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Chinese Chemical Letters 2014年第4期25卷 609-612页

作者： Abdullah G.Al-Sehemi Ahmad Irfan abdullah M.Asiri Department of Chemistry Faculty of ScienceKing Khalid University Unit of Science and Technology Faculty of ScienceKing Khalid University Center of Excellence for Advanced Materials Research King Khalid University Chemistry Department Faculty of ScienceKing Abdulaziz University Center of Excellence for Advanced Materials Research King Abdulaziz University

The title compound exists as yellow （1Y） and red （1R） crystals, but both gave red solutions. The intermolecular interactions between the CN parts of the crystals in IY are very weak. By the mechanical crushing as well as in solution 1Y again becomes red due to the absence of intermolecular interactions. We explain this color behavior by crystallochromism and solvation chromism.

关键词： lntermolecular interactions Crystallochromism Solvation chromism

Au/MXene based ultrafast all-optical switching

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Frontiers of physics 2023年第3期18卷 147-153页

作者： Yule Zhang Feng Zhang Bowen Du Hualong Chen S.Wageh Omar A.al-Hartomy Abdullah G.Al-Sehemi Bin Zhang Han Zhang International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale Optoelectronics and Translational MedicineThe First Affiliated Hospital(Shenzhen Second People’s Hospital)College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Department of Physics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityP.O.Box 9004Ab-ha61413Saudi Arabia

all-optical switches have arisen great attention due to their ultrafast speed as compared with electric switches.However,the excellent optical properties and strong interaction of two-dimensional(2D)material MXene show great potentials in next-generation all-optical switching.As a solution,we propose all-optical switching used Au/MXene with switching full width at half maximum(FWHM)operating at 290 fs.Compared with pure MXene,the Au/MXene behaves outstanding performances due to local surface plasmon resonance(LSPR),including broadband differential transmission,strong near-infrared on/off ratio enhancement.Remarkably,this study enhances understanding of Au/MXene based ultrafast all-optical switching red-shifted about 34 nm in comparison to MXene,validating.all optical properties of Au/MXene opening the way to the implementation of optical interconnection and optical switching.

关键词： Au/MXene ultrafast all-optical switching Au/MXene carrier lifetime

A CRISPR/Cas12a-empowered surface plasmon resonance platform for rapid and specific diagnosis of the Omicron variant of SARS-CoV-2

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National Science Review 2022年第8期9卷 100-109页

作者： Zhi Chen Jingfeng Li Tianzhong Li Taojian Fan Changle Meng Chaozhou Li Jianlong Kang Luxiao Chai Yabin Hao Yuxuan Tang Omar A.al-Hartomy Swelm Wageh Abdullah G.Al-Sehemi Zhiguang Luo Jiangtian Yu Yonghong Shao Defa Li Shuai Feng William J.Liu Yaqing He Xiaopeng Ma Zhongjian Xie Han Zhang Department of Physics Faculty of Science King Abdulaziz University Research Center for Advanced Materials Science (RCAMS) King Khalid University Department of Chemistry College of Science King Khalid University Zhongmin (Shenzhen) Intelligent Ecology Co.Ltd Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Department of Laboratory Medicine Shenzhen Children’s Hospital Optoelectronics Research Center School of Science Minzu University of China NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Research Unit of Adaptive Evolution and Control of Emerging Viruses Chinese Academy of Medical Sciences Institute of Pathogenic Organism Shenzhen Center for Disease Control and Prevention Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics Respiratory Department Shenzhen Children’s Hospital Institute of Pediatrics Shenzhen Children’s Hospital International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education 3. Shenzhen Institute of Translational Medicine 4. Department of Otolaryngology Shenzhen Second People’s Hospital 5. the First Affiliated Hospital 6. Institute of Microscale Optoelectronics Shenzhen University 7. Shenzhen International Institute for Biomedical Research 8. Shenzhen Han’s Tech Limited Company 9. Shenzhen Metasensing Tech Limited Company

The outbreak of the COVID-19 pandemic was partially due to the challenge of identifying asymptomatic and presymptomatic carriers of the virus, and thus highlights a strong motivation for diagnostics with high sensitivity that can be rapidly deployed. On the other hand, several concerning SARS-Co V-2 variants,including Omicron, are required to be identified as soon as the samples are identified as ‘positive’.Unfortunately, a traditional PCR test does not allow their specific identification. Herein, for the first time,we have developed MOPCS(Methodologies of Photonic CRISPR Sensing), which combines an optical sensing technology-surface plasmon resonance(SPR) with the ‘gene scissors’ clustered regularly interspaced short palindromic repeat(CRISPR) technique to achieve both high sensitivity and specificity when it comes to measurement of viral variants. MOPCS is a low-cost, CRISPR/Cas12a-systemempowered SPR gene-detecting platform that can analyze viral RNA, without the need for amplification,within 38 min from sample input to results output, and achieve a limit of detection of 15 fM. MOPCS achieves a highly sensitive analysis of SARS-Co V-2, and mutations appear in variants B.1.617.2(Delta),B.1.1.529(Omicron) and BA.1(a subtype of Omicron). This platform was also used to analyze some recently collected patient samples from a local outbreak in China, identified by the Centers for Disease Control and Prevention. This innovative CRISPR-empowered SPR platform will further contribute to the fast, sensitive and accurate detection of target nucleic acid sequences with single-base mutations.

关键词： surface plasmon resonance CRISPR SARS-CoV-2 Omicron variant

Few-layer Ti_(3)CN MXene for ultrafast photonics applications in visible band

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Journal of Materiomics 2023年第1期9卷 44-55页

作者： Zixin Yang Qi Yang Yulin Tian Xianghe Ren Chun Li Yuqian Zu Syed Zaheer Ud Din Lingfeng gao Jian Wu Hualong Chen Han Zhang Jie Liu Jingliang He abdullah gal-sehemi International School for Optoelectronic Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Edu-cationHangzhou Normal UniversityHangzhou311121China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha410073China Institute of Microscale Optoelectronics College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China Shandong Provincial Engineering and Technical Center of Light Manipulations and Shandong Provincial Key Laboratory of Optics and Photonic Device chool of Physics and ElectronicsShandong Normal UniversityJinan250358China State Key Laboratory of Crystal Materials Shandong UniversityJinan250100China Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbha61413Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityAbha61413Saudi Arabia

Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique properties.However,its ultrafast photonics applications are still rare.Here,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination technique.The nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan technique.The asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of4.05×10^(-2)cm/gW,which was one order of magnitude larger than that of black phosphorus(BP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully realized.Furthermore,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 MHz.The optical modulation device based on few-layer Ti_(3)CN MXene shows good performance.Our work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.

关键词： Ti_(3)CN MXene Z-scan Saturable absorber Optical modulator Pulsed visible lasers

CRISPR-Cas12a-Empowered Electrochemical Biosensor for Rapid and Ultrasensitive Detection of SARS-CoV-2 Delta Variant

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Nano-Micro Letters 2022年第10期14卷 83-94页

作者： Chenshuo Wu Zhi Chen Chaozhou Li Yabin Hao Yuxuan Tang Yuxuan Yuan Luxiao Chai Taojian Fan Jiangtian Yu Xiaopeng Ma Omar Aal-Hartomy SWageh abdullah gal-sehemi Zhiguang Luo Yaqing He Jingfeng Li Zhongjian Xie Han Zhang International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of EducationInstitute of Microscale OptoelectronicsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Shenzhen International Institute for Biomedical Research Shenzhen 518116People’s Republic of China Department of Respiratory Shenzhen Children’s HospitalShenzhen 518038People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038People’s Republic of China Shenzhen Han’s Tech Limited Company Shenzhen 518000People’s Republic of China Hospital of guangzhou Medical University Qingyuan city People’s HospitalQingyuan 511518People’s Republic of China Department of Physics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Zhongmin(Shenzhen)Intelligent Ecology Co. LtdShenzhen 518055People’s Republic of China Shenzhen Center for Disease Control and Prevention Shenzhen 518055People’s Republic of China

Coronavirus disease 2019(COVID-19)is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The gold standard method for the diagnosis of SARS-CoV-2 depends on quantitative reverse transcription-polymerase chain reaction till now,which is time-consuming and requires expensive instrumentation,and the confirmation of variants relies on further sequencing techniques.Herein,we first proposed a robust technique-methodology of electrochemical CRISPR sensing with the advantages of rapid,highly sensitivity and specificity for the detection of SARS-CoV-2 variant.To enhance the sensing capability,gold electrodes are uniformly decorated with electro-deposited gold nanoparticles.Using DNA template identical to SARS-CoV-2 Delta spike gene sequence as model,our biosensor exhibits excellent analytical detection limit(50 fM)and high linearity(R2=0.987)over six orders of magnitude dynamic range from 100 fM to 10 nM without any nucleic-acid-amplification assays.The detection can be completed within 1 h with high stability and specificity which benefits from the CRISPR-Cas system.Furthermore,based on the wireless micro-electrochemical platform,the proposed biosensor reveals promising application ability in point-of-care testing.

关键词： SARS-COV-2 variant Methodology of electrochemical CRISPR sensing(MOECS) gold nanoparticles(AuNPs) Point-of-care testing(POCT)

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr M-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patange P.M.Dighe Sher Singh Meena abdullah gal-sehemi Mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the M-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FESEM profiles of the ferrite samples.The magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.M,and Mossbauer spectroscopy,respectively.The hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity M?ssbauer spectroscopy

3-单酰胺喹唑啉酮衍生物的表征及密度泛函理论研究(英文)

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物理化学学报 2013年第1期29卷 55-63页

作者： al-sehemi abdullah g. al-AMRI Reem S.Abdulaziz IRFAN Ahmad Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia Unit of Science and Technology Faculty of ScienceKing Khalid UniversityAbha 61413P.O.Box 9004Saudi Arabia

Several 3-aminoquinazolin-4-(3H)-one derivatives were synthesized and characterized.Using proton nuclear magnetic resonance (NMR) spectra,we have investigated the barriers to rotation around the N ― N bond as a function of temperature.Changes in the NMR spectra at high temperatures are explained in terms of hindered rotations of the N ― N bond.Free energies of activation for the rate determining stereochemical process were calculated to be as high as 67-75 kJ · mol-1.ground state molecular geometries and vibrational frequencies were calculated using the HF/6-31g and B3LYP/6-31g level of theories.The optimized bond lengths and bond angles are in good agreement with experimental values at both theoretical levels.

关键词：振动频率衍生物化学分析活化自由能

Synthesis and Photooxygenation of Furo[3,2-c]coumarin Derivatives as Antibacterial and DNA Intercalating Agent

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Chinese Journal of Chemistry 2012年第2期30卷 316-320页

作者： al-sehemi,abdullah g. EI-gogary,Sameh R. Chemistry Department Faculty of Science(Abha)King Khaled UniversityKingdom of Saudia Arabia Chemistry Department Faculty of Science(Damietta)Mansoura UniversityEgypt

Syntheses of 2,3-dimethyl-4H-furo[3,2-c]coumarin and 3-phenyl-4H-furo[3,2-c]coumarin as angular furocou- marins were carried out through Williamson reaction of 4-hydroxycoumarin with a-haloketones followed by cycli- zation. Photooxygenation of the synthesized furocoumarin derivatives was performed and the photoproducts were isolated and characterized. The affinity of 2,3-dimethyl-4H-furo[3,2-c]coumarin towards DNA and the antibacterial activity were evaluated and compared with 8-methoxypsoralen （8-MOP）.

关键词： furocoumarins psoralens photooxygenation antibacterial activity and DNA

Complex Permittivity and Permeability Studies Viewing Antenna Applications of NBR-Based Composites Comprising Conductive Fillers

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Materials Sciences and Applications 2018年第11期9卷 883-899页

作者： abdullah g. al-sehemi Ahmed A. al-ghamdi Nikolay T. Dishovsky Nikolay T. Atanasov gabriela L. Atanasova Research Center for Advanced Materials Science (RCAMS) King Khalid University Abha KSA Department of Chemistry College of Science King Khalid University Abha KSA Department of Physics Faculty of Science King Abdulaziz University Jeddah KSA Department of Polymer Engineering University of Chemical Technology and Metallurgy Sofia Bulgaria Department of Telecommunications Faculty of Telecommunications and Management University of Telecommunications and Post Sofia Bulgaria Department of Communication and Computer Engineering Faculty of Engineering South-West University “Neofit Rilski” Blagoevgrad Bulgaria

The work presents studies on the complex permittivity and permeability of composites based on acrylonitrile butadiene rubber containing combinations of conductive fillers which include carbon black and nickel powder. The properties of those composites, containing each of the fillers at the same amount were compared. The permittivity and permeability values of the composites are influenced remarkably by their morphology and structure as well as by the morphological and structural specifics of both fillers. As electron scanning microscopy studies confirm, those parameters are predetermined by the nature of the composites studied—particle size, particles arrangement in the matrix and their tendency to clustering. Last but not least matrix-filler interface phenomena also impact the characteristics in question. The possibilities for applications of the composites in antennae have been studied, in particular, as substrates and insulating layers in flexible antennae for body centric communications (BCCs). The research results allow the conclusion that these materials can find such applications indeed. Composites of higher conductivity can be used where surface waves are generated to provide on-body communications, while composites of lower conductivity may be used for antennae that will be on the body of a person and will transmit to and receive from other antennas that are not on the body of the same person (off-body communications). It is clear that one can engineer the properties of antennae substrates at microwave frequencies by adjusting the filler content and the type of filler and thus control and tailor the antenna performance specific for a particular application.

关键词： NBR Composites Conductive Fillers Antenna Applications Complex Permittivity and Permeability

Frontal lobe position after single-layer cadaveric dermal matrix repair of large anterior skull base defects

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2022年第1期8卷 36-41页

作者： Corinna g.Levine abdullah N.al-Rasheedi alejandro Mantero Mohammad al-Bar Roy R.Casiano Rhinology&Skull Base Surgery Department of OtolaryngologyUniversity of Miami Miller School of MedicineMiamiFloridaUSA Otolaryngology Head&Neck Surgery Jouf University-Medical CollegeSkakaSaudi Arabia Department of Public Health Sciences Biostatistics Collaboration and Consulting Core.MiamiFlorida.USA Otolaryngology King Fahad Hospital of the UniversityImam Abdulrahman Bin Faisal UniversityKhobarSaudi Arabia

Objective:Endoscopic repair of large anterior skull base(ASB)defects has excellent results when using multilayered repairs with a nasoseptal flap.However,in extensive intranasal tumors,a nasoseptal flap may not always be available.One alternative option is a flexible single-layer ASB repair.Initial studies indicate low cerebrospinal fluid leak rates with a single-layer repair.However,the level of frontal lobe support,particularly the propensity for a significant inferior displacement of the frontal lobe,is not known.The g.al of this study is to determine the frontal lobe position after single-layer acellular dermal allograft repair in large ASB defects.Study Design:Retrospective cohort study.Setting:Tertiary care medical center.Subjects and Methods:This cohort study compares the frontal lobe position in adults who underwent endoscopic endonasal ASB tumor resection and single-layer cadaveric dermal matrix repair(ASB cohort)with control subjects without intracranial abnormalities(control cohort).The ASB cohort includes subjects with an ASB defect of≥5 cm anterior/posterior and≥1.5 cm wide and who had imaging at least 2 months after surgery.The frontal lobe position is measured on sagittal CT/MRI using a reference line from the base of the sella to the nasion.A value of zero indicates that the inferior-most aspect of the frontal lobe is at the level of the nasion-sellar line.A positive value indicates that the frontal lobe is inferior to the nasion-sellar line.The ASB cohort frontal lobe position is compared with the control cohort using the Mann-WhitneyU test.A priori we set an absolute difference of 5 mm as a clinically significant difference.Results:The ASB cohort includes 47 subjects who are 57%male with an average age of 60 years(range:31-89 years).The most common ASB pathology is esthesioneuroblastoma(n=21)and 81%of the ASB cohort had postoperative radiation.The control cohort includes 20 subjects who are 60%male,with a mean age of 45 years(range:19-74 years).The majority of controls underwent imaging for head

关键词： anterior skull base cohort study frontal lobe skull base repair skull base tumor