Microgravity studies of aggregation in particulate clouds

Aggregation in clouds of submillimeter quartz and volcanic ash particles was studied in microgravity. Particle clouds generated by pulses of air immediately formed electrostatic filamentary aggregates upon cessation of air turbulence. Manual agitation of experiment chambers produced cm-size loose grain clusters which voraciously scavenged free-floating material in their vicinity. A dipole model accounts for these observations. Experimental results have ramifications for the behavior of natural cloud systems and primary accretion of solids in the early solar nebula

Evaluation of the electrochemical O2 concentrator as an O2 compressor

A program was successfully completed to analytically and experimentally evaluate the feasibility of using an electrochemical oxygen (O2) concentrator as an O2 compressor. The electrochemical O2 compressor (EOC) compresses 345 kN/sq m (50 psia) O2 generated on board the space vehicle by the water electrolysis subsystem (WES) in a single stage to 20,700 kN/sq m (3000 psia) to refill spent extravehicular equipment O2 bottles and to eliminate the need for high pressure O2 storage. The single cell EOC designed, fabricated, and used for the feasibility testing is capable of being tested at O2 pressures up to 41,400 kN/sq m (6000 psia). A ground support test facility to test the EOC cell was designed, fabricated, and used for the EOC feasibility testing. A product assurance program was established, implemented, and maintained which emphasized safety and materials compatibility associated with high pressure O2 operation. A membrane development program was conducted to develop a membrane for EOC application. Data obtained using a commercially available membrane were used to guide the development of the membranes fabricated specifically for an EOC. A total of 15 membranes were fabricated

A global protocol for monitoring of coral bleaching

Coral bleaching and subsequent mortality represent a major threat to the future health and productivity of coral reefs. However a lack of reliable data on occurrence, severity and other characteristics of bleaching events hampers research on the causes and consequences of this important phenomenon. This article describes a global protocol for monitoring coral bleaching events, which addresses this problem and can be used by people with different levels of expertise and resources

Photovoltaic stand-alone modular systems, phase 2

The final hardware and system qualification phase of a two part stand-alone photovoltaic (PV) system development is covered. The final design incorporated modular, power blocks capable of expanding incrementally from 320 watts to twenty kilowatts (PK). The basic power unit (PU) was nominally rated 1.28 kWp. The controls units, power collection buses and main lugs, electrical protection subsystems, power switching, and load management circuits are housed in a common control enclosure. Photo-voltaic modules are electrically connected in a horizontal daisy-chain method via Amp Solarlok plugs mating with compatible connectors installed on the back side of each photovoltaic module. A pair of channel rails accommodate the mounting of the modules into a frameless panel support structure. Foundations are of a unique planter (tub-like) configuration to allow for world-wide deployment without restriction as to types of soil. One battery string capable of supplying approximately 240 ampere hours nominal of carryover power is specified for each basic power unit. Load prioritization and shedding circuits are included to protect critical loads and selectively shed and defer lower priority or noncritical power demands. The baseline system, operating at approximately 2 1/2 PUs (3.2 kW pk.) was installed and deployed. Qualification was successfully complete in March 1983; since that time, the demonstration system has logged approximately 3000 hours of continuous operation under load without major incident

Participants’ perspectives of feasibility of a novel group treatment for people with cognitive communication difficulties following acquired brain injury

Purpose: To determine whether treatment was acceptable to participants and perceived as beneficial by exploring the experiences of people with cognitive communication difficulties following acquired brain injury who participated in a novel, group, communication, project-based treatment. The purpose of the treatment was to improve participants’ communication skills and quality of life, by focusing group activity towards the production of a project and by incorporating individualised communication goals into group sessions. Methods: Twenty-one people with acquired brain injury recruited from community settings participated in project-based treatment, which comprised one individual and nine group sessions (of 2-3 people) over six weeks. Structured interviews were conducted post-treatment as part of a broader assessment battery. Interviews were transcribed verbatim and analysed using content analysis to identify codes, categories and themes. Results: Themes identified from the analysis centred around the treatment experience (general experience; group experience; project experience; working on goals) and benefit of treatment (communicative benefit; other benefits; emotional effects; meeting others; something to do). These themes were consistent with the treatment being perceived as acceptable and having initial efficacy for the participant group. Conclusion: The qualitative data presented here provide positive feasibility findings (acceptability and initial efficacy) of project-based treatment for people with acquired brain injury. The results highlight the value of incorporating participants’ views in assessing feasibility in developing novel interventions

A global protocol for monitoring of coral bleaching

Coral bleaching and subsequent mortality represent a major threat to the future health and productivity of coral reefs. However a lack of reliable data on occurrence, severity and other characteristics of bleaching events hampers research on the causes and consequences of this important phenomenon. This article describes a global protocol for monitoring coral bleaching events, which addresses this problem and can be used by people with different levels of expertise and resources.Coral reefs, Bleaching, Mortality, Monitoring

Electrochemical carbon dioxide concentrator: Math model

A steady state computer simulation model of an Electrochemical Depolarized Carbon Dioxide Concentrator (EDC) has been developed. The mathematical model combines EDC heat and mass balance equations with empirical correlations derived from experimental data to describe EDC performance as a function of the operating parameters involved. The model is capable of accurately predicting performance over EDC operating ranges. Model simulation results agree with the experimental data obtained over the prediction range

Electrochemical carbon dioxide concentrator subsystem math model

A steady state computer simulation model has been developed to describe the performance of a total six man, self-contained electrochemical carbon dioxide concentrator subsystem built for the space station prototype. The math model combines expressions describing the performance of the electrochemical depolarized carbon dioxide concentrator cells and modules previously developed with expressions describing the performance of the other major CS-6 components. The model is capable of accurately predicting CS-6 performance over EDC operating ranges and the computer simulation results agree with experimental data obtained over the prediction range

The educational potential of the Harmony Project

This research, funded by Canterbury Christ Church University, involved semi-structured interviews with senior leaders from ten schools in England who are engaging with principles of Harmony. Interviews were conducted between May and July 2019 by research intern Julie Marshall and the project was led by Nicola Kemp and Alan Pagden. The aim was to explore the educational potential of the Harmony approach in different school contexts

Studies in Lead Absorption and Lead Poisoning

(1) The history, biochemistry and physiology of lead are discussed, and blood lead values of normal healthy individuals with no lead hazard, healthy lead workers, hospital patients not suffering from plumbism with known lead contact, and cases of clinical plumbism are recorded and contrasted. (2) The aetiology, pathology, clinical findings and treatment of plumbism are discussed. (3) Seven cases of clinical plumbism of industrial origin are described. Three individuals showing laboratory evidence of increased lead absorption of industrial origin, associated with ill-defined symptoms, are also recorded. (4) Lead poisoning arising from the drinking of lead-contaminated water, resulting in the death of a woman, is described, together with investigations carried out to detect the cause of the poisoning. (5) A case of severe plumbism following the ingestion of 110 gr. lead acetate for the purpose of criminal abortion is recorded and discussed