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Preparation of sol-gel derived microcrystalline corundum abrasives with hexagonal platelets

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 71-75页

作者： Na li Yu-Mei Zhu Kai Gao zhi-hong li Key Laboratory of Advanced Ceramics and Machining Technology School of Materials Science and Engineering Tianjin University

The effects of different additives on the mechanical properties, microstructures, and wear behavior of corundum abra- sives were investigated. When the number of additive phases increases, the sintering temperature and wear rate decrease, while the densification and mechanical properties increase. The additive SiO2 is responsible for the development of equiaxed grains, whereas both CaO and MgO promote the development of platelike grains. By controlling the molar ratio of additives, it is pos- sible to obtain different microstructures. With SiO2-MgO-CaO （molar ratio, 2：1：1） as the additives and nano a-Al203 powders as the seed, microcrystalline corundum abrasives with hexagonal platelets were obtained using sol-gel process by sintering at 1300℃ for 0.5 h. The average diameter and thickness of hexagonal platelets are 1.38 μm and 360 nm respectively, the sin- gle-particle compressive strength is 26.44 N, and the wear rate is （3.06±=0.21）× 10^-7 mm^3/（N.m）.

关键词： additives corundum microcrystals sol-gel process platelets compressive strength wear

Preparation of large-area isotopic magnesium targets for the 25Mg(p,γ)^26 Al experiment at JUNA

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Nuclear Science and Techniques 2020年第9期31卷 75-81页

作者： Chen Chen Yun-Ju li Hao Zhang zhi-hong li School of Physics Zhengzhou UniversityZhengzhou 451400China China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 101408China

To study the 25Mg(p,y)^26 Al reaction at the Jinping Underground Nuclear Astrophysics laboratory,a large-area 25Mg target with a uniform thickness is needed.A rotating unit is used to ensure the uniformity of the target thickness during *** many attempts,19 targets with diameters of 40 mm and a non-uniformity of8.4%were prepared *** rate of material utilization was approximately 4.7 times higher than that obtained using a conventional evaporation method.

关键词： Vacuum evaporation Substrate rotation Uniformity Material utilization

Diversity of bacteria in different life stages and their impact on the development and reproduction of Zeugodacus tau(Diptera:Tephritidae)

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Insect Science 2021年第2期28卷 363-376页

作者： MdShibly Noman Ge Shi li-Jun liu zhi-hong li Department of Entomology MOA Key Lab of Pest Monitoring and Green ManagementCollege of Plant ProtectionChina Agricultural UniversityBeijingChina

Fruit flies usually harbor diverse communities of bacteria in their digestive systems,which are known to play a significant role in their ***,little information is available on Zeugodacus tau,a polyphagous pest *** study reports the first extensive analysis of bacterial communities in different life stages and their effect on the development and reproduction of laboratory-reared Z *** bacteria were identified using the conventional method and all bacteria were identified by highthroughput technologies(16S ribosomal RNA gene sequencing of V3-V4 region).A total of six bacterial phyla were identified in larvae,pupae,and male and female adult flies,which were distributed into 14 classes,32 orders,58 families and 96 *** was the most represented phylum in all the stages except ***,Klebsiella,Providencia,and Pseudomonas were identified by conventional and next-generation sequencing analysis in both male and female adult flies,and Enterobacter was found to be the main *** being fed with antibiotics from the first instar larvae,bacterial diversity changed markedly in the adult *** flies laid eggs and needed 20 days before oviposition while the treated flies showed ovary development inhibited and were not able to lay eggs,probably due to the alteration of the *** findings provide the cornerstone for unexplored research on bacterial function in Z tau,which will help to develop an environmentally friendly management technique for this kind of harmful insect.

关键词： antibiotics bacterial diversity fitness oviposition symbiotic bacteria Zeugodacus tau

A New Furostanol Glycoside from Polygonatum odoratum

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Chinese Chemical Letters 2003年第12期14卷 1259-1260页

作者： Hai lin QIN zhi hong li Peng WANG Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050

A new furostanol component glycosylated only at C-26 was isolated from the rhizomes of Polygonatum odoratum (Mill.) Druce, and its structure was characterized as 22-hydroxy-25(R and S) furost-5-en-12-on-3b, 22, 26-tri... 详细信息

关键词： Polygonatum odoratum (Mill.) Druce furostanol monoglycoside.

Genetic relationship of the melon fly, Bactrocera cucurbitae （Diptera： Tephritidae）inferred from mitochondrial DNA

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Insect Science 2012年第2期19卷 195-204页

作者： Yi Wu Bruce A.McPheron Jia-Jiao Wu zhi-hong li Department of Entomology College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingChina Department of Entomology Penn State UniversityUniversity ParkPAUSA Guangdong Entry-Exit Inspection and Quarantine Bureau Guangzhou Environment and Plant Protection Institute Chinese Academy of Tropical Agricultural SciencesHainanChina

The melon fruit fly, Bactrocera cucurbitae （Coquillett）（Diptera： Tephritidae）, has been the subject of worldwide quarantine and management efforts due to its widespread agricultural impact and potential for rapid range expansion. From its presumed native distribution in India, this species has spread throughout the hot-humid regions of the world. We provide information that reveals population structure, invasion history and population connectivity from 23 locations covering nine countries based on DNA sequences of the mitochondrial cytochrome oxidase I （COI） gene. Forty-two polymorphic sites were described among 38 haplotypes. The most common haplotype, H1, was observed in 73% of the samples distributed among all populations. Highest genetic diversity was seen within populations, and no isolation-by-distance was detected. The western regions （Nepal, Bangladesh, Thailand, Burma and China-west） showed higher haplotype diversity than eastern regions （China-east）. China-Yunnan showed highest levels of genetic diversity in China. Haplotype diversity decreased with longitude from west to east. Together, these analyses suggest that B. cueurbitae has expanded from west to east within a limited geographic scale and recently invaded China through Yunnan Province.

关键词： Bactrocera cucurbitae mitochondrial haplotypes population expansion population structure

Tailored lithium metal/polymer electrolyte interface with liTa_(2)PO_(8) fillers in PEO-based composite electrolyte

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Rare Metals 2022年第8期41卷 2826-2833页

作者： Bing Huang zhi-hong li Yu-Mei Zhu Yong Che Chang-An Wang Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin300072China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Enpower Energy Corp. Beijing102600China

The unstable li/PEO-based electrolyte interface in allsolid-state lithium metal batteries usually leads to high interfacial resistance,low Coulombie efficiency and fast lithium dendrites growth even under a low current *** interface composition directly determines the interfacial integrity,dynamic li^(+)/e^(-)transport processes and the subsequent li+plating/stripping behavior;thus,it is of significance to regulate the interphase to have better safety and higher energy density for all-solid-state lithium metal ***,by incorporation of li^+conducting liTa_(2) PO_(8) fillers in PEO-based polymer electrolyte.

关键词： electrolyte lithium interface

New determination of the^7Be ground state spectroscopic factor and the^6li(p,γ)^7Be astrophysical S(E)factors

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Chinese Physics C 2018年第6期42卷 110-113页

作者： zhi-hong li Er-Tao li Jun Su Yun-Ju li You-Bao Wang Sheng-Quan Yan Bing Guo Ding Nan Wei-Ping liu China Institute of Atomic Energy Beijing 102413China College of Physics and Energy Shenzhen UniversityShenzhen 518060China

The ＇lithium problem, in Big Bang nucleosynthesis（BBN） has recently focused on reactions involving ^7 *** ^6 li（p,γ）^7 Be reaction can provide us not only with information about ^6 li destruction but also with information about ^7 Be production. In the present work, the proton spectroscopic factor in ^7 Be is extracted to be 0.70 ± 0.17 from the angular distribution of ^7 Be（d, ^3 He）^6 li at Ec.m. = 6.7 MeV. This value is then used to compute the direct component of the astrophysical ^6 li（p,γ）^7 Beg.s. S（E） factors and determine the resonance parameters from the total S（E） factors.

关键词： big bang nucleosynthesis spectroscopic factor proton radioactive capture reaction

Double Slag Operation Dephosphorization in BOF for Producing Low Phosphorus Steel

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Journal of Iron and Steel Research International 2009年第3期16卷 6-14页

作者： TIAN zhi-hong li Ben-hai ZHANG Xiao-ming JIANG Zhong-hang Shougang Research Institute of Technology Shougang Group Beijing 100041 China

A study on the production of low phosphorus steel by double slag operation in 210 t converter was carried out. A phosphorus content of less than 0.005% （mass percent） was obtained before tapping. About 80% phosphorus could be removed by the first slag after 5 min. High Fe^3＋ content and high basicity in the first slag were in favor of dephosphorization. On the other hand,Fe3＋ content had less effect on dephosphorization during second slag treatment. In the second slag period,the fraction of dephosphorization increased with the increase of basicity up to a basicity of 6. Further increase of basicity of the second slag had very little effect on dephosphorization. The tapping temperature had great impact on dephosphorization. It was impossible to get phosphorus less that 0.005% when the tapping temperature was higher than 1 943 K. The optimum operation conditions were suggested. On the basis of these conditions,the amount of the second slag and the effect of the remaining first slag were estimated.

关键词： dephosphorization double slag low phosphorus steel converter

Simple Scheme for Directly Measuring Concurrence of Two-Qubit Pure States in One Step

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Communications in Theoretical Physics 2009年第2期51卷 252-254页

作者： YANG Rong-Can liN Xiu HUANG zhi-Ping li hong-Cai School of Physics and Opto-Electronics Technology Fujian Normal University Fuzhou 350007 China

In the present work, a simple scheme for the direct measurement of the concurrence of two-qubit pure states is proposed. The scheme is based on trapped ions and only needs one step when the two identical pure states are given. The vibrational mode in our proposal is only virtually excited, which is important in view of ***, the scheme is feasible based on current technologies.

关键词： concurrence trapped ions measurement one step