2014 Vol. 29, No. 4
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The MnO2/graphene/polythiophene composites were synthesized by in-situ hydrothermal oxidation-reduction method.The morphology and crystallinity of the composites were characterized with scanning electron microscope (SEM) and X-ray diffraction spectroscopy (XRD).The electrochemical charge-discharge performance of the nanocomposites was tested by the battery test system.The results showed that globulg MnO2 was grown both on the surface of graphene and the gap of large particles of polythiophene in the nanocomposites. The specific capacity of synthesized MnO2/G/PTh composites was 300 mAh/g after the cycle of 20 times,the first charge and discharge efficiency of the nanocomposites with the ratio of 20:1:0.67 was 46.5%,the discharge capacity was the highest. The charge-discharge stability and coulombic efficiency of the MnO2/graphene/polythiophene nanocomposites were better than that of pristine MnO2.
Graphene/gold nanoparticles/polypyrrole (G/AuNPs/PPy) nanocomposite was prepared by in-situ chemical oxidation method,then DNA was immobilized and hybridized on the surface of the composite.The chemical structure,element composition and surface morphology of the nanocomposite were characterized by Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,field emission scanning electron microscope and transmission electron microscopy,respectively.Afterwards,electrochemical cyclic voltammetry,impedance spectroscopy and electrochemical quartz crystal microbalance were used to determine the variation of electrochemical properties and weight of the nanocomposite before and after DNA immobilization/hybridization.It demonstrated that the electrochemical activities of G/AuNPs/PPy were better than that of G/AuNPs nanocomposite.The immobilization amount of DNA on the G/AuNPs/PPy nanocomposite was 307 ng,and aslo 357 ng of perfectly matched target DNA was detected on the surface.
The nanopowders of La1-xKxFeO3(x=0,0.1,0.2,0.3,0.5) were prepared by a citric acid sol-gel method.Their microstructure and ethanol-sensing properties were investigated.The results showed that with the doping of K+ the obtained powders were an orthorhombic perovskite structure,and the doping of K+ could restrained the growth of the grain size.The K+ doping enormously enhanced the conductivity of the samples.The gas sensors based on the La0.7K0.3FeO3 showed higher sensitivity to 3×10-4 g/cm3 ethanol gas,and had better selectivity and response-recovery.
ZnWO4/bamboo charcoal (ZW/BC) photocatalysts were synthesized by the microwave assisted sol-gel method with 5(NH4)2·12WO3·5H2O as the W source,and bamboo charcoal as the support.The structured features of these materials were analyzed by TG,while their morphologies were characterized by SEM and BET.High efficiency for the degradation of Rhodamine B (RhB) under both UV light was obtained for the ZW/BC photocatalysts.The results indicated that the composites with 20%(wt) bamboo charcoal sintered in air at 400℃ for 10 min in microwave power 640 W charactered had the better photocatalytic ability in the UV light.
In order to investigate the antioxidant activity of Maillard reaction products (MRPs) in the methanol solvent,the glycine-glucose simulation system was adopted,with DPPH free radical scavenging as antioxidant activity index of MRPs and pure water system of MRPs antioxidant activity as the contrast.The optimum concentration of methanol was investigated.Under this methanol concentration,the effect of reaction temperature,reaction time,pH and concentration of reactants on MRPs oxidation activity were studied,and optimum technological conditions were obtained by uniform test.The results showed that under the 40% methanol concentration as the solvent of glycine-glucose simulation system,the DPPH free radical scavenging rate of MRPs was the highest,the antioxidant activity was the optimal.The optimum technological conditions were as follows:temperature 127℃,60 min reaction time,initial pH=8.0,the ratio of glycine and glucose 2.5:1.
In order to acquire rabies virus G gene and express it in E.coli and establish the evaluation method for rabies virus immune, according to Rabies virus ERA G gene sequence to design primer sequences,RNA was extracted from rabies virus,the first strand cDNA was synthesized by reverse transcription.G gene fragments were amplified by PCR.Then the gene fragment was cloned to the prokaryotic expression vector pET28a (+) to construct PET-RVG.The positive recombinant plasmids were transfected into E.coli BL21(DE3)gold,with IPTG induced expression and determined the best expression condition.Using Niaffinity chromatography purification with G protein,and the indirect ELISA assay for the detection of rabies virus antibodies in serum was established based on the G protein.The results showed that the purity degree was 96%.
Using colloidal gold-labeled mouse anti-human IgM μ chain antibody,Mycoplasma pneumoniae P1 protein antigen for coating,immuno-gold preparation conditions were optimized to prepare colloidal gold immunochromatographic test strip.The test strip kit was contrasted with that in market,total coincidence rate was 99.17%.The results showed that the test strip had high sensitivity,specificity,low price.It was more suitable for MP infection in early clinical screening,and was easy and quick to operate.
With the effects of different filter ventilation on the total particulate matter in mainstream smoke the transfer law of volatile alkaline,acidic and neutral,ingredients and plused aroma were reviewed.At the same time,it pointed out that the main research direction was to improve the quality of cigarette by changing the filter ventilation,reducing cigarette tar and adding extra aroma.
A method for the detection of 3,4,5-trihydroxy benzoic acid in tobacco essence and flavor was developed by using high performance liquid chromatography.After oscillate-extraction by ethanol,the samples were separated by a C18 column (100 mm×3.9 mm,5 μm),using methanol and 0.05% phosphoric acid (6:94) as mobile phases by isocratic elution,and detected by diode array detector with the wavelength of 272 nm.The experimental results showed that:within the range of 0.1~10.0 mg/L,the linear correlation coefficient for 3,4,5-trihydroxy benzoic acid was 0.999 4,the low detection limit was 1.01 μg/g,the recovery was 93.1%~103.2%,the RSD < 5% (n=5).The method was sensitive,accurate and easy-controlled,and it was suitable for quantitive determination of 3,4,5-trihydroxy benzoic acid in different types of tobacco essence and flavor.
To reduce the number of defective products and the downtime caused by the blockage of cigarette conveying line,the alarm control unit was designed to solve blockage of cigarette conveying line.The jam detection device in power head area was installed.By PLC and inverter switch interface, and installation of LED large screen,rapid locating alarm position was achieved. It would alarm timely and indicate jam accurately when congestion occured.The quantity of defective tobacco products could be controlled under ten compared to the previous situation when each congestion occured and the average time of troubleshooting was shortened from thirty minutes to less than five minutes after the device was adopted.The device could improve work efficiency and reduce the rate of defective products.
Aiming at the probelm in the permanent magnet synchronous motor (PMSM) vector control with high demand of hardware,bad effect of low speed and no regard for changes of resistance,on the basis of model reference adaptation system (MRAS) model,a new adaptive law was designed to implement real-time identification of rotational speed of motor and stator resistance.A Matlab simulation platform was established by the application of this algorithm.The simulation results indicated that the improved MRAS model could operate when stator resistance had changed.Compared with the simulation result of the traditional MRAS model,the effectiveness and superiority of the algorithm were proved.
Aiming at the problem of the modelling of stochastic time delay in network control system (NCS),a time delay dynamic model was put forward based on the experimental data by analyzing the cause and construction of the time delay in NCS and constructing an experimental platform to acquire the real time stochastic delay data.The proposed model could describe the characteristics of the network time delay more accurately and be used in time delay prediction and high performance time-delay compensation controller design of NCS.
Using an asynchronous motor as controlled object,the new ADRPI soft-switch three-phase inverter circuit and the actuation control circuit diagram of inverter electric circuit were designed,and based on many experiments for inverter circuit design and driving control circuit the concrete improvement measures were proposed,using the new type of soft switch inverter circuit and the selection and design of the drive control circuit component parameters.The experimental results showed that pinnacle impulse from the inverter circuit output signals of ADRPI soft-switch invertor circuit was restrained and the inverter circuits output characteristic was improved,so the quality of output current of inverter has been obviously improved.
Aiming at the common problems that automatic dosing device for circulating cooling water in the field of heat-engine plant in China had a single parameter and was unable to real-time monitoring,a new intelligent dosing system for circulating cooling water basis on multi-parameters was designed.A group of new core parameters were proposed by the dynamic simulation experiments on the basis of traditional detection parameters,such as pH,electrical conductivity,and ORP,and at the same time,the mathematical model was established.The simulated-heat-exchanger was designed which could optimize the self-adapted fuzzy control algorithm and establish the expert diagnosis system.The result of running this system showed that it had high efficiency and intelligence,and could give the optical dosing scheme according to water quality and operation status compared with traditional dosing system,it could reduce the drug cost 25%,save water 31%,and reduce the energy consumption 20%,which improved the economic benefit greatly.
Aiming at the problems that the existing water quality monitoring instrument measurement parameters are relatively single,poor real-time,low accuracy of measurement degree,a multi-parameter water quality real-time monitor instrument was designed based on ARM+FPGA.Adopting the method of multiplexed signal acquisition and storage on water quality.This instrument used the parallel working mode of FPGA to conduct,and processed by the ARM processor.The experimental results showed that:the water quality monitor parameters had high measurement accuracy,good real-time,stable and reliable performance,the measurement indexes could meet the design requirements.
Aiming at the problem that the traditional stereoscopic video coding technology had lower compression rate,poor stability,higher color distortion,a new three-division video encoding technical method was proposed based on QNX.The scalable video encoding algorithm was used,field frequency division complementary color encoding prototype was designed.Video signal which was processed by the vertical frequency of the octave field was transmitted by sharing complementary color field.The experiments showed that this method could not only render picture frames smoothly to the left-right viewpoint,but also enhance the sense of immersion of stereoscopic television effectively.
When collecting the QR code image,the inclined or geometric distortion often occured.To solve this problem,a correction method combined the QR code feature,image rotation and image maps was proposed.This method,firstly,used the position detection patterns to detect tilt aberration after conventional image pre-processing and run length encoding;Secondly,selected the appropriate method by tilt aberration to correct the image;Thirdly,used grid and statistical methods to extract information and complete the decoding.The results showed that the method was simple and had a high rate of recognition.The computation of floating-point was small,so it could be used in embedded system.
Aiming at the problem that traditional saliency detection only consider regional precise positioning and extraction,while ignoring semantic background among the image,a significant detection method based on situational awareness was presented.This method used the local-global single-scale to extract the saliency and then multi-scale to enhance saliency.In view of the method which could extract the contents more conforming the characteristic of human vision,it could express the meaning of the image better.But the computing complexity was higher.
Aiming at the problem that IEEE 802.15.4 MAC protocols in wireless sensor networks had high delivery latency,an improved low-delay MAC mechanism LD-MAC based on the existing LE-MAC protocol was proposed.The protocol reduced the delivery latency by improving the number of CCA.When the backoff counter reached zero,the node performed carrier sensing that consisted of clear channel assessment (CCA) for the next CW consecutive backoff slots.If the channel was sensed idle during the first CCA,the node tansmitd the data directly. The properties of the improved mechanism were analyzed theoretically by using two-dimensional Markov chain model. The simulation results showed that LD-MAC not only reduced the delivery latency but also improved the throughput significantly by only increasing energy consumption slightly.
Aiming at the problems of the most of the emergency resource scheduling management system at the present such as response slow,low efficiency,step overstaff and so on,a GIS-based emergency resource scheduling management system was designed.The system used B/S three-tier architecture, WebGIS development techniques,SuperMap SDX+ spatial database technology and the shortest path algorithm Dijkstra to design.The system abstracted resource reserves points, intermediate distribution points and the distribution of the affected land for each point, and the entire route was seen as a resource scheduling network diagram sections, basing it to organize them into a space network traffic map, making scheduling charts and tables in the GIS for expression through space network diagram.The test results showed that the system was versatile, stable in performance,which improved the visualization and intuition of material scheduling decisions to achieve the desired goal.
Aiming at the problems of traditional software defect tracking and management system such us poor user experience and low business efficiency etc.,a software defect tracking management system based on DSH architecture was designed and realized.The system was constructed by B/S mode, using Dorado presentation middleware and mainstream Java Web technology such as Spring, Hibernate, etc.The system realized the functions of project management, user management, defect tracking management, defect data statistical analysis, report output and so on.The application practice has indicated that it improved the page graphics display and user experience, had good scalability and maintainability, and was suitable for defect tracking of small and medium scale software development.
Aiming at the application limitation of present E-learning platform,learning space based on cloud Web was designed and realized.The learning space was developed on the basis of MOOC and data management functions,by using open source Saki platform,Java EE enterprise-level development platform and Oracle database.The learning space realized a tri-layer function featuring unified certification,platform application & service and data storage.The trial finding showed that the could Web learning space had stable performance and promoted interaction between teaching and learning,enhanced collaborative learning and shared of data source so as to implement the traditional learning platform.
Considering the Cramer-Lundberg model with dividend payments and capital injections in the presence of both transaction and administration costs,in order to maximize the discounted dividend payments minus the penalized discounted capital injections and the costs,by stochastic control theory and the corresponding Hamilton-Jacobi-Bellman equation,a method to determine numerically the solution to the integro-differential equation was derived and showed that the optimal strategy was band type.This conclusion which put forwords the theory of former researchers was widely used,and made the risk model more realistic.
By analyzing the mechanism the relevant physical and mechanical formula that Manning's relationship with the first draw frame size were derived,and then permeable frame length was positively correlated with the rate of deceleration was gotten by the transitive,and their relationship expression was η=Aa2+Ba+C(A,B,C coefficients are constants) was finally gotten.Through the relevant tank test, the experimental data could be measured,which was obtained for the experimental data fitting,and the same results and conclusions of the analysis mechanism were found.Advantage of this model was a mathematical method of analysis and data fitting mechanism,which improved the accuracy of the original analysis of the results of the experiment,and therefore could be used in practice.
Founded in 1986, bimonthly
Administered by:The Education Department Henan Province
Sponsored by:Zhengzhou University of Light Industry
Editor-in-chief:Wei Shizhong
Executive Editor-in-Chief:Zou Lin
Deputy Editor-in-Chief:Qu Shuanghong
Edited & published by:Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address:136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code:450001
Tel:(086)0371-86608635
(086)0371-86608633