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In-situ TEM Observation of Dislocation Emission, Multiplication and Motion Induced by Anodic Dissolution in Type 310 Stainless Steel

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Journal of Materials Science & Technology 1996年第3期12卷 215-218页

作者： huang, YZ chen, qz Chu, WY Dept. of Materials Physics University of Science and Technology Beijing Beijing 100083 China

A special constant deflection device for TEM has been designed and then the dislocation configuration change ahead of a loaded crack tip after corrosion or anodic dissolution for some time but before the initiation of SCC can be observed in TEM. The results showed that anodic dissolution during SCC of a type 310 stainless steel in deionized water could promote dislocation emission, multiplication and motion before the initiation of SCC.

关键词： TEM In-situ TEM Observation of Dislocation Emission Multiplication and Motion Induced by Anodic Dissolution in Type 310 Stainless Steel

Effect of Austenite Ageing on Martensitic Transformation

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Journal of Materials Science & Technology 1997年第6期13卷 508-514页

作者： chen, qz Wu, XF Wei, LY Ke, J Univ Sci & Technol Beijing Dept Mat Phys Beijing 100083 Peoples R China

The effect of austenite ageing on martensite transformation in an iron and nickel alloy was studied. Attention was paid to the variation of dislocation configurations in austenite before martensite transformation, The clusters or precipitates produced during austenite ageing and the alteration of dislocation configurations affect together the consequent martensite transformation. Dispersed fine clusters and precipitates cripple nucleus role of special dislocation configurations and drop M-s. Coarse precipitates make M-g rise again. Densely piled up dislocations in nuclei lead to rise of M-s. All the changes in austenite are of benefit to small martensite plates.

关键词： Iron alloys

Chemisorbed　dimethylammonium　chlorochromate　as　selective　oxidants　for　primary　and　second　aryAlcohols

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Chinese Chemical Letters 1996年第11期7卷 973-974页

作者： Zhang, GS Shi, qz chen, MF Cai, K HENAN NORMAL UNIV DEPT CHEMXINXIANG 453002PEOPLES R CHINA

Two new reagents. dimethylammonium chlorochromale adsrbed on alumina and silicagel are describe as convenient reagents for efficient oxidation of a variety of primary and secondaryalcohols. These two reagents are very... 详细信息

关键词： selective and aryAlcohols chlorochromate dimethylammonium oxidants primary Chemisorbed

The initial elevation of palaeokarst and planation surfaces on Tibet Plateau

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Chinese Science Bulletin 1997年第11期42卷 934-939页

作者： Cui, ZJ Gao, qz Liu, GN Pan, BT chen, HL Department of Geography Peking University Beijing China Department of Geography Lanzhou University Lanzhou China

THE formation periods,properties and initial elevations of Tibetan planation surfaces are keysto the issues ot the plateau *** et *** that the study on planation surfaces hasfar-reaching *** et *** that the summit lev... 详细信息

关键词： Tibet Plateau planation surface period elevation.

Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 182-190页

作者： Shaorou Ke Yajing Zhao Xin Min Yanghong Li Ruiyu Mi Yangai Liu Xiaowen Wu Minghao Fang Zhaohui huang Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastersNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China

Pt-based nanocatalysts offer excellent prospects for various ***,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable *** this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ ***~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt *** unique structure is beneficial for the hydrogen evolution *** catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C *** activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.

关键词： hydrogen evolution reaction ultralow platinum in-situ synthesis ultrasound

Neuronal growth inhibitory factor inhibits pheochromo-cytoma PC12 in vitro

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Chinese Science Bulletin 2002年第2期47卷 132-135页

作者： Ji, qz Ru, BG Peking Univ Natl Lab Prot Engn Coll Life Sci Beijing 100871 Peoples R China

Neuronal growth inhibitory factor (GIF), named Metallothioneins-III (MT-III), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochro-mocytoma PC12 by the MTT (Thiazolyl blue) reduction as-say. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for de-tecting neuronal growth inhibitory activity of GIF. Recom-binant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhib-iting PC12 may be that PC12 have some properties of cho-linergic neuron. It must play an important role in discover-ing the mechanism of GIF’s neuronal growth inhibitory ac-tivity.

关键词： neuronal growth inhibitory factor pheochromocytoma PC12 neuroblastoma SY5Y MTT reduction assay.

OPTIMAL CONTROL OF STRETCHING PROCESS OF SOLAR ARRAYS ON SPACECRAFT USING WAVELET EXPANSION METHOD

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Acta Mechanica Solida Sinica 1998年第4期11卷 351-358页

作者： Ge, XS Zhang, qz Liu, YZ Beijing Inst Machinery Ind Beijing 100085 Peoples R China Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200030 Peoples R China

The optimal attitude control problem of spacecraft during its solar arrays stretching process is discussed in the present paper. By using the theory of wavelet analysis in control algorithm, the discrete orthonormal wavelet function is introduced into: the optimal control problem, the method of wavelet expansion is substituted for the classical Fourier basic function. An optimal control algorithm based on wavelet analysis is proposed. The effectiveness of the wavelet expansion approach is shown by numerical simulation.

关键词： spacecraft optimal control solar arrays stretching wavelet expansion

SELECTIVE　OXYGENATION　OF　CYCLOHEXENE　WITH　DIOXYGEN　USING　POLYOXOMETALATE　INTERCALATED　LAYERED　DOUBLE　HYDROXIDES

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Chinese Chemical Letters 1996年第6期7卷 531-534页

作者： Guo, J Jiao, qz Xiong, G Lu, HJ Jiang, DZ Min, EZ JILIN UNIV DEPT CHEM CHANGCHUN 130023 PEOPLES R CHINA RES INST PETR PROC BEIJING 100083 PEOPLES R CHINA

Cyclobexene was seleetively oxidized with dioxygeh by polyoxometalateintercalated layered double hydroxides to Produce 2-eyelobexene-one and2-ctclobexene-0 1undet mi id reaction *** talate p i I fared I ale red doub ie hydrox ideB (POa-LDHB) ate a newc lass of catalyt ic mater ial s deve loged in fecent yearB 11- 3]. *** it UBe as catalyBts bas not been we I I developed. Recent ly, M. A. Drezdzon teFor ted that the V,.0.:- and Mo.0::- an ions F if fared *** arefound to be effect ive catalyBts for convers ion of 2-Propanol and delydtogenat ion of butylethylbenzene [4]. Pinnavaia has noted that the BVW,,0.;SiV.W.0.;--, and 11.W,.0.g- an ionB intetcalated *** are b igh ly act ivecatalyBts for pbotocatal yi ic oxidat ion of isopropanol to acetone 15]. *** and co-workers have demonstrated that some POa intercalated bydroxi6es slow good catalyt ic act ivi t ies for the sbage Be feet ive eFoxidation of alienes with H:0. aB oxidant [6]. Recently, Xu laB found that someLDHs and tleit POa intercalates are highly active catalysts fot tie alkylation of butene with isobutane 171. The studieB of these mater ials ihcatalyt ic oxidat ion, however, have rece tved I lit ie attent *** oxi6at ion of organic substrates wi th molecu far oxygen is very attract ive from the v iewgoint of induBtr ial technology and synthet ic organ icchemistry & nice molecular oxygen is cheap, env ironmental ly c lean and eaBy to handle IS]. I t bas been known that many trans it ion me tal compounds,l the metal loporpbyr ins 191, organome ta I I ic compounds 110] 1 and po lyoxome talates 111] t etc. j have been use6 fot sc feet ive oxidat ion of alkenes andalkanes with moleculat oxygen. However, tlete is no regott on the': TIts lroject,.s sugported by the *** ion of lydrocarbons kith diolygen us lug LDHS and tie it POa intercalateB. In our pie, ionB,otk,,e la,e demonBttated tlat some LDH exb fo itgood catalyt ic act l, it tea for oxldat ion of eye lolexene wi t

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Role of the globus pallidus in motor and non-motor symptoms of Parkinson's disease

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Neural Regeneration Research 2025年第6期20卷 1628-1643页

作者： Yimiao Jiang Zengxin Qi Huixian Zhu Kangli Shen Ruiqi Liu chenxin Fang Weiwei Lou Yifan Jiang Wangrui Yuan Xin Cao Liang chen Qianxing Zhuang Department of Physiology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Neurosurgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghaiChina National Center for Neurological Disorders ShanghaiChina Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration ShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institute of Brain ScienceFudan UniversityShanghaiChina

The globus pallidus plays a pivotal role in the basal ganglia circuit. Parkinson's disease is characterized by degeneration of dopamine-producing cells in the substantia nigra, which leads to dopamine deficiency in the brain that subsequently manifests as various motor and non-motor symptoms. This review aims to summarize the involvement of the globus pallidus in both motor and non-motor manifestations of Parkinson's disease. The firing activities of parvalbumin neurons in the medial globus pallidus, including both the firing rate and pattern, exhibit strong correlations with the bradykinesia and rigidity associated with Parkinson's disease. Increased beta oscillations, which are highly correlated with bradykinesia and rigidity, are regulated by the lateral globus pallidus. Furthermore,bradykinesia and rigidity are strongly linked to the loss of dopaminergic projections within the cortical-basal ganglia-thalamocortical loop. Resting tremors are attributed to the transmission of pathological signals from the basal ganglia through the motor cortex to the cerebellum-ventral intermediate nucleus circuit. The cortico–striato–pallidal loop is responsible for mediating pallidi-associated sleep disorders. Medication and deep brain stimulation are the primary therapeutic strategies addressing the globus pallidus in Parkinson's disease. Medication is the primary treatment for motor symptoms in the early stages of Parkinson's disease, while deep brain stimulation has been clinically proven to be effective in alleviating symptoms in patients with advanced Parkinson's disease,particularly for the movement disorders caused by levodopa. Deep brain stimulation targeting the globus pallidus internus can improve motor function in patients with tremordominant and non-tremor-dominant Parkinson's disease, while deep brain stimulation targeting the globus pallidus externus can alter the temporal pattern of neural activity throughout the basal ganglia–thalamus network. Therefore, the comp

关键词： anxiety basal ganglia bradykinesia deep brain stimulation depression globus pallidus externus globus pallidus internus lateral globus pallidus medial globus pallidus neural circuit Parkinson's disease