15%田草灵高效液相色谱分析

采用Ｎｏｖａ－Ｐａｋ Ｃ１８不锈钢色谱柱进行反相液相色谱分析，以甲醇：水＝６５：３５（Ｖ／Ｖ）为注动相，以邻苯二甲醇二乙酯为内标物，用内标法测定田草灵除草剂中苄嘧黄隆和异丙甲草胺的含量，结果表明，各有效成分与内标物色谱峰分离完全，杂质无干扰，测定结果，苄嘧黄隆和异丙甲草胺的变异系数分别为０．７４％和１．０７％，回收率分别为９９．４％￣１００．８％和９９．１％￣１０１．３％。     

Multi-label core vector machine with a zero label

Multi-label core vector machine (Rank-CVM) is an efficient and effective algorithm for multi-label classification. But there still exist two aspects to be improved: reducing training and testing computational costs further, and detecting relevant labels effectively. In this paper, we extend Rank-CVM via adding a zero label to construct its variant with a zero label, i.e., Rank-CVMz, which is formulated as the same quadratic programming form with a unit simplex constraint and non-negative ones as Rank-CVM, and then is solved by Frank–Wolfe method efficiently. Attractively, our Rank-CVMz has fewer variables to be solved than Rank-CVM, which speeds up training procedure dramatically. Further, the relevant labels are effectively detected by the zero label. Experimental results on 12 benchmark data sets demonstrate that our method achieves a competitive performance, compared with six existing multi-label algorithms according to six indicative instance-based measures. Moreover, on the average, our Rank-CVMz runs 83 times faster and has slightly fewer support vectors than its origin Rank-CVM.     

金属阳极四元涂层开发现状浅析

通过分析金属阳极涂层结构，在现有金属阳极三元涂层的基础上，确定了钌、钛、铱、锡四元涂层。对该涂层的电化性能指标及实际运行数据进行了分析，并与三元涂层电化性能指标进行对比，说明了四元涂层在析氯电位、极化率、析氧电位、寿命等方面均明显优于三元涂层，而且更适合在高电流密度下运行。     

Dynamic response of Ti3SiC2 under shock compression up to 112 GPa

Ti₃SiC₂ is of interest due to its unique dual nature reminiscent of both brittle ceramics and ductile metals at ambient conditions. In this work, plate-impact experiments have been performed to study the dynamic behavior of Ti₃SiC₂ under shock compression up to 112 GPa by using laser velocity interferometer and electric pin techniques. Hugoniot elastic limits (HEL), spall strength, and Hugoniot equations of state have been obtained based on measured particle velocity profiles and shock wave velocities. The ratio of spall strength to HEL for Ti₃SiC₂ is larger than brittle ceramics but smaller than metals. This result indicates that the dual nature of Ti₃SiC₂ remains at least up to 10 GPa. On the other hand, the linearity of the Hugoniot equation of state, $D=6.9\text{0}1(22)+1.153(53)u_{\text{p}}$, suggests that the initial structure of Ti₃SiC₂ should be stable up to 112 GPa, in contrast to the result reported by Jordan et al. [J. Appl. Phys., 93 (2003) 9639].     

Synthesis of carbon nanocapsules containing Fe, Ni or Co by arc discharge in aqueous solution

A simple, inexpensive and one-step synthesis method of metal-containing carbon nanocapsules using an arc discharge in aqueous solution is reported. It was found that Ni, Co and Fe nanoparticles could be in situ encapsulated in carbon shells when the arc was performed respectively in aqueous solutions of NiSO₄, CoSO₄ and FeSO₄. Transmission electron microscopy, energy dispersive X-ray spectroscopy and electron diffraction patterns of selected areas were used to determine the crystalline phase of the metal cores. To explain the formation mechanism of metal-containing carbon nanocapsules, a model of discharge in solution is proposed. This result presents a simply controllable way to synthesize metal-containing carbon nanocapsules.     

Electrochemical micromachining of nitinol by confined-etchant-layer technique

The confined etchant layer technique has been applied to fabricate complex three-dimensional microstructures on nitinol for the first time. HF and HNO₃ were locally and simultaneously electrogenerated at the mold surface to etch a nitinol workpiece. NaOH was used as an efficient scavenger to confine the etchant close to the mold. Cyclic voltammetry was employed to study the electrochemical behavior of a Pt electrode in the etching solution in order to choose an appropriate potential for etchant generation on the mold. The thickness of the confined etchant layer was estimated to be several micrometers by inspecting the deviation of the sizes of the etched spots from the sizes of those on the microelectrode. Thus, the composition of the electrolyte could be optimized for better etching precision. By optimizing the composition of the electrolyte, complex microstructures on a Pt-Ir mold bearing the logo “XMU” of Xiamen University were successfully fabricated on nitinol. The etched patterns were approximately negative copies of the mold, and the precision of duplication could easily reach the micrometer scale.     

物理防晒剂配方应用

指出了防晒对人体的重要性，并给出了防晒产品提高效能的依据。重点讨论了如何使用TIOVEIL和SPECTRAVEIL分散液来取得最佳的效能，在达到最高的SPF值和UVA防护的同时保证最终产品的稳定和雅致外观。同时还给出了物理防晒产品TIOVEIL和SPECTRAVEIL的配方指导。