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Chinese Chemical Letters 2023年第4期34卷 608-613页

作者： Yao Li mohammad khurram javed Shu-Qi Wu Arshia Sulaiman Ying-Ying Wu Zhao-Yang Li Osamu Sato Xian-He Bu School of Materials Science and Engineering Nankai UniversityTianjin 300350China Institute for Materials Chemistry and Engineering Kyushu UniversityFukuoka 819-0395Japan

Luminescent spin crossover(SCO) materials have attracted significant interest owing to their potential applications in magneto-optical switches. However, the majority of previously reported FeII-based SCO complexes are adversely affected by fluorescence quenching in the solid-state. Here, we have constructed the first mononuclear FeIIcomplex decorated with an aggregation-induced emission(AIE) luminophore(i.e., tetraphenylethylene) that exhibits synergistic SCO and fluorescence behavior. Intriguingly, we obtained two types of crystals in different solvent systems, both displaying distinct magnetic bistability and fluorescence properties. The fluorescence intensity was observed to track the magnetic susceptibility, which confirmed that SCO and solid-state fluorescence operate synergistically. We introduce a novel approach for the construction of luminescent SCO compounds using an AIEgen as a luminophore, which leads to fluorescence emission in the solid-state, thus allowing us to study the synergy between SCO and fluorescence.

关键词： Magnetic bistability Spin crossover Luminescence Aggregation-induced emission Supramolecular structures

Slow Phase Transition-Induced Scan Rate Dependence of Spin Crossover in a Two-Dimensional Supramolecular Fe(III)Complex

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CCS Chemistry 2023年第2期5卷 412-422页

作者： Zhao-Yang Li Ying-Ying Wu Yao Li Jin-Hua Wang Arshia Sulaiman mohammad khurram javed Ya-Chao Zhang Wei Li Xian-He Bu School of Materials Science and Engineering Nankai UniversityTianjin 300350 Guizhou Provincial Key Laboratory of Computational Nano-Material Science Guizhou Education UniversityGuiyang 550018 College of Chemistry Nankai UniversityTianjin 300071

Spin crossover(SCO)is commonly accompanied by a synchronous phase transition.A few phase transitioncoupled SCO compounds have been reported,yet the synergy between SCO and phase transition on different time scales has not been ***,we report an[Fe(H-5-Cl-thsa-Et)(5-Cl-thsa-Et)]·H2O(1·H2O;H2-5-Cl-thsa-Et=5-chloro-salicylaldehyde ethylthiosemicarbazone)Fe(III)complex that displays a two-dimensional supramolecular structure and SCO behavior above room *** dehydrated form1 exhibits a two-step spin transition with aplateau in the temperature-dependent magnetization(M−T)curve at room temperature and a 51 K thermal hysteresis loop(Tc↑↓=299/248 K)at a rate of 5 K/*** improved SCOperformance in 1 could be attributed to the stronger intralayer but weaker interlayer interactions,which is supported by single-crystal structural analysis and density functional theory ***,complex 1 displays an unusual scan rate-dependent SCO behavior at rates of 0.5−30 K/min,in whichM−T curveplateaus appear at lower scan rates(<10 K/min)but vanish at faster scan rates(≥10 K/min).Scan rate-dependent differential scanning calorimetry,powder X-ray diffractometry,timedependent magnetic moment decays,and infrared spectroscopy consistently reveal that the slow structural relaxation is coupled with a slowcrystallographic phase transition,which is the mechanism for the unusual scan rate-dependent SCO.

关键词： supramolecular two-dimensional structures scan rate dependence spin crossover slow phase transition

Population genetic insights into the conservation of common walnut(Juglans regia)in Central Asia

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Plant Diversity 2024年第5期46卷 600-610页

作者： Linjiang Ye Robabeh Shahi Shavvon Hailing Qi Hongyu Wu Pengzhen Fan mohammad Nasir Shalizi Safiullah khurram Mamadzhanov Davletbek Yerlan Turuspekov Jie Liu CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Key Laboratory of Plant Resources and Biodiversity of Jiangxi Province Jingdezhen UniversityJingdezhen 333400JiangxiChina Germplasm Bank of Wild Species&Yunnan Key Laboratory of Crop Wild Relatives Omics Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Department of Biology Faculty of ScienceYasouj UniversityYasouj 75918-74934Iran University of Chinese Academy of Sciences Beijing 100049China Department of Forestry and Environmental Resources North Carolina State UniversityRaleighNC 27695United States Department of Forestry and Natural Resources Faculty of AgricultureKabul UniversityKabul D-1006Afghanistan National Academy of Science of the Kyrgyz Republic Jalal-Abad Scientific CenterJalal-Abad 715600Kyrgyzstan Laboratory of Molecular Genetics Institute of Plant Biology and BiotechnologyAlmaty 050040Kazakhstan

The common walnut(Juglans regia)is one of the most economically important nut trees cultivated *** its importance,no comprehensive evaluation of walnut tree population genetics has been undertaken across the range where it originated,Central *** this study,we investigated the genetic diversity and population structure of 1082 individuals from 46 populations across Central *** found moderate genetic diversity of *** across Central Asia,with 46 populations clustered into three groups with a weak relationship between genetic and geographic *** findings reveal that the western Himalaya might be the core region of common walnut genetic diversity in Central Asia and that,except for two populations in Gongliu Wild Walnut Valley,humans might have introduced walnut populations to Xinjiang,*** observed distribution of the genetic landscape has probably been affected by historical climate fluctuation,breeding system,and prolonged anthropogenic *** propose the conservation of the core genetic diversity resources in the western Himalaya and pay special attention to populations from Gongliu in *** findings enhance our understanding of the genetic variation throughout the distribution range of *** in Central Asia,which will provide a key prerequisite for evidence-based conservation and management.

关键词： Central Asia Genetic diversity Germplasm management Gongliu wild walnut valley Juglans regia Western Himalaya

SnIP-type atomic-scale inorganic double-helix semiconductors: Synthesis, properties, and applications

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Nano Research 2024年第3期17卷 2111-2128页

作者： Mudussar Ali Bowen Zhang Muhammad khurram Qingfeng Yan Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

Flexible inorganic double helical semiconductors similar to DNA have fueled the demand for efficient materials with innovative structures and excellent *** recent discovery of tin phosphide iodide(SnIP),the first carbon-free double helical semiconductor at an atomic level,has opened new avenues of research for semiconducting devices such as thermoelectric and sensor devices,solar cells,and *** has drawn significant academic attention due to its high structural flexibility,band gap in the visible spectrum range,and non-toxic ***,the recent progress in developing SnIP,including its prestigious structure,versatile and intriguing properties,and synthesis,is *** analogues of SnIP and SnIP-based hybrid materials and their applications in photocatalysis are also ***,the review concludes with a critical summary and future aspects of this new inorganic semiconductor.

关键词： tin phosphide iodide(SnIP) inorganic semiconductor inorganic double helix SnIP-based hybrids photocatalysis flexible material

Impact of scandium and terbium on the mechanical properties,corrosion behavior,and biocompatibility of biodegradable Mg-Zn-Zr-Mn alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 546-572页

作者： khurram Munir Jixing Lin Xian Tong Arne Biesiekierski Yuncang Li Cuie Wen School of Engineering RMIT UniversityMelbourneVictoria 3001Australia School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027China

Magnesium(Mg)-based bone implants degrade rapidly in the physiological environment of the human body which affects their structural integrity and biocompatibility before adequate bone *** earth elements(REEs)have demonstrated their effectiveness in tailoring the corrosion and mechanical behavior of Mg *** study methodically investigated the impacts of scandium(Sc)and terbium(Tb)in tailoring the corrosion resistance,mechanical properties,and biocompatibility of Mg–0.5Zn–0.35Zr–0.15Mn(MZZM)alloys fabricated via casting and hot *** indicate that addition of Sc and Tb improved the strength of MZZM alloys via grain size reduction and solid solution strengthening *** extruded MZZM–(1–2)Sc–(1–2)Tb(wt.%)alloys exhibit compressive strengths within the range of 336–405 MPa,surpassing the minimum required strength of 200 MPa for bone implants by a significant *** polarization tests revealed low corrosion rates of as–cast MZZM(0.25 mm/y),MZZM–2Tb(0.45 mm/y),MZZM–1Sc–1Tb(0.18 mm/y),and MZZM–1Sc–2Tb(0.64 mm/y),and extruded MZZM(0.17 mm/y),MZZM–1Sc(0.15 mm/y),MZZM-2Sc(0.45 mm/y),MZZM-1Tb(0.17 mm/y),MZZM-2Tb(0.10 mm/y),MZZM–1Sc-1Tb(0.14 mm/y),MZZM-1Sc-2Tb(0.40 mm/y),and MZZM–2Sc–2Tb(0.51 mm/y)alloys,which were found lower compared to corrosion rate of high-purity Mg(~1.0 mm/y)reported in the ***,addition of Sc,or Tb,or Sc and Tb to MZZM alloys did not adversely affect the viability of SaOS2 cells,but enhanced their initial cell attachment,proliferation,and spreading shown via polygonal shapes and *** study emphasizes the benefits of incorporating Sc and Tb elements in MZZM alloys,as they effectively enhance corrosion resistance,mechanical properties,and biocompatibility simultaneously.

关键词： Corrosion property In vitro cytotoxicity Magnesium alloys Mechanical property Rare earth elements

Thermal Stability and Strengthening Effect of Coherent Precipitates in a (FeCoNi)_(92)Al_(2.5)Ti_(5.5) High Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1491-1500页

作者： Yuqi Liu Feng Wang Songyang Chen Hui Wang Zhiping Xiong khurram Yaqoob Zhangwei Wang Min Song tate Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China State Key Laboratory for Advance Metals and Materials University of Science and Technology BeijingBeijing100083China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing100081China School of Chemical and Materials Engineering National University of Sciences and TechnologyH-12Islamabad44000Pakistan

The coarsening behavior and strengthening effect of L1_(2)-Ni_(3)(Ti,Al)precipitates in a face-centered-cubic(FCC)(FeCoNi)_(92)Al_(2.5)Ti_(5.5) high entropy alloy have been systematically *** coherent L1_(2) precipitates,uniformly distributed throughout the FCC matrix,consistently retain a spherical *** coarsening rate coefficient of precipitate is determined by employing the Philippe-Voorhees(PV)model,suggesting excellent thermal ***,the elemental partitioning and compositional evolution of the L1_(2) precipitates is analyzed by atom probe tomography,which identify aluminum(Al)as the slowest diffusion species during the coarsening *** addition,the precipitation strengthening effect is quantified to ascertain the optimal size of the *** study enhances the understanding of precipitate coarsening in high entropy alloys,presenting valuable insights into their thermal stability and mechanical properties.

关键词： High entropy alloy L1_(2)precipitates Coarsening kinetics Precipitation hardening

A hyperspectral unmixing approach for ink mismatch detection in unbalanced clusters

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Journal of Information and Intelligence 2024年第2期2卷 177-190页

作者： Faryal Aurooj Nasir Salman Liaquat khurram Khurshid Nor Muzlifah Mahyuddin Department of Electrical Engineering Institute of Space TechnologyIslamabad 44000Pakistan School of Electrical and Electronic Engineering Universiti Sains MalaysiaPenang 14300Malaysia

Detecting ink mismatch is a significant challenge in verifying the authenticity of documents,especially when dealing with uneven ink *** imaging methods frequently fail to distinguish visually similar *** study presents a novel hyperspectral unmixing approach to detect ink mismatches in unbalanced *** proposed method identifies unique spectral characteristics of different inks employing k-means clustering and Gaussian mixture models(GMMs)to perform color segmentation on different ink types and utilizes elbow estimation and silhouette coefficient to evaluate the number of inks estimation *** a more accurate estimation of quantity,which is generally not an attribute of clustering methods,we employed entropy calculations in the red,green,and blue depth channels for precise abundance estimation of *** unique combination of basic techniques in conjunction exhibits better efficacy in performing ink unmixing and provides a real-world document forensic solution compared to current methods that rely on assumptions like prior knowledge of the inks used in a document and deep learning-based methods that rely heavily on abundant training *** evaluate our approach on the ivision handwritten hyperspectral images dataset(iVision HHID),which is a comprehensive and rich dataset that surpasses the commonly-used UWA writing inks hyperspectral images(WIHSI)database in size and *** study has accomplished the unmixing task with three main challenges:unmixing of diverse ink spectral signatures(149 spectral bands instead of 33 bands in the previous dataset),without using prior knowledge and assumptions about the number of inks used in the questioned document,and not requiring large training data for performing ***,the security of the proposed document authentication methodology to address the likelihood of forgeries or manipulations in questioned documents is enhanced as compared to previous works relyin

关键词： k-means clustering Gaussian mixture model(GMM) Hyper spectral imaging(HSI) iVision handwritten hyperspectral images dataset(HHID) Document forensics

Mechanical and corrosion properties of graphene nanoplatelet–reinforced Mg–Zr and Mg–Zr–Zn matrix nanocomposites for biomedical applications

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Journal of Magnesium and Alloys 2022年第2期10卷 495-514页

作者： mohammad Shahin Cuie Wen khurram Munir Yuncang Li School of Engineering RMIT UniversityMelbourneVictoria 3001Australia

Magnesium(Mg)-based biomaterials have gained acceptability in fracture fixation due to their ability to naturally degrade in the body after fulfilling the desired ***,pure Mg not only degrades rapidly in the physiological environment,but also evolves hydrogen gas during *** this study,Mg0.5Zr and Mg0.5ZrxZn(x=1–5 wt.%)matrix nanocomposites(MNCs)reinforced with different contents(0.1–0.5 wt.%)of graphene nanoplatelets(GNP)were manufactured via a powder metallurgy technique and their mechanical and corrosion properties were *** increase in GNP concentration from 0.2 wt.%to 0.5 wt.%added to Mg0.5Zr matrices resulted in decreases in the compressive yield strength and corrosion resistance in Hanks’Balanced Salt Solution(HBSS).On the other hand,a higher concentration(4–5 wt.%)of Zn added to Mg0.5Zr0.1GNP resulted in an increase in ductility but a decrease in compressive yield ***,an addition of 0.1 wt.%GNPs to Mg0.5Zr3Zn matrices gave excellent ultimate compressive strength(387 MPa)and compressive yield strength(219 MPa).Mg0.5Zr1Zn0.1GNP and Mg0.5Zr3Zn0.1GNP nanocomposites exhibited 29%and 34%higher experimental yield strength,respectively,as compared to the theoretical yield strength of Mg0.5Zr0.1GNP calculated by synergistic strengthening mechanisms including the difference in thermal expansion,elastic modulus,and geometry of the particles,grain refinement,load transfer,and precipitation of GNPs in the Mg *** corrosion rates of Mg0.5Zr1Zn0.1GNP,Mg0.5Zr3Zn0.1GNP,Mg0.5Zr4Zn0.1GNP,and Mg0.5Zr5Zn0.1GNP measured using potentiodynamic polarization were 7.5 mm/y,4.1 mm/y,6.1 mm/y,and 8.0 mm/y,***,hydrogen gas evolution tests also demonstrated that Mg0.5Zr3Zn0.1GNP exhibited a lower corrosion rate(1.5 mm/y)than those of Mg0.5Zr1Zn0.1GNP(3.8 mm/y),Mg0.5Zr4Zn0.1GNP(1.9 mm/y),and Mg0.5Zr5Zn0.1GNP(2.2 mm/y).This study demonstrates the potential of GNPs as effective nano-reinforcement particulates for improv

关键词： Biodegradation Graphene nanoplatelet Magnesium metal matrix composite Mg–Zr–Zn alloy Strengthening mechanism

Nano-tribological behavior of graphene nanoplatelet-reinforced magnesium matrix nanocomposites

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Journal of Magnesium and Alloys 2021年第3期9卷 895-909页

作者： mohammad Shahin khurram Munir Cuie Wen Yuncang Li School of Engineering RMIT UniversityMelbourneVIC 3001Australia

The corrosion resistance and wear resistance of metallic biomaterials are critically important for orthopedic hard-tissue replacement applications because the lack of such properties not only adversely affects their mechanical integrity but also allows the release of wear debris into the human *** this study,the potential of zirconium(Zr)as an alloying element and graphene nanoplatelets(GNPs)as a nano-reinforcement material were investigated in relation to improving the tribological performance of pure magnesium(Mg).The GNPs-reinforced Mg matrix nanocomposites(MNCs)were fabricated using powder *** indicate that additions of 0.5 wt.%Zr and0.1 wt.%GNPs to Mg matrices significantly improved the wear resistance by 89%and 92%at 200μN load,60%and 80%at 100μN load,and 94%and 93%at 50μN load,respectively,as compared to the wear resistance of pure *** wear depth and coefficient of friction of the MNC containing 0.5 wt.%Zr and 0.1 wt.%GNPs(Mg0.5 Zr0.1 GNPs MNC)were considerably reduced as compared to pure Mg and Mg0.5 *** results demonstrate that the Mg0.5 Zr0.1 GNPs MNC is promising for orthopedic applications in relation to its excellent tribological performance.

关键词： Coefficient of friction Graphene nanoplatelet Magnesium matrix nanocomposite Wear

Hypersonic reentry trajectory planning by using hybrid fractional-order particle swarm optimization and gravitational search algorithm

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Chinese Journal of Aeronautics 2021年第1期34卷 50-67页

作者： khurram SHAHZAD SANA Weiduo HU School of Astronautics Beihang UniversityBeijing 102206China

This paper proposes a novel hybrid algorithm called Fractional-order Particle Swarm optimization Gravitational Search Algorithm(FPSOGSA)and applies it to the trajectory planning of the hypersonic lifting reentry flight *** proposed method is used to calculate the control profiles to achieve the two objectives,namely a smoother trajectory and enforcement of the path constraints with terminal *** smoothness of the trajectory is achieved by scheduling the bank angle with the aid of a modified scheme known as a Quasi-Equilibrium Glide(QEG)*** aerodynamic load factor and the dynamic pressure path constraints are enforced by further planning of the bank angle with the help of a constraint enforcement *** maximum heating rate path constraint is enforced through the angle of attack *** Common Aero Vehicle(CAV)flight vehicle is used for the simulation purpose to test and compare the proposed method with that of the standard Particle Swarm Optimization(PSO)method and the standard Gravitational Search Algorithm(GSA).The simulation results confirm the efficiency of the proposed FPSOGSA method over the standard PSO and the GSA methods by showing its better convergence and computation efficiency.

关键词： Fractional-order Gravitational search algorithm Particle swarm optimization Reentry gliding vehicle Trajectory optimization