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This paper presents the design, implementation, and field measurements of a prototype marine-current power generation system (MCPGS) for capturing energy from marine current. The studied prototype MCPGS employs the flowing marine-current energy near the Cross-Sea Bridge, Peng-Hu Island, Taiwan. The design of the prototype MCPGS has to meet the practical marine-current flowing conditions and the severe environmental conditions in the ocean of Peng-Hu Island. The designed MCPGS unit consists of a three-blade marine-current turbine, a gearbox, a three-phase permanent-magnet generator, and a power converter that is used for converting generated energy to be stored in the battery. Field measured results for the studied MCPGS under different practical marine-current speeds in Peng-Hu Island are performed and analyzed. [ABSTRACT FROM AUTHOR]

The vigorous, exothermic decomposition of methyl ethylketone peroxide(MEKPO) can be stimulated by acids, metals, or heat, and the initialstage is critical to runaway reactions. Real-time thermal data areimportant in the evaluation of the hazards of fast reactions duringthe initial stage. We report the first real-time observation of thereaction of MEKPO with inorganic acids using a thermal imaging camera(TIC), which we used to determine the rate of heat evolution and torecognize the degree of the hazard present during accidents. In addition,ab initio computational methods were used to estimate the thermokineticparameters for the proposed reaction mechanisms. The results indicatedthat the temperature of the solution, the concentration of the acid,and the dehydration ability were the primary factors that affectedthe thermal reaction. This work provides a new method to study thermalchemistry and to evaluate thermal hazards. [ABSTRACT FROM AUTHOR]

Abstract: 1,1-Di(t-butylperoxy)-3,3,5-trimethylcyclohexane (TMCH) 88 mass% and 1,1-di(tertial butyl peroxy)cyclohexane (CH) 70 mass% are widely used in the polymer industry. Both are peroxyketal peroxides. Mixing peroxides with incompatible materials could induce runaway reactions in an upset situation. This is study of how acetone affects the peroxide decomposition reaction. We used differential scanning calorimetry (DSC) to detect the decomposition reaction with various ratio of acetone mixed with both peroxides. Our results showed that the acetone change from low concentration to higher concentration had a diverse effect on the peroxide decomposition reactions. A lower concentration of the acetone indicated an accelerated effect for the mixture conditions. The decomposition rates of peroxides decreased gradually as the concentration of acetone increased. [Copyright &y& Elsevier]

Abstract: Runaway reactions by methyl ethyl ketone peroxide (MEKPO) are an important issue in Asia, due to its unstable structure and extensive heat release during upset situations. This study employed differential scanning calorimetry (DSC) to draw the experimental data for MEKPO 31mass% and with acetone 99mass% on three types of heating rate of 2, 4, and 10°C/min; the kinetic and safety parameters were then evaluated via curve fitting. Through the reproducible tests in each condition, the results show that acetone is not a contaminant, because it could increase the activation energy (E a) and onset temperature (T o) when combined with MEKPO, which differs from the hazard information of the material safety data sheet (MSDS). [Copyright &y& Elsevier]

Conformationally constrained 1,2-, 1,3-, and 1,4-benzene-di-N-octylcarbamates are potent reversible competitive inhibitors of Naja mocambique mocambique phospholipase A2 with the Ki values of 11, 4, and 15 μM, respectively. With the angle of 120o between two C(benzene)–O bonds, 1,3-benzene-di-N-octylcarbamate mimics the preferable eclipsed C(sn-2)–O/C(sn-3)–O conformer of phospholipid in the enzyme-phospholipid complex. Further, a three-step phospholipase A2 inhibition mechanism by the inhibitor is proposed. [Copyright &y& Elsevier]

Tungsten oxide and titanium-oxide-doped tungsten oxide nanowires were synthesized by using the DC magnetron sputtering and infrared furnace annealing processes. Scanning election microscopy (SEM) and transmission electron microscopy (TEM) were utilized to evaluate the topography and sizes. X-ray diffraction (XRD), grazing incidence X-ray diffraction (GI-XRD), and high-resolution transmission electron microscopy (HRTEM) were used to analyze the composition and structure. From the results of HRTEM, it was discovered that the prepared nanowires have a monoclinic single-crystal phase of W 18 O 49 with lattice growth along the (010) lattice plane, and the lattice spacing is 0.378 nm, which agrees with XRD and GI-XRD results. The prepared tungsten oxide and titanium-oxide-doped tungsten oxide nanowires have turn-on voltage of 3.06 V/μm and 1.46 V/μm respectively. They also possess superior field enhancement factors of 5103 and 10667 respectively. Their behavior thus follows the Fowler-Nordheim expression for tunneling. [ABSTRACT FROM AUTHOR]

Abstract: Photodynamic therapy (PDT) is an innovative method for cancer treatment that involves the administration of a photosensitizing agent followed by exposure to visible light. An appreciable amount of a particular light source is a key to activate photosensitizers in PDT. However, the external excitation light source is a problem for clinical application because of the limitation of tissue-penetrating properties. Additionally, the wavelength of laser emission should match the absorption wavelength of each photosensitizer for efficient generation of reactive oxygen species and cell killing. In this study, Renilla luciferase-immobilized quantum dots-655 (QD-RLuc8) was used for bioluminescence resonance energy transfer (BRET)-mediated PDT to resolve these problems. The bioluminescent QD-RLuc8 conjugate exhibits self-illumination at 655 nm after coelenterazine addition, which can activate the photosensitizer, Foscan®-loaded micelles for PDT. Our results show that BRET-mediated PDT by QD-RLuc8 plus coelenterazine (20 μg/mL) successfully generated reactive oxygen species (40.8%), killed ∼ 50% A549 cells at 2 μg/mL equivalent Foscan® in vitro and significantly delayed tumor growth in vivo due to cell apoptosis under TUNEL analysis without obvious weight loss. Based on immunohistochemical observations, the proliferating cell nuclear antigen (PCNA)-negative area of tumor sections after BRET-mediated PDT was obviously increased compared to the PDT-untreated groups without an external light source. We conclude that this nanotechnology-based PDT possesses several clinical benefits, such as overcoming light penetration issues and treating deeper lesions that are intractable by PDT alone. [Copyright &y& Elsevier]

Abstract: 1,2-Ethylene-di-N-n-propylcarbamate (1) is characterized as an essential activator of Pseudomonas species lipase while 1,2-ethylene-di-N-n-butyl-, t-butyl-, n-heptyl-, and n-octyl-carbamates (2–5) are characterized as the pseudo substrate inhibitors of the enzyme in the presence of the detergent taurocholate or triton X-100. The inhibition and activation reactions are more sensitive in taurocholate than in triton X-100. From CD studies, the enzyme changes conformations in the presence of the detergent and further alters conformations by addition of the carbamate activator or inhibitor into the enzyme–detergent adduct. Therefore, this study suggests that the conformational change of lipase during interfacial activation is a continuous process to expose the active site of the enzyme to substrate. From 600MHz 1H NMR studies, the conformations of the α- and β-methylene moieties of the activator 1,2-ethylene-di-N-n-propylcarbamate in the presence of substrate change after adding taurocholate into the mixture, and the conformations of the β-methylene moieties of the inhibitor 1,2-ethylene-di-N-n-butylcarbamate in the presence of substrate alter after adding taurocholate into the mixture. [Copyright &y& Elsevier]