A bispecific immunotoxin (DTAT13) targeting human IL-13 receptor (IL-13R) and urokinase-type plasminogen activator receptor (uPAR) in a mouse xenograft model

A bispecific immunotoxin (IT) called DTAT13 was synthesized in order to target simultaneously the urokinase-type plasminogen activator receptor (uPAR)-expressing tumor neovasculature and IL-13 receptor expressing glioblastoma cells with the goal of intratumoral administration for brain tumors. The recombinant hybrid was created using the non-internalizing N-terminal fragment (ATF) of uPA and the IL-13 molecule for binding plus the catalytic and translocation portion of diphtheria toxin (DT) for killing. The 71 kDa protein was highly selective for human glioblastoma in vitro showing no loss on binding compared with DTAT and DTIL13 controls. In vivo, DTAT13 caused the regression of small tumors when administered at 10 micro g/day given on a five-dose schedule every other day. DTAT13 was able to target both overexpressed uPAR and the vasculature, as demonstrated by its ability to kill HUVEC cells. Also, mortality studies indicated that DTAT13 was less toxic than DTAT or DTIL13. These findings indicate that bispecific IT may allow treatment of a broader subset of antigenically diverse patients while simultaneously reducing the exposure to toxin required than if two separate agents were employed.     

Preparations of lanthanum hexaboride (LaB6) and cerium hexaboride (CeB6)

Due to strong anti-poisoning ability, good emission stability, high emission current density, lanthanum hexaboride (LaB₆) and cerium hexaboride (CeB₆) have been maturely applied in electron emission emitter. In this paper, a new manufacturing method for LaB₆ (or CeB₆) powder was proposed by using La₂O₃ (or CeO₂), B₄C, and Al as raw materials. After high-temperature reaction in the range of 1673–1773 K and the following alkaline leaching at 90°C, LaB₆ or CeB₆ powder with particle size of about 10 μm was obtained. Furthermore, by Al metal flux method, the obtained powder was used to manufacture single crystal block with size of several millimeters.     

Laser Initiation of Tris(carbohydrazide)metal(II) Perchlorates and Bis(carbohydrazide)diperchlorato‐copper(II)

The literature‐known tris(carbohydrazide)metal(II) perchlorates [M(CHZ)₃](ClO₄)₂ (MMg²⁺ ( 1 ), Mn²⁺ ( 2 ), Co²⁺ ( 3 ), Ni²⁺ ( 4 ), and Zn²⁺ ( 5 )) and the bis(carbohydrazide)diperchloratocopper(II) ( 6 ) were prepared and characterized by elemental analysis, IR and Vis/NIR spectroscopy. The sensitivities toward mechanical, thermal, and electrical stimuli were determined for all complexes 1 – 6 . Following, confined samples of 1 – 6 were irradiated with a monopulsed laser beam at a wavelength of 940 nm. The function times between beginning irradiation and complete decomposition (“breakout” at the end of the device) were measured. Further, the influence of light‐absorbing additives was investigated to proof if the laser initiation mechanism might be photothermal or photochemical. Addition of 1 % active carbon to the samples decreased the function time and the correlated initiation threshold enormously. This was an indication that the initiation mechanism seems to be thermal.     

Effect of the Liquid-Phase Characteristic on the Microstructures and Dielectric Properties of Donor- (Niobium) and Acceptor- (Magnesium) Doped Barium Titanate

Changes in the microstructure and dielectric properties with the variation of the donor/acceptor ratio in BaTiO₃ ceramics were investigated. In donor-rich specimens, a liquid that appeared during sintering did not penetrate into grain boundaries. However, in the acceptor-rich specimens, the grains were separated by a liquid film during sintering. The much higher mobility of the liquid film than that of the grain boundaries was suggested to cause extensive grain growth in acceptor-rich BaTiO₃. The macroscopic homogenization of dopants because of grain growth in acceptor-rich specimens resulted in changes in the dielectric properties.     

锂电子电池材料LiNi1／3Co1／3Mn1／3O2的制备方法

LiNi1／3Co1／3Mn1／3O2作为一种新型的锂离子电池正极材料,其理论容量高达278mAh.g^-1,具有a—NaFeO2型层状结构,制备方法主要高温固相合成法、共沉淀法、流变相反应法、溶胶-凝胶法等,文章对制备方法进行了重点沦述,讨论了相应的电化学性能、结构特征和目前存在的问题,并对层状LiNi1／3Co1／3Mn1／3O2正极材料的发展进行了展望。     

A polymer infiltration and pyrolysis (PIP) process model for ceramic matrix composites (CMCs)

This work describes a physics-based model to simulate the polymer infiltration and pyrolysis (PIP) manufacturing process for ceramic matrix composites (CMCs). Models have been developed to characterize volumetric distribution of constituents and track porosity inside the composite at different PIP stages utilizing test data from TGA and DSC characterization of a commercial preceramic polymer. Laboratory experiments were done using C/SiC CMC specimens manufactured with a variable number of PIP cycles in order to obtain inputs for the models, and the analytical results have been shown to agree with porosity determined from physical measurements.     

Mechanism and kinetics of transesterification in poly(ethylene terephthalate) and poly(ethylene 2,6-naphthalene dicarboxylate) polymer blends

In a previous work [L. Alexandrova, A. Cabrera, M.A. Hernández, M.J. Cruz, M.J.M. Abadie, O. Manero, D. Likhatchev, Polymer 43 (2002) 5397. [1]], a model compounds study on the kinetics of a transesterification reaction in poly(ethylene terphthalate)-poly(ethylene naphthalene 2,6-dicarboxylate), PET-PEN blends, resulting from melt processing, was simulated using model compounds of ethylene dibenzoate (BEB) and ethylene dinaphthoate (NEN). A first-order kinetics was established under pseudo first-order conditions for both reactants, and thus the overall transesterification reaction was second-order reversible. Direct ester-ester exchange was deduced as a prevailing mechanism for the transesterification reaction under the conditions studied.In this work, the actual PET-PEN system was melt processed by mixing the polymers below the critical reaction temperature in a twin-screw extruder. Thereafter, the reaction was induced by temperature in open glass ampoules. A second order reversible kinetics was measured, in agreement with the kinetics established in the previous model compounds study. The equilibrium constant value corresponds to a forward rate constant which is four times larger than the reverse rate constant. The activation thermodynamic parameters confirmed the direct ester-ester exchange mechanism for the reaction.     

Microhardness and Indentation Fracture of Potassium Dihydrogen Phosphate (KDP)

Potassium dihydrogen phosphate (KDP) is an important electrooptic tetragonal crystal, often used in third harmonic generation in laser systems. We have used microindentation to measure the Vickers and Knoop hardness of KDP and the resulting cracking on (100) and (001) faces. Hardness anisotropy on the (001) face, or among the (100) and (001) faces, was small (∼20%). We observed an indentation size effect for both Vickers and Knoop hardness, for indenting loads in the range 0.24–1.96 N. The large-load Vickers hardness was estimated as 1.4 ± 0.1 GPa. We observed anisotropy in the crack sizes on (100) and (001) faces. Cracks were longer on (100) faces than on (001) faces. Assuming elastic and plastic isotropy, crack sizes were analyzed, and fracture toughness, K_c , was extracted. We present here an approximate model for analyzing crack-load microindentation data in tetragonal crystals. The model uses the minimum elastic modulus of the material. The effect of the isotropic assumption on the extracted fracture toughness is estimated at ∼33%, with a 23% contribution resulting from elastic anisotropy and 10% from the slip-system plastic anisotropy.     

Synthesis of poly(styrene-co-maleimide) and poly(octadecene-co-maleimide) nanoparticles and their utilization in paper coating

Aqueous polymer dispersions comprising of poly(styrene-co-maleimide) (SMI) or poly(octadecene-co-maleimide) (OMI) nanoparticles were synthesized by thermal imidization of the corresponding maleic anhydride copolymer precursors with ammonia using an organic solvent free process. Different reaction parameters such as temperature, time, agitation speed and stirrer geometry, and molar ratio of ammonia-to-anhydride were investigated in order to find optimal conditions. The obtained copolymer nanoparticles exhibited glass transition temperatures (T_g's) between 140 and 170 °C with particle sizes ranging from 50 to 230 nm. The compositional analysis was conducted by recording ¹H NMR and ATR-FTIR spectra. In addition, SMI dispersions were successfully spray dried and analyzed by SEM. Finally, the polymer dispersion's utility as auxiliary organic pigment in paper coating formulations was evaluated.     

Miscibility of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and poly(vinyl chloride) blends

The miscibility behaviour of biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV) blended with poly(vinyl chloride) (PVC) was investigated by using differential scanning calorimetry, dynamic mechanical thermal analysis, Fourier-transform infra-red spectroscopy and a mechanical testing system. A blend of PHB-HV containing 8% HV (PHB-8HV) with PVC was immiscible, showing two separate T_g values in all compositions: whereas a blend of PHB-HV containing 18% HV (PHB-18HV) with PVC was miscible, showing a melting-point depression and a single T_g in the whole range of compositions. For the PHB-18HV/PVC system, the C-O-C stretching vibration at 1183 cm⁻¹ of PHB-18HV and the CHCl deformation at 1254cm⁻¹ of PVC were shifted, indicating that there exists a specific intermolecular interaction between the two components. In addition, as the PVC component was increased, tensile strength and Young's modulus were increased, while the inverse behaviour was observed in elongation at break.     

The role of Rh on Pt-based catalysts: structure sensitive NO + H2 reaction on Pt(110) and Pt(100) and structure insensitive reaction on Rh/Pt(110) and Rh/Pt(100)

The catalytic activity of the Pt(110) surface for the reaction of NO + H₂ was much less than that of the Pt(100) surface. However, the catalytic activity of the Rh deposited Pt(1l0) surface was almost equal to that of the Rh deposited Pt(100) surface. That is, the catalytic reaction of NO + H₂ on Pt(110) and Pt(100) surfaces is highly structure sensitive, but it changes to structure insensitive by the deposition of Rh atoms. These results are rationalized by formation of an active overlayer on the Pt(110) and Pt(100) surfaces, which is very analogous to the Rh-O/Pt-layer formed on Rh/Pt(100), Pt/Rh(100) and Pt-Rh(100) alloy surfaces during catalysis. The formation of the common overlayer of Rh-O/Pt-layer during catalysis is responsible for the structure insensitive catalysis of Rh deposited Pt-based catalysts, which is an important role of Rh in a three way catalyst.     

CuO (Bromosphaerol) and CeMo (8 Hydroxyquinoline) microcontainers incorporated into commercial marine paints

We developed CuO and CeMo microcontainers, which were filled with Bromosphaerol (CuO (BR)), Sea-Nine 211 (CuO (SN)) and 8-Hydroxyquinoline (CeMo (8-HQ)). We created coatings on metals using the basic resins we took from the WILKENS and Re-Turn companies without additives of the companies. The coatings were studied in the laboratory after exposure to marine environment in Mikrolimano harbor in a distance of 12 km southwest from the city of Piraeus in the east coast of the Saronic Gulf (WILKENS) and Singapore harbor (Re-Turn). Laboratory measurements showed that CeMo (8-HQ) coatings exhibit better anticorrosion stability of paints in sea water than commercial paints. With regard to the incorporation of CuO (BR) into commercial paints, the results showed a drastic improvement in antifouling behavior from that resulting from commercial paints. The contact angle with water is improved by Θ = 70° to Θ = 115° possible through morphology of the surface due to the effect of the incorporation of microcontainers ensuring a better cruising behavior of the ship. This entails a dramatic rise in cruising speed, reducing fuel consumption and reducing air pollution. The technology was tested by the partial painting of two ships with our technology, one ship which traveled for a year in the Adriatic Sea (Sea Anemos) and the other traveled over a year in the Nord Sea (Berge Arzew).     

Morphology and Properties of Poly(γ-benzyl L-glutamate)-block-poly(ethylene glycol)/Poly(L-lactic acid) Blend Membrane

A series of poly(γ-benzyl L-glutamate)-block-poly(ethylene glycol) (PBLG-block-PEG)/poly(L-lactic acid) (PLLA) blend membranes were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the PBLG-block-PEG/PLLA blend membranes were investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PBLG-block-PEG/PLLA blend membranes were studied by thermogravimetric analysis (TGA), tensile tests, and contact angle testing. It was found that the introduction of PLLA could exert outstanding effects on the morphology and the properties of polypeptide copolymer membrane.     

锂离子电池正极材料LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2的研究进展

锂离子电池正极材料Li Ni1/3Co1/3Mn1/3O2具有比商业化正极材料——LiCoO2更低廉的成本、更低的毒性、更好的热稳定性,近年来受到广大科研工作者的关注。主要介绍了Li Ni1/3Co1/3Mn1/3O2正极材料的合成改性方法及其近年来在电化学性能方面所取得的成果和进展,并简要概括了该材料结构和发展趋势。不断提高Li Ni1/3Co1/3Mn1/3O2正极材料的振实密度以及电化学性能特别是其在高倍率充放电条件下的循环性能将成为相关科研工作者的研究重点。     

The interaction of sulfur with Cu/Pt(111) and Zn/Pt(111) surfaces: copper-promoted sulfidation of platinum

The interaction of sulfur with Pt(111), Zn/Pt(111) and Cu/Pt(111) has been examined using X-ray photoelectron spectroscopy (XPS), X-ray excited Auger electron spectroscopy (XAES), and thermal desorption mass spectroscopy (TDS). At temperatures between 300 and 600 K, the exposure of Pt(111) to S₂ gas produces a chemisorbed layer of sulfurwithout the formation of bulk sulfides. Exposure of S₂ to a Zn/Pt(111) alloy, at room temperature, results in a breakdown of the alloy and formation of a zinc-sulfide film on Pt(111). Further S₂ exposure at 550 K sulfidizes the remaining metallic zincwithout affecting platinum. For the Cu/Pt(111) surface alloy, on the other hand, exposure to S₂2 at 550 K leads to sulfidation of the platinum. Platinum can effectively compete for sulfur atoms bonded to copper but not for those bonded to zinc. The reaction of S₂ gas with Cu/Pt(111) surfaces produces copper sulfides that promote the sulfidation of Pt by providing surface sites for the dissociation of S₂, and by favoring the diffusion of S into the bulk of the system.     

Application of FTIR spectroscopy to determine transport properties and water-polymer interactions in polypropylene (PP)/poly(ethylene-co-vinyl alcohol) (EVOH) blend films: Effect of poly(ethylene-co-vinyl alcohol) content and water activity

This paper reports the use of FTIR spectroscopy along with gravimetric analysis to simultaneously study water sorption, transport properties and water-polymer interactions in PP/EVOH films at 25 °C, as a function of EVOH content and water vapour activity. The results indicate the existence of two different mechanisms, below (dual-mode) and above a critical concentration value close to the clustering limit activity. Several spectroscopically distinguishable “types” of sorbed water molecules with different diffusion rates have been detected, and their evolution as a function of the penetrant concentration followed. The main changes in the water structure take place from the clustering limit activity onwards. Significant differences both in the state of water and diffusion sequence of free/bound water have been found between 90/10 PP/EVOH films and blends with EVOH content ≥20%, suggesting not only composite-dependence but also morphology-dependence.     

Flammability of EVA/IFR (APP/PER/ZB system) and EVA/IFR/synergist (CaCO3, NG,and EG) composites

Poly(ethylene‐co‐vinyl acetate)/intumescent flame retardant (ammonium polyphosphate/pentaerythritol/zinc borate system) composites‐EVA/IFR (APP/PER/ZB system) and EVA/IFR/Synergist [CaCO₃, natural graphite, or expanded graphite (EG)] composites have been prepared by melting compounding method. The flammability, the combustion process, the quantity of the residual chars, the morphology of the residual chars, and the thermal stability of the chars have been investigated by cone calorimeter, scanning electron microscopy and thermo gravimetric analysis. The results indicate that heat release rate (HRR), total heat released, and total smoke release (TSR) of EVA/IFR (IFR 30 phr) composite decrease to about 67.1, 78.2, and 64% of that of pure EVA, respectively. HRR, THR, and TSR of EVA/IFR/EG (IFR 9 phr, EG 1phr) composite decrease to about 62.1, 76.2, and 44% of that of pure EVA, respectively. The quantity, the thermal stability of residual chars and the char structure are discussed to find the reasons of the phenomenon above. It has been found that the flame retardant of EVA vulcanizates is improved and the fire jeopardizing is dramatically reduced due to the addition of IFR and synergist, which can give some advice to design formulations for practical applications as cable. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Poly (ethylene oxide) (PEO) influence on mechanical,thermal, and degradation properties of PLA/PBSeT blends

Poly (lactic acid) (PLA) is an important biodegradable plastic with unique properties. However, its widespread application is hindered by its low miscibility and suboptimal degradation properties. To overcome these limitations, we investigated the mechanical, thermal, and degradation properties of PLA and poly (butylene sebacate-co-terephthalate) (PBSeT) blends in the presence of poly (ethylene oxide) (PEO). Specifically, this study aimed to identify the effects of PEO as a compatibilizer and hydrolysis accelerator in PLA/PBSeT blends. PLA (80%) and PBSeT (20%) were melt blended with various PEO contents (2–10 phr), and their mechanical, thermal, and hydrolytic properties were analyzed. All PEO-treated blends exhibited a higher elongation at break than that of the control sample, and the tensile strength was slightly reduced. In the PEO 10% sample, the elongation at break increased to 800% of that of the control sample. Differential scanning chromatography (DSC) analysis confirmed that when PEO was added to the PLA/PBSeT blends, the two glass transition temperatures (T_g) narrowed, resulting in improved miscibility of PLA and PBSeT. In addition, the hydrolytic degradation of the PLA/PBSeT/PEO blend accelerated as the PEO content increased. It was confirmed that PEO can act as a compatibilizer and hydrolysis-accelerating agent for PLA/PBSeT blends.     

Measurement of the electrochemical response time and electron paramagnetic resonance behavior of poly(o‐phenetidine)–poly(styrene sulfonic acid) and poly(2‐ethylaniline)–poly(styrene sulfonic acid) complexes

Two studies were mainly focused on the measurement of electrochemical response time and the electron paramagnetic resonance (EPR) of the substituted polyaniline (PANI) complexes poly(o‐phenetidine) (POP)–poly(styrene sulfonic acid) (PSSA) and poly(2‐ethylaniline) (P2E)–PSSA, which were prepared by the electrochemical polymerization of the monomer (o‐phenetidine or 2‐ethylaniline) with PSSA, with indium tin oxide (ITO) as a working electrode in a 1M HCl solution. Ultraviolet–visible spectra measurements showed evidence for the doped substituted PANI system to have a highly electrochemical response time recorded at a temperature of 298 K, and the results were further analyzed on the basis of the color–discolor model, which is typical of protonation systems. At the reaction time (3 s) and monomer concentration (0.6M) with PSSA (0.15 μ), the best electrochemical color/discolor time of the POP–PSSA complexes was 125/125 ms (thickness = 3.00 μm), which was faster than that of the P2E–PSSA complexes. At the same thickness (10 μm), the best electrochemical color/discolor time of the POP–PSSA complexes was 500/250 ms, which was faster than the P2E–PSSA complexes (750/500 ms). With regard to film growth rate, the POP–PSSA complexes (1.0 μm/s) were faster than the P2E–PSSA complexes (0.79 μm/s); this was attributed to the substituted PANI having a steric effect and to good reactivity by the ethoxy group (? OC₂H₅) in the molecules. The EPR spectra of the two samples were recorded both at 298 and 77 K and were further analyzed on the basis of the polaron–bipolaron model. The narrower line width of the substituted PANI complexes arose due to polarons; that is, we propose that charge transport took place through both polarons and bipolarons. Compared to their salts, this could be attributed to the lower degree of structural disorder, the oxygen absorption on the molecules, and the steric effect by the side chain group. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1211–1221, 2005     

Study of Photoluminescence Excitation Spectra of Tris(8-hydroxyquinoline)aluminum(III) (Alq3) in Solutions and Films

Absorption, photoluminescence, and photoluminescence excitation (PLE) spectra have been investigated for tris(8-hydroxyquinoline)aluminum(III) (Alq₃) in solution at various Alq₃ concentrations and in doped and neat films. The redshifted PLE spectra, with respect to the absorption spectra, are obtained, together with a dip located near the absorption band peak. The dip becomes deeper with increasing concentration. It is found that the unusual PLE spectra are caused by the penetration depth effect, not by previously suggested microcrystallites of Alq₃.