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The induction of tuberous roots of cassava in vitro is functional in MS medium containing 0.54 mM NAA, 0.44 mM BA and 3%-7% sucrose; meanwhile, the saccharide accumulation in the induced tuberous roots was increased with the sucrose content addition from 3%-7% in the inducible medium. Thus, the sucrose is an important factor for tuberous root induction in Cassava in vitro. The experimental results showed that the appropriate concentration of sucrose played a key role on the tuberous root induction in Cassava in vitro.

Contrary to high false positives rate of use White-box testing tools for Web application source code security and unable to locate vulnerabilities of use Black-box testing tools for Web application security, propose an effective method for combine White-box and Black-box testing tools of Web applications. This method will put the new technology of “Associated Files Matching Engine” into White-box testing tools, this test result and Black-box test result will be statistical analyzed and combined. Argumentation show, this method reduce the positives rate of White-box test result and be able to locate vulnerabilities where it is in file.

In this paper, the design and architecture of general digital image processing circuit (GFDIPC) based on a Xilinx Virtex-5 FPGA processor is presented. The GFDIPC applications on thermal imaging, image fusion, real-time video stabilization and time-delay test for image processing system are described. The design of FPGA in each application follows the principle of functional modularity, pipeline processing and parallel computing, which brings FPGA high efficiency and high real-time performance.

Chemical phosphorus removal is widely applied to enhance the biological phosphorus removal in order to meet the discharge requirement. Performance change caused by ferrous sulfate was investigated in this study. Compared to the control system which was not chemically dosed, pH and SVI slightly decreased while conductivity increased. The correlation between phosphorus and conductivity was weakened. The release and uptake of potassium declined, illustrating a negative impact of chemical precipitant on phosphorus accumulating organisms (PAO). The phosphorus uptake decreased while phosphorus release fluctuated. The phosphorus was not suitable for revealing the metabolic activity of PAO due to formation of ferric phosphate and ferric hydroxide.

This study investigates the influence of temperature and load on the dry sliding property of interface between brake friction material with low metallic formulation and gray cast iron disc. Full factorial design was employed to conduct pin-on-disc wear tests to attain wear and friction response under external heating temperature and applied load ranging from 25-175°C and 50-500N(0.35-3.5MPa), respectively. The analysis of experiment results shows the effect of load on wear rate is almost linear. Wear rate exhibits an increase followed by decrease trend with applied load. Friction coefficient is positively affected by external heating temperature but almost independent of applied load. Quadratic regression is conducted to fit the influence of temperature and load on wear rate and friction coefficient and the result shows sound fitting effect.

In 2009, the state offered relevant resolutions to build Shanghai into an international shipping center with global shipping resources allocation capacity, which gave fresh impetus to the development of Shanghai shipping center and have helped Shanghai rank the 2010 world 1st in container handling capacity. This paper will estimate the efficiency of Shanghai shipping industry from 2000 to 2010 using data envelopment analysis (DEA) and then evaluate Shanghai shipping center construction objectively and comprehensively through against cross-evaluation analysis and super-efficiency analysis. The results show that they are all technologically effective except the years of 2007 and 2008. Among technically effective years, the article concludes that the year 2009 was the optimal one through against cross-evaluation analysis whose experience is worth popularizing. The conclusion reveals that in future development of Shanghai shipping center, the government-led center development system should be transformed while paying more attention to promote the development of shipping information technology, high-end shipping services and shipping-related talent.

In order to prepare the keratin biological scaffold, keratin was firstly extracted from human hair by immersing in 200mL of aqueous solution containing 7mol/L urea, 2wt% Sodium dodecyl sulfate (SDS), and 5wt% sodium disulfite (Na2S2O6). The mixture was then heated to 95°C, shaking for 4h, and filtered through a stainless-steel mesh, dialyzed against 3L of distilled water, with cellulose tubing having a molecular weight cutoff of 10000~14000Da for 36h and filtered again. To examine the property of keratin scaffold, the vacuum freeze-drying process of pure keratin was investigated to find the optimum process. In order to further improve the property of keratin scaffold, different contents of Poly Ethylene Oxide (PEO) were added into the keratin solution. The result showed that the optimum freezing process was that Freezing at room temperature for 4h, and then put the sample into the refrigerator from ambient temperature to-20°C for 4h. Then the sample was put into the cold trap for 24h at-56°C. During the last 4 hours, the vacuum pump was opened and the frozen temperature was raised gradually. The keratin scaffold with good mechanical properties and uniform porosity was fabricated when the concentration of keratin solution was 10wt%. Additionally, PEO plays an important role in improving the flexibility of keratin/PEO scaffold.

Nanofiber nonwoven has been used in many fields due to the high surface area to volume ratio of the nanofibers and other extremely excellent properties. Nanofiber yarn, which is composed of long nanofiber with some twists for expanding nanofibers application, has been a challenging. A continuous nanofiber yarn was fabricated by a electrospinning technique with two oppositely charged spinnerets system in this work. The effect of process parameters such as applied voltage, the distance and the angle between the two spinnerets were examined in detail. The optimum parameters obtained included that the applied voltage was ±16kV, the distance and the angle between the two spinnerets were 8cm and 120o respectively. The nanofiber yarn has good potential applications in textile, medical, and biology.

The n-ZnO nanorods/p-Si nanowires heterojunction was fabricated by chemical method. The microstructure of the epitaxially grown ZnO nanorod was characterized by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The photoluminescence of the nanostructure showed a typical UV emission band and a defect-related emission band. Further, the electroluminescence of the nanostructure were measured, and the mechanism was discussed based on the band diagram of the n-ZnO nanorods/p-Si nanowires heterojunction.

Transparent indium gallium zinc oxide (IGZO) thin film was fabricated on SiO2/Si substrate by radio-frequency magnetron sputtering method. The IGZO thin film was characterized by X-ray diffraction, UV-VIS spectrometer, X-ray photoelectron energy spectrum to determine its optical, structural properties and binding energy information. The IGZO thin film was employed to construct metal-oxide-semiconductor field effect transistors (MOS-FET), which showed an on/off current of about 103. When the device was illuminated by UV light, the drain-to-source current was increased by 15 folders at -5 V gate voltages. The result indicates that the IGZO MOS-FET is sensitive to UV light.

For self-polishing coating with cuprous oxide serving as the main antifouling agent, the release rate of copper ions is one of the most important factors to evaluate its antifouling effect and validity period. In this work, experimental research was carried out involving the release rate as well as the panels in shallow submergence of antifouling paints with nanoadditives. The results indicated that the prepared coating with a slow and steady release rate in range of 20 to 25μg/(d·cm2) had a long-term and efficient antifouling performance. Synergistic effect of the photocatalysis activity of nanotitanium dioxide and the sterilization ability of cuprous oxide contributed to the antifouling effect in view of the evaluation of the antifouling panels in shallow submergence.

The effect of the nanoscale fractal tree-shaped network on the fluid permeation in wool fiber driven by capillary force was investigated in this paper. The fluid permeation obeys murrays law, and the permeation efficiency highly depends on the fractal dimension of the channel length. A better understanding of the mechanism of structural effect on the tree-shaped flow in the nanoscale fractal network of wool fiber could help the further design of bio-mimetic artificial fiber and functional fabric.

In order to predict the productivity of vertical well for shallow layer and low permeability reservoirs with horizontal fracture, based on the theory of horizontal fracture distribution and oil seepage in reservoir, establish the reservoir seepage physical model for shallow layer and low permeability reservoirs with horizontal fracture, and derive a novel deliverability equation, considering the effect of reservoir properties, fluid properties, horizontal fracture parameters and working systems. Furthermore, the equation was applied and performed sensitivity analysis to the productivity of a vertical well in Yanchang Chang 6 layer reservoir. Results show that vertical permeability, oil viscosity and the semiminor axis of horizontal fracture have more significant impact on well productivity. With real cases, it is demonstrated the established deliverability equation is simple and practical and meets the engineering accuracy requirements.

Braided composite tubular structures are of interest as viable energy absorbing components to improve vehicle passive safety. Unfortunately, there are many difficulties in predicting the crash response of braided composite tubes. In this study, a progressive failure model for braided composite materials, which had been implemented as a user material model in ABAQUS/Explicit, was used to simulate the axial crash response of braided composite tubes. It was shown that the model adequately captured the failure characteristics (such as matrix cracking, fiber fracturing and delamination) and energy absorption of braided composite tubes under axial compression. In addition, the simulation results show that braided composites have higher energy absorption performance compared to traditional metals.

In this paper, the high concentration polymer oil flooding experiments were first carried out on two artificial cores that with different Permeability (1000×10-3μm2 and 1700×10-3μm2) by using various concentrations of the polymer respectively(2000mg/L, 3000mg/L, 4000mg/L, 5000mg/L).The relationship between the polymer concentration and oil recovery was given, the upper limit of the polymer concentration was obtained according to the oil displacement efficiency, and the feasibility of the polymer concentration upper limit was investigated. Then it was found that higher produced water polymer concentrations were needed if the same the oil displacement efficiency was reached compared those fresh water polymer solutions by comparing the oil displacement efficiency that using produced water polymer solutions and fresh water polymer solutions.

The effects of RE metals on the inclusions and the impact property of 430 ferrite stainless steel were studied by metallographic examination, scanning electron microscope (SEM) and energy spectrum analysis. The results show that the morphologies and sizes of inclusions in 430 ferrite stainless steel are changed, and RE played a very good role of modifying inclusions. The fracture mode of 430 ferrite stainless steel is typical cleavage fracture, but quasi-cleavage and dimple fracture after adding RE into the steel. The transverse impact property of 430 ferrite stainless steel is improved obviously by RE. In comparison with 430 ferrite stainless steel without RE, the transverse impact property of 430 ferrite stainless steel with RE is increased 38.53% at -20°C, respectively.

Considering the efficiency and microscale requirement of melting polymer in micro-injection process, we present an experimental analysis of the CO2 laser irradiating Polyamide 12 (PA12) based on the photo-thermal effect of laser-materials interaction. The orthogonal experiments of laser plasticizing were designed by Taguchi method of Minitab software, the influence of process parameters on PA12 plasticization was investigated, and the effect sequence rule of the experiment parameters to melting depth was analyzed. Accordingly，the optimal process parameters combination on PA12 plasticization were obtained，i.e. laser power 3 W, beam diameter 2 mm, scanning velocity 200 mm/min, scanning distance 0.5 mm and environment temperature 20°C.

A good many ideas, strategies, cases and technologies of green building were brought forth in Expo 2010 Shanghai on the theme of “Better City, Better Life”. This papers deals with the analyze of these cases, and study how to put the application of green technologies and strategies into the urbanism of China base on the situation of the country, It could be significative and necessary for China when we want to create a resource-conserving and environment-friendly society and realize sustainable development.

Abrasion performance is an important performance parameter of polycrystalline diamond compact. This paper focuses on the research for test method of PDC abrasion performance. With the improvement method, the abrasion performance of PDC with five typical macroscopic interface structure such as planar structure, v-groove, u-groove, ring groove, ring claw-tooth are tested at normal temperature and after heating, With SEM, we study on its mechanism of abrasion performance due to different macroscopic interfaces structure, analyze the reason why PDC abrasion performance is different with the changing of PDC macroscopic interface structure. The research result shows that the temperature influenced the wear property and the anti-impact property of PDC obviously. In the same technological conditions, the interfacial structure of the PDC layer and WC-Co substrate has little influence on the abrasion performance, and the diamond and grains can sinter better, causing the excellent abrasion performance of PDC.

Chitosan/cellulose acetate multimicrospheres (CCAM) were prepared by the method of W/O/W emulsion with no toxic reagents and had the size interval of 200--280µm. It was investigated as an ideal alternative to enhancement the adsorption of water-soluble dyes from wastewater. The correlation coefficients of adsorption isotherm showed that the Freundlich model was comparable to the Langmuir model. The 1/n was lower than 1.0, indicating that malachite green was favorably adsorbed by CCAM. Furthermore, the amount of malachite green absorbed steeply increased with increasing time and reached plateau values within 2 h and increased with increasing of initial concentration of malachite green from 5 to 25 mg/g.

In this paper, the property of the ceramic corundum (SG) abrasives are studied with the way of roasting the ceramic corundum (SG) abrasives in the different roasting temperature, and using microscope, the change pattern of the ceramic corundum (SG) abrasives have been observed under different roasting temperature. The research results indicated that when the temperature achieves 900°C, the ceramic micrite abrasives start to have flaws, crack and hole. Therefore, the ceramic corundum (SG) abrasives with the roast, the manufacture and the application temperature to control in 900°C below, which guarantee the performance of the ceramic corundum (SG).

Wool fiber shows a natural crimp morphology, which endows textiles made of wool fiber with good elasticity and warmth-retaining performance. The natural crimp of wool fiber is due to the difference of the hierarchic structure of ortho-cortex and para-cortex of wool fiber. The present study investigated the fractal structure of ortho-cortex and para-cortex in detail to provide a new interpretation for the reason why the wool fiber has a natural crimp morphology and good performance in textiles.

This paper shows the effects of the XRD experiments on the different residual stresses of polycrystalline diamond compacts by XRD. Analyzing these effects in terms of the principle that field phase takes place coherent and incoherent diffraction reaction with X-ray, and applying to the Conpton- Youxun Wu’s theory that scattering intensity increases with the increase of sin/. This paper builds a mathematic model of semi-quantitative characterization of the residual stresses of PDC. For the XRD spectral line chart of PDC with known ranking residual stresses, diffraction reaction fails to happen in PDC when it is in low-angular domain, I   can be expressed as: I = K() / + I0, that means the XRD spectral line can be regarded as a beeline. Calculating all the K() values of PDC with the same specification but with the different surface of residual stresses according to the formula, this paper completes the semi-quantitative characterization of residual stresses of PDC with the same specification.

Micro-scale laser shock peening (μLSP) is a novel surface modification technique utilizing mechanical effect of shock wave induced by high intensity pulsed laser with micron spots. μLSP can introduce the beneficial residual compressive stress distribution in surface layers of metal with micron-level spatial resolution, and thus enhance wear resistance and fatigue performances of metallic micro-structures. The characteristics and influence factors of μLSP were briefly introduced, and progress in μLSP research fields was reviewed and presented, including laser induced shock pressure, material constitutive relation, changes of mechanical properties and microstructure evolution of materials. Finally, proposals on further investigations of μLSP were brought forward. The systematical characterization will lay the ground work for better understanding the effect of μLSP in microlength level and developing a more practical simulation method.

An allometrical scaling relationship between the solution concentration and the nanofiber diameter in bubble electrospinning was established. The scaling law was validated with experimental results using bubble-electrospun Polyvinylpyrrolidone (PVP) nanofibers at different concentration PVP solutions. The results showed that the average diameter of PVP nanofibers increased approximately exponentially with solution concentration in bubble electrospinning process. The experimental data agreed well with the theoretical predictions, and showed that the present model had high prediction accuracy.

Satellite calibration antenna suffered rigorous vibration environment in the course of lunching. Random vibration is being specified for acceptance tests by spacecraft structure. The waveguide tube of antenna was cracked in the random vibration test. Fracture analysis using scanning electron microscopic showed that failure were induced by fatigue damage. Finite element model of antenna was built and root mean square (rms) stress of waveguide tube was obtained in random vibration analysis. The maximum rms stress was 35.6MPa and located at the flange base. Then fatigue life of waveguide tube was estimated, using the Palgren-Miner rule and the three-band method. The estimated fatigue life of 109 seconds showed the waveguide tube couldn’t ensure safety during 120 seconds of the random vibration. Finally two ribs were added at each flange base for decreasing the stress concentration. The fatigue life of improved waveguide tube was 811 seconds. Then it passed the random vibration test.

ZrB2-SiC and ZrB2-SiC-C ultra-high temperature ceramics (UHTCs) were fabricated by pressureless sintering under an argon atmosphere. The mass and linear ablation rates were tested in an oxyacetylene flame with high velocity. The microstructure and phase transformation of the ZrB2-based UHTCs were characterized by scanning electron microscopy along with energy dispersive spectrometry. Results show that the UHTCs have excellent properties of ablation resistance at ultra-high temperature. The values of mass and linear ablation rates were lower in the ZrB2-SiC UHTCs than those measured for ZrB2-SiC-C. The effect of C addition on the ablation resistant was not obvious but it influenced the microstructure of the ZrB2-SiC UHTCs. And the ablation resistant mechanisms of ZrB2-based UHTCs were discussed according to microstructure analysis.

With AlN, Al2O3 and Al powders as starting materials, ALON powders were prepared by high temperature solid state reaction at 1650°C, 1750°C and 1850°C respectively. Nitrogen gas at 1atm was selected as reaction atmosphere. X-ray diffraction analysis and scanning electron microscope analysis were carried out for the as-prepared ALON powders. In this paper, single-component γ-ALON porous materials were obtained at temperatures below 1800 degree with void ratio more than 75%, which is prone to be grinded to powders less than 1μm and applicable for the preparation of transparent ceramics. Aluminum oxynitride spinel γ-ALON transparent ceramics were successfully obtained with the as-prepared ALON powders. The volume density of the transparent ceramics was 3.67g/cm2, which is 99.3 percent of the theoretical density of γ-ALON materials. The bending strength of the transparent ceramics was 296MPa and the transmittance was about 75% in the wavelength range of 1.2 to 5.3μm.