High performance carrier stored trench bipolar transistor with dual shielding structure

We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under it.Compared with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the device.Furthermore,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also obtained.Simulation results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μm.Moreover,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,respectively.With the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,respectively.The proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON).

TEMPERING RESPONSE OF A DEFORMED LOW CARBON DUAL PHASE STRUCTURE

The low carbon dual phase structure was cold de formed first,then was tempered at 200 to 600℃.The variation in strength and ductility during tempering of the steel was investigated.It was found that a fter the de formed dual phase structure was tempered at 200 to 600℃, with the increase in the tempering temperature the tensile strength decreases rapidly;the lotal elongation remains constant at 200 to 500℃ but began to rise dramatically at a critical temperature between 500 and 600℃.However,when the non-deformed dual phase structure was tempered at the same temperature range,the tensile strength decreases and the total elongation increases continuously with the increase of temperature.It was demonstrated from TEM analysis that precipitating carbides density along the boundaries ofmartensite lath and the recrystallized grains are responsible for the tempering response ofthe de formed dual phase structure.

Bis(1-(4-(dimethylamino)benzylidene)-4-phenylthiose micarbaznato)palladium(Ⅱ):Synthesis,Crystal Structure and Its Dual Fluorescence Property

The title compound bis（1-（4-（dimethylamino）benzylidene）-4-phenylthiosemicar-bazato）-palladium（Ⅱ）（PdL2） was obtained by reacting 1-（4-（dimethylamino）benzylidene）-4-phenyl-thiosemicarbazide with dichlorobis（benzonitrile）palladium（Ⅱ） in methanol,and its structure was characterized by single-crystal X-ray diffraction.The crystal of PdL2 was obtained in dimethyl-formamide（DMF） solvent with solvent molecules involved in the cell and crystallizes in the monoclinic system,space group C2 with a = 18.485（15）,b = 7.090（5）,c = 17.595（11） ,β = 121.21（3）o,V = 1972（2） 3,Z = 2,Mr = 847.40,Dc = 1.427 g/cm3,μ = 0.624 mm-1,F（000） = 880,R = 0.0607 and wR = 0.1358.The Pd atom adopts a distorted square planar coordination geometry with two Pd-N and two Pd-S bonds.The ligand loses a proton from its tautomeric thiol form and coordinates to the Pd atom via mercapto sulfur and the imine nitrogen atom,which binds to palladium as bidentate N,S-donors forming five-membered chelate rings.The complex formed hydrogen bonding interaction with solvent DMF molecules from the hydrogen of phenylamine to the oxygen of DMF and several intramolecular hydrogen bonds.Pd（Ⅱ） perturbed ligand π-π＊ transition and metal-to-ligand charge transfer（MLCT） transition are observed in its electronic absorption spectra.The complex exhibits intraligand 1π-π＊（IL） state and MLCT state dual fluorescent emissions in organic solvent at room temperature.

Structure and Magnetic Properties of Fe-N Films Prepared by Dual Ion Beam Sputtering

Fe-N films were prepared on Si substrate by dual ion beam sputtering (DIBS). It is found that the crystal structure of the films varies from α-Fe, to ε-Fe2-3N, ε-Fe2-3N +γ-Fe4N, and finally γ'-Fe4N with the increase in substrate temperature (TS). The magnetic properties of the films were investigated by a vibrating sample magnetometer (VSM). The structure of the films is insensitive to the ratios of N2/Ar in main ion source(MIS), and is mainly influenced by the substrate temperature (Ts).

Research on the Development of Economy and Farmers' Income Growth in Heilongjiang Province

Nowadays, increasing farmers＇ income is not only related to the development of rural economy, the improvement of farmers＇ lives and countryside stability but also related to the overall situation of economy and social development. Heilongjiang is a big agricultural province, however, the increase of farmers＇ per capital net income is rather slow in the last few years. On the basis of Lewis dual economic structure theory and our province＇s actual situation, the paper proposed the concrete countermeasures to increase farmers＇ income, so as to promote the development of economy.

Superb strength and ductility balance of a Co-free medium-entropy alloy with dual heterogeneous structures

In present work,we successfully fabricated a novel Co-free non-equiatomic Ni_(46)Cr_(23)Fe_(23)Al_(4)Ti_(4)mediumentropy alloy with dual heterogeneous structures,i.e.three-levels grain structures and heterogeneous L1;precipitates.Experimental results revealed the dual heterogeneous structures lead to remarkable strength-ductility synergy properties in this Co-free medium-entropy alloy,showing high yield strength and ultimate tensile strength of~1203 MPa and~1633 MPa,respectively,remaining an excellent ductility of~28.7%.Further analyses about strengthening and deformation mechanisms indicated precipitation hardening and hetero-deformation induced hardening contribute the majority strength enhancement,meanwhile deformation-induced hierarchical stacking-faults networks,high density Lomer-Cottrell locks and microstructure features of heterogeneous grains and precipitates substantially facilitate the high work-hardening capacity and excellent tensile ductility.This work not only offers fundamental understanding of the strength and deformation mechanisms of the dual heterogeneous structural material,but also provides useful strength design strategy for low-price high performance high/medium-entropy alloys.

Fabrication of electrospun bilayer separators for lithium-sulfur batteries:A surface and structure dual modification strategy

The severe shuttle effect problem of soluble polysulfides greatly hinders the development of long-life lithium-sulfur(Li-S)batteries,which can be improved by separator modification.This study develops a bilayer separator based on an effective surface and structure dual modification strategy.This bilayer separator(named as TCNFs/SPNFs)is constructed by the integration of a carbon-based nanofiber layer(surface modification layer)with a polymer-based nanofiber layer(structure modification layer)through a facile electrospinning process.The excellent electrolyte wettability of the nanofibers accelerates lithium-ion migration,while the good electronic conductivity of the carbon layer facilitates fast electron conduction.The TiO_(2)and SiO_(2)nanoparticles embedded in the separator provide abundant active sites for immobilizing the polysulfides.Owing to these synergistic effects,this multi-functional separator helps inhibit the shuttling problem and thus enhances the active sulfur utilization.The as-prepared battery with the TCNFs/SPNFs separator delivers significantly enhanced the electrochemical performances,producing a low capacity decay rate of 0.061%per cycle at 1 C over 1000 cycles and an admirable rate capacity of 886.7 mAh g^(-1)at 2 C.Even with a high sulfur loading of 4.8 mg cm^(-2),a remarkable areal capacity of 6.0 mAh cm^(-2)is attained.This work is believed to provide a promising strategy to develop novel separators for high-performance Li-S batteries.

Analysis on the Theoretical Basis of Rural Revitalization Strategy

The rural revitalization strategy represents a quantum leap in both the theory and practice of rural development in China,and serves as a crucial solution to address the array of challenges facing rural areas.Multi-dimensionally,the rural revitalization strategy sets out the general requirements of“building rural areas with thriving businesses,pleasant living environments,good social civility,effective governance,and prosperity,”which echo the measures of new urbanization:efficient,green,humanistic,well-governed,and inclusive.Specifically,“building rural areas with prosperity”aligns with the development requirement of urban-rural dual structure theory;“building rural areas with thriving businesses”meets the development requirement of the industrial division of labor and integration theory;“building rural areas with pleasant living environments and good social civility”follows the development requirement of sustainable development theory;and“building rural areas with effective governance”tallies with the development requirement of rural governance theory.Urbanization theory,urban-rural dual structure theory,the industrial division of labor and integration theory,sustainable development theory,and rural governance theory serve as crucial theoretical references for the rural revitalization strategy,helping make clear its conceptual underpinnings.

High-entropy alloy and amorphous alloy composites fabricated by ultrasonic vibrations

We successfully fabricate high-entropy alloys and amorphous alloy composites by adopting the proposed ultrasonic vibration method.The low-stress,low-temperature method enables us to create composites that combine both amorphous and crystalline properties.Microscopic observations and computed tomography measurements indicate good bonding quality without pores or cracks in the composites.Due to the unique structure which mixes soft and rigid phases,the composite exhibits improved mechanical performance compared to that obtained from a pure single phase.Our results are promising for the manual design and fabrication of smart materials containing multiple phases and compositions.

Phase precipitation and isothermal crystallization kinetics of FeZrB amorphous alloy

The crystallization process of Fe78ZrTBls （at%） amorphous ribbon was investigated by Xray diffraction （XRD）, differential scanning calorimetry and scanning electron microscopy （SEM）. The fully amorphous structure of asquenched （Aq） ribbons was confirmed by XRD pattern. The saturation magnetization （Ms） and Curie tem perature of the Aq ribbon were measured as 124.3 （A.mZ）＆g and 305 ℃ with vibrating sample magnetometer （VSM）, respectively. When the ribbons was annealed at 550 ℃ near the first onset temperature （Txl = 564.9 ℃）, the Ms was increased by 17 %, which was caused by the formation of a dual phase structure. The isothermal crystallization kinetics and crystallization mechanism of primary ctFe phase in the dual phase structure were studied by Arrhenius and JohnsonMehlAvramiKolmogorov equations respectively. The results showed that the crystallization of Fe phase was a diffusioncontrolled surface nucleation growth process, and the nucleation rate decreased with longer crystallization time.