Synthesis, characterization and magnetic properties of four new organically templated metal sulfates [C5H14N2][M(II)(H2O)6](SO4)2, (M(II) = Mn, Fe, Co, Ni).

International audienceA series of novel organically templated metal sulfates, [C(5)H(14)N(2)][M(II)(H(2)O)(6)](SO(4))(2) with (M(II) = Mn (1), Fe (2), Co (3) and Ni (4)), have been successfully synthesized by slow evaporation and characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy, thermogravimetric analysis and magnetic measurements. All compounds were prepared using a racemic source of the 2-methylpiperazine and they crystallized in the monoclinic systems, P2(1)/n for (1, 3) and P2(1)/c for (2,4). Crystal data are as follows: [C(5)H(14)N(2)][Mn(H(2)O)(6)](SO(4))(2), a = 6.6385(10) Å, b = 11.0448(2) Å, c = 12.6418(2) Å, β = 101.903(10)°, V = 906.98(3) Å(3), Z = 2; [C(5)H(14)N(2)][Fe(H(2)O)(6)](SO(4))(2), a = 10.9273(2) Å, b = 7.8620(10) Å, c = 11.7845(3) Å, β = 116.733(10)°, V = 904.20(3) Å(3), Z = 2; [C(5)H(14)N(2)][Co(H(2)O)(6)](SO(4))(2), a = 6.5710(2) Å, b = 10.9078(3) Å, c = 12.5518(3) Å, β = 101.547(2)°, V = 881.44(4) Å(3), Z = 2; [C(5)H(14)N(2)][Ni(H(2)O)(6)](SO(4))(2), a = 10.8328(2) Å, b = 7.8443(10) Å, c = 11.6790(2) Å, β = 116.826(10)°, V = 885.63(2) Å(3), Z = 2. The three-dimensional structure networks for these compounds consist of isolated [M(II)(H(2)O)(6)](2+) and [C(5)H(14)N(2)](2+) cations and (SO(4))(2-) anions linked by hydrogen-bonds only. The use of racemic 2-methylpiperazine results in crystallographic disorder of the amines and creation of inversion centers. The magnetic measurements indicate that the Mn complex (1) is paramagnetic, while compounds 2, 3 and 4, (M(II) = Fe, Co, Ni respectively) exhibit single ion anisotropy

1-Methyl­piperazine-1,4-diium tetra­chloridozincate hemihydrate

The crystal structure of the title compound, (C5H14N2)[ZnCl4]·0.5H2O, is built up from discrete 1-methyl­piperazine­diium cations with chair conformation, tetrahedral tetrachloridozincate anions and uncoordinated solvent water mol­ecules linked together by three types of inter­molecular hydrogen bonds, viz. N—H⋯Cl, N—H⋯O and O—H⋯Cl

Classification of MRI brain tumors based on registration preprocessing and deep belief networks

In recent years, augmented reality has emerged as an emerging technology with huge potential in image-guided surgery, and in particular, its application in brain tumor surgery seems promising. Augmented reality can be divided into two parts: hardware and software. Further, artificial intelligence, and deep learning in particular, have attracted great interest from researchers in the medical field, especially for the diagnosis of brain tumors. In this paper, we focus on the software part of an augmented reality scenario. The main objective of this study was to develop a classification technique based on a deep belief network (DBN) and a softmax classifier to (1) distinguish a benign brain tumor from a malignant one by exploiting the spatial heterogeneity of cancer tumors and homologous anatomical structures, and (2) extract the brain tumor features. In this work, we developed three steps to explain our classification method. In the first step, a global affine transformation is preprocessed for registration to obtain the same or similar results for different locations (voxels, ROI). In the next step, an unsupervised DBN with unlabeled features is used for the learning process. The discriminative subsets of features obtained in the first two steps serve as input to the classifier and are used in the third step for evaluation by a hybrid system combining the DBN and a softmax classifier. For the evaluation, we used data from Harvard Medical School to train the DBN with softmax regression. The model performed well in the classification phase, achieving an improved accuracy of 97.2%

Synthesis, crystal structures and thermal behaviour of organic-inorganic hybrids incorporating a chiral diamine

This manuscript represents part of collaborative work with a Tunisian solid state chemistry lab. --author-supplied descriptio

Crystal structures of two enantiomorphous 2-ethylpiperazinediium hexaaquacopper sulfates (R or S)-C5H14N2 Cu(H2O)(6) (SO4)(2)

International audienceTwo new non-centrosymmetric copper sulfates are synthesized under slow evaporation conditions through the use of enantiomorphically pure sources of either (R)-2-methylpiperazine or (S)-2-methylpiperazine. Both crystallize in the non-centrosymmetric P2(1) space group, crystal data for [(R)-C5H14N2][Cu(H2O)(6)](SO4)(2) (I), a = 6.5276(2) , b = 11.1955(3) , c = 12.4559(4) , beta = 101.196(2)A degrees, Z = 2, V = 892.95(5) (3) and [(S)-C5H14N2][Cu(H2O)(6)](SO4)(2) (II), a = 6.5188(2) , b = 11.1786(2) , c = 12.4365(3) , beta = 101.205(1)A degrees, Z = 2, V = 888.99(4) (3). The three-dimensional structure networks for these compounds consist of isolated [Cu(H2O)(6)](2+) and [(R)-C5H14N2](2+) or [(S)-C5H14N2](2+) cations and SO (4) (2-) anions linked only by hydrogen bonds. The Cu atom is in a slightly distorted octahedral coordination environment. The crystal packings are influenced by cation-to-anion N-HaEuro broken vertical bar O and OW-HaEuro broken vertical bar O hydrogen bonds leading to an open framework structures

Preparation, crystal structure, and physical characterization of a new hybrid material (C5H9N3)ZnCl4 center dot H2O

International audienceAn organic-inorganic hybrid compound (C5H9N3)ZnCl4 center dot H2O was synthesized by slow evaporation and characterized by single-crystal X-ray diffraction, differential scanning calorimetry, thermogravimetry, temperature-dependent X-ray powder diffraction, infrared spectroscopy, and some preliminary theoretical calculations of non-linear optic activity. The compound crystallizes in the non-centrosymmetric space group Pca21 with unit cell parameters: a = 22.714(5), b = 7.313(5), c = 7.301(5) angstrom, Z = 4, and V = 1212.8(12) angstrom 3. The structure was solved using direct methods and refined by least-squares analysis [R1 = 0.0484 and wR2 = 0.1255]. It is built from isolated [ZnCl4]2- anions, 2,5-diaminopyridinediium [C5H9N3]2+ cations, and water molecules which are connected by a 3-D hydrogen-bond network. Thermodiffractometry and thermogravimetric analyses indicate that its decomposition proceeds through four stages leading to a new crystalline anhydrous phases