My system is not decent

The meaning of this poem is not difficult to understand, but through this poem, Qianlong successfully transferred the cat food bowl incident and raised it to the issue of gratitude.

Later, in order to further expand its influence, Qianlong not only announced this poem to the world.

Emperor Qianlong also specially made a base out of red sandalwood for this former cat food bowl, and placed it in a conspicuous position in the palace.

From then on, every courtier who passed by saw this azure narcissus basin without patterns, and had to think about whether he was loyal to the emperor and whether he was grateful to the emperor.

Failure is also because there is no film opening, and success is also because there is no film opening.

People's measure of value changes wonderfully over time.

Perhaps it is in response to the poem of the great poet Li Bai-I am born with talents that will be useful.

The hundreds of years of waiting for the Tianqing Wuwen Narcissus Basin is absolutely justified.

That truth may be inconspicuous, or else, it may have long been lost in the long river of history because of the scramble between you and me.

Of course, it is only an exception. Among Ru kiln porcelains in the Song Dynasty, cracked porcelains were still the main ones.

The reasons for the cracking of these porcelain pieces are very complicated, related to the carcass, enamel, glaze layer and firing process, and change due to the accumulation of time.

The naming of folios is usually divided according to different standards in terms of appearance.

It is named according to the grain, shape, depth, thickness, density and other characteristics of the grain.

Divided according to the orientation of the slices in the glaze layer, the slices of Ru porcelain include straight slices and oblique slices.

Ice cracks and grid patterns belong to straight open sheets, while fish scale patterns belong to oblique open sheets.

When forming a straight sheet, the coefficient of thermal expansion of the glaze is greater than that of the tire.

During the cooling process, the glaze shrinks faster than the tire, and the glaze layer is subjected to tensile stress.

When the porcelain glaze layer is cooled to completely hardened, it loses its elasticity. If the tensile stress intensity it receives exceeds its tensile strength, the glaze layer will produce long and thick straight open pieces.

The generation of large openings weakens the tensile stress on the glaze layer.

But between the partial tire glaze, there is still residual tensile stress.

This stress, which is not enough to produce large open pieces, will be gradually released after a long period of time after leaving the kiln, resulting in short and thin small straight open pieces.

The main feature of the oblique film is that its shape and appearance will change with the change of the incident light direction, and its formation mechanism is more complicated than that of the straight film.

According to the observation of the section, the oblique opening separates the glaze layer, and the angle between the opening and the carcass is quite different.

When light shines on the opening at a certain angle, the border on one side of the opening is almost transparent, showing an initial three-dimensional effect.

The polygonal slices similar to fish scales formed by the superposition of multiple oblique slices are called "fish scale patterns".

The oblique slices are related to the thickness of the glaze layer. The thickness of the glaze layer of Ruguan enamel is between 0.5-0.8mm, and there will be occasional oblique slices.

In the range of porcelain formation, the probability of oblique opening is proportional to the thickness of the glaze layer.

From the point of view of the production mechanism, the degree of vitrification of the glaze that produces oblique slices is relatively high, and the firing temperature may be slightly higher.During the cooling down process,

Between the glazes, due to the different coefficients of thermal expansion, stress is generated, which is different from the straight split, which contributes to the stress generated by the oblique split. In addition to the dominant tensile stress, there is also compressive stress.

That is, at a certain stage in the cooling process, the shrinkage speed of the tire is slightly greater than the shrinkage speed of the glaze layer, causing the stress of the glaze layer to sink.

Thus, in the gap between the straight-opening pieces produced by the tensile stress, smaller obliquely-opening pieces are produced.

By observing the oblique slices on the surface of the porcelain pieces unearthed from the Ru kiln site, the gaps of most of the oblique slices are extremely clean, and no stains have penetrated.

In the straight-opening piece adjacent to it, there are stains hidden.

From this, it can be inferred that the oblique slices were most likely produced during the burial process over a long period of time.

Unfortunately, there is no relevant quantitative analysis of the mechanics.

Uncovering the formation conditions of oblique slices needs more related research in the future.

In fact, if you are not specialized in making Ru kilns, or other porcelains from kilns of the Song Dynasty, you generally don’t need to pay special attention to opening pieces.

Because of modern porcelain, it is rare to specialize in opening patterns.

This is actually a kind of progress. In fact, since the invention of low-temperature glaze for firing porcelain, whether it is porcelain production or firing technology, it has been constantly developing.

At the beginning, it was only glazed and then fired in the kiln. If other glaze colors were accidentally fired, it would be considered a kiln change.

With the improvement of porcelain making and kiln technology, the process has become more and more complicated.

Afterwards, various types of porcelain appeared, and this series of porcelain continued to improve, leading to modern porcelain.

For example, starting from low-temperature glaze, and then discovering the change of glaze color, porcelain has entered the era of colored glaze since then.

At this time, it is made by applying low-temperature colored glaze on the fired white glaze ware, and then firing it in a kiln at low temperature.

The utensils fired by this method are mainly green monochromatic glaze utensils, and a small amount of yellow glaze utensils, and very few multi-colored utensils.

Because it is colored glaze on white glazed porcelain, it can be clearly called low-temperature glazed porcelain.

This kind of porcelain was generally produced in the late Northern Song Dynasty. It was first created in Cizhou kiln, and later it was also produced in Ding kiln and other kilns. The most popular period was the Jin Dynasty.

This kind of low-temperature glazed porcelain has two characteristics.

First, there may have been various decorations due to the white-glazed porcelain fired for the first time.

Such as scratching, engraving, picking, printing and black color painting.

Therefore, the fired color glaze utensils also have corresponding decorations.

Such as green glaze scratches, green glaze pick flowers, green glaze black pick flowers, green glaze black flowers, etc., and so on.

All the decorations on white-glazed objects can be used as decorations on green-glazed or yellow-glazed objects.

Because the white-glazed porcelain fired for the first time has a smooth glaze surface and a pure white glaze color, the colored glaze is often thinner after firing low-temperature green-glazed wares.

And because of the whiteness of the background, the color of the green glaze is light and bright against the background, often emerald green, very beautiful.

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Of course, when excavating Cizhou Kiln, many white-glazed porcelains prepared for green glaze were found, and the temperature was deliberately lowered when firing for the first time.

This makes the first firing of white-glazed porcelain raw, the purpose is to make the color glaze easy to adhere.

Otherwise, it is easy to appear rolling glaze, peeling glaze and other phenomena during color firing.

The firing temperature of white-glazed wares determines the color depth of green-glazed wares.

This kind of glazed porcelain is produced most by Cizhou kiln, and it is also the most distinctive.

For example, the Neon Osaka Municipal Museum of Oriental Ceramics has a green-glazed and black-picked peony-patterned long-necked bottle in its collection, which is a good example.

There are also kilns in the Nanhe area, but there are not many examples.

The Ding kiln was probably influenced by the Cizhou kiln, and it has been produced since the late Northern Song Dynasty. The best example is a green-glazed Ruyi head-shaped porcelain pillow unearthed from the early Jin Dynasty tomb in Nanxinzhuang, Shendu District.

Batches of white porcelain from the Ding Kiln were unearthed from this tomb. This pillow also belongs to the Ding Kiln in terms of its tire quality, but its shape and decoration are very similar to those of the Cizhou Kiln.