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XPS Analysis of the Passive Film Formed on 825 Nickel Based Alloy Lined Pipe

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稀有金属材料与工程 2012年第S1期41卷 256-259页

作者： zheng shuqi Chen Changfeng Zhou Chengshuang China Univ Petr Dept Mat Sci & Engn Beijing 102249 Peoples R China

The compositions and structures of the passive films formed on 825 nickel base alloy lined pipe serving for one year in an actual corrosion environment including 2.0 MPa H2S and 1.5 MPa CO2 at a temperature of 55℃were investigated by X-ray photoelectron spectroscopy(XPS).The results show that the passive films formed on 825 nickel base alloy is not destroyed even thicker than air-formed one and the films are composed of multilayer with different composition in each layer:an external part composed of a mixture of Cr and Ni oxide(more Ni included)and an inner part composed of a mixture of Cr and Ni oxide(Cr-rich layer).

关键词： nickel base alloy passive film XPS analysis

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Bi和Ag掺杂对SnTe热电性能的影响

人工晶体学报 2024年第3期53卷 526-533页

作者：高磊杨欣月李文浩王家宁刘瑞秀郑树启中国石油大学(北京)理学院能源交叉学科基础研究中心北京102249 中国石油大学(北京)理学院油气光学探测技术北京市重点实验室北京102249 中国石油大学(北京)新能源与材料学院北京102249

SnTe的晶体结构和能带结构与中温区性能最好的热电材料PbTe相似,因此作为PbTe的替代品被广泛研究。减小SnTe的轻重价带能量差和扩大带隙是优化SnTe热电性能的有效手段。本文通过Bi和Ag共同掺杂SnTe,使轻重价带能量差有效减小,带隙明显增... 详细信息

SnTe的晶体结构和能带结构与中温区性能最好的热电材料PbTe相似,因此作为PbTe的替代品被广泛研究。减小SnTe的轻重价带能量差和扩大带隙是优化SnTe热电性能的有效手段。本文通过Bi和Ag共同掺杂SnTe,使轻重价带能量差有效减小,带隙明显增大,获得了电运输性质提高的Sn_(1-2x)Bi_(x)Ag_(x)Te(x=0,0.01,0.02,0.03,0.04)样品。掺杂量x=0.03和0.04的Sn_(1-2x)Bi_(x)Ag_(x)Te样品相较于未掺杂的SnTe功率因数均有明显提升,其中,Sn_(0.94)Bi_(0.03)Ag_(0.03)Te样品的最大功率因子为15.34μW·cm^(-1)·K^(-2),与未掺杂的SnTe相比,提升了12.9%。Sn_(0.92)Bi_(0.04)Ag_(0.04)Te样品的最大功率因子为14.53μW·cm^(-1)·K^(-2)。同时,Bi和Ag共掺降低了SnTe的热导率,本研究得到Sn_(0.92)Bi_(0.04)Ag_(0.04)Te样品的总热导率明显低于未掺杂的SnTe,并且所有样品热导率都随温度升高而逐渐降低。在823 K时,Sn_(0.92)Bi_(0.04)Ag_(0.04)Te样品的总热导率降低为3.073 W·m^(-1)·K^(-1),其ZT值提升到了0.387。可见,对于提高SnTe热电性能,Bi和Ag共掺是一种有效策略。

关键词：热电材料 SnTe 热电性能能带工程第一性原理掺杂

Improvement of hydrogen permeation barrier performance by iron sulphide surface films

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1792-1800页

作者： Pengpeng Bai Shaowei Li Jie Cheng Xiangli Wen shuqi zheng Changfeng Chen Yu Tian State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Electronic&Information Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

Fe–S compounds with hexagonal crystal structure are potential hydrogen permeation barrier during H2S corrosion. Hexagonal system Fe–S films were prepared on carbon steel through corrosion and CVD deposition, and the barrier effect of different Fe–S films on hydrogen permeation was tested using electrochemical hydrogen permeation method. After that, the electrical properties of Fe–S compound during phase transformation were measured using thermoelectric measurement system. Results show that the mackinawite has no obvious barrier effect on hydrogen penetration, as a p-type semiconductor, and pyrrhotite (including troilite) has obvious barrier effect on hydrogen penetration,as an n-type semiconductor. Hydrogen permeation tests showed peak permeation performance when the surface was deposited with a continuous film of pyrrhotite (Fe_(1–x)S) and troilite. The FeS compounds suppressed hydrogen permeation by the promotion of the hydrogen evolution reaction, semiconducting inversion from p-to n-type, and the migration of ions at the interface.

关键词： hydrogen permeation barrier iron sulfide pyrrhotite semiconductor

乙烯和1-甲基环丙烯对椪柑采后浮皮及白皮层细胞壁代谢的影响

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浙江农林大学学报 2024年第2期41卷 234-242页

作者：王新胜张书凝柯甫志郑舒琪宫金礼孙学鹏张岚岚浙江农林大学园艺科学学院浙江省山区农业高效绿色生产协同创新中心/农业农村部亚热带果品蔬菜质量安全控制重点实验室浙江杭州311300 浙江省柑橘研究所浙江台州318020

【目的】浮皮是宽皮柑橘Citrus reticulata果实在成熟后期或采后储藏过程中普遍发生的一种生理性障碍。椪柑***‘Ponkan’在采后储藏中极易发生浮皮,严重影响商品价值。通过采后处理,为椪柑果实采后浮皮的防范、储藏保鲜技术提供理论依... 详细信息

【目的】浮皮是宽皮柑橘Citrus reticulata果实在成熟后期或采后储藏过程中普遍发生的一种生理性障碍。椪柑***‘Ponkan’在采后储藏中极易发生浮皮,严重影响商品价值。通过采后处理,为椪柑果实采后浮皮的防范、储藏保鲜技术提供理论依据。【方法】利用乙烯和1-甲基环丙烯(1-MCP)处理椪柑采后果实,测定椪柑在储藏期间果实主要品质指标及浮皮指数的变化,分析果皮白皮层细胞形态和生理变化特征。【结果】①乙烯处理促进了储藏期果实可溶性固形物质量分数的提高;加速了果皮白皮层细胞密度、纤维素质量分数、果胶质量分数的下降,促使木质素质量分数及细胞壁降解酶(纤维素酶、果胶酯酶、多聚半乳糖醛酸酶)活性上升。②1-MCP处理减缓了果皮白皮层细胞密度及纤维素质量分数下降;延缓了木质素质量分数及细胞壁降解酶(纤维素酶、果胶酯酶、多聚半乳糖醛酸酶)活性上升;减缓了椪柑果实浮皮指数的上升。【结论】乙烯处理可加速椪柑果实采后生理代谢水平,加重果实浮皮的发生。1-MCP处理可抑制储藏期果皮的生理代谢水平,减轻浮皮障碍的发生。生产中可通过乙烯和1-MCP处理来控制椪柑果实剥皮的难易程度。

关键词：椪柑果实采后品质浮皮乙烯 1-甲基环丙烯(1-MCP)

Defect engineering synergistically modulates power factor and thermal conductivity of CuGaTe2 for ultra-high thermoelectric performance

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Journal of Materials Science & Technology 2022年第33期128卷 213-220页

作者： Zipei Zhang Wenhao Li Lu Yu Sitong Wei Shikai Wei Zhen Ji Weiyu Song shuqi zheng State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China College of Science China University of PetroleumBeijing 102249China

The ternary chalcopyrite CuGaTe_(2)has emerged as a promising p-type thermoelectric material with its advantages of low cost,good stability,and non-toxic ***,its thermoelectric performance is limited by the intrinsic low electrical conductivity and high lattice thermal *** this work,A deficiency of Cu in Cu_(1–x)Ga Te_(2)semiconductors can be used to optimize the electrical properties by improving the carrier concentration and to reduce thermal conductivity through multi-scale phonon scattering,which is predicted and guided by the First-principles density functional theory *** carrier concentration is increased to 1020,which compensates for the low electrical performance caused by the intrinsic low nHof CuGaTe_(2).The average power factor of Cu_(0.96)Ga Te_(2)reaches 106.3%higher than that of the original CuGaTe_(2).In addition,the lattice thermal conductivity of the defective samples is greatly reduced at high temperatures,which is mainly due to the reduction of sound speed and phonon *** the above factors contribute to the highest dimensionless figure of merit(ZT)value of 1.23 at 823 K in Cu_(0.96)GaTe_(2),which is 114%higher than the pristine CuGaTe_(2),and the average ZT is 171.4%higher.

关键词： Thermoelectric CuGaTe_(2) Carrier concentration Thermal conductivity

我国杏和李子用农药登记情况及残留限量标准研究

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农药科学与管理 2024年第7期45卷 14-19页

作者：徐本秀张莹莹杨军军郑书旗北京市农林科学院林业果树研究所农业农村部果品及苗木质量检验测试中心(北京)

本研究基于中国农药信息网农药登记数据库中杏和李子的农药用药登记情况，结合食品安全标准《食品安全国家标准食品中农药最大残留限量》（GB 2763-2021）及其增补版《食品中2,4-滴丁酸钠盐等112种农药最大残留限量》（GB 2763.1-2022... 详细信息

本研究基于中国农药信息网农药登记数据库中杏和李子的农药用药登记情况，结合食品安全标准《食品安全国家标准食品中农药最大残留限量》（GB 2763-2021）及其增补版《食品中2,4-滴丁酸钠盐等112种农药最大残留限量》（GB 2763.1-2022）中关于农药种类和最大残留限量的相关指标，统计分析了杏和李子用农药登记情况和农药残留限量标准制定情况，以期为杏和李子的病虫害防治及产品质量安全提供有效参考，为安全生产提供技术保障，为完善农药登记管理提供科学依据。

关键词：杏李子农药登记最大残留限量

Enhanced thermoelectric performance in n-type Mg_(3.2)Sb_(1.5)Bi_(0.5) doping with lanthanides at the Mg site

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Journal of Materials Science & Technology 2022年第32期127卷 108-114页

作者： Lu Yu Zipei Zhang Juan Li Wenhao Li Shikai Wei Sitong Wei Guiwu Lu Weiyu Song shuqi zheng State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China College of Science China University of PetroleumBeijing 102249China

Mg-based thermoelectric materials have attracted more and more attention because of their rich composition elements,green environmental protection,and lower *** recent years,the thermoelectric properties of n-type Mg_(3)Sb_(2) materials have been optimized by doping chalcogenide elements(S,Se,and Te)at the anionic *** this work,n-type Mg_(3.2)A_(x)Sb_(1.5)Bi_(0.5)(A=Gd,Ho;x=0.01,0.02,0.03,and 0.4)samples were prepared by the cation site doping of lanthanide elements(Gd and Ho).The research results show that Gd and Ho doped n-type Mg3.2Sb1.5Bi0.5samples are entirely comparable to the S,Se,and Te doped n-type Mg3.2Sb1.5Bi0.5samples,demonstrating more excellent thermoelectric *** with lanthanides(Gd and Ho)at the Mg site increases the carrier concentration of the material to 8.161×10^(19)cm^(-3).Doping induces the contribution of more electron,thus obtaining higher *** maximum zT value of the Mg_(3.2)Gd_(0.02)Sb_(1.5)Bi_(0.5) and the Mg_(3.2)Ho_(0.02)Sb_(1.5)Bi_(0.5) samples reaches 1.61 and 1.55,*** work theoretically and experimentally demonstrates Gd and Ho are efficient n-type dopants for Mg_(3.2)Sb_(1.5)Bi_(0.5) thermoelectric material.

关键词： Thermoelectric material First-principles calculation Mg_(3.2)Sb_(1.5)Bi_(0.5)

Decoupling of thermoelectric transport performance of Ag doped and Se alloyed tellurium induced by carrier mobility compensation

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Journal of Materials Science & Technology 2022年第6期101卷 71-79页

作者： Yue Wu Xiaofan Zhang Boyi Wang Jingxuan Liang Zipei Zhang Jiawei Yang Ximeng Dong shuqi zheng Huai-zhou Zhao State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice ***,extra ionization impurity centers induced by Se alloying are harmful to the electric transport properties of the *** this paper,we propose that the incorporation of Ag could successfully compensate the lost carrier mobility(μH)due to Se alloying through the regulation of microstructure,resulting in the higher power factor(PF)than that of samples without *** composition optimization,theκLdecreased from 1.29 W m^(-1)K^(-1) of Te_(0.99)Sb_(0.01) to 1.05 W m^(-1)K^(-1) of Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01) at 350 K,while the PF remained unchanged or even slightly *** from the synergistic effect of carrier mobility compensation and phonon scattering,a maximum z T of 0.91 at 573 K and an average z T of 0.57(between 298 and 573 K)are achieved in Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01).This work presents a new strategy for decoupling the thermal and electric parameters of Te-based thermoelectric materials.

关键词： Te Ag doping Microstructure regulation Mobility compensation

Effect of Aging Temperature on Stress Corrosion Cracking of 17-4 PH Stainless Steel in Wet H_2S Environment

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稀有金属材料与工程 2012年第S1期41卷 219-222页

作者： Zhou Chengshuang,zheng shuqi,Chen Changfeng,Lu Guiwu China University of Petroleum,Beijing 102249,China China Univ Petr Dept Mat Sci & Engn Beijing 102249 Peoples R China

The effect of aging temperature on stress corrosion crocking of 17-4 precipitation-hardened(PH)stainless steel in simulated stimulant oil well environment was studied by the method B-NACE standard bent-beam *** is found that when aging temperature ranges from 480 to 610℃,the sensitivity of hydrogen embrittlement decreases significantly.

关键词： stress corrosion crocking(SSC) aging temperature 17-4 precipitation-hardened stainless steel hydrogen embrittlement