A novel preparation method was developed to form a surfactant-lipase complex for the resolution of 2-octanol in a solvent-free system. The E value was improved from 6.64 to 120.2. The lipase modified by the anion...A novel preparation method was developed to form a surfactant-lipase complex for the resolution of 2-octanol in a solvent-free system. The E value was improved from 6.64 to 120.2. The lipase modified by the anionic surfactant possessed a low solubility in the solvent-free system, which was beneficial to the recovery and the repeated usage of the lipase. The surfactant-lipase complex maintained a high enantioselectivity after five cycles of usage. The effect of water on both the activity and the enantioselectivity of the lipase has also been investigated; the direct addition of a salt hydrate pair of Na 4P 2O 7·H 2O and Na 4P 2O 7 can dramatically activate the modified enzyme.展开更多
Nicotinic acetylcholine receptors(nChRs) are involved in the various pharmacological effects or disease states.In order to study the central nChRs by PET or SPECT,some radioligands have been investigated.In this paper...Nicotinic acetylcholine receptors(nChRs) are involved in the various pharmacological effects or disease states.In order to study the central nChRs by PET or SPECT,some radioligands have been investigated.In this paper,the procedure for synthesis of 2-[^18F] fluoro-3-[2(S)-2-azetidinylmethoxy]pyridine(2-[^18F0-A-85380),a potential PET ligand for in vivo imaging nicotinic acetylcholine receptor was described.2-[^18F]-A-85380 was prepared from the precursor,2-nitro-3-[(1-(tert-butoxycarbonyl)-2-(S0-azetidinyl)methoxy] pyridine(4),which was synthesized with commercial (S)-2-zaetid-inecarboxylic acid as starting material.The whole procedure for radiosynthesis and purification was executed in about 1h and 45-55% of the added fluorine-18 was found in the purified 2-[^18F]-A-85380,with specific activity of 1.0-2.2×10^11 Bq/umol.展开更多
A transmission filter composed of a Sagnac loop and a fiber Bragg grating is studied in detail. It is found that the transmission spectrum of this filter is the splitting of the reflection spectrum of the fiber Bragg ...A transmission filter composed of a Sagnac loop and a fiber Bragg grating is studied in detail. It is found that the transmission spectrum of this filter is the splitting of the reflection spectrum of the fiber Bragg gratings. The filter can behave as a multiple-passband filter when the fiber Bragg grating is strong and as a single-band filter when the fiber Bragg grating is weak. Very narrow transmission filters can be Obtained in this way.展开更多
基金Supported by the National Natural Science Foundation of China( No.2 0 0 72 0 11and 2 0 2 72 0 17)
文摘A novel preparation method was developed to form a surfactant-lipase complex for the resolution of 2-octanol in a solvent-free system. The E value was improved from 6.64 to 120.2. The lipase modified by the anionic surfactant possessed a low solubility in the solvent-free system, which was beneficial to the recovery and the repeated usage of the lipase. The surfactant-lipase complex maintained a high enantioselectivity after five cycles of usage. The effect of water on both the activity and the enantioselectivity of the lipase has also been investigated; the direct addition of a salt hydrate pair of Na 4P 2O 7·H 2O and Na 4P 2O 7 can dramatically activate the modified enzyme.
文摘Nicotinic acetylcholine receptors(nChRs) are involved in the various pharmacological effects or disease states.In order to study the central nChRs by PET or SPECT,some radioligands have been investigated.In this paper,the procedure for synthesis of 2-[^18F] fluoro-3-[2(S)-2-azetidinylmethoxy]pyridine(2-[^18F0-A-85380),a potential PET ligand for in vivo imaging nicotinic acetylcholine receptor was described.2-[^18F]-A-85380 was prepared from the precursor,2-nitro-3-[(1-(tert-butoxycarbonyl)-2-(S0-azetidinyl)methoxy] pyridine(4),which was synthesized with commercial (S)-2-zaetid-inecarboxylic acid as starting material.The whole procedure for radiosynthesis and purification was executed in about 1h and 45-55% of the added fluorine-18 was found in the purified 2-[^18F]-A-85380,with specific activity of 1.0-2.2×10^11 Bq/umol.
文摘A transmission filter composed of a Sagnac loop and a fiber Bragg grating is studied in detail. It is found that the transmission spectrum of this filter is the splitting of the reflection spectrum of the fiber Bragg gratings. The filter can behave as a multiple-passband filter when the fiber Bragg grating is strong and as a single-band filter when the fiber Bragg grating is weak. Very narrow transmission filters can be Obtained in this way.
