锑掺杂二氧化锡薄膜的导电机理及其理论电导率

归纳总结了锑掺杂二氧化锡(ATO)的导电机理。晶格的氧缺位、5价Sb杂质在SnO2禁带形成施主能级并向导带提供n型载流子是ATO导电的两种主要机理。从材料的电导率公式出发,定性分析了二氧化锡中掺杂锑的含量存在理论最佳值,根据已有模型计算证明了锑掺杂二氧化锡电导率存在理论上限。掺杂二氧化锡中锑的最佳理论含量为1.49%(质量百分数),锑掺杂二氧化锡理论电导率最高为0.217×104(Ω·cm)-1,氧空位对ATO电导率的贡献为0.1506×104(Ω·cm)-1。     

泵类电机变频调速节能及运行分析

变频调速是目前国内较先进的一项电机控制技术，逐步在工业生产申得到推广应用。对流量需变化的泵类负载电机，其应用前景更为广阔。泵类负载传统的流量调节方法是：启闭管道闸阀或档板。传统方法不利于电网及拖动电机的经济运行，电机负载率低。应用变频调速技术控制泵类负载电机，在保证相同负载要求的情况下，与传统方法相比，可提高电机负载率及效率，达到节能之目的；同时，可以改善电机运行性能。通过应用日本富士公司生产的FRENIC5000G7／P7型变频器效果表明：其节电率大于20％，电机运行性能得到改善。究其原因，关键在于该变频器采用了磁通控制式PWM控制（转矩提升控制）技术及启动频率0．5～5Hz可调，并应用微处理器实行实对控制。     

锌火法精炼加铝除铁的工业试验

针对锌精馏工艺中熔析硬锌产出率高,硬锌回收困难的问题,在理论分析的基础上进行了加铝除铁的工业试验,硬锌产出率从2.5%降至0.5%。     

Thermodynamics of solubility of Cu_2(OH)_2CO_3 in ammonia-ammonium chloride-ethylenediamine(En)-water system

In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper c...     

甲基磺酸体系铅电沉积工艺研究

针对传统铅电沉积体系稳定性差、环境污染严重、腐蚀性强等问题,提出采用甲基磺酸(MSA)体系电沉积铅,考察了电流密度、铅离子浓度、MSA酸度、温度和极距对电沉积过程的影响。结果表明,在电流密度200 A/m²、铅离子浓度150 g/L、MSA酸度50 g/L、温度45 ℃和极距3.5 cm的条件下,可获得平整光亮、结构致密的铅板,纯度可达99.98%,此过程电流效率高于99%,能耗为612 kWh/t,相较于传统硅氟酸体系能耗(800 kWh/t)降低了188 kWh/t。该体系具有稳定性强、不含卤素和节能环保等优点,具有较为广泛的应用前景。     

Thermodynamic calculation of Sn (Ⅳ)-NH4+-Cl--H2O system

According to the principles of simultaneous equilibrium and electronic charge neutrality, the thermodynamics of Sn(Ⅳ)-NH4 -Cl- -H2O system under normal condition was calculated. Relation between all sorts of complex of Sn4 and pH was plotted. Based on thermodynamics analysis and calculation, some experiments were done to validate the relation between the total concentration of tin ion and pH in this system. The results suggest that the total concentration of ammonium and pH are the most important factors which determine whether (NH4)2SnCl6 or Sn(OH)4 exists in this system. Results further suggest when contnet of HCl is more than 6 mol/L, Sn4 in this system will be also precipitated in the form of (NH4)2SnCl6. These results lay the solid theory foundation to preindium tin oxide(ITO), from the tinny material.     

Electrochemical synthesis and characterization of tantalum alkoxides

Tantalum(V) propoxide (Ta(OPrⁿ)₅), isopropoxide (Ta(OPrⁱ)₅) and butoxide(Ta(OBuⁿ)₅) were synthesized by electrochemical reactions of corresponding alcohol at sacrificial tantalum anode in the presence of tetraethylammonium chloride as a conductive additive. The pure products were isolated by reduced pressure distillation under 5 kPa. The crystal of Ta(OPrⁱ)₅ was obtained by recrystallization from hexane at ?10 °C. These samples were characterized by Fourier transform infrared spectra (FT-IR), Raman spectra, nuclear magnetic resonance spectra (NMR), TG/DTA and ICP-MS. The results show that direct electrochemical synthesis of metal alkoxides has a high current efficiency and electrolysis yield. These alkoxides have a high purity of 99.97% and can be directly used as the precursor of Ta₂O₅ films.     

Preparation of high-purity tantalum ethoxide by vacuum distillation

Effects of reflux ratio, water addition and content of water in ethanol on the purity and yield of tantalum ethoxide during vacuum distillation were investigated under the operational conditions of pressure of 1kPa, oil bath temperature of 210-230 ℃, and outlet temperature of 190℃. The condensate sample was characterized by FTIR, 1↑H-NMR spectroscopy and Raman spectra, respectively. The contents of tantalum, carbon and hydrogen in the sample were also determined with elemental analysis instrument. The obtained results consistently demonstrate that the condensate is tantalum ethoxide. The content of impurity, such as Al, As, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sn, Ti, V and Zn, in tantalum ethoxide is less than 0.000 05%, while Nb content is less than 0.000 5%. The content of impurities in tantalum ethoxide sample excels that of Epichem Group＇s requirement for Ta（OC2H5）5 of 99.999%.     

Synthesis of ultrafine copper particles by complex-reduction-extraction method

A novel chemical process for producing well-defined copper particles with satisfied anti-oxidation property was described. The resultant particles were characterized by X-ray diffractometry and scanning electron microscopy. The results show that well-dispersed nano-copper particles with 70 nm in diameter are obtained from the water/organic solution containing 0.2 mol/L Cu2. ion, with ammonia as ligand and ascorbic acid as reductant. In this process, the formation of copper-ligands in aqueous solution causes initial copper ions concentration very low, which is not only good to obtain homogeneous initial reaction solution, but also slower the initially drastic nucleation reaction rate. This makes the process more convenient for delaying the nuclei processes and for controlling the ultimate copper particles size. In addition, oleic acid acts as both a phase-transfer agent and a particle protector coordinating their carboxyl end groups on the new generated copper particles surface, the carbon tails of the oleic acids are pointed outwards from the surface of the synthesized particles. This organic film also seems to play an important role to prevent the new generated copper particles from oxidation.     

矿物共沉法制取低功耗软磁铁氧体扩大试验研究

以铁屑、软锰矿和氧化锌烟灰为原料，进行了10kg/次规模的直接法制取低功耗软磁共沉粉的实验室扩大试验。实验结果表明：共沉粉杂质元素含量低，配比准确，活性好；经铁氧体工艺试验证明，所制锰锌软磁铁氧体产品的性能超过PC30，接近PC40．