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41.
Molecular Ordering: Selectivity of Threefold Symmetry in Epitaxial Alignment of Liquid Crystal Molecules on Macroscale Single‐Crystal Graphene (Adv. Mater. 40/2018) 下载免费PDF全文
42.
Tunable Spectrum Selectivity for Multiphoton Absorption with Enhanced Visible Light Trapping in ZnO Nanorods 下载免费PDF全文
Kok Hong Tan Fang Sheng Lim Alfred Zhen Yang Toh Xia‐Xi Zheng Chang Fu Dee Burhanuddin Yeop Majlis Siang‐Piao Chai Wei Sea Chang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(20)
Observation of visible light trapping in zinc oxide (ZnO) nanorods (NRs) correlated to the optical and photoelectrochemical properties is reported. In this study, ZnO NR diameter and c‐axis length respond primarily at two different regions, UV and visible light, respectively. ZnO NR diameter exhibits UV absorption where large ZnO NR diameter area increases light absorption ability leading to high efficient electron–hole pair separation. On the other hand, ZnO NR c‐axis length has a dominant effect in visible light resulting from a multiphoton absorption mechanism due to light reflection and trapping behavior in the free space between adjacent ZnO NRs. Furthermore, oxygen vacancies and defects in ZnO NRs are associated with the broad visible emission band of different energy levels also highlighting the possibility of the multiphoton absorption mechanism. It is demonstrated that the minimum average of ZnO NR c‐axis length must satisfy the linear regression model of Z p,min = 6.31d to initiate the multiphoton absorption mechanism under visible light. This work indicates the broadening of absorption spectrum from UV to visible light region by incorporating a controllable diameter and c‐axis length on vertically aligned ZnO NRs, which is important in optimizing the design and functionality of electronic devices based on light absorption mechanism. 相似文献
43.
为了更加精确地研究压力型锚索的锚固机理,基于锚索预应力与岩土体蠕变的耦合效应推导了锚索预应力方程。在此基础上根据Mindlin问题解,推导了耦合效应作用下锚索砂浆体的压应力和剪应力近似解,并考虑锚索预应力与岩土体蠕变之间的耦合效应进行了案例分析。研究结果表明:锚索预应力和砂浆体受到的应力峰值均按反幂函数随时间逐渐衰减并稳定;承压板的长宽比与压应力峰值之间存在正相关关系,与剪应力峰值之间存在负相关关系;岩土体的泊松比与应力峰值之间存在正相关关系。该成果丰富了压力型锚索锚固机理的理论研究,可为边坡锚固设计提供一定的理论依据。 相似文献
44.
45.
Jie Hong Chiang Allan K. Hardacre Michael E. Parker 《International Journal of Food Science & Technology》2020,55(2):649-659
This study investigated the effects of moisture content (MC) on the physicochemical properties of extruded meat alternatives made from Maillard-reacted beef bone hydrolysate and plant proteins. Samples were extruded at 170 °C (maximum barrel temperature), at 3.6 kg h−1 (liquid feed rate) and at 1.8, 2.2, 2.6 and 3.0 kg h−1 (dry feed rates) to obtain MC of 60%MC, 56%MC, 52%MC and 49%MC, respectively. Meat alternatives at 52%MC showed the greatest degree of texturisation. However, meat alternatives at 49%MC were the closest in terms of both textural and microstructural properties to reference sample, boiled chicken breast. Results from protein solubility suggested that a large amount of aggregated proteins were associated with hydrogen bonds, while disulphide bonds were the main contributor in the formation of fibrous structure in meat alternatives. Results showed that the change in MC as process parameter played an important role in the formation of fibrous structure in extruded meat alternatives. 相似文献
46.
着陆缓冲机构是着陆器实现行星探测软着陆的关键部位之一,它的缓冲性能直接关系到着陆器是否能安全地在行星表面实现软着陆。根据某院提供的火星着陆器模型,在三维建模软件中建立着陆器的合理简化模型,为了提高分析着陆器软着陆过程冲击响应的准确性,采用MSC公司的Patran/Dytran有限元软件,用瞬态动力学的方法对着陆器的缓冲性能进行分析。仿真结果与试验数据十分吻合,着陆器的缓冲和传力性能良好。因此,采用拉杆缓冲的桁架式火星着陆器是可行的,仿真结果与试验数据也为今后的火星探测提供了参考。 相似文献
47.
48.
Preoperative chemoradiation therapy (CRT) is becoming the standard treatment for patients with locally
advanced rectal cancer. However, individual differences in response to treatment range from a complete response to
complete resistance. Predicting the tumor response to radiotherapy may improve the efficacy of radiotherapy. This
review mainly summarizes recent studies about the molecular biomarkers that can predict the response to
radiotherapy in rectal cancer. These studies have indicated that the molecular markers involved in the response to
radiotherapy mainly include genes related to radiosensitivity, cancer stem cell-related markers, non-coding RNAs
(ncRNAs), single-nucleotide polymorphisms (SNPs) and gene methylation, and other factors including
carcinoembryonic antigen (CEA) level, anemia, lymphocytes, and signaling pathways. Many of these identified
markers are mainly associated with DNA repair, apoptosis, and cell cycle, but some involve unknown cell
mechanisms. We speculate that predictors of radiotherapy response may involve combinations of multiple molecular
biomarkers that may be useful for the development of individualized therapy for rectal cancer patients. 相似文献
49.
梅山铁矿针对井下20 t电力机车齿轮箱由于缺油造成其齿轮箱故障频发,影响设备正常生产运行的问题,通过改进加装自行设计制作的油位检测装置后,齿轮箱缺油时及时报警,保证了齿轮箱的良好润滑,保障了电力机车的可靠平稳运行。 相似文献
50.
硅负极具有高比容量的显著优势,其理论比容量(4 200 mA∙h/g)达到传统石墨负极的10倍以上,被认为是锂离子电池最有潜力的负极之一。然而,硅负极存在导电性较差、充放电过程中体积膨胀巨大等诸多问题,导致其循环性能较差,限制了大规模实际应用。本文提供了一种高性能硅负极的制备方法及应用,通过将硅负极分散在多级孔碳中,连同黏结剂聚丙烯腈涂覆在集流体上,再对极片进行热处理实现聚丙烯腈碳包覆,有效提高电极的整体导电性并能为巨大的体积变化提供空间,从而提升硅负极的大倍率性能和循环稳定性。 相似文献