156 results about "Molecular simulation" patented technology

A method for evaluating shale reservoir stratum occurrence gas absorption quantity belongs to the technical field of petroleum exploration and development. The method can evaluate the shale reservoir stratum occurrence gas absorption quantity at different temperatures and pressures, so that the problem the cost for an on-site core analysis and isothermal adsorption experiment is high is overcome. The method comprises the following steps: 1) analyzing the component covered area of holes having different diameters in a shale sample per unit mass through a multiscale argon ion polishing and scanning electron microscope imagining method; 2) establishing a series of single-hole models of inner surfaces of holes which are covered with components and having different diameters through molecular simulation; 3) calculating the thickness and density of adsorbed-state methane located at the inner surfaces of mineral single-hole models in different temperature and pressures through molecular simulation; and 4) according to the component covered area of holes having different diameters and the thickness and density of adsorbed-state methane located at the inner surfaces of mineral single-hole models in different temperature and pressures in the shale sample, calculating the shale reservoir stratum occurrence gas absorption quantity at corresponding temperature and pressure.

The invention discloses a coarse-grained molecular dynamic method for analyzing a graphene assembly and belongs to the field of computer molecular simulation technology. The method comprises the steps that (a) a coarse-grained model of single-layer graphene is constructed; (b) a coarse-grained model of the graphene assembly is constructed according to the assembling form; (c) an interaction between coarse grains is set; and (d) coarse-grained simulation calculation is performed. Through the method, a calculation model of the graphene assembly can be easily constructed, and an actual assembly model is accurately obtained in a relaxation process. Adopted Tersoff potential function and Lennard-Jones potential function can well represent breakage and formation of chemical bonds in the assembly and accurately predict a self-assembling behavior of graphene. The adopted Tersoff potential function and Lennard-Jones potential function can accurately predict a mechanical behavior of the graphene assembly.

The invention belongs to the technical field of chemical and molecular structure information, and provides a complex system reaction access calculating system and an implementing method thereof. The calculating system comprises a molecular simulation and quantum chemistry calculating module, a molecular conformation searching module and a refined calculation and application module. A molecular structure simplified pattern reaction system is constructed, a characteristic reaction path is analyzed, and relevant key structures comprising ground states and transient states of reactions of a target reaction system are searched for. Based on a low-dimensional characteristic potential energy surface in a pattern system, a reaction network access is set up, and reaction coordinates of local minimum points and saddle points of a potential energy surface in a network are recorded; based on information of the reaction coordinates, molecule grafting restoring the pattern system (simple) to the target system (complex) is achieved. Through the molecular conformation searching technology, under the condition of characteristic coordinate restraint, a conformation set of reaction objects of the target system is searched for, and molecules in the conformation set are structurally optimized; effective ground state and transient state molecular structures of the reaction objects are collected according to the reaction characteristics of the characteristic coordinates on the reaction path.

The invention discloses a method for constructing a shale adsorption gas adsorption phase density model and calculating absolute adsorption capacity. The method comprises the following steps: regressing gas phase density into a polynomial function related to pressure; constructing a slit pore structure model of the adsorbent, and obtaining excess adsorption capacity, adsorption phase volume and absolute adsorption capacity of adsorbate in shale at different temperatures, different pressures and different pore diameters through a molecular simulation means; constructing an excess adsorption capacity model; obtaining the contribution rate of the adsorbing capacity of the adsorbate in the graphite pores to the adsorbing capacity of the shale sample under different pressure points; obtaining an adsorption phase density model of the adsorbate in the graphite slit holes and an adsorption phase density model of the adsorbate in the illite holes under different temperatures, different pressures and different hole diameters; and constructing a calculation model of the adsorbate adsorption phase density in the shale. The model is based on contribution rate, pressure, temperature and aperturedata, and the adsorption phase density calculated by the model is high in accuracy, so that the calculation accuracy of the absolute adsorption capacity is improved.

The invention discloses a method for evaluating the flowability of a polymer material by adopting a molecular simulation method. The method comprises the following steps: constructing a single chain structure of the polymer to be tested according to a repeating unit of the polymer to be tested; establishing a bulk structure model of the polymer according to the structure parameters and ingredientsof the polymer; carrying out the first relaxation of the bulk structure model, the first selection of the global optimum configuration of the NVT ensemble, the second relaxation of the configuration,the second selection of the global optimum configuration of the NPT ensemble, and the cooling annealing simulation of the NVT and NPT ensembles in order to make the configuration and density of the model fully balanced, and obtaining the second structure data; carrying out sufficient dynamic equilibrium on the second structural data to obtain the dynamic trajectory data; testing the validity of the viscosity data was tested by the stress autocorrelation function analysis of the kinetic trajectory data, and obtaining the reliable shear viscosity data of the polymer . The method of the invention can quickly, efficiently and accurately calculate the shear viscosity data of the polymer material.

The invention provides 3 novel antithrombotic quasi-peptides disclosed as general formula I, a molecular simulation method of the 3 novel antithrombotic quasi-peptides, a preparation method of the 3 novel antithrombotic quasi-peptides, inhibiting action of the 3 novel antithrombotic quasi-peptides on expression of glycoprotein IIb / IIIa and P-lectin, anti-thrombocyte aggregation action of the 3 novel antithrombotic quasi-peptides, and antithrombotic action of the 3 novel antithrombotic quasi-peptides on a rat thrombosis model. Therefore, the invention provides clinical application prospects of the 3 novel antithrombotic quasi-peptides disclosed as general formula I as an antithrombotic agent. In the general formula I, AA represents Ser or Val or Phe residue.

The present invention discloses 3D-structure of SARS-CoV Viral 3CL Protease obtained through molecular simulation. The 3D-structure is used as a drug target for screening the existing medical database CMC (Comprehensive Medicinal Chemistry, MDL Information System, Inc.), and a group of compounds which have the activity of inhibiting SARS-CoV virus 3CL Protease are found. Cinanserin was tested at molecular and viral levels, and it was found to be able to inhibit the SARS-CoV viral 3CL protease and SARS-CoV viruses. Cinanserin analogs were synthesized and tested at molecular and viral levels, they were found to be able to inhibit the SARS-CoV virus 3CL Protease and SARS-CoV viruses, and may be used for treating and / or preventing SARS-CoV virus infection.

A method for simulating the effect of an applied electric field on the formation and decomposition of methane hydrate. A methane hydrate crystal cell is established by modeling with computer simulation software, the methane hydrate crystal cell is melted at a high temperature to obtain a gas-liquid mixed phase, and then the methane hydrate crystal cell and the gas-liquid mixed phase are superposedto obtain an initial configuration; By setting simulation parameters, the stable configuration was obtained through energy minimization and pre-equilibrium simulation, and the molecular simulation was carried out by applying electric fields with different intensities and frequencies. Molecular trajectory coordinates were obtained by molecular dynamics calculation, and the molecular trajectory coordinates were analyzed by image analysis and computation. From the molecular point of view, the real-time observation of the effects of applied electric fields with different intensities and frequencies on the formation and decomposition of methane hydrate provides theoretical guidance for the practical application of electric fields in various fields of methane hydrate. The new technology can reduce the use of chemical accelerators and inhibitors of hydrate which will pollute the environment by controlling the hydrate formation and decomposition with an applied electric field.

The invention belongs to the field of analysis, relates to a quantitative analysis method for homologous / similar compounds, and particularly relates to a quantitative compound analysis method for a complicated matrix sample which does not contain a standard substance. The method comprises the following steps of: (1) selecting a series of homologous / similar compounds, and carrying out mass-spectrum quantitative methodological study and textual research on the homologous / similar compounds; (2) carrying out zero-intercept linear fitting according to established standard curves of all the compounds; (3) carrying out structural optimization on the compounds by using molecular simulation software, and calculating related molecular descriptors; (4) carrying out establishment and verification on the relationship between the structures and mass-spectrum responses of the compounds by using the molecular simulation software; (5) carrying out qualitative analysis on the complicated matrix sample by employing related mass spectrometry technologies; (6) calculating the slope coefficients of linear fit standard curves of the verified series compounds according to a structure-mass-spectrum response relationship equation established previously; and (7) obtaining the concentrations of the compounds in the complicated matrix sample by using the fit standard curves of the series compounds. Thus, the non-standard-dependence quantitative analysis is realized.

The invention provides an oil-water-solid three-phase system coarse graining force field development method, and belongs to the technical field of molecular simulation. The method can be applied to basic research related to a multi-phase system and includes the steps: 1) building an oil-water system coarse graining force field; 2) building a coarse graining solid surface through Materials Studios software, and adjusting interaction parameters of water and solid or oil and solid to obtain the relationship among the water-solid interaction parameters and the water wetness of the solid surface and the relationship among the oil-solid interaction parameters and the oil wetness of the solid surface; 3) associating the water-solid interaction parameters with the oil-solid interaction parameters based on theoretical interrelation of the water wetness and the oil wetness. The coarse graining force field is built through the relationship between the water wetness and the oil wetness by the aid of computer simulation technology, precision of the coarse graining force field is improved, development of the coarse graining force field is promoted, and the method has an important guiding significance for researching the multi-phase system.

The invention provides a molecularly imprinted polymer capable of simultaneously adsorbing multiple nitrides and a preparation method of the molecularly imprinted polymer, and belongs to the technical field of environmental pollution control chemistry. The preparation method comprises the following steps: firstly simulating an imprinting preassembly system based on a density functional theory by using a molecular simulation technology, screening out an optimal functional monomer, and preparing a molecularly imprinted adsorption material based on simulation results by virtue of seeded emulsion polymerization. An adsorbing agent synthesized by using the method provided by the invention is uniform in particle, large in specific surface area and good in adsorption kinetics; and compared with a conventional single template imprinting adsorption material, the molecularly imprinted polymer provided by the invention ensures that multiple imprinted binding sites are successfully formed, and has greater practical values.