Vertically-aligned graphene flakes on nanoporous templates: morphology,thickness, and defect level control by pre-treatment

Various morphologies of the vertically-aligned graphene flakes were fabricated on the nanoporous templates treated with metal ions in solutions, as well as coated with a thin gold layer and activated in the low-temperature Ar plasma. The thickness and level of structural defects in the graphene flakes could be effectively controlled by a proper selection of the pre-treatment method. We have also demonstrated that various combinations of the flake thickness and defect levels can be obtained, and the morphology and density of the graphene pattern can be effectively controlled. The result obtained could be of interest for various applications requiring fabrication of large graphene networks with controllable properties.     

基于Agent的辩论谈判系统的协议研究

协议是谈判支持系统实现的基本条件之一。依据经典的BDI（信念、愿望、意图）理论和已有的协议,将人类辩论思想融入,给出了协议的基本语言和逻辑框架,提出了相应的状态转换图,对状态转换图中的推理规则进行了详细阐述,从而构建了更加完整的基于Agent的辩论谈判系统协议。最后结合已有的策略和模型,以系统实现的方式对协议的合理性和有效性进行了验证,并指出了下一步研究方向。     

单一河口坝砂体规模的定量表征

以胜坨油田沙二段 8 砂组为例,综合应用水槽模拟实验和现代沉积的测量结果对辫状河三角洲河口坝内部构型进行了深入分析,并重点对河口坝长宽比定量规模进行了研究。 水槽模拟实验统计表明,模拟的研究区河口坝长 45～210 cm ,宽 30～150 cm ,长度与宽度具有较好的相关性。 现代沉积的测量结果也说明了河口坝的长度与宽度具有较好的相关性。 综合水槽模拟实验与现代沉积测量的结果,建立了研究区单一河口坝长宽比经验公式。 利用该公式可以指导研究区精细河口坝构型解剖,辅助判断单一河口坝边界,为建立三角洲前缘河口坝精细三维地质模型提供了依据。     

Identification of Plasma Boundary and Position for HL-2A Tokamak

Using the virtual-case principle, the plasma boundary, the plasma current center, and the x-point are identified for the HL-2A tokamak. The plasma current is represented by the current center and the virtual multipole moments which produce a magnetic flux in a form of polynomial. Adaptive parameters in the polynomial are determined by the least-square fit of the poloidal magnetic fields. The measurement of the magnetic field is performed using pick-up coils. The virtual-case principle is applied outside the plasma boundary. The virtual-case currents decide the position of the current center and produce a negative confinement magnetic field inside the plasma and the magnetic field generated by the plasma current outside the plasma boundary. The convergence is fast enough to get a picture between the sequent shots. The configuration reconstructed is in good agreement with the TV image taken by camera with a tangential view.     

一种用于蓝牙系统的延迟锁相正交信号发生器

提出了一种延迟锁相结构的正交信号发生器 ,用于蓝牙的射频信号收发电路。介绍的延迟锁相环路结构使电路性能具有良好的工艺变化不相关性 ,在很宽的频带范围内均可获得高性能的正交信号。电路采用单层多晶硅、四层金属、0 .3 5 μm CMOS数字工艺实现 ,仿真结果表明 :电路稳定工作在 2 .45 GHz频率下 ,在 1 40 MHz的输入信号频率变化范围内 ,输出的正交信号相位偏差低于 1°,幅度偏差小于 5 %。电路主要由有源器件构成 ,面积小     

Phosphate removal from aqueous solutions using raw and activated red mud and fly ash

The effect of acidification and heat treatment of raw red mud (RM) and fly ash (FA) on the sorption of phosphate was studied in parallel experiments. The result shows that a higher efficiency of phosphate removal was acquired by the activated samples than by the raw ones. The sample prepared by using the RM stirred with 0.25 M HCl for 2h (RM0.25), as well as another sample prepared by heating the RM at 700 degrees C for 2h (RM700), registered the maximum removal of phosphate (99% removal of phosphate). This occurred when they were used in the phosphate sorption studies conducted at pH 7.0 and 25 degrees C with the initial PO(4)(3-) concentration of 155 mg P/l. The FA samples treated in the same way described above can achieve 7.0 and 8.2 mg P/l phosphate removal for FA0.25 and FA700 respectively, corresponding to 45.2% and 52.9% removal. The activated materials performed higher phosphate removal over broader pH range compared with the raw ones. The influences of various factors, such as initial pH and initial phosphate concentration on the sorption capacity were also studied in batch equilibration technique. Solution pH significantly influenced the sorption. Each sample achieved the maximal removal of phosphate at pH 7.0. The amount of phosphate removal increased with the solute concentration. The Freundlich and Langmuir models were used to simulate the sorption equilibrium. The results indicate that the Langmuir model has a better correlation with the experimental data than the Freundlich model.     

Hierarchical Optimization of Network Resource for Heterogeneous Service in Cloud Scenarios

With limited homogeneous and heterogeneous resources in a cloud computing system, it is not feasible to successively expand network infrastructure to adequately support the rapid growth in the cloud service. In this paper, an approach for optimal transmission of hierarchical network for heterogeneous service in Cloud Scenarios was presented. Initially, the theoretical optimal transmission model of a common network was transformed into the hierarchical network with the upper and lower optimization transmission model. Furthermore, the computation simplification and engineering transformation were presented for an approximation method at the low cost of computational complexity. In the final section, the average delay in the engineering method shows its influence on the capability of access for common nodes.     

Influence of polyethylene glycol molecular weight on the anticancer drug delivery of pH-sensitive polymeric micelle

Polyethylene glycol (PEG) and pH-sensitive polymers have been widely utilized in anticancer drug delivery systems due to their characteristics of prolonging circulation time and tumor-responsive drug release. However, the effect of PEG molecular weight on the delivery of anticancer drug-encapsulating pH-sensitive polymer micelles has been poorly studied. Therefore, a simple method was used to prepare pH-sensitive doxorubicin (DOX)-loaded micelles (DOX/POD) based on polyethylene glycol-2-(octadecyloxy)-1, 3-dioxan-5-amine (POD) polymers, and the influence of PEG molecular weights (1 K, 2 K, and 5 K) on in vitro drug release and antitumor effect was further studied. Interestingly, as the molecular weight increased, the release amount of DOX was augmented. While the cytotoxicity and cellular uptake were increased, the molecular weight was decreased. It is reasonable to speculate that the high molecular weight of PEG may promote the dissolution rate of DOX, and their micelles with uncompact structure are being prone to disassembly in an acid environment. However, the low molecular weight of PEG may contribute to the formation of compact POD micelles, which make it easier to be uptaken by tumor cells resulting in the enhanced antitumor effect. Taken together, the results indicate that pH-sensitive POD micelles with low molecular weight can achieve the efficient delivery of drugs, and PEG molecular weight in pH-sensitive nanocarriers may influence the antitumor effect. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47854.     

特殊函数旋转变压器基本公式探讨

由谐波绕组构成的特殊函数旋转变转压器，必须考虑齿谐波和气隙磁场衰减的影响．本文分析了上述因素，并获得了这种电机的基本方程式，为进一步提高这种电机的精度提供了理论依据。