bluuebunny/crossref_metadata_2025_split huggingface dataset:
Attack detection and mitigation using optimal deep maxout network in cloud computing
Authors: Patil Shubangini , Patil Rekha 
Published: June 2022

SummaryCloud computing is a promising technique and the majority of information technology based services function in this infrastructure, which addresses the need of today's data center. There involve privacy and security problems in the cloud, which affected the utility of the cloud. Various mitigation solutions are developed in existing, in which the attacks continue to elevate in frequency and severity. This calls for a model for addressing the needs of challenging security threats. This article devises novel attack detection and mitigation technology using an optimization‐driven deep learning model. Here, the system comprises five modules, like data, data owner, cloud server, cloud user, and thin provision virtual volume. Here, each entity performs its own operations. The proposed technique includes five stages, namely, authentication phase, data sharing and communication phase, recorded log file creation phase, attack detection phase, and attack mitigation phase. An initial phase is the authentication phase where an authentication protocol is modeled using different mathematical functionalities. Once the authentication is done, the data sharing and communication are initiated for sharing the sensitive data. Thereafter the log file creation phase is initiated for storing the log entries. Then the attack detection is performed utilizing deep maxout network that is tuned by the developed gray wolf political optimizer (GWPO). The GWPO is the integration of gray wolf optimizer (GWO) and political optimizer (PO). Finally, attack mitigation is performed by reducing the data rates of attack nodes. The developed GWPO‐enabled deep maxout network provided improved performance with the highest accuracy of 97.9%, true positive rate of 97.3%, and true negative rate of 97.7%.
Strategies for Regenerative Vascular Tissue Engineering
Authors: Wang Yao , Keshavarz Mozhgan , Barhouse Patrick , Smith Quinton 
Published: June 2022

AbstractVascularization remains one of the key challenges in creating functional tissue‐engineered constructs for therapeutic applications. This review aims to provide a developmental lens on the necessity of blood vessels in defining tissue function while exploring stem cells as a suitable source for vascular tissue engineering applications. The intersections of stem cell biology, material science, and engineering are explored as potential solutions for directing vascular assembly.
Activating Oxygen Redox in Layered NaxMnO2 to Suppress Intrinsic Deficient Behavior and Enable Phase‐Transition‐Free Sodium Ion Cathode
Authors: Wang Feng , Peng Bo , Zeng Suyuan , Zhao Liping , Zhang Xiaolei , Wan Guanglin , Zhang Hongli , Zhang Genqiang 
Published: June 2022

AbstractP2‐type layered NaxMnO2 cathode shows great potential in practical sodium ion batteries, especially for grid‐level applications due to its eco‐friendly and cost‐effective sodium and manganese resources, and high theoretical specific capacity. However, several obstacles including severe phase transitions of P2‐O2 and P2‐P2′, low redox potential of Mn3+/Mn4+, disproportionation reaction and Jahn‐Teller distortion of Mn3+, and deficient behavior have already hindered its practical applications. Herein, a Li, Cu co‐doping strategy to tackle the mentioned obstacles by activating the oxygen redox is presented. The Li, Cu co‐doped material exhibits solid solution reaction without any phase transitions as proved by in situ X‐ray diffraction measurement and reduces the dissolution of active manganese element. With this modification treatment, it can dramatically raise the cycling stability from 30.4% to 80.1% after 150 cycles and simultaneously improves the deficient behavior due to the capacity contribution of oxygen redox at high voltage. More importantly, the coin‐cell type sodium ion full cell assembled with this cathode and commercial hard carbon anode delivers a promising energy density of 225.1 Wh kg–1.
Edge‐Enriched Mo2TiC2Tx/MoS2 Heterostructure with Coupling Interface for Selective NO2 Monitoring
Authors: Zhao Qiuni , Zhou Wenzhe , Zhang Mingxiang , Wang Yang , Duan Zaihua , Tan Chaoliang , Liu Bohao , Ouyang Fangping , Yuan Zhen , Tai Huiling , Jiang Yadong 
Published: June 2022

AbstractEndowed with rich terminal groups, good electrical conductivity, and controllable structure, transition metal carbides/nitrides (MXenes) have attracted extensive attention for potential application in gas sensor, but long‐standing challenges of the MXenes (titanium carbide as the representative) are their limited selectivity and sensitivity. Herein, a high‐active double transition‐metal titanium molybdenum carbide (Mo2TiC2Tx) with superstrong surface adsorption (−3.12 eV) for NO2 gas molecule is proposed, and it is further coupled with molybdenum disulfide (MoS2) by interface modulation to construct an edge‐enriched heterostructure. Due to the synergistic effect of strong adsorption, rich adsorption sites, and coupling interface of Mo2TiC2Tx/MoS2 composite, the as‐fabricated Mo2TiC2Tx/MoS2 gas sensor exhibits an outstanding response toward NO2 with high selectivity against various interference gases, which is well supported by density functional theory calculations. Meanwhile, the sensor exhibits a sensitivity of 7.36% ppm−1, detection limit of 2.5 ppb, and reversibility at room temperature. A portable, wireless NO2 monitoring system is demonstrated for gas leakage searching and dangerous warning based on Mo2TiC2Tx/MoS2 gas sensor. This work facilitates the gas sensing application of MXenes, and provides an avenue for the development of wireless sensing system in environmental monitoring and safety assurance.
Tunable Ferroelectricity in Van der Waals Layered Antiferroelectric CuCrP2S6
Authors: Cho Kwanghee , Lee Seungyeol , Kalaivanan Raju , Sankar Raman , Choi Kwang‐Yong , Park Soonyong 
Published: June 2022

AbstractRecent success in experimental and theoretical works on metal thiophosphates (MTPs) paved the way to add multiple functionalities of complex oxides, such as ferroelectricity, in 2D materials. To realize multiferroicity and magnetoelectric coupling on layered van der Waals materials, incorporating magnetic ions in the ferroelectric framework is desirable. Unfortunately, replacing the metal ion with a magnetic one in MTPs results in antiferroelectricity in which spontaneous macroscopic polarization is absent. Herein, the emergence of a tunable local ferroelectric state in antiferroelectric CuCrP2S6 possessing magnetic Cr3+ ion is reported. The spontaneous macroscopic polarization is observed, which is switchable by an external poling field through controlling a defect‐dipole polarization in the quasi‐antipolar state. The observations suggest that the formation of defect dipoles, which is facilitated by an order‐disorder‐type structural transition, is likely related to a metastable Cu site within the van der Waals gap and therefore is a smoking gun of the existence of a uniaxial quadruple potential well. The interaction between the defect‐dipole polarization and dipoles in the antipolar matrix may lead to the emerging local ferroelectricity in antiferroelectric CuCrP2S6. The findings suggest a possibility of utilizing the local ferroelectricity of multiferroic MTPs for novel 2D applications.
Anion‐Induced Catalytic Reaction in a Solution‐Processed Molybdenum Oxide for Efficient Inverted Ternary Organic Photovoltaics
Authors: Ki Taeyoon , Lee Changhoon , Kim Jehan , Hwang In‐Wook , Oh Chang‐Mok , Park Kiyoung , Lee Sanseong , Kim Ju‐Hyeon , Balamurugan Chandran , Kong Jaemin , Jeong Hyeon‐Seok , Kwon Sooncheol , Lee Kwanghee 
Published: June 2022

AbstractSolution‐processed transition metal oxides (TMOs) prepared from complex ion precursors are developed as promising scalable interfacial layers for non‐fullerene organic photovoltaics (OPVs); however, challenges remain in achieving defect‐free and highly oriented metal‐oxygen networks without post‐deposition treatments due to the presence of residual organic metal‐binding ligands in films. Herein, the novel strategy that the problematic organic metal‐binding ligands in TMO precursors can be successfully eliminated by an anion‐induced catalytic reaction (ACR) at room temperature is demonstrated, in which the low‐level anions induce electron redistribution and instability of TMO precursors, expediting binding ligand removal during the hydrolysis reaction. The subsequent condensation process facilitates a dimensionally confined and continuous metal‐oxygen network with a 20‐fold increase in electrical conductivity (from 8.4 × 10−4 to 1.8 × 10−2 S m−1) and superior work function tunability (from 5.1 to 5.3 eV) compared to the pristine film. The ACR‐derived TMO thin film on top of a ternary PBDB‐TF:Y6:PC71BM photoactive layer enables an inverted device configuration with improved efficiency of 17.6%, as well as enhanced stability over 70% of the initial efficiency for up to 100 h AM 1.5G illumination.
Rashba–Edelstein Effect in the h‐BN Van Der Waals Interface for Magnetization Switching
Authors: Xie Qidong , Lin Weinan , Liang Jinghua , Zhou Hengan , Waqar Moaz , Lin Ming , Teo Siew Lang , Chen Hao , Lu Xiufang , Shu Xinyu , Liu Liang , Chen Shaohai , Zhou Chenghang , Chai Jianwei , Yang Ping , Loh Kian Ping , Wang John , Jiang Wanjun , Manchon Aurelien , Yang Hongxin , Chen Jingsheng 
Published: June 2022

AbstractVan der Waals materials are attracting great attention in the field of spintronics due to their novel physical properties. For example, they are utilized as spin‐current generating materials in spin–orbit torque (SOT) devices, which offers an electrical way to control the magnetic state and is promising for future low‐power electronics. However, SOTs have mostly been demonstrated in vdW materials with strong spin–orbit coupling (SOC). Here, the observation of a current‐induced SOT in the h‐BN/SrRuO3 bilayer structure is reported, where the vdW material (h‐BN) is an insulator with negligible SOC. Importantly, this SOT is strong enough to induce the switching of the perpendicular magnetization in SrRuO3. First‐principles calculations suggest a giant Rashba effect at the interface between vdW material and SrRuO3 (110)pc thin film, which leads to the observed SOT based on a simplified tight‐binding model. Furthermore, it is demonstrated that the current‐induced magnetization switching can be modulated by the electric field. This study paves the way for exploring the current‐induced SOT and magnetization switching by integrating vdW materials with ferromagnets.
Cluster‐Glass for Low‐Cost White‐Light Emission
Authors: Rojas‐León Irán , Christmann Jan , Schwan Sebastian , Ziese Ferdinand , Sanna Simone , Mollenhauer Doreen , Rosemann Nils W. , Dehnen Stefanie 
Published: June 2022

AbstractThe development of efficient and high‐brilliance white‐light sources is an essential contribution to innovative emission technologies. Materials exhibiting strong nonlinear optical properties, in particular second‐harmonic generation (SHG) or white‐light generation (WLG), have therefore been investigated with great activity in recent times. While many new approaches have been reported until now, the processability of the compounds remains a challenge. Here, a new class of materials, denoted as “cluster‐glass”, which do not only show superior white‐light emission properties upon irradiation by an inexpensive continuous‐wave infrared laser diode, but can be easily accommodated in size and shape by formation of robust glassy solids, is introduced. The cluster‐glass materials are fabricated by mild heating from crystalline powders of adamantane‐type clusters exhibiting a quaternary, inorganic–organic hybrid cluster core [(PhSi)(CH2)3(PhSn)E3] (E = S, Se, Te). The process is fully reversible and preserves the integrity of the clusters in the glass, as proven by solution spectroscopy and recrystallization. Theoretical studies corroborate the importance of the quaternary nature of the cluster cores for the observed structural and optical phenomena. Thanks to these findings, high‐brilliance white‐light sources can be synthesized in form of stable, robust glass of any shape, which ultimately renders them suitable for everyday's applications.
Hydrophilic/Hydrophobic SiO2 Nanoparticles Enabled Janus‐Type Paper through Commercial Glaco Spraying and Air‐Plasma Treatment
Authors: Xu Bing , Ding Yinlong 
Published: June 2022

AbstractFunctional paper‐based microdevices have been receiving wide attention in the research areas of microfluidic chips, soft actuators, etc. This work introduces the design and fabrication of a Janus‐type paper in which one side of the paper remains hydrophilic and the other side is hydrophobic. Such Janus‐type paper is prepared by directly spraying hydrophobic Glaco solutions and following air plasma treatment. The former treatment can cover the paper fibers with numerous hydrophobic SiO2 nanoparticles. Through optimizing the fabrication parameters of the air plasma, it can penetrate the filter paper in a controllable depth, resulting in effectively regulating the hydrophobic particles into hydrophilic ones. Thereafter, the antirotation and interfacial stability of the Janus paper are investigated. Finally, a liquid storage and contamination‐free analysis devices are demonstrated on the Janus‐type paper platform. Noting that the commercially nonfluoride coating (Glaco) and mature plasma instrument together make the fabrication method simple, rapid, users/environmental‐friendly, and mass‐produced. The method provides a new route to fabricate Janus‐type paper for potential multifunctional applications in microfluidic chips and smart actuators, and may open up new avenue to prepare Janus films in a simple/rapid way.
Inkjet Printing Efficient Defined‐Pixel Matrix Perovskite Light‐Emitting Diodes with a Polar Polymer Modification Layer
Authors: Wang Junjie , Li Danyang , Luo Yu , Wang Jian , Peng Junbiao 
Published: June 2022

AbstractPerovskite light‐emitting diodes (PeLEDs) for full‐color displays based on inkjet printing technology are increasingly attractive. For potential applications, fabricating high‐quality perovskite films with defined‐pixel sizes is crucially important. The key issue is how to control the contact properties between the perovskite ink and a hole transport layer (HTL). In this study, a novel strategy is proposed by using the poly[(9,9‐bis(3′‐((N,N‐dimethyl)‐N‐ethylammonium)‐propyl)‐2,7‐fluorene)‐alt‐2,7‐(9,9‐dioctylfluorene)] dibromide (PFN‐Br) polar polymer to modify the HTL surface, instead of conventional O2 plasma method. The PFN‐Br can enhance the surface energy of HTLs, including PVK, Poly‐TPD, TFB, etc., and improve the wettability of perovskite inks on the HTL due to its polar quaternary ammonium groups. Besides, the PFN‐Br acts as the easier nucleation to induce a tiny crystallization of perovskites. On the other hand, the diphenyl phosphate liver (DPA) is first used to mix in perovskite inks to optimize the perovskite film phase distribution and the elimination of uncoordinated Pb2+, resulting from interactions between PEA+ and DPA, Pb2+ and DPA, respectively. As a result, a defined‐pixel matrix green quasi‐2D PeLED with the peak external quantum efficiency over 10% via inkjet printing technique is achieved, which is the most efficient matrix green PeLEDs fabricated by inkjet printing technique so far.
High‐Efficiency E‐Beam Pumped Deep‐Ultraviolet Surface Emitter Based on AlGaN Ultra‐Thin Staggered Quantum Wells
Authors: Wang Yixin , Yuan Ye , Tao Renchun , Liu Shangfeng , Wang Tao , Sheng Shanshan , Quach Patrick , CM Manoj Kumar , Chen Zhaoying , Liu Fang , Rong Xin , Jin Peng , Feng Mengyang , Li Hongwei , Guo Shiping , Ge Weikun , Lee June Key , Shen Bo , Wang Xinqiang 
Published: June 2022

AbstractA 2‐inch wafer‐scale electron‐beam (e‐beam) pumped deep‐ultraviolet surface emitter (DUVSE) with high efficiency and high output power at an emission wavelength of 248 nm is reported. This DUVSE benefits from ultra‐thin staggered AlN/AlGaN/GaN multiple quantum wells (MQWs), which compromise the electron–hole overlap and carrier confinement and thus significantly improve the emission efficiency. The wall‐plug‐efficiency (WPE) is increased by six times to 5.25% in comparison to that of conventional DUV light‐emitting devices (LEDs) based on AlGaN MQWs. This WPE is achieved under an anode voltage and current of 8 kV and 1 mA, where the output power is 420 mW. This output power can be further enhanced to 702 mW by increasing the anode current to 3 mA. The enhanced WPE and uniform electron beam distribution lighten the avenue to achieve a wafer‐scale high power dense DUV light source, which is a challenge for conventional DUV‐LEDs, in particular with an emission wavelength of less than 250 nm.
Flexible THz Carrier‐Envelope Phase Shifter Based on Metamaterials
Authors: Li Tong , Quan Baogang , Fang Guangyou , Wang Tianwu 
Published: June 2022

AbstractThe ability to manipulate terahertz (THz) waveform is important for its applications. Despite rapid progress in metamaterials (MMs), the carrier‐envelope phase (CEP) control for THz pulse is still challenging due to its broadband feature. THz scanning tunneling microscope (THz‐STM), as an emerging technique combining both high temporal and spatial resolution, imposes additional requirements. Here, an ultra‐thin and flexible THz CEP shifter with five groups of different MM arrays is proposed. The CEP shifter is based on a specified split‐ring resonator with a pair of cross‐oriented gratings to enhance transmission efficiency. Simulation and experimental results show that the CEP of the THz pulse is modulated by passing through different MM arrays in turn, which can be shifted as high as 2π. The CEP shifter has good tolerance to wide‐angle oblique incidence and structural bending, which is expected to be used as a key component for THz‐STM. The structure of the CEP shifter has many potential applications, including THz wave focusing, beam‐steering, spatial phase modulation, and structured light generation.
Blue Light Emitting Diodes based on Bright Quasi‐Type‐II ZnO@1‐Aminopyrene Hybrid Quantum Dots with a Long Operation Life
Authors: Kim Hong Hee , Park Soohyung , Ko Keum‐Jin , Yim Sang‐Youp , Kang Jae‐Wook , Choi Won Kook 
Published: June 2022

AbstractNon‐toxic heavy metal, low‐cost indium‐free blue emissive quantum dots (QDs) are critical for the realization of self‐emissive electroluminescent quantum dot (ELQD) light‐emitting diode (LED) displays. A facile and effective hybridization of ZnO QDs with functionalized polyaromatic hydrocarbons (f‐PAHs) to synthesize a very bright and stable blue‐light emissive quantum‐dot LED (QLED) using non‐toxic quasi‐type‐II ZnO@1‐Aminopyrene hybrid QDs is reported. The optimized QLEDs of ITO/PEDOT:PSS/TFB/ZnO@1‐Aminopyrene/TPBi/LiF/Al demonstrate very bright deep blue‐light electroluminescence of 3379 cd m−2 centered at λ = 441 nm with a full‐width‐at‐half maximum of 41.7 nm and CIE 1931 color coordinates of 0.17 and 0.09, a luminous efficacy of 3.32 cd A−1, power efficiency of 2.45 lm W−1, external quantum efficiency of 2.35%, and a remarkably long lifetime T50 of >17 830 h at 100 cd m−2.
Periodically Poled Nonlinear Photonic Crystal KTa0.51Nb0.49O3 Combining Wide Transparent Range and Large Quadratic Coefficient
Authors: Wu Yabo , Liu Qilu , Tian Gang , Zheng Limei , Liang Fei , Wang Xuping , Wang Dongzhou , Sang Yuanhua , Liu Hong , Wang Jiyang , Yu Haohai , Zhang Huaijin 
Published: June 2022

AbstractSince the first proposal of quasi‐phase‐matching (QPM) in 1962, finding new nonlinear photonic crystals has been an attractive topic in nonlinear optics fields. However, combining high conversion efficiency and wide operation range concurrently into one single crystal remains a great challenge. Herein, a periodically poled KTa0.51Nb0.49O3 (PPKTN) is fabricated as a one‐dimensional nonlinear photonic crystal for the first time, to the authors’ best knowledge. Benefitting from the large quadratic nonlinear coefficient, the QPM second harmonic generation (SHG) at 1030 nm is realized with a high conversion efficiency of up to 39%. More importantly, KTN crystal possesses wider mid‐infrared spectral transparency (0.4–8.0 µm) than commercialized LiNbO3 and KTiOPO4. A 5 µm SHG is first achieved with a conversion efficiency of 6.3%, indicating that it is a promising candidate for broadband mid‐infrared parametric conversion. This work promotes PPKTN as a new nonlinear photonic platform to achieve highly efficient optical waveguide, holography, information storage, and all‐optical chips.
Synthesis of Bis(β‐Oximinoalkyl)malonates and Their Catalytic Reductive Cyclization to Piperidines
Authors: Pospelov Evgeny V. , Boyko Yaroslav D. , Ioffe Sema L. , Sukhorukov Alexey Yu. 
Published: June 2022

AbstractHitherto unknown bis(β‐oximinoalkyl)malonates were demonstrated to be convenient platforms for the synthesis of saturated N‐heterocycles. Upon heterogeneous catalytic hydrogenation, these dioximes undergo reductive cyclization to give substituted piperidine‐4,4’‐dicarboxylates, which are valuable building blocks in medicinal chemistry. By using dioximes bearing an additional ester group in the side chain, tandem piperidine/pyrrolidinone ring closure leading to indolizidinone framework was showcased in this work. A modular synthesis of initial bis(β‐oximinoalkyl)malonates (both symmetrically and unsymmetrically substituted) was accomplished via a sequential Michael addition of two nitrosoalkene molecules to malonic ester. The mechanism of the reductive cyclization of dioximes to piperidines was investigated by isotope scrambling experiments and isolation of intermediates.magnified image
In Vivo Click Chemistry Enables Multiplexed Intravital Microscopy
Authors: Ko Jina , Lucas Kilean , Kohler Rainer , Halabi Elias A. , Wilkovitsch Martin , Carlson Jonathan C. T. , Weissleder Ralph 
Published: June 2022

AbstractThe ability to observe cells in live organisms is essential for understanding their function in complex in vivo milieus. A major challenge today has been the limited ability to perform higher multiplexing beyond four to six colors to define cell subtypes in vivo. Here, a click chemistry‐based strategy is presented for higher multiplexed in vivo imaging in mouse models. The method uses a scission‐accelerated fluorophore exchange (SAFE), which exploits a highly efficient bioorthogonal mechanism to completely remove fluorescent signal from antibody‐labeled cells in vivo. It is shown that the SAFE‐intravital microscopy imaging method allows 1) in vivo staining of specific cell types in dorsal and cranial window chambers of mice, 2) complete un‐staining in minutes, 3) in vivo click chemistries at lower (µm) and thus non‐toxic concentrations, and 4) the ability to perform in vivo cyclic imaging. The potential utility of the method is demonstrated by 12 color imaging of immune cells in live mice.