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Development of tight oil reservoirs mainly relies on massive hydraulic fracturing, which can generate complex fracture networks in the reservoirs. These highly discrete fracture networks bring great challenges for reservoir simulation. An efficient model applying an unstructured discretization method and automatic differentiation is proposed. The flexibility in unstructured control volume shapes enables the gridding of complex fracture systems. By introducing the concept of half-transmissibility for each grid, transmissibility list including connections of matrix-matrix, matrix-fracture, fracture-fracture is established. Nonlinear flow and transport equation system is solved by a modified Newton’s method, in which the Jacobian matrix is computed by automatic differentiation (AD). Accuracy of the model was validated by performing simulations using a commercial simulator. We implemented our model in several cases with a uniform physical domain (radial model with diameter=1 km) but different fracture properties. Results show that fracture configuration and property have significant impacts on the production. Moreover, our model shows a high efficiency in the densely fractured system with fracture density up to 1018/km2. The novelty of the model is in the ability to represent complex fracture systems individually and explicitly, and in the application of automatic differentiation, which greatly facilitates the model establishment and improves computational efficiency.

Due to the excellent oxidation and hot corrosion resistance and matched thermal expansion coefficient to normal alloys, Cr2AlC has potential applications as high-temperature protective coating. In the present work, the preparation of Cr2AlC coating has been achieved through cathodic arc deposition method combined with heat post-treatment. It was found that the coating, deposited from Cr2AlC compound target in the unintentional heating condition, was amorphous. After annealing at 620 degrees C in Ar for 20 h, the amorphous Cr-Al-C coating happened to crystallize and transformed to crystalline Cr2AlC as the major phase. It is obvious that the formation temperature of Cr2AlC was decreased from about 1050 degrees C for sintered bulk to around 620 degrees C for the as-deposited coating, resulting from the homogeneous mixture of the Cr, Al and C at atomic level in the Cr-Al-C coating. Apart from crystalline Cr2AlC, the annealed coating also contained AlCr2 and little Cr7C3. AlCr2 formed due to the loss of C during deposition, and little Cr7C3 always existed in the sintered Cr2AlC compound target as impurity phase. (C) 2012 Elsevier B. V. All rights reserved.

The failure components made of silicon is an important issue in the electronic and nano-technological developments. A study on the near-crack-tip deformation of single-crystal silicon wafer under tensile load was presented. The strain formulas around the crack tip of mode I crack were deduced from linear elastic fracture mechanics. The strain fields around the crack tip were simulated and analyzed in detail.

Microcrystalline boron-doped diamond (BDD) films were prepared on silicon substrates by hot-filament chemical vapor deposition method. Different grain sizes of the boron-doped diamond films with nearly the same boron concentration were obtained by changing the nuclei concentration on the silicon substrates. The electrical transport behaviors of as-prepared boron-doped diamond films were measured, and the results revealed that with the increase of the grain sizes on the BDD films, the superconducting transition temperature was evidently increased. This phenomenon indicates that the superconducting transition of microcrystalline BDD films is influenced by the inhomogeneity aroused by the grain boundary effect. Our results could expand our understanding of the superconducting mechanism of microcrystalline BDD films, and are also significant to conventional applications of BDD materials.

Guo's et al. comments on our paper (Z.T. Guo, J.Y, Ge, G.Q. Xiao, Q.Z. Hao, H.B. Wu, T. Zhan, L. Liu, L. Qin, F.M. Zeng, B.Y. Yuan, Comment on “Mudflat/distal fan and shallow lake sedimentation (upper Vallesian–Turolian) in the Tianshui Basin, Central China: Evidence against the late Miocene eolian loess” by A.M. Alonso-Zarza, Z. Zhao, C.H. Song, J.J. Li, J. Zhang, A. Martín-Pérez, R. Martín-García, X.X. Wang, Y. Zhang and M.H. Zhang [Sedimentary Geology 222 (2009) 42–51], Sedimentary Geology, 2010-this issue) mostly stress their previous data and their model of configuration and evolution of the study area; it is not a real discussion of the sedimentological features we describe. In this reply we will discuss some of the key features of the basin configuration, correlations and sedimentology of the Tinshui basin. Our work has followed the common procedures used in stratigraphy and sedimentology and so we can confirm our interpretation on basin configuration and correlations. In all cases we have taken into account previous papers, including those of Guo's group. In addition the sedimentological model we proposed is new due to the lack of previous sedimentological studies, including facies analysis and petrography, in the studied area. Our model of a continental alluvial-lacustrine basin fits well with other well-known examples over the world and explains clearly the lateral facies transitions across the basin. It is not the aim of this reply to discuss all the previous papers by Guo's group, but to reply to their main comments on our paper. © 2010

Ferroelectric copolymer thin films P(VDF-TrFE) are used as a ferroelectric cathode for investigation of their electron emission properties. This ferroelectric copolymer films with different thicknesses are deposited by spin-coating method, and then the annealing process is carried out to improve the crystallinities of as-deposited copolymer films. The measurement results of ferroelectric electron emission showed that the copolymer P(VDF-TrFE) films had a desired ferroelectric electron emission ability excited at low-voltage pulse, and its peak emission current can reach to be ∼1.3 μA when the pulse voltage is 280 V. In addition, the effect of film thickness on electron emission property and emission stability of copolymer thin film P(VDF-TrFE) are discussed.

The following thesis makes a thorough analysis on the relationship between customer value and quality management system by introducing the concept of customer value management into the field of quality management. The author puts forward the idea that customer value is the goal of quality management system, while quality management system is the guarantee for customer value. Customer value directs the way for the innovation of quality management system.

Heavily boron-doped diamond films are synthesized by the hot-filament chemical vapor deposition method under the gas mixtures of H2, CH4 and trimethyl borate. The measurement results of scanning electron microscopy, Raman spectroscopy, X-ray diffractometer and electrical properties showed the morphologies, microstructures, carrier concentration and superconducting transition temperature for as-grown diamond films were dependent on the change of growth pressure, and specially its carrier concentrations could be adjusted from 1019 to 1021 cm−3 by increasing growth pressures from 2.5 to 5 kPa. And further, the effects of growth pressure on the film microstructural property and the doping level dependence of the superconducting transition temperature were discussed.

Aiming at the reuse of design knowledge, this paper proposes knowledge reuse technology for product design of printing press which is based on rule and case. An integrated software package with SQL Server which is Database Management System (DBMS) and VisualC++6.0 which is a kind of development tools has been developed. This software may be embedded in the environment of Solidworks to assist the designer to index correlative design knowledge and develop new product of printing press after modification.

The hydrogenation of Ib-type single crystalline diamond with grain size of several tens of micrometers, synthesized by high-pressure and high-temperature (HPHT) sintering, was carried out by hydrogen plasma treatment in a hot-filament chemical vapor deposition (HFCVD) system. After exposure to air, the surface conductivity of (001) and (111) facets of HPHT single crystalline diamond was measured. The influences of hydrogenation duration, temperature and gas pressure on the surface conductivity of (001) and (111) facets have been investigated. The measurement results show that the variation of hydrogenation conditions has a noticeable effect on the surface conductivity of single crystalline diamond, which is closely related to the formation of a chemical vapor deposition (CVD) regrowth layer on the facets induced by hydrogen plasma treatment process. In addition, (001) surface exhibits higher electrical conductivity than (111) surface, which is mainly attributed to less nitrogen concentration on the (001) surface than on the (111) surface.

Highly (0 0 2)-oriented AlN film was deposited on n-type (1 0 0)-oriented silicon substrates by the radio frequency magnetron sputtering method. An individual AlN cone with high aspect ratio was fabricated by the focused ion-beam (FIB) etching process in the surface of an as-formed AlN film. This etching method can easily control the tip radius and height to obtain AlN cones with different aspect ratios. The field-emission property of the individual AlN cone was measured in a scanning electron microscopy system equipped with a movable probe as the anode above the AlN tip. The results indicated that the as-formed single AlN cone with high aspect ratio possessed good field-emission ability although it only had a tiny emission area. Compared with a single Si tip fabricated by the same method, a single AlN cone exhibits better field-emission ability, and hence, has great potential as a promising candidate of point electron source for application in vacuum electronic devices.

A 2-D optical scanner was developed for the imaging and quantification of up-converting phosphor (UCP) labels in immunoassays. With resolution better than 500 microm, a scan rate of 0.4 mm/s, and a 1-2% coefficient of variation for repeatability, this scanner achieved a detection limit of fewer than 100 UCP particles in an 8.8. x 10(4) microm(2) area and a dynamic range that covered more than three orders of magnitude. Utilizing this scanner, a microfluidic chip immunoassay for the cytokine interferon-gamma (IFN-gamma) was developed: concentrations as low as 3 pM (50 pg/mL) were detected from 100 microL samples with a total assay time of under an hour, including the 8 min readout. For this UCP-based assay, 2-D images of the capture antibody lines were scanned, image processing techniques were employed to extract the UCP emission signals, a response curve that spanned 3-600 pM IFN-gamma was generated, and a five-parameter logistic mathematical model was fitted to the data for determination of unknown IFN-gamma concentrations. Relative to common single-point or 1-D scanning optical measurements, our results suggest that a simple 2-D imaging system can speed assay development, reduce errors, and improve accuracy by characterizing the spatial distribution and uniformity of surface-captured optical labels as a function of assay conditions and device parameters.

Bulk quantity and long-scale amorphous SiO2 nanowires have been prepared simply by direct pyrolysis of an iron-modified perhydropolysilazane (Fe-PHPS) at 1300 °C in the flowing Ar atmosphere. Scanning electronic microscope (SEM) study shows that most SiO2 nanowires have smooth surface and they consist of straight and smoothly curved parts, with diameters in the range of 50 to 200 nm and lengths up to 200 μm. Beside this normal form of SiO2 nanowires via the typical vapor-liquid-solid (VLS) mechanism, four other different helical forms of nanowires, named spring-shaped nanowires, twinborn nanospring, fishbone-shaped nanowires and braided-like helical SiO2 nanowires, are also observed. The formation of these nanowires is proposed to be the modulated contact angle anisotropy (CAA) mechanism based on the VLS mechanism.

Polysiloxane–polyester copolymers have been synthesized for the first time by direct polycondensation of a series of diacids (butanedioic, hexanedioic, and octanedioic acid) and α,ω-bis(3-hydroxypropyl) polydimethylsiloxanes catalyzed with Novozyme-435 in high yields (>90%) without the cleavage of SiO bonds. The effects of monomer chain length, reaction temperature, and water removal method on the number–average molecular weight (Mn) of the resulted copolymers were investigated. Thermogravimetric and differential scanning calorimetry analyses indicated that the produced copolymer was more thermally stable than poly(1,8-octyladipate) and the Tg was lowered to −111°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

A stable superhydrophobic surface was fabricated by solidifying poly(epoxy-terminated polydimethylsiloxane- co -bisphenol A) [P(ETPDMS- co -BPA)] copolymer on a rough substrate. The low surface energy of the copolymer and the geometric structure at micrometer scale of the surface contribute to the superhydrophobic property. The as-prepared surface shows stable superhydrophobicity over a wide pH range (1–14) and the wettability is excellent stable to heating, water, corrosive solution and organic solvent treatments. The procedure is simple and time-saving as well as utilizing non-fluorine-containing compounds.

The information of coal-bed distribution, rank and gas-bearing nature of Jurassic coals in eastern Junggar basin were analyzed, and the controlling factors of coal-bed methane (CBM) accumulation were pointed out, which were coal rank, coal seam depth, and preservation conditions. The most important factor was depth of weathered zone of methane and coal rank. Consequently, Badaowan formation in Bogeda piedmont and Jimusaer depression and coal bed of Xishanyao formation in Wutongwozi depression were identified as the enriched areas of CBM in eastern Junggar basin. In a word, the Bogeda piedmont would be the main target for exploration in this area.

This paper aims at the problems and countermeasures of cathodic protection acceptance of the Yili River crossing project by horizontal directional drilling (HDD) method, addressing the performability of the acceptance criteria using polarization potential offset of not less than 0.7V required by the Kazakhstan Owners. Polarization potential and depolarization potential measurements as well as coating resistance measurements have been carried out based on the methods and requirements specified in NACE and ISO standard. The results show that protection coating has been damaged in the process of the HDD implement and cathodic protection system can protect the steel exposed, and that the polarization potential offset of not less than 0.7V required by the Owner cannot be met even the protection potential within the protection criteria specified in the design document. Finally, polarization potential offset of not less than 0.33V has been agreed on by all parties for the acceptance of HDD pipe section. Keywords-yili river; horizontal directional drilling crossing; cathodic protection

New forms of tubular carbon cone (TCC) were grown on gold wires by hot-filament chemical vapor deposition (HFCVD). They have a long-cone-shaped appearance with a herringbone hollow interior, surrounded by helical sheets of graphite that are coiled around it. It is considered that TCC formation results because the size of the catalyst particle located in the top of the TCC decreases continuously during growth, due to etching effects in the CVD plasma, reflecting competition between the growth and etching processes in the plasma. In addition, field emission measurements show that TCCs have a very low-threshold field of 0.27 V/mu m, and that a stable macroscopic emitting current density of 1 mA/cm(2) can be obtained at only 0.5 V/mu m. TCCs have good field emission properties, compared to other forms of carbon field emitter, and may be good candidates for use in field emission display devices. (C) 2007 Elsevier B.V. All rights reserved.

Diamond cone arrays were formed by plasma etching of diamond films in a hot filament chemical vapor deposition (HFCVD) system. The role of CH4 in the formation of diamond cone arrays was investigated. It was found that addition of CH4 to H2 plasma could enhance the plasma intensity and hence the etching efficiency to improve the formation of diamond cones with high aspect ratio and controllable density. The microscopic measurement of the as-formed diamond cones shows that they have an inner core of polycrystalline structure and an outer layer of amorphous carbon. These as-formed diamond cones have exhibited field emission current density of 1 μA/cm2 at threshold field of 5 V/μm. For an applied field of 12 V/μm, the emission current density can rapidly reach as high as 560 μA/cm2. The property of high field electron emission is attributed to the high aspect ratio of as-formed diamond cones and the appropriate cone density as well as the outer amorphous carbon layer which acts as a pathway for electron-hopp...

Iron-containing polysilazanes (PSZI) were prepared by the amine displacement reaction along with heat-induced vinyl crosslinking reactions between Fe[N(SiMe2Vi)2]3 (Vi = CHCH2) and polysilazane containing SiVi (PVSZ). The PSZIs were converted into magnetic ceramics by the pyrolysis in N2. The ceramics produced were investigated by X-ray diffraction, transmission electron microscope and vibrating sample magnetometer at room temperature. It was indicated that α-Fe is the only magnetic crystalline embedded in the amorphous Si/C/N-based matrix from 500 to 900°C. Moreover, the sample prepared at 500°C showed few hysteresis at room temperature, consistent with the behavior of superparamagnetic particles, which was confirmed by the zero-field-cooled and field-cooled magnetization measurement. Additionally, the results indicated that the magnetic properties of the ceramics could be tuned by controlling the content of iron and the pyrolysis temperature. This flexibility may be advantageous for some particular magnetic materials applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

A natural preservative from white mustard (Sinapis alba) has been developed under the brand name IsoGard . The essential oil is extracted from moistened, ground white mustard seeds by supercritical fluid extraction. Grinding the wet seeds activates the enzyme myrosinase, which hydrolyzes the glucosinolate (sinalbin) naturally present in white mustard seeds, to yield the active anti-microbial agent, 4-hydroxybenzyl isothiocyanate (4HBITC). The essential oil contains ∼25-35% by weight of 4HBITC. Microbial challenge studies have demonstrated that IsoGard is an effective anti-microbial agent at relatively low usage levels. Challenge tests in an acidified fruit drink against gram-negative, acid-tolerant bacteria (Gluconobacter species) and preservative-resistant yeast (Zygosaccharomyces bailii) showed that a 4HBITC concentration of 25 mg L -1 was sufficient to stabilize the product for 28 days against microbial growth at ambient temperature. A bactericidal study in neutral pH peptone broth under refrigerated conditions (6.5°C), demonstrated that IsoGard acts against various pathogenic and spoilage bacteria, including Escherichia coli, Staphylococcus aureus, Campylobacter jejuni, Pseudomonas aeruginosa, Salmonella enteritidis, Listeria monocytogenes, Shigella boydii, and Clostridium perfringens. 4HBITC concentrations of 60-120 mg L -1 produced a 2-4 log reduction in microbial counts while 360 mg L -1 gave a > 6 log reduction. When injected into beef steaks as part of a brine, an initial 4HBITC concentration of 46 mg L yielded a one log reduction in aerobic plate count (28 days, 5-10°C). To dispense low levels of the anti-microbial into foods and to stabilize the 4HBITC, which is unstable in the presence of water, different IsoGard formulations have been developed. The active compound contributes a mild heat sensation to food products that are tasted fresh. The heat dissipates during storage or cooking of the product as the 4HBITC is hydrolyzed in the presence of moisture. IsoGard has future potential as an all-natural preservative.

Magnetron sputtered carbon nitride films (CNx) were annealed at 750 degrees C for periods from 30 to 120 min. Effects of annealing with different durations on the field emission of CNx films were investigated and related to the variations of chemical bonding and surface morphology induced by annealing. The results show that annealing effectively enhances field emission ability of the CNx films and that the threshold field was lowered from 13 to 5 V/mu m. The measurements of Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) indicated that annealing leads to a loss of N content and to formation of more graphite-like sp(2) C clusters in the films, and simultaneously the film surface becomes rougher after annealing, all of which is attributed to the increased film field emission. A large number of sp(2) C clusters with good conductivity enables tunneling in the film, making electron emission easier, and moreover, a rougher surface also improves the field enhancement factor of the films. However, continuing to increase annealing time eventually lowers the field emission of the films. (c) 2005 Elsevier B.V. All rights reserved.

Thermal and dynamic mechanical properties of carbon dioxide and propylene oxide alternative copolymer, poly(propylene carbonate) (PPC), and the end-capped PPC with maleic anhydride were investigated by means of TG and DMA. A master curve of the storage modulus vs. frequency can be deduced from the isochronal curves. Physical parameters of both plain and MA end-capped PPC were discussed. The results showed that for maleic anhydride (MA) end-capping PPC, an improvement of its thermal stability and mechanical properties accompanied with some modifications of the viscoelastic behavior were obtained.

Silicon nanocone arrays are formed on porous silicon substrates by plasma etching in a hot filament chemical vapour deposition system. The as-formed Si nanocones were characterized by means of scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Raman spectroscopy. The results indicate that the nanocone is composed of a silicon core coated with a thin amorphous carbon (a-C) layer produced by carbon-bearing plasma etching. Plasma etching is a key factor in the formation of the nanocone arrays, while re-condensation of evaporated silicon atoms on the tip of the as-etched cone also occurs. Field emission measurements show that the a-C coating can effectively enhance the field emission ability of the nanocone arrays due to the decrease of the surface work function from 4.15 to 2.37 eV.

Effect of annealing on the field emission properties of diamond-like carbon (DLC) films deposited by high power excime laser technique was studied. Raman spectrometry and X-ray photoelectron spectrometry (XPS) were used to determine the chemical bonding structural change of the annealed DLC films. It was found that the annealing transformed gradually DLC films into a graphitic structure as annealing temperature was increased to more than 600 degrees C, simultaneously field emission properties of DLC films were enhanced markedly. Graphitization of DLC films induced by annealing caused the formation of a large fraction of sp(2) C in the DLC films, which played an important role in the enhancement of field emission properties for DLC films. Rich sp(2) C cluster acted as a conduction part in the films could increase the conductivity of DLC films and lower the effective work function of DLC films, consequently improve field emission properties of DLC films. (c) 2005 Elsevier B.V. All rights reserved.

Amorphous hydrogenated germanium-carbon (a-Ge1xCx:H) films were deposited by RF reactive sputtering pure Ge (1 1 1) target at different flow rate ratios of CH4/(CH4+Ar) in a discharge Ar/CH4, and their composition and chemical bonding were investigated using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). XPS and FTIR results showed the content of germanium in the films decreased with the increase of the flow rate ratio CH4/(Ar+CH4), and the Ge–C, Ge–H, C–H bonds were formed in the films. The fraction of Ge–C, Ge–H, and C–H bonds was strongly dependent on the flow rate ratio. Raman results indicated that the films also contain both Ge–Ge and C–C bonding. Based on the change of the chemical bonding of a-Ge1xCx:H films with the flow rate ratio CH4/(CH4+Ar), an optimal experimental condition for the application of infrared windows was obtained.

The crystallization and melting behavior of poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) (PHBV) and a 30/70 (w/w) PHBV/poly(propylene carbonate) (PPC) blend was investigated with differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR). The transesterification reaction between PHBV and PPC was detected in the melt-blending process. The interaction between the two macromolecules was confirmed by means of FTIR analysis. During the crystallization process from the melt, the crystallization temperature of the PHBV/PPC blend decreased about 8 degreesC, the melting temperature was depressed by 4 degreesC, and the degree of crystallinity of PHBV in the blend decreased about 9.4%; this was calculated through a comparison of the DSC heating traces for the blend and pure PHBV. These results indicated that imperfect crystals of formed, crystallization was inhibited, and the crystallization ability of PHBV was weakened in the blend. The equilibrium melting temperatures of PHBV and the 30/70 PHBV/PPC blend isothermally crystallized were 187.1 and 179 degreesC, respectively.

Magnetron sputtered amorphous carbon nitride films were annealed at different temperatures (450–900°C) and time (30–120 min). Compositional, bonding structural and surface morphological modifications of the films were characterized by Fourier transformation infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy. The as-deposited film was found to have nitrogen content of 30 at%, and the carbon atoms were bonded to nitrogen atoms in the chemical structure state of CN, CN and CN bonds. The FTIR and XPS results showed that the films were thermally stable without an obvious change in the films as annealing temperature was lower than 600°C. The relative intensity ratio of CN over CN bonds reached a maximum at annealing temperature of 750°C, and then decreased gradually at annealing temperature up to 900°C. The CN bonds in the films decreased with the increase of annealing temperature and eliminated completely at annealing temperature of 900°C. These results revealed that annealing caused a substantial decrease in the number of weak bonds between carbon and nitride atoms. The CN bonds have higher thermal stability than CN bonds and CN bonds in the films. Simultaneously annealing also led to the formation of a large fraction graphitic-like carbon in the films while nitrogen escaped from the film. Besides, the surface roughness of the films increased with annealing temperature. However, when annealing time was increased from 30 to 120 min at annealing temperature of 750°C, only a slight effect of the annealing time on composition, bonding structure and the surface roughness of the films was observed.

In this paper, the configuration of the sub-reflector adjustment mechanism of Shanghai 65 meters radio telescope is introduced, and the kinematics calibration is performed by the laser tracker for institutions. Secondly, based on the strong coupling characteristics of the parallel mechanism, a method contains a coupled repeated positioning accuracy information is proposed which is suitable for the parallel mechanism repeated positioning accuracy measurement and evaluation. Finally, according to the proposed repeated positioning accuracy measurement and evaluation methods, the uniaxial repeated positioning accuracy and spatial pose repeat precision of the adjustment mechanism of sub-reflector are measured and analysed. The results show that the repeated positioning accuracy of the adjustment mechanism of sub-reflector is high and is able to meet the requirements of the pointing adjustment precision of the sub-reflector of 65 meter radio telescope.

Pipelines in more undulated areas are likely to have crossing points in pipeline transportation as oil throughput varies. This is to say that the potential energy of oils, from the peak to the terminal, is possibly higher than energy required for overcoming friction factor in oil movement, thus producing slack flow in pipes after the peak and accelerating partial flow velocity to consume remaining energy. Existed slack flow will be problem-prone like increased surge pressure, slow response to post-peak accident and vibration incurred by repeated occurrence and collapse of the steam bubble, when there are separation and crash of the liquid column in sudden change of the liquid flow speed. Therefore, targeted measures are necessary for avoiding slack flow. This text, for the first time, develops a parameter calculation model based on mechanism and characteristics of slack flow, proposes technology of predicting characteristics of the slack flow of pipelines in hilly areas with large fall and correctly predicts the defined parameters for the slack flow, including position, length, steam space volume, air space ratio and oil flow speed. Keywords-large fall; slack flow; oil pipeline; mechanism; characteristic parameter

Semiconductor nanoparticles (quantum dots) were studied in the context of liquid scintillator development for upcoming neutrino experiments. The unique optical and chemical properties of quantum dots are particularly promising for the use in neutrinoless double beta decay experiments. Liquid scintillators for large scale neutrino detectors have to meet specific requirements which are reviewed, highlighting the peculiarities of quantum-dot-doping. In this paper, we report results on laboratory-scale measurements of the attenuation length and the fluorescence properties of three commercial quantum dot samples. The results include absorbance and emission stability measurements, improvement in transparency due to filtering of the quantum dot samples, precipitation tests to isolate the quantum dots from solution and energy transfer studies with quantum dots and the fluorophore PPO., version 2, minor text updates

We report on three different experiments on high temperature superconducting (HTS) cuprates and colossal magnetoresistive (CMR) manganites, which clearly bring out some of the important similarities and differences between the two material systems. The experiments involve the measurement of temperature dependence of the mean squared displacement of Cu and Mn ions from their equilibrium site in the case of the cuprates and the manganites, respectively, and their correlation with the transport property. In both cases the key ions in the materials (Cu for HTS and Mn for CMR) exhibit vibration amplitudes larger than that of ions in simple Debye solids and clearly show discontinuities in the vibration amplitudes as a function of temperature close to the phase transition temperatures. These point to the unequivocal participation of phonons in the transport processes and possibly in the onset of the phase transitions (i.e. superconductivity and ferromagnetism). The second set of experiments, involves femtosecond optical excitation of micro-strip resistors made of cuprates or manganites, and the subsequent measurement of the changes in the impedance on a 20 ps time scale. In the case of the manganites one measures the time scales involved in the ionization and reformation of a Jahn-Teller polaron and also the decay times of magnon excitors. In the case of the cuprates one sees a highly efficient pair breaking process with a very sharp resonance, with a width of only 100 meV, which is indicative of the role of a large intermediate excitation in the mechanism of high temperature superconductivity. In the third experiment, spin-polarized electrons injected from a manganite electrode into a superconductor are observed to break pairs at a rate far larger than unpolarized electrons. This effect seems very orientation dependent for the case of YBCO, which may shed new light on the transport of quasi-particles at YBCO interfaces.

O005 RETREATMENT OF PATIENTS WHO FAILED 8 OR 12 WEEKS OF LEDIPASVIR/SOFOSBUVIR-BASED REGIMENS WITH LEDIPASVIR/SOFOSBUVIR FOR 24 WEEKS E. Lawitz, S. Flamm, J.C. Yang, P.S. Pang, Y. Zhu, E. Svarovskaia, J.G. McHutchison, D. Wyles, P. Pockros. Texas Liver Institute, University of Texas Health Science Center, San Antonio, TX, Feinberg School of Medicine, Northwestern University, Chicago, IL, Gilead Sciences, Foster City, CA, University of California, San Diego, CA, Scripps Clinic, La Jolla, CA, United States E-mail: jenny.yang@gilead.com

The loess/paleosol sequence in loess layer L1 (Malan Loess) is investigated in three regions of the Western Chinese Loess Plateau. Nine pedogenic layers are found in L1 and three proxy climate indices, magnetic susceptibility (MS), grain size (GS) and CaCO3 content, are measured at intervals of 0.2 kyr in order to recover records of monsoon climate variations. Time series of MS, GS and CaCO3 content document the high resolution history of summer and winter monsoon climate variations over the last 75 kyr. The records show a high degree of similarity to the warm interstadials recorded in ice cores from Greenland and the Antarctic, and with Heinrich events in the North Atlantic, during the last glacial cycle. Bond cycles are also recorded by the Chinese loess records. Overall, our results indicate that numerous rapid changes in climate occurred in China during the last glacial cycle, but that the range of climate variations was smaller than recorded in Greenland.

Long-term treatment with cyclosporine A (CsA) is associated with various types of complications; however, CsA-induced anemia has not been reported. The present study examined the impact of CsA on hematopoietic parameters and intrarenal expression of erythropoietin (EPO) and the EPO receptor (EPOR) in a rat model of chronic CsA nephrotoxicity. Sprague-Dawley rats were fed a low-salt diet (0.05% sodium) and were treated daily for 4 weeks with vehicle (olive oil 1 mL/kg subcutaneously) or CsA (15 mg/kg subcutaneously). The expression of EPO and EPOR was evaluated by immunohistochemistry and immunoblotting, and hematopoietic parameters were assessed by measuring blood hemoglobin and hematocrit levels, and these variables were compared between treatment groups. Renal function, oxidative stress, histopathology (tubulointerstitial fibrosis), apoptotic cell death, and expression of transforming growth factor β-inducible gene-h3 (βig-h3) were also compared between treatment groups. In kidneys from vehicle-treated rats, endogenous EPO and EPOR protein were expressed constitutively in the outer stripe of the outer medulla and the cortex. EPO protein expression decreased significantly in kidneys from CsA-treated rats. By contrast, EPOR expression was higher in kidneys from CsA-treated rats than in vehicle-treated rats. These changes were accompanied by decreases in serum hemoglobin and hematocrit levels and correlated with the number of cells positive for terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (r = -0.769, P = .003) and βig-h3 protein expression (r = -0.910, P < .001). Long-term treatment with CsA suppresses renal endogenous EPO expression, resulting in anemia. Increases in apoptotic cell death and βig-h3 expression are closely associated with inhibition of EPO expression in chronic CsA nephrotoxicity.

Active power filters are widely applied in power system to deal with distorted currents caused by nonlinear loads. As the active power filter (APF) with LCL filter is a serious nonlinear system, conventional control methods cannot have satisfactory performances. A nonlinear control method, backstepping control for active power filter with LCL filter is proposed in the paper. The control adopts backstepping method to design feedback control law based on the state space average model of APF. While introducing virtual control and forming Lyapunov function step by step, the nonlinear controller with global asymptotic stability is obtained at last. Compared with conventional local linearization methods, backstepping method does not ignore any high order nonlinear terms and maintain global system nonlinearity. Thus the proposed control method achieves better control effects such as suppressing LCL resonance without additional passive or active damping. Finally, simulation in MATLAB and experimental results on a 20kVA prototype verify the feasibility and stability of proposed control method.

A new scheme of low-power temperature and humidity monitoring system base on wireless sensor network (WSN) is proposed to overcome the weakness of the ones at present. In this paper, a star topology is used as the structure of network, and the microcontroller unit (MCU) as the main control device in base station and slave stations. Slave stations use SHT11 digital temperature and humidity sensor to complete data acquisition, and exchange data with base station by low-power multi-channel nRF905 transceiver chip. This paper introduces the hardware and software of the base station, using the communication protocol and frequency hopping (FH) mechanism to ensure the reliability of data transmission, increasing the robustness of the system. The result shows that this system has the advantage of portable, flexible arrangement, a large coverage area, low power consumption, and small disturbance, etc. The design is worth to be applied in practical applications.

Dielectric oxides are traditionally used to fabricate resistive surface humidity-sensing devices, as well as capacitive sandwich-structured sensors. In the present work, relative humidity (RH) sensors were fabricated by employing vertically aligned TiO(2) nanotubes array (TNA) film produced using electro-chemical anodization of Ti foil followed by a nitrogen-doping process, simultaneously showing resistive and capacitive humidity-sensing properties in the range of 11.3-93.6%. For the sample formed at optimized experimental conditions, the capacitance (C(S)) and resistance (R(S)) of the as-fabricated RH sensors made from nitrogen-doped TiO(2) nanotubes film could be simultaneously obtained. Both the resistive and capacitive sensitivity (K(R) and K(C)) of the as-fabricated TiO(2) nanotube RH sensors show distinct dependence on the frequency of alternating current (AC) voltage signal and RH. At higher water coverage, water-water interaction will result in lowering of the water dissociation barrier, leading to an increase of conductance. With the increase of RH, the polarization of as-adsorbed water molecules will also occur, causing a sharp increase of capacitance. For an explanation of the frequency response of both C(S) and R(S), ionic transport, as well as the polarization effect, should be comprehensively considered. The changes of capacitance and resistance at different temperatures are plausibly caused by thermal expansion and surface state modification by adsorption and desorption of oxygen and water.

Ferroelectric copolymer thin film PVDF-TrFE was deposited by spin coating method, and then annealed for the improved crystallization. The XRD and AFM measurements showed that as-formed PVDF-TrFE thin film was composed of the nanocrystallines with 50-80 nm in size and some amorphous phases. Meanwhile, as-formed PVDF-TrFE thin films also show a good polarization inversion property with a switch current of approximately 2.0 microA at a coercive field 40 MV/m. Electron emission testing results showed that under a continuous excitation of applied voltage pulses, PVDF-TrFE thin films exhibited an expected electron emission ability with emission current range of 0.08-0.52 microA, and the related electron emission mechanism was discussed.

Tubular carbon cones (TCCs) with a herring-bone-like graphitic structure are synthesized on gold wire via the bias-assisted hot filament chemical vapor deposition (HFCVD) method. The electrical transport properties of an individual TCC are studied in the temperature range from 300 to 500 K by using a double probe scanning electron microscopy (DPSEM) in situ electrical measurement system. The high-resistance I-V characteristics of W-TCC-Au back-to-back double junctions show that electrons tunnel through the W-TCC junction, while thermoionic transport through the Au-TCC junction contributes to low-resistance properties. Temperature dependence of the electrical characteristics indicates that inter-graphitic-plane electrical transport in TCC is metallic.