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单轴应变对本征和N掺杂4H-SiC电子结构的影响

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原子与分子物理学报 2025年第3期42卷 173-179页

作者：秦彦军张建强杨慧雅方峥范晓珍邝富丽叶慧群方允樟浙江师范大学物理与电子信息工程学院金华321004 新疆理工学院理学院阿克苏843100 浙江旅游职业学院杭州311231

采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙... 详细信息

采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙达到最大值.对态密度的分析可知本征和N掺杂4H-SiC的价带顶主要来自Si 3p和C 2p态电子,导带底主要来自Si 3p态电子,C 2p态和Si 3p态通过影响价带顶和导带底从而导致应变结构中带隙发生变化.通过Mulliken布局和差分电荷密度分析可知,随着晶格常数的增加Si原子向C原子和N原子转移的电荷减少,同时Si-C原子和Si-N原子之间的共价性减弱.

关键词： 4H-SiC 单轴应变电子结构第一性原理

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肝门部胆管癌手术治疗:附64例报告

中国普通外科杂志 2007年第2期16卷 158-160页

作者：王海东郑进方邢贻雷吴奕强龙籍典海南省人民医院肝胆外科海南海口570311

目的探讨肝门部胆管癌手术方式。方法回顾性分析15年间我院收治的64例肝门部胆管癌的临床资料,包括临床表现、临床分型、手术方式及治疗效果。其中35例行手术切除,包括根治性切除16例,姑息性切除19例;29例行胆管引流术,包括胆肠内引流... 详细信息

目的探讨肝门部胆管癌手术方式。方法回顾性分析15年间我院收治的64例肝门部胆管癌的临床资料,包括临床表现、临床分型、手术方式及治疗效果。其中35例行手术切除,包括根治性切除16例,姑息性切除19例;29例行胆管引流术,包括胆肠内引流术16例,胆管外引流术13例。结果根治性切除组1,2,3年生存率分别是80.0%,53.3%及26.7%;姑息切除组1,2,3年生存率分别为50.0%,16.7%,0%;胆肠内引流组1,2年生存率分别是45.5%和18.2%;外引流组则为25.0%和0。结论手术切除特别是根治性切除治疗是提高肝门部胆管癌疗效和提高远期生存率可选择的方法。

关键词：胆管肿瘤/外科学胆管肝内/外科学

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分布式球形容器CAPP系统

四川轻化工学院学报 2004年第1期17卷 25-27页

作者：贺元成郑国君兰芳四川轻化工学院机电工程系四川自贡643033

文章在讨论现代CAPP系统特点的基础上,分析组件技术、分布式数据库技术对CAPP系统的作用,结合某企业的CAPP系统实施情况,介绍了面向产品的分布式球形容器CAPP系统。

关键词：组件分布式面向产品 CAPP

Effect of metallurgical dust on NO emissions during coal combustion process

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Journal of Iron and Steel Research International 2018年第1期25卷 19-27页

作者： Zhi-fang Gao Hong-ming Long Tie-jun Chun Zhao-jin Wu zheng-wei Yu School of Metallurgy Engineering Anhui Universityof Technology Ma'anshan 243002 Anhui China Key Laboratory of Metallurgical Emission Reductionand Resources Recycling Ministry of Education AnhuiUniversity of Technology Ma'anshan 243002 Anhui China

NO emissions from coal combustion are receiving significant attention in recent years. As a solid waste generated from metallurgical industry, metallurgical dust （MD） contains a large amount of metal oxides, such as Fe2O3, CaO, SiO2 and Al2O3, as well as other rare metal oxides. The influence of MD on the NO emissions and the mechanism of the coal com- bustion systems were analyzed. The results show that the peak values of NO emission decrease with the increase in MD mass percent, and the curve of NO emission can be divided into two stages including rapid generation （400-600 ℃） and slow release （800-900 ℃）. The reduction of NO is significantly affected by temperature, volatile components, 02 and CO. CO has a significant catalytic action which can deoxidize NO to N2. The results obtained by X-ray diffraction and scanning electron microscopy indicate that multiple components in MD, such as FegTiO15, Fe2O3 and TiO2, can react with NO to produce TiN. Besides, the alkali metals in MD, such as Na, K and Ca, may catalyze NO precursor to inhibit NO emission. These results indicate that MD is cheap and highly efficient in controlling NO emissions during coal combustion processes.

关键词： Metallurgical dust NO emission Reaction mechanism Coal combustion

Conformational changes and surface binding property of rat liver Cd_(5)Zn_(2)-metallothionein

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Chinese Journal of Chemistry 1997年第5期15卷 385-394页

作者： HUANG Zhong-Xian GU Wei-Qiang zheng Qi LIU fang SUN Yao-jun Department of Chemistry Fudan UniversityShanghai 200433China

A series of conformational changes of native rat liver metallothionein were observedunder different ionic strength by 1H NMR. Furthermore, binding of magnetic probes to MT gives us an implication that positively charged groups of lysine are not completely folded back towards the inner core of metallothionein, the negatively charged metal-sulfur core is slightly exposed to the solvent.

关键词： Rat liver metallothionein NMR studies of protein magnetic relaxation probe

Gastric neuroendocrine tumors in a BRCA2 germline mutation carrier:A case report

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World Journal of Gastrointestinal Oncology 2023年第8期15卷 1497-1504页

作者： Hui-fang Zhang Yi zheng Xue Wen Jing Zhao jun Li Department of Pathology The First Affiliated HospitalMedical CollegeZhejiang UniversityHangzhou 310000Zhejiang ProvinceChina

BACKGROUND The molecular changes present in gastric neuroendocrine tumors(NETs)include a loss of heterozygosity or mutation of MEN1,CDKN1B gene mutation,P27 heterozygous mutation,and ATP4A gene missense *** identified and are the first to report a case of type 1 histamine-producing enterochromaffin-like cell NETs(ECL-cell NETs)with a BRCA2 gene germline *** SUMMARY The patient had a history of iron-deficient anemia for 5 years,and gastroscopic examination indicated multiple gastric ***,the patient underwent distal ***,multifocal tumor cells were found in the mucosa and submucosa;tumor cells were organoid and arranged in nests and cords,and the stroma was rich in *** surrounding gastric mucosa showed atrophy with mild intestinal metaplasia or pseudopyloric gland *** cells could be seen with diffuse linear,nodular,and adenomatous ***,the tumor cells diffusely expressed cytokeratin,chromogranin,synaptophysin,and ***-genome highthroughput molecular sequencing revealed a pathogenic germline mutation in the BRCA2 gene,a heterozygous germline frameshift mutation in exon 11,c.6443_6444del(p.S2148Yfs*2).The final diagnosis was gastric type 1 ECL-cell NETs with a BRCA2 gene germline mutation,accompanied by autoimmune *** This is the first report of a case of type 1 gastric ECL-cell NETs with a pathogenic germline mutation of the BRCA2 *** findings of this report will expand the germline mutation spectrum of gastric NETs and increase the understanding of the molecular changes present in these tumors for their improved diagnosis in the future.

关键词： Gastric Neuroendocrine tumor Enterochromaffin-like cell neuroendocrine tumors Type 1 enterochromaffin-like cell neuroendocrine tumors BRCA2 Germline mutation Case report

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui zheng Chao fang Fukun Hong Min Zhang Fulong Gao Yusheng Zhang jun Bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： Qing-jun Du Hao-Yu zheng Jian Hou Yong-Ge Liu Jian-fang Sun Dong Zhao State Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao266237ShandongPR China Petroleum Exploration and Production Research Institute SINOPECBeijing10083PR China

Hot water flooding is an effective way to develop heavy oil ***,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the *** pore structure heterogeneity is an important factor in forming these *** study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments,computer tomography(CT)scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling *** oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure *** zone where oil saturation reduction exceeds 20%is defined as a channeling *** scanning area is divided into 180 equally sized zones based on the CT scanning images,and threedimensional(3D)distributions of the channeling channels are *** micro remaining oil distribution patterns are proposed,and the morphology characteristics of micro remaining oil inside and outside the channeling channels are *** results show that hot water flooding is more balanced in the weakly heterogeneous model,and the oil saturation decreases by more than 20%in most zones without narrow channeling channels *** the strongly heterogeneous model,hot water flooding is unbalanced,and three narrow channeling channels of different lengths *** the weakly heterogeneous model,the oil saturation reduction is greater in zones with larger *** distribution range of the average pore size is larger in the strongly heterogeneous *** network remaining oil inside the channeling channels is less than outside the channeling channels,and the hot water convert

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

Effects of refining process on Camellia vietnamensis oil: Phytochemical composition, antioxidant capacity, and anti-inflammatory activity in THP-1 macrophages

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Food Bioscience 2023年第2期52卷 980-989页

作者： Yuxin Guo zheng Jia Liting Wan jun Cao Yajing fang Weimin Zhang School of Food Science and Engineering Hainan UniversityKey Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market RegulationHainan Institute for Food ControlHaikou570228PR China

This study aimed to explore the changes in phytochemical composition and inflammatory response of Camellia vietnamensis oil(CO)during *** refined CO samples[degummed(DGO),deacidified(DAO),decolorized(DCO),and deodorized(DOO)]were prepared from crude CO(CCO).Five CO samples were measured for their composition of fatty acids,sterols,tocopherols,polyphenols,and oxidation products as well as anti-inflammatory activity in lipopolysaccharide(LPS)-induced THP-1 *** content of phytochemicals was significantly decreased with the deepening of the refining degree,especially after *** and DGO showed anti-inflammatory activity by inhibiting the production of pro-inflammatory cytokines and activation of NF-κB induced by *** and decolorization of CO decreased its anti-inflammatory *** accumulation of oxidation products after deodorization in CO aggravated the inflammatory ***-cinnamic,kaempferol,and protocatechuic acid in CO were crucial for their anti-inflammatory *** findings underlined that moderate refinement is suggested to retain its bioactive ingredients and anti-inflammatory ability.

关键词： Camellia vietnamensis Refining process Oxidation products Polyphenols Inflammatory response