Journal articles: 'Solar cells, Extraterrestrial environments'

1

Iles, Peter A. "Future use of silicon solar cells in extraterrestrial applications." Progress in Photovoltaics: Research and Applications 2, no. 2 (April 1994): 95–106. http://dx.doi.org/10.1002/pip.4670020204.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Lage, Claudia A. S., Gabriel Z. L. Dalmaso, Lia C. R. S. Teixeira, Amanda G. Bendia, Ivan G. Paulino-Lima, Douglas Galante, Eduardo Janot-Pacheco, et al. "Mini-Review: Probing the limits of extremophilic life in extraterrestrial environment-simulated experiments." International Journal of Astrobiology 11, no. 4 (August 16, 2012): 251–56. http://dx.doi.org/10.1017/s1473550412000316.

Full text

Abstract:

AbstractAstrobiology is a relatively recent scientific field that seeks to understand the origin and dynamics of life in the Universe. Several hypotheses have been proposed to explain life in the cosmic context throughout human history, but only now, technology has allowed many of them to be tested. Laboratory experiments have been able to show how chemical elements essential to life, such as carbon, nitrogen, oxygen and hydrogen combine in biologically important compounds. Interestingly, these compounds are ubiquitous. How these compounds were combined to the point of originating cells and complex organisms is still to be unveiled by science. However, our 4.5 billion years old Solar system appeared in a 10 billion years old Universe. Thus, simple cells such as micro-organisms may have had time to form in planets older than ours or in other suitable places in the Universe. One hypothesis related to the appearance of life on Earth is called panspermia, which predicts that microbial life could have been formed in the Universe billions of years ago, travelling between planets, and inseminating units of life that could have become more complex in habitable planets such as Earth. A project designed to test the viability of extremophile micro-organisms exposed to simulated extraterrestrial environments is in progress at the Carlos Chagas Filho Institute of Biophysics (UFRJ, Brazil) to test whether microbial life could withstand inhospitable environments. Radiation-resistant (known or novel ones) micro-organisms collected from extreme terrestrial environments have been exposed (at synchrotron accelerators) to intense radiation sources simulating Solar radiation, capable of emitting radiation in a few hours equivalent to many years of accumulated doses. The results obtained in these experiments reveal an interesting possibility of the existence of microbial life beyond Earth.

APA, Harvard, Vancouver, ISO, and other styles

3

Guttenberg, Nicholas, Huan Chen, Tomohiro Mochizuki, and H. Cleaves. "Classification of the Biogenicity of Complex Organic Mixtures for the Detection of Extraterrestrial Life." Life 11, no. 3 (March 12, 2021): 234. http://dx.doi.org/10.3390/life11030234.

Full text

Abstract:

Searching for life in the Universe depends on unambiguously distinguishing biological features from background signals, which could take the form of chemical, morphological, or spectral signatures. The discovery and direct measurement of organic compounds unambiguously indicative of extraterrestrial (ET) life is a major goal of Solar System exploration. Biology processes matter and energy differently from abiological systems, and materials produced by biological systems may become enriched in planetary environments where biology is operative. However, ET biology might be composed of different components than terrestrial life. As ET sample return is difficult, in situ methods for identifying biology will be useful. Mass spectrometry (MS) is a potentially versatile life detection technique, which will be used to analyze numerous Solar System environments in the near future. We show here that simple algorithmic analysis of MS data from abiotic synthesis (natural and synthetic), microbial cells, and thermally processed biological materials (lab-grown organisms and petroleum) easily identifies relational organic compound distributions that distinguish pristine and aged biological and abiological materials, which likely can be attributed to the types of compounds these processes produce, as well as how they are formed and decompose. This method is independent of the detection of particular masses or molecular species samples may contain. This suggests a general method to agnostically detect evidence of biology using MS given a sufficiently strong signal in which the majority of the material in a sample has either a biological or abiological origin. Such metrics are also likely to be useful for studies of possible emergent living phenomena, and paleobiological samples.

APA, Harvard, Vancouver, ISO, and other styles

4

Abrevaya, Ximena C., Eduardo Cortón, and Pablo J. D. Mauas. "UV habitability and dM stars: an approach for evaluation of biological survival." Proceedings of the International Astronomical Union 5, S264 (August 2009): 443–45. http://dx.doi.org/10.1017/s1743921309993073.

Full text

Abstract:

AbstractDwarf M stars comprise about 75 percent of all stars in the galaxy. For several years planets orbiting M stars have been discarded as suitable places for development of life. This paradigm now has changed and terrestrial-type planets within liquid-water habitable zones (LW-HZ) around M stars are reconsidered as possible hosts for life as we know it. Nevertheless, large amount of UV radiation is emitted during flares by this stars, and it is uncertain how these events could affect biological systems. In particular UV-C λ < 290nm) exhibits the most damaging effects for living organisms. To analyze the hypothesis that UV could set a limit for the development of extraterrestrial life, we studied the effect of UV-C treatment on halophile archaea cultures. Halophile archaea are extremophile organisms, they are exposed to intense solar UV radiation in their natural environment so they are generally regarded as relatively UV tolerant. Halophiles inhabits in hipersaline environments as salt lakes but also have been found in ancient salt deposits as halites and evaporites on Earth. Since evaporites have been detected in Martian meteorites, these organisms are proposed as plausible inhabitants of Mars-like planets. Our preliminary results show that even after UV damage, the surviving cells were able to resume growth with nearly normal kinetics.

APA, Harvard, Vancouver, ISO, and other styles

5

Horneck, Gerda, David M. Klaus, and Rocco L. Mancinelli. "Space Microbiology." Microbiology and Molecular Biology Reviews 74, no. 1 (March 2010): 121–56. http://dx.doi.org/10.1128/mmbr.00016-09.

Full text

Abstract:

SUMMARY The responses of microorganisms (viruses, bacterial cells, bacterial and fungal spores, and lichens) to selected factors of space (microgravity, galactic cosmic radiation, solar UV radiation, and space vacuum) were determined in space and laboratory simulation experiments. In general, microorganisms tend to thrive in the space flight environment in terms of enhanced growth parameters and a demonstrated ability to proliferate in the presence of normally inhibitory levels of antibiotics. The mechanisms responsible for the observed biological responses, however, are not yet fully understood. A hypothesized interaction of microgravity with radiation-induced DNA repair processes was experimentally refuted. The survival of microorganisms in outer space was investigated to tackle questions on the upper boundary of the biosphere and on the likelihood of interplanetary transport of microorganisms. It was found that extraterrestrial solar UV radiation was the most deleterious factor of space. Among all organisms tested, only lichens (Rhizocarpon geographicum and Xanthoria elegans) maintained full viability after 2 weeks in outer space, whereas all other test systems were inactivated by orders of magnitude. Using optical filters and spores of Bacillus subtilis as a biological UV dosimeter, it was found that the current ozone layer reduces the biological effectiveness of solar UV by 3 orders of magnitude. If shielded against solar UV, spores of B. subtilis were capable of surviving in space for up to 6 years, especially if embedded in clay or meteorite powder (artificial meteorites). The data support the likelihood of interplanetary transfer of microorganisms within meteorites, the so-called lithopanspermia hypothesis.

APA, Harvard, Vancouver, ISO, and other styles

6

Ehrenfreund, Pascale, Andreas Elsaesser, and J. Groen. "Prebiotic Matter in Space." Proceedings of the International Astronomical Union 10, H16 (August 2012): 709–10. http://dx.doi.org/10.1017/s1743921314013015.

Full text

Abstract:

AbstractA significant number of molecules that are used in contemporary biochemistry on Earth are found in interstellar and circumstellar regions as well as solar system environments. In particular small solar system bodies hold clues to processes that formed our solar system. Comets, asteroids, and meteorite delivered extraterrestrial material during the heavy bombardment phase ~3.9 billion years ago to the young planets, a process that made carbonaceous material available to the early Earth. In-depth understanding of the organic reservoir in different space environments as well as data on the stability of organic and prebiotic material in solar system environments are vital to assess and quantify the extraterrestrial contribution of prebiotic sources available to the young Earth.

APA, Harvard, Vancouver, ISO, and other styles

7

McKaig, Jordan, Tristan Caro, Alex Hyer, Elizabeth Delgadillo Talburt, Sonali Verma, Kaixin Cui, Anna-Sophia Boguraev, et al. "A High-Altitude Balloon Platform for Space Life Sciences Education." Gravitational and Space Research 7, no. 1 (November 27, 2019): 62–69. http://dx.doi.org/10.2478/gsr-2019-0007.

Full text

Abstract:

AbstractHigh-altitude balloons (HABs) present a valuable and cost-effective tool for educators and students to access the conditions that are analogous to space and extraterrestrial environments in the Earth’s upper atmosphere. Historically, HABs have been used for meteorological measurements, observation, sampling of aerosols, and exposure of samples to upper atmosphere environments. The Earth’s stratosphere allows researchers access to a unique combination of wideband solar radiation, extreme cold, rarefied air, low humidity, and acute ionizing radiation—conditions that are relevant to space biology research. Here, we describe a reproducible payload for a HAB mission that can be constructed, launched, and retrieved for about $3,000. This general standard operating procedure can be used by educators, community scientists, and research teams working with limited resources.

APA, Harvard, Vancouver, ISO, and other styles

8

Ishii, Hope A., John P. Bradley, Hans A. Bechtel, Donald E. Brownlee, Karen C. Bustillo, James Ciston, Jeffrey N. Cuzzi, Christine Floss, and David J. Joswiak. "Multiple generations of grain aggregation in different environments preceded solar system body formation." Proceedings of the National Academy of Sciences 115, no. 26 (June 11, 2018): 6608–13. http://dx.doi.org/10.1073/pnas.1720167115.

Full text

Abstract:

The solar system formed from interstellar dust and gas in a molecular cloud. Astronomical observations show that typical interstellar dust consists of amorphous (a-) silicate and organic carbon. Bona fide physical samples for laboratory studies would yield unprecedented insight about solar system formation, but they were largely destroyed. The most likely repositories of surviving presolar dust are the least altered extraterrestrial materials, interplanetary dust particles (IDPs) with probable cometary origins. Cometary IDPs contain abundant submicrona-silicate grains called GEMS (glass with embedded metal and sulfides), believed to be carbon-free. Some have detectable isotopically anomalousa-silicate components from other stars, proving they are preserved dust inherited from the interstellar medium. However, it is debated whether the majority of GEMS predate the solar system or formed in the solar nebula by condensation of high-temperature (>1,300 K) gas. Here, we map IDP compositions with single nanometer-scale resolution and find that GEMS contain organic carbon. Mapping reveals two generations of grain aggregation, the key process in growth from dust grains to planetesimals, mediated by carbon. GEMS grains, some witha-silicate subgrains mantled by organic carbon, comprise the earliest generation of aggregates. These aggregates (and other grains) are encapsulated in lower-density organic carbon matrix, indicating a second generation of aggregation. Since this organic carbon thermally decomposes above ∼450 K, GEMS cannot have accreted in the hot solar nebula, and formed, instead, in the cold presolar molecular cloud and/or outer protoplanetary disk. We suggest that GEMS are consistent with surviving interstellar dust, condensed in situ, and cycled through multiple molecular clouds.

APA, Harvard, Vancouver, ISO, and other styles

9

Varnali, Tereza, and Howell G. M. Edwards. "Raman spectroscopic identification of scytonemin and its derivatives as key biomarkers in stressed environments." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2030 (December 13, 2014): 20140197. http://dx.doi.org/10.1098/rsta.2014.0197.

Full text

Abstract:

Raman spectroscopy has been identified as an important first-pass analytical technique for deployment on planetary surfaces as part of a suite of instrumentation in projected remote space exploration missions to detect extant or extinct extraterrestrial life signatures. Aside from the demonstrable advantages of a non-destructive sampling procedure and an ability to record simultaneously the molecular signatures of biological, geobiological and geological components in admixture in the geological record, the interrogation and subsequent interpretation of spectroscopic data from these experiments will be critically dependent upon the recognition of key biomolecular markers indicative of life existing or having once existed in extreme habitats. A comparison made with the characteristic Raman spectral wavenumbers obtained from standards is not acceptable because of shifts that can occur in the presence of other biomolecules and their host mineral matrices. In this paper, we identify the major sources of difficulty experienced in the interpretation of spectroscopic data centring on a key family of biomarker molecules, namely scytonemin and its derivatives; the parent scytonemin has been characterized spectroscopically in cyanobacterial colonies inhabiting some of the most extreme terrestrial environments and, with the support of theoretical calculations, spectra have been predicted for the characterization of several of its derivatives which could occur in novel extraterrestrial environments. This work will form the foundation for the identification of novel biomarkers and for their Raman spectroscopic discrimination, an essential step in the interpretation of potentially complex and hitherto unknown biological radiation protectants based on the scytoneman and scytonin molecular skeletons which may exist in niche geological scenarios in the surface and subsurface of planets and their satellites in our Solar System.

APA, Harvard, Vancouver, ISO, and other styles

10

Pavlov, Anatoly, Vladimir Cheptsov, Denis Tsurkov, Vladimir Lomasov, Dmitry Frolov, and Gennady Vasiliev. "Survival of Radioresistant Bacteria on Europa’s Surface after Pulse Ejection of Subsurface Ocean Water." Geosciences 9, no. 1 (December 25, 2018): 9. http://dx.doi.org/10.3390/geosciences9010009.

Full text

Abstract:

We briefly present preliminary results of our study of the radioresistant bacteria in a low temperature and pressure and high-radiation environment and hypothesize the ability of microorganisms to survive extraterrestrial high-radiation environments, such as the icy surface of Jupiter’s moon, Europa. In this study, samples containing a strain of Deinococcus radiodurans VKM B-1422T embedded into a simulated version of Europa’s ice were put under extreme environmental (−130 °C, 0.01 mbar) and radiation conditions using a specially designed experimental vacuum chamber. The samples were irradiated with 5, 10, 50, and 100 kGy doses and subsequently studied for residual viable cells. We estimate the limit of the accumulated dose that viable cells in those conditions could withstand at 50 kGy. Combining our numerical modelling of the accumulated dose in ice with observations of water eruption events on Europa, we hypothesize that in the case of such events, it is possible that putative extraterrestrial organisms might retain viability in a dormant state for up to 10,000 years, and could be sampled and studied by future probe missions.

APA, Harvard, Vancouver, ISO, and other styles

11

Higgins, P. M., and C. S. Cockell. "A bioenergetic model to predict habitability, biomass and biosignatures in astrobiology and extreme conditions." Journal of The Royal Society Interface 17, no. 171 (October 2020): 20200588. http://dx.doi.org/10.1098/rsif.2020.0588.

Full text

Abstract:

In order to grow, reproduce and evolve life requires a supply of energy and nutrients. Astrobiology has the challenge of studying life on Earth in environments which are poorly characterized or extreme, usually both, and predicting the habitability of extraterrestrial environments. We have developed a general astrobiological model for assessing the energetic and nutrient availability of poorly characterized environments to predict their potential biological productivity. NutMEG (nutrients, maintenance, energy and growth) can be used to estimate how much biomass an environment could host, and how that life might affect the local chemistry. It requires only an overall catabolic reaction and some knowledge of the local environment to begin making estimations, with many more customizable parameters, such as microbial adaptation. In this study, the model was configured to replicate laboratory data on the growth of methanogens. It was used to predict the effect of temperature and energy/nutrient limitation on their microbial growth rates, total biomass levels, and total biosignature production in laboratory-like conditions to explore how it could be applied to astrobiological problems. As temperature rises from 280 to 330 K, NutMEG predicts exponential drops in final biomass ( 10 9 − 10 6 cells l − 1 ) and total methane production ( 62 − 3 μ M ) despite an increase in peak growth rates ( 0.007 − 0.14 h − 1 ) for a typical methanogen in ideal conditions. This is caused by the increasing cost of microbial maintenance diverting energy away from growth processes. Restricting energy and nutrients exacerbates this trend. With minimal assumptions NutMEG can reliably replicate microbial growth behaviour, but better understanding of the synthesis and maintenance costs life must overcome in different extremes is required to improve its results further. NutMEG can help us assess the theoretical habitability of extraterrestrial environments and predict potential biomass and biosignature production, for example on exoplanets using minimum input parameters to guide observations.

APA, Harvard, Vancouver, ISO, and other styles

12

Wang, Xiaohui, Hojjatollah Sarvari, Hongmei Dang, Zhi Chen, and Vijay Singh. "Evolution characteristics of perovskite solar cells in air and vacuum environments." Optik 150 (December 2017): 111–16. http://dx.doi.org/10.1016/j.ijleo.2017.09.100.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Rietmeijer, Frans J. M. "Microbeam Analyses of the Most Challenging Extraterrestrial Samples Ever Returned." Microscopy Today 15, no. 4 (July 2007): 6–11. http://dx.doi.org/10.1017/s1551929500055656.

Full text

Abstract:

This mission flew by Comet 81P/Wild 2 where it collected more than 10,000 particles, ranging from tens of nanometers to hundreds of microns, and carried them to Earth for a safe landing in the Utah desert on January 15, 2006. So what? The answer depends on one's interest. Technically, it was a perfect DISCOVERY-class mission from launch to soft-landing (Figure 1). Scientifically, it delivered some of the 4.6 Gyrsold particles that went into making the planets of our solar system and for the first time ever we have samples from a known comet.Many challenges lie ahead. First, the grains must be extracted from the capture cells, and prepared for mineralogical and chemical analyses, including stable isotopes and organic phases. Second, the NASA/JSC Stardust Curatorial Facility has to prepare and keep track of each sample allocation. Third, data collected in many laboratories around the globe will need to be synchronized for publication.

APA, Harvard, Vancouver, ISO, and other styles

14

Aureli, Lorenzo, Claudia Pacelli, Alessia Cassaro, Akira Fujimori, Ralf Moeller, and Silvano Onofri. "Iron Ion Particle Radiation Resistance of Dried Colonies of Cryomyces antarcticus Embedded in Martian Regolith Analogues." Life 10, no. 12 (November 24, 2020): 306. http://dx.doi.org/10.3390/life10120306.

Full text

Abstract:

Among the celestial bodies in the Solar System, Mars currently represents the main target for the search for life beyond Earth. However, its surface is constantly exposed to high doses of cosmic rays (CRs) that may pose a threat to any biological system. For this reason, investigations into the limits of resistance of life to space relevant radiation is fundamental to speculate on the chance of finding extraterrestrial organisms on Mars. In the present work, as part of the STARLIFE project, the responses of dried colonies of the black fungus Cryomyces antarcticus Culture Collection of Fungi from Extreme Environments (CCFEE) 515 to the exposure to accelerated iron (LET: 200 keV/μm) ions, which mimic part of CRs spectrum, were investigated. Samples were exposed to the iron ions up to 1000 Gy in the presence of Martian regolith analogues. Our results showed an extraordinary resistance of the fungus in terms of survival, recovery of metabolic activity and DNA integrity. These experiments give new insights into the survival probability of possible terrestrial-like life forms on the present or past Martian surface and shallow subsurface environments.

APA, Harvard, Vancouver, ISO, and other styles

15

Matthews, Clifford N. "Universal Protein Ancestors from Hydrogen Cyanide and Water." Symposium - International Astronomical Union 112 (1985): 151–56. http://dx.doi.org/10.1017/s0074180900146467.

Full text

Abstract:

Current research in cosmochemistry shows that crude organic solids of high molecular weight are readily formed in planetary, interplanetary and interstellar environments. What are the components of these intractable materials and how are they connected, if at all, with the beginnings of life? It is proposed here that underlying much of this ubiquitous chemistry is a low energy route leading directly to the synthesis of heteropolypeptides from hydrogen cyanide and water. Evidence from laboratory and extraterrestrial investigations suggests that this hydrogen cyanide polymerization is a truly universal process that accounts not only for the past synthesis of protein ancestors on Earth but also for reactions proceeding elsewhere today within our solar system, on planetary bodies around other stars and in the dusty molecular clouds of spiral galaxies. The existence of this preferred pathway adds greatly to the probability of life being widespread in the universe.

APA, Harvard, Vancouver, ISO, and other styles

16

Minnaert, Ben, and Peter Veelaert. "The Suitability of Organic Solar Cells for Different Indoor Conditions." Advances in Science and Technology 74 (October 2010): 170–75. http://dx.doi.org/10.4028/www.scientific.net/ast.74.170.

Full text

Abstract:

Most commercially available photovoltaic solar cells are crystalline silicon cells. However, in indoor environments, the efficiency of Si-cells is poor. Typically, the light intensity under artificial lighting conditions is less than 10 W/m² as compared to 100-1000 W/m² under outdoor conditions. Moreover, the spectrum is different from the outdoor solar spectrum and there is more diffuse than direct light. Taken into account the predicted cheaper costs for the production of organic solar cells, a possible niche market for organic PV can be indoor applications. In this article, we study the properties and suitability of several bulk heterojunction organic solar cells (with distinct different absorption spectra) for different indoor conditions. We simulate different light environments and use a silicon solar cell as reference. Depending on the required power for the indoor device, we determine minimum requirements for the environment (light intensity and indoor spectrum) and for the organic solar cell (absorption spectrum and surface area). In this way we determine the appropriateness and conditions for a competitive indoor use of organic solar cells.

APA, Harvard, Vancouver, ISO, and other styles

17

Balderrama, V. S., M. Estrada, P. L. Han, P. Granero, J. Pallarés, J. Ferré-Borrull, and L. F. Marsal. "Degradation of electrical properties of PTB1:PCBM solar cells under different environments." Solar Energy Materials and Solar Cells 125 (June 2014): 155–63. http://dx.doi.org/10.1016/j.solmat.2014.02.035.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Elmasry, Walaa, Yoko Kebukawa, and Kensei Kobayashi. "Synthesis of Organic Matter in Aqueous Environments Simulating Small Bodies in the Solar System and the Effects of Minerals on Amino Acid Formation." Life 11, no. 1 (January 6, 2021): 32. http://dx.doi.org/10.3390/life11010032.

Full text

Abstract:

The extraterrestrial delivery of organics to primitive Earth has been supported by many laboratory and space experiments. Minerals played an important role in the evolution of meteoritic organic matter. In this study, we simulated aqueous alteration in small bodies by using a solution mixture of H2CO and NH3 in the presence of water at 150 °C under different heating durations, which produced amino acids after acid hydrolysis. Moreover, minerals were added to the previous mixture to examine their catalyzing/inhibiting impact on amino acid formation. Without minerals, glycine was the dominant amino acid obtained at 1 d of the heating experiment, while alanine and β-alanine increased significantly and became dominant after 3 to 7 d. Minerals enhanced the yield of amino acids at short heating duration (1 d); however, they induced their decomposition at longer heating duration (7 d). Additionally, montmorillonite enhanced amino acid production at 1 d, while olivine and serpentine enhanced production at 3 d. Molecular weight distribution in the whole of the products obtained by gel chromatography showed that minerals enhanced both decomposition and combination of molecules. Our results indicate that minerals affected the formation of amino acids in aqueous environments in small Solar System bodies and that the amino acids could have different response behaviors according to different minerals.

APA, Harvard, Vancouver, ISO, and other styles

19

Jull, J. A. Timothy, Devendra Lal, George S. Burr, Philip A. Bland, Alexander W. R. Bevan, and J. Warren Beck. "Radiocarbon Beyond this World." Radiocarbon 42, no. 1 (2000): 151–72. http://dx.doi.org/10.1017/s003382220005311x.

Full text

Abstract:

In this paper, we review the production of radiocarbon and other radionuclides in extraterrestrial materials. This radioactivity can be produced by the effects of solar and galactic cosmic rays on solid material in space. In addition, direct implantation at the lunar surface of 14C and other radionuclides can occur. The level of 14C and other radionuclides in a meteorite can be used to determine its residence time on the Earth's surface, or “terrestrial age”. 14C provides the best tool for estimating terrestrial ages of meteorites collected in desert environments. Age control allows us to understand the time constraints on processes by which meteorites are weathered, as well as mean storage times. Third, we discuss the use of the difference in 14C/12C ratio of organic material and carbonates produced on other planetary objects and terrestrial material. These differences can be used to assess the importance of distinguishing primary material formed on the parent body from secondary alteration of meteoritic material after it lands on the earth.

APA, Harvard, Vancouver, ISO, and other styles

20

Ciammaruchi, Laura, Chenggong Wang, Yongli Gao, and Ching W. Tang. "Delineation of degradation patterns of C60-based organic solar cells under different environments." Journal of Applied Physics 117, no. 24 (June 28, 2015): 245504. http://dx.doi.org/10.1063/1.4923091.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Radosavljevic, Radovan, and Aleksandra Vasic. "Effects of radiation on solar cells as photovoltaic generators." Nuclear Technology and Radiation Protection 27, no. 1 (2012): 28–32. http://dx.doi.org/10.2298/ntrp1201028r.

Full text

Abstract:

The growing need for obtaining electrical energy through renewable energy sources such as solar energy have lead to significant technological developments in the production of the basic element of PV conversion, the solar cell. Basically, a solar cell is a p-n junction whose characteristics have a great influence on its output parameters, primarily efficiency. Defects and impurities in the basic material, especially if located within the energy gap, may be activated during its lifetime, becoming traps for optically produced electron-hole pairs and, thus, decreasing the output power of the cell. All of the said effects could be induced in many ways over a lifetime of a solar cell and are consistent with the effects that radiation produces in semiconductor devices. The aim of this paper is to investigate changes in the main characteristics of solar cells, such as efficiency, output current and power, due to the exposure of solar systems to different (hostile) radiation environments.

APA, Harvard, Vancouver, ISO, and other styles

22

Calderón, Francisco, Allan Lüders, David Wettergreen, James Teza, and Andrés Guesalaga. "Analysis of High-Efficiency Solar Cells in Mobile Robot Applications." Journal of Solar Energy Engineering 129, no. 3 (December 14, 2006): 343–46. http://dx.doi.org/10.1115/1.2735361.

Full text

Abstract:

This technical brief analyzes the performance of triple-junction solar cells on a mobile robot. Although originally designed for satellite use, it is demonstrated that triple-junction cells are effective in terrestrial applications. This makes them particularly suitable for systems with limited size and mass but high-power requirements such as a mobile robot. A testing station was specially constructed to characterize triple-junction and conventional silicon cell performance in different environments and to compare their effectiveness. Additional field tests were carried out with an autonomous robot in order to check the ability to deliver sufficient power to varying loads. Results show that they surpass conventional technologies with efficiencies higher than 22%, so they can be considered as an alternative technology for power sources onboard of terrestrial mobile robots.

APA, Harvard, Vancouver, ISO, and other styles

23

Nikolić, Dejan, Koviljka Stanković, Ljubinko Timotijević, Zoran Rajović, and Miloš Vujisić. "Comparative Study of Gamma Radiation Effects on Solar Cells, Photodiodes, and Phototransistors." International Journal of Photoenergy 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/843174.

Full text

Abstract:

This paper presents the behavior of various optoelectronic devices after gamma irradiation. A number of PIN photodiodes, phototransistors, and solar panels have been exposed to gamma irradiation. Several types of photodiodes and phototransistors were used in the experiment.I-Vcharacteristics (current dependance on voltage) of these devices have been measured before and after irradiation. The process of annealing has also been observed. A comparative analysis of measurement results has been performed in order to determine the reliability of optoelectronic devices in radiation environments.

APA, Harvard, Vancouver, ISO, and other styles

24

Kelly, Laura C., Charles S. Cockell, and Stephen Summers. "Diverse microbial species survive high ammonia concentrations." International Journal of Astrobiology 11, no. 2 (February 3, 2012): 125–31. http://dx.doi.org/10.1017/s147355041200002x.

Full text

Abstract:

AbstractPlanetary protection regulations are in place to control the contamination of planets and moons with terrestrial micro-organisms in order to avoid jeopardizing future scientific investigations relating to the search for life. One environmental chemical factor of relevance in extraterrestrial environments, specifically in the moons of the outer solar system, is ammonia (NH3). Ammonia is known to be highly toxic to micro-organisms and may disrupt proton motive force, interfere with cellular redox reactions or cause an increase of cell pH. To test the survival potential of terrestrial micro-organisms exposed to such cold, ammonia-rich environments, and to judge whether current planetary protection regulations are sufficient, soil samples were exposed to concentrations of NH3from 5 to 35% (v/v) at −80°C and room temperature for periods up to 11 months. Following exposure to 35% NH3, diverse spore-forming taxa survived, including representatives of theFirmicutes(Bacillus, Sporosarcina, Viridibacillus, Paenibacillus, StaphylococcusandBrevibacillus) andActinobacteria(Streptomyces). Non-spore forming organisms also survived, includingProteobacteria(Pseudomonas) andActinobacteria(Arthrobacter) that are known to have environmentally resistant resting states.Clostridiumspp. were isolated from the exposed soil under anaerobic culture. High NH3was shown to cause a reduction in viability of spores over time, but spore morphology was not visibly altered. In addition to its implications for planetary protection, these data show that a large number of bacteria, potentially including spore-forming pathogens, but also environmentally resistant non-spore-formers, can survive high ammonia concentrations.

APA, Harvard, Vancouver, ISO, and other styles

25

Dyson, Freeman J. "Looking for life in unlikely places: reasons why planets may not be the best places to look for life." International Journal of Astrobiology 2, no. 2 (April 2003): 103–10. http://dx.doi.org/10.1017/s1473550403001538.

Full text

Abstract:

A new method is proposed to search for extraterrestrial life adapted to cold environments far from the Sun. To keep warm, using the light from a distant sun, any life-form must grow a system of optical concentrators, lenses or mirrors, to focus sunlight on to its vital parts. Any light not absorbed, or any heat radiation emitted from the vital parts, will be focused by the optical concentrators into a narrow beam pointing back towards the sun. To search for such life-forms, we should scan the sky with optical and infrared telescopes pointing directly away from the Sun. Any living vegetation will be seen as a bright patch in strong contrast to its dark surroundings, like the eyes of a nocturnal animal caught in the headlights of a car. This method of search may be used either with space-based or with ground-based telescopes. Examples of places where the method would work well are the surfaces of Europa, Trojan asteroids or Kuiper Belt objects. Any life-form that adapted successfully to a vacuum environment would be likely to spread widely over objects with icy surfaces in the outer regions of the solar system.

APA, Harvard, Vancouver, ISO, and other styles

26

Becker-Koch, David, Miguel Albaladejo-Siguan, Vincent Lami, Fabian Paulus, Hengyang Xiang, Zhuoying Chen, and Yana Vaynzof. "Ligand dependent oxidation dictates the performance evolution of high efficiency PbS quantum dot solar cells." Sustainable Energy & Fuels 4, no. 1 (2020): 108–15. http://dx.doi.org/10.1039/c9se00602h.

Full text

Abstract:

The stability of lead sulfide (PbS) quantum dots (QD) under continuous illumination in oxygenated environments depends on the choice of ligands, determining the evolution of photovoltaic performance of high efficiency PbS QD solar cells.

APA, Harvard, Vancouver, ISO, and other styles

27

Doc Richardson, C., Nancy W. Hinman, and Jill R. Scott. "Effect of thenardite on the direct detection of aromatic amino acids: implications for the search for life in the solar system." International Journal of Astrobiology 8, no. 4 (August 28, 2009): 291–300. http://dx.doi.org/10.1017/s1473550409990231.

Full text

Abstract:

AbstractWith the discovery of Na-sulphate minerals on Mars and Europa, recent studies using these minerals have focused on their ability to assist in the detection of bio/organic signatures. This study further investigates the ability of thenardite (Na2SO4) to effectively facilitate the ionization and identification of aromatic amino acids (phenylalanine, tyrosine and tryptophan) using a technique called geomatrix-assisted laser desorption/ionization in conjunction with a Fourier transform ion cyclotron resonance mass spectrometry. This technique is based on the ability of a mineral host to facilitate desorption and ionization of bio/organic molecules for detection. Spectra obtained from each aromatic amino acid alone and in combination with thenardite show differences in ionization mechanism and fragmentation patterns. These differences are due to chemical and structural differences between the aromatic side chains of their respective amino acid. Tyrosine and tryptophan when combined with thenardite were observed to undergo cation-attachment ([M+Na]+), due to the high alkali ion affinity of their aromatic side chains. In addition, substitution of the carboxyl group hydrogen by sodium led to formation of [M-H+Na]Na+ peaks. In contrast, phenylalanine mixed with thenardite showed no evidence of Na+ attachment. Understanding how co-deposition of amino acids with thenardite can affect the observed mass spectra is important for future exploration missions that are likely to use laser desorption mass spectrometry to search for bio/organic compounds in extraterrestrial environments.

APA, Harvard, Vancouver, ISO, and other styles

28

Hu, Jisong, Xinguo Ma, Wangyang Duan, Zhifeng Liu, Ting Liu, Hui Lv, Chuyun Huang, Ling Miao, and Jianjun Jiang. "First-Principles Calculations of Graphene-Coated CH3NH3PbI3 toward Stable Perovskite Solar Cells in Humid Environments." ACS Applied Nano Materials 3, no. 8 (July 21, 2020): 7704–12. http://dx.doi.org/10.1021/acsanm.0c01301.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

La Duc, Myron T., Anne Dekas, Shariff Osman, Christine Moissl, David Newcombe, and Kasthuri Venkateswaran. "Isolation and Characterization of Bacteria Capable of Tolerating the Extreme Conditions of Clean Room Environments." Applied and Environmental Microbiology 73, no. 8 (February 16, 2007): 2600–2611. http://dx.doi.org/10.1128/aem.03007-06.

Full text

Abstract:

ABSTRACT In assessing the bacterial populations present in spacecraft assembly, spacecraft test, and launch preparation facilities, extremophilic bacteria (requiring severe conditions for growth) and extremotolerant bacteria (tolerant to extreme conditions) were isolated. Several cultivation approaches were employed to select for and identify bacteria that not only survive the nutrient-limiting conditions of clean room environments but can also withstand even more inhospitable environmental stresses. Due to their proximity to spacefaring objects, these bacteria pose a considerable risk for forward contamination of extraterrestrial sites. Samples collected from four geographically distinct National Aeronautics and Space Administration clean rooms were challenged with UV-C irradiation, 5% hydrogen peroxide, heat shock, pH extremes (pH 3.0 and 11.0), temperature extremes (4°C to 65°C), and hypersalinity (25% NaCl) prior to and/or during cultivation as a means of selecting for extremotolerant bacteria. Culture-independent approaches were employed to measure viable microbial (ATP-based) and total bacterial (quantitative PCR-based) burdens. Intracellular ATP concentrations suggested a viable microbial presence ranging from below detection limits to 106 cells/m2. However, only 0.1 to 55% of these viable cells were able to grow on defined culture medium. Isolated members of the Bacillaceae family were more physiologically diverse than those reported in previous studies, including thermophiles (Geobacillus), obligate anaerobes (Paenibacillus), and halotolerant, alkalophilic species (Oceanobacillus and Exiguobacterium). Non-spore-forming microbes (α- and β-proteobacteria and actinobacteria) exhibiting tolerance to the selected stresses were also encountered. The multiassay cultivation approach employed herein enhances the current understanding of the physiological diversity of bacteria housed in these clean rooms and leads us to ponder the origin and means of translocation of thermophiles, anaerobes, and halotolerant alkalophiles into these environments.

APA, Harvard, Vancouver, ISO, and other styles

30

Stojanovic, Nebojsa, Biljana Simic, Koviljka Stankovic, and Djordje Lazarevic. "Degradation effects of the output electrical characteristics of Si solar cells as a result of ionizing radiation under low light conditions." Nuclear Technology and Radiation Protection 30, no. 3 (2015): 210–13. http://dx.doi.org/10.2298/ntrp1503210s.

Full text

Abstract:

This paper presents results of radiation resistance of different types of commercially available single- and poly-crystalline silicon solar cells. Sample cells were subjected to gamma radiation from gamma radiation source 60Co. Characteristic parameters of solar cells were extracted from obtained I-V curves: open circuit voltage, short circuit current, maximum power point voltage and current, efficiency, fill factor, and series resistance. Obtained results show the level of parameters' degradation with purpose of increasing solar cells applications in radiation environments.

APA, Harvard, Vancouver, ISO, and other styles

31

Watson, Jonathan S., Victoria K. Pearson, Mark A. Sephton, and Iain Gilmour. "Molecular, isotopic and in situ analytical approaches to the study of meteoritic organic material." International Journal of Astrobiology 3, no. 2 (April 2004): 107–16. http://dx.doi.org/10.1017/s1473550404002046.

Full text

Abstract:

Organic materials isolated from carbonaceous meteorites provide us with a record of pre-biotic chemistry in the early Solar System. Molecular, isotopic and in situ studies of these materials suggest that a number of extraterrestrial environments have contributed to the inventory of organic matter in the early Solar System including interstellar space, the Solar nebula and meteorite parent bodies.There are several difficulties that have to be overcome in the study of the organic constituents of meteorites. Contamination by terrestrial biogenic organic matter is an ever-present concern and a wide variety of contaminant molecules have been isolated and identified including essential plant oils, derived from either biological sources or common cleaning products, and aliphatic hydrocarbons, most probably derived from petroleum-derived pollutants. Only 25% of the organic matter in carbonaceous chondrites is amenable to extraction with organic solvents; the remainder is present as a complex macromolecular aromatic network that has required the development of analytical approaches that can yield structural and isotopic information on this highly complex material.Stable isotopic studies have been of paramount importance in understanding the origins of meteoritic organic matter and have provided evidence for the incorporation of interstellar molecules within meteoritic material. Extending isotopic studies to the molecular level is yielding new insights into both the sources of meteoritic organic matter and the processes that have modified it.Organic matter in meteorites is intimately associated with silicate minerals and the in situ examination of the relationships between organic and inorganic components is crucial to our understanding of the role of asteroidal processes in the modification of organic matter and, in particular, the role of water as both a solvent and a reactant on meteorite parent bodies.

APA, Harvard, Vancouver, ISO, and other styles

32

Aristidou, Nick, Christopher Eames, M. Saiful Islam, and Saif A. Haque. "Insights into the increased degradation rate of CH3NH3PbI3 solar cells in combined water and O2 environments." Journal of Materials Chemistry A 5, no. 48 (2017): 25469–75. http://dx.doi.org/10.1039/c7ta06841g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Tjoa, J. N. K. Y., M. Mueller, and F. F. S. van der Tak. "The subsurface habitability of small, icy exomoons." Astronomy & Astrophysics 636 (April 2020): A50. http://dx.doi.org/10.1051/0004-6361/201937035.

Full text

Abstract:

Context. Assuming our Solar System as typical, exomoons may outnumber exoplanets. If their habitability fraction is similar, they would thus constitute the largest portion of habitable real estate in the Universe. Icy moons in our Solar System, such as Europa and Enceladus, have already been shown to possess liquid water, a prerequisite for life on Earth. Aims. We intend to investigate under what thermal and orbital circumstances small, icy moons may sustain subsurface oceans and thus be “subsurface habitable”. We pay specific attention to tidal heating, which may keep a moon liquid far beyond the conservative habitable zone. Methods. We made use of a phenomenological approach to tidal heating. We computed the orbit averaged flux from both stellar and planetary (both thermal and reflected stellar) illumination. We then calculated subsurface temperatures depending on illumination and thermal conduction to the surface through the ice shell and an insulating layer of regolith. We adopted a conduction only model, ignoring volcanism and ice shell convection as an outlet for internal heat. In doing so, we determined at which depth, if any, ice melts and a subsurface ocean forms. Results. We find an analytical expression between the moon’s physical and orbital characteristics and the melting depth. Since this expression directly relates icy moon observables to the melting depth, it allows us to swiftly put an upper limit on the melting depth for any given moon. We reproduce the existence of Enceladus’ subsurface ocean; we also find that the two largest moons of Uranus (Titania and Oberon) could well sustain them. Our model predicts that Rhea does not have liquid water. Conclusions. Habitable exomoon environments may be found across an exoplanetary system, largely irrespective of the distance to the host star. Small, icy subsurface habitable moons may exist anywhere beyond the snow line. This may, in future observations, expand the search area for extraterrestrial habitable environments beyond the circumstellar habitable zone.

APA, Harvard, Vancouver, ISO, and other styles

34

Peeters, Z., R. Quinn, Z. Martins, M. A. Sephton, L. Becker, M. C. M. van Loosdrecht, J. Brucato, F. Grunthaner, and P. Ehrenfreund. "Habitability on planetary surfaces: interdisciplinary preparation phase for future Mars missions." International Journal of Astrobiology 8, no. 4 (July 30, 2009): 301–15. http://dx.doi.org/10.1017/s1473550409990140.

Full text

Abstract:

AbstractLife on Earth is one of the outcomes of the formation and evolution of our solar system and has adapted to every explored environment on planet Earth. Recent discoveries have shown that life can exist in extreme environments, such as hydrothermal vents, in deserts and in ice lakes in Antarctica. These findings challenge the definition of the ‘planetary habitable zone’. The objective of future international planetary exploration programmes is to implement a long-term plan for the robotic and human exploration of solar system bodies. Mars has been a central object of interest in the context of extraterrestrial life. The search for extinct or extant life on Mars is one of the main goals of space missions to the Red Planet during the next decade. In this paper we describe the investigation of the physical and chemical properties of Mars soil analogues collected in arid deserts. We measure the pH, redox potential and ion concentrations, as well as carbon and amino acid abundances of soils collected from the Atacama desert (Chile and Peru) and the Salten Skov sediment from Denmark. The samples show large differences in their measured properties, even when taken only several meters apart. A desert sample and the Salten Skov sediment were exposed to a simulated Mars environment to test the stability of amino acids in the soils. The presented laboratory and field studies provide limits to exobiological models, evidence on the effects of subsurface mineral matrices, support current and planned space missions and address planetary protection issues.

APA, Harvard, Vancouver, ISO, and other styles

35

Junghänel, Matthias, and Helmut Tributsch. "Role of Nanochemical Environments in Porous TiO2in Photocurrent Efficiency and Degradation in Dye Sensitized Solar Cells." Journal of Physical Chemistry B 109, no. 48 (December 2005): 22876–83. http://dx.doi.org/10.1021/jp054445r.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Dhakal, Sandeep, Yogesh Gautam, and Aayush Bhattarai. "Evaluation of Temperature-Based Empirical Models and Machine Learning Techniques to Estimate Daily Global Solar Radiation at Biratnagar Airport, Nepal." Advances in Meteorology 2020 (September 16, 2020): 1–11. http://dx.doi.org/10.1155/2020/8895311.

Full text

Abstract:

Global solar radiation (GSR) is a critical variable for designing photovoltaic cells, solar furnaces, solar collectors, and other passive solar applications. In Nepal, the high initial cost and subsequent maintenance cost required for the instrument to measure GSR have restricted its applicability all over the country. The current study compares six different temperature-based empirical models, artificial neural network (ANN), and other five different machine learning (ML) models for estimating daily GSR utilizing readily available meteorological data at Biratnagar Airport. Amongst the temperature-based models, the model developed by Fan et al. performs better than the rest with an R2 of 0.7498 and RMSE of 2.0162 MJm−2d−1. Feed-forward multilayer perceptron (MLP) is utilized to model daily GSR utilizing extraterrestrial solar radiation, sunshine duration, maximum and minimum ambient temperature, precipitation, and relative humidity as inputs. ANN3 performs better than other ANN models with an R2 of 0.8446 and RMSE of 1.4595 MJm−2d−1. Likewise, stepwise linear regression performs better than other ML models with an R2 of 0.8870 and RMSE of 1.5143 MJm−2d−1. Thus, the model developed by Fan et al. is recommended to estimate daily GSR in the region where only ambient temperature data are available. Similarly, a more robust ANN3 and stepwise linear regression models are recommended to estimate daily GSR in the region where data about sunshine duration, maximum and minimum ambient temperature, precipitation, and relative humidity are available.

APA, Harvard, Vancouver, ISO, and other styles

37

Clarke, Declan, and Rodrigo Breguel. "Analysis of Thermodynamic Properties of Cu(In,Ga)Se2 Thin-Film Solar Cells for Viable Space Application." PAM Review Energy Science & Technology 5 (May 31, 2018): 131–49. http://dx.doi.org/10.5130/pamr.v5i0.1501.

Full text

Abstract:

The use of thin film solar cells for power generation when colonizing space stations is an interesting idea. Resisting harsh space environments and low power to mass ratio shows potential for the future application of thin film solar cell in future space application such as roll able solar blankets. Cu(In,Ga)Se2 thin film solar cell are analyzed to determine their viability in space focusing on two modular aspects of emissivity and buffer lays. Findings and calculations showed how temperature affects the efficiency of solar cells and it could also be found how increasing their emissivity with different kinds of coatings can offset the loss in efficiency. Through the study of buffers, it was found that lower band gaps reduce the quantum efficiency of a solar cell. Therefore, ZnS with an energy band gap of 3.5eV will have the least amount of spectral absorption of higher wavelengths.

APA, Harvard, Vancouver, ISO, and other styles

38

Simić, Biljana, Dejan Nikolić, Koviljka Stanković, Ljubinko Timotijević, and Srboljub Stanković. "Damage Induced by Neutron Radiation on Output Characteristics of Solar Cells, Photodiodes, and Phototransistors." International Journal of Photoenergy 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/582819.

Full text

Abstract:

This study investigates the effects of neutron radiation onI-Vcharacteristics (current dependance on voltage) of commercial optoelectronic devices (silicon photodiodes, phototransistors, and solar panels). Current-voltage characteristics of the samples were measured at room temperature before and after irradiation. The diodes were irradiated using Am-Be neutron source with neutron emission of2.7×106 n/s. The results showed a decrease in photocurrent for all samples which could be due to the existence of neutron-induced displacement defects introduced into the semiconductor lattice. The process of annealing has also been observed. A comparative analysis of measurement results has been performed in order to determine the reliability of optoelectronic devices in radiation environments.

APA, Harvard, Vancouver, ISO, and other styles

39

Liu, Yu-Chieh, Hsien-Hsin Chou, Feng-Yi Ho, Hsiang-Jung Wei, Tzu-Chien Wei, and Chen-Yu Yeh. "A feasible scalable porphyrin dye for dye-sensitized solar cells under one sun and dim light environments." Journal of Materials Chemistry A 4, no. 30 (2016): 11878–87. http://dx.doi.org/10.1039/c6ta04097g.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Kim, Ji Hoon, Kook Joo Moon, Jong Man Kim, Dongyun Lee, and Soo Hyung Kim. "Effects of various light-intensity and temperature environments on the photovoltaic performance of dye-sensitized solar cells." Solar Energy 113 (March 2015): 251–57. http://dx.doi.org/10.1016/j.solener.2015.01.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Wei, Zhanhua, Xiaoli Zheng, Haining Chen, Xia Long, Zilong Wang, and Shihe Yang. "A multifunctional C + epoxy/Ag-paint cathode enables efficient and stable operation of perovskite solar cells in watery environments." Journal of Materials Chemistry A 3, no. 32 (2015): 16430–34. http://dx.doi.org/10.1039/c5ta03802b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Osman, Shariff, Zan Peeters, Myron T. La Duc, Rocco Mancinelli, Pascale Ehrenfreund, and Kasthuri Venkateswaran. "Effect of Shadowing on Survival of Bacteria under Conditions Simulating the Martian Atmosphere and UV Radiation." Applied and Environmental Microbiology 74, no. 4 (December 14, 2007): 959–70. http://dx.doi.org/10.1128/aem.01973-07.

Full text

Abstract:

ABSTRACT Spacecraft-associated spores and four non-spore-forming bacterial isolates were prepared in Atacama Desert soil suspensions and tested both in solution and in a desiccated state to elucidate the shadowing effect of soil particulates on bacterial survival under simulated Martian atmospheric and UV irradiation conditions. All non-spore-forming cells that were prepared in nutrient-depleted, 0.2-μm-filtered desert soil (DSE) microcosms and desiccated for 75 days on aluminum died, whereas cells prepared similarly in 60-μm-filtered desert soil (DS) microcosms survived such conditions. Among the bacterial cells tested, Microbacterium schleiferi and Arthrobacter sp. exhibited elevated resistance to 254-nm UV irradiation (low-pressure Hg lamp), and their survival indices were comparable to those of DS- and DSE-associated Bacillus pumilus spores. Desiccated DSE-associated spores survived exposure to full Martian UV irradiation (200 to 400 nm) for 5 min and were only slightly affected by Martian atmospheric conditions in the absence of UV irradiation. Although prolonged UV irradiation (5 min to 12 h) killed substantial portions of the spores in DSE microcosms (∼5- to 6-log reduction with Martian UV irradiation), dramatic survival of spores was apparent in DS-spore microcosms. The survival of soil-associated wild-type spores under Martian conditions could have repercussions for forward contamination of extraterrestrial environments, especially Mars.

APA, Harvard, Vancouver, ISO, and other styles

43

Kim, Soyeon, Muhammad Jahandar, Jae Hoon Jeong, and Dong Chan Lim. "Recent Progress in Solar Cell Technology for Low-Light Indoor Applications." Current Alternative Energy 3, no. 1 (November 28, 2019): 3–17. http://dx.doi.org/10.2174/1570180816666190112141857.

Full text

Abstract:

Photovoltaic cells have recently attracted considerable attention for indoor energy harvesting for low-power-consumption electronic products due to the rapid growth of the Internet of Things (IoT). The IoT platform is being developed with a vision of connecting a variety of wireless electronic devices, such as sensors, household products, and personal data storage devices, which will be able to sense and communicate with their internal states or the external environment. A self-sustainable power source is required to power such devices under low light indoor environments. Inorganic photovoltaic cells show excellent device performance under 1 Sun illumination and dominate the market for outdoor applications. However, their performance is limited for indoor applications with low incident light intensities as they exhibit low photo-voltage. Among the emerging photovoltaic technologies, organic photovoltaics have unique advantages, including solution processibility, flexibility, and lightweight tailorable design; hence, they are considered the best solution for indoor light harvesting applications due to their high photo-voltage, strong absorption of UV-visible wavelengths, and a spectral response similar to that emitted by modern indoor lighting systems. In this review article, we discuss the factors affecting device performance of different photovoltaic technologies under low incident light intensities or indoor conditions and provide a comprehensive analysis of future opportunities for enhancing indoor performance of the photovoltaic devices. Furthermore, we discuss some of the results of semi-transparent organic solar cell which operated under complex environmental conditions like low illumination, incident light angle etc. Based on the results, one can suggest that semi-transparent organic solar cell is a more suitable case for progressive indoor solar cell. After highlighting the factors that limit indoor device performance of photovoltaic cells, we discuss potential applications of IoT devices powered by organic photovoltaic cells in indoor lighting environments.

APA, Harvard, Vancouver, ISO, and other styles

44

Peddapuram, Adithya, Hammad Cheema, Louis McNamara, Yanbing Zhang, Nathan Hammer, and Jared Delcamp. "Quinoxaline-Based Dual Donor, Dual Acceptor Organic Dyes for Dye-Sensitized Solar Cells." Applied Sciences 8, no. 9 (August 21, 2018): 1421. http://dx.doi.org/10.3390/app8091421.

Full text

Abstract:

A novel metal-free quinoxaline-based molecular framework with a dual donor and dual acceptor (DD-π-AA) motif has been introduced. Four sensitizers (AP6, AP8, AP9, and AP12) have been synthesized and fully characterized via UV–Vis absorption, cyclic voltammetry, density functional theory (DFT) calculations, time-correlated single photon counting (TCSPC), and in dye-sensitized solar cell (DSC) devices. Structural modifications to both the donor and acceptor/anchor regions were evaluated via structure–property relationships without altering the quinoxaline π-bridge. Through careful dye design, a broadly absorbing near-infrared (NIR) sensitizer extending electricity production to 800 nm is realized in DSC devices. Ground- and excited-state oxidation potentials were measured to show energetically favorable charge transfer events. Importantly, the dye structure was found to have a strong influence on dye energetics in different environments with structural elements allowing for either similar or dramatically different solution versus film measurements. The DSC device electrolyte was also found to have a significant influence on dye energetics as well. Electron transfer events were probed for each dye with DSC device measurements and with TCSPC studies. The results are correlated to the dye structures.

APA, Harvard, Vancouver, ISO, and other styles

45

Preston, Louisa J., and Lewis R. Dartnell. "Planetary habitability: lessons learned from terrestrial analogues." International Journal of Astrobiology 13, no. 1 (January 2014): 81–98. http://dx.doi.org/10.1017/s1473550413000396.

Full text

Abstract:

AbstractTerrestrial analogue studies underpin almost all planetary missions and their use is essential in the exploration of our Solar system and in assessing the habitability of other worlds. Their value relies on the similarity of the analogue to its target, either in terms of their mineralogical or geochemical context, or current physical or chemical environmental conditions. Such analogue sites offer critical ground-truthing for astrobiological studies on the habitability of different environmental parameter sets, the biological mechanisms for survival in extreme environments and the preservation potential and detectability of biosignatures. The 33 analogue sites discussed in this review have been selected on the basis of their congruence to particular extraterrestrial locations. Terrestrial field sites that have been used most often in the literature, as well as some lesser known ones which require greater study, are incorporated to inform on the astrobiological potential of Venus, Mars, Europa, Enceladus and Titan. For example, the possibility of an aerial habitable zone on Venus has been hypothesized based on studies of life at high-altitudes in the terrestrial atmosphere. We also demonstrate why many different terrestrial analogue sites are required to satisfactorily assess the habitability of the changing environmental conditions throughout Martian history, and recommend particular sites for different epochs or potential niches. Finally, habitable zones within the aqueous environments of the icy moons of Europa and Enceladus and potentially in the hydrocarbon lakes of Titan are discussed and suitable analogue sites proposed. It is clear from this review that a number of terrestrial analogue sites can be applied to multiple planetary bodies, thereby increasing their value for astrobiological exploration. For each analogue site considered here, we summarize the pertinent physiochemical environmental features they offer and critically assess the fidelity with which they emulate their intended target locale. We also outline key issues associated with the existing documentation of analogue research and the constraints this has on the efficiency of discoveries in this field. This review thus highlights the need for a global open access database for planetary analogues.

APA, Harvard, Vancouver, ISO, and other styles

46

Zhang, Qixing, Tiantian Li, Jingshan Luo, Bofei Liu, Junhui Liang, Ning Wang, Xiangbin Kong, et al. "Ti/Co-S catalyst covered amorphous Si-based photocathodes with high photovoltage for the HER in non-acid environments." Journal of Materials Chemistry A 6, no. 3 (2018): 811–16. http://dx.doi.org/10.1039/c7ta09569d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Dai, Yiqing, and Yu Bai. "Performance Improvement for Building Integrated Photovoltaics in Practice: A Review." Energies 14, no. 1 (December 31, 2020): 178. http://dx.doi.org/10.3390/en14010178.

Full text

Abstract:

Building integrated photovoltaic (BIPV) technologies are promising and practical for sustainable energy harvesting in buildings. BIPV products are commercially available, but their electrical power outputs in practice are negatively affected by several factors in outdoor environments. Performance improvement of BIPV applications requires mitigation approaches based on an understanding of these factors. A review was, therefore, conducted on this issue in order to providing guidance for practical applications in terms of the selection of proper PV technologies, temperature management, solar irradiation enhancement and avoidance of excessive mechanical strain. First, major types of PV cells used in BIPV applications were comparatively studied in terms of their electrical performances in laboratorial and outdoor environments. Second, temperature elevations were widely reported in outdoor BIPV applications, which may cause efficiency degradation, and the mitigation approaches may include air-flow ventilation, water circulation and utilization of phase change materials. The heat collected from the PV cells may also be further utilized. Third, mechanical strains may be transferred to the integrated PV cells in BIPV applications, and their effects on electrical performance PV cells were also discussed. In addition, the power output of BIPV systems increases with the solar irradiation received by the PV cells, which may be improved in terms of the location, azimuth and tilt of the cells and the transmittance of surface glazing. Suggestions for practical applications and further research opportunities were, therefore, provided.

APA, Harvard, Vancouver, ISO, and other styles

48

Cahya Prima, Eka, Brian Yuliarto, Suyatman, and Hermawan Kresno Dipojono. "Theoretical Investigation of Anthocyanidin Aglycones as Photosensitizers for Dye-Sensitized TiO₂ Solar Cells." Advanced Materials Research 1112 (July 2015): 317–20. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.317.

Full text

Abstract:

The aim of this study is to analyze dye electronic properties of anthocyanin aglycones to be used as photosensitizers for TiO2solar cells. The dye properties will be examined by the density functional theory (DFT) method at IEF-PCM(UFF)/B3LYP/6-31+G(d,p) levels under ethanol and water environments. The results show that the position of LUMOs of all dyes lying over TiO2ECBwill facilitate good electron transfer while their HOMOs, which are lower than the electrolyte redox potential energy, can facilitate good oxidized-dye regeneration. Flavilium cation dye is the best anthocyanidin aglycone due to the best electron injection spontaneity of -0.807 eV as well as the highest open circuit voltage of 1.669 V. On the other hand, quinonoidal base dye gives the best light harvesting efficiency of 69.24% due to the best oscillating strength character. Moreover, the solvent effect is the important aspect regarding the dye oxidation potential stabilization as well as the electron injection driving force.

APA, Harvard, Vancouver, ISO, and other styles

49

Gharanjig, Kamaladin, and Mozhgan Hosseinnezhad. "Effect of substituents moiety in organic sensitiser based on carbazole on the performance of nanostructure dye-sensitised solar cells." Pigment & Resin Technology 44, no. 5 (September 7, 2015): 292–99. http://dx.doi.org/10.1108/prt-09-2014-0077.

Full text

Abstract:

Purpose – The purpose of this paper is to prepare new organic dyes and use them as sensitisers in dye-sensitised solar cells. These dyes were synthesised and purified and then characterised by analytical techniques. Spectrophotometric evaluations of the prepared dyes were carried out in solution and on a nano-anatase TiO2 substrate to assess the possible changes in the status of the dyes in different environments. Finally, the photovoltaic properties were investigated in dye-sensitised solar cells. Design/methodology/approach – So as to synthesise dyes, N-substituents carbazole were utilised as the fundamental electron donor group and cyanoacrylic acid or acrylic acid as electron acceptor anchoring groups. Purified dyes were dissolved in solution and coated on TiO2 substrate. Finally, dye-sensitised solar cells were fabricated to determine the photovoltaic behaviour and conversion efficiency of each individual dye. Findings – The results showed that the dyes form j-type aggregates on the nano TiO2. The oxidation potential of synthesised carbazole dyes is > 0.2 V vs Fc/Fc+; hence, their high performance in dye-sensitised solar cells. Dye 3 exhibited 2.11 per cent of conversion efficiency in comparison to 2.89 per cent for the identical cells with Dye 9 containing cyanoacrylic acid which acted as the best acceptor group. Practical implications – The novel dyes look as promising as highly light fast, efficient dyes for dye-sensitised solar cells. Social implications – Organic dye provides low cost and less hazardous materials for dye-sensitised solar cells. Originality/value – A series of new organic dyes were synthesised as sensitisers for dye-sensitised solar cells for the first time.

APA, Harvard, Vancouver, ISO, and other styles

50

Noh, Young Wook, In Su Jin, Kyeong Su Kim, Sang Hyun Park, and Jae Woong Jung. "Reduced energy loss in SnO2/ZnO bilayer electron transport layer-based perovskite solar cells for achieving high efficiencies in outdoor/indoor environments." Journal of Materials Chemistry A 8, no. 33 (2020): 17163–73. http://dx.doi.org/10.1039/d0ta04721j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Solar cells, Extraterrestrial environments'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles