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Theoretical Investigation on the Abstraction Reaction of H with (CH_3)_3SiH

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Chemical Research in Chinese Universities 2002年第1期18卷 47-51页

作者： ZHANG Qing-zhu WANG Ming-gang WANG Shao-kun ZHANG Miao liu chuan-pu GU Yue-shu Department of Chemistry Shandong UniversityJinan 250100P.R.China

The abstraction reaction of H with (CH_3)_3SiH was investigated at the high levels of ab initio molecule orbital theory. The geometries were optimized at the MP2 level with 6-31G( d ) basis set, and G2MP2 level was used for the final energy calculations. The theoretical analysis provides the conclusive evidence that the main process is the hydrogen abstraction from the Si-H bond, leading to the formation of H_2 and silyl radicals; the hydrogen abstraction from the C-H bond has a higher barrier and is difficult to react. The kinetics was calculated with canonical variational transition-state theory (CVT) over the temperature range 200-1 000 K, and the theoretical rate constants match well with the later experimental values.

关键词： Reaction mechanism Variational transition state Tunneling effect Rate constant

A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 21-31页

作者： Lu liu Xingyu Wu Lufan Zhang chuan Wang School of Artificial Intelligence Beijing Normal University Applied Optics Beijing Area Major Laboratory Beijing Normal University

The multi-class classification of images is a pivotal challenge within the realm of image processing. As the volume of visual data continues to expand, there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification tasks. However, many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques, where the requisite circuit measurements increase linearly with the volume of training data. This work introduces a novel approach for training a quantum image multi-classifier based on the quantum search algorithm. We have meticulously conducted rigorous experiments on a handwritten digit dataset, a classic benchmark in the field. The results have been meticulously compared with previous works, and the comparative analysis not only validates the efficiency of our proposed approach, requiring only O(N/b) measurements during training, but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

Fe含量对钛铁矿原位反应合成Al_2O_3-Ti(C,N)-Fe复合材料的影响

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功能材料 2011年第4期42卷 722-725页

作者：刘胜明汤爱涛陈敏王健刘传璞重庆大学材料科学与工程学院重庆400044

利用钛铁矿通过碳热铝热原位还原反应、采用热压工艺制备了致密的Al2O3-Ti(C,N)-Fe复合材料,使钛铁矿两种主体成分Ti和Fe得到充分有效的利用。研究了Fe含量对制备过程、合成产物组织和性能的影响。结果表明,Fe含量的增加降低了碳热反应... 详细信息

利用钛铁矿通过碳热铝热原位还原反应、采用热压工艺制备了致密的Al2O3-Ti(C,N)-Fe复合材料,使钛铁矿两种主体成分Ti和Fe得到充分有效的利用。研究了Fe含量对制备过程、合成产物组织和性能的影响。结果表明,Fe含量的增加降低了碳热反应的温度;随Fe含量的增加,Fe相开始团聚,材料的组织都变得粗大;同时,随Fe含量的增加,Al2O3-Ti(C,N)-Fe复合材料的硬度稍有下降,抗弯强度明显降低。

关键词：热压烧结钛铁矿 Al2O3-Ti(C,N)-Fe 组织性能

A study of the quenching of PCl(b1∑+) by the E-V model

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Chinese Journal of Chemistry 1997年第3期15卷 211-217页

作者： liu, chuan-pu ZOU, Sheng-Li GUO, Jing-Zhong GU, Yue-ShuDepartment of Chemistry, Shandong University, Jinan, Shandong 250100, ChinaCHU, Yan-Nan CAO, De-ZhaoLaser Spectroscopy Laboratory, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China Department of Chemistry Shandong University Jinan Shandong 250 100 China Loser Spectroscopy Laboratory Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei Anhui 230031 China

Using the reaction of Ar(3Po,2) + PCl3 as a source of PCl(b1 +), we have measured the quenching rate constants of PCl(b,v'=0) for more than 20 quenchers. The E-V model is used to calculate the rate constants. The comparison of the calculated values with the experimental ones shows that the quenching of PCl(b) by the reagent molecules results from the electronic to vi-brational energy near resonance transfer and has been related to the Franck-Condon factors for the PCl(b,v'=0-a,v'=m) transition and to the anharmonicities of the terminal bonds of the quenchers. In addition, the influence of the polarizability of the reagent molecule on the quenching rate constant is discussed.

关键词： Metastable molecule PCl(b,1∑+) E-V energy transfer quenching rate constant

TiCN复合粉及Mo添加剂对铁基复合材料组织和性能的影响

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功能材料 2013年第23期44卷 3378-3382,3387页

作者：陈敏汤爱涛刘胜明赵子鹏王健刘传璞重庆大学材料科学与工程学院重庆400044

以成本低廉的钛铁矿经还原后得到的含Fe的碳氮化钛(TiCN)复合粉为增强相原料制备了铁基复合材料。结合金相组织观察、SEM和EDS分析以及力学性能测试研究了复合粉添加量对铁基复合材料组织和性能的影响,进一步研究了Mo的添加对铁基复合... 详细信息

以成本低廉的钛铁矿经还原后得到的含Fe的碳氮化钛(TiCN)复合粉为增强相原料制备了铁基复合材料。结合金相组织观察、SEM和EDS分析以及力学性能测试研究了复合粉添加量对铁基复合材料组织和性能的影响,进一步研究了Mo的添加对铁基复合材料组织与性能的影响。结果表明,复合粉的添加量为40%(质量分数)时制备的复合材料综合性能较好。复合材料中添加少量的Mo后增强相颗粒的平均尺寸减小,综合性能得到了提高。

关键词：复合粉铁基复合材料 Mo 组织硬度抗弯强度

钛铁矿制备Ti(C,N)粉C/N的控制研究

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功能材料 2013年第15期44卷 2271-2275页

作者：陈敏汤爱涛刘胜明赵子鹏王健刘传璞重庆大学材料科学与工程学院重庆400044

以钛铁矿和石墨为原料,在N2气氛下通过碳热还原法制备了粒度均匀的微米Ti(C,N)粉。结合X射线衍射分析,主要研究了Ti(C,N)粉制备过程中配碳量、反应温度、保温时间、N2分压对C/N的影响规律,获得了C/N控制关键因素及量化控制参数。

关键词：钛铁矿碳氮化钛碳热还原晶格常数

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钢管短芯棒拉拔过程应力场的数值模拟

钢铁 2005年第4期40卷 53-56页

作者：刘锦云刘传璞陶小贤查五生西华大学材料科学与工程学院四川成都610039

通过对一个典型的带芯棒拉拔过程的模拟,分析了在拉拔过程中芯模应力和钢管应力的分布特点。芯模的最大应力出现在芯模的浅表层,在周向表面上呈点状分布,而芯模其他部位承受的应力并不是很大。在拉拔过程中,芯模最大应力从芯模的定径带... 详细信息

通过对一个典型的带芯棒拉拔过程的模拟,分析了在拉拔过程中芯模应力和钢管应力的分布特点。芯模的最大应力出现在芯模的浅表层,在周向表面上呈点状分布,而芯模其他部位承受的应力并不是很大。在拉拔过程中,芯模最大应力从芯模的定径带和前倒角交界处附近转移到芯模定径带靠近芯模锥面附近。芯模的这种应力分布状况和芯模的失效形式密切相关,芯模应力在周向呈点状分布使得芯模局部容易产生粘着磨损,芯模的定径带附近承受交变的最大应力使得芯模容易产生微裂纹,微裂纹的扩展使得芯模开裂。钢管周向和径向的应力值不大,而轴向应力值较大,最大轴向应力出现在钢管与芯模的接触部位。

关键词：钢管短芯棒拉拔数值模拟

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou Ying Xiaoli Si Naijia Xue Yi liu Ran Zheng Ying Chen Jiali pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En Xu Ming-Lei Wu Ji-chuan liu Zi-Ling Shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response