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Preparation of Sulphur-containing Aromatic Amines by Reduction of the Corresponding Aromatic Nitro Compounds with Hydrazine Hydrate over Iron Oxide Hydroxide Catalyst

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Chinese Chemical Letters 2006年第8期17卷 1045-1047页

作者： Qi Xun SHI Rong wen LU Zhu Xia ZHANG de Feng zhao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Sulphur-containing aromatic nitro compounds were rapidly reduced to the corresponding amines in high yields by employing hydrazine hydrate as a hydrogen donor in the presence of iron oxide hydroxide catalyst. It was worth noting that the catalyst exhibited extremely high activity. The reduction could be completed within 20-50 min and the yields were up to 97-99 %.

关键词： Iron oxide hydroxide catalyst hydrazine hydrate sulphur-containing aromatic nitro compounds reduction.

Reduction of Sulphur-containing Aromatic Nitro Compounds with Hydrazine Hydrate over Iron(III) Oxide-MgO Catalyst

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Chinese Chemical Letters 2006年第4期17卷 441-443页

作者： Qi Xun SHI Rong wen LU Zhu Xia ZHANG de Feng zhao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron（Ⅲ） oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.

关键词： Iron(Ⅲ) oxide-MgO catalyst hydrazine hydrate sulphur-containing aromatic nitro compounds reduction.

Limit Analysis of defect-Free Pipe Elbow Under Internal Pressure With Mean Yield Criterion

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Journal of Iron and Steel Research International 2013年第4期20卷 11-15页

作者： ZHANG Shun-hu GAO Cai-ru zhao de-wen WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University

With mean yield（MY）criterion,an analytical solution of the collapse load for a defect-free pipe elbow under internal pressure is first *** is a function of ratio of thickness to radius t0/r0,strain hardening exponent n,curvature influence factor mand ultimate tensile *** collapse load increases with the increase of m,and it is the same as the burst pressure of straight pipe if m=1is *** MY-based solution is compared with those based on Tresca,Mises and twin shear stress（TSS）yield criteria,and the comparison indicates that Tresca and twin shear stress yield criteria predict a lower bound and an upper bound to the collapse load ***,the MY-based solution lies just between the TSS and Tresca solutions,and almost has the same precision with the Mises solution.

关键词： limit analysis pipe elbow internal pressure strain hardening exponent MY criterion

A novel approach for radionuclide diffusion in the enclosed environment of a marine nuclear reactor during a severe accident

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Nuclear Science and Techniques 2022年第2期33卷 53-65页

作者： Fang zhao Shu-Liang Zou Shou-Long Xu Xuan Wang Jun-Long Wang de-wen Tang School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China Hunan Provincial Key Laboratory of Emergency Safety Technology and Equipment for Nuclear Facilities Hengyang 421001China Shanghai Nuclear Engineering Research and design Institute Co.LTD Shanghai 200000China Science and Technology On Reactor System design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

A severe accident in a marine nuclear reactor leads to radionuclide leakage,which causes hidden dangers to workers and has adverse effects of environmental *** is necessary to propose a novel approach to radionuclide diffusion in a confined environment after a severe accident in a marine nuclear ***,this study proposes a new method for the severe accident analysis program MELCOR coupled with computational fluid dynamics scSTREAM to study radioactive diffusion in severe *** radionuclide release fraction and temperature calculated by MELCOR were combined with the scSTREAM calculations to study the radionuclide diffusion behavior and the phenomenon of radionuclide diffusion in different space environments of the reactor under the conditions of varying wind velocities of the ventilation system and diffusion *** results show that the wind velocity of the ventilation system is very small or zero,and the turbulent diffusion of radionuclides is not obvious and diffuses slowly in the form of condensation sedimentation and gravity *** the wind speed of the ventilation system increases,the flow of radionuclides meets the wall and forms eddy currents,affecting the time variation of radionuclides diffusing into chamber *** wind velocity of the ventilation system and the diffusion speed has opposite effects on the time variation trend of radionuclide diffusion into the four chambers.

关键词： Radionuclide diffusion MELCOR coupled with scSTREAM Severe accident Marine nuclear reactor

Electromagnetic Ion Beam Instability in the Solar Corona

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Research in Astronomy and Astrophysics 2024年第2期24卷 171-179页

作者： wen Liu Jin-Song zhao de-Jin Wu Huan-Yu Jia Si-Ming Liu School of Mechanics and Aeronautics Southwest Jiaotong UniversityChengdu 610000China School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610000China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China

Remote-sensing measurements indicate that heavy ions in the corona undergo an anisotropic and mass-charge dependent energization.A popular explanation to this phenomenon is the damping of the Alfven/ion cyclotron *** this paper,we propose that the ion beam instability can be an important source of the Alfven/ion cyclotron waves,and we study the excitation of the ion beam instability in the corona at the heliocentric distance~3R_(⊙)and the corresponding energy transfer process therein ba sed on plasma kinetic *** results indicate that the existence of the motionless heavy ions inhibits the ion beam ***,the anisotropic beams of heavy ions promote the excitation of the ion beam ***,the existence ofαbeams can provide a second energy source for exciting beam ***,when both the proton beam and the a beam reach the instability excitation threshold,the proton beam driven instability excites ***,the excitation threshold of the Alfven/ion cyclotron instability driven by ion beam is of the local Alfven speed or even less in the corona.

关键词： plasmas-instabilities-waves-Sun corona

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing Xue Yuejia Ma Ke Ye Xue zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang Qing Xia department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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Neural Regeneration Research 2025年第8期20卷 2361-2372页

作者： Shengyang Zhou Ting Li Wei Zhang Jian Wu Hui Hong Wei Quan Xinyu Qiao Chun Cui Chenmeng Qiao Weijiang zhao Yanqin Shen Laboratory of Neurodegenerative and Neuroinjury Diseases Wuxi Medicine SchoolJiangnan UniversityWuxiJiangsu ProvinceChina

Interferon regulatory factor 7 plays a crucial role in the innate immune ***,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains *** we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial *** the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 *** addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and *** together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

关键词： cyclic guanosine monophosphate adenosine monophosphate synthase H151 interferon regulatory factor 7 M1 phenotype neurodegenerative disease neuroinflammation Parkinson’s disease RU521 STING type I interferon

Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke:a special outlook on mitochondrial delivery

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Neural Regeneration Research 2025年第8期20卷 2181-2198页

作者： Jiali Chen Yiyang Li Xingping Quan Jinfen Chen Yan Han Li Yang Manfei Zhou Greta Seng Peng Mok Ruibing Wang Yonghua zhao Institute of Chinese Medical Sciences State Key Laboratory of Quality Research in Chinese MedicineUniversity of MacaoTaipaMacao Special Administrative RegionChina department of Pharmacy Hunan Provincial People’s Hospitalthe First Affiliated Hospital of Hunan Normal UniversityChangshaHunan ProvinceChina department of Electrical and Computer Engineering University of MacaoTaipaMacao Special Administrative RegionChina department of Pharmaceutical Sciences Faculty of Health SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina

Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on *** vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic ***,the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery *** utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles,their delivery efficacy may be greatly ***,previous studies have indicated that microvesicles,a subset of large-sized extracellular vesicles,can transport mitochondria to neighboring cells,thereby aiding in the restoration of mitochondrial function post-ischemic *** extracellular vesicles have also demonstrated the capability to transfer mitochondrial components,such as proteins or deoxyribonucleic acid,or their sub-components,for extracellular vesicle-based ischemic stroke *** this review,we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification *** the complex facets of treating ischemic stroke,we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment ***,given the burgeoning interest in mitochondrial delivery,we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy.

关键词： delivery engineering extracellular vesicles identification ischemic stroke isolation mitochondria targeting strategy therapeutic effects

Subnetwork-based federated few-shot semantic segmentation of organ images

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Optoelectronics Letters 2025年

作者： Wu Junpeng zhao Meng Zhang Huanping Key Laboratory of Computer Vision and System of Ministry of Education， School of Computer Science and Engineering， Tianjin University of Technology

Federated learning(FL)， as a distributed learning paradigm， allows multiple medical institutions to collaborate on learning without the need to centralize all client data. However， existing methods pay little attention to more challenging medical image semantic segmentation tasks， especially in the scenario of the imbalanced dataset in federated few-shot learning. In this paper， we propose a subnetwork-based federated few-shot organ image segmentation method. Firstly， individual clients train using local training samples and then upload local model gradients to the server. The server utilizes their respective local model gradients to update the subnetwork maintained on the server and generate aggregation weights for forming personalized model parameters. Through this method， we can learn the similarities between different clients to address data heterogeneity issues. In addition， to enhance the communication efficiency between clients and the server， we have also designed a personalized layer aggregation strategy， which only transmits partial layer model parameters during the communication process to improve communication efficiency. Finally， we conducted experiments on ABD-MRI and ABD-CT datasets to demonstrate the effectiveness of our method.

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