bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Interdiffusion of Hauling Theory between Dissimilar Polymers Based on Novel USW
Authors: Zhang Guo Hong , Qiu Jian Hui , Shao Liang , Fu Xie
Published: March 2011

Based on the novel USW method, the welds of Polylactide (PLA) - Polyformaldehyde (POM) and PLA - polymethyl methacrylate (PMMA) have been carried out. The interdiffusion processes of polymer chains have also been investigated according to the reptation theory and the hauling theory. The welding strengths are carried out by the universal tester and the rupture interfaces are observed using the scanning electron microscope. The best welding strength is 52MPa (90% compared with PLA of the PLA-POM system), which can reach the tensile strength of IPS. The molecules of POM are much easier to inter-diffuse than those of PLA and PMMA.
Preparation of Antibacterial Cotton Fabric Containing Patchouli Oil Microcapsules by Chemical Crosslinking Method
Authors: Yang Zi Ming , Liang Gen Quan , Li Ly , Au Wai Man , Zhong Hui Yi , Wong Thomas K.S. , Yang Zhuo Hong
Published: March 2011

In this paper, a new kind of antibacterial cotton fabric containing patchouli oil microcapsules was investigated. The patchouli oil microcapsules were prepared using a complex coacervation procedure and grafted onto cotton fabric by chemical crosslinking method, along with 1,2,3,4-butanetetracarboxylic acid (BTCA) was utilized as the crosslinking agent. The surface and morphology of fabrics were characterized by using scanning electron microscope (SEM). Fourier transform infrared spectrometry (FTIR) was used to study the formation of ester bonds between BTCA and hydroxyl groups of cotton and patchouli oil microcapsules. The releasing characteristics and antimicrobial durability of the antibacterial fabrics were also investigated by releasing test and laundering test. The results showed that the patchouli oil microcapsules were grafted onto cotton fabric by the role of crosslinking agent BTCA and the treated fabric represented persistent effect, slow releasing performance and washable antibacterial properties. After 30 days, the patchouli oil in the microcapsules was still remained on the fabric and the releasing amount was near 50%. About 72% antibacterial rate of the fabric for staphylococcus aureus and candida albicans could be obtained after washed 30 times, furthermore, no formaldehyde releasing can be found. It is suggested that chemical crosslinking method would provide a potential application in functional finishing by microcapsules for cotton fabric.
Study on the Effect of Thermal Design of Plane Mould on the Mechanical Properties of Epoxy Sheet Molding Compounds
Authors: Li Jian , Huang Zhi Xiong , Jin De Liang
Published: March 2011

The heating style of the plane mould has great influence on the mechanical properties of E-SMC parts. In this paper, the temperature distribution of the plane mould (general heating style and thermal optimized heating style) and the mechanical properties and the cross section morphology of E-SMC samples were systematically studied. The results showed that there existed 30°C difference between the highest temperature point and the lowest temperature point in the general heating mould cavity, the difference of flexural strength between the samples cut from the centre and those cut from the corner was about 140MPa, otherwise, the fiber distribution of the fracture cross section was extremely uneven and the fibers were poorly adhered with epoxy resin. While, in the thermal optimized mould cavity, the surface temperature was much more even and the difference between the highest temperature point and the lowest temperature point was less than 10°C. And the flexural strength between the samples cut from the centre and those cut from the corner was close to be 320MPa. The fiber distribution of the fracture cross section was even and the fibers were well adhered with epoxy resin.
Liquid-State Synthesis and Properties of Fluorescent Conducting Polymers: α, βi-SiW11GaIII/Polyaniline
Authors: Yang Wan Li , Lv Ren Jiang , Ma Rong Hua
Published: March 2011

Four polyaniline hybrid materials were prepared by liquid-state synthesis method in the presence of dopant which synthesized by transition metal mono-substituted Keggin structure silicotungstate anions α, βi-[SiW11Ga(H2O)O39]4-. The polyaniline hybrid materials were characterized by elemental analysis, IR spectroscopy, fluorescence spectroscopy, scanning electeon microscopy (SEM) and thermo gravimetric analysis, the properties of which such as thermal stability and conducting behavior were studied. It proved that the average diameter was 100nm, the conductivity was 9×10-2s•cm-1 and the flourescence property was better.
End-Point Control of Holding Phase Based on Cavity Pressure for Injection Molding
Authors: Wang Jian , Xie Peng Cheng , Yang Wei Min
Published: March 2011

While the switchover from filling to packing is particularly crucial during injection molding, the transfers from holding to screw recovery also significantly affects the quality of molded parts. In this study, the end-point control of the holding phase based on cavity pressure was presented. It was compared with the traditional control method by holding time. The purpose of this study was to validate the feasibility of the end-point control of holding phase by cavity pressure, and to examine its consistency. The weight of the molded parts served as the main measure to probe the process’s capabilities. The results of the verification experiments revealed that the end-point control mode based on cavity pressure could yield better consistency of part weight than the traditional control method by holding time, however, the benefits were not significant. The trigger value of cavity pressure and sensor position should be considered for achieving such high process capabilities.
Preparation and Characterization of PVDF Hydrophobic Membrane
Authors: Zhang Hua Feng , Zhang Yu Zhong , Lin Li Gang , Ding Xiao Li , Li Hong
Published: March 2011

Polyvinylidene fluoride (PVDF) hydrophobic membrane has been prepared by phase inversion method. The effects of concentration of PVDF, different processes of preparations, and different surface roughness on hydrophobic capability of membrane surface (water contact angle, WCA) have been investigated. The results showed that, hydrophobic ability of PVDF membranes decreased with the increasing concentration of PVDF. WCA of membrane prepared by was increasing. Membrane surface hydrophobic ability increased with the increasing surface roughness. The contact angle of membrane comes to 141° with dry process and 10% PVDF concentration.
Effects of Rotor Speed on Manufacturing Process of Short Fiber-Rubber Composite Material
Authors: Zhang De Wei , Wang Chuan Sheng , Lin Guang Yi
Published: March 2011

Rotor Speed is an important factor which impacts the mixing process and quality of mixed rubber greatly. The effects of different rotor speeds on manufacturing process of short fiber-rubber composite material have been studied by experimental study. In the experiments, the rotor speeds were 50rpm, 60rpm, 70rpm and 80rpm respectively. The experimental results indicated that the mixed rubber after vulcanized had better physical and mechanical properties as the rotor speed was 70rpm. So the rotor speed that is 70rpm has been chosen for manufacturing short fiber-rubber composite material.
Experimental Research and Performance Testing of Fe-Based Composite Plating
Authors: Fu Ping , Zhao Cheng , Tian Hua
Published: March 2011

By using self-made asymmetric AC - DC power supply and adding SiC in ferrous chloride bath, the high performance Fe-SiC iron-based composite coatings were prepared by electrodeposition method. The effect of Phase, composition and SiC particle content on the surface morphology, structure, hardness, wear resistance and corrosion resistance of Fe-SiC composite coatings were studied. The process parameters of Fe-SiC composite plating were optimized. The results showed that the micro-cracks in composite coatings would reduced and the hardness, wear resistance and corrosion resistance will increased by adding SiC particles under the condition of optimum process.
Preparation and Characterization of PES/SPSF Blend Ultrafiltration Membrane
Authors: Ma Feng , Zhang Yu Zhong , Ding Xiao Li , Lin Li Gang , Li Hong
Published: March 2011

Polyethersulfone(PES)/Sulfonated polysulfone(SPSF) blend ultrafiltration membranes at different SPSF contents were prepared using a phase inversion technique. The morphological structures of PES/SPSF blend ultrafiltration membranes with different sulfonation degree were characterized using SEM. The results shown that the PES/SPSF blend ultrafiltration membranes had good retention to PEG1000 (99.8%) and high water permeate flux (27.2Lm-2h-1) at 0.1MPa.
Experimental Study on Thermal Conductivity Property of Rubber Composites Filled with Carbon Nanotubes
Authors: Wang Ze Peng , He Yan
Published: March 2011

Thermal conductivity of rubber composites filled with CNTs (carbon nanotubes) and N234 CB (carbon black) were investigated. Result indicated that Thermal conductivity of NR (natural rubber) filled with CNTs is higher than that of NR filled with CB in the case of the same filling amount. CNTs can better improve the performance of thermal conduct of rubber composites than CB. The more the filling content of CNTs is, the higher thermal conductivity of NR composites.
Nonlinear Finite Element Analysis of the Bending of Shape Memory Alloy Hybrid Epoxy Beams
Authors: Sun Shuang Shuang , Jiang Xian Ce , Sun Guo Jun
Published: March 2011

On the basis of considering the thermo-viscoelasticity of the epoxy matrix, the geometrically nonlinear finite element formulation is developed to simulate the moderate deflection bending of the shape memory alloy (SMA) hybrid beam upon actuation of SMA. It is found that the midpoint deflection of the epoxy beam increases with increasing temperature when temperature is lower than the austenite start temperature of SMA. Once the austenite start temperature of SMA is reached, the midpoint deflection of the epoxy beam is rapidly decreased to the initial state with the increasing of temperature. And then it increases slowly with increasing temperature after the austenite phase transformation of SMA is finished. The results based on the geometrically nonlinear finite element analysis are also compared with those from the geometrically linear finite element analysis, which shows that they agree well with each other when the bending deflection of the epoxy beam is small, while significant discrepancies occur between them when the deflection is considerably large.
Distributive Mixing Performance and Mixing Efficiency of Discs in a Series Disc-Screw Extruder
Authors: Yang Jing , Jiang Bo
Published: March 2011

This work aims at the simulation of three-dimensional isothermal flow between a pair of discs in series disc-screw (SDS) extruder by computational fluid dynamics. To analyze the distributive mixing performance and overall efficiency of discs, mixing parameters such as segregation scale and time-average efficiency were calculated. The effects of the disc configuration and the distance between a pair of discs on the distributive mixing were discussed. The more grooves on the disc, the better distributive performance. Good distributive mixing performance can be obtained by big gaps.
The Dynamics Analysis of Rolling Movable Teeth Reducer
Authors: Wu Jun Fei , Zhu Xiao Chen , Gao Wei , Yu Ying
Published: March 2011

The structure and operating principle of rolling movable teeth reducer are introduced in this paper. Through the virtual prototype technology, the modeling of rolling movable teeth reducer is made by Pro/E software,and is had the kinematics simulation and dynamic analysis by ADAMS software. The simulation results show that the speed curves of the input shaft and the output shaft of rolling movable teeth reducer coincide with the theory transmission. It proves correctness of virtual prototype. The mechanical properties of rolling movable teeth reducer is obtained by the time-domain graph of meshing force. It provides the basis for the optimization design and engineering analysis of reducer.
Instantaneous Dynamic Analysis of the New Stirring Kneader Shaft
Authors: Fan Zhi Min , Zhou Guang Ting , Liu Jian Ping
Published: March 2011

The finite element model of the stirring kneader shaft was built by PRO/E software, which was inserted into ANSYS. Next, the instantaneous dynamic analysis of the new stirring kneader shaft was carried out. The instantaneous dynamic response of stirring shaft about the exciting force of fluid was obtained, which was to optimize the structural parameters of the stirring shaft. The foundation for the next fatigue analysis was laid based on the instantaneous dynamic response; the fatigue life of stirring kneader shaft can be predicted.
Optimal Design for Roller Motion Track of Tire Building Machine
Authors: Meng Zhao Ming , Qiao Ya Bo , Ren C.
Published: March 2011

at present, the product quality that tire building machine presses tire is not ideal. The phenomenon that the tread isn’t pressed solidly often appears. Through analysis, the main reasons of this problem are those the actual rolling curve doesn’t accord with ideal curve enough, and roller pressure is unstable, pressure fluctuations are large. Therefore, ensuring the basic structure of institution is unchanged, this paper adopts optimization technique to calculate the size of planar linkage institutions and determine the best design result. It makes the moving point from the planar linkage institutions accord with tire section curve best. The article cites example of the engineering design, demonstrating the superiority of the new design method fully.
A Study on the Properties of Polypyrrole Coated Polyester Fiber
Authors: Xu Jin Yun , Jin Xin
Published: March 2011

Polyester fibers are used in a great many textile and industrial materials, their undesirable electrical advantage bring about disadvantages. Direct polymerization of pyrrole on polyester fibers may provide useful tools for producing new conducting materials. Polyester/polypyrrole composite fiber was prepared by in situ oxidative polymerization from liquid phase pyrrole at room temperature. The result showed that deposition of pyrrole is an effective way to impart conductivity to polyester fiber. The Tg of coated polyester fiber decreased and the surface of Ppy coated polyester fiber displayed an evident granular structure. In addition, the Ppy coatings have good stability under washing and heating treatment, which demonstrate that polypyrrole has good affinity to polyester fiber.
Experimental Research on Seal Ring in the Pipeline Mixed with r-EPDM
Authors: Zeng Xian Kui , Su Hui Hui , Wang Chuan Sheng
Published: March 2011

The selection of seal ring material produces an effect on the sealing performance and service life significantly. And the material properties can affect the performance of seal ring directly. The degree of influences of four factors [Ratio, silica, DCP and curing temperature] in the formula on the quality of seal ring were analyzed by using orthogonal test, R/S analysis and other mathematical methods. The experimental results indicate that the amount of reclaimed rubber added into the seal ring has significant effect on the physical and mechanical properties of the blend. Adding a certain amount of r-EPDM can keep the original excellent quality, at the same time it can reduces the pollution of waste rubber and the costs of raw materials.
The Effects of Interbedded Friction on Load Capacity of Rhombic Wire Wound Vessel
Authors: Wu Jun Fei , Gao Wei , Zhu Xiao Chen
Published: March 2011

From the parametric modeling, the APDL tool can be used in ANSYS to build the finite element model of rhombic wire wound vessel. Only a small amount of parameters have to be input in order to accomplish the whole process of program development such as constructing model, meshing, creating contact pairs, bringing restrictions and loads to bear on vessels as well as solving and post-processing. It can be easy to use the developed batch program to achieve the finite element analysis of vessels and get the influence of interbedded friction on the load capacity of rhombic wire wound vessel under different working pressures.
Determination of Thermo-Physical Properties of Rubber and its Effect on Curing Temperature Field of Tire
Authors: Li Qing Ling , Fan Lian Cui , Li Tao
Published: March 2011

The main purpose of this paper was to determine the thermo-physical properties in different parts of tire rubber and analyze the influence of the thermo-physical properties with temperature variation on the curing temperature field of tire. Thermo-physical properties in different parts of tire rubber were measured by NanoflashTM in the curing process, the relation curve of thermo-physical properties on temperature was obtained, and the linear relations of heat conductivity and specific heat of rubber on temperature were obtained by the regression analysis. Using the finite element software to build a two-dimensional model of the tires, and curing temperature field distribution was predicted by simulating the tire vulcanization process .The temperature distribution and variation curve of temperature measuring points were obtained in the cueing process. The analysis result indicates that the thermo-physical properties have a significant impact on the temperature field, and the influence of the heat conductivity on temperature field is more obvious than that of specific heat.
5m Drum’s FEA and Optimum Design Based on SolidWorks Simulation
Authors: Bu Qiu Xiang
Published: March 2011

Giant tire is characterized by low-speed high load, and conditions of use harsh. Drum is a core component of giant tire drum testing machine. Carried on the analysis to the drum's lasting quality experiment operating mode, using SolidWorks Simulation to carry on the finite element analysis (model building, grid division, boundary condition load and so on), obtained the drum's stress distributed and displacement distribution graphic solution. The quality minimum optimization design of the drum's FEA reduces the drum's design cost reasonably and shortens the design cycle effectively, has certain value engineering.
Physical Properties of Waste Lignin/HDPE Composites
Authors: Liu Tian , Wang Qing Wen , Zhao Hui
Published: March 2011

The effective utilization of lignin waste has been a main concern in the bio-ethanol industry which uses straw and stalks as feedstock. In this study the lignin waste was incorporated into high density polyethylene (HDPE) to make composites by extruded pellet fabrication and thermoform process. With the increasing of the lignin content from 55% to 75%, the static flexural strength of the resulting blends was hardly influenced, but the tensile strength decreased 42%. The mechanical and dimensional stability tests both showed that the addition of 4% MAPE promoted the interfacial bonding between lignin and HDPE. The DSC analysis showed the presence of lignin scarcely influences the thermal behavior of pure HDPE and the composites.
Study on the Applied Research of a Different-Speed Mixer
Authors: Fan Zhi Min , Li Hui Min , Zhou Guang Ting
Published: March 2011

The development situation and existing problems of mixing equipment, working principle and application of a different-speed mixer, theoretical and experimental research of a new different-speed mixer is presented in this paper, its development trend is also discussed.
Single Screw Extruder Characteristics on Friction and Heat Generated with the Barrel Carved Spiral Groove
Authors: Tong Feng Hua , Shi Da Li , Qin Jian Hua
Published: March 2011

To make single-screw extruder with extrusion pressure enough, through theory of friction-induced extrusion pressure，which has been generally accepted in the industry. The barrel designed modular structure, in the before barrel carved groove, to add the friction coefficient between barrel and solid material. It form extrusion pressure In this section by exponential increase. This papers analyze that use of spiral groove instead of linear grooves can effectively reduce the frictional heat generation.
Composite Pressure Vessel Stress Analysis and Failure Research
Authors: Luo Xiao Ling , Liu Liang Liang
Published: March 2011

The paper sums up structural characteristics and design and manufacture status quo of composite pressure vessels and puts forward coherent stress distribution calculation methods and specifies some subjective and objective factors of composite pressure vessel failure and points out that composite pressure vessel analysis is still at an initial stage. The paper has some reference values for composite pressure vessel research.
Hydrophobic Modification of Natural Cellulose Fiber with MMA via Surface-Initiated ARGET ATRP
Authors: Li Gang , Yu Hai Peng , Liu Yi Xing
Published: March 2011

To convert the hydrophilic cotton fiber into hydrophobic, grafting methyl methacrylate (MMA) on cotton fiber surface using ARGET (activators regenerated by electron transfer) ATRP (atom transfer radical polymerization) was studied in this paper. Four parallel experiments with different reaction time (2h/4h/6h/8h) were designed. The modified cotton fibers and the untreated control were examined using FTIR, SEM and contact angle analysis. The results show that as the reaction time prolonged, the peak of carbonyl stretching band of 2-bromoester at 1730cm-1 was stronger and the surface of cotton fiber was rougher, which demonstrates MMA has been grafted on the surface of cotton fiber successively and its amount increases with the reaction time. As the results of contact angle measurement, it shows that the hydrophilicity of cotton fiber can easily be modified by grafting of MMA, but the increasing amount of grafting chain had no obvious effects on further improving its hydrophobicity.
Removal of Cesium from Aqueous Solutions Using Crosslinked Amphoteric Starch Prepared by Microwave Treatment
Authors: Zou Li Xia , Liu Qing Cheng , Rong Jing Hua
Published: March 2011

Crosslinked amphoteric starches (CAS) with quaternary ammonium cationic and carboxymethyl anionic groups were prepared by a microwave heating and traditional heating method, respectively . The Structural of the two CAS particles were characterized with powder X-ray diffraction (XRD)and SEM. Sorption capacity of two CAS were investigated for cesium (Cs) in batch equilibrium studies. Kinetic studies showed that the sorption process were rapid and saturation were attained within 40 min. The two different equilibrium sorption isotherm models applied to the experimental data and the model parameters were obtained from these non linear regressions. The studies revealed that CAS prepared using microwave seems to be one of a promising biosorbents for recovery of cesium from liquid nuclear wastes.
Effect of the neridronate on RANKL release in differentiated primary human osteoblasts
Authors: Nicolin Vanessa , Valentini Roberto , Bortul Roberta , Fancellu Giovanni
Published: March 2011

Bisphosphonates are important inhibitors of bone resorp- tion and widely used clinically to treat osteoporosis, metabolic bone diseases and other orthopaedic disorders . Inhibiting osteoclasts via the mevalonate pathway is recognized as the primary mechanism of its inhibitory action. Recent evidence suggests that bisphosphonates may regulate essential signaling molecules involved in osteoclastogenesis such as RANKL (receptor activator of NF-kB ligand) which are synthesized by osteoblasts. In this report we have investigated into the neridronate-osteoblast interactions in modulating essential signaling molecule such as RANKL.
Sensitivity of mesoscale model urban boundary layer meteorology to the scale of urban representation
Authors: Flagg D. D. , Taylor P. A.
Published: March 2011

Abstract. Mesoscale modeling of the urban boundary layer requires careful parameterization of the surface due to its heterogeneous morphology. Model estimated meteorological quantities, including the surface energy budget and canopy layer variables, will respond accordingly to the scale of representation. This study examines the sensitivity of the surface energy balance, canopy layer and boundary layer meteorology to the scale of urban surface representation in a real urban area (Detroit-Windsor (USA-Canada)) during several dry, cloud-free summer periods. The model used is the Weather Research and Forecasting (WRF) model with its coupled single-layer urban canopy model. Some model verification is presented using measurements from the Border Air Quality and Meteorology Study (BAQS-Met) 2007 field campaign and additional sources. Case studies span from "neighborhood" (10 s ~308 m) to very coarse (120 s ~3.7 km) resolution. Small changes in scale can affect the classification of the surface, affecting both the local and grid-average meteorology. Results indicate high sensitivity in turbulent latent heat flux from the natural surface and sensible heat flux from the urban canopy. Small scale change is also shown to delay timing of a lake-breeze front passage and can affect the timing of local transition in static stability.
Magnetic flux transfer in the 5 April 2010 Galaxy 15 substorm: an unprecedented observation
Authors: Connors M. , Russell C. T. , Angelopoulos V.
Published: March 2011

Abstract. At approximately 08:25 UT on 5 April 2010, a CME-driven shock compressed Earth's magnetosphere and applied about 15 nT of southward IMF for nearly an hour. A substorm growth phase and localized dipolarization at 08:47 UT were followed by large dipolarizations at 09:03 UT and 09:08 UT, observed by GOES West (11) in the midnight sector, and by three THEMIS spacecraft near X=−11, Y=−2 RE. A large electric field at the THEMIS spacecraft indicates so much flux transfer to the inner magnetosphere that "overdipolarization" took place at GOES 11. This transfer is consistent with the ground and space magnetic signature of the substorm current wedge. Significant particle injections were also observed. The ensemble of extreme geophysical conditions, never previously observed, is consistent with the Near-Earth Neutral Line interpretation of substorms, and subjected the Galaxy 15 geosynchronous satellite to space weather conditions which appear to have induced a major operational anomaly.
Evaluating uncertainty estimates in hydrologic models: borrowing measures from the forecast verification community
Authors: Franz K. J. , Hogue T. S.
Published: March 2011

Abstract. The hydrologic community is generally moving towards the use of probabilistic estimates of streamflow, primarily through the implementation of Ensemble Streamflow Prediction (ESP) systems, ensemble data assimilation methods, or multi-modeling platforms. However, evaluation of probabilistic outputs has not necessarily kept pace with ensemble generation. Much of the modeling community is still performing model evaluation using standard deterministic measures, such as error, correlation, or bias, typically applied to the ensemble mean or median. Probabilistic forecast verification methods have been well developed, particularly in the atmospheric sciences yet, few have been adopted for evaluating uncertainty estimates in hydrologic model simulations. In the current paper, we overview existing probabilistic forecast verification methods and apply the methods to evaluate and compare model ensembles produced from different parameter uncertainty estimation methods. The Generalized Uncertainty Likelihood Estimator (GLUE), a modified version of GLUE, and the Shuffle Complex Evolution Metropolis (SCEM) are used to generate model ensembles for the National Weather Service SACramento Soil Moisture Accounting (SAC-SMA) model for 12 forecast basins located in the Southeastern United States. We evaluate the model ensembles using relevant metrics in the following categories: distribution, correlation, accuracy, conditional statistics, and categorical statistics. We show that the probabilistic metrics are easily adapted to model simulation ensembles and provide a robust analysis of parameter uncertainty, one that is commensurate with the dimension of the ensembles themselves. Application of these methods requires no information in addition to what is already available as part of traditional model validation methodology and considers the entire ensemble or uncertainty range in the approach.
Quantifying flow and remediation zone uncertainties for partially opened wells in heterogeneous aquifers
Authors: Ni C.-F. , Lin C.-P. , Li S.-G. , Chen J.-S.
Published: March 2011

Abstract. This study presents a numerical first-order spectral model to quantify flow and remediation zone uncertainties for partially opened wells in heterogeneous aquifers. Taking advantages of spectral theories in solving unmodeled small-scale variability in hydraulic conductivity (K), the presented nonstationary spectral method (NSM) can efficiently estimate flow uncertainties, including hydraulic heads and Darcy velocities in r- and z profile in a cylindrical coordinate system. The velocity uncertainties associated with the particle backward tracking algorithm are then used to estimate stochastic remediation zones for scenarios with partially opened well screens. In this study the flow and remediation zone uncertainties obtained by NSM were first compared with those obtained by Monte Carlo simulations (MCS). A layered aquifer with different geometric mean of K and screen locations was then illustrated with the developed NSM. To compare NSM flow and remediation zone uncertainties with those of MCS, three different small-scale K variances and correlation lengths were considered for illustration purpose. The MCS remediation zones for different degrees of heterogeneity were presented with the uncertainty clouds obtained by 200 equally likely MCS realizations. Results of simulations reveal that the first-order NSM solutions agree well with those of MCS for partially opened wells. The flow uncertainties obtained by using NSM and MCS show identically for aquifers with small ln K variances and correlation lengths. Based on the test examples, the remediation zone uncertainties are not sensitive to the changes of small-scale ln K correlation lengths. However, the increases of remediation zone uncertainties are significant with the increases of small-scale ln K variances. The largest displacement uncertainties may have several meters of differences when the ln K variances increase from 0.1 to 1.0. Such results are also valid for the estimations of remediation zones in layered aquifers.
Silicon pool dynamics and biogenic silica export in the Southern Ocean, inferred from Si-isotopes
Authors: Fripiat F. , Cavagna A.-J. , Dehairs F. , Speich S. , André L. , Cardinal D.
Published: March 2011

Abstract. Water column silicon isotopic signatures (δ30Si) of silicic acid (Si(OH)4) in the Southern Ocean were measured along a meridional transect from South Africa (Subtropical Zone) down to 57° S (northern Weddell Gyre). These data are the first reported for a summer transect across the whole Antarctic Circumpolar Current (ACC). δ30Si variations are large in the upper 1000 m, reflecting the effect of the silica pump superimposed upon meridional transfer across the ACC: the transport of Antarctic surface waters northward by a net Ekman drift and their convergence and mixing with warmer upper-ocean Si-depleted waters to the north. Using Si isotopic signatures, we determined different mixing interfaces between ACC water masses: the Antarctic Surface Water (AASW), the Antarctic Intermediate Water (AAIW), and the thermoclines in the low latitude areas. The residual silicic acid concentrations of end-members control the δ30Si alteration of the mixing products. With the exception of AASW, all mixing interfaces have a highly Si-depleted mixed layer end-member. These processes deplete the silicic acid AASW concentration across the different interfaces northward without significantly changing the AASW δ30Si. By comparing our new results with a previous study in the Australian sector we show that during the circumpolar transport of the ACC eastward, there is a slight but significant Si-isotopic lightening of the silicic acid pools from the Atlantic to the Australian sectors. This results either from the dissolution of biogenic silica in the deeper layers and/or from an isopycnal mixing with the deep water masses in the different oceanic basins: North Atlantic Deep Water in the Atlantic, and Indian Ocean deep water in the Indo-Australian sector. This eastward lightening is further transmitted to the subsurface waters, representing mixing interfaces between the surface and deeper layers. Using the Si-isotopic constraint, we estimate for the Greenwich Meridian a net biogenic silica production which should be representative of the annual export, at 4.5 ± 1.1 and 1.5 ± 0.4 mol Si m−2 for the Antarctic Zone and Polar Front Zone, respectively, in agreement with previous estimations. The summertime Si-supply into the mixed layer via vertical mixing was also assessed at 1.5 ± 0.4 and 0.1 ± 0.5 mol Si m−2, respectively.
Penile Reconstruction for a Case of Genital Lymphoedema Secondary to Proteus Syndrome
Authors: Ashouri F. , Manners J. , Rees R.
Published: March 2011

To our knowledge penile lymphoedema secondary to Proteus syndrome has not previously been reported. Hence we report a case of a 16-year-old male who was referred with features of right hemi-hypertrophy and severe lymphoedema affecting his scrotum and penis.
He had previously undergone scrotal reduction surgery at the age of 13, but had since developed worsening penile oedema. His main concern was that of
cosmetic appearance prior to sexual debut, and he also complained of erectile dysfunction. An MRI confirmed gross oedema of the penile skin, but normal underlying cavernosal structure, and no other anatomical abnormality. Under general anaesthesia, the entire diseased penile skin was excised. Two full thickness skin grafts were harvested from the axillae, and grafted onto the dorsal and ventral penile shaft respectively. A compressive dressing and urinary catheter was applied for 7 days. Follow-up at 4 months confirmed complete graft take with minimal scarring, and the patient was very satisfied with the cosmetic outcome. He had also noticed a recovery in erectile activity, and feels psychologically and physically more prepared for sexual relations.
Process synthesis and optimization of biorefinery configurations
Authors: Pham Viet , El‐Halwagi Mahmoud
Published: March 2011

Recently, there has been a growing interest in the development of cost‐effective technologies for the production of biofuels. A common approach to biofuel research is to invent or improve a biochemical or thermochemical conversion step. Subsequently, other conversion and separation steps are added to form a complete biorefinery flowsheet. Because this approach is structured around a specific conversion step, it may limit the possibilities of configuring optimal and innovative biorefineries. This article proposes a novel and systematic two‐stage approach to the synthesis and optimization of biorefinery configurations, given available feedstocks and desired products. In the synthesis stage, a systems‐based approach is developed to create a methodical way for synthesizing integrated biorefineries. This method is referred to as “forward‐backward” approach. It involves forward synthesis of biomass to possible intermediates and reverse synthesis starting with the desired products and identifying necessary species and pathways leading to them. In the optimization stage, Bellman's principle of optimality is applied to decompose the optimization problem into subproblems in which an optimal policy of available technologies is determined for every conversion step. An optimization formulation is utilized to determine the optimal configuration based on screening and connecting the optimal policies and generating the biorefinery flowsheet. A case study of alcohol‐producing pathways from lignocellulosic biomass is solved to demonstrate the merits of the proposed approach. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Dynamic risk analysis using alarm databases to improve process safety and product quality: Part II—Bayesian analysis
Authors: Pariyani Ankur , Seider Warren D. , Oktem Ulku G. , Soroush Masoud
Published: March 2011

Part II presents step (iii) of the dynamic risk analysis methodology; that is, a novel Bayesian analysis method that utilizes near‐misses from distributed control system (DCS) and emergency shutdown (ESD) system databases—to calculate the failure probabilities of safety, quality, and operability systems (SQOSs) and probabilities of occurrence of incidents. It accounts for the interdependences among the SQOSs using copulas, which occur because of the nonlinear relationships between the variables and behavior‐based factors involving human operators. Two types of copula functions, multivariate normal and Cuadras–Augé copula, are used. To perform Bayesian simulation, the random‐walk, multiple‐block, Metropolis–Hastings algorithm is used. The benefits of copulas in sharing information when data are limited, especially in the cases of rare events such as failures of override controllers, and automatic and manual ESD systems, are presented. In addition, product‐quality data complement safety data to enrich near‐miss information and to yield more reliable results. Step (iii) is applied to a fluidized‐catalytic‐cracking unit (FCCU) to show its performance. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Dynamic risk analysis using alarm databases to improve process safety and product quality: Part I—Data compaction
Authors: Pariyani Ankur , Seider Warren D. , Oktem Ulku G. , Soroush Masoud
Published: March 2011

In most industrial processes, vast amounts of data are recorded through their distributed control systems (DCSs) and emergency shutdown (ESD) systems. This two‐part article presents a dynamic risk analysis methodology that uses alarm databases to improve process safety and product quality. The methodology consists of three steps: (i) tracking of abnormal events over an extended period of time, (ii) event‐tree and set‐theoretic formulations to compact the abnormal‐event data, and (iii) Bayesian analysis to calculate the likelihood of the occurrence of incidents. Steps (i) and (ii) are presented in Part I and step (iii) in Part II. The event‐trees and set‐theoretic formulations allow compaction of massive numbers (millions) of abnormal events. For each abnormal event, associated with a process or quality variable, its path through the safety or quality systems designed to return its variable to the normal operation range is recorded. Event trees are prepared to record the successes and failures of each safety or quality system as it acts on each abnormal event. Over several months of operation, on the order of 106 paths through event trees are stored. The new set‐theoretic structure condenses the paths to a single compact data record, leading to significant improvement in the efficiency of the probabilistic calculations and permitting Bayesian analysis of large alarm databases in real time. As a case study, steps (i) and (ii) are applied to an industrial, fluidized‐catalytic‐cracker. © 2011 American Institute of Chemical Engineers AIChE J, 2012
High prevalence of polyclonal hypergamma‐globulinemia in adult males in Ghana, Africa
Authors: Buadi Francis , Hsing Ann W. , Katzmann Jerry A. , Pfeiffer Ruth M. , Waxman Adam , Yeboah Edward D. , Biritwum Richard B. , Tettey Yao , Adjei Andrew , Chu Lisa W. , DeMarzo Angelo , Netto George J. , Dispenzieri Angela , Kyle Robert A. , Rajkumar S. Vincent , Landgren Ola
Published: March 2011

Chronic antigenic stimulation is associated with hypergamma‐globulinemia. Higher rates of hypergamma‐globulinemia in tropical populations are maintained even with migration to temperate regions. We conducted a population‐based screening study to assess the prevalence and risk factors for hypergamma‐globulinemia in Ghana, Africa. 917 Ghanaian males (50–74 years) underwent in‐person interviews and health examinations. Serum from all persons was analyzed by electrophoresis performed on agarose gel; serum with a discrete/localized band was subjected to immunofixation. 54 persons with monoclonal proteins were excluded and 17 samples were insufficient for analysis. Using logistic regression and Chi‐square statistics we analyzed patterns of hypergamma‐globulinemia. Among 846 study subjects, the median γ‐globulin level was 1.86 g/dL. On the basis of a U.S. reference, 616 (73%) had hypergamma‐globulinemia (>1.6 g/dL) and 178 (21%) had γ‐globulin levels >2.17 gm/dl. On multivariate analyses, lower education status (P = 0.0013) and never smoking (P = 0.038) were associated with increased γ‐globulin levels. Self‐reported history of syphilis was associated with hypergamma‐globulinemia. We conclude that three quarters of this population‐based adult Ghanaian male sample had hypergamma‐globulinemia with γ‐globulin levels >1.6 g/dL. Future studies are needed to uncover genetic and environmental underpinnings of our finding, and to define the relationship between hypergamma‐globulinemia, monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma. Am. J. Hematol., 2011. © 2011 Wiley‐Liss, Inc.
Synthesis and application of long‐chain alkyl quaternary ammonium‐functionalized hyperbranched polyester
Authors: Du Yingying , Chen Qianlan , Shen Li , Xing Yanjun , Dai Jinjin
Published: March 2011

A novel kind of macromolecule, long‐chain alkyl quaternary ammonium functionalized hyperbranched polyester (QHPE), was synthesized by the reaction of hyperbranched polyester Boltorn H30 (H30) and 2,3‐epoxypropyl alkyl dimethyl ammonium chloride under alkaline conditions in dimethylformamide. After modification, the hydroxyl terminal group of H30 was converted into an ammonium functional group. A series of products was obtained with different lengths of an alkyl chain (C8, C12, C16, and C18) in the ammonium functional group. All of the products were characterized by Fourier transform infrared and NMR spectroscopy. The application of QHPEs as accelerators for the alkaline hydrolysis of poly(ethylene terephthalate) (PET) fabric was studied. The influences of the structure of QHPEs and hydrolysis conditions, such as alkaline concentration, hydrolysis time, and temperature, on the weight loss of PET fabrics were investigated. The results indicated that QHPE was a novel, efficient accelerator for the alkaline hydrolysis of PET fabrics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Impact of deprivation on short- and long-term outcomes after colorectal cancer surgery
Authors: Bharathan B , Welfare M , Borowski D W , Mills S J , Steen I N , Kelly S B
Published: March 2011

Background

The aim of the study was to determine the association between short- and long-term outcomes and deprivation for patients undergoing operative treatment for colorectal cancer in the Northern Region of England.

Methods

This was a retrospective analytical study based on the Northern Region Colorectal Cancer Audit Group database for the period 1998–2002. The Index of Multiple Deprivation 2004, an area-based measure, was recalibrated and used to quantify deprivation. Patients were ranked based on their postcode of residence and grouped into five categories.

Results

Of 8159 patients in total, 7352 (90·1 per cent) had surgery; 6953 (94·6 per cent) of the 7352 patients underwent tumour resection and 4935 (67·7 per cent) of 7294 had a margin-negative (R0) resection. Deprivation was not associated with age, sex, tumour site, stage or other tumour-related factors. Compared with the most affluent group, the most deprived patients had fewer elective operations (72·9 versus 76·4 per cent; P = 0·014), more adverse co-morbidity (P < 0·001) and fewer curative resections (65·5 versus 71·2 per cent; P < 0·001). In multivariable analysis, deprivation was not an independent predictor of postoperative death (odds ratio (OR) 0·72, 95 per cent confidence interval 0·48 to 1·06; P = 0·101) but it was a predictor of curative resection (OR 1·24, 1·01 to 1·52; P = 0·042), overall survival (HR 0·83, 0·73 to 0·95; P = 0·006) and relative survival (HR 0·74, 0·58 to 0·95; P = 0·023).

Conclusion

Deprivation, both independently and by influencing other surgical predictors, impacts on short- and long-term outcomes of patients with colorectal cancer.
Effect of North Bicyclo[3.1.0]hexane 2′‐Deoxy‐pseudosugars on RNA Interference: A Novel Class of siRNA Modification
Authors: Terrazas Montserrat , Ocampo Sandra M. , Perales José Carlos , Marquez Victor E. , Eritja Ramon
Published: March 2011

North bicyclo methanocarba thymidine (TN) nucleosides were substituted into siRNAs to investigate the effect of bicyclo[3.1.0]hexane 2′‐deoxy‐pseudosugars on RNA interference activity. Here we provide evidence that these modified siRNAs are compatible with the intracellular RNAi machinery. We studied the effect of the TN modification in a screen involving residue‐specific changes in an siRNA targeting Renilla luciferase and we applied the most effective pattern of modification to the knockdown of murine tumor necrosis factor (TNF‐α). We also showed that incorporation of TN units into siRNA duplexes increased their thermal stabilities, substantially enhanced serum stabilities, and decreased innate immunostimulation. Comparative RNAi studies involving the TN substitution and locked nucleic acids (LNAs) showed that the gene‐silencing activities of TN‐modified siRNAs were comparable to those obtained with the LNA modification. An advantage of the North 2′‐deoxy‐methanocarba modification is that it may be explored further in the future by changing the 2′‐position. The results from these studies suggest that this modification might be valuable for the development of siRNAs for therapeutic applications.
An exceptional combination of congenital coronary anomalies
Authors: Kharrat Ilyes , El‐Fassy Eric , Amabile Nicolas
Published: March 2011

We present a case of congenital coronary artery anomalies combining the absence of the circumflex artery, ectopic origins of left anterior descending and diagonal arteries and abnormal courses of these vessels. These rare anomalies were detected during an elective coronary angiography in a patient with stable angina that was related to significant stenosis of the posterolateral and middle right coronary artery. A computed tomography scanner with three‐dimensional reconstructions confirmed the anatomy.© 2011 Wiley Periodicals, Inc
Determination of rank by augmentation (DRAUG)
Authors: Malinowski Edmund R.
Published: March 2011

Determining the rank of a chemical matrix is the first step in many multivariate, chemometric studies. Rank is defined as the minimum number of linearly independent factors after deletion of factors that contribute to random, nonlinear, uncorrelated errors. Adding a matrix of rank 1 to a data matrix not only increases the rank by one unit but also perturbs the primary factor axes, having little effect on the secondary axes associated with the random errors in the measurements. The primary rank of a data matrix can be determined by comparing the residual variances obtained from principal component analysis (PCA) of the original data matrix to those obtained from an augmented matrix. The ratio of the residual variances between adjacent factor levels represents a Fisher ratio that can be used to distinguish the primary factors (chemical as well as instrumental factors) from the secondary factors (experimental errors). The results gleaned from model studies as well as those from experimental studies are used to illustrate the efficacy of the proposed methodology. The method is independent of the nature of the error distribution. Limitations and precautions are discussed. An algorithm, written in MATLAB format, is included. Copyright © 2011 John Wiley & Sons, Ltd.
A Facile Route to Difunctionalized Monosubstituted Octasilsesquioxanes
Authors: Liu Hongzhi , Puchberger Michael , Schubert Ulrich
Published: March 2011

A series of difunctionalized monosubstituted octasilsesquioxanes have been synthesized that bear ester, amino acid, alcohol, haloalkyl, or azido functional groups. These units are suitable nanobuilding blocks for the preparation of new organic–inorganic hybrid materials.