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Replacing state-of-the-art graphite with metallic Li anodes could dramatically increase the energy density of Li-ion technology. However, efforts to achieve uniform Li plating and stripping in conventional liquid electrolytes have had limited success. An alternative approach is to use a solid electrolyte to stabilize the Li interface during cycling. One of the most promising solid electrolytes is Li 7 La 3 Zr 2 O 12 , which has high ionic conductivity at room temperature, high shear modulus and chemical and electrochemical stability against Li. Despite these properties, Li filament propagation has been observed through LLZO at current densities below what is practical. By combining recent achievements in reducing interface resistance and optimizing microstructure, we demonstrate Li cycling at current densities competitive with Li-ion. Li|LLZO|Li cells are capable of cycling at up to 0.9 ± 0.7 mA cm −2 , 3.8 ± 0.9 mA cm −2 , and 6.0 ± 0.7 mA cm -2 at room temperature, 40 and 60 °C, respectively. Extended stability is shown in Li plating/stripping tests that passed 3 mAh cm −2 charge per cycle for a cumulative capacity of 702 mAh cm −2 using a 1 mA cm −2 current density. These results demonstrate that solid-state batteries using metallic Li anodes can approach charge/discharge rates and cycling stability comparable to SOA Li-ion.

A novel sol-gel chemistry approach was developed to enable the simple integration of a cast-in-place, ambiently-dried insulation into high temperature applications. The insulation was silica-based and synthesized using methyltrimethoxysilane (MTMS) as the precursor. MTMS created a unique silica microstructure that was mechanically robust, macroporous, and superhydrophobic. To allow for casting into and around small, orthogonal features, zirconia fibers were added to increase stiffness and minimize contraction that could otherwise cause cracking during drying. Nano-sized titania powder was incorporated as an opacifier to reduce radiative heat transport. To assess relevance to high temperature thermoelectric generator technology, a comprehensive set of materials characterization experiments were conducted. The silica gel was thermally stable, retained superhydrophobicity with a water contact angle >150°, and showed a high electrical resistance >1 GΩ, regardless of heating temperature (up to 600 °C in Ar for 4 h). In addition, The silica-based thermal insulation exhibited a Young's modulus ∼3.7 MPa and a low thermal conductivity

The elastic modulus, fracture toughness, ionic conductivity, Li and water stability of dense (~ 97%) fine-grain (~ 10 μm) Li 1.2 Zr 1.9 Sr 0.1 (PO 4 ) 3 (LZSP) consolidated by reactive hot-pressing was investigated. Low values of elastic modulus (25.2 and 40.9 GPa), fracture toughness (0.29 and 0.37 MPa-m 1/2 ), total conductivity (2.1 × 10 − 5 S/cm) at room temperature were exhibited as a result of the presence of microcracks formed during cooling from the hot-pressing temperature. The lattice conductivity of LZSP is 0.85 × 10 − 4 S/cm with an activation energy for bulk conductivity of 0.29 eV. The results of Li/LZSP/Li cell impedance as a function of time and surface examination suggest that LZSP is not stable against metallic lithium. The results of the water stability test suggest that LZSP is a possible membrane for use in aqueous Li-Air cells. The results of this study reveal for the case of lithium zirconium phosphates are as follows: 1] a small grain size is required to prevent microcracking to avoid a reduction in total conductivity and mechanical properties and 2] even though they do not contain a transition metal cation they are not stable against Li at room temperature.

The use of LiCoPO4 as a Li-ion cathode material can enable high energy 5 V batteries. However, LiCoPO4 shows limited cycle life and much less than theoretical energy density. In order to address these shortcomings, Fe, Cr and Si substituted-LiCoPO4 (Cr,Si-LiCo0.9Fe0.1PO4) was investigated as an improved LiCoPO4 based cathode material. Fe substitution greatly improves the cycle life and increases the energy density. Cr substitution further increases the energy density, cycle life and rate capability. Si substitution reduces the reactivity of the cathode with electrolyte thereby increasing cycle life. In combination, the substituents lead to a LiCoPO4 based cathode material with no capacity fade over 250 cycles in Li/Cr,Si-LiCo0.9Fe0.1PO4 half cells, a discharge capacity of 140 mAh g−1 at C/3 at an average discharge voltage of 4.78 V giving an energy density of 670 Wh per kg of cathode. In graphite/Cr,Si-LiCo0.9Fe0.1PO4 full Li-ion cells, the cathode material shows an energy density of 550 Wh per kg of cathode material at 1C rate for the initial cycles and 510 Wh per kg of cathode material at the 250th cycle.

This paper is concerned with the study of the equilibrium exchange of ammonium ions with two natural zeolite samples sourced in Australia from Castle Mountain Zeolites and Zeolite Australia. A range of sorption models including Langmuir Vageler, Competitive Langmuir, Freundlich, Temkin, Dubinin Astakhov and Brouers–Sotolongo were applied in order to gain an insight as to the exchange process. In contrast to most previous studies, non-linear regression was used in all instances to determine the best fit of the experimental data. Castle Mountain natural zeolite was found to exhibit higher ammonium capacity than Zeolite Australia material when in the freshly received state, and this behavior was related to the greater amount of sodium ions present relative to calcium ions on the zeolite exchange sites. The zeolite capacity for ammonium ions was also found to be dependent on the solution normality, with 35–60% increase inuptake noted when increasing the ammonium concentration from 250 to 1000 mg/L. The optimal fit ofthe equilibrium data was achieved by the Freundlich expression as confirmed by use of Akaikes Information Criteria. It was emphasized that the bottle-point method chosen influenced the isotherm profile in several ways, and could lead to misleading interpretation of experiments, especially if the constant zeolite mass approach was followed. Pre-treatment of natural zeolite with acid and subsequently sodium hydroxide promoted the uptake of ammonium species by at least 90%. This paper highlighted the factors which should be taken into account when investigating ammonium ion exchange with natural zeolites.

Oils derived from vegetable oils tend to not meet the standards for industrial lubricants because of unacceptable low temperature properties, pour point (PP) and/or cloud point (CP). However, a catalytic amount of perchloric acid with oleic and coconut (coco) fatty acids produced a coco-oleic estolide. The resulting coco-oleic estolide was separated into two components based on the extent of oligomerization: coco-oleic dimer estolide and coco-oleic trimer plus estolide. These two estolides were then esterified with a series of different branched alcohols; the coco-oleic dimer estolide esters had the lowest PP = −45 °C when with esterified 2-hexyldecanol and PP = −39 °C with 2-octyldodecanol. The best CP performer from the same series was the 2-octyldodecanol ester, CP = −37 °C. The coco-oleic trimer plus estolide esters had slightly higher PPs (−24 to −39 °C) with the same alcohols. The viscosities and viscosity indexes were as expected in terms of trends. The coco-oleic dimer estolide esters ranged 27.5–51.7 cSt @ 40 °C and 3.0–9.5 cSt @ 100 °C, whereas the coco-oleic trimer plus estolide esters ranged 120.8–227.7 cSt @ 40 °C and 17.9–29.4 cSt at 100 °C for the same series as the dimer esters. Outside the series tested, an iso-stearyl trimer plus ester had the highest reported viscosity of 417.3 cSt @ 40 °C and 38.9 cSt @ 100 °C. Because these new branched estolide esters have excellent viscosity and low temperature physical properties without the addition of other chemicals, they minimize the effect on the environment while replacing nonrenewable products.

LiCoPO 4 is a promising cathode material for use in high voltage Li-ion batteries. One of the problems with LiCoPO 4 is limited cycle life. One possible cause for the limited cycle life of LiCoPO 4 is mechanical degradation. As a consequence, the mechanical properties, elastic modulus, E , and fracture toughness, K IC , of hot-pressed dense (~98%) polycrystalline (15–20 μm) single phase LiCoPO 4 were investigated. E for the hot-pressed LiCoPO 4 specimen is ~137 GPa while the E value for the LiCoPO 4 specimen after annealing at 600 °C is ~106 GPa. The fracture toughness of the hot-pressed LiCoPO 4 sample is ~0.41 MPa m 1/2 , which increased to ~0.53 MPa m 1/2 after annealing. These low K IC values reveal that LiCoPO 4 is a brittle material. It is believed that the decrease in E and increase in K IC with annealing is associated with a reduction in residual stress.

LiCoPO 4 is a promising cathode material to enable high energy, abuse tolerant Li-ion batteries. However, LiCoPO 4 has relatively poor electronic conductivity which may be improved by chemical substitution. In this work, the ionic and electronic conductivities of dense, polycrystalline LiCoPO 4 and Fe 2+ /Fe 3+ -substituted LiCoPO 4 (Li 1− x Co 0.9 Fe 0.1 PO 4 ) are measured and compared. Both materials are predominantly ionic conductors with relatively good bulk ionic and relatively poor electronic conductivities. Li 1− x Co 0.9 Fe 0.1 PO 4 exhibits both higher bulk ionic and electronic conductivity. The increased bulk ionic conductivity of Li 1− x Co 0.9 Fe 0.1 PO 4 is believed to originate mainly from extra Li vacancies and the increased electronic conductivity is believed to originate mainly from creating more mobile hole polarons compared to LiCoPO 4 as a result of Fe 2+ /Fe 3+ substitution.

Vegetable oil-based oils usually fail to meet the rigorous demands of industrial lubricants by not having acceptable low temperature properties, pour point (PP) and/or cloud point (CP). Oleic estolide was produced from oleic fatty acid and a catalytic amount of perchloric acid. The oleic estolide was then esterified with a series of 16 different alcohols that were either branched or linear-chained. The new estolide esters physical properties were recorded and evaluated as a potential industrial lubricant. The linear-chain esters had higher low temperature properties (PP = −9 to −33 °C) but still compete well with other commercial bio-based materials. The oleic estolide ethyl ester yielded the best PP at −33 °C for the linear-chain series. The branched alcohol produced the best PP (−24 to −39 °C) and CP (−30 to

OBJECTIVES To assess the prognostic effect of perineural invasion (PNI) for patients undergoing external beam radiotherapy for prostate cancer. METHODS We evaluated 657 consecutive patients who had undergone external beam radiotherapy for clinically localized prostate cancer. The clinical/treatment parameters used for analysis included PNI, clinical stage, biopsy Gleason score, pretreatment prostate-specific antigen, radiation dose, and androgen deprivation. The primary endpoint was biochemical recurrence defined by the Radiation Therapy Oncology Group-American Society for Therapeutic Radiology Oncology Phoenix consensus; the secondary endpoint was prostate cancer death. RESULTS Of 586 men with a minimum of 24 months of follow-up, 112 (19.1%) had PNI present in the biopsy specimen. When patients were stratified into risk groups using the National Comprehensive Cancer Network criteria, PNI was more prevalent in patients within higher risk groups (6.8% in low-risk versus 18.3% in intermediate-risk versus 30.1% in high-risk groups; P

Prader-Willi syndrome (PWS) is a genetic disorder characterized by hyperphagia and food preoccupations. Researchers indicate that individuals with PWS, including young children, exhibit food and non-food-related compulsions. Normative rituals are also often present among typically developing preschoolers. However, it is unclear how these behaviors affect the child. Although preschoolers with PWS exhibit more types of rituals than other populations, it is uncertain if the severity of these behaviors differs from the rituals experienced during normative development. Thus, the purpose of this research was to determine whether the ritualistic behaviors exhibited by preschoolers with PWS differ in severity from those exhibited during normative development. We also sought to identify whether non-food ritualistic behavior was related to the hyperphagia in PWS. Parents of 68 children with PWS, 86 typically developing children, and 57 children with developmental delays completed questionnaires on rituals and eating behavior. Children with PWS exhibited more severe ritualistic behavior than typically developing children but not other children with developmental delays. However, the severity of non-food-related rituals was related to the severity of eating behavior in PWS. We hypothesize that this link between hyperphagia and non-food-related compulsivity may share a common underlying neurobiological mechanism.

We tested the influence of (1) the homelike appearance of residences, (2) residential staff-members' attitudes about people with mental retardation and (3) Client IQ on the number of activities adults clients with mental retardation conducted in their community. We tested the hypothesis these three variables exerted their influence by promoting positive staff-member interactions with clients. This was assessed by measuring the duration of Staff-initiated Social Interactions with residential clients. In our initial path model, Residential Homelikeness, Positive Staff Attitudes and Client IQ had no significant direct effect on Community Activities. In the final model, however, Residential Homelikeness and Positive Staff Attitudes exerted a statistically significant influence on Staff-initiated Social Interactions with clients, which in turn, exerted a statistically significant influence on Community Activities. This model illustrated: (1) the nearly equal influence of Staff Attitudes and architectural characteristics on Staff-initiated Interactions; and (2) the role of Staff-initiated Interactions in mediating the influence of Residential Homelikeness on community participation by adults with developmental disabilities.

Twelve pigeons key-pecked under a multiple variable interval 15-s, 150-s schedule of food reinforcement. The effects of methadone were studied alone and in combination with chronic daily administration of either imipramine (IMI) or desipramine (DMI). Chronic IMI was also given following reductions in response rates by unsignalled delay-to-reinforcement (UDR). Acute administration of methadone produced dose-dependent reductions in response rates under both schedules of reinforcement. Chronic daily administration of IMI or DMI alone did not result in lasting changes in baseline responding. When administered in combination, chronic daily IMI significantly attenuated the rate-reducing effects of methadone, whereas neither a low nor a high dose of chronic daily DMI was effective. The same dose of chronic daily IMI failed to ameliorate response rate reductions under delayed reinforcement. The behavioral and neurochemical specificity of the antidepressant effect is discussed.

Using a two-lever drug discrimination procedure, two groups of four rats each were trained to discriminate the stimulus effects of 1.0 U/kg insulin or 125 mg/kg 2-deoxy- D -glucose (2-DG) from saline. A third group was trained to discriminate food deprivation produced by feeding 23 h prior to sessions from satiation produced by feeding 2 h prior to sessions. Differential responding was a direct function of dose or deprivation level in each group. Rats trained to discriminate insulin responded as if they had received insulin when they received 2-DG and vice versa. Insulin and 2-DG produced deprivation-appropriate responding in two of four rats trained to discriminate food deprivation. Low insulin and 2-DG doses produced drug-appropriate responding in rats deprived 47 h, but not in rats deprived 23 h. Blood glucose level was altered by the training doses of insulin and 2-DG, but not by 23-h deprivation. These results indicate that operations that induced feeding produce discriminable stimuli, and that these effects overlap or interact. Thus, drug discrimination procedures can be useful in the analysis of ingestive behavior.

Twelve pigeons key-pecked under a multiple variable interval 15-second, variable interval 150-second schedule of food reinforcement. Effects of two opioid drugs, buprenorphine and methadone, were determined alone and in combination with chronic daily administration of the antidepressants doxepin or bupropion. Methadone initially produced dose-dependent key-pecking rate reductions when administered acutely, prior to the session, while buprenorphine produced key-pecking rates that reached a plateau at 50-80% of baseline rate and were not reduced further by higher doses. Neither doxepin nor bupropion, given alone, had lasting effects on key-pecking rates. Chronic daily doxepin administration significantly attenuated methadone-induced response rate reductions. Bupropion reduced the effect of the highest methadone dose, but this effect was mitigated by the development of opioid tolerance. Unlike bupropion, doxepin interfered with the development of opioid tolerance. Neither antidepressant systematically altered effects of buprenorphine on key-pecking.

Stereotypic behavior is one of the more common disturbed behaviors displayed by people who are developmentally disabled. This study evaluated the indirect effects on stereotypic frequency when the value of a concurrent fixed-interval reinforcement schedule for adaptive behavior was varied. Three profoundly mentally retarded adults performed a simple adaptive task reinforced under a fixed-interval schedule. The reinforcement schedule value was varied from fixed-interval 15 to 90, and 180 seconds after schedule control under each condition was demonstrated. The dependent measure was the frequency of stereotypic behavior. Stereotypic behavior increased in direct relation to the interval length. The theoretical and practical implications of treating stereotypies as an adjunctive behavior partially controlled by the reinforcement frequency for adaptive behaviors are discussed.

The effects of methadone hydrochloride on lever pressing rats maintained under multiple fixed-interval and fixed-ratio, or multiple variable-interval and variable-ratio reinforcement schedules equated for reinforcement density were examined. Under a multiple fixed-interval, fixed-ratio schedule overall response rate was decreased during both components but was most affected under the ratio schedule. Response rate decreases were due primarily to changes in running rate rather than pause time. Under a multiple variable-interval, variable-ratio schedule, overall response rate was also decreased by methadone, with the greatest decrease again occurring during the ratio schedule. These schedule-specific methadone effects are not due to differences in reinforcement frequency. Evidence for rate-dependency with methadone is not consistent across subjects.

Twelve pigeons were initially trained under either a fixed-ratio (FR) 50 or differential-reinforcement-of-low-rate (DRL) 10-sec schedule of food presentation. After 50 sessions of exposure to the foregoing schedules all pigeons key pecked under a fixed-interval (FI) 90-sec schedule. Key-peck rates differed as a function of schedule history, with FR-history subjects responding at significantly higher rates under the FI schedule than DRL-history subjects. To better compare methadone's rate-altering effects on baseline response rates, 8 naive pigeons were trained from the outset to key peck under an FI 90-sec schedule and were subsequently divided into 2 groups based on overall response rates (groups FI-H and FI-L). After at least 40 sessions under the FI schedule methadone dose-response curves were determined at doses of 0.6, 1.2 and 2.4 mg/kg. Low and intermediate methadone doses did not effect key-peck rates by pigeons with an FR history compared to significant rate decreases by pigeons having comparable rates but without a history of responding under an FR schedule (group FI-H). No differential effects following methadone were observed in low-rate subjects (DRL history and FI-L). When methadone (9.0 and 12.0 mg/kg/day) was administered chronically, response rates of all subjects were initially suppressed, with FI control subjects showing more complete recovery of drug-free baselines than either FR- or DRL-history groups. Naloxone (1.0 mg/kg) reversed methadone's rate-decreasing effects, although these actions were significantly less in subjects with prior experience under DRL schedules. Following completion of the chronic phase, and when subjects had been drug free for at least 14 sessions, the methadone dose-response curve was redetermined. The differential effects of methadone associated with reinforcement history were no longer evident, suggesting that a drug history can interact with a schedule history. These experiments add to the growing body of evidence indicating that prior experience can influence the behavioral actions of drugs independent of control rate of responding. Moreover, the data reveal that the influence of reinforcement schedule history depends on whether drugs are administered acutely or chronically.

In a behavioral treatment program for acute psychiatric patients, points were earned for adaptive behavior (e.g. self-care, attending ward activities) and lost for maladaptive behavior (e.g. assaults, verbal abuse). Points earned could be spent for a variety of goods and services (e.g. passes, extra staff time). Statistically significant correlations were found between MMPI scale scores and point-earning behavior. High scores on the F , 5, 6 and 8 scales were associated with low point gain for adaptive behavior, high point loss for maladaptive behavior, a high proportion of points spent to points earned, and a low overall net point earnings. Low score on F scale in combination with high score on 2 scale best predicted point-gain behavior, whereas high score on 8 scale in combination with low score on 1 scale best predicted point-loss behavior. Overall net points were best predicted by low score on F scale in combination with high scores on 0 and 9 scales. When subjects were grouped into common psychiatric profile types, differences were found in point-gain behaviors for items related to personal care and attending ward activities. At least some of these differences could be attributed to two factors: high scores on the 2, 3 and 7 scales were associated with higher than average point earnings, while high scores on the 8 scale were associated with lower than average point earnings.

Effects in the rat of chronic postweaning exposure to 50, 300, or 1000 ppm lead acetate in drinking water were assessed on responding maintained by a fixed-interval 30-s food reinforcement schedule. On this schedule, food reinforcement followed the first lever press response occurring at least 30 s after the preceding food delivery. Exposure to 50 and 300 ppm lead acetate increased response rates and intersubject variability, while latency, or time to initiation of responding in the interval, decreased. Exposure to 1000 ppm initially decreased rates and increased latency values. Following termination of exposure to 50 ppm, response rates and latency values gradually returned to control levels. Behavioral effects produced by exposure to 50 and 300 ppm lead were similar in magnitude but varied in time to onset and decline, suggesting time-dependent, rather than concentration-dependent effects of lead.

The effectiveness of social isolation, aversion-relief treatment, one-to-one monitoring with point earning and point loss contingencies, and no-programmed contingencies were compared in treating a 22-year-old mildly retarded woman with Prader-Willi Syndrome for obesity. While the patient lost some weight during contingent social isolation and aversion therapy, her weight increased rapidly on discontinuing these procedures. The patient lost 44 lb. over 5 months of 1:1 monitoring with immediate point-gain and point-loss contingencies and dropped 8 more pounds over 3 succeeding months in a less rigorously controlled setting.

Twenty-one-day-old male weanling rats were started on a chronic exposure regimen of 0, 100, or 300 ppm lead acetate in distilled water. They were trained to press a lever for food reward at 55 days of age. Subsequently, a schedule of differential reinforcement of minimum response duration was imposed, in which only lever press durations greater than or equal to a required duration were followed by food presentation. Under these conditions, response durations of control animals approximated schedule requirements; lead treatment shortened response durations. Treated rats also paused for longer periods before initiating responses. Differences between the treated groups were not apparent. Individual differences were observed in susceptibility to lead-induced behavioral changes. Some treated animals tended to show greater session-to-session variability than did controls. Even when a tone was added to signal that the required duration had elapsed, certain treated rats failed to show modal response duration values consistent with the schedule requirement. Failure to improve performance of lead-treated rats by external stimulus control has not previously been reported.

Schedule-induced polydipsia was established by maintaining 4 male Sprague-Dawley rats on concurrent variable interval 1 min food reinforcement and continuous water reinforcement. Five ethanol concentrations (2, 4, 8, 16, and 32% W/V) were substituted for water. The number of liquid reinforcements and volume of liquid consumed varied inversely with ethanol concentration while the quantity of ethanol intake varied directly with the concentration. Ethanol reinforcements were above water control levels during the first 10 min ethanol was present. For the same interval increases occurred in the number of ethanol, but not water reinforcements when each concentration was presented a second time. Decreases occurred in the food baseline as a function of concentration with intermediate concentrations having the greatest effect. These decreases were greater the second time the ethanol concentrations were presented.

Regular insulin in doses greater than 0.1 units/kg produced dose-dependent maximum decreased in plasma glucose levels of food deprived rats 60 minutes after injections. FR 1 food reinforced lever pressing showed a dose-dependent, food deprivation-dependent and pretreatment time-dependent decrement in operant responding. Insulin suppression of responding was reduced when subjects were partially food satiated. FR 1 water reinfroced behavior also showed a dose-dependent and pretreatment time-dependent decrement in lever pressing. VI 1 min food reinforced level pressing similarly showed a dose-dependent and pretreatment time-dependent decrement in responding. Thus, effects of insulin on operant responding were largely independet of type of reinforcer and schedule of reinforcement. Further, the failure to observe a consistent increase in responding with insulin did not support the view that insulin induces a state comparable to increased food deprivation levels. These findings suggest that the spectrums of effects of insulin and food deprivation differ.