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Here, we report electronic properties of graphene field-effect transistor in a magnetic field of 9.0 tesla. Raman spectroscopy on graphene sample prepared by anodic bonding method shows it to be of the highest quality. The observation of charge neutrality point at a positive gate voltage is due to hole doping in the sample from the immobile oxygen ions created during anodic bonding process. Hysteresis observed in the longitudinal resistance (between source and drain) while sweeping voltage at gate in a loop may be due to high viscosity of polythene oxide matrix for mobile Li ions. The longitudinal resistance as a function of gate voltage Vg shows that both kind of charge carriers (electron and hole) can be doped in graphene, which is further ascertained by the Hall measurements.

Isotopic Ratio Mass Spectrometry (IRMS) is an effective toll to be used for drug product authentication. The isotopic composition could be used to assist in the differentiation between batches of drugs and assist in the identification of counterfeit materials on the market. Only two factors affect the isotopic ratios in pharmaceutical components: the isotopic composition of the raw materials and the synthetic processes performed upon them. Counterfeiting of pharmaceutical drugs threatens consumer confidence in drug products companies' economical well-being. In this preliminary study, the analyzed samples consist in two types of commercially available analgesics, which were purchases from Romanian pharmacies. Differences in δ13C between batches from −29.7 to −31.6% were observed, demonstrating that this method can be used to differentiate among individual drug batches and subsequently identify counterfeits on the market. On the other hand, carbon isotopic ratios differences among producers were recorded, t...

In our present work, we describe a simple method for uniform coating of Graphite oxide (GO) onto flexible polyurethane (PU) foams. These PU foams loaded with GO were made electrically conducting by converting insulating GO to conducting graphene by chemical reduction process without damaging the foam properties. These PU foams loaded with graphene were characterized by SEM and TGA. The morphology, thermal properties and pressure dependent electrical conductivity of these foams was studied. The electric current increased by five orders of magnitude due to applied pressure.

Composite materials were modified in order to increase their wear resistance when in contact with raw-cotton. It is found that the friction pairs increases their efficiency and durability to 2.0-2.2 times.

This work presents a preliminary study on the carbon isotope signature and trace metal content investigated on the soil-plant-fruit pulp chain. The samples were collected from two Transylvanian areas namely Alba and Salaj. The average value of the δ13C at the soil surface was around δ13C ≈ −27%o and important differences of the δ13C values between the two studied areas were not observed. Meanwhile, differences between fruit pulp of grape juice and the pulp of pear juice relived a difference of about 1.5%o for δ13C values.

The present study is focused on development of environmentally friendly intumescent/char forming coatings for wood and polymeric materials. For this purpose we have developed the method of oxidation of raw materials: polysaccharides, seeds and lignin by oxygen in the presence of catalyst. The main products of oxidation of such substrates are the salts of polyoxy- and polyphenoxy acids. The efficiency of fireproofing action of novel surface protecting intumescent coating for wood and polymeric materials based on modified renewable raw materials was studied. Flammability tests of wood and polymers samples treated by oxidized raw materials confirm their high-performance fire protection.

We summarize some current research on the formation and evolution of the universe and overview some of the key questions surrounding the the big bang. There are really only two observational cosmological probes of the physics of the early universe. Of those two, the only probe during the relevant radiation dominated epoch is the yield of light elements during the epoch of big bang nucleosynthesis. The synthesis of light elements occurs in the temperature regime from 108 to 1010 K and times of about 1 to 104 sec into the big bang. The other probe is the spectrum of temperature fluctuations in the CMB which (among other things) contains information of the first quantum fluctuations in the universe, along with details of the distribution and evolution of dark matter, baryonic matter and photons up to the surface of photon last scattering. Here, we emphasize the role of these probes in answering some key questions of the big bang and early universe cosmology.

The need to explore the use of renewable energy resources, in any way possible, is now considered as inevitable. The focus of this project is to utilize solar energy for the production of hydrogen from water. Both sunlight and water are available in abundance. As sunlight is available during day time, the photohydrogen produced can be stored and converted to electricity, whenever needed. The production of photohydrogen requires not only sunlight, but photocatalyst as well. A series of Ni/TiO2 photocatalysts with different Ni loading (2, 5, and 10 wt%) were prepared via wet impregnation method followed by calcination at 300°C for a duration of 2 hours. Hydrogen production from water was conducted by using a 250 W/m2 halogen lamp for one hour. The best performing photocatalyst was 10 wt% Ni/TiO2 giving 3.4 mL of hydrogen from H2O compared to the lower activity of TiO2 which produced only 1.9 mL of hydrogen from H2O. These values were obtained by using steady state light intensity; where else the available s...

Stable isotopes are now increasingly used for the control of the geographical origin or authenticity of food products. The falsification may be more or less sophisticated and its sophistication as well as its costs increases with the improvement of analytical methods. In this study 22 vegetable oils (olive, sunflower, palm, maize) commercialized on Romanian market were investigated by mean of δ13C in bulk oil and the obtained results were compared with those reported in literature in order to check the labeling of these natural products. The obtained results were in the range of the mean values found in the literature for these types of oils, thus providing their accurate labeling.

Graphene oxide sheets were transferred on Si and Ti substrates by Langmuir-Blodgett technique and were reduced by hydrazine vapor treatment followed by annealing in vacuum/inert atmosphere. A comparison of Raman spectra of reduced graphene oxide on Si and Ti shows that the reduction process is more effective in the later case and results in the formation of RGO with higher graphitic carbon content, exhibiting spectral features closer to those of graphene monolayers.

Ultrasound has been widely used for cleaning purposes in a variety of situations, including in dental practice. Cleaning is achieved through a combination of acoustically driven streaming effects and sonochemical effects arising from the production of inertial cavitation in a liquid. In our work, various dental instruments used for endodontic (root canal) treatment have been evaluated for their efficiency in producing sonochemical effects in an in-vitro cleaning environment. The areas where cavitation was produced were mapped by monitoring chemiluminescence from luminol solutions and this was correlated with their cleaning efficiencies - assessed by the ability to bleach a dye, to form an emulsion by mixing immiscible components and also to remove ink from a glass surface. The results showed good correlation (Pearson's coefficient > 0.9) between the cavitation and cleaning efficiencies, suggesting that the former plays an important role in cleaning. The methods developed and the results will be beneficial in endodontics research in order to optimise future root canal instruments and treatments.

This study examined some physical characteristics of laminated veneer lumber (LVL) obtained in different compositions from cut veneers of Oriental beech (Fagus Orientalis Lipsky) and Lombardy poplar (Populus nigra) with thicknesses of 4 mm and 5 mm. Five each beech and poplar trees were felled with this objective. The PVAc (Kleiberit 303) and PU (Bizon Timber PU-Max Express) types of adhesive were used in lamination. The air-dry and oven dry densities, cell wall density and porosity, the value of volume density, shrinkage in a tangential and radial direction and volume swelling amounts were determined by preparing the specimens in accordance with the standards.

The waste fly ash and shell fish are added to base material of cement (clinker, gypsum, trash and lime stone), for environmental reason. The ratio fly ash and shell fish was varied respectively 375:125; 250:250; 125:375, in grams weight for 2500 grams of total material. The chemical composition of raw material was determined by using x-rays fluorescence (XRF). Physical properties of sample match with Standar Nasional Indonesia (SNI). The physical properties of the best sample is made from composition of fly ash and shell fish as a substitution material on cement was 10% in weight, with ratio 250:250 in grams weight.

From the first-principle study, it is shown that the introduction of strain in a monolayer graphene enhances its chemical reactivity and hence it becomes more reactive than the pristine one. The intermolecular interaction between graphene and molecular hydrogen increases with increase in strain in the graphene plane leading to adsorption of hydrogen with suitable binding energy. Since graphene sheets can be freely suspended without any substrate we can stretch the sheets by adjusting distance between the clamped edges of the holding frame. In this way stacks of stretched graphene sheets can be constructed and a good hydrogen storage system can be obtained.

Few layer graphene (FLG) had been successfully grown on polycrystalline Ni films or foils on a large scale using DC Plasma Enhanced Chemical Vapor Deposition (DC PE‐CVD) as a result of the Raman spectra drawn out of the sample. The size of graphene films is dependent on the area of the Ni film as well as the DC PE‐CVD chamber size. Synthesis time has an effect on the quality of graphene produced. However, further analysis and experiments must be pursued to further identify the optimum settings and conditions of producing better quality graphene. Applied plasma voltage on the other hand, had an influence on the minimization of defects in the graphene grown. It has also presented a method of producing a free standing PMMA/graphene membrane on a FeCl3(aq) solution which could then be transferred to a desired substrate.

The micromechanically exfoliated monolayer graphene on SiO2, Al2O3, and HfO2 are investigated by Raman spectroscopy and AFM measurement. The pristine graphene seems to have stronger adhesion and higher carrier concentration when the dielectric constant of the underlying oxide is higher. It is found that high vacuum annealing significantly increases the interaction between graphene and the oxides and Raman G and 2D bands shift to higher wavelength. The high vacuum annealing for graphene on HfO2 increases carrier concentration of up to ∼10 times with a corresponding Fermi level shift of ∼0.65 eV although that of graphene on SiO2 induces a biaxial compressive stress as high as 4 GPa on graphene. As the three dielectrics evaluated in this work are the most commonly used gate dielectrics in field‐effect transistors, these findings will be useful in fabrication of graphene based field‐effect transistors.

During the last few years, due to the population explosion and the increased industrial activity, environmental pollution, has been pointed as one of the major problems of modern society. In this scenario, textile industry stands out as it produces a large amount of coloured dye effluents which are toxic and biodegradables [1]. Among the different types of dyes used in textile industry, 60–70% is azo compound. An extensive research on photocatalysis TiO2 has attracted significant attention for solving these problems due to its high potential for ensuring the complete destruction of organic compound in the aqueous medium [2–3].

Using the pulsed deposition technique, the growth of GaN on graphite substrate is possible. Because of the two‐dimensionality of graphite, the strain for the lattice mismatch due to the growth of GaN is absorbed by the topmost layer of graphite. We confirm that the electronic and the atomic structure for the interface of the grown GaN on graphite is almost similar to the interface of GaN on a single graphene layer using the density functional theory.

This study is focused on the drying pre‐treatment on whole empty fruit bunches [EFB] oil palm wastes. The drying process of whole EFB wastes by conventional method is investigated using the conventional oven in order to obtain less than 10 mf wt % moisture content. Normally, the biomass is dried to less than 10 mf wt % in most laboratory experiments and commercial processes for thermal conversion technologies such as pyrolysis. The result shows that the moisture content of EFB of less than 10 mf wt % is achieved after 29 hours of drying process.

The conventional deep desulfurization must be followed by a suitable desulfurization process to achieve ultra low sulfur diesel (ULSD) with 10–15 ppm sulfur level which satisfies the strict environmental regulations. Bio‐desulfurization is one of the potential routes for the above mentioned purpose. In this present investigation our major concern is production of Ultra Low sulfur diesel (ULSD) and production of biosurfactant simultaneously using Rhodococcus sp. The substituted benzothiophenes (BTs) and dibenzothiophenes (DBTs) get converted to 2‐hydroxy biphenyl, which is a potential bio‐surfactant. Kinetics of biodesulfurisation of deep desulfurized diesel using Rhodococcus sp. has been studied with special reference to removal of organo‐sulfur compounds in diesel and production of 2‐hydroxy biphenyl. The sulfur concentration of feed diesel is in the range of 200–540 mg/L. Aqueous phase to diesel ratios have been varied in the range of 9:1 to 1:9. The optimum ratio has been found to be 1:4 and the maximu...

From preliminary researches on a pilot scale, a complete demonstration plant was built to treat the effluents of a 30 pregnant sow’s piggery. It includes a screen, a vermifilter, a macrophyte lagooning, and a complementary water storage pond; the recycled water is used for flushing, and rainfall is collected to compensate for evapotranspiration. After functioning in 2008 and 2009, it was showed that, during the warm season, the whole plant produced an effluent suitable for flushing, where the concentration decrease was over 70% for the phosphorus and potassium, 95% for the COD and nitrogen, 99.8% for endocrine disruptors (estrogenic activity), and 99.99% for pathogenic micro‐organisms. During the cold season, the dilution by the rain water and the treatment effect of the constructed wetlands lead to similar results. Nevertheless, for this season, suitable floating macrophytes that will cover the lagoons remain to be settled.

Brine is usually exist in the oil reservoir. Varying salinity brine are used as stimulants for heavy oil recovery processes using electromagnetic induction heating. The heated heavy oil is floating on top of the brine since it becomes less viscous and lighter. As the temperature increased, more heavy oil is “produced/recovered”. An increasing salinity of brine will result in more recovery of heavy oil.

Acidithiobacillus thiooxidans was isolated from sewage sludge using the incubation in the Waksman liquor medium and the inoculation in Waksman solid plate. It was found that the optimum conditions of the bioleaching included solid concentration 2%, sulfur concentration 5 g⋅L−1 and cell concentration 10%. The removal efficiency of Cr, Cu, Pb and Zh in sewage sludge, which was obtained from waste treatment plant, Jinshan, Fuzhou, was 43.65%, 96.24%, 41.61% and 96.50% in the period of 4∼10 days under the optimum conditions, respectively. After processing using the proposed techniques, the heavy metals in sewage sludge did meet the requirement the standards of nation.

Membrane fouling due to foulants existing in the membrane feed water is an inevitable problem for ultrafiltration (UF) applied to water treatment. A bench‐scale study was undertaken to evaluate the anti‐fouling effect of different oxidants preoxidation on the dead‐end, constant flux UF of surface water. Furthermore, the mechanisms of membrane fouling by natural organic matter (NOM) were examined. The concept of UMFI (unified membrane fouling index) was applied to assess hydraulically reversible and irreversible fouling potential of UF membrane in the bench‐scale fouling studies. It was found that preoxidation greatly impacted the membrane fouling potential, which might be the result of changes of NOM characteristics. The transmembrane pressure (TMP) increased slightly and slowly with increasing dosage. The membrane fouled by preoxidation water was more amenable to chlorine‐induced permeability recovery, but it was contrary for hydraulically irreversible fouling. Therefore, preoxidation is a promising pret...

Food waste‐recycling (FWR) wastewater was evaluated as feedstock for two‐stage anaerobic digestion at different hydraulic retention times (HRTs). The FWR wastewater tested contained high concentrations of organic materials and had chemical oxygen demand (COD) >130 g/L and volatile solids (VS) >55 g/L. Two identical two‐stage anaerobic digesters were operated to investigate the performance at six HRTs ranging from 10–25 days. In the acidogenic reactor, the total carbohydrate reduction efficiency and volatile fatty acid production dramatically decreased when acidogenic HRT was

In order to improve the efficiency and evaluate the feasibility of anaerobic digestion for treatment of soybean protein wastewater. The stability and performance of the Up‐Flow Anaerobic Sludge Blanket (UASB) process was investigated at different organic loading rates (OLRS) and hydraulic retention times over 200 days. When chemical oxygen demand (COD) reached maximum, the loading rate was adjusted in a small way and indicators such as VFA, pH and COD in effluent as well as gas production are observed. These experimental results clearly showed that, the most proper corresponding organic loading rate (OLR) and hydraulic retention time were 6 kg/ (m3⋅d) (COD = 6000 mg/L) and 24 h respectively. Up to 85% of COD was removed and the CH4 production rate of 3.2 m3/(m3⋅d) was obtained. The produced biogas contained 72% of CH4. In the mean time, anaerobic sludge multiplies more faster and exiguous particles appeared. Granules with diameter 1–3 mm.

The production of a high efficiency microbial flocculant (MBF) by Proteus mirabilis TJ‐1 using compound organic wastewater was investigated. To cut down the cost of the MBF production, several nutritive organic wastewaters were selected to replace glucose and peptone as the carbon source and the nitrogen source in the optimized medium of strain TJ‐1, respectively. The compound wastewater of the milk candy and the soybean milk was found to be good carbon source and nitrogen source for this strain to produce MBF. The cost‐effective culture medium consists of (per liter): 800 mL wastewater of milk candy, 200 mL wastewater of soybean milk, 0.3 g MgSO4⋅7 H2O, 5 g K2HPO4, 2 g and KH2PO4, pH 7.0. The economic cost for the MBF production can be cut down over a half by using the developed culture medium. Furthermore, the utilization of the two wastewaters in the preparation of culture medium of strain TJ‐1 can not only save their big treatment cost, but also realize their resource reuse.

A study of bio‐hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 5.4 L). The continuous stirred tank reactor (CSTR) for bio‐hydrogen production was operated under the organic loading rates (OLR) of 8–32 kg COD/m3 reactor/d (COD: chemical oxygen demand) with molasses as the substrate. The maximum hydrogen production yield of 8.19 L/d was obtained in the reactor with the OLR increased from 8 kg COD/m3 reactor/d to 24 kg COD/m3 d. However, the hydrogen production and volatile fatty acids (VFAs) drastically decreased at an OLR of 32 kg COD/m3 reactor/d. Ethanoi, acetic, butyric and propionic were the main liquid fermentation products with the percentages of 31%, 24%, 20% and 18%, which formed the mixed‐type fermentation.A study of bio‐hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 5.4 L). The continuous stirred tank reactor (CSTR) for bio‐hydrogen production was operated under the organic loading rates (OLR) of 8–32 kg COD/m3 reactor/d (COD: chemical oxygen demand) with molasses as the substrate. The maximum hydrogen production yield of 8.19 L/d was obtained in the reactor with the OLR increased from 8 kg COD/m3 reactor/d to 24 kg COD/m3 d. However, the hydrogen production and volatile fatty acids (VFAs) drastically decreased at an OLR of 32 kg COD/m3 reactor/d. Ethanoi, acetic, butyric and propionic were the main liquid fermentation products with the percentages of 31%, 24%, 20% and 18%, which formed the mixed‐type fermentation.

In this study, a membrane aeration/filtration combined bioreactor (CMBR) was constructed, and the effect of alternate cycle by CMBR on membrane fouling and oxygen utilization efficiency (OUE) was investigated. Results showed that under the condition, when the alternate cycle was 0.75∼3h, the ΔTMP (TMP value of the time when a filtration cycle was over) of CMBR maintained a basically constant value during the 6 days’ continuous operation, which implied the CMBR achieved a favorable effect of the membrane fouling relieving. Too short or too long cycle would lead to a gradual increase of ΔTMP. OUE of CMBR increased with the extension of the alternate cycle. Thus, it suggested that the optimal alternate cycle of CMBR should be 3h.

A combined MBR (cMBR) with granular activated carbon (GAC) was used as a backbone system to treat the synthetic lineal alkylbenzene sulphonates (LAS) wastewater. The GAC was added in the MBR to improve the resistance of membrane fouling. A parallel conventional MBR (pMBR) without the GAC was run to give a contrast. The results of the process demonstrate that the cMBR process was more efficient than pMBR. It was found that the TMP changes of the cMBR were slower than the pMBR. The results demonstrated that the cMBRs membrane was better than the pMBR’s after a clean period run. It was the GAC scrubbing to the membrane that delayed the membrane fouling of the cMBR. Variable critical flux was found in MBR, which showed that the cMBR could make the critical flux better than pMBR in the run time, but GAC could not improve the critical flux at the end of the period for the severe membrane fouling. Based on this theory, a variable critical flux (J) of MBR was put forward, and the relationship of J with time (t) w...

In order to discuss the ability of H2‐production and wastewater treatment, an up‐flow anaerobic sludge bed (UASB) using a synthesized substrate with brown sugar wastewater was conducted to investigate the hydrogen yield, hydrogen producing rate, fermentation type of biohydrogen production, and the chemical oxygen demand (COD) removal rate, respectively. The results show that when the biomass of inoculants was 22.5 g SS⋅L−1 and the influent concentration, hydraulic retention time (HRT) and initial pH were within the ranges of 4000∼6000 mg COD⋅L−1, 8 h and 5–5.5, respectively, and the biohydrogen producing reactor could work effectively. The maximum hydrogen production rate is 5.98 L⋅d−1. Simultaneously, the concentration of ethanol and acetic acid is around 80% of the aqueous terminal production in the system, which presents the typical ethanol type fermentation. pH is at the range of 4∼4.5 during the whole performing process, however, the removal rate of COD is just about 20%. Therefore, it’s still needs ...

Aerobic granulation technology has become a novel biotechnology for wastewater treatment. However, the study of distinct properties and characteristics of phosphorus removal between granules and flocculent sludge are still sparse in EBPR. Two SBRs were concurrently operated to investigate the different phosphorus removal characteristics between granules (R1) and flocculate sludge (R2). Results indicated that R2 had a faster progress for enriching phosphorus‐accumulating organisms compared with R1, and the phosphorus removal reached the steady state after 40 days in R1 but only 30 days in R2. The moisture content of granules (85.63%) was smaller than that (91.36%) in R2, and the granules had a higher removal efficiency of NH4+‐N. However, flocculent sludge could release and take up more phosphorus. The special phosphorus release rate (SPRR) and special phosphorus uptake rate (SPUR) were 8.818 mg/gVSS⋅h and 9.921 mg/gVSS⋅h in R2 which were consistently larger than that (0.999 mg/gVSS⋅h and 0.754 mg/gVSS⋅h) ...

Neutralizing pH value of sugar cane juice is the important craft in the control process in the clarifying process of sugar cane juice, which is the important factor to influence output and the quality of white sugar. On the one hand, it is an important content to control the neutralized pH value within a required range, which has the vital significance for acquiring high quality purified juice, reducing energy consumption and raising sucrose recovery. On the other hand, it is a complicated physical‐chemistry process, which has the characteristics of strong non‐linearity, time‐varying, large time‐delay, and multi‐input. Therefore, there has not been a very good solution to control the neutralized pH value. Firstly, in this chapter, a neural network model for the clarifying process of sugar juice is established based on gathering 1200 groups of real‐time sample data in a sugar factory. Then, the HDP (Heuristic Dynamic Programming) method is used to optimize and control the neutralized pH value in the clarifying process of sugar juice. Simulation results indicate that this method has good control effect. This will build a good foundation for stabilizing the clarifying process and enhancing the quality of the purified juice and lastly enhancing the quality of white sugar.

This research aim to analysis bioethanol purification process. Bioethanol from cassava has been produced in previous research and the ethanol from molasses was taken from Bekonang region. The production of bioethanol from cassava was carried out through several processes such as homogenization, adding of α‐amylase, β‐amylase and yeast (Saccharomyces c). Two types of laboratory scale distillator have been used, the first type is 50 cm length and 4 cm diameter. The second type distillator is 30 cm length and 9 cm diameter. Both types have been used to distill bioethanol The initial concentration after the fermentation process is 15% for bioethanol from cassava and 20–30% ethanol from molasses. The results of first type distillator are 90% of bioethanol at 50° C and yield 2.5%; 70% of bioethanol at 60° C and yield 11.2%. 32% of bioethanol at 70° C and yield 42%. Meanwhile the second distillator results are 84% of bioethanol at 50° C with yield 12%; 51% of bioethanol at 60° C with yield 35.5%; 20% of bioethanol at 70° C with yield 78.8%; 16% of bioethanol at 80° C with yield 81.6%. The ethanol from molasses has been distillated once times in Bekonang after the fermentation process, the yield was about 20%. In this research first type distillator and the initial concentration is 20% has been used. The results are 95% of bioethanol at 75° C with yield 8%; 94% of bioethanol at 85° C with yield 13% when vacuum pump was used. And 94% of bioethanol at 90° C with yield 3.7% and 94% of bioethanol at 96° C with yield 10.27% without vacuum pump. The bioethanol purification use second type distillator more effective than first type distillator.

The kind of seed microorganisms and its growth conditions are important factors for the hydrogen fermentation. However, there are many kinds of bacteria in food waste, and it is necessary to know their behavior if it is used as a substrate. Therefore, hydrogen fermentation of food waste was investigated in the absence of inocula with an initial pH varying from 5 to 9 and in a temperature range between 22 to 50 °C. Hydrogen production occurred when the initial pH of the solution containing the food waste was adjusted to 7–9 and the temperature was adjusted to 22 or 35 °C (maximum production was 40 ml‐H2/g‐TS at an initial pH of 9 and a temperature of 35 °C). However, the hydrogen production stopped when the pH decreased due to the accumulation of organic acids. In the next step, the pH was controlled by the addition of a NaOH solution between 5.0 and 9.0. When the pH was controlled between 5.0–6.0, the hydrogen production increased to a maximum of 90 ml‐H2/g‐TS at a pH of 5.5 and a temperature of 35 °C; mo...

The effect of alkaline hydrothermal pre‐treatment for anaerobic digestion of mechanically‐sorted municipal solid waste (MSW) and source‐sorted waste was studied. Waste was hydrothermally pre‐treated in dilute alkali solution. Hydrolysis product was incubated in 500 ml saline bottle to determine methane potential (MP) under mesospheric anaerobic conditions. Optimum reaction condition obtained in the study is 170 °C at the dose of 4 g NaOH/100 g solid for one hour. Soluble COD was 13936 mg/L and methane yield was 164 ml/g VS for 6 days incubation at optimum conditions. More than 50% biogas increase was achieved over the control, and methane conversion ratio on carbon basis was enhanced to 30.6%. The digestion period was less than 6 days when pre‐treatment temperature was above 130 °C. The organic part of sorted waste is mainly constituted of kitchen garbage and leaf. Model kitchen garbage was completely liquidized at 130 °C for one hour and the methane yield was 276 ml/g VS. Addition of alkali enhance hydroxylation rate and methane yield slightly. The biogas potential of leaf could be observed by pre‐treatment above 150 °C under alkaline condition.

This article focuses on the effects of microwave thermal hydrolysis on sewage sludge anaerobic digestion. Volatile suspended solid (VSS) and COD solubilization of treated sludge were investigated. It was found that the microwave hydrolysis provided a rapid and efficient process to release organics from sludge. The increase of organic dissolution ratio was not obvious when holding time was over 5 min. The effect of the VSS solubilization was mainly dependent on temperature. The highest value of VSS dissolving ratio, 36.4%, was obtained at 170 °C for 30 min. COD dissolving ratio was about 25% at 170 °C. BMP test of excess sludge and mixture of primary and excess sludge proved the increase of methane production. Total biogas production of microwave treated mixture sludge increased by 12.9% to 20.2% over control after 30 days digestion. For excess sludge, biogas production was 11.1% to 25.9% higher than untreated sludge.

The method of preparing carbon nanotube (CNT) by milling of graphite particles in water followed by high temperature annealing is proposed and the mechanism discussed. Transmission electron microscopy (TEM) and X‐ray diffraction (XRD) line broadening analysis reveal that cleavage of the graphite particles occurs preferentially along the out‐of‐plane π bonds. Carbon K‐edge near edge X‐ray absorption fine structure (NEXAFS) of the milled graphite shows an increased sp3 character of the C=C bonds, but no major bonds rupture in the graphene sheets. The annealing at 1400 °C for 4 h of the milled graphite in argon results in formation of multiwalled carbon nanotubes accompanied with a number of coiled and twisted stacks of graphene sheets. The increased structural disorder of the milled graphite and presence of iron contaminations facilitate the rolling up of the cleaved graphene sheets during annealing.

Comparative results obtained for potable and waste water treatment with electrolytes and combined treatment with electrolytes and polyelectrolytes obtained by radiation technologies are presented. These polyelectrolyte mixtures have the capability to provide measurable improvements in potable water quality, especially leading to a considerable decrease of the “turbidity” (T < 1 NTU), “organic matters” (OM

As one of main biomass wastes in Japan, Sugi (Japanese cedar) leaves were chipped and treated for preparation of charcoal at mild temperature (250 – 450 °C) using superheated steam with controllable pressure. After the treatment, the solid residual charcoal was examined by FT‐IR and CHN elemental analysis. The results suggest that degree of carbonization was significantly affected by treating temperature, time and partial pressure of steam. A temperature above 400 °C and a partial pressure of steam above 4 MPa are necessary for accelerating and completing the carbonization within 2 hours. Adsorption experimental results of charcoal show that the residual charcoal has an excellent absorbability for ammonia gas and heavy metal ion Pb2+. Therefore it is expectable to develop mild superheated steam as reaction medium for preparing valuable charcoal products from biomass wastes with lower energy cost.

Identification of juvenile wood in green lumber following sawing would allow for segregation of juvenile wood from mature wood and application of special drying procedures to reduce warp. A dielectric means to detect juvenile wood by analysis of the real and imaginary signal components was applied via adjacent electrodes. Juvenile wood was successfully differentiated from normal wood by comparison of the imaginary signal component.

This short paper is devoted to analytical description of some radiative and collisional characteristics of multicharge ions: photoionization, excitation and ionization by electrons and ions. The corresponding formulas were obtained using accurate calculations and model potentials. The data presented can be used for solving plasma kinetic problems.

In the noiseless context, it has long been known that the average encoded word length of an instantaneous or uniquely decipherable code can be made to lie between the source entropy and that value plus unity. We address the question of finding sufficient conditions on the code–word probabilities for it to be possible to make the average code–word length approximate the entropy by a smaller prescribed amount.

The quantity of polymetric materials in the form of plastics, synthetic fibers and rubber derived from petrochemicals produced in the U.S. in 1974 amounted to about 18 million tons. This is modest compared to the approximately 50 million tons of wood pulp consisting essentially of cellulose produced, and in fact all our polymer needs could be met by conversion of the cellulose and lignin of wood. Cellulose can be hydrolyzed to glucose which can then be fermented to ethanol. The production of ethanol and its dehydration to ethylene, the most important petrochemical building block, proceed in high yield. However, the hydrolysis of cellulose whether by enzymes or by acid gives poor yields of glucose. Quantitative conversion of cellulose to glucose would improve the economics markedly. The high crystalline structure of cellulose limits access of the hydrolyzing agents except under conditions of acidity and temperature under which the glucose formed is destroyed. Futhermore the presence lignin prevents access of hydrolytic enzymes to the cellulose. Disruption of the cellulose crystal lattice by radiation or swelling agents has provided increased accessibility and higher glucose yields. Increasing the surface area of exposed cellulose by ball milling lignified cellulose has allowed enhanced enzymatic hydrolysis. However, more efficient techniques for removing these barriers to cellulose hydrolysis are needed.