...Experiment 5 - Cold Work, Recovery, Recrystallization and Grain Growth Objective To study the effects of cold working on the microstructure and mechanical properties of 70/30 Cartridge Brass. Background A small percentage of the energy expended in plastically deforming a material remains stored in the metal as an increase in internal energy. Changes are produced in both its physical and mechanical properties. Principally, there is a marked increase in hardness and electrical resistivity with the amount of cold working. Microstructurally, this increment in internal energy is associated with an increase in the dislocation density as well as the density of point defects, such as vacancies and interstitials. For most metals, the dislocation density increases from the values of 106-107 lines/cm2 (typical of the annealed state) to 108-109 after a few percent deformation and up to 1011 -1012 lines/cm2 after heavy deformation. At a more macrostructural level, the grains become markedly elongated in the direction of working and heavily distorted. This distortion is evident from a bending of annealing twins and from unevenness in etching caused by local strain inhomogeneities. While the increased hardness and strength that result from the working operation can be important, it is often necessary to return the metal to its initial condition by annealing. This usually means holding the cold worked metal at a temperature above about 1/3 of the absolute melting point for a period of time. The...
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...violated the Mauchly's Test of Sphericity, the Greenhouse-Geisser test was used to calculate the p-values. In the first experiment, squalane has no significantly different effect on bacterial growth at different temperatures (p=.071), as seen in Figure 1. Within temperature groups, squalane supplementation had a consistent effect of increasing growth (p<.000). This trend is evident in in Figures 2-4. In the second experiment, there was a significantly less bacterial growth over time in the minimal media than the nutrient broth independent of squalane supplementation (p<.000), which would be expected due to the former’s nutrient-poor composition....
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...Experiment: Growth Rate of Mealworms xxxxxx xxxxxx xxxxxxxx Integrated Natural Science Applications Problem Statement The growth of organisms is influenced by proper rearing conditions determined by temperature, light, air, and moisture (Lawson, 2001). However, literature indicates that mealworms are unlike most organisms as they are the second phase of development of the beetle. The beetle is an insect with grows and develops in four stages to reach complete metamorphosis from egg, larva, pupa, and adult (Schaffer, 2003). This research carries out a scientific experiment to identify the growth rate of the yellow mealworm, Tenebrio Molitor. The goal of the experiment will be to map out the rate of development of the beetle in its second life cycle in different conditions. The research will try to solve the following research questions: 1. What is the rate of growth of mealworms? 2. To what extent does temperature affect the rate of growth of mealworms? 3. To what extent does light, affect the rate of growth of mealworms? Relevance of Testable Question The research questions identified assist in identifying the research variables that will be tested. They also define the scope and extent of the study and determine the extent of the scientific research. Therefore, from the research questions the variables are rate of growth, temperature, time, and light. Literature Review Mealworms are the second stage of development of insects whose growth and development...
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...environments. In this lab experiment, several tasks took place. In order to be able to observe the colony morphology of both Archaea, they were grown on an agar surface that allowed them to form colonies of characteristic colour and appearance. In order to observe the physiology of both Archaea on the effect of salt concentration, pH, and temperature, they needed to be placed on agar plates and incubated for two weeks. Being incubated for two weeks, allowed the halophilic archaeal cultures to grow. The objective of this experiment was to determine the morphological and biochemical characteristics along with the growth requirements of the halophilic Archaeans; Halobacterium salinarum NRC-1 and Haloferax volcanii DS2. Introduction The domain, Archaea, possesses prokaryotic cells and has a cell wall that contains no peptidoglycan. Archaea contain rRNA that is unique to the Archaea as indicated by the presence of molecular regions. Archaea usually live in extreme environments and include methanogens, extreme halophiles, and hyperthermophiles. One reason for this is that the ether-containing linkages in the Archaea membranes are more stable and are able to withstand higher temperatures and stronger acid concentrations. The other two domains of life are Bacteria and Eukarya. Unlike the Bacteria and the Eukarya domains, the Archaea domain has membranes composed of branched hydrocarbon chains that are attached to glycerol by ether...
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...One of the oldest strategies to prolong shelf-life of food especially meat products is to reduce the storage temperature; where the concept of refrigeration came up. A direct linear relationship was strongly established between temperature and bacterial growth, long decades ago, and low temperature has been confirmed to have a bacteriostatic effect (Ratkowsky et al., 1982). It has been shown that spoilage rate of poultry stored at 10 °C and 15 °C is twice and three times that of 5 °C, respectively (Jay, 2005). Anbalagan et al. (2014) have shown that the total vial count in chicken sample stored in freezers at -18 °C has decreased from 156×105 cells/gram to 35×102 cells/gram in five days. However, microorganisms in general and bacteria in particular...
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...Effects on the gas exchange of Chylamydomonas under controlled conditions Introduction: Is gas availability a limiting factor for algae growth this spring in the Louisiana State University (LSU) lake system? For three weeks, we observed the effect that changes in gas availability had on the rate of algae growth in the LSU Lake System to determine the optimal growth of Chlamydomonas. To study the effect that temperature had on the Chlamydomonas population, we compared three different environments: high (control), medium, and low exposer to the gas present in a room. This study led to our next question: how does gas availability affect chlorophyll concentration this spring in the LSU lake system? The null hypothesis for this experiment is: if gas availability changes in the lakes, then the Chlamydomonas population will not change. The alternative hypothesis for this experiment is: if temperature changes in the lakes, the Chlamydomonas population will change. Predictions As gas availability is increased in the lakes, the growth of the Chlamydomonas will also increase. Therefore, decreasing the availability in the lakes will decrease Chlamydomonas growth. As temperature is increased in the lakes, chlorophyll production will also increase. (2) Methods: Samples of water were taken from the lakes and among other things the depth, water clarity, temperature, pH were measured. These measurements were taken to compare the chlorophyll of algae concentration to the Chlamydomonas...
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...THE EFFECTIVENESS OF TRICHODERMA REESEI IN THE BIOCONTROL OF FUSARIUM OXYSPORUM AT DIFFERENT TEMPERATURES A project report submitted for examination in fulfillment of the requirements for the course Unit SBT 414: RESEARCH PROJECT in the Bachelor of Science (Microbiology and Biotechnology) Degree. AMWAYI ANGELA LUKALE I23/3384/2008. Signature…………………… Date……………………….. SUPERVISOR: DR. P.M WACHIRA Signature …………………… Date………………………. SCHOOL OF BIOLOGICAL SCIENCES. UNIVERSITY OF NAIROBI. 2011-2012 DECLARATION iii DEDICATION iv ACKNOWLEDGEMENT v ABSTRACT vi CHAPTER ONE 1 INTRODUCTION 1 1.1 JUSTIFICATION 2 1.2 OBJECTIVES 3 1.2.1 Broad objective 3 1.2.2 Specific objectives 4 CHAPTER TWO 4 LITERATURE REVIEW 4 2.1 Trichoderma Spp. 4 2.2 Fusarium species 8 CHAPTER THREE 11 MATERIALS AND METHODOLOGY. 11 3.1 Media Preparation 11 3.2 Isolation of pathogenic fungi (Fusarium spp). 12 3.4 Dual culture inoculation 13 CHAPTER FOUR 13 RESULTS 13 CHAPTER FIVE 18 DISCUSSION 18 CHAPTER SIX 20 CONCLUSION AND RECOMMENDATION 20 REFERENCES 21 8. Dudley, N. S. (2007). Pathogenicity of four Fusarium species on Acacia koa seedlings. Missoula, MT: U.S. Dept. of Agriculture, Forest Service, Northern Region, Forest Health Protection. 21 12. James, R. L. (2002). Biological control of Fusarium oxysporum and Fusarium proliferatum on young Douglas-fir seedlings by a nonpathogenic strain of Fusarium oxysporum. Missoula, MT: U.S. Dept. of Agriculture, Forest Service...
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...front legs are used for grasping prey. The water strider lays eggs on the edge of water on rocks or aquatic plants. These insects eat other insects no matter if they are dead or alive. They have sucking mouth used to eat either terrestrial insects that have accidentally fallen on the water’s surface or other aquatic insects like mosquito larvae as it comes to the surface (National Wildlife Federation, 1996-2013). There are several factors that can change the stability and growth of this insect’s reproduction and population growth. Abiotic factors like water, temperature, and light can change the population but biotic factors like plants or other organisms can alter it also. If change within an environment happens then change to the organisms within the environment will happen as well (Elzinga, 2004). Abiotic Factors Abiotic factors are non- living components like water, temperature, and light. A rapid increase or decrease in any of these factors would have an effect on this species. Water is important to the water strider population because it is here that it lives and obtains its...
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...GREEN HOUSE EFFECT INTRODUCTION In temperate countries some economically important plants that cannot grow outside at a very low temperature during the winter are grown in glass-walled & glass-roofed growth chambers (known as glass houses)exposed to sunlight. Glass houses are also used in sub tropiacal regions during winter months & relatively cold high altitude for high value horticultural annual crops including flowers on a cmmercial scale as well as for research work especially for breeding of new varities & crop physiological & pathological studies. Temperature within the glass house rises because of the glass of the roof & walls through it allows entry of sunlight with little obstruction,resist the escaping of the reflected light of longer wave-lengths rich in infra-red rays resulting in a heat built up. Such glass houses are called green housesas the light & heat within such houses prove very effective for profuse growth of green plants. The property of trapping heat by carbon di oxide & other gases of the atmosphere is similar to the glass cover of green house that reasists the escaping of heat radiated from inside of the house.As such, these atmospheric gases are called green house gases that resist the escaping of radiated heat from the earth by absorbing infra red rays & particularly reflecting the trapped heat back to earth's surface.this phenomenon is therefore called the green-house effect in wicch certain atmospheric gases act in a manner similar to the glass...
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... | |2. Does more or less water keep an orchid alive and well? | |3. What is the productivity of an ant colony in warm vs cold temperatures? | |4. Which is the best fertilizer to help keep tomato plants alive longer and foster better growth? | |5. Do purple flowers or pink flowers attract more hummingbirds? | |6. Do ladybugs keep insects from eating leaves on plants? | |7. Does beer or tomato juice keep bugs away from eating tomato plants? | |8. What type of soil causes saguaro cactus grow the highest? | |9. What is ant food preference for proteins, lipids, and carbohydrates? | |10. Does sunlight affect the growth rate of strawberries? | Select the two best inquiries from above and complete the following table: |Selected inquiry: |1. What should the optimal water frequency be for a |3...
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...reproduce by producing enzymes to catabolise polysaccharides. Upon maturation the parent cell passes its genetic information to the bud which then becomes a genetic copy of the original cell and adds to the population. A growth curve demonstrates the four stages of population growth for a yeast cell as follows: Diagram 1. Reference: http://classconnection.s3.amazonaws.com/33/flashcards/602033/jpg/bacterial_growth_curve1320203184633.jpg Lag phase: Indicates the process of assimilation of nutrients by the initial population. Growth is restricted as the yeast are adjusting to their environment and synthesising cellular macromolecules. Exponential phase: Growth is increasing rapidly at this stage and competition for resources is minimal allowing for the yeast to bud at maximum capacity. Stationary phase: The population is now stabilising as resources become depleted and competition increases; yeast cells are dying at a similar rate of budding due to the accumulation of cytotoxic wastes and metabolic byproducts, such as ethanol, are produced. Death phase: Due to the exhaustion of resources and increasing levels of toxic waste the population of yeast starts to decrease. Budding cannot occur at this point as there is limited space for growth reducing the population over time....
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...viticulture practices and technology etc. Although there are various factors affecting the quality of wine grape, this literature review will focus on the climatic and soil characteristics which influence the grape wine quality in New Zealand. The soil characteristics and climate has always had a significant impact on vineyard practices as recognized by viticulturists for centuries (Sluys, 2006). According to Smart et. al, (1985), all viticulturists agree on the conclusion that soil, climate and cultural management are the three most important sub-systems within the whole vineyard environment. An example of this relation among these sub-systems is given in figure 1. The concept applies that “soil, climate, and cultural practice have direct effects and alternations to canopy...
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...SBI4U Date: Designing a Controlled Experiment Step 1: Defining the Problem Every scientific investigation begins with the question that the scientist wants to answer. The questions addressed by scientific inquiry are based on observations or on information gained through previous research, or on a combination of both. Just because a question can be answered doesn’t mean that it can be answered scientifically. Step 2: Defining the Dependent and Independent Variable Dependent Variable (DV) | Variable the experimenter measures, after making changes to the IV that are assumed to affect the DV. | Independent Variable (IV) | Variable the experimenter manipulates (i.e. changes) – assumed to have a direct effect on the dependent variable. | Note: In many cases, the investigator does not manipulate the independent variable directly. He/She collects data and uses the data to evaluate the hypothesis, rather than doing a direct experiment. For example, the hypothesis that more crimes are committed during a full moon can be tested scientifically. The number of crimes committed is the dependent variable and can be measured from police reports. The phase of the moon is the independent variable. The investigator cannot deliberately change the phase of the moon, but can collect data during any phase he/she chooses. Why is the scientist limited to one independent variable per experiment? As the aim of an experiment is to see what happens when one thing is changed and how...
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...methodology and development of a kinetic model S. Ghosh; R. Chakraborty; G. Chatterjee; U. Raychaudhuri* Centre for Medicinal Food and Applied Nutrition, Department of Food Technology and Biochemical Engineering, Fax: 91-033-24146822, Jadavpur University, Kolkata, 700032, India. E-mail: utpal31@hotmail.com ABSTRACT Natural vinegar is one of the fermented products which has some potentiality with respect to a nutraceutical standpoint. The present study is an optimization of the fermentation conditions for palm juice vinegar production from palm juice (Borassus flabellifer) wine, this biochemical process being aided by Acetobacter aceti (NCIM 2251). The physical parameters of the fermentation conditions such as temperature, pH, and time...
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...EFFECTS OF CLIMATE CHANGE ON POULTRY PRODUCTION 1.0 INTRODUCTION Poultry are birds such as the domestic fowl, Turkey, Duck, Goose, Ostrich e. t. c which are of economic importance to man. Their production is one of the livestock production with significant contribution to human food (Demeke, 2004). It is the primary supplier of eggs and meat as a source of income and employment to people compared to other domestic animals (Avila, 1985). They are raised with relatively low capital investment and readily available household labour. For instance poultry egg contains 74% water, it is a good source of high protein and it is often used by nutritionist as a standard reference for evaluating other protein foods. Studies have shown that the level of performance of poultry does not depends on inherited capacity, but also to a great extent upon the environment (Campbell and Lasley, 1975). The environmental conditions affecting the performance, relative humidity, light, sunshine prevailing at a given time, housing system and ventilation. High temperature and humidity have some negative effects on poultry such as an increase on poultry body temperature: a decrease on feed consumption ( Cowan and Michie, 1978; Howlider and Rose, 1987) and feed efficiency. High temperature also results to a reduction in poultry live weight ( Mowbray and Sykes, 1971), growth speed and high mortality (Arjona et al., 1988) in addition to a decrease on productivity and quality of the eggs (Ozbey and Ozoelk, 2004)...
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