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A room-temperature magnetic semiconductor from a Co-Fe-Nb-B metallic glass

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 94-99页

作者： Yu-Zhang jiao Dmitry VLouzguine-Luzgin ke-Fu Yao Zheng-Jun Zhang Na Chen Laboratory for Advanced Materials Processing Technology(MOE) State Key Laboratory of New Ceramics and Fine ProcessingSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China key Laboratory for Advanced Materials(MOE) Schoolof Materials Science and EngineeringTsinghua UniversityBeijing 100084China Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan Mathematics for Advanced Materials-OIL National Institute of Advanced Industrial Science and Technology(AIST)Sendai 980-8577Japan

Magnetic semiconductors with Curie temperatures higher than room temperature show potential for developing spintronic devices with combined data processing and storage functions for next-generation computing *** this study,we present an n-type Co_(19.8)Fe_(8.6)Nb_(4.3)B_(6.0)O_(61.3) magnetic semiconductor with a high Curie temperature of~559 *** magnetic semiconductor has a room-temperature resistivity of~2.10×10^(4)Ωcm and a saturation magnetization of~76 emu/cm^(3).The n-type Co_(19.8)Fe_(8.6)Nb_(4.3)B_(6.0)O_(61.3)magnetic semiconductor was deposited on p-type silicon to form a heterojunction,exhibiting a rectifying *** results provide the design principles for discovering high Curie temperature magnetic semiconductors with determined conduction types,which would play an essential role in realizing nonvolatile spin-based transistors that break free from the confines of currently established Si-based information technology.

关键词： magnetic semiconductor ferromagnetic metallic glass high Curie temperature

AMPHIPHILIC STAR-BLOCK COPOLYMERS BY IODIDE-MEDIATED RADICAL POLYMERIZATION

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Chinese Journal of Polymer Science 2007年第6期25卷 609-619页

作者： Bing-yi Li Yan Shi Zhi-feng Fu Wan-tai Yang Shu-ke jiao State key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Amphiphilic star-block copolymers composed of polystyrene and poly（acrylic acid） were synthesized by iodide- mediated radical polymerization. Firstly, free radical polymerization of styrene was carried out with AIBN as initiator and 1,1,1-trimethyolpropane tri（2-iodoisobutyrate） as chain transfer agent, giving iodine atom ended star-shaped polystyrene with three arm chains, R（polystyrene）3. Secondly, tert-butyl acrylate was polymerization using polystyrene obtained as macro-chain transfer agent, and star-block copolymer, R（polystyrene-b-poly（tert-butyl acrylate））3 with controlled molecular weight was obtained. Finally, amphiphilic star-block copolymer, R（polystyrene-b-poly（acrylic acid））3 was obtained by hydrolysis of R（polystyrene-b-poly（tert-butyl acrylate））3 under acidic condition.

关键词： Living radical polymerization Iodide-Mediated radical polymerization Star-block copolymers Amphiphilic copolymers.

Synthesis of Highly Branched Poly(ε-caprolactone) by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

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Chinese Chemical Letters 2006年第3期17卷 373-376页

作者： Rui Xue LIU Yan SHI Zhi Feng FU Shu ke jiao key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029

Branched poly（ε-capmlactone） was synthesized by self-condensing atom transfer radical polymerization of macroinimer, α-acryloyoxy-ω-2-bromopropionyloxy poly（ε-caprolactone）, which was prepared by enzyme-catalyzed ring-opening polymerization of ε-caprolactone with 2-hydroxylethyl acrylate as initiator and esterification of the ω-hydroxyl group of the obtained poly（ε-caprolactone） by 2-bromopropionyl bromide.

关键词： Self-condensing vinyl polymerization atom transfer radical polymerization branched polymers poly(ε-caprolactone).

Strain-tunable electronic and optical properties of h-BN/BC_(3)heterostructure with enhanced electron mobility

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Chinese Physics B 2021年第7期30卷 425-432页

作者： Zhao-Yong jiao Yi-ran Wang Yong-Liang Guo Shu-Hong Ma School of Physics Henan Normal UniversityXinxiang 453007China School of Science Henan Institute of TechnologyXinxiang 453003China

By using first-principles calculation,we study the properties of h-BN/BC_(3)heterostructure and the effects of external electric fields and strains on its electronic and optical *** is found that the semiconducting h-BN/BC_(3)has good dynamical stability and ultrahigh stiffness,enhanced electron mobility,and well-preserved electronic band structure as the BC_(3)***,its electronic band structure is slightly modified by an external electric *** contrast,applying an external strain can mildly modulate the electronic band structure of h-BN/BC_(3)and the optical property exhibits an apparent redshift under a compressive strain relative to the pristine *** findings show that the h-BN/BC_(3)hybrid can be designed as optoelectronic device with moderately strain-tunable electronic and optical properties.

关键词： heterostructure electronic and optical properties first-principles calculation

The chemical treatments combined with antagonistic yeast control anthracnose and maintain the quality of postharvest mango fruit

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Journal of Integrative Agriculture 2019年第5期18卷 1159-1169页

作者： SHAO Yuan-zhi ZENG jiao-ke TANG Hong ZHOU Yi LI Wen College of Food Science Hainan University College of Horticulture Hainan University

During the storage and transportation of the mango fruit, the major source of disease is anthracnose, caused by the fungus Colletotrichum gloeosporioides. The objective of this study is to find an appropriate method that not only reduces mango decay but also maintains its postharvest quality. The effects of chemicals, the use of the yeast species Metschnikowia pulcherrima and their combination on storage quality, focusing on the enzyme activity related to disease of Tainong mangos was studied. By immersing the mangoes in M. pulcherrima suspension(1.0×10~8 cfu mL^(–1)), salicylic acid(SA) solution(50 mg L^(–1)) or calcium chloride(CaCl_2) solution(1.0 g L^(–1)), the lesion expansion and decay of the mango fruit caused by C. gloeosporioides could be significantly delayed. These treatments also delayed the changes in quality traits(a~* value, firmness, contents of total soluble solids(TSS) and vitamin C(Vc), while the activities of anti-disease enzymes such as polyphenol oxidase(PPO), phenylalanine ammonia lyase(PAL), chitinase(CHT) and β-1,3-glucanase(GUN) were enhanced as compared to the control treatment. Furthermore, the combination of SA solution, CaCl_2 solution and M. pulcherrima suspension presented an additive effect, increasing the efficacy in controlling the disease and maintaining the storage quality of mango fruits. Taken together, our data suggest that the integration of chemical treatments combined with M. pulcherrima could be an alternative to the use of fungicides in postharvest treatment of the mango fruit, specifically for improving storage quality as well as the control of the anthracnose.

关键词： mango fruit Metschnikowia pulcherrima Colletotrichum gloeosporioides storage quality enzyme activity

Enhanced aromatic selectivity by the sheet-like ZSM-5 in syngas conversion

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Journal of Energy Chemistry 2019年第8期28卷 44-48,I0003页

作者： Junhao Yang ke Gong Dengyun Miao Feng jiao Xiulian Pan Xiangju Meng Fengshou Xiao Xinhe Bao State key Laboratory of Catalysis National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of SciencesZhongshan Road 457 Dalian 116023 Liaoning China University of Chinese Academy of Sciences Yuquan Road 19A Shijingshan District Beijing 100049 China Department of Chemistry Zhejiang UniversityTianmushan Road 148 Xihu District Hangzhou 310028 Zhejiang China

Aromatics are important basic chemicals. However, direct conversion of syngas via the conventional Fischer-Tropsch synthesis produces little aromatics. We presented herein that a bifunctional composite of ZSM-5 in combination with Zn Cr Oxcatalyzes syngas conversion to aromatics. Particularly, ZSM-5 crystals with a sheet-like morphology can enhance significantly the aromatization activity. The lower length ratio of the b/a axes of the crystals, the more aromatics form but without influencing the selectivity of small molecules such as CH4 and C2–C4. Since the acid properties and the Al chemical environment were not altered while the morphology changed, the enhanced aromatic selectivity is likely attributed to the favored diffusion of aromatics in these sheet-like crystals.

关键词： Synthesis gas Aromatics Bifunctional OX-ZEO catalyst Zeolite Morphology

Primary logistics planning of oil products under the imbalance of supply and demand

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Petroleum Science 2022年第4期19卷 1915-1925页

作者： Rui Qiu Yong-Tu Liang Qi Liao Ying-Qi jiao Bo-Hong Wang Yi Guo Hao-ran Zhang National Engineering Laboratory for Pipeline Safety/Beijing key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China School of Petrochemical Engineering and Environment Zhejiang Ocean UniversityZhoushan316022China Sustainable Process Integration Laboratory–SPIL NETME CentreFaculty of Mechanical EngineeringBrno University of Technology–VUT BrnoTechnická2896/261669BrnoCzech Republic Oil&Gas Pipeline Control Center PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China Center for Spatial Information Science The University of Tokyo5-1-5 KashiwanohaKashiwa-shiChiba277-8568Japan

This paper intends to complete the primary logistics planning of oil products under the imbalance of supply and demand. An integrated mathematical programming model is developed to simultaneously find the balance between supply and demand, and optimize the logistics scheme. The model takes minimum logistics cost and resource adjustment cost as the objective function, and takes supply and demand capacity, transportation capacity, mass balance, and resource adjustment rules as *** adjustment rules are considered in the model, including resource adjustment within oil suppliers,within oil consumers, and between oil consumers. The model is tested on a large-scale primary logistics of a state-owned petroleum enterprise, involving 37 affiliated refineries, 31 procurement departments,286 market depots and dedicated consumers. After the unified optimization, the supply and demand imbalance is eased by 97% and the total cost is saved by 7%, which proves the effectiveness and applicability of the proposed model.

关键词： Oil product logistics Supply and demand imbalance Petroleum enterprise Resource adjustment Mathematical Programming model

Effect of Pre-deformation on Nanoscale Precipitation and Hardness of a Maraging Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2089-2100页

作者： Xinlei Zhou Bin Wang Tianyi Zeng Wei Yan Junhua Luan Wei Wang ke Yang Zengbao jiao School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Department of Materials Science and Engineering City University of Hong KongHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

The effect of pre-deformation on nanoscale precipitates and hardness of a maraging stainless steel strengthened by the coprecipitation of Ni_(3)Ti,Mo-enriched and Cr-enriched precipitates was systematically studied using electron back scattered diffraction,transmission electron microscopy and atom probe tomography(APT).Hardness measurements showed that the hardness of specimen with a deformation ratio of 90%peaked at HV 718 aged for 24 h,which is higher than that in the undeformed specimen(HV 603)aged for 72 h at 480℃.APT characterization revealed that pre-deformation could shorten the incubation time of the Mo-enriched and Cr-enriched *** the early-aged stage,pre-deformation increased the stain energy that inhibited the nucleation of Ni_(3)Ti precipitates,but accelerated the rejection of Mo from Ni-Ti ***,the strengthening model indicated that strain hardening(43%)makes a larger contribution to the hardness at the early-aged condition,while precipitation hardening(58%)has most contribution to the hardness at the peak-aged conditition.

关键词： Maraging stainless steel Pre-deformation Precipitation hardening Atom probe tomography

A new technology for treating waste incineration fly ash by shaft furnace

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Journal of Iron and Steel Research International 2021年第7期28卷 773-784页

作者： Cui Wang Long-zhi Chen Zheng-jian Liu Yang Li Yao-zu Wang ke-xin jiao State key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

At present,lots of municipal solid wastes(MSWs)are treated by incineration technology,which produces a large amount of fly ash that needs to be treated innocuously.A new method of using metallurgical shaft furnace to treat the MSW fly ash was thus proposed,and some research was done for this ***,the basic physical properties of MSW fly ash were analyzed,and then,the briquetting experiment and melting treatment of MSW fly ash were *** the process of briquet-ting,the influence of different factors(water content,cement content,forming pressure and curing time)on the compressive strength of the briquettes was *** results showed that with the increase in water content,cement content,forming pressure and curing time,the compressive strength of the briquettes increased ***,the compressive strength of the briquettes showed a downward trend when these values exceeded a specific *** the melting experiment,it was found that some heavy metals(such as Cr,Be and Ba)could be solidified in the slag when the fly ash was treated at 1450℃ for 50 min,and the leaching toxicity of heavy metals was lower than the landfill standard of waste in *** the same time,the decomposition rate of dioxins in fly ash reached 99.66%after melting treatment.

关键词： Fly ash Shaft furnace Compressive strength Melting treatment Heavy metal Dioxin