锂离子电池正极材料Li3V2-xNix(PO4)3的制备及其性能

采用溶胶-凝胶法,以Li2CO3、V2O5、NH4H2PO4、柠檬酸、Ni(OH)2·H2O为原料成功合成了正极材料Li3V2(PO4)3及其掺Ni化合物。Rietveld精修结果显示在Ni掺杂量不超过0.15时,样品均为纯相。X射线衍射(XRD)结果给出,随着镍掺杂量的增加,a轴和c轴及晶胞体积都有所下降。对样品Li3V2-xNix(PO4)3电导率的测试结果显示,Ni掺杂后样品的电子导电性均有所提高。室温下在0.1C和3C充放电条件下,镍掺杂Li3V1.95Ni0.05(PO4)3正极材料首次放电比容量分别达到177.2mAh/g和136.6mAh/g,在3C倍率下100次循环后容量保持率达到94.2%,这些性能都优于未掺杂样品和其他镍掺杂量的样品。     

Ti/Al/Ni/Au与n型GaN的欧姆接触研究

通过电流 电压 (I V)特性和传输线方法 (TLM )测量研究在n型GaN上淀积Ti/Al/Ni/Au电极形成欧姆接触的机制。Ni/Au作为Ti/Al的覆盖层起了阻止Ti ,Al,Au的互扩散及抗接触层氧化的作用。在 4 0 0℃到 90 0℃范围内 ,Ti/Al/Ni/Au与n型GaN的接触电阻随温度升高先略有上升 ,到 5 0 0℃以后单调下降。而表面形貌却在合金温度高于6 0 0℃以后随温度升高逐步变差。通过两步合金法得到了n GaN上Ti/Al/Ni/Au形成的接触电阻低达 9.6 5× 1 0 - 7Ωcm2 。最后还对两步合金法形成n GaN欧姆接触的机制进行了讨论。     

冷堆焊高碳Nb-Ti-V系钢质堆焊金属中的碳化物

研究了不同成分的冷堆焊高碳Nb-Ti-V系堆焊金属中碳化物的分布、形态,分析了碳化物在冷焊条件下的形成过程.Nb、Ti可以形成颗粒碳化物,但单独加入且含量较高时,碳化物尺寸过大,对基体固溶强化较弱,堆焊金属硬度过低;单独加入V时则形成了网状碳化物;适量Nb、Ti、V同时加入,获得了均匀分布的颗粒碳化物及强韧的基体,堆焊金属耐磨性优于D317的堆焊金属.     

喷气燃料加氢装置兼顾生产国V柴油的运行分析

介绍了中国石化塔河炼化0.3 Mt/a 喷气燃料加氢装置以常一线为原料,间歇生产满足GB 6537—2006的3号喷气燃料和满足国Ⅳ或国Ⅴ排放标准的柴油产品的生产经验。柴油产品全面升级后,通过简单的工艺调整,可以实现生产喷气燃料及生产满足国Ⅴ排放标准柴油两种加工方案的切换。生产3号喷气燃料,生产满足国Ⅳ排放标准柴油,生产满足国Ⅴ排放标准柴油这三种加工方案下,反应器入口温度依次相差约20℃。通过比较不同加工方案的差异性及催化剂的失活速率,提出今后喷气燃料加氢装置催化剂长周期运行的建议。     

City as Political Form: Four Archetypes of Urban Transformation

Pier Vittorio Aureli focuses on the category of archetype as an alternative to the idea of type. Four examples – the axial streets of Renaissance Rome, the 17th-century Parisian place, the 19th-century independent block in Berlin and the 20th-century Viennese superblock – are explored here to describe the emergence of modern urban forms that explicitly embody power relations.     

Continuous online monitoring of ionic dialysance allows modification of delivered hemodialysis treatment time

Considerable intrinsic intrapatient variability influences the actual delivery of Kt/V. The aim of this study is to examine the feasibility of using continuous online assessment of ionic dialysance measurements (Kt/V(ID)) to allow dialysis sessions to be altered on an individual basis. Ten well-established chronic hemodialysis (HD) patients without significant residual renal function were studied (mean age 65+/-4.3 [38-81] years, mean length of time on dialysis 66+/-18 [14-189] months). These patients had all been receiving thrice-weekly 4-hr dialysis using Integra dialysis monitors. Dialysis monitors were equipped with Diascan modules permitting measurement of Kt/V(ID). Predicted treatment time required to achieve a Kt/V(ID) > or = 1.1 (equivalent to a urea-based method of 1.2) was calculated from the delivered Kt/V(ID) at 60 and 120 min. Treatment time was reprogrammed at 2 hr (ensuring all planned ultrafiltration would be accommodated into the new modified session duration). Owing to practical issues, and to avoid excessively short dialysis times, these changes were censored at no more than+/-10% of the usual 240-min treatment time (210-265 min). Data were collected from a total of 50 dialysis sessions. Almost all sessions (47/50) required modification of the standard treatment time: 13/50 sessions were lengthened and 34/50 shortened (mean length of session 232.2+/-2.5 [210-265] min). A Kt/V(ID) of > or = 1.1 was achieved in 39/50 sessions. The difference in mean urea-based Kt/V poststudy (1.3+/-0.05 [1.1-1.6]) and mean achieved Kt/V(ID) (1.16+/-0.02 [0.7-1.37]) was significant (p = 0.002). The use of individualized variable dialysis treatment time using online ionic dialysance measurements of Kt/V(ID) appears both practicable and effective at ensuring consistently delivered adequate dialysis.     

Impact of RN genotype and ageing time on colour characteristics of the pork muscles longissimus dorsi and semimembranosus

The effect of RN genotype on pH decline, ultimate pH, pigment content, blooming and colour stability during 6 days of display at 5 °C was studied in two pig muscles, M. longissimus dorsi (LD) and M. semimembranosus (SM), and furthermore the effect of anaerobic storage time (2 days vs. 9 days of ageing) on the same parameters was examined. The postmortem pH decline was faster and the ultimate pH lower in LD and SM of the RN⁻ genotype compared with corresponding muscles from the rn⁺ genotype. Pork of the RN⁻ genotype was initially lighter and more red and yellow than pork of the rn⁺ genotype due to a higher degree of blooming, which might be explained by the faster pH decline and/or lower ultimate pH. The level of oxymyoglobin (MbO₂) was decisive for the redness of both muscles during display in air despite a higher presence of metmyoglobin (MetMb). Pork of the RN⁻ genotype was thus redder than that of the rn⁺ genotype throughout display in air despite higher oxidation to MetMb. Ageing for 9 days in chill improved the blooming potential in pork of both genotypes compared with 2 days of ageing, resulting in superior meat colour. However, only in pork from the RN⁻ genotype, the colour was not negatively affected by ageing time upon display in air.     

基于FAN7710V的CFL镇流器原理与设计

FAN7710V是利用飞兆的独特高压工艺和系统在封装中的概念研制的紧凑型荧光灯镇流器控制IC。FAN7710V控制内部高压应力并在310V的DC电压上为灯交付20W功率。本文介绍了基于TFAN7710V的CVL镇流器工作原理与设计。     

燃烧法V_2O_5-TiO_2催化3-甲基吡啶氧化性能的研究

研究了以燃烧法制备的V_2O_5-TiO_2催化剂用于3-甲基吡啶空气氧化制备烟酸的工艺过程。结果表明,该V_2O_5-TiO_2催化剂对3-甲基吡啶氧化制备烟酸的反应具有优异的催化性能。优化的反应条件为:温度280℃,3-甲基吡啶体积空速为0.2 h~(-1),n(空气):n(水):n(3-甲基吡啶)=79:40:1,氧化产物烟酸的产率达到97.4%,纯度达99.0%。