Drought by climate change in East Mediterranean Region will change soil temperature and moisture that lead to alter the cycling of biological elements like carbon and nitrogen. However, there are few studies that show how sensitivity of soil organic matter mineralization to temperature and/or moisture can be modified by changes in these parameters. In order to study how these changes in temperature and moisture affect soil carbon and nitrogen mineralization, a laboratory experiment was carried out in two depths (0-5 and 5-15 cm) of soils of Onobrychis beata and Trifolium speciosum being common annual plants in Turkey that was taken from Kızıldag Plataeu (Adana city). Some soil physical and chemical properties and as well as rate of carbon and nitrogen mineralizations were determined for both depths of soils. These soils were incubated for 42 days under different field capacities (FC 60, 80 and 100%) and temperatures (24, 28 and 32°C). Cumulative carbon mineralization (Cm), potential mineralizable carbon (C0) and rate of carbon mineralization of all soils were increased with rising temperatures. Rate of carbon mineralization in O. beata soil were lower than T. speciosum soil. NH4-N and NO3-N contents at 42nd day were higher than initial levels of soils and also increased with temperatures and field capacities. In summary, sensitivity of soil organic matter mineralization to temperature was higher at 32°C in upper layer and lower at 24°C in deeper layer of both soils.
Laser cutting is a non-traditional cutting process and cutting of square blank in stainless steel-304 sheets cause heat affected zone (HAZ) and thermal stress. Formation of HAZ is undesirable and excessive stress cause surface defects. Thus, it is necessary to analyze them intensively. The process of laser cutting is a complex thermo-mechanical process. Hence, in this study a thermo-mechanical finite element model has been introduced by ANSYS to predict the temporal variation together with thermal stress and width of heat affected zone (HAZ). CO2 laser is used to cut 10 × 10 mm square blank in a 3 mm thick stainless steel-304 sheet. Optical microscope and SEM are used to analyse the parametric effect on surface quality at the cutting edge. The results showed that maximum temperature at the cutting edge is about to melting temperature and independent to laser power and cutting speed. Importantly, cutting speed has significant effect on rate of temperature variation. Moreover, the width of HAZ increases with the increase of laser power and decrease of cutting speed. However results of ANOVA suggested that laser power is the most significant parameter having 64.21% of contribution to width of HAZ. Furthermore, maximum stress is observed at the corner; which is supported by SEM analysis.
The mechanical properties of Dual Phase Steel (DPS)-duplex structure-produced by quenching in pre-heated bitumen have been investigated. Medium carbon steels intercritically heated at different temperatures and holding times were quenched in hot bitumen. Optical and scanning electron microscopy characterisation of the duplex structure showed extensive network of fibrous martensite in a ferritic matrix with occasional presence of polygonal martensite. The duplex phase structure exhibited continuous yielding dynamics, improving the tensile and hardness values by about 42 and 35%, respectively, relative to the normalised structure. But, the elongation and impact values decreased by about 42 and 50%, respectively, when compared to the normalised structure. These values are similar to those obtained in duplex structure produced using conventional oil quenching. The tensile fractured surface showed transition between a predominantly cleavage mode in the lower annealing temperature to a mixed mode in the upper bound of the annealing temperature. These findings suggest that pre-heated bitumen can be exploited for the production of DPSs.
In the last few decades, surfactants and electrolyte interaction has gained considerable attention of researchers due to their industrial and domestic applications. In this work, the effects of electrolyte (NaCl) on the critical micelle concentration (CMC) of the cationic surfactant cetyltrymethyl ammonium bromide (CTAB) at different temperatures were investigated through different techniques such as conductometry, surface tensiometer and viscosimeter. The results showed that the values of CMC of CTAB decreased with the increase in temperature as well as with the addition of NaCl. The value of CMC for pure CTAB was calculated 0.98M at 303K, which was observed to decrease as temperature increased and got value of 0.95M at 318K. Moreover the addition of electrolyte NaCl into the surfactant lead to lowering of the CMC and obtained value of 0.90M at 3M of NaCl, indicating significant electrostatic interactions between surfactant and electrolyte. Moreover the degree of ionization(α) calculated for pure cationic surfactant CTAB was 0.219, which tends to increase with the addition of electrolyte, while that of counter ion binding values (β) was observed to decrease from 0.780 to 0.201. Furthermore, the conductivity of charged micelle of surfactant and free ions of electrolyte contributed to electric conductivity of aqueous micellar solution of surfactant. The results can be helpful to develop better understanding about interaction between electrolyte and surfactant.
A series of monoamide isomers have been successfully synthesised and characterised using combination of common spectroscopic techniques such Fourier Transform Infrared (FT-IR), 1H and 13C Nuclear Magnetic Resonance (NMR) and Ultraviolet-visible (UV-vis). The monoamide compounds namely 6-(3-methyl-pyridin-2-ylcarbamoyl)-pyridine2-carboxylic acid methyl ester (L1), 6-(4-methyl-pyridin-2-ylcarbamoyl)-pyridine-2-carboxylic acid methyl ester (L2), 6-(5-methyl-pyridin-2-ylcarbamoyl)-pyridine-2-carboxylic acid methyl ester (L3) and 6-(6-methyl-pyridin-2ylcarbamoyl)-pyridine-2-carboxylic acid methyl ester (L4) were prepared from reaction between 6-(methoxycarbonyl) pyridine-2-carboxylic acid with 2-amino-N-methylpyridine (where N = 3, 4, 5 and 6) by using acyl chloride reaction. In this present studies, the synthesis and characterization of these compounds are discussed along with the inductive effects contributed by methyl substituted groups at the pyridine ring.
This study examined the influence of pH and salt concentration on the protein solubility of slaughtered and non-slaughtered broiler chicken meat. Three types of salt (NaCl, Na2SO4, and (NH4)2SO4), five different pH levels (5.0, 6.0, 7.0, 8.0 and 9.0) and five salt concentrations (0.4, 0.8, 1.2, 1.6, and 2.0 M) were examined. Each type of salt showed distinctive activities for slaughtered and non-slaughtered meat protein solubility. Soluble protein concentration increased as pH increased (p<0.05) from pH5.0 to 8.0 and decreased from pH8.0 to 9.0. It was also observed that protein solubility increased as the salt concentration increased. Protein solubility significantly increased (p<0.05) in the non-slaughtered meat compared to the slaughtered meat at pH8.0 for Na2SO4 at 1.2 M.
β-Glucan, the representative dietary fibre component of barley, has received much attention, primarily due to its nutritional significance. In this study, β-glucans prepared from barley pearling byproducts were characterized with respect to their molecular weight, solubility and viscosity. Following the initial alkaline extraction, the crude β-glucan extract (45% purity) was further purified to approximately 90%. The isolated β-glucans exhibited a wide molecular weight range with peak molecular weight of less than 1 × 106 daltons. Solubilities of crude and purified β-glucans in water were lower than that of β-glucan in the native barley pearling byproducts. However, the aqueous solubility of purified β-glucan from pearlings was substantially higher than that of commercial β-glucan. Compared to the latter, purified β-glucan exhibited low apparent viscosity in aqueous solutions.
Agrobacterium-mediated transformation of indica rice is undoubtedly a challenging task due to the rice recalcitrant nature to transformation process. Therefore, optimization of the transformation protocol is important for specific indica rice cultivar to ensure effectiveness of the transformation. In this study, crucial parameters affecting Agrobacteriummediated transformation were optimized to obtain transgenic rice of local rice cultivar (indica MR219). Embryogenic calli were chosen for inoculation with Agrobacterium tumefaciens strain LBA4404 harbouring a binary vector pH2GW7ABP57 containing gene of interest, Auxin binding protein 57 (Abp57). The parameters that have been optimized were the immersion time, co-cultivation period, acetosyringone concentration and co-cultivation temperature. A total of four days co-cultivation period and 30 min immersion of embryogenic callus are optimum for the transformation of MR219 with transformation efficiency of 26.4% and 16.0%, respectively. Acetosyringone at 200 μM and co-cultivation at 28°C also gave the highest transformation efficiency (14.4 and 18.4%, respectively). Meanwhile, inclusion of 20 g/L maltose+20 g/L sorbitol into the regeneration media has significantly improve the transformed somatic embryos growth and increase the regeneration efficiency up to 40.0%. The results of polymerase chain reaction (PCR) and reverse transcription-polymerase chain reaction (RT-PCR) indicated that the transgene was successfully integrated and overexpressed in transgenic rice of MR219. In conclusion, significant improvement in transformation efficiency for rice cv. MR219 has been obtained by using the optimised protocol for transformation and regeneration developed in this study.
Wild stocks of endangered mrigal carp, Cirrhinus cirrhosus (Bloch 1795), continues to decline rapidly in the Indo-Ganges river basin. With an objective to evaluate its population status, landmark-based morphometric and meristic variations among three different stocks viz., hatchery (Jessore), baor (Gopalganj) and river (Faridpur) in Bangladesh were studied. Significant differences were observed in 10 of the 15 morphometric measurements viz., head length, standard length, fork length, length of base of spinous, pre-orbital length, eye length, post-orbital length, length of upper jaw, height of pelvic fin and barbel length, two of the 8 meristic counts viz., scales above the lateral line and pectoral fin rays and 10 of the 22 truss network measurements viz., 1 to 10, 2 to 3, 2 to 8, 2 to 9, 2 to 10, 3 to 4, 3 to 8, 4 to 5, 4 to 7 and 9 to 10 among the stocks. For morphometric and landmark measurements, the 1st discriminant function (DF) accounted for 58.1% and the 2nd DF accounted for 41.9% of the among-group variability. In discriminant space, the river stock was isolated from the other two stocks. On the other hand, baor and hatchery stocks formed a very compact cluster. A dendrogram based on the hierarchical cluster analysis using morphometric and truss distance data placed the hatchery and baor in one cluster and the river in another cluster and the distance between the river and hatchery populations was the highest. Morphological differences among stocks are expected, because of their geographical isolation and their origin from different ancestors. The baseline information derived from the present study would be useful for genetic studies and in the assessment of environmental impacts on C. cirrhosus populations in Bangladesh.
Grain size spectrum and textural parameters for the fluvial sediment bed in seven tropical rivers of Kelantan, Malaysia are presented in this article. The samples were collected from six tributaries to the main Sungai Kelantan spanning approximately 248 km stretch of water streams. Sand or gravel dominated river was identified for each river using the sediment composition analysis. Textural pattern shows complicated profiles of mean size and no consistent decreasing grain size and gradation parameter were observed towards the downstream flow. Most of the samples fall under the category of either very poorly sorted or poorly sorted and has very platykurtic kurtosis distributions. CM diagram (C=one percentile in microns and M = median grain size in microns) suggested that the deposition of fine-grained sediment for samples with median grain size d50 <1 mm are either by rolling, rolling and saltation or saltation and suspension.
The uniaxial compressive strength test is a destructive and time consuming test. A number of non-destructive methods using portable testing equipment are more applicable and easier to conduct. This paper presents the results of a systematic approach to determine the uniaxial compressive strength of rock material using the Schmidt hammer rebound test. A total of five distinct locations (Graham Coast, Davis Coast, Nanson Island, Danco Coast and Trinity Island) were tested using the Schmidt rebound hammer test. Peninsula Antarctic located at northwest of Antarctic region comprising of igneous and metamorphic rocks. Statistical analysis of the results at 95% confidence level showed the Schmidt rebound value of the Graham Coast ranges from 40±1.7 to 41±1.3 with standard deviation of 8.2 to 6.4. The rebound value for Davis Coast was 39±1.6 with standard deviation of 7.7. Rocks from Nanson Island and Danco Coast have the Schmidt rebound value of 54±1.7 with standard deviation of 8.0 and 36±1.3 with standard deviation of 6.2, respectively. The Schmidt rebound value of rocks at Trinity Island ranges from 29±1.4 to 32±1.7 with standard deviation of 6.8 to 8.1. Thus, the respective uniaxial compressive strengths of rock materials from Graham Coast, Davis Coast, Danco Coast, Nanson Island and Trinity Island were 73-108, 50, 59, 164 and 45-59 MPa. The respective ISRM strength classification of rock materials of Graham Coast, Davis Coast, Danco Coast, Nanson Island and Trinity Island were strong (R4) to very strong rock (R5), medium strong rock (R3), strong rock (R4), very strong rock (R5) and medium strong (R3) to strong rock (R4). The results showed a mean of quantification of rock material strength based on the Schmidt Hammer rebound test in Antarctic Peninsula.
This paper addresses the optimal Dye Solar Cell (DSC) design considering parameters namely TiO2
thickness, surface
area, iodide concentration in electrolyte and TiO2
passivation layer thickness as they have influence on DSC performance.
It aims to do the research of the practical use of Taguchi method in the optimization of DSC design in order to improve
the performance of DSC. This work highlight on the integration of Taguchi method with simulation which showed that the
optimal design of DSC is 10 µm thickness of TiO2
, 90m2
/g of TiO2
photoelectrode surface area, 1 M iodide concentration
in electrolyte and two layers with 20 nm thickness of TiO2
passivation layer with efficiency of 4.59165%. All the features
of the Taguchi-based optimization were also discussed.
A series of Mg/TiO2
photocatalysts were prepared using aqueous wet impregnation method at different Mg loading
followed by calcination at different temperatures for 1 h duration. The photocatalysts were characterized using thermal
gravimetry, Fourier-transform infrared spectroscopy, x-ray diffraction, field emission scanning electron microscopy and
high-resolution transmission electron microscopy. The photocatalysts were investigated for photooxidative-extractive
deep desulfurization of model oil containing dibenzothiophene at room temperature and under visible light irradiation.
The model oil containing 100 ppm S was photooxidized followed by extraction using imidazolium-phosphate ionic liquids
at room temperature. The best performing photocatalyst was 0.25 wt. % Mg/TiO2
calcined at 400°C (0.25Mg400), in
which 98.4% of dibenzothiophene (3.070 mmol DBT per g photocatalyst) was converted to dibenzothiophene sulfone. The
highest extraction efficiency of 97.8% (0.01525 mmol S per mL ionic liquid) was displayed by 1,2-diethylimidazolium
diethylphosphate.
Liquid natural rubber (LNR) was functionalized into liquid epoxidized natural rubber (LENR) and hydroxylated LNR (LNROH)
via oxidation using a Na2
WO4
/CH3
COOH/H2
O2
catalytic system. Microstructures of LNR and functionalized LNRs
were characterized using Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies. The
effect of CH3
COOH, H2
O2
, Na2
WO4
, reaction time and temperature. reaction time and temperature on epoxy content were
investigated. LNR-OH was obtained when oxidation reaction was conducted at a longer reaction time, higher temperature
or excess amount of catalyst. Thermogravimetric analysis (TGA) reported the thermal behavior of functionalized LNRs.
Molecular weight and polydispersity index (PDI) were determined using gel permeation chromatography (GPC).
A suitable and cost-effective microfabrication technique for processing aluminum micropart is required, as the choice
of aluminum microparts for aerospace, electronics and automobile components is preferred over other metals due to its
excellent properties. Meanwhile, powder injection molding (PIM) is identified as an economical manufacturing technique
for processing ceramic and micro-metal powders into microparts and or components. Therefore, this study investigates
formulation and processing of aluminum PIM feedstock using a custom-made machine. The investigation is focused on
the effect of mixing process parameters (powder loading, rotor speed and mixing temperature) and the suitability of
the backbone polymer. The formulated PIM feedstock constituents are paraffin wax (PW), stearic acid (SA), high-density
polyethylene (HDPE)/ medium-density polyethylene (MDPE) alternatively and aluminum micro-metal powder. Taguchi
method is used for the design of experiments (DOEs) and analysis. In addition, response surface methodology (RSM) is
employed to develop empirical viscosity models. The optimum powder-binder mixing ratio of 58:42 vol. % with rotor
speed of 43 rpm were determined for preparing aluminum PIM feedstock using mini-lab mixer developed. The empirical
model developed for aluminum PIM feedstock viscosity shows a good fit with R2
values of 0.84 using HDPE and 0.96 for
MDPE binder system. This investigation demonstrates preparation and suitability of aluminum PIM feedstock using waxbased
binder system.
The Cox proportional hazards model is most widely used in survival analysis for modeling censored survival data. In
this model, the effect of the covariates is assumed to act multiplicatively on the baseline hazard rate and the ratio of the
hazards is constant over survival time. This is an important assumption and sometimes may not hold in some survival
studies. The Cox model can lead to biased results when the proportionality assumption is not satisfied. In such a situation,
the additive hazards regression models have been an alternative to proportional hazards models. The Aalen model
allows for time-varying covariate effects. In some situations, some covariate effects may be constant but the others may
not. In such cases, the Cox-Aalen model is a better alternative since it allows to combine both kinds of covariates in
the same model. In this study the Cox proportional hazards model, Aalen’s additive hazards model and the Cox-Aalen
model have been considered. These models have been applied to kidney transplant data and the differences in estimates
of the unknown parameters obtained by the Aalen’s model, the Cox model and the Cox-Aalen model are investigated.
Justicia gendarussa methanolic leaves extract from four different locations in Southern region of Malaysia and distribution
of two flavonoids, naringenin and kaempferol in plant organs (young and mature leaves) were determined using gas
chromatography-flame ionization detector (GC-FID) analysis. Naringenin and kaempferol contents were detected
and quantified in leaves extract. The results indicated that mature leaves contained more naringenin and kaempferol
compared to young leaves. The highest concentration of naringenin and kaempferol were recorded in mature leaves from
Skudai and Muar regions which were 507.692 and 1226.964 mgkg-1, respectively. Data analysis showed that naringenin
content was directly proportional to the amount of kaempferol in the leaf extracts. In conclusion, this study suggested
geographical variation among plant samples and physiological stage of organ parts could contribute to variation in
flavonoids concentration in a plant species.
In order to investigate the changes in meat quality characteristics and some serum metabolites as well as carcass yield,
non-carcass parts, internal organs of lambs as influenced by birth weight (BtW) and feeding system (FS), 28 Karayaka
male lambs (150 days of age) obtained from four comparable groups that consisted of seven replicates according to a 2 ×
2 factorial arrangement for 2 BtW (low, 4.1 ± 0.06 kg and high, 5.0 ± 0.09 kg) and 2 FS (total mixed ration, TMR and free
choice feeding, FCF) were used. After weaning (90 days of age), lambs with low BtW and high BtW were fed individually
a TMR ad libitum or fed on the same ingredients (FCF) as that of TMR. The TMR was consisted of 80% of a compound feed
and 20% of roughage based on a dry matter basis (140 g crude protein and 10.7 ME MJ/kg). The carcass weight and yield
of lambs were not affected by the BtW, FS and BtWxFS interaction. The slaughter body weight, cold carcass weight and
yield of FCF-fed lambs were higher than those of TMR-fed animals. The pH45 and shear force of semitendinosus muscle
decreased and increased by the FCF systems, respectively. These results showed that BtW of lambs did not affect the
studied parameter and that feeding system created more differences in terms of some parameters due to the fact that the
FCF lead to improvement in carcass and some meat quality traits.
Remote Sensing (RS) and Geographical Information Systems (GIS) are widely used for change detection in rivers caused
by erosion and accretion. Digital image processing techniques and GIS analysis capabilities are used for detecting
temporal variations of erosion and accretion characteristics between the years 1999 and 2011 in a 40 km long Marala
Alexandria reach of River Chenab. Landsat satellite images for the years 1999, 2007 and 2011 were processed to analyze
the river channel migration, changes in the river width and the rate of erosion and accretion. Analyses showed that the
right bank was under erosion in both time spans, however high rate of deposition is exhibited in middle reaches. The
maximum erosion was 1569843 m2
and 1486160 m2
along the right bank at a distance of 24-28 km downstream of the
Marala barrage in the time span of 1999-2007 and 2007-2011, respectively. Along right bank mainly there is trend of
accretion but erosion is much greater between 20 and 28 km reach. Maximum accretion was 5144584 m2
from 1999-2007
and 2950110 m2
from 2007-2011 on the right bank downstream of the Marala Barrage. The derived results of channel
migration were validated by comparing with SRTM data to assess the accuracy of image classification. Integration of remote
sensing data with GIS is efficient and economical technique to assess land losses and channel changes in large rivers.
This study was carried out to examine the water quality of Batang Rajang at Pelagus area, Sarawak, Malaysia. Water
quality was determined at 12 stations along Batang Rajang and its tributaries in terms of in-situ and ex-situ water
quality parameters. The results showed that most stations at main river were categorized as slightly polluted while
most tributaries were clean according to the Water Quality Index. The river is suffering from organic pollution where
almost all stations along the river contained high chemical oxygen demand (≈ 43.1 mg/L) and total ammonia nitrogen
(≈ 0.520 mg/L) and were classified as Class III and IV at most of the stations. High suspended solids (218.3 mg/L) and
low dissolved oxygen (4.6 mg/L) were observed at the main river. The low dissolved oxygen content from the Bakun
dam upstream of the study area has an impact on the river particularly during dry season where DO dropped below the
minimum required for sensitive aquatic organisms. As seven tributaries are within Class II indicating healthy freshwater
ecosystems, they should be conserved as habitats for sensitive aquatic organisms. Conversely, proper management need
to be initiated in particular, Sungai Merit tributary and the main river where DO were below the minimum required for
sensitive aquatic organisms.