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Statistical properties of radio flux densities of solar flares

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Research in Astronomy and Astrophysics 2020年第11期20卷 239-251页

作者： Lu Wang Si-Ming Liu zong-jun Ning purple Mountain Observatory Nanjing 210000China Key Laboratory of Dark Matter and Space Astronomy Nanjing 210000China University of Science and Technology of China Heifei 100049China

Short timescale flux variations are closely related to the energy release process of magnetic reconnection during solar *** light curves at 1,2,3.75,9.4,and 17 GHz of 209 flares observed by the Nobeyama Radio Polarimeter from 2000 to 2010 are analyzed with a running smooth *** find that the impulsive component(with a variation timescale shorter than 1 s)of 1 GHz emission of most flares peaks at a few tens of solar flux unit and lasts for about 1 minute and the impulsive component of 2 GHz emission lasts a shorter period and peaks at a lower flux level,while at the three high frequency channels the occurrence frequency of flares increases with the decrease of the flux density up to the noise level of the corresponding ***,the gradual components of these emissions have similar duration and peak flux density *** also derive the power spectrum on different timescales and a normalized wavelet analysis is used to confirm features on short *** a time resolution of 0.1 s,more than^60%of these radio light curves show significant flux variation on 1 s or shorter time *** fraction increases with the decrease of frequency and reaches^100%at 1 GHz,implying that short timescale processes are universal in solar *** also study the correlation between the impulsive radio flux densities and soft X-ray fluxes obtained with the GOES satellites and find that more than 65%of the flares with an impulsive component have their impulsive radio emission reach a peak value ahead of the soft X-ray fluxes and this fraction increases with the radio frequency.

关键词： methods data analysis Sun flares Sun radio radiation

Synergistic regulation of drought-responsive genes by transcription factor OsbZIP23 and histone modification in rice

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Journal of Integrative Plant Biology 2020年第6期62卷 723-729页

作者： Wei zong jun Yang Jie Fu Lizhong Xiong National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China

Thousands of differentially expressed genes(DEGs)have been identified in rice under drought stress ***,the regulatory mechanism of these DEGs remains largely ***,we report an interplay between histone H3K4me3 modification and transcription factor Osb ZIP23 in the regulation of a dehydrin gene cluster under drought stress conditions in *** the H3K4me3 modification level was increased,the dehydrin gene expression levels were increased,and the binding levels of Osb ZIP23 to the promoter of the dehydrin genes were also ***,the H3K4me3 modification and dehydrin gene expression levels were downregulated in the osbzip23 mutant under drought stress *** study uncovers a collaboration between transcription factor and H3K4me3 modification in the regulation of droughtresponsive genes,which will help us to further understand the gene regulation mechanism under stress conditions in plants.

关键词： responsive conditions. drought

The effect of prophylactic antibiotics in acute upper gastrointestinal bleeding patients in the emergency department

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World Journal of Emergency Medicine 2023年第6期14卷 442-447页

作者： Miao Gan Liang zong Xuezhong Yu jun Xu Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China

BACKGROUND: Currently, prophylactic antibiotics are recommended only for cirrhotic patients with acute upper gastrointestinal bleeding(AUGIB);however, the benefit for other AUGIB patients remains undetermined. We aimed to compare the clinical outcomes between patients with AUGIB with and without prophylactic antibiotics to identify the population that requires this ***: Patients with AUGIB admitted between 1st January 2019 and 31st December 2021 in the Emergency Department of Peking Union Medical College Hospital were enrolled. Patients were divided into the antibiotic and non-antibiotic groups. The primary outcome was in-hospital mortality, and the secondary outcome was the onset of new infection. The risk factors for mortality and infection were analyzed, and stratification analysis of prophylactic antibiotics was performed. Continuous data were analyzed using the t-test or nonparametric rank sum test, and categorical data were analyzed using the Chi-square test or Fisher's exact test. Indicators with significant differences between the groups were included for logistic regression analysis. A P-value <0.05 was considered statistically significant. RESULTS: A total of 392 individuals were included, among them, 281 patients received prophylactic antibiotics, and 111 patients did not receive prophylactic antibiotics. The mortality rates were significantly lower in the antibiotic group than in the non-antibiotics group(6.41% vs. 17.12%, P=0.001). The risk factors for infection were varicose veins(P=0.045) and endotracheal intubation(P=0.005) in the prophylactic antibiotic group, and endoscopic treatment(P=0.010) in the non-prophylactic antibiotic group. Stratified analyses showed that patients with age ≥ 65 years, endotracheal intubation, endoscopic treatment, and AUGIB of variceal etiologies benefited from prophylactic ***: AUGIB patients may benefit from prophylactic antibiotics to decrease mortality, especially those aged ≥ 65 years a

关键词： Acute upper gastrointestinal bleeding Prophylactic antibiotics Stratification

Interfacial microstructure and mechanical properties of stainless steel clad plate prepared by vacuum hot rolling

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Journal of Iron and Steel Research International 2018年第7期25卷 732-738页

作者： jun Jiang Hua Ding zong-an Luo Guang-ming Xie School of Materials and Metallurgy Northeastern University Shenyang 110819 Liaoning China Shenyang Aircraft Corporation Shenyang 110034 Liaoning China State Key Laboratory of Roiling and Automation Northeastern University Shenyang 110819 Liaoning China

A stainless steel clad plate composed of stainless steel and carbon steel was prepared by vacuum hot rolling process, and its microstructure, especially the bonding interface, was evaluated using an optical microscope, a scanning electron micro- scope and a transmission electron microscope （TEM）. The corresponding mechanical properties were also assessed by means of hardness and shear tests. The results showed a bonding interface formed between stainless steel and carbon steel, which was relatively straight in macroscope but serrated in microscope. Decarburization layer and carbon-enriched layer were distinguished at the side of carbon steel and stainless steel near the interface, respectively, which should be related to diffusion of carbon and alloying elements. The carbon-enriched layer could also be identified as a recombination region, whose microstructure was mainly recognized as martensite by TEM. Consequently, the hardness was the highest at this region. Furthermore, the result of shear test at the bonding interface showed that the shear strength was 395 MPa and the fracture mode was dominated as ductile fracture, indicating the bonding interface with good quality.

关键词： Stainless steel clad plate Vacuum hot rolling Interface microstructure Mechanical property

A novel variable topology design for a multi-flexible ejection mechanism

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Defence Technology（防务技术） 2020年第2期16卷 432-438页

作者： Hao Liu jun Zhou zong-lai Mo Shi-wei Zhang School of Astronautics Northwestern Polytechnical UniversityXi'an710072China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Luoyang Opto-Electro Technology Development Center 471009China

The airborne missile launch mechanism often subjects to significant deformations induced by the large ejection force during high-speed actuations in missile ejection process,leading to a substantial deviation of separation parameters from designed values that threats safety of the *** study proposes a novel variable topology design for launch mechanism,achieved via a Prsmatic-Revolute-Revolute pair(PR-R)motion formed by the structural gap with a specific *** enables launch mechanism variability during missile ejection process and optimizes the ejection force given by the front and back ejection arms,and greatly optimizes the separation parameters during missile *** kinetics simulation analysis is conducted under working conditions of the original ejection mechanism and the novel mechanism with variable topology design,*** results show that the novel variable topology design is more befitting for the launch process in terms of system safety and controllability,effectively improving the separation posture,restraining the flexible effect of the mechanism,and fulfilling the effectiveness of the design value of multi-rigid body.

关键词： Variable topology Gap dynamics Multi-flexible body Flexible control Ejection mechanism

Positron Impact Ionization of Hydrogen, Sodium, and Potassium

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Chinese Physics Letters 1997年第5期14卷 348-351页

作者： ZHOU Ya-jun PAN Shou-pu Institute of Atomic and Molecular Physics National Laboratory of Theoretical and Computational ChemistryJilin UniversityChangchun 130023

The total ionization cross sections for positron scattering by hydrogen,sodium,and potassium are calculated by applying an equivalent-local optical potential model from the ionization threshold to *** total ionization cross sections are in excellent agreement with the recent measurements of Jones et *** total ionization cross sections for sodium and potassium are compared with other theoretical calculations.

关键词： potassium ionization applying

Experimental and numerical investigations on wave motions over platform reef-flat

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Journal of Hydrodynamics 2022年第2期34卷 244-258页

作者： Hong-jun Zhao Liu-jun zong Cheng-ji Shen jun Kong Yu-liang Zhu jun-da Wang College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing210024China Hohai University Key Laboratory of Coastal Disasters and Defence Ministry of EducationNanjing210024China

Previous studies have shown that high-frequency(HF)waves,low-frequency(LF)waves and wave set-up coexist on shallow coral reef-flat and jointly contribute to potential floods and subsequent damages of infrastructures and islands on *** better understand the reef-flat wave dynamics with incident waves and still water level,a wave-flume experiment was performed based on an idealized platform reef composed of a steep reef-face(1:4),a relatively mild reef-rim(1:14)and a horizontal ***,the non-hydrostatic phase-resolving model SWASH was validated against the experiment and then applied to further numerically investigate the effects of reef-rim topographic features on the reef-flat wave *** results show that incident waves of a larger wave height and a longer wave period can generate larger LF waves and wave set-up,thereby inducing greater HF waves on the *** still water level can lead to larger HF waves but result in smaller wave *** contrast to HF waves and wave set-up,LF waves are minimally affected by the still water level.A rim of milder slope and larger edge depth will induce smaller HF and LF waves and set-up on the reef-flat,and thus provide better protection for the reef-flat ***,on the reef-flat,the ratio of HF significant wave height to water depth H_(s_h)/(h_(r)+η^(-))is approximately constant;the dimensionless LF significant wave height Hs_l/H_(s0) and the dimensionless wave set-upη^(-)/[T_(p)(gH_(s0))1/2]can be related to the inverse wave steepness parameter gT_(p)^(2)/H_(s0) and the relative reef-flat submergence(h_(r)+η^(-))/H_(s0) respectively.

关键词： High-frequency waves low-frequency waves wave set-up platform reef reef-rim topographic features

High-gravity-assisted green synthesis of rare-earth doped calcium molybdate colloidal nanophosphors

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1744-1751页

作者： Yuan pu Lifeng Lin jun Liu Jiexin Wang Dan Wang State Key Laboratory of Organic Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

In this work,we report an innovative route for the synthesis of rare-earth doped calcium molybdate(CaMoO4)nanophosphors by using high gravity rotating packed bed(RPB)technology and paraffin liquid as the *** significant intensified mass transfer and micromixing of reactants in the RPB reactor are benefiting for homogeneous doping of rare-earth ions in the host materials,leading to nanophosphors with high quantum *** use of liquid paraffin as the solvent eliminates the safety risks associated with volatile organic compounds,increasing the potential for clean production of *** excitation of deep ultraviolet(DUV)light,the CaMoO4:Na+,Eu3+nanophosphors exhibit red emission at peak wavelength of 615 nm and quantum yield of up to 35.01%.The CaMoO4:Na+,Tb3+nanophosphors exhibit green emission at peak wavelength of543 nm with quantum yield of up to 30.66%.The morphologies of the nanophosphors are tunable from nanofibers through nanorods to nanodots and the possible mechanism of controlling the formation of different nanostructures is proposed on the basis of experimental results and theoretical analysis of *** nanophosphors are highly dispersible in organic solvents and utilized for fabricating fabrication of flexible,freestanding luminescent films based on silicone *** also demonstrate the red LEDs consisting of the hybrid films of CaMoO4:Na+,Eu3+nanoparticles as color-converting phosphors and DUV LEDs as illuminators,offering strong potential for future nanophosphors-basedsolid-state lighting systems.

关键词： Colloidal nanophosphors CaMoO4 Process intensification High gravity technology Green solvent

Periocular skin“tattooing”caused by gel pen pigment mistaken for periorbital bruising:a case of missed diagnosis of traumatic intraorbital pen core foreign body

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 366-369页

作者： Chao Xiong Zhang-jun Ren Xue-Mei Li Jin-Hai Yu Yue Li Yun-Xiu Chen Qi Jin Ze-Xi Sang Si-Yi Wang An-An Wang pu-Ying Gan Qi-Hua Xu Yao-Hua Wang Hong-Fei Liao Department of Orbital Diseases Tumor and Ocular TraumaThe Affiliated Eye HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330000Jiangxi ProvinceChina

Dear Editor,We are writing this letter to report a special missed diagnosis case of pediatric ocular trauma with intraorbital pencil core foreign *** an eye trauma occurs,orbital foreign bodies are *** most common typ... 详细信息

关键词： diagnosis foreign letter