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A novel and selective method for the fast determination of trace amounts of Co(II)ions in water samples has been developed.  The first organic-solution-processable functionalized-Multiwalled carbon nanotubes (MWNTs) (SPFMWNTs) hybrid material with porphyrins. porphyrin–Multiwalled carbon nanotubes (MWNTs)  nanohybrid, 5-4 (aminophenyl)-10, 15, 20-triphenyl porphyrin and its photophysical properties including optical (TPP) and grapheme oxide molecules covalently bonded together via an amide bond (TPP-NHCO- SPFMWNTs )were used as absorbent for extraction of Co(II)   ions by solid phase extraction method. The complexes were eluted with HNO₃ (2M)10% V.V^-1 mthanol in acetone and determined the analyte by flame atomic absorption spectrometry.  The procedure is based on the selective formation of Co(II)  at optimum pH by elution with organic eluents and determination by flame atomic absorption spectrometry.The method is based on complex formation on the surface of the ENVI-18 DISK^TM disks modified porphyrin–Multiwalled carbon nanotubes (MWNTs)  nanohybrid, 5-4 (aminophenyl)-10, 15, 20-triphenyl porphyrin (TPP) and grapheme oxide molecules covalently bonded together via an amide bond (TPP-NHCO- SPFMWNTs ) followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effect of potential interfering ions, pH, TPP-NHCO- SPFMWNTs, amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about 1000mL providing a preconcentration factor of 600. The maximum capacity of the disks was found to be 568± 3 µg for Co²⁺. The limit of detection of the proposed method is 5ng per 1000mL.The method was applied to the extraction and recovery of Co in different water samples.

This study was designed to determine the predictors of literacy skills among Chinese preschoolers. There were 136 preschoolers aged ranged between three to six years old with their parents and teachers recruited in this study using a Multi-Stage Cluster sampling technique. Home-based learning activities were measured using Home Learning Environment Questionnaire (Lonigan & Farver, 2002). Meanwhile, children’s literacy skills were respectively assessed using Test of Early Reading Ability Third Edition (Reid, Hresko, & Hammill, 2001). This study found that preschoolers with higher level of literacy skills were came from families who practiced more home-based learning activities, and have highly educated parents and high family monthly income. Besides that, findings revealed that older children perform high level of literacy skills. The findings of this study imply that home learning was the most significant unique predictor of child’s literacy skills within all tested variables.

Groundwater management, particularly in arid regions, should be viewed holistically and linked to the sustainable management of the ecosystem. Only through consideration of the interaction between the groundwater and other environmental components can it be possible to elaborate a long-term program for rational groundwater use and protection. Ancient methods of groundwater management, such as the qanats system, provide an excellent demonstration of human ingenuity to cope with water scarcity. To make a qanat, one needs a source of water, which may be a real well, but can also be an underground reservoir (e.g., a cave with a lake) or a water-bearing geological layer, which can be recognized as a damp area in an otherwise arid region. When one has identified this source, a tunnel is cut to the farm or village that needs the water. Shafts are added for three reasons: as air supply, to remove sand and dirt, and to prevent the tunnels from becoming dangerously long. The shafts are not very far apart, and as a result, a qanat seen from the air gives the impression of a long, straight line of holes in the ground - as if the land has been subjected to a bombing run. Typically, the qanat becomes a ditch near its destination; in other words, the water is brought to the surface by leading it out of the slope. In fact, one creates an artificial artesian well and an oasis. There are about 22000 qanats in Iran with 274000 kilometers of underground conduits all built by manual labor. The amount of water of the usable qanats of Iran produce is altogether 750 to 1000 cubic meter per second. Qanats have been an ancient, sustainable system facilitating the harvesting of water for centuries in Iran, and more than 35 additional countries of the world such as India, Arabia, Egypt, North Africa, Spain and even to New world.

The success of every organization is highly dependent on how it attracts recruits, motivates and retains its quality workforce. In the current scenario, the organizations need to be more proactive to ensure the development of their workforce and commitment. Hence the organizations necessitate adopting the strategy to improve the employee’s Quality of Work Life (QWL) to satisfy both organizational objectives and employee needs. Quality of work life is the degree to which work in an organization contributes to material & psychological well-being of its members. The present study attempts to measure the level of level of perceived quality of work life among the employees of private manufacturing companies in the state of Tamilnadu, India. An attempt is also made to find out if the quality of work life has any significant relationship with job related variables and with demographic variables. The work related factors are combined in nine categories: Adequate & Fair, Compensation, Safe & Healthy Working Condition, Opportunity for Development, Opportunity for Growth & Security, Social Integration, Constitutionalism, Work & Total Life Space, Social Relevance & Working Life, Quality of Work Life Feelings and Overall Quality of Work Life.

In the present study, the FT-IR and FT-Raman spectra of 6-amino-2,3-dihydro-1,4-phthalazinedione (ADHPD) have been recorded in the region 4000-400 cm-1 and 3500-50 cm-1, respectively. The fundamental modes of vibrational frequencies of ADHPD are assigned. Theoretical information on the optimized geometry, harmonic vibrational frequencies, infrared and Raman intensities were obtained by means of Hartree-Fock (HF) and density functional theory (DFT) gradient calculations with complete relaxation in the potential energy surface using 6-311+G(d,p) basis set. The vibrational frequencies which were determined experimentally from the spectral data are compared with those obtained theoretically from ab intio HF and DFT/B3LYP calculations. A close agreement was achieved between the observed and calculated frequencies by refinement of the scale factors. The predicted first hyperpolarizability also shows that the molecule might have a reasonably good non-linear optical (NLO) behaviour. The calculated HOMO-LUMO energy gap reveals that charge transfer occurs within the molecule. Unambiguous vibrational assignment of all the fundamentals was made using the total energy distribution (TED).

Mobile banking system plays a major role in mobile commerce. As wireless networks are existed, today new generation of electronic commerce applications are emerged and expanded, that are known as mobile commerce. In this field one of services that served in bank industry with cell phones is mobile banking. Although many studies have been conducted to assess users’ satisfaction with mobile applications, none has focused on ranking the effective alternatives. So the goal of this article is to extract the effective alternatives of user’s satisfaction and rank them with VIKOR. The research extract 42 alternatives based on Delone and McLean’s Revised Model and chooses 21 effective alternatives by expert’s ideas and then ranking them. VIKOR shows that data accuracy and security are ranked as first and second alternatives.

Web Content is a core component of e-learning and includes issues such as pedagogy and learning and includes issues such as pedagogy and learning object re-use. Pedagogical elements are an attempt to define structures or units of educational material. For example, this could be a lesson, an assignment, a multiple choice question, a quiz, a discussion group or a case study. These units should be format independent, so although it may be in any of the following methods, pedagogical structures would not include a textbook, a web page, a video conference or podcast. When beginning to create e-learning content, the pedagogical approaches need to be evaluated. Simple pedagogical approaches make it easy to create content, but lack flexibility, richness and downstream functionality. On the other hand, complex pedagogical approaches can be difficult to set up and slow to develop, though they have the potential to provide more engaging learning experiences for students, Somewhere between these extremes is an ideal pedagogy that allows a particular educator to effectively create educational materials while simultaneously providing the most engaging educational experiences for students

Graham and Sloane [7] introduced the harmonious graphs and Singh & Varkey [11] introduced the odd sequential graphs. Gayathri and Hemalatha ( [2], [1]) introduced even sequential harmonious labeling of graphs. In [3], we extend this notion to k-even sequential harmonious labeling of graphs and further studied in [4-5]. Also we have introduced k-odd sequential harmonious labeling of graphs in [6]. Here, we investigate some results on k-even sequential harmonious labeling of graphs.

Interaction of various process parameters like initial chromium concentration (VI) (5-30 mg/l), pH (1-10), and adsorbent dosage (6-10 g/l) for chromium adsorption using custard apple powder were evaluated using central composite design (CCD) in response surface methodology. The CCD design in response surface methodology has been applied for designing the experiments as well as for full response surface estimation and 19 experimental data as per the model were used. The optimum conditions for better percentage removal of chromium from waste water with the concentration of 20 mg/l were as adsorbent dosage (9.9966 g/l), pH (2.7877) and initial chromium concentration (15.18693 mg/l). The high correlation coefficient (R2 =0.98929) between the model and the experimental data showed that the model was able to predict the better percentage removal of chromium (VI) from waste water using custard apple peel powder efficiently

Porous Silicon (PS) layers were prepared by electrochemical etching in a single-tank cell on the surface of single-crystalline p-type (100) silicon wafers, using hydrofluoric acid (HF) and ethanol (C2H5OH) in the volume ratio of 1:2. The surface and cross-section morphologies of the PS were observed from images obtained using Scanning Electron Microscope (SEM). Likewise, the porosity of the PS sample was determined using the parameters obtained from SEM images by geometrical method. SEM images indicated that, the pores were surrounded by a thick columnar network of silicon walls. This porous silicon layer can be considered as a sponge like structure. The X-ray diffraction (XRD) pattern showed the growth of PS layer on silicon wafer and the grain size of the PS layer was found to be around 60.2 nm. The effective refractive index of porous silicon was calculated using Effective Medium Approximation (EMA) analysis. The optical properties of PS were investigated using Fourier Transform Infrared (FTIR) spectroscopy and Photoluminescence (PL). The surface chemical bonds of the PS were observed by FTIR and the band gap of the PS sample was obtained from PL spectra. The efficiency of ethanol gas sensing properties of PS was investigated at room temperature. The sensor was found to operate with maximum efficiency at a concentration of 100 ppm hence, this PS material can be used as an effective sensor element to detect ethanol vapour.