The Dynamic Volt-Ampere Characteristics of a Vacuum Arc at Intermediate-Frequency Under a Transverse Magnetic Field

In this study, the changes of a vacuum arc＇s appearance were observed and the volt-ampere characteristics of the vacuum arc at intermediate frequency were analyzed under a transverse magnetic field （TMF）. The TMF and phase shift time were calculated by using the TMF contact model and the large phase shift of the magnetic field at a higher frequency was conductive to the dispersion process of residual plasma. The arc velocity was higher at 800 Hz than at 400 Hz. It can be inferred that TMF will encourage arc movement at 800 Hz. Moreover, the arc movement has an impact on the arc voltage. Because of the increasing length of the arc column with a high arc velocity, the elongated arc causes the arc voltage to increase. Specifically, the volt-ampere characteristics of the vacuum arc are divided into three stages in this paper. The higher the frequency, the greater the initial rate of rise in the arc voltage and the larger the area surrounded by arc volt-ampere characteristics. The correlations between the arc voltage and the amplitude and frequency of the current are also presented.

VOLT-AMPERE CHARACTERISTICS OF CIS-POLY(PHENYL ACETYLENE)

The volt-ampere (Ⅰ-Ⅴ) characteristics of the c/s-poly (phenyl acetylene) (PPA) of cis-transoidal structure has been studied in the temperature range of 253-288K. An ITO/ PPA/ Au sandwich configuration was used for the measurements. Under an applied field of less than 10~5V/ cm it showed ohmic behavior, while the space charge limited current (SCLC) was observed at applied fields above 5×10~5V/ cm. In the ohmic region a conductivity of 1.37×10^(-16)S/ cm was obtained at room temperature with an activation energy of 0.5eV. These data indicate that the conduction is not intrinsic one but is the result of thermal release of trapped carriers. In fact the data in the SCLC region treated according to the theory for a single Gaussian distribution of traps gave a mean trap energy of 0.48 eV with a half-width of 0.4 eV and a total density of trapping states of 5×10^(16)/cm^3.

Volt-ampere characteristics of a nitrogen DC plasma arc with anode melting

The characteristics of a nitrogen arc using a graphite cathode and a melting anode in a pilot-scale plasma furnace are investigated. The voltage is examined as a function of current and apparent plasma length. The voltage increases non-linearly with the increase of apparent plasma length, with the current fixed. The experimental data so obtained are compared with the predictions of the Bowman model for the electric arc, and with numerical simulations as well. The level of agreement between the experimental data at the melting anode and the numerical predictions confirms the suitability of the proposed the Bowman model. These characteristics are relevant to the engineering design and evaluation of a DC plasma furnace and reactor for the treatment of hazardous fly ash waste.

Construction of a broadband impedance spectrum and synchronous DC voltammetry measurement system for solar cells

The current impedance spectroscopy measurement techniques face difficulties in diagnosing solar cell faults due to issues such as cost,complexity,and accuracy.Therefore,a novel system was developed for precise broadband impedance spectrum measurement of solar cells,which was composed of an oscilloscope,a signal generator,and a sampling resistor.The results demonstrate concurrent accurate measurement of the impedance spectrum(50 Hz-0.1 MHz)and direct current voltametric characteristics.Comparative analysis with Keithley 2450 data yields a global relative error of approximately 6.70%,affirming the accuracy.Among excitation signals(sine,square,triangle,pulse waves),sine wave input yields the most accurate data,with a root mean square error of approximately 13.3016 and a global relative error of approximately 4.25%compared to theoretical data.Elevating reference resistance expands the half circle in the impedance spectrum.Proximity of reference resistance to that of the solar cell enhances the accuracy by mitigating line resistance influence.Measurement error is lower in high-frequency regions due to a higher signal-to-noise ratio.

Capsule Development Characters at Different Positions of Sesame(Sesamum indicum)

[Objective] This study aimed to explore the capsule development at differ-ent positions of sesame （Sesamum indicum）. [Method] The number of flowers and capsules at lower part （below the 8th node from the bottom）, middle part （at 9th-20th nodes from the bottom） and upper part （above the 20th node） of sesame plants （Zhengzhi 98N09） was counted. The length, width, fresh weight of the capsules, fresh and dry weight of the seeds, and the dry weight of the capsule shel s at dif-ferent growth stages were measured. [Result] From the bottom to the top of sesame plants, the numbers of flowers and capsules at each node showed a trend of first increasing and then decreasing. The 15th and the 12th node had the maxi-mum flower number （9.3 flowers per node on average） and the maximum capsule number （4.2 capsules per node on average）, respectively. The middle nodes had the highest capsule setting rate, up to 45.1%, fol owed by that at upper nodes, 30.1%, and the capsule setting rate at lower nodes was the smal est, only 25.0%. The capsule length, width, fresh weight, seed fresh weight, dry weight and capsule shel dry weight at middle part were higher than that at lower and upper part. Moreover, grain fil ing rates of the lower, middle and upper capsules were 0.003 5, 0.004 4 and 0.003 0 g/（capsule·d）. It suggests that the substances gave priority to supply the middle capsules during the development of capsules. [Conclusion] This study wil provide theoretical basis for the cultivation of high-yielding sesame.

Numerical Analysis of Interaction Between Single-Pulse Laser-Induced Plasma and Bow Shock in a Supersonic Flow

The interaction of laser-induced plasma and bow shock over a blunt body is inves- tigated numerically in an M∞ =6.5 supersonic flow. A ray-tracing method is used for simulating the process of laser focusing. The gas located at the focused zone is ionized and broken down and transformed into plasma. In a supersonic flow the plasma moves downstream and begins to interact with the bow shock when it approaches the surface of the blunt body. The parameters of flowfield and blunt body surface are changed due to the interaction. By analyzing phenomena occurring in the complex unsteady flowfield during the interaction in detail, we can better under- stand the change of pressure on the blunt body surface and the mechanism of drag reduction by laser energy deposition. The results show that the bow shock is changed into an oblique shock due to the interaction of the laser-induced low-density zone with the bow shock, so the wave drag of the blunt body is reduced.

Experimental study on the jet characteristics of a steam plasma torch

Thermal steam plasma jet is promising for applications in environmental industries due to its distinctive characteristics of high enthalpy and high chemical reactivity. However, the performance of the steam plasma torch for its generation is limited by the problems of the large arc voltage fluctuation and serious erosion of the electrodes. In this study, a gas-stabilized steam plasma torch which can operate continuously and stably was designed. Experiments were conducted to reveal the effect of the different working parameters, including the anode diameter, the cooling water temperature, the arc current and the steam flow rate, on its Volt-Ampere characteristics, arc voltage fluctuation, thermal efficiency, jet characteristics and electrodes erosion. Results showed that the use of hot water to cool the electrodes can effectively prevent the condensation of steam on the inner wall of the electrodes, thus significantly reducing the arc voltage fluctuations and electrodes erosion. This is crucial for increasing the working life of the electrodes and ensuring long-term stability of the steam plasma torch. In addition, suitable anode diameter can greatly reduce the arc voltage fluctuation of the steam plasma torch and effectively improve the stability of the steam plasma jet. Furthermore, high arc current can effectively reduce the fluctuations of the arc voltage and increase the length and the volume of the steam plasma jet. Finally, using steam as the plasma forming gas can achieve higher thermal efficiency compared to air. An ideal thermal efficiency can be achieved by properly reducing the arc current and increasing the steam flow rate.

Chinese Enrichment and Development of Marxist Concept of Democracy in the New Era

Since the Eighteenth National Congress of the Communist Party of China,Chinese communists,re-presented by President Xi Jinping,have innovated Marxist Concept of Democracy base on Chinese history,culture and conditions. On the basis of inheriting Marxist thought of the inner prescriptions of "people's democracy",they fur-ther expanded the connotation and extension of "rule by the people",developed the contents of the electoral democ-racy and consultative democracy in China.,enriched the concrete requirements of the democratic realization condi-tions from the aspects of economic foundation,intellectual support and the guarantee of the rule of law,and a new ex-ploration is made on the development of China's democratic political system from the aspects of Party's leadership and operation supervision.

Spin-dependent transport induced by magnetization in zigzag graphene nanoribbons coupled to one-dimensional leads

We study spin transport in a zigzag graphene nanoribbon sample with two ferromagnetic strips deposited on the two sides of the ribbon. A tight-binding Hamiltonian was adopted to describe the sample connected to two one- dimensional leads. Our theoretical study shows that the resonance peaks of conductance for the spin-up and spin-down electrons are separated for the parallel configuration of the ferromagnetic strips, while they are not separated for the case of antiparallel configuration. This means that giant magnetoresistance can be produced at particular energies by altering the configurations of the ferromagnetic strips, and the device can be designed as a spin filter.

Electrical and Optical Characteristics of Electrodeless Lamp

In order to study the methods to enhance the efficacy of electrodeless lamp,volt-ampere characteristics,illuminance and emission spectrum have been investigated in home-built electrodeless lamp experimental system with an electrodeless lamp in shape like QL 85 lamp.The results show that lamp current increases as lamp voltage increases in non-discharge,the current decreases first and then increases as the voltage increases in discharge.The illuminance of electrodeless lamp increases linearly with discharge power increasing,and it decreases linearly with power decreasing.The emission spectrum is different for different bulb and lighting time.The spectrum of Ar 811.5 nm,76.5 nm,750.4 nm and Hg 313.2 nm decrease with lighting time.While the intensity of Hg 407.8 nm increases with lighting time.

A Study on Helium Glow Discharge Cleaning in the HL-1M Tokamak

Based on the principle of ion-bombarded reemission and sputtering desorption, the Glow Discharge Cleaning with helium (GDC(He)) is an effective method for controlling the recycle of H on the chamber wall, Carbon(C), Oxygen(O) impurity and improving the wall conditioning in HL-lM tokamak. It is characterized by simplicity without magnet and safety, compared with Taylor Discharge Cleaning (TDC), Alternating current glow discharge Cleaning (AC), Electron Cyclotron Resonance-Discharge Cleaning (ECR-DC). Compared with bake-out degassing, the wall has a higher degassing rate during GDC(He) and a lower impurity concentration in vacuum chambers after GDC(He). Cleaning patterns have been developed dominantly for de-oxidization, de-carbonization and de-hydrogenization. The cleaning parameters for H recycle on the wall are also presented. This paper mainly describes the GDC system along with its parameters, breakdown voltage, volt-ampere characteristic, the range of operation safe and suitable cleaning patterns in the HL-lM tokamak, finally concluding with some suggestions on HL-2A GDC.

Current dependence coefficient determination for different DC standard resistors measurements based on Ⅴ-Ⅰ method

Current dependence and stability of the measured resistance value are very important for the accurate measurement of DC standard resistor. In this paper, the volt-ampere （V-I） measurement method has been applied to study the current depend-ence of four different types of standard resistors. Diverse values are obtained through the investigation of their stability at dif-ferent currents. Therefore, the current dependence coefficient （CDC） can be determined for each one of the studied resistors. Research shows CDC depends on the applied current value, the measurement time and the resistor type, as clearly demonstra-ted in this research.

基于AMESim的喷浆机械手负载敏感技术的研究（英文）

综述了喷浆机械手的工作原理,阐述了负载敏感技术的构成和工作原理,建立了负载敏感系统的AMESim模型,通过对系统的仿真研究,分析了负载敏感系统的压力及流量特性,为了解负载敏感系统的优点提供了数据支持,并为喷浆机械手的设计及发展提供了理论依据。

Decomposition and embedment of trajectories after explosion for a birth and death process

Let X = X(t),t < σ (σ is lifespan) be a birth and death process with explosion whose characteristic triple is (α, C, D). For a set $\bar M \subset \bar E = \left\{ {0, 1, 2, \cdots , \infty } \right\}$ , reserving the trajectories before the first explosion time τ and decomposing the trajectories after τ for X according to $\bar M$ we obtain a new birth and death process $_{\bar M} X = \left\{ {_{\bar M} X\left( t \right), t < _{\bar M} \tau } \right\}$ . We calculate the average lifetime after τ for $_{\bar M} X$ and corresponding characteristic triple $\left( {_{\bar M} \alpha , _{\bar M} C, _{\bar M} D} \right)_{\bar M} X$ of $_{\bar M} X$ in terms of (α,C, D) and $\bar M$ . This means that a lot of given birth and death processes can be embedded in one and the same birth and death process. If $k \in \bar E$ and $\bar M = \left\{ k \right\}$ , we decompose X into $_k X, k \in \bar E$ .

Experimental investigation on phase transformation type micropump

The phase transformation type micropump without moving parts was experimentally studied in this note. To analyze the pumping mechanism of the micropump, a simplified physical model was presented. The experimental results indicate that the pump characteristic is mainly dependent on the heating and cooling conditions. For a given system, there exist an optimal combination of heating current and switch time with which the flow rate reaches maximum. Comparing with the natural cooling, the forced con-vective cooling needs larger heating current to obtain the same flow rate. In our experiments, the maximum flow rate is 33μL/min when the inner diameter of the micropump is 200μm, and the maximum pumping pressure reaches over 20 kPa. The theoretical analysis shows that the pumping mechanism of the micropump mainly lies in the large density difference between liquid and gas phases and the effect of gas chocking.

Influence of inhabitant background on the physical changes of Banjarese houses： A case study in Kuin Utara settlement, Banjarmasin, Indonesia

The disappearance of vernacutar buitdings is a common phenomenon worldwide and in Indonesia. The Banjarese house, a type of Indonesian vernacutar architecture, is a typicat riverside dwetling that shows the strong relationship between the river and the inhabitants. In view of the number of Banjarese houses facing degradation as a riverside type of vernacutar architecture, a study is necessary. The characteristics of the inhabitants must be considered when observing the condition of the remaining houses. Therefore, this study aims to investigate the influence of inhabitant background on the physicat changes of Banjarese houses for future revitatization. A research was conducted in the embryo of Banjarmasin atong the Kuin riverside setttement in Kuin Utara sub-district through a door-to-door survey with a questionnaire. The exploration indicates the following： （1） the original form of art remaining houses has been attered, （2） most of the inhabitants are ctassified as a tow-income society, （3） the different characteristics of the present inhabitants change the physicat condition of houses, （4） the retationship of the current house condition to the socio-cutture and economy of the inhabitants prays a prominent rote in revitatizing Banjarese houses as a vatuabte asset.

Improving acoustical characteristics of a Gothic cathedral using simple public address system： A case study of Nlyeong-dong Cathedral in Seoul, Korea

In the present study, improving acoustical characteristics of a Gothic cathedral （Myeong-dong Cathedral, which is the first built Western Gothic-style architecture in Korea） using simple public address system were investigated. Acoustical measurements were conducted at 11 selected points inside the cathedral and seven acoustical parameters were calculated： sound pressure level （SPL）： 64.6 dBA （the measurement value with regard to the omni-directional speaker sound source）; 74.5 dBA （the measurement value with regard to the public address speaker sound source）, early decay time （EDT）： 4.04 s; 3.76 s, reverberation time （RT6o）： 3.58 s; 3.89 s, clarity （Cso）： -6.2 dB; -2.8 dB, definition （D50）： 18%; 29%, initial time delay gap （ITDG）： 47 ms; 23 ms, and rapid speech transmission index （RASTI）： 32%; 42%. Parameters showed that the acoustical characteristics of a typical Gothic cathedral include rich reverberation and diffusive sound fields. Meanwhile, there was improved speech intelligibility when using simple public address system. Based on subjective evaluation, there was overall satisfaction with voice and music recognition and the highest satisfaction with clarity with respect to voice recognition and with reverberation with respect to music recognition. This is a good solution of optimized acoustic environment through harmony between natural reverberation and reinforced clarity using simple public address system.

Experimental research on the mechanism of non-monotonic characteristic between curing temperature and mechanical behaviors of Kevlar/epoxy composite

An experimental procedure is conducted to investigate the mechanism of the non-monotonic characteristic between curing temperature and mechanical behaviors of the Kevlar/epoxy composite in macro and micro levels. Different specimens are fabricated at four different curing temperatures and tested with ±45° off-axis tensile loading on a universal test machine coupled with digital image correlation(DIC). Moreover, the environmental scanning electron microscope(SEM) was used to obtain the micrographs and reveal their mechanism. The tested results show that the tensile mechanical behaviors are sensitive to the curing temperature and the relationship is non-monotonic. Also, as the temperature increases, the thicknesses of the specimens are significantly enlarged. By analyzing the SEM micrographs of the matrix grooves in the damage zone and DIC strain contours, it is concluded that the non-monotonic relationship is dominated by the properties of the Kevlar/epoxy interfaces and deformation of the distorted fibers.

Imitation of the characteristics of the wind turbine based on DC motor

This paper analyzed the operating principles and power and torque characteristics of the wind turbine and the direct current motor (DC motor), and investigated the operating characteristics of the wind turbine compared to that of the DC motor. The torque imitation scheme, which has good performance and high feasibility, together with the whole wind turbine imitation system, was provided. The wind turbine imitation system includes not only a hardware platform composed of PC, data-collection board and thyristor-based velocity-regulator, but also monitor software of wind turbine imitation. The experimental results of different occasions verify the correctness and feasibility of the wind turbine imitation scheme proposed in this paper, which provided a valid idea for wind turbine imitation and investigation of wind power generation techniques in the laboratory.