eChapters

The ingestion of mycotoxin-contaminated feedstuffs by animals leads to adverse effect on animal health and the effects are more serious in monogastric animals depending on the species and the susceptibility to toxins within the species. Ruminants are less susceptible to mycotoxins than monogastric animals because of biotransformation of mycotoxins to non-toxic metabolites in rumen by rumen microbiota (Fink-Gremmels, 2008).

The economic loss in livestock arising due to mycotoxicosis is enormous apart from being a health risk. Indian economy is heavily affected by mycotoxins. It was estimated that 10 million dollars were lost in India’s export within a decade due to groundnut contamination with mycotoxins (Vasanthi and Bhat, 1998). Many developing countries have realized that reducing mycotoxin contamination in foods will not only improve the health and production in animal, but also increase the raw material exports (international trade) to other countries. The following strategies are to be adhered strictly to reduce the mycotoxins contamination of crops in the field.

1. Early harvesting

Early harvesting reduces the fungal infection of crop in the field. Early harvesting and threshing of groundnuts results in lower aflatoxin levels and higher gross returns of 27% than in delayed harvesting (Rachaputi et al., 2002).

To study the characteristics of microorganisms, it is essential to culture and growth them. Growth is the increase in cell number which can be obtained by providing proper physical and chemical conditions. Medium is a substance that provides nutrients for growth and multiplication of microorganisms. Any medium for the cultivation of bacteria and fungi must provide certain basic nutritional requirements which include a carbon, nitrogen, phosphate and various mineral nutrients. The following is the medium composition for the isolation and culturing of different biocontrol agents

The isolation of microbes is commonly done using serial dilution technique.

1. Trichoderma

Trichoderma is one of the important biocontrol agents. The colonies first produce mycelial growth and then turn yellow and finally produce a dark green color mat.

The discovery and use of synthetic chemicals has contributed greatly to the increase of food production industry by controlling pest and diseases. However, the use of synthetic chemicals has raised number of ecological problems apart from increasing the cost of cultivation. In recent years, scientists have directed their attention in exploring the potential of beneficial microbes for plant protection measures. Biocontrol agents exhibit antagonistic activity against plant pathogens and activate resistance mechanisms in the host despite improving plant growth. In agricultural soils the nutritional condition is depleted hence beneficial microbes decrease and increase the pathogenic microbes. To ensure the sustained availability of biocontrol agents mass production technique and formulation development protocols has to be standardized which also increases the shelf life of the formulation. Though these agents have a very good potential in the management of Pest and Diseases it can not be used as cell suspension under field conditions. The cell suspensions of these biocontrol agents should be immobilized in certain carriers and should be prepared as formulations. The organic carriers used for formulation development include peat, turf, talc, lignite, kaolinite, pyrophylite, zeolite, alginate, pressmud, sawdust, vermiculate, etc.

Introduction

Studies on biocontrol agents have revealed the presence of a diverse range of antifungal metabolites derived from amino acid, polyketones and isoprenoid biosynthetic pathways, each of which has distinctive regulatory points and is subjected to different stimuli within organisms. In this experiment, the extraction of secondary metabolites from the culture of T. viride and Chaetomium globosum will be demonstrated.

Entomopathogenic nematode (EPN) viz., Heterorhabditis, Neosteinernema and Steinernema have been recovered from many regions of the world. They selectively infect many insects and a few other arthropods but do not adversely affect mammals or plants. They are actually vectors of pathogenic bacteria, cause relatively rapid death of the host (24 – 48 h) and show considerable potential in biological control of insect pests in the integrated pest management systems.

EPNs are similar to insect parasitoids in that the immature form develops at the expense of one host individual; they are ecologically similar to both parasitoids and arthropod predators because the host individually killed. However, these nematodes differ from predators and parasitoids in two ways: (1) the nematode is mutualistically associated with a bacterial pathogen which actually kills the host, and (2) the pathogenicity of the bacterium has a great influence on the efficacy of the system (Ehler, 1990). The purpose of this chapter is to introduce EPN as biocontrol agents in this refresher course and to provide an overview of some current issues in biological control of insects with particular emphasis on their relevance to the use of EPNs.

Biological control is defined as the action of natural enemies which maintains a host population at levels lower than would occur in the absence of the enemies. Natural enemies will include parasitoids, predators, nematodes, microbial pathogens and their gene products. Entomologists generally divide biological control into two categories: (1) natural biological control which is effected by native or coevolved natural enemies in the native home (origin) of a given insect and (2) applied biological control which due to human intervention. Applied biological control is further divided into classical biological control (introduction of exotic natural enemies) and augmentative biological control (enhancement of natural enemies already in place).

“SOIL” the term is derived from Latin word “solum” which means, “floor”. Soil has been a defining component of humanity since the beginning of civilization. It holds the clues of past cultures, it supports the web of life connecting all ecosystems, provides materials to build houses, and provides the base for our food, feed, fiber and even some biofuels.

Soils are complex mixtures of minerals, water, air, organic matter, and countless organisms that are the decaying remains of once-living things. It forms at the surface of land and is the “skin of the earth.” Soil is capable of supporting plant life and is vital to life on earth. There are several general roles that soils play:

Mineral

A mineral is defined as “a natural substance, usually inorganic, having a definite chemical composition and commonly a definite molecular arrangement which is usually expressed in geometric form”.

There are over 100,000 different types of soil in the world, each with its own set of characteristics. If any soil is dug deep, one can see that it is made of layers, or horizons. The horizons together form a soil profile. Each profile tells a story about the life of a soil.

The development of soil profile is a constructive process where in disintegrated materials resulting from weathering of rocks and minerals get converted into a soil body. Soil Individual or Polypedon is a natural unit of soil that differs from its adjoining unit on the landscape in one or more properties. In modern soil taxonomy, polypedon is the unit of soil mapping. Apedon is the smallest volume recognizable in nature that can be called “a soil”.

The phenomena related to the retention and movement of water in soils, its uptake and translocation in plants and its loss to the atmosphere are all energy related. The more strongly water is held in the soil, the greater is its energy. It means that if water is to be removed from a moist soil, work has to be done against the adsorptive forces. The water movement is always from a zone where the free energy of water is high (standing water table) to one where the free energy is low (a dry soil). This is called soil water energy concept.

17.1. Soil Water Potential

The free energy of soil solids for water is influenced by:

i) Matric force: the attraction of the soil solids for water (adsorption) which markedly reduces the free energy (movement) of the adsorbed water molecules.

Soil Reaction

Soil reaction is an indication of the acidity or basicity of the soil and is measured in pH units. The pH scale ranges from 0 to 14, with 7.0 as neutral point. From pH 7 to 0, soil is increasingly acidic. From pH 7 to 14, soil is increasingly alkaline.

Pure H₂O ionizes to a very small degree, though to a measurable extent, so that it has the following equilibrium: both H+ and OH^- are in concentrations of 10^-7 moles L^-1.

Soil organic matter (SOM) is one of the most complex materials existing in nature. Besides the organic constituents in undecayed plant and animal tissues, SOM contains both living and dead microbial cells, microbially synthesized compounds and an unending array of derivatives of these materials produced as the result of microbial activity. Soil organic matter contains most of the naturally occurring organic compounds. Some components of SOM are undoubtedly unique to the soil environment, particularly those involving inorganic-organic complexes.

The Carbon Cycle

The element that serves as a corner stone for cell structure is carbon. Plant tissues and microbial cells contain approximately 40 to 50% of C on dry weight basis. Yet, the ultimate source is the CO₂ of the atmosphere. The CO₂ is converted into organic C by the action of photoautotrophic organisms (higher plants and green algae). It has been estimated that the vegetation on earth’s surface consume some 1.3 x 10¹⁴ kg of CO₂ per annum which is about V₂₀ of the total CO₂ supply of the atmosphere or ¹/₁₀₀₀ of that in the ocean. Soil carbon constitutes the largest terrestrial pool of carbon.

The synthesis of humic substances is the least understood and the most intriguing aspect of humus chemistry. Studies on this subject are of enduring and continued research. Several pathways have been identified for the formation of humic substances during the decay of plant and animal remains in soil, the main ones being shown in Fig. 26.1.

Soil pollution indicates the presence in the soil of any chemical or substance out of place and/or present at an abnormally higher concentration so as to adversely affect any non-targeted organism. Soil pollution often cannot be visually perceived or directly assessed, thus rendering it a latent danger. The Status of the World’s Soil Resources Report identified soil pollution as one of the main soil threats affecting global soils and the ecosystems services provided by them. Concerns about soil pollution are growing in every region. Recently, the United Nations Environmental Assembly (UNEA-3) adopted a resolution calling for accelerated actions and collaboration to address and manage soil pollution. This consensus, achieved by more than 170 countries, is a clear sign of the global relevance of soil pollution and of the willingness of these countries to develop concrete solutions to address the causes and impacts of this major threat.

29.1. Sources of Soil Pollution

The main anthropogenic sources of soil pollution are the chemicals used in or produced as byproducts of industrial activities, domestic, livestock and municipal wastes (including wastewater), agrochemicals, and petroleum- derived products. These chemicals are released to the environment accidentally, for example from oil spills or leaching from landfills, or intentionally, as is the case with the use of fertilizers and pesticides, irrigation with untreated wastewater, or land application of sewage sludge. Soil pollution also results from atmospheric deposition from smelting, transportation, pesticide applications and combustion of many substances as well as radionuclide fallouts from atmospheric weapons testing and nuclear accidents. New concerns are being raised about emerging pollutants such as pharmaceuticals, endocrine disruptors, hormones and toxins, among others, and biological pollutants, such as micropollutants in soils, which include bacteria and viruses.

Soils play a vital role in the health of ecosystems in the world. Soils connect with air, water, rocks and organisms and are responsible for a multitude of functions in the global ecosystem services. These functions include providing habitat for most living things, air composition and quality, temperature regulation, carbon and nutrient cycling, water cycling and quality, and natural waste recycling. Mankind cannot survive without these soil functions.

30.1. Habitat

Soils are the environment in which plants grow. They provide heat, nutrients and water to nurture plants to maturity. These plants, together with other plants and organisms, create ecosystems. These plants then provide valuable habitat and food sources for animals, bacteria and other things. Ecosystems depend on the soil and soils determine the nature and kind of ecosystems.

Horticulture is an art and science of growing plants. It is the practice of engaging ailing people in various horticultural activities such as gardening and flower arrangements in order to improve their physical, mental and spiritual health. Research confirms that health benefits escalate manifold when people connect with nature and plants by viewing and/or interacting with them. Major benefits of horticultural therapy includes sensory simulation and mood enhancement, mental relaxation, improvement of memory and concentration and an overall feeling of wellness. Horticulture therapy also helps in cultivating positive emotions and provides a meditative mood. It eases both physical and emotional pains and also improves social skills. It is proven that a simple viewing of a garden benefits a person both physically and mentally.

This practice has been used as therapy for centuries. In 1798, Dr. Benjamin Rush, considered as the “Father of American Psychiatry” documented that gardening has positive effects on mentally ill patients. Following World War, II gardening was used as a form of occupational therapy for war veterans. The concept of using nature to improve human health began to gain credibility in 1970’s. Rachel and Stephen Kaplan (1989) found that natural environments had relaxing and restoration benefits for people. The Journal of Therapeutic Horticulture, a peer-reviewed publication of the American Horticultural Therapy Association, has published authentic research papers since 1986. The American Horticultural Therapy Association (AHTA) serves to promote and advance horticultural therapy as a therapeutic intervention and rehabilitative approach. Degrees and certificate programs in horticultural therapy are offered at several colleges and universities and information is available on AHTA website.

Horticultural therapy is a worldwide practice and recognized as an effective treatment for clients of all ages and abilities. It is being used in several diverse settings including hospitals, rehabilitation centres, youth outreach and recovery programs, nursing homes, senior care facilities, prisons, mental health facilities, schools, botanical gardens etc. The client is engaged in horticultural activities facilitated by some trained therapists to achieve specific and documented goals. AHTA believes that horticultural therapy is an active process that occurs in the context of an established treatment plan where the process itself is considered as the therapeutic activity rather than the end product.

Horticulture therapy is a growing profession in rehabilitation and addiction centers, vocational centers, youth mental health programs, hospitals and nursing homes, and old age homes or senior citizen centers, mental health centers, schools and colleges.

Wood apple is also known as kaith, kavat, curd apple and monkey fruit. It is found almost throughout the country. It is one of the very hardy tree found growing in arid and semi arid regions of the country. Hill region of northern India and Ceylon are supposed to be its native land (Reuther et al., 1967). Chundawat (1990) thought it to be a native of India and Sri Lanka. It is a popular tree of forest, Indoor yard garden and can be exploited for regular cultivation in dry areas. The cricket ball size fruits have sweet and aromatic pulp, eaten fresh or used for drinks, chutneys, jellies etc. In forests of Rajasthan, it is commonly found in Aravalli range and Hadoti Plateau.

The Internet of things connects the devices over Internet. The devices can communicate with each other and can be monitored and controlled remotely. The IoT is a system with interrelated computing devices, digital and mechanical machines, objects, animals or people each with an unique identifiers (UIDs ). It has the ability to transfer data over a network without human intervention. The Internet of Things is simply a network with Internet connecting the objects to collect and exchange the data. This chapter covers the basics of Internet of Things and its components.

2.1 Characteristics of IoT

Internet of Things can be used to design products for businesses. The added value to the businesses over IoT is created by the information which is collected by connected devices. The process has five phases of lifecycle, first phase is ‘create phase’, where sensors collects the data from environment. This data can generate the information. Second is ‘communicate phase’ where data generated in first phase is communicated to the required destination. Third is ‘aggregate phase’ where collected data over network is aggregated by device itself. Fourth is ‘analyse phase’ where aggregated data is used to generate patterns and use it to control and optimize the process. Fifth is ‘act phase’ where actions are taken on the basis of information extracted from the aggregated data.

The characteristics of IoT may vary from one domain to other. Few characteristics are listed as follows-

Floriculture has flourished with a considerable growth and a useful crop diversification option, particularly for small farmers over the past three decades. The commercial production of the cut greens has started in India in recent years and has huge demand in the market. They are suited for year round production with low investment and less care and maintenance. Cut greens or fillers are an important component of the floricultural industry and their commercial value depends on vegetative characters, such as stem length, leaf colour, density and side branching. Cut foliages (leaves and stems), which are attractive in form, colour and freshness, are lasting and in great demand. They have various other uses in making attractive fresh floral designs and floral arrangements, such as bouquets, wreaths, decoration of house interiors, etc. Evergreen plants with green, silver or variegated leaves are usually used and species with berries are now also becoming popular. Fillers are critical components in most arrangements as the flowers themselves,used to increase the volume and size of the bunch and provide colour contrast. These floral produce have various other uses in making attractive fresh floral designs and floral arrangements, such as bouquets, wreaths, decoration of house interiors, etc. Colour, freshness, stem length, freedom from pests, fragrance and vase life are important quality aspects of fillers. In the International market, fillers accounts for about 16 percent of the total trade by volume with an annual turnover of more than Rs 800 crores including selling of ornamental leaves, filler flowers, dry and dyed flowers along with berries and capsules. On the contrary, fillers representvery less quantum with poor quality in the domestic market and are unsuitable for cut flower bouquets. Their share in the market is very low and fetches nominal rates.

Volumetric Analysis

Measurement of volume of reagents required for the completion of reactions

Also called titrimetry – most widely used techniques of chemical analysis

Rapid, accurate, convenient and inexpensive

Secondary standard solution

Solution of chemicals which lack one (or) all the properties for a primary standard

A solution standardised by titrating a primary standard

Less accurate than a primary standard

Theory

Bulk density of the food material play an important role in many applications such as drying, storing, separation of undesirable material, determining the purity of seeds, grinding, maturity evaluations, design of storage structures, etc. It is an important parameter in packaging requirement and is often 2-20% of true density. Bulk density is the density of material when stacked or packed in bulk. Bulk density of powder can be determined under loose conditions. Loose packing is defined as the state obtained by pouring a powder sample into a vessel without any consolidation.

Bulk density

Bulk density of the food material can be defined as the ratio of weight of an untapped material to its volume including the contribution of the inter-particulate void volume. There are two kinds of voids, voids between particles and void within particles. Weight of the material can be determined by weighing balance. Volume can be determined by measured dimensions or using liquid or gas or solid displacement methods.

Aim

To determine the tapped bulk density and flowability of the food powder.

Materials required

Raw material (powder)

Measuring cylinder

Electronic weighing balance

Tapped bulk density of the powder

Tapped bulk density is measured for powdery samples. The volume is measured after tapping the powdery material so that the product is adjusted to inter-granular spaces, but it cannot eliminate all the inter-granular spaces. The tapped density is an increased bulk density attained after mechanically tapping a container containing the powder sample.

Theory

Porosity is a physical property characterizing the texture and the quality of dry and intermediate moisture foods. Porosity means inter-granular space. It is the measure of void space between the materials. Porosity may be defined as the percentage of volume of inter-grain space to the total volume of grain bulk. Porosity depends on size, shape, dimension, and roughness of grain surface.

The porosity of an unconsolidated agricultural material can either be determined experimentally using the porosity tank method or theoretically from bulk and true densities of the material. Porosity can be determined from the difference between bulk volume of a porous material and its volume after destruction of all voids by compression. Porosity determination requires the knowledge of the total or apparent volume, and the void volume included in the material matrix; their difference is also known as the particle volume.

Theory

The specific gravity is defined as the unit weight of the product mass divided by the unit weight of distilled water at 4°C. The unit density is obtained by measuring the volume and weight of a unit product. Sometimes it is required to compare the density of the product to the density of water. This comparison is in the form of ratio and is termed as the specific gravity.

Specific gravity also known as relative density is the ratio of density of a substance to the density of a standard substance at the same temperature and pressure. For solids and liquids the standard substance is water while for gasses it is air. The specific gravity of food material play an important role in design of storage bins, conveying equipments, separation equipments, etc. The specific gravity is frequently used to solve the various phase relationships, including void ratio, porosity and degree of saturation together with the moisture content and unit weight. It is also used in calculations associated with the grain size analysis, consolidation and compaction. Pycnometer method, which is a standardized vessel for determining specific gravity. It involves a standard container of accurately defined volume used to determine the specific gravity of solids and liquids.

Aim

To determine the thermal conductivity of the agricultural materials probe method.

Materials required

Thermal conductivity probe

Stainless-steel sample container

Grain or powder sample

Graph sheet

Power source

Theory

Specific heat is defined as the amount of heat needed to raise the temperature of one kg of the material by one degree at constant pressure without a change in state. With food materials, specific heat is a function of different components of a food, moisture content, temperature, and pressure. Specific heat is an important parameter in thermal analysis of food processing and equipment used in heating or cooling of foods. The numerical values of specific heat of the food materials are used in designing food processes and processing equipment. It can be used to calculate the heat load imposed on the refrigeration equipment by the freezing of foods. An apparent specific heat is used in freezing or thawing and in most food processing applications.

The specific heat of a food increases as the product moisture content increases. In unfrozen foods, specific heat capacity is relatively constant with respect to temperature. However, for frozen foods, there is a large decrease in specific heat capacity as the temperature decreases. The specific heat of a material can be determined experimentally by static (adiabatic) calorimetry or differential scanning calorimetry. It can be also predicted quite accurately with the help of a number of empirical equations. The equations are empirical expressions, obtained by fitting experimental data into mathematical models. The mathematical models are based on one or more constituents of the food. Since water is a major component of many foods, a number of models are expressed as a function of water content.

Theory

The energy available in food is expressed in unit is called joules or calories. One kilocalorie is equal to 4.184 kilojoules. The kilocalorie is defined as the amount of heat required to raise the temperature of 1 kg of water by 1°C. The calorific/ energy value of foods is usually determined using the instrument called bomb calorimeter. It is working based on the principles of calorimetry. Basically, this device burns a food sample and transfers the heat into a known mass of water. It measures the heat produced when the food sample is ignited by an electric spark in the presence of oxygen and platinum which acts as a catalyst. The quantity of food sample to be tested is placed inner part and known volume of water is taken in outer part of the bomb calorimeter. When the food sample is electrically ignited, the surrounding water absorbs the heat produced. The energy value of the food is calculated by measuring the rise in temperature of water.

Theory

The amount of moisture in a product is given on the basis of the weight of water present in the product and is usually expressed in percent. Moisture content is designated by (i) wet basis (wb) and (ii) Dry basis (db). The moisture content on dry basis is more simple to use in calculation as the quantity of moisture present at any time is directly proportional to the moisture content on dry basis.

Theory

Indirect methods are based on the measurement of electrical properties of the grain that depends upon moisture content. There are two indirect methods namely (i) electrical resistance and (ii) dielectric methods are used. The electrical conductivity or resistance of a product measures its moisture content at a given compaction and temperature. The electrical resistance is depends on its moisture content, degree of compaction, grain temperature and impurities present in the sample. The universal digital moisture meter measures the electrical resistance of the grain at a given compaction. Universal moisture meter gives fairly accurate readings of moisture content on wet basis. In dielectric method, grain moisture content can be measured with the help of dielectric properties of the grains.

Theory

Fluidized bed drying is a method of drying by keeping the material in fluidized/ floating condition inside a chamber by hot air. In this drying process higher rate of moisture migration takes place.

Aim

To study the working principle and cleaning efficiency of air-screen seed cleaner cum grader

Apparatus required

Lab model air-screen seed cleaner cum grader

Seed sample

Weighing balance

Aim

To determine the effectiveness of inclined belt separator

To determine the capacity of inclined belt separator

Materials required

Inclined belt separator

Weighing balance

Feed material

Sample divider

Aim

To evaluate the performance of the gravity separator.

Materials required

Specific gravity separator

Weighing balance

Sample divider

Stopwatch

Grains

Aim

To determine the efficiency of groundnut decorticator

Apparatus required

Manually operated groundnut decorticator

Weighing balance

Groundnut pods

Theory

Removal of outer sheath is called husking and removal of kernel from maize from maize cob is called shelling. The performance of the sheller is expressed in terms of capacity, percentage of unshelled kernels (corn) and percentage of breakage. The above terms are defined as:

Theory

Paddy parboiling is a hydrothermal process where the paddy is partially boiled to gelatinize the starch. During the gelatinization process the void of the rice kernel are filled and become hard on drying resulting minimum breakage and maximum head rice recovery. The nutrients are also absorbed into the inner mass and loss of nutrient is avoided. In general, the steps are involved in parboiling process are (i) Soaking (ii) Steaming (iii) Drying.

Rubber-roll Sheller consists of two rubber rolls rotating in opposite direction at different speeds. One of the roll is fixed while the other is adjustable to obtain desired clearance between them. The rolls are driven by mechanically. The adjustable roll normally runs about 25% slower than the fixed one. A feeder feeds paddy uniformly to the machine (Fig.27.1). Paddy is fed in thin layer through the clearance between two rubber rolls, rotating in opposite directions at different speed. Difference in speeds of the rolls develops a shearing force on grain surface results in the splitting, breaking and separating the husk from the grains. One part of the husk is subjected to shearing forces whereas the other part in contact with the slower roll is under compression and is thus subjected to breaking forces. Husking is done by the action of these forces. The clearance between them should be smaller than the mean thickness of paddy and may be adjusted subsequently by judging the shelling efficiency. If the gap between rolls is properly adjusted, it can shell up to 95% of paddy fed to it. At decreased gap excess pressure results more breakage of grain and can also cause coloring of shelled rice. During shelling the faster roll should have a peripheral speed of 10 -13 m/ s, while the slower roll 8-10 m/s.

Specifications

These structures are generally used for the storing grain in the bags. The length of the structure is about twice the width or greater than that. Special care should be taken to make the side walls, floor and roof in constructing the structure. The walls are made of bricks or stones laid either in lime mortar (1:2) or cement mortar (1:6). The thickness is restricted to a minimum of 37.5 cm or maximum of 45 cm. The height of the walls on which the trusses are placed is kept about 5.5 m. Each of the structures is provided with two large size doors of 2.4 × 2.4 m and top ventilators.

Aim

To design a screw conveyor

Theory

The screw conveyor consists of screw blade, screw shaft, coupling, tubular trough, cover, inlet and outlet gates, bearings and drive mechanism.

A shaft with spiral screw revolves in the tubular trough. The screw shaft is supported by end and hanger bearings. The rotation of screw pushes the grain along the trough.

The screw blade or flight is a continuous one-piece helix, shaped from a flat strip of steel welded on to the shaft.

The screw shaft is usually a joint less tube with thick sides and a high tensile strength to reduce the weight.

Description

Screw conveyor is one of the equipment used in material handling to convey the material horizontally. The screw conveyor consists of screw blade, screw shaft, coupling, tubular trough, cover, inlet and outlet gates, bearings and drive mechanism. A shaft with spiral screw revolves in the tubular trough. The screw shaft is supported by end and hanger bearings. The rotation of screw pushes the grain along the trough. The pitch of a stranded screw which is the distance from the center of one thread to the center of the next thread is equal to its diameter

Description

Bucket elevator is one of the equipments used in the material handling to convey the material vertically. The lab model bucket elevator (Fig.34.1) consists of number of buckets/cups arranged to an endless flat belt. The belt with cups run vertically and cups are placed at a particular interval in the belt. The belt is wrapped over two pulleys, one at the top is called head pulley which receives power from an electrical motor 0.5 hp through suitable power concentration and rotates at required rpm. The belts, cups and pulleys are mounted on a steel frame. The grain from the hopper is reaches to the bottom pulley. The bucket is filled with grains during upward movement and is discharged at the top due to the centrifugal force. An outlet is provided at the top to collect the discharge grain. The capacity depends on the bucket size and seed of operation. For proper discharge of the material, the weight of the material in each cup should be equal to the centrifugal force created due to rotation.

Aim

To determine cost of operation of processing machineries with available data.

Total operation cost

For calculation of cost of operation of processing machineries, two types of cost viz., fixed cost and variable cost to be estimated.

Aim

To study the different materials used for chain survey

Theory

Chain surveying is the method of land surveying in which only linear measurements are made. This method of surveying quit simple and it requires only a chain, a tape, few ranging rods and few arrows. It is used for securing data for exact description, marking the boundaries of land and preparing the maps of the area to show various details. The term details mean a natural or man-made feature at the ground surface.

Aim

To determine the area of given field by triangulation method of chain survey

Materials required

Metric chain

Measuring tape

Ranging rods

Chain pins

Aim

To find out the area of given field by cross-staff survey method

Materials required

Cross-staff

Metric chain

Measuring tape

Ranging rods

Chain pins

Aim

To determine the area of the given field by radiation method using a prismatic compass.

Materials required

Prismatic Compass

Tripod

Measuring tape

Arrows

Ranging Rods

Aim

To determine the area of given field by intersection method of plane table survey.

Materials required

Tripod

Plane table

Plumbing fork

Level tube

Magnetic compass

Alidade

Measuring tape

Ranging rods

Drawing sheet

Pins, pencil and eraser