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Kinetics and mechanism of the adsorption of methylene blue onto ACFs

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Journal of China University of Mining and Technology 2008年第3期18卷 437-440页

作者： yang Zhi-yuan Department of Chemistry ＆ Chemical Engineering Xi ＇an University of Science and Technology Xi＇an Shaanxi 710054 China Geology Institute Xi＇ an Branch of China Coal Research Institute Xi＇ an Shaanxi 710054 China

The kinetics and mechanism of methylene blue (MB) adsorption onto activated carbon fibers (ACFs) have been studied. The effects of various experimental parameters, such as the initial MB concentration and the ACF mass, on the adsorption rate were investigated. Equilibrium data were fit well by a Freundlich isotherm equation. Adsorption measurements show that the process is very fast. The adsorption data were modeled using first- and second-order kinetic equations and intra–particle diffusion models. It was found that the first-order kinetic equation could best describe the adsorption kinetics. The adsorption process was found to be complex and controlled by both surface and pore diffusion with surface diffusion at the earlier stages, followed by pore diffusion at the later stages. The thermodynamic parameters △G0, △S0 and △H0, have been calculated. The thermodynamics of the MB-ACF system indicate that the adsorption process is spontaneous.

关键词： sorption ACFs methylene blue equilibrium mechanism

The role of light in regulating seed dormancy and germination^FA

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Journal of Integrative Plant Biology 2020年第9期62卷 1310-1326页

作者： Liwen yang Shuangrong Liu Rongcheng Lin Key Laboratory of Photobiology Institute of Botanythe Chinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excel ence in Molecular Plant Sciences the Chinese Academy of SciencesBeijing 100093China

Seed dormancy is an adaptive trait in plants. Breaking seed dormancy determines the timing of ger-mination and is, thereby essential for ensuring plant sur-vival and agricultural production. Seed dormancy and the subsequent germination are controlled by both internal cues (mainly hormones) and environmental signals. In the past few years, the roles of plant hormones in regulating seed dormancy and germination have been uncovered. However, we are only beginning to understand how light signaling pathways modulate seed dormancy and inter-action with endogenous hormones. In this review, we summarize current views of the molecular mechanisms by which light controls the induction, maintenance and re-lease of seed dormancy, as well as seed germination, by regulating hormone metabolism and signaling pathways.

关键词： light germination metabolism

Recent progress and challenges in the treatment of spinal cord injury

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Protein & Cell 2023年第9期14卷 635-652页

作者： Ting Tian Sensen Zhang Maojun yang Ministry of Education Key Laboratory of Protein Science Beijing Advanced Innovation Center for Structural BiologyBeijing Frontier Research Center for Biological StructureSchool of Life SciencesTsinghua UniversityBeijing100084China Cryo-EMFacilityCenter SouthernUniversityof ScienceandTechnologyShenzhen518055China

Spinal cord injury(SCI)disrupts the structural and functional connectivity between the higher center and the spinal cord,resulting in severe motor,sensory,and autonomic dysfunction with a variety of *** pathophysiology of sci is complicated and multifaceted,and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after *** strategies targeting multiple aspects of scI pathology have achieved greater beneficial effects than individuai therapy *** many problems and challenges remain,the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat *** this review,we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following scI at both the acute and chronic *** addition,we analyze the current status,remaining problems,and realistic challenges towards clinical ***,we consider the future of scI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical *** forward,clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeuticbenefitinhumanswithscl.

关键词： spinal cord injury axon regeneration functional recovery therapeutic strategies clinical translation

Efficient anion immobilization enabled by structurally controllable halloysite for dendrite-free sodium metal anode

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Science China Chemistry 2023年第9期66卷 2600-2611页

作者： Caihong yang Yicheng Hua Ying Zhang Jie wang Huanwen wang Liangjie Fu Aidong Tang Huaming yang Engineering Research Center of Nano-Geomaterials of Ministry of Education China University of GeosciencesWuhan 430074China Laboratory of Advanced Mineral Materials China University of GeosciencesWuhan 430074China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Hunan Key Laboratory of Mineral Materials and Application School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China

Sodium metal has shown great potential as an inexpensive anode for rechargeable batteries. However, the growth of sodium dendrites continues to hinder the commercialization of Na metal batteries. Herein, an effective strategy using anion-anchoring halloysite nanotube(HNT) coating was proven to prevent the diffusion of anions and trigger uniform Na deposition. Through theoretical calculation, a model of active site of fixed anions exposed from HNTs after acid activation was established for the first time, revealing that Si–Al sites are effective active site of acid-activated HNTs. Furthermore, HNTs with strong and effective adsorption capacity for anions were obtained by controlling the structure of HNTs to regulate the exposure of Si–Al sites. The strong interaction between sites of acid-activated HNTs and the SO_(3)CF_(3)^(-) anion effectively promotes the dissociation of sodium salts, the release of Na^(+) and subsequent migration. As a result, HNTs acid activation for 4 h shows a steady sodium deposition process and displays high Coulombic efficiency in half cell, long cycle life in symmetric cell and full cell. This work provides a basic theoretical basis for the design of nanoclay with abundant and effective active site to fix anions for dendritic free metal batteries.

关键词： halloysite anion immobilization ion transport sodium dendrites sodium metal batteries

Recent progresses on the development of thioxo-naphthalimides

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Chinese Chemical Letters 2020年第11期31卷 2877-2883页

作者： Xiao Luo Youjun yang Xuhong Qian School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China State Key Laboratory of Bioreactor Engineering School of PharmacyEast China University of Science and TechnologyShanghai 200237China

Thioxo/dithioxo-naphthalimide is a class of rarely visited fluorophore,first synthesized in *** chemistry was devised to achieve mono or dual thionation of the two carbonyl groups of 1,*** effectively shifts absorption maximum to longer spectral wavelength,significantly increase absorption coefficients,and dramatically enhances intersystem crossing efficiency with respect to their *** were first explored as potent photocleavers to induce DNA strand break and novel photosensitizers for photodynamic *** recent years,the unique chemistry of thioxo groups has been harnessed to achieve new applications,such as fluorescent sensors for heave metal *** unique photochemical and photophysical characteristics revitalize them intriguing functional molecules to *** this short review,we wish to revisit their first discovery,facile synthesis,and the endeavors on the use of thioxo/dithioxo-naphthalimides for novel chemical and biomedical applications.

关键词： Thioxo-naphthalimide Intersystem crossing Photocleaver Photosensitizer Fluorescent sensor

Solubility and solution thermodynamics of ammonium dihydrogen phosphate in the water–methanol system

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2518-2525页

作者： Dejun Xu Dehua Xu Yanjun Zhong Tao Luo Xiushan yang Zhiye Zhang Lin yang Xinlong wang School of Chemical Engineering Sichuan UniversityChengdu 610065China

The solubility of ammonium dihydrogen phosphate(MAP)in the water–methanol system is essential for antisolvent crystallization *** investigate the effect of methanol on the solubility of MAP in water,the solubility of MAP in the water–methanol system was determined by dynamic method and static equilibrium method at temperatures ranging from 293.2 to 343.2 K at atmospheric *** showed that the solubility of MAP increased with the increase of temperature and the increase of water mole fraction in the water–methanol *** experimental solubility data were correlated with the modified Apelblat equation,the combined nearly ideal binary solvent/Redlich–Kister(CNIBS/R–K)model and the Jouyban–Acree *** calculated results based on these three models were in very good agreement with the experimental data with the average relative deviations of 0.65%,0.97%,and 5.38%,***,the thermodynamic properties of the MAP dissolution process in the water–methanol system,including Gibbs energy change,enthalpy,and entropy were obtained by the Van’t Hoff equation,which can be used to assess the crystallization process.

关键词： Ammonium dihydrogen phosphate Solubility water–methanol system

Physicochemical analysis of individual atmospheric fine particles based on effective surface-enhanced Raman spectroscopy

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Journal of Environmental Sciences 2019年第1期31卷 388-395页

作者： Zhenli Sun Fengkui Duan Kebin He Jingjing Du Liu yang Hui Li Tao Ma Shuo yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Fine particles associated with haze pollution threaten the health of more than 400 million people in China. It is therefore of great importance to thoroughly investigate and understand their composition. To determine the physicochemical properties in atmospheric fine particles at the micrometer level, we described a sensitive and feasible surface-enhanced Raman scattering(SERS) method using Ag foil as a substrate. This novel method enhanced the Raman signal intensities up to 10,000 a.u. for ν(NO_3^-) in fine *** SERS effect of Ag foil was further studied experimentally and theoretically and found to have an enhancement factor of the order of ～10~4. Size-fractionated real particle samples with aerodynamic diameters of 0.4–2.5 μm were successfully collected on a heavy haze day,allowing ready observation of morphology and identification of chemical components, such as soot, nitrates, and sulfates. These results suggest that the Ag-foil-based SERS technique can be effectively used to determine the microscopic characteristics of individual fine particles, which will help to understand haze formation mechanisms and formulate governance policies.

关键词： SERS PM2.5 Individual particle Atmospheric

Oil-water Separation Performance of Electrospray Reduced Graphene Oxide Microspheres with a Local Radially Aligned and Porous Structure

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Chemical Research in Chinese Universities 2021年第3期37卷 528-534页

作者： YU Ruomeng SHI Yongzheng yang Dongzhi Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P.R.China

Micro-size oil adsorbents are effective for the rapid remediation of special oil ***,N-doped reduced graphene oxide(RGO)microspheres(ca.150µm in diameter)with a local radially aligned and porous structure are fabricated by combining electrospray-freeze-drying with thermal treatment for rapid separation of *** to its hydrophobic/oleophilic properties and oriented structure,the N-doped RGO microspheres achieve high capacities and fast adsorption rates for a variety of oils and organic ***,excellent oil-water separation performance on floating oil/oil-water emulsions and stable cyclic adsorption capacities are obtained for the local radially aligned and porous ***,N-doped RGO microspheres with the unique porous structure have the potential for the remediation of oily sewage and oil spills.

关键词： Electrospray Radially aligned structure Microsphere Reduced graphene oxide Oil-water separation

Coseismic Coulomb stress changes induced by a 2020-2021 M_(w)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface

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Geodesy and Geodynamics 2024年第1期15卷 1-12页

作者： Lei yang Jianjun wang Caijun Xu School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Collaborative Innovation Center of Geospatial Technology Wuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan 430079China

Three M_(w)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(w)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(w)8.2 Chignik thrust earthquake on July 29,*** spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among *** we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction *** results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,*** Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%*** factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench.

关键词： The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap