by hearingearly hearingearly

Silicon Carbide Powder

Silicon carbide powder: So far, it has been proposed to combine a silicon source that is liquid at normal temperature (specifically, ethyl silicate), a carbon source that is liquid at normal temperature (specifically, phenolic resin), and a carbon source capable of dissolving carbon. A method of producing high-purity silicon carbide powder by mixing a source catalyst (specifically, maleic acid). Specifically, silicon carbide powder is produced by heating a mixture containing a silicon source, a carbon source, and a catalyst (for example, Patent Document 1).

When maleic acid is used as the catalyst, the sulfur content contained in the silicon carbide powder is lower than when toluenesulfonic acid is used as the catalyst. Therefore, the use of maleic acid as a catalyst ensures the production of silicon carbide powder suitable for use in the semiconductor field where sulfur is an impurity.

In addition, in order to produce silicon carbide powder with an average particle diameter of 100 to 200 μm, a technique of heating a mixture containing a silicon source, a carbon source, and a catalyst in two stages has also been proposed. Furthermore, it is also known that when the ratio between carbon contained in the carbon source and silicon contained in the silicon source (hereinafter, C/Si) is greater than 2.0 and less than 2.5, the amount of free carbon can be reduced.

As a result of in-depth research on silicon carbide powder, it has been found that there are many differences between the silicon source, the carbon source, and the catalyst from the three viewpoints of the reactivity between carbon and silicon, the amount of free carbon (FC), and the yield of silicon carbide powder. The optimal ranges of the three parameters of silicon source content, carbon source content and catalyst content in the mixture. https://hearingearly.com/silicon-carbide-powder/

Therefore, the silicon carbide powder can exhibit good results from the viewpoints of the reactivity between carbon and silicon, the amount of free carbon (FC), and the yield of the silicon carbide powder. According to the characteristics of the silicon carbide powder, in the mixture containing the silicon source, the carbon source and the catalyst, the silicon source is methyl silicate, and when the silicon carbide powder mixture is expressed by 100% by weight, the weight percentage of the carbon source is 33 The weight percentage of the silicon source is 55 weight % or more and 62 weight % or less, and the catalyst weight percentage is 3 weight % or more and 10 weight % or less.

When the silicon carbide powder mixture is expressed by 100% by weight, the weight percentage of the carbon source is 34.5% by weight or more and 38% by weight or less.

When the silicon carbide powder mixture is expressed by 100% by weight, the weight percentage of the silicon source is 57% by weight or more and 61% by weight or less.

When the silicon carbide powder mixture is expressed by 100% by weight, the weight percentage of the catalyst is 3% by weight or more and 8% by weight or less.

Actual effect:

Silicon carbide powder can exhibit good results from the viewpoints of reactivity between carbon and silicon, the amount of free carbon (FC), and the yield of silicon carbide powder.

In the silicon carbide powder according to this embodiment, in the mixture consisting of the silicon source, the carbon source and the catalyst, the silicon source is methyl silicate. When the mixture is expressed by 100% by weight, the weight percentage of the carbon source is 33% by weight or more and 39% by weight or less, the weight% of the silicon source is 55% by weight or more and 62% by weight or less, and the weight% of the catalyst is 3% by weight More than 10% by weight.

In this embodiment, because the three parameters of silicon carbide powder silicon source content, carbon source content and catalyst content are optimized in the mixture of silicon source, carbon source and catalyst, the reactivity between carbon and silicon, From the viewpoint of the amount of free carbon and the rate of silicon carbide powder, silicon carbide powder is good. The mixing process of silicon carbide powder is to mix a silicon source that is liquid at normal temperature, a carbon source that is liquid at normal temperature, and a catalyst (polymerization catalyst or cross-linking catalyst) that can dissolve the carbon source to form a mixture containing silicon source and carbon source. and catalyst mixture.

Examples of silicon sources for silicon carbide powder include methyl silicate (ie, tetramethoxysilane). As the silicon source, a monomer of methyl silicate may be used, or a polymer of methyl silicate (for example, a low molecular weight polymer (oligomer) of methyl silicate) may be used. Here, the term oligomer refers to a polymer with a degree of polymerization of approximately 2 to 15. As the methyl silicate, it is preferable to use one having a purity determined according to the use of the silicon carbide powder. When using high-purity methyl silicate, the initial impurity content of methyl silicate is preferably 20 ppm or less.

by hearingearly hearingearly

Full record of Chinese tea culture knowledge

Chinese tea has a long history, a variety of tea varieties, colorful, competing for beauty, like a hundred gardens in spring, so that thousands of mountains and rivers are especially enchanting.

Chinese tea culture is extensive and profound, in recent years, the more and more people explore tea culture, the knowledge of tea culture is numerous, then let’s take a look at the Chinese tea culture knowledge carefully recommended by Xiaobian for everyone, I hope to help you.

1. How did the word “tea” develop?

When humans first discovered the use of tea, they would give it a name, such as Shennong found that the leaves on the tea tree had eaten detoxification, and he called this tree “tea”. Before the Tang Dynasty, there were “tea”, “false”, “society”, “tea” and “masuyi”, which were unified into “tea” when Lu Yu wrote “Tea Classic” in the Tang Dynasty.

2. Who is the Tea Lord?

The tea saint is usually Lu Yu of the Tang Dynasty, who lived in a monastery from childhood and was brought up by an old monk. He has extensive and in-depth research on tea tree, tea and tea ceremony, and has written the world’s first tea monograph “Tea Classic”. In the book, Lu Yu introduced the origin, distribution, living conditions, planting, varieties, tea picking and tea making, introduced the relevant vessels in the book, and introduced how to boil tea, how to brew it, how to drink it, what water to use, and related stories. This was the first comprehensive and systematic description of tea. It has important guiding significance for the later tea research and even today’s tea research.

3. What is tea ceremony, tea art and tea culture?

Tea ceremony is about the truth of tea, tea can contain the truth; Tea art is the art of drinking tea, making tea, appreciating tea and interpreting tea; Tea culture takes tea as the carrier to spread, deduce and sublimate the national and local fine traditional culture. Whether tea ceremony, tea art, tea culture should have arisen in the Jin and Sui dynasties before the Tang Dynasty, and the later generations only developed and spread.

4. Who wrote the Great View of Tea?

Zhao Ji, Emperor Huizong of the late Northern Song Dynasty, was a foolish king, but he was a good artist. He was good at playing piano, playing chess, writing and painting. Planting tea, making tea, and drinking tea have been practiced, and then wrote a tea book, namely, “Grand View of Tea”.

Full record of Chinese tea culture knowledge0

5. Who is the Tea God?

Generally refers to Shennong, because Shennong is the representative of the ancient human in the legend, Shennong is the symbol of human discovery and use of tea tree.

6. Who is Cha Zu?

The brother nationalities in Yunnan regard Zhuge Liang as the tea ancestor in The Three Kingdoms, saying that Zhuge Liang distributed tea seeds to the multi-ethnic brothers along the way during the southern expedition, and tea trees, tea fields and tea mountains have flourished since then. Sichuan people regard Wu Lizhen of the Western Han Dynasty as the ancestor of tea, saying that he is the pioneer of tea planting. The tea trees he moved from Xianshan Mountain and planted on the top of Mengding Mountain are still here today, achieving the generation reputation of “water in the Yangtze River, tea on the top of Mengding Mountain”.

7. What does Cha Shou mean?

The tea word is divided into “twenty” and “eighty-eight”, twenty plus eighty-eight equals one hundred and eight, and the tea life is one hundred and eight years old.

Full record of Chinese tea culture knowledge0

8. What does “go for tea” mean?

According to legend, there was a monk named Congren in the Tang Dynasty, who often lived in Zhaozhou Guanyin Temple, known as Zhaozhou Ancient Buddha. Because of tea addiction, always say “eat tea to go” before each speech, and later this sentence “eat tea to go” became Zen Lin French.

9. What is the best tea couplet?

“Can clear the heart”, this is a poem.

In the Northern Song Dynasty, Su Shi wrote a couplet: Sit, please sit, please sit up; Tea, tea, fragrant tea.

There is also a “smoke lock pond willow” poetic and picturesque, the side implies gold, wood, water, fire, earth five elements, 400 years no one can be right, but by a professor of Peking University in their own tea room when the sudden inspiration to a “tea cooking wall spring”.

10. What is a tea table?

Tea table, table and attached tea set, flower arrangement, laying, environmental background, tea artistes wearing, etc.

11 Briefly describe the ancient Tea Horse Road.

The ancient tea Horse Road originated from the “tea horse trade” in the Tang and Song dynasties. People in the border areas of Kang and Tibet rely on beef and mutton as their staple food and need tea to break down fat and prevent dryness and heat. Large numbers of horses were needed for the inland campaign. Thus came the trade of tea and horses. The ancient Tea Horse Road is mainly divided into Yunnan-Tibet line and Sichuan-Tibet Line, in addition to a number of branch lines, extending outwards to West Asia, Central Asia, as far as Europe.

Full record of Chinese tea culture knowledge0

12 Why is the Opium War really a tea war?

In the 18th century, the world’s silver was flowing into China because of the tea trade, and the British trade with China was less than one-tenth of China’s exports, so the British decided to import opium to China. The opium trade brought great profits to Britain, which made China turn from a trade superpower into an import superpower, and a serious silver shortage occurred in China. The government has banned smoking. The smoking ban violated the interests of the United Kingdom, which triggered the Opium War between China and Britain.

13 Briefly describe the Boston Tea Party in the United States.

In 1773, the British government dumped the overstocked tea of the East India Company into the North American colonies, causing anger among the local people. More than 8,000 people gathered in Boston to protest, and more than 60 people dumped 342 chests of tea from an East India Company ship into the sea in what became known as the Boston Tea Party. The British military exerted pressure on the town, causing the people to revolt together, which led to the American Revolutionary War. On July 4, 1776, the United States of America was proclaimed.

14 How fermented is black tea? Health benefits? Water temperature? How to keep it?

Black tea is fully fermented tea; Tea mild, help gastrointestinal digestion, promote appetite, diuresis, eliminate edema, antibacterial, prevent viral cold, prevent tooth decay and food poisoning, reduce blood sugar value; Water temperature 80℃; Shelf life 36 months, room temperature storage.

15 The degree of fermentation of dark tea? Health benefits? Water temperature? How to keep it?

Dark tea is fully fermented tea (raw tea does not ferment); Anti-radiation, anti-cancer, help sober up, promote digestion, weight loss, delay aging, lower cholesterol, lower blood pressure, inhibit arteriosclerosis, and so on, to greasy; The water temperature is 95-100℃, the older the more fragrant, the room temperature storage.

Full record of Chinese tea culture knowledge0

16 The degree of fermentation of white tea? Health benefits? Water temperature? How to keep it?

White tea is slightly fermented tea; Decanting, clearing heat and moistening lung, flattening liver and benefiting blood, anti-inflammatory and detoxifying, reducing blood pressure and fat,

Eliminate fatigue, etc.; Water temperature 80-90 ℃; The shelf life is more fragrant, one year tea, three years medicine, seven years treasure, room temperature storage.

17 The degree of fermentation of yellow tea? Health benefits? Water temperature? How to keep it?

Yellow tea is light fermented tea; Refresh the mind, digestion and stagnation, on indigestion, loss of appetite, lazy movement and obesity have a certain effect; Water temperature 80-90 ℃; Shelf life 3-6 months, refrigerated storage.

18 What are the types of reprocessed tea?

Scented tea: tea + flower, jasmine tea, rose tea, chrysanthemum tea, osmanthus tea, etc.

Fruit tea: tea + fruit, lychee tea, lemon tea, citrus tea, hawthorn tea, etc.

Extraction of tea: Using tea as raw material, extracting soluble matter in tea with hot water, filtering to remove tea residue.

Health tea: tea brewed with herbs or ingredients, such as burdock tea, ganoderma tea, buckwheat tea, etc.

Full record of Chinese tea culture knowledge0

19 Briefly describe the mother tree of Da Hongpao

There are 6 Dahongpao mother trees, which are of shrub type. The leaf quality is thicker, the bud head is red, when the sun shines on the tea tree and the rock, the rock reflects the light, and the tea tree is bright red like fire, if the red robe covers the tree, so the name “Da Hong robe”. Dahongpao, iron arhat, white rooster’s comb and water golden turtle together called Wuyi rock tea four clusters.

20 Brief description of Oriental beauty

Oriental beauty tea originated in Hsinchu, Taiwan, heavily fermented oolong tea, tea heart has a thick crystal fluffiness, was sucked by Ye Chan, the taste is strong and sweet, and with the aroma of ripe fruit and honey, according to the British Queen after tasting, gave the name “Oriental beauty”. Heyuan purple gold also produces Oriental beauty.

kinds of tea, tea drinking is not equal to having a tea culture, is only a prerequisite for the formation of tea culture, but also must have the participation of scholars and cultural connotation. The Classic of Tea, written by Lu Yu in the Tang Dynasty, systematically summarized the experience of tea production and drinking in the Tang Dynasty and before, and put forward the spirit of tea ceremony of fine practice and frugality. A group of intellectuals such as Lu Yu and Jiao Ran attach great importance to the spiritual enjoyment and moral standards of tea, pay attention to tea drinking utensils, tea drinking water and tea cooking art, and blend with the philosophical thoughts of Confucianism, Taoism and Buddhism, and gradually make people enter their spiritual field. In the process of drinking tea, some scholars and literati also created a lot of tea poems. In the Poems of the Whole Tang Dynasty alone, more than 400 poems of more than 100 poets have been handed down so far, thus laying the foundation of the Han tea culture.

Full record of Chinese tea culture knowledge0

Tea is a plant, edible, toxic, long easy health, longevity, tea is the best, can also be used for medicine, so there is a tea is the essence of heaven and earth, shun is the fundamental of life. Therefore, there is tea in Taoism as a tea product.

Han people drink tea, pay attention to a “product” word. When guests arrive, the etiquette of making and serving tea is essential. When there are visitors to visit, you can ask for advice, choose the most suitable guest taste and the best tea set to welcome guests. When offering tea to guests, it is also necessary to mix tea appropriately. When the host accompanies the guests to drink tea, it is necessary to pay attention to the residual amount of tea in the guests’ cups and POTS. Generally, tea is made in teacup. If half of the tea has been drunk, it is necessary to add boiling water and add it with drinking, so that the concentration of tea is basically consistent and the water temperature is suitable. When drinking tea, you can also appropriately add tea, candy, dishes, etc., to adjust the taste and snack effect.

Chinese tea culture is extensive and profound, in recent years, the more and more people explore tea culture, tea culture knowledge is large, I hope to help you.