Abstract: A method for preparing (S)-nicotine by reduction includes conducting a reduction process on an alkene compound as shown in Formula I and/or an iminium cation compound as shown in Formula II, thereby producing (S)-nicotine. The method is simple, safe, reliable, and yields both high purity and high quantities of (S)-nicotine production.

Abstract: Provided is a method of preparation of (1R, 3S)-3-amino-1-cyclopentanol, the method including: contacting N-acylhydroxyamine and cyclopentadiene for an asymmetric cycloaddition, to yield a first intermediate I; hydrogenating the first intermediate I to yield a second intermediate II; hydrolyzing, ammonolyzing, hydrazinolyzing, or alcoholyzing an amido bond of the second intermediate II to yield a third intermediate III; and hydrogenating the third intermediate III to yield (1R, 3S)-3-amino-1-cyclopentanol.

Abstract: A fat extract without added ingredients can be used in the preparation of a composition or product for one or more uses amongst (a) promoting proliferation of fibroblasts; (b) promoting anti-aging of fibroblasts; and (c) promoting production of type I collagen in fibroblasts. The preparation method for the fat extract without added ingredients, a pharmaceutical or cosmetic composition containing the fat extract without added ingredients, and a method for culturing fibroblasts in vitro are also provided. The fat extract without added ingredients can effectively and cooperatively inhibit skin aging, prevent fibroblast apoptosis, promote fibroblast proliferation and collagen synthesis, and promote skin rejuvenation.

Abstract: Provided is a method of preparation of (1R, 3S)-3-amino-1-cyclopentanol, the method including: contacting N-acylhydroxyamine and cyclopentadiene for an asymmetric cycloaddition, to yield a first intermediate I; hydrogenating the first intermediate I to yield a second intermediate II; hydrolyzing, ammonolyzing, hydrazinolyzing, or alcoholyzing an amido bond of the second intermediate II to yield a third intermediate III; and hydrogenating the third intermediate III to yield (1R, 3S)-3-amino-1-cyclopentanol.

Abstract: This invention provides a double-sided glass, and relates to a technical field of glass. The double-sided glass includes a glass body, a first color layer, and a second color layer. The first color layer and the second color layer are both disposed at a same side of the glass body. By arranging the first color layer and the second color layer on the same side of the glass body, the glass body does not need to be flipped during manufacturing, which greatly reduces the production difficulty and improves the production effectiveness. Secondly, since the first color layer and the second color layer are disposed on a same side, it is not necessary to seal surrounding edges of the glass body.

Abstract: A parking lot entrance recognition method comprises the steps: reading GPS data of all vehicles appearing in a specified region within a specified time one-by-one; acquiring discontinuity points after it is confirmed that vehicle position information is lost; and comparing the discontinuity frequency of each discontinuity point with a frequency threshold to determine whether or not the discontinuity point is an entrance of an underground parking lot. In this way, the entrances of parking lots can be rapidly positioned, so that drivers can park conveniently and can also drive purposefully; and meanwhile, based on the analysis of the GPS data, the positioning accuracy is higher.

Abstract: A parking lot entrance recognition method comprises the steps: reading GPS data of all vehicles appearing in a specified region within a specified time one-by-one; acquiring discontinuity points after it is confirmed that vehicle position information is lost; and comparing the discontinuity frequency of each discontinuity point with a frequency threshold to determine whether or not the discontinuity point is an entrance of an underground parking lot. In this way, the entrances of parking lots can be rapidly positioned, so that drivers can park conveniently and can also drive purposefully; and meanwhile, based on the analysis of the GPS data, the positioning accuracy is higher.

Abstract: A method for preparing a rosuvastatin calcium intermediate, including a) contacting a halogenated ethene with magnesium metal to obtain a halogenated ethene Grignard reagent, and carrying out a Grignard reaction between the halogenated ethene Grignard reagent and R-epichlorohydrin; b) adding sodium cyanide for carrying out a nucleophilic substitution reaction; c) adding alcohol for carrying out an alcoholysis reaction; d) adding a basic solvent for carrying out protection of a first hydroxyl group; e) selectively oxidizing a second hydroxyl group; and f) adding triphenylphosphine in alkaline condition for carrying out a Wittig reaction.

Abstract: A method for preparing a rosuvastatin calcium intermediate represented by formula I. The method includes: hydrolyzing an ester compound represented by formula II (in which, R represents C1-C5) in the presence of a metal compound to obtain a carboxylic acid compound represented by formula III; and reducing the carboxylic acid compound in the presence of a reductant.

Abstract: A method for preparing a rosuvastatin calcium intermediate, including a) contacting a halogenated ethene with magnesium metal to obtain a halogenated ethene Grignard reagent, and carrying out a Grignard reaction between the halogenated ethene Grignard reagent and R-epichlorohydrin; b) adding sodium cyanide for carrying out a nucleophilic substitution reaction; c) adding alcohol for carrying out an alcoholysis reaction; d) adding a basic solvent for carrying out protection of a first hydroxyl group; e) selectively oxidizing a second hydroxyl group; and f) adding triphenylphosphine in alkaline condition for carrying out a Wittig reaction.