Search results for "heavy [meson]"
showing 10 items of 385 documents
Studying Chemical Properties of the Heaviest Elements: One Atom at a Time
2017
The search for heavier elements has been an exciting endeavor for nuclear scientists for many decades. This was invigorated after the first predictions that nuclear shell effects might render superheavy elements to have lifetimes long enough for their experimental study, or even their occurrence in Nature. A fascinating aspect concerns the question of their chemical properties: will they conform to the well-established structure of the Periodic Table of the Elements, or will so-called relativistic effects—a result of the high velocities of electrons in the vicinity of highly-charged nuclei—lead to dramatic deviations? Chemical studies of the heaviest elements are complicated by small produc…
Search for long-lived superheavy elements in the reaction of136Xe with238U
1978
A search with radiochemical methods for long-lived superheavy elements in 238U targets bombarded with intense beams of136Xe ions produced negative results. A formation cross section of ≤1×10−35 cm2 is deduced at 95% confidence level for nuclides with half-lives between 1 and 200 d.
Cold fusion of heavy ions paving the way to superheavy elements
2001
Abstract Significant progress has been made approaching superheavy elements. A shell-stabilized region near hassium has been discovered. Element 112 has been synthesized. Recently evidence for the creation of elements 114, 116, and 118 has been reported. The way to these superheavy nuclei was paved by the cold fusion of heavy ions. In this paper experimental methods for heavy-element research, which is essentially physics with single atoms, are presented together with recent experimental results. The observed nuclear properties are discussed in the framework of theoretical models. New instrumental developments including accelerators and radioactive beams are be addressed.
Search for Superheavy Elements in theU238+U238Reaction
1980
A search was made for spontaneously fissioning superheavy elements in damped collisions of two uranium nuclei. Different techniques were applied covering the elements 108 to 118 and approx. =126, and a half-life range from 1 ms to more than 1 yr. No evidence for superheavy elements was found at upper cross-section limits of 10/sup -32/, 10/sup -33/, and 10/sup -35/ cm/sup 2/ for half-lives from 1 to 100 ms, 100 ms to 1 d, and 1 d to 1 yr, respectively.
Study of Superheavy Elements at the GSI-SHIP
2006
STATUS OF SUPERHEAVY ELEMENT RESEARCH
1982
ABSTRACT A review is given on the search for superheavy elements in nature. Attempts to arrive at conclusive proofs have failed thus far, however. Attempts to produce superheavy elements in the laboratory by heavy-ion reactions proved negative results although a detection sensitivity of 10−35 cm2 corresponding to a production of a few atoms per experiment has been achieved. Two approaches have been followed: complete fusion and transfer of nucleons during damped collisions. The former is illustrated by the 48Ca + 248Cm reaction, the latter by the 238U + 238U and 238U + 248Cm reactions.
ATTEMPTS TO PRODUCE SUPERHEAVY ELEMENTS IN REACTIONS BETWEEN HEAVY NUCLEI
1978
Nuclear structure physics at GSI-challenges and perspectives
2001
Some characteristic examples from the ongoing GSI nuclear structure research programme are presented such as recent experimental results from nuclear reactions with exotic beams to explore the structure of halo nuclei, direct mass measurements in the storage ring, and the structure of heavy-elements. A brief outline of a next generation exotic beam facility will be given.
Untreated Opuntia ficus indica for the Efficient Adsorption of Ni(II), Pb(II), Cu(II) and Cd(II) Ions from Water
2023
The raw cladode of Opuntia ficus indica (OFI) was evaluated as a sustainable biosorbent for the removal of heavy metals (Ni, Pb, Cu, and Cd) from aqueous solutions. The functional groups of OFI were identified by employing DRIFT-FTIR and CP-MAS-NMR techniques before and after contact with the ions in an aqueous media, showing a rearrangement of the biomass structure due to the complexation between the metal and the functional groups. The adsorption process was studied in both single- and multi-component systems under batch conditions at different pHs (4.0, 5.0, and 6.0), different metal concentrations, and different biomass amounts. The results show that the raw OFI had a removal capacity a…