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Structure-Activity Correlations of Calcined Mg-Al Hydrocalcites for Aliphatic Polycarbonate Synthesis via Transesterification Process

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Chinese Journal of Polymer Science 2017年第1期35卷 130-140页

作者： zi-qing wang Yuan-sheng Bai Wei Jiang Xian-gui Yang Shao-ying Liu 王公应 Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Changzhou Institute of Chemistry Changzhou 213164 China

Mg-A1 mixed oxides with different Mg/A1 molar ratio were prepared by thermal decomposition of hydrotalcite- like precursors at 500 ℃ for 5.0 h and used as catalysts for the transesterification of diphenyl carbonate with 1,4-butanediol to synthesize high-molecular-weight poly（butylene carbonate）（PBC）. The structure-activity correlations of these catalysts in this transesterification process were discussed by means of various characterization techniques. It was found that the chain growth for the formation of PBC can only be obtained through connecting -OH and -OC（C）OC6H5 end-group upon removing the generated phenol, and the sample with Mg/A1 molar ratio of 4.0 exhibited the best catalytic performance, giving PBC with Mw of 1.64 × 105 g/mol at 210℃ for 3.0 h. This excellent activity depended mainly on the specific surface area and basicity rather than pore structure or crystallite size of MgO.

关键词： Mg-A1 hydrotalcite Poly(butylene carbonate) Diphenyl carbonate Transesterification Basic sites

Efficiency of collective myosin Ⅱ motors studied with an elastic coupling power-stroke ratchet model

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Chinese Physics B 2018年第12期27卷 559-562页

作者： zi-qing wang Jin-Fang Li Ying-Ge Xie Guo-Dong wang Yao-Gen Shu College of Science Northwest A & F University CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences (CAS)

We proposed a modified ratchet model including power-stroke and elastic coupling to study the efficiency of collective non-processive motors such as myosin Ⅱ in muscle. Our theoretical results are in good agreement with the experimental data. Our study not only reveals that the maximum efficiency depends on elasticity and is independent of transition rates but also indicates that the parameters fitted to fast muscle are different from those fitted to a slow one. The latter may imply that the structure of the fast muscle is different from that of the slow one. The main reason that our model succeeds is that velocity in this model is an independent variable.

关键词： efficiency of collective non-processive motors ratchet model power-stroke elasticity

Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo zi-Ang Nan qing Li Xiufang Li zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing wang Wei wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun wang qing Shi Guofan Zhang Yuxuan Zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： zi Ye Runqing Liu Hangxing wang Aizhen Zuo Cen Jin Nan wang Huiqi Sun Luqian Feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia Yu wang Chun Cheng Yang qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG Tian MAO Jin-Song wang Xiu-qing HU Xiao-Xin ZHANG Liping FU Nan JIA Tianfang wang National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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聚乙烯吡咯烷酮固载卤化锌催化酯交换法合成脂肪族聚碳酸酯

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高分子学报 2016年第12期26卷 1654-1661页

作者：王自庆杨先贵刘绍英胡静王公应中国科学院成都有机化学研究所成都610041 中国科学院大学北京100049 常州化学研究所常州213164

以聚乙烯吡咯烷酮(PVP)和卤化锌ZnX2(X=Cl、Br和I)反应制备了一系列PVP固载的ZnX2催化剂ZnX2(PVP),用于催化碳酸二苯酯(DPC)和脂肪族二元醇熔融酯交换反应合成高分子量脂肪族聚碳酸酯(APCs).以TGA、FTIR和XPS为表征手段对催化剂结构与... 详细信息

以聚乙烯吡咯烷酮(PVP)和卤化锌ZnX2(X=Cl、Br和I)反应制备了一系列PVP固载的ZnX2催化剂ZnX2(PVP),用于催化碳酸二苯酯(DPC)和脂肪族二元醇熔融酯交换反应合成高分子量脂肪族聚碳酸酯(APCs).以TGA、FTIR和XPS为表征手段对催化剂结构与性能间的构效关系进行了研究.研究发现,催化剂Lewis酸强度的增强对聚合和分解反应均有明显的促进作用,Zn^(2+)空间位阻的增大则可以降低酯交换反应的剧烈程度,同时还可以有效抑制副反应的进行.与纯ZnBr2相比,ZnBr2(PVP)高温催化性能更优,在最佳工艺条件下合成PBC聚合物的数均分子量Mn可以达到1.59×105,对应收率和PDI值分别为84.5%和1.79.该催化剂的优异性能主要归结于PVP与Zn^(2+)相互作用的存在,可为酯交换反应的进行提供适当Lewis酸性和空间位阻.

关键词：卤化锌聚乙烯吡咯烷酮脂肪族聚碳酸酯碳酸二苯酯熔融酯交换

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： qing He Zhen wang Yuchen wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming