11 results about "Periodic acid" patented technology

The present disclosure relates to the synthesis of Vitamin K2 bearing varying prenyl side chains. The synthesis comprises the reaction of phenyl sulfone of tert-butyl dimethyl silyl (TBDMS) protected mono prenyl menadiol with prenyl halides bearing varying prenyl units in the presence of the phase transfer catalyst followed by reductive desulphonation to yield TBDMS ether of Vitamin K2. The TBDMS ether is then oxidized in the presence of chromium trioxide and periodic acid to yield the corresponding Vitamin K2.

The present application relates to a kind of 1D / 2D double heterojunction catalyst and its preparation method and its application in photo-assisted high iodate activation degradation bisphenol A.The preparation method of the present application: concentrated hydrochloric acid solution and LiF are mixed, Ti3AlC2 is added, heated reaction, solid-liquid separation is taken solid phase, after washing to neutral, dispersed in ethanol, to obtain MXene ethanol solution;Cerium source aqueous solution is added to MXene ethanol solution and mixed in liquid nitrogen, to obtain mixed solution;Organic ligand, ethanol and pure water are mixed to obtain mixed solution, the mixed solution and mixed solution are mixed and heated, solid-liquid separation is taken precipitate, freeze-drying is obtained powder;The obtained powder is heated and calcined under inert atmosphere, to obtain 1D / 2D double heterojunction catalyst.The present application effectively inhibits photo-generated electron hole recombination by constructing double heterojunction, while realizing ultrafast electron transfer, to enhance oxidation, realizes the high-efficiency photocatalytic activity of "1+1>2".

The invention provides compositions useful in the etching of polysilicon in the presence of silicon oxide and silicon nitride. The compositions comprise choline hydroxide, an oxidizing agent such as periodic acid, and optionally a surfactant, and are useful in the etching of polysilicon in general, and in particular in both the operation of polysilicon trim as well as polysilicon exhume. The utilization of an added oxidizing agent was found to reduce selectivity of silicon etching based on the silicon crystal orientation, which was found to reduce roughness and the presence of residual silicon residues, such as silicon (111) residues after the etching step.

The invention belongs to the technical field of iodine removal of light salt brine, and particularly relates to a method for removing high-valence iodine in ionic membrane caustic soda light salt brine. Comprising the following steps: (1) adding a pH regulator and sodium sulfite into light salt brine, regulating the pH to 1-3, stirring until the reaction is completed, and carrying out primary adsorption deiodination by adopting a composite adsorbent to obtain light salt brine 1; and (2) adding a pH regulator and hydrogen peroxide into the light salt brine 1, regulating the pH value to 1-2, stirring until the reaction is completed, and carrying out secondary adsorption by adopting a composite adsorbent to remove iodine, thereby obtaining the deiodinated light salt brine. According to the removal method disclosed by the invention, high-valence iodine such as periodate and iodate in the light salt brine is converted into low-valence iodine such as iodate and iodide ions by utilizing the reducibility of sodium sulfite and the oxidation-reduction property of hydrogen peroxide in the coexistence of iodide ions and iodate, and then is further converted into simple substance iodine, and the simple substance iodine is efficiently removed by utilizing a composite adsorbent; the process is simple, the cost is low, the removal rate is high, and the removal effect is good.

The invention relates to the fields of chemistry and chemical engineering, organic synthesis and medicinal chemistry, in particular to a method for synthesizing 5-bromo-2-chlorobenzoic acid by adopting a microchannel reaction device. The method comprises the following steps: I, mixing 2-chlorobenzoic acid and sulfuric acid to obtain a reaction solution A; mixing bromine, sodium periodate, liquid organic acid and water to obtain a reaction solution B; and II, feeding the reaction liquid A and the reaction liquid B into a micro mixer of a micro-channel reaction device for mixing, then feeding the mixture into a micro reactor of the micro-channel reaction device for contact reaction, and carrying out post-treatment on contact reaction effluent to obtain the 5-bromo-2-chlorobenzoic acid. The method has the advantages of high product selectivity, high yield, high purity, convenient process, low production cost, and less by-product and three-waste pollution.

The invention discloses a high-polysaccharide dendrobium officinale variety germination period directional screening cultivation method, and belongs to the technical field of tissue culture. The invention provides a high-polysaccharide dendrobium officinale variety germination period directional screening cultivation method aiming at the problems that existing dendrobium officinale germplasm is mixed and the polysaccharide content is unstable. According to the method, the concentration of a periodate solution adopted for acidolysis treatment is remarkably reduced, the acidolysis time is shortened, a chromogenic reaction is achieved outside the protocorm, the situation that epidermal cells of the protocorm are excessively damaged and a coloring agent enters the protocorm to cause tissue structure change is avoided, and it is guaranteed that the structure of dendrobium officinale is complete and the shape of dendrobium officinale is stable; meanwhile, the dyeing time is shortened, rapid and lossless identification of the dendrobium officinale high-polysaccharide germplasm in the protocorm stage is achieved, the breeding period is remarkably shortened, and the screening accuracy and efficiency are improved. The cultivated high-polysaccharide dendrobium officinale variety shows consistency and stability in the aspects of polysaccharide content and agronomic traits.

This scheme discloses a method for adsorbing cadmium ions in the field of heavy metal adsorption technology, specifically: using acylhydrazone-sodium alginate-Ca 2+ Composite adsorbent for heavy metal Cd 2+ Adsorption occurs, wherein the acylhydrazone-sodium alginate-Ca 2+ The composite adsorbent is prepared by reacting salicylhydrazine with sodium hydroxide after alkalization and oxidation with sodium periodate to form a salicylhydrazone compound, which is then cross-linked with sodium alginate. The method described in this application can simultaneously reduce the amount of distiller's grains and the heavy metal Cd. 2+ Pollution.

The application discloses a method for removing odorants in water by using an ozone / potassium periodate homogeneous phase, which comprises adding ozone (O3) and potassium periodate (IO4 ‑ ) into water containing odorants; adjusting the pH value of the water to 6.0-8.0; and reacting for 3-10 minutes at 0-35 DEG C; wherein the molar ratio of O3 to IO4 ‑ is 1:2-10:1, the ozone dosage is 2.0-8.0 mg / L, and the potassium periodate dosage is 3.0-15.0 mg / L. The method can generate high-activity free radicals (·OH, IO3·, etc.) by using a homogeneous phase catalytic system, and thus realizes efficient degradation of the odorants.

This invention proposes a method for determining the glycerol content in collagen colloids. It utilizes the oxidation of free glycerol by periodic acid to formaldehyde, which then undergoes a Hantzsch reaction with two molecules of acetylacetone in the presence of ammonium acetate. This is the first time this method has been applied to the determination of glycerol content in collagen colloids, and it is automated using an automated analyzer. This method can be used to detect collagen colloidal materials. The sample pretreatment primarily utilizes the isoelectric point precipitation property of collagen. The pH of the collagen solution sample is pre-adjusted to approximately 5.0, close to the isoelectric point of collagen colloids. The precipitation of proteins clarifies the solution and facilitates the release of glycerol into the solution, resulting in more accurate measurement results. This invention offers advantages such as simplicity, speed, accuracy, and safety in determining the glycerol content in collagen colloids.

The invention discloses a finasteride intermediate as well as a preparation method and application thereof, and belongs to the technical field of medicine synthesis. The preparation method of the finasteride intermediate comprises the following steps: mixing progesterone and an organic solvent, continuously introducing ozone at-20 DEG C to-10 DEG C to obtain an intermediate state I, dropwise adding peroxide at-10 DEG C or below, dropwise adding a sodium hydroxide solution, heating to 15-25 DEG C, and reacting to obtain the finasteride intermediate. In addition, the invention also provides the finasteride intermediate which is prepared by the preparation method. In addition, the invention also provides an application of the finasteride intermediate in preparation of finasteride. According to the method, sodium periodate does not need to be used, 4-position double bonds can be cut off through oxidation by adding a small amount of peroxide and a sodium hydroxide solution, the finasteride intermediate is obtained, and the green chemical requirement is met.

The invention provides a method for rapidly determining the content of triethylene glycol in refined polyethylene glycol based on redox titration, which comprises the following steps: weighing two polyethylene glycol samples with the same mass, selectively oxidizing ethylene glycol in one of the polyethylene glycol samples by utilizing periodic acid, and determining the content of ethylene glycol in combination with redox titration; the total hydroxyl value of the other part is measured, and the content of triethylene glycol is calculated through difference derivation according to the hydroxyl value characteristics of ethylene glycol, triethylene glycol and polyethylene glycol. The method does not need a large instrument, is simple and convenient to operate, consumes short time and is suitable for rapidly detecting the content of triethylene glycol in refined polyethylene glycol.