bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrating Susceptibility into Environmental Policy: An Analysis of the National Ambient Air Quality Standard for Lead
Authors: Chari Ramya , Burke Thomas A. , White Ronald H. , Fox Mary A.
Published: March 2012

Susceptibility to chemical toxins has not been adequately addressed in risk assessment methodologies. As a result, environmental policies may fail to meet their fundamental goal of protecting the public from harm. This study examines how characterization of risk may change when susceptibility is explicitly considered in policy development; in particular we examine the process used by the U.S. Environmental Protection Agency (EPA) to set a National Ambient Air Quality Standard (NAAQS) for lead. To determine a NAAQS, EPA estimated air lead-related decreases in child neurocognitive function through a combination of multiple data elements including concentration-response (CR) functions. In this article, we present alternative scenarios for determining a lead NAAQS using CR functions developed in populations more susceptible to lead toxicity due to socioeconomic disadvantage. The use of CR functions developed in susceptible groups resulted in cognitive decrements greater than original EPA estimates. EPA’s analysis suggested that a standard level of 0.15 µg/m3 would fulfill decision criteria, but by incorporating susceptibility we found that options for the standard could reasonably be extended to lower levels. The use of data developed in susceptible populations would result in the selection of a more protective NAAQS under the same decision framework applied by EPA. Results are used to frame discussion regarding why cumulative risk assessment methodologies are needed to help inform policy development.
Possible Time-Dependent Effect of Ions and Hydrophilic Surfaces on the Electrical Conductivity of Aqueous Solutions
Authors: Verdel Nada , Jerman Igor , Krasovec Rok , Bukovec Peter , Zupancic Marija
Published: March 2012

The purpose of this work was to determine the influence of mechanical and electrical treatment on the electrical conductivity of aqueous solutions. Solutions were treated mechanically by iteration of two steps: 1:100 dilution and vigorous shaking. These two processes were repeated until extremely dilute solutions were obtained. For electrical treatment the solutions were exposed to strong electrical impulses. Effects of mechanical (as well as electrical) treatment could not be demonstrated using electrical conductivity measurements. However, significantly higher conductivity than those of the freshly prepared chemically analogous solutions was found in all aged solutions except for those samples stored frozen. The results surprisingly resemble a previously observed weak gel-like behavior in water stored in closed flasks. We suggest that ions and contact with hydrophilic glass surfaces could be the determinative conditions for the occurrence of this phenomenon.
18F-labeled Pyrazolo[1,5-a]pyrimidine Derivatives: Synthesis from 2,4-Dinitrobenzamide and Tosylate Precursors and Comparative Biological Evaluation for Tumor Imaging with Positron Emission Tomography
Authors: Xu Jingli , Liu Hang , Li Guixia , He Yong , Ding Rui , Wang Xiao , Feng Man , Zhang Shuting , Chen Yurong , Li Shilei , Zhao Mingxia , Li Yingruo , Qi Chuanmin , Dang Yonghong
Published: March 2012

We previously reported 18F-labeled pyrazolo[1,5-a]pyrimidine derivatives: 7-(2-[18F]fluoroethylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carbonitrile ([18F]1) and N-(2-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7-ylamino)ethyl)-2-[18F]fluoro-4-nitro- benzamide ([18F]2). Preliminary biodistribution experiments of both compounds showed s slow clearance rate from excretory tissues which warranted further investigation for tumor imaging with PET. Here we modified [18F]1 and [18F]2 by introducing polar groups such as ester, hydroxyl and carboxyl and developed three additional 18F-18 labeled pyrazolo[1,5-a] pyrimidine derivatives: (3-Cyano-7-(2-[18F]fluoroethylamino)pyrazolo[1,5-a]-pyrimidin-5- yl)methyl acetate ([18F]3), 7-(2-[18F]fluoroethylamino)-5-(hydroxymethyl)pyrazolo[1,5-a]- pyrimidine-3-carbonitrile ([18F]4) and (S)-6-(3-cyano-5-methylpyrazolo[1,5-a]pyrimidin-7-ylamino)-2-(2-[18F]fluoro-4-nitrobenzamido)hexanoic acid ([18F]5). The radiolabeled probes were synthesized by nucleophilic substitution of the corresponding tosylate and nitro precursors with 18F-fluoride. In Vitro studies showed higher uptake of [18F]3 and [18F]4 than that of [18F]5 by S180 tumor cells. In Vivo biodistribution studies in mice bearing S180 tumors showed that the uptake of both [18F]3 and [18F]4 in tumors displayed an increasing trend while the uptake of [18F]5 in tumor decreased through the course of the 120 min study. This significant difference in tumor uptake was also found between [18F]1 and [18F]2. Thus, we compared the biological behavior of the five tracers and reported the tumor uptake kinetic differences between 2-[18F]fluoroethylamino- and 2-[18F]fluoro-4-nitro- benzamidopyrazolo[1,5-a] pyrimidine derivatives.
Protective Effect of Ischemic Postconditioning against Ischemia Reperfusion-Induced Myocardium Oxidative Injury in IR Rats
Authors: Zhang Li , Ma Jiangwei , Liu Huajin
Published: March 2012

Brief episodes of myocardial ischemia-reperfusion (IR) employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of ischemic postconditioning on an ischemic reperfusion (IR)-induced myocardium oxidative injury in rat model. Results showed that ischemic postconditioning could improve arrhythmia cordis, reduce myocardium infarction and serum creatin kinase (CK), lactate dehydrogenase (LDH) and aspartate transaminase (AST) activities in IR rats. In addition, ischemic postconditioning could still decrease myocardium malondialdehyde (MDA) level, and increased myocardium Na+-K+-ATPase, Ca2+-Mg2+-ATPase, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) activities. It can be concluded that ischemic postconditioning possesses strong protective effects against ischemia reperfusion-induced myocardium oxidative injury in IR rats.
Celiac Disease, Inflammation and Oxidative Damage: A Nutrigenetic Approach
Authors: Ferretti Gianna , Bacchetti Tiziana , Masciangelo Simona , Saturni Letizia
Published: March 2012

Celiac disease (CD), a common heritable chronic inflammatory condition of the small intestine caused by permanent intolerance to gluten/gliadin (prolamin), is characterized by a complex interplay between genetic and environmental factors. Developments in proteomics have provided an important contribution to the understanding of the biochemical and immunological aspects of the disease and the mechanisms involved in toxicity of prolamins. It has been demonstrated that some gliadin peptides resistant to complete proteolytic digestion may directly affect intestinal cell structure and functions by modulating gene expression and oxidative stress. In recent years, the creation of the two research fields Nutrigenomics and Nutrigenetics, has enabled the elucidation of some interactions between diet, nutrients and genes. Various dietary components including long chain ω-3 fatty acids, plant flavonoids, and carotenoids have been demonstrated to modulate oxidative stress, gene expression and production of inflammatory mediators. Therefore their adoption could preserve intestinal barrier integrity, play a protective role against toxicity of gliadin peptides and have a role in nutritional therapy of celiac disease.
Multiple Stimuli-Responsive Hydrogels for Metal-Based Drug Therapy
Authors: Casolaro Mario , Casolaro Ilaria
Published: March 2012

A series of homopolymeric and copolymeric hydrogels containing the N-isopropylacrylamide and vinyl monomers with α-amino acid (L-valine and L-phenylalanine) residues have been synthesized and their swelling properties were evaluated under different external stimulations. The hydrogels, obtained with different cross-linking agents (EBA and PEG-DA), have shown unique properties such as biocompatibility in addition to the stimuli-responsive characters. These ‘smart’ hydrogels exhibit single or multiple stimuli-responsiveness which could be used in biomedical applications, including controlled drug delivery. This article focuses on recent developments dealing with the delivery of metal-based drug (cisplatin, lithium) from the stimuli-responsive hydrogels proposed as platforms for cancer and bipolar disorder therapies.
A Novel Satellite Mission Concept for Upper Air Water Vapour, Aerosol and Cloud Observations Using Integrated Path Differential Absorption LiDAR Limb Sounding
Authors: Hoffmann Alex , Clifford Debbie , Aulinas Josep , Carton James G. , Deconinck Florian , Esen Berivan , Hüsing Jakob , Kern Katharina , Kox Stephan , Krejci David , Krings Thomas , Lohrey Steffen , Romano Patrick , Topham Ricardo , Weitnauer Claudia
Published: March 2012

We propose a new satellite mission to deliver high quality measurements of upper air water vapour. The concept centres around a LiDAR in limb sounding by occultation geometry, designed to operate as a very long path system for differential absorption measurements. We present a preliminary performance analysis with a system sized to send 75 mJ pulses at 25 Hz at four wavelengths close to 935 nm, to up to 5 microsatellites in a counter-rotating orbit, carrying retroreflectors characterized by a reflected beam divergence of roughly twice the emitted laser beam divergence of 15 µrad. This provides water vapour profiles with a vertical sampling of 110 m; preliminary calculations suggest that the system could detect concentrations of less than 5 ppm. A secondary payload of a fairly conventional medium resolution multispectral radiometer allows wide-swath cloud and aerosol imaging. The total weight and power of the system are estimated at 3 tons and 2,700 W respectively. This novel concept presents significant challenges, including the performance of the lasers in space, the tracking between the main spacecraft and the retroreflectors, the refractive effects of turbulence, and the design of the telescopes to achieve a high signal-to-noise ratio for the high precision measurements. The mission concept was conceived at the Alpbach Summer School 2010.
Equations for Solar Tracking
Authors: Merlaud Alexis , De Mazière Martine , Hermans Christian , Cornet Alain
Published: March 2012

Direct sunlight absorption by trace gases can be used to quantify them and investigate atmospheric chemistry. In such experiments, the main optical apparatus is often a grating or a Fourier transform spectrometer. A solar tracker based on motorized rotating mirrors is commonly used to direct the light along the spectrometer axis, correcting for the apparent rotation of the Sun. Calculating the Sun azimuth and altitude for a given time and location can be achieved with high accuracy but different sources of angular offsets appear in practice when positioning the mirrors. A feedback on the motors, using a light position sensor close to the spectrometer, is almost always needed. This paper aims to gather the main geometrical formulas necessary for the use of a widely used kind of solar tracker, based on two 45° mirrors in altazimuthal set-up with a light sensor on the spectrometer, and to illustrate them with a tracker developed by our group for atmospheric research.
Fast Direct Injection Mass-Spectrometric Characterization of Stimuli for Insect Electrophysiology by Proton Transfer Reaction-Time of Flight Mass-Spectrometry (PTR-ToF-MS)
Authors: Tasin Marco , Cappellin Luca , Biasioli Franco
Published: March 2012

Electrophysiological techniques are used in insect neuroscience to measure the response of olfactory neurons to volatile odour stimuli. Widely used systems to deliver an olfactory stimulus to a test insect include airstream guided flow through glass cartridges loaded with a given volatile compound on a sorbent support. Precise measurement of the quantity of compound reaching the sensory organ of the test organism is an urgent task in insect electrophysiology. In this study we evaluated the performances of the recent realised proton transfer reaction-time of flight mass-spectrometry (PTR-ToF-MS) as a fast and selective gas sensor. In particular, we characterised the gas emission from cartridges loaded with a set of volatile compounds belonging to different chemical classes and commonly used in electrophysiological experiments. PTR-ToF-MS allowed a fast monitoring of all investigated compounds with sufficient sensitivity and time resolution. The detection and the quantification of air contaminants and solvent or synthetic standards impurities allowed a precise quantification of the stimulus exiting the cartridge. The outcome of this study was twofold: on one hand we showed that PTR-ToF-MS allows monitoring fast processes with high sensitivity by real time detection of a broad number of compounds; on the other hand we provided a tool to solve an important issue in insect electrophysiology.
Differential Binary Encoding Method for Calibrating Image Sensors Based on IOFBs
Authors: Fernández Pedro R. , Lázaro-Galilea José Luis , Gardel Alfredo , Espinosa Felipe , Bravo Ignacio , Cano Ángel
Published: March 2012

Image transmission using incoherent optical fiber bundles (IOFBs) requires prior calibration to obtain the spatial in-out fiber correspondence necessary to reconstruct the image captured by the pseudo-sensor. This information is recorded in a Look-Up Table called the Reconstruction Table (RT), used later for reordering the fiber positions and reconstructing the original image. This paper presents a very fast method based on image-scanning using spaces encoded by a weighted binary code to obtain the in-out correspondence. The results demonstrate that this technique yields a remarkable reduction in processing time and the image reconstruction quality is very good compared to previous techniques based on spot or line scanning, for example.
Corrigendum: Survival and Treatment Patterns in Elderly Patients with Advanced Non-Small-Cell Lung Cancer in Manitoba
Authors: Ott C.L. Baunemann , Ratna N. , Prayag R. , Badiani K. , Navaratnam S.
Published: March 2012

Zoann Nugent is to be retracted from the author list[...].
A Call for Action in Survivorship Research and Care
Authors: Doll R. , Kazanjian A. , Smillie K. , Ward A. , Chasen M.
Published: March 2012

The term “cancer survivor” has been used to convey various meanings over time. [...]
Phase I Study of the Plk1 Inhibitor BI 2536 Administered Intravenously on Three Consecutive Days in Advanced Solid Tumours
Authors: Frost A. , Mross K. , Steinbild S. , Hedbom S. , Unger C. , Kaiser R. , Trommeshauser D. , Munzert G.
Published: March 2012

Background: This open-label phase i study with an accelerated titration design was performed to determine the maximum tolerated dose of BI 2536, a potent, highly selective small-molecule polo-like kinase 1 (Plk1) inhibitor. Methods: Patients with advanced solid tumours received a single 60-minute intravenous infusion of BI 2536 (50–70 mg) on days 1–3 of each 21-day treatment course. Recipients without disease progression or untenable toxicity could receive additional treatment courses. The maximum tolerated dose was determined based on dose-limiting toxicities. Other assessments included safety, pharmacokinetic profile, and antitumour activity according to the Response Evaluation Criteria in Solid Tumors. Results: The study enrolled 21 patients. The maximum tolerated dose for BI 2536 was determined to be 60 mg for the study schedule. Dose-limiting toxicities included hematologic events, hypertension, elevated liver enzymes, and fatigue. The most frequently reported drug-related adverse events were mild-to-moderate fatigue, leukopenia, constipation, nausea, mucosal inflammation, anorexia, and alopecia. The pharmacokinetics of BI 2536 were linear within the dose range tested. Plasma concentration profiles exhibited multi-compartmental pharmacokinetic behaviour, with a terminal elimination half-life of 20–30 hours. Conclusions: In the present study, BI 2536 showed an acceptable safety profile warranting further investigation of Plk1 inhibitors in this patient population.
Major Histocompatibility Complex Class I and Tumour Immuno-Evasion: How to Fool T Cells and Natural Killer Cells at One Time
Authors: Fruci D. , Benevolo M. , Cifaldi L. , Lorenzi S. , Monaco E. Lo , Tremante E. , Giacomini P.
Published: March 2012

Cytotoxic T lymphocytes (ctls) and natural killer (nk) cells lyse tumours expressing and lacking, respectively, properly conformed class i molecules of the major histocompatibility complex [mhc-i (Figure 1)] [...]
Dipole-driven self-organization of zwitterionic molecules on alkali halide surfaces
Authors: Nony Laurent , Bocquet Franck , Para Franck , Chérioux Frédéric , Duverger Eric , Palmino Frank , Luzet Vincent , Loppacher Christian
Published: March 2012

We investigated the adsorption of 4-methoxy-4′-(3-sulfonatopropyl)stilbazolium (MSPS) on different ionic (001) crystal surfaces by means of noncontact atomic force microscopy. MSPS is a zwitterionic molecule with a strong electric dipole moment. When deposited onto the substrates at room temperature, MSPS diffuses to step edges and defect sites and forms disordered assemblies of molecules. Subsequent annealing induces two different processes: First, at high coverage, the molecules assemble into a well-organized quadratic lattice, which is perfectly aligned with the <110> directions of the substrate surface (i.e., rows of equal charges) and which produces a Moiré pattern due to coincidences with the substrate lattice constant. Second, at low coverage, we observe step edges decorated with MSPS molecules that run along the <110> direction. These polar steps most probably minimize the surface energy as they counterbalance the molecular dipole by presenting oppositely charged ions on the rearranged step edge.
Enseignement du lexique et de la syntaxe
Authors: Vidalenc Jean-Louis
Published: March 2012

Cet article propose un dispositif pédagogique de niveau Bac+5 permettant aux étudiants d'acquérir les bases linguistiques les rendant aptes à gérer la documentation multimédia d'une entreprise. L'analyse lexicale et grammaticale d'un panier de petits corpus de documents collectés sur Internet représente une base solide pour maîtriser la compréhension rapide de textes.
Strategies for Enhancing and Evaluating Interactivity in Web-Based Learning and Teaching
Authors: Bodomo Adams B.
Published: March 2012

Interactivity is often discussed in constructivist approaches to education, which enable the student to evolve, understand, or construct new ideas from existing concepts. Constructivist approaches rely on active participation in the learning situation. Interaction and participation are crucial ingredients in the learning process. But interactivity, as a specific learning concept that underlies the general notions of interaction and participation, is not easily tracked and evaluated. This paper examines how to evaluate interactivity. It outlines a number of criteria and student activities to evaluate success in interactive web-based teaching. These theoretical issues are illustrated in the context of two linguistics courses that involve both web-based course delivery and face-to-face course delivery. Measures taken to achieve interactivity in these courses are discussed before proposing qualitative and quantitative criteria for evaluating interactivity. Teachers in higher education can encourage students to have a more positive attitude through effective ways of increasing interaction, such as structuring the learning environment in such a way as to achieve a ‘conversational learning community’, a learning model that promotes informal, relaxed, and interactive communities of learners and teachers.
Properties of Injectable Composite Cements and its Application in Burst Fracture of the Spine
Authors: Mao Ke Zheng , Mao Ke Ya , Cheng Zi Shen , Li Peng , Chen Zong Gang , Wang Xu Mei , Cui Fu Zhai
Published: March 2012

To explore a new type of injectable composite cements similar to the natural bone in both composition and hierarchical structure, the mineralized collagen and calcium sulphate dihydrate（CSD）were incorporated into α-calcium sulphate hemihydrate (α-CSH).The mineralized collagen was synthesized biomimetically by nanohydroxyapatite/collagen. We investigated the injectability, the setting time and the biomechanics properties to find an ideal combination of them to prepare the composite cements. SEM analysis showed biphasic cements consisting of an entanglement of calcium sulfate dihydrate and calcium-deficient hydroxyapatite crystals. We prepared porcine thoracolumbar burst fracture models and made the vertebroplasty for them by the composite cements. Imaging analysis showed the composite cements distributed uniformly and solidified well. Biomechanical test showed the ability of composite cements to repair spinal burst fractures was significant.
First Principles Study of La-Doped ZnTe on Electrical Properties
Authors: Xia Zhong Qiu , Li Rong Ping
Published: March 2012

The band structure and the intensity of states of La-doped ZnTe were obtained using the plane wave ultra soft pseudo potential method based on density functional theory (DFT) and generalized gradient approximation (GGA) according to the generally used design of the low resistance Ohmic contact in CdS/CdTe solar cells. We analyzed the electrical properties in the aspect of conductivity, which was improved by the lager electron effective mass and the high level of carrier concentration. In addition, the lattice constant of La-doped ZnTe increased, and La-doped leads to the ZnTe semiconductor degeneration.
Characterization and Immunological Evaluation of Chitosan Nanoparticles as Adjuvants for Bovine Coronavirus N Protein
Authors: Sun Qing Shen , Zhang Jia Ling , Han De Quan , Yang Yong Bo , Zhu Li , Yu Li
Published: March 2012

Chitosan nanoparticles (CNP) loaded with nucleocapsid protein of bovine coronavirus (BCV N) were prepared by ionic cross-linking method using sodium tripolyphosphate (TPP) as cross-linking agent. CNP loaded with BCV N protein was intramuscularly administered into Balb/c mice. Serum levels of anti-N protein IgG, IgM, and IgA antibodies were dynamically monitored by indirect ELISA method. Results showed that in the BCV N-loaded chitosan group, both IgA and IgG levels were found to increase significantly after the second immunization comparable to those of the Montanide ISA 206 groups. The IgM content in serum increased after the second immunization in the CNP loaded BCV N protein group. These findings indicate that CNP can be used as adjuvant in veterinary vaccine field.
Synthesis of Hole-Transporting Materials Containing Triarylamine and its Properties
Authors: Gao Wen Zheng , Li Xiang Gao , Wang Shi Rong
Published: March 2012

Two hole-transporting materials containing triphenylamine unit, 4-(4-(di-p- tolylamino)styryl)-N,N-di-p-tolylbenzenamine (TM 1) and 4-(4-(4-(di-p-tolylamino)styryl) styryl)-N,N-di-p-tolylbenzenamine(TM 2), have been designed and synthesized in this paper, which using conjugated bonds as the bridge to connect two molecules of triphenylamine. The optical spectrum, thermo-stabilization and electrochemical properties of two compounds were studied. The results show that these compounds have blue emission, proper HOMO levels and high thermal stability. Furthermore, EL devices with the configuration of ITO/HTL/Alq3/Al show the activating voltages are 11V for TM 1 and 5.5V for TM 2, respectively. The maximal luminancce efficiencies are 1.135cd/A for TM 1 and 2.068cd/A for TM 2, respectively. The difference of EL performance indicates that TM 2 possessing better hole-transporting performance than that of TM 1.
Bi-Functional Magnetical Chiral Ionic Liquids Derived from Imidazolium and Pyridinium
Authors: Qian Li Wei , Hu Xiao Ling , Guan Ping , Guo Xiao Qing
Published: March 2012

Novel Bi-Functional Magnetical Chiral Ionic Liquids (MCILs) Derived from Imidazolium and Pyridinium Were Synthesized via Simply Two Step Reactions. Optically Active Ionic Liquids Have an Asymmetric Carbon Atom Linked to the Positively Charged Imidazole Ring or Pyridine Ring, while the Magnetical Anion Contains Tetrachloroferrate (FeCl4-), their Properties of Chirality and Magnetism Were Characterized. the Structure of MCILs Would Promise a New Class of Bi-Functional Ionic Liquids.
Application of Bässler′s Energy and Position Disorder Model and Hoping Model in Hole Transport Material
Authors: Song Ya Kun , You Jing , Wang Shi Rong , Li Xiang Gao
Published: March 2012

The Bässler’s energy and position disorder model is used to study the relationship between molecular structure of hole-transport materials and performance of the photoreceptor. The result shows that dipolar moments of hole-transport materials (HTM) are inverse proportion to the half decay exposures (E1/2) of the Organic photoreceptors (OPC) which closely related with the hole-mobility of hole-transport layer. In this article Marcus hopping theory and DFT method are also used to calculate the hole-mobility of four hole-transport materials (HTM). The compare of the half decay exposures of OPCs used these material as hole-transport layer and hole mobility, dipolar moments of these molecules show that the E1/2 increases with decrease of hole mobility and dipolar moment.
A Preliminary Study on Preparation of Lithium Ion-Sieve Flat Sheet Membrane
Authors: Ji Zhi Yong , Yuan Jun Sheng , Guo Xiao Fu , Wang Jun , Li Ling
Published: March 2012

Based on preparing high purity powdered lithium ion-sieve precursor LiMn2O4, using lithium carbonate and manganese carbonate as raw materials, through roasting at high temperature of 800°C, laminar lithium ion-sieve precursor was prepared by commixing poly (vinyl chloride) (PVC) and powdered precursor in DMF (N, N-dimethylformamide) as solvent, and then powder and lithium ion-sieve flat sheet membrane was obtained through washing with HCl solution respectively. Their adsorption capacity and morphology was also characterized. The results show that both powdered lithium ion-sieve and laminar one have high adsorption capacity and selectivity for Li in solutions, and the effect of their retest is good. All these can provide a good foundation for the further study on lithium ion-sieve flat sheet membrane and lithium extraction from seawater.
Influence of Structure and Property of Plasticizers on Viscosity and Aging Process of PVC Plastisols
Authors: Xu Guo Min , Ji Yu Bi , Yang Zhao , Tan Hong
Published: March 2012

The molecular structure of DEDB,ATBC,DOTP was simulated by Chemoffice. The viscosity and aging process of PVC plastisols prepared by the three plasticizers were investigated by vibrational viscometer, and the influence of selective interactions between PVC resins and plasticizers on the viscosity and aging process of PVC plastisols were analysed. The results indicate that the viscosity and aging process of PVC plastisols are associated with the number of effective interaction groups of a plasticizer, and the more the number of effective interaction groups a plasticizer has , the higher the viscosity of the plastisols is and the more unstable the plastisols is.
Fracture Toughening of Epoxy Resins by Addition of a Novel Thermoplastic PPAEs
Authors: Xu Ya Juan , Zhou Si Kai , Jian Xi Gao
Published: March 2012

A series of blends have been prepared by adding a novel thermoplastic Poly (aryl ether) s containing phthalazinone moiety (PPAEs) in varying proportions to diglycidyl ether of bisphenol A epoxy resin (DGEBA) cured with p-diaminodiphenylsulfone (DDS). The glass transition temperature (Tg) of DGEBA /PPAEs blends were performed using differential scanning calorimetry (DSC) technique. It is proved that the addition of PPAEs resulted in enhancement of thermal properties of the blends, especially PPENK. There was moderate increase in the fracture toughness as estimated by notched impact strength. Compared to that of unmodified epoxy, the maximum toughness of the modified blends had increased 44% by addition of 15 phr PPENK. Fracture mechanisms such as plastic deformation and the ductile nature of the crack of the matrix were responsible for the increase in the fracture toughness of the blends.
The Synthesis of Polystyrene-B-Poly(4-Vinylpyridine) and its Application
Authors: Zhou Si Kai , Xu Ya Juan , Fang Shao Ming
Published: March 2012

a system of polystyrene and polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) were synthesized by using living free radical in the presence of 4-hydroxyl-2, 2, 6, 6-tetramethylpiperridine-oxyl-1(HTEMPO•) and (BPO). The polystyrene and diblock copolymers were characterized by gel permeation chromatography (GPC) and atomic force microscope (AFM). The results suggested that the polymerization of styrene in the presence of 4-hydroxyl-2, 2, 6, 6-tetramethylpiperridine-oxyl-1(HTEMPO•) and benzoyl peroxide (BPO) can be prepared with molecular weight distribution in the range of 1.15 to 1.25. The polystyrene with living groups can continuously initiate the living free radical polymerization of 4-Vinylpyridine to form the polystyrene-block-poly (4-vinylpyridine) with molecular weight distribution in the range of 1.08 to 1.35. The AFM of diblock indicated the diblock copolymer（PS-b-P4VP） is a good compatibilizer for PS and P4VP.
Adsorption of Mercury Ion on Activated Carbons from Rice Husk
Authors: SONG Xiao Lan , Zhang Ying , Yan Cheng Yin , Jiang Wen Juan , Xie Hong Jiang
Published: March 2012

The adsorption performance of mercury ion onto activated carbon prepared from rice husk with NaOH was carried out at initial concentration of 100 mg/L. The activated carbon obtained at 800 °C possessed the outstanding specific surface area of 2786 m2/g. And the results showed that the maximum adsorption capacity of Hg2+ was recorded as 342.0 mg/g due to abundant micropores of 1.076 nm. In addition, the adsorption data were well explained by the Langmuir model with the monolayer adsorption capacity of 555.6 mg/g.
Treatment of Copper-Containing Acid Mine Drainage by Neutralization-Adsorption Process Using Calcite as Neutralizer and Polyhydroxamic Acid Resin as Adsorbent
Authors: Wang Shuai , Zhao Gang , Wang Zhong Nan , Zhang Qian , Zhong Hong
Published: March 2012

Acid solution and copper-containing acid mine drainage (AMD) was treated by neutralization-adsorption process. The results showed that pH can be adjusted to 4.0 by adding 10g·L-1calcite in acid solution with pH=1.0. Adsorption and desorption performance of poly(hydroxamic acid) (PHA) resin for Cu2+and Fe3+ions were investigated by column tests. The results showed that adsorption capacities of PHA for Cu2+and Fe3+ions were satisfying, and the metals adsorbed on PHA can be eluted by sulfuric acid solution effectively. AMD of Dexing copper mine of Jiangxi was treated as a sample. The results showed that 1.5g·L-1calcite can remove almost all of the Fe3+ion, and Cu2+ion can be removed by PHA and then be eluted by sulfuric acid solution with adsorption ratio of 98.95% and elution ratio of 98.50%, separately.
Growth Mechanism, Structural and Optical Properties of ZnO Nanoparticles
Authors: Liang Xiu Juan , Hu Xiao Fang , Hu Da Wei
Published: March 2012

This paper using an electric ﬁeld-assisted direct precipitation method synthesize the ZnO nanosheets with zinc nitrate hexahydrate and sodium carbonate. The synthesis processes with and without an electric field were compared. The morphology of the ZnO nanosheets was investigated by scanning electron microscopy (SEM) measurements. The SEM results show that the application of an electric field caused the morphology transformation from flake-like to flower-like. It was found that an electric field had an effect on the crystal structure，the particle size and morphology. The photoluminescence spectrum of the synthesized ZnO nanosheets shows a strong ultraviolet emission at 249 nm. In addition，the formation mechanism of the ZnO nanosheets is discussed.
Simplified Calculation Model of Analyzing Concrete-Filled Gypsum Wall Panels
Authors: Ma Qing Zhen , Jiang Xin Liang , Zhang Bao Kui
Published: March 2012

The simplified calculating model for concrete-filled gypsum wall panels was established. The method for calculating the moment-curvature relationship of concrete core and the force-displacement skeleton curves of shear element was then proposed. The test data of concrete-filled gypsum wall panels were analyzed based on this model. The calculated curves agreed well with the experimental ones, which proves that this model has the advantages of clear mechanical conception，simple calculation and relatively good accuracy，and is convenient for calculating integral structure.
The Effect of Initial Void on the Elasto-Plastic Properties of Particle-Reinforced Composite Coating
Authors: Gu Sheng Ting , Bao Yu Mei , Chai Guo Zhong
Published: March 2012

Many defects such as micro-voids, micro-cracks are introduced during the preparation of particle reinforced composite coating, which significantly change the mechanical properties of the coating. Based on Mori-Tanaka’s concept of average stress in the matrix and Eshelby’s equivalent inclusions microscopic theory, an incremental theory coupled with ABAQUS subroutine UMAT, is developed to study the influence of initial void and void growth on elasto-plastic properties of composite coating. In the composite containing hard spherical particles, debonding of particle-matrix interface is a significant damage process, and the effect of initial void on particle damage is also considered.
Three Dimensional Surface Patterning Atop Poly(methyl Methacrylate) (PMMA)
Authors: Zhao Yong , Huang Wei Min , Purnawali Hendra
Published: March 2012

We demonstrate a novel approach to fabricate three dimensional (3-D) surface patterns atop poly(methyl methacrylate) (PMMA). This approach utilizes both shape recovery behavior and swelling phenomenon of the PMMA. The simplicity in the fabrication process affirms the low-cost nature of this approach. Moreover, as obtained 3-D patterned PMMA sample can be used as artificial compound eye.
Microstructure and Mechanical Properties Analysis of X70 Pipeline Steel with Polygonal Ferrite Plus Granular Bainite Microstructure
Authors: Zhang Zhan Zhan , Zuo Xiu Rong , Hu Yue Yue , Li Ru Tao , Zhang Zhi Ming
Published: March 2012

Microstructure and mechanical properties of X70 pipeline steel with polygonal ferrite plus granular bainite were characterized using tensile tests, Charpy V-notch impact tests, drop weight tear tests, hardness tests and scanning electron microscopy. The results of experiment indicated that X70 pipeline steel with polygonal ferrite plus granular bainite showed an excellent combination of high strength and toughness. The base metal with polygonal ferrite plus granular bainite microstructure exhibited perfect mechanical properties in terms of the transverse yield ratio of 0.81, elongation of 46%, an impact energy of 335 J at -10 °C and a shear area of 90% at 0 °C in the drop weight tear test. The heat affected zone contained coarse grain zone and fine grain zone, which exhibited good low temperature toughness of 216 J at -10 °C. The weld metal primarily consisted of intragranularly nucleated acicular ferrites which led to the high strength and toughness.
Numerical Investigation on the Process of Multi-Point Holder Forming for Titanium Mesh Sheet
Authors: Liu Zhi Wei , Li Ming Zhe , Han Qi Gang , Sui Zhou , Peng He Li
Published: March 2012

Multi-point holder forming (MPHF) adopts series of coupled holder punches, arranged between forming punches, to clamp the whole sheet in the forming zone. The multi-point holder forming processes of spherical parts of titanium mesh plate were simulated by finite element code, and the results were compared with those of multi-point die forming (MPDF). The influence of holder punch load on the deformation of spherical part in multi-point holder forming was investigated. The shape error analysis of titanium mesh formed by MPHF was performed in finial. The results showed that the spherical part had more excellent performance in multi-point holder forming, and the more deformation the titanium mesh was, the larger force of holder punch would be needed. In addition, there was a small shape error for titanium mesh part formed by MPHF before springback.
Optimization of Combined Microwave-Ultrasonic Wave Extraction of Cochineal Dye by Response Surface Methodology
Authors: Guo Yuan Heng , Zheng Hua , Zhang Hong , Ma Li Yi , Han Juan , Li Kun
Published: March 2012

For more efficient and economical extraction of cochineal dye, combined microwave-ultrasonic wave extraction was applied. It was approached 4 factors as microwave power, treated time, materials-to-liquid ratio and ultrasonic wave power. Results showed that the optimal condition individually for cochineal dye extraction was at 400W microwave power, 17min treated time, 1:8 materials-to-liquid ratio and 600W ultrasonic wave power. On the basis of single factor test, RSM optimization of the extraction was achieved at 464W microwave power, 18.48min treated time, 1:8.23 materials-to-liquid ratio and 627W ultrasonic wave power. The verification was very approximate to the predicted value from the modelling regression equation. And the best extraction grade was tesified as 4 times.
Expression, Purification and Characterization of Amantadine Receptor in Escherichia coli
Authors: Sun Hai Xin , Cao Li Min , Lin Hong , Lv Fang
Published: March 2012

In order to obtain large quantities of broadly selective receptor as one diagnose agent to detect amantadine residue, the M2 protein gene with a His-tag was ligated into pET11a and transferred into E. coli BL21 (DE3) cell. The recombinant E. coli was cultured in liquid LB culture. SDS-PAGE result showed the recombinant M2 protein (rM2) was expressed as insoluble inclusion bodies with about 18KDa in molecular size. rM2 protein was further recognized by Western blot and purified by Ni Sepharose 6 Fast Flow and then refolded. The equilibrium dialysis result showed the rM2 protein had the binding constant of 1.1×105, and stoichiometry of 4.2. The above result showed the rM2 has the potential as biological diagnose agent to the detection of amantadine residue.
Kinematic Synthesis of a Step Mechanism Based on a Five Bar Linkage
Authors: Corves Burkhard , Lonij Guido , Hüsing Mathias
Published: March 2012

On the basis of a five bar linkage it is possible to generate actinomorphic coupler curves if certain conditions, related to the kinematic dimensions and the gear ratio between the two cranks, are fulfilled. These symmetric coupler curves can then be used to realize a step mechanism by adding two additional links, taking advantage of the typical curvature characteristics of the generated coupler curve The following article starts with a short literature survey about five bar linkages in general and their use as dwell or step mechanisms in particular. Then it will be shown how the curvature properties of the coupler curves generated by five bar linkages can be determined by graphical means. It will be shown how this procedure can be advantageously applied with the help of an interactive geometry program, using the geometric determination of the curvature properties, such that an optimal step mechanism can be derived.
CAD Based Geometric Procedures for Workspace and Singularity Determination of the 3-RPR Parallel Manipulator
Authors: Arrouk Khaled Assad , Bouzgarrou Belhassen Chedli , Gogu Grigore
Published: March 2012

This paper presents a set of techniques based on the use of CAD geometric approaches for singularity surfaces and total operational workspace and joint space determination. The main emphasis is given to the use of CAD tools used to characterize and analyze the performance of planar parallel robot manipulators. The CAD environment provides powerful tools for the graphical programming and geometric feature handling. This paper points out the effectiveness of such a method in the robot design process. These developments are illustrated by the 3-RPR planar parallel manipulator case study. All of the proposed geometric algorithms are implemented in the CATIA CAD environment.
Review and Recent Results on Stewart Gough Platforms with Self-Motions
Authors: Nawratil Georg
Published: March 2012

In this paper we give a detailed review on Stewart Gough (SG) platforms with self-motions and the related Borel Bricard problem. Moreover, we report about recent results achieved by the author on this topic (SG platforms with type II DM self-motions). In context of these results, we also present two new theorems, which open the way for addressed future work. Finally, we give some remarks on planar SG platforms with type I DM self-motions and formulate a central conjecture.
Evaluation of Spring Implementation to Reduce the Required Motor Energy in a Walking Assist Exoskeleton with Linear Actuation (Walking Assist Machine Using Crutches)
Authors: Lafeber A.F. , van Dijk W. , Takeda Y.
Published: March 2012

Powered robotic exoskeletons used to assist in human locomotion require a lot of energy. The Walking Assist Machine using Crutches (WAMC) is such an exoskeleton used to assist paraplegic people in walking. It uses telescopic links actuated by DC motors and people wearing the device move crutches themselves. An simulation of the WAMC was done to see if the implementation of springs could lead to a reduction in required motor energy. The simulation showed that a configuration with springs reduces the required motor energy and increases the walking speed compared to the original configuration without springs. In the simulation the user had to spend more effort to swing the crutches forward, if the springs were implemented in the system.
Development of a Closed-Fitting-Type Walking Assistance Device for Rehabilitation
Authors: Ikehara Tadaaki , Tanaka Eiichirou , Nagamura Kazuteru , Kojima Sho , Kajihara Yousuke , Imade Nobuhiko , Yuge Louis
Published: March 2012

A Closed-Fitting-Type walking assistance device was developed. The combination of a flexible shaft with a worm gear was successfully adopted on this device to simplify its appearance and reduce its size. A hybrid control system on this device controls both torque and angle at the ankle and knee joints. As a result of walking that mounted a Walking Assistance Device to motor paralysis patient, the effect of support and the improvement of postural were achieved.
Development of a Walking-Assistance Apparatus for Neuro-Rehabilitation
Authors: Tanaka Eiichirou , Ikehara Tadaaki , Sakurai Tomohiro , Suzuki Takahiro , Roppongi Shota , Saegusa Shozo , Yuge Louis
Published: March 2012

We have developed a prototype for a walking-assistance apparatus that serves as a next-generation vehicle or a movable neuro-rehabilitation training appliance for the elderly or motor palsy patients. Our prototype uses a novel spatial parallel link mechanism with a weight-bearing lift. Flat steps of the apparatus move in parallel with the ground; the apparatus supports the entire leg alignment (including soles of the feet) and assists walking behavior at the ankle, knee, and hip joints simultaneously. To estimate the walking phase of each leg of the equipped person, pressure sensors were attached under the thenar eminence and the heel of the sole and the pressure variation at each sensing point was measured. To determine the direction in which the equipped person is walking, a pressure sensor was attached to the flexible crural link. Motor palsy patients and those with muscle weakness can walk with the assistance of the apparatus. Patients who have ambulation difficulty can also use the apparatus with a weight-bearing lift that we developed. Using the apparatus with the weight-bearing lift prevents stumbling and enables input of walking movement to the brain motor area. The validity of the weight-bearing lift can be confirmed from the results of the measured %maximum voluntary contraction (MVC).
Design Considerations Regarding a New Knee Orthosis
Authors: Copilusi Petre Cristian , Marin Mihnea , Rusu Ligia , Geonea Ionut
Published: March 2012

Orthoses are common devices to correct or prevent gait abnormalities in children. In this paper we present a new design for knee orthoses with a modular structure used for childrens locomotion recovery through kinetotherapeutic procedures, after some bone fractures or surgical interventions at the lower limb level. This research consists of an experimental analysis on children walking, a complete human lower limb dynamic analysis, modeling and simulation of a new knee orthosis. A new modular knee orthosis validated by analytical results and computer simulation using MSC Adams software was developed and is presented here.
Vision-Controlled Robot Using Hand Pose Estimation without Marker Loading Requirement
Authors: Hoshino Kiyoshi
Published: March 2012

The author proposes a visual-servoing and vision-controlled robot. It claims no sensors installed or special control means used, instead of that a high-precision and high-speed 3D hand pose estimation permits real time operation with two cameras installed at positions of loosely orthogonal relationship, using one PC of the normal specifications. Two cameras have their own database. Once sequential hand images are recorded with these two high-speed cameras, the system first selects one database with bigger size of hand region in each recorded image. Second, a coarse screening is carried out according to the proportional information on the hand image which roughly correspond to wrist rotation, or thumb or finger extension. Third, a detailed search is performed for similarity among the selected candidates. The estimated results are transmitted to a robot so that the same motions of an operator is reconstructed in the robot without time delay.
Vision on Intelligent Management of Industrial Robotics Systems
Authors: Chioreanu Adrian , Brad Stelian , Ioanes Cosmin
Published: March 2012

Based on Future Internet and ITIL, cutting edge concepts and approaches related to software service systems in distributed architectures for managing information and processes in industrial robot platforms are introduced. A new approach in defining the business relation for entities that have various interests related to industrial robots, as well as tools that support the new business approach are also identified in this paper. Further the architecture of a prototype platform designed around those concepts is presented.
Proposal for Industrial Robots Selection Criteria
Authors: Mateas Marius , Ianosi Endre
Published: March 2012

In this paper the authors propose some principles for the industrial robots performance evaluation. Also authors are searching similitudes between different industrial robots manufacturers in order to identify similitudes and underline the repeatability of certain performance indicators The indicators, which the authors are introducing, describe the performance parameters such as geometrical, kinematical and dynamical parameters. Also the paper searches for a non-dimensional solution preventing the measurement units based errors of evaluation. The quality scale is the classical one with one to ten notes.
Simulation of a Stäubli TX90 Robot during Milling Using SimMechanics
Authors: Hage Hiba , Bidaud Philippe , Jardin Nicolas
Published: March 2012

This paper proposes a simulation of a Stäubli TX90 robot based on SimMechanics Toolbox of Matlab. The goal is to predict the position and trajectory of its end-effector, with high reliability. The simulator takes into consideration loading, deformations, calibrated kinematic parameters, and all eventual sources of disturbance. An application to milling and a comparison between real and simulated data reveal the reliability and the accuracy of the simulator.