that is continuously generated during the reaction. The as-prepared highly porous gel features significantly improved capability for trace amounts of PAH removal.

Fe/N/C full of ultrafine Fe-based species and pores is synthesized by pyrolyzing a g-C3N4-coordinated Fe matrix embedded in carbon for oxygen reduction. Enhanced oxygen reduction activity is observed on Fe/N/C with higher pore volume and the Fe/N/C catalyst with the largest pore volume shows the highest half-wave potential of 0.890 V.

Anionic metal–organic frameworks (MOFs) with a negatively charged framework have attracted extensive attention for their potential applications in organic dye adsorption and separation. However, the rational synthesis of anionic MOFs with tunable channel size is still difficult. In this work, two pillar-layered MOFs, namely [(CH3)2NH2]2[Zn4(BTC)2TCPB]·3DMF·H2O (JOU-44) and [(CH3)2NH2]2[Zn4(BPTC)2TCPB]·12DMF·6H2O (JOU-45), were solvothermally synthesized by using a reticular chemistry strategy (H3BTC = 1,3,5-benzenetricarboxylic acid; H3BPTC = [1,1′-biphenyl]-3,4′,5-tricarboxylic acid; H4TCPB = 1,2,4,5-tetrakis(4-carboxyphenyl)benzene). Structural analyses show that JOU-44 and JOU-45 show an isoreticular three-dimensional anionic framework based on [Zn2(COO−)5]− clusters. It should be noted that the pillar-layered framework of JOU-44 is expanded by adjusting the length of the ligands in the layer part, which is different from the pillar extension method reported in the literature. Due to its anionic and highly porous framework, JOU-44 was exploited for adsorption and chromatographic separation of organic dyes. In addition, JOU-44 was also developed as an antenna to selectively sensitize EuIII ions. This work provides a new clue for constructing pillar-layered MOFs with an extensible structure, as well as a new way to extend the applications of MOFs in separation and fluorescence.

The Dawn mission found that the dominant colour variation on the surface of dwarf planet Ceres is a change of the visible spectral slope, where fresh impact craters are surrounded by blue (negative spectral-sloped) ejecta. The origin of this colour variation is still a mystery. Here we investigate a scenario in which an impact mixes the phyllosilicates present on the surface of Ceres with the water ice just below. In our experiment, Ceres analogue material is suspended in liquid water to create intimately mixed ice particles, which are sublimated under conditions approximating those on Ceres. The sublimation residue has a highly porous, foam-like structure made of phyllosilicates that scattered light in similar blue fashion as the Ceres surface. Our experiment provides a mechanism for the blue colour of fresh craters that can naturally emerge from the Ceres environment., The origin of blue ejecta around the fresh craters of dwarf planet Ceres is unknown. Here, the authors show that the blue color results from high porosity of the surface, induced by sublimation of ice-phyllosilicate mixture produced by impacts.

Physical and chemical activation mechanisms of carbon materials are investigated. Uniformly sized spherical carbon particles (SCs) are preferentially synthesized using a modified Stober method and activated under various activation conditions. To elucidate the activation mechanisms, we carefully examine changes in the morphologies, physical properties, and crystallinities of the SCs due to activation under each set of conditions. In addition, we apply the activated SCs (ASCs) to electrode materials for electric double-layer capacitors, and double-check the characteristics of the ASCs from confirmation of their electrochemical properties. Physical carbon activation mainly proceeds via the non-selective removal of carbon from the SC surfaces. Various reactions occurring within the carbon particles during chemical activation selectively remove non-graphitic parts. In the case of the physical activation method, a high activation temperature is required to obtain highly porous carbon with a large surface area. Thus, a relatively high degree of burn-off is inevitable. In contrast, chemical activation at comparatively low temperatures rapidly converts the SCs into highly porous activated carbon. Furthermore, crystallinity is gradually enhanced by the selective removal of non-graphitic parts at higher activation temperatures. Based on these results, we are able to propose mechanisms for the physical and chemical activation of carbon materials.

Conjugated porous polymers through the emulsion-templating polymerization process are typically prepared as monoliths, and the emulsions are cured via metal-catalyzed cross-coupling reactions. Herein, we report the design and synthesis of well-defined, millimeter-sized conjugated porous polymer beads by combining an oil-in-oil-in-oil (O/O/O) double emulsion as a de novo template and an amino-catalyzed Knoevenagel condensation reaction as a polymerization chemistry to cure such emulsions. The 1,4-phenylenediacetonitrile is reacted with aromatic multialdehydes in the presence of piperidine, and a series of metal-free poly(arylene cyano-vinylene) beads are prepared. All beads exhibit 3D-interconnected microcellular morphology and substantial semiconducting properties, such as strong light harvesting ability in the visible light region with electrochemical band gaps in the range of 2.05-2.33 eV. Finally, the promising photocatalytic activity of these conjugated beads is demonstrated for a model sulfoxidation reaction under visible light irradiation, and near quantitative conversions with excellent chemoselectivities (99%) are obtained.

In the selective laser melting of Ti6Al4V powder, the parameters ensuring the required microstructure of highly porous cellular materials are determined. Experimental data regarding the melting of connectors permit specification of the conditions ensuring the formation of a stable cellular framework with complete melting of the center of the connectors and minimum longitudinal and transverse microporosity.

Работа посвящена получению полимера путем сшивки ароматических фрагментов молекул-мономеров с помощью реакции Фриделя-Крафтса. В ходе работы впервые был синтезирован полимер с высокой удельной площадью поверхности (705 м/г) с применением в качестве мономеров бензола и нафталина. Полученный ароматический полимер в дальнейшем может использоваться в качестве носителя для создания катализаторов гидрирования. This work is devoted to the polymer synthesis by crosslinking of aromatic fragments of monomer molecules using Friedel-Crafts reaction. In the framework of this work, a polymer with a high specific surface area (705 m/g) was synthesized for the first time using benzene and naphthalene as monomers. The resulting aromatic polymer can be used as a support for the development of hydrogenation catalysts.

Highly porous zirconium-based metal–organic frameworks (MOFs) have been widely studied as materials for sorption and destruction of chemical warfare agents (CWAs). It is important to understand the...

Structural optimization of activated carbon (AC) mainly relies on experience, which depends on the intrinsic structure of biochar, processing conditions, and the interplay of both parties. A fundam...

We report a facile method to fabricate highly porous, elastic poly(butyl acrylate) (PBA)-based foams with excellent oil absorption capacity, anti-fouling property, and reusability templated by wate...

Background Tantalum components have gained popularity for the management of Paprosky type IIIA and IIIB defects during revision total hip arthroplasty. Although the use of antiprotrusio cages solely shows suboptimal results, there are certain defects that still require their use. We hypothesized that combining tantalum augments and an antiprotrusio cage would (1) improve radiographic stability, (2) enhance survivorship, (3) decrease complications, and (4) improve clinical outcomes. Methods We retrospectively reviewed 20 patients with Paprosky type IIIA or IIIB defects who underwent revision of the acetabular component with a highly porous tantalum augment and an antiprotrusio cage combination. Preoperative and postoperative radiographs, survivorship free from aseptic component revision, and the Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, and Short Form-36 scores were analyzed. The mean follow-up was 2.8 years. Results At the most recent follow-up, no antiprotrusio cages had migrated and all tantalum augments had radiographic evidence of osseointegration. In addition, only 2 components were revised for aseptic etiologies and only 1 was loose. Both were revised secondary to failures of the inferior flange of the antiprotrusio cage. All clinical outcome scores significantly improved postoperatively. Finally, the risk of major postoperative complications was noted to be 10%. Conclusions In summary, a tantalum augment combined with an antiprotrusio cage in Paprosky IIIA and IIIB defects with divergent anatomy not amenable to a hemispherical socket provides a reliable technique to restore the anatomic hip center and prevent superior migration and provides a bony ingrowth surface. Longer term follow-up is required before the technique is widely adapted. Level of Evidence Level IV, therapeutic studies.

Background The ability to utilize magnetic resonance imaging (MRI) to assess bony fixation in 3 dimensions may allow a better understanding of the implant design and bony integration. We hypothesized that a new 3-dimensionally printed cementless highly porous acetabular component (Stryker Trident II TritaniumTM) would show better fixation than an earlier cup from the same manufacturer as assessed by the noninvasive technique of multispectral MRI. Methods Multiacquisition variable-resonance image combination selective metal suppression MRI was performed in 19 patients implanted with a new 3-dimensionally printed cup and 20 patients who had received a previous-generation cup from the same manufacturer at 1-year follow-up. Each cup was graded globally as well as by 9 specific zones. Integration grades were performed for each zone: 0, full bone integration; 1, fibrous membrane present; 2, osteolysis; and 3, fluid present. A mixed-effects logistic regression model was used to compare fixation between the 2 groups. Results All cups in both cohorts showed greater than 90% radiographically estimated global bony integration (3-dimensionally printed cups, 99.4%; regular cups 91.6%) with no osteolysis or fluid observed in any cup. The 3-dimensionally printed cup had 1 of 171 zones (0.6%) graded as fibrous membrane present, while the 2-dimensional group had 15 of 180 zones (8.3%) graded as fibrous. Of note, screw hole regions were omitted but may be read as fibrous membrane areas. Conclusion Using multiacquisition variable-resonance image combination selective MRI, our analysis showed greater biologic fixation and less fibrous membrane formation in the 3-dimensionally printed cups than the control group at 1-year follow-up.

Magnesium silicide (Mg2Si) is one of the few thermoelectric materials that is composed of high Clark number elements and exhibits an optimum temperature near 700 K. The advantage of Mg2Si is that i...

Hybrid composite hydrogels were synthesized by immobilization of 1,10-phenanthrocyanine zinc(II) complex in cellulose hydrogels. The hydrogels exhibited long-term stability, high water retaining capacity and porosity, which were determined using chemical methods. They were characterized with wide-angle X-ray scattering (WAXS), Fourier transform infrared spectroscopy (FTIR), high-resolution solid-state 13C CP/MAS NMR spectroscopy and scanning electron microscopy (SEM). According to FTIR analysis, the immobilization of the complex in the hydrogels led to its interaction with the cellulose inside the matrices of the hydrogels. Additional crystallization of the cellulose in the hydrogels occurred during the formation of the composite hydrogels, as revealed with WAXS. The surface and morphology of the cross-sections of the hydrogels, as well as the pore distribution and pore size, were defined with SEM. The SEM study also ascertained the impact of the molecular mass of the embedded complex on the efficiency of the immobilization.

Sustainable production of a capacitive carbon electrode manifesting notable performance attributed to its honeycomb‐like pore structure for symmetric supercapacitor.

Nanotechnology is a growing technology that has been recognized as vital and scientific with bioprocess development especially in dealing with usage of free cells. Limitations such as low bioavailability, storage instability and low substrate inhibition bound the application of free cells in various field thus leading researchers into focusing more on free cells immobilization system. With the increasing knowledge in nanomaterials fabrication techniques, the immobilization of free cells through entrapment approach in highly porous and the high surface area of nanofibers is becoming an interesting subject to be highlighted. The production of free cells entrapped in nanofibers via electrospinning in terms of quality and quantity is highly affected by the electrospinning operating parameters including solution formulation, ambient conditions, operating conditions of electrospinning machine and types of materials used. Hence, this review paper will provide an overview of the operating conditions involved in electrospinning of cells through entrapment process which affect the characteristics of the electrospun nanofibers produced and the viability or growth of cells when entrapped in the electrospun nanofibers mats.

Storage of natural gas in highly porous materials provides a safer and more energy-efficient solution to energy-intensive compression and liquefaction options for advancing natural gas vehicular sy...

Nanocellulose-based foams are widely used as absorbents due to their highly porous networks and large surface areas. However, their inherent hydrophilicity and poor wet resilience limit their appli...

It is proposed that highly porous coatings on acetabular components, such as a porous tantalum coating, provide adequate fixation without ancillary screw fixation in primary total hip arthroplasty (THA). However, tantalum acetabular components have been associated with higher rates of revision than other uncemented components in national registries. The aim of this randomized controlled trial is to determine whether the early migration of a solid-backed tantalum acetabular component was no greater than that of a titanium acetabular component with ancillary screw fixation that has proven good clinical results.Sixty-six patients aged 40 to 64 years, with osteoarthritis and Charnley grade A or B activity grade and who underwent primary THA, were recruited into the trial. Patients were randomized intraoperatively to receive either the tantalum or titanium acetabular component. All patients received the same cemented polished tapered femoral stem, 28-mm cobalt-chromium femoral head, and highly cross-linked polyethylene liner. Acetabular component migration was measured using radiostereometric analysis at 4-6 days postoperatively and at 6 weeks, 3 months, 1 and 2 years following THA.The mean proximal migration at 2 years for the tantalum cohort was 0.17 mm (95% confidence interval, 0.09-0.24) which was no greater than that of the titanium cohort which was 0.19 mm (0.07-0.32). Harris hip scores and functional activity scores were similar between groups.These results demonstrate that early stability can be achieved without ancillary screw fixation through the use of a highly porous high friction coating on a solid-backed modular acetabular component.Level I.

Hierarchical, conductive, porous, three-dimensional (3D) carbon networks based on carbon nanotubes are used as a scaffold material for the incorporation of sulfur in the vapor phase to produce carbon nanotube tube/sulfur (CNTT/S) composites for application in lithium ion batteries (LIBs) as a cathode material. The high conductivity of the carbon nanotube-based scaffold material, in combination with vapor infiltration of sulfur, allows for improved utilization of insulating sulfur as the active material in the cathode. When sulfur is evenly distributed throughout the network via vapor infiltration, the carbon scaffold material confines the sulfur, allowing the sulfur to become electrochemically active in the context of an LIB. The electrochemical performance of the sulfur cathode was further investigated as a function of the temperature used for the vapor infiltration of sulfur into the carbon scaffolds (155, 175, and 200 °C) in order to determine the ideal infiltration temperature to maximize sulfur loading and minimize the polysulfide shuttle effect. In addition, the nature of the incorporation of sulfur at the interfaces within the 3D carbon network at the different vapor infiltration temperatures will be investigated via Raman, scanning electron microscopy/energy dispersive X-ray, and X-ray photoelectron spectroscopy. The resulting CNTT/S composites, infiltrated at each temperature, were incorporated into a half-cell using Li metal as a counter electrode and a 0.7 M LiTFSI electrolyte in ether solvents and characterized electrochemically using cyclic voltammetry measurements. The results indicate that the CNTT matrix infiltrated with sulfur at the highest temperature (200 °C) had improved incorporation of sulfur into the carbon network, the best electrochemical performance, and the highest sulfur loading, 8.4 mg/cm2, compared to the CNTT matrices infiltrated at 155 and 175 °C, with sulfur loadings of 4.8 and 6.3 mg/cm2, respectively.

In this study, a herbal infused oil (Hypericum perforatum, HP) incorporated chitosan (CS) cryogel as a wound dressing material was produced in order to be used in wound healing process. The main strategy is to combine the traditional perspective of using medicinal oils with polymeric scaffolds manufactured by an engineering approach to fabricate a potential tissue engineering product that provides both new tissue formation and wound healing. The scaffolds manufactured by cryogelation were soft, spongy, highly porous, physically stable, elastic and could be easily cut in any desired shape. Physicochemical, mechanical and morphological analyzes were used to characterize the produced cryogels. Young modulus of the plain chitosan cryogel was about 21 kPa whereas it increased with increasing HP oil content and became 61 kPa for 20% HP oil ratio. Further, the antimicrobial studies, antioxidant and DNA cleavage effects were investigated. Samples including the highest ratio of oil (CS4) showed the highest DPPH scavenging activity as 69.9%. In addition, 20% HP oil loaded chitosan cryogel demonstrated single strain DNA cleavage activitiy at 500 μg/mL concentration. Antimicrobial studies were applied against seven strains. The lowest activities were obtained against E. hirae and B. cereus, the highest against E. coli and L. pneumophila. This study concluded that the newly developed HP oil loaded chitosan cryogel scaffolds with unique antimicrobial and antioxidant properties are promising candidates to be used in tissue engineering applications as wound dressing for exudative and long-term healing wounds.

Highly porous nickel–aluminum oxide aerogels were prepared according to a one-pot sol–gel process and dried under supercritical carbon dioxide conditions. Although the surface properties of these materials were very appealing for applications in catalysis, these aerogels were never applied in adsorption. The nickel effect on the structure and surface properties of the aerogels has been investigated via a broad range of structural, textural, and morphology characterization of the aerogels before and after heat treatment. The adsorption capacity of the as-synthesized and calcined aerogels for azo dyes was assessed under various experimental conditions. The presence of nickel in the aerogel boosts tremendously the surface reactivity and improves noticeably the adsorption capacity of the material. The adsorption capacities for the nickel–aluminum oxide aerogel with 40% nickel (qmax) are 900 mg g–1 for methyl orange, 1484 mg g–1 for orange II, and 1660 mg g–1 for Congo Red. The adsorption process is exothermic and follows pseudo-second-order kinetics.

The present review focuses on synergistic effectsof silica aerogels/xerogels on properties of polymer composites. In first part of the review, synthesis of silica aerogels/xerogels from inexpensive silica precursors in addition to silicon alkoxides is explained in detail. The promising properties such as highly porous structure, low density, high thermal stability, low thermal conductivity and acoustic velocity, and controllable hydrophobicity of silica aerogels/xerogels and their applications are enlarged upon. In other part of the review, enhanced properties of various polymer composites are summarized in the presence of silica aerogel/xerogel as filler. The significant improvements in thermal and sound insulation performance, physicomechanical properties and service life under harsh environmental conditions of polymer composites including silica aerogel/xerogel are represented. The desirable properties of the polymer composites extend potential high technology applications of these materials. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

This article is devoted to the study of the solvability of a periodic boundary-value problem for a third-order pseudoparabolic equation with a mixed derivative. Nonlocal problems for pseudo-parabolic equations have been investigated by many authors. Of particular interest in the study of these problems is caused in connection with their applied values. Such problems include highly porous media with a complex topology, and first of all, soil and ground. To solve this problem, new functions are introduced and the boundary-value problem for a third-order pseudoparabolic equation is reduced to a periodic boundary-value problem for a system of hyperbolic equations with a second-order mixed derivative. Based on the equivalence of the boundary-value problem for a system of hyperbolic equations and the periodic boundary-value problem for a family of systems of ordinary differential equations, two-parameter families of algorithms for finding an approximate solution are constructed and the conditions for unambiguous solvability of the problem under study are established.

The nanoplatforms based on upconversion nanoparticles (UCNPs) have shown great promise in amplified photodynamic therapy (PDT) triggered by near-infrared (NIR) light. However, their practical in vivo applications are hindered by the overheating effect of 980 nm excitation and low utilization of upconversion luminescence (UCL) by photosensitizers. To solve these defects, core-satellite metal-organic framework@UCNP superstructures, composed of a single metal-organic framework (MOF) NP as the core and Nd3+-sensitized UCNPs as the satellites, are designed and synthesized via a facile electrostatic self-assembly strategy. The superstructures realize a high co-loading capacity of chlorin e6 (Ce6) and rose bengal (RB) benefitted from the highly porous nature of MOF NPs, showing a strong spectral overlap between maximum absorption of photosensitizers and emission of UCNPs. The in vitro and in vivo experiments demonstrate that the dual-photosensitizer superstructures have trimodal (magnetic resonance (MR)/UCL/fluorescence (FL)) imaging functions and excellent antitumor effectiveness of PDT at 808 nm NIR light excitation, avoiding the laser irradiation-induced overheating issue. This study provides new insights for the development of highly efficient PDT nanodrugs toward precision theranostics.