The drainage principle of gravel filter
The inverted filter layer was made of 2 - 4 layers of sand, gravel, pebbles, and other materials with different particle sizes. The particle size was graded from fine to coarse along the direction of the water flow. The principle of drainage was that when the permeating water passed through the inverted filter layer, because the particle size of each layer gradually increased along the direction of the water flow, the particles of any layer were not allowed to pass through the pores of the adjacent thicker layer, and the particles of the same layer could not move relatively. In this way, the water flow could pass smoothly, and at the same time, it could prevent the soil in the dam body or foundation from being brought out by the permeating water, thus realizing the drainage function and preventing the occurrence of piping and flowing soil. Read more exciting novels for free
Reflection principle of filter
The reflective filter is composed of loss-free reactor components (such as inductors, condensers, or their combined network). The principle was based on reflecting interference waves of unwanted frequencies back to the signal source to achieve frequency selection and filtering purposes. In the design, the filter should have a low series resistance and a high parallel resistance in the band-pass range, and the parallel resistance in the stop-band range should be very small and the series resistance should be very high. When the electromagnetic interference spectrum emitted by the interference source is wider than the received signal spectrum, the receiver will receive the interference signal when it receives the useful signal. The reflection filter can reflect the stopband frequency back to the signal source, limit the frequency band of the received signal, suppress the useless interference without affecting the useful signal, thereby improving the signal-to-noise ratio of the receiver and significantly reducing the level of conducted interference. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Open ditch drainage and underground ditch drainage
Open ditch drainage and underground ditch drainage were two different drainage methods. Open ditch drainage referred to the drainage of water through the excavated open ditch channel. Water could flow directly from various positions in the ditch. The cover was usually a comb, which could pass water. The comb or grill was used to intercept debris. Underground ditch drainage meant that water could not flow in directly. The cover was usually steel plate or concrete. The drainage ditch of the underground ditch was inclined to the water collecting well. When digging, the drainage ditch was first dug, and as it was dug, it deepened to form a underground ditch system connecting the inside and outside of the foundation pit to control the underground water level. Finally, the underground water was pumped away by a pump. Open ditch drainage was suitable for irrigation in areas with water infiltration, and it had a good effect on rainwater drainage. Dark ditch drainage was suitable for the foundation pit drainage of structures with large foundation pit depth, narrow site, and strong underground water.
Open ditch drainage and underground pipe drainage
Open ditch drainage and underground pipe drainage were two common methods of farmland drainage. Open ditch drainage was a method of digging drainage ditches to form a drainage ditch network. Water would flow from the field ditch network into the water transmission ditch network and finally into the drainage area (river, lake, sea). Underground drainage was a method of burying pipes underground to drain water by removing excess water from the farmland soil and lowering the water level. The underground pipe drainage could be used to filter and seep water by using sand and stone bedding, laying thick plastic pipes and crushed sand. Open ditch drainage was suitable for soil layers with better geological conditions, while underground pipe drainage could effectively control the underground water level, save land, and have a better drainage effect.
Open ditch drainage, underground ditch drainage
Open ditch drainage and underground ditch drainage were two different drainage methods. Open ditch drainage referred to the digging of open ditches on the surface to guide water to the water outlet. It was suitable for draining accumulated water after heavy rain or for green areas with uneven terrain. Open ditches had the advantage of easy drainage, easy flushing, and anti-blockage, but there might be problems with odors and pests, and it would also make the ground uneven. Underground ditch drainage was used to draw water out by burying pipes or building underground ditches. It was suitable for narrow sites and large underground water. Underground ditches could keep the terrain neat and save land, but the cost was higher. There were differences in drainage methods, cover materials, and functions between open ditches and underground ditches.
promotion and drainage
The following are some common methods to promote drainage: 1. ** Social media promotion **: It has a wide coverage and low cost, but the content must be attractive and know how to interact with users. 2. ** Online advertisement promotion **: Able to accurately target users, but the advertising cost is high. You must choose the platform and strategy carefully. 3. ** content marketing **: It helps to build user trust and improve brand image. It requires high-quality content and continuous updates. 4. ** Promotional articles **: It can influence users subtly. You need to find a suitable platform and channel. 5. ** Q & A Promotion **: Answer user questions through the Q & A platform and provide valuable answers to increase brand exposure and user attention. High-quality content can show long-term promotion effects. 6. ** We-media Channel Promotion **: Use the We-media platform to spread original and high-quality content to attract users 'attention and improve the brand image. 7. ** Video Promotion **: Create high-quality and highly relevant video content and upload it to the video platform. Use the Short videos traffic and exposure to promote it. 8. ** WeChat marketing **: Use WeChat's various functions to push promotions and event news to increase user participation. 9. ** domestic APP advertising promotion **: Placing promotional content in the advertising space of popular APP platforms to accurately reach the target users. 10. ** Information flow advertisement promotion **: Placing information flow advertisements on online media, social media, and other platforms to accurately reach users and increase brand awareness. 11. ** Community Promotion **: Create a community around your own industry and organize regular activities to attract target users to participate in interactions. 12. ** Resource Cooperation Promotion **: Cooperate with other websites in terms of resources, such as links, advertisements, content, etc., to achieve mutual promotion. 13. ** Fission Marketing Promotion **: Through the reward mechanism and user recommendations, users can promote themselves, increasing user conversion and brand communication. 14. ** Weibo Promotion **: It is highly open. You need to continuously output content and use functions such as reposting and lottery to attract fans. 15. ** Peers recommend each other **: Find similar industries to promote to each other to obtain more accurate customer resources. 16. ** Bait Techniques **: For example, mention valuable content in the community to attract others to add, or upload attractive resources on well-known websites to attract interested people. 17. ** Mass posting **: For example, using the number advantage of the WeChat group to increase the exposure of the content. 18. ** Enterprise WeChat Promotion **: Use various marketing tools of Enterprise WeChat for marketing. You can import mobile phone numbers to add users. 19. ** Matrix keyword promotion **: For example, restaurants can publish information with specific keywords (such as local food) on platforms such as Little Red Book. 20. ** Create a unique charm and build an IP (as in TikTok)**: Build a unique personal or brand IP to attract fans. 21. ** Livestream interaction (as if on TikTok)**: Build private domain traffic through livestream. 22. ** Online and offline integration (as in TikTok)**: Combining offline activities for online promotion. 23. ** For the mall's Mini programs **: It has a beautiful interface design and rich product content. Through cooperative promotion (with relevant platforms, social media, and blog, etc.), it uses special promotions, lucky draws, and offline promotion and event traction.
Spiral drainage pipe
Spiral drainage pipe was a kind of pipe used in building drainage system, which had some characteristics and advantages. Spiral drainage pipe has the following characteristics: 1. Reduce noise: The design of the spiral drainage pipe can effectively reduce the noise pollution caused by drainage. The measured results showed that compared with the traditional cast iron drainage pipe, the noise of the spiral drainage pipe was about 2 to 4 decibels lower, and it had a silencing effect. 2. To prevent the damage of the floor drain seal: The spiral structure inside the spiral drainage pipe can reduce the pressure fluctuation in the pipe, avoid the damage of the water seal caused by the negative pressure of the upper user and the positive pressure of the bottom user, and improve the stability of the drainage system. 3. Increase drainage efficiency: The internal spiral structure of the spiral drainage pipe increases the friction resistance of the water flow, preventing the water flow from blocking the pipe due to inertia, improving drainage efficiency and reducing the occurrence of blockage accidents. 4. [Double silencing effect: Hollow wall spiral drainage pipe is a special structure of spiral drainage pipe. It has a double-layer structure and honeycomb-shaped holes, which can further isolate noise and have a better silencing effect.] In general, the spiral drainage pipe had the advantages of reducing noise, preventing the damage of the floor drain seal, and improving drainage efficiency. They are commonly used in the drainage system of buildings, especially for the drainage of single standpipes in high-rise buildings.
same floor drainage
Same-floor drainage was a drainage method for sanitary appliances. Its characteristic was that the drainage pipe did not need to pass through the floor, but was laid in the same floor and connected to the drainage standpipe. There were two main forms of same-floor drainage: wall-row zero-drop same-floor drainage and slightly-drop same-floor drainage. The wall row zero-drop drainage on the same floor meant that the drainage pipe went along the wall and did not occupy the vertical floor height. The bathroom could maintain the same floor height as other rooms, and the design freedom was higher, and it was beautiful and practical. The same floor drainage with micro-descending plates was a common form in China. It required the installation of dry area floor drain, which could almost achieve zero floor height difference without occupying vertical floor height. The difference between the same floor drainage and the different floor drainage was the layout of the bathroom appliances, the aesthetics of the house, and the drainage noise. The advantages of same-floor drainage were high degree of freedom in layout, beautiful houses, and low drainage noise, but there were also shortcomings such as high construction cost and difficult maintenance. In general, same-floor drainage was a healthier, more convenient, and more beautiful drainage method.
open ditch drainage
Open ditch drainage was a commonly used method of drainage. It was suitable for the removal of a small amount of underground water, surface water, and rainwater in the foundation pit. Open ditch drainage is composed of open drainage ditch, water collecting well, water intake, horizontal support, vertical support plate, etc. The conditions for the use of open ditch drainage include geological conditions and aquatic conditions. The geological conditions were suitable for denser soil layers, especially soil layers with a certain degree of cohesion or stickiness, as well as hard clay mixed with sand lenses or thin layers without water supply. The water condition is suitable for the situation where the flow of underground water is small. The construction plan of open ditch drainage included the arrangement of the drainage line, the number and location of the water collecting wells, the excavation of the open ditch and the setting of the water collecting wells. The open ditch drainage method had the advantages of low cost, simple construction, and obvious effect. It was widely used in fields such as farmland, urban roads, and gardens.
Character Introduction of The Gravel of the Past
The characters included the male protagonist, Yan Chengan, and the female protagonist, Zhao Muzhi. They were born to be a straight-A student, but they felt uncomfortable if they didn't study for a day. They were full of golden fingers, but they just didn't get popular. Author of "The Gravel of the Past": That Seventeen is a modern romance/entertainment star novel. It's finished and you can enjoy it without worry. User recommendation: Why is the road ahead of the straight-A student who was originally smooth-sailing not smooth after picking up the protagonist halo? If he couldn't be a Goldfinger, how could he become the male lead? The villain's soul asked, Who am I? Where am I? Can this story give me a chance to do something big? Without me, what are you guys doing? Welcome to Close to Science: Farming in the Entertainment Park... I hope you will like this book.
Are the stars called silver gravel?
Stars could be called silver gravel, which was another name for stars. The novel " The Name Engraved in the Stars of Destiny " is equally exciting. Everyone is welcome to click and read it!