Papers by Keyword: Pulverization

Abstract: Li₄Ti₅O₁₂/Sn was successfully synthesized by a solid-state method using the High Energy Ball Mill Machine as anode for Lithium-Ion batteries. The addition of various (10%, 20%, 30%) Sn-micro particle is aimed to enhance LTO's conductivity and capacity. Characterization of the sample's structure was performed using X-ray diffraction (XRD), which expose the presence of TiO2 rutile and Sn in each sample. The surface area of samples observed using Brunner-Emmet-Teller (BET), which indicates the different surface area of each Sn addition. Scanning electron microscopy (SEM) suggested agglomeration and poor distribution appear in every sample. Cyclic voltammetry (CV) was performed to measure the battery's performance. Two peaks occur as a sign of reversible reaction. The impedance of Li₄Ti₅O₁₂/Sn measured using electrochemical impedance spectroscopy (EIS), the test performed before and after Cyclic voltammetry (CV), each test showed the different result for each sample. Other than EIS and CV, Charge-Discharge (CD) also performed, examinations in different C-rate were performed, and higher Sn concentration leads to lower stability in high C. The result reveals that the addition of 20% Sn optimizes Li₄Ti₅O₁₂ in enhancing capacity and conductivity.

Abstract: The effects of a rotary slasher with two different shapes of knives (L and Y-shaped) at three cutting speeds (1830, 2066 and 2044 rpm) were studied on percentage of pulverization of sweet potato vine passing through the sieve (< 28 mm²). The results showed that all the treatments were significant at p 0.05 and p 0.01 significance level. The best result was by Y-shaped knife with highest vine pulverized percentage of 82.76 % and a mower speed of 2440 rpm had the finest vine pulverized percentage of 90.48 %. The best performance for interaction effects between knife shapes and speeds of mower was achieved by the Y-shaped knife and a mower speed of 2440 rpm resulting in an average percentage of 92.62 % of pulverized vine.

Abstract: Snowfall process is analyzed from the perspective of computer simulation in this paper, the dynamic properties and the static properties of snow particles are abstracted based on particle system theory. The snow particles movement is simulated with wind and no wind. To solve the problems of the blur of snowing environment and firn phenomena, the paper puts forward a method of applying pulverization to snowing virtual environment. The tests show that the simulation methods of snowfall and pulverization are effective and real, which are suit for real-time virtual environment.

Abstract: Different methods of cutting fluid application are used on turning of a difficult-to-machine steel (SAE EV-8). A semi-synthetic cutting fluid was applied using a conventional method, minimum quantity of cutting fluid (MQCF), and pulverization. By the minimum quantity method was also applied a lubricant of vegetable oil (MQL). Thereafter, a cutting fluid jet under high pressure (3.0 MPa) was singly applied in the following regions: chip-tool interface; top surface of the chip; and tool-workpiece contact. Two other methods were used: an interflow between conventional application and chip-tool interface jet and, finally, three jets simultaneously applied. In order to carry out these tests, it was necessary to set up a high pressure system using a piston pump for generating a cutting fluid jet, a Venturi for fluid application (MQCF and MQL), and a nozzle for cutting fluid pulverization. The output variables analyzed included tool life, surface roughness, cutting tool temperature, cutting force, chip form, chip compression rate and machined specimen microstructure. It can be observed that the tool life increases and the cutting force decreases with the application of cutting fluid jet, mainly when it is directed to the chip-tool interface. Excluding the methods involving jet fluid, the conventional method seems to be more efficient than other methods of low pressure.

Abstract: The effect of annealing treatment on the structure, gaseous hydrogen characteristics and electrochemical properties of the La _0.67 Mg _0.33 Ni _2.5 Co _0.5 alloys was investigated. Alloy structure analyses show that all of the alloys consisted of complex phases such as (La,Mg)₂(Ni,Co)₇ phase, (La,Mg)(Ni,Co)₃ phase and La(Ni,Co)₅ phase. The homogenization of composition was improved by annealing treatment. Gaseous hydrogen characteristics were also improved after annealing. The pulverization of the alloy particles was reduced after annealing treatment, which could improve the cycling stability. Electrochemical experiments show that all of the alloy electrodes exhibited good activation characteristics, that annealing treatment improved the maximum discharge capacities of the alloy electrodes from 371.1 mAh/g (as-cast) to 387.7 mAh/g (1173K). The cyclic stability of alloy electrodes was also improved after annealing. However, the high rate dischargeability characteristics were deteriorated.

Abstract: A novel biomass pulverization technology was presented, and its performance is affected by many aspects, which have not been studied and optimized. This paper mainly concerns with a detailed study of the effect of rotor speed. The pulverization tests were conducted in a lab-scale crushing system and the results show: higher rotor speed improves the hit probability between blades and materials, enhancing the impacting and grinding effects. Thus higher rotor speed generates much finer particles. Meanwhile the energy consumption shows increasing trend with increasing rotor speed.

Abstract: The near-dry deep hole drilling system was taken as object in this study，and the contrast experiment between the deep hole drilling system and the traditional（wet）deep-hole drilling system，including the cutting force，the tool wear，the surface quality and the chip-break have been done. The results show that the near-dry system drill stability and have better effort in cooling，lubrication，chip removal effective. The tool life and surface quality within the hole are better，at the same time，it can greatly reducing the amount of cutting fluid，the costs and the pollution of the environment. So we can get a conclusion that it is an ideal system in green drilling process.

Abstract: Wet jet milling is a new technology for the pulverization of powders, in which streams of slurry, higher than 100m/s, collide in the channel made of diamond. The effect of processing parameters was investigated in the system of BN/SiO2 mixed powders. The particle size after milling was evaluated by the measurement of BET surface area. The BET surface area of BN increased with increase in the number of milling, in the mixture ratio of SiO2/BN, in the particle size of SiO2 and in the processing pressure, whereas no significant change in the size of SiO2 particle was found. The surface area of BN increased by about 2.1 times by wet jet milling for only about 20 minutes (5 times).