Monodisperse and 1D Cross-Linked Multi-branched Cu @ Ni Core–Shell Particles Synthesized by Chemical Reduction

We report on a two-step wet chemical route for producing Cu@Ni core–shell particles with multiple needle-like branches on the surface. Using the usual synthesis process, urchin-like Ni shells were formed on the surface of spherical Cu cores and monodisperse particles were obtained. Under the direction of a static magnetic field, one-dimensional, well-aligned Cu@Ni particles were assembled through cross-linking the branched Ni shells. The monodisperse Cu@Ni particles show stable and uniform field electron emission, having a low turn-on field of 3.3 V/μm and a large current density of 1 mA/cm² under an applied field of about 5.33 V/μm.     

一种应急管理信息系统在海油企业中的应用

本文主要介绍一套适合海油企业实际业务应用的应急管理信息系统,系统通过模块化、组件化模式实现灵活应用配置,并可根据用户实际应用需求进行模块组合、拆解,为不同领域的企业和厂区搭建适用的定制化应用系统,满足企业日常安全应急管理需求,为应急指挥工作提供辅助决策支持。     

LS-DSP中串行分布式数字滤波器的功耗优化设计

采用一种优化阶符的二进制数据表示方法,达到了减小LS-DSP内串行分布式计算滤波器的动态功耗的目的.实验结果表明,该方法可有效减小LS-DSP内串行分布式计算滤波器10%的动态功耗.     

Insight into the Solid Electrolyte Interphase Formation in Bis(fluorosulfonyl)Imide Based Ionic Liquid Electrolytes

The formation of the solid electrolyte interphase (SEI) in an ionic liquid electrolyte of 0.5 m lithium bis(fluorosulfonyl)imide (LiFSI) in 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide at high cell voltages (1.7–1.9 V) is investigated in ordered mesoporous carbon (OMC) based Li metal cells using an operando small-angle neutron scattering (SANS) technique coupled with electrochemical impedance spectroscopy and ex situ X-ray photoelectron spectroscopy (XPS). It is demonstrated that discharging the OMC Li metal cells to ≈2 V and holding the cell voltage constant induces a rapid current increase with time, confirming extensive reduction and SEI formation. XPS analysis reveals that LiF is formed at open cell voltage (OCV), which is attributed to the carbenes generated at the lithium negative electrode because of its reaction with EMIm cation diffusing to and initiating the reaction with FSI⁻ anions at the carbon positive electrode. It is confirmed that the chemical reaction at OCV and electrochemical reduction at high cell voltage of the FSI⁻ anion plays a protective role against EMIm cation co-intercalation into the carbon positive electrode during the initial discharge. Operando SANS studies also suggest that slight differences occur in the surface composition and reaction mechanism as a function of cell voltage.     

Photothermal Modulation of Depression-Related Ion Channel Function through Conjugated Polymer Nanoparticles

Considering recent breakthroughs in the field of optogenetics, a powerful tool is established in the present study to modulate the activities of target neurons through the application of light-based methods. Near-infrared (NIR) light enables the penetration of deep-tissue. As a result, it can be used to modulate the functions of proteins/cells. Herein, it is aimed to develop a NIR light-sensitive drug delivery system to spatially and temporally control the activation of the loaded drug at the stimulation sites through its release from a nanoparticle sensitive to NIR. Owing to their excellent photothermal effect under NIR irradiation, the nanoparticles are found to penetrate the blood-brain barrier effectively, ultimately reaching neurons. Furthermore, by loading fasudil, a selective activator of the Kv7.4 potassium channel, into the precisely designed and synthesized NIR light-sensitive nanoparticles, the firing frequency of dopaminergic neurons in the ventral tegmental area is found to be remarkably reduced upon NIR light irradiation. Such findings shed light on a new concept that can be used for developing more selective drug therapies for the treatment of diseases, such as major depression.     

Direct View on the Origin of High Li+ Transfer Impedance in All-Solid-State Battery

Large interfacial resistance plays a dominant role in the performance of all-solid-state lithium-ion batteries. However, the mechanism of interfacial resistance has been under debate. Here, the Li⁺ transport at the interfacial region is investigated to reveal the origin of the high Li⁺ transfer impedance in a LiCoO₂(LCO)/LiPON/Pt all-solid-state battery. Both an unexpected nanocrystalline layer and a structurally disordered transition layer are discovered to be inherent to the LCO/LiPON interface. Under electrochemical conditions, the nanocrystalline layer with insufficient electrochemical stability leads to the introduction of voids during electrochemical cycles, which is the origin of the high Li⁺ transfer impedance at solid electrolyte-electrode interfaces. In addition, at relatively low temperatures, the oxygen vacancies migration in the transition layer results in the formation of Co₃O₄ nanocrystalline layer with nanovoids, which contributes to the high Li⁺ transfer impedance. This work sheds light on the mechanism for the high interfacial resistance and promotes overcoming the interfacial issues in all-solid-state batteries.     

Finite-Sized Atom Reconstruction Enhanced High-Frequency Multi-Domain Magnetic Response

The technological advances in wearable electronics and military stealth have spawned extensive research into electromagnetic wave absorbents. Despite the rapid progress in the geometrical modulation of magnetic absorbents, the engineering strategy of microwave-responsive magnetic domains is underdeveloped and the response dynamics remain unclear. Herein, a surface finite-sized atom reconstruction procedure is proposed to accurately modulate the local magnetic topological domains, dramatically enhancing the magnetic loss capacity. Due to the selectivity of atom reconstruction, vortex and stripe domains are controllably hybridized around the porous surface to broaden the interactive domain region, significantly intensifying energy absorption of the microwave field. Meanwhile, the amorphous/crystalline interfaces around atom reconstruction regions can induce interfacial polarization, enabling the optimization of dielectric loss capacity. Therefore, a satisfactory magnetic–dielectric synergy is realized to demonstrate the strong absorption intensity of −31.2 dB and the broad absorption bandwidth of 5.9 GHz. Furthermore, the surface-based magnetic domain transformation and microwave energy attenuation mechanisms are thoroughly revealed to break the black box of structure–function through electron holography and micromagnetic simulation. These achievements demonstrate a promising solution to improve high-frequency magnetic properties and provide a feasible route to interpret the structure-relevant magnetic loss capacity.     

976 nm高效率半导体激光器

976 nm高效率半导体激光器是这几年研究的热点,在固体激光器泵浦领域有广阔的应用。通过优化半导体激光器材料外延结构中包覆层和波导层的铝组分,降低了工作电压;通过采用微通道水冷系统,并进行优化降低了热阻,从而提高了室温下的电光转换效率。25℃室温连续测试条件下,1 cm的线阵列(巴条),2 mm腔长,50%填充因子,在110 A下,出光功率为114.2 W,电压为1.46 V,电光转换效率为71%。15条微通道封装成的垂直叠阵,进行光束整形后,获得了室温976 nm连续输出功率1 500 W,电光转换效率大于70%。     

移动通信业务安全综述

本文通过分析移动通信业务所面临的各类安全威胁,提出了移动通信业务安全架构,并对业务安全总体架构、业务应用安全各层实现、手机终端安全、用户卡安全等技术进行了具体的介绍.