SiC Platelets Synthesized by Powder-Heating Technique

2007 ◽  
Vol 336-338 ◽  
pp. 939-941
Author(s):  
Yong Qiang Meng ◽  
Zhi Min Bai ◽  
Chang Hong Dai ◽  
Bao Bao Zhang
Keyword(s):  
Silicon Carbide ◽  
Reaction Time ◽  
Carbon Black ◽  
Raw Materials ◽  
Low Cost ◽  
Average Diameter ◽  
New Method ◽  
Conventional Heating ◽  
High Yield ◽  
Sio2 Powder

A new method for producing silicon carbide platelets with low cost and high yield was introduced. The silicon carbide platelets were synthesized by powder-heating techniques with carbon black and SiO2 powder as raw materials and CoCl2 as catalyst. The starting mixtures were heated at a temperature in the range of 1800-2000°C for the duration of about 2-4h to produce substantially completely unagglomerated silicon carbide platelets with a thickness of 5-20μm and the average diameter of 50-200μm. Compared to the conventional heating, the powder-heating technique is advantageous of less investment on equipment, easy to manufacture and convenient to operate. Furthermore, it is very suitable for realizing the scaled production because of the lower synthesizing temperature, shorter reaction time and greater output.

Synthesis of Silicon Carbide Platelets by Double-Heating Technique

2008 ◽  
Vol 368-372 ◽  
pp. 824-826 ◽  
Author(s):  
Yong Qiang Meng ◽  
Chang Hong Dai ◽  
Zu Wei Song
Keyword(s):  
Silicon Carbide ◽  
Reaction Time ◽  
Carbon Black ◽  
Raw Materials ◽  
Low Cost ◽  
Average Diameter ◽  
Conventional Heating ◽  
High Yield ◽  
Heating Mechanism ◽  
Sio2 Powder

A new method for producing silicon carbide platelets with low cost and high yield was introduced. The silicon carbide platelets were synthesized by double-heating technique with carbon black and SiO2 powder as raw materials without using any catalysts. The starting mixtures were heated at a temperature in the range of 1800-2000°C for the duration of about 2-4h to produce substantially completely unagglomerated silicon carbide platelets with the thickness of 5-15μm and the average diameter of 50-150μm. Compared to the conventional heating, double-heating technique has different heating mechanism and has advantages of less investment for equipment, easy to manufacture and convenient to operate. Furthermore, it is very suitable for realizing the scaled production because of the lower synthesizing temperature, shorter reaction time and greater output.

Silicon Carbide Whiskers Synthesized by Double-Heating Technique

2007 ◽  
Vol 336-338 ◽  
pp. 1294-1296
Author(s):  
Ru Zhao ◽  
Chang Hong Dai ◽  
Yi Cui ◽  
Zu Wei Song
Keyword(s):  
Silicon Carbide ◽  
Activated Carbon ◽  
Reaction Time ◽  
Low Cost ◽  
Average Diameter ◽  
Raw Material ◽  
Conventional Heating ◽  
Silicon Carbide Whiskers ◽  
A New Technique ◽  
Lower Temperature

A new technique of mass-producing silicon carbide whiskers at a low cost is introduced in this paper. Silicon carbide whiskers are synthesized by double-heating technique with the activated carbon and silica gel as raw material and CoCl2 as catalyst. The results indicate that the silicon carbide whiskers with the average diameter of 0.2μm, length of 10-50μm and high content of 81% can be obtained at a lower temperature of 1300°C and a shorter time of 1.5h. Compared with the conventional heating, the double-heating technique is suitable for realizing the scaled production because of the lower whiskerssynthesizing temperature, shorter reaction time and greater output.

Visible Light Assisted Hantzsch Reaction: Synthesis of Polycyclic Dihydropyridines

2019 ◽  
Vol 16 (8) ◽  
pp. 676-682
Author(s):  
Ankusab Noorahmadsab Nadaf ◽  
Kalegowda Shivashankar
Keyword(s):  
Reaction Time ◽  
Light Intensity ◽  
Ammonium Acetate ◽  
Low Cost ◽  
Aromatic Aldehydes ◽  
Light Irradiation ◽  
High Yield ◽  
Short Reaction Time ◽  
Green Protocol ◽  
Dihydropyridine Derivatives

The polycyclic dihydropyridine nucleus represents the heterocyclic system of invaluable core motifs with wide applications in chemical, biological and physical properties. Although this kind of compounds have been extensively synthesized by other groups, the synthesis of these compounds under CFL light intensity were not explored. The synthesis of polycyclic dihydropyridine derivatives were achieved through the reaction of 4-hydroxycoumarin, aromatic aldehydes and ammonium acetate under CFL light irradiation conditions. A series of polycyclic dihydropyridine derivatives were prepared under CFL light irradiation conditions with high yield, short reaction time, ambient condition and without the use of catalyst. The results displayed an efficient method for the synthesis of polycyclic dihydropyridine derivatives. Clean profile, short reaction time, low cost and use of CFL light intensity instead of catalyst making it a genuinely green protocol.

scholarly journals Design of Low-Cost and High-Strength Titanium Alloys Using Pseudo-Spinodal Mechanism through Diffusion Couple Technology and CALPHAD

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2910
Author(s):  
Chaoyi Ding ◽  
Chun Liu ◽  
Ligang Zhang ◽  
Di Wu ◽  
Libin Liu
Keyword(s):  
Diffusion Couple ◽  
Titanium Alloys ◽  
High Throughput ◽  
Volume Fraction ◽  
Raw Materials ◽  
Low Cost ◽  
High Strength ◽  
High Yield ◽  
Α Phase ◽  
Cr System

The high cost of development and raw materials have been obstacles to the widespread use of titanium alloys. In the present study, the high-throughput experimental method of diffusion couple combined with CALPHAD calculation was used to design and prepare the low-cost and high-strength Ti-Al-Cr system titanium alloy. The results showed that ultra-fine α phase was obtained in Ti-6Al-10.9Cr alloy designed through the pseudo-spinodal mechanism, and it has a high yield strength of 1437 ± 7 MPa. Furthermore, application of the 3D strength model of Ti-6Al-xCr alloy showed that the strength of the alloy depended on the volume fraction and thickness of the α phase. The large number of α/β interfaces produced by ultra-fine α phase greatly improved the strength of the alloy but limited its ductility. Thus, we have demonstrated that the pseudo-spinodal mechanism combined with high-throughput diffusion couple technology and CALPHAD was an efficient method to design low-cost and high-strength titanium alloys.

scholarly journals Voltammetric Evaluation of Diclofenac Tablets Samples through Carbon Black-Based Electrodes

2019 ◽  
Vol 12 (2) ◽  
pp. 83 ◽  
Author(s):  
Carlos Eduardo Peixoto da Cunha ◽  
Edson Silvio Batista Rodrigues ◽  
Morgana Fernandes Alecrim ◽  
Douglas Vieira Thomaz ◽  
Isaac Yves Lopes Macêdo ◽  
...  
Keyword(s):  
Carbon Black ◽  
Raw Materials ◽  
Low Cost ◽  
Good Recovery ◽  
Electroanalytical Methods ◽  
Graphite Electrodes ◽  
Pharmaceutical Samples ◽  
Analytical Potential ◽  
The World ◽  
Interesting Alternative

Diclofenac (DIC) is a non-steroidal anti-inflammatory drug of wide use around the world. Electroanalytical methods display a high analytical potential for application in pharmaceutical samples but the drawbacks concerning electrode fouling and reproducibility are of major concern. Henceforth, the aim of this work was to propose the use of alternative low-cost carbon black (CB) and ionic liquid (IL) matrix to modify the surface of pencil graphite electrodes (PGE) in order to quantify DIC in raw materials, intermediates, and final products, as well as in stability assays of tablets. The proposed method using CB+IL/PGE displayed good recovery (99.4%) as well as limits of detection (LOD) of 0.08 µmol L-1 and limits of quantification (LOQ) of 0.28 µmol L−1. CB+IL/PGE response was five times greater than the unmodified PGE. CB+IL-PGE stands as an interesting alternative for DIC assessment in different pharmaceutical samples.

A high-yield microwave heating method for the preparation of (phthalocyaninato)bis(chloro)silicon(IV)

2001 ◽  
Vol 05 (04) ◽  
pp. 376-380 ◽  
Author(s):  
DOMINIC A. DAVIES ◽  
CHRISTINA SCHNIK ◽  
JACK SILVER ◽  
JOSE L. SOSA-SANCHEZ ◽  
PHILIP G. RIBY
Keyword(s):  
Reaction Time ◽  
Microwave Heating ◽  
Silicon Tetrachloride ◽  
Conventional Heating ◽  
High Yield ◽  
Thermal Heating ◽  
Heating Method ◽  
Purification Time

The microwave heating synthesis of (phthalocyaninato)bis(chloro)silicon(IV) prepared from diiminoisoindolene and silicon tetrachloride in quinoline has been shown to be rapid (5 min reaction time compared to 30 min with thermal heating) and results in a high yield (91% compared to 71% using thermal heating). A modified microwave ashing furnace was used to heat the reaction mixture. The high yield has led to a reduction in the purification time to 1 h (compared to 4 h or more using conventional heating).

scholarly journals Amberlite IR-120 Catalyzed Green and Efficient One-Pot Synthesis of Benzylpyrazolyl Coumarin in Aqueous Medium

2021 ◽  
Vol 10 (3) ◽  
pp. 2525-2534
Keyword(s):  
Reaction Time ◽  
Aqueous Medium ◽  
Ethyl Acetoacetate ◽  
Low Cost ◽  
Cost Effective ◽  
High Yield ◽  
Phenyl Hydrazine ◽  
One Pot ◽  
Time Operation ◽  
Effective Synthesis

An efficient, green, and cost-effective synthesis of benzylpyrazolyl coumarin by one-pot four-component condensation of hydrazine hydrate or phenyl hydrazine, ethyl acetoacetate, aromatic aldehyde, and 4-hydroxycoumarin in the presence of Amberlite IR-120 as a catalyst in an aqueous medium has been reported. Shorter reaction time, operation simplicity, low cost of catalyst, and aqueous medium are key advantages of this method for synthesizing benzylpyrazolyl coumarin in moderate to high yield.

Phosphomolybdic Acid (PMA)-catalyzed One-pot Synthesis of 2,3- Dihydroquinazolines

2019 ◽  
Vol 16 (8) ◽  
pp. 683-687
Author(s):  
Chuanhuan Chen ◽  
A. Xuejiao ◽  
Xia Li ◽  
Guoli Huang ◽  
Bo Liu
Keyword(s):  
Reaction Time ◽  
Present Method ◽  
Room Temperature ◽  
Phosphomolybdic Acid ◽  
New Method ◽  
High Yield ◽  
One Pot ◽  
Short Reaction Time ◽  
One Pot Synthesis

We have developed a new method for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones in good to excellent yields via phosphomolybdic acid (PMA)-catalyzed cyclocondensation of 2- aminobenzamides with aldehydes or ketones in N,N-dimethylformamide (DMF) at room temperature. The present method proves to be efficient in terms of short reaction time, high yield, simple workup and easy purification.

Synthesis of Silicon Carbide Whiskers in Electric Field Furnace

2008 ◽  
Vol 368-372 ◽  
pp. 831-833
Author(s):  
Chang Hong Dai ◽  
Zu Wei Song ◽  
Ru Zhao
Keyword(s):  
Activation Energy ◽  
Silicon Carbide ◽  
Carbon Black ◽  
Electric Field ◽  
Influencing Factors ◽  
High Voltage ◽  
Raw Materials ◽  
Silicon Carbide Whiskers ◽  
Sic Whiskers ◽  
Reaction Speed

A new heating apparatus for synthesizing SiC whiskers was introduced. SiC whiskers were synthesized in electric field furnace with carbon black and SiO2 powders as raw materials and some influencing factors were discussed. SiC whiskers with diameter of 0.1-0.4μm, length of 5-70μm and average purity of 99.6% were acquired at lower temperatures of 1200-1400°C for a shorter holding time of 2-4h. The results showed that the high voltage field has great catalysis action on synthetic of SiC whiskers by reducing activation energy and enhancing reaction speed.

The Influence of Hot Pressing Temperatures in Needle Punching Nonwoven

2014 ◽  
Vol 910 ◽  
pp. 279-282 ◽  
Author(s):  
Ching Wen Lou ◽  
Ya Lan Hsing ◽  
Wen Hao Hsing ◽  
Jia Horng Lin
Keyword(s):  
Hot Pressing ◽  
Textile Industry ◽  
Raw Materials ◽  
Low Cost ◽  
Fiber Material ◽  
Air Permeability ◽  
Polyester Fiber ◽  
Woven Fabric ◽  
High Yield ◽  
Pressing Temperature

Non-woven textile industry in an emerging field, with the process short, high yield, low cost and wide source of raw materials, but also has excellent performance of many functions on, making non-woven over the past half century gained textiles attention and consumers of all ages. The proportion of the world of non-woven fiber material used in the product, 85% in rayon ,and the other 15% in natural fibers, polyester fibers which accounted for the largest proportion of use. The experiment uses a low melting point polyester fiber (LPET) 20%, three-dimensional hollow curly polyester fiber (TPET) and recycled far infrared fiber (REPET) 40% each as the basic conditions change pressing temperature 100 °C-140 °C, in order to observe and compare the effects of temperature on the non-woven fabric, this experiment tests including air permeability, tensile strength testing, infrared testing and SEM, respectively in different hot pressing temperature, each of the non-woven hot pressing temperatures sample go through microscopic to analysis for non-woven with the hot temperatures strong reason to improve or decline with hot temperature of air permeability.

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