Fusion power supply advances by the J-TEXT engineering team

To meet the stringent requirements of the fusion power supply for large-scale fusion devices,the J-TEXT engineering team has carried out key technology research and applications in several important directions of fusion power supply.This article presents the advances made by the J-TEXT engineering team in recent years in the following areas:(1) a high-voltage power supply for an auxiliary heating system;(2) a breakdown protection device for an auxiliary heating power supply;(3) magnetic field compatibility;(4) a high-voltage pulsed power supply for a fieldreversed configuration;(5) a large physics experimental facility control system.The research backgrounds,technical progress,test results,applications,summaries and prospects are described in detail in each part.These innovative research results and valuable engineering experience can promote the progress of fusion power supply technology,and also lay a foundation for the development of power supplies with higher parameters in the future.

Dynamic performance of linear electromagnetic actuators in a stray magnetic field:theoretical analysis and experimental verification

Linear electromagnetic actuators(LEAs) are widely used in tokamaks,but they are extremely sensitive to and are prone to fail in a high-strength stray magnetic field(SMF),which is usually a concomitant with tokamaks.In this paper,a multi-physics coupling analysis model of LEA,including magnetic field,electric circuit and mechanical motion,is proposed,and the dynamic characteristics of LEAs in SMFs are studied in detail based on the proposed model.The failure mechanism of LEAs in SMFs is revealed,and the influence of SMFs on the dynamic performance of LEAs is studied and quantified.It is shown that the failure threshold of the LEA selected in this work under the rated condition is 27 mT and 14 mT in the positive and negative direction,respectively.Under a typical SMF of 10 mT in the negative direction,the closing time of the LEA will be extended by 40%,while its opening time will be shortened by about 10%.Experimental tests are also conducted,which verify the validity of the proposed model and the analysis results.This paper provides a basis for the diamagnetic optimization design of LEA,and it is of great significance to ensure the reliable operation of the tokamak.

Acupuncture versus Western Medicine Drugs (Antidepressant) to Treat Depression

The aim of the study is to assess the beneficial effects of acupuncture compared with Western medicine in treating patientswith depression.Depression is a serious psychiatric illness that involves symptoms such as depressed or sad mood,loss ofinterest or pleasure in activities,changes in weight,difficult sleep or oversleeping,energy loss,feelings of worthlessness,psychomotorchanges,and thoughts of death or suicide.Acupuncture and Western medicine have been widely used to treat the patient with depression.The following electronic databases were searched:The Cochrane Central Register for Controlled Trials(Central),MEDLINE,EMBASE,AMED,PsycINFO,and PUBMED.The summary of this report was evaluated by using the Preferred Reporting Itemsfor Systematic Reviews and Meta-Analysis Checklist.Sixty-four journals on acupuncture,Western medicine drugs(antidepressant),and containing both in treating depression were identified and included in this review.In term of Western medicine,antidepressant may helpthe ego function in short term,and for long-term using,it may cause the patient to become addictive toward the drug.Acupuncture is relativelysafe to use and proven significantly effective to treat the depression and less side effect for long term used by the patient.Currentevidence from this summary literature review shows that acupuncture and Western medicine(antidepressant)drugs can treat depression.However,acupuncture therapies almost give none of side effect compared to antidepressant,and every patient with depression can try acupuncture notexcluding the pregnant woman.

Statistical characteristics and mechanism analysis of adhered particle on surface under strong electric field

Insulators on high-voltage Uansmission lines are almost the only man-made structures on the Earth's surface intended for long-term operation under strong electric fields. After samples of natural contaminant particles were collected from insulator surfaces in China, it was found that the particle diameter distribution (PDD) was mainly concentrated in the 5-50 μm range. To analyze the statistical characteristics of these particles, this work studies the physical processes of particle collision and adhesion using the theories of hydrodynamics and collision dynamics. The physical model considers coupling of the fluid field and the electric field, introduces an adhesion criterion, and establishes a particle and surface collision model. The effects of relative humidity, wind speed, aerodynamic shape, electric field type, and electric field strength on particle adhesion were analyzed. The results show that the relative humidity and wind speed have very significant effects and the influences of the electric field type and the electric field strength are obvious, but the in fluence of the aerodynamic shape is relatively weak. The simulation results support the statistical characteristics determined in this work. The physical model established here provides reference values for study of the adhesion characteristics of particles on surfaces under electric fields.