Inhibition of methane and natural gas hydrate formation by altering the structure of water with amino acids

Natural gas hydrates are solid hydrogen-bonded water crystals containing small molecular gases. The amount of natural gas stored as hydrates in permafrost and ocean sediments is twice that of all other fossil fuels combined. However, hydrate blockages also hinder oil/gas pipeline transportation, and, despite their huge potential as energy sources, our insufficient understanding of hydrates has limited their extraction. Here, we report how the presence of amino acids in water induces changes in its structure and thus interrupts the formation of methane and natural gas hydrates. The perturbation of the structure of water by amino acids and the resulting selective inhibition of hydrate cage formation were observed directly. A strong correlation was found between the inhibition efficiencies of amino acids and their physicochemical properties, which demonstrates the importance of their direct interactions with water and the resulting dissolution environment. The inhibition of methane and natural gas hydrate formation by amino acids has the potential to be highly beneficial in practical applications such as hydrate exploitation, oil/gas transportation, and flow assurance. Further, the interactions between amino acids and water are essential to the equilibria and dynamics of many physical, chemical, biological, and environmental processes.11Ysciescopu

Precessing jet nozzle connecting to a spinning black hole in M87

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from General Relativity. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an eight to ten-year quasi-periodicity. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years in the position angle variation of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.Comment: 41 pages, 7 figures, 7 table

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???-????????? ????????? ????????? ?????? ?????????, ??? ?????? ???????????? ???????????? ???????????? ???????????????. AlOOH?????? Yoldas?????? ????????? ??????????????????, HCl/??????????????? ????????? 0.07??? ?????? ?????? ???????????? ????????? ????????? ????????????. ??? ?????? ????????? ??-???????????? ?????? ???????????? ????????? ???????????? ???????????????. ALOOH ?????? ???????????? ??????-??????-???????????? ???????????? ????????? ??? ??-???????????? ?????? ????????? ?????? ??-???????????? ?????? ???????????????. ????????????, ???????????? ??? ??????????????? 3?????? ???????????? ??????????????????, 0.8M??? ?????? 3????????? ??????-??????-??????????????? ?????? ???????????????. ??????-????????? ????????? ??? ??????????????? ??????????????????, ?????? ?????? ?????? ????????? ???????????? ????????? ???????????? ???????????? ???????????? ?????????. ???????????? CaO ????????? ???????????? ???????????? ???????????? ????????? ????????? ??? ?????????. ???????????? ????????? ????????? ???????????? ????????? ????????? ??? ?????????. Alumina composite membranes were manufactured using coating sols witch were synthesized through sol-gel method. The AlOOH sol, prepared with the Yoldas Method, appeared the most transparent and contained the smallest. Particles when the HCl/alkoxide molar ratio was 0.07. The same sol resulted in the unsupported ??-alumina membrane with the largest surface area. ??-Alumina layers with small pores were formed on top of the -alumina supports with larger pores by repeating the coating-drying-calcining cycle with AlOOH sols. Dip coating, vacuum coating and pump coating methods were applied and at least 3 coating-drying-calcining cycles were necessary with 0.8 M sols. Crack formation or peeling of coating layers were frequently observed when repeated coating-drying cycles were followed by final calcining or concentrated sols were used. Surfaces of alumina composite membranes could be modified with silica or CaO. Distribution of dopant could be controlled by changing the solutions.clos

Proposing a Simple Radiation Scale for the Public: Radiation Index

A new radiation scale is proposed. With empathy toward the vast majority of people who are not well versed in radiation and related matters, and thus suffering from misunderstanding that breeds unnecessary fear of radiation, the aim of proposing a new radiation scale, radiation index (RAIN), is to put the general public at ease with the concept of radiation. RAIN is defined in dimensionless numbers that relate any specific radiation dose to a properly defined reference level. As RAIN is expressed in plain numbers without an attached scientific unit, the public will feel comfortable with its friendly look, which in turn should help them understand radiation dose levels easily and allay their anxieties about radiation. The expanded awareness and proper understanding of radiation will empower the public to feel that they are not hopeless victims of radiation. The correspondence between RAIN and the specific accumulated dose is established. The equivalence will allow RAIN to serve as a common language of communication for the general public with which they can converse with radiation experts to discuss matters related to radiation safety, radiation diagnosis and therapy, nuclear accidents, and other related matters. Such fruitful dialogues will ultimately enhance public acceptance of radiation and associated technologies

Core ethical values of radiological protection applied to Fukushima case: reflecting common morality and cultural diversities

The International Commission on Radiological Protection (ICRP) has established Task Group 94 (TG94) to develop a publication to clarify the ethical foundations of the radiological protection system it recommends. This TG identified four core ethical values which structure the system: beneficence and non-maleficence, prudence, justice, and dignity. Since the ICRP is an international organization, its recommendations and guidance should be globally applicable and acceptable. Therefore, first this paper presents the basic principles of the ICRP radiological protection system and its core ethical values, along with a reflection on the variation of these values in Western and Eastern cultural traditions. Secondly, this paper reflects upon how these values can be applied in difficult ethical dilemmas as in the case of the emergency and post-accident phases of a nuclear power plant accident, using the Fukushima case to illustrate the challenges at stake.We found that the core ethical values underlying the ICRP system of radiological protection seem to be quite common throughout the world, although there are some variations among various cultural contexts. Especially we found that “prudence” would call for somewhat different implementation in each cultural context, balancing and integrating sometime conflicting values, but always with objectives to achieve the well-being of people, which is itself the ultimate aim of the radiological protection system

WAVE: Popularity-based and collaborative in-network caching for content-oriented networks

Abstract—In content-oriented networking, content files are typically cached in network nodes, and hence how to cache content files is crucial for the efficient content delivery and cache storage utilization. In this paper, we propose a content caching scheme, WAVE, in which the number of chunks to be cached is adjusted based on the popularity of the content. In WAVE, an upstream node recommends the number of chunks to be cached at its downstream node, which is exponentially increased as the request count increases. Simulation results reveal that the average hop count of content delivery of WAVE is lower than other schemes, and the inter-ISP traffic volume of WAVE is the second lowest (CDN is the lowest). Also, WAVE achieves higher cache hit ratio and fewer frequent cache replacements than other on-demand caching strategies. Index Terms—Content chunk caching, caching strategy, content-oriented networks I