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A electrochemical cell is described comprising an anode, a cathode, a solid polymer electrolyte; and a redox shuttle additive to protect the cell against overcharging and a redox shuttle additive to protect the cell against overcharging selected from the group consisting of: (a) a substituted anisole having the general formula shown in a figure (in an uncharged state): where R{sub 1} is selected from the group consisting of H, 0CH{sub 3}, OCH{sub 2}CH{sub 3}, and OCH{sub 2}phenyl, and R{sub 2} is selected from the group consisting of OCH{sub 3}, OCH{sub 2}CH{sub 3}, OCH{sub 2} phenyl, and O{sup {minus}}Li{sup +}; and (b) a di-anisole compound having the general formula shown in a second figure (in an uncharged state): where R is selected from the group consisting of -OCH{sup 3} and -CH{sub 3}, m is either 1 or 0, n is either 1 or 0, and X is selected from the ...

Science.gov (United States)

Erosion is the main contributing factor to the decrease in lifetime of gun barrels. The precision, muzzle velocity and fire range deteriorate when the surface inside the gun tube is eroded. This study deals with gun barrel material, what happens in the ba...

Science.gov (United States)

C CCNA DPoPC @"y( mPC~ lPC; CCP0u# WSC# D kPC D`hPCs gOC0 D@dOC @Rq) bOCh DpaOC% @`0) ?u<9 D@]OC] DxZOC WOCR D@VOC D ROCG @vN% D`OOC LOC< D0KOC WPL` HOCs ...

Energy Technology Data Exchange (ETDEWEB)

Stainless steels can be nitrided at temperatures {<=}400 C to increase their hardness and wear resistance without a decreasing of their excellent corrosion resistance. Structure and properties of the surface layers produced by plasma nitriding and plasma immersion ion implantation in this temperature range were tested. There are negligible differences in the structure of the produced surface layers in spite of different interaction principles of the used technologies. However there are clear differences between the case of different steels. The case of ferritic chromium steels mainly consists of {epsilon}-nitride. Whereas the cases of austenitic and ferritic austenitic steels are characterized by expanded austenite. The corrosion resistance of the steels is reduced by nitriding only, if evident CrN-formation occurs. (orig.) 11 refs.

International Nuclear Information System (INIS)

In this work, densities #rho#, speeds of sound u, and viscosities #eta#, have been measured over the whole composition range for the binary mixtures of diethylene glycol monomethyl ether (DEGMME), CH_3(OCH_2CH_2)_2OH with 1-hexanol, CH_3(CH_2)_5OH, 1-octanol, CH_3(CH_2)_7OH, and 1-decanol, CH_3(CH_2)_9OH at T = (293.15, 298.15, 303.15, and 308.15) K along with the properties of the pure components. By using the experimental values of #rho#, u, and #eta#, excess molar volume, V_m"E, deviations in viscosity, #DELTA##eta#, isentropic compressibility #kappa#_S, deviations in isentropic compressibility #DELTA##kappa#_S, deviations of the speed of sound #DELTA#u, have been calculated. The viscosity results have also been analysed in terms of some semi-empirical equations.

International Nuclear Information System (INIS)

The synthesis of narrowly dispersed nanocrystalline TiO_2 was investigated with a surfactant aided solvothermal synthetic method in toluene solutions. When a sufficient amount of titanium isopropoxide, Ti[OCH(CH_3)_2]_4 (TIP), was added to the solution, the shapes of TiO_2 nanoparticles changed from spheres to rods. The aggregated microstructures of the nano-sized TiO_2 in systems of spheres, rods, and mixtures of spheres and rods was studied using TEM. The morphological shape of the aggregation was described in terms of the fractal dimensions. We used a box-counting method to get the fractal dimension of these systems. The fitted fractal dimensions for spheres, sphere/rod mixtures, and rods are D = 1.54, D = 1.81, and D = 1.89, respectively. The fractal dimension changed from 1.54 to 1.9 with the TIP/toluene ratio, indicating that the growth mechanism for aggregations showed different behaviors.

Energy Technology Data Exchange (ETDEWEB)

The present publication is based on facts, data, knowledge and projects, which have been incorporated in the development of an energy concept for the district Schmalkalden-Meiningen. The energy concept of a district is a concept oriented at action on and realisation of mid-term and long term decisions in the fields of energy policy, economy and ecology, which must be taken by municipal and economic decision-making bodies. The energy concept accords with the targets of the Agenda 21, the environmental targets of the Federal Republic of Germany and of the Land Thuringia. Accepting this energy concept the district Schmalkalden-Meiningen shows its willingness to contribute to a lasting development in all fields of economy and ecology and thus does justice to its increasing responsibility. (orig.) [German] Die vorliegende Veroeffentlichung baut auf Fakten, Daten, Erkenntnissen und Projekten auf, die in die Erarbeitung des Energiekonzeptes fuer den Landkreis Schmalkalden-Meiningen ...

International Nuclear Information System (INIS)

The model compounds, 8-methoxypsoralen-CH_2O(CH_2)_n-adenine (MOPCH_2OC_nAd, n=2,3,5,6,8, and 10) in which 5 position of 8-methoxypsoralen (8-MOP) is linked by various lengths of polymethylene bridge to N"9 of adenine. UV absorption spectra are identical with the sum of MOPCH_2OC3 and adenine absorption spectra. Solvent effect on the UV absorption and fluorescence emission spectra indicate that the lowest excited singlet state is the (#pi##->##pi#"*) state. The spectral characteristics of the fluorescence of MOPCH_2OC_nAd are strongly dependent upon the nature of the solvents. The fluorescence emission spectra in aprotic solvents are broad and structrueless due to the excimer formation through the folded conformation accelerated by hydrophobic #pi#-#pi# stacking interaction. Increasing polarity of the protic solvents leads to higher population of unfolded conformation stabilized through favorable solvation and H-bonding, and consequently to an increase in the ...

Energy Technology Data Exchange (ETDEWEB)

In this report statistical data are presented on a national level on emissions to air in Sweden in 1995 of sulphur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}, counted as NO{sub 2}) and carbon dioxide (CO{sub 2}). Corresponding data for 1980 and 1994 are presented as a comparison. For CO{sub 2} data for 1990 and 1994 are presented as a comparison. The total amount of SO{sub 2}-emissions to air in 1995 were 94 000 tons, which means a decrease by 3 percent since 1994. The total amount of NO{sub x}-emissions to air were 362 000 tons, a 3 percent decrease since 1993. The total amount of CO{sub 2}-emissions to air were 63 200 000 tons, an increase by 7 percent compared with 1990. Differentiated data are given for various sources of emissions, i.e. combustion of fuels, industrial processes and mobile sources. Further data are presented on emission of SO{sub 2} and NO{sub x} from combustion, separately for electricity and heat production. The total amount of SO{sub 2} and NO{sub x} ...

Energy Technology Data Exchange (ETDEWEB)

A singular stress field can occur at the edge of the joint plane in a thermally or mechanically loaded material compound. This stress field was calculated analytically and was compared with the results from the finite element method. If one of the two partners consists of ceramic material, unstable crack spread starting from faults in this strongly stressed area can lead to failure. In linear elastic material, the behaviour of a crack is clearly described by the stress intensity factors. These can be calculated for a known stress distribution in the uncracked structure by the method of the weight function. The corresponding weight functions for surface cracks parallel to the boundary surface were determined with the aid of suitable reference load cases. The effect of the position of the crack in the compound and the elastic constants of the compound are discussed. For examples, the stress intensity factors for cracks in a thermally stressed material compound were determined by the ...

Science.gov (United States)

One-electron reduction of the square-planar nickel precursor (PNP)NiCl ( 1) (PNP (-) = N[2-P(CHMe 2) 2-4-methylphenyl] 2) with KC 8 effects ligand reorganization of the pincer ligand to assemble a Ni(I) dimer, [Ni(mu 2-PNP)] 2 ( 2), containing a Ni 2N 2 core structure, as inferred by its solid-state X-ray structure. Solution magnetization measurements are consistent with a paramagnetic Ni(I) system likely undergoing a monomer dimer equilibrium. The room-temperature and 4 K solid-state X-band electron paramagnetic resonance (EPR) spectra display anisotropic signals. Low-temperature solid-state X-band EPR data at 4 K reveal rhombic values g z = 1.980(4), g x = 2. 380(4), and g y = 2.225(4), as well as a forbidden signal at g = 4.24 for the Delta M S = 2 half field transition, in accord with 2 having two weakly interacting metal centers. Utilizing an S = 1 model, full spin Hamiltonian simulation of the low-temperature EPR spectrum on the solid sample was achieved by applying a nonzero ...

Energy Technology Data Exchange (ETDEWEB)

The R and D activities of the institute focused on two major projects, ``Molecular and cellular environmental toxicology``, and ``Biophysics of multi-cellular systems``. For assessment of health risks emanating from the uptake of heavy metal compounds, work performed under the first mentioned project studies the formation of allergy-inducing metabolic products from membrane lipids, and the effects of related cellular signaling processes. These studies are accompanied by an approach to quantify and classify the toxicity of environmental organometallic compounds. Another major task is research into the pathogenesis of lung disease induced by dusts, gases, and gas-dust mixtures and the liberation of inflammatory agents by immunological cell reactions (alveolar macrophages). Atomic force microscopy is the tool used to visualize the related dynamic changes in bronchial cells. Studies for detection of the localisation and structure of the Fe-Mo co-factor in nitrogenase by means of the method ...

Energy Technology Data Exchange (ETDEWEB)

This thesis deals with the analysis of dominant loss mechanisms in direct methanol fuel cells (DMFC) and hydrogen fed polymer electrolyte membrane fuel cells (PEFC) by means of experimental characterization and modeling work. Due to different fuels used in these two fuel cell types, the dominant loss mechanisms are different in their nature. All in-situ characterization techniques that are used in this work are based on a novel test fuel cell with embedded reference electrodes. The first part of this work presents a new concept for realizing a reference electrode configuration in a polymer electrolyte membrane fuel cell by means of laser ablation. The laser beam is used to evaporate a small gap into the electrode surface of a catalyst coated membrane (CCM) to isolate the reference electrode from the working/counter electrode (WE/CE). This method enables the simultaneous ablation of the electrodes on both sides of the CCM because the membrane is transparent for the laser beam. ...