一种MEMS平板型同位素微电池的设计与制作

针对倒三角直槽型或倒金字塔型能量转换结构的同位素微电池难于加工以及放射性薄膜不均匀等缺陷,设计了一种较为简单的平板型能量转换结构.引入金属区这一结构,增强了放射源薄膜的接触稳定性.63Ni放射源电镀实验最终得到了一组理想的短路电流和开路电压数据.结果表明,该结构与传统的能量转换结构相比有更稳定的功率输出.     

微通道板电极表面的XPS分析

为探索微通道板的噪声来源，利用Ｘ射线光电子能谱对国内和国外ＭＣＰ电极表面进行组分分析。实验发现，在国外ＭＣＰ电极表面上只检测Ｎｉ，Ｃｒ，Ｃ，Ｏ等谱峰，而在国内的ＭＣＰ电极表面还检测到Ｋ，Ｎａ，Ｓｉ等原子谱峰，且在国产未镀电极的ＭＣＰ表面检测出Ｋ的原子谱峰。     

微通道板电极表面的XPS分析

为探索微通道板的噪声来源，利用X射线光电子能谱对国内和国外MCP电极表面进行组分分析。实验发现，在国外MCP电极表面上只检测到Ni，Cr，C，O等原子谱峰，而在国内的MCP电极表面还检测到K，Na，Si等原子谱峰，且在国产未镀电极的MCP表面检测出K的原子谱峰。分析认为，MCP体内的K有向表面偏析的现象；MCP电极表面上的杂质，如K，Na，Si等是MCP噪声来源之一；国产MCP表面的杂质不仅与MCP镀膜材料纯度、系统真空度有关，而且还与电极膜层的致密性有关。     

一种新型基于MEMS的同位素微电池的研究

介绍了同位素微电池的工作原理及结构组成.阐明了其从工作原理上区别于原有的核电池,采用和太阳能电池光生伏特相似的辐生伏特效应.对同位素微电池的工艺作了详尽的介绍.提出了使用垂直侧壁方孔阵列的能量转换结构,相比传统的同尺寸开口且等深的倒三角直槽型或倒金字塔型的能量转换结构表面积增大了120%以上;引入了电镀区这一新结构,增强了同位素微电池的工作稳定性.     

金属钴对储氢合金电极的表面修饰研究

运用真空蒸镀法时MH／Ni电池储氢合金电极进行了镀覆金属钴的表面修饰,测试了电池的放电容量、高倍率放电性能、循环寿命和充电时的内压,利用XPS和XRD时电极进行了表面和结构分析。实验结果表明,运用该方法对电极进行表面修饰可以降低电池内阻,提高电池的放电容量和放电电压,极片经过修饰的电池,5C（8．5A）放电容量提高了120mAh,放电平台电压提高了约0．05V,内阻降低了19．3％。极片经过表面镀钴后,显著改善了电池的循环性能,电池500周循环后的放电容量仍为初始容量的94．09／6,同时,电池在充电时的内压有了明显的降低,充电效率有了较大的提高。     

新电极材料助力锂离子电池提高效率

美国莱斯大学机械工程和材料科学领域的Pulickel Ajayan教授领导的研究团队利用自身开创的一种工艺过程，制备出一种新型的同轴电缆：壳层为二氧化锰，芯层为碳纳米管。该过程无需使用目前在电池中普遍用到的粘合剂，其作用是聚集组分，但与此同时会引起导电性能下降。     

水溶液锂离子电池电极材料的发展概况

通过对水溶液锂离子电池电极材料的制备方法、结构、电化学性能、充放电过程等方面的论述,总结了近年来水溶液锂离子电池电极材料的研究状况,并对存在的问题进行了分析。探讨了采用不同化合物、不同制备方法和改性方法来提高其比容量和循环稳定性的可能性。     

沟槽型微纳复合结构表面的制备与减阻性能研究

沟槽微结构减阻与疏水表面减阻是两种有效的水下减阻技术。将两种典型的减阻技术进行联合协同，在聚对苯二甲酸乙二醇酯-1,4-环己烷二甲醇酯(PETG)基底表面采用激光微刻方法构筑微米级沟槽结构，采用二步喷涂法先后在微沟槽表面覆盖环氧树脂层与改性的纳米SiO₂颗粒，从而实现沟槽型微纳复合结构表面的制备。利用接触角测量仪、体视显微镜、拖曳式摩擦阻力测试设备对复合结构表面的润湿性、水下气膜状态及水下减阻性能进行表征。结果表明，沟槽型微纳复合结构表面为超疏水表面，液滴在该表面处于“Cassie-Baxter”润湿状态;在水下，复合结构表面具有束缚大尺寸气膜的能力，气膜驻留于表面沟槽之中且促使了表面的水下减阻效果的产生;对比单纯的沟槽微结构表面与喷涂SiO₂颗粒光滑表面，制得的沟槽型复合结构表面在沿垂直于沟槽方向运动时最大减阻率可达20.82%，同时表面气膜的稳定性也最佳。     

新纳米微电池充电比锂电池更快

赖斯大学发明的这种纳米结构的锂电池与现在通用的锂电池相比,充电更迅速、电力也更充足。右侧的透射电镜图显示,纳米线被一种PMMA的多聚体包裹着。美国赖斯大学的科学家最近在微电池制造方面迈出了重要的一步,他们研发出一种结实的立体微电池,这种电池比普通的锂电池充电时间更短,其他性     

锂离子电池用中间相炭微球的低温表面修饰

采用CoCl2对中间相炭微球进行低温表面修饰,进行了表征和性能测量,并研究对其性能的影响.结果表明,低温热处理中间相炭微球仍以低温炭结构为主,但是微球表面的碳微晶尺寸比内部的大;低温表面热处理能够明显提高中间相炭微球的可逆容量,在不降低充电容量的情况下将首次库仑效率从52.2%提高到87.2%,并改善了循环性能.低温表面修饰使中间炭微球表面碳结构的有序化程度增强,有效地缓解了碳表面的不可逆电化学反应.     

A two-step deposition process for electrode fabrication of CdZnTe detectors

The method of the electrode deposition process plays a vital role in determining the contact characteristics, which is often one of the dominant factors influencing the CdZnTe detector performance. In this work, a modified deposition process named two-step process for the electrode fabrication of CdZnTe detectors, was developed. This deposition process can dramatically increase the adhesion strength and reduce the inhomogeneity of the metal/semiconductor interface, and improve the detection ability of high energy radiation such as X-rays and gamma-rays. Scanning acoustic microscopy, shear tests, current-voltage test and energy spectra characteristics measurements were carried out in this work.     

Sol-gel microsphere pelletization: A powder-free advanced process for fabrication of ceramic nuclear fuel pellets

Hydrated gel-microspheres of U, Pu, Th oxide or oxide plus carbon mixture of diameter 400–800μ were prepared by ammonia gelation processes. They were dried and subjected to suitable treatment for obtaining free-flowing oxide, carbide or nitride micro-spheres of diameter 200–400μ suitable for direct pelletization and sintering. The oxide, carbide and nitride pellets were, in general, sintered at high temperature in Ar+8% H₂. However, for UO₂ and (U, Pu)O₂ pellets low temperature (1200 °C), short duration (1 h) oxidative (CO₂ or N₂+air) sintering (LTS) was also successful, thereby reducing electrical energy and gas consumption during sintering. Thus, the combined SGMP-LTS process simultaneously minimized “radiotoxic dust hazard” and fuel fabrication cost in case of UO₂ and (U, Pu) O₂ pellets.     

A modified TSIG technique for simplifying the fabrication process of single-domain GdBCO bulks with a new kind of liquid source

The top seeded infiltration and growth process (TSIG) is an effective way for the preparation of bulk REBa₂Cu₃O_7−x (RE-123) with finely dispersed RE₂BaCuO₅ (RE-211) particles compared to the conventional melt growth (MG) method. However, it is more complicated and time-consuming because three kinds of precursor powders, involving RE-211, RE-123, and BaCuO₂, have to be prepared before the conventional TSIG process. In this article, a new liquid source (NLS) composed of RE₂O₃ (RE-200), BaCuO₂, and CuO powders, has been found for simplifying the TSIG process, which is different from the regular liquid source (RLS) composed of RE-123 and Ba₃Cu₅O₈. In this modified TSIG technique, what we need is only to prepare RE-211 and BaCuO₂ precursor powders for the whole TSIG flow. Single-domain GdBCO bulk superconductors have been fabricated using the RLS and NLS separately. The morphology, microstructure, and levitation force of the GdBCO bulks have also been investigated. The results indicate that the NLS can be used to simplify the process flow, reduce the cost and improve the efficiency on the fabrication of single-domain GdBCO superconductors.     

A facile solution-immersion process for the fabrication of superhydrophobic surfaces with high water adhesion

The present work reports a simple and effective way to produce copper compound films on zinc substrate via solution-immersion process. The surfaces were characterized by field-emission scanning electron microscopy, Fourier transform IR, X-ray photoelectron spectrum and X-ray powder diffraction. The wettability of the surfaces is also investigated. The as-prepared superhydrophobic surfaces exhibit high adhesion to water and scratches on the surfaces could be repaired by immersing the damaged samples into the solution again.     

A novel submicron-gap electrode fabrication technology using thermal oxidation

A novel and reproducible method to fabricate submicron-gap electrodes using thermal oxidation has been presented. In this method, oxidation process determines the gap distance. The micron-level silicon electrode gaps with different shapes were first generated on the silicon wafer by conventional photolithography followed by deep reactive ion etching process. Then thermal oxidation was conducted to realize the transition from silicon to silicon dioxide, i.e. reduce the gap width. Finally, the planar electrodes with sub-micron spacing were formed by metallization and photolithography. Scanning electron microscopy (SEM) was used to examine the electrode configuration and the electrical properties of as-prepared electrode pairs were also characterized. The results showed that using the method investigated in this work, Au electrodes with a submicron-sized gap could be easily fabricated, with good uniformity and reproducibility.     

Dynamic silica assembly for fabrication of nanoscale polymer channels

Nanoscale polymer silica hybrid nanochannel array of average channel size of ∼50 nm were fabricated by electrokinetically induced silicification reaction within a polymer template. The uniform growth of silica can be realized by appropriate combination of reactant concentration and electric field strength. The formed silica leads to the reduction in channel size, and provides substantial reinforcement to the polymer nanostructure. Such nanochannel arrays may be a useful platform for a variety of biomedical applications.     

A novel,environmentally friendly process for the fabrication of calcium phosphate bioceramics

Problems are addressed that relate to the use of standard processes (involving several consecutive steps) for the fabrication of calcium phosphate bioceramics: process duration (up to 72 h), low chemical yield (notably lower than 100%), and a large amount of byproducts (largely in the form of alkaline (pH ∼ 10) aqueous solutions). A new, environmentally friendly, one-step process is proposed for the preparation of calcium phosphate bioceramics. Original Russian Text ? S.V. Dorozhkin, 2008, published in Neorganicheskie Materialy, 2008, Vol. 44, No. 2, pp. 253–256.     

A facial microwave-assisted polyol activation process for fabrication of Ni@PMMA microspheres

A simple and efficient activation process was conducted by deposition of palladium (Pd) nanoparticles on PMMA surface using a microwave-assisted polyol method with ethanol used as the reductant. The newly synthesized Pd nanoparticles were utilized as an activator for electroless nickel deposition. TEM images revealed that Pd nanoparticles of size 4-6 nm are formed evenly over the PMMA surface. A tight, smooth and continuous Ni plating layer was coated on these Pd nanoparticle activated PMMA microspheres. In contrast, a rough and discontinuous Ni film was obtained for the sample activated with a conventional sensitization/activation procedure.