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The arrojadite enigma: II. Compositional space, new members, and nomenclature of the group
Crystal structure arrojadite analysis chemical (mineral) new minerals arrojadite(PbFe) ?uorarrojadite-(BaFe) arrojadite-(BaFe) optical properties XRD data
2013/12/6
A systematic chemical and structural investigation of arrojadite-group minerals has provided new data allowing us to design a consistent nomenclature scheme, approved by the IMA CNMMN (vote05-D). The ...
THE NOMENCLATURE OF EUDIALYTE-GROUP MINERALS
eudialyte eudialyte group nomenclature report Commission on New Minerals Mineral Names
2013/12/6
This is the final report on the nomenclature of eudialyte-group minerals by the Eudialyte Nomenclature Subcommittee established by the Commission on New Minerals and Mineral Names of the International...
Re-definition, nomenclature and crystal-chemistry of the hellandite group
Re-definition nomenclature crystal-chemistry hellandite group
2013/12/6
Detailed X-ray single-crystal structure refinements and complete (SIMS + EMPA) microprobe chemical analyses of a series of non-metamict samples of hellandite recently found in Latium (Italy),together ...
Recommended nomenclature for labuntsovite-group minerals
labuntsovite group nomenclature labuntsovite nenadkevichite korobitsynite vuoriyarvite lemmleinite kuzmenkoite organovaite paralabuntsovite, tsepinite karupm鰈lerite gutkovaite
2013/12/6
The present report contains recommendations on the nomenclature of the labuntsovite-group (LG) minerals based on a crystal-structural classification. The labuntsovite group includes hydrous titanium a...
REDEFINITION OF A MINERAL IN THE JOAQUINITE GROUP:ORTHOJOAQUINITE-(La)
new mineral species joaquinite group orthojoaquinite-(La) Il韒aussaq Greenland
2013/12/6
Orthojoaquinite-(La) from Il韒aussaq, Greenland, is a new member of the joaquinite group. Its description was published by Semenov et al. (1967); although the chemical analytical data indicated that La...
Geochronology and geochemistry of the Hekou Group in Sichuan Province, SW China
zircon geochronology Hekou Group Yangtze Block supercontinent Columbia
2017/4/11
The Hekou Group, an outcrop at the west margin of the Yangtze Block, consists of volcanic and sedimentary rocks of
sodic lava, sodic pyroclastic rocks, coarse to fine-grained siliciclastic rocks and ...
Proximal methods for the latent group lasso penalty
Structured sparsity proximal methods regularization
2012/11/23
We consider a regularized least squares problem, with regularization by structured sparsity-inducing norms, which extend the usual $\ell_1$ and the group lasso penalty, by allowing the subsets to over...
Group descent algorithms for nonconvex penalized linear and logistic regression models with grouped predictors
Group descent algorithms nonconvex penalized linear model logistic regression model grouped predictors
2012/11/22
Penalized regression is an attractive framework for variable selection problems. Often, variables possess a grouping structure, and the relevant selection problem is that of selecting groups, not indi...
The product structure of the equivariant K-theory of the based loop group of SU(2)
equivariant K-theory Lie group loop group based loop spaces
2012/6/30
Let G=SU(2) and let \Omega G denote the space of continuous based loops in G, equipped with the pointwise conjugation action of G. It is a classical fact in topology that the ordinary cohomology H^*(\...
The Geometric Invariants of Group Extensions
The Geometric Invariants Group Extensions Group Theory
2012/6/30
In this paper, we compute the {\Sigma}^n(G) and {\Omega}^n(G) invariants when 1 \rightarrow H \rightarrow G \rightarrow K \rightarrow 1 is a short exact sequence of finitely generated groups with K fi...
Examples of abelian surfaces with non-square Tate-Shafarevich group
Examples of abelian surfaces non-square Tate-Shafarevich group Number Theory
2012/6/30
In this article we show the existence of abelian surfaces over Q with Tate-Shafarevich groups having orders five times a square and seven times a square. To obtain this result, we explore the invarian...
On the graded quotients of the ring of Fricke characters of a free group
Ring of Fricke characters Automorphism groups of free groups Andreadakis-Johnson filtration
2012/6/27
First, we study a descending filtration of the ring of Fricke characters of a free group consisting of ideals on which the automorphism group of a free group acts. Then using it, we define a descendin...
A note on the unramified Brauer group of a homogeneous space
Unramified Brauer group homogeneous space linear algebraic group
2012/6/21
We give a new proof of the theorem stating that for any connected linear algebraic group G over an algebraically closed field k of characteristic 0 and for any closed connected subgroup H of G, the un...
Non-asymptotic Oracle Inequalities for the Lasso and Group Lasso in high dimensional logistic model
Logistic model Lasso Group Lasso High-dimensional
2012/6/19
We consider the problem of estimating a function $f_{0}$ in logistic regression model. We propose to estimate this function $f_{0}$ by a sparse approximation build as a linear combinaison of elements ...
Characterizing sequences for precompact group topologies
precompact group topology T -sequence TB-sequence characterizing sequence characterized subgroup Bembedded subgroup finest precompact extension
2012/6/19
A precompact group topology $\tau$ on an abelian group $G$ is called {\em single sequence characterized} (for short, {\em ss-characterized}) if there is a sequence $\mathbf{u}= (u_n)$ in $G$ such that...