Performance of LiNi1/3Co1/3Mn1/3O2 prepared from spent lithium-ion batteries by a carbonate co-precipitation method

Spherical LiNi_1/3Co_1/3Mn_1/3O₂ cathode particles were resynthesized by a carbonate co-precipitation method using spent lithium-ion batteries (LIBs) as a raw material. The physical characteristics of the Ni_1/3Co_1/3Mn_1/3CO₃ precursor, the (Ni_1/3Co_1/3Mn_1/3)₃O₄ intermediate, and the regenerated LiNi_1/3Co_1/3Mn_1/3O₂ cathode material were investigated by laser particle-size analysis, scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS), thermogravimetry–differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), inductively coupled plasma–atomic emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the regenerated LiNi_1/3Co_1/3Mn_1/3O₂ was studied by continuous charge–discharge cycling and cyclic voltammetry. The results indicate that the regenerated Ni_1/3Co_1/3Mn_1/3CO₃ precursor comprises uniform spherical particles with a narrow particle-size distribution. The regenerated LiNi_1/3Co_1/3Mn_1/3O₂ comprises spherical particles similar to those of the Ni_1/3Co_1/3Mn_1/3CO₃ precursor, but with a narrower particle-size distribution. Moreover, it has a well-ordered layered structure and a low degree of cation mixing. The regenerated LiNi_1/3Co_1/3Mn_1/3O₂ shows an initial discharge capacity of 163.5 mA h g^?1 at 0.1 C, between 2.7 and 4.3 V; the discharge capacity at 1 C is 135.1 mA h g^?1, and the capacity retention ratio is 94.1% after 50 cycles. Even at the high rate of 5 C, LiNi_1/3Co_1/3Mn_1/3O₂ delivers the high capacity of 112.6 mA h g^?1. These results demonstrate that the electrochemical performance of the regenerated LiNi_1/3Co_1/3Mn_1/3O₂ is comparable to that of a cathode synthesized from fresh materials by carbonate co-precipitation.     

Mechanism of smoke suppression by melamine in rigid polyurethane foam

The smoke suppression of rigid polyurethane foam (RPUF) modified by melamine was investigated based on three sections: the condensed phase, the carbon layer, and the gas phase. In the condensed phase, the results of thermogravimetry, X‐ray photoelectron spectroscopy (XPS) N1S spectrum, and Fourier transform infrared spectroscopy indicated that melamine could suppress the degradation of RPUF by reacting with the aromatic hydrocarbons. It also reduced the smoke generation because the volatilizable aromatic hydrocarbons were the principal smoke precursors in a fire. In the carbon layer, the decrease from 38.50% to 24.76% of the inner layer oxygen content identified by XPS full‐spectrum and C1S spectrum indicated that melamine could prevent oxygen from transferring into the inner foam by the formation of an enhanced surface carbon layer, and the enhanced carbon layer could also block the release of smoke precursors. In the gas phase, the content of total aromatic hydrocarbons declined to 59.12% according to pyrolysis gaseous chromatography mass spectroscopy and indicated that melamine could reduce the smoke precursors. The results of smoke density chamber and cone calorimeter tests revealed that the addition of the melamine could decrease the smoke density of burning RPUF. Copyright © 2014 John Wiley & Sons, Ltd.     

On keys' meanings and modes: the impact of different key solutions on children's efficiency using a mobile phone

The present study investigates the impact of different key solutions of mobile phones on users' effectiveness and efficiency using the devices. In the first experiment, 36 children (9 - 14 years) and in the second experiment 45 young adults (19 - 33 years) completed four common phone tasks twice consecutively on three simulated phones that had identical menus, but different key solutions. An approach was undertaken to quantify the complexity of keys in three models, incorporating different factors contributing to the keys' complexity (number of key options, number of modes and number of modes with a semantically dissimilar meaning), in order to predict users' performance decrements. As a further main factor, the degree of the users' locus of control (LOC) was measured and interactions with performance outcomes were studied. As dependent measures, the number of inefficient keystrokes, the number of tasks solved and the processing time were determined. Results showed a significant effect of control key solutions on users' efficiency and effectiveness for both children and young adults. Moreover, children's LOC values significantly interacted with performance: children with low LOC values showed the lowest performance and no learnability, especially when using keys with a high complexity. From the three factors contributing to the complexity of keys, keys exerting different functions with semantically inconsistent meanings had the worst effect on performance. It is concluded that in mobile user interface design keys with semantically inconsistent meanings should be generally avoided.     

A primary study of the acoustics of Chinese traditional theatrical buildings

The traditional performing arts and theatrical buildings in China can be traced back to a long history and were well developed during Song and Yuan Dynasties, 11th-14th centuries. Pavilion stage, opened on three sides and thrusting into the audience area, was unique and the most popular form in the open-air theatres, the courtyard theatres, and the indoor theatres up to the present day. As the traditional Chinese opera is performed in an abstract way, no stage settings are required and used. Therefore, the pavilion stage including the flat or domed ceiling and the back wall is virtually functioned as a reflective shell, which increases the early reflections and also intensifies the sound in the audience area. Meanwhile, it provides sufficient self-support to the performers. Acoustical parameters including reverberation time RT, early decay time EDT, acoustic ratio C50, strength index (loudness) G, and stage support factor ST1 were measured and reported on several traditional theatrical buildings.     

Handover and Uplink Power Control Performance in the 3.84 Mcps TDD mode of UTRA Network

In this article we consider the performance of the 3.84 Mcpstime-division duplex (TDD) mode of UTRA (Universal TerrestrialRadio Access) network. We emphasize two of the radio resourcemanagement algorithms, handover and uplink power control, whoserole in the overall system performance is studied extensively.First, a handover algorithm used in WCDMA (Wideband Code DivisionMultiple Access) standard is considered in a TDD-mode operation.This gives rise to a careful setting of different handoverparameters, and the evaluation of the effects to the systemperformance. Secondly, the specified uplink power controlalgorithm is considered. Since it is based on several user-mademeasurements which may involve both random and systematic errors acareful study about the suitability of the power control scheme iscarried out.     

低流度油藏分类及开发特征研究

低流度油藏指流度低于30×10-3μm2/mPa.s的油藏。根据流度大小以及油藏在开发生产中表现出的特征,可将低流度油藏分为一般低流度油藏、特低流度油藏和超低流度油藏。对大港低流度油藏的研究表明,由于低流度油藏地质情况复杂,地层认识不清,因而开发特征复杂,表现为采油速度低,采出程度和采收率低;注水效果差,油藏井距不适应;油井见水后含水迅速上升,产量则急剧下降。     

柯克亚油气田混合来源天然气的地球化学特征

柯克亚油气田是我国开发比较早的一个油气田,但由于受混源和其他因素的影响,对气源的认识众说纷纭。通过对天然气的地球化学特征的分析,并参照国内外关于甲烷、乙烷、丙烷碳同位素关系方面的资料,提出了如下看法:柯克亚天然气碳同位素相对较重,与塔里木盆地下古生界海相天然气的碳同位素组成区别较大;根据天然气40Ar/36Ar组成,柯克亚油气田的气源不是单一来源;柯克亚油气田绝大多数天然气的甲烷和乙烷碳同位素值关系符合Faber推断的 型有机质方程直线关系,说明有机质属于较好的有机质类型,或者是由原油裂解形成的天然气;除了K2井和K18井天然气成熟度较低以外,绝大多数天然气的成熟度大约在1.8%～2.2%之间,属于高过成熟气,但也混有一些成熟度在0.9%～1.2%的源岩形成的天然气;推测天然气主要来源于石炭系―二叠系源岩,而混有成熟度低的源岩形成的天然气则有可能来自侏罗系源岩。     

PX型高效旋风分离器的研究开发

根据对PV型旋风分离器气固流动特性的深入研究,分析了几处影响细粉分离的薄弱环节,并针对性地提出了进气口倾斜、排气管切口及排尘口加防返混锥等结构改进措施.在φ300mm实验室模型试验台上,通过大量对比试验,开发出了一种比现有PV型性能更优良的新一代高效旋风分离器-PX型旋风分离器.实验室对比试验结果表明,相同条件下,PX型比PV型效率提高0.2～1.1个百分点,压力降降低10%～15%.     

铝钛共渗钢的研制与工业应用

介绍了开发的铝钛共渗工艺及其特点,该工艺可根据需要调整渗剂配方,实现渗钛或铝钛共渗.研究了一种封闭剂,重点解决了渗剂高温氧化烧结问题,使渗层质量优良、性能稳定.描述了铝钛共渗层的特征和焊接性能及耐腐蚀效果.在中国石化扬子石油化工股份有限公司炼油厂的应用表明,铝钛共渗钢具有良好的抗低温H2S腐蚀的能力,并具有优良的耐冲刷、耐磨蚀性能.     

湛江1.20 Mt/a加氢裂化装置的设计及运行

对湛江东兴石油企业有限公司1.20 Mt/a加氢裂化装置的工程设计及工业运转进行了总结,简要介绍了工艺及工程技术特点、装置的工业运转结果等,对装置的运转情况进行了分析.分析结果说明,在中等压力下,生产优质柴油和较低BMCI值尾油的工艺技术和工程设计是成功的.