钛酸铋钠Bi0．5Na0．5TiO3（BNT）的制备工艺

结合钛酸铋钠Bi0．5Na0．5TiO3（BNT）的性质,介绍了钛酸铋钠Bi0．5Na0．5TiO3（BNT）的制备工艺。     

掺杂和烧结对（SrPb）TiO3基陶瓷复合热敏特性影响的研究

采用正交实验法,研究了Ｙ含量、ＳｉＯ２含量、烧结温度及保温时间对（ＳｒＰｂ）ＴｉＯ３基陶瓷复合热敏特性的影响。实验结果表明：烧结温度是影响最低电阻率的关键因素,Ｙ含量对材料的正、负温度系数影响最大,ＳｉＯ２在一定量范围内对促进材料半导化是有利的。     

（R，R）-2，8-二氮杂双环[4．3．0]壬烷的合成

（R,R）-2,8-二氮杂双环[4．3．0]壬烷是莫西沙星合成过程中的一个副产物,对莫西沙星成品质量有较大影响。本文以8-苄基-2,8-二氮杂双环[4．3．0]壬烷为起始原料,经L-（＋）-酒石酸拆分,Pd／C催化加氢脱苄基,纯化制得含量〉99．5％的（R,R）-2,8-二氮杂双环[4．3．0]壬烷,总收率66．5％,并优化了合成工艺。     

5－（3，5－二溴－2－吡啶基）－1－（2－羟基－5－磺苯基）－3－（2－羟基苯基）甲的合成及其与铜显色反应的研究

介绍了显色剂５－（３，５－二溴－２－吡啶基）－１－（２－羟基－５－磺苯基）－３－（２－羟基苯基）甲（ＢＰＨＰＳ）的合成。详细研究了试剂与铜的显色反应，其灵敏度较高，摩尔吸光系数ε为２．４６×１０４。采用掩蔽方法，能显著提高体系的选择性。用拟定的方法测定了铜矿中的铜，结果令人满意。     

掺BaTiO3对（1-x）NBT—xBaTiO3系陶瓷材料的铁电牲能的影响

采用RadiantPrecisionWorkstation铁电测试系统测试样品的铁电性能,分析BaTiO3的掺人对（1-x）NBT—xBaTiO3系陶瓷材料的铁电性能的影响。实验结果表明：Ba2＋的掺入可有效地降低NBT基陶瓷的剩余极化强度和矫顽场,在准同型相界组成点,矫顽场达到最小值。     

ZnO-B2O3-SiO2玻璃对Ca[（Li1／3Nb2／3）0.95Zr0.15]O3＋δ微波介电性能的影响陶瓷

研究了ZnO-B2O3-SiO2（ZBS）玻璃对陶瓷的烧结性能及微波介电特性的影响。研究表明ZBS的掺入能有效降低Ca[（Li1／3Nb2／3）0.95Zr0.15]O3＋δ陶瓷体系的烧结温度150-200℃,谐振频率温度系数随ZBS掺入量增加及烧结温度的提高,由负值向正值方向移动。在1000℃,掺入质量分数7wt％的ZBN,陶瓷微波介电性能最佳：εr=31．1,Qf=9550GHz,Tf=-8．9ppm／℃,在960℃烧结4小时,可获得介电性能为：εf=28．6,Qf=641OGHz,Tf=-9．8ppm／℃陶瓷样品。     

新试剂5－（2′－羟基－3′，5′－二硝基苯偶氮）罗丹宁的合成及与钯（Ⅱ）显色反应的研究

报道新试剂５－（２′－羟基－３′，５′－二硝基苯偶氮）罗丹宁的合成及其与钯（Ⅱ）的显色反应。方法用于测定催化剂中钯的含量，结果较满意。     

2-（4’-羟基苯氧基）-3-氯-5-三氟甲基吡啶的合成

以对苯二酚与2，3-二氯-5-三氟甲基吡啶单醚化合成精吡氟氯禾灵的重要中间体2-（4’-羟基苯氧基）-3-氯-5-三氟甲基吡啶。探讨并得到了反应的最佳工艺条件：K2CO3为缚酸剂，二甲基亚砜和甲苯为溶剂，n（2，3-二氯-5-三氟甲基吡啶）：n（对苯二酚）：n（K2CO3）=1：2：1．08，不需要脱水。在回流条件下加入2，3-二氯-5-三氟甲基吡啶并反应5h。在此条件下，2，3-二氯-5-三氟甲基吡啶的转化率100％，产品的选择性大于98％。     

Al2（SO4）3对粘胶纤维截面形态和强伸性能影响的试验研究

介绍了Al2（SO4）3在粘胶纤维纺丝凝固浴中的作用,采用不同Al2（SO4）3含量的凝固浴进行纺丝试验,就Al2（SO4）3,对成形丝条的剩余酯化度、截面形态、强伸指标的影响进行了分析。试验结果表明,采用Al2（SO4）3,凝固浴以半连续纺丝机纺制的粘胶长丝,其截面具有皮芯结构、皮层薄、形状异形度高,而丝条强伸指标低于ZnSO4凝固浴纺制的丝条。     

低温烧结(Zn0.65Mg0.35)TiO3-CaTiO3介电陶瓷的研究

本文对(Zn0.65Mg0.35)TiO3-CaTiO3(ZMT-CT)系统的微观结构和介电性能进行了研究.研究结果表明,通过添加一定量H3BO3-ZnO-BaCO3(BZB)玻璃能够促进晶粒生长,有效降低烧结温度.同时,调节(Zn0.65Mg0.35)TiO3和CaTiO3比例可以获得温度系数在零附近的瓷料.当加入6.5wt%BZB时瓷料可以在900℃烧结,ε=21～22,αε＜±30 ppm/℃,tanδ=1.3×10-4(1 MHz),是制备LTCC(低温共烧陶瓷电容器)的优秀候选材料,具有很好的应用前景.     

复合烧结助剂对Ca_(0.3)(Li_(0.5)Sm_(0.5))_(0.7)TiO_3微波介质陶瓷低温烧结与性能研究

研究了以Ca_(0.3)(Li_(0.5)Sm_(0.5))_(0.7)TiO_3(CLST-0.7)为基料,复合添加10 wt%CaO-B_2O_3-SiO_2(CBS)、4 wt%Li_2O-B_2O_3-SiO_2-CaO-Al_2O_3(LBSCA)和0～2 wt%CuO氧化物为烧结助剂的微波介质陶瓷的低温烧结行为及微波介电特性.结果表明:随着CuO添加量的增加,陶瓷体积密度、介电常数ε_r、无载品质因数与谐振频率乘积Qf值,都呈先增加后降低,频率温度系数τ_f呈降低的趋势.添加10 wt%CBS、4.0 wt% LBSCA和1.0 wt%CuO的CLST-0.7微波介质陶瓷,在900 ℃烧结5 h具有较佳的微波介电性能:ε_r ＝ 67.31,Qf ＝ 2197 GHz,τ_f＝40.28 ppm/℃.     

(Bi_(1/2)Na_(1/2))TiO_3BaTiO_3系无铅压电陶瓷工艺的研究

详细探讨了在制备(Bi1/2Na1/2)TiO3 BaTiO3(abbr.BNBT)系无铅压电陶瓷的过程中,合成条件Ty和烧结温度Ts对材料压电介电性能的影响,确定了较好的制备BNBT系压电陶瓷的工艺条件,并且系统地研究了(1-x)·(Bi1/2Na1/2)TiO3 xBaTiO3(x=0 02、0 04、0 06、0 08、0 10)的性能。XRD结构分析发现系统的相界在x=0 06,此时d33等压电介电性能参数达到最佳值。     

Bi_(1/2)Na_(1/2)TiO_3-BaTiO_3系无铅压电陶瓷制备工艺的优化及其结构分析

借助正交试验设计,通过对无铅压电陶瓷压电、介电性能的测试,研究了BaTiO3含量、预烧温度、烧结温度及保温时间对(1-x)(B i1/2Na1/2)TiO3xBaTiO3(简写为BNBT 100x)陶瓷性能的影响。研究结果表明制备BNBT系陶瓷的最优化工艺条件为:BaTiO3摩尔分数x=0.06、预烧温度850℃、烧结温度1 130℃、保温时间2 h。通过XRD分析了BNBT系压电陶瓷的晶体结构类型、晶胞参数及晶格畸变随着BaTiO3摩尔分数的变化,确定了该体系的三方四方的准同型相界在x=0.06~0.08之间。     

(Bi1/2Na1/2)TiO3-BaTiO3系无铅压电陶瓷结构与性能的研究

采用XRD,SEM,HRTEM等分析技术对(1-x)(Bi1/2Na1/2)TiO3-xBaTiO3(简称为BNBT)(x为0.04,0.06,0.08,0.10)进行了结构与性能的研究,并主要分析了x为0.06,即0.94(Bi1/2Na1/2)TiO3-0.06BaTiO3(简称为BNBT6)在不同烧结温度下的结构形态及其对性能的影响.结果表明:(1-x)(Bi1/2Na1/2)TiO3-xBaTiO3系统具有很窄的烧结范围.另外,加入过量的Ba2+,能起到阻碍晶粒长大的作用.     

The Effect of Nickel on the Conversion of Amorphous Iron(III) Hydroxide into more Crystalline Iron Oxides in Alkaline Media

The effect of nickel (Ni) on the transformation of amorphous iron(III) hydroxide into more crystalline iron oxides has been followed using X-ray powder diffraction and chemical analysis. One aim of this study was to determine the fate of Ni that had been co-precipitated with amorphous iron(III) hydroxide as the amorphous phase recrystallised. Ni/amorphous iron(III) hydroxide co-precipitates transformed into Ni substituted α-FeOOH or α-Fe₂O₃, NiFe₂O₄ and α-3Ni(OH)₂.2H₂O in alkaline media. The type of reaction products formed depended on the concentration of Ni in the system and on the pH. Ni retarded the crystallisation of amorphous iron(III) hydroxide by stabilising the co-precipitate both against dissolution leading to α-FeOOH and against the internal rearrangement process which leads to α-Fe₂O₃. Chemical analysis showed that Ni was incorporated into the structure of α-FeOOH to a maximum level of 5.5 mol% and into the structure of α-Fe₂O₃ to up to 7 mol%. Excess Ni was adsorbed on the surface of the iron oxide or taken up by NiFe₂O₄ or the pure Ni phase. The b₀ dimension of the unit cell increased from 0.9960 nm for α-FeOOH to 0.9965 nm for α-FeOOH with 5.5 mol% Ni substitution. The same maximum level of Ni could be incorporated in the α-FeOOH structure in the presence of either Mn (up to 8 mol%) or Co (up to 7 mol%).     

A review on the mechanical and electrical properties of graphite and modified graphite reinforced polymer composites

Carbon materials particularly in the form of sparkling diamonds have held mankind spellbound for centuries, and in its other forms, like coal and coke continue to serve mankind as a fuel material, like carbon black, carbon fibers, carbon nanofibers and carbon nanotubes meet requirements of reinforcing filler in several applications. All these various forms of carbon are possible because of the element's unique hybridization ability. Graphene (a single two-dimensional layer of carbon atoms bonded together in the hexagonal graphite lattice), the basic building block of graphite, is at the epicenter of present-day materials research because of its high values of Young's modulus, fracture strength, thermal conductivity, specific surface area and fascinating transport phenomena leading to its use in multifarious applications like energy storage materials, liquid crystal devices, mechanical resonators and polymer composites. In this review, we focus on graphite and describe its various modifications for use as modified fillers in polymer matrices for creating polymer-carbon nanocomposites.