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Morphology control of magnetic properties in cobalt nanowires

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Rare Metals 2023年第6期42卷 1994-1999页

作者： Huan-Huan Xu Qiong Wu Ming Yue Cheng-lin li hong-jian li College of Materials Science and Engineering Beijing University of TechnologyBeijing100124China

Cobalt nanowires with different shapes and sizes were synthesized by reduction of carboxylate salts of Co^(Ⅱ) in 1,2-butanediol using a solvothermal chemical *** well-crystallized Co nanowires with hexagonal closepacked(hep) phase are observed and the(002) crystalline direction is along the long axis of nano *** morphology control is strongly dependent on the reaction *** varying the amount of capping agent in proper ranges,the effect of reaction parameters on controlling the size and shape of Co nanowires is *** the amount of capping agent increasing,the aspect ratio of Co nanowires increases ***,the magnetic measurement of cobalt nanowires shows that the coercivity of the Co nanocrystals does not increase with the increase in aspect ratio monotonously,which suggests that the tip shape and micros tructure also play an important role in the magnetization reversal process of the Co nanocrystals,and the aspect ratio plays a much less role as the ratio value exceeds *** further understand the effect of size on the magnetic properties in the Co nanowires,micromagnetic simulations were performed,which confirms that the magnetic properties are barely affected by the aspect ratio larger than *** highest coercivity of624 kA·m^(-1) is obtained for ellipsoid nano wires with a mean length of 200 nm,which also displays a strong magnetic *** a result,the highest energy product of the wires reaches 248 kJ·m^(-3).

关键词： Co nanowires Morphology control Tip shape High energy product

Current susceptibilities of brown planthopper Nilaparvata lugens to triflumezopyrim and other frequently used insecticides in China

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Insect Science 2021年第1期28卷 115-126页

作者： Xun liao Peng-Fei Xu Pei-Pan Gong Hu Wan jian-hong li nstitute of Crop Protection Guizhou UniversityGuiyangChina Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina

The brown planthopper is a notorious rice pest in many areas of *** evolution of insecticide resistance in Nilaparvata lugens has become a serious problem in the effective control of this pest in the paddy *** this article,the current susceptibility of *** field populations to novel mesoionic insecticide triflumezopyrim and major classes of chemical insecticides was determined and *** monitoring results indicated that field populations of *** had developed low resistance to triflumezopyrim(resistance ratio,RR:1.3-7.3-fold)during 2015-2018 in China,and the median lethal concentration values varied from 0.05 to 0.29 mg/***,during 2017 to 2018,field populations of *** showed high resistance levels to thiamethoxam(RR:456.1-1025.6-fold),imidacloprid(RR:2195.3-6899.0-fold)and buprofezin(RR:1241.57521.7-fold),moderate to high resistance levels to dinotefuran(RR:97.6-320.1-fold),clothianidin(RR:69.4-230.1-fold)and isoprocarb(RR:44.1-108.0-fold),and low to moderate levels of resistance to chlorpyrifos(RR:12.0-29.7-fold)and nitenpyram(RR:6.9-24.1-fold).In contrast,*** just showed low resistance to sulfoxaflor(RR:3.3-8.5-fold)and etofenprox(RR:5.0-9.1-fold)in the ***,the P450 gene CYP6ER1 was found to be significantly overexpressed in all five field populations of *** collected in 2018 when compared with a laboratory susceptible *** findings will provide useful information to delay the evolution of insecticide resistance in ***.

关键词： Nilaparvata lugens(Stal) P450 gene susceptibility triflumezopyrim

Molecular design,synthesis and biological activities of amidines as new ketol-acid reductoisomerase inhibitors

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Chinese Chemical Letters 2008年第6期19卷 651-654页

作者： Bao Lei Wang Yong hong li jian Guo Wang Yi Ma Zheng Ming li Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

Diamidine （A） was identified in our in vitro bio-assay as a possible inhibitor of ketol-acid reductoisomerase （KARI） from the ACD database search based on the known three-dimensional crystal structure of KARI. An investigation on interaction of A on KARI active sites, led to the design and synthesis of 15 novel monoamidines. Some of those showed better biological activity than A on rice KARI （in vitro） and in greenhouse herbicidal tests （in vivo）. The structure-biological activity relationship was investigated, which provides valuable information to further study of potential KARI inhibitors.

关键词： KARl Molecular design Synthesis Biological activity

Structure and magnetic properties of nanocrystalline dysprosium powders

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Rare Metals 2020年第1期39卷 28-35页

作者： hong-jian li Qiong Wu Ming Yue Yu-Qing li Rong-Chun Zhu Jing-Ming liang Jiu-Xing Zhang College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing100124China

In this current study,nanocrystalline Dy powders were prepared by melt-spinning and subsequent highenergy *** effect of ball-milling time on the structure and magnetic properties of the powders was *** crystal structure and microstructure of the melt-spun ribbons and ball-milled powders were observed by X-ray diffraction(XRD),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Magnetic measurement of all samples was performed with vibrating sample magnetometer(VSM).XRD results indicate that the average crystal grain size of the powders decreases from 90.09 nm of the ribbons to 10.42 nm of the4-h ball-milled *** TEM observation shows that the grains are fine and *** Neel temperature(TN)decreases from 182 K of the ribbons to 172 K of the powders,while the Curie temperature(TC)increases from100 to 130 K,demonstrating that the grain size has substantial influence on the magnetic transition ***,at 60 K,as the ball-milling time increases,the coercivity of the powders increases first,peaking at 0.48 T for 2-h milling,then drops again,while the remanence of the powders decreases monotonic *** a result,the powders milled for 2 h exhibit an optimal maximum energy product of 64.0 kJ·m-3,demonstrating the good potential of these powders as a permanent magnet at low temperatures.

关键词： Dysprosium Nanocrystalline Low temperature Magnetic properties

A de novo transcriptomic analysis to reveal functional genes in Apolygus lucorum

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Insect Science 2016年第1期23卷 2-14页

作者： De-Pan Cao Yang liu Jin-Jin Wei jian-hong li Gui-Rong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Laboratory of Pesticide College of Plant Science & Technology Huazhong Agricultural University Wuhan China

The widespread planting of genetically engineered cotton producing the CrylAc toxin has led to significantly reduced pesticide applications since 1997. However, conse- quently, the number of green mirid bugs （GMB）, Apolygus lucorum （Meyer-Diir） has in- creased. So far the GMB, instead of the cotton bollworm Helicoverpa armigera （Hiibner）, has become the major pest in the transgenic Bt cotton field and has influenced cotton yield. Disproportionately, only a few studies on GMB at molecular level have been re- ported. libraries from both third instar nymphs and adults were sequenced using Illumina technology, producing more than 106 million short reads and assembled into 63 029 uni- genes of mean length 597 nt and N50 813 nt, ranging from 300 nt to 9771 nt. BLASTx analysis against Nr, Swissprot, GO and COG was performed to annotate these unigenes. As a result, 26 478 unigenes （42.01%） matched to known proteins and 107 immune-related, 320 digestive-related and 53 metamorphosis-related genes were detected in these annotated unigenes. Additionally, we profiled gene expression using mapping based differentially expressed genes （DEGs） strategy between the two developmental stages： nymph and adult. The results demonstrated that thousands of genes were significantly differentially ex- pressed at different developmental stages. The transcriptome and gene expression data provided comprehensive and global gene resources of GMB. This transcriptome would improve our understanding of the molecular mechanisms of various underlying biological characteristics, including development, digestion and immunity in GMB. Therefore, these findings could help elucidate the intrinsic factors of the GMB resurgence, offering novel pest management targets for future transgenic cotton breeding.

关键词： Apolygus lucorum digestion immunity metamorphosis transcriptome

In Vitro Construction of Effective M1GS Ribozymes Targeting HCMV UL54 RNA Segments

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 210-214页

作者： Yun-Zhen SU hong-jian li Yue-Qin li Hao-Jun CHEN Dong-Sheng TANG Xin ZHANG hong jianG Tian-hong ZHOU College of life Science and Technology,Jinan University,Guangzhou 510632,China College of life Science and Technology Jinan UniversityGuangzhou 510632 China

Seven sequence-specific ribozymes(M1GS RNAs)derived in vitro from the catalytic RNAsubunit of Escherichia coli RNase P and targeting the mRNAs transcribed by the UL54 gene encoding theDNA polymerase of human cytomegalovirus were screened from 11 ribozymes that were designed based onfour rules:(1)the NCCA-3′ terminal must be unpaired with the substrate;(2)the guide sequence(GS)mustbe at least 12 nt in length;(3)the eighth nucleotide must be U,counting from the site-1;and(4)around thecleavage site,the sites-1/+1/+2 must be U/G/C or C/G/*** investigation of the factors affecting thecleavage effect and the optimal ratio for M1GS/substrate was carried *** was determined that the optimalratio for M1GS/substrate was 2:1 and too much M1GS 1ed to substrate *** indicated *** M1GS that cleaved HCMV UL54 RNA segments in vitro were successfully designed and *** studies support the use of ribozyme M1GS as antisense molecules to silence HCMV mRNA in vitro,andusing the selection procedure as a general approach for the engineering of RNase P ribozymes.

关键词： ribonuclease P (RNase P) guide sequence HCMV DNA polymerase

Microwave absorption properties of Ag naowires/carbon black composites

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Chinese Physics B 2017年第2期26卷 349-356页

作者： Hai-Long Huang Hui Xia Zhi-Bo Guo Yu Chen hong-jian li School of Physics and Electronics Central South University Changsha 410083 China

The composite that can absorb the high-performance electromagnetic（EM） wave is constructed into a sandwiched structure composed of carbon black（CB）/ethylene-vinyl acetate（EVA） and Ag naowires（Ag NWs）. The Ag NWs sandwiched between two CB/EVA layers are used to improve the absorption properties of composite. The effects of EVA-to-CB weight ratio, concentration and diameter of Ag NWs with a thickness of 0.4 mm on microwave absorption are *** results indicate that for an EVA-to-CB weight ratio of 1：3, Ag NW concentration of 1.0 mg/100 m L, and average diameter of 56 nm, the reflection loss（RL） of the composite is below-10 d B in a frequency range of 9.3 Ghz–18.0 GHz, with the minimum values of-40.0 d B and-25.6 d B at 13.5 GHz and 15.3 GHz, respectively. A finite element method（FEM）is used for calculating the RL of the composite. The calculated results are in agreement with the experimental data.

关键词： microwave absorption sliver nanowires finite element method polymer-based composites

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun Fu hong-Wei li jian-hong Shi Tan li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Technological Characters and Improvements on Type SLC-S Precalciner Kiln

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Journal of Wuhan University of Technology(Materials Science) 2001年第2期16卷 69-72页

作者：胡曙光 Wuhan University of Technology Wuhan 430070 China

In this paper the problems on SP kiln period is discussed, whichlead to low CaCO_3 decarbon- ation rate in the hot meal, so that kilncoating is vulnerable and material frequently falls off and blocksthe pre- heater. Excellent effects are achieved when skipping the SPkiln period, neglecting the function of the dividing gate below theC4 preheater and sending the material completely into the calciner.

关键词： precalciner character improvement