A positive resist composition is provided comprising two onium salts, a base polymer comprising acid labile group-containing recurring units, and an organic solvent. The positive resist composition forms a pattern having PED stability and improved properties including DOF, LWR, and controlled footing profile.

A positive resist composition is provided comprising two onium salts, a base polymer comprising acid labile group-containing recurring units, and an organic solvent. The positive resist composition forms a pattern having PED stability and improved properties including DOF, LWR, and controlled footing profile.

The present disclosure relates to the field of epoxide synthesis, and particularly to a safe, environmentally friendly and controllable method for preparing cycloaliphatic diepoxides. The method comprises the steps of: mixing a diene compound, a carboxylic acid, an alkaline salt, and a solvent, and cooling; dropwise adding a hydrogen peroxide solution thereto over 1-12 h; standing for layering to obtain an underlayer of an organic phase 1, washing the organic phase 1 with a washing liquid, and standing for layering to obtain an underlayer of an organic phase 2; and purifying the organic phase 2. The reaction system of the present disclosure is simple, environmentally friendly, safe and controllable, and the production cost is low, which can meet the technical and economic requirements. The obtained cycloaliphatic diepoxides have high purity, high yield, low solvent content, low chroma and low halogen content, which are suitable for large-scale industrial production.

The invention relates to a method for the preparation of a 4,5-dihydroxyisoleucine derivative comprising the steps of asymmetric Claisen rearrangement of a Z-aminocrotyl-glycin ester and subsequent kinetic resolution of the product diastereomer mix by acylase, and subsequent Sharpless dihydroxylation of the resulting 2-amino-3-methylpent-4-enoic acid derivative.

To provide a graphene compound having an insulating property and an affinity for lithium ions. To increase the molecular weight of a substituent included in a graphene compound. To provide a graphene compound including a chain group containing an ether bond or an ester bond. To provide a graphene compound including a substituent containing one or more branches. To provide a graphene compound including a substituent including at least one of an ester bond and an amide bond.

To provide a graphene compound having an insulating property and an affinity for lithium ions. To increase the molecular weight of a substituent included in a graphene compound. To provide a graphene compound including a chain group containing an ether bond or an ester bond. To provide a graphene compound including a substituent containing one or more branches. To provide a graphene compound including a substituent including at least one of an ester bond and an amide bond.

The present disclosure provides compounds and methods for inhibiting or degrading the N-terminal domain of the androgen receptor, as well as methods for treating cancers such as prostate cancer.

The present disclosure provides compounds and methods for inhibiting or degrading the N-terminal domain of the androgen receptor, as well as methods for treating cancers such as prostate cancer.

The present invention relates to the well drilling field in petroleum industry, in particular to a nano-hybrid lubricant and method thereof, and oil-based drilling fluid. The lubricant comprises: graphite oxide and a biquaternary ammonium salt compound of which the cation part is represented by formula (1). The present invention also provides a method for preparation of the lubricant and an oil-based drilling fluid containing the lubricant. The lubricant provided in the present invention can be comprehended as a nano-hybrid material. Thus, oil-based drilling fluids that contain the lucbricant provided in the present invention have lower lubrication coefficient and excellent lubricating property without or with little negative impact on rheological property of the oil fluid, and the lubricant provided in the present invention has excellent thermostability thus suitable for use in operation at a high temperature.

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The present invention relates to the well drilling field in petroleum industry, in particular to a nano-hybrid lubricant and method thereof, and oil-based drilling fluid. The lubricant comprises: graphite oxide and a biquaternary ammonium salt compound of which the cation part is represented by formula (1). The present invention also provides a method for preparation of the lubricant and an oil-based drilling fluid containing the lubricant. The lubricant provided in the present invention can be comprehended as a nano-hybrid material. Thus, oil-based drilling fluids that contain the lucbricant provided in the present invention have lower lubrication coefficient and excellent lubricating property without or with little negative impact on rheological property of the oil fluid, and the lubricant provided in the present invention has excellent thermostability thus suitable for use in operation at a high temperature.

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