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Efficient adjustment of product selectivity using controllable Pd nanoparticles in nitroarene hydrogenation

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Particuology 2020年第1期18卷 13-18页

作者： Jian Zhang Liang Wang Fang Chen Feng-Shou Xiao key laboratory of applied Chemistry of Zhejiang province and Department of Chemistry Zhejiang UniversityHangzhou 310028China

Product selectivity adjustment is a much-studied topic in mesoscience that is critical for industrial processes and strongly related to reaction intermediates formed by interactions between catalytic active sites and ***,we report efficient adjustment of the product selectivity in the hydrogenation of substituted nitroarenes via rational reaction intermediates achieved using controllable Pd *** nanoparticles fixed within zeolite Beta crystals(Pd@Beta)afforded rational Pd-NO2 interactions,in which the Pd nanoparticle-adsorbed substituted nitroarenes,such as nitrobenzaldehyde,were reasonably hydrogenated into the corresponding ***,for Pd nanoparticles supported on the external surfaces of zeolite beta crystals,various side products were obtained owing to the coexistence of Pd-NO2 and Pd-C=O *** Pd nanoparticles were artificially controlled in various positions in a fixed-bed reactor,the product selectivity was significantly *** results demonstrate the importance of molecular adsorption and diffusion processes in adjusting product selectivity in catalytic reactions.

关键词： Product selectivity Nitroarene hydrogenation Pd nanoparticles Zeolite crystals

PHASE RETRIEVAL OF TIME-LIMITED SIGNALS

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Acta Mathematica Scientia 2010年第1期30卷 39-46页

作者：付应雄李落清 Hubei key laboratory of applied mathematics Hubei University Faculty of mathematics and Computer Science Hubei University

The problem of reconstructing a signalφ（x） from its magnitude ｜φ（x）] isof considerable interest to engineers and physicists. This article concerns the problem of determining a time-limited signal f with period 2π when ｜f（eix）l is known for x∈[-π,π]. It is shown that the conditions ｜g（eix）｜ = ｜f（eix）｜ and ｜g（ci（x＋b）） -g（eix）｜ =f（ei（x＋b）） - f（eix）｜, b ≠ 27π, together imply that either g = wf or g = v f, where both w and v have period b. Furthermore, if b/2π is irrational then the functions w and v b is rational then w takes the form reduce to some constants c1 and c2, respectively; ifb/2π is rational then w takes the form w=elexB1（e1x）B2（elx）and v takes the form ei（x2πN/b＋a）B1（elx）B2（elx）,where B1 and B2 are Blaschke products.

关键词： phase retrieval time-limited signal Blaschke product Hardy space on theunit circle

Spatial analysis of carbon storage density of mid-subtropical forests using geostatistics： a case study in Jiangle County, southeast China

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Acta Geochimica 2018年第1期37卷 90-101页

作者： Zhuo Lin Lin Chao Chengzhen Wu Wei Hong Tao Hong Xisheng Hu College of Forestry Fujian Agriculture and Forestry University Fuzhou Fujian Province China fujian Institute of Scientific and Technological Information Fuzhou 350001 Fujian ProvinceChina Institute of applied Ecology Chinese Academy of ScienceKey Laboratory of Forest Ecology and ManagementShenyang Liaoning Province China university of Chinese Academy of Science Beijing China Department of Ecology and Resource Engineering Wuyi UniversityNanping 354300 Fujian Province China College of Transportation and Civil Engineering Fujian Agriculture and Forestry University FuzhouFujian Province China

The mid-subtropical forest is one of the biggest sections of subtropical forest in China and plays a vital role in mitigating climate change by sequestering *** have examined carbon storage density(CSD) distribution in temperate forests. However, our knowledge of CSD in subtropical forests is limited. In this study, Jiangle County was selected as a study case to explore geographic variation in CSD. A spatial heterogeneity analysis by semivariogram revealed that CSD varied at less than the mesoscale(approximately 2000–3000 m). CSD distribution mapped using Kriging regression revealed an increasing trend in CSD from west to east of the study *** spatial autocorrelation analysis indicated that CSD was clustered at the village level(at 5% significance).Some areas with local spatial autocorrelation were detected by Anselin Local Moran's I and Getis-Ord G*. A geographically weighted regression model showed different impacts on the different areas for each determinant. Generally, diameter at breast height, tree height, and stand density had positive correlation with CSD in Jiangle County, but varied substantially in magnitude by *** contrast, coefficients of elevation and slope ranged from negative to positive. Based on these results, we propose certain measures to increase forest carbon storage,including increasing forested area, improving the quality of the current forests, and promoting reasonable forest management decisions and harvesting strategies. The established CSD model emphasizes the important role of midsubtropical forest in carbon sequestration and provides useful information for quantifying mid-subtropical forest carbon storage.

关键词： Carbon storage density Geostatistics Mid-subtropical forests Spatial autocorrelation Spatial heterogeneity

利用双向气相输运方法实现厘米级黑磷单晶片的高产量生长（英文）

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Science China Materials 2025年第1期 217-225页

作者：王思源陈程梁雅宁侯新刚王相懿董卓王俊勇江潮张凯 key laboratory of Semiconductor Display Materials and Chips & i-Lab Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences School of Nano Science and Technology University of Science and Technology of China MIIT key laboratory of Semiconductor Microstructure and Quantum Sensing and Department of Applied Physics Nanjing University of Science and Technology School of Materials Science and Engineering Shanghai University CAS key laboratory of Standardization and Measurement for Nanotechnology National Center for Nanoscience and Technology university of Chinese Academy of Sciences

黑磷凭借其高载流子迁移率、广泛可调的直接带隙及面内各向异性等优异的性质,被认为是一种极具潜力的二维半导体材料.尽管当前对黑磷已经进行了大量的研究,但制备大尺寸高质量的黑磷单晶仍然存在挑战.本文提出了双向气相输运（BVT）策略...

黑磷凭借其高载流子迁移率、广泛可调的直接带隙及面内各向异性等优异的性质,被认为是一种极具潜力的二维半导体材料.尽管当前对黑磷已经进行了大量的研究,但制备大尺寸高质量的黑磷单晶仍然存在挑战.本文提出了双向气相输运（BVT）策略,实现了每批次数十片厘米级黑磷单晶薄片的生长.通过一系列的结构和光谱表征,证明了其卓越的晶体质量和高纯度.所生长的黑磷单晶薄片具有光滑的解理面,能够轻松剥离成大面积的纳米片.基于此方法制备的黑磷场效应晶体管表现出优异的电学性能,包括高达1150 cm2V-1s-1的载流子迁移率和约106的电流开关比.此方法同样适用于黑磷的掺杂体系,如黑砷磷、黑硒磷和黑碲磷等.本文提出的高产量生长厘米级黑磷单晶薄片的策略将加速黑磷基电子和光电子学的研究与应用.

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Reversal of thermal rectification in one-dimensional nonlinear composite system

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Chinese Physics B 2014年第11期23卷 348-353页

作者：詹斯琦黄维清黄桂芳 Department of applied Physics key laboratory for Micro-Nano Physics and Technology of Hunan province Hunan University

Using nonequilibrium molecular dynamics simulations, a comprehensive study of the asymmetric heat conduction in the composite system consisting of the Frenkel-Kontorova （FK） model and Fermi-Pasta-Ulam （FPU） model is conducted. The calculated results show that in a larger system, the rectifying direction can be reversed only by adjusting the thermal bias. Moreover, the rectification reversal depends critically on the system size and the properties of the interface. The mechanisms of the two types of asymmetric heat conduction induced by nonlinearity are discussed. Considering the novel asymmetric heat conduction in the system, it may possess possible applications to manage the thermal rectification in situ directionally without re-building the structure.

关键词： thermal rectification reversal nonlinearity composite system

Reexamining Security of Improved Multiparty Quantum Secret Splitting and Quantum State Sharing

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Communications in Theoretical Physics 2010年第6期53卷 1059-1061页

作者：林崧 key laboratory of Network Security and Cryptography Fujian Normal University School of mathematics and Computer Science Fujian Normal University

In a recent letter [H.F. Wang, X. Ji, and S. Zhang, Phys. Lett. A 358 （2006） 11], an improvement of the multiparty quantum secret splitting and quantum state sharing protocol [F.G. Deng, et al., Phys. Lett. A 354 （2006） 190.] was presented. We study the security of the improved protocol and find that two or more dishonest participants may recover the secret from the dealer. Hence we further modify the improved protocol, which make it stand against this kind of attack.

关键词： quantum secret sharing entanglement swapping

Distributed Nash Equilibrium Seeking Over Random Graphs

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2193-2196页

作者： Ji Ma Jiayu Qiu Xiao Yu Weiyao Lan Department of Automation Xiamen Universityand the Key Laboratory of Control and Navigation(Xiamen University)Fujian Province UniversityXiamen 361005China IEEE Department of Automation Xiamen University and the Key Laboratory of Control and Navigation(Xiamen University)Fujian Province UniversityXiamen 361005China Innovation laboratory for Sciences and Technologies of Energy Materials of fujian province(IKKEM) Xiamen 361005China

Dear Editor,This letter is concerned with the distributed Nash equilibrium(NE)seeking in an N-player game over random graphs. We develop a distributed stochastic forward-backward(DSFB) algorithm based on local information exchange between agents. We prove that the DSFB algorithm can converge to an NE almost surely, and analyze the convergence rate of the proposed algorithm. Compared with the existing works on distributed NE seeking, the communication graph in this letter is supposed to be time-varying and stochastic, which makes the NE seeking algorithm more suitable for practical scenarios, but brings a great challenge in both the design and convergence analysis of the algorithm. Besides, by establishing a variational inequality on NE, we relax the co-coercivity or strong monotonicity assumption on the extended pseudo-gradient.

关键词： seeking letter stochastic

Endogenous Fe^(2+)-activated ROS nanoamplifier for esterase-responsive and photoacoustic imaging-monitored therapeutic improvement

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Nano Research 2022年第2期15卷 907-918页

作者： Sijin Xiang Zhongxiong Fan Ziehen Ye Tianbao Zhu Dao Shi Shefang Ye Zhenqing Hou Xiaolan Chen College of Chemistry and Chemical Engineering&College of Materials State Key Laboratory for Physical Chemistry of Solid SurfacesResearch Center for Nano-Preparation Technology of Fujian Province&Key Laboratory of Biomedical Engineering of Fujian ProvinceXiamen UniversityXiamen 361005China

Chemodynamic therapy(CDT)is well acknowledged as potent reactive oxygen species(ROS)-mediated anticancer ***,the study about labile iron pool(LIP)as endogenous ferrous catalyzer has paved the way for future CDT ***,limited H_(2)O_(2) expression,mild acidity,reduced glutathione(GSH)ablation of ROS,etc.,all require employing alternate peroxo-complex to achieve enhanced CDT *** a non-Fenton-type substrate,artesunate(ART)has been utilized as a source of free radicals through decomposition of endoperoxide bridges catalyzed by ferrous ions,nonetheless,the non-tumor-specific delivery,inferior pharmacokinetics,and hydrophobic nature minimize the efficacy of ART in physiological ***,we devise a PPA nanoamplifier by conjugating ART with PEG-functionalized Pd@Pt nanoplates(PP NPs)to form ester linkage,ensuring specific intratumoral esterase-responsive ART ***,the PPA nanoamplifier combines the in situ decomposition of ARTs endoperoxide bridges by Fe^(2+) to superoxide anions(O_(2)^(·-))and peroxidase(POD)-like enzymatic catalysis of endogenous H_(2)O_(2) by PP to hydroxyl radicals(*OH),thus achieving amplified ROS-mediated tumor ***,PPA displays GSH destruction potential,thereby protecting ROS from the cleavage by GSH *** addition,the strong absorption of PPA in near-infrared(NIR)region also endows PPA with photoacoustic property to realize imaging-guided *** short,by taking advantages of the high enrichment and esterase-responsive drug release at tumor sites,PPA amplified ROS signals via dual pathways,killing tumor cells in vitro are inhibiting tumor growth in vivo,thereby realizing high-efficiency non-Fenton *** believe our novel anti-tumor strategy based on PPA will broaden the future of ROS-mediated tumor-targeted therapy.

关键词： reactive oxygen species chemodynamic therapy non-Fenton tumor microenvironment drug delivery

Numerical analysis of cavitation within slanted axial-flow pump

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Journal of Hydrodynamics 2013年第5期25卷 663-672页

作者：张睿陈红勋 Shanghai Institute of applied mathematics and Mechanics Shanghai University Shanghai Institute of applied mathematics and Mechanics and Shanghai key laboratory of Mechanics in Energy Engineering Shanghai University

In this paper, the cavitating flow within a slanted axial-flow pump is numerically researched. The hydraulic and cavitation performance of the slanted axial-flow pump under different operation conditions are estimated. Compared with the experimental hydraulic performance curves, the numerical results show that the filter-based model is better than the standard k-ε model to predict the parameters of hydraulic performancE. In cavitation simulation, compared with the experimental results, the proposed numerical method has good predicting ability. Under different cavitation conditions, the internal cavitating flow fields within slanted axial-flow pump are investigated. Compared with flow visualization results, the major internal flow features can be effectively grasped. In order to explore the origin of the cavitation performance breakdown, the Boundary Vorticity Flux （BVF） is introduced to diagnose the cavitating flow fields. The analysis results indicate that the cavitation performance drop is relevant to the instability of cavitating flow on the blade suction surface.

关键词： slanted axial-flow pump cavitation filter-based model numerical simulation