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Novel synthesis of N-substituted-calix[4]azacrown derivatives

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Chinese Chemical Letters 2010年第7期21卷 807-809页

作者： Zhi Qiang Shi Ya Qing Feng shu xian Meng Renai College of Tianjin University Tianjin 301636China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

A novel series of calix[4]azacrown derivatives with the reaction between calix[4]azacrown and the different fluorophore derivatives,which may be useful fluorescent receptors,have been synthesized and structurally characterized by IR,~1H NMR,^（13）C NMR and *** their analysis data,it was found those compounds adopted a cone conformation.

关键词： Calixazacrown Naphthalimide Fluorescent sensors Synthesis Characterization

The X-ray nature of the nucleus in Seyfert 2 galaxy NGC 7590

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Research in Astronomy and Astrophysics 2012年第9期12卷 1247-1254页

作者： Xin-Wen shu Jun-xian Wang Teng LiuI and Wei Zheng CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China Hefei 230026 China xwshu @*** Department of Physics and Astronomy The Johns Hopkins University Baltimore MD 21218USA

We present the results of the Chandra high-resolution observation of the Seyfert 2 galaxy NGC 7590. This object was reported to show no X-ray absorption in the low-spatial resolution ASCA data. The XMM-Newton observations show that the X-ray emission of NGC 7590 is dominated by an off-nuclear ultra-luminous X- ray source (ULX) and extended emissions from the host galaxy, and the nucleus is rather weak, likely hosting a Compton-thick AGN. Our recent Chandra observation of NGC 7590 enables us to effectively remove the X-ray contamination from the ULX and the extended component. The nuclear source remains undetected at the flux level of ～ 4 × 10-15 erg cm-2 s-1. Although not detected, the Chandra data give a 2- 10 keV flux upper limit of ～ 6.1 × 10-15 erg cm-2 s-1 (at a 3σ level), a factor of three less than the XMM-Newton value, strongly supporting the Compton-thick nature of the nucleus. In addition, we detected five off-nuclear X-ray point sources within the galaxy's D25 ellipse, all with 2 - 10 keV luminosity above 2×1038 erg s-1 (assuming the distance of NGC 7590). In particular, the ULX previously identified by ROSAT data is resolved by Chandra into two distinct X-ray sources. Our analysis highlights the importance of high spatial resolution images in discovering and studying ULXs.

关键词： galaxies: active — galaxies: individual (NGC 7590) — galaxies: nuclei — X-rays: galaxies

Surface Modification of Polypropylene by Ethylene Plasma and Its Induced β-Form in Polypropylene

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Chinese Journal of Polymer Science 2015年第5期33卷 669-669,670-673页

作者：马桂秋 Ya-peng Liu shu-xian Wei Jing Sheng School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

This study aims to investigate the chemical structure and morphology of plasmapolymers produced by deposition of ethylene on the surface of polypropylene. The deposition films（sediments） of ethylene plasma on the surface of polypropylene are nonuniform, and the characterization results indicate the existence of hydroxyl groups and aldehyde（or ketone） groups in the sediments. The sediment of ethylene plasma on the polypropylene surface could induce the growth of β-form crystals in the surface layer of polypropylene.

关键词： Plasma polymerization Plasma modification of polypropylene β-Form polypropylene

Syndiospecific Polymerization of Styrene Catalyzed by Half-titanocenes Containing Monodentate Anionic Nitrogen Ligands

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Chinese Journal of Chemistry 2021年第10期39卷 2815-2822页

作者： Dan-Dan Pan Ke-Xin Fan shu Zhang Yi-xian Wu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029 China

Main observation and conclusion Styrene polymerization catalyzed by the half-titanocenes CpTiCl_(2)[1,3-R_(2)(CH_(2)N)_(2)C=N](6b:R=_(2),6-Me_(2)C_(6)H_(3),T_(4):R=_(2),4,6-Me_(3)C_(6)H_(2);T5:R=_(2),6-iPr_(2)C_(6)H_(3))was carried out in the presence of methylaluminoxane(MAO).Compared to the styrene conversion(31%)and syndiospecific index(45%)using reported 6b as precatalyst,T5 bearing ligand with isopropyl substitutes on the N-aryl-rings exhibits much higher styrene conversion(61%)and syndiospecific index(99%),indicating that the catalytic behavior could be improved obviously by the introduction of electronic donating and steric bulky *** N atom in imidazolin-_(2)-iminato ligand was replaced by O atom,affording half-titanocenes CpTiCl_(_(2))[3-C6H5(CH_(2)N)(CH_(2)O)C=N(T1)and CpTiCl_(_(2))[_(2),6-Me_(2)(C6H3O)(NiPr_(2))C=N](T_(2)).Compared to 6b,both higher styrene conversion and syndiospecific index are afforded by using half-titanocene T1 containing_(2)-imino-3-phenyloxazolidine *** the results illustrate that both the chemical structure and the nature of substituents of the ligand have obvious influence on the styrene conversion and syndiospecific index in the polymerization of *** the resulting syndiotactic polystyrenes(sPSs)are highly syndiospecific(rrr>99%).Correspondingly,the sPS prepared using T5/MAO catalytic system exhibits high melting point and narrow molecular weight *** results might show new light on designing more efficient half-titanocenes for styrene polymerization with both high styrene conversion and high syndiospecific selectivity.

关键词： Polymerization Metallocenes N ligands Syndiospecific polymerization Polystyrene

Impact of rock type on the pore structures and physical properties within a tight sandstone reservoir in the Ordos Basin, NW China

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Petroleum Science 2020年第4期17卷 896-911页

作者： xiang-Dong Yin shu Jiang Shi-Jia Chen Peng Wu Wei Gao Ji-xian Gao xian Shi State Key Laboratory of Oil and Gas Reservoir Geology and Exploration Southwest Petroleum UniversityChengdu610500SichuanChina Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education and School of Earth Resources China University of GeosciencesWuhan430074HubeiChina Energy and Geoscience Institute University of UtahSalt Lake CityUT84108USA Unconventional Oil and Gas Branch CNOOC Ltd.Beijing100011China Oil and Gas Technology Research Institute Changqing Qilfield CompanyXi’an City710021ShaanxiChina School of Petroleum Engineering China University of Petroleum(Huadong)Qingdao266000ShandongChina

The pore-throat systems and physical properties of tight sandstone reservoirs are complex,and deposition is thought to be a fundamental control for *** this study,the impacts of the full ranges of rock types(from pebbly coarse sandstone to fine sandstone) on the pore structures and physical properties of the Permian tight sandstone reservoir in the eastern Ordos Basin were investigated comprehensively through a series of experiments including conventional physical testing,thin-section analysis,scanning electron microscopy,nuclear magnetic resonance analysis and high-pressure mercury injection *** results showed that the coarser-grained sandstones tend to have higher feldspar content and lower percentage of cements,leading to strong dissolution,weak cementation and improved porosity and *** medium sandstone has the highest level of quartz and the lowest average content of feldspar,resulting in strong heterogeneity of physical *** those medium sandstone reservoirs with relatively high content of feldspars have better physical ***,the coarser-grained sandstones contain relatively large dissolution pores(nearly 200 μm),whereas the finer-grained sandstones have more intercrystalline pores with a relatively more homogeneous pore *** pebbly coarse sandstone and coarse sandstone reservoirs are favorable targets with best physical properties.

关键词： Pore size distribution Pore types Physical properties Tight sandstone Ordos Basin

3D rock physics template-based probabilistic estimation of tight sandstone reservoir properties

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Petroleum Science 2024年第5期21卷 3090-3101页

作者： Hao-Jie Pan Chao Wei Xin-Fei Yan Xiao-Ming Li Zhi-Fang Yang Zhi-xian Gui shu-xian Liu College of Geophysics and Petroleum Resources Yangtze UniversityWuhan430100HubeiChina Research Institute of Petroleum Exploration and Department PetrochinaBeijing100083China

Quantitative prediction of reservoir properties(e.g., gas saturation, porosity, and shale content) of tight reservoirs is of great significance for resource evaluation and well placements. However, the complex pore structures, poor pore connectivity, and uneven fluid distribution of tight sandstone reservoirs make the correlation between reservoir parameters and elastic properties more complicated and thus pose a major challenge in seismic reservoir characterization. We have developed a partially connected double porosity model to calculate elastic properties by considering the pore structure and connectivity, and to analyze these factors' influences on the elastic behaviors of tight sandstone reservoirs. The modeling results suggest that the bulk modulus is likely to be affected by the pore connectivity coefficient, while the shear modulus is sensitive to the volumetric fraction of stiff pores. By comparing the model predictions with the acoustic measurements of the dry and saturated quartz sandstone samples, the volumetric fraction of stiff pores and the pore connectivity coefficient can be determined. Based on the calibrated model, we have constructed a 3D rock physics template that accounts for the reservoir properties' impacts on the P-wave impedance, S-wave impedance, and density. The template combined with Bayesian inverse theory is used to quantify gas saturation, porosity, clay content, and their corresponding uncertainties from elastic parameters. The application of well-log and seismic data demonstrates that our 3D rock physics template-based probabilistic inversion approach performs well in predicting the spatial distribution of high-quality tight sandstone reservoirs in southwestern China.

关键词： Tight sandstones Pore structure 3D rock physics template Seismic inversion Reservoir property estimation

The front-end electronics design of dose monitors for beam delivery system of Shanghai Advanced Proton Therapy Facility

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Nuclear Science and Techniques 2017年第6期28卷 154-160页

作者： Bin-Qing Zhao Ming-Hua Zhao Ming Liu Chong-xian Yin Hang shu Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A front-end electronics of dose monitor has been developed for measuring irradiation dose to the patient in Shanghai Advanced Proton Therapy *** parallel plate ionization chamber is used for the dose *** the traditional method of recycling capacitor integration and voltage-to-frequency conversion,this dose monitor electronics uses the trans-impedance amplifier and analog-to-digital conversion *** performs satisfactorily,with the integral nonlinearity of less than ±0.04 nA in the range of-400 to 50 nA and the resolution of about±0.6 nA.

关键词： Front-end electronics Dose monitor Proton therapy

Systemic autoimmune abnormalities complicated by cytomegalovirus-induced hemophagocytic lymphohistiocytosis:A case report

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World Journal of Clinical Cases 2020年第20期8卷 4946-4952页

作者： shu-xian Miao Zhi-Qi Wu Hua-Guo Xu Department of Laboratory Medicine The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina

BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a rare but life-threatening disorder,characterized by a hyperimmune *** mortality is high despite progress being made in the diagnosis and treatment of the *** is traditionally divided into primary(familial or genetic)and secondary(reactive)according to the *** HLH(sHLH),more common in adults,is often associated with underlying conditions including severe infections,malignancies,autoimmune diseases,or other *** SUMMARY The case involves a 31-year-old woman,presented with a high persistent fever,rash,and *** met the diagnostic criteria of the HLH-2004 guideline and thus was diagnosed with HLH,with positive anti-nuclear antibody(ANA)and positive cytomegalovirus(CMV)-*** patient responded well to a combination of immunomodulatory,chemotherapy,and supportive *** her PCR evaluation for CMV turned negative,her serum ferritin also dropped *** clinical symptoms improved dramatically,and except for ANA,the abnormal laboratory findings associated with HLH returned to *** previous study has shown that the median overall survival of HLH patients is only 6 mo;however,our patient has been cured and has not presented with any relapse of the disease for 6 *** This case emphasizes that thorough early removal of the CMV infection is significant for the prognosis of this HLH patient.

关键词： Hemophagocytic lymphohistiocytosis Autoimmune abnormalities Cytomegalovirus Anti-nuclear antibody Serum ferritin Case report

Effects of Acetylsalicylic Acid and Calcium Chloride on Photosynthetic Apparatus and Reactive Oxygen-Scavenging Enzymes in Chrysanthemum Under Low Temperature Stress with Low Light

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Agricultural Sciences in China 2010年第12期9卷 1777-1786页

作者： FENG Zhen LIANG Fang ZHENG Cheng-shu shu Huai-rui SUN xian-zhi Yoo Yong-kweon College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Shandong Agricultural University Tai＇an 271018P.R.China National Apple Engineering Technique Center Tai＇an 271018 P.R.China College of Natural Sciences Mokpo Nationeal University Moo an Junramamdo 534-729 P.R.Korea

The effects of acetylsalicylic acid （ASA）, CaCl2, and ASA ＋ CaCl2 on the photosynthetic apparatus and antioxidant enzyme activities were investigated in chrysanthemum Jinba （a cut flower cultivar） under low temperature stress with low light （TL stress）（16/12℃, day/night, PFD 100 μmol m^-2 s-1）. The results showed that under TL stress, the net photosynthesis rate （Pn）, carboxylation efficiency （CE）, apparent quantum yield （AQY）, maximal photochemical efficiency （Fv/Fm） of PSII, quantum yield of PSII electron transport （ФPSII）, and photochemical quenching （qP） of the chrysanthemum leaves in all treatments were significantly decreased, but the decreases were alleviated by ASA, CaCl2, and ASA ＋ CaCl2 treatments compared with the controls. The alleviating effect of ASA ＋ CaCI2 was better than either ASA or CaCl2 single treatment. Moreover, the ASA ＋ CaCl2 treatment highly improved the chlorophyll content, relatively improved the number and size of chloroplast and starch grain in the leaves of chrysanthemum plants compared with ASA and CaCl2 treatments. It was indicated that ASA and/or CaCI2 could regulate the photosynthetic functions in the leaves of chrysanthemum plants to enhance the resistance against TL stress. On the other hand, reduction in relative conductance rate implied that ASA and/ or CaCl2 could protect from membrane injury in leaves of chrysanthemum plants. The activities of SOD, POD, and CAT in the treated leaves of chrysanthemum were increased as compared with the controls. It was suggested that ASA and/or CaCl2 had positive regulation effects on the defence enzyme activities in chrysanthemum leaves which could protect the photosynthetic apparatus to a certain degree under the TL stress. In brief, the treatment of ASA together with CaCl2 was better for chrysanthemum plants to adapt TL stress than single ASA or CaCl2 treatments.

关键词： acetylsalicylic acid Ca^2+ chrysanthemum low temperature low light photosynthetic apparatus antioxidantenzyme