科创中国

由隆巽教授率领的日本东京技术研究院在进行了为期5年的研究后于2012年3月20日宣布开发成功可提高产率、减少焦炭生成和延长催化剂寿命的石脑油裂解工艺.

介绍了纳米压痕测试技术的基础理论及纳米压痕法常用的Oliver-Pharr方法的计算原理.采用纳米压痕试验测得不同表面粗糙度的Li2O-Al2O3-SiO2微晶玻璃样品的纳米硬度、弹性模量和载荷一位移曲线.结果表明样品表面粗糙度会降低纳米压痕测试结果的稳定性、准确性和可靠性:样品表面粗糙度越小,测得的纳米硬度和弹性模量值波动越小,载荷-位移曲线重合性越高.随着最大载荷的增大,测得的弹性模量逐渐减小,其原因是压痕边缘材料发生了塑形变形.在超光滑表面样品(Ra=0.9 nm)上测得较为准确的Li2O-Al2O3-SiO2微晶玻璃纳米硬度和弹性模量值分别为8.8 GPa和7.79 GPa.纳米压痕测试结果的重合度对于评价超光滑表面完整性研究具有指导意义.

综述了纳米复合食品包装材料中纳米成分检测与迁移的国内外研究进展,重点就纳米复合包装材料中纳米成分检测的前处理方法、形貌检测和含量检测方法以及迁移研究进展进行了总结,为进一步的理论和实验研究提供参考.

工业用线钳表面抛光机床是一种新型的磨削装置,其磨削过程用液压系统控制,从而实现大批量加工.该文首先利用三维设计软件UG NX3进行液压系统结构设计,再从结构方案的确定、主要部件的设计计算以及系统原理图的确定等几个方面对工业用线钳表面抛光机床液压系统进行了详细的分析,确保其性能良好.实验和应用证明:该液压系统运转平稳,稳定性和调节性能较好且密封可靠,使用效果良好.

常规油气资源的勘探开发已经步履艰难,以纳米油气为主体的非常规油气资源潜力巨大,即将成为石油勘探开发的主要领域。然而,由于纳米油气与常规油气的特征差异巨大,指导常规油气勘探开发的传统石油地质学不适用于非常规油气资源的勘探开发。纳米石油地质学是纳米科技与石油地质学之间的交叉学科,它伴随着非常规油气资源勘探开发的迫切需要、纳米科技的迅速发展而诞生,以纳米油气的生成、滞留、运移、聚(富)集、赋存、散失的机理和分布规律为主要研究内容,以非常规油气形成、产出状态和分布特征为研究目标。纳米科技理念及其高分辨分析测试技术、物理模拟实验、典型实例剖析是纳米石油地质学的主要指导思想和研究手段。纳米石油地质学将是一门全新的石油地质理论体系,在未来的油气勘探开发中将发挥重要的指导作用。

利用柠檬酸溶胶-凝胶法成功合成了锌离子掺杂DyCoO3纳米材料,经粉末X射线衍射(XRD)和扫描电镜( SEM)表征后发现,所得掺杂Dy0.9 Zn0.1CoO3-δ纳米材料为纯相的正交钙钛矿结构,其尺寸约为30~150nm.将改性前后的DyCoO3纳米材料分别制作成电子元件并对其电性能对比研究,结果发现,锌离子的掺杂可以明显降低DyCoO3纳米材料的电阻,为其将来的应用提供了一条新颖的途径.

Life-history theory predicts that in hibemators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics: "active" males (adults only) emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than "passive" males (both yearling and adult). Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.

日本某公司从1960年开始潜心研究PA透明树脂,相继成功研发高透明、低吸水性、尺寸稳定性的TR55和TR90树脂并推向市场.

Models of optimal escape strategy predict that animals should move away when the costs of fleeing (metabolic and opportunity costs) are outweighed by the costs of remaining. These theoretical models predict that more vulnerable individuals should be more reactive, moving away when an approaching threat is further away. We tested whether escape behaviour (includ- ing 'escape calling') ofLithobates sphenocephalus approached by a human was influenced by body size or the initial microhabi- tat that the individual was found in. Irrespective of their size, frogs in the open tended to remain immobile, enhancing their cryp- sis. Frogs in cover showed different responses according to their body size, but, contrary to our initial predictions, larger frogs showed greater responsiveness (longer flight initiation distance and distances fled) than small frogs. Small frogs tended to remain closer to water and escaped into water, while larger individuals were more likely to jump to terrestrial cover and call during escape. Density of frogs near the focal animal had no effect on escape behaviour. This study indicates a range of escape responses in this species and points to the importance of divergent escape choices for organisms which live on the edge of different environments .

目的:构建一种向胰腺癌细胞安全、高效输送siRNA的免疫纳米载体。方法:检测纳米载体IONP-PEI(非靶向组)及其与siRNA复合物的表征;通过琼脂糖凝胶电泳检测siRNA结合力、MTS法检测细胞活力和流式细胞术检测转染率以确定其复合siRNA的最佳N/P比值;细胞免疫荧光和普鲁士蓝染色观察scFvCD44v6偶联IONP-PEI的靶向纳米载体(靶向组)在细胞内分布;流式细胞术、荧光显微镜观察、real-time PCR和Western blotting检测靶向组和非靶向组的转染率和转染siKRAS后的干扰效果。结果:IONP和PEI的最适质量比为0.75;纳米载体复合siRNA的最佳N/P比值为20;IONP-PEI/siRNA复合物的电位为(21.73±8.07) mV,粒径为(51.3±2.2) nm。荧光显微镜显示,非靶向组和靶向组转染后均在细胞内,靶向组的转染率为(89.75±1.81)%,高于非靶向组的(59.87±4.52)%,且靶向组的荧光强度高于非靶向组。靶向组的KRAS mRNA的相对表达量为(34.02±6.15)%,低于非靶向组的(51.09±6.70)%;Western blotting 显示靶向组的KRAS蛋白表达量低于非靶向组。结论:非靶向组和靶向组均能够将siRNA转染进细胞内,且靶向组具有更高的转染效率和更好的干扰基因表达效果。本课题构建的scFvCD44v6-IONP-PEI是一种高效、安全和靶向识别胰腺癌细胞的免疫纳米载体。