Synthesis and Characterization of Niobium Nitride Nanowires
This project aims to explore the potential of inexpensive in-situ deposition of niobium nitride nanowires to improve electrical conductivity. Transition metal nitrides are well known for attributes such as superconductivity, high melting point, simple structure as well as excellent electrical and thermal conductivities. In particular, niobium nitride possesses exceptional hardness and high reflectivity, as well as being a stable field emitter, making it well suited to applications as a cold cathode material. Niobium nitrides are formed by the uptake of nitrogen by niobium. This is achieved by the exothermic formation of an interstitial solid solution of nitrogen atoms in the bcc lattice of the niobium. Existing research has established the possibility of preparing niobium nitride by heating niobium in nitrogen or ammonia over a range of temperatures, by heating niobium pentaoxide and carbon in the presence of nitrogen as well as by chemical vapor deposition of other niobium compounds, nitrogen or hydrogen. For the purpose of this study, a two-step process was used for synthesis. The benefits of a two-step process over direct ammonolysis are apparent, from the greater degree of freedom pertaining to parameter determination. Additionally, characterization of niobium pentaoxide nanowires synthesize under similar conditions is also made possible by terminating the reaction earlier. NbN nanowires were synthesized by annealing niobium pentaoxide nanowires at 850 oC for 2 hours. Subsequent characterization was done using Raman Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The presence of NbN nanowires via the conversion of Nb2O5 was ascertained by the absence of sharp peaks at 1000 cm-1 for Raman Spectroscopy and XRD plots. Field emission (FE) properties and electrical properties of NbN nanowires were then measured. NbN nanowires were found to have a high turn-on voltage, stable and relatively good field emission characteristics, demonstrating its potential as a cold cathode material. No current saturation was observed for an applied electric field of 0 to 6.0 V/ μm (5). This suggests a low degree of contact resistance for nanowires produced by this method of annealing, since the passage of electrons is not obstructed. Hence there will only be a small voltage drop between the SiO2 substrate and NbN nanowires. Samples containing NbN nanowires were dislodged by ultrasound to form an aqueous suspension of nanowires. A drop of suspension was dripped onto gold-finger substrates, and current-voltage (I-V) measurements of resultant nanowire bridges were taken. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Nanowire bridges obtained by heat-drying were denser and had better electrical properties than those obtained by evaporation to dryness. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Further work would include varying the cooling processes to observe any changes or deformation. Additionally, niobium nitride nanowires can be hybridized with carbon nanotubes (CNTs). A more in-depth comparison between niobium oxide and niobium nitride nanowires is also proposed, along with exploration of the nitrification of other transition metals.
Do SAT Problems Have Boiling Points？
The Boolean Satisfiability problem, called SAT for short, is the problem of determining if a set of constraints involving Boolean (True/False) variables can be simultaneously satisfied. SAT solvers have become an integral part in many computations that involve making choices subject to constraints, such as scheduling software, chip design, decision making for robots (and even Sudoku!). Given their practical applications, one question is when SAT problems become hard to solve. The problem difficulty depends on the constrainedness of the SAT instance, which is defined as the ratio of the number of constraints to the number of variables. Research in the early 90’s showed that SAT problems are easy to solve both when the constrainedness is low and when it is high, abruptly transitioning (“boiling over” ) from easy to hard in a very narrow region in the middle. My project is aimed at verifying this surprising finding. I wrote a basic SAT solver in Python and used it to solve a large number of randomly generated 3SAT problems with given level of constrainedness. My experimental results showed that the percentage of problems with satisfying assignment transitions sharply from 100% to 0% as constrainedness varies between 4 and 5. Right at this point, the time taken to solve the problems peaks sharply. Similar behavior also holds for 2SAT and 4SAT. Thus, SAT problems do seem to exhibit phase transition behavior; my experimental data supported my hypothesis.
Comfortable Equipment for Pedestrians
The phenomenon of pedestrians nowadays is still found. Due to frequent walking, sometimes our legs feel tired and hard to move. This is become the basis for developing tools that are convenient for pedestrians. An easy tool for humans is needed for our activities, especially walking. The Synergy between our hands and feet provides a big and significant contribution to the appliance. Normally, the movement of our hand gets along with its motion with a different side of the foot. When the right foot step, then the left hand is swung forward, and vice versa. The tools can be developed by utilizing a variety of systems. The system includes the tools concentric wheel and axles system, spring system, and pulley system. The concentric wheel and axles system is useful in controlling the rope. Movement on the rope could activate the entire system on the appliance. Wheel that related with the hand is three times bigger than wheel that related with pulley that is applied on foot. Spring system is able to lighten the pressure of the foot with a given upward force, and able to provide downward force when the spring returned to its original position. While the pulley system on the tool used to provide mechanical advantage two times is also useful to lighten the pressure of the foot when walking. The tools can be designed with simple, and able to provide benefits to users. By trial and error, it shows that the tool is able to lighten human’s activity when they walk. The tool can be able to lighten the leg’s load by utilizing arm muscles work. Utilization of the arm muscles which helps to ease the pressure of the foot can provide more benefits. One of them is that it can strengthen the arm strength, so the tool can be used as sport equipment. Utilization of the tool can also be reserved for special people who have difficulty in walking due to an accident or birth with leg defect.
Applied Red Palm Weevil Farming
The Red Palm Weevil is a kind of pest commonly found in all coconut and palm growing areas, causing considerable damage to palm trees. The pest at larva stage was found to be a popular food dish for both local people and visitors and has been commercially bred for consumption. This project aimed to develop a farming method to increase the quantity of red palm weevil larvae for commercial use, instead of the natural farming which fed the insects on rare natural materials. Firstly, the most appropriate food formula to boost the multiplication of red palm weevil using local raw materials was determined. Four food formula were developed: 1.combination of palm leaves, coconut fibers, and pig food, 2.palm leaves, coconut fibers, and rice bran,3. palm leaves, coconut fibers and cassava,4. a combination of crushed palm leaves and coconut fibers. The mixture ration were 1:1:1 for formula1-3 and 1:1 for formula 4. Equal number of the adult weevils were raised in the different food formula, the length and weight of the larvae obtained were measured every week for seven weeks. The gross weights and the effectiveness of the red palm weevil farming were analyzed using the feed conversion ratio (fcr), the daily growth rate, and the percentage increase in weight. It was found that. the weevils raised with food formula 1 yielded the larvae which grew the fastest with highest effectiveness. The most appropriate ratio of the food mix which yielded the satisfactory larvae size was determined to be 1:1:1 3.Next, experiment was carried out to improve the quality of the insect larvae for consumption. The larvae produced had some distinct smell which some consumers do not like.To improve the smell, the larvae were fed with the selected food mix added with minced fresh Pandanus leaves 2 days prior to consumption. Food mix with coconut fibers instead of Pandanus were used as control. Consumers were most satisfied with the larvae fed with added Pandanus leaves. Analysis of the food mix, larvae and Pandanus leaves found the common compound, Coumarins. In conclusion, our project found a suitable system of red palm weevil farming an alternative to conventional method which farmed the pest on cut palm trees. The new method resulted in the best yield of insect larvae with the highest consumer satisfaction and reduce destroying natural resource.
Universal computing sorting machine
The purpose of the study was to develop and create a semi-automatic multi-purpose sorting and counting machine of standard articles. Currently, there is a problem of equipping industrial enterprises as well as small trade companies and large retailers with computing sorting machines of standard products of a certain shape. We would like to fill this missing link up with a simple, compact and inexpensive device. Procedures The proposed research consisted of a consistent design of a virtual model of the device and its electronic-mechanical implementation. The virtual model is simulated by a computer program "SolidWorks" object, which graphically shows the operation of the future device. In the development of the computing sorting device standard electronic devices and their associated software have been used. The created simplified real model demonstrates the basic principles and characteristics of the proposed device. Data As an example for the implementation of the concept device a computing device for sorting coins, in circulation in Russia has been created. As a basic principle of sorting objects by their geometric and weight characteristics were used. It is important that the device is focused on the correct form of the objects of sorting (balls, rings, coins, regular polyhedrons, screws, nuts, etc). To confirm the effectiveness of the computing device of this type of sorting, a series of tests of counting of objects manually have been carried out . The effectiveness of the device is determined by comparing the time characteristics of manual and automatic sorting. Findings and conclusions As a result of research and work performed, we have concluded that: 1) The proposed device can be used in various industries. (for example, while sorting ball bearings.) 2) Such a computing sorting device may find it's application in various commercial enterprises: to assist cashiers in retail ATMs. 3) Can be used in payment terminals. 4) 4) After a certain modernization of the device it can be used for money encashment.
Applications of Biofuel Technologies for Third World Countries
Innovative, inexpensive, sustainable fuel for cooking and light can be produced with an anaerobic digestion biogas system. A biodigester was designed from parts that are locally available to purchase and maintain in a developing nation. The prototype was designed, built and the engineering was approved and tested. Research and testing of techniques used to produce biogas were recorded and analyzed. The digester successfully produced enough biogas to connect to a stove and burn. Research and testing continued on different ways to pressurize the biogas. A burn time of eleven minutes was recorded. A Bunsen burner was designed, again from locally available parts, in order to enhance the flame to use for cooking. The designed digester and burner worked satisfactorily to burn the biogas collected in the system. Using small scale tests, additional research and testing continued on the most efficient production of the biogas. Figure 1 shows the results of the small scale biogas testing. The results from the small scale testing showed that the best variables for producing biogas are using school compost, ie apples, bananas, oranges, cucumbers, grapefruit, grapes etc, which has been blended to acquire the most surface area with a 1:1 ratio. Figure 3 shows the results of a sample of methane (first three peaks) and of the biogas that was produced (last two peaks). The first peak is the nitrogen and the oxygen in the sample. The second peak is the methane and the third peak is carbon dioxide. The first biogas sample that was tested had no methane so there was an absence of the second peak. This was similar for Figures 4 and 5. Figure 6 shows a sample of the final biogas product which is producing methane as shown by the blue circle. Figures 3 through 5 lack a methane peak due to leaks in the biogas system and limited time within testing periods. The hypothesis was proved correct. An innovative, inexpensive, sustainable fuel for cooking and light using an anaerobic digestion system that can be built completely in developing nations such as Honduras was created. The biogas was ignited using a stove which provided heat for cooking. The biogas was not tested using a light; however, since the biogas can burn, this is theoretically possible. The final system achieved these goals.