Abstract: Green mussels (Perna viridis) can effectively remove
nutrients from seawater through their filtration process. This study
aims to estimate “net” nutrient removal rate by green mussel through
calculation of nutrient uptake and release. Nutrients (carbon, nitrogen
and phosphorus) uptake was calculated based on the mussel filtration
rate. Nutrient release was evaluated from carbon, nitrogen and
phosphorus released as mussel faeces. By subtracting nutrient release
from nutrient uptake, net nutrient removal by green mussel can be
found as 3302, 380 and 124 mg/year/indv. Mass balance model was
employed to simulate nutrient removal in actual green mussel
farming conditions. Mussels farm area, seawater flow rate, and
amount of mussels were considered in the model. Results show that
although larger quantity of green mussel farms lead to higher nutrient
removal rate, the maximum green mussel cultivation should be taken
into consideration as nutrients released through mussel excretion can
strongly affect marine ecosystem.
Abstract: Thermochemical conversion of non-edible biomass offers an efficient and economically process to provide valuable fuels and prepare chemicals derived from biomass in the context of developing countries. Pyrolysis has advantages over other thermochemical conversion techniques because it can convert biomass directly into solid, liquid and gaseous products by thermal decomposition of biomass in the absence of oxygen. The present paper aims to focus on the slow thermochemical conversion processes for non-edible Jatropha curcus seed cake. The present discussion focuses on the effect of nitrogen gas flow rate on products composition (wt %). In addition, comparative analysis has been performed for different mesh size for product composition. Result shows that, slow pyrolysis experiments of Jatropha curcus seed cake in fixed bed reactor yield the bio-oil 18.42 wt % at a pyrolysis temperature of 500°C, particle size of -6+8 mesh number and nitrogen gas flow rate of 150 ml/min.
Abstract: Constructed and natural wetlands are being used extensively to treat different types of wastewater including the domestic one. Considerable removal efficiency has been achieved for a variety of pollutants like BOD, nitrogen and phosphorous in the wetlands. Wetland treatment appears to be the best choice for treatment or pre-treatment of wastewater because of the low maintenance cost and simplicity of operation. Wetlands are the natural exporters of organic carbon on account of decomposition of organic matter. The emergent plants like reeds, bulrushes and cattails are commonly used in constructed wetland for the treatment process providing surface for bacterial growth, filtration of solids, nutrient uptake and oxygenation to promote nitrification as well as denitrification. The present paper explored different scopes of organic matter (BOD), nitrogen and phosphorous removal from wastewater through wetlands. Emphasis is given to look into the soil chemistry for tracing the behavior of carbon, nitrogen and phosphorus in the wetland. Due consideration is also made to see the viability for upgrading the BOD, nitrogen and phosphorus removal efficiency through different classical modifications of wetland.
Abstract: Nitrogen saturation has become one of the serious issues in the field of forest environment. The watershed protection forests located in the downwind hinterland of Tokyo Metropolitan Area are believed to be facing nitrogen saturation. In this study, we carefully focus on the balance of nitrogen between load and runoff. Annual nitrogen load via atmospheric deposition was estimated to 461.1 t-N/year in the upper reaches of the Kanna River. Annual nitrogen runoff to the forested headwater stream of the Kanna River was determined to 184.9 t-N/year, corresponding to 40.1% of the total nitrogen load. Clear seasonal change in NO3-N concentration was still observed. Therefore, watershed protection forest of the Kanna River is most likely to be in Stage-1 on the status of nitrogen saturation.
Abstract: Monitoring is essential to assessing the effectiveness of air pollution control actions. The goal of the air quality information system is through monitoring, to keep authorities, major polluters and the public informed on the short and long-term changes in air quality, thereby helping to raise awareness. Mathematical models are the best tools available for the prediction of the air quality management. The main objective of the work was to apply a Model that predicts the concentration levels of different pollutants at any instant of time. In this study, distribution of air pollutants concentration such as nitrogen dioxides (NO2), sulphur dioxides (SO2) and total suspended particulates (TSP) of industries are determined by using Gaussian model. Besides that, the effect of wind speed and its direction on the pollutant concentration within the affected area were evaluated. In order to determine the efficiency and percentage of error in the modeling, validation process of data was done. Sampling of air quality was conducted in getting existing air quality around a factory and the concentrations of pollutants in a plume were inversely proportional to wind velocity. The resultant ground level concentrations were then compared to the quality standards to determine if there could be a negative impact on health. This study concludes that concentration of pollutants can be significantly predicted using Gaussian Model. The data base management is developed for the air data of Hubli-Dharwad region.
Abstract: In this research, the optimum conditions for the synthesis of activated carbon from biodiesel wastes such as palm shells (PS) and Jatropha curcas fruit shells (JS) by chemical activation method using potassium hydroxide (KOH) as an activating agent under nitrogen atmosphere were investigated. The effects of soaking in hydrofluoric acid (HF), impregnation ratio, activation temperature and activation time on adsorption capacity of methylene blue (MB) and iodine (I2) solution were examined. The results showed that HF-treated activated carbons exhibited higher adsorption capacities by eliminating ash residues, which might fill up the pores. In addition, the adsorption capacities of methylene blue and iodine solution were also significantly influenced by the types of raw materials, the activation temperature and the activation time. The highest adsorption capacity of methylene blue 257.07mg/g and iodine 847.58mg/g were obtained from Jatropha curcas wastes.
Abstract: Application of compost in agriculture is very desirable worldwide. In the Czech Republic, compost is the most often used to improve soil structure and increase the content of soil organic matter, but the effects of compost addition on the fate of mineral nitrogen are only scarcely described. This paper deals with possibility of using combined application of compost, mineral and organic fertilizers to reduce the leaching of mineral nitrogen from arable land. To demonstrate the effect of compost addition on leaching of mineral nitrogen, we performed the pot experiment. As a model crop, Lactuca sativa L. was used and cultivated for 35 days in climate chamber in thoroughly homogenized arable soil. Ten variants of the experiment were prepared; two control variants (pure arable soil and arable soil with added compost), four variants with different doses of mineral and organic fertilizers and four variants of the same doses of mineral and organic fertilizers with the addition of compos. The highest decrease of mineral nitrogen leaching was observed by the simultaneous applications of soluble humic substances and compost to soil samples, about 417% in comparison with the control variant. Application of these organic compounds also supported microbial activity and nitrogen immobilization documented by the highest soil respiration and by the highest value of the index of nitrogen availability. The production of plant biomass after this application was not the highest due to microbial competition for the nutrients in soil, but was 24% higher in comparison with the control variant. To support these promising results the experiment should be repeated in field conditions.
Abstract: The atomization effect is an important factor of the heat transfer of liquid nitrogen spray. In this paper, two kinds of internal-mixing twin-fluid atomizers were design. According to the fracture theory and fluid mechanics, the model is established to simulate atomization effect. The results showed that: Internal-mixing atomizers, with the liquid nitrogen atomization size from 20um to 40um, have superior performance. Y-jet atomizer spray speed is greater than Multi-jet atomizer, and it can improve the efficiency of heat transfer between the liquid nitrogen and its spray object. Multi-jet atomizer atomization cone angle is about 30°, Y-jet atomizer atomization cone angle is about 20°. During atomizer selection, the size of the heat transfer area should be considered.
Abstract: Activated carbons were produced from olive stones by a chemical process. The activated carbon (AC) were modified by nitric acid and used as adsorbents for the removal of methylene blue dye from aqueous solution. The activated carbons were characterized by nitrogen adsorption and enthalpy of immersion. Batch adsorption experiments were carried out to study the effect of initial different concentrations solution on dye adsorption properties. Isotherms were fitted to Langmuir model, and corresponding parameters were determined. The results showed that the increase of ration of ZnCl2 leads to increase in apparent surface areas and produces activated carbons with pore structure more developed. However, the maximum MB uptakes for all carbons were determined and correlated with activated carbons characteristics.
Abstract: This work assessed some properties of three pedons on a toposequence in Ijah-Gbagyi district in Niger State, Nigeria. The pedons were designated as JG1, JG2 and JG3 representing the upper, middle and lower slopes respectively. The surface soil was characterized by dark yellowish brown (10YR3/4) color at the JG1 and JG2 and very dark grayish brown (10YR3/2) color at JG3. Sand dominated the mineral fraction and its content in the surface horizon decreased down the slope, whereas silt content increased down the slope due to sorting by geological and pedogenic processes. Although organic carbon (OC), total nitrogen (TN) and available phosphorus (P) were rated high, TN and available P decreased down the slope. High cation exchange capacity (CEC) was an indication that the soils have high potential for plant nutrients retention. The pedons were classified as Typic Haplustepts/ Haplic Cambisols (Eutric), Plinthic Petraquepts/ Petric Plinthosols (Abruptic) and Typic Endoaquepts/ Endogleyic Cambisols (Endoclayic).
Abstract: According to biodiesel from microalgae is an attractive fuel for several reasons such as renewable, biodegradable and environmental friendly. Thus, this study, green microalgae Scenedesmus acutus PPNK1 isolated from natural water, was selected based on high growth rates, easy cultivation and high lipid content. The Nile red fluorescence method has been successfully applied to the determination of lipids in S. acutus PPNK1. The combination of the method to the lipid composition in algal cells showed the yellow fluorescence under fluorescent microscope. Interestingly, maximum cell numbers and biomass concentration were obtained at 5.44´107 cells/mL and 1.60 g/L when it was cultivated in BG-11 medium while in case of BG-11 with nitrogen deprivation (N 0.25 g/L), accumulated lipid content in cells (44.67%) was achieved that was higher than that found in case of BG-11 medium at about 2 times (22.63%).
Abstract: In order to Study the efficacy application of green
manure as chickpea pre plant, field experiments were carried out in
2007 and 2008 growing seasons. In this research the effects of
different strategies for soil fertilization were investigated on grain
yield and yield component, minerals, organic compounds and
cooking time of chickpea. Experimental units were arranged in splitsplit
plots based on randomized complete blocks with three
replications. Main plots consisted of (G1): establishing a mixed
vegetation of Vicia panunica and Hordeum vulgare and (G2):
control, as green manure levels. Also, five strategies for obtaining the
base fertilizer requirement including (N1): 20 t.ha-1 farmyard manure;
(N2): 10 t.ha-1 compost; (N3): 75 kg.ha-1 triple super phosphate;
(N4): 10 t.ha-1 farmyard manure + 5 t.ha-1 compost and (N5): 10 t.ha-1
farmyard manure + 5 t.ha-1 compost + 50 kg.ha-1 triple super
phosphate were considered in sub plots. Furthermoree four levels of
biofertilizers consisted of (B1): Bacillus lentus + Pseudomonas
putida; (B2): Trichoderma harzianum; (B3): Bacillus lentus +
Pseudomonas putida + Trichoderma harzianum; and (B4): control
(without biofertilizers) were arranged in sub-sub plots. Results
showed that integrating biofertilizers (B3) and green manure (G1)
produced the highest grain yield. The highest amounts of yield were
obtained in G1×N5 interaction. Comparison of all 2-way and 3-way
interactions showed that G1N5B3 was determined as the superior
treatment. Significant increasing of N, P2O5, K2O, Fe and Mg content
in leaves and grains emphasized on superiority of mentioned
treatment because each one of these nutrients has an approved role in
chlorophyll synthesis and photosynthesis abilities of the crops. The
combined application of compost, farmyard manure and chemical
phosphorus (N5) in addition to having the highest yield, had the best
grain quality due to high protein, starch and total sugar contents, low
crude fiber and reduced cooking time.
Abstract: Calcium oxide (CaO) as carbon dioxide (CO2)
adsorbent at the elevated temperature has been very well-received
thus far. The CaO can be synthesized from natural calcium carbonate
(CaCO3) sources through the reversible calcination-carbonation
process. In the study, cockle shell has been selected as CaO
precursors. The objectives of the study are to investigate the
performance of calcination and carbonation with respect to different
temperature, heating rate, particle size and the duration time. Overall,
better performance is shown at the calcination temperature of 850oC
for 40 minutes, heating rate of 20oC/min, particle size of < 0.125mm
and the carbonation temperature is at 650oC. The synthesized
materials have been characterized by nitrogen physisorption and
surface morphology analysis. The effectiveness of the synthesized
cockle shell in capturing CO2 (0.72 kg CO2/kg adsorbent) which is
comparable to the commercialized adsorbent (0.60 kg CO2/kg
adsorbent) makes them as the most promising materials for CO2
capture.
Abstract: The objective of this work was to examine the
changes in the microstructure and macro physical properties caused
by the carbonation of normalised CEM II mortar. Samples were
prepared and subjected to accelerated carbonation at 20°C, 65%
relative humidity and 20% CO2 concentration. On the microstructure
scale, the evolutions of the cumulative pore volume, pore size
distribution, and specific surface area during carbonation were
calculated from the adsorption desorption isotherms of nitrogen. We
also examined the evolution of macro physical properties such as the
porosity accessible to water, the gas permeability, and thermal
conductivity. The conflict between the results of nitrogen porosity
and water porosity indicated that the porous domains explored using
these two techniques are different and help to complementarily
evaluate the effects of carbonation. This is a multi-scale study where
results on microstructural changes can help to explain the evolution
of macro physical properties.
Abstract: The equilibrium process of plasma nitrogen species by
chemical kinetic reactions along various pressures is successfully
investigated. The equilibrium process is required in industrial
application to obtain the stable condition when heating up the
material for having homogenous reaction. Nitrogen species densities
is modeled by a continuity equation and extended Arrhenius form.
These equations are used to integrate the change of density over the
time. The integration is to acquire density and the reaction rate of
each reaction where temperature and time dependence are imposed.
A comparison is made with global model within pressure range of 1-
100mTorr and the temperature of electron is set to be higher than
other nitrogen species. The results shows that the chemical kinetic
model only agrees for high pressure because of no power imposed;
while the global model considers the external power along the
pressure range then the electron and nitrogen species give highly
quantity densities by factor of 3 to 5.
Abstract: Electrical discharge machining (EDM) is well
established machining technique mainly used to machine complex
geometries on difficult-to-machine materials and high strength
temperature resistant alloys. In the present research, the objective is
to study the shape of the electrode and establish the application of
liquid nitrogen in reducing distortion of the electrode during
electrical discharge machining of M2 grade high speed steel using
copper electrodes. Study of roundness was performed on the
electrode to observe the shape of the electrode for both conventional
EDM and EDM with cryogenically cooled electrode. Scanning
Electron Microscope (SEM) has been used to study the shape of
electrode tip. The effect of various parameters such as discharge
current and pulse on time has been studied to understand the behavior
of distortion of electrode. It has been concluded that the shape
retention is better in case of liquid nitrogen cooled electrode.
Abstract: Novel nitrogen removal technologies via nitrite
pathway attract increasing interest in recent years. In this study,
batch experiments were performed to investigate nitrite accumulation
characteristics and shifts in nitrifying community structure at
different growth environments including ammonia concentration, pH
and alkalinity. It was found that nitrite accumulation ratios were
maintained at around 95% at studied conditions, and the optimum pH
and Alk/N (ratio between alkalinity and nitrogen) for ammonium
oxidization were 8.5 and 8.33, respectively. Fluorescence in situ
hybridization analysis of nitrifying bacteria showed that high free
ammonia (from influent ammonium or caused by high pH)
significantly altered the structure of nitrifying community, leading to
abundance of ammonia-oxidizing bacteria (AOB), especially
Nitrososmonas, and inhibition of nitrite-oxidizing bacteria (NOB).
The results suggest that free ammonia plays more important role than
other studied conditions on nitrite accumulation.
Abstract: Cattle manure and mineral fertilizers are two source
of Nitrogen, which can affect the growth and quantity of potato. In
this research the effects of the use of cattle manure (5, 10, 15 and 20
ton ha-1), Nitrogen fertilizer (50, 100 and 150 kg N ha-1) and their
interaction on potato growth were evaluated during field
experiments in 2008 with the help of Randomized Complete Block
(RCB) with the factorial arrangement of three experimental
replications in Iran. At the 75 th day after emergence, dry weight of
Shoots, leaf area index (LAI) and plant height were recorded. Results
showed that, dry weight of Shoots, LAI and plant height increased
linearly and very significantly in response to the application of
manure and Nitrogen fertilizer. While the interaction between
manure and Nitrogen fertilizer just on the LAI and plant height was
significant, somehow the maximum amount of plant height( 73 cm)
was obtained by using 150 kg Nitrogen + 15 tons of manure per
hectare, and maximum LAI ( 5.36) was obtained by using 150 kg
Nitrogen + 20 tons of manure per hectare. Also in this experiment
maximum tuber yield (36.8 tons ha-1) was obtained by the utilization
of 150 kg Nitrogen per hectare + 20 tons manure.
Abstract: Strain M was isolated from the latex of Hevea brasiliensis that grow in the rubber farm area of Malaysia Rubber Board. Strain M was tentatively identified as Bacillus sp. Strain M demonstrated high protease production at pH 9, and this was suitable to be applied in rubber processing that was in alkaline conditions. The right and suitable proportion to be used in applying supernatant into the latex was two parts of latex and one part of enzyme. In this proportion, the latex was stable throughout the 72 hours of treatment. The potential of strain M to degrade protein in the natural rubber latex was proven with the reduction of 79.3% nitrogen in 24 hours treatment. Centrifugation process of the latex before undergoing the treatment had increased the protein degradation in latex. Although the centrifugation process did not achieve zero nitrogen content, it had improved the performance of protein denaturing in the natural rubber.
Abstract: The present study describes the biosynthesis of a milkclotting
protease by solid state fermentation (SSF) of a locally
isolated mould, Rhizopus stolonifer. The production medium was
prepared using wheat bran at 50% (w/v). The production conditions
are optimized by varying 7 parameters: carbon and nitrogen sources,
medium moisture, temperature, pH, fermentation time and
inoculum-s size. The maximum enzyme synthesis was measured after
96 h of incubation time at temperature of 28°C. The optimum pH
determined was 6 and the inoculum size was 3.106spores/ml. The
optimum initial moisture content is comprised between 50 to 70%.
The formation of milk clotting protease is enhanced when galactose
and peptone are used at 10% (w/v) and 1% (w/v) concentrations
respectively. The maximum production of milk clotting protease is
120 US/ml.