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Chinese Physics B 2024年第6期33卷 405-411页

作者：张化远 Kazuhei Wakiya Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish graduate school of science and engineering Iwate UniversityMorioka 020-8551Japan

We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 *** PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic ***,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground *** discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions.

关键词： ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect

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Zn Dissolution-Passivation Behavior with ZnO Formation via In Situ Characterizations

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Energy & Environmental Materials 2024年第1期7卷 197-204页

作者： Tanyanyu Wang Masahiro Kunimoto Masahiro Yanagisawa Masayuki Morita Takeshi Abe Takayuki Homma graduate school of Advanced science and engineering Waseda University Office of Society-Academia Collaboration for Innovation Kyoto University graduate school of engineering Kyoto University Kyoto daigaku-katsura

In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical *** Zn passivation during galvanostatic anodization merely follows the dissolution-precipitation model,whereas that of potentiodynamic polarization exhibits different behaviors in different potential ranges.

关键词： in situ characterization Zn dissolution and passivation ZnO formation

Solid-state NMR of the retinal protonated Schiff base in microbial rhodopsins

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Magnetic Resonance Letters 2024年第3期4卷 11-18页

作者： Sari Kumagai Izuru Kawamura graduate school of engineering science Yokohama National UniversityYokohama240-8501Japan

Rhodopsin is a seven-helical transmembrane protein with a retinal chromophore covalently bound to a conserved lysine in helix G via a retinal protonated Schiff base(RPSB).Microbial rhodopsins absorb light through chromophore and play a fundamental role in *** microbial rhodopsins have been discovered,contributing to diverse functions and ***-state NMR spectroscopy has been instrumental in elucidating the conformation of chromophores and the three-dimensional structure of microbial *** review focuses on the 15N chemical shift values of RPSB and summarizes recent progress in the *** displayed the correlation between the 15N isotropic chemical shift values of RPSB and the maximum absorption wavelength of rhodopsin using solid-state NMR spectroscopy.

关键词： Membrane proteins Microbial rhodopsin Retinal Solid-state NMR Protonated Schiff base

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Robust zero-watermarking algorithm based on discrete wavelet transform and daisy descriptors for encrypted medical image

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

作者： Yiyi Yuan Jingbing Li Jing Liu Uzair Aslam Bhatti Zilong Liu Yen-wei Chen school of Information and Communication engineering Hainan UniversityHaikouChina Research Center for Healthcare Data science Zhejiang LabHangzhouChina graduate school of Information science and engineering Ritsumeikan University ShigaJapan

In the intricate network environment,the secure transmission of medical images faces challenges such as information leakage and malicious tampering,significantly impacting the accuracy of disease diagnoses by medical *** address this problem,the authors propose a robust feature watermarking algorithm for encrypted medical images based on multi-stage discrete wavelet transform(DWT),Daisy descriptor,and discrete cosine transform(DCT).The algorithm initially encrypts the original medical image through DWT-DCT and Logistic ***,a 3-stage DWT transformation is applied to the encrypted medical image,with the centre point of the LL3 sub-band within its low-frequency component serving as the sampling *** Daisy descriptor matrix for this point is then ***,a DCT transformation is performed on the Daisy descriptor matrix,and the low-frequency portion is processed using the perceptual hashing algorithm to generate a 32-bit binary feature vector for the medical *** scheme utilises cryptographic knowledge and zero-watermarking technique to embed watermarks without modifying medical images and can extract the watermark from test images without the original image,which meets the basic re-quirements of medical image *** embedding and extraction of water-marks are accomplished in a mere 0.160 and 0.411s,respectively,with minimal computational *** results demonstrate the robustness of the algorithm against both conventional attacks and geometric attacks,with a notable performance in resisting rotation attacks.

关键词： daisy descriptor DCT DWT encryption domain medical image zero-watermarking

Programmable directional color dynamics using plasmonics

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Microsystems & Nanoengineering 2024年第1期10卷 325-334页

作者： Gyurin Kim Doeun Kim Soeun Ko Jang-Hwan Han Juhwan Kim Joo Hwan Ko Young Min Song Hyeon-Ho Jeong school of Electrical engineering and Computer science Gwangju Institute of Science and TechnologyGwangju 61005Republic of Korea Department of Semiconductor engineering Gwangju Institute of Science and TechnologyGwangju 61005Republic of Korea Artificial Intelligence(AI)graduate school Gwangju Institute of Science and TechnologyGwangju 61005Republic of Korea

Adaptive multicolor filters have emerged as key components for ensuring color accuracy and resolution in outdoor visual ***,the current state of this technology is still in its infancy and largely reliant on liquid crystal devices that require high voltage and bulky structural ***,we present a multicolor nanofilter consisting of multilayered‘active’plasmonic nanocomposites,wherein metallic nanoparticles are embedded within a conductive polymer *** nanocomposites are fabricated with a total thickness below 100 nm using a‘lithography-free’method at the wafer level,and they inherently exhibit three prominent optical modes,accompanying scattering phenomena that produce distinct dichroic reflection and transmission ***,a pivotal achievement is that all these colors are electrically manipulated with an applied external voltage of less than 1 V with 3.5 s of switching speed,encompassing the entire visible ***,this electrically programmable multicolor function enables the effective and dynamic modulation of the color temperature of white light across the warm-to-cool spectrum(3250 K-6250 K).This transformative capability is exceptionally valuable for enhancing the performance of outdoor optical devices that are independent of factors such as the sun’s elevation and prevailing weather conditions.

关键词： directional prevailing exceptional

Double DQN Method For Botnet Traffic Detection System

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Computers, Materials & Continua 2024年第4期79卷 509-530页

作者： Yutao Hu Yuntao Zhao Yongxin Feng Xiangyu Ma school of Information science and engineering Shenyang Ligong UniversityShenyang110159China graduate school Shenyang Ligong UniversityShenyang110159China

In the face of the increasingly severe Botnet problem on the Internet,how to effectively detect Botnet traffic in realtime has become a critical *** the existing deepQnetwork(DQN)algorithminDeep reinforcement learning can solve the problem of real-time updating,its prediction results are always higher than the actual *** Botnet traffic detection,although it performs well in the training set,the accuracy rate of predicting traffic is as high as%;however,in the test set,its accuracy has declined,and it is impossible to adjust its prediction strategy on time based on new data ***,in the new dataset,its accuracy has declined ***,this paper proposes a Botnet traffic detection system based on double-layer DQN(DDQN).Two Q-values are designed to adjust the model in policy and action,respectively,to achieve real-time model updates and improve the universality and robustness of the model under different data *** show that compared with the DQN model,when using DDQN,the Q-value is not too high,and the detectionmodel has improved the accuracy and precision of Botnet ***,when using Botnet data sets other than the test set,the accuracy and precision of theDDQNmodel are still higher than DQN.

关键词： DQN DDQN deep reinforcement learning botnet detection feature classification

Vacuum-free lamination via controlled polymer adhesion for selective photogeneration and photodetection

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Carbon Energy 2024年第7期6卷 205-218页

作者： Min Soo Kim Jihyun Lim Woongsik Jang Dong Hwan Wang Department of Intelligent Semiconductor engineering Chung-Ang UniversitySeoulRepublic of Korea school of integrative engineering Chung-Ang UniversitySeoulRepublic of Korea

This study attempts to develop a reproducible thin-film formation technique called vacuum-free(VF)lamination,which transfers thin films using elastomeric polymer-based laminating ***,by controlling the interface characteristics of the mediator based on the work of adhesion,VF lamination is successfully performed for various thicknesses(from 20 to 240 nm)of a conjugated photoactive material composed of poly[(2,6-(4,8-bis(5-(2-ethylhexyl-3-fluoro)thiophen-2-yl)-benzo[1,2-b:4,5-bʹ]dithiophene))-alt-(5,5-(1ʹ,3ʹ-di-2-thienyl-5ʹ,7ʹ-bis(2-ethylhexyl)benzo[1ʹ,2ʹ-c:4ʹ,5ʹ-cʹ]dithiophene-4,8-dione)](a polymer donor)and 2,2ʹ-((2Z,2ʹZ)-((12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2ʹʹ,3ʹʹ:4ʹ,5ʹ]thieno[2ʹ,3ʹ:4,5]pyrrolo[3,2-g]thieno[2ʹ,3ʹ:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(a nonfullerene acceptor).Interestingly,the organic photovoltaic and photodetecting applications,prepared by the VF lamination process,showed superior performance compared to those of devices prepared by conventional *** is due to the overturned surface morphology,which led to enhanced charge transport ability and blocking of the externally injected ***,the reproducible VF lamination process,exploiting an adhesion-based elastomeric polymer mediator,is a promising thin-film formation technique for developing efficient next-generation organic optoelectronic materials consistent with the solution process.

关键词： conjugated nonfullerene acceptor photodetectors photovoltaics polymer vacuum-free lamination

Multiple-dimensioned defect engineering for graphite felt electrode of vanadium redox flow battery

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Carbon Energy 2024年第2期6卷 143-153页

作者： Yingqiao Jiang Yinhui Wang Gang Cheng Yuehua Li Lei Dai Jing Zhu Wei Meng Jingyu Xi Ling Wang Zhangxing He school of Chemical engineering North China University of Science and TechnologyTangshanChina Tsinghua Shenzhen International graduate school Institute of Materials ResearchTsinghua UniversityShenzhenChina

The scarcity of wettability,insufficient active sites,and low surface area of graphite felt(GF)have long been suppressing the performance of vanadium redox flow batteries(VRFBs).Herein,an ultra-homogeneous multipledimensioned defect,including nano-scale etching and atomic-scale N,O codoping,was used to modify GF by the molten salt ***_(4)Cl and KClO_(3) were added simultaneously to the system to obtain porous N/O co-doped electrode(GF/ON),where KClO_(3) was used to ultra-homogeneously etch,and O-functionalize electrode,and NH4Cl was used as N dopant,***/ON presents better electrochemical catalysis for VO_(2)+/VO_(2)+ and V3+/V2+ reactions than only O-functionalized electrodes(GF/O)and *** enhanced electrochemical properties are attributed to an increase in active sites,surface area,and wettability,as well as the synergistic effect of N and O,which is also supported by the density functional theory ***,the cell using GF/ON shows higher discharge capacity,energy efficiency,and stability for cycling performance than the pristine cell at 140 mA cm^(−2) for 200 ***,the energy efficiency of the modified cell is increased by 9.7% from 55.2% for the pristine cell at 260 mA cm^(−2).Such an ultra-homogeneous etching with N and O co-doping through“boiling”molten salt medium provides an effective and practical application potential way to prepare superior electrodes for VRFB.

关键词： graphite felt molten salt N O co-doping ultra-homogeneous etching vanadium redox flow battery

Efficient flexible perovskite solar cells and modules using a stable SnO_(2)-nanocrystal isopropanol dispersion

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Nano Research 2024年第4期17卷 2704-2711页

作者： Zhiwei Su Jing Li Ruixuan Jiang Shujie Zhang Chengkai Jin Feng Ye Bingcan Ke Mengjun Zhou Jinhui Tong Hyesung Park Fuzhi Huang Yi-Bing Cheng Tongle Bu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China school of Material science and engineering Wuhan University of TechnologyWuhan 430070China Department of Materials science and engineering Graduate School of Semiconductor Materials and Devices EngineeringGraduate School of Carbon NeutralityLow Dimensional Carbon Materials CenterUlsan National Institute of Science and TechnologyUlsan 44919Republic of Korea Xianhu Laboratory of the Advanced Energy science and Technology Guangdong Laboratory Foshan 528200China

The outstanding advantages of lightweight and flexibility enable flexible perovskite solar cells(PSCs)to have great application potential in mobile energy *** to the low cost,low-temperature processibility,and high electron mobility,SnO_(2) nanocrystals have been widely employed as the electron transport layer in flexible *** prepare high-quality SnO_(2) layers,a monodispersed nanocrystal solution is normally ***,the SnO_(2) nanocrystals can easily aggregate,especially after long periods of ***,we develop a green and cost-effective strategy for the synthesis of high-quality SnO_(2) nanocrystals at low temperatures by introducing small molecules of glycerol,obtaining a stable and well-dispersed SnO_(2)-nanocrystal isopropanol dispersion *** to the enhanced dispersity and super wettability of this alcohol-based SnO_(2)-nanocrystal solution,large-area smooth and dense SnO_(2) films are easily deposited on the plastic conductive ***,this contributes to effective charge transfer and suppressed non-radiative recombination at the interface between the SnO_(2) and perovskite *** a result,a greatly enhanced power conversion efficiency(PCE)of 21.8%from 19.2%is achieved for small-area flexible PSCs.A large-area 5 cm×5 cm flexible perovskite solar mini-module with a champion PCE of 16.5%and good stability is also demonstrated via this glycerol-modified SnO_(2)-nanocrystal isopropanol dispersion approach.

关键词： tin oxide isopropanol dispersion colloid stability flexible perovskite solar cells

22 kW near-diffraction-limited Yb:YAG slab laser amplifier without adaptive optics correction

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Chinese Optics Letters 2024年第3期22卷 65-70页

作者：汪丹何平周唐建李密邬映臣王亚楠尚建力高清松张凯唐淳朱日宏 school of Electronic and Optical engineering Nanjing University of Science and TechnologyNanjing 210094China Institute of Applied Electronics China Academy of Engineering PhysicsMianyang 430079China graduate school of China Academy of engineering Physics Beijing 100193China

A high-power CW Yb:YAG slab laser amplifier with no adaptive optics correction has been experimentally *** room temperature,the amplifier emits a power of 22 kW with an average beam quality(β)of less than 3 in 0.5 *** our knowledge,this is the brightest slab laser without closed-loop adaptive optics demonstrated to *** addition,an extracted power of 17 kW with an optical extraction efficiency of 33%,corresponding to a residual optical path difference of less than 0.5μm,is achieved with the single Yb:YAG slab gain *** slab gain module has the potential to be scalable to higher powers while maintaining good beam *** makes a high-power solid-state laser system simpler and more robust.

关键词： laser amplifier Yb:YAG slab laser surface quality pumping uniformity

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