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Aromatic Polyimides with Tertbutyl-substituted and Pendent Naphthalene Units:Synthesis and Soluble,Transparent Properties

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Chinese Journal of Polymer Science 2015年第8期33卷 1074-1085页

作者： Chan-juan Liu mei mei Xiang-lin Pei 黄孝华 Chun Wei Key Laboratory of New Processing Technology for Nonferrous Metal & Materials Ministry of Educationand School of Material Science and EngineeringGuilin University of Technology Ministry of Education Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical ScienceGuangxi Normal University

A novel non-coplanar aromatic diamine monomer, 3,3＇-ditertbutyl-4,4＇-diaminodiphenyl-4＂-naphthylmethane （TAPN） was synthesized by a condensation reaction of 2-tertbutylaniline and 1-naphthaldehyde under catalyst hydrochloric acid. The structure of the monomer was confirmed by FTIR, NMR, elementary analysis and mass spectrometry. A series of aromatic polyimides （PIs） were synthesized via conventional one-step polycondensation from TAPN and various commercial aromatic dianhydrides. All of the PIs exhibit excellent solubility in common organic solvents, even in low boiling point solvents such as chloroform （CHC13）, tetrahydrofuran （THF） and acetone. The PIs present outstanding thermal stability with the glass transition temperature （Tg） ranged from 299 ℃ to 350 ℃, and the temperature at 10% weight loss ranged from 490 ℃ to 504 ℃, and high optical transparency with the cutoff wavelengths of 306-356 nm. Moreover, the flexible and tough PI films have prominent mechanical properties with tensile strengths in the range of 77.6-90.5 MPa, tensile modulus in the range of 1.8-2.4 GPa and elongation at break in the range of 6.3%-9.5%, as well as lower dielectric constant （2.89-3.12 at 1 MHz） and lower moisture absorption （0.35%-0.66%）.

关键词： Polyimides Solubility Dielectric constant Tertbutyl Naphthyl.

pH-Sensitive nanoscale materials as robust drug delivery systems for cancer therapy

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Chinese Chemical Letters 2020年第6期31卷 1345-1356,F0003页

作者： Zhaoqing Shi Qianqian Li lin mei School of Pharmaceutical Sciences(Shenzhen) Sun Yat-sen UniversityShenzhen 518107China Tsinghua Shenzhen International Graduate School.Tsinghua University Shenzhen 518055China

Cancer is one of the diseases that have the highest mortality,which threatens the human *** functions as the most widely used strategy in clinic to treat cancer,still exists urgent problems,like lacking selectivity and causing severe side *** to detailed researches on the metabolism,functions and histology of cancer tissues,many different features of cancer are uncovered,like lower pH in microenvironment,abnormal redox level in intracellular compartments and elevated expression level of several enzymes and ***,the development of smart nanoparticles that response to tumor specific microenvironment has lighted up hope for selective cancer ***,this review mainly focuses on pH-sensitive nano scale materials for anti-cancer drug *** summarized the formation progress of acidic tumor microenvironment,the mechanism of pHresponsive drug delivery system and nanomaterials that responsive to acidic pH in tumor microenvironment.

关键词： Cancer therapy Drug delivery systems Nanoparticles pH-sensitive material

Late Paleozoic–Early Mesozoic tectonic evolution of the Zongwulong Shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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Journal of Earth Science 2025年

作者： Yonghui Zhao Chen Wu Jie Li Peter J.Haproff lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau experienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been extensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 Ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mixed crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental extension occurred in the northern margin of the Qaidam continent (ca. 416 Ma–292 Ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 Ma–233 Ma); and (3) subsequent late Triassic intracontinental extension (ca. 233 Ma–215 Ma). Our results suggest that the late Paleozoic–early Mesozoic development of the Zongwulong Shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu Yang Feng Chunming Yang lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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Holographic magnetized chiral density wave

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Chinese Physics C 2018年第11期42卷 85-92页

作者： Yanyan Bu shu lin School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Department of Physics Harbin Institute of TechnologyHarbin 150001China

We explore the end point of the helical instability in a finite density, finite magnetic field background discussed by Kharzeev and Yee. The nonlinear solution is obtained and identified with the （magnetized） chiral density wave phase in the literature. We find there are two branches of solutions, which match the two unstable modes found before. At large chemical potential and magnetic field, the magnetized chiral density wave can be thermodynamically preferred over the chirally symmetric phase and chiral symmetry breaking phase. Interestingly, we find an exotic state with vanishing chemical potential at large magnetic field. We also attempt to clarify the role of anomalous charge in the holographic model.

关键词： chiral density wave holography axial anomaly

Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun BAI Zhang ZHU Xiaoli WANG shuoshuo MU lin GONG Liang College of New Energy China University of Petroleum (East China) Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of Technology

A 3D simulation using Computational Particle Fluid Dynamics（CPFD） methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed（CFB） *** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO2and *** the combustion reaction progresses,it becomes evident that the concentration of CO2progressively increases,while the concentration of O2concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide（NO） and sulfur dioxide（SO2） emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide（SO3） or bound in sulfates,reducing *** steady state in the simulation,the SO2mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s-1at 4 m at the bottom of the furnace to a peak of 0.078 kg·s-1at 8 m in the center,and then decreasing to 0.06 kg·s-1at 20m at the top of the furnace.

关键词： Sulfur dioxide

Prevalence and incidence of heart failure among community in China during a three-year follow-up

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Journal of Geriatric Cardiology 2023年第4期20卷 284-292页

作者： Lu FU Jun-Rong JIANG Wei-Dong lin Hui-Yi LIU shu-Yu JIN Xing-Dong YE Yan-lin CHEN Si-Jia PU Yang LIU Shang-Fei HE shu-lin WU Hai DENG Yu-mei XUE Department of Cardiology Guangdong Cardiovascular InstituteGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhouChina The Second School of Clinical Medicine Southern Medical UniversityGuangzhouChina School of Medicine South China University of TechnologyGuangzhouChina Department of Cardiology the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouChina Guangdong Provincial Key Laboratory of Clinical Pharmacology Research Center of Medical SciencesGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhouChina Qinghai Province Cardio Cerebrovascular Disease Specialist Hospital XiningChina

BACKGROUND Epidemiological surveys on heart failure(HF)in Chinese community are relatively *** study aimed to estimate the prevalence and incidence of HF among community residents in southern *** Baseline data of this prospective study was collected from 2015 to 2017 among 12,013 permanent residents aged≥35years in Guangzhou,*** same survey process was carried out for individuals aged≥65 years after a three-year *** The overall prevalence of HF in community residents aged≥35 years was 1.06%.Male had significantly higher risk of HF prevalence[odds ratio(OR)=1.50,P=0.027].The gender-adjusted risk of HF was 1.48 times higher per 10 years *** prevalence was statistically associated with atrial fibrillation,valvular heart disease,hypertension and chronic obstructive pulmonary disease after adjusting for age and gender(OR=8.30,5.17,1.11,2.28,respectively;all P<0.05).HF incidence in individuals aged≥65 years were 847 per 100,000 *** atrial fibrillation,valvular heart disease,and diabetes mellitus were risk factors for HF incidence for individuals aged≥65 years adjusting for age and gender(OR=5.05,3.99,2.11,respectively;all P<0.05).Besides,residents with new-onset atrial fibrillation and myocardial infarction were at significantly higher risk of progression to HF(OR=14.41,8.54,respectively;all P<0.05).CONCLUSIONS Both pre-existing and new-onset cardiovascular diseases were associated with HF incidence in southern *** of related cardiovascular diseases may be helpful to reduce the incidence of HF.

关键词： prevalence cardiovascular incidence

Longitudinal dynamics from hydrodynamics with an order parameter

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Chinese Physics C 2021年第4期45卷 265-272页

作者： shu lin Gezheng Zhou School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China

We studied coupled dynamics of hydrodynamic fields and order parameter in the presence of nontrivial longitudinal flow using the chiral fluid dynamics *** found that longitudinal expansion provides an effective relaxation for the order parameter,which equilibrates in an oscillatory *** oscillations are also visible in hydrodynamic degrees of freedom through coupled *** oscillations are reduced when dissipation is *** also found that the quark density,which initially peaked at the boundary of the boost invariant region,evolves toward forward rapidity with the peak velocity correlated with the velocity of longitudinal *** peak broadens during this *** corresponding chemical potential rises due to simultaneous decrease of density and *** compared the cases with and without dissipation for the order parameter and also the standard hydrodynamics without order *** found that the corresponding effects on temperature and chemical potential can be understood from the conservation laws and different speeds of equilibration of the order parameter in the three cases.

关键词： relativistic hydrodynamics linear sigma model chiral phase transition heavy ion collisions equilibration

Phase-dependent lithium-alloying reactions for lithium-metal batteries

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Chinese Chemical Letters 2024年第4期35卷 1-2页

作者： shu lin Kezhen Qi College of Pharmacy Dali UniversityDali 671000China

With the increasing demand for higher energy lithium-ion batteries (LIBs), it is imperative to develop high-capacity electrode materials [1–4]. Due to the unique electrochemical Li-alloying reactions, Li-alloys offer high theoretical capacity, especially lithiumrich phase alloys, which exceeds the theoretical capacity of graphite anodes [5–7]. Phase-transition, which significantly influences lithium alloy reactions, determines high voltage hysteresis,low Coulombic efficiency (CE), and short cycling life [8,9].

关键词： alloying alloys cycling