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This study aims to obtain safe working condition of the electrothermal U-shaped actuator (EUA). The finite difference method is applied for modeling and solving the steady electric-thermal state and maximum temperature of the microactuator. The critical voltages causing beam buckling and overheating phenomena are determined to avoid the axial instability as well as melting deformation of the actuator. The relationships between temperature and the frequency or amplitude of the AC are analyzed. The results showed that the structure and the applied voltage levels have significant influence on the temperature distributions and the value of the stress. It is confirmed that the temperature between 300 to 600 °C is comparatively suitable for microactuator according to theoretical and experimental analysis, and the microactuator is able to provide accurate and stable number of cycles for tens of millions. [ABSTRACT FROM AUTHOR]

We study the sum of the finite multiple harmonic q-series on r-(r + 1) indices at roots of unity with r = 1, 2, 3. Mainly, we give equivalent conditions of two conjectures regarding cyclic sums of finite multiple harmonic q-series on 1-2-3 indices at roots of unity, posed recently by Kh. Pilehrood, T. Pilehrood and R. Tauraso. [ABSTRACT FROM AUTHOR]

White type Channa argus, which has the common name of the great northern snakehead, has an uncertain classification for many years. In the present study, mitochondrial COI gene has been used to analyze the relationships and genetic diversity of nine kinds of Channa. For the Chnannidae family, the average of the inter-species genetic distance was 0.156 (ranged: 0.000–0.245). And the intra-species genetic distances were ranged from 0.000 to 0.002. For the haplotypes of two-colour morphs of Channa argus, the mean of the pair-wise genetic distances was estimated as 0.0009. This value was within the intra-species genetic distance interval, indicating that two-colour morphs of Channa argus are not subspecies of white type at the molecular level. Moreover, take Lateolabrax maculates and Epinephelus coioides as outgroups, molecular phylogenetic tree showed that all the haploids gather together as a branch and crossing each other. These indicated that the white type Channa argus should be regarded as an albino of bio colour type. [ABSTRACT FROM AUTHOR]

As an unclassified species, white-type Channa argus has existed for many years. In the present study, the relationships and genetic diversity in two colour morphs of northern snakehead were determined by the analysis of mitochondrial 12S rRNA gene, as well as other Channa species. The results of sequence analysis showed that the average genetic distance was 0.046 with the interspecies genetic distance ranging from 0.000 to 0.130; and the average interspecies genetic distance was estimated as 0.003 (range: 0.000-0.006). For the two colour morphs of Channa argus, the mean pair-wise genetic distance between them was also estimated as 0.003. Moreover, molecular phylogenetic tree was constructed using MEGA6.0, which showed that all the haploids gathered together as a branch and crossed each other. These results indicated that the white and biocolour-type Channa argus belonged to the same species, rather than subspecies at the molecular level, and the white-type Channa argus should be regard as an albino of biocolour type. [ABSTRACT FROM AUTHOR]

The contact mechanism of contact pair in microscale is widely studied both in micro tribology and micro technology. This paper introduced a micro gear mechanism (MGM) for studying the micro-scale adhesive contact between the micro gear pairs based on the Johnson-Kendall-Roberts (JKR) contact model, and analyzed the energy conversion and dissipation process during the tooth meshing process. The MGM was fabricated by using PolyMUMPs surface micromachining technology. The driving conditions of MGM established by considering adhesive contact deformation energy, energy dissipation and elastic deformation energy, has been analyzed. The displacement and force of bi-directional actuator for driving the gear to rotate one tooth can be achieved when temperature increment is above 600 °C according to the driving conditions of MGM. The experiment results showed that motion of MGM is successfully achieved. This work provides a comprehensive understanding of the transmission behavior of the MGM. The model will be useful for designing micro-gear devices. [ABSTRACT FROM PUBLISHER]

As the power producer, the microactuator is an important part of Micro Electro Mechanical Systems, which is used for the energy conversion, motion and force producion. The function and performance of MEMS are deeply affected by the micro-actuator's output ability of displacement and force. In this paper, a bi-directional electrothermal microactuator which can generate displacements in both x and y direction is designed. Static theoretical model of bi-directional actuator is established via electro-thermal analysis and thermal-structural analysis. The static theoretical model is preliminary validated by comparing the theoretical values with simulation and experimental results. We also study the application of micro transmission mechanism based on bi-directional electrothermal microactuator. [ABSTRACT FROM AUTHOR]

Reliability of MEMS is essential to its successful application. This paper focused on the failure mode of MEMS, the reliability test and modeling of MEMS and the reliability test method of typical devices. Designing of MEMS reliability is discussed based on the review of MEMS reliability test and the failure model of MEMS reliability. In this paper, firstly, recent development in MEMS reliability field is elaborated. Secondly, research of MEMS reliability aimed at different typical MEMS mechanism and devices is summarized in three major areas: several common kinds of the failure mode of MEMS, MEMS reliability model and MEMS reliability test of typical MEMS mechanism and devices. Finally, the main direction of MEMS research and the research trend in the future is discussed. [ABSTRACT FROM AUTHOR]

With the rapid development of MEMS fabrication technology, the function of transferring motion and force for micro transmission mechanism has been basically implemented. The micro transmission mechanism could mainly be driven by micro actuators, through several transmission parts such as micro link, micro hinge and micro gear, to transfer motion and force. Research status and working principle of micro transmission mechanism in the recent twenty years are summarized in detail. Research status and research achievements about design and transferring motion are introduced. In addition, the key technology, existing problems and application prospect of micro transmission mechanism are analyzed. [ABSTRACT FROM AUTHOR]

In this study, we show the complete chloroplast genome in G. elegans by high-throughput sequencing. The chloroplast genome in G. elegans is 155,018 bp in size, comprising a pair of inverted repeats (IRa and IRb) of 25,728 bp each and an LSC region of 85,619 bp and an SSC region of 17,943 bp. The genome includes 117 single-copy genes (29 tRNA, 8 rRNA genes and 80 protein-coding). Phylogenetic analysis using total chloroplast genome DNA sequence of 15 species belonging to Gentianales showed that Apocynaceae and Loganiaceae form a single cluster with closer relationship to Gentianaceae than with Rubiaceae. [ABSTRACT FROM AUTHOR]