COD sensor, also called COD probe, is an instrument used to measure chemical oxygen demand in water or wastewater and supports online digital transmission. Utilizing the advanced UV254 ultraviolet absorption method, it ensures fast, accurate, and reliable organic content measurements, enabling continuous online monitoring of water quality. Beyond COD, this versatile sensor can also detect parameters such as Total Organic Carbon (TOC), Turbidity Units (TU), and Total Suspended Solids (TSS), making it suitable for applications requiring comprehensive water analysis. Its dual functionality as a COD-TSS sensor or COD-TU sensor enhances its utility in environmental protection, wastewater treatment, and industrial monitoring systems. Chemical Oxygen Demand (COD) is a key parameter for evaluating organic pollution in water. It measures the oxidant consumed during the oxidation of organic and certain inorganic materials in water. High COD levels signify excessive organic pollutants, which may deplete dissolved oxygen, adversely impacting aquatic ecosystems and water usability. Monitoring COD helps ensure compliance with environmental regulations and guides effective water treatment. COD Sensors use the UV254 ultraviolet absorption method to analyze water samples. Organic matter absorbs ultraviolet light when irradiated, and the intensity of absorption correlates with the organic content, allowing precise COD value calculations. This chemical-free method is efficient and ideal for a wide range of water samples, from drinking water to heavily polluted wastewater. COD Sensors and Probes are essential for precise and efficient water quality monitoring. With their ability to accurately measure Chemical Oxygen Demand, they play a vital role in environmental protection and industrial applications. By adopting these advanced tools, industries and researchers can better manage water resources and reduce pollution. Contact us for more information about our COD Sensors and other water quality solutions. COD Sensor,COD Probe,Chemical Oxygen Demand Sensor,Online COD Monitor,UV254 COD Measurement Suzhou Delfino Environmental Technology Co., Ltd. , https://www.daruifuno.comOverview
What is COD?
How COD Sensors Work
Key Features of COD Sensors
Applications
Conclusion
Three major problems in the existence of red sandalwood
Red sandalwood is among the most valuable woods globally, primarily found in the tropical regions of the South Sea Islands. Although China’s Guangdong and Guangxi provinces also produce rosewood, the quantity is limited. Indian lobular rosewood, often called "chicken blood rosewood," is currently considered the most precious type of rosewood, known for its superior quality. As the saying goes, the largest red sandalwood trees rarely exceed 20 centimeters in diameter, highlighting just how rare and valuable they are. Today, we’ll explore the three main issues associated with red sandalwood.
**First of the Three Main Issues: The Heartwood Development**
The seedlings of red sandalwood do not initially have purple heartwood. Only after a certain growth period does the heartwood gradually turn purple (fresh red sandalwood is usually orange-red). This color change results from the accumulation of the wood’s essence over time. High-quality red sandalwood has a smooth texture, resembling pure rosewood. When pressed, it feels almost like jade, with minimal wood fiber sensation. Carving and polishing such wood yields a texture similar to nephrite. The term "old red sandalwood" refers to pieces that are fine and free of brown eyes—these are likely filled with red sandalwood, making them less visible.
Due to the high concentration of red sandalwood, the annual rings in older pieces are often barely visible. The density of the wood increases as the red sandalwood accumulates, and once dried, some pieces may exceed a density of 1.3. In contrast, newly cut red sandalwood has a shorter growth period, meaning it hasn’t had enough time to develop this density. Therefore, only wild red sandalwood with a slow growth rate and long development cycle can be classified as "old." Even after decades of drying, the density and essence of new materials remain unchanged.
**Second of the Three Main Issues: Moisture Content and Cracking**
After being cut, wood naturally contains moisture, which slightly increases its physical density. However, as it dries over time, the water content decreases, making it more suitable for processing. During the drying process, many types of wood develop cracks due to internal stress changes caused by dehydration. This is a natural and unavoidable phenomenon.
Old red sandalwood that has been stored for years typically doesn’t crack further. Once the internal stress reaches equilibrium, the material becomes stable. Some polished red sandalwood exhibits flame-like marks on the surface, which are actually cracks that have oxidized over time, turning the affected area dark purple or black. Even if these cracks are sanded away, the oxidation traces remain beneath the surface.
**Third of the Three Main Issues: Hollowing**
It's commonly said that “ten sands and nine are hollow,†though the actual proportion may not be that extreme. The hollowness in red sandalwood is due to several factors. First, the central part of an old tree may have grown for over 500 years, leading to a natural hollowing process.
Additionally, while the tree is alive, it continuously produces red sandalwood, which is stored in the trunk. Over time, the conduits near the center become filled with mineral deposits, becoming increasingly compact. This leads to the breakdown of connections between the roots and leaves, much like a fruit that stops receiving nutrients and begins to rot. The hollowing process in red sandalwood is very slow, starting from the base and gradually spreading upward.
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