基于PLC控制的插头E极芯针自动压机设计

针对插头接地极进行芯针组装工作设计了一款自动压机,采用了"分体制造+压力组装"的组装工艺。着重对四步循环工艺流程、机械结构设计、PLC选型和程序设计进行了阐述。经企业实际应用,该设备运行稳定、使用可靠,实现了生产过程的自动化。

康宁644电解质分析仪电极的修复

康宁644电解质分析仪,有钾、钠、氯和参比四个电极,电极正常寿命为一年,在工作中我们发现,当电极使用至一年左右时,仪器斜率很难通过,影响正常工作,若更换一套新电极则价格昂贵。为此,我们用下述方法进行电极处理,效果满意,可使电极延长寿命2倍以上,现介绍如下。

铅酸蓄电池损坏机理的浅探

本文通过对铅酸蓄电池正极极芯铅柱氧化，电瓶极板(极柱)及局部反极等方面的论述，说明造成电瓶损坏甚至不可修复的主要原因，并从化学原理角度分析，提出改进意见。

热复合式叠片机在锂离子电池中的应用研究

电芯制造是锂离子电池生产的核心环节,电芯质量的高低对电池质量的优劣有着决定性影响,卷绕和叠片是目前锂离子电池极芯制造的两种主要工艺方式。随着新能源汽车的普及以及锂离子电池在其他行业需求日益增长,对电池的质量和性能要求越来越高,现有极芯制造设备已不能满足高质量锂离子电池生产的需求。通过对现有锂离子电池极芯制造技术的剖析,在现有叠片技术的基础上提出了一种集正负极裁切、热复合、叠片、热压与包胶等工序于一体的锂离子电池极芯制造设备——热复合式叠片机,实现极芯全片式叠片,并结合现有技术的缺陷与不足对热复合叠片机运用在锂离子电池极芯制造中的特点和优势进行阐述,可以看出,热复合式叠片机在锂离子电池乃至未来可能产业化的固态、半固态锂电池生产制造中具有十分重要的作用。

计算机入门 微机在家庭中的应用

目前,一般家庭购置的微机大致具有以下的功能:1.学习既不要书本,也不要纸笔,只要插上电源,启动相应的学习软件,通过微机就可以对各种知识进行学习的测试,有些软件甚至可以分析试卷,指出不足,并进行针对性的辅导.

A 5.4mW and 6.1% efficiency fixed-tuned 214GHz frequency doubler with Schottky barrier diodes

A Y-band frequency doubler is analyzed and designed with GaAs planar Schottky diode, which is flip-chip solded into a 50 μm thick quartz substrate. Diode embedding impedance is found by full- wave analysis with lumped port to model the nonlinear junction for impedance matching without the need of diode equivalent circuit model. All the matching circuit is designed ＂on-chip＂ and the mul- tiplier is self-biasing. To the doubler, a conversion efficiency of 6.1% and output power of 5.4mW are measured at 214GHz with input power of 88mW, and the typical measured efficiency is 4.5% in 200 - 225 GHz.

Development of Spaceborne Antenna for Circularly Polarized SAR Using Kevlar Honeycomb Core

This paper presents the development of circularly polarized microstrip antenna using Kevlar honeycomb core as the substrates for application of CP-SAR （circularly polarized synthetic aperture radar） which signal propagation is not affected by Faraday rotation effect in the ionosphere, as compared to linearly polarized systems especially at the L-band. The reason why Kevlar honeycomb core is used is because it is suitable for space environment in terms of lightweight and resistant to heat and shock. Measurements of the fabricated antenna were performed to confirm the simulation results. The results show good characteristics of the antennas except the axial ratio. The reason of insufficient axial ratio is assumed as fabrication error of the radiator and microstrip line.

Factors controlling the nitrate in the DT-401 ice core in eastern Antarctica

Nitrate,an oxidized product of NO x preserved in the polar ice cores,has often been used to estimate past changes of the atmospheric nitrogen cycle.A 102.65 m ice core drilled at DT-401(79°01'S,77°00'E) in 1999 provides an opportunity to investigate the possible influencing factors for the nitrate budget in the eastern Antarctica.We studied the relationship between the δ18O(representing the temperature),accumulation rate,volcanic deposition and the astronomical factors(such as the solar activities,supernovae,etc.),and the nitrate variation along the whole duration(2680-year) of the ice core.Prominent impacts of the accumulation rate acting on the nitrate flux rather than the concentration were detected.However,no significant correlation was found between the δ18O and the nitrate deposition characteristics(concentration and the flux variations).Volcanic deposition can significantly affect the deposition of nitrate with a decreasing trend accompanied by the nss-SO42(volcanic signal) peak values.Impacts of the solar activities on the nitrate deposition can be detected at this site,and three prominent periodicities(16.6,24.0 and 102.0 yr) were found for the nitrate concentration variations.Six climatic events(Dalton Minimum,Maunder Minimum,Sporer Minimum,Wolf Minimum,Oort Minimum and Medieval Maximum) during the past 1150 years were observed with lower nitrate values for the foregoing five events and higher value for the last one.

Structure of the internal isochronous layers at Dome A,East Antarctica

Dome A (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequisite for selecting sites for deep ice core drilling that can be used for studying the paleoclimatic record. In 2004/2005, during the 21st Chinese National Antarctic Research Expedition (CHINARE 21), a 200-km long, continuous radar profile was obtained across Dome A. The internal layers along the profile were derived from the stratigraphy detected by the radar. The morphology of the isochronous layers shows that: (1) The internal layers in the shallow ice sheet (0-500 m) are generally flat, with no more than 50 m of layer intervals, and have typical synclines and anticlines in some localized regions. (2) At 500-2000 m below the surface of the ice sheet, the layers appear as 'bright layers', and the width of the layer intervals expands to 50-100 m. (3) When the basal topographic wavelengths are approximate to the thickness of the ice (3 km), the traced internal layers, with localized bumps or concave folds, are asymptotic parallel to the subglacial topography. For the longer topographic wavelengths (~20 km) wider than the thickness of the ice, the layers do not rise and fall with the basal topography. The internal layers surrounding some mountain peaks representing the most extreme variation in the terrain are sharply disturbed by the subglacial topography. (4) Layer discontinuity and fracture were detected in the basal ice sheet. Finally, by combining this new information with that derived from existing data regarding ice thickness, we were able to select three potential sites for reconstructing the age-depth relationship of the ice core.

A compact neural recording interface based on silicon microelectrode

A prototype of hybrid neural recording interface has been developed for extracellular neural recording. It consists of a silicon-based plane microelectrode array and a CMOS low noise neural amplifier chip. The neural amplifier chip is designed and implemented in 0.18 μm N-well CMOS 1P6M technology. The area of the neural preamplifier is only 0.042 mm2 with a gain of 48.3 dB. The input equivalent noise is 4.73 btVrms within pass bands of 4 kHz. To avoid cable tethering for high dense mul- tichannel neural recording interface and make it compact, flip-chip bonding is used to integrate the preamplifier chip and the microelectrode together. The hybrid device measures 3 mm×5.5 mm×330μm, which is convenient for implant or in-vivo neu- ral recording. The hybrid device was testified in in-vivo experiment. Neural signals were recorded from hippocampus region of anesthetized Sprague Dawley rats successfully.

A 2680-year record of sea ice extent in the Ross Sea and the associated atmospheric circulation derived from the DT401 East Antarctic ice core

Long time series of Antarctic sea ice extent （SIE） are important for climate research and model forecasting. A historic ice extent in the Ross Sea in early austral winter was rebuilt through sea salt ions in the DT401 ice core in interior East Antarctica. El Nino-Southern Oscillation （ENSO） had a significant influence on the sea salt deposition in DT401 through its influence on the Ross Sea SIE and the transport of sea salt inland. Spectral analysis also supported the influence of ENSO with a significant 2-6 a periodicity band. In addition, statistically significant decadal （10 a） and pentadecadal （50-70 a） periodicities suggested the existence of a teleconnection from the Pacific decadal oscillation （PDO）, which originated from sea surface temperature anomalies in the tropical Pacific Ocean. The first eigenvector of the empirical orthogonal function analysis （EOF1） showed lower values during the Medieval Warm Period （MWP）, while higher values were found in the Little Ice Age （LIA）. A higher frequency of ENSO events were found in the cold climatic stage, The post 1800 AD period was occupied by significant fluctuations of the EOF1, and PDO may be one of the influencing factors. The EOF1 values showed moderate fluctuations from 680 BC to 1000 AD, showing that the climate was relatively stable in this period.

Characteristics of on-chip dipole antenna using diamond for intra-chip wireless interconnect

In this paper,a 2-mm long on-chip dipole antenna pair on silicon substrate is simulated to investigate the transmission characteristics.A novel technique is proposed by employing a 0.35-mm thick diamond layer between silicon substrate and heat sink to improve antenna performance.The simulated transmission gain of this antenna pair with 1 mm separation on a 10-Ω cm silicon substrate increases by 9 dB at 20 GHz.A modified plane wave model involving diamond layer is also presented to explain gain improvement.Effects of dielectric variety,diamond thickness,substrate resistivity and antenna pair separation on transmission gain have been studied.The results indicate that thinner diamond layer along with high resistivity substrate is preferred.Our method makes integrated dipole antennas well suitable for intra-chip wireless interconnection which is known as a future solution to replace critical wiring interconnection.