Soil Moisture Flow Modeling with Water Uptake by Plants (Wheat) under Varying Soil and Moisture Conditions

A variably saturated soil moisture flow model is developed for planted soils with depth varying properties by incorporating a nonuniform macroscopic root water uptake function. The model includes spatial and temporal variation of the root density with dynamic root growth for simulating water uptake by plants along with the impact of soil moisture availability. The governing partial differential moisture flow equation integrated over the depth with a plant water uptake term is solved numerically by the implicit finite difference method using an iterative scheme. The model is first tested for barren soils for two profiles considering constant and depth varying soil characteristics under constant inflow condition. The results obtained are later tested with experimental data available in the literature. A nonuniform plant water uptake term is subsequently incorporated in the model and water uptake by wheat plants under different soil moisture availability conditions is studied. Finally, the moisture flow model is validated with field data of rain fed wheat (Triticum aestivum) using a dynamic root growth model for a layered root zone soil profile. The simulated soil moisture regime of the layered root zone shows a reasonably good agreement with the observed data.     

Using data mining synergies for evaluating criteria at pre-qualification stage of supplier selection

A company must purchase a lot of diverse components and raw material from different upstream suppliers to manufacture or assemble its products. Under this situation the supplier selection has become a critical issue for the purchasing department.The selection of suppliers depends on number of criteria and the challenge is to optimize selection process based on critical criteria and select the best supplier(s). During supplier selection process initial screening of potential suppliers from a large set is vital and the determination of prospective supplier is largely dependent on the criteria chosen of such pre-qualification. In the literature, many judgments based methods are proposed and derived criteria selection from the opinion of either the customers or the experts. All these techniques use the knowledge and experience of the decision makers. These methods inherit certain degree of uncertainty due to complex supply chain structure. The extraction of hidden knowledge is one of the most important tools to address such uncertainty and data mining is one such concept to account for such uncertainty and it has been found applicable in many scenarios. The proposed research aims to introduce a data mining approach, to discover the hidden relationships among the supplier’s pre-qualification data with the overall supplier rating that have been derived after observation of previously executed work for a period of time. It provides an overview that how supplier’s initial strength influence its final work performance.     

ΛCDM type Heckmann–Schuking model and Union 2.1 compilation

We study a ΛCDM type cosmological model in Heckmann-Schucking space-time, by using 287 high redshift (.3 ≤ z ≤ 1.4) SN Ia data on observed absolute magnitude along with their possible error from Union 2.1 compilation. We use the χ² test to compare Union 2.1 compilation observed data and the corresponding theoretical values of the apparent magnitude (m). It is found that the best fit value of (Ω _m )₀, (Ω_Λ)₀ and (Ω _σ )₀ are 0.2940, 0.7058 and 0.0002, respectively, and the derived model represents the features of an accelerating universe which is consistent with the recent astrophysical observations.     

Efficient Halogenation of Aromatic Systems Using N‐Halosuccinimides in Ionic Liquids

A simple, rapid and highly regioselective green protocol has been developed for the halogenation of aromatic systems with N‐halosuccinimides using room temperature ionic liquids (ILs) as novel and recyclable reaction media to produce the corresponding halogenated aromatic compounds in high to quantitative yields. N‐Halosuccinimides show enhanced reactivity in ionic liquids thereby reducing the reaction times dramatically and improving the yields substantially.     

Long term effects of inorganic fertilizer inputs on crop productivity in a rice-wheat cropping system

Three levels of N (40,80,120 kg N ha^-1) and P (0,17.5,35 kg P ha^-1), and 2 levels of K (0,33 kg K ha^-1) were tested for 19 years in rice and wheat crops of a rice-wheat cropping system in a fixed layout of 3×2×2 factorial partially confounded design along with one control and 3 replications. From this trial, data of 7 treatments, i.e. 0-0-0, 40-35-33, 80-35-33, 120-35-33, 120-0-0, 120-35-0 and 120-0-33 kg ha^-1 N-P-K respectively were compared for yield trends, changes in response functions, soil organic -C and available N,P,K status. Soil organic - C decreased in unfertilized plots by 62% (over initial value of 0.45%) but increased by 44, 40 and 36% in plots receiving 120-35-33, 120-35-0 and 80-35-33 kg ha^-1 N-P-K respectively. Available N was also greatest in these same three treatments. Available soil P increased by about 5 fold in 15 years in treatments supplied with fertilizer P, but no significant change was detected in treatments without P addition. Yields of rice and wheat exhibited linear declining trend in all treatments. The highest rate of decline (89 kg ha^-1 year^-1 in rice and 175 kg ha^-1 year^-1 in wheat), however, was found when 120 kg ha^-1 N was applied alone. The least rate of decline of 20 kg ha^-1 year^-1 in rice and 58 kg ha^-1 year^-1 in wheat was observed when 40-35-33 kg ha^-1 N-P-K respectively was applied to both the crops. At currently recommended levels of NPK (120-35-33 kg ha^-1), the rate of decline in yields was 25 kg ha^-1 year^-1 for rice and 62 kg ha^-1 year^-1 for wheat. Possible causes of these yield declines are discussed.     

Fabrication and characterization of nanostructured indium tin oxide film and its application as humidity and gas sensors

This paper reports the synthesis and characterization of nanocrystalline indium tin oxide (ITO) and its application as humidity and gas sensors. The structure and crystallite size of the synthesized powder were determined by X-ray diffraction. The minimum crystallite size was found 5 nm by Debye–Scherrer equation and confirmed by transmission electron microscopy image. Optical characterizations of ITO were studied using UV–visible absorption spectroscopy and Fourier transforms infrared spectroscopy. Thermal analysis was carried out by differential scanning calorimetry. Further, the ITO thin film was fabricated using sol–gel spin coating method. The surface morphology of the fabricated film was investigated using scanning electron microscopy images. For the study of humidity sensing, the thin film of ITO was exposed with humidity in a controlled humidity chamber. The variations in resistance of the film with relative humidity were observed. The average sensitivity of the humidity sensor was found 0.70 MΩ/%RH. In addition, we have also investigated the carbon dioxide (CO₂) and liquefied petroleum gas sensing behaviour of the fabricated film. Maximum sensitivity of the film was ~17 towards CO₂. Its response and recovery times were ~5 and 7 min respectively. Sensor based on CO₂ is 97 % reproducible after 3 months of its fabrication. Better sensitivity, small response time and good reproducibility recognized that the fabricated sensor is challenging for the detection of carbon dioxide.     

Liquid‐Liquid‐Liquid Phase Transfer Catalysis: A Novel and Green Concept for Selective Reduction of Substituted Nitroaromatics

The selective reduction of nitroaromatics to the corresponding amines is an important transformation since many aromatic amines exhibit biological activities and find a multitude of industrial applications, being intermediates for the synthesis of dyes, pharmaceuticals and agrochemicals. A variety of nitroaromatics dissolved in organic solvents was reduced by using aqueous sodium sulfide, and tetrabutylammonium bromide (TBAB) as the phase transfer catalyst by choosing appropriate concentrations which resulted in three immiscible liquid phases. Compared to L‐L PTC, the L‐L‐L PTC offers much higher rates of reaction, better selectivities and repeated use of catalyst. The selectivities for the desired products were 100%.     

Utilization of bagasse fly ash generated in the sugar industry for the removal and recovery of phenol and p-nitrophenol from wastewater

Bagasse fly ash, a waste generated in local sugar industries, has been converted into a low cost adsorbent. The product so obtained has been characterized and used for the removal of phenol and p-nitrophenol. Investigations include the effect of pH, sorbent dosage, phenol concentration and the effect of surfactants on the uptake of phenol and p-nitrophenol. The adsorption data follow both Langmuir and Freundlich models. Isotherms have also been used to obtain the thermodynamic parameters of the process. Some experiments have also been performed with a view to recover phenols and have in-situ chemical regeneration of the spent carbon column. © 1998 SCI.