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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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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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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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例析换元法在解题中的应用
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作者 向东 《中学生数理化(高一数学)》 2026年第1期9-10,共2页
一、求函数的解析式例1已知f(l-sin x)-cos^(2)x,则f(x)=__。解析:设1-sinx=t,t∈[0,2],则sin x=1-t。因为f(l-sinx)=cos^(2)x=1-sin^(2)x,所以f(t)=l-(1-t)^(2)=2t-t^(2),t∈[0,2],即函数f(x)=2x-x^(2),x∈[0,2]。
关键词 function analysis substitution method
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Effects of molecular conformation on buried interface passivation and efficient perovskite solar cell realization employing fluorine substituted benzoic acid
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作者 Boyan Li Rongbo Wang +8 位作者 Ya Wang Wentao Wu Weitao Yan Handong Zhang Xingyuan Zhong Juntao Zhao Liyi Yao Wei-Hua Wang Yi Ding 《Journal of Energy Chemistry》 2026年第1期826-831,I0018,共7页
Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of ... Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of fluorine atom influences the passivation effect and para-fluorinated one provided the most substantial performance enhancement mainly originating from ameliorated contact and energy band alignment between NiOx and perovskite,improved perovskite quality and defect healing.Resultantly,PSC with a power conversion efficiency of 24%can be achieved.Meanwhile,which can maintain 96.8%of the initial PCE after a 1000 h storage,presenting enhanced durability.This work highlights the critical role of molecular functionality and conformation in the buried interface modification of PSCs,providing valuable insights for future developments. 展开更多
关键词 Perovskite solar cells F atom substituted benzoic acids Buried interface modification
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Medical Image Encryption Based on Fisher-Yates Scrambling and Filter Diffusion 被引量:1
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作者 HUANG Jiacin GUO Yali +1 位作者 GAO Ruoyun LI Shanshan 《Journal of Shanghai Jiaotong university(Science)》 2025年第1期136-152,共17页
A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,whic... A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research. 展开更多
关键词 medical image encryption Fisher-Yates scrambling three-dimensional filter diffusion bidirectional diffusion S-box substitution
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Breath inspired multifunctional low-cost inorganic colloidal electrolyte for stable zinc metal anode 被引量:1
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作者 Mengyu Rong Yifu Zhang +4 位作者 Xianfang Tan Yang Wang Na Gao Chi Huang Changgong Meng 《Journal of Energy Chemistry》 2025年第3期218-229,共12页
The practical application of aqueous zinc-ion batteries(AZIBs)is primarily constrained by issues such as corrosion,zinc dendrite formation,and the hydrogen evolution reaction occurring at the zinc metal anode.To overc... The practical application of aqueous zinc-ion batteries(AZIBs)is primarily constrained by issues such as corrosion,zinc dendrite formation,and the hydrogen evolution reaction occurring at the zinc metal anode.To overcome these challenges,strategies for optimizing the electrolyte are crucial for enhancing the stability of the zinc anode.Inspired by the role of hemoglobin in blood cells,which facilitates oxygen transport during human respiration,an innovative inorganic colloidal electrolyte has been developed:calcium silicate-ZnSO_(4)(denoted as CS-ZSO).This electrolyte operates in weak acidic environment and releases calcium ions,which participate in homotopic substitution with zinc ions,while the solvation environment of hydrated zinc ions in the electrolyte is regulated.The reduced energy barrier for the transfer of zinc ions and the energy barrier for the desolvation of hydrated ions imply faster ion transfer kinetics and accelerated desolvation processes,thus favoring the mass transfer process.Furthermore,the silicate colloidal particles act as lubricants,improving the transfer of zinc ions.Together,these factors contribute to the more uniform concentration of zinc ions at the electrode/electrolyte interface,effectively inhibiting zinc dendrite formation and reducing by-product accumulation.The Zn//CS-ZSO//Zn symmetric cell demonstrates stable operation for over 5000 h at 1 mA cm^(-2),representing 29-fold improvement compared to the Zn//ZSO//Zn symmetric cell,which lasts only 170 h.Additionally,the Zn//CS-ZSO//Cu asymmetric cell shows stable average Coulombic efficiency(CE)exceeding 99.6%over2400 cycles,significantly surpassing the performance of the ZSO electrolyte.This modification strategy for electrolytes not only addresses key limitations associated with zinc anodes but also provides valuable insights into stabilizing anodes for the advancement of high-performance aqueous zinc-ion energy storage systems. 展开更多
关键词 Inorganic colloidal electrolyte Calcium silicate lonhomotopic substitution Dendrite-free Zn anodes Aqueous zinc-ion battery
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Stabilizing the solid-solution sodium storage in Cr-substituted Na_(3)V_(2)(PO_(4))_(3) cathode for aqueous sodium-ion batteries with long-term stability 被引量:1
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作者 Qinyan Jian Tinghong Gao +4 位作者 Wensheng Yang Xinhai Wang Lishan He Jiarui Liu Yunjun Ruan 《Journal of Energy Chemistry》 2025年第6期797-805,I0016,共10页
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ... Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries. 展开更多
关键词 Na_(3)V_(2)(PO_(4))_(3) Cr substitution Insertion/extraction mechanism Long-term cycling stability Aqueous sodium-ion battery
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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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Transition Metal-Catalyzed Asymmetric Migratory Allylic C—H Functionalization of Remote Dienes
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作者 Jingming Zhang Zhitao He 《有机化学》 北大核心 2025年第2期592-601,共10页
Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution o... Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution of remote dienes has emerged as a new route to achieve allylic C—H functionalization enantioselectively. This review provides a detailed summary of the development and advance of this strategy, introduces the related mechanistic processes, and discusses the area based on the types of catalysts and products. 展开更多
关键词 remote dienes metal walking migratory allylic substitution allylic C-H bond functionalization asymmetric synthesis
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Study on Gold Self-Relay Catalytic Annulation/Nucleophilic Substitu-tion of 1,3-Enyne Acetates with Cyclic Ether Acetals
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作者 Zhang Congyu Chen Xiaoqi +3 位作者 Meng Fantao Wang Haiying Hao Wen-Juan Jiang Bo 《有机化学》 北大核心 2025年第6期2199-2207,共9页
A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones w... A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones with cyclic quaternary centers in moderate to good yields and>19∶1 dr.This catalysis enables the direct construction of two types of carboncyclic skeletons by adjusting the olefin types of 1,3-enyne acetates.When 1,3-enyne acetates bearing a cyclic alkene unit were used,5~6 fused bicarbocyclic products were diastereoselectively synthesized,whereas the reaction of acyclic 1,3-enyne acetates resulted in five-memebered carbocyclic framework.Notably,cyclic ether acetals are commonly used as protecting groups in traditional multistep organic syntheses,and in this reaction,such reagents serve as electrophilic cyclic ether precursors,achieving new uses for old reagents.The current method demonstrates good functional group compatibility,a broad substrate scope and high diastereoselectivity,providing a new synthetic strategy toward functionalized cyclopentenones. 展开更多
关键词 gold self-relay catalysis Nazarov cyclization nucleophilic substitution 1 3-enyne acetates cyclic ether acetals
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Effect of Ga^(3+) Doping on Crystal Structure Evolution and Microwave Dielectric Properties of SrAl_(2)O_(8) Ceramic
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作者 YIN Changzhi CHENG Mingfei +5 位作者 LEI Weicheng CAI Yiyang SONG Xiaoqiang FU Ming LÜWenzhong LEI Wen 《无机材料学报》 北大核心 2025年第6期704-710,共7页
The feldspar-based microwave dielectric ceramic with low relative permittivity(εr)and excellent mechanical properties has attracted much attention in the fifth-generation wireless communication technology.In this wor... The feldspar-based microwave dielectric ceramic with low relative permittivity(εr)and excellent mechanical properties has attracted much attention in the fifth-generation wireless communication technology.In this work,a series of microwave dielectric ceramic SrAl_(2-x)Ga_(x)Si_(2)O_(8)(0.1≤x≤2.0)was synthesized using the traditional solid-state method.X-ray diffraction pattern indicates that Ga^(3+)can be dissolved into Al^(3+),forming a solid solution.Meanwhile,substitution of Ga^(3+)for Al^(3+)can promote the space group transition from I2/c(0.1≤x≤1.4)to P21/a(1.6≤x≤2.0)with coefficient of thermal expansion(CTE)increasing from 2.9×10^(-6)℃^(-1) to 5.2×10^(-6)℃^(-1).During this substitution,the phase transition can significantly improve the structural symmetry to enhance the dielectric properties and mechanical properties.Rietveld refinement results indicate that Ga^(3+)averagely occupied four Al^(3+)compositions to form solid solution.All ceramics have a dense microstructure and high relative density above 95%.An ultralower of 5.8 was obtained at x=1.6 composition with high quality factor(Q´f)of 50700 GHz and negative temperature coefficients of resonant frequency(tf)of approximately−35×10^(-6)℃^(-1).The densification temperature can be reduced to 940℃by adding 4%(in mass)LiF,resulting in good chemical compatibility with Ag electrode.Meanwhile,negativetf can be tuned to near-zero(+3.7×10^(-6)℃^(-1))by adding CaTiO_(3) ceramic. 展开更多
关键词 ion substitution microwave dielectric ceramic dielectric property low-temperature co-fired ceramic
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Recovery of Industrial Waste: Paving Stones Made from Hardened Cement Base
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作者 Serifou Mamery Adama Konin Athanas Augou Ovo Sandrine Flora 《Journal of Materials Science and Chemical Engineering》 2025年第2期68-82,共15页
Industrial waste management constitutes a major challenge for sustainable development. This study aims to transform hardened cement waste stored in cement warehouses and in real estate construction sites into paving s... Industrial waste management constitutes a major challenge for sustainable development. This study aims to transform hardened cement waste stored in cement warehouses and in real estate construction sites into paving stones. This innovative solution will contribute to the protection of the environment and the reduction of inert industrial waste. To do this, paving stones based on hardened cement have been developed and characterized. The raw materials were subjected to physical and mechanical characterization tests. The hardened cement aggregates previously crushed with the 5/15 granular class were used as substitutes to replace the natural 5/15 aggregates in the hardened paving stones at contents ranging from 0 to 100%. The mechanical characterization results on the raw material showed that the hardened cement aggregate is made from lightweight aggregates. On the prepared mortar, in the fresh state, the Abrams cone slump test showed an increase in the quantity of waste water with the increase in the content of hardened cement aggregate. In the hardened state, physical (porosity, absorption and dry density) and mechanical (compression, splitting traction, 3-point bending traction and wear) characterization tests were carried out at periods of 7, 14 and 28 days of maturation in water on the cobblestones. These results show that the substitution of natural aggregates by hardened cement aggregates in increasingly large proportions leads to an improvement in compressive, flexural, splitting and wear resistance. In addition, the incorporation of hardened cement aggregate considerably slows down the mechanical degradation of the paving stones. They can, therefore, be used in road and interior or exterior floor coverings. 展开更多
关键词 Paving Stones Hardened Cement INNOVATIVE Waste RECOVERY SUBSTITUTION
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Bioengineered skin-substitutes incorporating rete-ridges using a bioprinting process
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作者 SooJung Chae SeoYul Jo +7 位作者 Dogeon Yoon Ji-Seon Lee WonJin Kim JaeYoon Lee Ji-Hye Park You-rin Kim Wook Chun GeunHyung Kim 《International Journal of Extreme Manufacturing》 2025年第1期522-541,共20页
Bioprinting is a widely used technique for creating three-dimensional,complex,and heterogeneous artificial tissue constructs that are biologically and biophysically similar to natural tissues.The skin is composed of s... Bioprinting is a widely used technique for creating three-dimensional,complex,and heterogeneous artificial tissue constructs that are biologically and biophysically similar to natural tissues.The skin is composed of several layers including the epidermis,basement membrane(BM),and dermis.However,the unique undulating structure of basement membranes(i.e.rete ridges)and the function of BM have not been extensively studied in the fabrication of engineered skin substitutes.In this study,a novel engineered skin substitute incorporating an artificially designed rete ridge(i.e.mogul-shape)was developed using bioprinting and bioinks prepared using collagen and fibrinogen.To mimic the structure of the rete ridges of skin tissue,we developed a modified bioprinting technique,controlling rheological property of bioink to create a mogul-shaped layer.In vitro cellular activities,including the expression of specific genes(those encoding vimentin,laminin-5,collagen IV,and cytokeratins),demonstrated that the engineered skin substitute exhibited more potent cellular responses than the normally bioprinted control owing to the favorable biophysical BM structure and the bioink microenvironment.Additionally,the feasibility of utilizing the bioprinted skin-structure was evaluated in a mouse model,and in vivo results demonstrated that the bioprinted skin substitutes effectively promoted wound healing capabilities.Based on these results,we suggest that bioprinted skin tissues and the bioprinting technique for mimicking rete ridges can be used not only as potential lab-chip models for testing cosmetic materials and drugs,but also as complex physiological models for understanding human skin. 展开更多
关键词 collagen FIBRINOGEN basement membrane skin substitute BIOPRINTING
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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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Enhanced electronic and photoelectrical properties of two-dimensional Zn-doped SnS_(2)
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作者 Xichen Chuai Peng Yin +7 位作者 Jiawei Wang Guanhua Yang Congyan Lu Di Geng Ling Li Can Liu Zhongming Wei Nianduan Lu 《Chinese Physics B》 2025年第5期491-496,共6页
Alloy engineering,with its ability to tune the electronic band structure,is regarded as an effective method for adjusting the electronic and optoelectronic properties of two-dimensional(2D)semiconductors.However,synth... Alloy engineering,with its ability to tune the electronic band structure,is regarded as an effective method for adjusting the electronic and optoelectronic properties of two-dimensional(2D)semiconductors.However,synthesizing metal-site substitution alloys remains challenging due to the low reactivity of metal precursors and the tendency for spatial phase separation during high-temperature growth.Here,we report the preparation of a high-quality metal-site substitution alloy,Zn_(0.167)Sn_(0.833)S_(2),via the chemical vapor transport method,which exhibits excellent photoresponsivity and enhanced electrical transport properties.Comprehensive characterization techniques,including Raman spectroscopy,x-ray photoelectron spectroscopy(XPS),and electron microscopy,unambiguously confirm the uniform Zn substitution in the as-prepared Zn_(0.167)Sn_(0.833)S_(2) alloy.Furthermore,the photodetector based on the Zn_(0.167)Sn_(0.833)S_(2) alloy demonstrated a high on/off ratio of 51 under white light,a wide spectral response range from 350 nm to 900 nm,and a broad dynamic power range of 80 dB under 638-nm illumination.In terms of transport properties,field-effect transistors(FETs)based on Zn_(0.167)Sn_(0.833)S_(2) achieved a carrier mobility of 6.5 cm^(2)·V^(-1)·s^(-1),which is six times higher than that of SnS_(2).This alloy semiconductor showcases significantly enhanced electronic and optoelectronic properties,offering great potential for the development of high-resolution photodetection technologies. 展开更多
关键词 alloy engineering metal-site substitution PHOTODETECTOR field-effect transistors
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Deep fluorination-driven fast-charge and high-capacity sodium oxide cathode
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作者 Guomin Li Lei Lei +5 位作者 Yanyi Wang Hongwei Mi Chuanxin He Ning Zhao Peixin Zhang Dingtao Ma 《Journal of Energy Chemistry》 2025年第10期941-951,共11页
To advance the application of layered oxide cathodes in fast-charging sodium-ion batteries,it is crucial to not only suppress irreversible phase transitions but also improve the rate capability of cathode materials an... To advance the application of layered oxide cathodes in fast-charging sodium-ion batteries,it is crucial to not only suppress irreversible phase transitions but also improve the rate capability of cathode materials and optimize Na^(+)diffusion kinetics to ensure high capacity output at various charge-discharge rates.In this research,the targeted F-substitution with a heavy ratio in oxygen anion layer optimizes the Na^(+)diffusion path and electronic conductivity of the material,thereby decreasing the Na^(+)diffusion barrier and imparting high-rate performance.At a 20 C rate,the cathode achieves a capacity of over 80 mAh g^(-1)with stable cycling performance.Additionally,the dual rivet effect between the transition metal layer and oxygen layer prevents significant phase transitions during charge/discharge within the 2-4.2 V range for the modified cathode.As a result,the F-substituted oxygen anion layer improved Na^(+)diffusion,electronic conductivity,and crystal plane structure stability,which led to the development of a highperformance,fast-charging sodium-ion battery(SIB),opening new avenues for commercial applications. 展开更多
关键词 Sodium-ion batteries Layered cathode materials Fluorine substitution Fast-charging Diffusion barrier
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GL6.1 integrates grain length regulation and disease resistance via OsWRKY53-mediated signaling in rice
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作者 Hongyuan Zhao Yu Fu +13 位作者 Yingqin Luo Weifeng Yang Yanhao Gao Xiaoya Liang Ying Zhang Deshu Zhao Shiquan Li Fangping Li Guodong Chen Penglin Zhan Zupei Liu Suhong Bu Guiquan Zhang Shaokui Wang 《The Crop Journal》 2025年第5期1451-1459,共9页
Grain size is a crucial factor influencing both rice yield and appearance quality.In this study,we identified GL6.1 as a gene associated with rice grain size by map-based cloning.The GL6.1 encodes a protein with CC-NB... Grain size is a crucial factor influencing both rice yield and appearance quality.In this study,we identified GL6.1 as a gene associated with rice grain size by map-based cloning.The GL6.1 encodes a protein with CC-NB-LRR domain,a structural motif related to rice disease resistance.Genetic transformation experiments and the construction of gene pyramiding lines indicate that GL6.1 functions as a negative regulatory factor for rice grain length.By the analysis of SSSLs with diverse donor parents,a total of 11 single nucleotide polymorphisms(SNPs)are identified that are closely associated with the phenotype variations.A yeast one-hybrid library screening revealed that GL6.1 interacts with OsWRKY53,a transcription factor associated with rice disease resistance.Furthermore,RNA-seq assay also revealed the involvement of pathways associated with disease resistance,hinting at a multifaceted role for GL6.1 in both yield and stress tolerance traits in rice.These results indicate that the cloning and in-depth studies of GL6.1 would provide valuable insights into the interplay among high yield,superior quality,and stress tolerance,which are critical goals for rice breeding. 展开更多
关键词 RICE GL6.1 Grain length Disease resistance Single-segment substitution line
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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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