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101.
温度和pH对硼在水溶液中的溶解有一定的影响。随着温度的升高,8≤pH≤11的硼水溶液,硼的饱和浓度随之增加,而pH为12时,硼的饱和浓度先增大后减小。随着溶液pH增大,30 ℃≤温度≤60 ℃的硼水溶液,硼的饱和浓度先减小后增大,而温度为70 ℃时,硼的饱和浓度表现为先减小后增大再减小的趋势。实验采用Raman光谱仪和X射线衍射仪对含硼饱和水溶液及沉淀固相进行了分析,探讨了含硼饱和水溶液液相及沉淀固相中硼氧配阴离子的存在形式和相互作用机理。结果表明,当溶液pH较高时,有利于低聚合度硼氧配阴离子的存在,其形式主要为B(OH)4-、B2O(OH)62-。  相似文献   
102.
Global economic and pollution concerns are having a major impact on how modern engine oils are being formulated. Modern engine oil specifications mandate reduced levels of phosphorus and sulfur to protect the efficacy of pollution control devices. In addition, modern engine oil must also be more fuel efficient than earlier generations to reduce greenhouse gas emissions and the impact of high priced gasoline and diesel fuel to the consumer. At the same time, oxidation, wear, and corrosion performance of the oil must not be compromised. Multifunctional additives are useful formulation tools that help formulators meet these tough new challenges. One such additive is the organo-borate ester/amide. Originally conceived as an organic friction modifier, this patented technology is really a multifunctional additive that addresses the global economic and pollution concerns. With the addition of boron, this unique commercial organic friction modifier also imparts antioxidancy, antiwear and anticorrosion properties to engine oil. In addition, the organo-borate ester/amide is compatible with pollution control devices because it does not contain sulfur or phosphorus. Work is on going to uncover additional beneficial properties of this chemistry.  相似文献   
103.
含硫磷硼酸酯衍生物的制备及其在合成油中的摩擦性能   总被引:1,自引:0,他引:1  
实验通过在硼酸酯结构中引入硫代磷酸酯官能团,成功制备了一种含硼添加剂,并在合成基础油中考察了其摩擦学性能:在合成油中的抗磨性能较二烷基二硫代磷酸锌较差,而减摩性能好于二烷基二硫代磷酸锌。初步考察了该含硼添加剂的抗氧化性能及热稳定性。  相似文献   
104.
Preparation and Performance of Overbased Complex Sulphonates   总被引:1,自引:0,他引:1  
Overbased complex sulphonates containing two metals - sodium and magnesium - were prepared by using overbased magnesium sulphonate as the starting material. Borated overbased complex sulphonate containing two metals was synthesized by reaction of boric acid with the corresponding sulphonate. The total base number (TBN) of overbased complex sulphonates decreased compared with that of magnesium sulphonate, while TBN of borated overbased complex sulphonate further decreased. The detergency, anti-oxidation and extreme pressure performances of overbased complex sulphonates were improved compared with those of overbased magnesium sulphonate; the anti-oxidation and extreme pressure performances of borated overbased complex sulphonates were further improved whereas its detergency was reduced.  相似文献   
105.
Optical and FT infrared spectral properties of tungsten ions in a host lead borate glass with composition PbO 55%, B2O3 45% (wt%) were studied. The same spectral properties were re-measured after subjecting the samples to successive gamma irradiation. The work was undertaken to justify the state of tungsten ions in such glass system by combined spectral investigations. Optical and FTIR spectral studies were confirmed by investigating electron spin resonance (ESR) of the undoped and WO3-doped samples before and after gamma irradiation. The optical spectrum of the undoped glass exhibits strong and wide UV absorption bands, which are related to the combined UV spectra of trace iron impurities (Fe3+ ions) and that from divalent lead (Pb2+) ions. Optical studies of WO3-doped sample indicate the presence of tungsten ions mostly in the hexavalent W6+ state. The presence of tungsten ions as structural groups was obtained by comparing the FTIR spectra of the undoped and WO3-doped samples. ESR spectra confirm the optical and FTIR spectral studies. The studied host lead borate glass has been found to show obvious shielding behavior towards successive gamma irradiation as revealed by the constancy of optical absorption spectral curves.  相似文献   
106.
锂离子电池用双草酸硼酸锂的固相合成   总被引:1,自引:0,他引:1  
详细介绍了固相法合成的一种新型电解质锂盐--双草酸硼酸锂(LiBOB)。制备过程采用草酸、氢氧化锂、硼酸为原料,其物质的量比为2.1∶[KG-*2]1∶[KG-*2]1,经球磨混合后高温烧制,烧制温度为120 ℃、脱水温度为240 ℃,所得产品经乙酸乙酯提纯后即得产物。产物通过分析测定可知,其杂质含量少且晶体结构完整;并通过热分析证实其热稳定性优于六氟磷酸锂。用其制备的电解液组装的电池,循环性能较好,所制双草酸硼酸锂达到用作电池电解质锂盐的标准。  相似文献   
107.
Lithium difluoro (oxalate) borate (LiDFOB) is used as thermal stabilizing and solid electrolyte interface (SEI) formation additive for lithium-ion battery. The enhancements of electrolyte thermal stability and the SEIs on graphite anode and LiFePO4 cathode with LiDFOB addition are investigated via a combination of electrochemical methods, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared-attenuated total reflectance (FTIR-ATR), as well as density functional theory (DFT). It is found that cells with electrolyte containing 5% LiDFOB have better capacity retention than cells without LiDFOB. This improved performance is ascribed to the assistance of LiDFOB in forming better SEIs on anode and cathode and also the enhancement of the thermal stability of the electrolyte. LiDFOB-decomposition products are identified experimentally on the surface of the anode and cathode and supported by theoretical calculations.  相似文献   
108.
In order to sensitize the luminescence of Eu3+ ions in heavy metal glass,zinc lead borate glass samples containing various concentrations of Eu3+ and Tb3+ ions were prepared to study the Tb3+ to Eu3+ non-radiative energy transfer phenomena.Energy level structures of Tb3+ and Eu3+ ions were plotted to show the excitation and energy transfer routes.Efficient energy transfer from Tb3+ to Eu3+ was observed and studied qualitatively in terms of doping concentrations.The sensitization turned out to be less effective than expected.Further studies to characterize the oxidation of Tb3+ into tetravalent state and to examine the mechanism of energy transfer are proposed.  相似文献   
109.
以二甲胺和硼酸为原料,通过水热反应合成有机模板硼酸盐[C2H8N][B5O6 (OH)4],通过单晶X射线衍射对其晶体结构进行分析,该晶体属于单斜晶系,空间群为C2/c,晶胞参数为a=1.3381(75) nm,b=1.1468(56)nm,c=1.7137(92) nm,α=90.032(64)°,β=112.292(82)°,γ=89.988(85)°,V=2.433(2.000) nm3.粉末衍射(PXRD),红外(IR),热重(TGA)以及荧光(PL)等手段对其晶体进行分析表征.在不同温度下对该物质进行热处理,观察其IR和PXRD的变化判断其内部的结构是否能够保持稳定,并通过热重分析进行补充说明.荧光光谱结果表明在经过不同温度热处理后,该物质的发光特性发生明显的变化.实验证实[C2H8N] [B5O6(OH)4]一种可能用在白光LED上的荧光粉.  相似文献   
110.
硼酸镁晶须的制备与应用研究   总被引:1,自引:0,他引:1  
系统地介绍了硼酸镁晶须在制备工艺及其应用技术领域的国内外研究现状,通过详细对比分析当前各种硼酸镁晶须的制备方法,回顾硼酸镁晶须的应用范围和增强效果,指出了硼酸镁晶须在制备、应用中存在的问题,以期对中国硼酸镁晶须的开发和综合利用起到促进作用。最后就硼酸镁晶须今后的发展趋势作了展望。  相似文献   
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