Abstract: Techniques are provided for controlling an output laser pulse signal of a medical device. A control device defines a time duration of capacitive discharge to a laser device. The time duration corresponds to an intended energy of the output laser pulse signal. The control device generates a plurality of sub-pulse control signals. The sub-pulse control signals define a series of capacitive discharge events of the capacitor bank. The control device modulates one or more of a sub-pulse control signal period or a sub-pulse time duration of the sub-pulse control signals to modify the capacitive discharge of the capacitor bank to the laser device during the time duration.

Abstract: The present invention relates to the field of petrochemical drilling and discloses a drilling fluid additive composition. The composition contains an emulsifier and a rheological modifier. The emulsifier is one or more of the compounds represented by Formula (1); the rheological modifier is dimer acid-organic amine copolymer, comprising structural units from the dimer acid, structural units from the alkylamine and structural units from the arylamine. The present invention further provides a drilling fluid containing the foregoing composition.

Abstract: The present subject matter relates to the drilling fluid field, and discloses a bionic drilling fluid and a method for preparation of the bionic drilling fluid. The bionic drilling fluid comprises a specific bionic wall bracing agent, a bionic shale inhibitor, a filtrate reducer, and an amphiphilic reservoir protectant, wherein, the filtrate reducer comprises microcrystalline cellulose. The bionic drilling fluid provided in the present subject matter can effectively solve the problem of well wall instability, and has great industrial application prospects.

Abstract: The present subject matter relates to the drilling fluid field, and discloses a bionic drilling fluid and a method for preparation of the bionic drilling fluid. The bionic drilling fluid comprises a specific bionic wall bracing agent, a bionic shale inhibitor, a filtrate reducer, and an amphiphilic reservoir protectant, wherein, the filtrate reducer comprises microcrystalline cellulose. The bionic drilling fluid provided in the present subject matter can effectively solve the problem of well wall instability, and has great industrial application prospects.

Abstract: The present invention relates to the field of petrochemical drilling and discloses a drilling fluid additive composition. The composition contains rheological modifier, emulsifier and tackifier. Among them, the rheological modifier is dimer acid-organic amine copolymer comprising structural units from dimer acid, structural units from alkylamine and structural units from arylamine; the tackifier is modified polysiloxane nano-particles, and the modifying group Z on the polysiloxane nano-particles is the emulsifier is one or more of the compounds represented by the following Formula (1). The present invention further provides a high temperature resistant clay-free whole-oil-based drilling fluid containing the foregoing composition. Through synergistic effect of the rheological modifier, the emulsifier and the tackifier in the composition, the present invention obtains a clay-free whole-oil-based drilling fluid with desirable suspending power and temperature resistance.

Abstract: The present subject matter relates to an amphiphilic reservoir protecting agent, including structural units denoted by the following formula (1), (2), (3) and (4). The present subject matter further provides a method for preparation of an amphiphilic reservoir protecting agent. The present subject matter further provides a drilling fluid that contains the amphiphilic reservoir protecting agent. The amphiphilic reservoir protecting agent and drilling fluid obtained in the present subject matter have high reservoir protection property and high shale inhibition property.

Abstract: The present invention discloses a bionic shale inhibitor, consisting of structural units denoted by formula (1) and structural units denoted by formula (2), wherein, the molar ratio of the structural units denoted by formula (1) to the structural units denoted by formula (2) is 0.2-6:1, and the weight-average molecular weight of the shale inhibitor is 800-4,000 g/mol. The present invention further provides a method for preparation of a bionic shale inhibitor. The present invention further provides a drilling fluid containing the bionic shale inhibitor. The bionic shale inhibitor disclosed in the present invention has high shale inhibition capability, and is environment-friendly and pollution-free.

Abstract: The present invention provides a biomimetic polymer for stabilizing wellbore, a method for preparation of the biomimetic polymer, and a drilling fluid. The polymer contains carboxymethyl chitosan that serves as a backbone and dopamine-derived groups grafted on the backbone. The polymer provided in the present invention can improve the strength of shale in the wellbore, seal the shale pores and reduce the filter loss of drilling fluid, and thereby attains an effect of stabilizing the wellbore in shale formation in drilling process.

Abstract: The present invention provides a biomimetic polymer for stabilizing wellbore, a method for preparation of the biomimetic polymer, and a drilling fluid. The polymer contains carboxymethyl chitosan that serves as a backbone and dopamine-derived groups grafted on the backbone. The polymer provided in the present invention can improve the strength of shale in the wellbore, seal the shale pores and reduce the filter loss of drilling fluid, and thereby attains an effect of stabilizing the wellbore in shale formation in drilling process.

Abstract: The present subject matter relates to an amphiphilic reservoir protecting agent, including structural units denoted by the following formula (1), (2), (3) and (4). The present subject matter further provides a method for preparation of an amphiphilic reservoir protecting agent. The present subject matter further provides a drilling fluid that contains the amphiphilic reservoir protecting agent. The amphiphilic reservoir protecting agent and drilling fluid obtained in the present subject matter have high reservoir protection property and high shale inhibition property.

Abstract: The present subject matter discloses a reservoir protecting agent composition, consisting of non-fluorescent sulfonated asphalt and a reservoir protecting agent, wherein, the reservoir protecting agent is composed of structural units denoted by the following formula (1), (2), and (3). The present subject matter further provides a drilling fluid that contains the above-mentioned reservoir protecting agent composition for middle permeability reservoirs. The present subject matter further provides an application of the drilling fluid for middle permeability reservoirs in well drilling in middle permeability reservoirs. The drilling fluid for middle permeability reservoirs disclosed in the present subject matter exhibits favorable rheology property, temperature tolerance property, and anti-collapse and protection performance when it is used in wall drilling in middle permeability reservoirs.

Abstract: The present subject matter relates to a preparation method of a wettability reversal agent, comprising: (1) adding an emulsifier into water to prepare a mixed solution of emulsifier; (2) adding compounds represented by formula (1-a), (2-a), (3-a), (4-a), (5-a), and (6-a) to the mixed solution of emulsifier to obtain a pre-emulsion, adding an initiator, and initiating a polymerization reaction. When the wettability reversal agent and reservoir protecting agent composition disclosed in the present subject matter are used in a drilling fluid, they can effectively prevent the permeation of the water phase and oil phase in the drilling fluid into the reservoir, reduce the filter loss of the drilling fluid, and thereby effectively protect the reservoir against damages from the drilling fluid.

Abstract: The present subject matter relates to a reservoir protecting agent composition, consisting of non-fluorescent sulfonated asphalt, micron-sized cellulose, and a reservoir protecting agent, wherein, the reservoir protecting agent is composed of structural units denoted by the following formula (1), formula (2), and formula (3). The present subject matter further provides a broad-spectrum drilling fluid that contains the reservoir protecting agent composition. The present subject matter further provides a use of the broad-spectrum drilling fluid in oil and gas well drilling. When the broad-spectrum drilling fluid provided in the present subject matter is used in oil and gas well drilling in reservoirs with different structures, it exhibits good rheology property, temperature tolerance, and anti-collapse and protection performance.

Abstract: The present invention provides a biomimetic polymer for stabilizing wellbore, a method for preparation of the biomimetic polymer, and a drilling fluid. The polymer contains carboxymethyl chitosan that serves as a backbone and dopamine-derived groups grafted on the backbone. The polymer provided in the present invention can improve the strength of shale in the wellbore, seal the shale pores and reduce the filter loss of drilling fluid, and thereby attains an effect of stabilizing the wellbore in shale formation in drilling process.

Abstract: The present subject matter relates to a protecting agent composition for high/ultra-high permeability reservoirs, consisting of a protecting agent and a filler, wherein, the filler comprises calcium carbonate of 600-1,000 mesh, calcium carbonate of 300-590 mesh, and calcium carbonate of 50-200 mesh at 1:(1-30):(0-40) weight ratio, and the protecting agent comprises structural units denoted by the following formulae (1), (2), and (3). The present subject matter further provides a drilling fluid containing the above-mentioned composition. The present subject matter further provides a use of the drilling fluid for drilling in high/ultra-high permeability reservoirs. The drilling fluid provided in the present subject matter has advantages including easy use, high environmental friendliness, and outstanding reservoir protection, greatly reduces the damages of drilling fluid to high/ultra-high permeability reservoirs, and brings substantial economic benefits.

Abstract: The present invention provides a biomimetic polymer for stabilizing wellbore, a method for preparation of the biomimetic polymer, and a drilling fluid. The polymer contains carboxymethyl chitosan that serves as a backbone and dopamine-derived groups grafted on the backbone. The polymer provided in the present invention can improve the strength of shale in the wellbore, seal the shale pores and reduce the filter loss of drilling fluid, and thereby attains an effect of stabilizing the wellbore in shale formation in drilling process.

Abstract: A picture archiving and communication system (PACS) includes a plurality of image diagnostic systems, a central archiving system, a coordinator, first network, second network, and means to automatically transfer medical image data generated by a modality to corresponding imaging diagnostic systems first, then the central archiving system.