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Cryphalus piceae parasitizes various economically important conifers. Similar to other bark beetles, C. picea vectors an assortment of fungi and nematodes. Previously, several ophiostomatoid fungi were isolated from C. piceae in Poland and Japan. In the present study, we explored the diversity of ophiostomatoid fungi associated with C. piceae infesting pines in the Shandong Province of China. We isolated ophiostomatoid fungi from both galleries and beetles collected from our study sites. These fungal isolates were identified using both molecular and morphological data. Through this study, we recovered 176 isolates of ophiostomatoid fungi representing at least seven species. Ophiostoma ips was the most frequently isolated species. Analyses of molecular and morphological data indicated four of the ophiostomatoid fungal species recovered in this study were previously undescribed. Hereby, we described these species as Ceratocystiopsis yantaiensis sp. nov., C. weihaiensis sp. nov., Graphilbum translucens sp. nov. and Sporothrix villosa sp. nov. A majority of the ophiostomatoid fungi recovered in this study were novel species. This suggests that the forests in China harbour an assortment of undescribed ophiostomatoid fungi yet to be discovered.

Cryphalus piceae attacks various economically important conifers. Similar to other bark beetles, Cr. piceae plays a role as a vector for an assortment of fungi and nematodes. Previously, several ophiostomatoid fungi were isolated from Cr. piceae in Poland and Japan. In the present study, we explored the diversity of ophiostomatoid fungi associated with Cr. piceae infesting pines in the Shandong Province of China. We isolated ophiostomatoid fungi from both galleries and beetles collected from our study sites. These fungal isolates were identified using both molecular and morphological data. In this study, we recovered 175 isolates of ophiostomatoid fungi representing seven species. Ophiostoma ips was the most frequently isolated species. Molecular and morphological data indicated that five ophiostomatoid fungal species recovered were previously undescribed. Thus, we proposed these five novel species as Ceratocystiopsis yantaiensis, C. weihaiensis, Graphilbum translucens, Gr. niveum, and Sporothrix villosa. These new ophiostomatoid fungi add to the increasing number of fungi known from China, and this evidence suggests that numerous novel taxa are awaiting discovery in other forests of China.

This study investigated the sublimation of Mn and microstructural evolution of binary Fe/Mn compacts sintered at various temperatures in a vacuum. A high sintering temperature or a lengthy holding time promotes powder densification. Due to sublimation of Mn, the weight loss of the compacts mainly occurs during the isothermal holding stage of the sintering process; it increases significantly from 1.5 wt.% for sintering at 1000 °C to 8.6 wt.% at 1200 °C. For the first time, the phase evolution in the binary elemental compacts was clarified using in situ neutron diffraction. The γ-austenite phase emerges during temperature ramping to 536 °C, while β-Mn and α-Fe disappear at 774 °C and 881 °C. The neutron diffraction also revealed that single phase γ-austenite forms in the Fe-Mn compacts if the temperature is ≥ 881 °C.

This work investigated the effects of current density and deposition time on the properties of electrodeposited PbO2. The PbO2 preparation was conducted on Ti/SnO2–Sb substrates by galvanostatic anodic deposition in a newly proposed methanesulfonate electrolytic solution. Phase constituents and microstructures of the deposited PbO2 coatings were characterized. Increasing current density in the range ≤ 100 mA cm− 2 leads to the formation of highly textured coatings with an increased content of α-PbO2 phase. Concurrently, a high current density favors a compact and flat surface morphology. The study of deposition time indicates a change of crystallite growth manner from an initially random growth to a later-stage preferred growth along distinct orientations. The change of crystallite growth is corroborated by the cross-sectional microstructures of the PbO2 deposits. The microstructural transition occurs only in the initial deposition stage. After a brief period, prolonged electrodeposition barely changes the surface morphology of PbO2 coatings.

A novel flexible nickel–cobalt layered double hydroxide/polyaniline/bacterial cellulose (NiCo-LDH/PANI/BC) electrode with both excellent electrochemical and mechanical performances is obtained through successively coating PANI and NiCo-LDH on BC. In addition to making the 3D open network (BC) conductive, the PANI layer also functions as a “nanoglue” to uniformly and robustly immobilize nanostructured NiCo-LDH onto the highly enlarged surface of PANI/BC nanofibers owing to its rough surface and hydrophilicity. Benefitting from the hierarchical structure with a 3D conductive network, unobstructed channels, numerous electroactive sites and induced synergistic effect, the NiCo-LDH/PANI/BC electrode shows excellent electrochemical performance in an aqueous electrolyte, exhibiting a high specific capacitance of 1690 F g−1 (761 C g−1) at 1 A g−1, enhanced rate capability (778 F g−1 or 350 C g−1 at 15 A g−1) and outstanding cycling stability (83.2% capacitance retention after 5000 cycles). Besides, the NiCo-LDH/PANI/BC also shows excellent foldability, high tensile strength (90.8 ± 4.9 MPa), high elongation at break (7.2 ± 0.7%) and outstanding electrochemical stability during bending and stretching. Moreover, a flexible all-solid-state supercapacitor is assembled with NiCo-LDH/PANI/BC as the positive electrode and N-doped carbonized BC/carbon cloth as the negative electrode, delivering a high energy density of 47.3 W h kg−1 at a power density of 828.9 W kg−1, and superior cycling stability (91.4% capacitance retention after 3000 cycles). Therefore, this work provides a new path for high-performance flexible energy storage devices and offers a new vision for uniformly and robustly assembling nanohybrids.

Polyethylene glycol (PEG), with polymethyl methacrylate (PMMA) as the backbone binder component, is a common primary binder component in the design of water soluble binder systems for metal injection moulding (MIM). However, PEG crystallises upon cooling, producing voids in the injection moulded parts. These voids ultimately lead to porosity and degraded mechanical properties in the sintered bodies. We have previously reported on the use of polyvinylpyrrolidone (PVP) as a crystallisation inhibitor in the PEG/PMMA binder system to suppress void formation. In this paper, PEG/PMMA/PVP binder-based feedstocks were prepared with a 67 vol% solid loading in order to evaluate the effects of PVP incorporation on the PEG/PMMA binder for titanium MIM. The homogeneity and rheological behaviours of the feedstocks with varying amounts of PVP were compared with the base PEG/PMMA binder-based feedstock. Microstructural observation, impurity measurement and mechanical testing were carried out. It was found that incorporation of 20 wt% PVP into the PEG produced a void-free, high quality Ti-MIM component, with an average final density of 98% and a tensile elongation of 9.5%.

Free-standing and flexible activated flax fabrics (AFFs) with hierarchical meso/microporous structures have been prepared through a novel one-step synthetic strategy of rapid carbonization/activation of flax fabrics in CO2. The fast heating and the high partial pressure of CO2 inhibit the decomposition of flax fabrics during heating up, and thus keep more char materials for gasification at high temperature. It is found that such a process retains a considerable amount of oxygen groups and creates relatively large pores, bringing a one-step process to carbonize and activate flax fabrics at the same time and offering the freedom of tuning the mesopore volume/total pore volume (Vmeso/Vtotal) ratio. Notably, the Vmeso/Vtotal ratio is significantly increased from 27.6% to 67.0%. As a result, the flexible electrodes show excellent electrochemical performance in aqueous electrolyte, exhibiting a large specific capacitance (205 F g−1 or 140 F cm−3 at current density of 0.1 A g−1), a good rate capability (139 F g−1 or 95 F cm−3 at 35 A g−1), and an excellent cycling stability (∼96.6% retention after 3000 cycles). The excellent rate performance can be attributed to the improved ion transport (due to large pore size) and the good wettability (due to the oxygen group) of electrolyte.

In this work, the thermal behavior of graphene foam (GF) filled polymer composite is investigated using the finite element method. Owing to the interconnected structure of GF, which forms effective heat pathways, GF filled polymer composite is endowed with good thermal properties. The effect of contact thermal resistance, interfacial thermal conductance, as well as GF strut length and diameter on thermal conductivity is simulated and compared with experimental results. It is found that the contact thermal resistance is more important than interfacial thermal conductance in terms of thermal conductivity of composite. The contact thermal resistance between GF filled polymer composite and copper block is about 10 −4 to 10 −3 m 2 KW −1 . The shorter length and larger radius of GF struts are beneficial for heat dissipation. The results prove that the GF filled polymer composite is a good candidate material for heat management of electronic devices.

Graphene has attracted intense attention in electrochemical capacitors (ECs) as electrode material due to its excellent electronic, mechanical and thermal properties as well as its ultrahigh specific surface area. Considering the electrochemical performance of an EC is largely determined by electrode architectures, this review particularly focus on recent progress on designing and controlling the architectures of graphene based electrodes. After briefly introducing the energy storage mechanisms of ECs and the effects of pore sizes and pore size distribution on capacitance, we highlight the development and challenges for one to three dimensional graphene electrodes, their respective advantages, and corresponding electrochemical performance including specific capacitance, energy density, power density, rate capability and cyclic stability. This review also highlights the effects of introducing other electro-active materials such as carbon nanotubes, conducting polymers and metal oxides on the electrochemical performance of one to three dimensional graphene hybrid electrodes.

The effect of carbon fibre (CF) on the mechanical and thermal properties of graphene foam (GF)/polydimethylsiloxane (PDMS) composites was investigated. The CFs with different weight percentages (2, 4, 6, 8 and 10 wt%) were thoroughly dispersed in the PDMS matrix using a high-speed shearing and stirring method and then the GF was filled with the mixture. The CF/GF/PDMS composites were characterized in terms of microstructure, mechanical and thermal properties using various testing techniques. The results reveal that the addition of CF observably improved the mechanical and thermal properties of GF/PDMS composites. For 10 wt% CF/GF/PDMS composite, the tensile strength and Young's modulus are increased by 52% and 71% respectively compared with GF/PDMS composite. In addition, its thermal conductivity reaches 0.55 Wm −1 K −1 , i.e., an increase by about 41% and 162% compared to GF/PDMS composite and pure PDMS, respectively. SEM images show a strong interfacial bonding between CF and PDMS.

B, N dual-doped sisal-based activated carbon (BN-SAC) with a multiscale porous structure for high-rate supercapacitor electrode was prepared through a novel and facile strategy. With the inherent cellular channels serving as primary macropores, secondary mesopores and micropores are generated on the fiber surface and tracheid walls through low-pressure rapid carbonization of (NH4)2B4O7-containing sisal fibers and successive KOH activation. In addition to introducing B, N atoms into the BN-SAC, the additive also facilitates the formation of mesopores due to the rapid gas evaporation during its decomposition, leading to significantly increased specific surface area (2017 m2 g−1) and mesoporosity (68.6%). As a result, the BN-SAC-3 shows highly enhanced electrochemical performance including a high specific capacitance of 304 F g−1, excellent rate capability (with 72.6% retention at 60 A g−1) and superior cycling stability (4.6% capacitance loss after 3000 cycles). After assembling the BN-SAC-3 into symmetric supercapacitor, it shows a specific capacitance of 258 F g−1 at 1 A g−1 with 76.4% retention at 40 A g−1 in 6 M KOH electrolyte, and delivers a maximum energy density of 24.3 W h kg−1 at a power density of 612.8 W kg−1 in 1 M TEABF4/AN electrolyte. This work provides a new strategy for the synthesis of multiscale porous ACs for high-performance supercapacitors or other energy storage and conversion devices and is expected to be applied on other biomasses for large-scale production.

In this letter, the optical properties of InAs (QDs)/GaInAsP on InP substrate grown by gas source molecular beam epitaxy are investigated. By measuring and analyzing the photoluminescence spectra of InAs (QDs)/GaInAsP/InP at different temperatures and excitation powers, the origin of each emission is verified. And it is found that, with the temperature increasing, the emission intensity of GaInAsP wetting layers decreases firstly (T

3D Printing additive manufacturing is a rapidly developing form of technology. Currently able to manipulate many polymers (both synthetic and organic) this technique is quickly becoming an integral part of biotechnological developments. This paper highlights the fundamentals of this technology namely the mechanisms employed in standard 3D printing it then introduces tissue engineering a field in which current versions of this technology have been employed as bioprinting. The limitations with respect to tissue engineering are discussed outlining the current technologies inability to produce nanofibre based structures common in tissue such as tendon cartilage and cornea. From this requirement for nanofibre production electrospinning is introduced as a potential pathway for future tissue engineering 3D printing technologies and finally the current combination of this technology with 3D Printing is discussed yielding current limitations in retaining required nano-resolutions.

This paper reviews current research on the design, processing and finite element analysis (FEA) of bone implants for the human body. The feasibility of producing carbon fibre composite implants, in particular knee and hip replacements which are common bone replacements by 3D printing, is discussed. The relationship between design and material requirements is elaborated.

The nature of fibre placement/manipulation in electrospinning has been recorded through the utilization of surface actuation and electrostatic manipulation. This study investigates the potential of a simplistic approach to fibre placement manipulation through the utilization of non-uniform non-conducting collecting surfaces. A solution of Nylon 6,6 and Formic acid was electrospun with an ES1a device and through the use of SEM analysis submicron and nanofibre alignment was identified. This study achieved the generation of actuation-less and electrode-less alignment reiterating current literatures rationale of alignment formation. The study noted limitations regarding the potential combination of mold/cavity and electrospinning based manufacturing. From this work future recommendations regarding surface modification have been derived.

Two different sizes of polydopamine-coated layered double hydroxides (D-LDHs) are incorporated into polycaprolactone-based polyurethane (PU) to enhance the mechanical and shape memory properties of the PU. The results show that D-LDH interacts strongly with hard segments and hence enhancing phase separation between hard and soft segments. It is found that the tensile moduli of the PU/D-LDH nanocomposites are much higher than that of neat PU at 60 oC. In comparison with neat PU, the nanocomposite with 2 wt% of small D-LDH exhibits a 60% increase in recovery stress while shape fixity and strain recovery ratio are also improved simultaneously. This is because at low filler loading, most small D-LDH nanosheets interact with hard domains and they are not large enough to connect neighbor hard domains. They can hence reinforce the hard domains without sacrificing the elasticity of the system. Two-dimensional X-ray diffraction studies indicate that most small D-LDH nanosheets are able to rotate back from aligned state to original random state in shape recovery process, justifying the improved strain recovery ratio. ASTAR (Agency for Sci., Tech. and Research, S’pore) Accepted version

The spatial and temporal coherence of the fluorescence emission controlled by a quasi-two-dimensional hybrid photonic–plasmonic crystal structure covered with a thin fluorescent-molecular-doped dielectric film is investigated experimentally. A simple theoretical model to describe how a confined quasi-two-dimensional optical mode may induce coherent fluorescence emission is also presented. Concerning the spatial coherence, it is experimentally observed that the coherence area in the plane of the light source is in excess of 49 μm2, which results in enhanced directional fluorescence emission. Concerning temporal coherence, the obtained coherence time is 4 times longer than that of the normal fluorescence emission in vacuum. Moreover, a Young's double-slit interference experiment is performed to directly confirm the spatially coherent emission. This smoking gun proof of spatial coherence is reported here for the first time for the optical-mode-modified emission.

Carbon nanotube reinforced pyrolytic carbon/silicon nitride (CNT-PyC/Si 3 N 4 ) composite ceramics were fabricated through in-situ growth of CNTs in PyC–Si 3 N 4 ceramics by precursor infiltration and pyrolysis. CNTs were in-situ formed by the addition of nano-sized Ni into phenolic resin and Si 3 N 4 powder blend, and the content of CNTs increased with the increase of Ni content. Due to the formation of CNTs in the inter-particle pores of CNTs/PyC–Si 3 N 4 ceramic, the PyC wrapped Si 3 N 4 particles were bridged by CNTs, which led to the increase of electrical conductivity. Different from the previously reported PyC–Si 3 N 4 ceramics fabricated by chemical vapor infiltration (CVI), the PyC–Si 3 N 4 ceramics exhibited a shielding mechanism dominated by absorption. Compared to PyC–Si 3 N 4 ceramics prepared with same procedure, the shielding effectiveness of CNTs-PyC/Si 3 N 4 increased significantly with the formation of CNTs. With the increase of CNT content, the shielding effectiveness of CNTs/PyC–Si 3 N 4 ceram i cs increased from 25.5 to 43.6 dB, in which the absorption shielding effectiveness increased from 15 to 30 dB over the frequency range of 8.2–12.4 GHz.

Correction for ‘B, N-dual doped sisal-based multiscale porous carbon for high-rate supercapacitors’ by Heng Wu et al., RSC Adv., 2019, 9, 1476–1486.

Low-cost jute-based carbon fibers were fabricated by pre-oxidation and carbonization. The chemical, morphological and crystal structure of the jute fibers during pre-oxidation were investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, elemental analysis, X-ray diffraction and scanning electron microscopy. Results show that the optimum pre-oxidation temperature range is from 250 to 340 °C. At 250 °C, significant oxidation occurs, the amount of C O functional groups reaches a maximum, the typical cellulose crystal structure disappears and a new aromatic structure appears. The C O functional groups are gradually lost while an aromatic structure steadily develops with a further increase of temperature from 250 to 340 °C. The tensile strength of the jute-based carbon fibers increases with increasing amount of the aromatic structure during pre-oxidation, rather than that of C O groups. The highest tensile strength of the carbon fibers is 200.4 ± 41.0 MPa. [New Carbon Materials 2013, 28(6): 448–453]

The mechanical properties and the life cycle assessment (LCA) of jute woven fabric composites and their hybrids are investigated. Jute woven fabric composites were sandwiched with glass woven composites with the epoxy matrix. The sandwiched composites were prepared using the resin infusion under flexible tooling method. The water absorption test was performed on jute woven composites and composite sandwiches. It shows that thin layers of glass woven composites in the composites sandwich decelerate water penetration to jute woven composites, which are the core materials. The water absorption process applied to jute woven composites and their sandwich was modeled using Fick’s second law. The glass woven composites at the outer surface of the sandwich can act as strong skins. The bending and impact (drop weight) properties of jute–glass woven composites are higher than those of jute woven composites. A commercial LCA software product was employed to evaluate the environmental impacts of manufacturing the jute woven composites and their hybrids. The manufacturing of jute–glass woven composites had more negative environmental impacts (global warming, ozone depletion, etc.) than that of jute fabric composites, because glass fibres are less environmental friendly than natural fibres.

Owing to the widespread presence of electromagnetic interferences, it is necessary to develop new materials with excellent high-temperature electromagnetic wave (EM) absorption properties. In the present work, ZnO is infiltrated into porous ZrSiO4 substrates to form ZnO/ZrSiO4 composite ceramics using sol-gel process. The doping of aluminum results in the improvement of electrical conductivity and the significant change in the morphology of ZnO. With the increase in environment temperature during measurement, the permittivity of the composite ceramics increases first and then decreases dramatically, which is attributed to the change in conductive loss. The electrical conductivity increases with increasing measurement temperature. However, the concentration of oxygen vacancies decreases under air atmosphere when the measurement temperature increases continuously, which results in the reduction in conductivity. Therefore, permittivities of the undoped and doped ceramics measured at 673 K are higher than the ones at the other temperatures. The composite ceramics maintain a relatively high EM absorption coefficient, low reflection coefficient (RC), and wide effective absorption bandwidth at environment temperatures up to 773 K. As a result, we conclude that the ZnO/ZrSiO4 composite ceramics exhibit a promising prospect as a kind of high-temperature EM absorbing material.

A (1→6)-β-D-glucan (WPLE-N-1) and two mannogalactoglucans (WPLE-N-2 and WPLE-N-3) were isolated from the basidiocarps of Lentinus edodes by hot water extraction, ethanol precipitation, anion exchange chromatography, and further purified by gel-permeation chromatography (GPC). Their structural features were investigated by high performance liquid chromatography (HPLC), high performance gel-permeation chromatography (HPGPC), methylation analysis, periodate oxidation-Smith degradation, Fourier transform-infrared (FT-IR) and NMR spectroscopy, including two-dimensional (2D) NMR. HPLC analysis revealed that WPLE-N-1 was mainly composed of glucose (92%) with small amount of galactose (3.9%) and mannose (4.1%), WPLE-N-2 and WPLE-N-3 contained mannose-galactose-glucose in the molar ratio of 10:27:63 and 5:12:83, respectively. GPC and HPGPC showed that WPLE-N-1, WPLE-N-2 and WPLE-N-3 are homogeneous fractions and their molecular weights were estimated to be 757.5 kDa, 20.9 kDa and 4.7 kDa, respectively. Chemical and spectroscopic studies indicated that WPLE-N-1 consisted of (1→6)-β-D-glucopyranosyl residues; while WPLE-N-2 and WPLE-N-3 were found to contain (1→6)-, (1→4)- and (1→3)-α-D-glucopyranosyl residues, (1→6)-α-D-galactopyranosyl residues, (1→3,6)- and (1→2,4)-α-D-mannopyranosyl residues and terminal residues of D-glucopyranosyl residues. On a preliminary bioactivity test, these three polysaccharides exhibited antitumor activity against Sarcoma S-180, Carcinoma HCT-116 and HT-29 in vitro. This finding suggests that mannogalactoglucan should be explored as potential antitumor agents and utilized as tumor cell growth inhibitors for food and pharmaceutical industries.

The paper presents the work on manufacturing and preliminary characterisation of fibre reinforced composite honeycomb structured composites by 3D printing. The capabilities and limitations of the processing are discussed. The work aims to compare the effectiveness of reinforcement using specimens of similar dimensions produced on the same machine and characterise them. Initially, tensile performance of unprinted fibre and printed fibre has been evaluated. Challenges associated with the testing of the printed specimens are addressed. Bend testing will follow to assess the performance as a composite structure to assess the interaction between fibre, matrix and core. Continuing work is planned to compare the effect of other parameters such as fill pattern and fill density to assess their effect on the composite.

Panax ginseng C. A. Meyer is a well-known plant medicine in the world. Ginseng polysaccharides mainly contain starch-like glucan and pectin. In this paper, a novel glucan WGPA-UH-N1 was purified from ginseng pectin by the treatment of de-esterification and endo-polygalacturonase, followed by the chromatographies on DEAE-Sepharose Fast Flow and Sephadex G-50 column. WGPA-UH-N1 has molecular weight about 17 kDa. WGPA-UH-N1 was determined to be a linear α-(1 → 6)-D-glucan without side chains by FT-IR, 13 C-NMR, 1 H-NMR, HMQC and HMBC spectra. It is the first time to isolate a linear α-(1 → 6)-D-glucan from Panax ginseng C. A. Meyer. Immunological activity assays showed that WGPA-UH-N1, although not effective on the phagocytosis of macrophage, could significantly induce lymphocyte proliferation without mitogenic stimuli at 1.0 mg/mL or with LPS at 0.5 mg/mL, also significantly increase NO production at the range of 0.1–1.0 mg/mL in a dose-dependent manner. The immunological activities of WGPA-UH-N1 are different from those of the β-(1 → 6)-D-glucan (BIWP2) isolated from the fruit bodies of Bulgaria Inquinans (Fries).

Voids and porosity are critical imperfections in fibre reinforced composite materials. The aim of this study is to assess the comparative accuracy and reliability of conventional and novel void characterisation techniques for analysing voids within carbon fibre reinforced composite (CFRC) laminates. While microscopy and Archimedes density measurements can only give results of limited accuracy and reliability, micro-computed tomography (micro-CT) analysis was found to have no significant inherent errors and is able to characterise the three-dimensional size, shape and distribution of voids in CFRC laminates. The accuracy of micro-CT was also verified by analysing artificial voids of a known size and shape disbursed throughout a CFRC laminate sample.

In this article, three bio-composites, i.e. flax, linen and bamboo fabric reinforced epoxy resin, were manufactured using a vacuum bagging technique. The influence of alkali treatment (with 5 wt% NaOH solution for 30 min) on tensile properties of flax, linen and bamboo single-strand yarns, surface morphology and mechanical properties (with respect to tensile and flexural properties) of the composites were investigated. It was found that the failure mechanism of single-strand fibres under tension consists of fibre breakage and slippage simultaneously. The alkali treatment had a negative effect on the tensile strength and modulus of the flax, linen and bamboo single-strand yarns. However, after the treatment, the tensile and flexural properties of all the composites increased, e.g. the tensile and flexural strength of the treated flax/epoxy composite increased 21.9% and 16.1%, compared to the untreated one. After the treatment in all the composites, the tensile fractured surfaces exhibited an improvement of fibre/epoxy interfacial adhesion.