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Reoxidation process and corrosion behavior of TA15 alloy by laser ablation

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Rare Metals 2021年第4期40卷 865-876页

作者： Bo-wen Liu Gao-yang Mi chun-Ming Wang School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

The thermal oxide layer formed of TA15 alloy has poor corrosion *** this paper,the changes of the elements and components on the surface after laser ablation with different energy densities(E) were *** formation process and corrosion behavior of laser-generated oxide layer were *** E increases,the oxygen content decreases from 8.52% to 5.43% and then increases to 11.89%.The surface oxide layer changes from TiO_(2)(R)(i.e.,rutile) to Ti_(2) O_(3)+TiO_(2)(R) and finally becomes TiO_(2)(R)+TiO_(2)(A)(i.e.,anatase).The TiO_(2)(R) gasification was confirmed by calculating the surface temperature *** surface reoxidation process was illustrated by a thermodynamically calculated ΔGT(i.e.,the Gibbs free energy changes with temperature).When E≥17.5 J·cm^(-2),the oxide layer exhibits an agitated morphology,and oxide falls off at the *** E increases,the corrosion rate decreases first and then *** energy density of 8.75 J·cm^(-2),the surface corrosion rate was 20.43 times slower than that of the untreated *** impedance spectrum and equivalent resistance results also prove the best corrosion resistance at 8.75 J·cm^(-2).The corrosion behavior of the oxide layer is analyzed from the properties of the oxide layer components and the reaction products with the electrolyte.

关键词： Laser ablation TA15 alloy Reoxidation process Corrosion behavior Elemental analysis

Measurement of k_(eff) by delayed neutron multiplication in subcritical systems

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Nuclear Science and Techniques 2018年第2期29卷 118-124页

作者： Bin Ye Chao-wen yang chun Zheng College of Physical Science and Technology Sichuan University Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics

In this paper, we build on the concept of equivalent fundamental-mode source to propose using delayed neutrons as a neutron source in multiplication experiments to acquire the effective multiplication factor keffof subcritical systems, which is difficult to acquire directly from conventional neutron source multiplication method. We analyzed the difference between a fundamental-mode fission source and delayed neutron source,then adopted a factor to convert delayed neutron distribution to an equivalent fundamental-mode source distribution, and employed Monte Carlo code to acquire this *** delayed neutron multiplication measurement method was established for the first time, and corresponding experiments were conducted in subcritical systems. The multiplication of delayed neutrons was measured based on Chinese Fast Burst Reactor-Ⅱ(CFBR-Ⅱ) at subcritical states, and keffwas acquired from delayed neutron multiplication successfully(0.9921 and 0.9969, respectively).The relative difference between k_(eff)obtained by the new method and previous values acquired by the positive period method is less than 1% for these two studied cases.

关键词： keff Delayed neutrons Neutron source multiplication Subcritical system

Pointwise Characterizations of Besov and Triebel–Lizorkin Spaces with Generalized Smoothness and Their Applications

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Acta Mathematica Sinica,English Series 2022年第4期38卷 623-661页

作者： Zi Wei LI Da chun yang wen YUAN Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this article,the authors first establish the point wise characterizations of Besov and Triebel-Lizorkin spaces with generalized smoothness on R;via the Hajlasz gradient sequences,which serve as a way to extend these spaces to more general metric measure ***,on metric spaces with doubling measures,the authors further prove that the Besov and the Triebel-Lizorkin spaces with generalized smoothness defined via Hajlasz gradient sequences coincide with those defined via hyperbolic *** an application,some trace theorems of these spaces on Ahlfors regular spaces are established.

关键词： Besov space Triebel-Lizorkin space generalized smoothness Hajlasz gradient hyperbolic filling trace

高校蔬菜供应点蔬菜中亚硝酸盐含量的测定和分析

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兰州文理学院学报（自然科学版） 2015年第4期29卷 50-53页

作者：李雪梅罗冬梅杨春文兰州文理学院化工学院甘肃兰州730000

为了解高校食堂中蔬菜食品安全的实际情况,研究选取了甘肃省5所高校食堂中最为常见的15种蔬菜,采用不同方式处理后,对其所含亚硝酸盐含量进行测定,以期为广大师生选择低含量蔬菜提供依据.结果表明:亚硝酸盐的含量室温>冷藏;采用不同处... 详细信息

为了解高校食堂中蔬菜食品安全的实际情况,研究选取了甘肃省5所高校食堂中最为常见的15种蔬菜,采用不同方式处理后,对其所含亚硝酸盐含量进行测定,以期为广大师生选择低含量蔬菜提供依据.结果表明:亚硝酸盐的含量室温>冷藏;采用不同处理方式的蔬菜,其亚硝酸盐的含量随着烹调时间的延长都有不同程度的增加,即生样>爆炒>焖煮;保存时间不同,放置条件不同,亚硝酸盐含量不同;摄食部位不同,亚硝酸盐含量不同,即叶菜类>果菜类>茎菜类>花菜类>根菜类.

关键词：高校食堂蔬菜亚硝酸盐分光光度法

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“共建共治共享”的乡村治理共同体何以建构

河北学刊 2025年第1期45卷 193-201页

作者：王春城郭一文燕山大学公共管理学院河北省高校人文社会科学重点研究基地燕山大学县域振兴发展政策研究中心

以“共建共治共享”为导向建构乡村治理共同体,是回应新时代中国乡村治理诉求的必然要求,而现实图景的生成,需要从学理上探究其系统建构逻辑,明确其价值意蕴、要素体系与行动框架。顺应乡村治理方向的时代变迁,建构乡村治理共同体,要响... 详细信息

以“共建共治共享”为导向建构乡村治理共同体,是回应新时代中国乡村治理诉求的必然要求,而现实图景的生成,需要从学理上探究其系统建构逻辑,明确其价值意蕴、要素体系与行动框架。顺应乡村治理方向的时代变迁,建构乡村治理共同体,要响应政治价值、社会价值和公共价值,这些价值意蕴促使乡村治理共同体成为提升乡村治理效能的重要途径。乡村治理共同体的核心内涵集中体现在组织、价值、行动、利益等要素的关联契合之中,组织架构、价值理念、行动指向、利益成果可作为乡村治理共同体的建构体系。以价值意蕴的指引和要素体系的支撑为基础,乡村治理共同体建构的具体行动可通过以主体互嵌优化乡村治理结构、以价值融通重塑乡村治理理念、以协同共治完善乡村治理方式、以利益聚合共享乡村治理成果四个方面入手,以乡村治理共同体推进乡村治理的网络化、共识化、协同化和共享化,从而以“共建共治共享”的共同体塑造乡村治理新格局。

关键词：乡村治理共同体共建共治共享

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猪苓多糖提取工艺的优化

北方园艺 2010年第20期 178-180页

作者：王晶晶杨春文张莹莹董英伟杜带弟牡丹江师范学院黑龙江牡丹江157012

对猪苓多糖的提取过程进行了研究。结果表明:猪苓多糖的最佳提取工艺为:用乙醇含量为70%,pH值为6.5的提取液提取;用Sevag法去除蛋白效果最好;用氧化脱色法除色素效果最好;分级沉淀时乙醇浓度为80%时效果最好。

关键词：猪苓多糖提取工艺优化乙醇

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镉胁迫对珍珠梅生理生态特征的影响

北方园艺 2010年第13期 72-74页

作者：王晶晶杨春文蔡赫李然红张莹莹马威牡丹江师范学院黑龙江牡丹江157012

研究了不同浓度镉(Cd)胁迫对珍珠梅生理生态特性的影响。结果表明:与对照相比,低浓度镉胁迫下,珍珠梅含水量、叶绿素含量、丙二醛含量和超氧化物歧化酶活性均有提高,说明珍珠梅对Cd具有较强的抗性;叶和根中的可溶性蛋白含量随着镉浓度... 详细信息

研究了不同浓度镉(Cd)胁迫对珍珠梅生理生态特性的影响。结果表明:与对照相比,低浓度镉胁迫下,珍珠梅含水量、叶绿素含量、丙二醛含量和超氧化物歧化酶活性均有提高,说明珍珠梅对Cd具有较强的抗性;叶和根中的可溶性蛋白含量随着镉浓度的增加而降低;高浓度镉胁迫下,珍珠梅各器官含水量、叶绿素含量、丙二醛含量和超氧化物歧化酶活性均有所降低。

关键词：珍珠梅镉叶绿素超氧化物歧化酶丙二醛

Synthesis of New Chiral C_2-Symmetrical Bis(oxazoline) Compounds

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Chinese Chemical Letters 2003年第2期14卷 125-126页

作者： chun Hua ZHANG Nian Fa yang Li wen yang Department of Chemistry Xiangtan UniversityXiangtan 411105

New chiral C_2-symmetrical bis(oxazoline) compounds bearing one isobutyl-, secbutyl-, benzyl- or isopropyl-substituent at the 4-position have been prepared and characterized.

关键词： Synthesis chiral C_2-symmetrical bis(oxazoline).

Genetic types and geochemicai characteristics of natural gases in the Jiyang Depression,China

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Petroleum Science 2015年第1期12卷 81-95页

作者： wen-Tao Li yang Gao chun-Yan Geng School of Energy Resources China University of Geosciences Geoscience Research Institute Shengli Oilfield Company SINOPEC

Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, light hydrocarbon properties, as well as geological analysis, natural gases in the Jiyang Depression are classified into two types, one is organic gas and the other is abiogenic gas. Abiogenic gas is mainly magmatogenic or mantlederived CO2. Organic gases are further divided into coaltype gas, oil-type gas, and biogas according to their kero- gen types and formation mechanisms. The oil-type gases are divided into mature oil-type gas （oil-associated gas） and highly mature oil-type gas. The highly mature oil-type gases can be subdivided into oil-cracking gas and kerogen thermal degradation gas. Identification factors for each kind of hydrocarbon gas were summarized. Based on genesis analysis results, the genetic types of gases buried in different depths were discussed. Results showed that shallow gases （〈1,500 m） are mainly mature oil-type gases, biogas, or secondary gases. Secondary gases are rich in methane because of chromatographic separation during migration and secondary biodegradation. Secondary biodegradation leads to richness of heavy carbon isotope ratios in methane and propane. Genesis of middle depth gases （1,500-3,500 m） is dominated by mature oil-type *** gases （3,500-5,500 m） are mainly kerogen thermal degradation gas, oil-cracking gas, and coal-type gas.

关键词： Genetic types Natural gases Jiyang Depression Light hydrocarbon properties Carbon isotope ratios Identification factors