Computational Investigation on the Surface Electronic Density, Morphology and Detonation Property of 1,1-Diamino-2,2-dinitroethylene (FOX-7) Crystal

The present study constructed and optimized FOX-7 crystal using a novel technique including grand canonical monte carlo （GCMC）, density functional theory （DFT） and molecular dynamics （MD） methods. Therein, the crystal density, atomic and electronic actions were considered. The results showed that the 1.96 g.cm-3 FOX-7 crystal has the highest stability and detonation properties, such as the total crystal energy, surface electronic density, friction sensitivity, detonation pressure, and so on. These results are close to the experimental data.

Single-event response of the SiGe HBT in TCAD simulations and laser microbeam experiment

In this paper the single-event responses of the silicon germanium heterojunction bipolar transistors(SiGe HBTs) are investigated by TCAD simulations and laser microbeam experiment. A three-dimensional(3D) simulation model is established, the single event effect(SEE) simulation is further carried out on the basis of Si Ge HBT devices, and then, together with the laser microbeam test, the charge collection behaviors are analyzed, including the single event transient(SET) induced transient terminal currents, and the sensitive area of SEE charge collection. The simulations and experimental results are discussed in detail and it is demonstrated that the nature of the current transient is controlled by the behaviors of the collector–substrate(C/S) junction and charge collection by sensitive electrodes, thereby giving out the sensitive area and electrode of SiGe HBT in SEE.

Laser-Induced Single Event Transients in Local Oxidation of Silicon and Deep Trench Isolation Silicon-Germanium Heterojunction Bipolar Transistors

We present a study on the single event transient （SET） induced by a pulsed laser in different silicon-germanium （SiGe） heterojunction bipolar transistors （HBTs） with the structure of local oxidation of silicon （LOCOS） and deep trench isolation （DTI）. The experimental results are discussed in detail and it is demonstrated that a SiGe HBT with the structure of LOCOS is more sensitive than the DTI SiGe HBT in the SET. Because of the limitation of the DTI structure, the charge collection of diffusion in the DTI SiGe HBT is less than that of the LOCOS SiGe HBT. The SET sensitive area of the LOCOS SiGe HBT is located in the eollector-substrate （C/S） junction, while the sensitive area of the DTI SiGe HBT is located near to the collector electrodes.

Zincophilic Ti_(3)C_(2)Cl_(2)MXene and anti-corrosive Cu NPs for synergistically regulated deposition of dendrite-free Zn metal anode

Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the anodes.Herein,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin coating.The CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn deposition.In addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and HER.Therefore,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/plating.The full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes.

MOF-derived Se doped MnS/Ti_(3)C_(2)T_(x) as cathode and Zn-Ti_(3)C_(2)T_(x) membrane as anode for rocking-chair zinc-ion battery

Mn-based zinc ion battery has the advantages of low cost and high performance,which makes it the promising energy storage system.However,the poor conductivity and the agglomeration in the synthesis process of manganese-based materials restrict the performance of batteries.Herein,the Se-doped MnS/Ti_(3)C_(2)T_(x)(Se-MnS/Ti_(3)C_(2)T_(x))composite material derived from Mn-based metal-organic framework is reported.Electrochemical tests show that Se-doped could generate S defects and enhance the electrochemical activity of MnS.At the same time,the introduction of Ti_(3)C_(2)T_(x) substrate is conducive to exposing more sulfur defects and improving the utilization rate of defects.In the mechanism study,it is found that Se-MnS/Ti_(3)C_(2)T_(x) is transformed into S/Se co-doped Mn3O_(4) at the first charge,which innovatively elucidated the behavior of S/Se during activation.In the electrochemical performance test,the specific capacity can reach 74.7 mAh·g^(-1) at 5.0 A·g^(-1).In addition,the Zn-Ti_(3)C_(2)T_(x) membrane electrode is prepared by vacuum filtration as the zinc-poor anode,which is assembled into the rocking chair full battery to avoid dendrite growth and exhibit excellent rate performance.The addition of Zn2+weakens the electrostatic repulsion between the interlayers of MXene,and the formation of the folded morphology aids the penetration of the electrolyte.At 1.0 A·g^(-1),the capacity can reach 50.6 mAh·g^(-1).This work is helpful to promote the research and development of the reaction mechanism of manganese based rocking chair batteries.

Room-Temperature Annealing of 1 MeV Electron Irradiated Lattice Matched In0.53Ga0.47As/InP Multiple Quantum Wells

Long-term room-temperature annealing effects of InGaAs/InP quantum wells with different wells （namely triple wells and five wells embedded） and bulk InCaAs are investigated after high energy electron irradiation. It is observed that the photoluminescence （PL） intensity of bulk InGaAs materials is enhanced after low dose electron irradiation and the PL intensity for all the three samples is degraded dramatically when the electron dose is relatively high. With respect to the room-temperature annealing, we find that the PL intensity for both samples recovers relatively fast at the initial stage. The PL performance of multiple quantum-well samples shows better recovery after irradiation compared with the results of bulk InGaAs materials. Meanwhile, the recovery speed factors of multiple quantum-well samples are relatively faster than those of the bulk InGaAs materials as well. We infer that the recovery difference between the quantum-well materials and bulk materials originates from the fact that the radiation induced defects are confined in the quantum wells as a consequence of the free energy barrier between the In0.53Ga0.47 As wells and InP barrier layers.

A CaS:Ce,Sm-based dosimeter for online dosimetry measurement

A film dosimeter based on optically stimulated luminescence (OSL) material of CaS:Ce,Sm was developed for online irradiation dosimetry measurement.The stimulation is provided by a laser with a wavelength of 980 nm,and the OSL luminescenceis collected by a photodiode.Using 60Co γ-rays,we investigated the dosimetry characteristic of the dosimeter at different dose rates and total doses.The real-time detection results showed that the OSL signals versus total ionizing dose exhibited a good linearity in a dose range of 0.1-185 Gy.

A Comparison Study of Sinterability and Electrical Properties for Microwave and Conventional Sintered Mn_(0.43)Ni_(0.9)CuFe_(0.67)O_4 Ceramics

In this paper, a quaternary system of Mn0.43Ni0.9CuFe0.67O4 negative temperature coefficient （NTC） thermistor ceramic prepared by solid/solid reaction was sintered by microwave and conventional method, respectively. To characterize the sinterability of the samples, the densification parameter, porosity and grain size distribution of the bulk were determined. The crystal structure, phase compositions, morphology and impedance of the samples were analyzed by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy-dispersive spectroscopy （EDS） and impedance analysis. The experimental results confirmed that the sinterability and electrical properties of ceramics were homogenously improved by microwave sintering.

Growth Mechanism,Modified Morphology and Optical Properties of Coral-like BaTiO_3 Architecture through CTAB Assisted Synthesis

Three-dimensional hierarchical structure coral-like BaTiO3 nanoparticles have been self-assembled by a facile one step hydrothermal method. Cetyltrimethyl ammonium bromide(CTAB),Ba(OH)2·8H2O and tetrabutyl titanate have been used as precursors. The prepared Ba TiO3 exhibits cubic perovskite phase at room temperature,and the coral-like architecture is a micro-nano hiberarchy consisted of dendrimer-like structure and trunk-like structure. By adjusting the hydrothermal duration and the precursor substances,a surfactant induced mechanism is proposed to understand the self-assembly process. UV-vis measurement demonstrates that the as-prepared Ba TiO3 nanoparticles exhibit dozens of times overwhelming absorptive character compared to the ordinary nanospheres at ultraviolet band,which is benefited from the coral-like porous framework. Moreover,halogen anions( F,Cl,Br,and I) have been chosen to adjust the coral-like Ba TiO3 physical properties. Results show the halogen doping produces distinct modulation effect on the grain size,UV-vis absorbance and photoluminescence properties of the materials. The coral-like BaTiO3 nanoparticle and its halogen modified ramifications offer significant opportunities to develop nano-laser devices,photon detectors,photocatalyst based on BaTiO3 perovskite materials.

Preparation and thermal-sensitive characteristic of copper doped n-type silicon material

Copper doped n-type single-crystal silicon materials are prepared by a high temperature diffusion process. The electrical and thermal-sensitive characteristic of materials is investigated under different experimental conditions. The results show that the maximum resistivity of 46.2 Ω·cm is obtained when the sample is treated at 1200℃ for 2 h with the surface concentration of the copper dopant source being 1.83×10^7mol/cm^2. The copper doped n-type silicon material presents a negative temperature-sensitive characteristic and the B values are about 3010–4130 K.

Radiation Effects Due to 3 MeV Proton Irradiations on Back-Side Illuminated CMOS Image Sensors

Benefitting from the higher quantum efficiency and sensitivity compared with the front-side illumination（FSI）CMOS image sensors（CISs）, backside illumination（BSI） CMOS image sensors tend to replace CCDs and FSI CISs for space applications. However, the radiation damage effects and mechanisms of BSI CISs in the radiation environment are not well understood. We provide radiation effects due to 3MeV proton irradiations of BSI CISs dedicated to imaging by the analyses of mean dark current increase, dark current nonuniformity and full well capacity in pixel arrays and isolated photodiodes. Additionally, the present annealing certifies the radiationinduced defects, which are responsible for the parameter degradations in BSI CISs.

Synthesis and optical properties of novel Gd^(3+)-doped BaZn_(2)(PO_(4))_(2)glass-ceramics for radiation detection applications

45 P_(2)O_(5)-15 BaO-25 ZnO-15 B2O_(3)glasses doped with different concentrations(0 mol%,0.1 mol%,0.25 mol%,0.5 mol%,and 0.75 mol%)of Gd^(3+)were prepared by a melt-quenching method and treated to fabricate glass-ceramics containing BaZn_(2)(PO_(4))_(2)crystals by controllable crystallization.The structural,optical,and dosimetric properties were investigated.FTIR spectra indicate that the glasses are composed of[PO_(4)],[BO_(3)],and[BO_(4)]basic structural units.The XRD pattern analysis indicates that the samples contain BaZn_(2)(PO_(4))_(2)crystals.In the photoluminesce nce(PL)spectra,two emission bands are observed at 307 and 313 nm due to the^(6)P_(5/2)→^(8)S_(7/2)and^(6)P_(7/2)→^(8)S_(7/2)transitions of Gd^(3+),respectively.The OSL dosimetric properties of glass-ceramics were studied further under beta radiation of90Sr.The optimal Gd^(3+)doping concentration of 0.5 mol%was determined.The fading of the OSL signal shows that the CW-OSL signal of Gd^(3+)-doped BaZn_(2)(PO_(4))_(2)glass-ceramics decays by about 58.95%within120 h,and the intensity remains stable thereafter.The thermoluminescence(TL)curve has three peaks at 164,240,and 344℃.Minimum detectable dose(MDD)of the 0.5 mol%Gd^(3+)-doped BaZn_(2)(PO_(4))_(2)glass-ceramics was calculated as 0.675 mGy.The samples also exhibit good signal reusability and a broad linear dose-response range(0.3-500 Gy).Results show the excellent dosimetric properties of Gd^(3+)-doped BaZn_(2)(PO_(4))_(2)glass-ceramics and their potential application in radiation dosimetry.

Enhanced aging and thermal shock performance of Mn_(1.95-x)Co_(0.21)Ni_(0.84)Sr_(x)O_(4) NTC ceramics

The Mn_(1.95-x)Co_(0.21)Ni_(0.84)Sr_(x)O_(4)(MCNS)(0≤x≤0.15)based negative temperature coefficient(NTC)materials are prepared by co-precipitation method.The replacement of Mn by Sr plays a critical role in controlling the lattice parameter,relative density,microstructure,and electrical properties.The lattice parameter and relative density increase with the increase of Sr content.A small amount of Sr restrains the grain growth and increases the bulk density.Moreover,the room resistivityρ25,material constant B25/50,activation energy Ea,and temperature coefficientαvalues of MCNS ceramics are influenced by the Sr content and ranged in 1535.0–2053.6Ω·cm,3654–3709 K,0.3149–0.3197 eV,and(–4.173%)–(–4.111%),respectively.The X-ray photoelectron spectroscopy(XPS)results explain the transformation of MCNS ceramics from n-to p-type semiconductors.The conduction could arise from the hopping polaron between Mn3+/Mn4+and Co^(2+)/Co^(3+) in the octahedral sites.The impedance data analysis also discusses the conduction mechanism of the MCNS ceramic,whereas grain resistance dominates the whole resistance of the samples.Furthermore,the aging coefficient(△R/R)of MCNS ceramics is found to be<0.2%,which indicates the stable distribution of cations in the spinel.Finally,the MCNS ceramics demonstrate excellent thermal durability with<1.3%of resistance shift after 100 thermal shock cycles.

Double humps and radiation effects of SOI NMOSFET

Radiation experiments have been carried out with a SOI NMOSFET.The behavior of double humps was studied under irradiation.The characterization of the hump was demonstrated.The results have shown that the shape of the hump changed along with the total dose and the reason for this was analyzed.In addition,the coupling effect of the back-gate transistor was more important for the main transistor than the parasitic transistor.

Coexistence of nontrivial topological properties and strong ferromagnetic fluctuations in quasi-one-dimensional A_(2)Cr_(3)As_(3)

Superconductivity in crystals without inversion symmetry has received extensive attention due to its unconventional pairing and possible nontrivial topological properties.Using first-principles calculations,we systemically study the electronic structure of noncentrosymmetric superconductors A_(2)Cr_(3)As_(3)(A=Na,K,Rb,and Cs).

新的非线性光学材料K7MRE2B15O30（M=Ca andBa,RE=La and Bi）的合成、表征和理论分析（英文）

本文采用高温熔液法合成了三种新型复合硼酸盐化合物K7CaBi2B15O30、K7CaLa2B15O30和K7BaBi2B15O30. K7CaLa2B15O30和K7CaBi2B15O30结晶于三方手性空间群R32中,K7BaBi2B15O30结晶于非中心对称正交极性空间群Pca21.这三个化合物具有相似的三维晶体结构,由孤立的B5O10基团和LaO6或BiO6八面体组成,K^+、Ca^2+、Ba^2+阳离子填充于空隙中以保持电荷平衡.根据我们的调研,在K7MⅡRE2B15O30体系内(MⅡ=Ca,Sr,Ba,Zn,Cd,Pb,K/RE0.5;RE=Sc,Y,La,Gd,Lu,Bi),K7BaBi2B15O30是唯一一个结晶于不同空间群的化合物,其丰富了硼酸盐的结构化学.详细的结构分析表明,碱土金属阳离子的尺寸和配位数的差异是导致结构变化的主要原因.此外,UVVis-NIR光谱分析和倍频效应(SHG)测试表明K7CaBi2B15O30具有较短的截止边(大约282 nm)和适中的倍频效应(约0.6×KDP).我们还进行了热重差热和红外光谱的测试.为了更好地理解上述化合物的结构性能关系,我们还进行了第一性原理计算.

Synthesis and luminescence in LiMgPO_4:Tb,Sm,B phosphors with possible applications in real-time dosimetry

The objective of this work was to develop possible materials for optically stimulated luminescence （OSL） dosimetric applications in real-time measurement. A novel material of LiMgPO4：Tb,Sm,B was prepared by solid-state diffusion method at 900 oC. The structure and optical properties of these phosphors were characterized by X-ray diffraction, fluorescence spectro？photometer, and OSL reader. The results showed that the full discrimination between the stimulation and emission spectra made them very fit for the optic-fibre dosimetry. The OSL vs. dose response was linear in the dose range of 0.1 to 216 Gy. It also showed a significant improvement in the stimulation time compared with LiMgPO4：Tb,B. Hence, the phosphor could be used in the real-time dosimeter based on the OSL technology for medical monitoring as well as for environmental dosimetry and space dosimetry.

Optically stimulated luminescence of Dy^3+-doped NaCaPO4 glass-ceramics

Dy^3+-doped glass-ceramics containing NaCaPO4 crystals were successfully fabricated by heat treatment at base glass,and the luminescence properties were investigated for potential applications in radiation measurements.The photo luminescence(PL)excitation and emission spectra exhibit transitions related to Dy^3+ions corresponding to the strongest excitation and emission wavelengths at 351 and 575 nm,respectively.The CW-OSL properties as a function of dopant concentration,pre-heating temperature,pre-heating time and signal fading were investigated.The most appropriate Dy^3+ion concentration was found to be 0.25 mol%.The TL glow curves have a broad peak feature peaking at 195±5℃.The fading of the OSL signal would keep stable in five days with the intensity value of about 76.11%.The samples also exhibit good signal reusability and a broad linear dose response range(0.02-1000 Gy).

Dose-rate effects of p-channel metal oxide semiconductor field-effect transistors at various biasing conditions

The total-dose response and annealing effect of p-channel metal oxide semiconductor field-effect transistors （PMOSFETs） were investigated at various dose rates and biasing conditions.The results show that the shift of threshold voltage is more obvious when the dose rate is decreased.Under the various dose rates and biasing conditions,some have exhibited a time-dependent effect and others showed enhanced low-dose-rate sensitivity（ELDRS）.Finally,using the subthreshold-separating method,the threshold-voltage shift is separated into shifts due to interface states and oxidetrapped charges,and the underlying mechanisms of the observed effects are discussed.It has been indicated that the ELDRS effect results from the different quantities of the interface states generated at high and low dose rates.

From borophosphate to fluoroborophosphate:a rational design of fluorine-induced birefringence enhancement

The introduction of oxofluoride anion into anionic group assists to tune optical properties owing to the change of coordination,electronegativity,and according anionic framework.Here,we proposed a rational design of new compounds by fluorine-driven structure and optical property evolution.A new borophosphate Ba_(2)BP_(3)O_(11)with the monoclinic space group P2_(1/c) has been synthesized in the sealed system.Ba_(2)BP_(3)O_(11)exhibits a rare P-O-P bridge formation,which is the first example in alkaline-earth metal borophosphates.By further substituting[BO_(4)]^(3-)with[BO_(3)F]^(4-),the first alkaline-earth metal/lead fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)with the same space group were designed.Since the scissors effect of fluorine,in M_(2)BP_(2)O_(8)F(M=Ba and Pb),a BO_(3)F tetrahedron corner-sharing with three PO_(4)tetrahedra forms 1D chains along the b-axial direction,which are filled by MO_(n)(M=Ba/Pb,n=5,6,8)distorted polyhedra.The first principles calculation shows that the borophosphate Ba_(2)BP_(3)O_(11)has a birefringence about 0.013@1,064 nm,while the fluoroborophosphates M_(2)BP_(2)O_(8)F(M=Ba and Pb)have the values of 0.035 and 0.043@1,064 nm,respectively.Such an apparent enhancement in birefringence is derived from synergies of the oxyfluoride and cation.The introduction of fluorine-containing heteroanionic groups provides a feasible strategy to design novel promising optical materials.