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51.
Kun Yang Yachun Wang Penghui Lei Tiankai Yao Dong Zhao Jie Lian 《Journal of the European Ceramic Society》2021,41(12):6018-6028
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. 相似文献
52.
53.
当场地土存在较深厚的砂土、粉土时,普通预制桩由于受到压桩施工条件和承载力的限制而不适用.文章通过对各种桩型的单桩承载力计算、施工可行性、经济性等多方面比对,提出刚性复合桩为优选方案,并通过实际工程案例,对刚性复合桩的设计和施工要点等方面进行了应用分析. 相似文献
54.
针对热液白云岩展布非均质性强的问题,开展基底断裂与茅三段沉积演化关系研究,分析断裂样式与白云岩分布关系,建立沉积演化模式,预测白云岩的分布。研究结果表明:茅三段可划分为5个小层,1~3小层为白云岩发育主要时期,4~5小层为台地均一化时期,不发育白云岩;15-1、15-2和16号基底断裂控制了早期“台-洼”相间的沉积地貌,断裂附近的地貌高部位为生屑滩发育有利部位,为白云岩的发育提供物质基础;15-1、15-2号基底断裂样式为花状,周边生屑滩白云石化程度高,为白云岩发育最有利区;16号基底断裂为直立状,附近白云石化发育程度较低,为白云岩发育较有利区。研究成果可为热液白云岩领域的进一步勘探提供指导依据。 相似文献
55.
锌的可充电电池有良好的电化学性能,但锌枝晶的问题会导致其库伦效率降低,发生短路,甚至形成"死锌".利用沉淀法制备新型复合材料ZnSO4·3Zn(OH)2·H2O@石墨烯作为电池的负极,使用2 mol/L K2SO4作为电解液,利用沉淀-溶解机制以达到实现抑制锌枝晶的目的.采用X线衍射仪(XRD)对循环前后的负极材料进行表征,用电子扫描显微镜(SEM)观察其形貌,结果表明,制备的新型负极材料在2 mol/L K2SO4电解液中能够完成1000次全放电/充电循环,库伦效率接近100%,容量保持80%,可以有效抑制锌枝晶,以实现电池的长循环稳定性. 相似文献
56.
Flexible solar cells are important photovoltaics (PV) technologies due to the reduced processing temperature,less ma-terial consumption and mechanical flexibility,thus they have promising applications for portable devices and building-integ-rated applications.However,the efficient harvesting of photons is the core hindrance towards efficient,flexible PV.Light man-agement by nanostructures and nanomaterials has opened new pathways for sufficient solar energy harvesting.Nanostruc-tures on top surfaces provide an efficient pathway for the propagation of light.Aside from suppressing incident light reflection,micro-structured back-reflectors reduce transmission via multiple reflections.Nanostructures themselves can be the absorber lay-er.Photovoltaics based on high-crystallinity nanostructured light absorbers demonstrate enhanced power conversion effi-ciency (PCE) and excellent mechanical flexibility.To acquire a deep understanding of the impacts of nanostructures,herein,a concise overview of the recent development in the design and application of nanostructures and nanomaterials for photovolta-ics is summarized. 相似文献
57.
Le Fang Qian Sun Yong-Hong Duan Jing Zhai Dan Wang Jie-Xin Wang 《Frontiers of Chemical Science and Engineering》2021,15(4):902
BaSO4 nanoparticles as important functional materials have attracted considerable research interests, due to their X-rays barrier and absorption properties. However, most of BaSO4 nanoparticles prepared by traditional technology are nanopowders with broad size distribution and poor dispersibility, which may greatly limit their applications. To the best of our knowledge, the synthesis of transparent BaSO4 nanodispersions was rarely reported. Here, we firstly present a novel and efficient method to prepare transparent and stable BaSO4 nanodispersions with a relatively small particle size around 10 to 17 nm using a precipitation method in a rotating packed bed (RPB), followed by a modification treatment using stearic acid. Compared with the BaSO4 prepared in a traditional stirred tank, the product prepared using an RPB has much smaller particle size and narrower size distribution. More importantly, by using RPB, the reaction time can be significantly decreased from 20 min to 18 s. Furthermore, the transparent BaSO4-polyvinyl butyral nanocomposite films with good X-ray shielding performance can be easily fabricated. We believe that the stable BaSO4 nanodispersions may have a wide range of applications for transparent composite materials and coatings with X-ray shielding performance for future research. 相似文献
58.
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
59.
Mekrattanachai Pagasukon Zhu Lei Setthaya Naruemon Chindawong Chakkresit Song Wei Guo 《Catalysis Letters》2022,152(6):1639-1650
Catalysis Letters - The cobalt-based metal organic frameworks (Co-MOFs) catalyst has been prepared with using terephthalic acid and 4,4′-bipyridine as organic linkers by facile solvothermal... 相似文献