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Chinese Physics B 2020年第12期29卷 386-395页

作者： Bing Zhou Ya-Rong wang Ke Zheng Yong Ma Yong-sheng wang sheng-wang yu yu-Cheng Wu Institute of New Carbon Materials Taiyuan University of TechnologyTaiyuan 030024China

TiAl-based alloys have received extensive attention recently due to their excellent properties. However, the weak oxidation resistance at temperatures higher than 800℃ can limit their further high-temperature structural *** improve the oxidation resistance of a high-Nb-content γ-TiAl alloy(Ti-45 Al-8.5 Nb, in units of at.%), a chromium(Cr)coating is prepared by using the plasma surface alloying technique, separately, at 800℃ and 1000℃. The x-ray diffraction(XRD) patterns reveal that an oxide surface layer consisting of Cr2O3, Al2O3, and TiO2 is produced on the Cr-coated Nb containing γ-TiAl substrates during the initial oxidation. However, the Cr2O3 is dominated in the oxide surface layer after being isothermally oxidized for 300 h. The oxidation kinetic curves are composed of a parabolic law stage(≤ 90 h) and a biquadratic law stage(≥ 90 h), fit by weight–gain curves. Due to diffusion in the fabrication process and oxidation process,the Cr-coated specimens have an adhesion force after being isothermally oxidized, specifically 69 N for a specimen after oxidation for 300 h. These results demonstrate that the Cr coating enhances the oxidation resistance and adhesion of a Ti-45 Al-8.5 Nb alloy, which may provide a new feasible scheme for designing oxidation protection layers.

关键词： titanium aluminum alloy coating isothermal oxidation plasma surface alloying technique

Synthesis and antitumor activity of 9-methyl-10-hydroxycamptothecin

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Chinese Chemical Letters 2008年第8期19卷 918-920页

作者： sheng wang yu Yan Li Qi Dong You Department of Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A novel camptothecin analogue, 9-methyl-10-hydroxycamptothecin （4）, was unexpectedly synthesized from 10-hydroxycamptothecin in two steps. The key step included an efficient Mannich-type reaction. The overall yield was 47.2%. An ether analogue of 4, 9-methyl-10-benzylaminomethoxycamptothecin （5）, was also prepared. These new camptothecin analogues were evaluated for in vitro cytotoxicity against four human cancer cell lines, and exhibited more potent antitumor activities than contrals camptothecin and topotecan against several cancer cells.

关键词： Synthesis Camptothecin 10-Hydroxycamptothecin Cytotoxicity

Synthesis of carbosilane dendrimers with N,N-dimethylaniline as end groups

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Chinese Chemical Letters 2009年第3期20卷 300-301页

作者： Wen Yan Sun Deng Xu wang sheng yu Feng School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China

Carbosilane dendrimers with 4-bromo-N,N-dimethylaniline as end groups were synthesized from methyltfichlorosilane, aUyl chloride, magnesium and 4-bromo-N,N-dimethylaniline. All compounds were characterized by ^1H NMR,... 详细信息

关键词： Dendrimer Synthesis Carbosilane

Recurrent Seizures Manifestations in a Case of Congenital Hypoparathyroidism:a Case Report

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Chinese Medical Sciences Journal 2013年第4期28卷 242-244页

作者： sheng-yu wang Wei Wu Xuan Ma Internal Medicine Department Affiliated Hospital of Xi'an Medical University

HYPOPARATHYROIDISM is characterized by hypocalcemia, hyperphosphatemia and low or inappropriately normal levels of parathyroid hormone （PTH）. PTH is a key calcium regulatinghormone essential for calcium homeostasis, vitamin D-dependent calcium absorption, renal calcium reabsorption and renal phosphate clearance. Hypoparathyroidism may be due to congenital or acquired disorders. Causes include autoimmune diseases, genetic abnormalities, destruction or infiltrative disorders of the parathyroid glands.

关键词： hypoparathyroidism seizure basal ganglia calcification

A series of carbosilane dendrimers with acetyl end-group:From synthesis to their unique optical characteristics

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Chinese Chemical Letters 2009年第9期20卷 1085-1087页

作者： Wen Yan Sun Hai Feng Lu Deng Xu wang sheng yu Feng School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China

A series of c arbosilane dendrimers with acetyl end-group were synthesized. Their structures were characterized by 1H NMR, IR, and MS, respectively. Then dendrimers were coordinated with lanthanide ions （Eu3＋ and Tb3＋, respectively）. The luminescence spectra of the complexes show narrow-width emissions in visible light region. 2009 sheng yu Feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Synthesis Carbosilane dendrirner Luminescence Lanthanide ions

Conditions and Stimulation for Germination in Glycyrrhiza uralensis Fisch Seeds

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Agricultural Sciences in China 2008年第12期7卷 1438-1444页

作者： MAO Pei-sheng wang yu-hong wang Xin-guo LIAN Jia-jie HUANG Ying Forage Seed Lab China Agricultural University Beijing 100193 P.R.China

Evaluation of seed quality is the key to seed distributing and seeding of Glycyrrhiza uralensis Fisch, as an important species for pharmacy and soil conservation. Here, we study the effects of light and temperature on seed germination and mechanical and chemical scarification on breaking the seed coat. Seeds were collected in 2004, 2005, and 2006, placed in Petri dishes, and incubated at constant temperature 20, 25, and 30℃, and alternating temperature 15-25, 20-30, 15-30, and 20-35℃ under either an 8h photoperiod or total darkness for 28 consecutive days. Different methods were used to break the dormancy owing to hard seededness in this species such as chemical scarification by immersing in concentrated sulphuric acid for 5, 10, 15, 20, 25, 30, 45, and 60 min, in 0.2% KNO3 solution to saturate the seedbed, and prechilling for 7 d at 7℃ and mechanical scarification by cutting. The results showed that alternating temperature at 20-30℃ with 8 h photoperiod and 16 h darkness was optimum for G. uralensis seed germinating in the laboratory. Hard seeds were broken by concentrated sulphuric acid soaking or mechanical scarification by cutting. Germination of seeds harvested in two different years was both promoted by immersing for 30-45 min in concentrated sulphuric acid. KNO3 solution was ineffective for reducing hard seeds. During seed germinating, the first count was on the 7th day and the last count was on the 14th day.

关键词： seed germination seed hardness seed scarification Glycyrrhiza uralensis

Effect of metal nanoparticle doping concentration on surface morphology and field emission properties of nano-diamond films

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Chinese Physics B 2021年第6期30卷 617-624页

作者： Yao wang sheng-wang yu Yan-Peng Xue Hong-Jun Hei Yan-Xia Wu Yan-Yan Shen Institute of New Carbon Materials Taiyuan University of TechnologyTaiyuan 030024China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China

Nano-diamond particles are co-deposited on Ti substrates with metal(Ti/Ni) nanoparticles(NPs) by the electrophoretic deposition(EPD) method combined with a furnace annealing at 800℃ under N_(2) atmosphere. Modifications of structural and electron field emission(EFE) properties of the metal-doped films are investigated with different metal NPs concentrations. Our results show that the surface characteristics and EFE performances of the samples are first enhanced and then reduced with metal NPs concentration increasing. Both the Ti-doped and Ni-doped nano-diamond composite films exhibit optimal EFE and microstructural performances when the doping quantity is 5 mg. Remarkably enhanced EFE properties with a low turn-on field of 1.38 V/μm and a high current density of 1.32 mA/cm^(2) at an applied field of 2.94 V/μm are achieved for Ni-doped nano-diamond films, and are superior to those for Ti-doped ones. The enhancement of the EFE properties for the Ti-doped films results from the formation of the TiC-network after annealing. However, the doping of electron-rich Ni NPs and formation of high conductive graphitic phase are considered to be the factor, which results in marvelous EFE properties for these Ni-doped nano-diamond films.

关键词： diamond films metal doping electrophoretic deposition field emission properties

Global Impact and Balancing Act:Deciphering the Effect of Fluorination on B 1s Binding Energies in Fluorinated h‑BN Nanosheets

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Precision Chemistry 2024年第6期2卷 239-244页

作者： Yang Xiao Jun-Rong Zhang sheng-yu wang Weijie Hua MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Department of Applied PhysicsSchool of PhysicsNanjing University of Science and Technology210094 NanjingChina

X-ray photoelectron spectroscopy(XPS)is an important characterization tool in the pursuit of controllable fluorination of two-dimensional hexagonal boron nitride(h-BN).However,there is a lack of clear spectral interpretation,and seemingly conflicting measurements *** discern the structure−spectroscopy relation,we performed a comprehensive first-principles study on the boron 1s edge XPS of fluorinated h-BN(F-BN)*** gradually introducing 1−6 fluorine atoms into different boron or nitrogen sites,we created various F-BN structures with doping ratios ranging from 1 to 6%.Our calculations reveal that fluorines landed at boron or nitrogen sites exert competitive effects on the B 1s binding energies(BEs),leading to red or blue shifts in different *** calculations affirmed the hypothesis that fluorination affects 1s BEs of all borons in theπ-conjugated system,opposing the transferability from h-BN to ***,we observe that BE generally increases with higher fluorine concentration when both borons and nitrogens are nonexclusively *** findings provide critical insights into how fluorination affects boron’s 1s BEs,contributing to a better understanding of fluorination functionalization processes in h-BN and its potential applications in materials science.

关键词： X-ray photoelectron spectroscopy Core-electron binding energy Fluorination Hexagonal boron nitride Cluster-periodic method Born-Oppenheimer molecular dynamics

Landscape of s-triazine molecule on Si(100) by a theoretical x-ray photoelectron spectroscopy and x-ray absorption near-edge structure spectra study

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Chinese Physics B 2018年第11期27卷 437-444页

作者： Jing Hu Xiu-Neng Song sheng-yu wang Juan Lin Jun-Rong Zhang Yong Ma School of Physics and Electronics Shandong Normal University Jinan 250014 China

The chemisorbed structure for an aromatic molecule on a silicon surface plays an important part in promoting the development of organic semiconductor material science. The carbon K-shell x-ray photoelectron spectroscopy（XPS） and the x-ray absorption near-edge structure（XANES） spectra of the interfacial structure of an s-triazine molecule adsorbed on Si（100） surface have been performed by the first principles, and the landscape of the s-triazine molecule on Si（100） surface has been described in detail. Both the XPS and XANES spectra have shown their dependence on different structures for the pristine s-triazine molecule and its several possible adsorbed configurations. By comparison with the XPS spectra, the XANES spectra display the strongest structural dependency of all of the studied systems and thus could be well applied to identify the chemisorbed s-triazine derivatives. The exploration of spectral components originated from non-equivalent carbons in disparate local environments has also been implemented for both the XPS and XANES spectra of s-triazine adsorbed configurations.

关键词： s-triazine silicon surface x-ray photoelectron spectroscopy (XPS) x-ray absorption near-edge structure (XANES)

The Metabolic Responses of Aspergillus flavus to N-Acetylcysteine,Ascorbate,and H2O2

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Agricultural Sciences in China 2008年第1期7卷 74-81页

作者： HUANG Jia-quan JIANG Hui-fang wang sheng-yu LEI Yong LIAO Bo-shou National Center for Oil Crops Improvement/Key Laboratory of Oil Crops Improvement Ministry of Agriculture~Oil Crops ResearchInstitute Chinese Academy of Agricultural Sciences Wuhan 430062 P.R.China

Aflatoxin, the secondary metabolite of Aspergillus flavus and A. parasiticus, is the most toxic product in nature. In this study, N-acetylcysteine （NAC）, ascorbate, and H2O2 were used to ascertain their effects on fungal metabolic response of A. flavus. The results demonstrated that NAC did not affect fungal growth, but inhibited the aflatoxin Bt production, with the concomitant sporulation reduction. NAC increased the ratio of reduced glutathione （GSH） and oxidized glutathione （GSSG）, but decreased the activity of glutathione reductase （GR）. Ascorbate had similar effect on fungal growth, sporulation, and GR activity, but GSH/GSSG and total glutathione （tGSH, including GSH and GSSG） were significantly increased. H2O2 at high concentration （5 mM） inhibited fungal growth, but the aflatoxin production was increased. At the same time, it reduced GR activity and enhanced tGSH. Though reductive agents had different effects on GSH metabolism, reductive conditions inhibited aflatoxin production and sporulation without any effect on fungal growth. The results in this report confirmed that the relationship between oxidative stress and aflatoxin production is theoretically important in controlling aflatoxin contamination.

关键词： Aspergillus flavus aflatoxin glutathione metabolism