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Electrochemical Perforance and Synthesis of Nanostructured Lead Oxide  [cached]
Huiqi Wang
Modern Applied Science , 2010, DOI: 10.5539/mas.v4n4p116
Abstract: This paper describes a facial in situ synthesis method of nanostructured lead oxide powders. Lead oxide crystallites was reproducibly prepared by optimization of the temperature condition at 700?. The morphology, crystallization process, speci?c surface area and electrochemical performance of PbO was characteriazed by different analytical methods such as XRD, SEM, TEM, BET gas sorption speci?c surface area measurements and electrochemical tests . The XRD showed that the PbO is mixtures of α- and β- phases. TEM observations indicated exhibited similar morphologies with micrometer sized irregular block shapes. The BET surface area of PbO powders is increased up to 11 m2 g 1. For such PbO powders applied as anode materials in Lead acid batteries, we have managed to retain a reversible capacity above 60 mAh g 1 beyond cycles.
The Effect of Magnesium Sulfate on Bleeding Time and Nitric Oxide Production in Preeclamsia
Narges Moslemizade,Alireza Rafiei,Fereshteh Yazdani,Zahra Hosseini-khah
Pakistan Journal of Biological Sciences , 2011,
Abstract: Preeclampsia is a disease regarding with altered vascular reactivity leading to hypertension of the mother and metabolic alterations in the fetus. This study aimed to assess nitric oxide and bleeding time following administration of magnesium sulfate to preeclamtic patients compared to normotensive pregnant women. A total of 112 subjects (56 preeclamtic patients and 56 normotensive pregnant controls) were enrolled in this case-control study. Cases and controls were matched for age, BMI, gestational age, parity and gravidity. Total concentration of nitrite and nitrate (NOx) was measured before and during magnesium sulfate (MgSO4) treatment using a modified Griess-based method. Results: Systolic and diastolic blood pressures were significantly decreased during MgSO4 treatment in preeclamtic patients (p<0.0001). NOx levels were significantly increased in preeclamtic women after MgSO4 administration (33.7±18.5 vs. 50.2±21.6, p<0.0001) but it was not seen in normotensive parturients (52.4±28.9 vs. 57.3±21.7, p = 0.362). The bleeding time was scarcely increased following magnesium sulfate treatment in preeclamptic patients compared to normotensive pregnant women but it was not significant (p = 0.18). In addition, there was only a significantly reverse correlation between NOx levels and systolic or diastolic blood pressure in preeclamtic parturients after MgSO4 treatment (r = -0384; p = 0.003 and r = -0.29; p = 0.03, respectively). This study demonstrates that administrating MgSO4 to preeclamtic patients induced significant changes in NOx production which had a major role in modulating vasculature changes in preeclamsia.
Decomposition of trimethylamine oxide related to the use of sulfites in shrimp
CINTRA, Israel H.A.;OGAWA, Norma B.P.;SOUZA, Maria R.;DINIZ, Fábio M.;OGAWA, Masayoshi;
Ciência e Tecnologia de Alimentos , 1999, DOI: 10.1590/S0101-20611999000300003
Abstract: currently, sulfites are employed on board to inhibit melanosis (blackspot) on crustaceans. however, when used in excess this chemical compound not only can cause adverse reactions in so2-sensitive individuals, but also favors the decomposition of trimethylamine oxide (tmao) into dimethylamine (dma) and formaldehyde (fa), thus compromising the quality of the product, which can be observed mainly through the texture change of the meat after cooking. this study was conducted to verify the increase of the contents of dma and fa by the excessive use of sodium metabisulfite in white shrimp (penaeus schmitti). for laboratory trials, shrimp were beheaded, washed and immersed in a 2% sodium metabisulfite solution for 10 minutes. specimens were stored either on ice and maintained for 48 hours in refrigeration, or stored in a freezer for 48 hours. samples were collected at intervals of 0, 24 and 48 hours, and analyzed for residual so2, tmao, tma, dma and fa. the immersion of shrimp in a 2% sodium metabisulfite for 10 minutes favored the decomposition of tmao which greatly increased the contents of dma and fa. the fa and dma measured in fresh shrimp was low. moreover, the storage of shrimp tails on ice resulted in a significant reduction of the tma, dma, fa and residual so2 contents compared to the specimens under frozen storage.
Decomposition of trimethylamine oxide related to the use of sulfites in shrimp  [cached]
CINTRA Israel H.A.,OGAWA Norma B.P.,SOUZA Maria R.,DINIZ Fábio M.
Ciência e Tecnologia de Alimentos , 1999,
Abstract: Currently, sulfites are employed on board to inhibit melanosis (blackspot) on crustaceans. However, when used in excess this chemical compound not only can cause adverse reactions in SO2-sensitive individuals, but also favors the decomposition of trimethylamine oxide (TMAO) into dimethylamine (DMA) and formaldehyde (FA), thus compromising the quality of the product, which can be observed mainly through the texture change of the meat after cooking. This study was conducted to verify the increase of the contents of DMA and FA by the excessive use of sodium metabisulfite in white shrimp (Penaeus schmitti). For laboratory trials, shrimp were beheaded, washed and immersed in a 2% sodium metabisulfite solution for 10 minutes. Specimens were stored either on ice and maintained for 48 hours in refrigeration, or stored in a freezer for 48 hours. Samples were collected at intervals of 0, 24 and 48 hours, and analyzed for residual SO2, TMAO, TMA, DMA and FA. The immersion of shrimp in a 2% sodium metabisulfite for 10 minutes favored the decomposition of TMAO which greatly increased the contents of DMA and FA. The FA and DMA measured in fresh shrimp was low. Moreover, the storage of shrimp tails on ice resulted in a significant reduction of the TMA, DMA, FA and residual SO2 contents compared to the specimens under frozen storage.
Is Encephalopathy a Mechanism to Renew Sulfate in Autism?  [PDF]
Stephanie Seneff,Ann Lauritzen,Robert M. Davidson,Laurie Lentz-Marino
Entropy , 2013, DOI: 10.3390/e15010372
Abstract: This paper makes two claims: (1) autism can be characterized as a chronic low-grade encephalopathy, associated with excess exposure to nitric oxide, ammonia and glutamate in the central nervous system, which leads to hippocampal pathologies and resulting cognitive impairment, and (2), encephalitis is provoked by a systemic deficiency in sulfate, but associated seizures and fever support sulfate restoration. We argue that impaired synthesis of cholesterol sulfate in the skin and red blood cells, catalyzed by sunlight and nitric oxide synthase enzymes, creates a state of colloidal instability in the blood manifested as a low zeta potential and increased interfacial stress. Encephalitis, while life-threatening, can result in partial renewal of sulfate supply, promoting neuronal survival. Research is cited showing how taurine may not only help protect neurons from hypochlorite exposure, but also provide a source for sulfate renewal. Several environmental factors can synergistically promote the encephalopathy of autism, including the herbicide, glyphosate, aluminum, mercury, lead, nutritional deficiencies in thiamine and zinc, and yeast overgrowth due to excess dietary sugar. Given these facts, dietary and lifestyle changes, including increased sulfur ingestion, organic whole foods, increased sun exposure, and avoidance of toxins such as aluminum, mercury, and lead, may help to alleviate symptoms or, in some instances, to prevent autism altogether.
Formation and Morphology of Anodic Oxide Films of Ti

Kyo-Han Kim,XLZhu,Won-Woo Son,Yong-Soo Jeong,

材料科学技术学报 , 2001,
Abstract: The morphology and structure of the oxide films of Ti in H3PO4 were investigated by galvanos tatic anodization, SEM and XRD. The oxide film grew from some pores in the grooves to layered microdomains as increasing anodizing voltage. The crystallinity of the oxide films decreased with the increase of the concentration of the electrolyte. The model has been proposed for the growth of the oxide films by two steps, i.e. by uniform thickening and by local deposition.
Mechanically stable insoluble titanium-lead anodes for sulfate electrolytes  [PDF]
Chmiola J.,Gogotsi Y.,Ferdman A.
Science of Sintering , 2003, DOI: 10.2298/sos0302075c
Abstract: Different formulations of a new material to be used as an insoluble anode for copper electrowinning, a Ti-Pb composite, were investigated for both mechanical and electrochemical properties. Mechanical and metallographic characteristic tests, as well as short-term deposition tests were used to study the effect of the Ti/Pb ratio on anode performance. Yield strength and elastic modulus, obtained through tensile testing, significantly exceed that of lead. Metallographic procedures were used to assess the uniformity of lead distribution in the material, as well as porosity, which would be decreased below 1 % for most of the compositions under study. Short-term deposition tests were used to determine power consumption, deposit quality current efficiency and weight loss characteristics of the new anode material. The material with only 30 vol.% lead shows approximately the same electrochemical performance as a pure lead anode, but has much higher mechanical properties which prevent warping and extend the lifetime of the anode.
Surface Morphology of Annealed Lead Phthalocyanine Thin Films
P.Kalugasalam,,Dr.S.Ganesan
International Journal of Engineering Science and Technology , 2010,
Abstract: The thin films of Lead Phthalocyanine (PbPc) on glass substrates were prepared by Vacuum deposition. The thickness of the films was 450 nm. The sample annealed in high vacuum at 373 K temperature. The sample has been analysed by X-ray diffraction, scanning electron microscopy and atomic force microscopy in order to get structural and surface morphology of the PbPc thin film. The formation of XRD patterns of PbPc shows a triclinic grains (T) seen along with monoclinic (M) forms of PbPc. The sample is annealed at 373 K temperatures; the film shows peaks that assigned to the triclinic phase. SEM and AFM are the best tools to investigate the surface smoothness and to find the grain size of the particles. The grain size is calculated for all films of different thicknesses. The annealed AFM micrograph shows that the surface of the films consists of large holes. The annealed AFM image indicates a smooth surface. It is very clear that the grain size decreases with increase in the annealing temperature. The roughness also decreases with the increase in film annealing temperature. Annealed film leads to the oxidation of the hthalocyanine with oxygen absorbed or diffused. Therefore, the heat is responsible for the increase in film thickness. Since the films expand, it is believed that the porosity is increased.
Synthesis of Morphology―controlled Niobium Oxide Nanorods Array
CHAI Qing-Li, LIU Lei, PAN Hao, CHEN Jie, YU Ang, XU Mei-Gui, TU Luo, ZHOU Xing-Fu
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.01078
Abstract: Morphology―controlled niobium oxide nanorods array were successfully prepared in a mixed NH4F and H2O2 solution by using niobium powder as the starting materials via hydrothermal method. The morphology and composition of niobium oxide film were characterized by X―ray diffraction patterns(XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), respectively. The reaction time and hydrothermal temperature and concentration of NH4F, which affect the final composition and morphology of niobium oxide films, were also investigated in details. The results show that niobium oxide crystal have a strong anisotropy growth in the presence of NH4F and H2O2, which guides the oriented growth of hexagonal nanorods array on the niobium powder surface. The concentration of NH4F play great roles in the formation of the final products, the morphological of niobium oxide film is transformed from polyhedron granule to circular nanorods array and aggregated nanoparticles with the increase of NH4F concentration. Niobium oxide nanorods arrays can be obtained at Nb substrate after hythermal reaction at 150 or 10h with adding 0.5g NH4F. A formation mechanism is also proposed.
Comparative Study between Lead Oxide and Lead Nitrate Polymer as Gamma-Radiation Shielding Materials  [PDF]
A. M. Madbouly, E. R. Atta
Journal of Environmental Protection (JEP) , 2016, DOI: 10.4236/jep.2016.72023
Abstract: In this work, the Styrene-butadiene rubber (SBR)/lead oxide and the Styrene-butadiene rubber (SBR)/lead nitrate composites were prepared as gamma-radiation shielding materials. The investigated materials were prepared with three different weight percentage of lead oxide and lead nitrate (30, 50 and 70 wt%). The mass attenuation coefficients (μm) for all composite samples were measured experimentally at 511 and 661.6 keV photon energies. The measurements were made by performing transmission experiments with a 3'' × 3'' NaI (Tl) scintillation detector, which had an energy resolution of 7% at 0.662 MeV for the gamma-rays from the decay of 137Cs. The effective atomic numbers (Zeff) and the effective electron densities (Neff) were determined experimentally. Also they were determined theoretically using the obtained μm values for the studied composites samples by WinXCom program. The obtained results show that the experimental values of the composites are found to be in a good agreement with the theoretical values. It is recognized that the mass attenuation coefficient (μm), effective atomic numbers (Zeff) and the effective electron densities (Neff) are increased in the composite samples which contain lead oxides than which contain lead nitrates. Finally, the Styrene-butadiene rubber (SBR)/lead oxide is better than Styrene-butadiene rubber (SBR)/lead nitrate polymer as gamma radiation shielding.
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