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Fe-substituted LiCoPO4 exhibits greatly improved cycle life relative to LiCoPO4. Whereas, pure LiCoPO4 loses more than half of its discharge capacity at the 10th cycle, the Fe-substituted LiCoPO4 retains about 100% of its discharge capacity at the 10th cycle and about 80% of its capacity at the 500th cycle. It is suggested that improved cycle life results from Fe3+ substitution on the Li and Co sites. The partial substitution of Li+ by Fe3+ and Co2+ by Fe2+ and Fe3+ was evidenced from Rietveld analysis of X-ray powder diffraction data, infrared spectroscopy, X-ray photoelectron spectroscopy and Mossbauer spectroscopy. The majority of the Fe3+ substitutes at the Co2+ site. The composition of Fe-substituted LiCoPO4 is Li0.92Co0.8Fe2+0.12Fe3+0.08PO4 for a sample of starting composition LiCo0.8Fe0.2PO4.

We investigate polaron formation in olivine LiMnPO4, LiFePO4, LiCoPO4 and LiNiPO4 using a combination of first principles calculations and experimental XPS spectra. We determine that details of the electronic structure near the Fermi energy, relevant to localization of a hole polaron, are not accurately captured using the standard GGA+U methodology and require a hybrid functional approach. We show that polaron formation is possible in all but the Ni-based compound and discuss the possibility of an electronic instability caused by electron withdrawal during delithiation caused by oxygen evolution.

In examining the Li+ charge transfer kinetics at the graphite anode and the lithium nickel cobalt aluminum oxide, LiNi0.80Co0.15Al0.05O2 (NCA), cathode in a full cell, we found that the activation energy, Ea, for the charge transfer at the graphite/electrolyte interface is about 68 kJ/mol, which is consistent with recently reported values. However, the Ea for the charge transfer at the NCA/electrolyte interface is about 50 kJ/mol, which is lower than at the graphite anode. With desolvation as the predominate step for limiting the kinetics and both electrodes subjected to the same electrolyte, the difference in Ea suggests that it is greatly influenced with respect to the nature of the electrode materials and their associated SEIs. This is further confirmed by the examination of Li+ charge transfer at the LiFePO4 (LFP)/electrolyte and the graphite/electrolyte interfaces using a LFP/graphite full cell.

In examining the Li+ charge transfer kinetics at the graphite anode and the lithium nickel cobalt aluminum oxide, LiNi0.80Co0.15Al0.05O2 (NCA), cathode in a complete cell, we found that the activation energy, Ea, for the charge transfer at the graphite/electrolyte interface is about 68 kJ/mol, which is consistent with the recently reported values. However, the Ea for the charge transfer at the NCA/electrolyte interface is about 50 kJ/mol, which is lower than that at the graphite anode. With desolvation as the predominate step for limiting the kinetics and both of the electrodes were subject to the same electrolyte, the difference in Ea suggests that the Ea is influenced greatly with respect to the nature of electrode materials and their associated SEIs. This is further confirmed by the examination of the LiFePO4 (LFP)/electrolyte and the graphite/electrolyte interfaces using a LFP/graphite complete cell.

Charge transfer and charge-discharge kinetics of practical Li-ion cells were investigated using AC impedance and DC pulse methods. Preliminary AC impedance results indicated that the activation energy for charge transfer for high power Li-ion cells employing carbonate-linear ester solvent mixtures was similar to that for cells employing carbonate solvents as reported before. At 100 milliseconds (ms), the pulsed DC impedance indicated that the charge and discharge kinetics were fast and at about the same rate. At 15 seconds (s), the pulsed DC charge resistance was apparently higher than the discharge resistance especially at temperatures below -20 oC. The slower charging kinetics may be limited by the electron transfer step including intercalation and diffusion of Li into the carbonaceous anode.

This article presents letters to the editor commenting on stories and features in previous issues including "Postcard from Drummer," a comment on the connection between rules in the American Paint Horse Association and sending horses to slaughter, and a comment on "Behind the Brand," all of which appeared in the September 2007 issue.

The factors that limit the low temperature performance of Li- ion batteries were examined using an impedance analysis technique. The charge transfer resistance, Rct, obtained by this technique was increased with decreasing temperature following an Arrhenius relationship and it was the predominant resistance at low temperatures. The limiting step in the charge transfer process was discussed by comparing the activation energy of the charge transfer process and the activation energy obtained at a model interface designed by Abe et al. We also explored some electrolyte systems containing ester/carbonate solvent mixtures and/or LiBF4 salt. Lower Rct and activation energy were obtained for MCMB electrode in these electrolytes. Improved low temperature cell performance was also obtained for cells using these electrolytes.

Current research on children and stress supports the belief that children today experience stressful events in a complex developmental-ecological context. Many interdependent elements, including child variables (sex, age, temperament, and developmental stage), family variables (marital status, interactions, child-rearing practices, and socioeconomic status), and variables related to the child's extended social and physical environments (neighborhood, child care, and peers), affect the ways in which children perceive, respond, and cope with stressors (Benswanger, 1982; Honig, 1986). The accuracy of children's perceptions and the development of coping skills, however, vary according to children's cognitive abilities and limitations.

Abstract: Ours is a society in which violence, or the threat of violence, is a common experience for many children. Children's fears of the dark, the boogie man, and the headless Horseman have evolved to include fears of Darth Vadar, meltdown, and nuclear war.

Li plating at the graphite anode and the resultant reaction with electrolyte solvents is a mainstream mechanism for the performance degradation of Li-ion batteries in fast-charge. In this work, we assemble two-electrode and three-electrode graphite/LiNi0.8Co0.1Mn0.1O2Li-ion cells with a relatively low cathode-to-anode capacity ratio to avoid Li plating, finding that the breakage of solid electrolyte interphase on the surface of the graphite anode and the resultant structural exfoliation of graphite and progressive decomposition of electrolyte solvents play a critical role in the performance degradation. Such breakage is suppressed by reducing the particle size of graphite. However, the reduction in the particle size of graphite does not show significant improvement on the charging rate capability of Li-ion cells because the LiNi0.8Co0.1Mn0.1O2cathode is the rate-determining component. Owing to the weak Van der Waals forces between the layered graphene stacks of graphite, the large particle size of graphite can be easily reduced by increasing the milling time in the slurry-making process of the graphite electrode. The results of this work shed new insight into the performance degradation of Li-ion batteries in fast-charge, and suggest a direction for stabilization of capacity retention.

Olivine LiCoPO4(LCP) exhibits a rare combination of high theoretical capacity (167 mAh g?1), excellent thermal stability, and high redox potential (4.8 V vs vs Li/Li+), making it a promising candidate for high voltage lithium batteries. Despite these attractive properties, practical implementation of this electrode chemistry has been limited by stability issues at the cathode-electrolyte interface, including parasitic electrolyte reactions, surface decomposition of the electrode material, and Co dissolution. Carbon coating and substitutions of Co by Fe and other cations improve the performance, however the cycling stability needs further improvement. In an effort to address these issues, we deposited thin, conformal metal oxide surface coatings on substituted LCP powder and investigated the effects of these coatings on the performance of carbon-coated substituted LCP/MCMB graphite full cells with a standard carbonate electrolyte. Remarkably, some of these coatings clearly improved operation of carbon-coated substituted LCP cells as compared to the as-prepared cathode powder. Observed improvements in capacity retention relate to stabilization of the cathode-electrolyte interface and suppression of electrolyte oxidation, as measured by online electrochemical mass spectroscopy (OEMS) of evolved gases within the cell. Together, these results suggest artificial interphases are a viable pathway toward stabilizing LCP and achieving commercial viability.

Provides information on Luisa's Mistletoe or Atkinsonia ligustrina of Australia. Information on the origin of its name; Overview of the plant family of Loranthaceae to where Atkinsonia ligustrina belongs; Habitat and distribution of the plant along the Central Coast hills east of Mount Yengo; Response and vulnerability of Atkinsonia ligustrina on fire.

Early childhood educators are aware of the important role touching plays in child development, nurturance, and guidance. But with attention increasingly focused on child sexual abuse in day care, we need to reexamine our behaviors and the role of touching in child care.

Child care directors' interest in hiring well-qualified staff has increased as issues related to insurance and liability, media-hyped occurrences of child abuse in day care, and quality of child care in general have become of greater concern. Thus, many directors are seeking and developing thorough and innovative methods for interviewing prospective employees (Leak, 1982; Neugebauer, 1982; Sciarra and Dorsey, 1990).

Fortunate child care directors have many volunteers in their centers. Parents, grandparents, student interns, and other community volunteers may work occasionally or regularly in the child care center. Directors should be prepared to host these volunteers by planning in advance for their orientation. This will make the director's task easier and the volunteers' work more meaningful to them and more useful to the children and staff. At the University of Tennessee's Child Development Laboratories we regularly host volunteers with little or no prior experience in child care. Volunteers from the Foster Grandparents Program, from other departments in the university, parents of the children enrolled in the program, as well as our own majors in the beginning stages of their field work, are frequent participants who require orientation and guidelines for working with young children in group care. Because it is not unusual for some volunteers to leave after a semester, training and orientation for new volunteers occurs regularly throughout the year. The information below is offered to directors to promote meaningful involvement of volunteers in their center.

The article discusses the composting operations using windrows and aerated trapezoidal piles of varying depths which highlights options to increase capacity of composting facilities. The Sonoma Compost Co. in Petaluma, California is a yard trimming composting facility owned by Will Bakx which is using turned windrows. The company decided to work with CH2M Hill Inc. to conduct a study to evaluate if aerated static piles could increase the feedstock throughput on the same physical size of the composting facility.

Looks at the efforts of composters to address public complaints concerning the nuisance odors produced by the compost operations in the U.S. Response of composters to complaints raised against them; Risk associated with feedstock preparation; Factors to consider in selecting odor control measures.

Focuses on the development of low-cost composting facilities in North America. Information on a low-cost composting system installed at Rexius Forest By-Products in Eugene, Oregon; Cost of the installed system; Use of a C:N Composting System demonstration unit by Gro-Bark Ltd. of Waterloo, Ontario; Use of sustainable approaches at Fraser Richmond Soil and Fibre Ltd. in Pitt Meadows, British Columbia.

Understanding the factors limiting Li+charge transfer kinetics in Li-ion batteries is essential in improving the rate performance, especially at lower temperatures. The Li+charge transfer process involved in the lithium intercalation of graphite anode includes the step of de-solvation of the solvated Li+in the liquid electrolyte and the step of transport of Li+in the preformed solid electrolyte interphase (SEI) on electrodes until the Li+accepts an electron at the electrode and becomes a Li in the electrode. Whether the de-solvation process or the Li+transport through the SEI is a limiting step depends on the nature of the interphases at the electrode and electrolyte interfaces. Several examples involving the electrode materials such as graphite, lithium titanate (LTO), lithium iron phosphate (LFP), lithium nickel cobalt aluminum oxide (NCA) and solid Li+conductor such as lithium lanthanum titanate or Li-Al-Ti-phosphate are reviewed and discussed to clarify the conditions at which either the de-solvation or the transport of Li+in SEI is dominating and how the electrolyte components affect the activation energy of Li+charge transfer kinetics. How the electrolyte additives impact the Li+charge transfer kinetics at both the anode and the cathode has been examined at the same time in 3-electrode full cells. The resulting impact on Li+charge transfer resistance, Rct, and activation energy, Ea, at both electrodes are reported and discussed.

Focuses on the composting of yard trimmings in Washington. Initial challenges; Cleaning up of contaminants; Composting process modifications; Turned windrow; Other process modifications; Site improvements.

Focuses on wheel loader efficiency in compost operations and how to maximize the use of the equipment in compost plants. Errors in material handling; How to gain efficiency from wheel loader bucket size; Manufacturers and cost examples; Case studies and other attachment options.