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Chinese Chemical Letters 2015年第5期26卷 575-579页

作者： farid moeinpour amir Khojastehnezhad Department of Chemistry Bandar Abbas BranchIslamic Azad University Young Researchers and Elite Club Mashhad BranchIslamic Azad University

Cesium carbonate supported on hydroxyapatite coated ***2O4 magnetic nanoparticles （***2O4@Hap-Cs2CO3） was found to be magnetically separable, highly efficient, green and recyclable heterogeneous catalyst. The synthesized nanocatalyst has been characterized with several methods （FT-IR, SEm, TEm, XRD and XRF） and these analyzes confirmed which the cesium carbonate is well supported to catalyst surface. After full characterization, its catalytic activity was investigated in the synthesis of pyranopyrazole derivatives and the reactions were carried out at room temperature in 50：50 water/ethanol with excellent yields （88-95%）. more importantly, the ***204@Hap-Cs2CO3 was easily separated from the reaction mixture by external magnetic field and efficiently reused at least six runs without any loss of its catalytic activity. Thus, the developed nanomagnetic base catalyst is potentially useful for the green and economic production of organic compounds.

关键词： Cesium carbonate Catalysis Pyranopyrazoles magnetic nanoparticles Hydroxyapatite

monopile responses to monotonic and cyclic loading in undrained sand using 3D FE with SANISAND-mSu

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Water Science and Engineering 2022年第1期15卷 69-77页

作者： Hao-yuan Liu amir m.Kaynia Norwegian Geotechnical Institute Oslo 0806Norway Norwegian University of Science and Technology Trondheim 7491Norway Norconsult Sandvika 1338Norway

monopile response under undrained conditions in sand is gaining increasing interests owing to the recent development of offshore wind farms in seismic *** pressure evolution in liquefiable soil can significantly reduce the strength and stiffness of the soil which in turn affects the structural dynamic *** numerical models have been developed in the last two decades to enhance understanding of the mechanism of monopile-soil interaction with the existence of pore water *** this study,the effects of geometry and static vertical load on monopile lateral response were studied using three-dimensional finite element methods that consider the existence of lateral cyclic load-induced pore water *** achieve reliable simulation results of pore pressure development and pile displacement accumulation during cyclic loading,the simple anisotropic sand model with memory surface for undrained cyclic behavior of sand was *** piles with the same diameter,a accumulated pile head displacement during lateral cyclic loading decreased linearly with increasing pile embedded length but increased with increasing *** vertical load had minor effects on pile cyclic lateral *** distributions of mean effective stress and pore water pressure in the soil domain were *** pile reaction curve(cyclic soil reaction against pile defection)of the monopile was *** numerical results aim to provide reference for optimized engineering design procedures.

关键词： Offshore monopile Pore pressure Cyclic loading Soil-structure interaction Sand

modelling and applications of dissolution of rocks in geoengineering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第1期24卷 20-36页

作者： farid LAOUAFA Jianwei GUO michel QUINTARD National Institute for Industrial Environment and Risks(INERIS) Verneuil en Halatte60550France School of mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China Universitéde Toulouse INPTUPSIMFT(Institut de Mécanique des Fluides de Toulouse)Allée Camille SoulaToulouseF-31400France CNRS IMFTToulouseF-31400France

The subsoil contains many evaporites such as limestone,gypsum,and *** rocks are very sensitive to *** deposit of evaporites raises questions because of their dissolution with time and the mechanical-geotechnical impact on the neighboring *** on the configuration of the site and the location of the rocks,the dissolution can lead to surface subsidence and,for instance,the formation of sinkholes and *** this study,we present an approach that describes the dissolution process and its coupling with geotechnical *** the first part we set the physico-mathematical framework,the hypothesis,and the limitations in which the dissolution process is *** physical interface between the fluid and the rock(porous)is represented by a diffuse interface of finite *** briefly describe,in the framework of porous media,the steps needed to upscale the microscopic-scale(pore-scale)model to the macroscopic scale(Darcy scale).Although the constructed method has a large range of application,we will restrict it to saline and gypsum *** second part is mainly devoted to the geotechnical consequences of the dissolution of gypsum *** then analyze the effect of dissolution in the vicinity of a soil dam or slope and the partial dissolution of a gypsum pillar by a thin layer of *** theoretical examples show the relevance and the potential of the approach in the general framework of geoengineering problems.

关键词： Dissolution modelling Scaling Evaporite Deformation Plasticity

PPA-SiO_2 catalyzed efficient synthesis of polyhydroquinoline derivatives through Hantzsch multicomponent condensation under solvent-free conditions

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Chinese Chemical Letters 2011年第7期22卷 807-810页

作者： amir Khojastehnezhad farid moeinpour Abolghasem Davoodnia Department of Chemistry Faculty of SciencesIslamic Azad UniversityMashhad BranchMashhad 91735-413Iran Department of Chemistry Faculty of SciencesIslamic Azad UniversityBandar Abbas BranchIran

Silica gel-supported polyphosphoric acid （PPA-SiO2） was found to be an efficient catalyst for the one-pot four-component Hantzsch condensation reaction of aryl aldehydes, dimedone, ethyl acetoacetate and ammonium acetate to afford the corresponding polyhydroquinoline derivatives in high yields. The main advantages of the present approach are short reaction times, clean reaction profiles, simple experimental and workup procedures.

关键词： multicomponent reaction One-pot synthesis Solvent-free Polyhydroquinoline derivatives Silica-supported polyphosphoric acid (PPA-SiO2)

An excimer ‘ON–OFF’ switch based on telomeric G-quadruplex and rGO for trace thrombin detection

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Chinese Chemical Letters 2022年第9期33卷 4243-4247页

作者： Long Zhao farid Ahmed Hai Xiong Institute for Advanced Study Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

In the recent decade,GO has emerged as an amazing 2D nanomaterial for developing DNA-based biosensors due to its fluorescence quenching properties,whereas similar research based on rGO was reported ***,a novel multi-pyrene functionalized G-rich DNA probe based on the screened rGO showed much higher fluorescence quenching efficiency and excimer emission than that of universal *** from the universal thrombin detection of the G4-forming aptamer-TBA(GGTTGGTGTGGTTGG),the original telomeric sequence is used in this *** excimer emission“ON-OFF”switch amplified the response of thrombin detection is as low as 50 ***,for four pyrene moieties that are sited in a crowded steric circumstance,the melting temperature(T_(m))values and molecular dynamics simulations showed a positive effect on duplex G-quadruplex or _(G)DNA·_(c)DNA stability,without disturbing its helix structure.

关键词： G-quadruplexr GOmulti-pyrene excimer Biosensor Thrombin detection

A review of the mechanical integrity and electrochemical performance of flexible lithium-ion batteries

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Nano Research 2023年第12期16卷 12962-12982页

作者： Ahmad Shokrieh amir Hossein mirzaei Lijuan mao mahmood m.Shokrieh Zhixiang Wei CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China Composites Research Laboratory Center of Excellence in Experimental Solid Mechanics and DynamicsSchool of Mechanical EngineeringIran University of Science and TechnologyTehran 16846-13114Iran University of Chinese Academy of Sciences Beijing 100049China

In the past two decades,various research works have been conducted in the field of flexible electronic devices(FEDs).Researchers have focused their efforts on solving the existing challenges in the electronic,electrochemical,and mechanical behaviors of *** importance of flexible lithium-ion batteries(FLIBs)in the area of FEDs is evident;however,less attention has been paid to the mechanical behavior of FLIBs in comparison with the material and electrochemical *** present paper reviewed the research works in the FLIBs,focusing on their mechanical integrity and electrochemical ***,an introduction to FLIBs was presented,and the previous review papers published in this field were briefly ***,a detailed review of the available electrochemical and mechanical research works on FLIBs was ***,the mechanical testing methods(tensile,compressive,indentation,fatigue,and adhesion)for the characterization of FLIBs’components,the research works on the simulation and modeling of the mechanical behavior of FLIBs,and a summary of the present situation and the future trend of research in this field were reviewed and presented.

关键词： flexible devices electrochemical performance mechanical integrity testing methods simulation and modeling.

An Improved Hybrid Indoor Positioning Algorithm via QPSO and mLP Signal Weighting

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Computers, materials & Continua 2023年第1期74卷 379-397页

作者： Edgar Scavino mohd amiruddin Abd Rahman Zahid farid Department of Physics Faculty of ScienceUniversiti Putra MalaysiaUPM Serdang43400Malaysia Department of Electrical Engineering Abasyn UniversityKhyber-PakhtunkhwaPakistan

Accurate location or positioning of people and self-driven devices in large indoor environments has become an important necessity The application of increasingly automated self-operating moving transportation units,in large indoor spaces demands a precise knowledge of their *** like WiFi and Bluetooth,despite their low-cost and availability,are sensitive to signal noise and fading *** these reasons,a hybrid approach,which uses two different signal sources,has proven to be more resilient and accurate for the positioning determination in indoor ***,this paper proposes an improved hybrid technique to implement a fingerprinting based indoor positioning,using Received Signal Strength information from available Wireless Local Area Network access points,together with the Wireless Sensor Networks *** signals were recorded on a regular grid of anchor points,covering the research *** optimization was performed by relative signal weighting,to minimize the average positioning error over the research *** optimization process was conducted using a standard Quantum Particle Swarm Optimization,while the position error estimate for all given sets of weighted signals was performed using amultilayer Perceptron(mLP)neural *** to our previous research works,the mLP architecture was improved to three hidden layers and its learning parameters were finely *** experimental results led to the 20%reduction of the positioning error when a suitable set of signal weights was calculated in the optimization *** final achieved value of 0.725 m of the location incertitude shows a sensible improvement compared to our previous results.

关键词： QPSO indoor localization fingerprinting neural networks WiFi WSN

Organizational Changes Needed in Disasters and Public Health Emergencies:A Qualitative Study among managers at a major Hospital

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International Journal of Disaster Risk Science 2022年第4期13卷 481-494页

作者： Ingela Wennman Catharina Jacobson Eric Carlström Anders Hyltander amir Khorram‑manesh Institute of Health and Care Sciences Sahlgrenska AcademyGothenburg University41346GothenburgSweden Preparedness Unit Sahlgrenska University Hospital41305 GothenburgSweden Institute of Clinical Sciences Department of SurgerySahlgrenska AcademyGothenburg University41345GothenburgSweden

most hospitals have a contingency plan,based on all-risks and all-hazards assessment ***,emerging threats and risks often necessitate a flexible approach to emergency management at several levels of a disaster response system,for example,in ***,and possibly other countries,has limited possibilities of surge capacity in the management of large-scale disasters and emergencies,which necessitates a local/national partnership and a flexible local disaster and contingency *** study evaluates the opinions of a selected managerial group,both at operative and strategic levels,regarding possible changes in a major hospital's contingency plan during the ongoing COVID-19 *** interviews were conducted to explore the elements of surge capacity and an operational tool,consisting of command and control,safety,communication,assessment,triage,treatment,and *** results show a need to create feasible management methods that can be evaluated,establish clear leadership,put preparedness as a constant point on the highest managerial agenda,improve external monitoring,and create a regional coordinating ***,the results emphasize the significant role played by the incident command system and qualified leadership to facilitate competent and crucial medical decision making,as well as to provide reliable communication,collaboration,and coordination in a multi-agency response system during dynamic and unexpected *** steps enable a constant connection between reactive contingency plans and the proactivity in continuous risk assessment and enhance the flexibility of the contingency plans.

关键词： Disaster risks Organizational changes Public health emergencies Sweden

Rational design of hydrogels for immunomodulation

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Regenerative Biomaterials 2022年第1期9卷 979-1000页

作者： Wenhuan Bu Yuanhao Wu amir m.Ghaemmaghami Hongchen Sun Alvaro mata Liaoning Provincial Key Laboratory of Oral Diseases School of StomatologyChina Medical UniversityNo.117Nanjing North StreetHeping DistrictShenyang 110001China Department of Dental materials School of StomatologyChina Medical UniversityNo.117Nanjing North StreetHeping DistrictShenyang 110001China Department of Center Laboratory School of StomatologyChina Medical UniversityNo.117Nanjing North StreetHeping DistrictShenyang 110001China School of Pharmacy University of NottinghamUniversity ParkNottingham NG72RDUK Biodiscovery Institute University of NottinghamUniversity ParkNottingham NG72RDUK Division of Immunology School of Life SciencesUniversity of NottinghamUniversity ParkNottingham NG72RDUK Terasaki Institute for Biomedical Innovation 1018 Westwood BlvdLos AngelesCA 90024USA Department of Chemical and Environmental Engineering University of NottinghamUniversity ParkNottingham NG72RDUK

The immune system protects organisms against endogenous and exogenous harm and plays a key role in tissue development,repair and *** immunomodulatory biologics exhibit limitations including degradation by enzymes,short half-life and lack of targeting *** or binding these biologics within biomaterials is an effective way to address these *** are promising immunomodulatory materials because of their prominent biocompatibility,tuneability and ***,to take advantage of these opportunities and optimize material performance,it is important to more specifically elucidate,and leverage on,how hydrogels affect and control the immune ***,we summarize how key physical and chemical properties of hydrogels affect the immune *** first provide an overview of underlying steps of the host immune response upon exposure to ***,we discuss recent advances in immunomodulatory strategies where hydrogels play a key role through(i)physical properties including dimensionality,stiffness,porosity and topography;(ii)chemical properties including wettability,electric property and molecular presentation;and(iii)the delivery of bioactive molecules via chemical or physical ***,this review aims to build a conceptual and practical toolkit for the design of immune-instructive hydrogels capable of modulating the host immune response.

关键词： hydrogels immunomodulation physical properties chemical properties

Effect of indaziflam on microbial activity and nitrogen cycling processes in an orchard soil

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Pedosphere 2022年第6期32卷 803-811页

作者： amir m.GONZÁLEZ-DELGADO Pierre-AndréJACINTHE manoj K.SHUKLA Department of Plant and Environmental Sciences New Mexico State UniversityLas Cruces NM 88003(USA) Department of Earth Sciences Indiana University Purdue UniversityIndianapolis IN 46202(USA)

Indaziflam is a preemergent herbicide widely used for the control of weeds in pecan(Carya illinoinensis)orchards in the southwestern region of the United *** the paucity of data regarding the effect of indaziflam on the biochemical properties of soils supporting pecan production,this study was conducted to evaluate the effects of different application rates of indaziflam on soil microbial activity,diversity,and biochemical processes related to nitrogen(N)*** two consecutive growing seasons(2015 and 2016),soil samples were obtained from experimental mesocosms consisting of soil-filled pots where pecan saplings were grown and treated with indaziflam applied at two different rates(25 and 50 g active ingredient(ai)ha^(-1),with the higher rate being slightly lower than the recommended field application rate of 73.1 g ai ha^(-1)).Soil samples were collected approximately one week before and one week after herbicide application for determination of soil microbial biomass and diversity,N mineralization,andβ-glucosaminidase *** samples collected from the control mesocosms without herbicide application were treated in the laboratory with two rates of indaziflam(75 and 150 g ai ha^(-1))to determine the immediate effect on microbial *** significant effect of herbicide treatment on soil respiration and microbial biomass was *** results showed a slight to moderate decrease in microbial diversity(7%in 2015 and 44%in 2016).However,decreasedβ-glucosaminidase activity with herbicide treatment was observed in soils from the mesocosms(33%)and soils treated with indaziflam in the laboratory(45%).The mineral N pool was generally dominated by ammonium after indaziflam application,which was consistent with the drastic decrease(75%)in nitrification activity measured in the laboratory *** results of this study indicate that indaziflam,even when applied at higher than recommended rates,has limited effects on soil microbial activity,but

关键词： Carya illinoinensis β-glucosaminidase activity mesocosm experiment microbial biomass microbial diversity mineral nitrogen speciation nitrification