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Precision Calculations of Atomic Polarizabilities： A Relevant Physical Quantity in Modern Atomic Frequency Standard

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Chinese Physics Letters 2010年第6期27卷 78-81页

作者： GAO Xiang LI jia-ming Department of Physics Shanghai Jiao Tong University Shanghai 200240 Department of Physics and Key Laboratory of Atomic and Molecular Nanosciences of Ministry of Education Tsinghua University Beijing 100084

Electric dipole polarizabilities of atoms are very important in many different physical applications, such as the precision atomic frequency standard. Calculations of these properties are very important and challenging. We propose a calculation strategy to calculate the frequency dependent dipole polarizabilities with high precision variationally by using a set of high quality orbital bases where the electron correlations can be taken into account adequately. The static polarizabilitiez of the ground state of Na are calculated accurately by such a method and can be compared with precision experiment measurement directly. The calculation result is in excellent agreement with the available experimental measurements within about 0.1~, which demonstrates the validity of our strategy. Our calculation strategy has a wide usage, not only in polarizibilies, but also in other fields such as theoretical treatment of electron-atom scattering processes. Using the same orbital bases, we carry out precision calculation of Na- affinities. Our calculated affinity is in excellent agreement with precision laser spectroscopy measurements within 0. 1%.

关键词： Computers Imports Sodium Accounting Experimentation Electronics Uses Measurement

Crevice Corrosion Behaviors Between CFRP and Stainless Steel 316L for Automotive Applications

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Acta Metallurgica Sinica(English Letters) 2019年第10期32卷 1219-1226页

作者： Xia-Yu Wu jia-Kun Sun jia-ming Wang Yi-ming jiang Jin Li Department of Materials Science Fudan University

Carbon fiber reinforced plastics (CFRP) are promising lightweight materials for vehicle applications. 316L is one of the most widely used types of austenite stainless steels and applied in lots of automotive applications. The existence of crevices will result in galvanic corrosion and crevice corrosion when CFRPs and 316L are directly connected. A crevice former for the galvanic system was therefore designed and applied to evaluate the crevice corrosion behaviors and study the mechanism of galvanic crevice corrosion through several electrochemical techniques in this research. The results showed that the crevice corrosion of galvanic systems grew from crevice mouth to the inside crevice and could be divided into four steps, metastable pitting corrosion at the crevice mouth, initiating step of crevice corrosion, propagating step and ending step of crevice corrosion. Because of the influences of the galvanic system, electrode reaction rates were speeded up and the passivation region was shortened at the initiating stage of crevice corrosion. Corrosion rate was observed to be higher in the galvanic system than that in normal crevice systems.

关键词： Crevice corrosion Galvanic system Carbon fiber reinforced plastics 316L stainless steels

STUDY ON THE SURFACE MODIFICATION OF NANO-TiO_2 BY GRAFTING PMMA/PBMA AND ITS THERMAL STABILITY

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Chinese Journal of Polymer Science 2005年第3期23卷 243-247页

作者：宇海银 jia-shanGu JunDu ming-yunGuan CollegeofChemistryandMaterialsScience AnhuiNormalUniversityWuhu241000China

The surface of nano-TiO_2 was encapsulated with hydroxyl-propyl-methyl cellulose(HPMC),and then cograftedwith *** of absorbing and grafting have been *** nano-TiO_2 particles were characterized byFT-IR spectra,TEM and TG *** was convinced from FT-IR studies that both methyl methacrylate(MMA)and butyl-methacrylate(BMA)were co-grafted onto the surface of nano-TiO_2 *** images show that the surface of nano-TiO_2 particles was successfully modified by a thick layer of film-like *** results demonstrate that the decompositiontemperature of HPMC-g-PMMA/PBMA,which has been grafted onto the surface of nano-TiO_2,is 56.9 K higher than that ofHPMC-g-PMMA/PBMA.

关键词： Hydroxyl-propyl-methyl cellulose Nano-TiO_2 particles Surface modification Cograft polymerization Thermal stability.

Interactions Between Surface Reactions and Gas-phase Reactions in Catalytic Combustion and Their Influence on Ignition of HCCI Engine

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Chemical Research in Chinese Universities 2006年第6期22卷 776-782页

作者： ZENG Wen XIE Mao-zhao jia ming Department of Power Engineering Dalian University of Technology Dalian 116024 P. R. China

The catalytic combustion of methane in a mierochannel whose surface was coated with platinum（Pt） catalyst was studied by numerical-simulation. The effects of gas-phase reactions on the whole catalytic combustion process were analyzed at a high inlet pressure. A sensitivity analysis of the detailed mechanisms of the surface reaction of methane on Pt revealed that the most sensitive reactions affecting the heterogeneous ignition are oxygen adsorption/desorption and methane adsorption, and the most sensitive reactions affecting the homogeneous ignition are OH and H2O adsorption/desorption. The combustion process of the homogeneous charge compression ignition（HCCI） engine whose piston face was coated with Pt catalyst was simulated. The effects of catalysis and the most sensitive reactions on the ignition timing and the concentration of the main intermediate species during the HCCI engine combustion are discussed. The results show that the ignition timing of the HCCI engine can be increased by catalysis, and the most sensitive reactions affecting the ignition timing of the HCCI engine are OH and H2O adsorption/desorption.

关键词： Heterogeneous ignition Homogeneous ignition Methane Homogeneous charge compression ignition (HCCI) Numerical simulation

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BIOCELL 2023年第1期47卷 109-123页

作者： LIPING GONG ming jia Department of Academic Research The Secondary HospitalCheeloo College of MedicineShandong UniversityJinan250033China Department of Cancer Center The Secondary HospitalCheeloo College of MedicineShandong UniversityJinan250033China

ATP binding cassette subfamily C member 8(ABCC8)encodes a protein regulating the ATP-sensitive potassium *** the level of ABCC8 mRNA in lower grade glioma(LGG)correlates with immune cell infiltration and patient outcomes has not been evaluated until *** of ABCC8 expression between different tumors and normal tissues were evaluated by exploring publicly available *** association between ABCC8 and tumor immune cell infiltration,diverse gene mutation characteristics,tumor mutation burden(TMB),and survival in LGG was also investigated in several independent *** enrichment analysis was conducted to search for ABCC8-associated signaling *** an online database,we found that ABCC8 expression in LGG was lower than in normal ***,the association of ABCC8 expression and immune cell infiltration in LGG was *** we expected,the ABCC8 mRNA levels were negatively associated with non-T immune cell infiltration levels in all ***,TCGA_LGG RNA-seq data revealed that ABCC8 downregulated several non-T immune cell-associated signaling pathways in gene set enrichment *** ABCC8 expression groups showed diverse gene mutation characteristics and *** high expression of ABCC8 was linked to improved survival of LGG patients.A pathway enrichment analysis of ABCC8-associated genes indicated that the GABAergic synapse signaling pathway might be involved in regulating immunity in *** findings show that ABCC8 reflects LGG tumor immunity and is an ideal prognostic biomarker for LGG.

关键词： ABCC8 Lower grade glioma Tumor immunity Tumor mutation burden Prognostic biomarker

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苦马豆素对家兔脾脏免疫功能及代谢的影响

动物医学进展 2025年第1期46卷 74-80页

作者：赵金香陶大勇杜国丰张家鸣沈佳宜矫继峰营口理工学院辽宁营口115014 塔里木大学动物科学学院新疆阿拉尔843300

为了探讨苦马豆素通过消化系统对家兔脾脏免疫功能和代谢的影响,将体重为(1.9±0.12)kg的24只家兔随机分成对照组与试验组,每组雌、雄各半。试验组家兔饲喂含有小花棘豆的自制颗粒饲料,饲喂苦马豆素剂量为2 mg/(kg·d),对照组家兔饲喂... 详细信息

为了探讨苦马豆素通过消化系统对家兔脾脏免疫功能和代谢的影响,将体重为(1.9±0.12)kg的24只家兔随机分成对照组与试验组,每组雌、雄各半。试验组家兔饲喂含有小花棘豆的自制颗粒饲料,饲喂苦马豆素剂量为2 mg/(kg·d),对照组家兔饲喂自制颗粒饲料中不含小花棘豆。所有家兔单笼饲养,自由饮水,每天观测并记录家兔的健康状态。在试验的第60天,采取所有家兔脾脏,对脾脏进行基于iTRAQ的定量蛋白质组学分析、生物信息学分析及关键蛋白质的Western blot验证。结果显示,所有试验组家兔均呈现明显的中毒现象。与对照组相比,共鉴定出315个与新陈代谢(81%)及免疫相关(15%)的差异表达蛋白质(>1.5倍或<1/1.5倍)。而且,苦马豆素中毒家兔脾脏细胞分解代谢处于激活状态,但其免疫反应处于抑制状态。说明苦马豆素抑制了家兔脾脏的免疫功能,激活了脾脏组织的分解代谢。

关键词：苦马豆素小花棘豆脾脏同位素标记的相对和绝对定量技术蛋白质组免疫家兔

How does conserved dopamine neurotrophic factor protect against and rescue neurodegeneration of PC12 cells？

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Neural Regeneration Research 2017年第7期12卷 1145-1151页

作者： jia-ming Mei Chao-shi Niu Shandong University Jinan Shandong Province China Department of Neurosurgery Anhui Provincial Hospital Hefei Anhui Province China

Conserved dopamine neurotrophic factor protects and rescues dopaminergic neurodegeneration induced by 6-hydroxydopamine in vivo,but its potential value in treating Parkinson＇s disease remains ***,we used the proteasome inhibitors lactacystin and MG132 to induce neurodegeneration of PC12 ***,conserved dopamine neurotrophic factor was administrated as a therapeutic factor,both pretreatment and *** results showed that（1）conserved dopamine neurotrophic factor enhanced lactacystin/MG132-induced cell viability and morphology,and attenuated alpha-synuclein accumulation in differentiated PC12 cells.（2）Enzyme linked immunosorbent assay showed up-regulated 26S proteasomal activity in MG132-induced PC12 cells after pre-and posttreatment with conserved dopamine neurotrophic ***,26S proteasome activity was upregulated in lactacystin-induced PC12 cells pretreated with conserved dopamine neurotrophic factor.（3）With regard proteolytic enzymes（specifically,glutamyl peptide hydrolase,chymotrypsin,and trypsin）,glutamyl peptide hydrolase activity was up-regulated in lactacystin/MG132-administered PC12 cells after pre-and posttreatment with conserved dopamine neurotrophic ***,upregulation of chymotrypsin activity was only observed in MG132-administered PC12 cells pretreated with conserved dopamine neurotrophic *** was no change in trypsin *** conclude that conserved dopamine neurotrophic factor develops its neurotrophic effects by modulating proteasomal activities,and thereby protects and rescues PC12 cells against neurodegeneration.

关键词： nerve regeneration conserved dopamine neurotrophic factor Parkinson's disease proteasomal inhibitor 26S proteasome alphasynuclein lactacystin MG-132 glutamyl peptide hydrolase chymotrypsin trypsin neural regeneration

An Effective Eigenchannel R-Matrix Method for Calculating Electron-Ion Scattering Processes with Spectroscopic Precision

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Chinese Physics Letters 2012年第3期29卷 71-74页

作者： GAO Xiang LI jia-ming Beijing Computational Science Research Center Beijing 100084 Key Laboratory for Laser Plasmas(Ministry of Education)and Department of Physics Shanghai Jiao Tong UniversityShanghai 200240 Department of Physics and Center for Atomic and Molecular Nanosciences Tsinghua UniversityBeijing 100084

The electron-ion scattering processes are very important in various scientific research fields such as astrophysical studies and inertial confinement fusion *** report our recent development of an efficient method for providing such atomic data with spectroscopic *** on the Breit-Pauli and the Dirac R-matrix theory,we develop two eigenchannel R-matrix codes,referred to as R-eigen(non-relelativistic eigenchannel R-matrix)and R-R-eigen(relativistic eigenchannel R-matrix),to directly calculate the physical quantities in multichannel quantum defect theory in the whole energy *** such physical quantities,we can obtain all energy levels and the related scattering cross sections with accuracies comparable with spectroscopic *** e+Kr+system is used as an illustration example,the degrees of accuracies of scattering matrices are calculated within about 2%,which should be much more accurate than state-of-the-art scattering experiments.

关键词： quantities spectroscopic illustration

Theoretical Simulation of the Transmission Spectra of Fe and Ge Plasmas

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Chinese Physics Letters 2000年第3期17卷 194-196页

作者： YAN Jun LI jia-ming Center of Atomic and Molecular Sciences Department of PhysicsTsinghua UniversityBeijing 100084 Institute of Physics Chinese Academy of SciencesBeijing 100080

Using the detailed conGguration accounting with the term structures treated by the unresolved transition array model,we present a method to calculate the transmission spectra of hot dense *** to the fully relativistic treatment,incorporated with the quantum defect theory to calculate the atomic parameters of the huge number of conGgurations with high principal quantum number,we can study the opacities for any middle-and high-Z plasmas with much less computational *** can also conveniently identify the dominant configurations and the detailed features of transition arrays,which are very helpful for the diagnostic of the plasma *** accuracy of our theoretical model is tested by comparing the calculated transmission spectra of Fe and Ge plasmas with the bench mark experimental data.

关键词： conditions. quantum transition