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The surface of filter paper was modified by an ecofriendly photografting process, carried out by using as modifiers commercial products based on fluorinated monomers with chain length ranging from C8 to C2. The grafting process was optimized mainly focusing on the properties conferred to the modified filter paper, that is hydrophobicity, oleophobicity and water-oil separation efficiency. The aim was to assess the influence of the chain length of the fluorinated monomer on the filter performance, evaluating the possibility to replace the long chain pollutant products with the safer ones.The surface of filter paper was modified by an ecofriendly photografting process, carried out by using as modifiers commercial products based on fluorinated monomers with chain length ranging from C8 to C2. The grafting process was optimized mainly focusing on the properties conferred to the modified filter paper, that is hydrophobicity, oleophobicity and water-oil separation efficiency. The aim was to assess the influence of the chain length of the fluorinated monomer on the filter performance, evaluating the possibility to replace the long chain pollutant products with the safer ones.

The work concerns the parameter estimation in the context of the mechanistic modelling of a pulp digester. The problem is cast as a box bounded nonlinear global optimization problem in order to minimize the mismatch between the model outputs with the experimental data observed at a real pulp and paper plant. MCSFilter and Simulated Annealing global optimization methods were used to solve the optimization problem. While the former took longer to converge to the global minimum, the latter terminated faster at a significantly higher value of the objective function and, thus, failed to find the global solution.The work concerns the parameter estimation in the context of the mechanistic modelling of a pulp digester. The problem is cast as a box bounded nonlinear global optimization problem in order to minimize the mismatch between the model outputs with the experimental data observed at a real pulp and paper plant. MCSFilter and Simulated Annealing global optimization methods were used to solve the optimization problem. While the former took longer to converge to the global minimum, the latter terminated faster at a significantly higher value of the objective function and, thus, failed to find the global solution.

Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

The pulp extracted from the alkaline peroxide pulping (APP) of EFB was beaten from 500 revolutions to 10000 revolutions using PFI mill to investigate the morphological changes undergone by the pulp and the resultant effect on paper sheet properties. As a result of beating, pulp elements were observed as intensely fibrillated, reducing the amounts of fibre bundles and thus, reducing interruption in the inter-fiber bonding. To a defined extent, beating was also seen as unwinding the structure of vessel element to a single strand of loose spiral body. These fibrillated vessel elements of APP pulp from EFB, plus the fines element germinating from further segmentation of the vessels, were the factors contributing to the overall strength improvement of the produced EFB pulp network. The applied increment in beating revolution had apparently widened the known broad spectrum quality of APP pulp from EFB. This demonstrates EFB potential for application in specialty paper production.

Biomass seems to have a great potential as a source of renewable energy compared with other sources. The use of biomass as a source of energy could help to reduce the wastes and also to minimize the dependency on non-renewable energy, hence minimize environmental degradation. Among other types of biomass, oil palm wastes are the major contribution for energy production in Malaysia since Malaysia is one of the primary palm oil producers in the world. Currently, Malaysia’s plantation area covers around 5 million hectares. In the oil palm mill, only 10% palm oil is produced and the other 90% is in the form of wastes such as empty fruit bunches (EFB), oil palm shells (OPS), oil palm fibre (OPFb) and palm oil mill effluent (POME). If these wastes are being used as a source of renewable energy, it is believed that it will help to increase the country’s economy. Recently, the most potential and efficient thermal energy conversion technology is pyrolysis process. The objective of this paper is to review the current research on pyrolysis of oil palm wastes in Malaysia. The scope of this paper is to discuss on the types of pyrolysis process and its production. At present, most of the research conducted in this country is on EFB and OPS by fast, slow and microwave-assisted pyrolysis processes for fuel applications.

Development of the desired pulp-based products eco-properties are governed by factors like choice and suitability of raw material, the design and operation of pulping process and choice of additives. Fines recovered during refining discharge of an alkaline peroxide pulping system were collected based on their retention on varying mesh-sizes screens. Analysis shows that 12% of the 400-mesh fines added to the web enhances paper tensile strength by 100%. This defines the usefulness of fibrillar particles whose cell wall collapsibility increases the web density by increasing bonding ability and thus, strength of pulp-based products such as paper. The study acknowledges fines functioning as natural filler in pulp network and collection of fines from the refining discharge was found to reduce 70% turbidity and this improvement will help reduce the costs pertinent to generation of whitewater from the pulping system.

EFB (empty fruit bunch) was subjected to alkaline peroxide pulping for generation of fibrous mass as raw material for the making of pulp-based products. During refining, co-produced fines were collected by fractionation on square-mesh screens of 200-, 250-, 300- and 400- mesh sizes, placed at the refining discharge by order of increasing mesh. Each set of the produced paper was incorporated with 12% fines for microscopic analysis. It appears that sheared vessel elements and fibrils were predominant and they make up the mass rendering collapsibility of cell wall for good product formation. The study acknowledged the form of fines functioning as natural filler in pulp network and worthy of utilization for reduction of total suspended solid.

Wastewater can be regenerated for recycling in an industrial process to reduce freshwater consumption and wastewater discharge. Such an environment friendly approach will also lead to cost savings that accrue due to reduced freshwater usage and wastewater discharge. However, the resulting cost savings are offset to varying degrees by the costs incurred for the regeneration of wastewater for recycling. Therefore, systematic procedures should be used to determine the true economic benefits for any water‐using system involving wastewater regeneration recycling. In this paper, a total cost accounting procedure is employed to construct a comprehensive cost model for a paper mill. The resulting cost model is optimized by means of mathematical programming to determine the optimal regeneration flowrate and regeneration efficiency that will yield the minimum total cost.

An innovative iron oxide embedded cellulose acetate membrane (FeO/CAM) was synthesized and used to study available phosphorus in Chinese lake sediments. The kinetics of available P release was investigated by FeO/CAM for different types of sediments ranging in Olsen-P from 19.1 to 170.6 mg/kg. The results showed that the average k{sub d} values (0.094 h{sup -1}) of the Taihu sediments were comparable to those of the soils with similar texture estimated by iron oxide impregnated filter paper (FeO paper) though they were generally lower than those of sandy soils. It is indicated that the FeO/CAM can be used as an infinite P sink to estimate available P (FeO-P). The concentrations of FeO-P were significantly correlated with those of extractable P forms, e.g. Olsen-P (R{sup 2} = 0.962, p

We describe the results of an expert system applied to the evaluation of samples of kaolin for industrial use in paper or ceramic manufacture. Different machine learning techniques—classification trees, support vector machines and Bayesian networks—were applied with the aim of evaluating and comparing their interpretability and prediction capacities. The predictive capacity of these models for the samples analyzed was highly satisfactory, both for ceramic quality and paper quality. However, Bayesian networks generally proved to be the most useful technique for our study, as this approach combines good predictive capacity with excellent interpretability of the kaolin quality structure, as it graphically represents relationships between variables and facilitates what‐if analyses.

This paper describes hundreds of pendulum tests examining the beamed energy conversion efficiency of different metal targets coated with multiple liquid enhancers. Preliminary testing used a local laser with photographic paper targets, with no liquid, water, canola oil, or methanol additives. Laboratory experimentation was completed at Wright‐Patterson AFB using a high‐powered laser, and ballistic pendulums of aluminum, titanium, or copper. Dry targets, and those coated with water, methanol and oil were repeatedly tested in laboratory conditions. Results were recorded on several high‐speed digital video cameras, and the conversion efficiency was calculated. Paper airplanes successfully launched using BEP were likewise recorded.

In this paper we have shown enhanced supercapacitive property of electrochemically reduced graphene oxide (ERGO) and manganese dioxide (MnO2) based heterostructure over single MnO2 thin film grown by electrochemical deposition on indium tin oxide (ITO). ERGO improves the electrical conduction leading to decrease of the internal resistance of the heterostructure.

This paper presents the preliminary transport measurements obtained using graphene quantum dots. Graphene quantum dots of 4.5 nm average diameter size prepared by electrochemical method are found to be of p-type nature under ambient condition. The p-type nature obtained is attributed to the physisorption of water molecules which acts a hole dopant.

The main purpose of this short paper is to present the Chernoff product formula from which we derive the exponential formula and the Lie-Trotter formula for C0-semigroups of linear operators on L∞.

The main purpose of this short paper is to introduce the evolution semigroup associated with an evolutionary process with exponential growth on L∞.

In this short paper, we present a Kato’s type inequality for symmetric diffusion operators.

Based on the concept of “using waste to treat waste and changing waste into valuables”, this paper put forward a new meso‐porous composite coagulant with good performance and low cost, and the removal effects of meso‐porous composite coagulant on algae cells and toxins, dissolved organics in water was studied, the object of this research was to provide a new and effective way for emergency needs to clear up harmful algal blooms in freshwater. The results showed that meso‐porous composite coagulant at optimal loadings (1g/L) could remove over 99% algal cells; meanwhile, the removal efficiency of COD, microcystin, total nitrogen and phosphorus was found to be 87.5%, 97.7%, 41.5% and 77.8% respectively, moreover, the forming speed of floccules was fast, and the dense floccules had good settling performance. Furthermore, the mechanism of algae removal was explored preliminarily by meso‐porous composite coagulant which played a dual role in adsorption and flocculation.

In this short paper we show the existence of solitonic solutions of four dimensional ungauged N = 1 supergravity coupled to arbitrary vector and chiral multiplets whose Ricci scalar curvature is constant. The Ricci scalar of spacetimes indeed depends on the σ‐model, namely the complex scalars and their first derivative. Then, we give two explicit models, namely static domain walls and static spherical symmetric black holes which are related to our previous works.

This paper assesses the performance of a thermophilic anaerobic Continuously Stirred Tank Reactor (CSTR) in the treatment of cassava stillage under various organic loading rates (OLRs) without suspended solids (SS) separation. The reactor was seeded with mesophilic anaerobic granular sludge, and the OLR increased by increments to 13.80 kg COD / m 3 / d (HRT 5d) over 80 days. Total COD removal efficiency remained stable at 90%, with biogas production at 18 L/d (60% methane). Increase in the OLR to 19.30 kg COD / m 3 / d (HRT 3d), however, led to a decrease in TCOD removal efficiency to 79% due to accumulation of suspended solids and incomplete degradation after shortened retention time. Reactor performance subsequently increased after OLR reduction. Alkalinity, VFA and pH levels were not significantly affected by OLR variation, indicating that no additional alkaline or pH adjustment is required. More than half of the SS in the cassava stillage could be digested in the process when HRT was 5 days, which demonstrated the suitability of anaerobic treatment of cassava stillage without SS separation.

It is well recognized that the macro‐scale response of soils is anisotropic in terms of strength, stiffness, permeability, etc. The source of this anisotropy is thought to be an anisotropy of the material itself. This anisotropy can be quantified using statistical methods if DEM numerical simulations or advanced experimental techniques are used. The anisotropic response of soil has been analyzed by many researchers in terms of the fabric tensor, which provides a measure of the orientation of the contacts between particles. Although many approaches for the quantification of the evolution of soil fabric have been used, they have not been previously compared to assess their effectiveness to describe fabric changes. A direct comparison of different methods of fabric quantification is presented in this paper based on the results from DEM simulations under different stress paths and the suitability of each of these methods is discussed. The results highlight the need for more accurate methods and/or approaches to accurately describe the evolution of fabric anisotropy in granular materials.

In this short paper we present a necessary and sufficient condition for that the one‐dimensional mass transport equation has one unique L1 weak solution.

Spectroscopic studies of comets were started at ARIES way back (some 35 years ago) and in this programme spectrophotometric observations of several comets were taken. The prominent emission features of CN (Δv = 0) at 3883A, C2 (Δv = +1, 0, −1) at 4695, 5165 and 5538A were detected. Weak emission features due to CH+C3 at 4050 A and C2 (Δv = −2) at 6190 A were also detected. Emission feature of NaD at 5890 A were also occasionally observed. In this paper dust and gas production rates for the emission features of CN (Δv = 0) at 3883 A, C2 (Δv = +1, 0, −1) at 4695, 5165 and 5538 A at different heliocentric and geocentric distances are presented.

Three industrial wastes arising from bleached hardwood kraft pulps, namely: unbleached screen rejects (USR), effluent treatment (ETW), and eucalyptus bark (EB) were analyzed with the aim of their possible valorization as an alternative source of cellulose. Their morphological properties were determined using MorFi apparatus. For this study the sample bleached kraft pulp, BKP, was analyzed as a reference. Lignin and carbohydrate contents were also quantified. These by‐products were studied as such (i.e. without careful purification) because we intended to find rational and low‐cost way of valorization. In fact any additional operation will induce an over cost. The results obtained indicate that these industrial wastes can be potential raw material in fibre‐based applications (paper, composites…), since they contain a high proportion of cellulose with preserved fibrillar morphology. Some of these materials have low lignin and inorganic residue contents.

The commercialization of medicinal plants and/or their products is highly increased in Romania lately. One of the most used herbs is sea buckthorn being well known for its quality with a large potential for curing some diseases. Sea buckthorn can be contaminated with undesirable microorganisms which may affect negatively its quality. The paper presents the results regarding the action of a non‐conventional technology meaning electron beam technique on sea buckthorn in order to improve its microbiological quality. Our study revealed that the sea buckthorn microbial load has been improved after 3 kGy irradiation keeping its active principles.

D meson 3‐body hadronic decay data in the past were analyzed with Breit‐Wigner amplitude fits. However, the complicated dynamics of the final states is known from previous studies to be poorly described by Breit‐Wigner models. This short paper discusses work within CLEO to use coupled channel techniques to describe these decays.

Non‐axisymmetric guided waves including flexural longitudinal and flexural torsional modes have shown natural focusing characteristics in pipe inspection. A flexural torsional mode theory was developed in this paper based on flexural longitudinal mode theory. Flexural mode experiments were then carried out to show the natural focusing phenomena.

Manganese oxide (Mn3O4) nanoparticles are prepared in a facile one pot reaction using oleylamine as solvent reducing and surface functionalizing agent. A simple mixture of as synthesized Mn3O4 nanoparticles and reduced graphene oxide are tested as potential supercapacitor using cyclic voltammetry. The voltammograms are nearly perfect rectangular which indicates excellent capacitive nature of the nanoparticles-grapheme composite. A maximum specific capacitance of 170 Fg−1 is obtained in a potential range from-0.1 to 0.7 V which is higher than both reduced graphene oxide and Mn3O4 nanoparticles.

Graphene is synthesized by microwave irradiation (MWI) of graphene oxide (GO) and subsequent sonication. MWI of GO is carried in a household microwave oven without using any reducing agents. Sonication of microwave irradiated GO is carried out in distilled water using a probe type sonicator. This method does not evolve any unsafe by-product gases which is otherwise the case when reducing agents are used in the reduction of GO to graphene. Moreover, due to its intrinsic nature, the method is scalable and cost effective. The synthesized product has been characterized as graphene using micro Raman scattering, x-ray diffraction and electron diffraction. Diffraction results show that the synthesized graphene is highly oriented.

The primary aim of the investigation is to synthesize graphene oxide at room temperature and fabricate a flexible free standing graphene oxide thin film. Modified Hummers technique was employed for the synthesis of graphene oxide using graphite as the starting material. Graphene oxide is a layered material consisting of hydrophilic oxygenated functional groups on their basal planes and edges. Graphene-oxide thin film has been fabricated via solvent-evaporation technique. Functional, elemental and structural analysis of the samples was performed using several characterization techniques.

Graphene provides a perfect platform to explore the unique electronic properties in two-dimensions. However, most electronic applications are handicapped by the absence of a semiconducting gap in pristine graphene. To control the semiconducting properties of graphene, doping is regarded as one of the most feasible methods. Here we demonstrate that graphene can be effectively doped during chemical exfoliation of highly ordered pyrolitic graphite in organic solvents. Layered structure of graphene sheets was confirmed by confocal Raman spectroscopy and doping was probed by analyzing shift in Raman peak positions and transistor transfer (IDS-VGS) characteristics.

Reduced graphene oxides were synthesized by chemical reduction of graphite oxide using hydrazine hydrate as well as by high temperature-high vacuum thermal exfoliation at 900-1100°C. The samples were characterized using Raman spectroscopy. From the Raman spectra, it is inferred that hydrazine reduced and thermally exfoliated samples were found to consist of two and three to five layers. The change in the amount of sp2 rings present in GO with increase in exfoliation temperature is studied.

Graphene/CeO2 quantum dots (QDs) composite was investigated towards the liquid petroleum gas (LPG) at room temperature. Graphene was synthesized by electrochemical exfoliation of graphite. The composites of graphene/CeO2 QDs was prepared by mixing 20 wt.% of graphene in constant 1g of CeO2. The chemiresistor of 20 wt.% composite possesses optimum value of sensing response and excellent stability.

In the present study, MnO2 nanotubes are synthesized by hydrothermal method and Pt/graphene by co reduction of hexachloroplatinic acid and graphite oxide. The formation of MnO2 nanotubes and Pt/graphene are confirmed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy. MnO2 nanotubes are mixed with Pt/graphene is applied as the ORR catalyst in proton exchange membrane fuel cell. The single cell measurement is carried out after fabricating the membrane electrode assembly and polarization curves are recorded at different temperatures and the results are discussed.

We report here a simple and efficient method for fabrication of reduced graphene oxide (rGO) thin films. Graphite oxide can be completely exfoliated to produce aqueous colloidal suspensions of graphene oxide (GO) sheets by simple ultra-sonication. Graphene oxide thin films were reduced towards graphene by exposure to hydrazine vapor, ammonia vapor and microwaves. The samples were characterized using X-ray diffraction (XRD) and UV-Visible spectroscopy (UV-Vis).

Graphene oxide monolayer sheets were transferred on Si and SiO2/Si substrates by Langmuir-Blodgett technique and were exposed to ammonia plasma at room temperature. The monolayer character of both graphene oxide and plasma treated graphene oxide sheets were ascertained by atomic force microscopy. X-ray photoelectron spectroscopy and Raman spectroscopy revealed that ammonia plasma treatment results in enhancement of graphitic carbon content along with the incorporation of nitrogen. The conductivity of graphene oxide monolayers, which was in the range of 10−6-10−7 S/cm, increased to 10−2-10−3 S/cm after the ammonia plasma treatment. These results indicate that the graphene oxide was simultaneously reduced and N-doped during ammonia plasma treatment, without affecting the morphological stability of sheets.

The large amount of graphene oxide was prepared by modified Hummers method, and which was then characterized by FT-Raman, FT-IR spectroscopy. Also the supercapacitor behavior of graphene oxide was studied ionic liquid. Here we observed that the graphene oxide shows best supercapacitor behavior in ionic liquid.