PubChem (https://pubchem.ncbi.nlm.nih.gov) is a key chemical information resource for the biomedical research community. Substantial improvements were made in the past few years. New data content was added, including spectral information, scientific articles mentioning chemicals, and information for food and agricultural chemicals. PubChem released new web interfaces, such as PubChem Target View page, Sources page, Bioactivity dyad pages and Patent View page. PubChem also released a major update to PubChem Widgets and introduced a new programmatic access interface, called PUG-View. This paper describes these new developments in PubChem.

/pdf/pubchem-2019-update-improved-access-to-chemical-data-140jmv6hsa.pdf

PubChem 2019 update: improved access to chemical data

https://escholarship.org/content/qt2dj9p3h4/qt2dj9p3h4.pdf?t=pmi3bw

ENDF/B-VIII.0: The 8th Major Release of the Nuclear Reaction Data Library with CIELO-project Cross Sections, New Standards and Thermal Scattering Data

This is the second part of the new evaluation of atomic masses, AME2020. Using least-squares adjustments to all evaluated and accepted experimental data, described in Part I, we derived tables with numerical values and graphs which supersede those given in AME2016. The first table presents the recommended atomic mass values and their uncertainties. It is followed by a table of the influences of data on primary nuclides, a table of various reaction and decay energies, and finally, a series of graphs of separation and decay energies. The last section of this paper provides all input data references that were used in the AME2020 and the NUBASE2020 evaluations.

The AME2016 atomic mass evaluation (II). Tables, graphs and references

The last decade has witnessed both quantitative and qualitative progresses in Shell Model studies, which have resulted in remarkable gains in our understanding of the structure of the nucleus. Indeed, it is now possible to diagonalize matrices in determinantal spaces of dimensionality up to 10^9 using the Lanczos tridiagonal construction, whose formal and numerical aspects we will analyze. Besides, many new approximation methods have been developed in order to overcome the dimensionality limitations. Furthermore, new effective nucleon-nucleon interactions have been constructed that contain both two and three-body contributions. The former are derived from realistic potentials (i.e., consistent with two nucleon data). The latter incorporate the pure monopole terms necessary to correct the bad saturation and shell-formation properties of the realistic two-body forces. This combination appears to solve a number of hitherto puzzling problems. In the present review we will concentrate on those results which illustrate the global features of the approach: the universality of the effective interaction and the capacity of the Shell Model to describe simultaneously all the manifestations of the nuclear dynamics either of single particle or collective nature. We will also treat in some detail the problems associated with rotational motion, the origin of quenching of the Gamow Teller transitions, the double beta-decays, the effect of isospin non conserving nuclear forces, and the specificities of the very neutron rich nuclei. Many other calculations--that appear to have ``merely'' spectroscopic interest--are touched upon briefly, although we are fully aware that much of the credibility of the Shell Model rests on them.

The shell model as a unified view of nuclear structure

Nuclear ground-state masses and deformations: FRDM(2012)

This paper is the second part of the new evaluation of atomic masses, Ame2012. From the results of a least-squares calculation, described in Part I, for all accepted experimental data, we derive here tables and graphs to replace those of Ame2003. The first table lists atomic masses. It is followed by a table of the influences of data on primary nuclides, a table of separation energies and reaction energies, and finally, a series of graphs of separation and decay energies. The last section in this paper lists all references to the input data used in Part I of this Ame2012 and also to the data included in the Nubase2012 evaluation (first paper in this issue).

http://iopscience.iop.org/article/10.1088/1674-1137/36/12/002/pdf

The Ame2012 atomic mass evaluation

This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T(1/2) ≥ 100 ns) states. All nuclides for which any experimental information is known were considered. NUBASE2016 covers all data published by October 2016 in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2016, the data available in the 'Evaluated Nuclear Structure Data File' (ENSDF) database were consulted and critically assessed for their validity and completeness. Furthermore, a large amount of new data and some older experimental results that were missing from ENSDF were compiled, evaluated and included in NUBASE2016. The atomic mass values were taken from the 'Atomic Mass Evaluation' (AME2016, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclides (TNN) were examined. This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as 'non-experimental' (flagged '#'). Evaluation procedures and policies used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties. AMDC: http://amdc.impcas.ac.cn/ Contents  The NUBASE2016 evaluation of nuclear propertiesAcrobat PDF (1.1 MB)  Table I. The NUBASE2016 table of nuclear and decay propertiesAcrobat PDF (706 KB)

https://iopscience.iop.org/article/10.1088/1674-1137/41/3/030001/pdf

The NUBASE2016 evaluation of nuclear properties

This is the first of two articles (Part I and Part II) that presents the results of the new atomic mass evaluation, AME2020. It includes complete information on the experimental input data that were used to derive the tables of recommended values which are given in Part II. This article describes the evaluation philosophy and procedures that were implemented in the selection of specific nuclear reaction, decay and mass-spectrometric data which were used in a least-squares fit adjustment in order to determine the recommended mass values and their uncertainties. All input data, including both the accepted and rejected ones, are tabulated and compared with the adjusted values obtained from the least-squares fit analysis. Differences with the previous AME2016 evaluation are discussed and specific examples are presented for several nuclides that may be of interest to AME users.

https://iopscience.iop.org/article/10.1088/1674-1137/abddb0/pdf

The AME 2020 atomic mass evaluation (I). Evaluation of input data, and adjustment procedures

This paper presents the Nubase2012 evaluation that contains the recommended values for nuclear and decay properties of nuclides in their ground and excited isomeric (T1/2≥100 ns) states. All nuclides for which some experimental information is known are considered. Nubase2012 covers all up to date experimental data published in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of Nubase2012, the data available in the "Evaluated Nuclear Structure Data File" (Ensdf) database were consulted, and critically assessed of their validity and completeness. Furthermore, a large amount of new and somewhat older experimental results that were missing in Ensdf were compiled, evaluated and included in Nubase2012. The atomic mass values were taken from the "Atomic Mass Evaluation" (Ame2012, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclei (TNN) were examined. This approach allowed to estimate, whenever possible, values for a range of properties, and are labeled in Nubase2012 as "non-experimental" (flagged "#"). Evaluation procedures and policies that were used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties.

https://iopscience.iop.org/article/10.1088/1674-1137/36/12/001/pdf

Filip G Kondev

Papers

The Ame2012 atomic mass evaluation

The AME2016 atomic mass evaluation (II). Tables, graphs and references

The NUBASE2016 evaluation of nuclear properties

The AME 2020 atomic mass evaluation (I). Evaluation of input data, and adjustment procedures

The Nubase2012 evaluation of nuclear properties