Composite Counterpart Research Articles

Unveiling the potential of NiO–ZnCo2O4 nano-composites: Electrical, optical, electrochemical and antibacterial investigation

Zinc Cobaltite (ZCO) and Nickel Oxide (NiO) nanoparticles (NPs) were synthesized using a sol-gel technique, and their composites with different weight ratios were prepared using a straightforward sonication method. The NiO and ZCO NPs had small crystallite size of 10 nm and 18 nm, respectively. According to the ultraviolet–visible (UV–Vis) spectra, pure NiO and ZCO NPs exhibited band gaps of ∼3.5 eV and 3.3 eV. Antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacterial strains was also tested for the composite counterpart and its equivalents. Compared to pure NPs, the composite of 30 % ZCO-NiO (NZ3) had higher antibacterial activity with zone of inhibition of ∼13 mm against E. coli. The electrical and electrochemical properties were also explored and it was found that the composite of 50 % ZCO-NiO (NZ5) shows high specific capacitance of 188 F/g.

Fatigue performance of ECC link slab incorporated full RC girder joint-free bridges

The use of link slab (LS) made of Engineered Cementitious Composite (ECC) in the construction of joint-free bridge deck can meet structural performance requirements and enhance durability to minimize life cycle costs. Studies documented in the literature to date have been limited to composite steel-concrete I-deck girder bridges despite their commonly used reinforced concrete (RC) girder counterparts in construction. This paper deals with two span full RC deck girder joint-free bridges with ECC link slab (ECC-LS) constructed and tested under static and fatigue loading up to 1,000,000 cycles at 4 Hz subjected to mean stress level of 40% of girder ultimate load, followed by post-fatigue static loading to failure. Residual load, deflection, moment, rotation, stiffness, and energy absorbing capacity of fatigued bridge specimens are compared with its virgin (non-fatigued) counterparts to assess structural performance. Experimental moment capacities are compared with those obtained from existing analytical equations. The comparative performance of joint-fee bridge with RC deck girder is compared with its composite steel-concrete I-girder counterpart to assess its feasibility of construction.

Effects of Calcium and pH on Rheological Thermal Resistance of Composite Xanthan Gum and High-Methoxyl Apple Pectin Matrices Featuring Dysphagia-Friendly Consistency.

High-methoxyl apple pectin (AP) derived from apple was employed as the main ingredient facilitating rheological modification features in developing dysphagia-friendly fluidized alimentary matrices. Xanthan gum (XG) was also included as a composite counterpart to modify the viscoelastic properties of the thickened system under different thermal processes. The results indicate that AP is extremely sensitive to thermal processing, and the viscosity is greatly depleted under a neutral pH level. Moreover, the inclusion of calcium ions echoed the modification effect on the rheological properties of AP, and both the elastic property and viscosity value were promoted after thermal processing. The modification effect of viscoelastic properties (G' and G″) was observed whne XG was incorporated into the composite formula. Increasing the XG ratio from 7:3 to 6:4 (AP:XG) triggers the rheological transformation from a liquid-like form to a solid-like state, and the viscosity value shows that the AP-XG composite system exhibits better thermal stability after thermal processing. The ambient modifiers of pH (pH < 4) and calcium chloride concentration (7.5%) with an optimal AP-XG ratio of 7:3 led to weak-gel-like behavior (G″ < G'), helping to maintain the texture properties of dysphagia-friendly features similar to those prior to the thermal processing.

Piezoelectric polarization and interfacial electric field synergistically promote piezo-photocatalysis of in-situ transformed heterojunction

Photocatalysis is a promising approach for purifying water pollutants resources, but is greatly restricted by rapid photogenerated charges recombination. Herein, Bi2O2(OH)NO3-Bi2MoO6 heterojunction photocatalysts with strong interfacial electric field are synthesized via in situ transformation method with using Bi2O2(OH)NO3 as a self-sacrificial template. The intimate interface interaction renders a large interfacial potential, which allows efficient charge separation within the heterojunction. Thus, the photocatalytic activity was well optimized compared with the pristine catalyst and composite counterpart prepared by in situ growth route. Then, the piezoelectric polarization induced by ultrasonic vibration is introduced in the photocatalytic system, which yields a piezocatalytic activity and enhancement on the separation and transfer of photogenerated charge carriers. Benefiting from the piezoelectric polarization and interfacial electric field, the in situ transformed Bi2O2(OH)NO3-Bi2MoO6 heterojunction exhibits a prominent piezo-photocatalytic performance for degradation of tetracycline, much higher than that under sole light or ultrasound irradiation source as well as the individual catalyst. This work reveals the potential of the collaboration of piezoelectric polarization and interfacial electric field in photocatalysis.

Preparation of Ti3Si0.8Al0.2C2 Bonded Diamond Composites and Their Friction Properties Coupled with Different Counterfaces

Polycrystalline diamonds were sintered with the binder of Ti3Si0.8Al0.2C2 to solve the shortcomings of conventional metal binders and ceramic binders. Ti3Si0.8Al0.2C2 bonded polycrystalline diamond composites have been synthesized from a mixture of Ti3Si0.8Al0.2C2 powder (40 wt%) and diamond powder under 4.5–5.5 GPa at 1050–1300°C by high press and high-temperature technology. The characteristic peaks of TiC were observed at 4.5 GPa and above 1100°C. From the microstructure analysis, the diamond particles are equally dispersed throughout the Ti3Si0.8Al0.2C2 matrix and firmly bound to the matrix. The effects of the sintering conditions, test parameters, and counterparts on the friction properties of diamond composites were systematically analyzed. The friction coefficient between diamond composite and glass counterpart is between 0.18 and 0.33 and increases significantly at the speed of 400 rpm/min. SEM and EDS analysis show Ti3Si0.8Al0.2C2 has a strong holding force on the diamond particles. The wear mechanism is mainly abrasive, and there are obvious grooves on the surface of the glass ball. The friction coefficient of diamond composite sintered at 1050°C with POM decreases monotonically with increasing load and reaches the minimum value of 0.42 at 12 N. The higher sintering temperature (1150°C) resulted in lower friction coefficient for diamond/POM pairs. The friction coefficient of diamond/PP pairs decreases first and then increases with increasing load, reaching a minimum value of 0.431 at 10 N. The wear mechanism of PP and POM is a combination of abrasive wear and adhesive wear, while the abrasive chips of POM are small salt-like particles and the abrasive chips of PP are long flocs. The wear track of PP balls has a smoother surface than that of POM balls. For an Al pair, the friction coefficient of diamond composite sintered at 1150°C is higher than that of the composite sintered at 1050°C except for the 10 N load. The friction coefficient of the diamond composites with Cu pairs varies slightly with increasing load, with values ranging from 0.443 to 0.518 and decreases with increasing speed, reaching a minimum value of 0.396 at 600 rpm/min. The wear mechanism of Cu and Al is mainly based on adhesive wear. The presence of the diamond second phase improves the stability of Ti3Si0.8Al0.2C2 compared to the high-pressure treatment of single phase Ti3SiC2. The analysis of friction properties indicates that Ti3Si0.8Al0.2C2 bonded diamond composites are promising candidates for superhard tool materials.

Infill strategies for 3D-printed CF-PEEK/HA-PEEK honeycomb core-shell composite structures

Core-shell composite structures with a carbon fibers reinforced polyetheretherketone (CF-PEEK) honeycomb core and a hydroxyapatite reinforced polyetheretherketone (HA-PEEK) solid shell were printed by a multi-material fused filament fabrication process. The effects of deposition paths on the mechanical properties of the specimens were investigated. Manufacturing defects were characterized by an optical microscope and a micro-X-ray imaging system, and the defect formation process was detected by a high-speed camera. In-plane and out-of-plane compression experiments were conducted to analyze the compression behaviors of the specimens. It was found that the specimens printed by crossing paths had inferior compression strength because of the formation of manufacturing defects at the joints of two deposition lines. By using non-crossing printing paths, the out-of-plane compression strengths of the square honeycomb core specimen and its composite structure counterpart were improved by 12.5 % and 8.3 %, respectively, whereas those of the triangular honeycomb core specimen and its composite structure counterpart were enhanced by 17.0 % and 18.4 %, respectively.

Comparative strength and stability analysis of conventional and lighter composite flexible risers in ultra-deep water subsea environment

The hybrid flexible risers have a multi-layered structure and use thermoplastic composite for the pressure and tensile armour. In contrast, a conventional flexible riser uses heavier carbon steel as armour which significantly contributes to its weight. For shallow-water applications, the conventional risers are widely used in offshore oil and gas industry due to their corrosion resistance properties and low transportation costs. However, the weight of conventional risers is a key limitation in ultra-deep-water applications. This shortcoming can be addressed by including a lightweight carbon fibre reinforced polymer (CFRP) composite as one of the individual layers. The use of CFRP reduces the effective tension at the hang off point which is a key limitation in extending the range of flexible risers. Here, the dynamic stability and functional load interactions of both risers (viz: a thermoplastic CFRP riser and a conventional flexible riser) at a water depth of 3000 m were studied. A global analysis was performed considering the onerous 1000-year hurricane wave with 100-year currents. The investigation considered ±150 m vessel offsets, three vessel headings (viz: 135, 180, 225°) and three vessel draughts (ballasted, empty, loaded). Additionally, a numerical model with a variable bending stiffness was used to capture the orthotropic material behaviour of a flexible riser. Results showed that the buoyancy requirement and effective tension were 2.1 times greater and 2% higher for the conventional riser compared to its composite counterpart. The most onerous case for a conventional riser was at zero offset whereas for its composite counterpart was at –150 m along the length of a riser. It was observed that the heavier masses of a conventional riser aid in aligning the weight vector with the upward direction of the buoyancy force. Contrarily, the composite risers undergo large displacements leading to misalignments and instability. Furthermore, the observed bending radius of the flexible riser was found to be within the allowable minimum bend radius at the hog bend location.

BN-PVDF/rGO-PVDF Laminate Nanocomposites for Energy Storage Applications.

The increasing demand for high energy storage devices calls for concurrently enhanced dielectric constants and reduced dielectric losses of polymer dielectrics. In this work, we rationally design dielectric composites comprising aligned 2D nanofillers of reduced graphene oxide (rGO) and boron nitride nanosheets (BNNS) in a polyvinylidene fluoride (PVDF) matrix through a novel press-and-fold technique. Both nanofillers play different yet complementary roles: while rGO is designed to enhance the dielectric constant through charge accumulation at the interfaces with polymer, BNNS suppress the dielectric loss by preventing the mobility of free electrons. The microlaminate containing eight layers each of rGO/PVDF and BNNS/PVDF films exhibits remarkable dielectric performance with a dielectric constant of 147 and an ultralow dielectric loss of 0.075, due to the synergistic effect arising from the alternatingly electrically conductive and insulating films. Consequently, a maximum energy density of 3.5 J/cm3-about 18 times the bilayer composite counterpart-is realized. The high thermal conductivities of both nanofillers and their alignment endow the microlaminate with an excellent in-plane thermal conductivity of 6.53 Wm-1K-1, potentially useful for multifunctional applications. This work offers a simple but effective approach to fabricating a composite for high dielectric energy storage using two different 2D nanofillers.

Improving glass‐fiber epoxy composites via interlayer toughening with polyacrylonitrile/multiwalled carbon nanotubes electrospun fibers

AbstractThe development of innovative engineered epoxy composites aiming to manufacture cost‐efficient materials with reduced weight and enhanced physical properties remains as a current industrial challenge. In this work we report an original procedure for manufacturing glass‐fiber epoxy reinforced nanocomposites (GFECs) by employing electrospun fiber‐mats as a reinforcing phase. These fibers have been produced from polyacrylonitrile and multiwalled carbon nanotubes solutions. Optimal protocols are designed by combining Taguchi method with the morphological, structural and mechanical properties obtained by scanning electron microscopy, profilometry and tensile tests. It is demonstrated that GFECs fabricated using GF800 glass fiber show an improvement/enhancement of the mechanical properties with a fracture strain up to 500 MPa (around 20% higher than the non‐reinforced epoxy composite counterpart). It is also shown that GFECs fabricated using GF3M glass fiber exhibited a reduction of the roughness up to 56%, which corresponds with a roughness improvement from N8 to N7 following the guidelines provided by the ISO 1302. These results suggest that this type of nanocomposites would be suitable to be used in the aeronautics and automotive industries.

Novel segregated-structure phase change materials with binary fillers and the application effect in battery thermal management

The heat cannot be effectively dissipated of lithium-ion battery during the long-term charge and discharge cycles process, which will lead to battery overheating to aging and even thermal run away. The battery thermal management system (BTMS) based on phase change materials is a passive cooling method, which can achieve the effect of cooling and heat dissipation without consuming energy. In this paper, a novel segregated-structure composite phase change material (PA-CNTs@BNX) compose of carbon nanotube (CNTs) reinforced paraffin as “core” and modified hexagonal boron nitride (BN-OH) as “shell” through electrostatic force is proposed. And PA-CNTs@BNX with segregated-structure is constructed by hot-pressing method, which can further enhance its thermal conductivity in comparison to the composite counterpart with random filler distribution. In addition, the heat conduction paths in the micro-region are established by the addition of CNTs. PA-CNTs@BN30 possesses highest thermal conductivity among PA-CNTs@BNX, whose values is enhanced 176 % compared with pure PA. Meanwhile, PA-CNTs@BN30 have high reserved latent heat and could maintain its thermal reliability, which promoting its applications in BTMS. Novel segregated-structure PA-CNTs@BNX with binary fillers is successfully prepared by simple method, and it has important industrial significance in BTMS.

Multi‐walled carbon nanotube grafted 3D spacer multi‐scale composites for electromagnetic interference shielding

AbstractThe development of structural fiber reinforced polymer composites with various additional functionalities is becoming a hot research area to achieve the application of multi‐functional composites in the aerospace and automotive industries. An innovative material solution is 3D spacer composites with distinctive anisotropic structural characteristics. Herein, we report the manufacturing of multi‐walled carbon nanotubes (MWCNTs) grafted of 3D spacer glass/epoxy multi‐scale composites and their electromagnetic interference shielding efficiencies (EMSE). To manufacture multi‐scale composites, we utilized dip coating, vacuum filtering, and vacuum infusion methods to introduce MWCNTs of the woven fabric, while we also modified the epoxy resin with MWCNTs to increase electrical conductivity of intrinsic insulator epoxy resin. Owing to the rectangular‐shaped channel structure, which is beneficial for multiple reflection and scattering between top and bottom face sheets, the resultant 3D spacer multi‐scale composite represented a good EMSE performance of −18.3 dB in the frequency range of 8.2–12.4 GHz with an increase of 107% comparing the corresponding neat composite counterpart. Moreover, we measured the in‐plane conductivity as 1.89E‐2 S/m after MWCNTs grafting, while the out‐of‐plane conductivity remained three times lower than the in‐plane conductivity. Dynamic mechanical analysis revealed that the storage modulus increased almost three times with the MWCNTs grafting, while glass transition temperature shifted to higher temperatures (from 77.5 to 89.7°C). Therefore, we anticipate that our study will expand the use of 3D spacer composites in the aviation and automotive industries.

Influence of Natural Serpentine on Tribological Performance of Phosphate Bonded Solid Coatings

Natural serpentine powders as functional fillers were incorporated to promote the anti-wear performance of phosphate-bonded solid coatings. Optimal mass percent of natural serpentine in phosphate coatings was first explored. Thereafter, to further stimulate strengthening effect of natural serpentine on tribological performance of phosphate composite coatings, harsher friction condition on the phosphate composite coatings was conducted. The experimental result indicated that the optimal incorporation of natural serpentine in phosphate coatings was 10 wt.%, through which anti-wear performance of phosphate coatings was significantly elevated. Additionally, accompanied by the increase of applied load and sliding speed, natural serpentine was gradually activated, and interfacial interactions between naturals serpentine and counterface were intensified. As a result, a continuous protective tribo-film was in situ formed on the counterface, through which serious furrows generated on the counterface were effectively self-repaired during the friction process. What’s more, further abrasion on both phosphate composite coatings and counterface was also greatly restrained. Natural serpentine as the enhanced phase was incorporated into phosphate bonded solid coatings. The experimental results indicated that when applied load and sliding speed were increased, transfer and adhesion of phosphate composite coatings on the counterface were apparently intensified, and simultaneously, serious furrows generated on the wear spot were obviously reduced. What’s more, a continuous tribo-film was in-situ formed on the counterface, through which the direct abrasion between phosphate composite coatings and counterpart steel ball was restrained, and therefore, the anti-wear performance of phosphate composite coatings was significantly promoted.

Residual Stress Distribution and Microstructure Characterization of Particle Reinforced Titanium Matrix Composite After Shot Peening Treatment: A Review

Shot peening (SP) can modify the surface properties of titanium alloys and titanium matrix composites (TMCs). Based on our previous work in the last ten years, the microstructure and mechanical properties of SP treated Ti-6Al-4V (TC4) and (TiB+TiC)/TC4 are summarized in this review. The compressive residual stress (CRS) was formed on the surface after SP. At different SP intensities, the thickness of the surface CRS layer was improved with increasing SP intensities. During the stress peening, the CRS increased evidently, and the increment was proportional to the prestress. Besides, CRS’s thermal relaxation was investigated, which showed that the CRS in the whole deformation layer was relaxed. The relaxation mechanism could be explained by the Zener-Wert- Avrami model. The microstrain, the domain size, and the dislocation density of the peened layer were investigated using the Voigt method. The domain size of TC4 was smaller than the composite, and the microstrain of the TC4 was higher than the composite. The average dislocation density was increased after SP due to the existence of reinforcements. Utilizing the Rietveld method to analyze the microstructure after SP, the variations were similar to the Voigt method’s results. Also, the composite’s stability was higher than TC4 because of the existence of reinforcements. Hardness analysis revealed that the existence of reinforcements raised the hardness. In the peened layer, the surface’s hardness was maximum, and it decreased with the increase in depth. At the same temperature, the hardness of the TC4 was smaller than the composite counterpart. Finally, the strengthening mechanism of SP was discussed and summarized based on the above analysis.

Thermo-conductive phase change materials with binary fillers of core-shell-like distribution

Phase change materials (PCMs), in light of high latent heat and isothermal performances during phase transition, behave huge potential in thermal management, and energy storage/conversion, yet still severely suffered from intrinsic unsatisfied thermal conductivity and inferior shape stability. Regarding to these bottlenecks, different from traditional complicated and energy-consuming methods, a facile strategy through merely physical mixing procedures was proposed for fabrication of PCMs with core-shell-like distribution of binary fillers composed of “core” containing polyethylene glycol (PEG) nanocomposites with graphene nanoplates (GNPs) and “shell” filled with hexagonal boron nitride (h-BN). Therefore, as-prepared composite achieves a thermal conductivity of 3.63 W·m−1 K−1 at GNPs/h-BN loading of 0.625 vol% and 15 vol%, respectively, almost 1.5-fold of that of composite counterpart with random filler distribution. Meanwhile, it also possesses high reserved latent heat and could maintain its original shape even at 90 °C, largely promoting its widespread applications.

Wear behavior of alkaline pulsed electrodeposited nickel composite coatings reinforced by ZnO nanoparticles

Nickel-ZnO nanocomposite coatings were fabricated by pulse electrodeposition in an alkaline bath. The effect of different deposition parameters such as current density, duty cycle, and pulse frequency as well as the impact of addition of 10 g/l ZnO nanoparticles into the nickel matrix on the friction behavior of fabricated coatings were investigated. X-ray diffraction, atomic force microscopy, scanning electron microscopy, microhardness test, and pin-on-disk wear test were utilized to assess the coatings characteristics, mechanical behavior, and wear resistance and a thorough comparison was performed between the pure nickel coating and its reinforced composite counterpart, with respect to their surface morphology, surface topography, and wear resistance properties. Our results indicate that by ZnO incorporation into the coating, the number of nucleation sites for nickel crystals increases, the crystal growth is retarded, and a nanocomposite coating with smaller grains can be fabricated. The incorporation of ZnO led to significantly increase in microhardness, changed the wear mechanism from adhesion to abrasion, and improved the wear rate. By increasing the electrodeposition current density (from 4 to 10 A/dm2), the wear rate was noticeably decreased while the friction coefficient was significantly enhanced. As the electrodeposition duty cycle and pulse frequency were increased to 75% and 100 Hz, respectively, wear rate of the composite coating increased noticeably as a consequence of the changes in the coating properties. The optimum electrodeposition condition for Ni–ZnO nanocomposite coatings was achieved at 10 A/dm2, γ = 50% and f = 10 Hz resulting in a coating with the lowest wear rate (3.2539 × 10−4 mm3/Nm), minimum weight loss (0.0014 gr), highest microhardness (290 Hv), maximum ZnO incorporation rate (4.04 vol% ZnO), and highest friction coefficient (0.972) among all investigated coatings. It was concluded that increasing current density improved the wear resistance while the enhancement of duty cycle and pulse frequency led to worsen it.

Tuning electroluminescence performance in Pr-doped piezoelectric bulk ceramics and composites

Alternating current electroluminescence (ACEL) shows great potential in lighting, display and intelligent skin. Herein, the ACEL properties of Pr3+-doped Ba0·85Ca0·15Ti0·90Zr0·10O3 ceramic and its PDMS-based composite have been investigated. Intense red EL emission was obtained in the ceramic sample whereas blue EL emission of Pr3+ was observed for the first time in the composite counterpart. The red EL emission should be attributed to the impact of hot electrons driven by the large piezoelectric electric field. Owing to the cross-relaxations through the 4f5d levels and Pr-to-metal charge transfer state, the 3PJ emissions were completely quenched, and thus leading to an enhancement in red emission. However, external E field induced a large local piezoelectric deformation of the ceramic particles embedded in the PDMS matrix, which in turn caused a bending of CB and then a downwards shift of the 4f5d levels from the CB. Hence the cross-relaxations were hindered, and the blue EL emission was observed in the composites. The results would attract attention of functional materials studies and expand our understanding of such facile structure and oxide EL devices to facilitate their use in integral part of flexible device systems.

On lateral crashworthiness of aluminum/composite hybrid structures

To improve the lightweight and crashworthiness in vehicular engineering, there has been growing interests in metal/composite hybrid configuration, which is relatively newer than traditional metallic or composite structures. It is of vital importance to understand lateral crushing behaviors of hybrid system to gain maximum benefits from the structural configuration. In this present study, quasi-static lateral compression tests were carried out experimentally to investigate the transverse failure modes and crashworthiness characteristics of four different circular hybrid tubes made of either aluminum/carbon fiber reinforced plastics (CFRP) or aluminum/glass fiber reinforced plastics (GFRP) materials. From the experiments, it is found that the load carrying capacity of the aluminum/composite hybrid tubes with an inner composite tube was substantially higher than that of hybrid tubes with an outer composite counterpart. This is due to the fact that more significant delamination was initiated and propagated around the inner composite tube under transverse loading, which improved its lateral crushing characteristics. The interactive effects between single aluminum tube and single composite (CFRP or GFRP) tube was also investigated; and it is found that the specific energy absorption (SEA) of hybrid tube AL-T2-CF-P8 (2.41 J/g) and AL-T2-GF-P8 (2.27 J/g) were 58% and 47% higher than the sum of single aluminum tube and single composite tube alone, respectively. Based upon the experimental results, the finite element (FE) models were developed and validated to further explore the effects of hybrid ratios (i.e. aluminum vs. CFRP/GFRP of 4:0, 3:1, 2:2, 1:3 and 0:4) and stacking sequence on lateral crashworthiness. It is found that the aluminum thickness of a higher-ratio configuration can largely improve the load carrying and energy absorption capacities under lateral compression. For the six different stacking sequences considered here, the hybrid tubes with a symmetrical configurations [CF-P4-AL-T1]s and [GF-P4-AL-T1]s are of the best crashworthiness performance with the highest SEA of 3.43 J/g and 3.29 J/g, respectively. This study provides thorough understanding of the aluminum/composite hybrid tube subject to transverse crushing load, and would be of considerable implication to vehicular applications.

Tough macroporous phenolic resin/bacterial cellulose composite with double-network structure fabricated by ambient pressure drying

In this work, a large size of macroporous phenolic resin (PR)/bacterial cellulose (BC) composite with double-network structure was fabricated simply by soaking, heating, solvent exchange, and ambient pressure drying. The mechanism and influence factors for the fabrication of this macroporous composite were systematically elaborated. One network of macroporous composite was composed of PR beads, and the other derived from original BC nanofibers. They supported and reinforced each other, avoiding the collapse of interconnected porous structure and achieving low density (0.29 g/cm3), high porosity (77.7%), low thermal conductivity (0.10 W/m K), and excellent compressive strength (7.97 ± 2.24 MPa). Through further carbonization, carbon counterpart that maintained fine structure and good performance can also be obtained. The surface of macroporous composite was extremely hydrophilic. On the contrary, its carbon counterpart possessed a highly hydrophobic surface (contact angle = 118.2°). These properties suggest that the macroporous composite and carbon counterpart may have potential applications for filtration, separation, and thermal insulation materials. Moreover, this work will provide a novel perspective for the fabrication of porous composites with BC as the template and 3D nanofiber reinforcement simultaneously.

Bend-free design of ellipsoids of revolution using variable stiffness composites

Shells are commonly used in many structural applications due to their high specific load carrying capabilities. One of the most interesting features of shell structures is that they can resist external transverse loads by developing membrane stresses in the small deformation regime yet, in general, also generate inefficient bending deformations and stresses. In this study, a composite ellipsoid shell of revolution, under internal pressure, is designed for zero bending and curvature change. To this end, the stiffness properties of elliptical composite shell structures are tailored by fibre steering. A new definition for a bend-free state, independent of internal pressure, is presented. Based on this definition, the internal pressure-induced bending state of an isotropic ellipsoidal shell of revolution is compared with its tailored composite counterpart. Results show that up to a specific level of ellipticity, a bend-free state is achievable by fibre steering in elliptical composite shells of revolution. Finally, a failure study is performed to assess the potential improvement of the maximum allowable internal pressure by bend-free design.

Co-complex protein membership evaluation using Maximum Entropy on GO ontology and InterPro annotation.

MotivationProtein–protein interactions (PPI) play a crucial role in our understanding of protein function and biological processes. The standardization and recording of experimental findings is increasingly stored in ontologies, with the Gene Ontology (GO) being one of the most successful projects. Several PPI evaluation algorithms have been based on the application of probabilistic frameworks or machine learning algorithms to GO properties. Here, we introduce a new training set design and machine learning based approach that combines dependent heterogeneous protein annotations from the entire ontology to evaluate putative co-complex protein interactions determined by empirical studies.ResultsPPI annotations are built combinatorically using corresponding GO terms and InterPro annotation. We use a S.cerevisiae high-confidence complex dataset as a positive training set. A series of classifiers based on Maximum Entropy and support vector machines (SVMs), each with a composite counterpart algorithm, are trained on a series of training sets. These achieve a high performance area under the ROC curve of ≤0.97, outperforming go2ppi—a previously established prediction tool for protein-protein interactions (PPI) based on Gene Ontology (GO) annotations.Availability and implementation https://github.com/ima23/maxent-ppi Supplementary information Supplementary data are available at Bioinformatics online.