Surface-anchoring zwitterionic antioxidant enables efficient,stable,and scalable all-perovskite tandem solar cells

Lead-halide perovskite photovoltaics(PVs)have achieved impressive progress in power conversion efficiencies(PCEs)over the past ten years,accelerating their step forward to next-generation commercial PV technologies[1].As a leading candidate for perovskite PVs,monolithic all-perovskite tandem solar cells(PTSCs)have achieved the best24.8%for small-area devices(0.049 cm^2)in 2019。     

抛光粉颗粒度对高功率激光玻璃材料抛光效率和粗糙度的影响

磷酸盐钕玻璃、熔石英和BK7是3类用于激光惯性约束聚变(ICF)装置主要光学元件材料.实验中采用不同平均粒径的氧化铈抛光粉对上述3类材料分别进行抛光,对特定材料抛光去除量和抛光粉平均粒径的关系进行了研究.实验表明:由于材料的物理和化学特性不同,特定的材料需选用相应平均粒径大小的抛光粉才能达到最佳的抛光效率.实验还就上述3类高功率激光玻璃材料抛光中各个阶段的抛光粗糙度与抛光粉平均粒径的关系进行了研究,结果表明:某一规格抛光粉的粒径对不同特性材料抛光后的表面粗糙度影响表征情况不同.     

论自我知识的构成主义观点

构成主义观点致力于在自然主义的心灵图景中解释自我知识的特殊性与第一人称权威。为此,它主张高阶信念和一阶态度不是相互独立的,而是有着构成性的关系。概念论解释试图从认识主体的概念能力,特别是批判性推理的能力来作出论证。默认权威观点则诉诸日常话语实践的“语法”要求,主张认识主体对自我的态度拥有先天合理的、又可由证据挫败的确信。通过引入“以言行事”的思路,构成主义有希望确立起合理、审慎、有节制的第一人称权威观点。     

Thermodynamic Resolution of Pharmaceutical Precursor Modafinil Acid on the Basis of Chiral-at-Metal Strategy

Main observation and conclusion Chiral-at-metal strategy was developed to resolve the essential sulfoxide pharmaceutical intermediates R-modafinil acid and its ...     

Versatile Graphene-Isolated AuAg-Nanocrystal for Multiphase Analysis and Multimodal Cellular Raman Imaging

Main observation and conclusion Surface-enhanced Raman spectroscopy(SERS)-based bioanalytical technique involves the interaction of SERS-active substrate with c...     

β-cyclodextrin Sensitized Spectrofluorimetry for the Determination of Abiraterone Acetate and Abiraterone

A novel spectrofluorimetric method to determine abiraterone acetate and its active metabolite, abiraterone was developed, based on the fact that fluorescence intensity of abiraterone acetate and abiraterone could be enhanced in β-cyclodextrin (β-CD) due to the formation of the inclusion complex. The inclusion interaction of β-CD and abiraterone acetate and the β-cyclodextrin sensitized spectrofluorimetry was examined. The various factors influencing fluorescence were discussed in details. The results showed that under the optimized conditions, the linear range of calibration curve for the determination of biraterone acetate and abiraterone was 0.20?~?6.0 μg/mL, and the detection limit (LOD) was 6.8 (r?=?0.997) or 6.6 ng/mL (r?=?0.996), respectively. No interference was observed from common co-existing substances or pharmaceutical excipient. The method was successfully applied to the analysis of abiraterone acetate in pharmaceutical formulation and abiraterone in human serum/urine.     

Annihilation of persistent slip bands and its effect on the fatigue life of copper single crystals

In single-slip-oriented copper single crystals, which were cyclically deformed under constant plastic shear strain amplitude control, a persistent slip band (PSB) was initiated on the persistent slip line (PSL) that first formed in the matrix vein dislocation structure. During intermediate temperature recovery (ITR) treatment in vacuum at 245 to 400°C, the variations in dislocation configurations and other defects of fatigued specimens were studied by using the scanning electron microscopy (SEM) electron channelling contrast (ECC) and the positron annihilation life (PAL) techniques. The results show that the ladders in the PSBs became curved and broken, or escaped locally until the PSBs disappeared completely during ITR treatment. The annihilation of the PSBs and other dislocation structures in the fatigued specimens prolonged the fatigue life to a certain extent.     

Imide‐functionalized naphthodithiophene based donor‐acceptor conjugated polymers for solar cells

Donor‐acceptor conjugated polymers containing a new imide‐functionalized naphthodithiophene (INDT) as the acceptor unit and a 2,2'‐bithiophene with varied substituents as the donor unit have been synthesized. The bandgaps of these polymers depend strongly on the dihedral angle of the 2,2'‐bithiophene unit. The 3,3'‐dialkoxy substitution (polymers PDOR / PBOR ) leads to near planar bithiophene conformation due to the well‐known S–O short contact, while the 3,3'‐dialkyl substitution (polymer PDR ) results in significant twisting due to the steric effect. Consequently PDOR / PBOR shows the lowest bandgap of 1.82/1.85 eV while PDR has a bandgap of 2.38 eV. Bulk‐heterojunction solar cells of the polymer/fullerene blends have been fabricated. Preliminary results show that PBOR gives the best device performance with power conversion efficiencies as high as 2.45% in air without any thermal annealing treatment, indicating the promising potential of INDT‐containing conjugated polymers for efficient solar cells. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3818–3828     

厄尔尼诺和南方涛动海气耦合模型中参数估计的变分方法

提出一种基于变分原理估计厄尔尼诺和南方涛动海气耦合模型中未知参数的方法. 首先将所研究的非线性海气耦合动力方程引入到目标泛函中; 接着利用变分方法导出伴随方程和待辨识参数泛函梯度的公式; 然后设计了估计未知参数的算法.数值试验结果表明变分方法是一 种能有效估计海气耦合非线性系统未知参数的方法.     

Substrate-controlled and highly stereoselective synthesis of 2-aminobut-2-ene-1, 4-diones

2-Methylthio-substituted 1,4-enediones, obtained from readily available aryl methyl ketones, were reacted with primary or secondary amines to afford the desired 1,4-diaryl-2-aminobut-2-ene-1,4-diones in excellent yields with high Z/E-stereoselectivity.