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PubMed2003

Solar flair.

Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams.

Conservation of Natural Resources↗
PubMed1987

Wave energy and intertidal productivity.

In the northeastern Pacific, intertidal zones of the most wave-beaten shores receive more energy from breaking waves than from the sun. Despite severe mortality from winter storms, communities at some wave-beaten sites produce an extraordinary quantity of dry matter per unit area of shore per year. At wave-beaten sites of Tatoosh Island, WA, sea palms, Postelsia palmaeformis, can produce > 10 kg of dry matter, or 1.5 x 10(8) J, per m(2) in a good year. Extraordinarily productive organisms such as Postelsia are restricted to wave-beaten sites. Intertidal organisms cannot transform wave energy into chemical energy, as photosynthetic plants transform solar energy, nor can intertidal organisms "harness" wave energy. Nonetheless, wave energy enhances the productivity of intertidal organisms. On exposed shores, waves increase the capacity of resident algae to acquire nutrients and use sunlight, augment the competitive ability of productive organisms, and protect intertidal residents by knocking away their enemies or preventing them from feeding.

Journal Article↗
PubMed2002

Use of thermodynamic orientors to assess the efficiency of ecosystems: a case study in the lagoon of Venice.

So-called orientors have been introduced at the interface between ecology and thermodynamics. Two have been chosen here to compare the characteristics of five ecological systems: exergy, which is related to the degree of organization of a system and represents the biogeochemical energy of a system, and emergy, which is defined as the total amount of solar energy directly or indirectly required to generate a product or a service. They represent two complementary aspects of a system: the actual state and the past work needed to reach that state. The ratio of exergy to the emergy flow indicates the efficiency of an ecosystem in producing or maintaining its organization. The main system under study is a portion of the Venice Lagoon, which is used as a fish farming basin. Four other aquatic ecosystems were considered for comparison. Results show that the ecosystem within the Venice Lagoon is the one with the highest efficiency in transforming the available inputs in organization of the system. This fact is due to human intervention, which is very limited but also very effective.

Ecosystem↗
PubMed2006

Solar wind neon from Genesis: implications for the lunar noble gas record.

Lunar soils have been thought to contain two solar noble gas components with distinct isotopic composition. One has been identified as implanted solar wind, the other as higher-energy solar particles. The latter was puzzling because its relative amounts were much too large compared with present-day fluxes, suggesting periodic, very high solar activity in the past. Here we show that the depth-dependent isotopic composition of neon in a metallic glass exposed on NASA's Genesis mission agrees with the expected depth profile for solar wind neon with uniform isotopic composition. Our results strongly indicate that no extra high-energy component is required and that the solar neon isotope composition of lunar samples can be explained as implantation-fractionated solar wind.

Journal Article↗
PubMed2006

Flexible solar-cell from zinc oxide nanocrystalline sheets self-assembled by an in-situ electrodeposition process.

Zinc oxide nanocrystalline sheets were self-assembled on a flexible polymer substrate to act as the electrode of dye-sensitized solar cells by an in situ-construction electrodeposition process. It was discovered that the nanosheet-based solar cell exhibited better performance than a nanoparticle-based solar cell or a well-oriented nanowire-based solar cell. The nanosheet microstructure has advantages which include the depression of loss during photoelectron transport, the increase of dye compound adsorption, and the enhance of incident light capture. As a result, the performance of dye-sensitized solar cells can be obviously improved. This success provides a feasible bottom-up approach for integrating a solar cell together with nanodevices and microcircuits on a flexible substrate which can work with self-supplied solar energy.

Electrochemistry↗
PubMedDate not supplied

Energy conservation in large hospitals & medical centers.

Energy conservation programs can save money for medical centers. The necessary engineering capability to evaluate these methods can be provided by Clinical Engineering staffs since the analytical ability of the Clinical Engineer is directly transferable to energy conservation programs. Several conservation methods are applicable to hospitals and deserve consideration. Cogeneration can provide significant energy conservation without any sacrifice in comfort. Solar energy is well suited to hospitals and can provide good publicity as well as energy savings. Finally, better electronic and pneumatic controls for heating, air conditioning and ventilation can provide large energy savings at moderate cost.

Conservation of Energy Resources↗
PubMed1999

Enhancement of solar water pasteurization with reflectors.

A simple and reliable method that could be used in developing countries to pasteurize milk and water with solar energy is described. A cardboard reflector directs sunshine onto a black jar, heating water to pasteurizing temperatures in several hours. A reusable water pasteurization indicator verifies that pasteurization temperatures have been reached.

Animals↗
PubMed2003

Recycling of hazardous solid waste material using high-temperature solar process heat. 2. Reactor design and experimentation.

A novel high-temperature solar chemical reactor is proposed for the thermal recycling of hazardous solid waste material using concentrated solar power. It features two cavities in series, with the inner one functioning as the solar absorber and the outer one functioning as the reaction chamber. The solar reactor can handle thermochemical processes at temperatures above 1,300 K involving multiphases and controlled atmospheres. It further allows for batch or continuous mode of operation and for easy adjustment of the residence time of the reactants to match the kinetics of the reaction. A 10-kW solar reactor prototype was designed and tested for the carbothermic reduction of electric arc furnace dusts (EAFD). The reactor was subjected to mean solar flux intensities of 2,000 kW m(-2) and operated in both batch and continuous mode within the temperature range of 1,120-1,400 K. Extraction of over 90% of the toxic compounds originally contained in the EAFD was achieved while the condensable products of the off-gas contained mainly Zn, Pb, and Cl. The use of concentrated solar energy as the source of process heat offers the possibility of converting hazardous solid waste material into valuable commodities for processes in closed and sustainable material cycles.

Conservation of Natural Resources↗
PubMed1991

Terrestrial approaches to integration of waste treatment.

Solar energy driven physical, chemical and biological recycling of nutrients is the characteristic of the Earth-Sun system which permits life on earth to continue. Natural recycle of nutrients on Earth may literally require thousands or even millions of years to be complete, but for modern civilization to continue on Earth or in space, mankind must take charge of, and accelerate, the recycle of all essentials of life. In this paper we describe studies of two accelerated recycle systems; a solar powered energy system and an integrated feed lot. Both systems require special infrastructures permitting the accelerated physical, chemical and biological processing to occur. These systems do not integrate respiratory carbon dioxide as must be done in a complete closed ecological life support system (CELSS). The Algatron, a more complete system involving microalgal bacterial waste treatment with water, oxygen and carbon dioxide recycle was designed for use in Space Stations over 20 years ago.

Bacteria↗
PubMed2004

Effect of temperature and temperature fluctuation on thermophilic anaerobic digestion of cattle manure.

The influence of temperature, 50 and 60 degrees C, at hydraulic retention times (HRTs) of 20 and 10 days, on the performance of anaerobic digestion of cow manure has been investigated in completely stirred tank reactors (CSTRs). Furthermore, the effect of both daily downward and daily upward temperature fluctuations has been studied. In the daily downward temperature fluctuation regime the temperatures of each reactor was reduced by 10 degrees C for 10 h while in the daily upward fluctuation regime the temperature of each reactor was increased 10 degrees C for 5 h. The results show that the methane production rate at 60 degrees C is lower than that at 50 degrees C at all experimental conditions of imposed HRT except when downward temperature fluctuations were applied at an HRT of 10 days. It also was found that the free ammonia concentration not only affects the acetate-utilising bacteria but also the hydrolysis and acidification process. The upward temperature fluctuation affects the maximum specific methanogenesis activity more severely as compared to imposed downward temperature fluctuations. The results clearly reveal the possibility of using available solar energy at daytime to heat up the reactor(s) without the need of heat storage during nights, especially at an operational temperature of 50 degrees C and at a 20 days HRT, and without the jeopardising of the overheating.

Ammonia↗
PubMed2004

Global patterns in human consumption of net primary production.

The human population and its consumption profoundly affect the Earth's ecosystems. A particularly compelling measure of humanity's cumulative impact is the fraction of the planet's net primary production that we appropriate for our own use. Net primary production--the net amount of solar energy converted to plant organic matter through photosynthesis--can be measured in units of elemental carbon and represents the primary food energy source for the world's ecosystems. Human appropriation of net primary production, apart from leaving less for other species to use, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services. Here we present a global map showing the amount of net primary production required by humans and compare it to the total amount generated on the landscape. We then derive a spatial balance sheet of net primary production 'supply' and 'demand' for the world. We show that human appropriation of net primary production varies spatially from almost zero to many times the local primary production. These analyses reveal the uneven footprint of human consumption and related environmental impacts, indicate the degree to which human populations depend on net primary production 'imports' and suggest policy options for slowing future growth of human appropriation of net primary production.

Atmosphere↗
PubMed2004

Use of rural energy resources and eco-environmental degradation in Tibet.

Cattle dung, firewood, and crop straw have being used as survival necessities by farmers and herdsmen for thousands of years in Tibet. Until recently such biotic energy source still constitutes more than 92 per cent of total rural energy consumption due to lack of petroleum, coal and new alternative energy sources. As a result, environmental degradation such as land desertification, soil erosion, grassland degradation and soil fertility reduction is increasingly aggravated, the area of desertified land has increased 1467.5 km2 from 1991 to 1997. Degraded area of grassland has reached 2.60 x 10(7) hm2, increased by 116.1% from 1987 to 1996. To prevent further deterioration of eco-environment in Tibet great efforts should be made to make full use of ample solar energy, wind energy and other biotic energy of the Qinghai-Tibet Plateau. The solar cooking stoves and solar hothouse, expand forest area and replace existing abiotic energy sources with firewood forest should be popularized. This is an urgent task to protect the eco-environment of Tibet today.

Animals↗
PubMed2005

Nanowire dye-sensitized solar cells.

Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport, a slow mechanism that can limit device efficiency, especially at longer wavelengths. Here we introduce a version of the dye-sensitized cell in which the traditional nanoparticle film is replaced by a dense array of oriented, crystalline ZnO nanowires. The nanowire anode is synthesized by mild aqueous chemistry and features a surface area up to one-fifth as large as a nanoparticle cell. The direct electrical pathways provided by the nanowires ensure the rapid collection of carriers generated throughout the device, and a full Sun efficiency of 1.5% is demonstrated, limited primarily by the surface area of the nanowire array.

Coloring Agents↗
PubMed2004

Is rangeland agriculture sustainable?

The objective of this paper is to examine the sustainability of rangeland agriculture (i.e., managed grazing) on a world-wide basis, with a focus on North America. Sustainability is addressed on three fronts: 1) ecological, 2) economic, and 3) social acceptance. Based on previous and on-going research, we suggest that employment of science-based rangeland grazing management strategies and tactics can ensure ecological sustainability. The formidable challenge in employing such technology centers around the need to balance efficiency of solar energy capture and subsequent harvest efficiencies across an array of highly spatially and temporally variable vegetation growing conditions using animals that graze selectively. Failure to meet this fundamental challenge often accelerates rangeland desertification processes, and in some instances, enhances rate and extent of the invasion of noxious weeds. We also suggest that the fundamental reason that ecologically sound grazing management technologies are often not employed in the management of grazed ecological systems is because social values drive management decisions more so than ecological science issues. This is true in both well-developed societies with substantial economic resources and in less-developed societies with few economic resources. However, the social issues driving management are often entirely different, ranging from multiple-use issues in developed countries to human day-to-day survival issues in poorly developed countries. We conclude that the long-term sustainability of rangeland agriculture in 1) developed societies depends on the ability of rangeland agriculturalists to continually respond in a dynamic, positive, proactive manner to ever-changing social values and 2) less-developed societies on their ability to address the ecological and social consequences arising from unsustainable human populations before the adoption of science-based sustainable rangeland management technologies.

Agriculture↗
PubMed1996

Spectral composition of light and plant productivity.

Among other problems the Institute of Biophysics is working on the development of physiological and fundamental aspects of intensive light cultivation of higher plants. These technologies can be used in life support systems for stationary space station such as a Lunar base, a planetary base or a large orbital station. The source of energy may be the Sun or a nuclear reactor. In certain conditions, such sources of energy allow the use of a very broad range of irradiance of plants, in particular in the light energy range up to 2-3 times the solar energy (up to 100-1200 W/m2 PAR). Our Institute was the first to show that under such a high irradiance, some plants (radish, wheat, for example) can actively photosynthesize and exhibit high productivity on a sowing area basis. These results were later confirmed in the laboratory of Prof. Salisbury (USA).

Cucumis sativus↗
PubMed2006

Asbestos as a possible major cause of malignant lung tumors (including small cell carcinoma, adenocarcinoma & mesothelioma), brain tumors (i.e. astrocytoma & glioblastoma multiforme), many other malignant tumors, intractable pain including fibromyalgia, & some cardio-vascular pathology: Safe & effective methods of reducing asbestos from normal & pathological areas.

High incidences of Small Cell Carcinoma & Adenocarcinoma of the lung, Astrocytoma & Glioblastoma Multiforme of the brain and Mesothelioma of the lung were found in those who had a high accumulation of Asbestos in the eyes and upper respiratory system (nose, larynx, trachea, etc.). When measured non-invasively using the Bi-Digital O-Ring Test (BDORT), brain tumors had the highest concentration of Asbestos (0.2 approximately 2.1 mg BDORT units). Relatively high levels of Asbestos (0.2 approximately 0.6 mg BDORT units) were found in: Squamous Cell Carcinoma of the lungs & esophagus, Adenocarcinoma of the larynx & breast, myelogenic leukemia, arteries of these cancers, left ventricle of failing heart, myocardial infarction, some of the narrowed arteries, varicose veins, cataracts, balding heads, hot flashes, Alzheimer's Disease and Autism. A small, round or ellipsoidal area, with diameter of 5 mm or less, was found near the center of every cancer tissue with a higher level of Asbestos (1 approximately 3 mg), As, Zn, Cr and Se, than in the rest of the tumor; this small area may be where the cancer initiated. Among areas of intractable pain with frequent recurrence and gradual worsening, about 0.2 approximately 0.5 mg BDORT units (or higher) of Asbestos were found. The author found that in the Astrocytoma and many other cancer patients, the optimal dose of DHEA produced very significant reductions of cancer cell telomere from over 1400 ng in the brain tumors (and over 900 ng in other cancers) to close to or less than 1 yg (=10(-24) g), with circulatory improvement by reduction of TXB2. Unlike the standard, widely used treatment with DHEA 25 approximately 50 mg daily, which is an overdose; we only gave one optimal dose (1.5 approximately 12.5 mg) and the beneficial effects usually lasted anywhere between 3-6 months, unless inhibiting factors were introduced. In addition, once one optimal dose of DHEA was given, the amount of Asbestos from these tumors decreased very significantly (30 approximately 99% reduction) with marked increase in urine Asbestos. One optimal dose of special Cilantro tablet reduced more Asbestos than DHEA or (+) Qi Gong Energy Stored Paper. In addition, the application of (+) Solar Energy Stored Paper often reduces 70 approximately 99% of the Asbestos, while (+) Qi Gong Energy Stored Paper reduces 50 approximately 99% of the Asbestos.

Adult↗
PubMed1999

Comment on the use of GOES solar proton data and spectra in solar proton dose calculations.

There is a need to understand the calibration and response of the GOES solar particle detectors since the GOES data are being used to evaluate high energy solar particle events. We share some of our experience in utilizing these data in the analysis of solar particle ground-level events (GLEs). For the 29 September 1989 event, we have evaluated the solar proton and alpha particle spectral characteristics throughout the event. The results show that the solar cosmic ray spectrum is extremely hard at low energies with the magnitude of the slope increasing with increasing energy and with time.

Alpha Particles↗
PubMed2006

Solar photocatalytic degradation of reactive blue 4 using a Fresnel lens.

The heterogeneous photocatalytic degradation of reactive blue 4 dye (RB4) solutions under Fenton reagent and TiO(2) assisted by concentrated solar light irradiation using a Fresnel lens has been studied. Multivariate experimental design was applied to study the kinetic process. The efficiency of photocatalytic degradation was determined from the analysis of color and total organic carbon (TOC) removal. Factorial experimental design allowed to determine the influence of four parameters (pH and initial concentrations of TiO(2), Fe(II) and H(2)O(2)) on the value of the decoloration kinetic rate constant. Experimental data were fitted using neural networks (NNs). The mathematical model reproduces experimental data within 86% of confidence and allows the simulation of the process for any value of parameters in the experimental range studied. Also, a measure of the saliency of the input variables was made based upon the connection weights of the neural networks, allowing the analysis of the relative relevance of each variable with respect to the others. Results showed that acidic pHs (pH=3.6) are preferred for the complete dye decoloration. The optimum catalyst concentration is 1.2g TiO(2)/l. The use of a low cost catalyst and its activation using a Fresnel lens to concentrate solar energy significantly accelerates the degradation process when compared with direct solar radiation alone and can offer an economical and practical alternative for the destruction of environmental organic compounds.

Hydrogen Peroxide↗