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Graphene is one atom thick two dimensional material with unusual mechanical, electrical, thermal and optical properties. Graphene, on larger scale is produced through reduction of graphene oxide which in turn is synthesized by chemical oxidation of graphite. Generally large area graphene oxide paper can be easily fabricated by solution filtration process, spin casting method and Langmuir-Blodgett assembly. In present study graphene oxide was synthesized by modified Hummers method. Free standing graphene oxide paper (GOP) was developed by simple drying of graphene oxide suspended in water followed by reduction by thermal treatment to synthesize free standing conducting graphene paper (Thermally Reduced Graphene Paper, TRGP). Thermal reduction was carried out for 30, 60, 90 and 120min and samples referred as TRGP_30, TRGP_60, TRGP_90 and TRGP_120 respectively. XRD results show decrease in inter layer spacing (d002) from 0.87 nm to ∼0.35 nm after reduction of GO paper. This shows gradual removal of oxygen fu...

In the present paper, the effects of cake thickness and time on the efficiency of brown stock washer of the paper mill are studied by using mathematical model of pulp washing for the species of sodium and lignin ions. The mechanism of the diffusion‐ dispersion washing of the bed of the pulp fibers is mathematically modeled by the basic material balance and adsorption isotherm is used to describe the equilibrium between the concentration of the solute in the liquor and concentration of the solute on the fibers. To study the parametric effect, numerical solutions of the axial domain of the system governed by partial differential equations (transport and isotherm equations) for different boundary conditions are obtained by the “pdepe” solver in MATLAB source code. The effects of both the parameters are shown by three dimensional graphical representation as well as concentration profiles.

The Fourier Transform Raman and infrared spectra of cheque paper document have been recorded and analyzed. The wavenumbers corresponding to normal modes of vibration of cellulose were calculated at HF/6‐31G(d) level for comparison with the cheque paper sample. The appearance of a carbonyl stretching band at 1654 cm−1 clearly shows that the cheque paper is subjected to ageing. The broadening of O–H stretching wavenumber confirms the presence of inter and intra molecular O–H⋯O Hydrogen bonds. Also the presence of Kaolin and Rosin are unambiguously identified.

Soft plate‐like membranes find application e.g. as pill or paper coatings, bio‐filter membranes, and gas seals in food products. For these applications the integrity and the mechanical properties of the membrane are important. Mechanical properties of these products can be determined by stretching or bending tests, but such methods can damage these fragile products. We propose a rapid nondestructive acoustic method to estimate mechanical film characteristics with shear horizontal (in‐plane shear) waves. A 23 kHz, 1‐cycle square signal was excited into a thin foil with a piezoceramic pickup and received with an inductive pickup. The SNR (power) was 20 dB in 1 kHz –50 kHz bandwidth. This actuation‐detection scheme can be used to excite in‐plane longitudinal, shear and even elliptic waves in a thin foil. The method was validated by measuring in‐plane shear wave and longitudinal wave time‐of‐flight TOF at different actuator‐receiver separations and calculating the corresponding longitudinal and shear modulus. The samples were Mylar® sheet and coated paper. The anisotropy of MOE for Mylar sheet was close to the manufacturer specifications. For coated paper a maximum shear modulus anisotropy of 5% and a shear modulus dependence on temperature of 0.7 MPa/°C were found. Laser doppler vibrometry showed that the excited waves were confined in‐plane.

The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that use a magnetic field. The applications for magnetic sensors that have been studied include 1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, 2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and 3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.

In response to published reports about the decline in funding for space nuclear power, the Board of Directors of the American Institute of Aeronautics and Astronautics (AIAA) approved a position paper in March 1995 that recommends (1) development and support of an integrated space nuclear power program by DOE, NASA and DoD; (2) Congressional support for the program; (3) advocacy of the program by government and industry leaders; and (4) continuation of cooperation between the U.S. and other countries to advance nuclear power source technology and to promote safety. This position paper has been distributed to various people having oversight of the U.S. space nuclear power program.

A recent technology has been introduced into the paper industry that makes possible to produce paper materials by replacing the cellulose fibres by a mineral powder, achieving a more environmentally friendly product compared with conventional paper. The purpose of this work is to determine the possibilities of an air-coupled ultrasonic technique to study this kind of new materials in order to develop an ultrasonic system useful for quality control for this industry. In particular, air-coupled ultrasonic spectroscopy is specially well suited to this kind of materials because of the fact that no coupling liquid and no direct contact with the sample is employed. A through transmission technique is employed and Fourier analysis is performed to obtain both magnitude and phase spectra of the transmission coefficient. Properties in the thickness direction as well as in the paper plane are investigated. Different paper grades (from 120 to 400 g/m2) provided by Terraskin have been studied. Very high attenuation coeficientes and very low propagation velocities (and hence elastic constant) are obtained, this can be explained by considering the large porosity of this material (about 50%) and the microstrucutre: solid grains in contact with a variable amount of polymeric resin partially filling the pore space.

Prior work has established the existence of a color-performance relationship in achievement contexts and has demonstrated its presence in some undergraduate course examinations. This study examines the manifestation of such a relationship in an introductory, 430-student, calculus-based electricity and magnetism course during which the paper color used in examinations was varied. In this report, we analyze three separate exams and differentiate between students’ multiple choice, written response, conceptual, and computational performances. Also considered are factors such as the time students require to complete exams and their confidence levels prior to and immediately following assessment. Performance in all categories appears to be independent of paper color.

Organic catalyst has recently been identified as the potential substitution for expensive platinum electrocatalyst for fuel cell application. Numerous studies have shown that the nitrogen-containing carbon nanotubes (N-CNT) can be synthesized through spray pyrolysis or floating chemical vapor deposition (CVD) technique using various type of organometallic as precursors. This paper presents the method of synthesis and the initial findings of the growth of N-CNT directly on carbon paper using a modified CVD technique. In this research, nickel (II) phthalocyanines (Ni-Pc) as precursor was dissolved in ethanol solvent, stirred and sonicated to become homogenized. The solution was poured into a bubbler and heated up to allow the mixture to vaporize. Subsequently, the solution vapor was flowed into the tubical reactor maintained at 900°C. Carbon paper sputtered with nickel nanoparticles was used as the substrate. The synthesized sample was examined through Field Emission Scanning Electron Microscopy (FESEM), At...

In this paper we present an application of two Computational Intelligence Algorithms, namely Particle Swarm Optimization (PSO) Algorithm and Differential Evolution (DE) for finding and optimal solution to two optimization problems that occur in a paper industry. The first problem deals with the economic optimization of a hypothetical but realistic Kraft pulping process and in the second problem we have considered the optimization of Boiler load allocation problem. Both the problems form an integral part of paper making process. The simulation results show the efficiency and time effectiveness of DE and PSO.

Deviations of the electron function velocity distribution from Maxwellian behavior in the high energy range have been extensively studied during the past two decades. A brief review of the experimental techniques and findings on the subject is given in this paper. There are indications that the electron distribution function in thermonuclear plasmas could be significantly different from the Maxwellian one even near the thermal velocity range when particular circumstances occur. These reasons motivate a renewed effort in the measurements that could detect low energies distortions, among which is the new Oblique Electron Cyclotron Emission diagnostics that has entered operations during 2006 experimental campaign at JET and aims to resolve relatively small differences in the ECE spectra taken at three toroidal angles. Such measurements allow insight into the characteristics of the electron distribution function. First results of such experimental system are discussed in this paper, along with emission simulations.

Due to the rising difficulty of developing complex systems a lot of research has gone into the multi‐agent paradigm over the past decades, during which a vast array of approaches for developing such systems have been proposed. Despite this fact there seems to be a gap in the MAS community between solutions that provide for expressivity and those that offer generality. It is our opinion that embedding the MAS language into a functional language we can have the best out of both worlds: we can implement the desired semantics in an abstract way, allowing us to focus on the problem domain, i.e. complex, distributed MAS. Our approach is going to be layered: (i) we start from a statically typed functional language and build an EDSL that acts as an executable specification language for single agent entities; and (ii) develop a framework for workflow‐oriented coordination on top of the previous layer and investigate its use as a means of implementing agent organizations, focusing on coordination and communication.

At the 2007 Physics Education Research Conference, a workshop on publishing and refereeing was held with a panel of editors from four different publishing venues: the physics education research section of the American Journal of Physics, the Journal of the Learning Sciences, Physical Review Special Topics–Physics Education Research, and the Physics Education Research Conference Proceedings. These editors answered questions from participants regarding publishing in their respective venues, as well as writing referee reports that would be useful to both journal editors and authors. This paper summarizes the discussion.

We verify simulation results indicating that carbon ion irradiation increases the stiffness of single wall carbon nanotube bucky paper (SWCNT). 4 MHz longitudinal and 15 MHz shear ultrasonic signals were transmitted by means of dry‐coupled acoustic horns through 40±4 μm thick samples and the time‐of‐flight (TOF) through the samples was measured. From the TOF the velocity of the wave was determined and the out‐of‐plane elastic and shear moduli were calculated. The nonlinearity parameter B/A for the irradiated and reference sample was measured. The results indicated a significant increase both in the shear modulus (90 %) and in the longitudinal modulus (69 %) for certain irradiation doses as predicted by simulations. In addition, a 36% increase in the acoustic nonlinearity parameter (B/A) was observed. The investigated fluence range was 1⋅1013 to 3⋅1014 cm−2.

For the paper industry, stiffness properties are an important parameter for producing more efficiently a fibrous material like paper. Some stiffness properties of paper webs can be obtained in a non‐contact fashion using two lasers. The authors have developed an automated laboratory laser‐ultrasonics instrument for paper, described here. The results of non‐contact laser generation and detection of ultrasound are also presented. The paper grades investigated were heavy grades like linerboard, as well as copy paper.

Acoustic emission experiments in paper, a disordered material, give evidence for power‐law probability distributions of statistical quantities as event energies or intervals. Two setups, usual mode I tensile tests and a nip‐in‐peel one have been studied in our work. In both cases, even using the same material, we observe “criticality”. This has wide implications for theories of statistical fracture.

An important material property in the paper industry is the anisotropic stiffness distribution due to the fibrous microstructure of paper. Ultrasonic methods offer a means of determining the stiffness of sheets of paper from the anisotropic propagation characteristics of elastic Lamb waves along the machine direction (MD) and the cross direction (CD). Currently, piezoelectric ultrasonic methods are employed in the industry to measure the elastic polar diagram of paper through multiple contacting measurements made in all directions. This paper describes a new approach utilizing the INEEL Laser Ultrasonic Camera to provide a complete image of the elastic waves traveling in all directions in the plane of the paper sheet. This approach is based on optical dynamic holographic methods that record the out of plane ultrasonic motion over the entire paper surface simultaneously without scanning. The full-field imaging technique offers great potential for increasing the speed of the measurement and it ultimately pr...

On-line measurement of material properties is a goal of many manufactures for production improvement and quality control. In the paper industry, the elastic stiffness of the paper web needs to be accurately measured and controlled online. Currently, contact ultrasonic methods are employed to measure the elastic constants of paper offline. Piezoelectric transducers are placed in contact with the paper surface to generate and detect plate wave modes, known as Lamb wave modes, in the paper in both the machine and cross directions. Laser ultrasonics offers a new approach to making elastic wave measurements that does not require contacting the paper web. A pulsed laser generates ultrasound in the paper by delivering a high intensity short impulse to the paper through thermoelastic expansion. An optical interferometer is used to demodulate the small phase modulation that the elastic wave produces on a continuous probe laser beam. Difficulty in applying this approach to online measurements of rapidly moving pape...

It has been hypothesized that high triggering doses of hyperoxaluria induce crystal formation, while lower maintenance doses promote crystal growth. We confirmed this using minipumps secreting 30 to 60 μmol potassium oxalate per day to induce modest, continuous hyperoxaluria for 28 days after the triggering dose (288 μmol oxalate) was given as an i.p. injection or infused over 24hr. Calcium oxalate crystal deposition was induced in 6/6 rats. This hypothesis could explain the modest clinical correlation between oxalate excretion and calcium oxalate stone disease.

The mechanical and electrical properties of a bulk material made of single wall carbon nanotubes (SWNT) are, due to weak intermolecular interaction, several orders of magnitude lower than those of the individual molecules themselves. We studied the effect of gamma‐irradiation on SWNT paper in air and under vacuum. For samples irradiated in air, changes in Young modulus and electrical conductivity were observed with maximum value for a dose of 170 kGy. Under vacuum there was only a small effect of irradiation. Raman studies of irradiated samples showed defects formation. Same experiments done with graphite showed similar results. A likely explanation of the results is that cross‐links between nanotubes were induced by irradiation in air.

In the 1933 Bohr and Rosenfeld’s famous article on electromagnetic field measurements they did not consider the measurement of a magnetic component in a given space‐time region, nor the measurement of two parallel magnetic components, nor the measurement of two non‐parallel magnetic components, nor the parallel measurement of one magnetic and one electric component, nor the non‐parallel measurement of one electric and one magnetic component, nor the non‐parallel measurement of one magnetic and one electric component in two different space‐time regions. This article covers the first one of these pending matters.

When the atomic physicist measures or computes, applications of their results may not be immediately obvious. However, atomic data form the basis of many mature and developing applications. Two of these applications and their dependence on data are reviewed here. In particular, the national standard for radiation exposure and the processing of the United States mail with radiation are discussed.

Microwave energy offers the drying/curing industry a new prospect in efficient and uniform drying. In paper drying, due to the fact that absorption power depends on loss factor, more heat is developed in wet areas thus resulting in automatic moisture profile correction. During drying the most important parameter is maintaining the pre-prescribed level of moisture content. The correlation equation between absorbed power and moisture contents has been developed, in order to program the controlling hardware related to the level of drying power.

Solar flares provide a unique site for the study of energy release and particle acceleration in astrophysics. This paper summarizes the charged particle and gamma ray aspects of the Workshop on High Energy Solar Physics held at the Goddard Space Flight Center in August 1995. The X‐ray aspects of the Workshop are summarized in another paper. Here are our highlights: (i) both the charged particle, and now also gamma ray observations have shown that stochastic acceleration due to gyroresonant interactions with plasma waves is very important in solar flares; (ii) CME driven shocks accelerate the particles observed in space from gradual flares; (iii) accelerated MeV/nucl ions can contain a large fraction of the energy released in flares; (iv) GeV ions are either trapped at the Sun or accelerated for hours; (v) nuclear gamma ray spectroscopy has become a tool for abundance determinations in the solar atmosphere; (vi) behind‐the‐limb flares can provide imaging information for solar gamma ray emission.