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1.
Kyle L. Covington Alexander K. Goroncy Teresa E. Lehmann Zuhao Kou Heng Wang Vladimir Alvarado 《American Institute of Chemical Engineers》2021,67(2):e17074
Microtomography (μCT) and nuclear magnetic resonance (NMR) have been used to characterize porous media for decades. Magnetic resonance imaging (MRI) enables direct visualization of pore architecture and many pulse sequences exist. In this work, we tested the MRI pulse sequence Zero Echo Time (ZTE) to study sandstone and carbonate for its ability to address short relaxation times. We aimed at resolving two fluid conduit scales, that is, pores and fractures. In this research, we study tighter porous systems than those previously reported using ZTE. Additionally, pore cluster analysis (PCA), combined with ZTE, can be used to analyze pore-fracture connectivity of relatively large core plugs. We show that ZTE can resolve two-scale pore systems simultaneously, that is, fractures and pores. By combining time-domain NMR pore-size analysis and PCA, we show that careful selection of resolution is necessary to understand transport in porous media. 相似文献
2.
Ping Xiao Jue Wang Lei Fang Zitong Zhao Xiangshi Sun Xiaochen Liu Haiqiang Cao Pengcheng Zhang Dangge Wang Yaping Li 《Advanced functional materials》2021,31(36):2104068
Neoantigen vaccines and adoptive dendritic cell (DC) transfer are major clinical approaches to initiate personalized immunity in cancer patients. However, the immunization efficacy is largely limited by the in vivo trajectory including neoantigens’ access to resident DCs and DCs’ access to lymph nodes (LNs). Herein, an innovative strategy is proposed to improve personalized immunization through neoantigen-loaded nanovaccines synergized with adoptive DC transfer. It is found that it enables selective delivery of neoantigens to resident DCs and macrophages by coating cancer cell membranes onto neoantigen-loaded nanoparticles. In addition, the nanovaccines promote the secretion of chemokine C-C motif ligand 2 (CCL2), CCL3, and C-X-C motif ligand 10 from macrophages, thus potentiating the access of transferred DCs to LNs. This immunization strategy enables coordinated delivery of identified neoantigens and autologous tumor lysate-derived undefined antigens, leading to initiation of antitumor T cell immunity in a personalized manner. It significantly inhibits tumor growth in prophylactic and established mouse tumor models. The findings provide a new vision for potentiating adoptive cell transfer by nanovaccines, which may open the door to a transformative possibility for improving personalized immunization. 相似文献
3.
Terahertz (THz) imaging is expected to become powerful tools for non-destructive inspections. To ensure the practical use of THz non-destructive monitoring, versatile THz imagers with adjustable designs that can eliminate the complexities and the bulkiness of the device are urgently required. Herein, a self-aligned filtration process for a 2D, free-standing carbon nanotube film array and its application to a THz video camera patch are reported. The presented techniques enable a) to freely design the camera size, sensor array pattern, and suspended shape according to its applications, b) to cut the camera patch into desired shapes, and c) to attach them to the objects that are intended to be measured. Real-time, non-destructive monitoring of various infrastructures is demonstrated. These results indicate that it can function regardless of restrictions, such as the shapes and locations of the measurement samples, thus providing a strong possibility for use in future non-destructive sensor networks. 相似文献
4.
研究了面铣刀的主偏角对切屑厚度和每齿进给量的影响,铣削中每齿进给量的决定因素,切削宽度与刀具直径的比值对切屑厚度的影响等问题进行理论分析,同时结合变速箱壳体铣削加工过程进行验证,解决了合理选择铣刀及切削参数以提升加工效率的问题。 相似文献
5.
6.
丙烯醇是一种十分重要的中间体和化学原料。近年来,以甘油为原料直接制备丙烯醇的研究引起了许多科学家的关注。本文参考了最近十年来发表的文献,详细介绍了均相甲酸诱导的甘油脱氧脱水反应、催化剂作用下的甘油脱氧脱水反应、液固相甘油氢解反应和气固相甘油氢转移反应等过程制备丙烯醇的相关工艺、反应机理和催化剂的研究进展及发展趋势,并对比了上述工艺的优缺点。其中,均相甲酸诱导的甘油脱氧脱水工艺比较成熟,已经在实验室中得到验证和应用,但是甲酸的消耗量大,整个过程的原子经济性很差。 甘油脱氧脱水反应和液固相甘油氢解反应不仅需要采用价格昂贵的铼基催化剂,而且丙烯醇的选择性较低。 铁基催化剂作用下的气固相甘油氢转移反应制备丙烯醇,由于催化剂的价格低廉、制备工艺简单、产品分离容易等优势而备受关注,是最近五年的研究热点。在文献基础上,认为今后研究应该重点关注催化剂的酸碱性、氢转移能力及其与速率控制步骤的匹配,并有针对性地对催化剂进行优化和改进。 相似文献
7.
Shen Youqing Zhang Jing Guo Hongwei Liu Rongqiang Kou Ziming 《Journal of Mechanical Science and Technology》2021,35(5):2083-2095
Journal of Mechanical Science and Technology - Aiming at the problem that the membrane structure is prone to creases in the process of folding and compaction, a proxy model is used to replace the... 相似文献
8.
Xiaorui Gao Ximeng Liu Dajun Wu Bin Qian Zongkui Kou Zhenghui Pan Yajun Pang Linqing Miao John Wang 《Advanced functional materials》2019,29(36)
The Al effect on the electrochemical properties of layered double hydroxides (LDHs) is not properly probed, although it is demonstrated to notably promote the capacitive behavior of LDHs. Herein, ternary NiCo2Alx layered double hydroxides with varying levels of Al stoichiometry are purposely developed, grown directly on mechanically flexible and electrically conducting carbon cloth (CC@NiCo2Alx‐LDH). Al plays a significant role in determining the structure, morphology, and electrochemical behavior of NiCo2Alx‐LDHs. At an increasing level of Al in NiCo2Alx‐LDHs, there is a steady evolution from 1D nanowire to 2D nanosheets. The CC@NiCo2Al‐LDH at an appropriate level of Al and with the nanowire–nanosheet mixed morphology exhibits both significantly enhanced electrochemical performance and excellent structural stability, with about a 2.3‐fold capacitance of NiCo2‐OH. When applied as the anode in a flexible asymmetric supercapacitor (ASC), the CC@NiCo2Al‐LDH gives rise to a remarkable energy density of 44 Wh kg?1 at the power density of 462 W kg?1, together with remarkable cyclic stability with 91.2% capacitance retention over 15 000 charge–discharge cycles. The present study demonstrates a new pathway to significantly improve the electrochemical performance and stability of transition metal LDHs, which are otherwise unstable in structure and poorly performing in both rate and cycling capability. 相似文献
9.
由于缺乏有效的需求收集和管理方法、无法进行早期需求验证和需求变化演进等问题,核电设计产品越来越难满足用户期望。针对上述问题,本文以安注系统为例,将需求建模方法应用于需求分析:通过需求用例建模、需求场景建模和需求逻辑建模等手段实现安注系统的需求收集和管理,通过状态图的执行确保顶层设计满足用户需求,通过时序图的比较检查遗漏或不一致的需求等。借助需求建模实现需求的早期验证,确保设计产品符合用户需求,为需求建模在核电设计中的进一步应用提供参考。 相似文献