Experimental Study of the Silicon Start-up Heating and Melting Process in an Inductive Cold Crucible

2010 ◽  
Vol 154-155 ◽  
pp. 756-762 ◽  
Author(s):  
Feng Huang ◽  
Rui Run Chen ◽  
Jing Jie Guo ◽  
Hong Sheng Ding
Keyword(s):  
Room Temperature ◽  
Melting Process ◽  
Electrical Performance ◽  
Central Position ◽  
Affecting Factors ◽  
Experimental Procedure ◽  
Start Up ◽  
Higher Power ◽  
Melting Operation ◽  
Growth Technology

The electromagnetic continuous pulling is a newly growth technology as a promising process for silicon preparation, start-up heating is necessary for the semiconductivity of silicon at room temperature. Investigations were carried out to study this process in a square crucible with the frequency of 50kHz, details of the experimental procedure were given, the affecting factors, electrical performance and heat explosion problems during the process were measured and discussed. The results indicated that the best conditions for the preheating were the central position of the base in the coil, the higher power and the proper primary mass of silicon setting. The electrical performance indirectly showed the pool conditions and so it can be effectively used to control the melting operation.

Thermo-Optical Properties of Perfluorinated Sulfonic Acid Membranes: An Investigation of Hydration Based on Absorption Spectra

2017 ◽  
Vol 71 (11) ◽  
pp. 2504-2511 ◽  
Author(s):  
Daniele T. Dias ◽  
Guy Lopes ◽  
Tales Ferreira ◽  
Ivanir L. Oliveira ◽  
Caroline D. Rosa
Keyword(s):  
Sulfonic Acid ◽  
Room Temperature ◽  
Water Retention ◽  
Structural Changes ◽  
Optical Characterization ◽  
Scanning Calorimetry ◽  
Experimental Procedure ◽  
Nafion Membranes ◽  
Perfluorinated Sulfonic Acid

The Nafion membranes are widely used in electrochemical applications such as fuel cells, chlor-alkali cells, and actuators–sensors. In this work, the thermal-optical characterization of Nafion in acid form was performed by photoacoustic spectroscopy, thermogravimetry, and differential scanning calorimetry. In the experimental procedure three distinct hydration levels were considered: (1) pristine membrane (λ ≅ H2O/–SO3H ≅ 5.6); (2) swelling process (λ ≅ 17.4); and (3) drying at controlled room temperature after swelling process (λ ≅ 6.5). The discovered behaviors showed significant irreversible structural changes induced by water retention in the membrane. These structural changes depend on the water population present in the clusters and also affect the directional thermal diffusivity of the membrane irreversibly.

Microstructure and wear resistance of Cuss-toughened Cr5Si3/CrSi metal silicide alloys

2005 ◽  
Vol 20 (5) ◽  
pp. 1122-1130 ◽  
Author(s):  
Y.X. Yin ◽  
H.M. Wang
Keyword(s):  
Solid Solution ◽  
Wear Resistance ◽  
Sliding Wear ◽  
Room Temperature ◽  
Wear Test ◽  
Melting Process ◽  
Dry Sliding Wear ◽  
Metal Silicide ◽  
X Ray Diffraction ◽  
X Ray

Wear-resistant Cu-based solid-solution-toughened Cr5Si3/CrSi metal silicide alloy with a microstructure consisting of predominantly the dual-phase primary dendrites with a Cr5Si3 core encapsulated by CrSi phase and a small amount of interdendritic Cu-based solid solution (Cuss) was designed and fabricated by the laser melting process using Cr–Si–Cu elemental powder blends as the precursor materials. The microstructure of the Cuss-toughened Cr5Si3/CrSi metal silicide alloy was characterized by optical microscopy, powder x-ray diffraction, and energy dispersive spectroscopy. The Cuss-toughened silicide alloys have excellent wear resistance and low coefficient of friction under room temperature dry sliding wear test conditions with hardened 0.45% C carbon steel as the sliding–mating counterpart.

TECHNOGENIC IMPACT OF RADIOACTIVE CONTAMINATION OF METAL SMELTING PRODUCTS ON ENVIRONMENT AND POPULATION

2021 ◽  
Vol 1 (1) ◽  
pp. 3-13
Author(s):  
VALUEV N.P. ◽  
◽  
MASHINTSOV E.A. ◽  
YUDANOV P.M. ◽  
◽  
...  
Keyword(s):  
Blast Furnace ◽  
Natural Radionuclides ◽  
Melting Process ◽  
Steelmaking Furnace ◽  
External Irradiation ◽  
High Radiation ◽  
Furnace Process ◽  
Dust Fraction ◽  
Melting Operation ◽  
Settling Process

The analysis of the distribution of radionuclides in the products of blast furnace and steelmaking melting operation processes is carried out. It was shown that the blast furnace melting process is considerably affected by natural radionuclides whereas steelmaking furnace process - by technogenic ones. The main impact on the environment is exerted by the gas-dust fraction, which contaminates the surrounding soil, vegetation and ground water during the settling process. An additional dose of external irradiation of the population and personnel is created by slag and metal fractions. High radiation doses are possible in case of ingestion of high-intensity sources of 60Co and 137Cs into the melt. Internal irradiation of people occurs due to gas and dust emissions.

Effect of MEAs Preparation Procedure on Their Performance in Room Temperature DMFC

2010 ◽  
Author(s):  
Evgeniy N. Gribov ◽  
Ivan M. Krivobokov ◽  
Aleksey G. Okunev
Keyword(s):  
Cyclic Voltammetry ◽  
Impedance Spectroscopy ◽  
Power Density ◽  
Room Temperature ◽  
Carbon Paper ◽  
Higher Power ◽  
Ptru Catalysts ◽  
Coated Carbon ◽  
Preparation Techniques ◽  
Coated Membrane

In this work the effect of the MEA preparation techniques on the performance of DMFC was evaluated using three different methods of electrocatalyst deposition: i) catalyst coated membrane; ii) catalyst coated carbon paper; and iii) decal deposition. Optimization of the nafion content (5–15 wt. %) at anode and cathode sides of the MEA and the pressure (150–500 atm) were also performed. Activities of both supported and unsupported Pt and PtRu catalysts (Johnson Matthew) were compared in room temperature DMFC (RT-DMFC) using polarization curves. All MEAs prepared were also characterized by electrochemical (cyclic voltammetry, impedance spectroscopy) methods. It was shown that optimal nafion content is 5–10 wt. % at both anode and cathode sides, while the optimal pressure is in the 300–500 atm. range. The unsupported catalysts showed slightly higher power density at RT-DMFC (∼ 14 mW/cm2) as compared to the supported ones (∼10 mW/cm2) at the same Pt load. Variation of the wetness of MEAs upon mounting in DMFC allowed us to increase of the power density of RT-DMFC up to 32 mW/cm2.

Start-up and Steady Operation of Shortcut Nitrification System to Treat Wastewater

2012 ◽  
Vol 610-613 ◽  
pp. 1760-1763
Author(s):  
Li Xu ◽  
Xue Wu ◽  
Ming Fen Niu ◽  
Si Li ◽  
Hong Jing Jiao ◽  
...  
Keyword(s):  
Short Range ◽  
Room Temperature ◽  
Ammonia Concentration ◽  
Experimental Temperature ◽  
Nitrifying Bacteria ◽  
Stable Operation ◽  
High Concentration ◽  
Nitrogen And Phosphorus ◽  
Start Up ◽  
The Stability

The purpose of this paper is to obtain a start-up of short-cut nitrification systems to treat wastewater with high concentration of nitrogen and phosphorus under laboratory conditions. By starting the nitrification system at room temperature we can achieve the effective accumulation of nitrifying bacteria. Then by increasing experimental temperature and pH, and increasing the concentration of nitrogen and phosphorus in influent, to inhibit the growth of NOB in the systems and promote the accumulation of AOB. So we can make the effluent have a higher concentration of NO2--N. In the stable operation stage we can constantly improve ammonia concentration in the influent, to observe the stability of the each indicators of effluent. This experiment showed that the wastewater with high concentration of nitrogen and phosphorus can better promote the accumulation of AOB, to achieve the effect of short-range nitrification.

Facile and direct synthesis of symmetrical acid anhydrides using a newly prepared powerful and efficient mixed reagent

2015 ◽  
Vol 69 (3) ◽  
Author(s):  
Hamed Rouhi-Saadabad ◽  
Batool Akhlaghinia
Keyword(s):  
Carboxylic Acids ◽  
Room Temperature ◽  
Low Cost ◽  
Direct Synthesis ◽  
Reaction Conditions ◽  
Experimental Procedure ◽  
Short Reaction Time ◽  
Acid Anhydrides ◽  
Work Up ◽  
Trichloroisocyanuric Acid

AbstractAn efficient mixed reagent for direct synthesis of symmetrical carboxylic anhydrides from carboxylic acids has been prepared. Carboxylic acids are converted to anhydrides using triphenylphosphine/ trichloroisocyanuric acid under mild reaction conditions at room temperature. Short reaction time, excellent yields of products, low cost, availability of reagents, simple experimental procedure, and easy work-up of the products are the main advantages of the presented method.

The Ion Structure of NiFe2O4-10NiO-Based Cermet Anode in the Electrolyte

2018 ◽  
Vol 921 ◽  
pp. 119-127 ◽  
Author(s):  
Yuan Wang ◽  
Han Bing He
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Molten Salts ◽  
Large Scale ◽  
Room Temperature ◽  
Aluminum Electrolysis ◽  
Melting Process ◽  
Ion Structure ◽  
Inert Anodes ◽  
Complex Ion

The problem in the large-scale industrialization for aluminum electrolysis is the corrosion resistance of cermet inert anodes in high temperature molten salts. In this paper, the ion structure of NiFe2O4-10NiO-based cermet anode composition in the electrolyte was investigated. The experiment results show that Al-F and Al-O-F complex ion structures are produced at room temperature and perhaps Me-F (Me=Ni, Cu, Fe), Me-O-F or Me-Al-O-F are also formed. Moreover, Al-F and Al-O-F ion structures exist from room temperature to 700 °C and from 1050 °C to 1200 °C; In the rearrangement and melting process of molten salt at 800 °C -1000 °C, the ionic structures are mainly Al-O-F ions; Me-F and Me-O-F ion structures were not found at high temperature, this indicates that Al in Al-O-F complex ion structures is partially replaced by Fe, Ni or Cu to form MexAlaOyFz(z+2y-2x-3a)-.

A Mechanical Material Model for Aluminium Extrusions During On-line Quenching

1996 ◽  
Vol 118 (1) ◽  
pp. 114-119 ◽  
Author(s):  
Niklas Ja¨rvstra˚t ◽  
Stig Tjo̸tta
Keyword(s):  
Mechanical Behaviour ◽  
Room Temperature ◽  
Material Model ◽  
Load History ◽  
Single Test ◽  
Experimental Procedure ◽  
Material Parameters ◽  
Continuous Cooling ◽  
Tension And Compression ◽  
On Line

A material model is suggested, suitable for modelling the mechanical behaviour of aluminium sections, from directly after the extrusion and throughout the on-line quenching to room temperature. An experimental procedure is detailed, whereby all material parameters in the model can be determined by a single test. In the test, the specimen is subjected to a carefully prescribed load history in tension and compression during continuous cooling. Material parameters are determined for the AIMgSi alloy AA6060. Finally, the model is compared with conventional plasticity and viscoplasticity, and found to give much better accuracy.

The Effect of Power Supply of LED Lamp

2014 ◽  
Vol 548-549 ◽  
pp. 880-884
Author(s):  
Patiphan Kerdlap
Keyword(s):  
Power Supply ◽  
Electrical Energy ◽  
Buck Converter ◽  
Electrical Performance ◽  
Switching Power Supply ◽  
Rectifier Circuit ◽  
Switching Power ◽  
Full Wave ◽  
Higher Power ◽  
Lower Effect

This paper presents the effect of power supply of LED lamp for external lighting are compares with electrical performance, electrical energy saving, illuminance, and the effect of harmonics noise from each power supplies on external lighting with LED. By designing and construct a linear power supply by the full wave rectifier circuit by bridge diode type and switching power supply by buck converter. The result that, the full wave rectifier circuit by bridge diode type was consumed higher power less than buck converter but lower effect of harmonics noise. In additional, as a result will be important data to the education develops and the next research.

scholarly journals Production of Nanopowders of Metal Oxides Using Pulsed Electron Beam in Low Pressure Gas

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
S. Yu. Sokovnin ◽  
V. G. Il'ves
Keyword(s):  
Electron Beam ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Low Pressure ◽  
Electron Gun ◽  
Specific Power ◽  
Large Area ◽  
Pulsed Electron Beam ◽  
Higher Power ◽  
Characteristic Particle

The installation for production of metal oxide nanopowders was created. The method involves evaporation of the target by a pulsed-electron beam, condensation of the vapors of the material in a low-pressure gas, and deposition of nanopowders on a cold large-area crystallizer. In a new installation, a higher-power electron gun with a hollow cathode, which ensures the formation of the current pulse of the electron beam with amplitude up to 1 A and a duration of 100 μs, and a crystallizer of a larger diameter (0.3 m) and length (0.5 m), which makes it possible to decrease the agglomeration, were used. The results of the evaporation of targets made of YSZ, CeGdOx, Zn-ZnO, Al2O3, and ZnO were presented. Room-temperature ferromagnetism has been observed in YSZ, Zn-ZnO, and Cu(Al)-doped Al2O3. The proposed method makes it possible to obtain nanopowders of oxides with a characteristic particle size of 3–5 nm and agglomerates consisting of them 20–600 nm in size, specific surfaces of up 338 m2/g, productivity of up to 12 g/h, and a specific power consumption ≥112 (W h)/g.

Sign in / Sign up

Export Citation Format

Share Document