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Enhancing hydrogen storage performance via optimizing Y and Ni element in magnesium alloy

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Journal of Magnesium and Alloys 2022年第3期10卷 888-903页

作者： xu pang Lei Ran Yu'an Chen Yuxiao Luo Fusheng Pan College of materials Science and engineering Chongqing UniversityChongqing 400044China National Engineering Research for magnesium Alloys Chongqing UniversityChongqing 400044China Guangdong Guoyan Science and Technology Research Center Co. LtdGuangdong 518000China

Magnesium-based hydrogen storage materials are considered as one of the most promising candidates for solid state hydrogen storage due to their advantages of high hydrogen capacity,excellent reversibility and low *** this paper,Mg_(91.4)Ni_(7)Y_(1.6) and Mg_(92.8)Ni_(2.4)Y_(4.8) alloys were prepared by melting and ball *** microstructures and phases were characterized by X-ray diffraction,scanning electron microscope and transmission electron microscope,and hydrogen absorbing and desorbing properties were tested by the high pressure gas adsorption apparatus and differential scanning calorimetry(DSC).In order to estimate the activation energy and growth mechanism of alloy hydride,the JMAK,Arrhenius and Kissinger methods were applied for *** hydrogen absorption content of Mg_(92.8)Ni_(2.4)Y_(4.8) alloy reaches 3.84 wt.%within 5 min under 350℃,3 MPa,and the maximum hydrogen capacity of the alloy is 4.89 wt.%in same ***,the hydrogen absorption of Mg_(91.4)Ni_(7)Y_(1.6) alloy reaches 5.78 wt.%within 5 min,and the maximum hydrogen absorption of the alloy is 6.44 wt.%at 350℃and 3 *** hydrogenation activation energy of Mg_(94.4)Ni_(7)Y_(1.6) alloy is 25.4 kJ/mol H_(2),and the enthalpy and entropy of hydrogen absorption are-60.6 kJ/mol H_(2) and 105.5 J/K/mol H_(2),*** alloy begins to dehydrogenate at 210℃,with the dehydrogenation activation energy of 87.7 kJ/mol H_(2).By altering the addition amount of Ni and Y elements,the 14 H-LPSO phase with smaller size and ternary eutectic areas with high volume fraction are obtained,which provides more phase boundaries and catalysts with better dispersion,and there are a lot of fine particles in the alloy,these structures are beneficial to enhance the hydrogen storage performance of the alloys.

关键词： Hydrogen storage materials LPSO phase Catalytic effect Hydrogen storage performance

Changes of matrix metalloproteinases in the stroma after corneal cross-linking in rabbits

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International Journal of Ophthalmology(English edition) 2021年第1期14卷 26-31页

作者： Hong-Zhen Jia xu pang Xiu-Jun Peng Department of Ophthalmology the Sixth Medical Center of Chinese PLA General HospitalBeijing 100048China

AIM:To observe changes in the content of matrix metalloproteinases(MMPs)in the corneal stroma after corneal cross-linking(CXL)in rabbits,and further explore the corneal pathophysiological process after ***:Forty-two rabbits(42 eyes)were randomly divided into seven *** group served as the control group,while the other six groups were treated with *** concentrations of MMPs in corneal stroma were evaluated through parallel reaction monitoring at baseline and 3,7,15,30,90,and 180 d after ***:The levels of MMP-2 in the corneal stroma of rabbits were 0.76±0.07,2.78±1.39,4.12±0.69,2.00±0.29,2.00±0.30,1.22±0.18,and 1.35±0.18(10^(-9)mol/g)at baseline and 3,7,15,30,90,and 180 d after treatment,*** contents of tissue inhibitor of metalloproteinase-1(TIMP-1)were 1.83±0.26,7.94±0.58,6.95±2.64,3.81±0.48,3.07±0.92,1.72±0.19,and 1.69±0.74(10^(-9)mol/g),*** ratios of MMP-2/TIMP-1 were 0.42±0.33,0.36±0.20,0.62±0.10,0.54±0.15,0.68±0.13,0.71±0.10,and 0.68±0.09,*** CXL,the expression of MMP-2 and TIMP-1 in the rabbit corneal stroma was initially increased and subsequently *** levels of MMP-2 remained higher than those recorded at baseline 180 d after treatment,but it was not statistically *** levels of TIMP-1 returned to baseline levels at 90 d after *** ratio of MMP-2/TIMP-1 started to rise from 7 d after *** was significantly higher than that calculated at baseline 30-180 d after *** results for MMP-1,-3,-7,-9,-13,and TIMP-2 were ***:CXL can lead to changes in the content of MMP-2 and TIMP-1 in the rabbit corneal *** ratio of MMP-2/TIMP-1 remains higher versus baseline,indicating that MMP-2 is involved in the corneal pathophysiological process after CXL.

关键词： corneal cross-linking keratoconus rabbit riboflavin matrix metalloproteinase

Controlling oxygen content in electro-slag remelting steel by optimizing slag-steel reaction process

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China Foundry 2023年第6期20卷 503-510页

作者： Dian-dong Sun Yong Wang Lei Jin Zong-xu pang Jian Huang Jian-ping Zhang Iron&Steel Research Institutes of Ansteel Group Corporation Anshan 114009LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009LiaoningChina Shenyang Research Institute of Foundry Co. Ltd.CAMNational Key Laboratory of Advanced Casting TechnologiesShenyang 110022China

The thermodynamic equilibrium of deoxidation reactions between molten slag and steel was calculated using a slag-steel coupling thermodynamic model and the mass conservation model based on the ion-molecular coexistence *** study focused on the effects of slag composition and deoxidizer type on the oxygen content of low alloy steel during the electroslag remelting(ESR)*** measured and predicted values of the oxygen content in remelted ingots,and the contents of FeO and MnO in slags were compared and *** show that the measured content of total oxygen has a certain correlation with the trend of dissolved oxygen predicted by the model when using Ca-Si alloys as deoxidizer,but it is not correlated with the trend of dissolved oxygen predicted by the model when using Al as *** deoxidation mechanisms of Ca-Si and Al are ***-Si alloy directly reacts with FeO and MnO in slag to reduce the oxygen potential of slag,hence it can inhibit the transfer of oxygen from the slag to molten ***,when Al deoxidizer is used,the oxygen content in steel is mainly reduced through floating up the alumina *** to Al,utilizing Ca-Si alloy as a deoxidizer is more effective in reducing the oxygen content and the amount of inclusions in ESR ingot.

关键词： ion-molecular coexistence theory slag-steel reaction deoxidation electro-slag remelting

Two New Supramolecular Hybrids Based on Bi-capped Keggin {PMo12V2O42} Clusters and Transition Metal Mixed-organic-ligand Complexes

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Chemical Research in Chinese Universities 2015年第2期31卷 179-186页

作者： DUAN Weijie JIAO Shihui LIU xu CHEN Jinlei CAO xuan CHEN Yan xu Wei CUI Xiaobing xu Jiqing pang Guangsheng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changehun 130012 P. R. China

Two supramolecular compounds [Cu（imz）2][Cu（phen）（imz）]2{[Cu（phen）]2[PMo6^VIMo6^VV2^IVO42]}（1） and [Co2（2,2＇-bpy）4（C2O4）][Co（2,2＇-bpy）3][PMo7^VIMo5^VV2^IVO42]（2,2＇-bpy）0.5.H2O（2）（phen=1,10＇-phenanthroline, imz= imidazole, 2,2＇-bpy=2.2＇-bipyridine） have been synthesized hydrothermally and characterized by elemental analyses, infrared spectrum, UV-Vis, X-ray photoelectron spectroscopy（XPS）, electron spin resonance（ESR） spectra, thermogravimetry analyses and single crystal X-ray diffraction analyses. Single-crystal X-ray diffraction analyses revealed that both the compounds represent the examples of compounds based on the bi-capped Keggin polyoxoanion {PMo12V2O42} and transition metal mixed-organic-ligand coordination complexes. Compound 1 consists of bi-capped Keggin polyoxoanion [PMo12V2O42]5 supported copper coordination groups, which are further interconnected with two types of copper complex fragments forming a 3D supramolecular framework via π-π stacking, C-H…O and N-H…-O hydrothermal bonding interactions. Compound 2 is a new hybrid consisted of polyoxoanion [PMo12V2O42]^4-, [Co2（2,2＇-bpy）4（C2O4）]^2＋ and [Co（2,2＇-bpy）3]^2＋. There are no direct interactions in compound 2, but the polyoxoanions together with two different cobalt complex groups construct a 3D supramolecular network through C-H…O hydrogen bonding interactions.

关键词： Transition metal mixed-organic-ligand complex Keggin polyoxometalate Hydrogen bond π-π Stackinginteraction

Riboflavin concentration in corneal stroma after intracameral injection

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 470-475页

作者： Na Li Xiu-Jun Peng Zheng-Jun Fan xu pang Yu Xia Teng-Fei Wu Chinese PLA Medical School & Chinese PLA General Hospital Department of Ophthalmology Navy General Hospital of Chinese PLA

AIM: To evaluate the enrichment of riboflavin in the corneal stroma after intracameral injection to research the barrier ability of the corneal endothelium to riboflavin in ***: The right eyes of 30 New Zealand white rabbits were divided into three groups. Different concentrations riboflavin-balanced salt solutions(BSS)were injected into the anterior chamber(10 with 0.5%, 10 with 1%, and 10 with 2%). Eight corneal buttons of 8.5mm in diameter from each group were dissected at 30 min after injection and the riboflavin concentrations in the corneal stroma were determined using high-performance liquid chromatography(HPLC) after removing the epithelium and endothelium. The other two rabbits in every group were observed for 24 h and sacrificed. As a comparison, the riboflavin concentrations from 16 corneal stromal samples were determined using HPLC after instillation of 0.1% riboflavin-BSS solution for30 min on the corneal surface(8 without epithelium and 8with intact epithelium).RESULTS: The mean riboflavin concentrations were11.19, 18.97, 25.08, 20.18, and 1.13 μg/g for 0.5%, 1%, 2%,de-epithelialzed samples, and the transepithelial groups,respectively. The color change of the corneal stroma and the HPLC results showed that enrichment with riboflavin similar to classical de-epithelialized corneal collagen crosslinking(CXL) could be achieved by intracameral 1%riboflavin-BSS solution after 30min; the effect appeared to be continuous for at least 30 ***: Riboflavin can effectively penetrate the corneal stroma through the endothelium after an intracameral injection in vivo, so it could be an enhancing method that could improve the corneal riboflavin concentration in transepithelial CXL.

关键词： riboflavin cornea intracameral injection high-performance liquid chromatography endothelium

Iontophoresis-assisted corneal crosslinking using 0.1% riboflavin for progressive keratoconus

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 717-722页

作者： Hong-Zhen Jia xu pang Zheng-Jun Fan Na Li Gang Li Xiu-Jun Peng Chinese PLA Medical School Beijing 100853 China Department of Ophthalmology Chinese PLA Navy General Hospital Beijing 100048 China

AIM：To report the clinical results of iontophoresis-assisted epithelium-on corneal crosslinking（I-CXL） using 0.1% riboflavin in distilled water for progressive keratoconus. METHODS：In this prospective clinical study, we examined 94 eyes of 75 patients with progressive keratoconus who were treated with I-CXL using 0.1% riboflavin in distilled water. Best correct visual acuity（BCVA）, Scheimpflug tomography, corneal topography, anterior segment optical coherence tomography, intraocular pressure, and endothelial cell density were evaluated at baseline and 1, 3, 6, 12, and 24 mo after ***：After 24 mo I-CXL, compared to the level at baseline, BCVA significantly improved 0.14±0.07（P=0.010）; mean keratometry signifi cantly decreased 0.72±1.97（P=0.021）; maximum keratometry significantly reduced 2.30±5.01（P=0.014）; central keratoconus index significantly reduced 0.04±0.08（P=0.007）. The demarcation line was visible in 83.1% of eyes at 1mo after treatment, with a depth of 298.95±51.97 μm, and gradually indistinguishable. One eye had repeat treatment. Intraocular pressure and endothelial cell density did not change ***：I-CXL using 0.1% riboflavin halts keratoconus progression within 24 mo, resulting in a significant improvement in visual and topographic parameters. Moreover, the depth of the demarcation line is similar to that previously reported in standard epithelium-off CXL procedures.

关键词： corneal cross-linking iontophoresis keratoconus distilled water riboflavin

Iontophoresis-assisted versus standard corneal crosslinking for progressive keratoconus

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Annals of Eye Science 2017年第1期2卷 28-34页

作者： Hong-Zhen Jia xu pang Zheng-Jun Fan Xiu-Jun Peng Department of Ophthalmology Chinese PLA Navy General HospitalBeijing 100048China

Background:To compare the safety and efficacy of iontophoresis-assisted epithelial-on corneal crosslinking(I-CXL)using 0.1%riboflavin-distilled water solution with standard epithelium-off corneal crosslinking(S-CXL)for progressive ***:In a retrospective analysis,progressive keratoconus patients treated with I-CXL(17 eyes of 17 patients)or S-CXL(13 eyes of 13 patients)were *** patients were followed up at least 12 *** patients underwent detailed ophthalmologic examinations involving pre-and postoperative visual acuity,topographic parameters and ***-and postoperative complications were ***:No statistically significant differences were observed between the two groups at baseline with respect to visual acuity,age and thinnest corneal thickness(TCT).The postoperative decreases of K1 and Kmean in the S-CXL group represented statistically significantly better results than in the I-CXL group(t=2.093 and 2.123,P=0.046 and 0.043,respectively).Alterations of other parameters showed no significant differences between the two *** were no failure cases in the two ***:I-CXL using 0.1%riboflavin-distilled water solution provided effective treatment for progressive keratoconus at 12-month ***,the decreases of K1 and Kmean caused by I-CXL were less than those by *** treatment time,postoperative patient pain and risk of infection in I-CXL are all less than those in S-CXL,I-CXL is unable to completely replace S-CXL for progressive keratoconus temporarily.

关键词： Keratoconus corneal crosslinking iontophoresis riboflavin

New prenylated flavonoid glycosides derived from Epimedium wushanense byβ-glucosidase hydrolysis and their testosterone production-promoting effects

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Chinese Journal of Natural Medicines 2022年第9期20卷 712-720页

作者： SUN Xin-Guang pang xu LIANG Hai-Zhen ZHANG Jie WANG Bei LI Qi WANG Jie CHEN Xiao-Juan GUO Bao-Lin MA Bai-Ping Department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China

Six new prenylated flavonoid glycosides,including four new furan-flavonoid glycosides wushepimedoside A–D(1–4)and two new prenyl flavonoid derivatives wushepimedoside E–F(5–6),and one know analog epimedkoreside B(7)were isolated from biotransformation products of the aerial parts of Epimedium *** structures were elucidated according to comprehensive analysis of HR-MS and NMR spectroscopic data,and the absolute configurations were assigned using experimental and calculated electronic circular dichroism(ECD)*** regulatory activity of compounds 1–7 on the production of testosterone in primary rat Leydig cells were investigated,and 4 and 5 exhibited testosterone production-promoting *** docking analysis suggested that bioactive compounds 4 and 5 showed the stable binding with 3β-HSD and 4 also had good affinity with Cyp17A1,which suggested that these compounds may regulate testosterone production through stimulating the expression of the above two key proteins.

关键词： Epimedium wushanense Biotransformation Prenylated flavonoids Regulation on testosterone production

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电磁波集中器散射放大功能的应用与分析

电子与信息学报 2013年第2期35卷 468-473页

作者：庞旭东朱守正华东师范大学信息科学与技术学院上海200241

变换电磁学是近几年来电磁领域的研究热点。利用坐标变换方法,能够在一定程度上人为调控电磁波的传播路径,结合超材料技术,可以设计出多种具有奇特功能的新颖电磁器件。该文对一系列折线型坐标变换器件做了归纳总结,主要讨论了其中的电... 详细信息

变换电磁学是近几年来电磁领域的研究热点。利用坐标变换方法,能够在一定程度上人为调控电磁波的传播路径,结合超材料技术,可以设计出多种具有奇特功能的新颖电磁器件。该文对一系列折线型坐标变换器件做了归纳总结,主要讨论了其中的电磁波集中器;在此基础上从内置隐身飞机模型的散射截面角度进一步研究了电磁波集中器的散射放大功能及其在军事上的应用;最后对该器件参数极值及其归一化分布范围进行了详细的分析。

关键词：变换电磁学超材料集中器散射放大