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This study aims to develop a new low carbon composite material using illite clay and titanium dioxide as a stabilizing and whitening agent. It investigates the effect of the inclusion of titanium dioxide nano-powder and illite particles on optical, thermal, and mechanical performances of polypropylene (PP) matrix. The composite samples based on binary (PP-illite) and ternary (PP-illite-titania) composites at various particle contents of illite-titania have been manufactured by using a melt-compounding technique. The results showed that the low loading of titania has a significant effect on the whiteness index of the composites. The comparative analysis also demonstrated that the thermal stability was increased by approximately 7% in the case of the composites reinforced by the illite-titania at 18:2 wt%. Moreover, the addition of titania powder leads to ensure stabilization of tensile strength properties for all composites and also allowing Young’s modulus to gain increase of 83% for the composites reinforced by 2 wt% of titania powder. As for the addition of titanium dioxide until 5 wt%, an improvement in the aesthetic appearance of the composites is well noted by slightly decreasing the other specific properties. By combining the useful with the pleasant, and from different results obtained, it is proposed to use an optimal percentage of titania is less than 2% without impacting the hygroscopic and resistance of ternary composites and enhancing the rigidity of polymer products.

Metal corrosion is an important economic problem globally. One of the best ways to protect metal surfaces from corrosion is the use of corrosion inhibitors, especially non-toxic xanthenbenzoate derivatives namely: methyl 2-(6-hydroxy-3-oxo-3H-xanthen-9-yl)benzoate (MHXB) and ethyl 2-(6-hydroxy-3-oxo-3H-xanthen-9-yl)benzoate (EHXB). Toxicity of both compounds was evaluated in vivo technical. This study to assessed anticorrosion properties of both inhibitor compounds (MHXB and EHXB) on mild steel(MS) in 1 M hydrochloric acid solution by way of the potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), as well as the Energy Dispersive X-rays (EDX), scanning electron microscopy (SEM) techniques and UV–Visible. The results of the methods used indicate that increasing the concentration of the inhibitor compounds improves the effectiveness of inhibition. whereas the inhibition efficiency orders for xanthene benzoate derivatives are MHXB > EHXB with the highest inhibiting efficiency respectively of 95.0 and 90.0 percent for 10−4 M. Enhancement of inhibition performance in electrochemical techniques and increase in Rp values in impedance and mixed nature of the inhibition in polarization measurement reveals the best inhibition capacity of MHXB and EHXB over the MS. The proposed for the corrosion inhibition mechanism and the process followed the kinetic/thermodynamic model of El-Awady. Quantum chemical calculations using the Density Functional Theory (DFT) method and molecular dynamics simulations (MDS) suggest a good agreement with the experimental results.

Hydrogen effect on electronic and magnetic properties of diluted magnetic semiconductor (DMS) Cd 1− x Mn x Te for x composition of 0.125 has been investigated using the projected augmented wave (PAW) based on density functional theory (DFT) formalism within the generalized gradient approximation (GGA). The results show that the Mn dopant is spin-polarized with magnetic moment of 4.189 µ B per Mn atom at x ≈0.125. The calculated formation energies indicate that the hydrogen is not stable in CdTe and the lowest energy position for H is at the Cd–Mn bond center in Cd 0.875 Mn 0.125 Te. We find also that the existence of interstitial hydrogen decreases the magnetic moment of Cd 0.875 Mn 0.125 Te diluted magnetic semiconductor. From the calculated density of state, we observed that the presence of hydrogen does not cause a change in electronic properties of Cd 0.875 Mn 0.125 Te.

A carbon paste electrode modified with amoxicillin antibiotic was employed for the quantification of bacteria from aqueous solutions. The new electrode (AMX-CPE) revealed interesting electroanalytical detection of Staphylococcus aureus based on the adsorption of bacteria onto amoxicillin under open circuit conditions. The influence of variables such as the accumulation time, pH solution and optical density (OD) was tested by square wave voltammetry (SWV) and cyclic voltammetry (CV). The response depends on the optical density of bacteria in the bulk solution as well as the parameters involved in the preconcentration, pH and the measurement steps. The elaborate electrode was used for the detection of S. aureus in milk and showed a very good limit of detection (3.00 × 10-6) in milk.

The influence of a weak magnetic field on the electric current across silicon P+N junctions has been studied. The theoretical analysis considers two types of diodes: diodes with short base and diodes with long base and the magnetic field is assumed to be perpendicular to the direction of the electric current across the junction. The results show that the variation of the current is directly related to the variation of the hole diffusion coefficient, which is then calculated in the approximation of a P-type silicon material. The relative variation of the diffusion coefficient was found B2 dependent. Experimental investigations have then been carried out in order to validate the theoretical calculations. The experimental results were in good agreement with the theoretical development when taking into account the two types of holes in the diffusion mechanism in silicon.

The preparation of drug delivery devices using solventless fabrication procedures is of significant interest and two such procedures are described. In one such procedure, powdered polymer and micronized protein are intimately mixed and then extruded into 1 mm strands that are cut to the desired length. The polymers used were specifically designed to allow extrusion at temperatures where proteins maintain activity in the dry state. In vitro erosion and BSA release show that BSA release and polymer erosion occur concomitantly indicating an erosion-controlled process. There is a lag-time, but that can be eliminated by the addition to the mixture prior to extrusion small amounts of poly(ethylene glycol) or its methoxy derivatives. The lag-time could also be eliminated by using an AB-block copolymer where A is poly(ortho ester) and B is poly(ethylene glycol). Another means of using solventless fabrication methods is to use a semi-solid material into which drugs can be mixed at room temperature and the semi-solid injected. Data on BSA and bupivacaine release are presented.

Due to their importance in stratosphere, spectroscopic studies of halogenated carbonyls (COF2, COFCl, COCl2) and their complexes with Cl2 are reviewed, including previously unpublished data. In particular, quantitative analysis of νCO Fermi resonance has been made for free and complexed halogenated carbonyls. Ab initio calculations have been undertaken on all these structures. The structure, complexation energy and vibrational analysis at the harmonic approximations have been calculated at the self‐consistent field and Mo/ller–Plesset 2 levels. The calculated frequency shifts are in overall agreement with the experimental data. This result was not obvious owing to the weakness of the complexes.

Photolysis of argon samples containing Cl 2 , Br 2 , O 3 with 800-360 nm irradiation produced new absorptions at 940.9-932.7 and 818.9-817.5 cm −1 , which were assigned to the new BrClO and ClBrO species. Formation of these species proceeds through photodissociation of BrCl: O 3 and ClBr: O 3 complexes. Photolysis of ClBrO molecules above 400 nm produced BrCl species.

Fourier transform infrared spectroscopy has been employed to investigate the reaction of CFCl 3 (Freon 11) with atomic oxygen in argon and oxygen matrices at 12 K. Ozone was employed as a photolytic oxygen atom source. The results indicate that the only primary reaction product is COFCl when the oxygen atom is in an excited state. No intermediate was observed. Upon thermal annealing after photolysis, diffusion through the matrix leads to the efficient formation of COFCl:Cl 2 aggregates.

Ft-IR spectroscopy has been coupled with the matrix isolation technique to investigate the mechanism of the CBrCl 3 photooxidation by ozone at 12 K by UV light. COCl 2 is observed as the only primary product and CO as a secondary photolysis product. A 35 K warm up after photolysis generated phosgene complexes with Cl 2 and Br 2 . Identification of these molecular complexes was performed with mixtures of laboratory synthesized phosgene with X (X=Cl 2 , Br 2 ) trapped in argon matrices.

Fuel selection was measured in five subjects (36.0 +/- 10.5 years old; 87.3 +/- 12.5 kg; mean +/- SD) during a 120-min tethered walking with ski poles (1.12 l O(2) min(-1)) with ingestion of (13)C-glucose (1.5 g kg(-1)), before and after a 20-day 415-km ski trek [physical activity level (PAL) approximately 3], using respiratory calorimetry, urea excretion, and (13)C/(12)C in expired CO(2) and in plasma glucose. Before the ski trek, protein oxidation contributed 9.7 +/- 1.6% to the energy yield (%En) while fat and carbohydrate (CHO) oxidation provided 73.5 +/- 5.5 and 16.7 +/- 6.5%En. Plasma glucose was the main source of CHO (52.9 +/- 9.5%En) with similar contributions from exogenous glucose (27.2 +/- 3.1%En), glucose from the liver (25.6 +/- 8.3%En) and muscle glycogen (20.9 +/- 4.0%En). Endogenous CHO contributed 46.6 +/- 3.9%En. Following the ski trek %En from protein, fat, CHO, exogenous glucose and endogenous CHO were not significantly modified (10.1 +/- 1.3, 15.8 +/- 6.7, 74.1 +/- 6.5, 28.7 +/- 3.0 and 45.5 +/- 7.5%En, respectively) but the %En from plasma glucose and glucose from the liver (41.1 +/- 3.6 and 12.4 +/- 4.0%En) were reduced, while that from muscle glycogen increased (33.0 +/- 4.5%En). These results show that in subjects in the fed state with glucose ingestion during exercise, CHO is the main substrate oxidized, with major contributions from both exogenous and endogenous CHO. Following a ~3-week period of prolonged low intensity exercise, the %En from protein, fat, CHO, exogenous glucose and endogenous CHO were not modified. However, the %En from glucose released from the liver was reduced (possibly due to an increased insulin sensitivity of the liver) while that from muscle glycogen was increased.

The electrical properties of grain boundaries have been investigated by means of capacitance measurements such as deep‐level transient spectroscopy and thermally stimulated capacitance. This paper describes the evolution of the electrical properties of n‐type Σ=25 silicon bicrystals as a function of heat treatments. It results from this work, that after annealing and quenching, the Σ=25 bicrystal presents an electrical activity and that metallic impurities are responsible for the grain boundary electrostatic potential barrier. The investigations by transmission electron microscopy have shown that the grain boundary activity is in relationship with the presence of colonies of precipitates at the interface, these precipitates being silicides. The results of microanalysis experiments made elsewhere on other similar bicrystals indicate the presence of copper and nickel in the precipitates forming the colonies. The importance of the heating and cooling rates of the samples about the energy distribution of the ...

Different silicon P/sup +/N junctions prepared by the preamorphization technique have been investigated under dc magnetic field. A crystalline reference sample was equally considered. The impact of the preamorphization step on the magnetic susceptibility of the junctions is highlighted by forward and reverse current-voltage characterizations. The different measurements were performed under a dc magnetic field of intensity up to 1200 G at a sample temperature of 250 K using an Oxford Teslatron system. The relative variation of the diode current has been taken as a representative parameter of the magnetic susceptibility of the sample. The results show an increase of the magnetic susceptibility with the intensity of the magnetic field for all the samples. Nevertheless, in forward bias the magnetic susceptibility does not exceed 40% for an intensity of 1200 G and remains lower than 10% for 200 G. In reverse bias, the nitrogen preamorphized sample presents a constant susceptibility for a given intensity of magnetic field. Besides, the highest susceptibility is observed for the ambient preamorphized sample in forward bias, and for the nitrogen preamorphized sample in reverse bias. In other respects, the magnetic susceptibility has been studied as a function of the intensity of the magnetic field for a constant bias voltage in the diffusion zone of each sample. The magnetic susceptibility was proportional to B/sup 2/ in all cases. This result is in good agreement with the formulae given in literature.

Shallow P + N junctions were obtained using germanium pre-amorphization step to reduce the high diffusivity of boron implanted in silicon. The germanium implantation step was performed under different conditions of temperature: ambient temperature and nitrogen temperature. P-type doping was obtained by boron implantation at relatively low energy. To characterize and simulate the electrical behaviour of such samples, steady state current–voltage measurements have been performed at different temperatures varying between 172 and 294 K. The results show a close dependence between the current–voltage characteristics of the samples and their technological parameters of manufacturing. The pre-amorphization step at ambient temperature seems to improve the electrical behaviour of the junction. To simulate the electrical characteristics of the studied samples, a reliable model has been developed based on the classical Spice formulas and taking into account additional phenomena. The simulated curves satisfactorily fit the experimental results for all the samples.

Ge pre-amorphisation step is used to reduce the high diffusivity and the transient-enhanced diffusion of boron implanted in silicon. The aim of the process is to obtain shallow P + N junctions. The pre-amorphisation step was performed under different conditions (in ambient temperature and in nitrogen). Following the rapid thermal annealing step, end of range (EOR) defects appear at the amorphous–crystalline interface. These defects could influence the electrical characteristics of the P + N junctions. An experimental study concerning three samples has been performed without and under a magnetic field of 800 G. The magnetic susceptibility was essentially observed in the case of the reverse current. The impact of the magnetic field, studied by varying the sample temperature, permits us to show an increase of the magnetic susceptibility when the defects present in such structures are electrically active. These results are discussed in comparison with their deep-level transient spectroscopy (DLTS) spectra.

Germanium implantation into silicon substrate is currently used to preamorphisize the crystalline structure in order to avoid boron channeling effects in shallow P+N junction manufacturing. Nevertheless, after boron doping and rapid thermal annealing, different defects are formed within the structure, such as end of range defects which are created at the amorphous/crystalline interface. Our study concerns two types of shallow P+N junctions. These junctions were fabricated using low energy boron implantation at 3 KeV with a dose of 2×1015 cm-2 into high-energy germanium preamorphized n-type crystalline silicon substrates at 2.2 MeV with a dose of 1015 cm-2. In the first type, the preamorphization was performed at ambient temperature. In the second, the preamorphization was performed at liquid nitrogen temperature. Boron doping was followed by a Rapid Thermal Annealing (RTA) step for 15 s at 950 °C. Deep Level Transient Spectroscopy (DLTS) technique was used to characterize the defects formed in each structure. The impact of an ac magnetic field on the reverse current has been studied at a given bias, when sweeping the sample temperature. The measurements were performed under a low frequency (less than 1 kHz) magnetic field of a Vrms value of 2000 G, with sample temperature varying between 80 and 260 K. The results show a high activity of defects at low frequencies (1 and 10 Hz) for the nitrogen preamorphized sample. Moreover, this activity is observed at about 200 K which corresponds to the peak of the DLTS spectra of such sample. However, the ambient preamorphized sample characterized by a lower concentration of defects seems to be insensitive to the ac magnetic field. Therefore, it appears that the preamorphization-induced defects influence strongly the response of the junction to an applied ac magnetic field.

e16006 Background: Although appropriate radiotherapy and combined treatments are widely used for the patients with primary nasopharyngeal carcinoma (NPC), regional or metastatic recurrence rates are still high. This study evaluated the efficacy and toxicity of combination gemcitabine plus carboplatin (GC) chemotherapy in recurrent nasopharyngeal carcinoma (NPC). Methods: Patients with recurrent NPC who have received previous cisplatinum based chemotherapy combined with radiation therapy were eligible for this study. Patients received GC combination: gemcitabine 1,250 mg/m2; days 1, and 8; carboplatin AUC 4 on day 1. Cycles were repeated every 28 days until progression or unacceptable toxicity. Primary endpoint was response rate. Results: 25 patients were enrolled (20 males and 5 females). Median age was 46.5 years. Majority of patients (20) had metastatic disease. 63% of patients have received one previous line of treatment. There were 8 partial responses (32%), 9 stable diseases (36%), and 8 progressive ...

Electrical properties of Σ25 grain boundaries in silicon were studied by capacitance spectroscopy and electron beam induced currents (EBIC) measurements. After a high temperature annealing followed by a fast cooling, activated centers appear. Energy levels are sensitive to the heating speed. Transmission electron microscopy (TEM) reveals that electrical behavior is correlated with the formation of precipitates in colonies at the interface. They contain copper present in the crystals prior to the heat processing and they are thought to be metal silicides. They are spherical, 50–500 A in size. Their crystal lattice was determined by analysis of the extra spots after elimination of multiple scattering and corresponds to a CuSi phase not stable at room temperature.