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The Mechanism of Sol-Gel Synthesis of Normal Spinel LiMn_2O_4 with Chelation of Citric Acid

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Journal of Wuhan University of Technology(Materials Science) 2002年第4期17卷 21-24页

作者：巫辉 School of Science Wuhan University of Technology Wuhan China

The sol-gel process of citric acid chelating with metal cations for the synthesis of normal spinel LiMn 2O 4 and the reaction mechanism were investigated by means of XRD,IR,TG-DTA, and *** results show that at the beginning lithium citrate and chelate compound of citric acid with manganese ions formed,and then with heating the esterification and condensation reactions occured between them and *** products obtained are polymers in which metal cations are distributed homogeneously on atomic scale that ensure high reactivity to cations of Li + and Mn 2+.Firing the gel prepared by this process,the lattice diffusions of solid reactant ions caused by non-homogeneity of reactants are eliminated and *** 400℃ phase-pure LiMn 2O 4 with nanometer scale crystallization having precise stoichiometry and perfect crystallization can be *** model of chelate coordinate of double-molecule between citric acid and Mn 2+ in the gel network is *** is important for explaining the dispersion state of Mn 2+ and the formation process of gel by this model.

关键词： sol-gel process chelation of citric acid LiMn 2O 4 mechanism of reaction

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong sun Wenwen Guan Cailing chen Chao Wu xiaoling Liu Biao Meng Tao chen Yu Han Jun Wang Shibo xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan Pu Yongmin chen Ke Lei Yujie Duan Linjiao Mao Xuhui Zeng xi Luo Yuntao Zhang Yuqin Dong Jin Zhong Zhang Yan sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

Endometrial Mucin-1 and Pinopode in Peri-implantation Phase in Ovarian High Responders during Controlled Ovarian Hyperstimulation Cycles

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Journal of Reproduction and Contraception 2007年第3期18卷 187-196页

作者： Qiu-ju chen xiao-xi sun Lu LI xiao-hong GAO Yu WU Li-nan chenG Department of Reproductive Medicine International Peace Maternity and Child Health Hospital Shanghai200030 China

Objective To investigate effects of ovarian high response on endometrial mucin-1 （MUC1） and pinopode in peri-implantation phase in controlled ovarian hyperstimulation （COH） cycles. Methods Ovarian high response was defined as serum E2 〉 15 000 pmol/L on the day of hCG administration in COH cycle using GnRH agonist and recombinant FSH （n=8）. Healthy and fertile women were used as the natural control （n=10）. Endometrial biopsies were performed on the day of LH＋ 7/hCG＋ 7. Pinopode formation was observed by scanning electron microscope. Expression of MUC1 was detected with quantitative Real-time PCR and immunohistochemistry. Results In high response group, the lumen surface was covered with variant pinopodes and microvillous. The expression of MUC1 mRNA in high response group was lower than that in the natural control （P〈0.05）. Immunostaining for MUC1 protein in glandular and luminal epithelium in high response group was lower than that in the natural control （P〈0. 05）. Conclusion Asynchronized pinopode appearance and lower expression of MUC1 during peri-implantation period were the characteristics of endometrium in high response group, Which may provide a clue of decreased endometrial receptivity in the supraphysiological hormone milieu.

关键词： endometrium controlled ovarian hyperstimulation high response mucin-1 pinopode

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： xihang chen Zhifeng chen Menghua Li Weiwei Guo Shuolong Yuan Liangwei Xu Chang Lin xi Shi Wei chen Shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： xia JIANG Yanyan FANG xianlin ZENG Jian sun Jie chen National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 1-19页

作者： Shuo chen Shengpeng Su Yanfang Huang Bingbing Liu Hu sun Shuzhen Yang Guihong Han School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Henan ProvinceZhengzhou 450001China

Solvent extraction,a separation and purification technology,is crucial in critical metal *** solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental *** solvents have been recognized as potential alternatives to these harmful organic *** the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low *** this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically ***,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively ***,future opportunities and challenges of DESs were explored in the current research *** conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.

关键词： deep eutectic solvents preparations properties separation and purification critical metal metallurgy

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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Nano-Micro Letters 2025年第3期17卷 340-354页

作者： Li An Jianyi Li Yuanmiao sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian xi * Zhichuan JXu Chun‑Hua Yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is *** substituting Fe content influences both current change tendency and surface reconstruction ***_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based ***,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

近红外光谱主成分分析与模糊聚类的典型地面目标物识别

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光谱学与光谱分析 2017年第11期37卷 3386-3390页

作者：李晨曦孙哲蒋景英刘蓉陈文亮徐可欣天津大学精密测试技术及仪器国家重点实验室天津300072 天津大学精密仪器与光电子工程学院天津300072

近红外光谱技术在遥感监测领域中应用广泛,针对典型地面目标物遥感监测识别需要,提出了光谱主成分分析(PCA)与模糊聚类结合的分类识别方法,提高了识别算法效率及准确性。以四类典型地面目标物作为研究对象,分别测量其在1 100~2 500nm范... 详细信息

近红外光谱技术在遥感监测领域中应用广泛,针对典型地面目标物遥感监测识别需要,提出了光谱主成分分析(PCA)与模糊聚类结合的分类识别方法,提高了识别算法效率及准确性。以四类典型地面目标物作为研究对象,分别测量其在1 100~2 500nm范围内漫反射光谱,首先对漫反射光谱进行主成分分析,得到代表光谱特征的主成分分量,然后将其作为模糊聚类分析模型输入参数,计算样品主成分集合之间贴合度,最后利用择近原则对样品进行匹配分类。结果表明,主成分分析可以有效提取光谱特征并且降低数据维度,结合基于择近原则的模糊分类方法,可有效提高算法准确性与效率,为遥感光谱在地面目标物识别应用提供了有益的参考。

关键词：近红外光谱主成分分析模糊聚类