Thermal properties of hierarchical YSZ and LZO ceramic microspheres with multi-scaled voids investigated by using theoretical,experimental and simulation methods

Heat transfer within ceramic feedstock powders is still unclear, which impedes optimization of the thermal and mechanical properties of the thermal sprayed coatings. The microspheres (yttria-stabilized zirconia YSZ and lanthanum zirconate LZO) were prepared via the electro-spraying assisted phase inversion method (ESP). The thermal properties of the two ESP microspheres and a commercial hollow spherical powder (HOSP) were investigated by using theoretical, experimental, and simulation methods. Thermal conductivity of the single microsphere was estimated via a novel nest model that was derived from the Maxwell-Eucken 1 and the EMT model. Thermal conductivity of a single YSZ/LZO-ESP microsphere prepared at 1100–1200 °C was within 0.36–0.75 W/m K, which was ～ 20 % lower than that of a single YSZ-HOSP microsphere with a similar porosity. Heat flux simulation showed that high tortuosity around the multi-scaled voids of the ESP microsphere led to a more efficient decrease in thermal conductivity compared with total porosity.     

Sustainable phenolic thermosets coatings derived from urushiol

The over-exploitation of finite fossil resources and/or the increased environmental and sustainable awareness inspire scientists and technologists to search for inexpensive alternatives from renewable chemicals. Phenol formaldehyde (PF) resins, the oldest type of synthetic polymers with good mechanical properties and heat resistance, are widely used in the production of coatings, laminates, molding compositions, and glues. Here, biobased urushiol-derived PF resins were synthesized from the alkali-catalyzed reaction between urushiol and formaldehyde. The chemical compositions and molecular structures of resole resins were characterized by carbon-13 nuclear magnetic resonance and Fourier transform infrared spectroscopy, and their curing behaviors were studied by differential scanning calorimetry. The as-prepared urushiol-derived resole resins had methylol (Ph−CH₂OH), ortho- and para-hemiformal groups (Ph−CH₂OCH₂OH), and the para−para/ortho−para/ortho−ortho links of methylene groups (Ph−CH₂−Ph), whereas the resole resins had low curing temperatures at about 100–113°C. Additionally, given the long side alkyl group moiety on the aromatic rings of urushiol, the films of cured urushiol-derived resole resins had low glass transition temperatures of 132 ± 2°C. Furthermore, the as-prepared urushiol-derived coatings exhibited excellent physical and mechanical properties.     

中国传统饮食文化融入食育路径研究

为国民身体素质、探索具有中国特色的现代食育之路，必须深入分析与探索中国饮食文化中的食育理念。文章以传统饮食文化为出发点和落脚点，概括出医食同源、饮食有节、饮食有礼等先进的食育观点。分析传统饮食与现代食育的关系，认为食育是弘扬传统饮食文化的重要途径，传统饮食文化是发展现代食育的基础。但探索现代食育仍面临着西方快餐文化冲击和国民食育进程缓慢等困境，必须采取强化国民食育意识、加强食育法制建设、健全食育教育体系、推进食育试点工作等措施促进中国传统饮食文化融入食育体系建设，真正探索具有中国特色的食育之路。     

High-performance Pb(Ni1/3Nb2/3)O3-PbZrO3-PbTiO3 ceramics with the triple point composition

Ternary 0.552Pb(Ni_1/3Nb_2/3)O₃-xPbZrO₃-(0.448-x)PbTiO₃ (PNN-PZ-PT) ceramics near the triple point compositions were fabricated by an improved two-step sintering method. The triple point composition 0.552PNN-0.135PZ-0.313PT ceramic has outstanding piezoelectric performance with piezoelectric coefficient d₃₃ = 1200 pC/N. Its easy fabrication and low cost make this piezoelectric material an excellent candidate for high sensitivity sensors and ultrasonic transducers. The evolution of domain structures for ceramics with composition near the triple point provides deeper insight into the mechanism of ultrahigh piezoelectric properties of PNN-PZ-PT ceramics.     

循证之证与康复之途*—— CCRC社区中的康复花园循证设计探索

疫情下医养机构封闭化管理已经步入 常态化，老年居民的心理健康受到了抑郁、焦虑 等问题的挑战。康复花园作为养老社区中重要 的心理生理康复空间，需以循证设计为原则， 为新形势下的养老社区提供切实可行的康复空 间。本文以西南地区某持续照护型（CCRC）养 老社区项目实践为载体，梳理阐述循证设计在 康复花园中完整的运用实践路径，总结我国循 证设计流程模型，为风景园林的循证实践提供 全链条式的解析和验证。本文尝试提出基于系 统医学评估指标的证据收集创新体系，为康复 花园循证设计提供运用实例，对康复花园的康 复绩效提出基于证据的定量评估模式。     

阿尔泰南缘北塔山组火山岩锆石U-Pb定年及地质意义

新疆阿尔泰南缘北塔山组火山岩较为发育。本文对新疆阿尔泰南缘默色克奥依一带北塔山组火山岩进行地球化学分析和年代学研究。研究表明：U-Pb锆石年龄为（384.3±4.0Ma）Ma，为中泥盆世；该组火山岩属于钾质钙碱性系列，全碱（Na2O+K2O=2.07%-6.49%）和YiO2（0.24%-0.64%）含量较低，K2O含量（1.11%-4.04%）变化较大，稀土元素含量（∑REE）较低。稀土元素显示其轻稀土富集且分馏不明显；δEu值均大于1，为Eu富集型；δCe值均小于1，为Ce亏损型。该组火山岩微量元素P明显富集，K、Rb、Ba等大离子亲石元素（LILE）略富集，亏损Ta、Zr、Hf、Ti等高场强元素（HISF）。结合前人研究，本文认为默色克奥依一带北塔山组火山岩形成于岛弧及与俯冲过程有关的活动大陆边缘造山带环境，为泥盆纪古大洋俯冲消减过程中，俯冲板片脱水产生的流体交代上覆地幔楔部分熔融的产物。     

Exploring the role of the sharing economy in disasters management

Improvements in information and communications technologies (ICTs) have facilitated the inclusion of the sharing economy (SE) in societies more than ever. In the aftermath of recent disasters, the SE played significant roles to help the affected people and support official responders. However, the literature has not effectively explored these roles, and thus, no framework can support the systematic inclusion of the SE in disasters management. This paper aims to address the gap through a two-stage exploratory research approach. First, we conduct a systematic literature review to identify the extent to which the SE is taken into consideration in disasters. After that, we investigate the role of three Iranian SE-based companies that were involved in the 2019 Iran floods response. We collect empirical data by conducting semi-structured interviews and reviewing official reports.Our findings indicate that very few studies discuss the different roles of the SE in disasters, although SE companies have often provided effective solutions to address critical post-disaster logistics challenges. Four research propositions are presented to describe emerging roles for SE companies. The contribution of our study is twofold. First, our research identifies the different roles that the SE could play in disasters and therefore, brings a new perspective to the literature. Second, the study suggests opportunities for collaboration and partnership models from the point of origin to delivery that can support coordination and logistics in disasters.     

Conductor selection and economic analysis of D.R. congo–guinea ±800 kV UHVDC transmission project

Africa is embracing new opportunities featured with industrialization, urbanization and regionalization. Based on co-development of ‘Electricity, Mining, Metallurgy, Industry and Trade’ and grids interconnection proposed by Global Energy Interconnection Development and Cooperation Organization (GEIDCO), the high-quality hydropower resource of the Congo River can be exploited in large scale under the wide-range interconnected framework of African Energy Interconnection (AEI), forging a new engine for Africa economy. The transmission distance of the Congo River hydropower reaches 6,000 km at its farthest end in North Africa, which brings forth challenges to economics of proposed projects. Under this novel continental energy interconnection scheme in Africa, economics of those projects have not yet been in detail studied. This paper has implemented China’s mature engineering experiences and analytical tools of UHVDC project planning into the AEI structure, through exploring the economic behavior of ultra-long distance UHVDC projects in the scope of conductor selection in the Congo River hydropower transmission for the first time, and has provided concerned parties with a technical and analytical results of their economics comparison. This paper has chosen the D.R. Congo - Guinea ±800 kV UHVDC project as a typical example. Its preliminary system planning is introduced and three types of conductor are selected for scheme comparison. Later in this paper, the transmission loss, total investment and equivalent annual cost of the project have been calculated and analyzed. In the final part, sensitivity analysis results of the annual cost to utilization hours, transmission loss, loss tariff and construction cost has been provided     

Governance choices and policy outcomes in the Latin American and caribbean electricity sector

The paper first provides, for Latin America and the Caribbean, country-specific synthetic quantitative measures of the degree of adoption of governance reforms in the electricity sector, focusing on four key dimensions (market structure, private sector participation (PSP), regulatory autonomy and operational organization). These measures are then correlated with standard policy performance outcomes measures. The findings suggest that, the reforms, considered jointly, were statistically significantly associated with higher technical and process quality but not with social or service improvements. Considered individually, increased regulatory autonomy enjoyed the highest positive correlation with desirable outcomes, but PSP has no significant correlation with any of the outcomes. In sum, as of 2018, governance reforms, considered jointly, had still not delivered on some promised payoffs, notably in addressing energy poverty, although the sensitivity analysis suggests that, for some indicators, the relationships are stronger for larger than for smaller countries.