Required amount of Ag (Silver) nanoparticles are suspended in water to prepare silver nanofluids with particle volume concentrations of 0.005%, 0.01% and 0.03%. Nanoparticles of diameter 54.97nm – 66.81nm in range being dispersed in water; stirring action is effected after mixing with water in order to produce required particle volume fractions. Besides, the solution is sonicated continuously for approximately 30 min using ultrasonic vibrator, whose frequency ranges from 0 to 100Hz, to breakdown the nanoparticle agglomeration. Scanning electron microscope (SEM), X-Ray diffraction, Particle size, and Zeta potential analyser are further used to characterize the silver nanoparticles. Fig.2 reports the SEM image of silver nanoparticles taken for 45000X. It is witnessed that nanoparticles are well distributed with certain level of assortment. Fig.4 depicts the zeta potential distribution versus total counts of the silver nanoparticle. The zeta potential is the measure of electric potential at the slip plane between the bound layer of diluent molecules surrounding the particle, and the bulk solution. The measurements of zeta potential enable predictions about the storage stability of colloidal systems. As it is a well known fact that the charged particles with high zeta potential value, do not aggregate due to electrostatic repulsion. It is evident from Fig.4 that the zeta potential values from -70mV with total counts of 10,000 and increases to an average potential -30mV with maximum counts of 170,000. It is obvious that majority of the particles possess high electro-negative values which, confirms a high stability and good size distribution of silver nanoparticles. The procedure involves dispersing the nanoparticle in the base fluid. M...
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Colloidal silver is particles of silver broken down or mixed into liquid. In the early 20th, ,century colloidal silver or as it is more popularly known “silver water” was marketed as a cure for tumors; now in alternative medicine it is referenced as a cure all with healing properties.
Physical Chemistry Laboratory Manual, Physical Chemistry Laboratory, Department of Chemistry, University of Kentucky, Spring 2006.
The nano-thermal analysis method is capable of studying the specific regions of a sample irrespective of its composition. In a multi-component sample, the analysis methods make it possible for the researchers to distinguish between the different components and identify the different characteristics found in each of the sample (Craig, 2002). During the analysis of any sample, the nano-thermal method does not necessarily require the physical alteration of the sample. In its place, it is capable of analyzing any sample through surface studies.
The dielectric constant found decreases monotonically in the lower frequency and it is independent at higher frequency. The high value of the dielectric constant at low frequencies can be attributed to the accumulation of charge carriers near the electrodes and at higher frequency the dipoles or polar molecules are unable to orient themselves in the direction of the applied field, hence the dielectric constant appears to decrease or is steady with increasing frequency [58]. The dielectric constants (εꞌ & εꞌꞌ) were found to increases with temperature at a fixed frequency for all electrolyte films due to the greater freedom of movement of the dipole molecular chains of polymer electrolytes at high temperatures. At lower temperatures, the dipoles are rigidly fixed or tightly bound in the dielectric material; therefore the field cannot change the condition of the dipoles. As the temperature increases, the dipoles become comparatively free and they respond to the applied electric field causes the change in the induced energy at the dipole site and consequently enhance the dipole motion
They have a larger surface area in proportion to their volume. This enables them to interact with different types of biological systems and provides a wide variety of possibilities (Nuruzatulifah, Nizam, & Ain, 2015). The nanoparticles can be seen by transmission electron microscopy (TEM). When there is one nanoparticle, it is called a primary particle. When there is more than one, it is called a secondary particle. In order to measure these particles, they need to be suspended in a solution (Pruneanu, Coros & Pogacean, 2015). Dyed nanoparticles or internally fluorescent nanoparticles barely interact with cellular proteins which is what the study requires. They are also quite easy to manipulate. They can be easily internalized into cells and can be programmed to go to specific sites (Wolbeis,
Investigating Heat Loss From a Container Planning We are investigating heat loss from a container and how it is affected. We could change: Room temperature Surface area Amount of water Use a lid Insulate around it Colour of tin We could measure / observe: Amount of time Temperature We will change: Surface area We will measure / observe: Temperature (every minute for 5 minutes) Our question is: Does surface area effect the rate of heat loss? We will keep these the same: Colour of tin Room temperature Amount of water Use a lid Insulate around it Preliminary investigation = == ==
The molar specific heats of most solids at room temperature and above are nearly constant, in agreement with the Law of Dulong and Petit. At lower temperatures the specific heats drop as quantum processes become significant. The Einstein-Debye model of specific heat describes the low temperature behavior.
heat will stay in the cup and can only escape by rising to the surface
The heat makes the molecules in the mixture expand and move slower than when they are in colder temperatures (source 1). The molecules are like people when it comes to how they react to heat and coldness. When the molecules are cold, they like to be very close to one another and the molecules move fast because they are “shivering” (source 2).This is just a one of many examples and comparisons that I am going make throughout this paper. Some of the examples will be very cheesy. I am going to give a warning. When the molecules are hot, they like to be far apart from one another (source 1). They even might start to sweat like humans, too. The molecules have some energy too, but the molecules just do not have as much energy when they are hot. They like to be lazy like many humans do in hot weather (source 1).
The next type of heat transfer is convection. Convection is heat transferred by a gas or liquid. Such as dumping hot water into a cold glass of water, making the water overall warmer. The last type of heat transfer is radiation.
Cengel, Y. A., & Boles, M. A. (2011). Thermodynamics: An engineering approach (7th ed.). New York, NY: McGraw-Hill.¬¬¬¬
Conduction is the process by which heat is transferred from on solid to another. When a solid is heated the molecules inside, which are normally almost static, start to vibrate. When another solid is brought into contact with the heated solid the energy from the vibrating molecules at the edge of the heated solid is transferred to the outer molecules of the other solid.
The process of conduction between a solid surface and a moving liquid or gas is called convection. The motion of the fluid may be natural or forced. If a liquid or gas is heated, its mass per unit volume generally decreases. If the liquid or gas is in a gravitational field, the hotter, lighter fluid rises while the colder, heavier fluid sinks. For example, when water in a pan is heated from below on my stove, the liquid closest to the bottom expands and its density decreases. The hot water as a result rises to the top and some of the cooler fluid descends toward the bottom, thus setting up a circulatory motion. This is also why the heating of a room by a radiator depends less on radiation than on natural convection currents, the hot air rising upward along the wall and cooler air coming back to the radiator from the side of the bottom. Because of the tendencies of hot air to rise and of cool air to sink, radiators are positioned near the floor and air-conditioning outlets near the ceiling for maximum efficiency.
Have any of you wondered about the magic that occurs within a hot hand? The hot hand is a small pouch that contains mysterious elements that combines to start a reaction that produces heat. There is a specific field of chemistry that studies the heat associated with reactions, and today we begin our journey learning about this form of chemistry called thermochemistry! Thermochemistry is a fascinating field of chemistry that contains new terms and ideas that need to be understood in order to proceed into the mathematical applications of thermochemistry. We are going to create “I wonder…” statements to help with learning about these new terms while we read the
There are formulas to calculate electrical conductivity and resistivity. Conductivity is defined as the inverse of resistivity (a high conductivity means a low resistance), I=V/R or current equals voltage over resistance. This is known as Ohm’s Law. Electrical resistance is calculated by the formula, R=V/I or resistance equals voltage over current. Ohm’s law however does not hold true if temperature changes. Materials that obey Ohm’s law are known as ohmic or linear because the potential difference across it varies linearly with the current. In addition, whether or not a material obeys Ohm’s law its resistance can be described in bulk resistivity. Furthermore, over sizable ranges of temperature, this temperature depe...