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Arsenic and sulfur nanoparticle synthesis mimicking environmental conditions of submarine shallow-water hydrothermal vents

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Journal of Environmental Sciences 2022年第1期34卷 301-312页

作者： Vicente Durán-Toro Kurosch Rezwan Solveig I.Bühring Michael Maas MARUM–Center for Marine Environmental Sciences University of BremenBremen 28359Germany Advanced Ceramics University of BremenBremen 28359Germany MAPEX-Center for Materials and Processes University of BremenBremen 28359Germany

Arsenic and sulfur mineralization is a natural phenomenon occurring in hydrothermal systems where parameters like temperature and organic matter(OM)can influence the mobilization of the toxic metalloid in marine *** the present study we analyze the influence of temperature and OM(particularly sulfur-containing additives)on As and S precipitation based on the recent discovery of As-rich nanoparticles in the hydrothermal system near the coast of the Greek island *** this end,we experimentally recreate the formation of amorphous colloidal particles rich in As and S via acidification(pH 3–4)of aqueous precursors at various *** higher temperatures,we observe the formation of monodisperse particles within the first 24 h of the experiment,generating colloidal particles with diameters close to 160 *** S:As ratio and particle size of the synthetized particles closely correlates with values for As_(x)S_(y)particles detected in the hydrothermal system off ***,organic sulfur containing additives(cysteine and glutathione,GSH)are a key factor in the process of nucleation and growth of amorphous colloidal As_(x)S_(y)particles and,together with the temperature gradient present in shallow hydrothermal vents,dictate the stabilization of As-bearing nanomaterials in the *** on these findings,we present a simple model that summarizes our new insights into the formation and mobility of colloidal As in aquatic *** this context,amorphous As_(x)S_(y)particles can present harmful effects to micro-and macro-biota not foreseen in bulk As material.

关键词： Biomineralization Milos Hydrothermal vent Arsenic Sulfur Nanoparticles Ecotoxicology

SYNTHESIS　OF　TETRAMETHYL　SALVIANOLIC　ACID　F　AND　TRIMETHYL　PRZEWALSKINIC　ACID　A

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Chinese Chemical Letters 1996年第5期7卷 427-430页

作者： Al, cb Li, LN CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Abstract: Salvianolic acid F (1a) and przewalskinic add A(2a) are phenolic acids isolated from the traditional and herbal Chinese medicines Salvia miltiorrhiza (1) and S. przewalskii (2). The chemical structures of these two compounds represent the main carbon skeletons of the biologically active depsides salvianolicacid A and B isolated from S. miltionhiza (3.4). The present paper reports the synthesis of the methyl ether protected phenolic acids. tetramethyl salvianolic acid F(1b) and trimethyl prsewalskinic acid A(2b).

关键词： ACID TRIMETHYL TETRAMETHYL PRZEWALSKINIC SALVIANOLIC SYNTHESIS AND OF

Investigation on the computation of atomic multipole moments with the modified cumulative potential-derived semiempiricalmethod

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Chinese Journal of Chemistry 1997年第6期15卷 481-491页

作者： Xu, LJ Zhu, cb Yan, JM Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The suitability of calculating atomic multipole moments from AM1 wave functions by cumulative potential-derived method has been investigated. It is shown that this method has a faster convergence of the fitting process and gives a better description of the charge distribution than the original PD method. Atomic charges obtained in this way are of comparable quality with 6-31G* data and the calculated dipole moments are closer to the experimental data than the values computed directly from the AM1 charges. The results demonstrate that the atomic multipole moments higher than monopole moment can be used to supplement the atomic charge to obtain a more accurate description of charge distribution. For the sake of comparison, both the Williams fitting potential surface and the Connolly one are used in the calculation.

关键词： atomic charge atomic multipole moment cumulative fitting AM1

Delamination Testing of AlSi10Mg Sandwich Structures with Pyramidal Lattice Truss Core made by Laser Powder Bed Fusion

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 51-62页

作者： M.Nuño J.Bühring M.N.Rao K.-U.Schröder Institute of Structural Mechanics and Lightweight Design RWTH Aachen UniversityWüllnerstraβe 752072 AachenGermany

Sandwich structures possess a high bending stiffness compared to monolithic structures with a similar *** makes them very suitable for lightweight applications,where high stiffness to weight ratios are *** common manufacturing methods of sandwich structures involve adhesive bonding of the core material with the ***,adhesive bonding is prone to delamination,a failure mode that is often difficult to *** paper presents the results of delamination testing of fully additive manufactured(AM)AlSi10Mg sandwich structures with pyramidal lattice truss core using Laser Powder Bed Fusion(LPBF).The faces and struts are 0.5 mm thick,while the core is 2 mm *** inclination of the struts is 45°.To characterise the bonding strength,climbing drum peel tests and out-of-plane tensile tests are *** formulas are derived to predict the expected failure loads and *** analytics and tests are supported by finite element(FE)*** the analytic approach,design guidelines to avoid delamination in AM sandwich structures are *** study presents a critical face sheet thickness to strut diameter ratio for which the structure can *** ratio is mainly influenced by the inclination of the *** peel tests resulted in face yielding,which can also be inferred from the analytics and *** out-of-plane tensile tests didn’t damage the structure.

关键词： Additive Manufacturing Sandwich Structures Pyramidal Lattice Core

INVESTIGATION　ON　THE　INTERACTION　OF　THE　HALOGEN　ATOMS　WITH　THE　C_（60）　CAGE　IN　THE　HALOGEN－ENCLOSED　COMPLEXES　（HALOGEN＠C_（60））

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Chinese Chemical Letters 1995年第10期6卷 867-870页

作者： Zhu, cb Yan, JM Acad Sinica Inst Chem Beijing 100080 Peoples R China

The interaction between C60 cage and the centerhalogen atoms in endoheoral complexes(HalogenC60)(Halogen=Hal=F,ClBr1),including electro-static interaction,dispersive interection and repulsive interaction,have been calculated by molecular molecular mechanics method combined with the results obtained by quantum-chemical EHMO/ASED method The computational results show that the total interaction is attraction which reduces the endohedral comples system except for,and the electro-static interaction plays a decisive role in the three forms of interactions,reaching up more than 90%. For the endohedral complex the resultant non-bonded interaction is *** is a similar variation trend for the total energy variation of system and the total interaction energy of which the order is (F@C_(60))<(cl@C(60))<(I@C(60)).

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Annealing Effect on Mechanical Properties of Ti_(51)Ni_(13)Pd_(36)High Temperature Memory Alloy

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Journal of Materials Science & Technology 2000年第5期16卷 531-533页

作者： Xu, HB Hu, SQ Jiang, cb Gong, SK Beijing Univ Aeronaut & Astronaut Dept Mat Sci & Engn Beijing 100083 Peoples R China

The high temperature shape memory alloy Ti51Ni13Pd36 was subjected to a cold working and annealing treatment to improve its mechanical properties and the shape memory effect. It was found that recovery of the cold worked alloys started at near 673 K and the recrystallization temperature was at about 748 K. The grain size decreased with the increase of annealing temperature below 923 K and then increased when above 923 K. The smallest average grain size of about 3.5μm, which is approximately 10 times smaller than the hot rolled one, permitted the best combination of the mechanical properties in the alloy annealed at 923 K for 1h. The cold rolling raised the peak temperature of reverse transformation. This temperature dropped very sharply when the specimen was annealed at temperatures higher than 673 K.

关键词： Alloys

Y-Ba-Cu-O mixed oxides for production of diphenols in liquid-solid phase

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Chinese Journal of Chemistry 1996年第6期14卷 516-524页

作者： Liu, cb Zhao, Z Yang, XG Ye, XK Wu, Y CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022JILINPEOPLES R CHINA

Superconductor mixed oxides were often used as catalysts at higher temperature in gas phase oxidations, and considered not suitable for lower temperature reactions in the liquid-solid phase; here the catalysis of YBa2Cu3O7+/-x and Y2BaCuO5+/-x in the phenol hydroxylation at lower temperature with H2O2 as oxygen donor was studied, and found that the superconductor YBa2Cu3O7+/-x, has no catalytic activity for phenol hydroxylation, but Y2BaCuO5+/-x does, even has better catalytic activity and stability than most previously reported ones. With the studies of catalysis of other simple metal oxides and perovskite-like mixed oxides, a radical substitution mechanism is proposed and the experimental facts are explained clearly, and draw a conclusion that the perovskite-like mixed oxides with (AO)(ABO(3)) and (AO)2(ABO(3)) structure have better catalytic activity than the simple perovskite oxides with (ABO(3))(3) structure alone, and (AO) structure unit is the key for the mixed oxides to have the phenol hydroxylation activity. No pollution of this process is very important for its further industrial application.

关键词： superconductor mixed oxides phenol hydroxylation radical substitution

Concealed Integrity Monitoring for Wireless Sensor Networks

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Wireless Sensor Network 2011年第1期3卷 10-17页

作者： Bjorn Stelte Thomas Bühring Institut für Technische Informatik Universitat der Bundeswehr MünchenNeubibergGermany

Nowadays, sensor networks are widely installed around the world. Typical sensors provide data for healthcare, energy management, environmental monitoring, etc. In the future sensors will become a part of critical infrastructures. In such a scenario the network operator has to monitor the integrity of the network devices, otherwise the trustworthiness of the whole system is questionable. The problem is that every integrity protocol needs a secure channel between the devices. Therefore, we will introduce a covert channel for hidden transportation of integrity monitoring messages. The covert channel enables us to hide integrity check messages embedded into regular traffic without giving potential attackers a hint on the used integrity protocol.

关键词： Covert Channel Integrity Monitoring Wireless Sensor Network

Identification of CD13,CD107a,and CD164 as novel basophil-activation markers and dissection of two response patterns in time kinetics of IgE-de-pendent upregulation

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Cell Research 2005年第5期15卷 325-335页

作者： Florian HENNERSDORF,Stefan FLORIAN,Andreas JAKOB,Katharina BAUMGRTNER,Karoline SONNECK,Alfred NORDHEIM,Tilo BIEDERMANN,Peter VALENT,Hans-Jrg Bühring University Clinic of Tübingen Department of Internal Medicine II Division of Hematology and Immunology Tübingen Germany Medical University Clinic of Vienna Department of Internal Medicine I Division of Hematology and Hemostaseology Vienna Austria University of Tübingen Proteome Center Tübingen Germany University Clinic of Tübingen Department of Internal Medicine II Division of Hematology and Immunology Tübingen Germany Medical University Clinic of Vienna Department of Internal Medicine I Division of Hematology and Hemostaseology Vienna Austria University of Tübingen Proteome Center Tübingen Germany University Clinic of Tübingen Department of Dermatology Tübingen Germany Medical University Clinic of Vienna Department of Internal Medicine I Division of Hematology and Hemostaseology Vienna Austria University Clinic of Tübingen Department of Internal Medicine II Division of Hematology and Immunology Tübingen Germany

Using two-colour flow cytometry >200 antibodies submitted to the 8th International Workshop of Human Leukocyte Differentiation Antigens (HLDA8) have been analyzed for their reactivity with resting and activated CD203c+ basophils. Four antibodies either non-reactive or weakly reactive with resting basophils exhibited an increased reactivity with basophils activated by anti-IgE-mediated cross-linking of the high affinity IgE receptor (FcεRI). These include antibod- ies against CD164 (WS-80160, clone N6B6 and WS-80162, clone 67D2), as well as two reagents with previously unknown specificities that were identified as CD13 (WS-80274, clone A8) and CD107a (WS-80280, clone E63-880). The activation patterns followed either the “CD203c-like” or “CD63-like” activation profile. The CD203c profile is characterized by a rapid and significant upregulation (of CD13, CD164, and CD203c), reaching maximum levels after 5- 15 min of stimulation. The phosphoinositide-3-kinase (PI3K)-specific inhibitor wortmannin inhibited the upregulation of these markers whereas 12-O-tetradecanoyl-phorbol-13-acetate (TPA) induced a rapid and FcεRI-independent upregulation within 1-2 min. In the CD63 profile, maximum upregulation (of CD63 and CD107a) was detected only after 20-40 min, and upregulation by TPA reached maximum levels after 60 min. In summary, our data identify CD13, CD107a, and CD164 as novel basophil-activation antigens. Based on time kinetics of upregulation, we hypothesize that molecules of the “CD203c group” and the “CD63 group” are linked to two different mechanisms of basophil activation.

关键词： CD203c CD164 CD63 CD107a basophil activation basophil marker.