基于电化学老化衰退模型的锂离子动力电池外特性

当前锂离子动力电池电化学模型存在模型复杂、建模难度大、计算效率低、老化评估效果差的问题,本文提出一种考虑电池衰退老化的机理模型(ADME).本文首先通过有限差分法对伪二维(P2D)电化学模型进行离散降阶处理,得到简化伪二维(SP2D)模型.在SP2D模型的基础上,基于阴阳两极发生的副反应导致的衰退老化现象,提出一种考虑电池衰退老化的机理模型.其次,使用多变量偏差补偿最小二乘法实现模型参数辨识.最后通过动力电池衰退老化性能循环实验,对比分析了恒流、脉冲工况下SP2D模型和ADME模型的终端电压输出.结果表明:ADME模型较为简单、计算效率和估算精度高,可以有效评估电池容量老化衰退,得到理想的锂离子动力电池外特性曲线.     

CeO2基磨粒在化学机械抛光中的研究进展

CeO₂由于其适当的机械性能及高的化学活性，更重要的是其对Si₃N₄/SiO₂的高选择性去除，使其被广泛应用于浅槽隔离化学机械抛光工艺中。本文论述了CeO₂基抛光液的抛光机制的研究进展，从CeO₂磨料的形貌尺寸、晶体结构、力学性能方面分析了磨料性质对抛光性能的影响，并进一步讨论了CeO₂基研磨颗粒及相关辅助抛光技术在CMP应用上的研究进展。以此为CeO₂基磨料的可控制备及新型抛光技术的发展提供借鉴，并希望能够促进CeO₂基研磨颗粒在抛光工艺中作用机制的揭示，使CeO₂抛光液更广泛地应用于材料的平坦化处理中。     

Hudson模型适用性及储层微观建模应用*

为明确裂缝间相互作用对各向异性的影响，本文以Hudson模型为例分析了裂缝密度、裂缝倾角对地震波波场、弹性常数和Thomsen系数的影响规律，然后采用“基质-骨架-流体”组合化的方法进行了裂缝储层微观尺度的建模，并与实际测井资料进行了对比。结果表明该模型适用条件为低裂缝密度储层，二阶模型适用的裂缝密度范围比一阶模型大，但在裂缝密度过大时，二阶模型会出现不收敛的现象，模型便不再适用。裂缝储层纵横波速度随裂缝倾角增大而增大，纵波速度对裂缝倾角更为敏感。另外，在与实际测井曲线对比时，在高裂缝密度地层二阶模型的应用效果明显优于一阶模型，说明了在高裂缝密度储层考虑裂缝间的相互作用的必要性。     

Trimetaphosphate-induced chiral selection between amino acid and nucleoside using 15N-31P coupling NMR

Life on Earth uses a common set of L-amino acids （L-aa） to construct proteins and D-nucleosides （D-Nu） to form nucleic acids,which serve as the carrier of genetic information.Herein,we reveal the intrinsic mechanism of chiral selection of L-aa and D-Nu from the perspective of chemical origin of life.This work employed¹⁵N-labeled L-aa and performed one-pot synthesis of nucleotide amidate of amino acid （N-aa-NMP） using equal amounts of L-¹⁵N-aa and D-¹⁴N-aa with D-...     

Natural scaffolds-inspired synthesis of CF3-substituted macrolides enabled by Rh-catalyzed C–H alkylation macrocyclization

The development of innovative strategies and methods to provide natural product-like macrocycles not accessible by biosynthesis, but endowed with novel bioactivities and simplified structure, is highly desirable. Inspired by the key scaffolds of rapamycin and FR252921, herein, we report a Rh（III）-catalyzed C–H alkylation macrocyclization, which enables access to CF3-substituted macrolides. DFT calculations reveal that the chemoselectivity between C–H alkylation and olefination macrocyclization w...     

Achieving an electron transfer photochromic complex for switchable white-light emission

Tuning white-light emission via free radicals is still a challenge in molecular-based functional materials.Herein, a new photoactive Zn²⁺oxalate-based chain containing a polypyridine ligand was designed and synthesized with remarkably bifunctional photochromism and photo-actuated greenish white-light emission after UV, sunlight or Xe lamp light irradiation at room temperature. The photo-actuated coloration process was induced by the photogeneration of stable radicals originated from i...     

Self-assembly of three Ag-polyoxovanadates frameworks for their efficient construction of C–N bond and detoxification of simulant sulfur mustard

Three imidazole-modified Ag-polyoxovanadates frameworks（APFs） with a controllable molar ratio of Ag+to polyoxovanadates（POVs） [Ag（IM）₂]₂V₄O₁₂·2Ag（IM）₂（APF-1）, [Ag₂（1-e IM）₄]₂[Ag（1-e IM）₂]3·2Ag（1-e IM）₂·3（1-He IM）[V₁₀O₂₈]₂（APF-2） and [Ag（1-pIM）₂]₃[HV₁₀O₂₈]·2Ag（1-pIM）₂·2H₂O（APF-3）(IM = imidaz...     

Defect-rich and ultrathin nitrogen-doped carbon nanosheets with enhanced peroxidase-like activity for the detection of urease activity and fluoride ion

Although carbon nanozymes have attracted great interest due to their good biocompatibility, low cost,and high stability, designing high-active carbon nanozymes still faces great challenges. Herein, ultrathin nitrogen-doped carbon nanosheets with rich defects(d-NC) were prepared through a high-temperature annealing process, using potassium chloride and ammonium chloride as templates. Owing to the large specific surface area, rich defects and the high exposure of active sites, the proposed d-NC na...     

H2S-assisted growth of 2D MS2（M=Ti,Zr,Nb）

2D transition metal dichalcogenides（TMDCs） have drawn an enormous amount of attention due to their fascinating properties and application potential in next-generation information process and storage. However, the lack of proper synthesis approach limits their application. Here, we report a controllable synthesis method to grow ultrathin MS2（M = Ti, Nb, Zr） nanosheets with H2S-assisted chemical vapor deposition（CVD）. We found that the presence of H2S plays an important role to control the morphol...