摘要：Various designed circuits for multiple-valued all-optical arithmetic are demonstrated. The terahertz-optical-asymmetric-demultiplexer (TOAD) switch is used as the basic structure unit in the proposed circuits due to its compact size, thermal stability, and low power operation. The designs of trinary and quaternary signed-digit numbers based adders are presented using different polarized states of light. These proposed polarization-encoded based adders use much less switches and their speeds are higher than the intensity-encoded counterparts. Further, it will be shown that one of the proposed trinary signed-digit adders is twice as fast as a recently reported modified signed-digit adder.

摘要：The ternary cobalt-nickel-iron phosphide nanocubes (P-Co0.9Ni0.9Fe1.2 NCs) with high intrinsic activity, conductivity, defect concentration and optimized ratio have been realized through a facile phosphorization treatment using ternary cobalt-nickel-iron nanocubes of Prussian blue analogs (PBA) as a precursor. The scanning electron microscopy and transmission electron microscopy results show that the P-Co0.9Ni0.9Fe1.2 NCs maintain a cubic structure with a rough surface, implying the rich surface defects as exposed active sites. The thermal phosphorization of the ternary PBA precursor not only provids carbon doping but also leads to the in situ construction of surface defects on the NCs. The carbon doping from the PBA precursor lowers the charge transfer resistance and optimizes the electronic transformation. The synergistic effect among the ternary metal ions and rich defects contributes to the enhanced electrocatalytic performance . The P-Co0.9Ni0.9Fe1.2NCs achieve low overpotentials of -200.7 and 273.1 mV at a current density of 10 mA cm^-2 for the hydrogen evolution reaction and the oxygen evolution reaction, respectively. The potential of overall water splitting reaches 1.52 V at a current density of 10 mA cm^-2. The longterm stability of the electrocatalysts was also evaluated. This work provides a facile method to design efficient transitionmetal- based bifunctional electrocatalysts for overall water splitting.

摘要：The electronic metal-support interaction(EMSI)is one of most intriguing phenomena in heterogeneous *** this work,this subtle effect is clearly demonstrated by density functional theory(DFT)calculations of single Pt atom supported on vacancies in a boron nitride ***,the relation between the EMSI and the performance of Pt in propane direct dehydrogenation(PDH)is investigated in *** charge state and partial density of states of single Pt atom show distinct features at different anchoring positions,such as boron and nitrogen vacancies(Bvac and Nvac,respectively).Single Pt atom become positively and negatively charged on Bvac and Nvac,***,the electronic structure of Pt can be adjusted by rational deposition on the ***,Pt atoms in different charge states have been shown to have different catalytic abilities in *** DFT calculations reveal that Pt atoms on Bvac(Pt-Bvac)have much higher reactivity towards reactant/product adsorption and C–H bond activation than Pt supported on Nvac(Pt-Nvac),with larger adsorption energy and lower barrier along the reaction ***,the high reactivity of Pt-Bvac also hinders propene desorption,which could lead to unwanted deep ***,the results obtained herein suggest that a balanced reactivity for C–H activation in propane and propene desorption is required to achieve optimum *** on this descriptor,a single Pt atom on a nitrogen vacancy is considered an effective catalyst for ***,the deep dehydrogenation of the formed propene is significantly suppressed,owing to the large barrier on *** current work demonstrates that the catalytic properties of supported single Pt atoms can be tuned by rationally depositing them on a boron nitride nanosheet and highlights the great potential of single-atom catalysis in the PDH reaction.

摘要：The structure of multiphase flow helico-axial pump＇s rotor and how to model the rotor, especially the blades of the rotor, based on the Solidworks software. More important, the principle of the blade design is mainly introduced. Under the guide of the principle, the 3D coordinates of the blade data points can be got by matlab programming. In the paper, the design step and the modeling step are particularly described through a concrete example.

摘要：To solve the problem of low efficiency in pipe routing design, an improved genetic algorithm based approach is proposed. To present this approach, the paper mainly describes a generation method of nodes considering the safety distance of pipes and the directional constraints at terminals, the definition of a double coding technique, the collision detection method, the concept of energy and the definition of fitness functions. The similarity detection is introduced to prevent close breeding in the crossover operator, the selection pressure is controlled according to the evolution situation and a heuristic mutation method is used to boost the evolution. Simulation case shows that this approach is more practical and can satisfy different design requirements by changing algorithm parameters.

摘要：A reasonable design strategy to improve the utilization of noble metal electrocatalysts for the hydrogen evolution reaction(HER)is crucial to simplify the process flow and accelerate the future renewable energy ***,abundant defects were created on 2.4-nm Ru nanoparticles to achieve unprecedently high mass-specific reactivity in harsh acidic and alkaline *** obtained defect-enriched Ru(DR-Ru)exhibits an ultrahigh HER turnover frequency of16.4 s^(-1)with a 100-mV overpotential in alkaline media,and it also retains an excellent value of 20.6 s^(-1)in acidic media;these results are superior to those reported for other Ru ***,a record-low loading of 2.5μg cm^(-2)for the DR-Ru catalysts and low overpotentials of 28.2 and 25.1 mV at10 mA cm^(-2)can be realized in alkaline and acidic media,***,the less coordinated Ru surface sites and partial lattice oxygen introduction weaken the bonding between H and DR-Ru catalysts,facilitate fast acidic HERkinetics and help dissociate the water molecule to overcome the major challenge of HER in alkaline electrolytes,leading to an activity comparable to that under acidic *** result provides a guideline for defect engineering on noble metal nanocatalysts to effectively improve the utilization of the catalysts and optimize reactivities.

摘要：Large-scale production of polyethylene in industry requires efficient elimination of the trace amount of acetylene ***,zeolite adsorption or the conversion of acetylene to ethylene via selective semi-hydrogenation on Pd catalysts is the commonly used *** this work,we investigate the reaction mechanisms of acetylene hydrogenation on defective graphene(DG)supported singleatom catalysts(SACs),M1/SV-G and M1/DV-G(M=Ni,Pd and Pt)using density functional theory(DFT),where SV-G and DV-G represent DG with single and double vacancies,*** is shown that the metal single-atoms(SAs)as well as their different coordination numbers both affect the activity and selectivity of the hydrogenation process.M1/DV-G provides better H2 dissociation ability than M1/SV-G,which accounts for the poor acetylene hydrogenation activity of M1/*** on the reaction barriers,Pt1/DV-G and Ni1/DV-G are better catalysts than other systems considered here,with Ni1/DV-G exhibiting high selectivity for the semi-hydrogenation product of *** results provide insights for the design of highly selective and noble-metal-free SACs for acetylene hydrogenation on carbon materials.

摘要：This study combined fault identification with a deep learning algorithm and applied a convolutional neural network(CNN)design based on an improved balanced crossentropy(BCE)loss function to address the low accuracy in the intelligent identification of seismic faults and the slow training speed of convolutional neural networks caused by unbalanced training sample *** network structure and optimal hyperparameters were determined by extracting feature maps layer by layer and by analyzing the results of seismic feature *** BCE loss function was used to add the parameter which is the ratio of nonfaults to the total sample sets,thereby changing the loss function to find the reference of the minimum weight parameter and adjusting the ratio of fault to nonfault *** method overcame the unbalanced number of sample sets and improved the iteration *** a brief training,the accuracy could reach more than 95%,and gradient descent was *** proposed method was applied to fault identification in an oilfield *** trained model can predict faults clearly,and the prediction results are basically consistent with an actual case,verifying the effectiveness and adaptability of the method.

摘要：The development of Tongchuan City,Shaanxi Province,located in the northwestern region of China,is restricted by water *** direct current resistivity and induced polarization sounding methods are typically applied in finding urban *** methods,however,are not effective due to their complicated topography and geological *** application practice shows that the audio magnetotelluric(AMT)method has a large depth of exploration,high work effi ciency,and high lateral *** investigate the distribution of groundwater resources,we deployed three audio-frequency magnetotelluric profiles in the city *** impedance tensor information of AMT data is obtained using *** data dimension analysis reveals that the two-dimensional structural features of the observation area are *** main structure of the observation area is about 45°northeast,as indicated by structural trend analysis.A shallow two-dimensional electrical profile of 1 km in Tongchuan City is obtained by two-dimensional nonlinear conjugate gradient ***,combined with regional geological information,the geological structure characteristics reflected by the electrical profile were obtained along with the detailed characteristics of water-rich structures in the *** infl uence of the structure on the groundwater distribution was analyzed,and the water-rich areas were identifi *** work contributes to the prospective development of Tongchuan City.

摘要：This paper falls into two parts. In the first part, the widely used analytical-empirical method of pavement design and evaluation is discussed and in the second part two simulation models are presented to predict the design of flexible pavement. Analytical results are compared with simulation models.