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The electric energy data acquisition system is an important part of smart grid construction, and as well it is the essentail platform and core support of intelligent electricity service system. As the “neural network” of electric energy data acquisition system, the communication technology plays a vital role for improving the system performance. In this paper, we performed a comparative test associated with the application performance of electric energy data acquire solution, whilst considing both narrowband power line communication (PLC) and broadband PLC technologies. While comparing the test resuls in both laboratory ideal environment and comprehensive interference environment, it provides an important data support to master the performance of different PLC technologies in electric energy data acquisition system.

A novel polyacrylic acid /xanthan gum/bentonite superabsorbent polymer (SAP) was prepared through chemical crosslinking by a polymerization technique in a complete aqueous environment. This SAP was fabricated effectively by dispersing xanthan gum (XG) and bentonite in a monomeric solution, using N,N’-methylenebisacrylamide as crosslinker and ammonium persulfate as initiator. Fourier transform infrared (FTIR) spectral analysis showed that graft copolymerization reaction took place between acrylic acid (AA), XG and bentonite. The optimal process conditions of preparing SAP were investigated. Results showed that the relevant SAP had maximal salt-water absorption (98g/g) when mass ratio of m (bentonite):m (AA) was 5:1, m (ammonium persulfate):m (AA) was 1.75×10-4, m (N,N’-methylenebisacrylamide):m (AA) was 3×10-4, m (XG) :m (AA) was 1:5, the neutralization degree of AA was 75%. Bentonite can not only effectively increase water absorbency, but also improve water retention ability.

In this paper, we address a channel estimation scheme for power line communication systems based on compressed sensing techniques. With the properly designed pilot symbols, the received signals at the receiver can be reconstructed from a set of random projections, benefiting from a reduced sampling rate. Moreover, we propose a novel channel estimation structure for PLC systems, which can be applied for appropriate system design. Eventually, simulation results demonstrate that the proposed algorithm outperforms other algorithms and reduces the sample rate significantly.

The remote communication is an important part of electric energy data acquisition system. Currently, the electric energy data acquisition remote communication has these disadvantages such as high costs of GPRS rental , poor reliability and it’s hard to meet the demand of real-time fee control and other senior business. To solve these problems, this paper proposes a solution for electric energy data acquisition remote communication channel by using built fiber access network to combine with broadband power line carrier communication technology .This solution have achieved a good result through field pilot application and validated the feasibility of it.

This paper mainly introduces the assessment methods of bit error performance which can effect the sensitivity of the receiver in micro power wireless communication system,use simple Poisson distribution and binomial distribution to analyzes the quota such as FBR, BER and average bit error rate impact of the bit error performance. In order to enhance the accuracy and reliability of sensitivity test,we give a true random bit stream generator to improve the emission signal which is used to detect the error performance.

The electric energy data acquire system with full coverage of power user is the important component of the deployment of strong & smart grid. The low-voltage power line communication has become a mainstream technology in the construction of electric energy data acquire system in China. Micro-power wireless is a short-range, low-power, low complexity, low-cost wireless communication technology, which has the characteristics of large capacity, short delay and high stability. However, a single communication mode is hard to meet the requirement of full coverage of electric power user because the structure of distribution network is complicated. This paper proposes an integrated solution based on the PLC and micro-power wireless communication for electric energy data acquire network system, which achieved good results in the field, validate the feasibility of the solution.

The effects of the polysaccharide extracted from Tricholoma matsutake on the immune response of Sarcoma180 bearing mice were evaluated. Mice were treated with two doses of polysaccharideL-2(1,10mg/kgbodyweight) for 10 days. The concentration of tumor necrosis factor-alpha (TNF-α), interferon-2(IL-2) in mice serum and TNF-α mRNA expression were determined. The concentration of TNF-α in serum increased significantly in two doses groups compared to the model control group, but IL-2 not. The level of TNF-α mRNA transcription increased significantly in two doses groups to the model control group. Results of these studies demonstrated the polysaccharide significantly promoted TNF-α production, immunity potentiating and anti-tumor effects of the polysaccharide were associated with its potentiation of TNF-α mRNA expression at the transcriptional level.

3D human kinematic measurement system was adopted in this study , this study compared the kinematic characteristic between forehand and backhand serve in three types. Seven male badminton players participated in this study. After analyzing the captured images, this study come to the conclusion as follows: (a) there are significant difference between the backhand and the forehand serve,and there are no difference between difference serve types within both forehand and backhand during back swing phase, (b) there are significant difference between the backhand and the forehand serve, and there are significant difference between short serve, high serve, and drive serve within both forehand and backhand, (c) there are significant difference between the backhand and the forehand serve, and there are significant difference between short serve, high serve, and drive serve within both forehand and backhand.

Currently, micro-power wireless communication technology used in power user electrical energy data acquire system have some problems such as transport distance, power, data rate, antenna length, interaction (standard), deployment environment, stray radiation and so on. This paper proposed a micro-power wireless communication module which meets the State Grid Corporation of China Enterprise Standard Q/GDW 1374.3-2013 was designed by the author,and the key technology and major problems were researched and analyzed.

This paper introduces the power line carrier communication technology and switching power supply, and expounds the factors that affect the switching power supply for power line communication, analyzes how to solve the problem of switching power supply in power line communication, such as analysis of phase noise electromagnetic interference on the impact of switching power supply, and proposes measures to perfect the switching power supply.

In the micro-power wireless transmission of the electric system, positions among modes are relatively fixed, power business data is reported at specific time points, and time distribution presents great differences. Key technologies of IEEE802.15.4 MAC layer protocol is expounded, shortages of collision detection and CSMA/CA on power business support, etc. are discussed, self-adaptive low-power consumption CSMA/CA algorithm which is more suitable for business of the electric system are designed and improved, and the algorithm goes through simulation experiment against the business characteristics of micro-power wireless network of the electric system. The simulation result demonstrates the algorithm may be greatly adapted to changes of network traffic under a relatively fixed environment of network topology on the premise of low power consumption.

In this paper, viscous effects on hypersonic vehicle are investigated. Firstly, viscous aerodynamic is modeled based on reference temperature method, and viscous aerodynamic lift, drag and pitching moment are calculated by the model. And then, aerodynamic forces and elastic deformation are analyzed by comparing with viscous effects on/off. In final, considering the thermal choking condition, longitudinal velocity and attitude boundary values are discussed.

The aim was to research the antimicrobial effect of the extracts of Fruits of Herba Leonuri with different solvents on the common plant microbes. The bacteria cake method was used to study the antimicrobial capability of Fruits of Herba Leonuri. The extracts have anti-bacterial action on Rhixoctonia cerealis, Fusarium gram inearum, Rhizoctonia solani and Setosphaeria turcica, especially the extract from distilled water has the strongest anti-bacterial action on Rhixoctonia cerealis and Fusarium gram inearum, the extract from ether has the strongest anti-bacterial action on Fusarium gram inearum, the MIC all were 10 mg/ml The extracts had different antimicrobial effect when pH value was from 5 to 8. The extracts of Fruits of Herba Leonuri could inhibit the 4 pathogenic microorganism, and the antibacterial activity was affected by pH value greatly.

The microscopic morphological characteristics of main clay minerals in Zhangcun illite ores were studied by using high-resolution scanning electron microscopic (SEM) and image analysis technology. The results show that: (1) the illite generally appear as crooked scaly and foliated partly; (2) illite/smectite (I/S) mixed layered mineral are banding flake with filamentous edge mostly and cusp type flake partly; (3) pyrophyllite appear to be flake and tabular sheet forming hollow pipe; (4) serpentinite are obviously fine flake with wavy shape .

The aim of this study was to determine the procedure parameters, including drying, extracting and pH on the antioxidant activity and antioxidative compounds in Perilla frutescens leaves. The extraction of antioxidants from Perilla frutescens leaves is studied considering different drying and extracting procedures to investigate the selectivity of the process. The radical-scavenging activity (RSA) of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and the determination of the total phenolic content are applied to evaluate the antioxidant activity and antioxidative compounds of the Perilla frutescens leave extracts. The highest antioxidant activity is observed for the extract obtained by freeze drying, extracting by ultrasound with 80% methanol adjusted at pH 4.The antioxidant compound extraction yield was also the highest at these extraction conditions. The total phenol contents among the Perilla frutescens leave extracts produced by different drying procedures were similar, while the antioxidant activities were different This concluding that the amount of phenolic compounds extracted was similar but the type and probable structure of the phenolic changed during heat-drying procedure providing in this way. Our study showed that proper process technology could ultimately extract compounds potentially effective against diseases related to free radical oxidation.

To explore the effects of Perilla frutescens leaf total flavonoid (PFF) on regulating the serum level of lipids, enzymes of lipoprotein metabolism and antioxidation in the hyperlipidemia rats. 50 healthy SD rats were divided into 5 groups randomly according to the serum TC: hyperlipidemia model group, high dose group of PFF, medium dose group of PFF, low dose group of PFF, and lovastatin treatment positive control group. Serum lipoprotein level, lipoprotein lipase (LPL), hepatic lipase (HL),superoxide dismutase (SOD) and malondialdehyde (MDA) were tested after treated with corresponding drugs once per day for 4weeks. Compared with the model group, the levels of the serum TC, TG, LDL-C, and MDA decreased significantly, while HDL-C, LPL, HL and SOD increased significantly (P < 0.05 or P < 0.01). The lipid metabolic disorder in hyperlipidemia rats was improved notably through the treatment with PFF, indicating that the PFF plays an important role in decreasing lipids.

Effects of solvent types and extraction methods were investigated for effective recovery of fatty oils from Fructus Leonuri fruit . Among the five solvents tested, dichloromethane gave the highest recovery with Soxhlet extract ion (SE) , and ethanol gave the highest recovery with microwave assisted extraction (MAE) . In addition, the fatty oil content of the MAE extract was found to be only slightly lower than that of SE, but MAE was shown to permit comparable extract ion efficiency with 30 fold reduction in extraction time and 2 fold reduction in solvent consumption.