Cutting and Welding of Nanomaterials with an Electron Beam

1 Results Scanning tunneling microscope and atomic force microscope have been applied to manipulate individual atoms or clusters on a clean surface.Focused ion beam technique is routinely used to cut materials down to sub-100 nm dimension.However,in between the atomic and the sub-100 nm scales,i.e.,at the nanometer scale,to date there is no well-established physical modification technique.Here we demonstrate that localized,impurity-free nano-welding and nano-cutting techniques with a high-intensity electron beam (HIEM) have a great potential for the fabrication of nanodevices.It is known that an intense electron beam causes various inelastic scattering processes in a target specimen that create heating,amorphization,ablation effects,and,when the intensity is high enough,some nonlinear effects such as plasma formation at the specimen surface.We will show that a HIEB with an intensity of 106 A/cm2 can be applied to create holes,gaps,and other patterns of nanometer dimensions on a single semiconducting or metallic nanowire[1].In particular,the hole-formation process on silicon nanowires under a HIEM will be discussed in detail.We will also show that an electron beam with slightly weaker intensities can be used to weld individual nanowires,forming metal-to-metal or metal-to-semiconductor nanowire junctions.This can be applied to reduce contact resistance between metallic nanowires and leads[2],and,e.g.,to fabricate nano-scale thermal couples.     

Study of GaAIAs／GaAs Planar Lightwave Filters

Based on the theory of four-port resonator filters, the characteristics of four kinds of filters with single race-track, dual race-track, rectangular and MMI resonators respectively were numerically simulated by utilizing two-dimensional FDTD method. The relationship between the number of cascade resonators and the filtering features was also analyzed. A kind of narrow-band filters with four cascade resonators implemented on GaA1As/GaAs planar lightwave circuits were designed and fabricated. The measurement result shows that the half-width of such filters is about 10nm, which coincides well with the numeric computation.     

AGVs Dispatching Using Multiple Cooperative Learning Agents

AGVs dispatching,one of the hot problems in FMS, has attracted widespread inte rest in recent years. It is hard to dynamically schedule AGVs with pre-designed rule because of the uncertainty and dynamic nature of AGVs dispatching progress,so the AGVs system in this paper is treated as a cooperative learning mul tiag ent system, in which each agent adopts multilevel decision method, which includes two level decisions:the option level and the action level.On the option level,an agent learns a policy to execute a subtask with the best resp onse to the other AGVs'current options. On the action level,an agent learns an optimal policy of actions for achieving his planned option.The method is applied to a AGVs'dispatching simulation,and the performance of the AGVs system bas ed on this method is verified.     

ZnO and MnO2 Doped PbTiO3 Ceramics Prepared by Sol-gel Method

ZnO and MnO2-doped PbTiO3 nanometer powders have been prepared by using titanium butoxide (Ti(OC4H9)4) and lead acetate (Pb(Ac)2.3H2O) as starting materials, acetic acid (HAc) and methanol (CH3OH) as catalyst and solvent, respectively, and Zn(Ac)2 and Mn(NO3)2 as dopants. High density and crack-free PbTiO3 ceramics were obtained. Electrical measurement indicates that the ceramics has lower dielectric constant, dielectric loss, and especially low surrounding moisture effect.     

An Optimal Portfolio Model with Transaction Cost

In this paper, a convex programming model for portfolio select with trans- action costs was present, we proved the existence condition of optimal solution, and gave a simple example to the optimal solution.     

Separation and Purification of Thrombin-like Enzymes by Affinity Adsorbents

An affinity adsorbent, benzamidineSepharose 4B, was used to separate and purify thrombinlike enzymes. The paminobenzamidine as a specific ligand was coupled to the matrix-Sepharose 4B. The recombinant thrombinlike enzyme-defibrase was used as a model in order to evaluate the efficiency of this biospecific affinity adsorbent. The homogeneity of the enzyme preparation was comfirmed as one band on sodium dodecyl sulfatepolyacrylamide gel electrophoresis.     

What is the most important in development of theory of mind?—The roles of EF, verbal and arithmetic ability, and working memory

The present study examined the contributions of age, verbal ability, arithmetic ability, working memory, and executive function (EF) to the development of theory of mind (ToM). The results showed that age, arithmetic ability, working memory, and EF were significant predictors of the development of ToM, while verbal ability did not. And results from the hierarchical regression analysis suggested that, compared to EF, arithmetic ability and working memory were more important in predicting the development of ToM.     

Cloning of GF14 Gene from the Bulbs of Fritillaria crrishoa

GF14 widely occurs in plant species functioning as a regulatory protein in cell signal transdution,including monoamine synthesis,exocytosis and cell cycle regulation.A partial sequence,413bp in length,is cloned from the bulbs of F.crrihosa by means of RT-CPR technique.Sequence alignment with the BLAST program shows that it is highly similar to GF14 gene.A new full-length cDNA,1133bp,is obtained by RACE techniques,It contains a major open reading frame of 262 amino acids,5‘ and 3‘untranslated regions and a long Poly(A) tail,Sequence analysis of deduced GF14 protein from F.crrihosa indicates several conserved motifs of GF14 protiens are also found in sequence of GF14 protein of F.crrihosa.     

Study on Integrated Quality Assurance System in CIMS

Integrated Quality Assurance System (IQAS) is an important part of CIMS.This paper introduces the architecture of IQAS,elaborates the philosophy of quality assurance and quality control in CIMS.A type of function model is proposed.Meanwhile, details of the model are described.