A/A/O/O工艺在包钢焦化废水处理中的应用

焦化废水处理是焦化厂环境污染治理工作中的一个难题.包钢焦化厂在酚氰废水处理站改扩建工程中采用了国内先进的A/A/O/O工艺.该工艺不但能很好地去除废水中的酚、氰、CODcr等污染物,还能有效降解氨氮浓度,使之达到国家二级排放标准.     

热压烧结制备Li3/8Sr7/16Ta3/4Hf1/4O3钙钛矿型固体电解质

采用热压烧结制备了Li_3/8Sr_7/16Ta_3/4Hf_1/4O₃钙钛矿型固体电解质, 研究了不同烧结方式对样品性能的影响。通过X射线衍射仪表征材料的晶体结构, 扫描电子显微镜观察组织形貌, 交流阻抗仪测试电化学性能。结果表明:样品为立方KTaO₃相, 热压烧结成功合成了钙钛矿结构固体电解质, 相对于常压烧结, 热压烧结制备的样品孔隙更少, 晶粒之间结合更加紧密, 致密度高达94.0%, 离子电导率为4.33×10-4S·cm(T=298K).      

TiN/TiCN/Al2O3/TiN CVD多层涂层硬质合金的氧化行为

采用高温化学气相沉积(HT-CVD)和中温化学气相沉积(MT-CVD)相结合的复合化学气相沉积新技术在硬质合金基体WC-(W,Ti)C-(Ta,Nb)C-6%Co上分别沉积TiN/TiCN/TiN和TiN/TiCN/Al2O3/TiN涂层,制备TiN/TiCN/TiN和TiN/TiCN/Al2O3/TiN CVD多层涂...     

LiNi1/3Co1/3Mn1/3O2正极材料的合成与性能

采用共沉淀-高温固相法制备LiNi_1/3Mn_1/3Co_1/3O₂正极材料,利用XRD和SEM对所制试样的晶体结构和形貌进行表征,研究了烧结温度对材料电化学性能的影响.结果表明,焙烧温度为850 ℃制备的材料具有较好电化学性能,在25 ℃,电压范围为2.75~4.2 V,1 C充电6 C放电下首次放电比容量为124.2 mAh/g,50次循环后容量保持率为95.2 %.      

锂离子电池正极材料LiNi1/3Co1/3Mn1/3O2研究进展

介绍了比容量高、循环性能优异、成本较低的LiNil/3Co1/3Mnl/3O2正极材料近年来在合成技术及其掺杂改性、表面修饰等方面所取得的成果和进展,并对其未来的发展趋势进行了展望。     

Cu/Mo/Cu平面层状复合材料的研究进展

总结了Cu/Mo/Cu平面层状复合材料的特点和应用,通过平面层状结构设计,可以实现其在平面(x,y)方向更低的热膨胀系数和更高的热导率,其中热导率最高可达370W·m-1·K-1;介绍了其研究现状和制备方法,并通过对制备工艺的对比分析,指出热压复合和轧制复合是Cu/Mo/Cu层状复合材料生产工艺的发展趋势及方向.     

钒掺杂对LiNi1/3Co1/3Mn1/3O2正极材料电化学性能的影响

LiNi_1/3Co_1/3Mn_1/3O₂ (LNCM)因其高比容量等优点在动力电池领域受到广泛关注。然而,较差的循环性能和严重的安全问题限制了其应用前景。离子掺杂是提高材料电化学性能的有效方法之一。采用溶胶凝胶法,以NH₄VO₃为钒源,成功制备了钒掺杂LiNi_1/3-xCo_1/3Mn_1/3V_xO₂正极材料。结果表明:LiNi_1/3-0.02Co_1/3Mn_1/3V_0.02O₂ (LNCMV)电极材料表现出优秀的储锂性能(0.5 C时,80次循环后,放电比容量为169 mAh/g)。通过V⁵⁺替代LiNi_1/3Co_1/3Mn_1/3O₂正极...     

GB/T699和GB/T3077标准探讨

对GB/T 6 99和GB/T 30 77标准进行了分析和探讨 ,提出了新标准中存在的一些问题 ,并提出了一些建议。     

铌/钢和钽/钛/钢层状复合材料中铌层和钽层的氢化剥离回收

研究了氢化法剥离回收废旧铌/钢、钽/钛/钢层状复合材料中铌层、钽层。结果表明,氢化温度和氢化时间对复层剥离均有较大的影响。其中,铌/钢层状复合材料的最佳剥离条件为氢化温度800℃、氢化时间1.0 h,剥离得到的氢化铌块体中杂质元素Fe的含量为0.007 8%。钽/钛/钢层状复合材料最佳剥离条件为氢化温度600℃、氢化时间1.5 h,剥离得到的氢化钽块体中杂质元素Ti的含量为0.127%。     

谈B/S软件超越C/S软件的优势

B/S模式是一种以Web技术为基础的新型的MIS系统平台模式,把传统C/S模式中的服务器部分分解为一个数据服务器与一个或多个应用服务器(Web服务器),从而构成一个三层结构的客户服务器体系,B/S结构软件将全面取代C/S结构软件.     

Au/Ni/Al/Ti/AlxGa1-xN/GaN和Au/Pt/Al/Ti/AlxGa1-xN/GaN欧姆接触研究

研究并对比了Ti/Al/Ni/Au和Ti/Al/Pt/Au多层金属膜与未掺杂的Al0 .2 2 Ga0 .78N/GaN(i AlGaN/GaN)异质结构之间的欧姆接触性质。在退火温度低于 70 0℃时 ,两种接触样品上都不能得到欧姆接触。随着退火温度的升高 ,85 0℃快速退火后 ,在Ti/Al/Ni/Au接触上获得了 1.2 6×10 - 6 Ω·cm2 的比接触电阻率 ,在Ti/Al/Pt/Au接触上获得了 1.97× 10 - 5Ω·cm2 的比接触电阻率。研究结果表明 ,金属与半导体接触界面和Al0 .2 2 Ga0 .78N异质结构界面载流子沟道之间适当的势垒的存在对高质量欧姆接触的形成起重要作用 ,势垒的宽度取决于退火温度以及退火的具体进程。对Ti/Al/Ni/Au和Ti/Al/Pt/Au欧姆接触比接触电阻率的差异进行了解释。     

Effect of metal doping into Ce0.5Zr0.5O2 on catalytic activity of MnOx/Ce0.5–xZr0.5–xM0.2xOy/Al2O3 for benzene combustion

The research investigated the effect of doping two metals separately or together into Ce0.5Zr0.5O2 on the catalytic activity of MnOx/Ce0.5-xZr0.5-xM0.2xOy/Al2O3 （M=Y, Mn, Y and Mn） for catalytic combustion of benzene. The prepared catalysts were characterized by X-ray diffraction （XRD）, surface area analysis, oxygen storage capacity （OSC）, and H2-temperature programmed reduction （H2-TPR）. Catalytic test was performed on a conventional fixed bed flow reactor. The characterization results revealed that Y and Mn ions entered into the ceria-zirconia mixed oxides framework, which improved the textural properties and greatly promoted the MnOx dispersion on the support surface. The complete conversion temperature of benzene on MnOx/Ce0.4Zr0.4Y0.1Mn0.1Oy/Al2O3 was 563 K, and the selectivity of carbon dioxides was 99%. This catalyst could be applied in a wide range of GHSV and wide concentration condition, showing great potential for application.     

Superconducting Transition Temperature in YBa2Cu4O8/La2/3 Ca1/3 MnO3 / YBa2 Cu4O8 Heterostructure

YBa2Cu4O8/La2/3 Ca1/3 MnO3/YBa2Cu4O8 （ Y-124/LCMO/Y- 124） heterostructure was prepared by facing-target sputtering technique. The oscillatory superconducting transition temperature was observed when the thickness of LCMO d L is larger than critical thickness d L^CR. The metal-insulator transition temperature can only be detected at d L 〉 d L^CR. The dependence on the spacer layer in LCMO/Y-124 systems suggests strongly the interplay of ferromagnetic and superconducting couplings.     

Effect of Zn Doping on Transport Properties of La2/3 Sr1/3 Mn1 - x Znx O3 Films

La2/3 Sr1/3 Mn1-x ZnxO3films （x =0.05, 0.1,0.3, and 0.5） were prepared using magnetron sputtering method, and the effect of Zn doping on transport properties of the films was studied. An analysis of X-ray diffraction showed that the main phase of the bulk target was orthorhombic and the films had better epitaxial character. It was found that the films with x =0.05 and x =0.1 exhibited typical insulator-metal transition. No transition of the films with x≥0.3 was observed and the dominant transport was variable-range hopping due to observable secondary phase ZnO. These could be attributed to the Zn doping effect on manganites.     

锂过量对钙钛矿型Li3/8Sr7/16Ta3/4Hf1/4O3固体电解质性能的影响

固相烧结法合成钙钛矿型Li_3/8Sr_7/16Ta_3/4Hf_1/4O₃(LSTH) 固体电解质材料,制备过程中分别加入过量的碳酸锂,质量分数分别为(0~30 %).通过XRD、SEM、ICP-OES以及EIS测试,表征不同锂过量LSTH固体电解质材料成相、显微形貌以及室温电导率的影响.实验结果表明,配料时,过量一定质量百分数的碳酸锂,能够有效减少烧结过程中因锂挥发而生成的SrTa₂O₆杂相,提高样品密度和室温电导率.样品最佳锂过量质量百分数为20 %,20 %锂过量样品1 300 ℃烧结10 h为钙钛矿纯相,密度6.5 g/cm3,室温电导率达到3.12×10-4 S/cm.      

Antigenic drift between the haemagglutinin of the Hong Kong influenza strains A/Aichi/2/68 and A/Victoria/3/75

A DNA copy of the gene coding for the influenza A/Aichi/2/68 haemagglutinin protein was cloned in the plasmid pBR322 and the complete nucleotide sequence determined. Comparison of this primary structure and the deduced amino acid sequence with the haemagglutinin gene and protein of strains belonging to the same (H3) subtype and to different subtypes, of both human (H2) and avian (Hav1) origin, documents further at the molecular level the two independent modes of antigenic variation of the virus--drift and shift.     

Catalytic combustion of diesel soot over K2NiF4-type oxides La2-xKxCuO4

Nanostructure K2NiF4 type oxides La2-xKxCuO4 complex oxides were prepared using the Sol-Gel method, characterized by X-Ray Diffraction （XRD）, Fourier Transform Infrared （FT-IR）, and Scanning Electron Microscopy （SEM）. The catalytic activity for soot combustion was evaluated by the Temperature-Programmed Reaction （TPO） technique. The results demonstrated that the substitution quality of K^＋ for La^3＋ at the A-site would increase the catalytic activities of La2-xKxCuO4 for soot combustion greatly; the substitution quality affected the structure and catalytic activity obviously. The La1.8K0.2CuO4 complex oxides with tetrahedral structures had the best catalytic activity for soot combustion, and the ignition temperature of soot combustion was lowered from 490 to 320 ℃.