Non-Halogenated-Solvent Processed and Additive-Free Tandem Organic Solar Cell with Efficiency Reaching 16.67%

Organic solar cells (OSCs) have recently reached a remarkably high efficiency and become a promising technology for commercial application. However, OSCs with top efficiency are mostly processed by halogenated solvents and with additives that are not environmentally friendly, which hinders large-scale manufacture. In this study, high-performance tandem OSCs, based on polymer donors and two small-molecule acceptors with different bandgaps, are fabricated by solution processing with non-halogenated solvents without additive. Importantly, the two active layers developed from non-halogenated solvents show better phase segregation and charge transport properties, leading to superior performance than halogenated ones. As a result, a tandem OSC with high efficiency of up to 16.67% is obtained, showing unique advantages in future massive production.     

Ni1−xCoxSe2?C/ZnIn2S4 Hybrid Nanocages with Strong 2D/2D Hetero-Interface Interaction Enable Efficient H2-Releasing Photocatalysis

Designing a semiconductor-based heterostructure photocatalyst for achieving the efficient separation of photogenerated electron-hole pairs is highly important for enhancing H₂ releasing photocatalysis. Here, a new class of Ni_1−xCo_xSe₂–C/ZnIn₂S₄ hierarchical nanocages with abundant and compact ZnIn₂S₄ nanosheets/Ni_1−xCo_xSe₂^ C nanosheets 2D/2D hetero–interfaces, is designed and synthesized. The constructed heterostructure photocatalyst exposes rich hetero-junctions, supplying the broad and short transfer paths for charge carriers. The close contacts of these two kinds of nanosheets induce a strong interaction between ZnIn₂S₄ and Ni_1−xCo_xSe₂ C, improving the separation and transfer of photo-generated electron-hole pairs. As a consequence, the distinctive Ni_1−xCo_xSe₂ C/ZnIn₂S₄ hierarchical nanocages without using additional noble-metal cocatalysts, display remarkable H₂-relaesing photocatalytic activity with a rate of 5.10 mmol g⁻¹ h⁻¹ under visible light irradiation, which is 6.2 and 30 times higher than those of fresh ZnIn₂S₄ nanosheets and bare Ni_1−xCo_xSe₂ C nanocages, respectively. Spectroscopic characterizations and theory calculations reveal that the strong interaction between ZnIn₂S₄ and Ni_1−xCo_xSe₂ C 2D/2D hetero-interfaces can powerfully promote the separation of photo-generated charge carriers and the electrons transfer from ZnIn₂S₄ to Ni_1−xCo_xSe₂ C.     

梁思成佚文《说建筑品格精神之所在》介绍

1943 年 6 月发表于《社会教育季刊》第 2 期的《说建筑品格精神之所在》是梁思成的一篇佚文。本文对其写作的背景、契机、目的和主要内容进行了研究和分析。作者认为，这篇文章是梁思成建筑美学思想的首次较为全面的表述，概括而言就是建筑要在解决实际问题的同时，以经济的手段达到主观愿望与现实条件、材料的施工与结构的功用、科学与艺术，以及物质与精神之间关系的相宜和平衡。它提出的时间正是“抗战转入胜利时期”，对于尚在抗日战争之中的建设和即将到来的战后重建都有现实的指导意义。     

Authenticity green coffee bean species and geographical origin using near-infrared spectroscopy combined with chemometrics

To prevent the adulteration of agricultural resources and provide a solution to enhance the green coffee bean supply chain, authentication using the near-infrared spectroscopy (NIRS) technique was investigated. Partial least square with discrimination analysis (PLS-DA) models combined with various preprocessing methods were built from NIR spectra of 153 Vietnamese green coffee samples. The model combined with the standard normal variate and the first order of derivative yielded excellent performance in predicting coffee species with the error cross-validation of 0.0261. PLS-DA model of mean centre and first-order derivative spectra also yielded good performance in verifying geographical indication of green coffee with the error of 0.0656. By contrast, the predicting abilities of post-harvest methods were poor. The overall results showed a high potential of the NIRS in online authentication practices.     

岩移沉降观测中数据缺失的一种估算方法

在矿区的岩移沉降观测过程中,由于环境、人为等原因导致观测数据缺失问题,损害了整体观测数据的完整性,影响后续沉降趋势预测.文中提出了一种最大期望算法,通过计算极大似然估计,交替执行E步和M步,最终得到观测缺失数据填补值.利用某矿区实测数据进行实验,对比分析发现最大期望算法对缺失数据填补更接近实际测量值,在实际应用中有一定参考价值.     

Reversal of the Inflammatory Responses in Fabry Patient iPSC-Derived Cardiovascular Endothelial Cells by CRISPR/Cas9-Corrected Mutation

The late-onset type of Fabry disease (FD) with GLA IVS4 + 919G > A mutation has been shown to lead to cardiovascular dysfunctions. In order to eliminate variations in other aspects of the genetic background, we established the isogenic control of induced pluripotent stem cells (iPSCs) for the identification of the pathogenetic factors for FD phenotypes through CRISPR/Cas9 genomic editing. We adopted droplet digital PCR (ddPCR) to efficiently capture mutational events, thus enabling isolation of the corrected FD from FD-iPSCs. Both of these exhibited the characteristics of pluripotency and phenotypic plasticity, and they can be differentiated into endothelial cells (ECs). We demonstrated the phenotypic abnormalities in FD iPSC-derived ECs (FD-ECs), including intracellular Gb3 accumulation, autophagic flux impairment, and reactive oxygen species (ROS) production, and these abnormalities were rescued in isogenic control iPSC-derived ECs (corrected FD-ECs). Microarray profiling revealed that corrected FD-derived endothelial cells reversed the enrichment of genes in the pro-inflammatory pathway and validated the downregulation of NF-κB and the MAPK signaling pathway. Our findings highlighted the critical role of ECs in FD-associated vascular dysfunctions by establishing a reliable isogenic control and providing information on potential cellular targets to reduce the morbidity and mortality of FD patients with vascular complications.     

Inhibiting effect of heterogeneous cations aggregation enhanced by oxygen deficiency on glass formation of BaTi2O5 melts

Although remarkable development of titanate-based glasses has been achieved, challenge remains to elucidate the correlation between structure and glass-forming properties in these systems due to their complex structure that is inconsistent with the classic Zachariasen's model. In this work, we aim to correlate the structural evolution of titanate melts to their glass-forming ability (GFA). The prototypical material barium dititanate (BaTi₂O₅, BT2) melts with different GFA were rendered by controlled melting atmospheres, and the corresponding structural changes were determined using in situ high-energy synchrotron X-ray diffraction combined with empirical potential structure refinement and ab initio molecular dynamics. The results show that BT2 melt in reducing atmosphere shows poor GFA but that in oxidizing atmosphere presents good GFA. Structural analysis demonstrates the mean coordination number of [TiO_m] polyhedra is analogous in the melt under two different atmospheres but an enhanced heterogeneous cations aggregation takes place in the melt under reducing atmosphere, which is closely related to oxygen-deficiencies. Furthermore, we reveal that the enhanced heterogeneous cations aggregation promotes crystallization (and therefore hinders glass formation) through disordering the distribution of [TiO_m] and [BaO_n] polyhedra, changing the connectivity between these polyhedra, creating more crystal-like Ti-Ti clusters, and decreasing topological disorder of BT2 melt. Our work provides a new viewpoint to understand the GFA of titanates melt from structural heterogeneity beyond the previous perspectives that only focus on [TiO_m] polyhedra.     

Estimating long-term time-resolved indoor PM2.5 of outdoor and indoor origin using easily obtainable inputs

To evaluate the separate impacts on human health and establish effective control strategies, it is crucial to estimate the contribution of outdoor infiltration and indoor emission to indoor PM_2.5 in buildings. This study used an algorithm to automatically estimate the long-term time-resolved indoor PM_2.5 of outdoor and indoor origin in real apartments with natural ventilation. The inputs for the algorithm were only the time-resolved indoor/outdoor PM_2.5 concentrations and occupants’ window actions, which were easily obtained from the low-cost sensors. This study first applied the algorithm in an apartment in Tianjin, China. The indoor/outdoor contribution to the gross indoor exposure and time-resolved infiltration factor were automatically estimated using the algorithm. The influence of outdoor PM_2.5 data source and algorithm parameters on the estimated results was analyzed. The algorithm was then applied in four other apartments located in Chongqing, Shenyang, Xi'an, and Urumqi to further demonstrate its feasibility. The results provided indirect evidence, such as the plausible explanations for seasonal and spatial variation, to partially support the success of the algorithm used in real apartments. Through the analysis, this study also identified several further development directions to facilitate the practical applications of the algorithm, such as robust long-term outdoor PM_2.5 monitoring using low-cost light-scattering sensors.     

精益六西格玛在在线检测设备测量精度分析中的应用研究

轮对尺寸在线检测设备在日常使用过程中产生一系列测量数据,但受多个因素影响,难以直接对其测量精度进行评估,因此迫切需要行之有效的测量精度分析方法.而在各行各业成熟应用的精益六西格玛管理工具中,丰富的数据图形统计工具与测量系统分析工具为解决在线检测设备测量精度分析难题提供了新的解决思路.以轮对尺寸在线检测设备为例,利用精益六西格玛数据图形统计工具与测量系统分析工具对其测量精度进行了一系列分析,证明了该研究方法适合用于在线检测设备在非试验条件下产生的测量数据基础上的测量精度分析.