3-D velocity structure in the central-eastern part of Qilianshan

The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters.

3-D velocity structure in the central-eastern part of Qilianshan

The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters.

3D微纳米打印技术与应用研究进展

近年来3D微纳米打印技术发展迅速,尤其是在微纳米结构成型方面有着独特的优势。重点讲述了微立体光刻(MSLA)、微激光烧结(MSLS)、熔融沉积造型(FDM)、片材层压(LOM)、双光子聚合(TPP)、直写成型技术(DIW)的基本结构原理和国内外研究现状,对不同3D微纳米打印技术进行了对比分析,详细阐述了3D微纳米打印在生物医疗、组织工程和微流控芯片的应用,并展望了3D微纳米打印的应用前景。

Static dissolution-induced 3D pore network modification and its impact on critical pore attributes of carbonate rocks

To determine the effect of dissolution on pore network development in carbonate rocks, dissolution experiments, X-Ray microtomography, and thin section analysis were conducted on argillaceous limestone and grain limestone samples at different temperatures and constant pH, HCl concentration. The relationship between Ca^(2+) concentration and time was revealed through the experiments; pore size distribution before and after dissolution indicate that there is no correlation between the temperature and pore size variation, but pore size variation in grain limestone is more significant, indicating that the variation is mainly controlled by the heterogeneity of the rock itself(initial porosity and permeability) and the abundance of unstable minerals(related to crystal shape, size and mineral type). At different temperatures, the two kinds of carbonate rocks had very small variation in pore throat radius from 0.003 mm to 0.040 mm, which is 1.3 to 3.5 times more, 1.7 on average of the original pore throat radius. Their pore throat length varied from 0.05 mm to 0.35 mm. The minor changes in the pore throat radius, length and connectivity brought big changes to permeability of up to 1 000×10^(-3) μm^2.

Research of micro-EDM and its applications

A Micro Electrical Discharge Machining (MEDM) equipment was developed in this paper,on which the CNC interpolation for 3-axis linkage movement could be realized easily. By this micro-EDM equipment,the fabrication process of microelectrode,micro hole,silicon wafer and complex microstructure was discussed. The process rules of machining efficiency and the relative electrode wear rate as well as the machining mechanism and performance of silicon micro-EDM were also researched. Machining experiments showed that the microelectrode diameter as small as 6 μm and the micro hole with minimum size of 10 μm could be obtained steadily,and the maximum aspect ratios of microelectrode and micro hole were over 25 and 10 respectively. And silicon micro-EDM experiments showed that the micro beam with the aspect ratios over 15 could be obtained easily. And a micro beam with minimum size of 23 μm width on a silicon wafer with 420 μm thickness was achieved. At last,the microstructure machining technology for micro-EDM was also discussed. And a micro-facial sculpture with free space curved surface and size of 1 mm×0.3 mm×0.18 mm was also machined successfully.

Ti_(3)C_(2)T_(x)基复合电磁吸波材料的研究进展

随着电磁污染日益严重,新型吸波材料的研发需求日益高涨。在下一代吸波材料的候选者中,碳化钛(Ti_(3)C_(2)T_(x))材料以其卓越的导电性、丰富的表面极性官能团、易于调整的电磁参数、低密度、良好的机械性能和易于加工等优势脱颖而出,受到了广泛的关注。为此,介绍了Ti_(3)C_(2)T_(x)材料的独特性质和其在吸波领域的潜力,并详细探讨了Ti_(3)C_(2)T_(x)作为吸波材料的优势和研究进展,以及不同微纳结构对吸波性能的影响。最后,综述了Ti_(3)C_(2)T_(x)复合材料在电磁波吸收领域仍然面临的一些问题及发展趋势,为高性能吸波材料的设计和制备提供了重要参考。

CPE包覆纳米CaCO_3对PVC/纳米CaCO_3复合材料结构与性能的影响

研究了基体韧性、纳米CaCO3直接填充与用CPE包覆后填充PVC对复合材料力学性能的影响 ,并对其微观结构进行了探讨。结果表明 ,适当的基体韧性有助于获得较高的冲击强度 ;两种填充方法下 ,PVC复合材料的冲击强度和拉伸强度呈现出不同的变化趋势。包覆处理填充体系的冲击强度均要比未包覆处理填充体系的略低 ,而拉伸强度则相反 ,特别是在包覆小份量CaCO3( 2份 )时 ,所得复合材料的冲击强度甚至比PVC/CPE( 8份 )基体的低12 % ,而拉伸强度则出现最大值 ,比基体的高 8

The Characteristics of Putaohua Reservoir and Development Strategies in Xujiaweizi Baxin Oilfield

With the using of new full 3 - D interpretative technology, the carefully interpretation of the micro - amplitude structures and faults by the reprocessed 3 -D seismic data in IES (Interactive Exploration System) interpretative system of Sun workstation is obtained. Because of the application of the well - advanced predictive technique for reservoir lithological changes, the predictive accuracy rate of drilling for 31 wells drilled in 1996 achieved 100 % and the economic and social benefits are desirable.

Study on the micro-region structure and properties of two dithienothiophene-dicarboxylic acids

Self-organized dithieno [3,2-b:2',3'-d] thiophene-2,5-dicarboxylic acid (A) and dithieno [2,3-b:3',2'-d] thiophene-2,5-dicarboxylic acid (B) films were prepared through solvent-induced order-disorder transition method.The arrangement of the two molecules on substrates were observed by atomic force microscopy (AFM),which demonstrated that A was arranged orderly in a certain angle on mica,while B was flat-flying on mica.The optical and conductance properties in micro region of these two compound films were characterized by UV-vis absorption spectroscopy,fluorescence spectroscopy and conductive atomic force microscopy (C-AFM).The results revealed that the fluorescence and absorption peaks of A had a large red shift in comparison with those of B.The conductance of the J-aggregates for A is three orders magnitude higher than that of B.It is concluded that the large conductance difference mainly comes from different aggregation structures and orientations of these two molecules on substrate.

Bridging the structure gap between pellets in artificial dissolution media and in gastro-intestinal tract in rats

Changes in structure of oral solid dosage forms(OSDF) elementally determine the drug release and its therapeutic effects.In this research,synchrotron radiation X-ray micro-computed tomography was utilized to visualize the 3 D structure of enteric coated pellets recovered from the gastrointestinal tract of rats.The structures of pellets in solid state and in vitro compendium media were measured.Pellets in vivo underwent morphological and structural changes which differed significantly from those in vitro compendium media.Thus,optimizations of the dissolution media were performed to mimic the appropriate in vivo conditions by introducing pepsin and glass microspheres in media.The sphericity,pellet volume,pore volume and porosity of the in vivo esomeprazole magnesium pellets in stomach for2 h were recorded 0.47,1.55 × 10^(8)μm^(3),0.44 × 10^(8)μm^(3)and 27.6%,respectively.After adding pepsin and glass microspheres,the above parameters in vitro reached to 0.44,1.64 × 10^(8)μm^(3)0.38 × 10^(8)μm^(3)and 23.0%,respectively.Omeprazole magnesium pellets behaved similarly.The structural features of pellets between in vitro media and in vivo condition were bridged successfully in terms of 3 D structures to ensure better design,characterization and quality control of advanced OSDF.

用于微结构探测的并行共焦光学结构的研究

基于菲涅尔衍射理论推导并行共聚焦系统的两种常用光路(显微与远心)的三维相干成像公式,发现两者在傍轴近似条件下并行探测能力没有明显区别,并且这一结果得到了实验证实。但是显微光路离轴探测光场在物面和图像面存在横向漂移,漂移随着离轴和离焦程度增加而增加,干扰了系统的轴向探测能力并且使正焦辨识过程复杂化,影响系统的测量效率;远心光路由于不存在探测光场的横向漂移,以及较好的结构可靠性使系统精度易于保证,应该成为构建并行共聚焦微结构探测系统的首选。

圆织三维管状碳纤维复合材料弹性性能预测

为给圆织复合材料的工程应用提供参考依据,建立适当的单元胞体力学模型来预测其工程弹性常数。该模型采用跑道型纤维束截面假设,基于可设计几何参数和单元胞体的组织结构,合理预测了圆织三维管状复合材料纤维体积分数和弹性常数。并采用有限元方法对该模型进行了拉伸载荷下的力学分析,合理确定了复合材料的应力分布。结果表明,采用有限元方法所得的预测值与理论计算数值具有很好的一致性,证明了细观几何模型以及弹性常数分析方法的正确性。

基于同步辐射光刻的三维微细加工方法

同步辐射光刻的三维聚甲基丙烯酸甲酯(Polymethyl Methacrylate,PMMA)微结构制造对X射线光刻掩膜板的吸收体形状和PMMA所吸收的X射线能量分布有直接影响,即三维PMMA微结构形状取决于X射线光刻掩膜板的吸收体形状。如果不对X射线光刻掩膜板进行补偿,在被曝光的结构中可观察到结构侧面的变形。研究了引起这种结构侧面变形的各种原因并提出X射线剂量对刻蚀深度非线性曲线是最直接的原因。基于X射线光刻掩膜板图形形状和实际制造的三维PMMA微结构的误差,X射线光刻掩膜板从双直角三角形变为双半圆图形使得微注射针阵列的强度得到增强。为了量化实际制造的三维PMMA微结构的误差,给出了X射线吸收能量分布与微结构的结构形状数据。

高压碳化法可控制备微纳米分级结构中空棒状碳酸钙及其表征

以氢氧化钙为钙源,D-葡萄糖酸钠为添加剂,在高压碳化釜中采用二氧化碳鼓泡碳化法制备出分散均匀,由立方状纳米粒子组装而成具有微纳米分级结构的中空棒状碳酸钙聚集体。探究了各因素对高压碳化法制备碳酸钙的影响,通过改变反应温度、D-葡萄糖酸钠的添加量、氢氧化钙的浓度等考察制备的最佳条件。采用SEM、TEM、XRD、FTIR和BET等测试手段对产品的结构和性能进行了表征。实验结果表明,所制备的微纳米分级结构中空棒状碳酸钙的平均直径约300nm,长度为1~2μm,壳壁由粒径为50~100nm的纳米立方状粒子聚集而成,壳层厚度约100nm。同时,在反应温度为120℃、氢氧化钙质量分数为2%、D-葡萄糖酸钠添加量为氢氧化钙质量的2%、反应时间为4h的条件下,所制备的中空棒状碳酸钙的分散性和均匀性最好。

三维石墨烯的制备及其影响因素

采用绿色还原剂L-抗坏血酸还原氧化石墨烯(GO),在常压、较低的温度下快速制备三维石墨烯。通过对反应物GO质量浓度和还原剂质量的比较以及对反应过程的实时监控,发现二者与三维石墨烯的形成密切相关。当GO质量浓度和L-抗坏血酸的质量浓度较低时,由于反应速率慢导致石墨烯无法形成稳定的三维结构。只有增大GO质量浓度和L-抗坏血酸的质量浓度、加快反应速率才能形成三维微孔结构石墨烯。通过冷冻干燥形成的石墨烯气凝胶具有优异的机械强度。比较SEM图可知,GO的质量浓度与三维石墨烯的内部形貌存在一定关联,可以通过控制GO质量浓度以及L-抗坏血酸的量制备不同形貌的三维石墨烯。

三维纳米结构氧化锌的制备

采用两步溶液法在硅片表面制备了新颖的三维纳米结构氧化锌,并采用SEM和XRD等手段对其进行了表征.两步溶液法制备实验表明:当氧化锌种子层的生长制备时间在48 h、种子层外延生长时间超过7 h,在硅片表面就能得到三维纳米结构氧化锌.对三维纳米结构氧化锌的生长机理进行了初步探究.

Synthesis of 3D printing materials and their electrochemical applications

Three-dimensional(3 D)printing,also known as additive manufacturing,has the advantages of low cost,easy structure operation,rapid prototyping,and easy customization.In the past few years,materials with different structures,compositions,and properties have been widely studied as prospects in the field of 3 D printing.This paper reviews the synthesis methods and morphologies of one-,two-and threedimensional micro/nano materials and their composites,as well as their applications in electrochemistry,such as supercapacitors,batteries and electrocatalysis.The latest progress and breakthroughs in the synthesis and application of different structural materials in 3 D-printing materials,as well as the challenges and prospects of electrochemical applications,are discussed.

Fabrication and multiscale characterization of 3D silver containing bioactive glass-ceramic scaffolds

In this work,we fabricated and characterized bioactive 3D glass-ceramic scaffolds with inherent antibacterial properties.The sol-gel(solution-gelation)technique and the sacrificial template method were applied for the fabrication of 3D highly porous scaffolds in the 58.6SiO2-24.9CaO-7.2P2O5-4.2Al2O3–1.5Na2O−1.5K2O–2.1Ag2O system(Ag-BG).This system is known for its advanced bioactive and antibacterial properties.The fabrication of 3D scaffolds has potential applications that impact tissue engineering.The study of the developed scaffolds from macro-characteristics to nano-,revealed a strong correlation between the macroscale properties such as antibacterial action,bioactivity with the microstructural characteristics such as elemental analysis,crystallinity.Elemental homogeneity,morphological,and microstructural characteristics of the scaffolds were studied by scanning electron microscopy associated with energy dispersive spectroscopy(SEM-EDS),transmittance electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR),and UV-visible spectroscopy methods.The compressive strength of the 3D scaffolds was measured within the range of values for glass-ceramic scaffolds with similar compositions,porosity,and pore size.The capability of the scaffolds to form an apatite-like phase was tested by immersing the scaffolds in simulated body fluid(SBF)and the antibacterial response against methicillin-resistant Staphylococcus aureus(MRSA)was studied.The formation of an apatite phase was observed after two weeks of immersion in SBF and the anti-MRSA effect occurs after both direct and indirect exposure.

花岗岩残积土颗粒及水分形态三维微观结构

采用高分辨率X射线计算机断层扫描技术(X-rayμ-CT)对花岗岩残积土三维微观结构进行重构并在以下方面取得新进展:(1)通过在试样液相中添加显影物质(CsCl),成功获取土中水分形态及空间分布;(2)利用X射线在不同物质中的衰减率差异,进一步区分固体颗粒中高岭石与石英并确定各自空间分布;(3)通过三维重构图像,对颗粒空间接触关系进行初步概化与分类,同时对X射线计算机断层扫描技术在非饱和土力学中的进一步应用做了前瞻。这些初步探索将有助于对土体三维真实结构的全面认识,促进计算机断层扫描技术在岩土/地质工程领域的新开拓。

Imaging/nonimaging microoptical elements and stereoscopic systems based on femtosecond laser direct writing

The development of modern information technology has led to significant demand for microoptical elements with complex surface profiles and nanoscale surface roughness.Therefore,various micro-and nanoprocessing techniques are used to fabricate microoptical elements and systems.Femtosecond laser direct writing(FsLDW)uses ultrafast pulses and the ultraintense instantaneous energy of a femtosecond laser for micro-nano fabrication.FsLDW exhibits various excellent properties,including nonlinear multiphoton absorption,high-precision processing beyond the diffraction limit,and the universality of processable materials,demonstrating its unique advantages and potential applications in three-dimensional(3D)micro-nano manufacturing.FsLDW has demonstrated its value in the fabrication of various microoptical systems.This study details three typical principles of FsLDW,several design considerations to improve processing performance,processable materials,imaging/nonimaging microoptical elements,and their stereoscopic systems.Finally,a summary and perspective on the future research directions for FsLDW-enabled microoptical elements and stereoscopic systems are provided.