418 research outputs found
Morey and Les
In my book Equality for Inegalitarians, I combined a sufficientarian approach to the distribution of resources and opportunities with an egalitarian approach to the distribution of a more abstract good that I called āthe ability to live oneās life effectively.ā As I defined living effectively, it requires a degree of success in the pursuit of oneās rational aims, so there is an obvious danger that even if two people both have sufficient resources and opportunities, the difference in the amount by which they exceed the threshold will cause them to differ in their ability to live effectively. However, to block this implication, I argued that lacking the means to accomplish oneās ends is itself a reason to scale back oneās aspirations. By thus relativizing a personās rational aims to the resources and opportunities at his disposal, I attempted to reconcile my commitment to the equal distribution of the ability to live effectively with my acceptance of inequality at the level of resources and opportunities.
To illustrate what I had in mind, I offered an example involving the eponymously named Morey and Les. Even if Les has significantly fewer resources than Morey, I wrote, the two may still be equally able to live their lives effectively if the impact of Lesās having fewer resources and opportunities is simply to give him reason to reduce his aspirations by a commensurate amount. If Morey can afford an education at a top law school while the best that Les can do is a year at a local community college, then Moreyās rational ends may include a career in corporate law or high finance while Lesās may extend no further than a steady job at an auto body shop. Assuming that Les and Morey are both able to achieve their rational ends, and that nothing else prevents either one from living his life effectively, the prevailing economic inequality will not render their society unjust.
In the years since the bookās publication, this passage has proven troubling to readers who want more equality than I am willing to supply, and my aim in the current paper is to address some of the objections that it elicits. By confronting these objections head-on, I hope both to deflect their force and to clarify the vision that animates the account at which they are addressed
Monoenergetic Neutrinos from WIMP Annihilation in Jupiter
Weakly interacting massive particles (WIMPs) can be captured by the Sun and
annihilate in the core, which may result in production of kaons that can decay
at rest into monoenergetic 236 MeV neutrinos. Several studies of detection of
these neutrinos at DUNE have been carried out. It has been shown that if the
WIMP mass is below 4 GeV, then they will evaporate prior to annihilation,
suppressing the signal. Since Jupiter has a cooler core, WIMPs with masses in
the 1-4 GeV range will not evaporate and can thus annihilate into monoenergetic
neutrinos. We calculate the flux of these neutrinos near the surface of Jupiter
and find that it is comparable to the flux at DUNE for masses above 4 GeV and
substantially greater in the 1-4 GeV range. Of course, detecting these
neutrinos would require a neutrino detector near Jupiter. Obviously, it will be
many decades before such a detector can be built, but should direct detection
experiments find a WIMP with a mass in the 1-4 GeV range, it may be one of the
few ways to learn about the annihilation process. A liquid hydrogen time
projection chamber might be able to get precise directional information and
energy of these neutrinos (and hydrogen is plentiful in the vicinity of
Jupiter). We speculate that such a detector could be placed on the far side of
one of the tidally locked Amalthean moons; the moon itself would provide
substantial background shielding and the surface would allow easier deployment
of solar panels for power generation.Comment: 14 pages, 4 figure
Electrochemical investigation of novel reference electrode Ni/Ni(OH)ā in comparison with silver and platinum inert quasi-reference electrodes for electrolysis in eutectic molten hydroxide
An efficient and green energy carrier hydrogen (H2) generation via water splitting reaction has become a major area of focus to meet the demand of clean and sustainable energy sources. In this research, the splitting steam via eutectic molten hydroxide (NaOHāKOH; 49ā51 mol%) electrolysis for hydrogen gas production has been electrochemically investigated at 250ā300 Ā°C. Three types of reference electrodes such as a high-temperature mullite membrane Ni/Ni(OH)2, quasi-silver and quasi-platinum types were used. The primary purpose of this electrode investigation was to find a suitable, stable, reproducible and reusable reference electrode in a molten hydroxide electrolyte. Cyclic voltammetry was performed to examine the effect on reaction kinetics and stability to control the working electrode at different scan rate and molten salt temperature. The effect of introducing water to the eutectic molten hydroxide via the Ar gas stream was also investigated. When the potential scan rate was changed from 50 to 150 mV sā1, the reduction current for the platinum wire working electrode was not changed with newly prepared nickel reference electrode that designates its stability and reproducibility. Furthermore, increasing the operating temperature of molten hydroxides from 250 to 300 Ā°C the reduction potential of the prepared nickel reference electrode is slightly positive shifted about 0.02 V. This suggests that it has good stability with temperature variations. The prepared nickel and Pt reference electrode exhibited stable and reliable cyclic voltammetry results with and without the presence of steam in the eutectic molten hydroxide while Ag reference electrode exposed positive shifts of up to 0.1 V in the reduction potential. The designed reference electrode had a more stable and effective performance towards controlling the platinum working electrode as compared to the other quasi-reference electrodes. Consequently, splitting steam via molten hydroxides for hydrogen has shown a promising alternative to current technology for hydrogen production that can be used for thermal and electricity generation
The effect of variable operating parameters for hydrocarbon fuel formation from CO2 by molten salts electrolysis
The emission of CO2 has been increasing day by day by growing world population, which resulted in the atmospheric and environmental destruction. Conventionally different strategies; including nuclear power and geothermal energy have been adopted to convert atmospheric CO2 to hydrocarbon fuels. However, these methods are very complicated due to large amount of radioactive waste from the reprocessing plant. The present study investigated the effect of various parameters like temperature (200ā500 oC), applied voltage (1.5ā3.0 V), and feed gas (CO2/H2O) composition of 1, 9.2, and 15.6 in hydrocarbon fuel formation in molten carbonate (Li2CO3-Na2CO3-K2CO3; 43.5:31.5:25 mol%) and hydroxide (LiOH-NaOH; 27:73 and KOH-NaOH; 50:50 mol%) salts. The GC results reported that CH4 was the predominant hydrocarbon product with a lower CO2/H2O ratio (9.2) at 275 oC under 3 V in molten hydroxide (LiOH-NaOH). The results also showed that by increasing electrolysis temperature from 425 to 500 oC, the number of carbon atoms in hydrocarbon species rose to 7 (C7H16) with a production rate of 1.5 Ī¼mol/h cm2 at CO2/H2O ratio of 9.2. Moreover, the electrolysis to produce hydrocarbons in molten carbonates was more feasible at 1.5 V than 2 V due to the prospective carbon formation. While in molten hydroxide, the CH4 production rate (0.80ā20.40 Āµmol/h cm2) increased by increasing the applied voltage from 2.0ā3.0 V despite the reduced current efficiencies (2.30 to 0.05%). The maximum current efficiency (99.5%) was achieved for H2 as a by-product in molten hydroxide (LiOH-NaOH; 27:73 mol%) at 275 oC, under 2 V and CO2/H2O ratio of 1. Resultantly, the practice of molten salts could be a promising and encouraging technology for further fundamental investigation for hydrocarbon fuel formation due to its fast-electrolytic conversion rate and no utilization of catalyst
Electrochemical study of different membrane materials for the fabrication of stable, reproducible and reusable reference electrode
Ā© 2020 Fabrication of stable, reproducible and reusable reference electrodes for low energy and high-temperature steam splitting is of great interest for hydrogen fuel production without anthropogenic carbon dioxide (CO2) emission. This study has been conducted for the detection of suitable material for the fabrication of novel reference electrode. In the present scenario, this research is designed to fabricate a novel nickel reference electrode by using operating conditions of eutectic molten hydroxide (NaOH-KOH, 49ā51 mol%) at temperature 300 Ā°C in an ion-conducting membrane of alumina and mullite tube. Afterwards, the designed nickel reference electrode has been examined for its reusability and stability by using electrochemical technique and cyclic voltammetry. Five scans of cyclic voltammetry are performed for both membrane fabricated reference electrode. A slight positive shift in oxidation peaks is observed for mullite membrane electrode (64 mV from scan 1 to 5). The stability measurements are noted by changing the scan rate between 50 and 150 mV sā1. Furthermore, the results show that the Ni/Ni(OH)2 reference electrode covered with a mullite membrane is stable and reusable at 300 Ā°C temperature without any deterioration. The stability and reusability of prepared nickel reference electrode covered by mullite tube in the eutectic molten hydroxide were up to 9 days to carry out an electrochemical investigation, while for alumina tube reference electrode the stability and reliability were up to 3 days. The internal electrolytic material and ionic conductance can play an important role for future studies with this reference electrode along with optimisation of temperature and scan rate parameters
Anopheles gambiae Immune Responses to Human and Rodent Plasmodium Parasite Species
Transmission of malaria is dependent on the successful completion of the Plasmodium lifecycle in the Anopheles vector. Major obstacles are encountered in the midgut tissue, where most parasites are killed by the mosquito's immune system. In the present study, DNA microarray analyses have been used to compare Anopheles gambiae responses to invasion of the midgut epithelium by the ookinete stage of the human pathogen Plasmodium falciparum and the rodent experimental model pathogen P. berghei. Invasion by P. berghei had a more profound impact on the mosquito transcriptome, including a variety of functional gene classes, while P. falciparum elicited a broader immune response at the gene transcript level. Ingestion of human malaria-infected blood lacking invasive ookinetes also induced a variety of immune genes, including several anti-Plasmodium factors. Twelve selected genes were assessed for effect on infection with both parasite species and bacteria using RNAi gene silencing assays, and seven of these genes were found to influence mosquito resistance to both parasite species. An MD2-like receptor, AgMDL1, and an immunolectin, FBN39, showed specificity in regulating only resistance to P. falciparum, while the antimicrobial peptide gambicin and a novel putative short secreted peptide, IRSP5, were more specific for defense against the rodent parasite P. berghei. While all the genes that affected Plasmodium development also influenced mosquito resistance to bacterial infection, four of the antimicrobial genes had no effect on Plasmodium development. Our study shows that the impact of P. falciparum and P. berghei infection on A. gambiae biology at the gene transcript level is quite diverse, and the defense against the two Plasmodium species is mediated by antimicrobial factors with both universal and Plasmodium-species specific activities. Furthermore, our data indicate that the mosquito is capable of sensing infected blood constituents in the absence of invading ookinetes, thereby inducing anti-Plasmodium immune responses
Enhancing hydrogen production from steam electrolysis in molten hydroxides via selection of non-precious metal electrodes
Ā© 2020 Hydrogen Energy Publications LLC There are still gaps in the field of reference electrode that is needed to assist electrolysis in high temperature electrolytes (e.g. molten hydroxides) for H2 gas production. This research aims to fill the gaps by preparing Ni/Ni(OH)2 reference electrode and more importantly testing its effectiveness against important performance factors including; ion conducting membrane (e.g. mullite tubes), internal electrolyte composition, working temperature and electrochemical control (e.g. potential scan rate). Then, this reference electrode was used to study the electrocatalytic activity various cheaper working electrode materials including; stainless steel (St.st), Ni, Mo and Ag in comparison with Pt by the means of chronoamperometry and voltammetry. The effect of introducing steam into electrolyte (eutectic mixture of NaOH and KOH) on the electrocatalytic activity of these working electrodes was also studied. It was observed that the potential of hydrogen evolution with different working electrodes followed an order as; Pt > Ni > St. st > Ag > Mo (positive to negative). The performance of each working electrode was confirmed through chronoamperometry for hydrogen evolution at a constant potential of ā0.7 V. It was also found in cyclic voltammetry and confirmed by chronoamperometry that the introduction of steam was apparent as increasing the current density at cathodic limit for hydrogen evolution. This study could help to develop non-precious metal electrodes for the production of hydrogen fuel. In future, there will be a potential in the threshold concentration of steam for H2 gas production
Electrochemical production of sustainable hydrocarbon fuels from CO2 co-electrolysis in eutectic molten melts
Because of the heavy reliance of people on limited fossil fuels as energy resources, global warming has increased to severe levels because of huge CO2 emission into the atmosphere. To mitigate this situation, a green method is presented here for the conversion of CO2/H2O into sustainable hydrocarbon fuels via electrolysis in eutectic molten salts [(KCl-LiCl; 41:59 mol %), (LiOH-NaOH; 27:73 mol %), (KOH-NaOH; 50:50 mol %), and (Li2CO3-Na2CO3-K2CO3; 43.5:31.5:25 mol %)] under the conditions of 1.5-2 V and 225-475 Ā°C depending on the molten electrolyte used. Gas chromatography (GC) and GC-mass spectrometry (MS) techniques were employed to analyze the content of gaseous products. The electrolysis results in hydrocarbon production with maximum 59.30, 87.70, and 99% Faraday efficiencies in the case of molten chloride, molten hydroxide, and molten carbonate electrolytes under the temperatures of 375, 275, and 425 Ā°C, respectively. GC with a flame-ionization detector and a thermal conductivity detector and GC-MS analysis confirmed that H2 and CH4 were the main products in the case of molten chlorides and hydroxides at an applied voltage of 2 V, while longer-chain hydrocarbons (>C1) were obtained only in molten carbonates at 1.5 V. In this way, electricity is transformed into chemical energy. The heating values obtained from the produced hydrocarbon fuels are satisfactory for further application. The practice of using molten salts could be a promising and encouraging technology for further fundamental investigation of sustainable hydrocarbon fuel formation with more product concentrations because of their fast electrolytic conversion rate without the use of a catalyst
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