检索结果-南通市图书馆

Multiresponsive,easy-reversible,and dual-visual Pt(Ⅱ)salt nanostructures for advanced anti-counterfeiting application

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第1期17卷 372-381页

作者： zhen su§ Depeng Li§ Lixin Zhang Si Tian Yuhong su Xiaoyun Hu Duan Xiong Qingqing Guan Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education College of Chemical EngineeringXinjiang UniversityUrumqi 830017China

Smart materials that integrate multi-stimuli response,full reversibility,and dual-visual read-out channel are highly desired for anticounterfeiting and information encryption ***,we developed a multiresponsive perchlorate terpyridyl Pt(Ⅱ)nano complex which could undergo fully reversible conversion between three forms stimulated by water or formaldehyde molecule due to the extent of Pt–Pt ***,a dual-visual channel,i.e.,the colorimetric channel changed from yellow to orange or red and the corresponding luminescent channel from orange to orange-red or red,has also been *** weak and equivalent strength of ion-dipole interaction and hydrogen bond that generated between formaldehyde/water and Pt(II)salt result in the easy-control reversibility between the three ***,by introducing different polymer matrices,1Cl·ClO_(4)@PMMA(1Cl·ClO_(4):[Pt(tpy)Cl]·ClO4,tpy:2,2':6',2''-terpyridine),PMMA:poly(methyl methacrylate))and 1Cl·ClO4@PVA(PVA:polyvinyl alcohol)are successfully constructed,which exhibit different reversible behaviors since the PMMA and PVA matrix exert different influences on the strength of *** smart Pt(II)salt nanostructures present great potential for high-security-level anticounterfeiting application.

关键词： Pt(II)complex multiresponse reversibility anticounterfeiting information encryption

Multi-carrier Tb/s silicon photonic coherent receiver

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第1期67卷 284-291页

作者： zhen WANG Xingfeng LI Jingchi LI Jian SHEN Yong ZHANG Yikai su State Key Lab of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong University

We propose a silicon polarization-diversity coherent receiver for wavelength-multiplexing transmission without using the large-footprint arrayed waveguide grating(AWG).We have integrated our proposed coherent receiver on the silicon-on-insulator(SOI) platform for high-capacity *** the proposed coherent receiver,high-frequency photocurrent signals from other wavelengths are suppressed by electrical low-pass ***,the signal-signal beat interference(SSBI) generated from each wavelength is eliminated by the balanced *** two features lend to the proposed coherent receiver being free of the mm-scale *** have demonstrated our proposed coherent receiver to detect a 1.12-Tb/s wavelength-division-multiplexed and polarization-division-multiplexed 16-ary quadrature amplitude modulation(PDM-16-QAM) *** compact footprint of the silicon chip promises small-form-factor receivers for future ultra-high-capacity coherent communication systems that require a high integration level and low fabrication cost.

关键词： silicon photonics optical receivers coherent communication wavelength-division-multiplexing(WDM) polarization-division-multiplexing(PDM)

Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2024年第1期26卷 57-66页

作者： Chang-bo Zhao Wei-bo Chen Wen-zhen Wang Fang-Xin Gong Cui-Qin Fan Ye Li Tian Lan Wen-Jing Wang Ming-zhen Yuan Department of Urology Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Andrology Liaocheng People's HospitalShandong UniversityLiaocheng 252000China Department of Urology The Second Hospital of Shandong UniversityJinan 250012China Department of Physiology School of Basic Medical SciencesShandong UniversityJinan 250012China

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction(DMED)a challenging *** factors contributing to DMED include oxidative stress,nitric oxide(NO)/cyclic guanosine monophosphate(cGMP)pathway activation,and apoptosis,while nitro-oleic acid(NO,-OA)has been shown to be beneficial in treating these aspects of this ***,herein,investigated the effects and possible mechanisms of NO,-OA on erectile function as assessed in a streptozotocin-induced rat model of *** results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control ***,in response to 4 weeks of NO,-OA treatment,there was an improvement in erectile *** expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED *** expression of proapoptotic factors was increased,while that of antiapoptotic factors was decreased in the DMED ***,the cell morphology in the cavernous tissue of the DMED group also changed ***,-OA treatment significantly reversed all these changes observed in the DMED *** conclusion,NO,-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress,activation of the NO/cGMP pathway,and a reduction in apoptosis.

关键词： apoptosis diabetic mellitus erectile dysfunction nitro-oleic acid NO/cGMP pathway oxidative stress

Controllable Ring-opening Polymerization ofδ-Valerolactone Catalyzed by Quinolinyl-Urea/MTBD Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第8期42卷 1103-1110页

作者： Xin-Yu Liu Liang Zhu su-Yun Jie bo-Geng Li State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058China

Due to their excellent biocompatibility and biodegradability,aliphatic polyesters are widely used in the biomedical,packaging and agricultural fields,which are usually accessed by the ring-opening polymerization(ROP)of lactones and the catalysts particularly play an important *** a series of quinolinyl-urea catalysts have been synthesized via the reaction between isocyanate and aminoquinoline with an amino group at different substitution positions and *** combination with 7-methyl-1,5,7-triazabicyclo[4,4,0]dec-5-ene(MTBD)as a cocatalyst and benzyl alcohol(BnOH)as an initiator,1-(3,5-bis(trifluoromethyl)phenyl)-3-(quinolin-3-yl)urea(3-QU)was observed to be most active for the ROP ofδ-valerolactone(δ-VL).The polymerization conditions were optimized by varying the type of organic base,catalyst concentration and reaction *** changing the ratio of[M]_0/[I],linear polyvalerolactones(PVLs)with different molecular weights and narrow molecular weight distribution were *** kinetic and chain extension experiments were carried out to prove the"living"/controllable *** the NMR experiments were used to support the proposal of possible mechanism.

关键词： Quinolinyl-urea Ring-opening polymerization PVL

Understanding adversarial attacks on observations in deep reinforcement learning

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第5期67卷 69-83页

作者： You QIAOBEN Chengyang YING Xinning ZHOU Hang su Jun ZHU bo ZHANG Department of Computer Science and Technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack

Preparation of CIP@TiO_(2) composite with broadband electromagnetic wave absorption properties

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 197-205页

作者： Qiang su Hanqun Wang Yunfei He Dongdong Liu Xiaoxiao Huang bo Zhong School of Materials Science and Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Scholars aim for the improved impedance matching (Z) of materials while maintaining their excellent wave absorption properties. Based on the hydrolysis characteristics of isopropyl titanate, a simple preparation process for the coating of carbonyl iron powder(CIP) with TiO_(2) was designed. Given the TiO2coating, the Z of the CIP@TiO_(2) composite was adjusted well by decreasing the dielectric constant. Moreover, the interfacial polarization of CIP@TiO_(2) was enhanced. Ultimately, the electromagnetic-wave (EMW) absorption property of the CIP@TiO_(2)composite was improved substantially, the minimum reflection loss reached-46.07 dB, and the effective absorption bandwidth can reach 8 GHz at the composite thickness of 1.5 mm. Moreover, compared with CIP, the oxidation resistance of CIP@TiO_(2)showed remarkable improvement. The results revealed that the oxidation starting temperature of CIP@TiO_(2) as about 400℃,whereas the uncoated CIP had an oxidation starting temperature of approximately 250℃. Moreover, the largest oxidation rate temperature of CIP@TiO_(2) increased to around 550℃. This work opens up a novel strategy for the production of high-performance EMW absorbers via structural design.

关键词： carbonyl iron@titanium dioxide electromagnetic-wave absorption impedance matching oxidation resistance

Laser manufacturing of spatial resolution approaching quantum limit

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang Hong-Hua Fang zhen-Ze Li Dan Wang Hong-bo sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size ofboron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Research status and perspectives of MXene-based materials for aqueous zinc-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 1867-1885页

作者： Xiao-Yu Wang Qi-Hang Yang Xin-Yan Meng Meng-Meng zhen zhen-Zhong Hu bo-Xiong Shen School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300071China

Aqueous zinc-ion batteries(AZIBs)as green battery systems have attracted widespread attention in large-scale electrochemical energy storage devices,owing to their high safety,abundant Zn materials,high theoretica specific capacity and low redox *** there are some thorny issues in AZIBs that hinder their practical application,such as low intrinsic electron conductivity,slow ion migration kinetics,zinc dendrites and side ***-based materials with superior conductivity,large polar surface and abundant active sites can simultaneously serve as cathode materials,electrolyte additive and protection layer of anode to regulate redox reactions of *** various materials have been used to improve electrochemical performances of AZIBs there is a lack of in-depth discussion on the regulation mechanism of MXene-based materials for *** this review,we elaborate the research progress of MXenebased materials in AZIBs,including their application in cathode materials and inhibition of zinc *** the future prospects and development directions of MXenebased materials that may improve performance of AZIBs are prospected.

关键词： MXene Aqueous zinc-ion batteries Composite materials Zinc dendrites

superconducting,Topological,and Transport Properties of Kagome Metals CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)

在线全文

学校读者我要写书评

暂无评论

Research 2024年第2期2023卷 753-762页

作者： Xin-Wei Yi zheng-Wei Liao Jing-Yang You bo Gu Gang su School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Faculty of ScienceNational University of Singapore117551Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China

The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological ***_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with *** this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles *** superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 *** subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing ***,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through *** can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across ***,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density ***,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at *** work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.

关键词： doping superconductivity conductivity