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Hybrid polymer latex based on combination of organic-inorganic materials, poly(methyl methacrylate-co-butyl acrylate) (PMMBA) and organo-montmorillonite (OMMT) were synthesized via miniemulsion polymerization technique. Modification of montmorillonite (MMT) through the incorporation of myristyltrimethylammonium bromide (MTAB) into the clay's interlayer spaces were investigated by Small-Angle X-ray Scattering (SAXS), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Transmission Electron Microscopy (TEM). Barrier property and thermal stability of polymer latex film sample were investigated through its Water Vapor Transmission Rate (WVTR) and Thermogravimetric Analysis (TGA). The results indicated that addition of OMMT as filler in PMMBA increased the barrier property and thermal stability of the latex film. Addition of 8.0% (wt) OMMT increased the barrier property and thermal stability. Miniemusion polymerization process with higher addition (>8.0 wt%) of OMMT resulting in high latex viscosity, particle size, and high amount of coagulum. The utilization of this hybrid polymer could benefits paper and board industries to produce high quality barrier paper for food packaging.

The carbon composite papers were produced by utilizing carbon materials from coconut coir. In the present work, carbon composite papers (CCP) were prepared by mixing carbon materials in the form of powder and fibre with polymer (ethylene vinyl acetate and polyethylene glycol) in xylene at 100°C. Then, polytetrafluoroethylene (PTFE) with different content was used to treat the surface of CCP. The properties of PTFE-coated CCP were analysed by means of contact angle measurement, tensile testing, porosity, density, and electrical conductivity measurements. As expected, all CCP's surfaces treated with PTFE were found to be hydrophobic with contact angle >120° and relatively constant during 60 minutes measurement. Furthermore, water contact angle, density, and mechanical properties of CCP generally increase with increasing PTFE content. However, the porosity and electrical conductivity of CCP decrease slightly as the PTFE content increased from 0 wt% to 30 wt%. Based on the observation and analysis, the optimum PTFE content on CCP was 20 %, in which the mechanical properties and hydrophobicity behaviour were improved significantly, but it was only caused a very small drop in porosity and electrical conductivity

By screening through test, it was found that the drug-loaded chitosan microspheres with the average particle size of 615 nm may be prepared with NaF as the mold-proof drug, chitosan as the drug carrier and sodium tripolyphosphate as the cross-linking agent; and they can improve the aspergillus niger-proof effect if loaded onto the base paper surface of the paper-based PVC wallpaper. The results show that NaF and chitosan have mold-proof synergistic effects; the mold-proof effect of the wallpaper may be improved by increasing the dose of chitosan; when the mass ratio of NaF, sodium tripolyphosphate and chitosan was 2:7:28, the paper-based PVC wallpaper with good mold-proof property can be prepared.

Current chromatography methods used for radiochemical purity test of 131I-Hippuran is time consuming. Therefore, in this study we explored several static and mobile phases in order to have a chromatography method which is accurate and efficient or less time consuming. In this study, stationary phases (Whatman-1, 31ET, and 3MM papers) and several mobile phases were explored to separate 131I-Hippuran from its impurity (131I iodide ion). The results of this study showed that the most efficient chromatography system for measurement of radiochemical purity of 131I-Hippuran was by using Whatman-31ET paper and n-butanol: acetic acid: water (4:1:1) as a static phase and mobile phase respectively. Developing time for this method was of approximately 75.7 ± 2.7 minutes. The result of radiochemical purity (%RCP) of 131I-Hippuran measured with this chromatography system either using Whatman-1 or Whatman-31ET paper strips was 98.7%. The short size of Whatman-31ET paper strip (1 x 8 cm) was found to have shorter developing time compared to that of long size paper. This system showed a good separation of 131I-Hippuran from its impurities and gave %RCP of 98.1% ± 0.04% with developing time approximately 44.3 ± 9.4 minutes. The short size of Whatman-31ET paper strips was found to be more efficient compared to that of Whatman-1 and Whatman-3MM paper strips in term of developing time.

In the paper, existing research and operating experience was summarized. On the basis, the particularity of oil-paper insulation operation condition for converter transformer was combined for studying the influence of temperature on oil-paper insulation field intensity distribution of converter transformers under different AC contents within wide temperature scope (-40°C~105°C). The law of temperature gradients on space charge accumulation was analyzed. The breakdown or flashover characteristics of typical oil-paper compound insulation structure under the action of DC, AC and AC-DC superposition voltage at different temperatures were explored. The design principles of converter transformer oil-paper insulation structures in alpine region was proposed. The principle was adjusted and optimized properly according to the operation temperature scope and withstood AC-DC proportion. The reliability of transformer operation was improved on the one hand, and the insulating medium can be rationally utilized for reducing the manufacturing cost of the transformer on the other hand.

With the development of novel device applications, e.g. in the field of robust and recyclable paper electronics, came an increased demand for the understanding and control of IGZO Schottky contact properties. In this work, a fabrication and characterization of flexible Ru–Si–O/IGZO Schottky barriers on paper is presented. It is found that an oxygen-rich atomic composition and microstructure of Ru–Si–O containing randomly oriented Ru inclusions with diameter of 3–5 nm embedded in an amorphous SiO2 matrix are effective in preventing interfacial reactions in the contact region, allowing to avoid pre-treatment of the semiconductor surface and fabricate reliable diodes at room temperature characterized by Schottky barrier height and ideality factor equal 0.79 eV and 2.13, respectively.

Flame spread behavior on combustible solid is one of important research related to Fire Safety Engineering. Now, there are a lot of combustible solid composed from mixed materials. In this study, experiments have been conducted to investigate flame spread behavior over combustible solid composed by paper, bagasse and mixed paper/bagasse. Experimental data is captured by using video recording and examined flame spread shape and rate. From the results obtained, shows that the different materials produce different flame spread shape and rate. Different flame shape is seen between all types of samples. Flame spread rate of 100% paper is faster than the one of 100% bagasse. Based on the result, it is also inferred that the material composition can be influenced on the flame spread shape and flame spread rate of mixed paper/bagasse.

We describe a method for fabricating paper-based microfluidic devices using a commercially available CO2 laser system. The method is versatile and allows for controlled through-cutting and ablative etching of nitrocellulose substrates. In addition, the laser system can cut a variety of components that are useful in the fabrication of paper-based devices, including cellulose wicking pads, glass fiber source pads and Mylar-based substrates for the device housing.

Cellulose-based electro-active paper (EAPap) has been reported as a smart material that has merits in terms of light weight, dry condition, biodegradability, large displacement output and low actuation voltage. However, it requires high humidity. This paper introduces an EAPap that can be actuated in low humidity conditions. The fabrication process and performance test of the EAPap actuator are illustrated. Cellulose fibers were dissolved in N,N-dimethylacetamide/lithium chloride. The solution was cast and immersed in water to form the cellulose film, followed by adding glycerol and lithium chloride aqueous solution, and drying in air. Depositing thin gold electrodes on both sides of the cellulose film made a bending EAPap actuator. Effects and optimum values of the glycerol content and the thickness of the films are discussed.

Reduction of graphene oxide is primarily important because different reduction methods may result in graphene with totally different properties. For systematically exploring the reduction of graphene oxide, studies of the temperature-dependent electrical properties of graphene oxide (GO) are urgently required. In this work, for the first time, broadband dielectric spectroscopy was used to carry out an in situ investigation on the transition of the electrical properties of GO paper from -40 to 150 °C. The results clearly reveal a very interesting four-stage transition of electrical properties of GO paper with increasing temperature: insulator below 10 °C (stage 1), semiconductor at between 10 and 90 °C (stage 2), insulator at between 90 and 100 °C (stage 3), and semiconductor again at above 100 °C (stage 4). Subsequently, the transition mechanism was discussed in combination with detailed dielectric properties, microstructure and thermogravimetric analyses. It is suggested that the temperature-dependent transition of electronic properties of GO is closely associated with the ion mobility, water molecules removal and the reduction of GO in the GO paper. Most importantly, the present work clearly demonstrates the reduction of GO paper starts at above 100 °C.

Present work reports the green synthesis of highly stable, non-toxic, environmental friendly, fluorescent carbon quantum dots (CQD) via simple synthetic route using the waste carbon paper as their precursor. The as-synthesized CQD were post-synthetically modified with (3-Aminopropyl)triethoxysilane (APTES) as a nitrogen source for amine functionalized CQD (NCQD) formation. When excited at wavelength λex = 350 nm, the maximum emission intensity of NCQD was observed at wavelength λem = 450 nm. The QDs show blue colored luminescence with significant photoluminescence quantum yield (~5.1%). Transmission electron microscopy and Energy-dispersive x-ray spectroscopy data show their size about 4.8 nm and the presence of nitrogen in elemental composition respectively. XRD and selected area electron diffraction patterns reveal their amorphous nature. This NCQD based sensing probe selectivity displays the high sensitivity for trinitrotoluene (TNT) in 4.4 nM to the 26.4 μM range. The probe delivers a 7.4ppb detection limit at 1.3% relative standard deviation.

The strength of concrete mix is dependent on many parameters like cement type, coarse aggregate and the interface between aggregate and mortar. However, generally the coarse aggregate is treated as an inert material and only its physical properties like shape, size, water absorption and specific gravity are studied. Whereas, as we increase the quality of mortar mix, the strength of coarse aggregate also comes into picture. In case of high performance concrete, the type of coarse aggregate used has a great influence on the strength and elasticity modulus of concrete. For high strength concrete with compressive strength above 40 MPa, which are generally cast with water-cement ratio less than or equal to 0.4, the strength of mortar and the interfacial bond strength may be comparable to the strength of aggregate. This paper presents a comprehensive review of the past research work done on the effect of using different types of coarse aggregate on various properties of concrete mix like its compressive strength, tensile strength and elasticity modulus.

We report the realization of a resettable resistive switching device based on a nanostructured film fabricated by supersonic cluster beam deposition of gold clusters on plain paper substrates. Through the application of suitable voltage ramps, we obtain, in the same device, either a complex pattern of resistive switchings, or reproducible and stable switchings between low resistance and high resistance states, with an amplitude up to five orders of magnitude. Our device retains a state of internal resistance following the history of the applied voltage similar to that reported for memristors. The two different switching regimes in the same device are both stable, the transition between them is reversible, and it can be controlled by applying voltage ramps or by mechanical deformation of the substrate. The device behavior can be related to the formation, growth and breaking of junctions between the loosely aggregated gold clusters forming the nanostructured films. The fact that our cluster-assembled device is mechanically resettable suggests that it can be considered as the analog of the coherer: a switching device based on metallic powders used for the first radio communication system.

We study how paper microstructure heterogeneity affects the electrostatic field acting on toner particles during xerographic printing. We use an efficient multigrid Poisson solver to simulate electrostatic fields. The dielectric distribution of paper is obtained either analytically or input numerically using a recently developed 3D fibre network model of paper. Simulations are used to elucidate the relative importance of paper surface, filler and porosity variations in establishing spatial variations of the electrostatic field. It is found that only long wavelength variations of surface height, bulk filler or porosity variations affect variations in electrostatic transfer forces to any relevant degree. Furthermore, we show that the effect of these long wavelength perturbations can be modelled using a new 1D effective capacitor model. When surface variations and surface filler are mixed together, we found the interesting result that mode mixing can decrease the spatial fluctuations of the electric field. Finally, using simulated 3D paper webs, which mimic the properties of laboratory handsheets, we find that to lowest order surface roughness and not formation is responsible in controlling variations of the electrostatic transfer field, a result of importance in digital printing onto stochastic printing substrates, such as commercial paper.

A layer-by-layer (LbL) self-assembly of poly(3,4-ethylenedioxythiophene)?poly(styrenesulfonate) (PEDOT?PSS) on lignocellulose wood microfibres was used to make conductive fibres and paper. Polycations such as poly(allylamine hydrochloride) (PAH), and poly(ethyleneimine) (PEI) were used in alternate deposition with anionic conductive polythiophene (PEDOT?PSS) to construct the multilayer nanofilms on wood microfibres. Current?voltage characterization was measured on single fibres using a Keithley probe measurement system after deposition of every PEDOT?PSS monolayer to study the electrical properties of the coating. The conductivity of the microfibres increased linearly with increasing number of bilayers of PEDOT?PSS/polycation. The measured conductivities of the coated microfibres ranged from 1 to 10?S?cm?1. It was also observed that the conductivity of the fibres (i.e., coating of PEDOT?PSS) depends upon the type of polycations used to alternate with the polythiophene. In this work we have demonstrated successful scale integration from nano to micro and macroscale (nanocoating?microfibres?macropaper) in developing new paper material. The conductive paper that has been produced (and its fabrication method) can be used for the development of smart paper technology on monitoring of electrical, and optical/electrical signals.

Multi-walled carbon nanotubes (MWNT) and polyaniline are coated on an electro-active paper (EAPap) to improve the performance of the bending actuator, and its performance is tested. EAPap actuators made with cellulose paper have merits in terms of large bending displacement, ultra-lightweight, dryness, low actuation voltage and power consumption, low cost and biodegradability. However, the force output of actuators is small and the actuation frequency is low. Thus, MWNT and emeraldine salt polyaniline (PANI) are coated on the EAPap material to improve the force and the actuation frequency. The MWNT and PANI solution is made by sonication, and the sonication time and the weight per cents of the MWNT and PANI are optimized to improve the hybrid actuator performance. The optimum condition is associated with conversion of the partial conductive state PANI into the emeraldine formed PANI by the chemical bonding between the MWNT and PANI. The performance improvement of the EAPap actuator coated with MWNT/PANI is investigated in terms of displacement, blocking force and efficiency. In the presence of an electric field (0.35 V µm−1) on the hybrid EAPap actuator, 250% of the output force, 160% of the resonance frequency and 50% of efficiency are improved.

A micro-patterning technique regarded as micro transfer printing is studied for gold electrode patterning on cellulose electro-active paper (EAPap), aiming at biodegradable and flexible MEMS fabrication. EAPap is known as a smart material due to the interesting actuation phenomenon of cellulose paper. Accordingly, EAPap can be used for sensor and actuator devices. Since EAPap is made with cellulose, a biodegradable and flexible MEMS device can be made with this material. However, since cellulose-based EAPap is hydrophilic and flexible, conventional lithography and etching techniques cannot be used for micro-patterning. This paper reports a new micro-patterning technique using the micro transfer printing (MTP) method on flexible EAPap material. The MTP technique consists of a master fabrication, a polydimethylsiloxane (PDMS) stamp construction, and a micro pattern transfer. Details of the technique and key issues are addressed. To demonstrate the feasibility of the MTP technique, a gold electrode pattern for a surface acoustic wave (SAW) MEMS device and a gold micro-strip pattern for a microwave dipole rectenna are made on cellulose paper substrates.

Electro-active paper (EAPap) is attractive as an electro-active polymer (EAP) actuator material due to its low weight, dry condition, large displacement output, low actuation voltage and low power consumption and biodegradability. EAPap is made from cellulose. Cellulose fibre is dissolved into a solution and made into a sheet, then thin electrodes are deposited on the cellulose paper to make an EAPap actuator. The performance of EAPap actuators was evaluated in terms of tip displacement, blocking force and electrical power consumption. The maximum tip displacement of 4.3?mm was obtained from a 40?mm long EAPap actuator when 0.25?kV?mm?1 was applied. This actuation voltage is quite low compared with other electronic EAP materials. The effect of the environment in terms of humidity and temperature was also investigated. When the relative humidity was increased up to 95%, the tip displacement increased. When the temperature was increased the displacement slowly increased and then gradually decreased after the temperature reached 30??C. These measurements were performed under a variety of environmental and input factors including frequency, actuation voltage, temperature and humidity.

Due to the highly light scattering nature of paper, the imaging depth of optical methods such as optical coherence tomography (OCT) is limited. In this work, we study the effect of refractive index matching on improving the imaging depth of OCT in paper. To this end, four different refractive index matching liquids (ethanol, 1-pentanol, glycerol and benzyl alcohol) with a refraction index between 1.359 and 1.538 were used in experiments. Low coherent light transmission was studied in commercial copy paper sheets, and the results indicate that benzyl alcohol offers the best improvement in imaging depth, while also being sufficiently stable for the intended purpose. Constructed cross-sectional images demonstrate visually that the imaging depth of OCT is considerably improved by optical clearing. Both surfaces of paper sheets can be detected along with information about the sheet's inner structure.

Signals of an optical coherence tomograph from paper samples are calculated by the Monte Carlo method before and after the action of different immersion liquids such as ethanol, glycerol, benzyl alcohol, and 1-pentanol. It is shown within the framework of the model used that all these liquids reduce the contrast of the inhomogeneity image in upper layers of the samples, considerably improving, however, the visibility of lower layers, allowing the localisation of the rear boundary of a medium being probed, which is important for precision contactless measuring a paper sheet thickness, for example, during the manufacturing process. The results of calculations are in well agreement with experimental data.

To develop a novel observation system for water accumulation and freezing in gas diffusion layers (GDLs) of polymer electrolyte fuel cells (PEFCs), phase-contrast X-ray imaging using the diffraction-enhanced imaging (DEI) technique was performed at temperatures between 233 and 293 K. The use of high-energy X-rays of 35 keV in the DEI technique enabled the visualization of ice and meltwater in carbon paper sandwiched by two Al plates of 0.50 mm thickness. It was proven that the DEI technique using a temperature-controlled chamber enables in situ observation of ice and water in GDLs under different temperature conditions, which is critical for achieving high performance PEFCs.

Transformer failure caused by the corrosion of copper material in transformer attracts great attention of researchers and engineers. In this paper, Karamay No. 25 naphthenic mineral oil, Karamay No. 25 paraffinic mineral oil, Kraft paper and copper were used to compose four combinations of oil-paper insulation samples. The ageing by-products and dielectric properties of the four combinations of oil-paper insulation samples were compared after they were thermally aged at 130°C. The influence of copper on the by-products and dielectric properties of different oil-paper insulations was obtained. The results show that copper can accelerate the ageing rate of insulation oils and reduce their AC breakdown voltage. The content of copper substance dissolved in insulating oil increases with ageing time at firstand then decreases. The paper aged in the oil-paper insulation sample with copper has higher moisture content than the one without copper. Results of energy dispersive spectroscopy (EDS) in the scanning electron microscope (SEM) show that there is copper product deposited on the surface of insulation paper. The insulation oil and paper aged in the oil-paper insulation sample with copper have higher dielectric loss and conductivity than that without copper.

We focused on the off-state current (I off) of oxide semiconductor thin film transistors (TFT) (In–Ga–Zn-oxide TFTs), which is lower than that of amorphous silicon TFTs and successfully made a prototype of a 6.0-in. extended graphics array (XGA) reflective liquid crystal display (RLCD) panel integrally including a data selection demultiplexer and a scan driver and capable of displaying still images at 1/180 fps. When still images are displayed, the frame frequency can be set low. This means that the frequency of rewrites of image data is markedly reduced. This leads to the reduction in the power consumption of an LCD panel. Our panel can solve the problems of electronic paper displays: high drive voltage and difficulty of displaying moving images. Thus, our panel is suitable for electronic paper displays.

The fundamental air cavity mode (A0) of a violin was investigated from the viewpoint of its dependence on the opening area and shape by using holed sheets of paper. The dependences of the frequency response of the A0 cavity mode on the shape, opening area, and orientation of the openings were observed. It was also demonstrated that the change of the opening area of f-holes affects to the performed tone with an actual violin.

Actuators based on cellulose paper with conducting polymer (CP-EAPap) as an electrode material were constructed. The bilayer and trilayer types of actuators were fabricated by depositing conducting polypyrrole on one side and two sides of cellophane paper respectively, which was previously gold coated. By varying the deposition time, the electrode thickness was manipulated. The performance of these two types of actuators was compared with respect to humidity changes and thickness variation. The electrode thickness plays a key role in the displacement behavior of these types of actuators. The best performance at higher humidity is also characteristic of CP-EAPap actuators. The possible mechanism of actuation is addressed in this paper.

Some elements of the study of fibrous structure are presented in this paper. X-ray synchrotron microtomography is used to provide information about the three-dimensional structure. In this context a segmentation method is proposed to separate the different components of the porous material considered (paper).

This study proposes a new method for the characterization of paper surface and bulk structure: optical coherence tomography (OCT). Although having been used in medicine for years, this technique is still relatively unknown in the paper-making industry. First, we provide a brief description of a conventional PC-controlled measurement system for the OCT imaging of paper. In this set-up, a powerful superluminescent diode is used to illuminate a Michelson interferometer with a free-space configuration, and a piezo-transducer is placed in the optical delay line to modulate the measurement signal for optical heterodyne detection. The set-up is then applied to demonstrate the ability of the technique to visualize the surface structures of widely disparate paper samples using a single device. Next, the paper provides 3D images of a fibre network and of typical copy paper. The results prove that OCT is applicable not only to the 3D imaging of simple wood fibre networks, but also to the imaging of complex commercial paper, provided that an appropriate clearing agent is used. Finally, the effect of filler on the OCT signal slope calculated by averaging several A-scans from the sample is demonstrated, showing that increasing filler content produces a corresponding decrease of decay of the A-scan in depth.

We introduce a method to measure paper wetting based on the measurement of monochromatic (670 nm) light transmission through paper. The samples were 49.8–51.7 g m−2 handsheets, the hydrophobicity of which was tuned by the fibre content of the furnish. In addition, one of the samples was internally sized. Impact wetting with isopropanol and water mist pulses was applied. The duration of a pulse was 100 ms, and the amount of liquid per pulse was 12.6 ± 1.2 g m−2. Optical changes in a paper sample were detected by measuring the average intensity of transmitted light through a selected area. The results showed that different wetting processes (pure capillary and combined capillary and diffusion wetting) could be distinguished from each other. With the presented method, differences in the individual behaviour of the samples during wetting could also be seen.

Multi-walled carbon nanotube (MWNT)-mixed cellulose electro-active paper (EAPap) was fabricated and its bending actuation performance and characteristics were tested. Cellulose fibers were dissolved using DMAc solvent and MWNT were mixed by using sonication. The very fine surface of DMAc cellulose film was fabricated using an in situ pressurized hydrolysis process. By mixing a small amount (0.1 wt%) of MWNT in the DMAc cellulose, enhancement of the MWNT-mixed cellulose EAPap actuator was demonstrated in terms of Young's modulus, resonance frequency and mechanical power output. The actuation principle of the actuator is also discussed.

Micro-contact printing (μ-CP) and liftoff techniques were employed to fabricate Au micro-patterns onto electro-active paper (EAPap) for biodegradable and flexible microelectromechanical system (MEMS) application. Conventional lithography and etching techniques cannot be utilized to fabricate micropatterns on EAPap having interesting actuating properties due to its hydrophilic and flexible characteristics. The cause of nanodefects on the Au pattern after the μ-CP process was investigated to enhance the pattern quality. Three different solvents were utilized to investigate the consequence of the solvent polarity during the 3-mercaptopropyltrimethoxysilane (MPTMS) self-assembled monolayer (SAM) fabrication and after the μ-CP process. The defects, such as microcracks and nanograins, were closely related to the solvent polarity. The higher polar solvent turned out smaller defects than the lower polar solvent due to the reduction of the solvent swell onto the PDMS stamp during SAM layer formation. The liftoff technique exhibited a new way of fabricating various metal patterns on EAPap without any nanodefects.

New methods for measuring barrier properties against solvents, acids and bases on dispersion coated paper were developed and investigated. Usability, reliability and repeatability were compared both between the new methods and with the standardized method for measuring barrier properties against water vapor. Barrier properties could be measured with all methods and the results obtained by the different methods were in correlation with each other. A qualitative method based on a trace color provided an indicative result, whereas further developed methods also took into account the durability. The effective barrier lifetime could be measured by measuring the conductivity through the substrate as a function of time, or by utilizing a glass prism where the change in refractive index caused by penetrated liquid was monitored, also as a function of time. Barrier properties against water and humidity were also measured and were found not to be predictors for barrier properties against either solvents, or acids or bases, which supports the need to develop new methods.

We propose a new display mode using a fast-moving ball actuator (FMBA) for reflective electronic paper displays. To realize ball position stability, we developed a triangular wedge-shaped electrode instead of a conventional plane electrode. Using the wedge-shaped electrode we could achieve position stability of the ball and the operation voltage decreased from 60 to 40 V. Since the microballs move one by one, not collectively, the FMBA is free from agglomeration or lateral diffusion. Using the ball-by-ball display mode, the FMBA can achieve a fast response of less than 0.2 ms, as can be seen in quick-response liquid power displays (QR-LPDs). The FMBA can also provide a high resolution of displays over 6350 pixels per inch (PPI) for a pixel size of less than 4 µm and a ball of diameter of less than 1 µm. It is a major advantage for achieving a minute pixel size owing to the use of ball-by-ball displays.

C-MnO2 was synthesized by direct hydrothermal decomposition of KMnO4. The structure and morphology of C-MnO2 was characterized by XRD and SEM, electrochemical performances were investigated by cyclic voltammetry. The effects of hydrothermal temperatures, and time were systemat ically investigated. The XRD pattern can be identified as a α-types space group, and it matches well with Bragg reflection of the standard α-MnO2, suggesting that a targeted α-MnO2 has been successfully synthesized. The results show that pure phase MnO2 nanorods can be obtained in 160 °C. C-MnO2 composites show a larger current response and C-MnO2 composite material has improved the efficiency of the large current charge and discharge.

A model for gloss is developed for surfaces with two-scale random roughness where one scale lies in the wavelength region (microroughness) and the other in the geometrical optics limit (macroroughness). A number of important industrial materials such as coated and printed paper and some paints exhibit such two-scale rough surfaces. Scalar Kirchhoff theory is used to describe scattering in the wavelength region and a facet model used for roughness features much greater than the wavelength. Simple analytical expressions are presented for the gloss of surfaces with Gaussian, modified and intermediate Lorentzian distributions of surface slopes, valid for gloss at high angle of incidence. In the model, gloss depends only on refractive index, rms microroughness amplitude and the FWHM of the surface slope distribution, all of which may be obtained experimentally. Model predictions are compared with experimental results for a range of coated papers and gloss standards, and found to be in fair agreement within model limitations.

Cellulose based electro-active paper (EAPap) has been discovered as an attractive EAP material for artificial muscles due to its advantages in terms of light weight, biodegradability, low cost, large displacement output, low actuation voltage and low power consumption. However, EAPap exhibits low force output and frequency band. To enhance EAPap actuators, a hybrid EAPap actuator is developed by coating a composite of single-walled carbon nanotube (SWNT)/polyaniline (PANi) with different dopants (Cl− and ClO4−). SWNT is dispersed in 1-methyl-2-pyrrolidone (NMP), and the SWNT suspension is mixed and sonicated with dopants. The resulting solution is coated on both sides of EAPap by spin coating. The actuation performance of hybrid EAPap actuators is tested in terms of bending displacement, blocked force, mechanical power output and electrical power consumption. The hybrid EAPap actuators show improved force and resonance frequency as a result of enhanced stiffness of the actuators. Although the displacement output is a little bit decreased, the required electrical field strength and the electrical power consumption are low, which are promising for achieving ultra-lightweight smart actuators.

This paper reports use of a nondestructive, miniaturized, microwave microstrip ring resonator for moisture sensing application in papers. Advantages offered by this sensor over the prevailing sensors are room-temperature operation, response time in milliseconds, measurements unaffected by dusty environment and ionic conductivity of samples. Samples of eleven types were tested, with grammage (grams per square metre) and thickness varying from 21 to 70 g m−2 and 24 to 80 µm respectively. The wet basis moisture normalization (with respect to instantaneous moisture content in the sample) was established to remove scatter and to bring out clearly grammage dependence, thus avoiding error in moisture prediction due to density variations, using only scalar measurements. A single equation for fr variations is realized in terms of grammage and normalized percentage moisture (Mww) which is valid for all types of tested paper. A model of the wet paper is suggested mainly based on water–dry paper interaction, also considering parameters like thickness and surface roughness, to explain trends of the sensitivity curves. The estimated %Mww shows an error of ±0.9% in the estimated value as compared to the actual value.

In this paper, the actuation mechanism of electro-active paper (EAPap) actuators is addressed and the potential of the actuators is demonstrated. EAPap is a paper that produces large displacement with small force under an electrical excitation. EAPap is made with a chemically treated paper by constructing thin electrodes on both sides of the paper. When electrical voltage is applied on the electrodes the EAPap produces bending displacement. However, the displacement output has been unstable and degraded with timescale. To improve the bending performance of EAPap, different paper fibers - softwood, hardwood, bacteria cellulose, cellophane, carbon mixture paper, electrolyte containing paper and Korean traditional paper, in conjunction with additive chemicals, were tested. Two attempts were made to construct the electrodes: the direct use of aluminum foil and the gold sputtering technique. It was found that a cellophane paper exhibits a remarkable bending performance. When 2 MV m-1 excitation voltage was applied to the paper actuator, more than 3 mm tip displacement was observed from the 30 mm long paper beam. This is quite a low excitation voltage compared with that of other EAPs. Details of the experiments and results are addressed.

In the first part of this work ultrasonic thickness resonances were measured with offset paper samples, 80-240 g m-2 in grammage. The resonance frequency was found to be linearly dependent on the grammage of the samples. In the second part of this investigation 240 g m-2 offset paper samples were wetted with a mist pulse of either water or isopropanol. This pulse, 61±4 ms in duration, was generated by a high-power ultrasonic actuator. The change in resonance frequency, initially 660±5 kHz, was monitored during the wetting of the paper sample. An ultrasonic burst, frequency swept from 500 to 900, 600 to 1000 and 1300 to 1700 kHz, was transmitted through the sample at a 10 Hz repetition rate. This made it possible to follow the wetting of the sample at several frequencies by the same measurement. It was also possible to follow the temporal development of the apparent absorption coefficient of the sample. The shape of the transmission curves suggests that two different processes, capillary wetting and diffusion wetting, can be distinguished.

Finding a low cost substrate for surface-enhanced Raman spectroscopy (SERS) yielding enhanced, reproducible Raman signal from Raman active samples has been a longstanding goal for researchers for years. Herein, we demonstrate the fabrication of such a SERS substrate from paper. The proposed paper-based SERS substrate was developed by attaching polyvinylpyrrolidone (PVP) capped silver nano-particles (AgNPs) to printing grade paper. The performance of the substrate has been evaluated for paper substrates of various grades (in grams per square meter; GSM). The usability of the developed substrate for detection of two Raman active samples—namely, malachite green (MG) and rhodamine6G (R6G)—is reported. In addition to these samples, the reproducibility of the designed substrate has been evaluated for 1,2-bis(4-pyridyl)ethylene (BPE); a good degree of reproducibility was observed. Finally, applicability of the proposed substrate for reliable detection of Raman signals from two more important samples—namely, glucose and urine—has been successfully demonstrated.

The use of starch as biodegradable base material for packaging application was of great interest as an environmentally friendly alternative to the present use of polyethylene and polyvinyl chloride. However, starch tended to be brittle and had a lack of stability due to exposure to water. Several aproaches have been done to improve shellac properties including through chemical modification, mixing with polymers, clays, and plasticizers. The present study related to optimization of starch properties when mixing with polyethylene glycol (PEG) coated on the paper. The aim was to obtain the temperature and mixing time between starch and PEG so produced composites with optimal barrier properties. The composites of PEG/starch 10 % w/w were prepared using solvent casting and coated on paper surface, and dried in the oven for 12 hours at 40°C. Water Vapour Transmitter Rate (WVTR) (Payne cup method) showed that 70°C was the optimum temperature when mixing time was 30 minutes. Moreover, it showed that the optimum mixing time was 30 minutes when mixing temperature was 80 and 70 °C. Fourier Transform Infra Red (FTIR) showed a strong interaction between PEG400 and starch.

The present study demonstrates an inkjet – printed interdigitated electrode array on paper substrate and its evaluation as humidity sensor. Inkjet droplet formation analysis has been performed in order to achieve repeatable results regarding generated droplets, based on the driving pulses applied on the inkjet piezoelectric element. Droplet formation has been monitored using stroboscopic effect. Three different paper substrates, namely high glossy inkjet photo paper, glossy inkjet photo and matte inkjet photo paper have been evaluated to investigate compatibility with the ink. Relative humidity measurements have been carried out in a controlled environment. Material degradation, long term response and memory effect are some of the aspects which were studied within the frame of the present work. The proposed sensor provides the opportunity for novel biomedical applications given the flexible substrate nature and the low – cost, single – step fabrication approach.