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Effects of Calcination Temperature on the Acidity and Catalytic Performances of HZSM-5 Zeolite Catalysts for the Catalytic Cracking of n-Butane

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Journal of Natural Gas Chemistry 2005年第4期14卷 213-220页

作者： Jiangyin lu zhen zhao Chunming Xu Aijun Duan Pu Zhang State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

The acidic modulations of a series of HZSM-5 catalysts were successfully made by calcination at different treatment temperatures, i.e. 500, 600, 650, 700 and 800 ℃, respectively. The results indicated that the total acid amounts, their density and the amount of B-type acid of HZSM-5 catalysts rapidly decreased, while the amounts of L-type acid had almost no change and thus the ratio of L/B was obviously enhanced with the increase of calcination temperature （excluding 800 ℃）. The catalytic performances of modified HZSM-5 catalysts for the cracking of n-butane were also investigated. The main properties of these catalysts were characterized by means of XRD, N2 adsorption at low temperature, NH3-TPD, FTIR of pyridine adsorption and BET surface area measurements. The results showed that HZSM-5 zeolite pretreated at 800 ℃ had very low catalytic activity for n-butane cracking. In the calcination temperature range of 500-700 ℃, the total selectivity to olefins, propylene and butene were increased with the increase of calcination temperature, while, the selectivity for arene decreased with the calcination temperature. The HZSM-5 zeolite calcined at 700 ℃ produced light olefins with high yield, at the reaction temperature of 650 ℃ the yields of total olefins and ethylene were 52.8% and 29.4%, respectively. Besides, the more important role is that high calcination temperature treatment improved the duration stability of HZSM-5 zeolites. The effect of calcination temperature on the physico-chemical properties and catalytic performance of HZSM-5 for cracking of n-butane was explored. It was found that the calcination temperature had large effects on the surface area, crystallinity and acid properties of HZSM-5 catalyst, which further affected the catalytic performance for n-butane cracking.

关键词： HZSM-5 zeolite catalyst acidic modification calcination temperature n-butane catalytic cracking olefin

An automatic phase-matching technique of CYCIAE-100 cyclotron

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Nuclear Science and Techniques 2017年第9期28卷 25-30页

作者： Xiao-Liang Fu Zhi-Guo Yin Bin Ji zhen-lu zhao Jun-Yi Wei Tian-Jue Zhang China Institute of Atomic Energy Beijing 102413 China

The RF system of CYCIAE-100 cyclotron has two cavities, which are driven separately by two identical 100-k W RF amplifiers. Due to the power on sequence issue of the three DDSs in the LLRF systems, each time when the system is individually switched on, the phase relationship may not satisfy the requirements of beam acceleration. Instead of adding an extra reset logic to the system, a search and validation algorithm based on the decision tree has been carried out to make sure the phase of the two cavities is correct right after applying power to the cavities, taking advantage of existing hardware resources. In the first year of operation, there are more than 20 times of scheduled shutdown of the cyclotron system. For each time when the cyclotron RF system is completely shutdown and powered on again, the operator confirmed that the phase matching of the two cavities can be done automatically within 30 s. The related work, including the optimization of the phase detector and the development and validation of the algorithm, is reported in this paper.

关键词：回旋加速器相位关系匹配技术射频系统验证算法射频放大器相位检测器 DDSS

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： Jia zhao Taixi Feng Guimin lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

有关护士全面质量管理知识掌握程度的调查分析

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实用护理杂志 2003年第12期19卷 56-57页

作者：谢文张振路徐朝艳中山大学附属第一医院护理部

目的了解不同职称护士全面质量管理知识的掌握程度.方法采用问卷法随机调查198位护士.结果护士对护理质量管理知识的掌握程度因职称、护龄的不同而不同,与学历无关.结论护士护理质量管理知识掌握程度受职称、护龄的影响,应从以下几方面... 详细信息

目的了解不同职称护士全面质量管理知识的掌握程度.方法采用问卷法随机调查198位护士.结果护士对护理质量管理知识的掌握程度因职称、护龄的不同而不同,与学历无关.结论护士护理质量管理知识掌握程度受职称、护龄的影响,应从以下几方面加强TQC的教育:(1)重视低层次护士的培养;(2)强化高年资护士管理意识;(3)丰富继续教育形式,加强各级人员培训.

关键词：全面质量管理护理管理护士

Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases

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Neural Regeneration Research 2025年第8期20卷 2373-2381页

作者： Lifang zhao Mingkai Zhang Qimeng Li Xuemin Wang Jie lu Ying Han Yanning Cai Department of Clinical Biobank Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Geriatric Medical Research Center BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology and Nuclear Medicine Xuanwu HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics BeijingChina Key Laboratory of Neurodegenerative diseases Ministry of EducationBeijingChina School of Biomedical Engineering Hainan UniversityHaikouHainan ProvinceChina Center of Alzheimer’s Disease Beijing Institute for Brain DisordersBeijingChina National Clinical Research Center for Geriatric Diseases BeijingChina Institute of Biomedical Engineering Shenzhen Bay LaboratoryGaoke Innovation CenterShenzhenGuangdong ProvinceChina Department of Neurobiology Xuanwu HospitalCapital Medical UniversityBeijingChina

Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative ***,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°*** aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large *** samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline *** samples were stored at-80°C for up to 6 years before being used in this *** results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage ***,the level of total tau showed a negative correlation with sample storage ***,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage *** was not observed in individuals with cognitive ***,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage ***,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's ***,in cohort studies,it is important to consider the impact of storage time on the overall results.

关键词： Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein neurodegeneration neurofilament light chain plasma biomarkers single molecule array storage time tau

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao Liang Xingping Quan Xiaorui Geng Yujing Huang Yonghua zhao Lei Xi zhen Yuan Ping Wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing Zhang Lanfang Li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu Kai zhao Guoqiang Liu Youming lu Xinyan Li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Unlocking the stable interface in aqueous zinc-ion battery with multifunctional xylose-based electrolyte additives

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Journal of Energy Chemistry 2025年第1期100卷 770-778页

作者： Xiaoqin Li Jian Xiang lu Qiu Xiaohan Chen Yinkun zhao Yujue Wang Qu Yue Taotao Gao Wenlong Liu Dan Xiao zhaoyu Jin Panpan Li Institute for Advanced Study Chengdu University School of Mechanical Engineering Chengdu University College of Food and Biological Engineering Chengdu University Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China College of Materials Science and Engineering Sichuan University

The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries（AZIBs）. These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose（Xylo） molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn2+ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.

关键词： Solvation

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying lu Linqiang Tian Sanqiao Yao Feng Lai Yangfan Liang Chuanchuan Liu Yujia lu Sijia Tian Yanmei zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells