Synergistic effect of heterogeneous single atoms and clusters for improved catalytic performance

Electrocatalytic water splitting provides an efficient method for the production of hydrogen.In electrocatalytic water splitting,the oxygen evolution reaction(OER)involves a kinetically sluggish four-electron transfer process,which limits the efficiency of electrocatalytic water splitting.Therefore,it is urgent to develop highly active OER catalysts to accelerate reaction kinetics.Coupling single atoms and clusters in one system is an innovative approach for developing efficient catalysts that can synergistically optimize the adsorption and configuration of intermediates and improve catalytic activity.However,research in this area is still scarce.Herein,we constructed a heterogeneous single-atom cluster system by anchoring Ir single atoms and Co clusters on the surface of Ni(OH)_(2)nanosheets.Ir single atoms and Co clusters synergistically improved the catalytic activity toward the OER.Specifically,Co_(n)Ir_(1)/Ni(OH)_(2)required an overpotential of 255 mV at a current density of 10 mA·cm^(−2),which was 60 mV and 67 mV lower than those of Co_(n)/Ni(OH)_(2)and Ir1/Ni(OH)_(2),respectively.The turnover frequency of Co_(n)Ir_(1)/Ni(OH)_(2)was 0.49 s^(−1),which was 4.9 times greater than that of Co_(n)/Ni(OH)_(2)at an overpotential of 300 mV.

密码算法在同步数据触发体系结构上的实现

研究了同步数据触发体系结构(SDTA)在密码处理中的应用。SDTA是一种基于数据传输触发的体系结构,与传统的操作触发体系结构相比具有更好的灵活性。性能测试的结果表明密码算法和单向散列算法在SDTA结构上获得了较好的性能。

Co-Design of Monolithically Integrated Photo-Detector and Optical-Receiver

A behavioral model of the photodiode is presented.The model describes the relationship between photocurrent and incident optical power,and it also illustrates the impact of the reverse bias to the variation of the junction capacitance.According to this model,the photodiode and a CMOS receiver circuit are simulated and designed simultaneously under a universal circuit simulation environment.

A General Study of the Number of Assembly Configurations for Multi-Circuit Planar Linkages

This paper presents a general approach for determining the configuration number for any linkage: A kinematic cham (KC) can be divided into some basic kinematic chains (BKCs) and driving joints; there are only 33 kinds of BKCs with υ =1-4 independent loop, containing only R (revolute) joints and their configuration numbers are given; the configuration number of a KC equals to the multiplication of the configuration numbers of BKCs contained in the KC.

优化方法,提高小学英语词汇教学有效性

小学英语教学中,同汇教学部分是重点,同时也是难点。小学生对于英语同汇感觉枯燥乏味,如何在课堂教学过程中,使得同汇教学趋于直观性,使枯燥的同汇教学趣味化,并使同汇教学置于特定的语境中,彰显整体性,是我们需要关注的问题。本文主要针对小学英语同汇教学进行分析和阐述,并且提出相关改进策略。

Hardware Optimization Technique of Full-Customized HW/SW Co-Design

The hardware optimization technique of mono similarity system generation is presented based on hardware/software(HW/SW) co design.First,the coarse structure of sub graphs' matching based on full customized HW/SW co design is put forward.Then,a universal sub graphs' combination method is discussed.Next,a more advanced vertexes' compression algorithm based on sub graphs' combination method is discussed with great emphasis.Experiments are done successfully with perfect results verifying all the formulas and the methods above.

Singlet oxygen synergistic surface-adsorbed hydroxyl radicals for phenol degradation in CoP catalytic photo-Fenton

In recent years,there have been numerous studies on Fenton or Fenton-like reactions mediated by nonfree radicals such as singlet oxygen(1O_(2));however,there are few studies on the synergistic effect of 1O_(2) and free radicals on the degradation of organic molecules,such as phenol in Fenton reaction.In this study,a cocatalyst,CoP,commonly used in photocatalysis was synthesized using a simple two-step method,and a CoP/Fe^(2+)/AM1.5 system was constructed by introducing Fe^(2+)and simulated sunlight(AM1.5)irradiation.The newly constructed CoP/Fe^(2+)/AM1.5 system could effectively degrade various organic pollutants,including dyes,phenols,and antibiotics.Radical quenching experiments and electron paramagnetic resonance detection confirmed that there were three reactive oxygen species(ROS)in the CoP/Fe^(2+)/AM1.5 system,including·OH_(ads),·O_(2)^(-),and 1O_(2).Further,combined with the liquid chromatogram of phenol,its intermediate products,and the fluorescence diagram of o-hydroxybenzoic acid,it can be concluded that a synergistic effect exists between 1O_(2) and the surface-adsorbed·OH_(ads) in the CoP/Fe^(2+)/AM1.5 system.The controllable formation of surface 1O_(2) and·OH_(ads) was achieved through the oxidation(Co^(3+))and reduction(Pδ−)centers exposed on the CoP surface,and the synergistic effect between them results in phenol’s hydroxylation,ring-opening,and degradation.The study of this new mechanism provides a new perspective for revealing the surface interface reaction between ROS and organic pollutants.

Divisible Semiring Congruences on Distributive Semiring

In this paper, we describe all the divisible semiring congruences on a distributive semiring S and also establish a one_to_one, inclusion_preserving mapping from the set of full, closed, self_conjagate, ideal subsemirings of S to the set of all divisible semiring congruences on S.

Hyperchaos behaviors and chaos synchronization of two unidirectional coupled simplified Lorenz systems

To design a hyperchaotic generator and apply chaos into secure communication, a linear unidirectional coupling control is applied to two identical simplified Lorenz systems. The dynamical evolution process of the coupled system is investigated with variations of the system parameter and coupling coefficients. Particularly, the influence of coupling strength on dynamics of the coupled system is analyzed in detail. The range of the coupling strength in which the coupled system can generate hyperchaos or realize synchronization is determined, including phase portraits, Lyapunov exponents, and Poincare section. And the critical value of the system parameter between hyperchaos and synchronization is also found with fixed coupled strength. In addition, abundant dynamical behaviors such as four-wing hyperchaotic, two-wing chaotic, single-wing coexisting attractors and periodic orbits are observed and chaos synchronization error curves are also drawn by varying system parameter c. Numerical simulations are implemented to verify the results of these investigations.

Single-Proton Pickup Reaction of the Halo Nucleus ^6He on a ^9Be Target at 25 MeV/nucleon

The inclusive differential cross sections of the ^7 Li nucleus in a reaction induced by ^6He on a ^9Be target are measured at an incident energy of 25 MeV/nucleon. Finite-range distorted-wave Born approximation calculations suggest that these ^7 Li particles are formed in a direct single-proton pickup reaction ^9Be（^6He,^7 Li）^8Li. The experimental data can be well reproduced by taking into account of the contributions of both the ground states and the first excited states of ^7Li and ^8Li.

A Equivalent Definition of Radical Property

This paper study the radical propertys in the sence of Amitsut and Kurosh from reference[1].

Elastoplastic solutions for single piles under combined vertical and lateral loads

In order to improve the reliability of the design and calculation of single piles under the combined vertical and lateral loads, the solutions were presented based on the subgrade reaction method, in which the ultimate soil resistance was considered and the coefficient of subgrade reaction was assumed to be a constant. The corresponding computational program was developed using FORTRAN language. A comparison between the obtained solutions and the model test results was made to show the validity of the obtained solutions. The calculation results indicate that both the maximum lateral displacement and bending moment increase with the increase of the vertical and lateral loads and the pile length above ground, while decrease as the pile stiffness, the coefficient of subgrade reaction and the yielding displacement of soil increase. It is also shown that the pile head condition controls the pile responses and the vertical load may cause the instability problem to the pile. In general, the proposed method can be employed to calculate the pile responses independent of the magnitude of the pile deflection.

Partial Orders on Right Inverse Semigroups

It is well known that there exists the smallest inverse semigroup congruence on an orthodox semigroup. We denote by Y the smallest inverse semigroup congruence on an orthodox semigroup. Let S be a right inverse semigroup. We construct partial orders on S by some kind of its subsemigroups and uncover that partial orders on S have close contact with partial orders on S/Y.

Research on the structure design of double eccentric coaxial spherical robot

The paper design a double eccentric mass driven spherical robot, the ball is also subject to eccentric force and inertia force that generate by internal drive units in movement. Due to the unique spherical shell, the robot in the dynamic state transition process, Friction cannot offset the robot motion state change due to internal driving motion error of small units. In order to make linear movement of the spherical robot that can smooth start, stop and speed control, the paper design a method for linear motion driven spherical robot with double eccentric mass control. The improved driving eccentric mass of robot total mass ratio is larger, that can provide the eccentric torque and inertia moment more, the robot has higher motion velocity.

Approach to Generalized Synchronization with Application to Chaos-Based Secure Communication

A constructive theorem is established for generalized synchronization (GS) related to C1 diffeomorphic transformations of unidirectionally coupled dynamical arrays. The theorem provides some interpretations about the underlying mechanism of various GS phenomena in nature. As a direct application of the theorem, a chaos-based secure Internet communication scheme is proposed. Moreover, a cellular neural network (CNN) of Chen's chaotic circuits with GS property is designed and studied. Numerical simulation shows that this Chen's CNN has high security and is fast and reliable for secure Internet communications.

Drift Intermittent Synchronization and Controllability in a Simple Model

A simple model of three coupled oscillators as an approximation of main modes behaviors in a spatial extended system is proposed. Multi-looping generalized synchronization and drift intermittent lag phase synchronization phenomena are found in this simple model. For a certain of parameters in which chaotic-like intermittent behavior exhibit the amplitudes and phases of three modes are controlled to be synchronized states via coupling them with an external periodic mode.

No association between phosphatase and tensin homolog genetic polymorphisms and colon cancer

AIM: To investigate the association between single nucleotide polymorphisms (SNPs) in the phosphatase and tensin homolog (PTEN) tumor suppressor gene and risk of colon cancer. METHODS: We utilized a population-based casecontrol study of incident colon cancer individuals (n= 421) and controls (n = 483) aged ≥ 30 years to conduct a comprehensive tagSNP association analysis of the PTEN gene. RESULTS: None of the PTEN SNPs were statistically significantly associated with colon cancer when controlled for age, gender, and race, or when additionally adjusted for other known risk factors (P > 0.05). Haplotype analyses similarly showed no association between the PTEN gene and colon cancer. CONCLUSION: Our study does not support PTEN as a colon cancer susceptibility gene.

Digital Communication Using Multi-mode Chaotic Lasers

The digital communication in a system of two multi-mode solid state chaotic lasers is investigated theoretically. If the usual method working well in a single-mode laser system is applied to a multi-mode laser system, the memory effect of the two nearest digits can cause high rate of mistakes when the digits are decoded through the subtraction of receiver output from the transmittal. By introducing the deviations of two nearest maximum and minimum fluctuationsof the signal to decode the digit, the message can be decoded correctly. Also, this communication method does not critically depend on the quality of the chaotic synchronization of the two multi-mode lasers.

GHz band frequency hopping PLL-based frequency synthesizers

In this paper we describe a full-integrated circuit containing all building blocks of a completed PLL-based synthesizer except for low pass filter（LPF）. The frequency synthesizer is designed for a frequency hopping （FH） transceiver operating up to 1.5 GHz as a local oscillator. The architecture of Voltage Controlled Oscillator （VCO） is optimized to get better performance, and a phase noise of -111.85-dBc/Hz @ 1 MHz and a tuning range of 250 MHz are gained at a centre frequency of 1.35 GHz. A novel Dual-Modulus Prescaler（DMP） is designed to achieve a very low jitter and a lower power. The settling time of PLL is 80 μs while the reference frequency is 400 KHz.This monolithic frequency synthesizer is to integrate all main building blocks of PLL except for the low pass filter, with a maximum VCO output frequency of 1.5 GHz, and is fabricated with a 0.18 μm mixed signal CMOS process. Low power dissipation, low phase noise, large tuning range and fast settling time are gained in this design.

Spin Parity Effect on Magnetic Relaxation by Quantum Tunneling in Nanomagnets

Spin parity effect on magnetic relaxation by quantum tunneling in the biaxial spin model is studied by taking into account the transverse local stray field. It is shown that the square root time dependence in the even resonance occurs in the presence of a distribution of transverse anisotropic parameters, while the odd resonance always shows exponential relaxation. Magnetic relaxation under a sweeping field is also studied. The variation of the relaxation curve with the increasing distribution width of the local stray field for even resonance is qualitatively different from that of the odd resonance. The theoretical result on even resonance is in agreement with experimental results on Fe8 system, while the prediction for odd resonance awaits the experimental verification.