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Trauma is one of the most common conditions in the biomedical field. It is important to identify it quickly and accurately. However, when evanescent trauma occurs, it presents a great challenge to professionals. There are few reports on the establishment of a rapid and accurate trauma identification and prediction model. In this study, Fourier transform infrared spectroscopy (FTIR) and microscopic spectroscopy (micro-IR) combined with chemometrics were used to establish prediction models for the rapid identification of muscle trauma in humans and rats. The results of the average spectrum, principal component analysis (PCA) and loading maps showed that the differences between the rat muscle trauma group and the rat control group were mainly related to biological macromolecules, such as proteins, nucleic acids and carbohydrates. The differences between the human muscle trauma group and the human control group were mainly related to proteins, polysaccharides, phospholipids and phosphates. Then, a partial least squares discriminant analysis (PLS-DA) was used to evaluate the classification ability of the training and test datasets. The classification accuracies were 99.10% and 93.69%, respectively. Moreover, a trauma classification and recognition model of human muscle tissue was constructed, and a good classification effect was obtained. The classification accuracies were 99.52% and 91.95%. In conclusion, spectroscopy and stoichiometry have the advantages of being rapid, accurate and objective and of having high resolution and a strong recognition ability, and they are emerging strategies for the identification of evanescent trauma. In addition, the combination of spectroscopy and stoichiometry has great potential in the application of medicine and criminal law under practical conditions.

Novel nanoscale lanthanide and mixed lanthanide metal-organic frameworks with thermo-sensitive polymer as organic links were successfully prepared. They were obtained through biomimetic mineralization approach. This is the first report of fabrication of polymer-metal-organic frameworks via biomimetic mineralization. The particle size was in the range from 200 to 500 nm. The photoluminescent properties of the materials have also been studied. The fluorescence intensity changed in different solvent (N, N-dimethylformamide, tetrahydrofuran, ethanol, acetone, dichloromethane, water), so solvent recognition can be achieved by using the polymer-metal-organic frameworks. The materials are also very sensitive to water (even trace water) in the mixed solutions composed of water and organic solvents. Especially the mixed lanthanide polymer-metal-organic frameworks can be designed to a ratiometric fluorescent nanosensor. The novel fluorescence detection materials have very important potential applications in the field of chemical industry.

In this study, ZnO-TiO 2 nanocomposite arrays on Ti fabric were synthesized via a hydrothermal process, where the amorphous TiO 2 nanotube array was used as a precursor. The fabrication process involved the preparation of zinc acetate particles that were modified on TiO 2 nanotube arrays. These transformed the amorphous TiO 2 to crystallized ZnO-TiO 2 . The prepared samples were then characterized by X-ray diffractometer, field-emission scanning electron microscope, transmission electron microscope, energy-dispersive X-ray spectroscopy, and photoluminescence. Photodegradation test of methyl orange was examined using the ZnO-TiO 2 nanocomposite arrays on the Ti fabric. Following 60 min of UV irradiation nearly 100% photodegradation of the 20 mg L −1 methyl orange solution at pH = 10 was achieved. The degradation products were identified and the photocatalysis process was studied. The results obtained in the study will enable researchers to design a scalable, practical process for dye wastewater treatment.

Ammonium vanadate (NH 4 V 4 O 10 ) nanowire flowers and nanowires on titanium (Ti) foils are synthesized by hexamethylenetetramine (HMTA)-assisted hydrothermal reactions as a cathode material for lithium-ion battery. The as-prepared NH 4 V 4 O 10 nanowires are about 50 nm in diameter and several micrometers in length. The effects of reaction time, temperature and additive concentration on the resulting morphology are investigated. Reversible lithium intercalation behavior of the nanowires has been evaluated by cyclic voltammetry and galvanostatic discharge⿿charge cycling. The NH 4 V 4 O 10 nanowires on Ti foil deliver a high discharge capacity of 168.5 mA h g ⿿1 after 100 cycles between 2.0 and 4.0 V at 50 mA g ⿿1 . A high rate capability is obtained with a remaining discharge capacity of about 182.6 mA h g ⿿1 after 35 cycles at various rates. Further, the NH 4 V 4 O 10 nanowires on Ti foil have a higher discharge capacity of 330.5 mA h g ⿿1 after 100 cycles at 0.8⿿4.0 V at 50 mA g ⿿1 .

Two novel chelating anion nitronyl nitroxide radical bridged dinuclear lanthanide complexes [Tb2(hfac)4(NIT2PhO)2] (1) and [Ho2(hfac)4(NIT2PhO)2] (2) [hfac = hexafluoroacetylacetonate; NIT2PhO = 2-(2′-hydroxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide] were prepared and structurally characterized by single crystal X-ray diffraction, elemental analysis, and IR spectroscopy. Both complexes are dinuclear phenoxo-O anion bridged with the oxygen atom of the N–O group coordinated to a single Ln(hfac)2 unit. The central Ln atoms exhibit a heptacoordinated environment, and the shape around the metal atom is capped octahedral. This structure is first reported in the lanthanide-nitronyl nitroxide system. It provides an innovative approach to synthesize new dinuclear lanthanide-nitroxide-based complexes. Additionally, the magnetic properties of the two complexes are studied.

Two new lanthanide-radical complexes [Ln(Hfac)3(NIT-4PhAllO)2](Ln(III) = Gd (I), Tb (II); Hfac = hexafluoroacetylacetonate; NIT-4PhAllO = 4′-allyloxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been prepared and characterized in structurally as well as magnetically. Single crystal X-ray diffraction analyses reveal that two complexes are isostructural with mononuclear tri-spin structure, in which the metal ions are eight-coordinated in distorted dodecahedron geometry. The nitronyl nitroxide radicals act as monodentate ligands towards Ln(Hfac)3 unit through the oxygen atom of the nitronyl nitroxide group. Magnetic studies reveal that the Gd-coordinated nitroxide interaction is ferromagnetic.

Reaction of the nitronyl nitroxide radicals NIT-2thien or NIT-3Brthien with Ln(hfac)3·2H2O affords three new one-dimensional lanthanide–nitronyl nitroxide complexes [Ho(hfac)3(NIT-2thien)]n (1); [Ho(hfac)3(NIT-3Brthien)]n (2); [Eu(hfac)3(NIT-3Brthien)]n (3) (hfac = hexafluoroacetylacetonate; NIT-2thien = 2-(2′-thienyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide; NIT-3Brthien = 2-(3′-bromo-2′-thienyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide). They have been characterized by X-ray single crystal structure analysis, element analysis, infrared spectra, and direct current, alternating current magnetic susceptibility measurements. All compounds are composed of linear chains built up by Ln(hfac)3 units bridged by nitronyl nitroxide radicals through their NO groups. Magnetic studies reveal that the Eu-coordinated nitroxide and the radicals through the Eu atom interactions are antiferromagnetic.

Two new one-dimensional nitronyl nitroxide radical–LnIII chain complexes, [Gd(hfac)3(NIT-I)] (1) and [Tb(hfac)3(NIT-I)] (2) (hfac = hexafluoroacetylacetonate; NIT-I = 2-iodo-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide), have been synthesized. Both complexes have linear chain structures in which the NIT-I radical ligands link the Ln(hfac)3 units through the oxygen atoms of the nitronyl nitroxide groups. Direct-current magnetic studies show that the Gd complex is paramagnetic above 2.0 K, whereas the Tb complex exhibits 3D antiferromagnetic ordering with TN = 4.0 K. Furthermore, complex 2 possesses frequency-dependent ac magnetic susceptibilities, which suggests slow magnetic relaxation.

Three new complexes [Fe(L1)2(NCS)2(CH3OH)2] (I), [Co(L2)2(CH3OH)2(H2O)2](ClO4)2 · L2 · 2H2O (II), and [Co(L1)3(H2O)2](ClO4)2 · L1 (III) (L1 = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene; L2= 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) have been prepared and structurally characterized by X-ray single crystall diffraction. Complexes I and II are mononuclear. Complex III has a 1D chain structure. Complex I is assembled by intermolecular O-H⋯N hydrogen bonds leading to 2D structure. In complex II, mononuclear complex cations are linked into 1D chain through hydrogen bonds. Then the chains get into 2D structure by intermolecular O-H⋯N hydrogen bonds too. In complex III, coordinated ligand L1 acts as a ditopic bridge to produce 1D coordination chain. The self-complementary intermolecular O-H⋯N hydrogen bonds assemble the chains into 2D sheets.

Two new nitronyl nitroxide bridged one-dimensional lanthanide complexes [Dy(hfac)3(NIT-2thien)]n (1); [Dy(hfac)3(NIT-3Brthien)]n (2) (hfac = hexafluoroacetylacetonate; NIT-2thien = 2-(2′-thienyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide; NIT-3Brthien = 2-(3′-bromo-2′-thienyl)-4,4,5,5- tetramethyl-imidazoline-1-oxyl-3-oxide) have been successfully prepared. Single crystal X-ray crystallographic analysis reveals that both complexes consist of linear chains built up by Dy(hfac)3 units bridged by nitronyl nitroxide radicals through their NO groups. AC measurements indicate that two complexes are out-of-phase frequency-dependent suggesting single-chain magnet behavior.

Two new metal–organic frameworks (MOFs) [Co(btx)(bdc)(H 2 O)] n 1 and [Co 3 (btx) 3 (btc) 2 (H 2 O) 2 ] n 2 , (btx = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene; H 2 bdc = 1,4-terephthalate acid; H 3 btc = 1,3,5-benzenetricarboxylate acid) have been synthesized and characterized by single-crystal X-ray diffraction studies and low temperature magnetic measurements. Compounds 1 and 2 are three-dimensional compounds whose structures can be described as layers of Co 2 units ( 1 ) and Co 3 ( 2 ) units with the carboxylate groups acting as mono or bidentate ligand, which are further connected through the flexible bis(triazole) ligand. The study of the magnetic properties of 1 and 2 in the temperature range 2–300 K shows the occurrence of weak ferromagnetic interactions in 1 due to the anti – syn carboxylate bridge and weak antiferromagnetic interactions in 2 between the high-spin Co(II) ions.

Two nitronyl nitroxide radical-TbIII complexes, [Tb(hfac)3(NIT-3Py)]2 (1) and [Tb(hfac)3(NIT-4Py)]2 (2) {hfac = hexafluoroacetylacetonate; NIT-3Py = 2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide; NIT-4Py = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide} have been synthesized. Both complexes possess cyclic dimer structure in which each pyridyl-substituted radical links two different metal ions through the oxygen of nitroxide group and the pyridine nitrogen. DC magnetic studies show the TbIII ion interacts ferromagnetically with the directly bonding nitronyl nitroxide. Complex 1 exhibits magnetic slow relaxation resembling SMM behavior, while there are no clearly the frequency-dependent out-of-phase signals for complex 2.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Using new nitronyl nitroxide radical ligand 2-[4-(1-imidazole)phenyl]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (NITPhIm), three new complexes [M(hfac)2(NITPhIm)]2 (M = Cu(II) 1, Mn(II) 2, Co(II) 3; hfac = hexafluoroacetylacetonate) have been prepared. Three complexes possess cyclic dimer structure in which each NITPhIm radical links two different metal ions through the oxygen of nitroxide group and the nitrogen of imidazole. The magnetic studies show the copper(II) ion interacts ferromagnetically with the directly bonding nitronyl nitroxide while manganese(II) and cobalt(II) ions strong antiferromagnetically interact with the directly coordinated nitroxide groups. There is a weak antiferromagnetic coupling between the metal ion and the nitroxide through phenyl and imidazole rings of the radical ligand, which is agreement with spin polarization mechanism. The results show that the minor changes in the structure of radical ligand can change the magnetic behavior of radical–metal complex.

Saussurea involucrata grows in high mountain areas covered by snow throughout the year. The temperature of this habitat can change drastically in one day. To gain a better understanding of the cold response signaling pathways and molecular metabolic reactions involved in cold stress tolerance, genome-wide transcriptional analyses were performed using RNA-Seq technologies. A total of 199,758 transcripts were assembled, producing 138,540 unigenes with 46.8 Gb clean data. Overall, 184,416 (92.32%) transcripts were successfully annotated. The 365 transcription factors identified (292 unigenes) belonged to 49 transcription factor families associated with cold stress responses. A total of 343 transcripts on the signal transduction (132 upregulated and 212 downregulated in at least any one of the conditions) were strongly affected by cold temperature, such as the CBL-interacting serine/threonine-protein kinase (CIPKs), receptor-like protein kinases, and protein kinases. The circadian rhythm pathway was activated by cold adaptation, which was necessary to endure the severe temperature changes within a day. There were 346 differentially expressed genes (DEGs) related to transport, of which 138 were upregulated and 22 were downregulated in at least any one of the conditions. Under cold stress conditions, transcriptional regulation, molecular transport, and signal transduction were involved in the adaptation to low temperature in S. involucrata. These findings contribute to our understanding of the adaptation of plants to harsh environments and the survival traits of S. involucrata. In addition, the present study provides insight into the molecular mechanisms of chilling and freezing tolerance.

The reaction of salicylaldoxime (H2sao) with Mn(ClO4)2·6H2O, sodium 3,5-dinitrobenzoate and NEt4(OH) in MeOH/EtOH affords a MnIII hexanuclear compound [Mn6O2(sao)6(ArCO2)2(MeOH)2(EtOH)2(H2O)2] (ArCO2H = 3,5-dinitrobenzoic acid) (1). 1 contains [MnIII6(µ3-O)2]14+ core, with a known structural type in the family of Mn6 clusters. Temperature-dependent magnetic susceptibility study shows presence of predominant ferromagnetic interactions between MnIII ions. Alternating current (ac) susceptibility measurements reveal a frequency-dependent out-of-phase (χM′′) signal below 4 K, suggesting 1 to be a single-molecule magnet (SMM).

Three novel ring-like compounds formulated as [Ln(Phtfac)(3)(NITpPy)](2) (Ln(III) = Gd 1, Tb 2, Dy 3; HPhtfac = 4,4,4-trifluoro-1-phenylbutane-1,3-dione; NITpPy = 2-(4-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl-3-oxide) were synthesized and structurally and magnetically characterized. Three compounds possess cyclic dimer structure in which each pyridine substituted radical links two different metal ions through the oxygen of nitroxide group and the pyridine nitrogen. DC magnetic studies show the Ln(III) ion interacts ferromagnetically with the directly bonding nitronyl nitroxide. Both Tb(III) and Dy(III) clusters show frequency-dependent ac magnetic susceptibilities, indicating single-molecule magnet behavior. It is demonstrated that the β-diketonate coligand may play an important role in determining the magnetic relaxation for the lanthanide-radical system.

International audience; Reaction of Dy(hfac)3·2H2O (hfac = hexafluoroacetyl acetonate) with 2-(2-hydroxyphenyl)nitronyl nitroxide (NITPhOH) and 2-(5-bromo-2-hydroxyphenyl)nitronyl nitroxide (NIT5BrPhOH) yielded [Dy2(hfac)4(NITPhO)2] 1 and [Dy2(hfac)4(NIT5BrPhO)2] 2, respectively. These compounds are phenoxo-O bridged binuclear complexes with the radical unit of a ligand coordinated to a single Dy. The Ln centers exhibit a heptacoordinated environment. Despite having very similar structures, these compounds exhibit distinct magnetic behaviors. Compound 1 shows slow relaxation of its magnetization indicating single-molecule magnet behavior, while no frequency-dependent out-of-phase signals were found for complex 2. This difference is likely to result from electronic effects induced by halogen substitution.

The syntheses, crystal structures, and magnetochemical characterization are reported of a novel family of four pentanuclear manganese complexes, namely, [Mn(III)(5)(mu(3)-O)(2)(L(1))(4)(O(2)CMe)(3)(CH(3)OH)].1.5CH(3)OH.2.5H(2)O (1), [Mn(III)(5)(mu(3)-O)(2)(L(1))(4)(O(2)CPh)(3)(CH(3)OH)].2CH(3)OH.2.25CH(3)CN.1.5H(2)O (), [Mn(II)Mn(III)(4)(HL(2))(2)(L(2))(2)(O(2)C Me)(4))].CH(3)OH.H(2)O (3) and [Mn(II)Mn(III)(4)(HL(2))(2)(L(2))(2)(O(2)CPh)(4))].1.5H(2)O (4), where H(2)L(1) is 3,5-dibromosalicylidene-2-ethanolamine and H(3)L(2) is 3-(2-hydroxy-3,5-dibromobenzylideneamino)propane-1,2-diol. All the complexes can be obtained from a reaction system containing the trinuclear species [Mn(3)O(O(2)CR)(6)(Py)(3)](0/+) (R = Me or Ph) and H(2)L(1) or H(3)L(2) with similar procedures. Both cores in complexes 1 and 2 feature two mu(3)-O(2-) atoms, four L(1)(2-) ligands together with three RCO(2)(-) groups (R = Me or Ph) bridging five Mn(III) atoms to form an incomplete cubane extended at one face by an incomplete adamantane unit, which is an unprecedented structural type in Mn chemistry. Complexes 3 and 4 both have a rare [Mn(II)Mn(III)(4)(mu(2)-O(alkoxide))(6)](8+) core, which can be regarded as two {Mn(II)Mn(III)(2)(mu(2)-O(alkoxide))(3)} scalene triangles, sharing the Mn(II) vertex. The dc magnetic susceptibility studies in the 2-300 K range for complexes 1-4 reveal the presence of overall antiferromagnetic intracluster interactions. A simple 3-J model was found to be adequate to describe the variable-temperature dc susceptibility data of complexes 1-4. The results have allowed us to compare the obtained magnetic exchange with magneto-structural correlations found previously for manganese-oxo clusters.

A new nitronyl nitroxide bridged one-dimensional lanthanide complex [Tb(3)(hfac)(9)(NIT-2thien)(3)](n) (1) (NIT-2thien = 2-(2'-thienyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide) has been successfully prepared. Single crystal X-ray crystallographic analysis reveals that complex 1 consists of linear chains built up by Tb(hfac)(3) units bridged by NIT-2thien radicals through their NO groups; the chains run along the crystallographic a-axis. The magnetic behavior of complex 1 is quite unusual. The complex shows the concomitant existence of slow magnetic relaxation and three-dimensional magnetic ordering.