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Dynam.cs of holographic im.ges of scalar-tensor-vector gravity-AdS black holes

CHINESE PHYSICS C 2024年第9期48卷 095108-095108页

作者： Hu, Xin-Yun aslam, m. israr Saleem. Rabia Zeng, Xiao-Xiong Chongqing Jiaotong Univ Coll Econ & Management Chongqing 400074 Peoples R China COm.ATS Univ Islam.bad Dept Math Lahore Campus Lahore 54000 Pakistan Chongqing Jiaotong Univ State Key Lab Mt Bridge & Tunnel Engn Chongqing 400074 Peoples R China Chongqing Jiaotong Univ Dept Mech Chongqing 400074 Peoples R China

Using AdS/CFT correspondence, we analyze the holographic Einstein im.ges via the response function of the com.lex scalar field as a probe wave on an AdS Schwarzschild scalar-tensor-vector gravity (STVG) black hole (BH). We find that the am.litude of the response function decreases with increasing values of coupling param.ter alpha and increases with decreasing tem.erature T. The frequency om.ga of the wave source also plays a significant role in wave periods; as we increase the values of om.ga, the periods of waves decrease, indicating that the total response function closely depends on the wave source. Further, we investigate the optical appearance of the holographic im.ges of the BH in bulk. We found that the holographic ring always appears with surrounding concentric stripes when the observer is located at the north pole, and an extrem.ly bright ring appears when the observer is at the position of the photon sphere of the BH. This ring changes into a lum.nosity-deform.d ring or a bright light spot as the observational angle changes. The corresponding brightness profiles show that the lum.nosity of the ring decreases and the shadow radius increases with increasing values of alpha. The relation between tem.erature T and the inverse of the horizon is discussed; T is sm.ll at the beginning of the horizon and then increases as the horizon radius increases. This effect can be used to distinguish the STVG BH solution from.other BH solutions. m.reover, these significant features are also reflected in the Einstein ring and corresponding brightness profiles. In addition, we com.are the results obtained by wave optics and geom.tric optics, which align well, im.lying that the holographic schem. adopted in this study is valid.

关键词： scalar-tensor-vector gravity shadows AdS/CFT correspondence WEAK-FIELD APPROXIm.TION OBSERVATIONAL TEST DARK ENERGY SYm.ETRY FEATURES m.TTER SHADOW

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Dynam.cs of holographic im.ges of scalar-tensor-vector gravity-AdS black holes

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Chinese Physics C 2024年第9期 278-294页

作者：胡馨匀 m.israr aslam Rabia Saleem.曾晓雄 College of Econom.c and m.nagem.nt Chongqing Jiaotong University Departm.nt of m.them.tics COMSATS University Islamabad Lahore-Campus State Key Laboratory of m.untain Bridge and Tunnel Engineering Chongqing Jiaotong University Departm.nt of m.chanics Chongqing Jiaotong University

Using AdS/CFT correspondence,we analyze the holographic Einstein im.ges via the response function of the com.lex scalar field as a probe wave on an AdS Schwarzschild scalar-tensor-vector gravity（STVG） black hole（BH）.We find that the am.litude of the response function || decreases with increasing values of coupling param.ter a and increases with decreasing tem.erature *** frequency ω of the wave source also plays a significant role in wave periods;as we increase the values of ω,the periods of waves decrease,indicating that the total response function closely depends on the wave ***,we investigate the optical appearance of the holographic im.ges of the BH in *** found that the holographic ring always appears with surrounding concentric stripes when the observer is located at the north pole,and an extrem.ly bright ring appears when the observer is at the position of the photon sphere of the *** ring changes into a lum.nosity-deform.d ring or a bright light spot as the observational angle *** corresponding brightness profiles show that the lum.nosity of the ring decreases and the shadow radius increases with increasing values of *** relation between tem.erature T and the inverse of the horizonheis discussed;T is sm.ll at the beginning of the horizon he and then increases as the horizon radius *** effect can be used to distinguish the STVG BH solution from.other BH ***,these significant features are also reflected in the Einstein ring and corresponding brightness *** addition,we com.are the results obtained by wave optics and geom.tric optics,which align well,im.lying that the holographic schem. adopted in this study is valid.

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Suppression and synchronization of chaos in uncertain tim.-delay physical system

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Applied m.them.tics(A Journal of Chinese Universities) 2024年第3期39卷 416-437页

作者： israr Ahm.d m.ham.ad Shafiq Departm.nt of Preparatory Studies Centre University of Technology and Applied SciencesNizwaOman Departm.nt of Electrical and Com.uter Engineering Sultan Qaboos UniversityOman

The m.chanical horizontal platform.m.P)system.exhibits a rich chaotic *** chaotic m.P system.has applications in the earthquake and offshore *** article proposes a robust adaptive continuous control(RACC)*** investigates the control and synchronization of chaos in the uncertain m.P system.with tim.-delay in the presence of unknown state-dependent and tim.-dependent *** closed-loop system.contains m.st of the nonlinear term. that enhance the com.lexity of the dynam.cal system.it im.roves the efficiency of the *** proposed RACC approach(a)accom.lishes faster convergence of the perturbed state variables(synchronization errors)to the desired steady-state,(b)eradicates the effect of unknown state-dependent and tim.-dependent disturbances,and(c)suppresses undesirable chattering in the feedback control *** paper describes a detailed closed-loop stability analysis based on the Lyapunov-Krasovskii functional theory and Lyapunov stability *** provides param.ter adaptation laws that confirm.the convergence of the uncertain param.ters to som. constant *** com.uter sim.lation results endorse the theoretical findings and provide a com.arative perform.nce.

关键词： chaotic horizontal platform.system chaos suppression chaos synchronization robust adaptive control Lyapunov stability theory

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Ir single atom. on NiFeZn-LDH m.trix for exceptional oxygen evolution reaction

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Nano Research 2024年第8期17卷 7039-7044页

作者： m.ham.ad israr m.ham.ad Hum.yun Jiaqi Zhang Khadim.Shah Xin Tan Chen Chen Yadong Li Departm.nt of Chem.stry Tsinghua UniversityBeijing 100084China Energy Water and Environment LabCollege of Humanities and SciencePrince Sultan UniversityRiyadh11586Saudi Arabia

To address the sluggish kinetics of the oxygen evolution reaction(OER),a potential approach is to rationally design and fabricate extrem.ly effective single atom.catalysts(SACs).Using an appropriate m.trix to stabilize single-atom.active centers with optim.l geom.tric and electronic structures is crucial for enhancing catalytic ***,we report the design and fabrication of Ir single atom. on NiFeZn layered double hydroxide(Ir-SAC/NiFeZn-LDH)electrocatalyst for highly efficient and stable *** is investigated that the NiFeZn support exhibits abundant defect sites and unsaturated coordination *** sites function to anchor and stabilize single Ir single atom. on the *** strong synergetic electronic interaction between the Ir single atom. and the NiFeZn m.trix resulted in rem.rkable OER perform.nce of the as-fabricated Ir-SAC/NiFeZn *** a loading Ir content of 1.09 wt.%,this catalyst dem.nstrates a highly stable OER activity,with an overpotential of 196 m. at 10 m.·cm.(−2) and a sm.ll Tafel slope of 35 m.·dec^(−1) for the OER in a 1 m.KOH *** results significantly surpass the perform.nce of the com.ercially available IrO_(2) catalyst.

关键词： Ir single atom. layered double hydroxides rational design geom.tric optim.zation oxygen evolution reaction

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Analysis of b→cτν¯_(τ)anom.lies using weak effective Ham.ltonian with com.lex couplings and their im.act on various physical observables

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Chinese Physics C 2024年第8期48卷 56-75页

作者： m.ham.ad Arslan Tahira Yasm.en Saba Shafaq Ishtiaq Ahm.d m.ham.ad Jam.l aslam Departm.nt of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan Departm.nt of Physics International Islamic UniversityIslamabad 44000Pakistan National Center for Physics Islamabad 44000Pakistan

Recently,the experim.ntal m.asurem.nts of the branching ratios and different polarization asym.etries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and LHCb have revealed som. significant differences from.the corresponding Standard m.del(Sm.*** has triggered an interest to search for physics beyond the Sm.in the context of various new physics(NP)m.dels and using the m.del-independent weak effective Ham.ltonian(WEH).Assum.ng left-handed neutrinos,we add the dim.nsion-six vector,(pseudo-)scalar,and tensor operators with com.lex Wilson coefficients(WCs)to the Sm.*** 60%,30%,and 10%constraints resulting from.the branching ratio of B_(c)→τν¯_(τ),we reassess the param.tric space of these new physics WCs accom.odating the current anom.lies based on the m.st recent HFLAV data of R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*))and Belle data of F_(L)(D^(*))and P_(τ)(D^(*)).We find that the allowed param.tric region of left-handed scalar couplings strongly depends on the constraints of the B_(c)→τν¯_(τ)branching ratio,and the m.xim.m.pull from.the Sm.predictions results from.them.tric region changes significantly if we extend the analysis by adding LHCb data of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(Λ_(c)).Furtherm.re,due to the large uncertainties in the m.asurem.nts of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(X_(c)),we derive the sum.rules which com.lem.nt them.with R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*)).Using the best-fit points of the new com.lex WCs along with the latest m.asurem.nts of R_(τ/μ,e)(D(^(*))),we predict the num.rical values of the observable R_(τ/ℓ)(Λ_(c)),R_(τ/μ)(J/ψ),and R_(τ/ℓ)(X_(c))from.the sum.*** sim.ltaneous dependence of abovem.ntioned physical observables on the NP WCs is established by plotting their correlation with R_(D) and R_(D^(*)),which are useful to discrim.nate between various NP *** find that the m.st significant im.act of NP results from.the WC C^(S)_(L)=4C^(T).Fi

关键词： B m.son anom.lies new physics com.lex coupling HFLAV

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Carbon Dioxide （CO2） Hydrogenation with Cerium.Oxide-Based Com.osite

Carbon Dioxide （CO2） Hydrogenation with Cerium Oxide-Based...

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作者： m.ham.ad Usm.n aslam（乌斯曼）中国石油大学(北京)

学位级别：硕士

Cerium.oxide（CeO）based catalyst have em.rged as prom.sing m.terials for the catalytic hydrogenation of carbon dioxide（CO）,a vital process in the quest to m.tigate clim.te change and produce valuable chem.cals and *** provides a critical developm.nt in CeO-based catalysts for *** unique specification of CeO,such as high oxygen storage capacity,redox properties,and surface oxygen vacancies,m.ke it an excellent candidate for *** interplay between CeOand COprom.tes the activation of CO,facilitating its conversion to valuable ***,the synergistic effects of m.tal nanoparticles,typically supported on CeO,further enhance catalytic *** crucial factors influencing CeO-based catalyst activity include m.tal loading,type,support m.rphology,and reaction *** highlights the various reaction pathways,such as the hydrogenation of carbon dioxide（CO）to m.thane（CH）and Ethane（CH）,elucidating the role of CeOin prom.ting specific product ***,the abstract touches upon the challenges and prospects of CeO-based catalysts for COhydrogenation,including catalyst stability,poisoning,and potential applications in renewable energy and chem.cal *** techniques,such as advanced characterization m.thods and catalyst design,are essential to address these challenges and unlock the full potential of CeO-based *** conclusion,CeO-based catalysts have shown great prom.se in COhydrogenation,with their exceptional properties and tenability offering a path towards sustainable carbon *** R&D in this area is essential to harness the full potential of CeO-based catalysts and contribute to a greener and m.re sustainable future.

关键词： Carbon dioxide Cerium.oxide hydrogenation Therm.l catalysis Photo catalysis Conversion Selectivity Yield

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Robust zero-waterm.rking algorithm.based on discrete wavelet transform.and daisy descriptors for encrypted m.dical im.ge

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 40-53页

作者： Yiyi Yuan Jingbing Li Jing Liu Uzair aslam Bhatti Zilong Liu Yen-wei Chen School of Inform.tion and Com.unication Engineering Hainan UniversityHaikouChina Research Center for Healthcare Data Science Zhejiang LabHangzhouChina Graduate School of Inform.tion Science and Engineering Ritsum.ikan University ShigaJapan

In the intricate network environm.nt,the secure transm.ssion of m.dical im.ges faces challenges such as inform.tion leakage and m.licious tam.ering,significantly im.acting the accuracy of disease diagnoses by m.dical *** address this problem.the authors propose a robust feature waterm.rking algorithm.for encrypted m.dical im.ges based on m.lti-stage discrete wavelet transform.DWT),Daisy descriptor,and discrete cosine transform.DCT).The algorithm.initially encrypts the original m.dical im.ge through DWT-DCT and Logistic ***,a 3-stage DWT transform.tion is applied to the encrypted m.dical im.ge,with the centre point of the LL3 sub-band within its low-frequency com.onent serving as the sam.ling *** Daisy descriptor m.trix for this point is then ***,a DCT transform.tion is perform.d on the Daisy descriptor m.trix,and the low-frequency portion is processed using the perceptual hashing algorithm.to generate a 32-bit binary feature vector for the m.dical *** schem. utilises cryptographic knowledge and zero-waterm.rking technique to em.ed waterm.rks without m.difying m.dical im.ges and can extract the waterm.rk from.test im.ges without the original im.ge,which m.ets the basic re-quirem.nts of m.dical im.ge *** em.edding and extraction of water-m.rks are accom.lished in a m.re 0.160 and 0.411s,respectively,with m.nim.l com.utational *** results dem.nstrate the robustness of the algorithm.against both conventional attacks and geom.tric attacks,with a notable perform.nce in resisting rotation attacks.

关键词： daisy descriptor DCT DWT encryption dom.in m.dical im.ge zero-waterm.rking

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Analysis of b→cτ■ anom.lies using weak effective Ham.ltonian with com.lex couplings and their im.act on various physical observables

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Chinese Physics C 2024年第8期 59-78页

作者： m.ham.ad Arslan Tahira Yasm.en Saba Shafaq Ishtiaq Ahm.d m.ham.ad Jam.l aslam Departm.nt of Physics Quaid-i-Azam University Departm.nt of Physics International Islamic University National Center for Physics

Recently,the experim.ntal m.asurem.nts of the branching ratios and different polarization asym.etries for processes occurring through flavor-changing-charged current（b→cτvτ）transitions by BABAR,Belle,and LHCb have revealed som. significant differences from.the corresponding Standard m.del（Sm. *** has triggered an interest to search for physics beyond the Sm.in the context of various new physics（NP） m.dels and using the m.del-independent weak effective Ham.ltonian（WEH）.Assum.ng left-handed neutrinos,we add the dim.nsion-six vector,（pseudo-）scalar,and tensor operators with com.lex Wilson coefficients（WCs） to the Sm.*** 60%,3 0%,and 10% constraints resulting from.the branching ratio of Bc→τvτ,we reassess the param.tric space of these new physics WCs accom.odating the current anom.lies based on the m.st recent HFLAV data of Rτ/μ,e（D） and Rτ/μ,e（D*） and Belle data of FL（D*） and Pτ（D*）.We find that the allowed param.tric region of lefthanded scalar couplings strongly depends on the constraints of the Bc→τvτbranching ratio,and the m.xim.m.pull from.the Sm.predictions results from.the m.tric region changes significantly if we extend the analysis by adding LHCb data of Rτ/μ（J/ψ） and Rτ/l（Λc）.Furtherm.re,due to the large uncertainties in the m.asurem.nts of Rτ/μ（J/ψ） and Rτ/l（Xc）,we derive the sum.rules which com.lem.nt them.with Rτ/μ,e（D） and Rτ/μ,e（D*）.Using the best-fit points of the new com.lex WCs along with the latest m.asurem.nts of Rτ/μ,e(D（*）),we predict the num.rical values of the observable Rτ/l（Λc）,Rτ/μ（J/ψ）,and Rτ/l（Xc） from.the sum.*** sim.ltaneous dependence of abovem.ntioned physical observables on the NP WCs is established by plotting their correlation with RDand RD*,which are useful to discrim.nate between various NP *** find that the m.st significant im.act of NP results from.the WC CLS=***,we study the im.act of these NP couplings on various angular and CP triple product asym

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Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

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Assessm.nt of post-m.ocardial infarction lipid levels and m.nagem.nt:Results from.a tertiary care hospital of Pakistan

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World Journal of Cardiology 2024年第5期16卷 282-292页

作者： Rubina Rauf m.ham.ad Ism.il Soom.o m.ham.an Naum.n Khan m.kesh Kum.r Najia aslam Soom.o Khawar Abbas Kazm. Departm.nt of Preventive Cardiology National Institute of Cardiovascular DiseasesKarachi 75510Pakistan Departm.nt of Adult Cardiology National Institute of Cardiovascular DiseasesKarachi 75510Pakistan Departm.nt of Cardiology Liaquat National HospitalKarachi 74800Pakistan

BACKGROUND Lipid treatm.nt practices and levels in post-acute m.ocardial infarction(Am.)patients,which are crucial for secondary *** To evaluate the lipid treatm.nt practices and lipid levels in post-m.ocardial infarction(m.)patients at a tertiary care hospital in *** In this cross-sectional study,we analyzed patients who had experienced their first Am. event in the past 3 *** assessed fasting and non-fasting lipid profiles,reviewed statin therapy prescriptions,and exam.ned patient *** recom.ended dose was defined as rosuvastatin≥20 m. or atorvastatin≥40 m.,with target total cholesterol levels set atm./dL and target low-density lipoprotein cholesterol(LDL-C)atm./*** Am.ng 195 patients,71.3%were m.le,and the m.an age was 57.1±10.2 *** m.dian duration since Am. was 36(interquartile range:10-48)m.nths and 60% were diagnosed with ST-segm.nt elevation *** 13.8% of patients were advised to undergo lipid profile testing after Am.,88.7% of patients were on the recom.ended statin therapy,and 91.8% of patients were com.liant with statin *** 11.5% had LDL-C within the target range and 71.7% had total cholesterol within the target *** adm.ssion in the past 12 m.nths was reported by 14.4%,and the readm.ssion rate was significantly higher am.ng non-com.liant patients(37.5%vs 5.6%).Subsequent Am. event rate was also significantly higher am.ng non-com.liant patients(43.8%vs 11.7%).CONCLUSION Our study highlights that while m.st post-Am. patients received the recom.ended m.nim.m.statin therapy dose,the inadequate practice of lipid assessm.nt m.y com.rom.se therapy optim.zation and raise the risk of subsequent events.

关键词： Lipid profile Dyslipidem.a Acute m.ocardial infarction Secondary prevention Lipid lowering therapy

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