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Development of samarium–cobalt rare earth permanent magnetic materials

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Rare Metals 2014年第6期33卷 633-640页

作者： jian-hong Yi Faculty of Materials Science and Engineering Kunming University of Science and Technology

Samarium–cobalt rare-earth（Sm–Co-RE） permanent magnetic materials with large magnetic energy product, high coercive force, high Curie temperature, good thermal stability, and corrosion resistance, have wide potential applications in aerospace, microwave communications, instrumentation, electrical engineering, magnetic machinery, etc. In this paper, the development of Sm–CoRE permanent magnetic materials in the following aspects in recent years was summarized： Sm–Co-RE permanent magnets with high application temperatures, positive temperature coefficients of coercive force, zero temperature coefficients of residual magnetization, high resistance rate,high mechanical property, and nanocrystallization.

关键词： Samarium–cobalt rare-earth permanent magnet Magnetic Temperature coefficient Resistivity

Diverged Copies of the Seed Regulatory Opaque-2 Gene by a Segmental Duplication in the Progenitor Genome of Rice, Sorghum, and Maize

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Molecular Plant 2008年第5期1卷 760-769页

作者： jian-hong Xu Joachim Messing Waksman Institute of Microbiology Rutgers University 190 Frelinghuysen Road Piscataway NJ 08854 USA

Comparative analyses of the sequence of entire genomes have shown that gene duplications, chromosomal segmental duplications, or even whole genome duplications （WGD） have played prominent roles in the evolution of many eukaryotic species. Here, we used the ancient duplication of a well known transcription factor in maize, encoded by the Opaque-2 （O2） locus, to examine the general features of divergences of chromosomal segmental duplications in a lineagespecific manner. We took advantage of contiguous chromosomal sequence information in rice （Oryza sativa, Nipponbare）, sorghum （Sorghum bicolor, Btx623）, and maize （Zea rnays, B73） that were aligned by conserved gene order （synteny）. This analysis showed that the maize 02 locus is contained within a 1.25 million base-pair （Mb） segment on chromosome 7, which was duplicated ≈56 million years ago （mya） before the split of rice and maize 50 mya. The duplicated region on chromosome I is only half the size and contains the maize OHP gene, which does not restore the O2 mutation although it encodes a protein with the same DNA and protein binding properties in endosperm. The segmental duplication is not only found in rice, but also in sorghum, which split from maize 11.9 mya. A detailed analysis of the duplicated regions provided examples for complex rearrangements including deletions, duplications, conversions, inversions, and translocations. Furthermore, the rice and sorghum genomes appeared to be more stable than the maize genome, probably because maize underwent allotetraploidization and then diploidization.

关键词： WGD Opaque-2

Gravitational Equivalence Theorem and Double-Copy for Kaluza-Klein Graviton Scattering Amplitudes

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Research 2022年第4期2022卷 411-420页

作者： Yan-Feng Hang hong-jian He Tsung-Dao Lee Institute and School of Physics and Astronomy Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologyShanghai Jiao Tong UniversityShanghaiChina Institute of Modern Physics and Department of Physics Tsinghua UniversityBeijingChina Center for High Energy Physics Peking UniversityBeijingChina

We analyze the structure of scattering amplitudes of the Kaluza-Klein (KK) gravitons and of the KK gravitational Goldstone bosons in the compactified 5d general relativity (GR). Using a general Rξ gauge fixing, we study the geometric Higgs mechanism for the massive spin-2 KK gravitons. We newly propose and prove a gravitational equivalence theorem (GRET) to connect the scattering amplitudes of longitudinal KK gravitons to that of the KK gravitational Goldstone bosons, which formulates the geometric gravitational Higgs mechanism at the scatteringS-matrix level. We demonstrate that the GRET provides a general energy cancellation mechanism guaranteeing the N-point longitudinal KK graviton scattering amplitudes to have their leading energy dependence cancelled down by a large power factor of E^(2N)(N≥4) up to any loop level. We propose an improved double-copy approach to construct the massive KK graviton (Goldstone) amplitudes from the KK gauge boson (Goldstone) amplitudes. With these, we establish a new correspondence between the two types of energy cancellations in the four-point longitudinal KK amplitudes at tree level: E^(4)→E0 in the KK gauge theory and E^(10)→E^(2) in the KK GR theory.

关键词： theory gauge guarantee

Analysis of dipole-like ultra high frequency RFID tags close to metallic surfaces

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1217-1222页

作者： Ling-fei MO hong-jian ZHANG hong-liang ZHOU State Key Lab of Industrial Control Technology Department of Control Zhejiang University Hangzhou 310027 China

It is a challenge for passive RFID tags to be mounted on the surface of metal because the parameters of tag antennas,such as the impedance matching,the radiation efficiency and the radiation pattern,are seriously affected by the metallic *** paper presents the characteristics of the dipole-like antennas of ultra high frequency(UHF) radio frequency identification(RFID) tags that are placed close to metallic *** finite element method(FEM) and method of moment(MoM) were used to simulate the changes of the antenna parameters near the metallic *** typical dipole-like antennas close to the metallic surface,a closed loop antenna and a loaded meander antenna,were modeled,and the performance was *** was carried out and the results were in good agreement with the simulation,showing that a distance of 0.05λ～0.1λ(λ is the free space wavelength) from the metallic surface could make the dipole-like UHF RFID tag performance be acceptable.

关键词： Radio frequency identification (RFID) Tag Metallic surface Finite element method (FEM) Method of moment (MoM)

Creating multiferroic and conductive domain walls in common ferroelastic compounds

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npj Computational Materials 2019年第1期5卷 332-338页

作者： hong jian Zhao JorgeÍñiguez Materials Research and Technology Department Luxembourg Institute of Science and Technology(LIST)Avenue des Hauts-Fourneaux 5L-4362 Esch/AlzetteLuxembourg Physics and Materials Science Research Unit University of LuxembourgRue du Brill 41L-4422 BelvauxLuxembourg Physics Department and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA

Domain walls in ferroelectrics and ferroelastics often present peculiar functional properties,offering an intriguing route toward the design of *** we use first-principles simulations to illustrate an approach for engineering such walls,working with representative ferroelastic perovskites LaGaO_(3) and CaTiO_(3)(insulating,non-magnetic,non-polar).We show that a wide range of substitutional dopants can be used to create long-range-ordered structures confined within the walls of these compounds,yielding functional interfaces with tailor-made *** thus identify clear-cut strategies to produce metallic walls within an insulating ***,we find ways to create magnetic walls that also display ferroelectric order(proper or improper),thus providing an original route to obtain magnetoelectric *** the recent developments on the preparation of high-density domain structures in perovskite films,our results suggest a definite path toward new functional nano-materials.

关键词： properties. walls perovskite

Effect of Initial Concentration on Adsorption-Desorption Characteristics and Desorption Hysteresis of Hexachlorobenzene in Soils

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Pedosphere 2010年第1期20卷 104-110页

作者： GAO hong-jian jianG Xin School of Resources and Environmental Science Anhui Agricultural University Hefei 230036 (China) State Key Lab of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

Adsorption and desorption are important processes that influence the transport, transformation, and bioavailability of hexachlorobenzene (HCB) in soils. To examine the adsorption-desorption characteristics of HCB, equilibrium batch experiments were carried out using two soils (red soil and paddy soil) with different initial HCB concentrations (0.25, 0.50, 0.75, 1.00, 1.50, 2.50, 3.50, and 5.00 mg L-1 ) by using 0.01 mol L-1 calcium chloride as the background solution. The successive desorption experiments (48, 96, 144, 192, and 240 h) were conducted after each adsorption equilibrium experiment. The results revealed that adsorption and desorption isotherms of HCB on two soils were nonlinear, which can be best described by the Freundlich equation with the square of the correlation coefficient (r 2 ) ranging from 0.97 to 0.99. Desorption of HCB from the two soils exhibited hysteresis at all HCB concentrations because the Freundlich desorption coefficients were always higher than the Freundlich adsorption coefficients. The hysteretic effect was enhanced with increasing initial HCB concentration, and positive hysteresis was observed at different concentrations.

关键词： Freundlich equation sorption coefficients sorption isotherms

Adjuvant therapy for hepatocellular carcinoma:Dilemmas at the start of a new era

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World Journal of Gastroenterology 2024年第8期30卷 806-810页

作者： jian-hong Zhong Department of Hepatobiliary Surgery Guangxi Medical University Cancer HospitalNanning 530021Guangxi Zhuang Autonomous RegionChina

Approximately 50%-70%of patients with hepatocellular carcinoma experience recurrence within five years after curative hepatic resection or *** a result,many patients receive adjuvant therapy after curative resection or ablation in order to prolong recurrence-free *** therapy recommended by national guidelines can differ,and guidelines do not specify when to initiate adjuvant therapy or how long to continue *** and other unanswered questions around adjuvant therapies make it difficult to optimize them and determine which may be more appropriate for a given type of *** questions need to be addressed by clinicians and researchers.

关键词： Adjuvant therapy Hepatocellular carcinoma Tumor recurrence Unanswered questions

Highly Sensitive Spectrofluorimetric Determination of Trace Amounts of Indium(Ⅲ) with Salicylaldehyde Salicyloylhydrazone

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Chemical Research in Chinese Universities 2002年第2期18卷 183-188页

作者： HAN Fang WANG hong jian TANG Bo Department of Chemistry Shandong Normal UniversityJinan 250014P.R.China

The fluorescent reaction of salicylaldehyde salicyloylhydrazone(SASH) with indium(Ⅲ) was studied in detail. Based on this chelation reaction, a sensitive spectrofluorimetric method was developed for the determination of indium in a water ethanol(volume ratio 3∶7) medium at pH 4 0. Under the condition, the In SASH complex displays an excitation and emission maxima at 396 and 461 nm, respectively. The linear range of the method is from 4 7 to 1000 ng/mL and the detection limit is 0 94 ng/mL. The molar ratio of indium to the reagent is 1∶1. The interferences of other ions were studied. The method was successfully applied to the determination of indium in the chemical reagents of lead, tin, zinc, zinc chloride and geological samples by standard addition method.

关键词： Indium determination Salicylaldehyde salicyloylhydrazone Spectrofluorimetry

Probing new physics in dimension-8 neutral gauge couplings at e^+e^-colliders

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Science China(Physics,Mechanics & Astronomy) 2021年第2期64卷 2-26页

作者： John Ellis hong-jian He Rui-Qing Xiao Department of Physics Kings College LondonStrandLondonWC2R 2LSUK Theoretical Physics Department CERNCH-1211Geneva 23Switzerland NICPB Rävala 10Tallinn10143Estonia Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Key Laboratory for Particle Physics and CosmologyShanghai Jiao Tong UniversityShanghai200240China Institute of Modern Physics and Department of Physics Tsinghua UniversityBeijing100084China Center for High Energy Physics Peking UniversityBeijing100871China

Neutral triple gauge couplings(nTGCs)are absent in the standard model effective theory up to dimension-6 operators,but could arise from dimension-8 effective *** this work,we study the pure gauge operators of dimension-8 that contribute to nTGCs and are independent of the dimension-8 operator involving the Higgs *** show that the pure gauge operators generate both ZγZ^*and Zγγ^*vertices with rapid energy dependence∝E^5,which can be probed sensitively via the reaction e^+e^-→Zγ.We demonstrate that measuring the nTGCs via the reaction e^+e^-→Zγfollowed by Z→qq decays can probe the new physics scales of dimension-8 pure gauge operators up to the range(1-5)TeV at the CEPC,FCC-ee and ILC colliders with s~(1/2)=(0.25-1)TeV,and up to the range(10-16)TeV at CLIC with s~(1/2)=(3-5)TeV,assuming in each case an integrated luminosity of 5 ab~(-1).We compare these sensitivities with the corresponding probes of the dimension-8 nTGC operators involving Higgs doublets and the dimension-8 fermionic contact operators that contribute to the e^+e^-Zγvertex.

关键词： neutral triple gauge couplings new physics beyond the standard model effective field theory e^+e^-colliders