博文

目前显示的是 二月, 2020的博文

Scintillation Crystal Material -- Magnesium Tungstate

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When the inorganic crystal is subjected to high-energy particles or high-energy rays (such as X-rays, gamma-rays), a phosphor that emits visible light due to excitation of particles or rays, which is a scintillation crystal, and magnesium tungstate is a scintillation crystal. Magnesium tungstate (MgWO 4 ) single crystal belongs to the wolframite structure, its melting point is 1358 °C. The crystal has a wide emission band of blue white light with a peak value between 480~500 and nm, in which the half width of the spectrum reaches 140nm, the luminescent intensity of magnesium tungstate is sensitive to impurities and excessive grinding, and the emission intensity of the scintillation crystal is weakened regardless of the substance. The excitation spectrum of MgWO4 is wider than PbWO 4 . In early studies of scintillators, MgWO 4  has the highest quantum efficiency, it is believed that the efficiency of converting 253.7 nm radiation to visible light is 100%. It is often used a

Acute Pancreatitis Detection Method of Phosphorus Magnesium Tungstate Precipitation Method

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Hyperlipidemia is one of the causes of hyperlipidemic acute pancreatitis, at the same time, hyperlipidemia is also the manifestation of metabolic disorder of acute pancreatitis. Patients with acute pancreatitis due to impaired pancreatic function, fat metabolism disorders, during the course of the disease, blood lipids rise dramatically, greatly increasing the amount of fat in the blood, the appearance of the patient's serum is extremely cloudy with milk, which is commonly referred to as severe chylous blood. Chylous blood interferes with colorimetric and turbidimetric tests of biochemical tests, leading to the fact that patients with acute pancreatitis are not diagnosed in time. And acute pancreatitis is an acute abdomen, the condition is critical, and even severe shock or death, the clinical need to grasp the relevant inspection data, in order to timely diagnosis. Some scholars believe that the phosphorus magnesium tungstate precipitation method can effectively

Scintillation Crystal Materials -- Cadmium Tungstate

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Cadmium tungstate (CdWO 4 ) single crystal is a scintillation detector with excellent scintillation properties. Its X ray absorption coefficient is large, the luminous efficiency is high, the afterglow time is short, and the radiation damage resistance is strong. It has extremely important application value in the field of nuclear medicine, X-ray, CT and container detection. Cadmium tungstate (CdWO 4 ) single crystal belongs to the tungstenite structure (monoclinic), its melting point is 1289 °C, with excellent performance, high luminous efficiency and energy resolution. In the process of growth, the crystal is easy to crack because of the cleavage plane. In 1948, the optical properties of cadmium tungstate crystals were reported for the first time. In 1950, some scholars made the crystals by flame. They were yellow green, but they were of poor quality. . With the development of the preparation technology, it is possible to prepare large size cadmium tungstate single c

Scintillation Crystal Material -- Barium Tungstate

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Barium tungstate is an important scintillation crystal material with excellent photoluminescence properties. Barium tungstate  has potential applications in the fields of nuclear spin hole, Raman scattering, solid-state laser and so on.  As the core component of the vacuum electronic device, the cathode must have the characteristics of large emitting current, low operating temperature, low evaporation rate and long service life, barium tungstate is a raw material that takes into account the high current, low evapotranspiration, long life cathode. Raman frequency shift technique is a nonlinear optical technique for obtaining a new wavelength laser by using the stimulated Raman scattering effect of Raman medium, barium tungstate crystal is a promising Raman crystal. In recent years, all solid state Raman lasers based on stimulated Raman scattering (SRS) effects of crystalline materials have become an attractive luminescent spot, the laser output from ultraviolet to near inf

New Material For Scintillation Crystal -- Lead Tungstate

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When the inorganic crystal is subjected to high-energy particles or high-energy rays (such as X-rays, gamma-rays), a phosphor that emits visible light due to excitation of particles or rays, which is a scintillation crystal, and lead tungstate is a scintillation crystal. This property makes lead tungstate an indispensable part in nuclear medicine, high-energy physics, nuclear technology, space physics and petroleum exploration. Scintillation crystal is mainly used for CT machine, particle collider, detector and even laser weapons and other manufacturing, the common oxide scintillation crystals are mainly bismuth germanate, cadmium tungstate, calcium tungstate, cadmium molybdate and calcium molybdate, lead tungstate is a new scintillation crystal found in 1990s relative to other crystals. Lead tungstate (PbWO 4 ) monocrystalline belongs to the scheelite structure, its melting point is 1123 °C, its scintillation performance is not lower than other tungstate crystals, In 1

Photocatalyst Combines - Phosphotungstic Acid mixed Titanium Dioxide

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At present, environmental pollution has become one of the most important concerns of mankind, especially organic pollutants. Their damage to the environment such as water, atmosphere and soil will be damaged if they are not dealt with in time, and cause an irreversible loss. In recent years, photocatalytic degradation has become one of the most important methods for organic pollutants because of its high efficiency, environmental protection and easy operation.  As far as photocatalytic reaction is concerned, titanium dioxide TiO 2  is one of the most studied semiconductors. This is due to its early application, cheapness, ease of handling, large specific surface area, and stability. Photocatalysis has attracted the most attention in the field of wastewater purification and treatment. But what can not be evaded is that TiO 2  band gap is wider (about 3.2 e V), it can only be excited by ultraviolet light, the use of solar energy is limited, photoinduced electron recombination wi

What Can Tungsten Do In The Age of Robots? (1)

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In July 26, 2017, in order to commemorate this gentleman, Baidu search engine replaced the home page Logo. Joseph Engelberg (Joseph, F, Engelberger), father of the robot, American, born in New York in July 26, 1925. In 1959, George DeVaul authorized patent technology to develop the world's first industrial robot, human beings entered the first year of robotics, and since then, the robot has brought great changes to the industry. Today, robots are no longer limited to industry, but are beginning to come into our lives. What will happen after ten years in the future, experts have predicted that after ten years of artificial intelligence (AI) will be the rapid development of integrated circuit, with higher speed, the progress of science and technology will be at top speed. On 2015, Premier Li Keqiang of the State Council put forward the strategy of "made in China 2025", and pointed out that China should enter the strategic target of "manufacturing pow

What Can Tungsten Do In The Age of Robots? (2)

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The robots of the future need to have high pressure, high heat resistance, wear resistance, corrosion resistance and other excellent physical conditions. They can be engaged in fire rescue, heavy load handling and underwater operation. Tungsten has the highest melting point, high temperature strength and creep resistance, as well as excellent thermal conductivity, electrical conductivity and electron emission. It will be an indispensable element in robot body casting, such as tungsten cobalt hard alloy, tungsten copper manufacturing body, can change the arbitrary shape, with a sticky, hydrophobic and high density of tungsten mud, for the robot needs flexible changes in the joint parts. The future robot needs superior intelligence and accurate judgment, capable of autonomous programming, intelligence, medical surgery, and intelligent care, tungsten thorium alloy and rare earth tungsten alloy can reduce the electronic work, so that the material has a high recrystallization tempe