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Chinese Chemical Letters 1995年第5期6卷 403-406页

作者： Xie, HW Liu, sy Wang, LX Shun, YQ Chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R China

The thermal decmpos ition of polyani line(PAn) and poly-o-toluidine (POT)was studied by means of direct pyrolysis mass spectrometry (DPMS) and MS/MS. The results showed that both benzene-diamine and guinone-diimine units were produced,and the intensities of fragments corresponding to quinone-diimine units increased as the oxidation degrees increased The mechanism of thermal decomposition of PAn and POT was given for the first time.

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The transgression record of the Gucheng Lake in 9.6 ka B. P.

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Chinese Science Bulletin 1997年第17期42卷 1459-1461页

作者： Shen, J Wang, SM Liu, sy Zhang, G Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

THE Gucheng Lake is located in Gaochun County, Jiangsu Province, China (31°14′36'—31°19′28'N, 118°51′34'—118°57′56'E). It lies in the southeast monsoon climate area. To study the pateoclimatic and environmental change of the lake area since Late Ice Age and clarify evolution of the southeast monsoon, a core of 20 m (GS1) was drilled at the center of

关键词： Gucheng Lake sedimental core transgression record.

Imperfect Channel State Information of AF and DF Energy Harvesting Cooperative Networks

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China Communications 2016年第10期13卷 11-19页

作者： Hoang-sy NGUYEN Anh-Hoa BUI Dinh-Thuan DO Miroslav VOZNAK Wireless Communications Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang UniversityHo Chi Minh City Vietnam Eastern International University Binh Duong Province Vietnam Faculty of Electrical Engineering and Computer Science Technical University of Ostrava17. Listopadu 15/2172 70833 Ostrava Czech Republic

Wireless information and powered transfer networks(WIPT) has recently been implemented in 5th generation wireless networks. In this paper, we consider half-duplex relaying system in which the energy constrained relay node collects energy via radio frequency(RF) signals from the surrounding resources. Regarding energy harvesting protocol, we propose power time switching-based relaying(PTSR) architecture for both amplify-and-forward(AF) and decode-and-forward(DF). Especially, we reveal the analytical expressions of achievable throughput, ergodic capacity and energy-efficient in case of imperfect channel state information(CSI) for both AF and DF network. Through numerical analysis, we analyse the throughput performance, energy-efficient and ergodic capacity for different parameters, including power splitting ratio and energy harvesting time. Moreover, we also depict the performance comparison between AF and DF network with perfect and imperfect CSI. The results in numerical analysis reveal that the result of AF relaying network is less significant than DF relaying network in the various scenarios.

关键词： amplify-and-forward decode-and-forward energy harvesting throughput channel state information(CSI)

Dioxygen Affinities and Biomimetic Catalytic Performance of Transition-metal Complexes with Crowned Bis-Schiff bases

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Chinese Chemical Letters 2000年第12期11卷 1053-1056页

作者： Lu, XX Li, HB Zeng, W Yang, H Qin, sy Sichuan Univ Dept Chem Chengdu 610064 Peoples R China

The dioxygen affinities and biomimetic catalytic performance of transition-metal complexes with (15-crown-5) salophen and its substituted derivatives Mere examined. The oxygenation constants of Co(II) complexes with crowned bis-Schiff bases were measured and their Mn(III) complexes were employed as models to mimic monooxygenase in catalytic epoxidation of styrene. The highest conversion and selectivity were up to 57.2% and 100% respectively at ambient temperature and pressure. The effects of crown ether ring and substituents R on the dioxygen affinities and catalytic activities were also investigated through comparing with the uncrowned analogues.

关键词： transition-metal complex (15-crown-5) salophen dioxygen affinity catalytic epoxidation monooxygenase-mimicking

Response to Inoculation with Arbuscular Mycorrhizal Fungi of Two Tomato (Solanum lycopersicum L.) Varieties Subjected to Water Stress under Semi-Controlled Conditions

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Agricultural Sciences 2022年第12期13卷 790-819页

作者： Abdou Khadre Sané bassirou Diallo Aboubacry kane Mariama Ngom Maïmouna Cissoko Mame Ourèye sy Laboratoire Campus de Biotechnologies Végétales Département de Biologie Végétale Faculté des Sciences et Techniques Université Cheikh Anta Diop de Dakar Dakar Sénégal Laboratoire Mixte International-Adaptation des Plantes et Microorganismes associés aux Stress Environnementaux (LMI-LAPSE) IRD ISRA UCAD Dakar Sénégal Laboratoire National de Recherches sur les Productions Végétales (LNRPV) Unité de recherche en culture in vitro (URCI) Institut Sénégalais de Recherches Agricoles (ISRA) Dakar Sénégal Laboratoire Commun de Microbiologie (LCM) IRD/ISRA/UCAD Centre de Recherche de Bel Air Dakar Senegal

In arid and semi-arid regions, the growth and development of cultivated plants, especially tomato (Solanum lycopersicum L.), are severely limited by water deficit. Thus, to cope with this constraint, the plant establishes symbiotic relationships with arbuscular mycorrhizal fungi (AMF) in the soil whose extension of the hyphae allows a better and deeper exploration;this notably improves the hydromineral nutrition of the plant. Therefore, the choice of fungal partner becomes crucial for the establishment of a crop in water-deficient soil. In this context, the contribution of AMF to the water stress tolerance of two varieties of tomato plants was assessed under semi-controlled conditions. Parameters, such as the mycorrhizal frequency, intensity of mycorrhization, relative mycorrhizal dependency, growth, and biochemical parameters (carbon, nitrogen, phosphorus, and proline contents) of plants subjected to three levels of water stress (T100, T70, and T30), were evaluated. The highest frequencies and intensities of mycorrhization and relative mycorrhizal dependencies were obtained with plants of the Xewel variety inoculated with Rhizophagus fasciculatus (F: 95.24%, 88.35%, and 13.64%;M: 40.52%, 37.52%, and 11.22%;D: 23.7%, 54.4%, and 78.82%) and in those of the Lady Nema variety inoculated with Claroideoglomus etunicatum (F: 95.12%, 87.01%, and 15.25%;M: 40.66%, 37.99%, and 11.42%;D: 19.27%, 57.01%, and 70.98%), respectively at water regimes of T100, T70 and T30. These same symbiotic couples recorded, at T30, the best survival rates (+ 40%) and the higher aerial (77% and 74%) and root dry weights (80% and 59%). Plants of the Xewel variety inoculated with R. fasciculatus recorded the highest contents of carbon (T70: 30.59% and T30: 21.55%) and phosphorus (T70: 0.18% and T30: 0.17%). Plants of the Lady Nema variety recorded the highest nitrogen contents with 3.51% and 3.20%, respectively at T70 and T30. Plants of the Lady Nema variety, inoculated with C. etunicatum, also re

关键词： Solanum lycopersicum Water Stress Arbuscular Mycorrhizal Fungi Growth Carbon Nitrogen Phosphorus Proline Tolerance

THE NEW DITERPENE ALKALOIDS FROM ACONITUM TRANSSECTUM

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Chinese Chemical Letters 1996年第2期7卷 135-138页

作者： Gao, LM Hao, XJ Zhan, SZ Shen, XW Chen, sy NW NORMAL UNIV LANZHOU 730070PEOPLES R CHINA ACAD SINICA KUNMING INST BOTKUNMING 650204PEOPLES R CHINA

Three new diterpene alkaloids, transconitine A, B and C were isolated from the roots of Aconitum transsectum Diels, and their structures were elucidated by spectral means.

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EXPERIMENTAL INVESTIGATION AND COMPUTER SIMULATION ON dyNAMIC BUCKLING BEHAVIOR OF LIQUID-FILLED CYLINDRICAL SHELLS UNDER AXIAL IMPACT

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Acta Mechanica Solida Sinica 2000年第2期13卷 166-172页

作者： Zhang, sy Lei, JP Zhao, LM Cheng, GQ Lu, GY Taiyuan Univ Technol Inst Appl Mech Taiyuan 030024 Peoples R China

This article reports an experimental investigation on the axial impact buckling of thin metallic cylindrical shells fully filled with water. Low velocity impact tests are carried out by DHR-9401 drop hammer rig. The whole process of dynamic buckling is simulated using LS-dyNA computer code. The consistency between experimental observation and numerical simulation is quite satisfactory. The investigation indicates that quite high internal hydrodynamic pressure occurs inside the shell during the impact process. Under the combined action of the high internal pressure and axial compression plastic buckling occurs easily in the thin-walled shells and buckling modes take on regular and axisymmetric wrinkles.

关键词： liquid-filled cylindrical shell impact buckling experimental investigation computer simulation

Haemorrhage Secondary to Cerebral Aneurysm in a Senegalese Patient with systemic Lupus Erythematosus:A Case Report

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Health 2019年第12期11卷 1625-1630页

作者： baidy sy kane Maimouna Sow Boundia Djiba Awa Cheikh Ndao Mohamed Dieng Souhaibou Ndongo Abdoulaye Pouye Department of Internal Medicine Le Dantec Teaching HospitalCheikh Anta DIOP UniversityDakarSenegal

Introduction: Hemorrhage by ruptured cerebral aneurysm is a rare and severe complication of systemic lupus erythematosus (SLE). We reported a case of this complication. Observation: A 24-year-old woman black Senegalese patient was followed in our department since for a systemic lupus with cutaneous and articular involvement and class III and V Lupus nephritis. She was readmitted for acute headache and early postprandial vomiting. The examination showed a meningeal syndrome, a subacute lupus eruption in the trunk, panniculitis and fever. The cerebral computer tomography showed spontaneous haemorrhage from saccular aneurysm. She was managed by immediate aneurysm clipping and medical treatment including bolus of methylprednisolone and immunosuppressive therapy was maintained. The outcome was favourable, but there was neurological damage such as brachial weakness. Conclusion: Hemorrhage by ruptured cerebral aneurysm is a rare and severe complication of SLE. The risk of damage is also significant. Immediate neurosurgical management and aggressive medical treatment may improve the prognosis.

关键词： systemic Lupus Erythematosus Central Nervous system Lupus Subarachnoid Hemorrhage Africa South of the Sahara

Phase-field lattice Boltzmann model for dendrites growing and moving in melt flow

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npj Computational Materials 2019年第1期5卷 140-149页

作者： LászlóRátkai Tamás Pusztai LászlóGránásy Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Brunel Centre of Advanced Solidification Technology Brunel UniversityUxbridgeMiddlesex UB83PHUK

The phase-field and lattice Boltzmann methods have been combined to simulate the growth of solid particles moving in melt *** handle mobile particles,an overlapping multigrid scheme was developed,in which each individual particle has its own moving grid,with local fields attached to *** this approach we were able to simulate simultaneous binary solidification,solute diffusion,melt flow,solid motion,the effect of gravity,and collision of the *** method has been applied for describing two possible modes of columnar to equiaxed transition in the Al–Ti system.

关键词： solidification moving lattice

synthesis,Characterization and Catalytic Activity of ZnAl Anionic Clay Pillared by α-Na_(6)[GaW_(11)O_(39)Fe(H_(2)O)]·18H_(2)O

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Chemical Research in Chinese Universities 1998年第4期14卷 8-10页

作者： Yu, XW Zhang, sy Huang, RD Zhang, SX Wang, EB NE Normal Univ Dept Chem Changchun 130024 Peoples R China

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｎｉｏｎｉｃｃｌａｙｉｓａｌｓｏｃａｌｅｄｌａｙｅｒｅｄｄｏｕｂｌｅｈｙｄｒｏｘｉｄｅ（ｎｏｔｅｄａｓＬＤＨ），ｉｔｓｕｎｉｑｕｅｂａｓｉｃｃａｔａｌｙｔｉｃｆｕｎｃｔｉｏｎ，ｉｎｔｅ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｎｉｏｎｉｃｃｌａｙｉｓａｌｓｏｃａｌｅｄｌａｙｅｒｅｄｄｏｕｂｌｅｈｙｄｒｏｘｉｄｅ（ｎｏｔｅｄａｓＬＤＨ），ｉｔｓｕｎｉｑｕｅｂａｓｉｃｃａｔａｌｙｔｉｃｆｕｎｃｔｉｏｎ，ｉｎｔｅｒｅｓｔｉｎｇ“ｍｅｍｏｒｙｅｆｅ...

关键词： Anionic clay Heteropolyanion Catalytic activity