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Copyright of Arab International Journal of Digital Art & Designs is the property of Arab Institution of Knowledge Management and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rhipicephalus sanguineus can complete up to four generations per year, depending on factors such as climate and host availability. Biomorphic studies of R. sanguineus were conducted under laboratory conditions. The larval, nymphal and adult ticks were fed on sheep at 250C, 60 % relative humidity (RH) and exposed to daylight. The incubation period was lasted 35 days. The average mean of premoulting and moulting period of larvae was 70 ± 0.91 and 7.4 ± 0.6 days, respectively. The time durations of premoulting and moulting of nymphs were 62 ± 1.66 and 13 ± 6.4 days, respectively. The average developmental periods were 6.09, and 5.15 days for larval pre-feeding, and feeding, respectively. The average developmental periods were 3.54, and 6.11 days for nymphal pre-feeding, and feeding, respectively. The complete life cycle of R. sanguineus was 180 days with range of 120-286 days. The average weights of the unfed larvae, and nymphs were 0.04 ± 0.03, and 0.40 ± 0.09 mg, respectively while 0.60 ± 0.05, and 5.02 ± 0.20 mg for engorged larvae and nymphs, respectively. The index of reproduction efficiency (REI), egg production efficiency (EPE), and the index of reproductive fitness (RFI) averaged 14.99 ± 3.65, 0.31 ± 0.08, and 11.74 ± 3.01, respectively. Scutum length and width of male was 2.2 and 1.2mm, respectively while length and width of female was 1.04 and 0.99 mm, respectively. The current study findings could help the workers in adopting different management studies for ticks in the world.

Copyright of Düzce University Journal of Forestry / Düzce Üniversitesi Orman Fakültesi Ormancılık Dergisi is the property of Duzce University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

3D architecratured transition metal dichalcogenides constructed by atomically thin layers are appealing building blocks in various applications, such as catalysts, energy storage, conversions, sensors, and so on. However, the direct growth of 3D transition metal dichalcogenides architectures with high crystal quality and well‐controlled size/thickness remains a huge challenge. Herein, we report a facile, highly‐repeatable, and versatile chemical vapor deposition strategy, for the mass production of high‐quality 3D‐architecratured transition metal dichalcogenides (e.g., MoS2, WS2, and ReS2) and their alloys (e.g., WxMo(1–x)S2 and RexMo(1–x)S2) nanosheets on naturally abundant and low‐cost diatomite templates. Particularly, the purified transition metal dichalcogenides products exhibit unique and designable 3D biomorphic hierarchical microstructures, controllable layer thicknesses, tailorable chemical compositions, and good crystallinities. The weak interlayer interactions endow them with good dispersity in solutions to form stable additive‐free inks for solution‐processing‐based applications, for example, high‐permeable and high‐stable separation membranes for water purification, and efficient electrocatalysts for hydrogen evolution reactions. This work paves ways for the low‐cost, mass production of versatile transition metal dichalcogenides powder‐like materials with designable structures and properties, toward energy/environmental‐related applications and beyond. [ABSTRACT FROM AUTHOR]

Copyright of Architectus is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The SEM image data presented in this article was collected by the Scanning electron microscopy (SEM) performed on an XL-30 ESEM FEG scanning electron microscopy. The diameter stastics data was collected and calculated by the Image-Pro Plus software system. The UV–Vis Res spectrum was collected by solid state UV diffuse reflector Shimadzu UV-4100 at wavelength 200–800 nm. The SEM image data showed more details of the poplar tree leave template(PTLT). The diameter stastics data show the diameter averagely distributed in the material. The UV–Vis Res spectrum reflected the physical property of PTLT NiO/ZnO. Interpretation of this data can be found in a research article titled “One-step facile synthesis of a NiO/ZnO biomorphic nanocomposite using a poplar tree leaf template to generate an enhanced gas sensing platform to detect n-butanol” (Qingrui Zeng et al., 2019) [1], Research Article DOI: 10.1016/j.jallcom.2019.05.018

Abstract Cork templates were used to produce lightweight bulk biomimetic ecoceramic (environmentally conscious ceramic) monoliths. Bulk/monolithic ceramics are vital for many applications, i.e. energy materials and fuel cells. Using simple and flexible, aqueous green-chemistry procedures, for the first time the influence of infiltration regime, number of infiltration cycles and sintering temperature on ecoceramic density and microstructure was studied. This lightweight three-dimensionally ordered macroporous (3DOM) CeO 2 preserved the hexagonal cellular structure of cork, but unlike the wood, the rear cell walls were open, greatly increasing open porosity. Higher sintering temperatures (1600 instead of 1000 °C) were required to produce cm size monolithic ecoceramics mechanically strong enough to be handled. The infiltration regime and number of infiltration cycles affected density and porosity. Lower infiltration pressure led to higher porosity ecoceramics (3.3–5.7%), which may favour catalytic performance, showing the possibility of tailoring porosity and specific surface area by modifying the number of infiltration cycles. [ABSTRACT FROM AUTHOR]

Biomorphic charcoal/TiO2 composites (C/TiO2) from moso bamboo templates were produced for absorbing microwave. Subsequently, the characteristics of the C/TiO2 were investigated by scanning electron microscopy, thermogravimetric analysis, and vector network analysis. The results showed that the biomorphic microstructure of the moso bamboo charcoal was duplicated in the C/TiO2. Thus, the density of the C/TiO2 sintered at 1200 °C was lower and approximately 0.916 ± 0.003 g/cm3. Moreover, the ignition, the maximum combustion, and the burnout temperatures of the C/TiO2 sintered at 600 °C were ~320 °C, ~530 °C, and ~585 °C, respectively. Additionally, with the rising of the temperature sintering C/TiO2, the microwave absorbency of the C/TiO2 was improved over high frequency zones. Furthermore, the average imaginary-part values of the permittivity of the C/TiO2 sintered at 600 °C and 1200 °C notably increased by 11.16-fold. In addition, the peak of microwave reflection loss of the samples (2.0 mm thickness) from the C/TiO2 powder (wt. 20%) sintered at 1200 °C and the paraffin wax (wt. 80%) was observed as -18.0 dB at 17.4 GHz. Therefore, the C/TiO2 sintered at higher temperatures exhibited lower geometrical density, better thermostability, and favorable microwave absorptive properties.

Materials development is driven by microstructural complexity and, in many cases, inspired by biological systems such as bones, shells and wood. In one approach, one selects the main microstructural features responsible for improved properties and design processes to obtain materials with such microstructures (continuous-fibre-reinforced ceramics, porous ceramics, fibrous ceramic monoliths, etc.). In a different approach, it is possible to use natural materials directly as microstructural templates. Biomorphic ceramics are produced from natural and renewable resources (wood or wood-derived products). A wide variety of SiC-based ceramics can be fabricated by infiltration of silicon or silicon alloys into cellulose-derived carbonaceous templates, providing a low-cost route to advanced ceramic materials with near-net shape potential and amenable to rapid prototyping. These materials have tailorable microstructure and properties, and behave like ceramic materials manufactured by advanced ceramic processing approaches. This review aims to be a comprehensive description of the development of bioSiC ceramics: from wood templates and their microstructure to potential applications of bioSiC materials. [ABSTRACT FROM AUTHOR]

The “Sonar Hopf” cochlea is a recently much advertised engineering design of an auditory sensor. We analyze this approach based on a recent description by its inventors Hamilton, Tapson, Rapson, Jin, and van Schaik, in which they exhibit the “Sonar Hopf” model, its analysis and the corresponding hardware in detail. We identify problems in the theoretical formulation of the model and critically examine the claimed coherence between the described model, the measurements from the implemented hardware, and biological data.

Biomorphic nano-hydroxyapatite (HAP) was fabricated by a co-precipitation method using cotton as bio-templates and employed in adsorptive removal of ofloxacin (OFL) and triclosan (TCS) that are two representative pharmaceuticals and personal care products (PPCPs). The surface area and porosity, crystal phase, functional group, morphology and micro-structure of the synthesized HAP were characterized by Brunauer–Emmett–Teller isotherm, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron macroscopic and transmission electron microscopy. The effects of initial pH, ionic strength, initial concentration, contact time and temperature on the removal of PPCPs were studied in a batch experiment. The adsorption of OFL and TCS was rapid and almost accomplished within 50 min. Kinetic studies indicated that the adsorption process of OFL and TCS followed the pseudo-first-order and pseudo-second-order models, respectively. The Freundlich isotherm described the OFL adsorption process well but the adsorption of TCS fitted the Langmuir isotherm better. Thermodynamics and isotherm parameters suggested that both OFL and TCS adsorption were feasible and spontaneous. Hydrogen bond and Lewis acid–base reaction may be the dominating adsorption mechanism of OFL and TCS, respectively. Compared to other adsorbents, biomorphic HAP is environmentally friendly and has the advantages of high adsorption capacity, exhibiting potential application for PPCPs removal. [ABSTRACT FROM AUTHOR]

Biomorphic charcoal/TiO2 composites (C/TiO2) from moso bamboo templates were produced for absorbing microwave. Subsequently, the characteristics of the C/TiO2 were investigated by scanning electron microscopy, thermogravimetric analysis, and vector network analysis. The results showed that the biomorphic microstructure of the moso bamboo charcoal was duplicated in the C/TiO2. Thus, the density of the C/TiO2 sintered at 1200 °C was lower and approximately 0.916 ± 0.003 g/cm³. Moreover, the ignition, the maximum combustion, and the burnout temperatures of the C/TiO2 sintered at 600 °C were ~320 °C, ~530 °C, and ~585 °C, respectively. Additionally, with the rising of the temperature sintering C/TiO2, the microwave absorbency of the C/TiO2 was improved over high frequency zones. Furthermore, the average imaginary-part values of the permittivity of the C/TiO2 sintered at 600 °C and 1200 °C notably increased by 11.16-fold. In addition, the peak of microwave reflection loss of the samples (2.0 mm thickness) from the C/TiO2 powder (wt. 20%) sintered at 1200 °C and the paraffin wax (wt. 80%) was observed as -18.0 dB at 17.4 GHz. Therefore, the C/TiO2 sintered at higher temperatures exhibited lower geometrical density, better thermostability, and favorable microwave absorptive properties. [ABSTRACT FROM AUTHOR]

Biomorphic SiC (bioSiC) materials fabricated by silicon infiltration of chescoal preforms have been studied. As a result of this process, a porous SiC ceramics with remnant silicon partially filling pores is obtained. This remnant silicon can considerably alter the mechanical properties of the bioSiC but it can be effectively removed by reaction with a mixture of HF and HNO3 producing a clean pororus bioSiC. In this work the comparison of the mechanical properties of bioSiC from preforms of beech, eucalyptus and pine, with and without remanent silicon is studied. High temperature mechanical properties were studied from deformation tests in compression at constant strain rate. Microstructural characterization of the samples, before and after the mechanical tests, was performed by scanning electron microscopy (SEM).Se han estudiado carburos de silicio biomórficos (bioSiC) fabricados mediante infiltración reactiva de silicio líquido en una preforma de carbón de origen vegetal. Se obtiene así una cerámica porosa de SiC con silicio remanente en sus poros. Este silicio puede alterar considerablemente las propiedades mecánicas de los bioSiC. Este trabajo preliminar se centra en el estudio de las propiedades mecánicas de los bioSiC fabricados a partir de preformas de haya, eucalipto y pino, tras reacción con una disolución de HF y HNO3 que elimina ostensiblemente el silicio residual. Las propiedades mecánicas a altas temperaturas fueron estudiadas a partir de ensayos de compresión a velocidad de deformación constante. La caracterización microestructural del material resultante, antes y después de los ensayos mecánicos, fue realizada mediante Microscopía Electrónica de Barrido (MEB).

This work is devoted to the study of the time and temperature dependence of the static grain growth in YTZP 4 mol %, with an average grain size within the submicrometric range (> 0.1 μm). Also, the mechanical response in the temperature interval between 1200 ºC and 1500 ºC is analysed. The grain growth is controlled by the yttria segregation at the grain boundaries, which plays a key role in the cationic diffusion processes. Microstructural characterization of both as-received and deformed samples allows to conclude that plastic deformation is due to grain boundary sliding (GBS), with stress exponents increasing with the flow stress, but in all cases they are lower than n = 2.Una posible aplicación del SiC biomórfico (bioSiC) son los reforzante estructural en hormigones refractarios. En este caso se han fabricado piezas de bioSiC con forma de cilindros alargados, 3-4 mm de diámetro y 30-35 mm de longitud, mediante infiltración reactiva de Si líquido en piezas de carbón obtenidas por pirolización de madera de haya de calidad comercial. Hemos estudiado las características microestructurales y las propiedades mecánicas de los reforzantes, como paso previo al estudio de la aplicación mencionada, de la que se ofrece un avance en este trabajo. Para caracterizar la calidad del material y del proceso de fabricación, la microestructura de las piezas se ha estudiado mediante microscopía electrónica de barrido. Los reforzantes de bioSiC fueron ensayados a compresión uniaxial y flexión en cuatro puntos a temperatura ambiente y a alta temperatura (1250-1400ºC) para la determinación de sus propiedades mecánicas, y se realizaron estudios fractográficos en el segundo tipo de ensayos. Subsecuentemente, se prepararon ladrillos refractarios con un 3% en peso de reforzantes de bioSiC, que fueron curados a diferentes temperaturas (máx. 1600ºC). Estos ladrillos se han ensayado en compresión y flexión en tres puntos, a temperatura ambiente, comparándose los resultados con los obtenidos en ladrillos sin reforzantes y reforzados con agujas metálicas de calidad comercial (acero refractario 306 ó 310), con la misma formulación y condiciones de curado.

There is an increasing interest in the fabrication of materials with biomorphic microstructure. In particular, the fabrication of biomorphic ceramics would be of high interest because its high-temperature structural applications. The ceramics presented in this research were fabricated by the pyrolysis and infiltration with molten silicon of wood preforms. The final product is SiC with the same microstructure of the wood precursor. Wood is a natural composite that present an anisotropic porous microstructure with excellent elasticity, strength, and damage tolerance. Some of this properties will remain improved in the ceramic product. Biomorphic ceramics reach high strengths (700 MPa at 1150 oC for biomorphic SiC made from eucalyptus wood). The influence of the wood precursor and fabrication process in the mechanical and microstructural properties has been studied. The correlation microstructure-mechanical properties is discussed, as well as the application of the cellular theory of solids.En los últimos años se ha puesto de manifiesto un considerable interés en la fabricación y optimización de materiales de microestructura biomórfica. En particular, la fabricación de cerámicas biomórficas es especialmente importante ya que éstas pueden ser utilizadas en aplicaciones estructurales a temperaturas elevadas. Los materiales objeto de esta investigación se fabrican mediante la pirólisis e infiltración de silicio fundido en preformas de madera. El resultado final es SiC con la misma microestructura que la madera precursora. La madera es un material natural compuesto que presenta una morfología porosa anisotrópica con una excelente elasticidad, resistencia y tolerancia al daño; algunas de estas propiedades se trasladarán y amplificarán al pasar a la cerámica que se elabora a partir de la misma. Se ha estudiado la influencia de la madera seleccionada y el proceso de fabricación en las propiedades mecánicas y microestructurales. Se ha podido comprobar la gran resistencia que presentan algunos de estos materiales (700 MPa a 1150ºC para cerámicas obtenidas a partir de madera de eucalipto). Se discute la relación microestructura-propiedades mecánicas y la aplicación de la teoría de materiales celulares al estudio de éstas.

Biomorphic cellular C/SiC–ZrC composite ceramics were fabricated from pine and oak wood precursors. Carbonaceous preforms were first prepared by wood pyrolysis and subsequently infiltrated with polyzirconobutanediol (PZC) and polycarbosilane (PCS) to form the composite ceramics. TGA/DTG and dilatometric analysis were used to study the pyrolysis of the wood precursor. XRD and SEM analyses were applied to characterize the microscopic properties of the resulting biomorphic cellular C/SiC–ZrC composite ceramics. Compared with oak, pine was preferable for preparation of cellular C/SiC–ZrC composite ceramics because of its unique microstructure. The SiC–ZrC phase distribution differed within the composite ceramics. In addition, the compression strengths of wood, charcoal, and cellular C/SiC–ZrC composite ceramics were measured in the axis direction. Results showed the improved compression strength of biomorphic cellular C/SiC–ZrC composite ceramics when the impregnation cycles were repeated. [ABSTRACT FROM AUTHOR]

Porous oxide ceramics are of special significance in various applications. Calcination of layered double hydroxides (LDHs) often produces very reactive mixed oxides with porous structures. In this work, we describe a biotemplate-assisted approach to fabricate hierarchically porous alumina-based ceramic composites. The porous architectures are designed by controllable growth of LDHs nanosheets on the inner and outer surfaces of morph-Al 2 O 3 in a closed hydrothermal system followed by calcination. The as-prepared alumina-based ceramics and corresponding design strategies developed herein are expected to be applicable to the synthesis of other porous oxide ceramics by utilizing biological structures. [ABSTRACT FROM AUTHOR]

Biomorphic CuO crystals with ordered hierarchical micro- and nanostructures were fabricated via a simple one-step thermal decomposition of CuSO4 ⋅ 5H2O precursor by using various biotemplates. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis spectrometer (UV-vis), Fourier transform infrared (FTIR) and Raman spectroscopy. The primary morphologies of the biomorphic CuO were determined on different biotemplates, and the size of the secondary CuO crystals was well controlled by the varying of calcination temperature. This simple thermal decomposition method provides a cost-effective and eco-friendly route for the preparation of metal oxide semiconductors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hierarchically structured Mg–Al composites were successfully prepared. [•] Multiscale architectures were fabricated by improved biotemplate method. [•] Crystal growth of LDHs was strongly dependent on urea content. [•] The biomorphic composites are quite effective in BSA adsorption. [ABSTRACT FROM AUTHOR]

An ideal scaffold in bone tissue-engineering strategy should provide biomimetic extracellular matrix-like architecture and biological properties. Poly(γ-benzyl-L-glutamate) (PBLG) has been a popular model polypeptide for various potential biomedical applications due to its good biocompatibility and biodegradability. This study developed novel bimodal porous PBLG polypeptide scaffolds via a combination of biotemplating method and in situ ring-opening polymerization of γ-benzyl-L-gIutamate N-carboxyanhydride (BLG-NCA). The PBLG scaffolds were characterized by proton nuclear magnetic resonance spectroscopy, X-ray diffraction, differential scanning calorimetry, scanning electron microscope (SEM) and mechanical test. The results showed that the semi-crystalline PBLG scaffolds exhibited an anisotropic porous structure composed of honeycomb-like channels (100–200μm in diameter) and micropores (5–20μm), with a very high porosity of 97.4±1.6%. The compressive modulus and glass transition temperature were 402.8±20.6 kPa and 20.2°C, respectively. The in vitro biocompatibility evaluation with MC3T3-E1 cells using SEM, fluorescent staining and MTT assay revealed that the PBLG scaffolds had good biocompatibility and favored cell attachment, spread and proliferation. Therefore, the bimodal porous polypeptide scaffolds are promising for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract: Biomorphic SiC composites were fabricated by infiltration of liquid Si into a preform fabricated from medium-density fiberboard (MDF). The phase compositions, microstructures, oxidation behaviors, and ablation properties of the composites were investigated. The composites were oxidized at elevated temperatures (up to 1450°C) in air to study their oxidation behavior. Pores and cracks initially formed from the oxidation of residual carbon, followed by melting of residual Si. The ablation resistance of a composite was gauged using an oxy-acetylene torch. The formation of a SiO2 layer by the oxy-acetylene flame improved the ablation resistance because molten SiO2 spread over the ablated surface and partially sealed the pores, thus acting as an effective barrier against the inward diffusion of oxygen. [Copyright &y& Elsevier]

Abstact: Biomorphic mesoporous MnO2 tubes were prepared by a simple impregnation of potassium permanganate solution on cotton template followed by calcination in air. The as-prepared MnO2 was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric–differential scanning calorimetry analysis (TG–DSC), N2 adsorption and desorption measurements and electrochemical workstation. The MnO2 tubes replicated the morphology of natural cotton and were composed of nanoparticles about 100nm in size. Compared with the bulk MnO2, which was obtained by the direct thermal-decomposition of MnO2 precursor, the biomorphic MnO2 tubes displayed much better pseudocapaictive properties due to the higher special surface area and the unique mesoporous structure. [Copyright &y& Elsevier]

Abstract: Hierarchically structured layered double hydroxides (LDHs), with special surface structural and positively charged layer, are of great interest due to their potential applications in bioseparation and catalysis. Herein this work presents a novel method for fabricating ZnnO composites derived from cotton fibers, as well as its application in bovine serum albumin (BSA) separation. The morphology and structure of as-prepared samples are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. It is found that the fibrous morphologies are retained in inorganic replicas, and the surface of composites is composed of many small nanosheets. Batch adsorption results indicated that the prepared samples were very effective in adsorbing BSA. Effects of solution pH, adsorbent dose, adsorption time, and adsorption temperature were investigated in detail. The equilibrium data were found to be well described by Dubinin–Radushkevich model, while the kinetic data were well-fitted to the intraparticle diffusion model. Based on the mechanism of adsorption, the adsorption sites of composites can be easily occupied by adsorbed high negative charge anions through electrostatic interactions. The BSA desorption can be controlled via the addition of salt solution. [Copyright &y& Elsevier]

A network of fibers comprising orthorhombic molybdenum trioxide (α-MoO3) crystals were synthesized using paper as template via a biomorphic approach. The template was completely removed by annealing the sample at 600°C for 5 min. Monoclinic MoO3 was formed and consequently converted into orthorhombic α-MoO3 after prolonged annealing. Three milligrams of the biomorphic α-MoO3 could degrade up to 90% of a methyl violet aqueous solution with a concentration of 20 mg/L under normal visible light. The size of the α-MoO3 grains and the porosity of the biomorphic sample affected catalytic performance. [ABSTRACT FROM AUTHOR]

Abstract: Biomorphic porous ZnO nanostructures were successfully synthesized via an aqueous sol–gel soaking process using pieces of apple flesh and skin as templates and employed for glucose direct electrochemical biosensor. The structure and morphology of ZnO nanostructures were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). By modifying glassy carbon electrode with the biomorphic ZnO nanostructures and Nafion, two glucose biosensors were constructed and their direct electrochemistry of glucose oxidase (GOD) was successfully investigated by cyclic voltammetry (CV). The biomorphic porous ZnO nanostructures using apple skin template (S-ZnO) were more effective in facilitating the electron transfer of immobilized GOD than that of using flesh apple template (F-ZnO). This may be a result of the unique morphology and smaller average crystallite size of the S-ZnO nanostructure. GOD immobilized on Nafion-porous S-ZnO nanostructure composite display direct, reversible, and surface-controlled redox reaction with a detection limit of 10μM, a response time of 7s, high sensitivity of 23.4μA/mMcm2 and a fast heterogeneous electron transfer rate with a rate constant (k s) of 3.9s−1. It was found that S-ZnO significantly has improved the direct electron transfer between GOD and glassy carbon electrode with good stability and reproducibility. [Copyright &y& Elsevier]

Abstract: Self-support porous biomorphic CuO/CeO2/Al2O3 catalysts with different elemental composition were synthesized by using cotton as template. The samples were characterized via SEM, nitrogen gas sorption surface analysis, XRD and Raman scattering. Their performances in catalytic CO oxidation were investigated. The samples consisted of network of mesoporous hollow fibers composing of nanometer-sized CuO, CeO2 and Al2O3 grains. We found that optimal CO oxidation was achieved by using the sample with Cu/Ce/Al weight ratio of 1/5/2. Low Cu content resulted in the formation of the CuCeO solution, the active component for CO oxidation. Small amount of alumina improved the catalytic activity because it promoted the oxygen diffusivity of ceria by reducing the size of ceria crystallites. The catalytic performance of the biomorphic product was compared with a control powder sample. The hollow fibrous structure of the product was found to enhance the catalytic activities by facilitating the passage for the flows of gaseous reactants. [Copyright &y& Elsevier]

Abstract: Biomorphic Al2O3 ceramics were prepared through the surface sol-gel process with filter papers as bio-templates. The filter papers were infiltrated with ?-AlOOH sol and subsequently sintered in air at high temperatures to produce the biomorphic Al2O3 ceramics. The results show that the final materials have a hierarchical structure originated from the morphology of cellulose paper. The sintering temperatures exhibit a strong effect on the surface pore-size distribution of obtained Al2O3 ceramics. Differential scanning calorimeter, scanning electron microscopy, X-ray diffraction and BET analysis were employed to characterize the microstructure, morphology and phase compositions of the final products. [Copyright &y& Elsevier]

Natural bone is an amazing material because of its structure and mechanics. It is a challenge to find a bone substituted material mimicking natural bone intended to suffice for the need for bone repair and regeneration. In this study, a biomorphic material with similar structure and mechanical properties of cancellous bone has been fabricated by using demineralized cancellous bone as a template. Well‐oriented particles in the pore walls could be observed clearly. The compressive strength of this scaffold was up to about 4.9±0.2MPa, close to the lower limit of the natural bone and 30 times of bioactive glass scaffolds, even though the porosity was up to 90%. This kind of bioactive glass composite scaffolds presented high resistance to deformation and showed an excellent shape restoration property. It is very close to a natural cancellous bone with a similar macro‐ and micro‐structure and force‐extension behavior. These results suggested this material would have a good potential in bone tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010. [ABSTRACT FROM AUTHOR]

Abstract: Long biomorphic ZnO hollow fibers with porous walls have been fabricated using cotton fibers as bio-templates. Cotton fibers are infiltrated with zinc acetate aqueous solution and subsequently calcinated in an air atmosphere at high temperatures to remove cotton templates. The as-prepared hollow fibers are as long as several centimeters and replicate not only macroscopic structure of the cotton fibers, but also microscopic morphologies. The calcinating temperatures in the fabrication process have great effects on the surface roughness and wall quality. [Copyright &y& Elsevier]

Abstract: A facile method to synthesize biomorphic N-doped TiO2 (N-TiO2) templated with cotton and further assemble Au nanoparticles within the nanopores is reported. Biomorphic N-TiO2 is synthesized through a one-step infiltration and calcination process with the aid of acetylacetone (acac) as a controlling agent to the hydrolysis and condensation of N-doped TiO2 precursor to make it depositing on the template. The doping N atoms are in the interstitial sites of TiO2 lattice and responsible for visible light sensitivity. The sizes of the nanopores of biomorphic N-TiO2 are mono-distributed, which results in Au nanoparticles with controlled narrow size distribution and high stability. The biomorphic Au/N-TiO2 shows an overall increasing in light absorption and prominent surface plasmon resonance (SPR) peak within visible range. [Copyright &y& Elsevier]

Biomorphic C/SiC composites were fabricated from different kinds of wood by liquid silicon infiltration (LSI) following a two-step process. In the first-step, the wood is converted into carbon preforms by pyrolysis in a nitrogen atmosphere. The carbon preforms are then infiltrated by silicon melt at 1,560°C under vacuum to fabricate C/SiC composites. The mechanical properties of the C/SiC composites were characterized by flexural tests at ambient temperature, 1,000, and 1,300°C, and the relationship between mechanical properties and microstructure was analyzed. The flexural strength of the biomorphic composites was strongly dependent on the properties of the carbon preforms and the degree of silicon infiltration. The flexural strength increased with increasing SiC content and bulk density of composite, and with decreasing porosity in the C/SiC composite. An analysis of fractographs of fractured C/SiC composites showed a cleavage type fracture, indicating brittle fracture behavior. [ABSTRACT FROM AUTHOR]

Abstract: Biomorphic Al2O3 templated with charcoal and cotton is synthesized respectively and Ag nanopaticles are further assembled in the nanopores of biomorphic Al2O3. The morphology and pore structure of biomorphic Al2O3 as well as the size and properties of embedded Ag nanoparticles are characterized by FESEM, TEM, XRD, nitrogen adsorption and UV–vis. Biomorphic Al2O3 with two different templates show differences in the nanopore structure, and within the same template, the nanopore structure is also influenced by different synthesizing conditions. The size and distribution of further assembled Ag nanoparticles are in accordance with that of the nanopores of biomorphic Al2O3, and the intensity and position of surface plasma resonance (SPR) effect of Ag nanoparticles are influenced by their size and interaction with biomorphic Al2O3 matrixes. [Copyright &y& Elsevier]

In this paper, cotton fibres were used as bio-template to successfully synthesize new ceramic materials, ZnO hollow fibres and in an effort to explore the synthesis condition, and simplify the synthesis procedure. In this synthesis, a direct thermal decomposition of zinc acetate dihydrate coated on the surface of cotton fibres was explored. The wall porosity of the ZnO hollow fibres was controlled by changing the concentration of zinc acetate aqueous solution. [ABSTRACT FROM AUTHOR]

Abstract: A simple and green technique has been developed to prepare hierarchical biomorphic ZnO, using eggshell membrane (ESM) as the template. ESM was infiltrated with zinc nitrate solution and subsequently sintered at high temperatures to produce the final ZnO interwoven nanofibers. Different from traditional immersion technics, the whole synthesis process depends more on the restriction or direction functions of the ESM biomacromolecules. The precision replication of natural biostructures can be achieved by the assembly of ZnO nanocrystallites about 5 nm. Consequently, the interwoven meshwork at three dimensions is formed due to the direction of biotemplate. The action mechanism is summarily discussed here. It may bring the biomorphic ZnO semiconductors with hierarchical interwoven structures to more applications, such as catalysts, photoelectrochemical devices, etc. [Copyright &y& Elsevier]

Abstract: SnO2 hierarchical films with interwoven tubular structures assembled by nanocrystallites have been achieved through a sol–gel approach combined with calcination treatment and involving eggshell membrane as a template. The gas-sensing property and the sensing mechanism have been studied from the sensor responses to ethanol, formaldehyde, liquefied petroleum gas, gasoline, and H2S species, based on the investigation of the crystallite size, specific surface area, and Raman surface vibration modes. It is investigated that as-synthesized SnO2 as a gas sensor has significant advantages attributable to the small nanocrystallite units and hierarchical assembly, which are mainly responsible for the surface activity of the SnO2 films and further influence on the gas sensing properties. [Copyright &y& Elsevier]

A simple, green and versatile route has been developed for the fabrication of hierarchical SnO2 via a soaking technique combined with a calcination treatment. The biomaterial eggshell membrane (ESM) is used as the template, and Sn(NO3)4 solution acts as the impregnant. As-prepared SnO2 nanoparticles assemble into tubular fibers, and further array into porous hierarchical meshworks to faithfully retain the morphology of the natural ESM. The sintering temperature has a significant effect on the morphology and surface pore-size distribution of the target material. [Copyright &y& Elsevier]

Abstract: Tissue engineering is a discipline at the leading edge of the field of computer assisted intervention. This multidisciplinary engineering science attempts to meet the reparative and regenerative needs of tissues and organs based on the notion of design and fabrication of scaffolds- porous, three-dimensional “trellis-like” biomimetic structures that, on implantation, provide a viable environment to recuperate and regenerate damaged cells. Existing scaffold fabrication strategies produce sub-optimal porous labyrinths with contra-naturam straight edges. The biomorphic geometry that mimics the secundam-naturam substrate would be one that is continuous through all space, partitioned into two not-necessarily-equal sub-spaces by a non-intersecting, two-sided surface. Minimal surface geometry is not only ideal to describe such a space but is also the preferentially assumed geometry in natural and pathological or manipulated cells. We present results on the premier attempt in computer-controlled fabrication, modulation, and mechanical characterization of tissue engineering scaffolds based on triply periodic minimal surfaces (TPMS). We also present novel strategies to realize coterminous seeding-feeding networks thereby guaranteeing blood/nutrient supply to the proliferating cells at close proximity. This initiative of linking Schwann’s 1838 cell theory with Schwarz’s 1865 discovery of TPMS is a significant step to fabricate the previously elusive optimal biomorphic tissue analogs. [Copyright &y& Elsevier]

Abstract: An investigation was made into the microstructure and high temperature mechanical properties of eucalyptus biomorphic SiC fabricated by pyrolizing a piece of eucalyptus wood and its infiltration with molten Si. The final product is a Si/SiC composite, which reproduces anisotropic microstructure of the wood. The elastic modulus was found to be constant up to 1000°C. The compressive strength decreased with the rise of temperature, but the flexure strength was constant up to 1350°C. At temperature close to the silicon melting point, the material strength was significantly reduced, the silicon phase has been alloyed to play an important role in carrying the load in compressive stress, but in flexure stress the silicon flows within the grain, reducing the connectivity in the SiC network. Residual carbon, oxidized at high temperature, creates voids that reduce the effective section and propagate internal cracks. The plastic deformation of Si at high temperature enhances the fracture toughness of the material. [Copyright &y& Elsevier]

Abstract: Biomorphic Al2O3 fibers have successfully been prepared using natural fibers of cotton as bio-templates. Cotton fibers are infiltrated with AlCl3 solution and subsequently sintered in air at high temperatures to produce the final Al2O3 fibers. The synthesized fibers faithfully retain the fibrous cotton morphologies, with the complete removal of the cotton body. The sintering temperatures adopted exhibit great effects on the surface pore-size distribution for the prepared Al2O3 fibers. [Copyright &y& Elsevier]

Silicon carbide-based, environmentally conscious, biomorphic ceramics were fabricated by the reactive infiltration of molten silicon into porous, carbonaceous preforms derived from pyrolysis of African Bubinga wood. The bulk microstructure and high temperature mechanical properties of these ceramics were studied. These biomorphic ceramics mimic the fibrous microstructure of the wood resulting in high strength and anisotropy. The compressive strength parallel to fiber direction, which is the growth direction of the tree, was 750 MPa at 1100 °C and 300 MPa at 1350 °C. The compressive strength perpendicular to fiber direction was 215 MPa at 1100 °C and 120 MPa at 1350 °C. These materials were joined using the ARCJoinT approach. The microstructure of the joints was studied by scanning electron microscopy and the high temperature strength was measured in compression, with the joint oriented 45° to the compression axis. The joined specimens had strengths from 615 MPa at 1100 °C to 250 MPa at 1350 °C when the fibers were parallel to the compression axis (forming 45° with the joint plane), which are about 20% lower than the strength of the bulk material in the same orientation. The strengths ranged from 373 MPa at 1100 °C to 175 MPa at 1350 °C when the fibers were forming 45° with the compression axis (perpendicular to the joint plane), which are lower than the average strength of the bulk material compressed axially and in the perpendicular direction. [Copyright &y& Elsevier]

Weakly electric fish hunt and navigate without visual cues by sensing perturbations of a self-generated electric field. The ability to detect, characterize and localize objects using electric fields is called electrolocation. This capability could be beneficial for underwater robots sent to explore dark aquatic environments, from those on Earth to those that might exist on other planets and moons such as Europa. Here we describe initial progress on the development of an artificial sensor array that could provide electrosensory capabilities to a submarine robotic explorer. The design of the sensor array and the associated signal processing algorithms are inspired by ongoing empirical and theoretical studies of signal detection, estimation, and active sensor positioning in weakly electric fish as they hunt for small prey. Here we describe a simple test setup consisting of a small electrosensory array and a robotic platform for controlling the movement of an electrolocation target. This system allows us to acquire and analyze electrosensory signals similar to those obtained a weakly electric fish. [ABSTRACT FROM AUTHOR]

Although future orbital facilities will have immense scale, details will require intricate operations in restrictive, confined quarters. LEMUR is a small, agile and capable six-legged walking robot that has been built at the Jet Propulsion Laboratory to perform dexterous small-scale assembly, inspection and maintenance. It is intended to expand the operational envelope of robots in its size class (sub-5 kg) through the flexible use of its limbs and effectors, as well as through the modular changeout of those effectors. In short, LEMUR is intended as a robotic instantiation of a six-limbed primate with Swiss Army knife tendencies. LEMUR's layout consists of six independently operated limbs arranged in two rows of three. The front two limbs have four active degrees of freedom while the rear four limbs have three each. Each limb is reconfigurable to allow the integration of a variety of mechanical tools. [ABSTRACT FROM AUTHOR]