37 results about "Cis trans isomerization" patented technology

An image forming apparatus has a photosensitive member configured to transport a developer containing a compound that causes cis-trans isomerization reaction by light absorption to induce phase transition; a first exposure device configured to emit ultraviolet light having a wavelength of 300 nm-400 nm to a developer image; and a pressing member configured to press a recording sheet holding a developer image exposed by the first exposure device thereon. It is possible to achieve conservation of energy during image formation.

A detection method of cis-trans isomers in cis-propenyl phosphonic acid and related impurities thereof is applicable to the field of pharmaceutical analysis, and the method comprises the following steps and conditions: the chromatographic conditions are that the chromatographic column is a C-18 column of 4.6 mm*250 mm*5.0 microns; the flow velocity is 1.0 ml / min; an ultraviolet detector has a detection wavelength of 225 nm and a sample size of 10 microliters; the mobile phase is 50 mmol / L dipotassium hydrogen phosphate aqueous solution-methanol; preparing a test solution by dissolving 0.1 microliters of test samples in the mobile phase, diluting to 25 ml, and filtering; introducing 10 microliters of the test solution, recording a spectrum, wherein the retention time for cis-propenyl phosphonic acid is 12.3 min, the relative retention value of its cis-trans isomers is 1.15, and the relative retention value of propadiene phosphonic acid is 0.38, and calculating the contents of various impurities by an area normalization method; in the mobile phase, the 50 mmol / L dipotassium hydrogen phosphate aqueous solution contains 2% of tetrabutylammonium hydroxide aqueous solutions; the concentration of the tetrabutylammonium hydroxide aqueous solution is 55%. According to the invention, the method is used for the detection of cis-trans isomers in cis-propenyl phosphonic acid and related impurities thereof, and the repeatability, the sensitivity, and the accuracy all meet the requirements.

The invention discloses a solid phase microextraction method of unsaturated fatty acid. A silver nanoparticle immobilized monolithic column is used as a solid phase microextraction monolithic column, and the solid phase microextraction method of unsaturated fatty acid is established in combination with an in-tube solid phase microextraction-high performance liquid chromatography system. The unsaturated fatty acid is enriched under the interaction of silver nanoparticles on the surface of the monolithic column and carbon-carbon double bonds of the unsaturated fatty acid; different isomers of the unsaturated fatty acid are sequentially eluted under different acting forces between the silver nanoparticles and the isomers of the unsaturated fatty acid. The method is simple, the process is ingenious, required instruments have higher popularization degree, the method is easy to popularize, efficient enrichment of the unsaturated fatty acid and sequential elution of different cis-trans-isomers can be realized, and the efficient detection requirement of trans-fatty acid can be met.

The invention provides a method for producing all trans-teprenone, comprising the following steps of: (1) synthesizing teprenone through Carroll reaction to obtain a teprenone crude product; (2) pickling the teprenone crude product by the use of hexane and sulfuric acid, carrying out alkali washing by the use of a sodium bicarbonate solution, washing to neutral, and removing an emulsification layer and a water layer to obtain mixed teprenone after washing; (3) adding hexane for dilution, standing at minus 15-minus 20 DEG C for 20-24 hours, cooling to minus 30-minus 60 DEG C, and crystallizing all trans-teprenone; and (4) centrifuging the crystals at minus 20-minus 40 DEG C to obtain the all trans-teprenone having a purity of greater than 99%. Through an ultralow temperature separation method and an apparatus, all trans-teprenone having a purity of greater than 99% is obtained from a cis-trans isomer which is hard to separate under the condition of high temperature and other purities which can be separated by a rectification means. In addition, cis and other impurities do not exceed 1%.

The invention discloses a preparation method and an application of an isomerization catalyst and aims to solve the problem of low yield of a target product due to presence of an isomer in a productionprocess of the compounds. A precursor of the catalyst is prepared from composite oxide or the composite oxide which is impregnated with a certain amount of metal salt, the precursor of the catalyst is roasted at 350-450 DEG C, subjected to sheet forming and compression forming, and subjected to HF fluoridation at 200-400 DEG C, and the fluorination catalyst is prepared. The catalyst is mainly applied to a cis-trans isomerization reaction process of hydrofluoro olefin or hydrochlorofluoro olefin.

The invention provides a preparation method of a photoresponse film, which comprises the following steps of: dissolving chitosan powder in an acetic acid aqueous solution, adding 4,4'-dihydroxyazobenzene dissolved in a strong polar solvent, fully stirring, removing visible bubbles in the solution, standing in a 5 DEG C environment under protection of nitrogen, uniformly pouring a clear solution into a mold, placing the mold in a constant-temperature oven to remove the solvent, taking out after 40 hours, forming the film, and washing the film with a sodium hydroxide aqueous solution to remove the film to obtain a photoresponse unbraced film. Compared with the prior art, the preparation method of the photoresponse film saves complex operation and cost in a preparation process of a polymer; and meanwhile, an azobenzene derivative is combined with chitosan molecules by hydrogen bonds, so that the molecular size change in a cis-trans isomerization process of the azobenzene is amplified, ultraviolet light irradiation is bent to a comparatively large extent, the bending is restored under the irradiation of visible light, and model design of photoinduced artificial muscle is achieved.

The invention belongs to the technical field of polymer materials and specifically relates to a photo-repair azobenzene polymer and a preparation method thereof. The preparation method comprises the steps: firstly, carrying out multi-step reactions such as etherification, nitro-reduction, diazo coupling and esterification on p-nitrophenol to obtain monomers containing anthracene and azobenzene groups, namely 4'-(hexyl methacrylate-oxyl)-4-(anthracene-2-methylacetate)azobenzene(MMA-AZO-AN); and then, carrying out free radical polymerization on MMA-AZO-AN serving as a monomer under the conditionthat an initiator exists to prepare the 4'-(hexyl methacrylate-oxyl)-4-(anthracene-2-methylacetate)azobenzene(MMA-AZO-AN). The novel photo-repair azobenzene polymer is prepared by applying the cooperation of two photo-responsive structures in combination with a reversible Diels-Alder addition reaction generated by the anthracene group under the condition of light excitation and a reversible cis-trans isomerism behavior generated by azobenzene under the conditions of ultraviolet light and visible light excitation.

The invention relates to a preparation method of antisotropic azo polymer / carbon tube composite thin film with photo-responsitivity. An azo polymer and a modified carbon tube composite film are prepared into a flexible polymer thin film with in plane anisotropy through synthesis of the azo polymer and modification of a carbon tube film; a flexible thin film with in-plane conducting anisotropy can be obtained through polymer molecular chains are orientated along a carbon tube under the induction of the carbon tube, and the conductivity in the in-plane horizontal direction is higher than that in the direction which is vertical to the carbon tube by one order of magnitude; under UV (Ultraviolet) irradiation, the conductivity of an azo polymer-carbon tube composite film is changed, and since azo molecules are in cis-trans isomerization under the UV irradiation and the molecular distance of a cis structure is reduced, higher conductivity is obtained; the conductivity of the azo polymer-carbon tube composite flexible thin film has good repeatability along with the change of irradiation, and good photo-responsitivity is expressed by the azo polymer-carbon tube composite flexible thin film; the antisotropic azo polymer / carbon tube composite thin film is expected to be applied to many fields of aerospace, organic photoelectric devices and the like.

A method is described for exfoliating a microcrystal of an anthracene derivative by irradiation with short pulses of light having a wavelength of 220-420 nm. The irradiation induces a cis-trans isomerization of the anthracene derivative in a part of the microcrystal, which leads to the separation of an outer layer having a thickness of 200-600 nm. The exfoliated microcrystal may be irradiated again with pulses of light of a same or different wavelength.

The invention discloses a photosensitive chiral macrocyclic molecule and a preparation method and application thereof, belonging to the field of preparation of photoresponsive materials. The preparation method for the photosensitive chiral macrocyclic molecule adopts the following steps: a) reacting oligomeric ethylene glycol, sodium hydroxide and p-toluenesulfonyl chloride in a tetrahydrofuran solvent in an inert atmosphere so as to obtain an intermediate 1; b) dissolving the intermediate 1, cesium carbonate and dibenzo-18-crown-6 in an N-N dimethylformamide solvent and carrying out a reaction in an inert atmosphere so as to obtain an intermediate 2; and c) dissolving the intermediate 2, chiral binaphthol compounds, cesium carbonate and dibenzo-18-crown-6 in the N-N dimethylformamide solvent and carrying out a reaction in an inert atmosphere so as to obtain a target product. The photosensitive chiral macrocyclic molecule provided by the invention has the advantages of easy synthesis, good stability, ability of selective complexation of chiral ammonium salt and capability of realizing complexation and release of chiral ammonium salt through an azo cis-trans isomerization behavior.

The invention discloses an olefin isomerism catalyst system and application thereof. The catalyst system is an organic solution formed by dissolving a ruthenium complex RuH2CO (PPh3)3 and second metal salt, the second metal salt is metal salt containing non-oxidation-reduction metal ions, a molar ratio of the ruthenium complex RuH2CO (PPh3)3 to the second metal salt is between 1:0.5 and 1:4, and concentration of the ruthenium complex RuH2CO (PPh3)3 is between 0.5 mol / L and 5 mol / L. The catalyst system can be applied in olefin double-bond isomerism, olefin cis-trans isomerism or tautomerism of olefin containing hydroxyl group, the problem that the ruthenium complex is sensitive to air and requires high temperature in a catalytic olefin isomerism system is solved, reaction conditions are mild, catalyst utilization rate is high, and the system is stable, easy to realize and low in cost.