Use of Landsat imagery for mapping soil and land resources for development planning in parts of Northern Karnataka,India†

Abstract

A soil and land resources map of an area in Northern Karnataka, India, has been prepared using false colour composite of Landsat imagery, supplemented by field investigations on 1:250000 scale. The soil and land resources map thus prepared formed the basis for preparing thematic maps such as land capability, land irrigability and suggested land use. Areas suitable for agriculture, horticulture, forestry, pasture and other uses are highlighted in the suggested land use map. This information could well be used by planners and administrators for effecting developmental plans connected with agriculture on scientific lines at regional or state level.     

Influence of interface properties on fracture behaviour of concrete

Hardened concrete is a three-phase composite consisting of cement paste, aggregate and interface between cement paste and aggregate. The interface in concrete plays a key role on the overall performance of concrete. The interface properties such as deformation, strength, fracture energy, stress intensity and its influence on stiffness and ductility of concrete have been investigated. The effect of composition of cement, surface characteristics of aggregate and type of loading have been studied. The load-deflection response is linear showing that the linear elastic fracture mechanics (LEFM) is applicable to characterize interface. The crack deformation increases with large rough aggregate surfaces. The strength of interface increases with the richness of concrete mix. The interface fracture energy increases as the roughness of the aggregate surface increases. The interface energy under mode II loading increases with the orientation of aggregate surface with the direction of loading. The chemical reaction between smooth aggregate surface and the cement paste seems to improve the interface energy. The ductility of concrete decreases as the surface area of the strong interface increases. The fracture toughness (stress intensity factor) of the interface seems to be very low, compared with hardened cement paste, mortar and concrete.     

EFFECT OF EVAPORATIVE COOLING STORAGE ON RIPENING AND QUALITY OF TOMATO

Tomatoes (Lycopersicon esculentum Mill cv. Rupali) ripened in evaporative cooling (EC) storage conditions (20°C–25°C, 92–95% RH) were compared with control fruits stored under room conditions (28°C–33°C, 45–65% RH) during summer in Mysore. EC ripened tomatoes on the 15th day reached 100% ripening index (RI) with a value of 2.48 for the ratio of redness to yellowishness (a/b) and hue angle (θ) of 22.1° whereas the control tomatoes on the same day reached a maximum 83.3% RI with a/b ratio of 1.59 and a hue angle of 32.9°. Higher development of chroma and total color difference were exhibited by EC stored tomatoes than control samples. The lycopene content of EC ripened fruits double that of the control. EC stored fruits showed lower values for rupture and shear stresses. The rate of moisture loss for control fruits was 6.5 times as great as for EC stored tomatoes.     

废镍催化剂回收制备纤维状氢氧化镍

研究从废旧镍催化剂中回收镍以制备氢氧化镍。采用酸浸法,在90℃下用1mol／L硫酸浸没废镍催化剂,从中提取镍。向净化后的含镍溶液中加入NaOH,分别采用3种不同的方法,即尿素水解、传统方法和水热方法制得3种不同的氢氧化镍,分别命名为Ni（OH）2-U,Ni（OH）2-C和Ni（OH）2-H。与传统方法相比,采用水热方法制得的氢氧化镍具有更好的结晶度。Ni（OH）2-C和Ni（OH）2·H都含有β-Ni（OH）2与a-Ni（OH）2·0．75H20的混合相,而Ni（OH）2．U只含有a-Ni（OH）2．0．75H20相。TEM观察显示Ni（OH）2-U样品具有棒状结构。在这3种样品中,Ni（OH）2-U表现出最好的电化学活性。     

Dependence of thermal conductivity in micro to nano silica

This work presents the measurement of thermal conductivity of nano-silica particles using needle probe method. The validation test of thermal probe was conducted on ice and THF hydrates using our experimental set up and the results are satisfactory when compared with the literature data. The nano silica used in this study is with particle sizes in the range 50–1000 nm. The sand powders sieved in different sizes ?<75 and 75  μ m ?>? d ?>? 250  μ m were also studied to probe the particle size dependence on thermal conductivity. Thermal conductivity decreased by about 70% in silica nano powders.     

Study of optical characteristics of tin oxide thin film prepared by sol–gel method

In this paper, we present details of preparation of tin oxide (SnO $_{{2}})$ thin film by sol–gel process. The film was synthesized on a glass (Corning 7059) plate by dip coating method. Here, we used tin (II) chloride as precursor and methanol as solvent. Optical characteristics and physical properties like refractive index, absorption coefficient and thickness of thin film were calculated from the study of transmission spectrum (wavelength vs transmission curve) data given by UV/VIS Spectrophotometer. Effect of number of coatings on transmittance and refractive index was also examined. It was observed that refractive index decreases with the number of coating and transmission value was more than 80% at wavelength greater than 450 nm in all cases. Structural analysis was studied by XRD measurement by using diffractometer which confirms tetragonal rutile structure of SnO ₂ . Surface morphology was analysed from SEM micrograph and change in morphology on number of coat was discussed.     

Indigenous development and airworthiness certification of 15–5 PH precipitation hardenable stainless steel for aircraft applications

In this paper, we discuss the optimization of chemical composition, processing (forging and rolling) and heat treatment parameters to obtain the best combination of mechanical properties in case of a Fe–15Cr–5Ni–4Cu precipitation hardenable stainless steel. The ε-copper precipitates that form during aging are spherical in shape and coherent with the matrix and principally provide strengthening in this alloy. The orientation relationship is found to be Kurdjumov–Sachs (K–S), which is common in fcc–bcc systems. Results obtained from metallurgical evaluation (mechanical property and metallography) on 15–5 PH alloy during type certification on 3 different melts were used for the optimization, attempted in this study. The mechanical properties following strain deformation has been carried out using optical microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). In the aged conditions, the 15–5 PH alloy exhibited brittle failure with extensive cleavage and/or quasicleavage fracture. This paper reports all results and also factually shows that indigenously developed and produced 15–5 PH stainless steel matches in its properties with the equivalent aeronautical grade precipitation hardening stainless steels globally produced by internationally renowned manufactures.     

Processing Techniques for Difficult-to-treat Ores by Combining Chemical Metallurgy and Mineral Processing

This paper is concerned with a review of published literature on the processing of difficult-to-treat ferrous and nonferrous ores that have very fine liberation size and have constituent minerals with similar properties for which the conventional mineral processing techniques are ineffective. By altering mineralogy either pyrometallurgically or hydrometallurgically, the low cost methods of mineral processing could be applied on ores which are complex and refractory in character.

It briefly reviews methods such as magnetizing roasting and direct reduction for ferrous ores and discusses the pyrometallurgical pre-treatments on nonferrous ores, such as sulfidizing roasting, roast-flotation, segregation process and matte separation process, and hydrometallurigcal pre-treatments to extract valuable metal values by applying leach-precipitation-flotation method, and ion flotation.

Application of a combination of chemical metallurgy and mineral processing methods to solid waste materials, in particular, steel plant wastes, nonferrous slags, smelter flue dusts and anode slimes have also been briefly discussed.     

Experimental evaluation of a 35 kVA downdraft gasifier

Energy conversion systems based on biomass are particularly interesting because biomass utilization effectively closes the carbon cycle besides achieving self-sustainability. Biomass is particularly useful for highly populated and agriculture dependent economic nations like China and India. A compact and cost effective downdraft gasification system was developed. The present paper describes an experimental investigation on a biomass based gasifier engine system with a capacity of 35 kVA for power generation application. The problem of cooling and cleaning the hot and dirty gas from the gasifier has been satisfactorily solved by the effective cooling and filtration system. The gasifier developed is observed to be operation friendly. The quality of gas was evaluated in terms of its composition, conversion efficiency and total particulate matter. The maximum output of the power plant was obtained at the combustion zone temperature of 850oC. The experimental investigations showed that the percentage reduction in total particulate matter is 89.32%. The conversion efficiency of the biomass gasifier is found to be dependent on the operation conditions and fuel properties of the gasifier. The optimum value of equivalence ratio was observed to be 0.3134 for achieving the maximum gas conversion efficiency of the present gasifier configuration.     

Model reduction technique applied to a nuclear reactor turbine system

A method has been developed for determining a low-order model for a large multivariable system from its measured input-output data. It is based on the use of a matrix pseudo-inverse to estimate the parameters of the model which minimize the sum of the squares of the errors between the responses of the original system and the low-order model at the sampling instants. A recursive algorithm is proposed which makes it useful for on-line applications. The method is used to obtain low-order models for a nuclear reactor turbine system. The outputs of the low-order models and those of the large-scale model (consisting of 11 non-linear differential equations and 36 algebraic equations) are compared for the turbine system.