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Nitrogen‑Doped Magnetic‑Dielectric‑Carbon Aerogel for High‑Efficiency Electromagnetic Wave Absorption 被引量:2
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作者 Shijie Wang Xue Zhang +5 位作者 Shuyan Hao Jing Qiao Zhou Wang Lili Wu Jiurong Liu Fenglong Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期313-327,共15页
Carbonbased aerogels derived from biomass chitosan are encountering a flourishing moment in electromagnetic protection on account of lightweight,controllable fabrication and versatility.Nevertheless,developing a facil... Carbonbased aerogels derived from biomass chitosan are encountering a flourishing moment in electromagnetic protection on account of lightweight,controllable fabrication and versatility.Nevertheless,developing a facile construction method of component design with carbon-based aerogels for high-efficiency electromagnetic wave absorption(EWA)materials with a broad effective absorption bandwidth(EAB)and strong absorption yet hits some snags.Herein,the nitrogen-doped magnetic-dielectric-carbon aerogel was obtained via ice template method followed by carbonization treatment,homogeneous and abundant nickel(Ni)and manganese oxide(MnO)particles in situ grew on the carbon aerogels.Thanks to the optimization of impedance matching of dielectric/magnetic components to carbon aerogels,the nitrogen-doped magnetic-dielectric-carbon aerogel(Ni/MnO-CA)suggests a praiseworthy EWA performance,with an ultra-wide EAB of 7.36 GHz and a minimum reflection loss(RLmin)of−64.09 dB,while achieving a specific reflection loss of−253.32 dB mm−1.Furthermore,the aerogel reveals excellent radar stealth,infrared stealth,and thermal management capabilities.Hence,the high-performance,easy fabricated and multifunctional nickel/manganese oxide/carbon aerogels have broad application aspects for electromagnetic protection,electronic devices and aerospace. 展开更多
关键词 Electromagnetic wave absorption Wide bandwidth Dielectric-magnetic synergy MULTIFUNCTION
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High performance wide bandgap perovskite solar cell with low V_(OC) deficit less than 0.4 V 被引量:1
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作者 Haikuo Guo Fuhua Hou +8 位作者 Xuli Ning Xiaoqi Ren Haoran Yang Rui Liu Tiantian Li Chengjun Zhu Ying Zhao Wei Li Xiaodan Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期313-322,共10页
Wide bandgap perovskite solar cells(PSCs)have attracted significant attention because they can be applied to the top cells of tandem solar cells.However,high open-circuit voltage(V_(OC))deficit(>0.4 V)result from p... Wide bandgap perovskite solar cells(PSCs)have attracted significant attention because they can be applied to the top cells of tandem solar cells.However,high open-circuit voltage(V_(OC))deficit(>0.4 V)result from poor crystallization and high non-radiative recombination losses become a serious limitation in the pursuit of high performance.Here,the relevance between different Pbl_(2)proportions and performance parameters are revealed through analysis of surface morphology,residual stress,and photostability.The increase of Pbl_(2)proportion promotes crystal growth and reduces the work function of the perovskite film surface and promotes the energy level alignment with the carrier transport layer,which decreased the V_(OC)deficit.However,residual PbI_(2)exacerbated the stress level of perovskite film,and the resulting lattice disorder deteriorated the photostability of the device.Ultimately,after the synergistic passivation of residual PbI_(2)and PEAI,the V_(OC)achieves 1.266 V and V_(OC)deficit is less than 0.4 V,the record value in wide bandgap PSCs. 展开更多
关键词 Pb management Perovskite solar cell STRAIN Wide bandgap Stability
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Identification of SSR markers linked to the abscission of cotton boll traits and mining germplasm in Cotton 被引量:1
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作者 SHUI Guangling LIN Hairong +9 位作者 MA Xiaomei ZHU Bo HAN Peng AINI Nurimanguli GUO Chunping WU Yuanlong PAN Zhenyuan YOU Chunyuan SONG Guoli NIE Xinhui 《Journal of Cotton Research》 CAS 2024年第2期177-187,共11页
Background Cotton is an economically important crop.It is crucial to find an effective method to improve cotton yield,and one approach is to decrease the abscission of cotton bolls and buds.However,the lack of knowled... Background Cotton is an economically important crop.It is crucial to find an effective method to improve cotton yield,and one approach is to decrease the abscission of cotton bolls and buds.However,the lack of knowledge of the genetic and molecular mechanisms underlying cotton boll abscission traits has hindered genetic improvements.Results Pearson’s correlation analysis revealed a significant positive correlation between boll abscission rates 1(AR1)and boll abscission rates 2(AR2).A genome-wide association study was conducted on 145 loci that exhibited high polymorphism and were uniformly distributed across 26 chromosomes(pair).The study revealed 18,46,and 62 markers that were significantly associated with boll abscission,fiber quality,and yield traits(P<0.05),explaining 1.75%–7.13%,1.16%–9.58%,and 1.40%–5.44%of the phenotypic variation,respectively.Notably,the marker MON_SHIN-1584b was associated with the cotton boll abscission trait,whereas MON_CGR5732a was associated with cotton boll abscission and fiber quality traits.Thirteen of the marker loci identified in this study had been previously reported.Based on phenotypic effects,six typical cultivars with elite alleles related to cotton boll abscission,fiber quality,and yield traits were identified.These cultivars hold great promise for widespread utilization in breeding programs.Conclusions These results lay the foundation for understanding the molecular regulatory mechanism of cotton boll abscission and provide data for the future improvement of cotton breeding. 展开更多
关键词 SSR Genome wide association studies ABSCISSION Favorable alleles COTTON Genetic improvement
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Bimetallic In_(2)O_(3)/Bi_(2)O_(3) Catalysts Enable Highly Selective CO_(2) Electroreduction to Formate within Ultra-Broad Potential Windows 被引量:1
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作者 Zhongxue Yang Hongzhi Wang +7 位作者 Xinze Bi Xiaojie Tan Yuezhu Zhao Wenhang Wang Yecheng Zou Huai ping Wang Hui Ning Mingbo Wu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期257-264,共8页
CO_(2)electrochemical reduction reaction(CO_(2)RR)to formate is a hopeful pathway for reducing CO_(2)and producing high-value chemicals,which needs highly selective catalysts with ultra-broad potential windows to meet... CO_(2)electrochemical reduction reaction(CO_(2)RR)to formate is a hopeful pathway for reducing CO_(2)and producing high-value chemicals,which needs highly selective catalysts with ultra-broad potential windows to meet the industrial demands.Herein,the nanorod-like bimetallic ln_(2)O_(3)/Bi_(2)O_(3)catalysts were successfully synthesized by pyrolysis of bimetallic InBi-MOF precursors.The abundant oxygen vacancies generated from the lattice mismatch of Bi_(2)O_(3)and ln_(2)O_(3)reduced the activation energy of CO_(2)to*CO_(2)·^(-)and improved the selectivity of*CO_(2)·^(-)to formate simultaneously.Meanwhile,the carbon skeleton derived from the pyrolysis of organic framework of InBi-MOF provided a conductive network to accelerate the electrons transmission.The catalyst exhibited an ultra-broad applied potential window of 1200 mV(from-0.4 to-1.6 V vs RHE),relativistic high Faradaic efficiency of formate(99.92%)and satisfactory stability after 30 h.The in situ FT-IR experiment and DFT calculation verified that the abundant oxygen vacancies on the surface of catalysts can easily absorb CO_(2)molecules,and oxygen vacancy path is dominant pathway.This work provides a convenient method to construct high-performance bimetallic catalysts for the industrial application of CO_(2)RR. 展开更多
关键词 bimetallic catalyst CO_(2)electrochemical reduction reaction FORMATE oxygen vacancy wide potential window
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Design strategies and recent advancements of solid-state supercapacitor operating in wide temperature range
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作者 Jie Zhou Zhengfeng Zhu +4 位作者 Wenhui Shi Xiangyu Shi Zhuoyuan Zheng Ye Xiong Yusong Zhu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期248-281,共34页
Solid-state supercapacitors(SSCs)are emerging as one of the promising energy storage devices due to their high safety,superior power density,and excellent cycling life.However,performance degradation and safety issues... Solid-state supercapacitors(SSCs)are emerging as one of the promising energy storage devices due to their high safety,superior power density,and excellent cycling life.However,performance degradation and safety issues under extreme conditions are the main challenges for the practical application.With the expansion of human activities,such as space missions,polar exploration,and so on,the investigation of SSC with wide temperature tolerance,high energy density,power density,and sustainability is highly desired.In this review,the effects of temperature on SSC are systematically illustrated and clarified,including the properties of the electrolyte,ion diffusion,and reaction dynamics of the supercapacitor.Subsequently,we summarize the recent advances in wide-temperature-range SSCs from the aspect of electrolyte modification,electrode design,and interface adjustment between electrode and electrolyte,especially with critical concerns on ionic conductivity and cycling stability.In the end,a perspective is presented,expecting to promote the practical application of the SSC in harsh conditions. 展开更多
关键词 ELECTRODE INTERFACE solid-state electrolyte solid-state supercapacitor wide temperature
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The role of the auxin-response genes MdGH3.1 and MdSAUR36 in bitter pit formation in apple
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作者 Daqing Huang Wen Peng +3 位作者 Na Gong Lina Qiu Yongzhang Wang Haiyong Qu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1085-1098,共14页
Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome anal... Apples often exhibit bitter pits in response to metabolic disorders during ripening and storage;however, the mechanisms underlying the bitter pit(BP) development remain unclear. Here, metabolome and transcriptome analyses were performed to investigate BP pulp of 'Fuji'. Two auxin-response genes, MdGH3.1 and MdSAUR36, were screened. Their expression as well as the auxin content in BP pulp were found to be higher than those in healthy pulp(P < 0.01). In the field, excess CO(NH2)2increased the incidence of BP. Moreover, the auxin content and MdGH3.1 expression increased in apples after nitrogen fertilization. On Day 30 before harvest, the two genes were transiently transferred to the fruit, and 20.69% and 23.21% of BP fruits were harvested. After 10 μmol·L-1auxin was infiltrated at low pressure into postharvest fruit, the increase in MdGH3.1 expression occurred earlier than that in MdSAUR36. MdGH3.1 increased the expression of MdSAUR36, but MdSAUR36 did not increase expression of MdGH3.1. Therefore, we suggest that MdGH3.1 acts upstream of MdSAUR36 during BP formation and that these genes induce BP formation by regulating auxin and phenylpropanoid biosynthesis. 展开更多
关键词 APPLE Malusdomestica AUXIN Bitter pit FLAVONOIDS Nitrogen fertilizer Widely targeted metabolomics
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Regulating interfacial chemistry and kinetic behaviors of F/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°C-60°C
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作者 Siqi Guan Lin Tao +9 位作者 Pei Tang Ruopian Fang Huize Wu Nan Piao Huicong Yang Guangjian Hu Xin Geng Lixiang Li Baigang An Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期449-457,共9页
Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature condit... Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°C and above 50 °C).Here,we report the design of F/Mo co-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(FMNCM)cathode for high-performance LIBs from-20 to 60°C.F^(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a LiF-rich surface layer.Concurrently,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion pathway.Remarkably,the FMNCM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°C,maintaining 90.6%capacity retention at 3 C after 150 cycles.Additionally,at temperatures as low as-20°C,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 cycles.Such stable operation under wide temperatures has been further validated in practical Ah-level pouch-cells.This study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability. 展开更多
关键词 Anion-cation co-doping Wide temperature operation Ni-richlayered cathode Phase transition Surface/interface
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Automatic diagnosis of diabetic retinopathy using vision transformer based on wide-field optical coherence tomography angiography
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作者 Zenan Zhou Huanhuan Yu +3 位作者 Jiaqing Zhao Xiangning Wang Qiang Wu Cuixia Dai 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期35-44,共10页
Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with diabetes.Optical coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing DR.Recently,... Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with diabetes.Optical coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing DR.Recently,wide-field OCTA(WF-OCTA)provided more abundant information including that of the peripheral retinal degenerative changes and it can contribute in accurately diagnosing DR.The need for an automatic DR diagnostic system based on WF-OCTA pictures attracts more and more attention due to the large diabetic population and the prevalence of retinopathy cases.In this study,automatic diagnosis of DR using vision transformer was performed using WF-OCTA images(12 mm×12 mm single-scan)centered on the fovea as the dataset.WF-OCTA images were automatically classified into four classes:No DR,mild nonproliferative diabetic retinopathy(NPDR),moderate to severe NPDR,and proliferative diabetic retinopathy(PDR).The proposed method for detecting DR on the test set achieves accuracy of 99.55%,sensitivity of 99.49%,and specificity of 99.57%.The accuracy of the method for DR staging reaches up to 99.20%,which has been proven to be higher than that attained by classical convolutional neural network models.Results show that the automatic diagnosis of DR based on vision transformer and WF-OCTA pictures is more effective for detecting and staging DR. 展开更多
关键词 Wide field optical coherence tomography angiography diabetic retinopathy vision transformer image classification
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Characteristic analysis of 5D symmetric Hamiltonian conservative hyperchaotic system with hidden multiple stability
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作者 黄丽莲 马衍昊 李创 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期303-315,共13页
Conservative chaotic systems have unique advantages over dissipative chaotic systems in the fields of secure communication and pseudo-random number generator because they do not have attractors but possess good traver... Conservative chaotic systems have unique advantages over dissipative chaotic systems in the fields of secure communication and pseudo-random number generator because they do not have attractors but possess good traversal and pseudorandomness. In this work, a novel five-dimensional(5D) Hamiltonian conservative hyperchaotic system is proposed based on the 5D Euler equation. The proposed system can have different types of coordinate transformations and time reversal symmetries. In this work, Hamilton energy and Casimir energy are analyzed firstly, and it is proved that the new system satisfies Hamilton energy conservation and can generate chaos. Then, the complex dynamic characteristics of the system are demonstrated and the conservatism and chaos characteristics of the system are verified through the correlation analysis methods such as phase diagram, equilibrium point, Lyapunov exponent, bifurcation diagram, and SE complexity. In addition, a detailed analysis of the multistable characteristics of the system reveals that many energy-related coexisting orbits exist. Based on the infinite number of center-type and saddle-type equilibrium points, the dynamic characteristics of the hidden multistability of the system are revealed. Then, the National Institute of Standards and Technology(NIST)test of the new system shows that the chaotic sequence generated by the system has strong pseudo-random. Finally, the circuit simulation and hardware circuit experiment of the system are carried out with Multisim simulation software and digital signal processor(DSP) respectively. The experimental results confirm that the new system has good ergodicity and realizability. 展开更多
关键词 Hamilton conservative hyperchaotic system symmetry wide parameter range hide multiple stability
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Design of a high sensitivity and wide range angular rate sensor based on exceptional surface
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作者 丁鑫圣 刘文耀 +7 位作者 王师贤 陶煜 周彦汝 白禹 刘来 邢恩博 唐军 刘俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期277-286,共10页
It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low an... It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low angular rate.However,in fact,the exceptional point is easily disturbed by external environmental variables,which means that it depends on harsh experimental environment and strong control ability,so it is difficult to move towards practical application.Here,we propose a new angular rate sensor structure based on exceptional surface,which has the advantages of high sensitivity and high robustness.The system consists of two fiber-optic ring resonators and two optical loop mirrors,and one of the resonators contains a variable ratio coupler and a variable optical attenuator.We theoretically analyze the system response,and the effects of phase and coupling ratio on the system response.Finally,compared with the conventional resonant gyro,the sensitivity of this exceptional surface angular rate sensor can be improved by about 300 times at low speed.In addition,by changing the loss coefficient in the ring resonator,we can achieve a wide range of 600 rad/s.This scheme provides a new approach for the development of ultra-high sensitivity and wide range angular rate sensors in the future. 展开更多
关键词 exceptional surface exceptional points ring resonator angular rate sensing rotational direction recognition wide operating range
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Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range
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作者 Tingsong Hu Wenyi Lian +4 位作者 Kang Hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期160-175,共16页
Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kine... Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kinetics.Herein,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as cathode.The unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon illumination.The illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 cycles.Even at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT cathode.This work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency. 展开更多
关键词 Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)
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Surface-functionalized hole-selective monolayer for high efficiency single-junction wide-bandgap and monolithic tandem perovskite solar cells
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作者 Devthade Vidyasagar Yeonghun Yun +13 位作者 Jae Yu Cho Hyemin Lee Kyung Won Kim Yong Tae Kim Sung Woong Yang Jina Jung Won Chang Choi Seonu Kim Rajendra Kumar Gunasekaran Seok Beom Kang Kwang Heo Dong Hoe Kim Jaeyeong Heo Sangwook Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期317-326,I0008,共11页
Carbazole moiety-based 2PACz([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)self-assembled monolayers(SAMs)are excellent hole-selective contact(HSC)materials with abilities to excel the charge-transferdynamics of perovski... Carbazole moiety-based 2PACz([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)self-assembled monolayers(SAMs)are excellent hole-selective contact(HSC)materials with abilities to excel the charge-transferdynamics of perovskite solar cells(PSCs).Herein,we report a facile but powerful method to functionalize the surface of 2PACz-SAM,by which reproducible,highly stable,high-efficiency wide-bandgap PSCs can be obtained.The 2PACz surface treatment with various donor number solvents improves assembly of 2PACz-SAM and leave residual surface-bound solvent molecules on 2PACz-SAM,which increases perovskite grain size,retards halide segregation,and accelerates hole extraction.The surface functionalization achieves a high power conversion efficiency(PCE)of 17.62%for a single-junction wide-bandgap(~1.77 e V)PSC.We also demonstrate a monolithic all-perovskite tandem solar cell using surfaceengineered HSC,showing high PCE of 24.66%with large open-circuit voltage of 2.008 V and high fillfactor of 81.45%.Our results suggest this simple approach can further improve the tandem device,when coupled with a high-performance narrow-bandgap sub-cell. 展开更多
关键词 Perovskite solar cells 2PACz Monolithic tandem solar cells Wide bandgap
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Alkyl chain modulation of asymmetric hexacyclic fused acceptor synergistically with wide bandgap third component for high efficiency ternary organic solar cells
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作者 Shufang Li Huilan Guan +4 位作者 Can Zhu Chaoyuan Sun Qingya Wei Jun Yuan Yingping Zou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1713-1719,共7页
Herein,two asymmetric hexacyclic fused small molecule acceptors(SMAs),namely BP4F-HU and BP4F-UU,were synthesized.The elongated outside chains in the BP4F-UU molecule played a crucial role in optimizing the morphology... Herein,two asymmetric hexacyclic fused small molecule acceptors(SMAs),namely BP4F-HU and BP4F-UU,were synthesized.The elongated outside chains in the BP4F-UU molecule played a crucial role in optimizing the morphology of blend film,thereby improving charge mobility and reducing energy loss within the corresponding film.Notably,the PM6:BP4F-UU device exhibited a higher open-circuit voltage(V_(oc))of 0.878 V compared to the PM6:BP4F-HU device with a V_(oc)of 0.863 V.Further,a new wide bandgap SMA named BTP-TA was designed and synthesized as the third component to the PM6:BP4F-UU host binary devices,which showed an ideal complementary absorption spectrum in PM6:BP4F-UU system.In addition,BTP-TA can achieve efficient intermolecular energy transfer to BP4F-UU by fluorescence resonance energy transfer(FRET)pathway,due to the good overlap between the photoluminescence(PL)spectrum of BTP-TA and the absorption region of BP4F-UU.Consequently,ternary devices with 15wt%BTP-TA exhibits broader photon utilization,optimal blend morphology,and reduced charge recombination compared to the corresponding binary devices.Consequently,PM6:BP4F-UU:BTP-TA ternary device achieved an optimal power conversion efficiency(PCE)of 17.83%with simultaneously increased V_(oc)of 0.905 V,short-circuit current density(J_(sc))of 26.14 mA/cm^(2),and fill factor(FF)of 75.38%. 展开更多
关键词 asymmetric hexacyclic acceptor outside chain wide bandgap acceptor ternary organic solar cells
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Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast
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作者 Olga Nabochenko Mykola Sysyn +1 位作者 Norman Krumnow Szabolcs Fischer 《Railway Engineering Science》 EI 2024年第3期361-383,共23页
The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses.However,the mechanism of the irregul... The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses.However,the mechanism of the irregularities initiation and development is unclear.The motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted track.The long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional track.However,wide sleepers had higher twist and cross-section level irregularities.The present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper form.The DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional one.Nevertheless,the cross-level differential settlements are almost the same for both sleepers.The particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper ends.Ballast flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level irregularities.The mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper ends.The further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the sleeper.The DEM simulation results support the assumption of the mechanism and agree with the experimental studies. 展开更多
关键词 Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation
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Electrical structure identification of deep shale gas reservoir in complex structural area using wide field electromagnetic method
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作者 Gu Zhi-Wen Li Yue-Gang +6 位作者 Yu Chang-Heng Zou Zhong-Ping Hu Ai-Guo Yin Xue-Bo Wang Qinag Ye Heng Tan Zhang-Kun 《Applied Geophysics》 SCIE CSCD 2024年第3期564-578,619,620,共17页
To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the con... To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the conventional electromagnetic method in exploration depth,precision,and accuracy,the large-depth and high-precision wide field electromagnetic method is applied to the complex structure test area of the Luochang syncline and Yuhe nose anticline in the southern Sichuan.The advantages of the wide field electromagnetic method in detecting deep,low-resistivity thin layers are demonstrated.First,on the basis of the analysis of physical property data,a geological–geoelectric model is established in the test area,and the wide field electromagnetic method is numerically simulated to analyze and evaluate the response characteristics of deep thin shale gas layers on wide field electromagnetic curves.Second,a wide field electromagnetic test is conducted in the complex structure area of southern Sichuan.After data processing and inversion imaging,apparent resistivity logging data are used for calibration to develop an apparent resistivity interpretation model suitable for the test area.On the basis of the results,the characteristics of the electrical structure change in the shallow longitudinal formation of 6 km are implemented,and the transverse electrical distribution characteristics of the deep shale gas layer are delineated.In the prediction area near the well,the subsequent data verification shows that the apparent resistivity obtained using the inversion of the wide field electromagnetic method is consistent with the trend of apparent resistivity revealed by logging,which proves that this method can effectively identify the weak response characteristics of deep shale gas formations in complex structural areas.This experiment,it is shown shows that the wide field electromagnetic method with a large depth and high precision can effectively characterize the electrical characteristics of deep,low-resistivity thin layers in complex structural areas,and a new set of low-cost evaluation technologies for shale gas target layers based on the wide field electromagnetic method is explored. 展开更多
关键词 complex tectonic area in southern Sichuan wide field electromagnetic method deep exploration shale gas reservoir electrical structure
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4-Hydroxy-2-Oxoglutaric Acid,A KeyMetabolite Involved in Trypsin-Regulation of Arginine Metabolism in Hylocereus undatus during Storage
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作者 Bairu Li Jingyu Jia +3 位作者 Hemin Wang Jiaju Sun Enyan Chen Xin Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期885-900,共16页
Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,a... Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,and transcriptomics analysis were conducted.Firstly,a total of 453 metabolites were identified,with organic acids and their derivatives constituting the largest proportion(25%).Amino acids and their metabolites,prominent among organic acids,were further analyzed.Among them,73 metabolites were associated with amino acids,and 37 exhibited significant differences.The most enriched Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway was arginine biosynthesis(map00220),with polyamine metabolites showing the most pronounced differences,particularly spermine(FC=1.7594).Compared with the control group,4-hydroxy-2-oxoglutaric acid was significantly upregulated(FC=2.117)in the process of spermine biosynthesis.Furthermore,the results of Gene Ontology(GO)and KEGG enrichment analysis of the H.undatus transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine.Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process(GO:0006597)(map:00220)within the arginine biosynthesis pathway.Moreover,most enzymes and metabolites within the spermine biosynthesis pathway in H.undatus were upregulated.The results of the PPI network highlighted that ADC,SPDS,and SAMDC,among others,were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis.This study revealed that trypsin could significantly delay postharvest senescence of H.undatus at room temperature.This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel,thereby promoting the biosynthesis of spermine and other polyamines. 展开更多
关键词 TRYPSIN ARGININE TRANSCRIPTOMICS widely targeted metabolomics
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EuSHT Acts as a Hub Gene Involved in the Biosynthesis of 6-Hydroxyluteolin and Quercetin Induced by Salt Stress in Eucommia ulmoides
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作者 Fuxin Li Enyan Chen +5 位作者 Xinxin Chen Jingyu Jia Hemin Wang Jie Zhang Jianrui Sun Xin Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第8期2095-2113,共19页
Salt stress inhibits plant growth and affects the biosynthesis of its secondary metabolites.Flavonoids are natural compounds that possess many important biological activities,playing a significant role in the medicina... Salt stress inhibits plant growth and affects the biosynthesis of its secondary metabolites.Flavonoids are natural compounds that possess many important biological activities,playing a significant role in the medicinal activity of Eucommia ulmoides(E.ulmoides).To investigate the mechanism by which salt stress affects the biosynthesis of flavonoids in E.ulmoides,a comprehensive analysis of metabolomics and transcriptomics was conducted.The results indicated that salt stress led to the wilting and darkening of E.ulmoides leaves,accompanied by a decrease in chlorophyll levels,and significantly induced malondialdehyde(MDA)and relative electrical conductivity.During salt stress,most metabolites in the flavonoid biosynthesis pathway of E.ulmoides were upregulated,indicating that flavonoid biosynthesis is likely the main induced pathway under salt stress.Among them,secondary metabolites such as 6-Hydroxyluteolin and Quercetin are likely key metabolites induced by salt stress.The correlation analysis of transcriptomics and metabolomics revealed that EuSHT is a hub gene induced by salt stress,promoting the production of flavonoids such as 6-Hydroxyluteolin.The co-expression network showed a strong positive correlation between EuSHT and the biosynthesis of 6-Hydroxyluteolin and Quercetin,while it exhibited a negative correlation with Catechin biosynthesis.The branches leading to Luteolin and Dihydroquercetin are likely the main pathways for flavonoid compound biosynthesis in the plant stress response during salt stress.The results of this study provided a preliminary mechanism of secondary metabolites such as flavonoids in the medicinal plant E.ulmoides induced by salt stress and provided new theoretical support for discussing the mechanism of plant stress response.It also provided useful information for subsequent exploration of resistance genes in E.ulmoides. 展开更多
关键词 Eucommia ulmoides flavonoid salt stress TRANSCRIPTOMICS widely targeted metabolomics
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Privacy Preservation in IoT Devices by Detecting Obfuscated Malware Using Wide Residual Network
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作者 Deema Alsekait Mohammed Zakariah +2 位作者 Syed Umar Amin Zafar Iqbal Khan Jehad Saad Alqurni 《Computers, Materials & Continua》 SCIE EI 2024年第11期2395-2436,共42页
The widespread adoption of Internet of Things(IoT)devices has resulted in notable progress in different fields,improving operational effectiveness while also raising concerns about privacy due to their vulnerability t... The widespread adoption of Internet of Things(IoT)devices has resulted in notable progress in different fields,improving operational effectiveness while also raising concerns about privacy due to their vulnerability to virus attacks.Further,the study suggests using an advanced approach that utilizes machine learning,specifically the Wide Residual Network(WRN),to identify hidden malware in IoT systems.The research intends to improve privacy protection by accurately identifying malicious software that undermines the security of IoT devices,using the MalMemAnalysis dataset.Moreover,thorough experimentation provides evidence for the effectiveness of the WRN-based strategy,resulting in exceptional performance measures such as accuracy,precision,F1-score,and recall.The study of the test data demonstrates highly impressive results,with a multiclass accuracy surpassing 99.97%and a binary class accuracy beyond 99.98%.The results emphasize the strength and dependability of using advanced deep learning methods such as WRN for identifying hidden malware risks in IoT environments.Furthermore,a comparison examination with the current body of literature emphasizes the originality and efficacy of the suggested methodology.This research builds upon previous studies that have investigated several machine learning methods for detecting malware on IoT devices.However,it distinguishes itself by showcasing exceptional performance metrics and validating its findings through thorough experimentation with real-world datasets.Utilizing WRN offers benefits in managing the intricacies of malware detection,emphasizing its capacity to enhance the security of IoT ecosystems.To summarize,this work proposes an effective way to address privacy concerns on IoT devices by utilizing advanced machine learning methods.The research provides useful insights into the changing landscape of IoT cybersecurity by emphasizing methodological rigor and conducting comparative performance analysis.Future research could focus on enhancing the recommended approach by adding more datasets and leveraging real-time monitoring capabilities to strengthen IoT devices’defenses against new cybersecurity threats. 展开更多
关键词 Obfuscated malware detection IoT devices Wide Residual Network(WRN) malware detection machine learning
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On Spanning Wide Diameter of Graphs
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作者 WANG Yameng YIMINGJIANG Shabier 《新疆大学学报(自然科学版中英文)》 CAS 2024年第5期571-578,590,共9页
A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt... A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt)=V(G)then Ct(u,v)is called a spanning t-container,denoted by C_(t)^(sc)(u,v).The length of C_(t)^(sc)(u,v)={P_(1),P_(2),···,Pt}is l(C_(t)^(sc)(u,v))=max{l(P_(i))|1≤i≤t}.A graph G is spanning t-connected if there exists a spanning t-container between any two distinct vertices u and v in G.Assume that u and v are two distinct vertices in a spanning t-connected graph G.Let D_(t)^(sc)(u,v)be the collection of all C_(t)^(sc)(u,v)’s.Define the spanning t-wide distance between u and v in G,d_(t)^(sc)(u,v)=min{l(C_(t)^(sc)(u,v))|C_(t)^(sc)(u,v)∈D_(t)^(sc)(u,v)},and the spanning t-wide diameter of G,D_(t)^(sc)(G)=max{d_(t)^(sc)(u,v)|u,v∈V(G)}.In particular,the spanning wide diameter of G is D_(κ)^(sc)(G),whereκis the connectivity of G.In the paper we provide the upper and lower bounds of the spanning wide diameter of a graph,and show that the bounds are best possible.We also determine the exact values of wide diameters of some well known graphs including Harary graphs and generalized Petersen graphs et al.. 展开更多
关键词 CONNECTIVITY spanning connectivity spanning laceability wide diameter spanning wide diameter
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Rectangular tunnel heading stability in three dimensions and its predictive machine learning models
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作者 Jim Shiau Suraparb Keawsawasvong +3 位作者 Van Qui Lai Thanachon Promwichai Viroon Kamchoom Rungkhun Banyong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4683-4696,共14页
Tunnel heading stability in two dimensions(2D)has been extensively investigated by numerous scholars in the past decade.One significant limitation of 2D analysis is the absence of actual tunnel geometry modeling with ... Tunnel heading stability in two dimensions(2D)has been extensively investigated by numerous scholars in the past decade.One significant limitation of 2D analysis is the absence of actual tunnel geometry modeling with a considerable degree of idealization.Nevertheless,it is possible to study the stability of tunnels in three dimensions(3D)with a rectangular shape using finite element limit analysis(FELA)and a nonlinear programming technique.This paper employs 3D FELA to generate rigorous solutions for stability numbers,failure mechanisms,and safety factors for rectangular-shaped tunnels.To further explore the usefulness of the produced results,multivariate adaptive regression spline(MARS)is used for machine learning of big dataset and development of design equations for practical design applications.The study should be of great benefit to tunnel design practices using the developed equations provided in the paper. 展开更多
关键词 Wide rectangular tunnel Finite element limit analysis(FELA) Multivariate adaptive regression spline(MARS) Three dimensions(3D) Stability analysis
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