Selection of the Optimal Cooling Parameters to the Multi-Cavity Die

This study is subject to the finite element and abd uc tive network method application in the multi-cavity die. In order to select the optimal cooling system parameters to minimize the warp of a die-casting die, t he Taguchi‘s method and the abductive network are used. These methods are appli ed to create an efficient model with functional nodes for the considered problem . Once the cooling system parameters are developed, this network can be used to predict the warp for the die-casting die accurately. A ...     

Cenozoic stratigraphy of Taiwan: Window into rifting, stratigraphy and paleoceanography of South China Sea

Shallow marine sequences of the northern South China Sea (SCS) are uplifted and exposed by plate convergence in the Taiwan mountain belt. These deposits provide detailed geological information about the rifting event, stratigraphy, sedimentology, paleoclimate and paleoceanography of the shallow SCS to compare with what are recorded in the ODP 1148 deep-sea core. Seismic surveys and marine micropalentological studies show that Eocene sequences in the offshore Taiwan Strait and onland Taiwan mountain belt are all deposited in rifting basins and are covered unconformably by the Late Oligocene-Neogene post-rifting strata. Between syn-rifting and post-rifting sequences, there is a regional break-up unconformity throughout the island. Early Oligocene and Late Eocene strata are missing along the break-up unconformity equivalent to the T7 unconformity in the Pearl River Mouth Basin off south China. This may suggest that the SCS oceanic crust could have initiated between 33 and 39 Ma. Neither obvious stratigraphic gap nor slumping features are found in the Oligocene-Miocene transition interval of Taiwan. This observation highly contrasts with what has been documented from the ODP 1148 deep-sea core. This suggests that the stratigraphic gap and slumping features could only be recorded in the SCS deep sea region, but not in the shallow shelf near Taiwan. Compared to the Middle Miocene paleoceanographic re-organization events in the SCS deep sea, the geological history of the Taiwan shallow sequence shows changes of in sedimentation and faunal composition. Due to the Antarctic glacial expansion at~14 Ma, Middle to late Miocene strata of the Western Foothills show progressive regression sedimentations associated with a decrease of benthic foraminif-eral abundance and a sharp faunal turnover event. Many Early-Middle Miocene endemic benthic foraminifers were extinct in 14-13 Ma and new benthic foraminifers of the Kuroshio Current fauna appeared from 10.2 Ma, comparable with new occurrence of Modern benthic foraminifers at 9 Ma in the Java Sea area. This reveals that the Western Boundary Kuroshio Current in the North Pacific could initiate from 10-9 Ma due to closures of the Indo-Pacific seaways by convergent tectonics between the Australian Continent and the Indonesian Arc in 12-8 Ma. Subduction of the SCS oceanic lithosphere since the Middle Miocene resulted in formation of the Hengchun Ridge accretionary prism and the North Luzon Arc. Occurrence of these two bathymetric highs ( 2400 m) since the Middle Miocene and closures of the inter-arc passages in the North Luzon arc in the last 3.5 Ma would control the water exchanges between the West Pacific and the deep SCS. Accordingly, the tectonic evolution in the Central Range-Hengchun Peninsula accretionary prism and the arc-forearc Coastal Range not only control directly the route for water exchanges between the West Pacific and the SCS, but also indirectly shows a great influence on the geochemistry of deep SCS waters. The latter is best shown by much negative carbon isotope values of benthic foraminifers in the ODP 1148 deep-sea core than the West Pacific records in the last 14 Ma.     

海金沙孢子体快速繁殖体系的建立

以海金沙孢子叶为材料进行了繁殖研究,得出孢子叶分化为GGB的最佳条件为MS+NAA 0.3mg/L+6-BA0.5 mg/L,诱导率达90%;GGB增殖分化形成幼苗的最佳条件为MS+6-BA1.5mg/+NaH₂PO₄200mg/L,增值系数达7.8;生根培养基最佳条件为1/2 MS+NAA 0.1 mg/L+2%蔗糖,生根率达86.7%或者是1/2 MS+IBA0.2 mg/L+2%蔗糖生根率为87%;炼苗移栽到珍珠岩:草炭=2:1的基质中,成活率达87.5%.能在短期内生产出大量海金沙组培苗,为工厂化育苗提供依据.     

含氧、氮席夫碱-3d-金属配合物的研究(Ⅰ)——2,4-二羟基苯甲醛-缩氨基脲及其铜(Ⅱ)的金属配合物的合成与表征

本文报导了2,4—二羟基苯甲醛——缩氨基脲及其铜的金属配合物。它的化学组成由元素分析和红外光谱表征。     

双回路非接触式温度传感器的研制

在研制双回路非接触式温度传感器的过程中,出现了许多问题,例如:信号间的耦合和隔离、噪声干扰以及机械误差的影响等等。本文对这些问题进行了分析并给出了具体的结构图和多组数据。这样通过适当的调试和数据处理,这些传感器便能对信号进行有效的耦合,对噪声进行有效的抑制,从而保证传感器在工业实际中得以正常应用。     

Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site

The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind. Regolith (unconsolidated surface material) at the Mars Exploration Rover Opportunity's landing site has been affected greatly by wind, which has created and reoriented bedforms, sorted grains, and eroded bedrock. Aeolian features here preserve a unique record of changing wind direction and wind strength. Here we present an in situ examination of a martian bright wind streak, which provides evidence consistent with a previously proposed formational model for such features. We also show that a widely used criterion for distinguishing between aeolian saltation- and suspension-dominated grain behaviour is different on Mars, and that estimated wind friction speeds between 2 and 3 m s(-1), most recently from the northwest, are associated with recent global dust storms, providing ground truth for climate model predictions.     

双—N(2-羟基乙基)β-雷锁醛亚胺合镍(Ⅱ)、铜(Ⅱ)的合成及其抗癌活性的研究

本文报导了双—N(2—羟基乙基)β—雷锁醛亚胺合镍(Ⅱ)和双—N(2—羟基乙基)β—雷锁醛亚胺合铜(Ⅱ)的合成,它们的组成已由元素分析和红外光谱所证实。抗癌活性试验表明,双—N(2—羟基乙基)β—雷锁醛亚胺合镍(Ⅱ)对肿瘤模型S_(180)(A)及艾氏腹水癌均有较好的抑制作用.     

Bioleaching of zinc from gold ores using Acidithiobacillus ferrooxidans

The present work investigated microbial leaching of zinc from ore using Acidithiobacillus ferrooxidans (ATCC 14859). The ore samples, consisted of 13wt% zinc, were obtained from a gold mine in north-eastern Thailand. A shake flask study was performed on the ore samples using a rotary shaker under the following fixed conditions (250 r·min⁻¹, 30°C for 16 d). The influence of various conditions, namely medium type (with and without iron), particle ore size (<20, 20-40, 40-60, 60-100, and >100 mesh), ore density (20 kg·m⁻³, 50 kg·m⁻³, and 100 kg·m⁻³), and pH of the medium (2, 2.5, 2.8, and 3), were investigated. The microbial leaching was assessed by determining the concentration of zinc in the medium and compared with the initial sample concentration. The results show that Acidithiobacillus ferrooxidans can successfully leach zinc by as much as 6 times compared with the control experiment (without Acidithiobacillus ferrooxidans ferrooxidans). The maximum efficiency (92.3%) for microbial leaching is obtained in iron-containing medium, 20-40 mesh ore sizes, 20 kg·m⁻³ ore density at pH 2.8, and the zinc content is found in the medium at about 120 mg·L⁻¹.     

Replacement of huntingtin exon 1 by trans-splicing

Huntington’s disease (HD) is an autosomal-dominant neurodegenerative disorder caused by polyglutamine expansion in the amino-terminus of huntingtin (HTT). HD offers unique opportunities for promising RNA-based therapeutic approaches aimed at reducing mutant HTT expression, since the HD mutation is considered to be a “gain-of-function” mutation. Allele-specific strategies that preserve expression from the wild-type allele and reduce the levels of mutant protein would be of particular interest. Here, we have conducted proof-of-concept studies to demonstrate that spliceosome-mediated trans-splicing is a viable molecular strategy to specifically repair the HTT allele. We employed a dual plasmid transfection system consisting of a pre-mRNA trans-splicing module (PTM) containing HTT exon 1 and a HTT minigene to demonstrate that HTT exon 1 can be replaced in trans. We detected the presence of the trans-spliced RNA in which PTM exon 1 was correctly joined to minigene exons 2 and 3. Furthermore, exon 1 from the PTM was trans-spliced to the endogenous HTT pre-mRNA in cultured cells as well as disease-relevant models, including HD patient fibroblasts and primary neurons from a previously described HD mouse model. These results suggest that the repeat expansion of HTT can be repaired successfully not only in the context of synthetic minigenes but also within the context of HD neurons. Therefore, pre-mRNA trans-splicing may be a promising approach for the treatment of HD and other dominant genetic disorders.