铜基体镀金层大气变色机理分析及对策

本文对电连接器镀金接触体可能经常发生的表面红(黑)斑点现象进行了描述,结合现代的微观分析手段,从化学热力学和动力学两个层面进行了分析,为业界提供解决该类问题的思路及一般方法,减少制造业不必要的损失,希冀对社会可持续发展有所贡献.     

车载黑匣子基于无可信中心秘密共享的安全解码

车载黑匣子能记录车辆的行驶数据,是交通事故责任判定的重要依据,因此设计安全的黑匣子非常重要.基于秘密共享和椭圆曲线密码,提出高安全的黑匣子编码和解码模型.模型由秘密分发、安全编码、协同解码、秘密份额更新、联合颁发份额五个协议组成.协议族保证了车载数据的机密性和完整性,在无可信中心的前提下,实现了解码组成员的协同解码,解...     

纳米颗粒在有序多孔陶瓷中的行为研究

本文详细研究了纳米颗粒在有序多孔陶瓷中形成协同体的过程。实验结果表明:纳米TiO2和炭黑(CB)能比较容易进入到有序多孔陶瓷中形成具有特定功能的协同体。当纳米TiO2的浓度增加到5wt%和炭黑浓度增加到15 wt%时,有序多孔陶瓷的孔壁上粘附纳米TiO2和炭黑颗粒的量最大从而形成大量的活性点;浓度对两种纳米颗粒的渗透力具有很大的影响,炭黑粒子的渗透能力比纳米纳米TiO2颗粒强。     

铝件镀银出现“黑斑”的原因及其消除

某批次铝零件在镀银后喷漆加工过程中出现了黑斑.从原材料、电镀和喷漆加工工艺等方面对黑斑产生的原因进行了讨论,通过表面和截面形貌观察、电镜分析、能谱分析等方法对黑斑与正常镀银层进行了对比,确定了黑斑为镀银层被硫元素污染所致,并找出了镀银层变色的原因,排除了故障.     

十二烷基苯磺酸钠辅助尿素共沉淀制备超细铜铬黑颜料

以十二烷基苯磺酸钠为表面活性剂,采用尿素共沉淀法合成超细尖晶石型铜铬黑颜料。以铬和铜硝酸盐为原料,系统研究了沉淀剂、煅烧温度和表面活性剂等条件对铜铬黑颜料晶型、形貌和粒度的影响;并探讨了合成条件对铜铬黑颜料着色力的影响。研究表明,尿素和十二烷基苯磺酸钠可有效地控制形貌、颗粒大小及均匀性;在尿素用量为理论量4倍、表面活性剂添加量为5%、煅烧温度800℃的条件下制备出了形貌为六面体、平均粒径为300 nm、粒径分布均匀、着色力优异的超细铜铬黑颜料。     

用热胀离解探讨炭黑/白炭黑与天然橡胶的作用力

将炭黑DZ 13、N 330和N 660及改性的白炭黑TB2和通用白炭黑填充的天然橡胶(NR)在二甲苯中于不同温度下进行离解,外推其离解温度,并通过傅里叶变换红外光谱和热重分析等手段判断填料与橡胶分子链之间的界面结合强度。结果发现,利用溶剂溶胀法外推出的炭黑DZ 13/NR、炭黑N 330/NR和炭黑N 660/NR的结合胶完全离解温度分别为360,334,220℃,表明炭黑DZ 13与NR的化学结合力较强。虽然白炭黑/NR结合胶的离解曲线与炭黑结合胶有所不同,但其外推的完全离解温度均比炭黑低,说明改性白炭黑随着温度的升高,其表面的改性剂在溶剂中被逐渐溶解,从而造成了橡胶分子链的脱离。     

Hydrogen production from thermo-catalytic decomposition of methane using carbon black catalysts in an indirectly-irradiated tubular packed-bed solar reactor

The solar thermo-catalytic decomposition of methane using carbon black catalysts for CO₂-free hydrogen production is studied in a packed-bed reactor. The indirectly-irradiated reactor is based on a cavity receiver and a tube-type absorber in which a given load of particle catalyst is injected during on-sun operation, while enabling multiple refilling for catalyst replacement. Concentrated solar power is used as an external radiative source for supplying the high temperature process heat and for driving the endothermic reaction. The indirect irradiation via the intermediate opaque tubular absorber results in a more uniform heating of the whole reacting bed volume and thus an easier reaction temperature control and determination. Carbon particles are used for enhancing the rate of the heterogeneous decomposition reaction and the coupling of the reactor with a particle injection system is implemented to operate in semi-continuous mode with possibility of catalyst load renewal after deactivation.     

铸造浇铸油烟治理的研究

铸造浇注和铸件冷却通段的焦油油烟、黑烟等,易燃和有毒有害,污染环境,影响人类的身体健康。采用油烟治理净化系统,净化主体利用喷淋式填料塔,净化系统的材料耐酸碱、防腐蚀,具有噪音低、运转平稳,液气充分接触,废气被吸收净化,造价低、效率高的特点,达标排放污染物。     

钛白废酸浓缩副产物“黄泥巴”制铁黑工艺的研究

钛白废酸浓缩副产物"黄泥巴"是钛白生产过程中形成的一种危险废弃物。其具有成分复杂,杂质含量多,储藏和运输不便等特点,不能作为产品直接销售。笔者通过多次深入研究和实验,探索出了"黄泥巴"制取高蓝相铁黑颜料的工艺条件。     

CHARACTERIZATION OF PETROLEUM RESIDUA THROUGH REDUCTIVE CHEMISTRY

ABSTRACT

Distillation residua from petroleum, containing 26 — 32% aromatic carbon (f_a), are reduced by K⁰ in tetrahydrofuran to form anions which are then alkylated by alkyl iodides. Consumption of potassium in 24 hours at room temperature is in the range 4 to 5 mmol K per gram resid, of which 19—23% goes to the formation of “K₂S” from the removal of sulfur from the resid. The anions of the resid are characterized by alkylation of the resid with ¹³C enriched methyl iodide followed by examination by heteronuclear correlated two—dimensional nuclear magnetic resonance of ¹H and ¹³C spins. Analysis of proton and carbon shifts of individual methyls demonstrates that attachment of methyls to carbon atoms of the resid is the principal chemistry of the reductive methylation.