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Nano-Micro Letters 2017年第2期9卷 58-67页

作者： Prasenjit Kar Tuhin Kumar Maji Ramesh Nandi Peter Lemmens samir Kumar Pal Department of Chemical Biological and Macromolecular Sciences S.N.Bose National Centre for Basic SciencesBlock JDSector ⅢSaltLakeKolkata 700106India Institute for Condensed Matter Physics TU BraunschweigMendelssohnstraße 338106 BrunswickGermany Laboratory for Emerging Nanometrology TU BraunschweigBrunswickGermany

Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and high-resolution TEM(HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi_2O_2CO_3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue(MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi_2O_2CO_3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs.

关键词： Bi nanoparticles Bi–Bi2O2CO3 nanosheets Heterojunction Hydrothermal method Charge separation Visible light photocatalytic activity

Development of a Smart Technique for Mobile Web Services Discovery

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Computers, Materials & Continua 2021年第11期69卷 1483-1501页

作者： Mohamed Eb-Saad Yunyoung Nam Hazem M.El-bakry samir Abdelrazek Department of Information Systems Faculty of Computers and InformationMansoura UniversityMansoura35516Egypt Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

Web service(WS)presents a good solution to the interoperability of different types of systems that aims to reduce the overhead of high processing in a resource-limited *** the increasing demand for mobile WS(MWS),the WS discovery process has become a significant challenging point in the WS lifecycle that aims to identify the relevant MWSs that best match the service *** discovery process is a resource-consuming task that cannot be performed efficiently in a mobile computing environment due to the limitations of mobile ***,a cloud computing can provide rich computing resources for mobile environments given its unlimited and easily scalable *** paper proposes a semantic WS discovery and invocation framework in mobile environments based on cloud and a relationship-aware matchmaking *** discovery algorithm enriches MWS and user requests semantically with the functional and non-functional properties of Ontology Web Language for Services,such as Quality of Web Service,device context,and user *** WS repository is filtered based on logical reasoning and a parameter-based matching algorithm to minimize the matching space and improve runtime *** cosine similarity between the user request and services repository is then assessed to generate the most relevant *** relationships among concepts in the ontology are considered to improve the recall and precision *** the WS discovery process,users can invoke and test these services in a mobile environment through a dynamic user *** interface of the invocation process is changed according to the WS description *** application prototype is also developed to evaluate the framework based on a Cordova cross-mobile development framework.

关键词： Cloud web service web service discovery semantic matching mobile web service discovery

Virtual reality simulation in endoscopy training:Current evidence and future directions

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World Journal of Gastroenterology 2018年第48期24卷 5439-5445页

作者： Tahrin Mahmood Michael Anthony Scaffidi Rishad Khan samir ChANDra Grover Division of Gastroenterology St.Michael's HospitalUniversity of Toronto

Virtual reality simulation is becoming the standard when beginning endoscopic training. It offers various benefits including learning in a low-stakes environment, improvement of patient safety and optimization of valuable endoscopy time. This is a review of the evidence surrounding virtual reality simulation and its efficacy in teaching endoscopic techniques. There have been 21 randomized controlled trials(RCTs) that have investigated virtual reality simulation as a teaching tool in endoscopy. 10 RCTs studied virtual reality in colonoscopy, 3 in flexible sigmoidoscopy, 5 in esophagogastroduodenoscopy, and 3 in endoscopic retrograde cholangiopancreatography. RCTs reported many outcomes including distance advanced in colonoscopy, comprehensive assessment of technical and non-technical skills, and patient comfort. Generally, these RCTs reveal that trainees with virtual reality simulation based learning improve in all of these areas in the beginning of the learning process. Virtual reality simulation was not effective as a replacement of conventional teaching methods. Additionally, feedback was shown to be an essential part of the learning process. Overall, virtual reality endoscopic simulation is emerging as a necessary augment to conventional learning given the ever increasing importance of patient safety and increasingly valuable endoscopy time; although work is still needed to study the nuances surrounding its integration into curriculum.

关键词： Endoscopy Gastrointestinal/education Endoscopy Gastrointestinal/standards Simulation Educational measurement Clinical competence/standards Competency-based medical education

Wearable UWB Antenna-Based Bending and Wet Performances for Breast Cancer Detection

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Computers, Materials & Continua 2022年第12期73卷 5575-5587页

作者： Ali Hanafiah Rambe Muzammil Jusoh samir Salem Al-Bawri Mahmoud A.Abdelghany Department of Electrical Engineering Universitas Sumatera UtaraMedan20155Indonesia Advanced Communication Engineering(ACE) Centre of ExcellenceFaculty of Electronic Engineering TechnologyUniversiti Malaysia PerlisMalaysia Department of General Educational Development Faculty of Science and Information Technology(FSIT)Daffodil International UniversityDhaka1341Bangladesh Space Science Centre Climate Change InstituteUniversiti Kebangsaan MalaysiaBangiMalaysia Department of Electronics and Communication Engineering Faculty of EngineeringHadhramout UniversityAl-MukallaYemen Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMinia UniversityMinia61519Egypt

This paper proposed integrating the communication system on the garment,which can be utilized to detect breast cancer at an early stage by using an ultra-wideband(UWB)wearable *** cancer is an abnormal cell that is located in the breast *** detection of breast cancer plays an important role,and it helps in the long term for all *** proposed UWB wearable antenna successfully operates at 3.1-10.6 GHz under an acceptable reflection coefficient of−10 *** fabricated wearable antenna was made from Shieldit Super and felt both conductive and nonconductive wearable *** measurement studies of bending angles have been carried out that covered 2°,4°,6°,8°,and 10°.In addition,the performance of UWB antennas in wet environments is studied in four stages:in water,instantly wet,nearly dry,and entirely *** is good agreement between the measured and simulated *** on the experimental results,the proposed antenna could be helpful for a home breast cancer detection system.

关键词： Wearable antenna UWB antenna bioelectromagnetic antenna propagation

Trends in the hyperfine interactions of magnetic adatoms on thin insulating layers

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npj Computational Materials 2021年第1期7卷 787-796页

作者： Sufyan Shehada Manuel dos Santos Dias Filipe Souza Mendes Guimarães Muayad Abusaa samir Lounis Peter Grünberg Institut and Institute for Advanced Simulation Forschungszentrum Jülich&JARAJülichGermany Department of Physics RWTH Aachen UniversityAachenGermany Jülich Supercomputing Center Forschungszentrum Jülich&JARAJülichGermany Department of Physics Arab American UniversityJeninPalestine Faculty of Physics University of Duisburg-Essen&CENIDEDuisburgGermany

Nuclear spins are among the potential candidates prospected for quantum information technology.A recent breakthrough enabled to atomically resolve their interaction with the electron spin,the so-called hyperfine interaction,within individual atoms utilizing scanning tunneling microscopy(STM).Intriguingly,this was only realized for a few species put on a two-layers thick ***,we systematically quantify from first-principles the hyperfine interactions of the whole series of 3d transition adatoms deposited on various thicknesses of MgO,NaF,NaCl,h–BN,and Cu2N *** identify the adatom-substrate complexes with the largest hyperfine interactions and unveil the main trends and *** reveal the core mechanisms at play,such as the interplay of the local bonding geometry and the chemical nature of the thin films,which trigger transitions between high-and low-spin states accompanied with subtle internal rearrangements of the magnetic *** providing a general map of hyperfine interactions,our work has immediate implications in future STM investigations aiming at detecting and realizing quantum concepts hinging on nuclear spins.

关键词： quantum utilizing breakthrough

Controlled Synthesis of Bismuth Oxyhalides-based Nanomaterials and Their Catalytic Applications

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Controlled Synthesis of Bismuth Oxyhalides-based Nanomateria...

作者： Ahmad samir Karimi Haqmal 北京化工大学

学位级别：硕士

卤氧化铋(BiOX,X=Cl、Br或I)因其独特的结构特性,如二维层状结构和大量暴露的表面原子,而受到广泛关注。这些特性使它们成高效的光催化剂,并被广泛应用于水处理、有机合成等领域。然而,它们在其他催化中的潜力,如作为金属铋的前体或作... 详细信息

卤氧化铋(BiOX,X=Cl、Br或I)因其独特的结构特性,如二维层状结构和大量暴露的表面原子,而受到广泛关注。这些特性使它们成高效的光催化剂,并被广泛应用于水处理、有机合成等领域。然而,它们在其他催化中的潜力,如作为金属铋的前体或作为单原子催化剂的载体,还处于起步阶段。在本论文中,我们研究了卤素离子和形貌对以卤氧化铋为前驱体合成的金属铋电催化剂的结构的影响,及其在氮还原反应(NRR)中的性能,并以氯氧化铋为载体制备了 Pt单原子催化剂,探究了其在苯乙炔反马仕加成硅氢化反应中的催化性能。本论文取得的主要研究成果如下:在第一个工作中,我们发展了一种电还原卤氧化铋制备的金属铋纳米片(BNSs)的合成方法,并将其应用于电催化氮还原反应(NRR)。BNSs可分别由具有不同卤素离子的卤氧化铋纳米片前体以及溴氧化铋纳米棒制备的。X射线衍射(XRD)表征结果显示成功形成了铋纳米片,而电子显微镜表明,以溴氧化铋纳米棒为前驱体制备的BNS1尺寸在70-120纳米之间,以溴氧化铋纳米片为前驱体制备的BNS2尺寸在150-200 nm之间。值得注意的是,在环境温度下,在0.1M Na2SO4水溶液中,在-0.6 VvsRHE时,BNS2的氨产率和法拉第效率分别为3.99 μ gNH3 mgBi-1 h-1和7.04%,而 BNS1 则分别为 2.52 μ gNH3 mgBi-1 h-1 和 4.93%。在第二个工作中,我们采用光沉积策略制备了沉积在氯氧化铋纳米片上的铂单原子催化剂(PtxBOC SAC,该催化剂在苯乙炔的反马氏硅氢化加成反应中表现出优异的催化性能。我们首先合成了氯化氧铋纳米片,然后通过光沉积方法沉积了铂单原子。透射电子显微镜、X射线衍射、X射线光电子能谱、能量色散X射线光谱和CO吸收红外光谱结果表明,铂以单原子的形式均匀分布在氯氧化铋纳米片上。电感耦合等离子体质谱结果表明,铂单原子催化剂的铂负载量在0.5 wt%-4.0 wt%范围内。其中,Pt1BOC在苯乙炔的反马氏氢化硅烷化反应中表现出最高的催化性能,转化频率为156 min-1。该值远高于铂纳米颗粒对比样,也高于文献报道的值。此外,该催化剂表现出优异的稳定性,在5个循环后催化性能没有明显衰减。

关键词：卤氧化铋氮还原反应光沉积单原子催化剂反马尔可夫尼科夫氢硅化化反应

Preparation of ammonium nitrate-based solid composite propellants supplemented with polyurethane/nitrocellulose blends binder and their thermal decomposition behavior

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Defence Technology（防务技术） 2022年第11期18卷 2023-2033页

作者： Sabri Touidjine Moulai Karim Boulkadid Djalal Trache samir Belkhiri Abderrahmane Mezroua Mohamed Islam Aleg Afaf Belkebiche Energetic Propulsion Laboratory Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj-El-Bahri16046AlgiersAlgeria Energetic Materials Laboratory Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj-El-Bahri16046AlgiersAlgeria

To improve the performance of solid composite propellants(SCPs)supplemented with ammonium nitrate(AN)as an oxidizer,the incorporation of energetic ingredients such as explosives,energetic binders or catalysts is a common effective *** this purpose,polyurethane(PU),a typical inert binder,was mixed with nitrocellulose(NC)as an energetic *** composite solid propellant compositions based on AN and NC-modified polyurethane binder with different NC ratios were *** prepared formulations were characterized using Fourier transform infrared spectroscopy(FTIR),RAMAN spectroscopy,X-ray diffraction(XRD),electron densimetry,thermogravimetric(TG)analysis,and differential scanning calorimetry(DSC).A kinetic study was then performed using the iterative KissingerAkahira-Sunose(It-KAS),Flynn-Wall-Ozawa(It-FWO),and non-linear Vyazovkin integral with compensation effect(VYA/CE)*** theoretical performances,such as theoretical specific impulse,adiabatic flame temperature,and ideal exhaust gaseous species,were also determined using the NASA Lewis Code,Chemical Equilibrium with Application(CEA).Spectroscopic examinations revealed the existence of NC and full polymerization of PU in the prepared *** to density tests,the density of the propellant increases as the nitrocellulose component *** to the thermal analysis and kinetics study,the increase in NC content catalyzed the thermal decomposition of the AN-based composite solid *** on the theoretical study,increasing the amount of NC in the propellant increased the specific impulse and,as a result,the overall performance.

关键词： Composite propellants Polyurethane Nitrocellulose Ammonium nitrate Decomposition kinetics Thermal decomposition

Development of new ionic gelation strategy： Towards the preparation of new monodisperse and stable hyaluronic acid/ β-cyclodextrin-grafted chitosan nanoparticles as drug delivery carriers for doxorubicin

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Frontiers of Materials Science 2018年第1期12卷 83-94页

作者： Amina Ben MIHOUB Boubakeur SAIDAT Youssef BAL Celine FROCHOT Regis VANDERESSE samir ACHERAR Laboratoire de Chimie Physique Macromoleculaire (LCPM) Universite de Lorraine-CNRS UMR 7375 1 Rue Grandville BP 2045154001 Nancy Cedex France Laboratory of Physical Chemistry of Materials (LPCM) Faculty of Sciences (UATL) BP 37G Laghouat 03000 Algeria Laboratory of Biomaterials & Transport Phenomena (LBTP) Quartier Ain D'Heb 26000 Medea Algeria Department of Chemistry Faculty of Sciences University Saed Dahleb of Blida (USDB) route de Soumae 09000 Blida Algeria Laboratoire Reactions et Genie des Procedes (LRGP) Universite de Lorraine-CNRS UMR 7274 1 Rue Grandville BP 20451 54001 Nancy Cedex France

In the present study, β-cyclodextrin-grafted chitosan nanoparticles （β-CD- g-CS NPs） were prepared using a new ionic gelation strategy involving a synergistic effect of NaCI （150 mmol/L）, 4-（2-hydroxyethyl）-1-piperazineethanesulfonic acid （HEPES, 10 mmol/L）, and water bath sonication. This new strategy afforded smaller and more monodisperse β-CD-g-CS NPs vs. the classical ionic gelation method. New HA8β-CD-g-CS NPs were also prepared using the above-mentioned strategy by adding hyaluronic acid （HA） to the β-CD-g-CS copolymer at different weight ratios until the ZP values conversion. The best result was obtained with the weight ratio of w（HA）：w（β-CD-g-CS） = 2：1 and furnished new spherical and smooth HA/β-CD-g-CS NPs. Furthermore, the stability of β- CD-g-CS NPs and HA/β-CD-g-CS NPs at 4℃ in physiological medium （pH 7.4） was compared for 3 weeks period and showed that HA/β-CD-g-CS NPs were more stable all maintaining their monodispersity and high negative ZP values compared to β-CD-g-CS NPs. Finally, preliminary study of HA/β-CD-g-CS NPs as carrier for the controlled release of the anticancer drug doxorubicin was investigated. These new HA/β-CD-g-CS NPs can potentially be used as drug delivery and targeting systems for cancer treatment.

关键词： β-cyclodextrin-grafted chitosan hyaluronic acid ionic gelation drugdelivery physicochemical parameters control

Mitochondrial transplantation strategies as potential therapeutics for central nervous system trauma

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Neural Regeneration Research 2018年第2期13卷 194-197页

作者： Jenna L.Gollihue samir P.Patel Alexander G.Rabchevsky Spinal Cord and Brain Iniury Research Center University of KentuckyLexingtonKYUSA Separtment of Physiology University of KentuckyLexingtonKYUSA

Mitochondria are essential cellular organelles critical for generating adenosine triphosphate for cellular homeostasis, as well as various mechanisms that can lead to both necrosis and apoptosis. The field of ＂mi- tochondrial medicine＂ is emerging in which injury/disease states are targeted therapeutically at the level of the mitochondrion, including specific antioxidants, bioenergetic substrate additions, and membrane uncoupling agents. Consequently, novel mitochondrial transplantation strategies represent a potentially multifactorial therapy leading to increased adenosine triphosphate production, decreased oxidative stress, mitochondrial DNA replacement, improved bioenergetics and tissue sparing. Herein, we describe briefly the history of mitochondrial transplantation and the various techniques used for both in vitro and in vivo delivery, the benefits associated with successful transference into both peripheral and central nervous system tissues, along with caveats and pitfalls that hinder the advancements of this novel therapeutic.

关键词： oxygen consumption bioenergetics oxidative phosphorylation cellular uptake replacement strategies spinal cord injury mitochondria

Targeting mitoNEET with pioglitazone for therapeutic neuroprotection after spinal cord injury

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Neural Regeneration Research 2017年第11期12卷 1807-1808页

作者： Alexander G.Rabchevsky samir P.Patel Patrick G.Sullivan Spinal Cord and Brain Injury Research Center University of KentuckyLexingtonKYUSA Departments of Physiology University of KentuckyLexingtonKYUSA Departments of Neuroscience University of KentuckyLexingtonKYUSA Veterans Administration Medical Center University of KentuckyLexingtonK.YUSA

There is mounting evidence that targeting mitochondrial dysfunction following neurotrauma could be key in developing effective therapeutic strategies since mitochondria are known to play a major role in cellular bioenergetics, function, and survival following traumatic spinal cord injury （SCI）（Rabchevsky et al., 2011）. Our research group is one of the pioneers in targeting mitochondrial dysfunction to foster functional neuroprotection, having documented that phar- macological maintenance of mitochondrial function acutely results in long-term neuroprotection and improved function- al recover. We have recently reported that treatment with the pleiotropic drug, pioglitazone, maintains acute mitochondrial integrity correlated with chronic tissue sparing and functional recovery after contusion SCI, but that this was not correlated with altered neuroinflammation （Patel et al., 2017）. We herein propose that the mechanism（s） by which pioglitazone confers neuroprotection may not be entirely dependent upon its activation of peroxisome proliferator activated receptor （PPAR）,

关键词： Targeting mitoNEET therapeutic neuroprotection