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In recent years, due to the unique advantages of nanomaterials, they are widely used in many fields (including the field of tissue engineering, protective clothing, filters, sensors, etc.). How to prepare nanofibers has become a hot research topic. This paper outlines status quo of a class of preparing nonafibres. And this preparation is the centrifugal spinning including melt centrifugal spinning, centrifugal electrospinning and solution centrifugal spinning, which have broad prospects for development. And this paper also briefly describes theirs advantages and disadvantages. Finally, the development trend of centrifugal spinning is summarized.

Horizontal oil and gas drilling has become one of the most valuable technologies ever introduced in the unconventional drilling especially. Nevertheless, it is complex to calculate the horizontal wells’ true formation thicknesses in the dipping strata. Combined with the actual geological conditions and mathematical methods, a complete set of new formula was derived from the basic data of the strata dips, dip directions and individual layer data to calculate the true formation thicknesses, which could obtain the horizontal wells’ true thicknesses of Penglaiba Formation of Lower Ordovician in the northern Tarim Basin. And the calculation results were accurate. Calculated with this formula, the Penglaiba Formation’s true thickness was given, wells’ relative distributions were located, and the columnar section of Penglaiba Formation was spliced to discover the geological situation subsurface accurately. The columnar section of Penglaiba Formation in the northern Tarim Basin could provide a theoretical basis for reservoir prediction and the distributions in the low permeable beds. This is the key technical method to descript the palaeogeologic map.

The polypropylene/sisal fiber composites were prepared by twin screw extruder and vane extruder, respectively. The tensile test specimens perpendicular to the extrusion direction and parallel to the extrusion direction were prepared from the extruded composites, respectively. SEM observation showed that fiber orientation of sisal fiber in the composites was not obvious when the content of sisal fiber not more than 15wt%. When the content of sisal fiber was 15wt%, the ability to orientate of sisal fiber in the composite prepared by vane extruder was better than that of in the composite prepared by twin screw extruder, which the fiber orientation of sisal fiber was obvious along the extrusion direction in the composite. Tensile tests showed that the tensile properties of the composite parallel to the extrusion direction with 15wt% sisal fiber prepared by vane extruder were the best compared with other composites in this work. The results illustrated that the orientation of sisal fiber in the composites was beneficial to the improvement of the tensile properties of the composites.

The correlation between Normalized Difference Vegetation Index (NDVI) and environmental factors is examined at different scales and locations in world heritage of Wuyi Mountain by wavelet coherency. These factors are elevation, slope, aspect, distance to nearest resident, distance to nearest road , and distance to nearest river along two transects based on data of DEM, residents, roads, rivers and ALOS remote sensing image in 2009.The results show that:(1) The relationships between NDVI and environmental factors change along with scale. The relationships between NDVI and environmental factors in the first transect are all weak at small scale (<480m). At medium scale (480-7680m), NDVI is significantly correlated with elevation, slope, resident , and road. At large scale (>7680m), NDVI is significantly correlated with elevation, resident and river. For the second transect, NDVI is significantly correlated with aspect at small scale; and significantly correlated with elevation, aspect, slope and river at medium scale; and significantly correlated with elevation, aspect, and slope at large scale. Thus elevation is the dominant controlling factors on the vegetation cover.(2)The relationships between NDVI and environmental factors also change when location changes. There is positive correlation between NDVI and elevation below the altitude of 600 m and the windward side of the southeast monsoon above 600m, while it is negative in the leeward side above 600m. Besides, NDVI is directly related with road, resident, slope, and river in the areas where the elevation is below 1200m, but inversely above 1200m.

Diamond-Like Carbon (DLC) films were deposited on quartz substrates by using a gas mixture of hydrogen-methane-oxygen in the Star-Shape Microwave Plasma enhanced Chemical Vapor Deposition (MPCVD) reactor. The pretreatment parameters include the pretreatment methods and the pretreatment time was optimized. Results showed that ultrasonically abrasive in the acetone solution with nanocrystalline diamond powder in it was an efficient pretreatment method to advance the deposition of DLC films, and 10 minute turned to be the most appropriate time for this pretreatment. The Fourier Transform Infrared spectrometer (FTIR) showed that the DLC films synthesized by the optimized technics have high transparence fit for optical applications. These indicated that the Star-Shape MPCVD reactor was the perfect equipment for the volume-produce of DLC films for its unique big reactive cavity.

The Dissolution of Synthetic Pyromorphite was Studied at 25°C in a Series of Batch Experiments. in Addition, the Aqueous Concentrations from the Batch Dissolution were Used to Calculate the Solubility Product and Free Energy of Formation of Pyromorphite. the Results of the Fourier Transform Infrared Spectroscopy Analyses Indicated that the Synthetic, Microcrystalline Pyromorphite with Apatite Structure Used in the Experiments has Not Changed after Dissolution. the Mean Ksp Value was Calculated for Pb5(PO4)3Cl of 10-78.31 at 25°C; the Free Energy of Formation ΔGf0[Pb5(PO4)3Cl] was-3756.82kJ/mol.

a novel configuration for a novel ultra wideband switch is presented in this paper. This switch using 0.5um GaAs process in ADS2008 simulator. Switch should be designed to trade-off insertion loss, isolation, bandwidth, and return loss. The aims of design are to provide low insertion loss along with high isolation. The design using integration inductor and resistor in parallel, and this switch exhibits high performance: over DC-10.6GHz, insertion loss is lower than-1.624dB; the ripple variation of insertion loss is less than ±0.25dB; The isolation is lower than-51.336dB; input return loss is lower than-16.402dB; on state, output return loss is lower than-15.919dB; off state, output return loss is lower than-18.294dB; on and off time are less than 4ns.

The nanocrystalline FeCoNbB films are made by magnetron sputtering. The magnetization saturation of the filmes increase with the film thickness. The complex permeability spectra of the samples vary with the thickness of the film as well. The relaxation frequency is much higher than that of FeCoNbB ribbons because of magnetocrystalline anisotropy. The amplitude of the real part of the permeability decreases with the rising thickness of the film. This phenomenon suggest that the random anisotropy theory is to somewhat applicable for thin films. The X-ray diffraction pattern and the shape of the hysteresis loop show the crystal grains grow with the increase of the film thickness and also result a deterioration in magnetic softness.

There is a huge amount of coal mine ventilation air methane emitted into the atmosphere directly each year in china, not only causes a lot of energy was wasted, but also do severe harm to the protection of the environment. The Utilization Technologies of coal mine ventilation air methane (VAM) are receiving more and more attention from people, Aiming at the domestic and international development status of VAM utilization, Thermal flow reversal reactor (TFRR) and catalytic flow reversal reactor (CFRR) are introduced, as two kind of flow-reversal oxidation technology which are the most popular and used widely. The economic and applicability about service life, total cost, space and performance of device are comparative analyzed, and illustrate the trends about the technology of flow-reversal oxidation of VAM from two aspects: to solve the problem of running stability well and improve its work efficiency reasonably. Finally, this paper outlines the future prospect for the development of this technology.

On the basis of the working principle of the large gap magnetic drives system, the distribution principle of system’s spatial magnetic field under the 4 pole states of T78 electromagnet along the direction and the direction was measured. The experiment results were analyzed. The study results show that the permanent magnet can be placed in a more powerful magnetic field in its rotating period and could get large magnetic field’s coupling force by increasing the current properly, decreasing the coupling distance of magnetic pole between electromagnet and permanent magnet, and putting the permanent magnet into the ±5-10mm range of electromagnet.

The effect of fly ash (FA) and slag (SG) on the anti-cracking performance of recycled aggregate concrete (RAC) is discussed, taking the toughness index as the concrete anti-cracking performance evaluation index, and the mechanism of action is researched at the meantime. The experimental results show that the strength of RAC is reduced when containing fly ash only or slag only, but the crack-resistance of RAC is improved significantly at 3 days and 28 days of hydration process of RAC. Furthermore, the 28 days anti-cracking performance of RCA improved significantly with 30% FA single-doped or 20% SG single-doped .It can improve the 28 days anti-cracking performance of RAC, by using double-mixture of fly ash and slag, there is an optimal FA/SG ratio and a best total content, the FA/SG ratio is 3:1 and the total content is 30%.

An orthogonal experimental design method was adopted for the mix design of high early strength recycled aggregate concrete (HSRAC), and the influence of water-binder ratio, percentage of recycled aggregate(RA）and highly active compound mineral admixture (HACMA) content on the strength of the concrete was discussed. The test results indicated that water-binder ratio was the most principal and significant influencing factor on the strength of HSRAC, regardless of age. An empirical relationship among the strength of HSRAC, the water-binder ratio, the percentage of recycled aggregate and HACMA content was proposed by using multivariate regression analysis. The demand of opening heavy or heavier traffics and rapid repair concrete on strength to HSRAC could be all met.

The terpolymer was synthesized by maleic anhydride (MA), acrylic acid (AA) and methyl acrylate (MAC) and the structure was also conformed. Its scale inhibition effect was also studied in high barium and strontium ion concentration aqueous medium and simulated formation water (Ca2+, Mg2+, Ba2+, Si2+) condition. The results indicate that when additive amount of AA/MAC/MA is 60 mg/L, the inhibition rate is up to 100% and 80% for BaSO4 scale and SrSO4 scale respectively, but only 50% for calcium scale. And the scale inhibition rate moderately increases with the dosage increasing. The scale inhibition effect of AA/MAC/MA is also very obvious in simulated formation water containing low calcium ions (400 mg/L) and high barium ions (500 mg/L) as well as strontium ions (500 mg/L). It can satisfy the need of restraining composite scale (BaSO4 scale and SrSO4 scale as well as CaSO4 scale) in high calcium and barium strontium ion aqueous medium when compounded with calcium scale inhibitors CY and CX respectively.

The incidence of algae blooms is increasing in China and worldwide, causing serious environmental problem. A protozoan P1 was isolated from the water samples of Lake Dianchi, which had potent grazing effect on some kind of cyanobacteria. It should be belonged to Ciliophore, Oligohymenophorea, Philasterida based on morphological characters observed by the optical microscope. The main influencing factors of the protozoan grazing properties including: algae species, protozoan density, culture temperature, time and pH value were investigated in batch experiments. The results showed that the protozoan P1 had strong ability to graze the cells of Microcystis wesenbergii. The greater the initial protozoan density, the faster the degradation of chlorophyll-a. The removal rate of chlorophyll-a after 4 days was 78% at the optimum temperature 25℃, pH 7 when using a lower inoculation quantity of 2%. The protozoan P1 was easy to cultivate and reproduce rapidly. It could be applied in the ecological environment to control the Microcystis water bloom.

Traditional decoupling control strategy of doubly-fed induction generator (DFIG) wind turbine makes little contribution to system inertia and do not participate in the system frequency control, the synchronization of large-scale wind power requires wind turbine have the ability to participate in the regulation of power system frequency. This paper adds a frequency control segment to traditional DFIG wind turbine and considers the doubly-fed wind turbine operating on the state of the super-synchronous speed, by analysis the effect of inertia and proportional control strategies, a fuzzy control strategy which combines the advantages of the former two control strategies is proposed, simulation results show that this control strategy can more effectively improve the system frequency response.

In this paper, the conventional method to acquire Thevenin equivalent parameters is described. The method is based on features of power systems and utilizes the base-case system information. Considering the impact of loads on Thevenin equivalent potential and impedance, this paper makes improvements and brings it closer to the actual situation. The necessary condition about limit power transmission is derived, and the impedance modulus margin can be used to determine voltage stability of power system. Finally, the results of IEEE-14 bus system calculations show effectiveness of the method.

Integrated progress of S&T is the important factor in the Economic and Social System. Based on the analysis of the economic and social growth and integrated progress of S&T in Hubei Province during Eleventh Five-Year, with the concept of the system and in the perspective of input and output, this paper used the national statistics and the regional scientific and technological progress monitoring indicators, put forward to the deep comparative analysis among Hubei and Guangdong, Jiangsu, Shandong, Zhejiang and Fujian provinces in the eastern on socio-economic growth, integrated progress of S&T and promotion of S&T to economic and social development, then some countermeasures how Hubei to enhance the role of S&T were put forword.

GM (1, 1) model is a widely used model for forecasting. The characteristics of the model have been analyzed. The fact that the model is a biased exponential model has been testified. Based on the results, UGM (1, 1) model is presented in this paper. The proposed model has more extensive application scope than GM (1, 1) model for the reason that the model can limit the inherent deviation of GM (1,1) model. The proposed model is applied to the field of electric load forecasting, the actual results also show that the model is better than GM (1, 1) model.

Compared with the method of common design, the generative design that considering more application of semantics is more suitable for the design of new Chinese furniture. Make a comprehensive survey upon the design example in new Chinese furniture, its generative design develops mainly towards two directions: One is towards the design about the characteristics of DNA, the design compromising the classic elements in Chinese furniture and modern life style, cultural consciousness, social perception; while the other is about the arrangement pattern of DNA, the design harmonizing the classical form in Chinese furniture and modern interior circumstance, living articles, delight of life.

This paper studies the chemical mechanical polishing (CMP) of the wafer's material such as stainless steel, monocrystalline silicon etc, and analyzes how the technological parameters’ impact on the final wafer’s surface material removal rate, surface quality and surface damage like the polishing pad’s speed and the wafer speed, polishing pressure and polishing time.The results show that: when the difference between the polishing pad's rotation speed and the wafer's rotation speed is small and their directions are the same , then the material removal rate of the wafer is larger.when the polishing pressure is selected between 5 to 6.5 kPa, the wafer surface's damage is smaller.The polishing time also play a very important role and affect the surface quality and surface damage of the wafer after polishing.

In order to improve the mathematical description quantitatively, and support decision in tobacco crop knowledge. A Good quality flue-cured tobacco production and management decision support system (GQFKMTDSS) has been designed and developed applying JSP under the Windows Server environment, based on good quality flue-cured tobacco knowledge model with system analysis methods and mathematical modeling techniques. The system helps for forecasting function and guiding decision-making to good quality flue-cured tobacco.

An electrochemical sensor modified with tetra-(N-phenylpyrazole)-porphyrin/b- cyclodextrin/carbon nanotube (TPPyPh/b-CD/CNT) film was fabricated for determination of hemoglobin (Hb) in this paper. The electrochemical behavior of the proposed sensor was investigated by cyclic voltammetry (CV). TPPyPh has been shown preferably for the fabrication of electrochemical sensor. The peak currents decreased significantly with the increase of the Hb concentration in solution. The response mechanism of TPPyPh/b-CD/CNT film for Hb was suggested to be based on the coordinated interaction between Hb and TPPyPh. It showed excellent selectivity for the determination of Hb in PBS.

Hyperspectral imaging (400-1000nm) and artificial neural network (ANN) techniques were investigated for the detection of nitrogen content changes of rape leaf. Measuring SPAD value of rape leaf by using SPAD (Soil and Plant Analyzer Development).A hyperspectral imaging system was established to acquire hyperspectral data. Principal component analysis(PCA) was used to obtain principal component images, as well as to select the optimal wavelength(s). ANN was applied to establish the model between the spectral reflection values and SPAD values. The prediction results were obtained for the nitrogen content of rape leaf with the correlation of prediction of R=0.9237. The results show that the hyperspectral imaging has good classification on different nitrogen content of rape leaf.