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Anchoring of 10-phenylphenothiazine to mesoporous silica materials:A water compatible organic photocatalyst for the degradation of pollutants

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Journal of Materials Science & Technology 2022年第8期103卷 134-143页

作者： daniel González-Muñoz Almudena Gómez-Avilés Carmen b.Molina Jorge bedia Carolina belver Jose Alemán Silvia Cabrera Organic Chemistry Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain Chemical Engineering Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain Institute for Advanced Research in Chemical Sciences(IAdChem) Universidad Autónoma de Madrid28049 MadridSpain Inorganic Chemistry Department Science FacultyUniversidad Autónoma de Madrid28049 MadridSpain

The application of organic photocatalysts towards the oxidation of pollutants in water is hampered by different limitations such as their insolubility in the ***,we report that the grafting of a photoorganocatalyst into mesoporous silica materials is an ideal approach to obtain effective ***,the photocatalyst 10-phenylphenothiazine(PTH)was easily anchored into three different mesoporous silica-based materials(MSN,MSU-2 and SbA-15)with different particle sizes and pore sizes through an amide bond *** materials were characterized using IR analysis,solid-state X-ray diffraction,porosity and microscopy(SEM and TEM)techniques,showing that PTH is immobilized inside the pores of the materials and its optical properties are maintained after the *** homogeneous PTH was inactive in water media,the three photocatalytic materials were active for the degradation of ***-15-AP-PTH exhibited the highest catalytic performance towards the degradation of acetaminophen and diclofenac under solar irradiation,finding in this manner a new strategy for the decontamination of pollutants.

关键词： Organic semiconductors Silica support Solar photocatalysis Water treatment Pharmaceuticals

The effect of wilderness and medical training on injury and altitude preparedness among backcountry hikers in Rocky Mountain National Park

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World Journal of Emergency Medicine 2018年第3期9卷 172-177页

作者： Michael D.T.Yue David W.Spivey daniel b.Gingold Douglas G.Sward University of Maryland School of Medicine BaltimoreMarylandUSA Department of Emergency Medicine University of Maryland School of MedicineBaltimoreMarylandUSA Division of Hyperbaric Medicine Program in TraumaUniversity of Maryland Medical CenterBaltimoreMarylandUSA

bACKGROUND:The purpose of this study was to document the correlation between medical and wilderness training with levels of preparedness for acute mountain sickness(AMS),illness,and injury among backcountry ***:We conducted a cross-sectional,convenience survey in Rocky Mountain National Park in July and August *** study group consisted of 380 hikers who completed a written survey that collected information about demographics,wilderness experience,altitude experience,hiking equipment,communications devices,and trip ***:Factors such as wilderness training(wilderness first aid[WFA],wilderness first responder[WFR],or wilderness emergency medical technician[WEMT]),wilderness experience,and altitude experience all affected hikers’emergency *** with medical training were more prepared to avoid or respond to AMS(62.3%vs.34.3%[Pbe prepared to avoid or respond to AMS(52.3%vs.36.8%[P=0.025])but not significantly more likely to be prepared to manage illness/injury(31.8%vs.22.0%[Pbe prepared to avoid or manage AMS,medical emergencies,and injuries than their non-medically trained *** training increased hikers’preparedness for AMS but did not significantly alter preparedness for illness/injury.

关键词： Hiking wilderness Acute mountain illness Injury Training

A Fully Coupled Thermomechanical Model of Friction Stir Welding(FSW) and Numerical Studies on Process Parameters of Lightweight Aluminum Alloy Joints

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 1-18页

作者： Saad b.Aziz Mohammad W.Dewan daniel J.Huggett Muhammad A.Wahab Ayman M.Okeil T.Warren Liao Department of Mechanical and Industrial Engineering Louisiana State University Department of Civil and Environmental Engineering Louisiana State University

This paper presents a new thermomechanical model of friction stir welding which is capable of simulating the three major steps of friction stir welding （FSW） process, i.e., plunge, dwell, and travel stages. A rate-dependent Johnson- Cook constitutive model is chosen to capture elasto-plastic work deformations during FSW. Two different weld schedules （i.e., plunge rate, rotational speed, and weld speed） are validated by comparing simulated temperature profiles with experimental results. based on this model, the influences of various welding parameters on temperatures and energy generation during the welding process are investigated. Numerical results show that maximum temperature in FSW process increases with the decrease in plunge rate, and the frictional energy increases almost linearly with respect to time for different rotational speeds. Furthermore, low rotational speeds cause inadequate temperature distribution due to low frictional and plastic dissipation energy which eventually results in weld defects. When both the weld speed and rotational speed are increased, the contribution of plastic dissipation energy increases significantly and improved weld quality can be expected.

关键词： Aluminum alloy Friction stir welding Temperature distribution Plastic energy Frictional energy Rate-dependent model Friction modeling

Impact of Friction Stir Welding (FSW) Process Parameters on Thermal Modeling and Heat Generation of Aluminum Alloy Joints

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 869-883页

Friction stir welding （FSW） is a solid-state joining process, where joint properties largely depend on the amount of heat generation during the welding process. The objective of this paper was to develop a numerical thermomechanical model for FSW of aluminum--copper alloy AA2219 and analyze heat generation during the welding process. The thermomechanical model has been developed utilizing ANSYS APDL. The model was verified by comparing simulated temperature profile of three different weld schedules （i.e., different combinations of weld parameters in real weld situations） from simulation with experimental results. Furthermore, the verified model was used to analyze the effect of different weld parameters on heat generation. Among all the weld parameters, the effect of rotational speed on heat generation is the highest.

关键词： Friction stir welding Frictional dissipation energy Temperature distribution Friction modeling Aluminum alloy

Additive friction stir deposition of AZ31b magnesium alloy

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Journal of Magnesium and Alloys 2022年第9期10卷 2404-2420页

作者： Sameehan S.Joshi Shreyash M.Patil Sangram Mazumder Shashank Sharma daniel A.Riley Shelden Dowden Rajarshi banerjee Narendra b.Dahotre Department of Materials Science and Engineering University of North Texas3940 N Elm StDentonTX 76207USA Center for Agile and Adaptive Additive Manufacturing University of North Texas3940 N Elm StDentonTX 76207USA

The current work explored additive friction stir deposition of AZ31b magnesium alloy with the aid of MELD?***31b magnesium bar stock was fed through a hollow friction stir tool rotating at constant velocity of 400 rpm and translating at linear velocity varied from 4.2 to 6.3 mm/s.A single wall consisting of five layers with each layer of 140×40×1 mm^(3)dimensions was deposited under each processing ***,phase,and crystallographic texture evolutions as a function of additive friction stir deposition parameters were studied with the aid of scanning electron microscopy including electron back scatter diffraction and X-ray *** feed material and additively produced samples consisted of theα-Mg *** additively produced samples exhibited a refined grain structure compared to the feed *** feed material appeared to have a weak basal texture,while the additively produced samples experienced a strengthening of this basal *** additively produced samples showed a marginally higher hardness compared to the feed *** current work provided a pathway for solid state additive manufacturing of Mg suitable for structural applications such as automotive components and consumable biomedical implants.

关键词： Additive friction stir deposition Magnesium alloys Additive manufacturing Thermomechanical processing Materials processing Solid state additive manufacturing

Effect of surcharge loading on horseshoe-shaped tunnels excavated in saturated soft rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第6期12卷 1339-1346页

作者： Dianchun Du daniel Dias Ngocanh Do School of Civil Engineering Southeast UniversityNanjingChina School of Automotive and Transportation Engineering Hefei University of TechnologyHefeiChina Antea Group AntonyFrance Department of Underground and Mining Construction Faculty of Civil EngineeringHanoi University of Mining and GeologyHanoiViet Nam

Underground facilities are usually constructed under existing buildings,or buildings are constructed over existing underground *** is then imperative to account for the current overburden loads and future surface loadings in the design of *** addition,tunnels are often constructed beneath the groundwater level,such as cross-river ***,it is also important to consider the water pressure impact on the tunnel lining *** excavated by a conventional tunnelling method are considered in this *** hyperstatic reaction method(HRM)is adopted in this study to investigate the effect of surcharge loading on a horseshoe-shaped tunnel behaviour excavated in saturated soft *** results obtained from the HRM and numerical modelling are in good *** studies were then performed to show the effects of the water pressure,surcharge loading value and its width,and groundwater level on the behaviour of the horseshoe-shaped tunnel lining,in terms of internal forces and *** displays that the bending moment,normal forces and radial displacements are more sensitive to the water pressure,surcharge loading and groundwater level.

关键词： Surcharge loading Horseshoe-shaped tunnel Hyperstatic reaction method(HRM) Saturated soft rocks

Electronic Absorption Spectroscopy of H2X （X=O, Te, Po）： Theoretical Treatment of Spin-Orbit Effects

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Chinese Journal of Chemical Physics 2009年第2期22卷 171-177页

作者： Chérif A. A. Ndoye Chantal daniel Laboratoire de Chimie Quantique Institut de Chimie UMR 7177 CNRS-Université de Strasbourg 4 Rue Blaise Pascal 67000 Strasbourg France

The electronic spectroscopy of H2X （X=O, Te, Po） was investigated by means of spinorbit configuration interaction （EPCISO） and restricted active space state interaction （SORASSI）. The transition energies to the low-lying singlet and triplet states of H2O, in which the SO interaction is zero, compare rather well with the experimental data as well as to other theoretical values. The theoretical electronic absorption spectrum is characterized by three allowed transitions A^1b1 （2px（O）→σ^＊g/3s（O））, b^1A1（σg→σ^＊g/3s（O）） and A^1S2（σg→σ^＊u） calculated at 7.68, 9.94, and 11.72 eV, respectively. The theoretical absorption spectra of H2X （X=Te, Po） are shifted to the red with the A^1b1 （npx（X）→σ^＊g） states calculated at 5.06 eV （H2Te） and 4.40 eV （H2Po） and the A^1b2 （σg→σ^＊u） states calculated at 7.89 eV （H2Te） and 7.77 eV （H2Po）. The largest SO splitting amounts to 0.34 eV and is found for the lowest a^3A1 of H2Po. In H2Te the SO effects are still negligible with a maximum splitting of 0.04 eV for the lowest a^3b2. The two methods lead to comparable results but the EPCISO approach depends strongly on the reference wavefunction.

关键词： Spin-orbit Excited state Group Ⅵ dihydride

Pinch Point Calculations and Its Implications on Robust Distillation Design

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Chinese Journal of Chemical Engineering 2011年第6期19卷 911-925页

作者： daniel A. beneke Seon b. Kim Andreas A. Linninger Laboratory for Product and Process Design Department of Chemical and Bio Engineering University of Illinois at Chicago Chicago IL 60607 USA Centre of Materials and Process Synthesis （COMPS） School of Process and Materials Engineering University of the Witwatersrand Johannesburg South Africa

Rising energy costs and growing environmental awareness motivate a critical revision of the design of distillation units. Systematic design techniques, such as the rectification body, column profile map, and temperature collocation methods, require exact knowledge of all pinch points in a particular system, because these stationary points delineate the possible composition trajectories realizable in separation columns. This paper demonstrates novel methods for rigorously determining all pinch points for the constant relative volatility, ideal and non-ideal systems. Constant relative volatility and ideal solution systems are transformed into one-dimensional polynomial and nonlinear functions, regardless of the number of the components. A deflation method is proposed to locate all zeros in ideal and non-ideal zeotropic problems. For more challenging non-ideal problems, a novel hybrid sequential niche algorithm is used to solve hard azeotropic problems successfully. Finally, the design implications of these pinch point locations are investigated to show how new separation configurations can be devised. Methodically the paper points out the use of rigorous pinch point computations in conjunction with continuous composition profiles for robust distillation design.

关键词： pinch point column profile map phase equilibrium model temperature collocation

Comparison of reduced point charge models of proteins: Molecular Dynamics simulations of Ubiquitin

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Science China Chemistry 2014年第10期57卷 1340-1354页

作者： LEHERTE Laurence VERCAUTEREN daniel P. Unité de Chimie Physique Théorique et Structurale Laboratoire de Physico-Chimie Informatique Namur MEdicine & Drug Innovation Center (NAMEDIC) Department of Chemistry University of Namur Rue de Bruxelles 61 B-5000 Namur Belgium

Reduced point charge models of amino acids are used to model Ubiquitin （PDb： 1UbQ）. They are designed （i） from local ex- tremum positions in charge density （CD） distribution functions built from the Poisson equation applied to smoothed molecular electrostatic potential functions, or （ii） from local maximum positions in promolecular electron density distribution （ED） func- tions. Charge values are fitted versus all-atom Amber99 molecular electrostatic potentials. The program GROMACS is used to generate molecular dynamics trajectories of the protein, under various implementation schemes, solvation, and temperature conditions. Point charges that are not located on atoms are considered as virtual sites with a null mass and radius. The results illustrate that secondary structure is best preserved with the CD-based model at low temperatures and in vacuum. This indi- cates that local potential energy wells are consistent with the all-atom model. However, at room temperature, the structure is best conserved when point charges are forced to be located on atoms, due to a better description of the Coulomb l-4 energy terms. The ED-based model, generated at a lower resolution, led to the largest discrepancies versus the all-atom case. The CD-based model allows the formation of protein-water H-bonds with geometrical properties similar to the all-atom ones. Con- trarily, intra-molecular H-bonds are not well described. Structural, thermodynamical, and dynamical properties of proteins modelled with reduced point charge models are also significantly affected by the choice of the solvent force field.

关键词： molecular electrostatic potential electron density smoothing of molecular fields critical points point charge model protein Ubiquitin