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Framework for Secure Substitution Box Construction and Its Application in Image Encryption
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作者 Umar Hayat Ikram Ullah Muhammad Bilal 《Computers, Materials & Continua》 2026年第4期1428-1462,共35页
Elliptic curve(EC)based cryptosystems gained more attention due to enhanced security than the existing public key cryptosystems.A substitution box(S-box)plays a vital role in securing modern symmetric key cryptosystem... Elliptic curve(EC)based cryptosystems gained more attention due to enhanced security than the existing public key cryptosystems.A substitution box(S-box)plays a vital role in securing modern symmetric key cryptosystems.However,the recently developed EC based algorithms usually trade off between computational efficiency and security,necessitating the design of a new algorithm with the desired cryptographic strength.To address these shortcomings,this paper proposes a new scheme based onMordell elliptic curve(MEC)over the complex field for generating distinct,dynamic,and highly uncorrelated S-boxes.Furthermore,we count the exact number of the obtained S-boxes,and demonstrate that the permuted version of the presented S-box is statistically optimal.The nonsingularity of the presented algorithm and the injectivity of the resultant output are explored.Rigorous theoretical analysis and experimental results demonstrate that the proposedmethod is highly effective in generating a large number of dynamic S-boxes with adequate cryptographic properties,surpassing current state-of-the-art S-box generation algorithms in terms of security.Apart fromthis,the generated S-box is benchmarked using side-channel attacks,and its performance is compared with highly nonlinear S-boxes,demonstrating comparable results.In addition,we present an application of our proposed S-box generator by incorporating it into an image encryption technique.The encrypted and decrypted images are tested by employing extensive standard security metrics,including the Number of Pixel Change Rate,the Unified Average Changing Intensity,information entropy,correlation coefficient,and histogram analysis.Moreover,the analysis is extended beyond conventional metrics to validate the new method using advanced tests,such as the NIST statistical test suite,robustness analysis,and noise and cropping attacks.Experimental outcomes show that the presented algorithm strengthens the existing encryption scheme against various well-known cryptographic attacks. 展开更多
关键词 substitution box Mordell elliptic curve Mobius transformation NONLINEARITY image encryption CRYPTANALYSIS data security
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Relationship between 24-hour activity behaviors and depression in older adults with multimorbidity using the isotemporal substitution model:A cross-sectional study
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作者 Pei-Ya Tao Ju-Feng Chen +3 位作者 Yu-Xi Chen Sunanjie Zhao Guo-Hu Han Zhuo Wang 《Nursing Communications》 2026年第5期1-9,共9页
Background:The phenomenon of multimorbidity in chronic diseases among the elderly is prevalent,and its significant association with depression poses a serious threat to the physical and mental health of older adults.C... Background:The phenomenon of multimorbidity in chronic diseases among the elderly is prevalent,and its significant association with depression poses a serious threat to the physical and mental health of older adults.Current research on the associations between 24-hour movement behaviors(including physical activity,sedentary behavior,and sleep)and depression has largely been confined to examining the effects of single behaviors,overlooking the intrinsic compositional nature and interrelationships among these behaviors.Therefore,it is necessary to investigate the integrated effects of 24-hour movement behaviors on depression in older adults with multimorbidity from a holistic,compositional perspective.Methods:From November 2024 to April 2025,a total of 226 older adult patients with multimorbidity were recruited from a tertiary hospital in Changzhou City.Data were collected using a general information questionnaire,the International Physical Activity Questionnaire–Short Form(IPAQ-SF),the Pittsburgh Sleep Quality Index(PSQI),and the Patient Health Questionnaire-9(PHQ-9).Compositional data analysis and isotemporal substitution models were employed for statistical analysis.Results:The mean daily durations of Light-Intensity Physical Activity(LPA),Moderate-to-Vigorous Physical Activity(MVPA),Sedentary Behavior(SB),and Sleep(SLP)in older adults with multimorbidity were 402.48 min,12.04 min,511.52 min,and 458.68 min,respectively.The prevalence of depressive symptoms was 37.6%.Compositional data analysis revealed that SB was positively associated with depression(βSB=1.005,P=0.006),while SLP was negatively associated with depression(βSLP=−1.736,P<0.001).No statistically significant associations were found between MVPA or LPA and depression(P>0.05).In the 10-minute isotemporal substitution model,replacing SB with any other behavioral component was associated with a decrease in depression scores.Conversely,substituting SLP with either LPA or SB resulted in an increase in depression scores,while substituting SLP with MVPA led to a decrease in depression scores.The dose-response analysis revealed that,among the isotemporal substitution effects,replacing SB with SLP and replacing SLP with MVPA were the substitution pathways associated with the most rapid decline in depression scores,representing the greatest beneficial health effects.Conclusion:The prevalence of depression is notably high among older adults with multimorbidity.Reducing daily sedentary behavior(SB),maintaining adequate sleep(SLP),and increasing moderate-to-vigorous physical activity(MVPA)can improve depressive symptoms and enhance overall health in this population. 展开更多
关键词 24-hour activity behaviors isotemporal substitution model compositional data analysis MULTIMORBIDITY DEPRESSION older adults
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Violet Arsenic Phosphorus:Switching p-Type into High Performance n-Type Semiconductor by Arsenic Substitution
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作者 Rui Zhai Zhuorui Wen +7 位作者 Xuewen Zhao Junyi She Mengyue Gu Fanqi Bu Chang Huang Guodong Meng Yonghong Cheng Jinying Zhang 《Nano-Micro Letters》 2026年第5期93-106,共14页
Violet phosphorus,a recently explored layered elemental semiconductor,has attracted much attention due to its unique photoelectric,mechanical properties,and high hole mobility.Herein,violet arsenic phosphorus has for ... Violet phosphorus,a recently explored layered elemental semiconductor,has attracted much attention due to its unique photoelectric,mechanical properties,and high hole mobility.Herein,violet arsenic phosphorus has for the first time been synthesized by a molten lead method.The crystal structure of violet arsenic phosphorus(P^(83.4)As_(0.6),CSD-2408761)was determined by single crystal X-ray diffraction to have similar structure as that of violet phosphorus,where P12 is occupied by arsenic/phosphorus(As/P)atoms as mixed occupancy sites As1/P12.The arsenic substitution has been demonstrated to tune the band structure of violet phosphorus,switching p-type of violet phosphorus to high-performance n-type violet arsenic phosphorus.The effective electron mass along the<010>direction is significantly reduced from 1.792 to 0.515 m_(0)by arsenic substitution,resulting in an extremely high electron mobility of 2622.503 cm^(2)V^(-1)s^(-1).The field effect transistor built with P_(83.4)As_(0.6)nanosheets was measured to have a high electron mobility(137.06 cm^(2)V^(-1)s^(-1),61.2 nm),even under ambient conditions for 5 h,much higher than the hole mobility of violet phosphorene nanosheets(4.07 cm^(2)V^(-1)s^(-1),73.3 nm).This work provides a new idea for designing phosphorus-based materials for field effect transistors,giving significant potential in complementary metal-oxide-semiconductor applications. 展开更多
关键词 Violet phosphorus Arsenic substitution n-type semiconductor High mobility Field effect transistor
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Cytogenetic characterization and molecular marker development of a novel wheat-Thinopyrum ponticum 5E(5D)disomic substitution line with resistance to powdery mildew and stripe rust
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作者 Xiaofang Cheng Yi Xiao +7 位作者 Luhui Wang Xiaoying Yang Pingchuan Deng Jixin Zhao Changyou Wang Chunhuan Chen Tingdong Li Wanquan Ji 《Journal of Integrative Agriculture》 2026年第1期30-41,共12页
Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to bioti... Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to biotic and abiotic stresses.This study focused on the CH97 line,derived from the BC1F7 progeny of a cross between wheat cv.7182 and Th.ponticum.Cytological evidence showed that CH97 has 42 chromosomes,forming 21 bivalents at meiotic metaphase I,with the bivalents subsequently separating and moving to opposite poles during meiotic anaphase I.Through a combination of fluorescence in situ hybridization(FISH),genomic in situ hybridization(GISH),multicolor GISH(mc-GISH),and liquid array analysis,it was determined that CH97 comprises 40 wheat chromosomes and two alien chromosomes from the Ee genome of Th.ponticum,featuring the absence of a pair of 5D chromosomes and variations in 1B,6B,and 7B chromosomes.These findings confirm that CH97 is a stable wheat-Th.ponticum 5E(5D)alien disomic substitution line.Inoculation experiments revealed that CH97 exhibits high resistance to wheat powdery mildew and stripe rust throughout the growth period,in contrast to the highly susceptible common wheat parent 7182.Compared to 7182,CH97 displayed improvements in thousand-kernel weight and kernel length.Additionally,utilizing specific-locus amplified fragment sequencing(SLAF-seq)technology,chromosome 5E-specific molecular markers were developed and validated,achieving a 33.3% success rate,facilitating marker-assisted selection for disease resistance in wheat.Overall,the CH97 substitution line,with its resistance to diseases and improved agronomic traits,represents valuable new germplasm for wheat chromosome engineering and breeding. 展开更多
关键词 Thinopyrum ponticum disomic substitution line powdery mildew stripe rust SLAF-seq liquid array
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Base-Catalyzed Chemoselective Substitution ofβ-Ketonitrile with Azodicarboxylates
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作者 Guo Yishi Sang Tian +1 位作者 Liu Yan Liu Ping 《有机化学》 北大核心 2025年第4期1249-1260,共12页
Base-catalyzed nucleophilic substitution reactions ofβ-ketonitrile with azodicarboxylates have been developed.A series of disubstituted C—N coupling products were obtained in good to excellent yields under Et_(3)N c... Base-catalyzed nucleophilic substitution reactions ofβ-ketonitrile with azodicarboxylates have been developed.A series of disubstituted C—N coupling products were obtained in good to excellent yields under Et_(3)N catalysis.Monosubstitu-tion C—N bond formation reaction catalyzed by K_(2)CO_(3) also gave novel enol-based target products.This method is simple and mild,with good chemoselectivity,excellent substrate compatibility and tolerance for various functional groups,and achieves gram-scale synthesis.The reaction is a nucleophilic substitution process without the involvement of free radicals. 展开更多
关键词 base-catalysis β-ketonitrile selective substitution AZODICARBOXYLATE
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A substitution measurement for cross section of ^(65)Cu(γ,n)^(64)Cu reaction using ^(nat)Cu and ^(63)Cu targets by quasi-monoenergetic γ beams at SLEGS
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作者 Pu Jiao Zi-Rui Hao +18 位作者 Zhi-Cai Li Qian-Kun Sun Long-Xiang Liu Hang-Hua Xu Yue Zhang Meng-Die Zhou Wen Luo Yu-Xuan Yang Sheng Jin Kai-Jie Chen Shan Ye Zhen-Wei Wang Yu-Ting Wang Hui-Ling Wei Yao Fu Kun Yu Hong-Wei Wang Gong-Tao Fan Chun-Wang Ma 《Nuclear Science and Techniques》 2025年第12期294-303,共10页
To overcome the difficulty and high cost of some specific isotopic targets,a substitution method was proposed to measure the cross section of the(γ,n)reactions.Considering that the natural copper element(^(nat)Cu)onl... To overcome the difficulty and high cost of some specific isotopic targets,a substitution method was proposed to measure the cross section of the(γ,n)reactions.Considering that the natural copper element(^(nat)Cu)only has^(63)Cu and^(65)Cu isotopes,the^(65)Cu(γ,n)^(64)Cu reaction was taken as an example to test the substitution method.Using quasi-monoenergeticγbeams provided by the Shanghai Laser Electron Gamma Source(SLEGS)of the Shanghai Synchrotron Radiation Facility(SSRF),^(nat)Cu(γ,n)was measured from E_(γ)=11.09 MeV to 17.87 MeV.Furthermore,based on the^(63)Cu(γ,n)reaction measured using the same experimental setup at SLEGS,^(65)Cu(γ,n)^(64)Cu was extracted using the substitution method.The abundance variation of natural copper,showing a significant influence on the cross section,was also investigated.The results were compared to the existing experimental data measured by bremsstrahlung and positron annihilation in-flight sources,and the TALYS 2.0 predictions.Theγstrength function(γSF)of^(65)Cu was obtained from the^(65)Cu(γ,n)data,and the reaction cross section of^(64)Cu(n,γ)was further calculated. 展开更多
关键词 Photoneutron cross section Flat-efficiency detector Laser Compton scattering γrays SLEGS substitution measurement Copper isotopes
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Isoelectronic Ga Substitution Effects on Antiferromagnetic Order in CeRh(In_(1-x)Ga(_x))_(5)
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作者 Xin Li Kai Wen Chen +6 位作者 Cheng Yu Jiang Jia Chen Jiao Mu Yuan Zou Oksana Zaharko Bai Jiang Lv Guang-Ai Sun Lei Shu 《Chinese Physics Letters》 2025年第8期168-174,共7页
In this work,Ga-doped Ce RhIn_(5) single crystals are grown by In/Ga flux method.Single-crystal X-ray diffraction,magnetic susceptibility,specific heat,and neutron diffraction measurements are utilized to characterize... In this work,Ga-doped Ce RhIn_(5) single crystals are grown by In/Ga flux method.Single-crystal X-ray diffraction,magnetic susceptibility,specific heat,and neutron diffraction measurements are utilized to characterize the sample quality and the antiferromagnetic transition temperature T_(N).By substituting In with Ga,T_(N) is slightly decreased,but the antiferromagnetic transition peaks in magnetic susceptibility and specific heat measurements are obviously broadened by external field along c-axis.By comparing with Zn-doped Ce RhIn_(5),it can be concluded that T_(N) is dominated by electron density,and the stiffness of antiferromagnetic transition is obviously reduced by Ga substitution.The substitution effects of Ga are possibly caused by forming heterogeneous local structures,which avoids quantum critical point,superconductivity,and non-Fermi liquid states.Investigations on Gadoped Ce RhIn_(5) help to comprehend the chemical substitution effects in Ce RhIn_(5),and the interaction between heterogeneous structure and long-range antiferromagnetic states. 展开更多
关键词 antiferromagnetic order isoelectronic substitution antiferromagnetic transition peaks antiferromagnetic transition temperature Ga doping external field magnetic susceptibility neutron diffraction measurements
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Influence of life-history traits on mitochondrial DNA substitution rates exceeds that of metabolic rates in teleost fishes
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作者 Yangyang Jing Rui Long +5 位作者 Juanzhu Meng Ya Yang Xinyi Li Bairu Du Ayesha Naeem Yiping Luo 《Current Zoology》 2025年第3期284-294,共11页
Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristi... Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristics and both resting and maximal MRs in conjunction with life-history traits among 139 species of teleost fish,We gathered fish MR data from various sources and procured sequences of 13 mitochondrial protein-encoding genes.We calculated the absolute substitution rate for entire nucleotide sequences and 4-fold degenerate sites of each gene,along with encoding amino acid sequences.Using the phylogenetic comparative method,we then explored the associations between MR and mitochondrial DNA absolute substitution rate.Additionally,we screened MR-associated single nucleotide variants in mitochondrial DNA.The findings indicate no positive correlation between MRs and any substitution rate values of both combined sequences and individual mitochondrial protein-coding genes,refuting the MR hypothesis.Instead,both maximum body size and longevity correlated negatively with molecular substitution rates,suggesting their influences on both mutation and fixation within mitochondrial genes in fish.Results also revealed significant correlations between base variation at ATP6_169 and both resting MR and maximum MR,identifying the unique ATP6_169G in Scombridae fish,which results in an extremely low isoelectric point(pl)value of the ATP6 protein.Considering its functional significance,the ATP6_169G in Scombridae fish might link to their lifestyle characterized by fast locomotion and high metabolic demands alongside a slower molecular evolutionary rate. 展开更多
关键词 FISH metabolic rate mitochondrial genes substitution sites single nucleotide variant
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Hyaluronic acid conjugates with controlled oleic acid substitution as new nanomaterials for improving ocular co-delivery of cyclosporine A and oleic acid
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作者 Hai V.Ngo Hy D.Nguyen Beom-Jin Lee 《Asian Journal of Pharmaceutical Sciences》 2025年第1期164-182,共19页
A structural conjugate(HOC)of polysaccharide,hyaluronic acid(HA)with different ratios of oleic acid(OA)via cystamine(CYS)linker as a new ocular biomaterial was developed.The HOCs with controlled degrees of substitutio... A structural conjugate(HOC)of polysaccharide,hyaluronic acid(HA)with different ratios of oleic acid(OA)via cystamine(CYS)linker as a new ocular biomaterial was developed.The HOCs with controlled degrees of substitution of OA(4.6%,8.3%and 12.2%)were synthesized to form self-assembled HA-CYS-OA nanoparticles(HONs,HON1,HON2,HON3).A poorly water-soluble cyclosporine A(CsA)to be used for the treatment of multifactorial dry eye disease(DED)was chosen as model drug.CsA-loaded HONs exhibited improved solution transparency via solubilizing capacity of HON,and increased in vitro drug permeation compared to Restasis®.The physicochemical properties of CsA-loaded HONs such as nano behaviors,solution transparency,drug release,drug permeation and ocular cytocompatibility were highly variable according to the ratios of OA substitution.Interestingly,this CsA-loaded HON1 as optimal ocular nanoformulation showed markedly augmentedmacrophage polarization into the M2 phenotype,downregulated the expression of proinflammatory cytokines levels in LPS-induced M1 macrophage,and effectively inhibited VEGF-induced endothelial cell proliferation and capillary-like tube formation by the synergistic effect of CsA and HON1 containing OA at the same time.Collectively,the current fatty acid conjugated to HA,named fattigation platform,providing the roles and physicochemical properties via structural features of HA could be a promising co-delivery strategy of drug and fatty acid for DED and other ophthalmic disease treatments. 展开更多
关键词 Hyaluronic acid conjugates Controlled oleic acid substitution Self-assembled nanomaterial Cyclosporine A Ocular co-delivery Synergistic effects
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Isomorphous substitution in CaAl-hydrotalcite to construct high density single-atom catalysts for selective N-Heteroarene hydrogenation
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作者 Jieting He Yu Liang +4 位作者 Binbin Zhao Lei Liu Qian He Dingsheng Wang Jinxiang Dong 《Chinese Journal of Catalysis》 2025年第3期353-362,共10页
Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such ... Metal oxides as support for constructing precious metal single-atom catalysts hold great promise for a wide range of industrial applications,but achieving a high-loading of thermally stable metal single atoms on such supports has been challenging.Herein,we report an innovative strategy for the fabrication of high-density single-atoms(Rh,Ru,Pd)catalysts on CaAl-layered double hydroxides(CaAl-LDH)via isomorphous substitution.The Rh species have occupied Ca^(2+)vacancies within CaAl-LDH laminate by ion-exchange,facilitating a substantial loading of isolated Rh single-atoms.Such catalysts displayed superior performance in the selective hydrogenation to quinoline,pivotal for liquid organic hydrogen storage,and the universality for the hydrogenation of N-heterocyclic aromatic hydrocarbons was also verified.Combining the experimental results and density functional theory calculations,the pathway of quinoline hydrogenation over Rh1CaAl-LDH was proposed.This synthetic strategy marks a significant advancement in the field of single-atom catalysts,expanding their horizons in green chemical processes. 展开更多
关键词 Isomorphous substitution High-loading Single-atom catalyst Selective hydrogenation
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Enabling durable sodium storage of Fe-based fluorophosphate cathode via anion substitution
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作者 Zheng Li Zechen Li +3 位作者 Yanzhe Zhang Xuanyi Yuan Haibo Jin Yongjie Zhao 《Journal of Energy Chemistry》 2025年第10期850-858,共9页
Na_(2)FePO_(4)F is a promising sodium ion cathode due to its low cost,non-toxicity,and high stability.However,the sluggish Na^(+)diffusion kinetics and limited intrinsic electronic conductivity critically restrict its... Na_(2)FePO_(4)F is a promising sodium ion cathode due to its low cost,non-toxicity,and high stability.However,the sluggish Na^(+)diffusion kinetics and limited intrinsic electronic conductivity critically restrict its worldwide application.Herein,an anion-substitution strategy is proposed with SiO_(4)^(4-)as the dopant.SiO_(4)^(4-)substitution for PO_(4)^(3-)can apparently alter the localized electronic density and structural configuration in the lattice of Na_(2)FePO_(4)F,effectively elevating the charge transfer efficiency.As a result,the electrochemical reaction kinetics of Na_(2)FePO_(4)F is significantly enhanced,which is well demonstrated by a series of electrochemical characterizations.As-obtained Na_(2.2)Fe(PO_(4))_(0.8)(SiO_(4))_(0.2)F renders a specific capacity of 84.9 m A h g^(-1)within the region of 2.5-4.0 V at 60 mA g^(-1)(0.5 C),good rate capability,and a capacity retention of 70.0% after 1000 cycles at 1.24 A g^(-1)(10 C).Furthermore,the stabilities of the cathode-electrolyte interface and structure are strengthened,which are verified by in situ EIS and ex situ XRD analysis.These findings highlight silicate anion substitution as a promising and cost-effective strategy for overcoming the limitations of Na_(2)FePO_(4)F,contributing to the development of sustainable energy storage solutions. 展开更多
关键词 Sodium ion cathode Anion substitution Enhanced diffusion kinetics Cycling stability Rate capability
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Catalytic construction of P-stereogenic center via phosphorus-centered nucleophilic substitution
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作者 Bingbing Dong Junmin Zhang +2 位作者 Xiang-Yu Ye Xuan Huang Yonggui Robin Chi 《Chinese Chemical Letters》 2025年第9期26-33,共8页
P-stereogenic compounds play pivotal roles in natural products,pharmaceuticals,bioactive molecules,and catalysts/ligands,making their synthesis a highly researched area.Current studies have predominantly concentrated ... P-stereogenic compounds play pivotal roles in natural products,pharmaceuticals,bioactive molecules,and catalysts/ligands,making their synthesis a highly researched area.Current studies have predominantly concentrated on fully carbon-substituted P-stereogenic species,despite the fact that many therapeutically relevant compounds feature P-O,P-N,or P-S bonds.The catalytic and stereoselective nucleophilic substitution at the P-center is acknowledged as a highly efficient and straightforward approach for constructing high-value P-stereogenic compounds,offering significant potential for further development.This review provides an overview of advancements in the construction of P-stereogenic centers based on Pcentered nucleophilic substitution,highlighting key challenges,breakthroughs,and future opportunities in the field. 展开更多
关键词 P-stereogenic compounds P-stereogenic ProTides P-centered nucleophilic substitution Dynamic kinetic transformation Asymmetric catalysis
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Complex-mediated nucleophilic aromatic substitution with aryl nitriles to realize intramolecular flapping-restricted D-A AIEgens for bioimaging
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作者 Feng Liu Junkai Liu +10 位作者 Junyi Gong Runfeng Lin Siyuan Qiu Zicheng Liu Chongyang Li Miao Meng Shijie Li Mei Tu Jacky WYLam Guangle Niu Ming Chen 《Smart Molecules》 2025年第2期72-82,共11页
Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free m... Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free method by a complexmediated nucleophilic aromatic substitution of aryl nitriles with amines.The method can lead to rich D-A type aggregation-induced emission luminogens(AIEgens)with tunable properties.They emit from deep-blue to yellow-green and possess high photoluminescence quantum yields up to 70.5%in the aggregate state.Interestingly,the suppression of intramolecular flapping is proved to play an indispensable role in the AIE behavior,which is different from the mechanism met in other AIEgens.Moreover,the biocompatible AIEgens possess specific staining of lipid droplets in HeLa cells and the superiority of identifying fatty liver over traditional Oil Red O staining is exhibited. 展开更多
关键词 aggregation-induced emission BIOIMAGING donor-acceptor structure nucleophilic aromatic substitution
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Effect of Co substitution for Fe on microstructure and magnetic properties of FeNiSiBCuNb alloy ribbons
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作者 Wen-Feng Liu Ya-Ting Yuan +5 位作者 Chang-Jiang Yu Shu-Jie Kang Qian-Ke Zhu Zhe Chen Ke-Wei Zhang Min-Gang Zhang 《Chinese Physics B》 2025年第2期438-446,共9页
This work investigated the microstructure,magnetic properties,and crystallization kinetics of the as-spun and annealed alloy ribbons of(Fe_(40-x)Co_xNi_(40)Si_(6.33)B_(12.66)Cu_1)_(0.97)Nb_(0.03),where x=0,6,7,8,9,pre... This work investigated the microstructure,magnetic properties,and crystallization kinetics of the as-spun and annealed alloy ribbons of(Fe_(40-x)Co_xNi_(40)Si_(6.33)B_(12.66)Cu_1)_(0.97)Nb_(0.03),where x=0,6,7,8,9,prepared using the meltspinning method.The results show that adding a moderate amount of Co can improve the glass forming ability(GFA),the first peak crystallization temperature,and thermal stability of the as-spun alloy ribbons.With x=7,the two-stage crystallization temperature interval△Tx=90 exhibits optimal thermal stability,and the alloy annealed at 673 K for 10 minutes shows the favorable combined magnetic properties,with H_(c)=0.12 A/m,M_(s)=88.7 A·m^(2)/kg,andμ_(e)=13800.The magnetic domain results show that annealing removes numerous pinning points in the magnetic domains of the alloy ribbons,making the domain walls smoother and effectively reducing the pinning effect. 展开更多
关键词 amorphous alloys Co substitution for Fe glass formation ability magnetic properties crystallization kinetics
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Synthesis of Allyl Telechelic Poly(4-acetoxystyrene) via Living Cationic Polymerization and Electrophilic Substitution of Allyltrimethylsilane
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作者 Yu Zhu Shuai Wen +4 位作者 Hui Li Tao Zhuang Lu Li Qiang Liu Shou-Ke Yan 《Chinese Journal of Polymer Science》 2025年第6期1043-1049,I0012,共8页
Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding pro... Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution. 展开更多
关键词 Living cationic polymerization 4-Acetoxystyrene Allyl-telechelic polymer Nucleophilic substitution
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Exploring influence of light rare-earth elements and zirconium co-substitution on physical and photocatalytic behavior of BiFeO_(3)
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作者 Zahra Adineh Ahmad Gholizadeh Sakineh Hosseini 《Journal of Rare Earths》 2025年第12期2654-2663,I0003,共11页
Rare earth metals and transition metals co-substitution have been shown to tailor the physical properties of BiFeO_(3).In this work,a series of Bi_(1-x)RE_(x)Fe_(1-x)Zr_(x)O_(3)(RE=La,Pr,Nd,Sm;x=0.00,0.03,0.06)multife... Rare earth metals and transition metals co-substitution have been shown to tailor the physical properties of BiFeO_(3).In this work,a series of Bi_(1-x)RE_(x)Fe_(1-x)Zr_(x)O_(3)(RE=La,Pr,Nd,Sm;x=0.00,0.03,0.06)multiferroic ferrites was synthesized using the sol-gel method.To gain comprehensive insights into these materials,we employed a range of characterization techniques,including X-ray diffraction,Raman and Fourier transform infrared spectroscopies,field emission scanning electron microscopy,UV-Vis spectroscopy,and a vibrating sample magnetometer.Our analysis reveals a rhombohedral crystal structure(R3c space group)for the synthesized ferrites.Notably,we observe a substantial decrease in the optical band gap as the RE/Zr co-substitution increases.Further investigation into the magnetic properties shows a remarkable transition from antiferromagnetic to ferromagnetic behavior,which we attribute to the disruption of the long-range periodicity of the spin cycloid and 4f-3d orbital interactions.In addition,we tested the photocatalytic performance of the RE/Zr co-substituted BiFeO_(3)nanoparticles for the degradation of methyl orange dye under sunlight.The results are quite impressive,with degradation efficiency reaching up to 100%at 40 min by the Bi_(1-x)RE_(x)Fe_(1-x)Zr_(x)O_(3)(RE=La,Sm).Overall,our study demonstrates the vast potential of Bi_(1-x)RE_(x)Fe_(1-x)Zr_(x)O_(3)ferrites in various fields,including optics,magnetism,water treatment,and environmental preservation. 展开更多
关键词 BiFeO_(3) Sol—gel auto-combustion method substitution effect Light rare earths Photocatalytic activity
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Enhanced Regional Electric Potential Difference of Graphdiyne Through Asymmetric Substitution Strategy Boosts Li^(+)Migration in Composite Polymer Solid‑State Electrolyte
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作者 Chao Jiang Kaihang Wang +2 位作者 Luwei Zhang Chunfang Zhang Ning Wang 《Nano-Micro Letters》 2025年第11期155-174,共20页
Low ionic conductivity is a major obstacle for polymer solid-state electrolytes.In response to this issue,a design concept of enhanced regional electric potential difference(EREPD)is proposed to modulate the interacti... Low ionic conductivity is a major obstacle for polymer solid-state electrolytes.In response to this issue,a design concept of enhanced regional electric potential difference(EREPD)is proposed to modulate the interaction of nanofillers with other components in the composite polymer solid-state electrolytes(CPSEs).While ensuring the periodic structure of the graphdiyne(GDY)backbone,methoxysubstituted GDY(OGDY)is prepared by an asymmetric substitution strategy,which increases the electric potential differences within each repeating unit of GDY.The staggered distributed electron-rich regions and electron-deficient regions on the two-dimensional plane of OGDY increase the free Li^(+)concentration through Lewis acid-base pair interaction.The adjacent ERRs and EDRs form uniformly distributed EREPDs,creating a continuous potential gradient that synergistically facilitates the efficient migration of Li^(+).Impressively,the OGDY/poly(ethylene oxide)(PEO)exhibits a high ionic conductivity(1.1×10^(-3)S cm^(−1))and ion mobility number(0.71).In addition,the accelerated Li^(+)migration promotes the formation of uniform and dense SEI layers and inhibits the growth of lithium dendrites.As a proof of concept,Li||Li symmetric cell and Li||LiFePO_(4)full cell and pouch cell assembled with OGDY/PEO exhibit good performance,highlighting the effectiveness of our EREPD design strategy for improving CPSEs performance. 展开更多
关键词 Graphdiyne Asymmetric substitution Enhanced regional electric potential difference Solid-state electrolytes Poly(ethylene oxide)
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Balancing tradition and conservation:Exploring plant part substitution in traditional medicine
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作者 Bhavana Srivastava Himanshu Sharma +1 位作者 Ajay Kumar Meena Vandana Bharthi 《Journal of Integrative Medicine》 2025年第3期209-217,共9页
Traditional medicine,deeply rooted in cultural practices and historical wisdom,has faced surging challenges due to the escalating demand for plant-based remedies.This comprehensive review critically emphasizes the urg... Traditional medicine,deeply rooted in cultural practices and historical wisdom,has faced surging challenges due to the escalating demand for plant-based remedies.This comprehensive review critically emphasizes the urgent need for sustainable practices within traditional medicine,with a special focus on the potential of plant part substitution.Case studies that illuminate successful instances of substituting plant parts and providing a deep insight into viable alternatives to conventional practices are presented.Opportunities and challenges inherent in plant part substitution are discussed by addressing key considerations such as phytochemical and pharmacological aspects,safety and toxicity profiles,cultural insights,standardization,clinical validation,and regulatory compliance.This review serves as a guide for navigating the delicate balance between tradition and conservation within indigenous medicine practices.It underscores the importance of embracing sustainable approaches through plant part substitution,ensuring the preservation of cultural heritage while meeting the evolving healthcare needs of society. 展开更多
关键词 Traditional medicine Plant part substitution Medicinal plants Natural resources conservation
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Suppressing Exciton–Vibration Coupling and Reducing Nonradiative Energy Loss in Conjugated Polymers Through Fluorine Substitution in Side Chains
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作者 Zezhou Liang Lihe Yan +5 位作者 Xiaoming Li Yufei Wang Baofeng Zhao Chao Gao Jinhai Si Hou Xun 《Energy & Environmental Materials》 2025年第3期264-273,共10页
Fluorine(F)substitution in polymers modulates both molecular energy levels and film morphology;however,its impact on exciton–vibrational coupling and molecular reorganization energy is often neglected.Herein,we syste... Fluorine(F)substitution in polymers modulates both molecular energy levels and film morphology;however,its impact on exciton–vibrational coupling and molecular reorganization energy is often neglected.Herein,we systematically investigated F-modified polymers(PBTA-PSF,PBDB-PSF)and their nonfluorinated counterparts(PBTA-PS,PBDB-PS)through simulations and experiments.We found that F atoms effectively lower the vibrational frequency of the molecular skeleton and suppress exciton–vibration coupling,thereby reducing the nonradiative decay rate.Moreover,introducing F atoms significantly decreases the reorganization energy for the S_(0)→S_(1) and S_(0)→cation transitions while increasing the reorganization energy for the S_(1)→S_(0) and cation→S_(0) transitions.These changes facilitate exciton dissociation and reduce the energy loss caused by dissociation and nonradiative recombination of excitons.Additionally,introducing F atoms into polymers enhances theπ–πstacking strength and the crystal coherence length in both neat and blended films,ultimately resulting in improvements in the power conversion efficiency of PBTA-PSF:L8-BO and PBDB-PSF:L8-BO are 16.51%and 17.59%,respectively.This study provides valuable insights for designing organic semiconductor materials to minimize energy loss and achieve a higher power conversion efficiency. 展开更多
关键词 exciton-vibration coupling fluorine substitution nonradiative decay rate reorganization energy
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Aliovalent sulfur-substitution regulated highly amorphous Li_(2)ZrCl_(6) solid electrolytes for all-solid-state lithium metal batteries
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作者 Jin Hu Biao Chen +5 位作者 Chunsheng Shi Liying Ma Junwei Sha Zhonghui Gao Naiqin Zhao Chunnian He 《Journal of Energy Chemistry》 2025年第12期67-78,I0004,共13页
Halide solid-state electrolytes(SSEs)with high ionic conductivity and excellent compatibility with highvoltage oxide cathodes in all-solid-state lithium batteries(ASSLBs)offer improved safety and cycling performance.H... Halide solid-state electrolytes(SSEs)with high ionic conductivity and excellent compatibility with highvoltage oxide cathodes in all-solid-state lithium batteries(ASSLBs)offer improved safety and cycling performance.However,the ionic conductivity of halide SSEs at room temperature(RT)and their stability against lithium(Li)metal anodes still require further enhancement.In this study,Li_(2+x)ZrCl_(6-x)S_(x)(0≤x≤1)SSEs,featuring two highly amorphous phases,are synthesized via an aliovalent sulfursubstitution strategy.Notably,a new phase(C2/m),distinct from Li_(2)ZrCl_(6)(LZC)(p3m1),is induced by modulating the sulfur substitution level for chlorine.Consequently,the crystallinity of the coexisting two-phase SSEs is significantly lower than that of the single-phase material.Owing to their highly amorphous nature,the ionic conductivity of Li_(2.25)ZrCl_(5.75)S_(0.25)(LZCS0.25)increases from 0.33 mS cm^(-1)(LZC)to0.97 mS cm^(-1)at RT.In addition,LZCS0.25 exhibits higher compressibility and lower reduction potential(1.78 V vs.2.34 V for LZC),and the Li/LZCS0.25/Li symmetric cell exhibits improved cycling stability.ASSLBs employing LZCS0.25 and LiCoO_(2) or single-crystal LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) demonstrate high reversible specific capacity and excellent long-term cycling stability.This strategy for regulating the amorphous structure provides valuable guidance for the development of high-performance SSEs for ASSLBs. 展开更多
关键词 Li_(2)ZrCl_(6) Solid-state electrolytes Aliovalent substitution Highly amorphous All-solid-state battery
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