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Solvent polarity-induced photoluminescence enhancement (SPIPE): A method enables several-fold increase in quantum yield of silicon nanoparticles

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Nano Research 2019年第2期12卷 315-322页

作者： Xiao-Bin Shen Bin Song Bei Fang Xiao Yuan you-yong li Shun-Yi Wang Shun-Jun Ji Yao He Laboratory of Nanoscale Biochemical Analysis Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC) Soochow University Suzhou 215123 China Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 China

Fluorescent silicon nanoparticles (SiNPs) bring exciting opportunities for long-awaited silicon-based optical application, while intrinsic indirect band gap of silicon severely limits photoluminescent quantum yield (PLQY) of SiNPs. To address this critical issue, we herein demonstrate a facile and general method, Le., solvent polarity-induced photoluminescence enhancement (SPIPE)1 yielding several-fold increase in quantum yield (QY) of SiNPs. Typically, different kinds of 4-substituented-1,8-naphthalic anhydride molecules, Le., 4-Br-1,8-naphthalic anhydride (BNA)1 4-triphenylamino-1,8-naphthalic anhydride (TPNA)1 and 4-dimethylamino-1,8-naphthalic anhydride (DMNA)1 are rationally designed and synthesized, which serve as surface ligands for the production of BNA-, TPNA-, and DMNA-capped small-sized (diameter:- 3.8-5.8 nm) SiNPs with QY of^8%,~15%,~16%, respectively. Of particular significance, QY of the resultant SiNPs could be greatly enhanced from^10% to^50% through the SPlPE strategy. Taken together with the theoretical calculation and the results of time-correlated single photon counting, we reveal that actived excited-state charge transfer interactions between surface-covered ligand and silicon oxide coating would be responsible for the observed QY enhancement. Moreover, other five kinds of solvents (i.e., methanol, isopropanol, dimethyl sulfoxide, N,N-dimethylformamide, and acetonitrile) are further employed for the SiNPs treatment, and similar improvement of QY values are observed, convincingly demonstrating the universal evidence of SPIPE of the SiNPs.

关键词： silicon nanoparticles quantum yield fluorescent surface ligand solvent polarity

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Application of Genetic Algorithm to the QSAR Research of Pyrrolobenzothiazepinones and Pyrrolobenzoxazepinones-Novel and Specific Non-Nucleoside HIV-1 Reverse Transcription Inhibitors

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Chinese Chemical Letters 1998年第7期9卷 651-654页

作者： Ting Jun HOU Jun Mei WANG you yong li Xiao Jie XU(Chemistry department, Beida-Jiuyuan Molecular Design Laboratory, Peking University,Beijing 100871) Chemistry Department Beida-Jiuyuan Molec. Des. Laboratory Peking University Beijing 100871 China

Genetic Algorithm (GA) was used to study the quantitative structural parameters and activity relationship of pyrrolobenzothizepinones and pyrrolobenzoxazepinones's inhibitory activities with non-nucleoside HIV-1 reverse transcriptase (RT). A group of linear polynomial models with good relationship have been built to get some useful information that other methods can not offer.

关键词： QSAR GA(genetic algorithm) HIV

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Fludarabine and cytarabine combined chemotherapy followed by transfusion of donor blood stem cells for treating relapse of acute leukaemia after allogeneic haematopoietic stem cell transplantation

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Chinese Medical Journal 2008年第18期121卷 1770-1774页

作者： you yong li Qiu-bai CHEN Zhi-chao li Wei-ming XIA ling-hui ZHOU Hao ZOU Ping Institute of Haematology Union Hospital Tongji Medical College of Huazhong University of Science and Technology WuhanHubei 430022 China

Background Relapse remains an obstacle to successful allogeneic haematopoietic stem cell transplantation （allo-HSCT） for patients with acute leukaemia and no standard treatment is available. We assessed fludarabine and cytarabine with transfusion of donor haematopoietic stem cell in treating the relapse of acute leukaemia after allo-HSCT. Methods Seven patients, median age 34 years, with relapse of acute leukaemia after allo-HSCT received combination chemotherapy of fludarabine with cytarabine for 5 days. Five patients suffered from acute myeloid leukaemia （2 refractory） and 2 refractory acute lymphoblastic leukaemia. After the transplantation, the median relapse time was 110 days （range, 38-185 days）. Two days after chemotherapy, 5 patients received infusion of donor＇s peripheral blood stem cells, mobilized by granulocyte colony stimulating factor. No prophylactic agents of graft versus host diseases were administered, Results Six patients achieved haematopoietic reconstitution. DNA sequence analysis at day 30 after treatment identified all as full donor chimera type. The median observation time was 189 days. After the treatment, the median time for neutrophilic granulocyte value 〉0.5×10^9/L and for platelet value 〉20×10^9/L were 13 days （range, 10-18 days） and 15 days （range, 11-24 days）, respectively. Graft versus host disease occurred in 2 patients （acute） and 3 （chronic）. Five patients suffered from pulmonary fungal infection （2 died）, 3 haemorrhagic cystitis and 2 cytomegalovirus viraemia. The other patients died of leukaemia related deaths. Three patients with chronic graft versus host disease who had received donor peripheral blood stem cells reinfusion have survived for 375 days, 232 days and 195 days, respectively. Conclusions Fludarabine with cytarabine plus the donor haematopoietic stem cell should be considered as an effective therapeutic regimen for relapse of acute leukaemia after alio-HSCT. The disease free state of patients may increase, though with

关键词： fludarabine allogeneic haematopoietic stem cell transplantation relapse acute leukaemia

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Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu Guo Lanyue Zhang Gening Du Hao you Junfeng Huang Mudong Tu Hua li yong Peng Wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： X ray photoelectron spectroscopy

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支架现浇法塔梁同步施工独塔混凝土斜拉桥仿真分析

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公路交通科技 2021年第12期38卷 64-72页

作者：游勇利刘辉江西省公路科研设计院有限公司江西南昌330002 江西省交通工程集团有限公司江西南昌330038 武汉理工大学交通与物流工程学院湖北武汉430063

独塔斜拉桥是高次超静定结构,塔梁固结,结构受力复杂多变,为保证桥梁施工过程安全以及实现设计的合理成桥状态,采用有限元软件建立空间模型进行了施工全过程仿真分析,并应用仿真分析结果确定了施工方案。针对地势平坦、河床地形平缓、... 详细信息

独塔斜拉桥是高次超静定结构,塔梁固结,结构受力复杂多变,为保证桥梁施工过程安全以及实现设计的合理成桥状态,采用有限元软件建立空间模型进行了施工全过程仿真分析,并应用仿真分析结果确定了施工方案。针对地势平坦、河床地形平缓、水位较浅或桥下净空较低等桥位区,优先选用支架现浇法塔梁同步施工法施工独塔斜拉桥。以支架现浇法塔梁同步施工的某独塔混凝土斜拉桥为背景,建立了计算模型,开展了独塔斜拉桥施工过程力学性能研究。江西省境内某大桥为2×132 m独塔混凝土斜拉桥,针对该桥结构特点、受力模式,采用Midas Civil建立了整体模型进行施工全过程仿真计算,得出了结构最不利受力位置和最不利施工工况,从而确定了下一步现场施工重点监测断面及控制目标值。同时明确了支架现浇法施工主梁、塔梁同步施工、中塔柱施工临时横撑千斤顶顶推力控制、主梁竖向位移、塔梁固结处应力、拉索索力值及结构体系转换是控制的重点。结果表明:该桥主梁、主塔、斜拉索在各拟定施工阶段均满足控制要求,且具有一定安全储备;主梁有支架施工数值模型中模拟方法有效,塔梁同步施工仿真分析方法合理可行,可为类似支架现浇法塔梁同步施工混凝土斜拉桥仿真计算分析提供借鉴参考。

关键词：桥梁工程独塔斜拉桥有限元法施工控制塔梁同步施工仿真分析

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Unraveling post-growth mechanisms of monolayer CsPbBr3 nanocubes:Laser-enhanced transformations and cathodoluminescence-electron microscopy correlations

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Journal of Energy Chemistry 2025年第1期100卷 146-156页

作者： Mingxing li Xiaoge Wang Xiaofan Cao Zhiqun He Chunjun liang Mingxing Chen Jing Ju Fangtian you Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing National Laboratory for Molecular Sciences (BNLMS) College of Chemistry and Molecular Engineering Peking University

Lead-halide perovskite nanoparticles（LHP NPs） are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term *** research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.

关键词： Energy dispersive spectroscopy

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Weak KAM theory for two classes of almost periodic Hamiltonian systems

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Science China Mathematics 2025年

作者： Xun Niu Kaizhi Wang yong li School of Mathematics and Statistics Center for Mathematics and Interdisciplinary SciencesNortheast Normal University School of Mathematical Sciences Shanghai Frontier Science Center of Modern Analysis (CMA-Shanghai)Shanghai Jiao Tong University Institute of Mathematics Jilin University

The purpose of this paper is to investigate the dynamics of Bohr almost periodic and Levitan almost periodic Hamiltonian systems via the weak KAM theory. We obtain minimal measures and weak KAM solutions in both cases. The weak KAM solution is a weak solution to the Hamilton-Jacobi equation, which formally transforms the original Hamiltonian systems into an integrable one. Consequently, we get the existence of an invariant torus in the aforementioned weak sense.

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Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang Wenwu Zhang Gang li Xing Cheng Peiqiang Su yong Wan Xiang li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

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Buried interface bridging for inverted cesium-formamidinium triiodide perovskite solar cells with long operational stability

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Science China Chemistry 2025年第1期68卷 163-173页

作者： Chenhui Zhang Chunjun liang Fulin Sun Ting Zhu Xinghai Huang Yuzhu Guo Xinyu Guo Kunyang Ge Dan li Fangtian you Zhiqun He Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic TechnologyBeijing Jiaotong University Department of Physics School of Physical Science and Engineering Beijing Jiaotong University

In the field of perovskite solar cells(PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride(PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs,aiming to enhance the uniformity of self-assembled monolayers(SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress,thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency(PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology.

关键词： defect-induced recombination buried interfaces inverted perovskite solar cells crystallization lattice mismatch

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan yong liang Weipeng li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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