从蚕的生命到艺术：中国古代生命观的哲学表达

中国考古出土的蚕业实物及蚕的艺术形象比较丰富,蚕的艺术形象如蚕纹、陶蚕蛹、牙雕蚕、玉石蚕、铜蚕、金蚕等,可统称为"蚕的模拟形态"。对蚕的模拟形态的功用,已有的诸多解释都有待完善。研究表明,蚕的模拟形态或艺术形象表达的功用或为饰品,或为装饰图案,或有待进一步考究。但无论哪种功用,用"蚕"这一形象都蕴含了特有的用意。通过对中国古代生命观的考察,文章认为蚕的艺术形象折射出相应的中国古代哲学生命观,即中国古人追求的死而复生、生生不息、羽化成仙、长乐无极等观念。     

Irradiation-induced large bubble formation and grain growth in super nano-grained ceramic

In this work, 0.5TRPO•0.5Gd₂Zr₂O₇ ceramic with an average grain size of only ∼15 nm was prepared by a high pressure (5 GPa/520 °C) sintering method. Phase evolutions and microstructure changes of the as-fabricated super nano and micron-grained ceramics under a high-dose displacement damage induced by 300 keV Kr²⁺ ions were investigated. The results show that the super nano-grained ceramic has low degree of amorphization, obvious grain growth (2–3 times in grain size) and big Kr bubbles (10–68 nm) formation after irradiation. The micron-grained ceramic was severely amorphized after irradiation and many microcracks were formed parallel to its surface. The formation mechanism of Kr bubbles in the super nano-grained ceramic is on account of grain boundary diffusion and migration induced by the accumulation of the injecting Kr ions and irradiation defects. Nevertheless, microcracks formed in the micron-grained sample are caused by the accumulation of Kr atoms.     

Chemical durability and surface alteration of lanthanide zirconates (A2Zr2O7: A = La-Yb)

Chemical durability of lanthanide zirconates (A₂Zr₂O₇) (A = La-Yb) under near-field environments is important for evaluating their application as potential nuclear waste forms. In this work, A₂Zr₂O₇ (A = La-Yb) are synthesized by spark plasma sintering with controlled microstructure and their chemical durability are evaluated in a nitric acid solution (pH = 1). Scanning transmission electron microscopy analysis reveals an amorphous passivation film either enriched with Zr or lanthanide. The complex chemistry of the passivation films can be correlated with a transition in corrosion mechanisms from a preferential release of lanthanide in La₂Zr₂O₇ to a preferential release of Zr in Er₂Zr₂O₇ and Yb₂Zr₂O₇. These results suggest a dominant mechanism of incongruent dissolution and surface reorganization for the formation of passivation films. Strong correlations are identified between the leaching rates and cation ionic size, ionic potential, electronegativity differences between A-site cation and Zr, and bonding valence sum of oxygen, suggesting important impacts of structural and bonding characteristics in controlling chemical durability of lanthanide zirconates.     

Multiplane displays based on liquid crystals for AR applications

Multiplane displays are capable of displaying 3D scenes with correct focus cues by creating multilayer 2D images in the display volume. Hence, such a 3D display technique could effectively address the accommodation‐vergence conflict (AVC) problem, which is prevalent in augmented reality (AR) displays. In this paper, we review the recent progress on multiplane AR displays based on liquid crystals (LCs) for AR applications. The working principle of multiplane AR displays is illustrated, the electro‐optical properties of the tunable LC devices are investigated and display prototypes are demonstrated. Finally, we discuss the prospects and challenges of multiplane AR displays based on LCs.     

石灰石矿山台阶边坡爆破振速安全阈值研究

爆破是矿山露采的必要手段,爆破振速安全阈值的确定对矿山台阶边坡的安全开采起着重要的作用。以四川兴联石灰石矿山台阶边坡为例,采用速度判别法,选取规范中的爆破振速安全阈值为拟静力法和动力显示分析法作参考;采用拟静力法,选取优势结构面作为潜在滑动面反演得到爆破振速安全阈值;采用ANSYS/LS-DYNA的动力显示分析法,建立台阶边坡模型,选取模拟监测点数据与实际监测数据进行对比,并结合质点振动速度与应力进行回归分析得到爆破振速安全阈值。通过对三种方法的对比研究得到,拟静力法与动力显示分析法得到的结果接近,且符合速度判别法中的规范。综合三种分析方法最终对台阶边坡爆破振速安全阈值进行合理取值。     

微结构模芯的精密磨削及其在微注塑成形中应用

针对微结构聚合物元器件的批量化生产与制造效率低等问题，采用精密修整成V形尖端的金刚石砂轮，在自润滑性和脱模性良好的钛硅碳陶瓷模芯表面加工制造出形状精度可控的V沟槽阵列结构，然后利用微注塑成形工艺将模芯表面的V沟槽阵列结构一次成形复制到聚合物表面，高效注塑成形制造出倒V形阵列结构的聚合物工件。分析了微模芯的表面加工质量与形状精度，研究了熔体温度、注射速度、保压压力、保压时间等微注塑成形工艺参数对微结构聚合物注塑成形角度偏差和填充率的影响。实验结果表明：通过微细磨削加工技术和微注塑成形工艺可以高效率、高精度地制造出规则整齐的微结构注塑工件，注射速度对微成形角度偏差的影响最大，保压压力对微成形填充率的影响最大，微结构模芯的微细磨削形状精度值为4.05 μm，微成形的最小角度偏差和最大填充率分别为1.47°和99.30%。     

实物地质资料展览展示研究——以国土资源实物地质资料中心为例

为了让国家馆藏实物地质资料资源“看得见、可获取、用得起、盘得活”,服务于拥有不同需求的专业人员和社会公众用户群体,在展览展示内容、展示方法和结构上有所创新,经过深入、系统地科学研究,理清了实物地质资料展览展示的特色,准确把握和定位了展览大纲,使实物展品、辅助展品、展示方式与展厅所在建筑物融为一体,全面科学地落实和确定了实物地质资料展品和布展方案,创新了实物地质资料展览展示技术方法,提出了以国家馆藏实物地质资料为基础的典型实物展示与多媒体全面展示相结合、模块化展览设计的技术思路,为实物地质资料展览展示的进一步研究提供了技术储备。