The present invention relates to a silicon dioxide composite particle with far-infrared radioactivity, which is formed by the hydrolysis, condensation and polymerization of an organic silane precursor having the structure of the formula (I) with a tetra-alkoxysilane. The high stability of organic silane precursor compounds and the low biotoxicity of silicon dioxide composite particles make the present far-infrared radioactive silicon dioxide composite particles of great potential for extensive use in related bio-products.

A-R.sup.1Si(OR.sup.2).sub.3 Formula (I)

The present disclosure relates to a method for separating a carbon isotope and a method for concentrating a carbon isotope using the same, the method for separating a carbon isotope including: cooling a formaldehyde gas to a temperature of from 190K to 250K; and obtaining a mixed gas and residual formaldehyde by photodissociating the cooled formaldehyde gas, the mixed gas including carbon dioxide containing a carbon isotope and hydrogen.

Methods of selectively synthesizing n-tetrasilane are disclosed. N-tetrasilane is prepared by catalysis of silane (SiH.sub.4), disilane (Si.sub.2H.sub.6), trisilane (Si.sub.3H.sub.8), or mixtures thereof. More particularly, the disclosed synthesis methods tune and optimize the n-tetrasilane:i-tetrasilane isomer ratio. The isomer ratio may be optimized by selection of process parameters, such as temperature and the relative amount of starting compounds, as well as selection of proper catalyst. The disclosed synthesis methods allow facile preparation of n-tetrasilane.

The object of the present invention is to provide a stable isotope enrichment device and a stable isotope enrichment method capable of reducing the discharge amount of toxic or combustible substances or substances causing environmental load in the atmosphere and reducing the amount of raw materials used. The present invention provides a stable isotope enrichment device, including: a distillation column group in which a plurality of distillation columns are connected in a cascade; a raw material supply line (30) that supplies a raw material into a first distillation column (1); a product line (31) that withdraws a product from another distillation column located on the secondary side of the first distillation column (1); an isotope-depleted fluid withdraw line (32) that withdraws an isotope-depleted gas or an isotope-depleted liquid from the first distillation column (1) or another distillation column located on the primary side of the one distillation column (1); an isotope exchange reactor (22) at which the isotope-depleted gas or the isotope-depleted liquid is subjected to an isotope exchange reaction, the isotope-depleted gas or the isotope-depleted liquid is regenerated such that the concentration of molecules containing a target stable isotope in the isotope-depleted gas or the isotope-depleted liquid approaches the natural abundance ratio, and an isotope-regenerated gas or an isotope-regenerated liquid is produced; and an isotope-regenerated fluid return line (33) that re-supplies the isotope-regenerated gas or the isotope-regenerated liquid into the first distillation column (1).

A method of separating Osmium from Iridium, including receiving a powdered mixture of Osmium and Iridium, oxidizing the Osmium of the powdered mixture, capturing the oxidized Osmium in a trapping solution, reducing the oxidized Osmium from the solution to release the Osmium.

A sensor system is based on diamonds with a high density of NV centers. The description includes a) methods for producing the necessary diamonds of high NV center density, b) characteristics of such diamonds, c) sensing elements for utilizing the fluorescence radiation of such diamonds, d) sensing elements for utilizing the photocurrent of such diamonds, e) systems for evaluating these quantities, f) reduced noise systems for evaluating these systems, g) enclosures for using such systems in automatic placement equipment, g) methods for testing these systems, and h) a musical instrument as an example of an ultimate application of all these devices and methods.

Calibration devices including germanium-68 source material are disclosed. The source material may be a matrix material (e.g., zeolite) in which germanium-68 is isomorphously substituted for central atoms in tetrahedra within the matrix material. Methods for preparing such calibration devices are also disclosed.

Water is separated into deuterium-depleted water having a low deuterium concentration and deuterium-enriched water having a high deuterium concentration easily and at low cost.

A method for separating water into deuterium-depleted water and deuterium-enriched water, the method including: adsorbing water vapor on an adsorbent including a pore body having pores 6 while supplying water vapor to and allowing the water vapor to pass through the adsorbent for a predetermined period of time; recovering deuterium-enriched water containing a large amount of heavy water 8 from the water vapor not adsorbed on the adsorbent; and then recovering deuterium-depleted water containing a large amount of light water 7 from the water vapor adsorbed on the adsorbent.

The present disclosure relates to the technical field of separation of boron isotopes, in particular to a device and method for cracking a boron trifluoride complex. The device for cracking the boron trifluoride complex includes a continuous feeding system, a rising film preheater, a falling film preheater, a boron trifluoride gas circulation pipeline, a separation chamber, a cracking tower, a gas-liquid separator, an impurity removal tower, and anisole storage tank. By employing a continuous feeding method, the device for cracking boron trifluoride complex shortens retention time of anisole at a high-temperature stage while ensuring a cracking rate of a boron trifluoride-anisole complex, reduces the thermal decomposition degree of anisole, maintains the purity of anisole, and greatly improves the utilization rate and production safety of anisole, thus ensuring continuous and stable production.

Provided are a system for preparing isotope-labeled carbon dioxide and a method therefor. The preparation method comprises: vaporizing heavy-oxygen water and mixing the heavy-oxygen water with carbon dioxide, and subjecting the heavy-oxygen water and the carbon dioxide to an oxygen-exchange reaction by catalyzing them with a catalytic material, and performing gas-liquid separation after the reaction to obtain the isotope-labeled carbon dioxide. The system provided by the present application has a simple structure, and by adopting the heavy-oxygen water which has a wide source and low cost as an oxygen isotope source and utilizing the oxygen-exchange reaction, the replacement of oxygen-16 in normal carbon dioxide by oxygen-18 in heavy-oxygen water is achieved to obtain the oxygen-18 labeled carbon dioxide product. The process is simple and pollution-free, the utilization rate of oxygen isotope is high, the conditions of separation and purification are mild, and the system has good economic benefits and application prospects.