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1.
Angew Chem Int Ed Engl ; 63(5): e202316112, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38088222

RESUMO

Compensating the irreversible loss of limited active lithium (Li) is essentially important for improving the energy-density and cycle-life of practical Li-ion battery full-cell, especially after employing high-capacity but low initial coulombic efficiency anode candidates. Introducing prelithiation agent can provide additional Li source for such compensation. Herein, we precisely implant trace Co (extracted from transition metal oxide) into the Li site of Li2 O, obtaining (Li0.66 Co0.11 □0.23 )2 O (CLO) cathode prelithiation agent. The synergistic formation of Li vacancies and Co-derived catalysis efficiently enhance the inherent conductivity and weaken the Li-O interaction of Li2 O, which facilitates its anionic oxidation to peroxo/superoxo species and gaseous O2 , achieving 1642.7 mAh/g~Li2O prelithiation capacity (≈980 mAh/g for prelithiation agent). Coupled 6.5 wt % CLO-based prelithiation agent with LiCoO2 cathode, substantial additional Li source stored within CLO is efficiently released to compensate the Li consumption on the SiO/C anode, achieving 270 Wh/kg pouch-type full-cell with 92 % capacity retention after 1000 cycles.

2.
Adv Mater ; 36(13): e2312159, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38117030

RESUMO

Developing sacrificial cathode prelithiation technology to compensate for active lithium loss is vital for improving the energy density of lithium-ion battery full-cells. Li2CO3 owns high theoretical specific capacity, superior air stability, but poor conductivity as an insulator, acting as a promising but challenging prelithiation agent candidate. Herein, extracting a trace amount of Co from LiCoO2 (LCO), a lattice engineering is developed through substituting Li sites with Co and inducing Li defects to obtain a composite structure consisting of (Li0.906Co0.043▫0.051)2CO2.934 and ball milled LiCoO2 (Co-Li2CO3@LCO). Notably, both the bandgap and Li─O bond strength have essentially declined in this structure. Benefiting from the synergistic effect of Li defects and bulk phase catalytic regulation of Co, the potential of Li2CO3 deep decomposition significantly decreases from typical >4.7 to ≈4.25 V versus Li/Li+, presenting >600 mAh g-1 compensation capacity. Impressively, coupling 5 wt% Co-Li2CO3@LCO within NCM-811 cathode, 235 Wh kg-1 pouch-type full-cell is achieved, performing 88% capacity retention after 1000 cycles.

3.
Small ; 19(41): e2302912, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37312398

RESUMO

Lithium-rich manganese-based layered oxides (LRM) have garnered considerable attention as cathode materials due to their superior performance. However, the inherent structural degradation and obstruction of ion transport during cycling lead to capacity and voltage decay, impeding their practical applications. Herein, an Sb-doped LRM material with local spinel phase is reported, which has good compatibility with the layered structure and provides 3D Li+ diffusion channels to accelerate Li+ transport. Additionally, the strong Sb-O bond enhances the stability of the layered structure. Differential electrochemical mass spectrometry indicates that highly electronegative Sb doping effectively suppresses the release of oxygen in the crystal structure and mitigates successive electrolyte decomposition, thereby reducing structural degradation of the material. As a result of this dual-functional design, the 0.5 Sb-doped material with local spinel phases exhibits favorable cycling stability, retaining 81.7% capacity after 300 cycles at 1C, and an average discharge voltage of 1.87 mV per cycle, which is far superior to untreated material with retention values of 28.8% and 3.43 mV, respectively. This study systematically introduces Sb doping and regulates local spinel phases to facilitate ion transport and alleviate structural degradation of LRM, thereby suppressing capacity and voltage fading, and improving the electrochemical performance of batteries.

4.
ACS Chem Neurosci ; 14(13): 2425-2442, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37339428

RESUMO

Neuropeptides with the C-terminal Wamide (Trp-NH2) are one of the last common ancestors of peptide families of eumetazoans and play various physiological roles. In this study, we sought to characterize the ancient Wamide peptides signaling systems in the marine mollusk Aplysia californica, i.e., APGWamide (APGWa) and myoinhibitory peptide (MIP)/Allatostatin B (AST-B) signaling systems. A common feature of protostome APGWa and MIP/AST-B peptides is the presence of a conserved Wamide motif in the C-terminus. Although orthologs of the APGWa and MIP signaling systems have been studied to various extents in annelids or other protostomes, no complete signaling systems have yet been characterized in mollusks. Here, through bioinformatics, molecular and cellular biology, we identified three receptors for APGWa, namely, APGWa-R1, APGWa-R2, and APGWa-R3. The EC50 values for APGWa-R1, APGWa-R2, and APGWa-R3 are 45, 2100, and 2600 nM, respectively. For the MIP signaling system, we predicted 13 forms of peptides, i.e., MIP1-13 that could be generated from the precursor identified in our study, with MIP5 (WKQMAVWa) having the largest number of copies (4 copies). Then, a complete MIP receptor (MIPR) was identified and the MIP1-13 peptides activated the MIPR in a dose-dependent manner, with EC50 values ranging from 40 to 3000 nM. Peptide analogs with alanine substitution experiments demonstrated that the Wamide motif at the C-terminus is necessary for receptor activity in both the APGWa and MIP systems. Moreover, cross-activity between the two signaling systems showed that MIP1, 4, 7, and 8 ligands could activate APGWa-R1 with a low potency (EC50 values: 2800-22,000 nM), which further supported that the APGWa and MIP signaling systems are somewhat related. In summary, our successful characterization of Aplysia APGWa and MIP signaling systems represents the first example in mollusks and provides an important basis for further functional studies in this and other protostome species. Moreover, this study may be useful for elucidating and clarifying the evolutionary relationship between the two Wamide signaling systems (i.e., APGWa and MIP systems) and their other extended neuropeptide signaling systems.


Assuntos
Aplysia , Neuropeptídeos , Animais , Sequência de Aminoácidos , Moluscos , Peptídeos
5.
Sci Rep ; 13(1): 7662, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37169790

RESUMO

Neuropeptides are ubiquitous intercellular signaling molecules in the CNS and play diverse roles in modulating physiological functions by acting on specific G-protein coupled receptors (GPCRs). Among them, the elevenin signaling system is now believed to be present primarily in protostomes. Although elevenin was first identified from the L11 neuron of the abdominal ganglion in mollusc Aplysia californica, no receptors have been described in Aplysia, nor in any other molluscs. Here, using two elevenin receptors in annelid Platynereis dumerilii, we found three putative elevenin GPCRs in Aplysia. We cloned the three receptors and tentatively named them apElevR1, apElevR2, and apElevR3. Using an inositol monophosphate (IP1) accumulation assay, we demonstrated that Aplysia elevenin with the disulfide bond activated the three putative receptors with low EC50 values (ranging from 1.2 to 25 nM), supporting that they are true receptors for elevenin. In contrast, elevenin without the disulfide bond could not activate the receptors, indicating that the disulfide bond is required for receptor activity. Using alanine substitution of individual conserved residues other than the two cysteines, we showed that these residues appear to be critical to receptor activity, and the three different receptors had different sensitivities to the single residue substitution. Finally, we examined the roles of those residues outside the disulfide bond ring by removing these residues and found that they also appeared to be important to receptor activity. Thus, our study provides an important basis for further study of the functions of elevenin and its receptors in Aplysia and other molluscs.


Assuntos
Aplysia , Neuropeptídeos , Animais , Sequência de Aminoácidos , Aplysia/genética , Neuropeptídeos/química , Receptores Acoplados a Proteínas G/química , Dissulfetos
6.
Front Pharmacol ; 14: 1132066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37021048

RESUMO

The vasopressin/oxytocin signaling system is present in both protostomes and deuterostomes and plays various physiological roles. Although there were reports for both vasopressin-like peptides and receptors in mollusc Lymnaea and Octopus, no precursor or receptors have been described in mollusc Aplysia. Here, through bioinformatics, molecular and cellular biology, we identified both the precursor and two receptors for Aplysia vasopressin-like peptide, which we named Aplysia vasotocin (apVT). The precursor provides evidence for the exact sequence of apVT, which is identical to conopressin G from cone snail venom, and contains 9 amino acids, with two cysteines at position 1 and 6, similar to nearly all vasopressin-like peptides. Through inositol monophosphate (IP1) accumulation assay, we demonstrated that two of the three putative receptors we cloned from Aplysia cDNA are true receptors for apVT. We named the two receptors as apVTR1 and apVTR2. We then determined the roles of post-translational modifications (PTMs) of apVT, i.e., the disulfide bond between two cysteines and the C-terminal amidation on receptor activity. Both the disulfide bond and amidation were critical for the activation of the two receptors. Cross-activity with conopressin S, annetocin from an annelid, and vertebrate oxytocin showed that although all three ligands can activate both receptors, the potency of these peptides differed depending on their residue variations from apVT. We, therefore, tested the roles of each residue through alanine substitution and found that each substitution could reduce the potency of the peptide analog, and substitution of the residues within the disulfide bond tended to have a larger impact on receptor activity than the substitution of those outside the bond. Moreover, the two receptors had different sensitivities to the PTMs and single residue substitutions. Thus, we have characterized the Aplysia vasotocin signaling system and showed how the PTMs and individual residues in the ligand contributed to receptor activity.

7.
J Am Chem Soc ; 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029335

RESUMO

Element doping/substitution has been recognized as an effective strategy to enhance the structural stability of layered cathodes. However, abundant substitution studies not only lack a clear identification of the substitution sites in the material lattice, but the rigid interpretation of the transition metal (TM)-O covalent theory is also not sufficiently convincing, resulting in the doping/substitution proposals being dragged into design blindness. In this work, taking Li1.2Ni0.2Mn0.6O2 as a prototype, the intense correlation between the "disordered degree" (Li/Ni mixing) and interface-structure stability (e.g., TM-O environment, slab/lattice, and Li+ reversibility) is revealed. Specifically, the degree of disorder induced by the Mg/Ti substitution extends in the opposite direction, conducive to sharp differences in the stability of TM-O, Li+ diffusion, and anion redox reversibility, delivering fairly distinct electrochemical performance. Based on the established paradigm of systematic characterization/analysis, the "degree of disorder" has been shown to be a powerful indicator of material modification by element substitution/doping.

8.
Sci Bull (Beijing) ; 68(1): 65-76, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36581534

RESUMO

As a potential substitute for lithium-ion battery, sodium-ion batteries (SIBs) have attracted a tremendous amount of attention due to their advantages in terms of cost, safety and sustainability. Nevertheless, further improvement of the energy density of cathode materials in SIBs remains challenging and requires the activation of anion redox reaction (ARR) activity to provide additional capacity. Herein, we report a high-performance Mn-based sodium oxide cathode material, Na0.67Mg0.1Zn0.1Mn0.8O2 (NMZMO), with synergistic activation of ARR by cosubstitution. This material can deliver an ultra-high capacity of âˆ¼233 mAh/g at 0.1 C, which is significantly higher than their single-cation-substituted counterparts and among the best in as-reported MgMn or ZnMn-based cathodes. Various spectroscopic techniques were comprehensively employed and it was demonstrated that the higher capacity of NMZMO originated from the enhanced ARR activity. Neutron pair distribution function and resonant inelastic X-ray scattering experiments revealed that out-of-plane migration of Mg/Zn occurred upon charging and oxygen anions in the form of molecular O2 were trapped in vacancy clusters in the fully-charged-state. In NMZMO, Mg and Zn mutually interacted with each other to migrate toward tetrahedral sites, which provided a prerequisite for further ARR activity enhancement to form more trapped molecular O2. These findings provide unique insight into the ARR mechanism and can guide the development of high-performance cathode materials through ARR enhancement strategies.


Assuntos
Fontes de Energia Elétrica , Óxidos , Oxirredução , Íons , Eletrodos , Oxigênio
9.
Front Cardiovasc Med ; 9: 946137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082126

RESUMO

As a result of ongoing breakthroughs in cancer therapy, cancer patients' survival rates have grown considerably. However, cardiotoxicity has emerged as the most dangerous toxic side effect of cancer treatment, negatively impacting cancer patients' prognosis. In recent years, the link between non-coding RNAs (ncRNAs) and cancer therapy-induced cardiotoxicity has received much attention and investigation. NcRNAs are non-protein-coding RNAs that impact gene expression post-transcriptionally. They include microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). In several cancer treatments, such as chemotherapy, radiotherapy, and targeted therapy-induced cardiotoxicity, ncRNAs play a significant role in the onset and progression of cardiotoxicity. This review focuses on the mechanisms of ncRNAs in cancer therapy-induced cardiotoxicity, including apoptosis, mitochondrial damage, oxidative stress, DNA damage, inflammation, autophagy, aging, calcium homeostasis, vascular homeostasis, and fibrosis. In addition, this review explores potential ncRNAs-based biomarkers and therapeutic strategies, which may help to convert ncRNAs research into clinical practice in the future for early detection and improvement of cancer therapy-induced cardiotoxicity.

10.
J Biol Chem ; 298(10): 102440, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36049520

RESUMO

The protostome leucokinin (LK) signaling system, including LK peptides and their G protein-coupled receptors, has been characterized in several species. Despite the progress, molecular mechanisms governing LK peptide-receptor interactions remain to be elucidated. Previously, we identified a precursor protein for Aplysia leucokinin-like peptides (ALKs) that contains the greatest number of amidated peptides among LK precursors in all species identified so far. Here, we identified the first ALK receptor from Aplysia, ALKR. We used cell-based IP1 activation assays to demonstrate that two ALK peptides with the most copies, ALK1 and ALK2, activated ALKR with high potencies. Other endogenous ALK-derived peptides bearing the FXXWX-amide motif also activated ALKR to various degrees. Our examination of cross-species activity of ALKs with the Anopheles LK receptor was consistent with a critical role for the FXXWX-amide motif in receptor activity. Furthermore, we showed, through alanine substitution of ALK1, the highly conserved phenylalanine (F), tryptophan (W), and C-terminal amidation were each essential for receptor activation. Finally, we used an artificial intelligence-based protein structure prediction server (Robetta) and Autodock Vina to predict the ligand-bound conformation of ALKR. Our model predicted several interactions (i.e., hydrophobic interactions, hydrogen bonds, and amide-pi stacking) between ALK peptides and ALKR, and several of our substitution and mutagenesis experiments were consistent with the predicted model. In conclusion, our results provide important information defining possible interactions between ALK peptides and their receptors. The workflow utilized here may be useful for studying other ligand-receptor interactions for a neuropeptide signaling system, particularly in protostomes.


Assuntos
Aplysia , Inteligência Artificial , Neuropeptídeos , Receptores de Neuropeptídeos , Animais , Amidas , Aplysia/genética , Aplysia/metabolismo , Ligantes , Mutagênese , Neuropeptídeos/química , Neuropeptídeos/genética , Conformação Proteica , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/genética
11.
Sci Rep ; 12(1): 1213, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075137

RESUMO

Neuropeptides, as pervasive intercellular signaling molecules in the CNS, modulate a variety of behavioral systems in both protostomes and deuterostomes. Allatostatins are neuropeptides in arthropods that inhibit the biosynthesis of juvenile hormones. Based on amino acid sequences, they are divided into three different types in arthropods: allatostatin A, allatostatin B, allatostatin C. Allatostatin C (AstC) was first isolated from Manduca sexta, and it has an important conserved feature of a disulfide bridge formed by two cysteine residues. Moreover, AstC appears to be the ortholog of mammalian somatostatin, and it has functions in common with somatostatin, such as modulating feeding behaviors. The AstC signaling system has been widely studied in arthropods, but minimally studied in molluscs. In this study, we seek to identify the AstC signaling system in the marine mollusc Aplysia californica. We cloned the AstC precursor from the cDNA of Aplysia. We predicted a 15-amino acid peptide with a disulfide bridge, i.e., AstC, using NeuroPred. We then cloned two putative allatostatin C-like receptors and through NCBI Conserved Domain Search we found that they belonged to the G protein-coupled receptor (GPCR) family. In addition, using an inositol monophosphate 1 (IP1) accumulation assay, we showed that Aplysia AstC could activate one of the putative receptors, i.e., the AstC-R, at the lowest EC50, and AstC without the disulfide bridge (AstC') activated AstC-R with the highest EC50. Moreover, four molluscan AstCs with variations of sequences from Aplysia AstC but with the disulfide bridge activated AstC-R at intermediate EC50. In summary, our successful identification of the Aplysia AstC precursor and its receptor (AstC-R) represents the first example in molluscs, and provides an important basis for further studies of the AstC signaling system in Aplysia and other molluscs.


Assuntos
Aplysia/metabolismo , Neuropeptídeos/metabolismo , Sequência de Aminoácidos , Animais , Aplysia/genética , Células CHO , Cricetulus , Evolução Molecular , Neuropeptídeos/química , Neuropeptídeos/genética , Filogenia
12.
Oxid Med Cell Longev ; 2021: 1587922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745412

RESUMO

Ischemia-reperfusion (I/R) is a pathological process that occurs in many organs and diseases. Reperfusion, recovery of blood flow, and reoxygenation often lead to reperfusion injury. Drug therapy and early reperfusion therapy can reduce tissue injury and cell necrosis caused by ischemia, leading to irreversible I/R injury. Ferroptosis was clearly defined in 2012 as a newly discovered iron-dependent, peroxide-driven, nonapoptotic form of regulated cell death. Ferroptosis is considered the cause of reperfusion injury. This discovery provides new avenues for the recognition and treatment of diseases. Ferroptosis is a key factor that leads to I/R injury and organ failure. Given the important role of ferroptosis in I/R injury, there is considerable interest in the potential role of ferroptosis as a targeted treatment for a wide range of I/R injury-related diseases. Recently, substantial progress has been made in applying ferroptosis to I/R injury in various organs and diseases. The development of ferroptosis regulators is expected to provide new opportunities for the treatment of I/R injury. Herein, we analytically review the pathological mechanism and targeted treatment of ferroptosis in I/R and related diseases from the perspectives of myocardial I/R injury, cerebral I/R injury, and ischemic renal injury.


Assuntos
Ferroptose , Estresse Oxidativo , Traumatismo por Reperfusão/terapia , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/patologia
13.
J Phys Condens Matter ; 33(36)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34167105

RESUMO

The perovskite structure of manganate yields a series of intriguing physical properties. Based on the results of first-principles calculations, strontium manganate appears to undergo a magnetic phase transition and a metal-insulator transition-from antiferromagnetic insulator to ferromagnetic metal and then to ferromagnetic insulator-under isotropic volume expansion combined with oxygen octahedral distortions. Interestingly, the results show that increasing the Mn-O bond length and adding rotation of the oxygen octahedra can soften the breathing distortion and account for the insulator phase. We further build a simple model to explain such transitions. Due to electron transfer and the favoring of a hole state of ligandporbitals, the electron state transfer from2(t2g3)to2(eg1+t2g2)and then tot2g3eg1+(t2g3L̲1). Such rearrangement of charges is responsible for the transitions of its magnetic order and electronic structure. Furthermore, we calculate spin susceptibility under the bare conditions and random phase approximation. The magnetic order of the intermediate metal state of itinerant electrons behaves as a ferromagnetic.

14.
Inorg Chem ; 58(21): 14316-14324, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31622084

RESUMO

Two new cyano-bridged mixed-valence {FeIII2(µ-CN)4FeII2} clusters, {[(Tp)FeIII(CN)3]2[FeII(Py2N2)]2}·(ClO4)2·MeCN·Et2O (1·MeCN·Et2O), its solvent-free form (1), and {[(Tp)FeIII(CN)3]2[FeII(Me2Py2N2)]2}·(ClO4)2·5MeOH (2·5MeOH), were obtained [Tp = hydrotris(pyrazol-1-yl)borate; N,N'-bis(2-pyridylmethyl)-N,N'-bis(4-X-benzyl)-1,2-ethanediamine, Py2N2, X = H; Me2Py2N2, X = Me]. Complexes 1 and 2·5MeOH exhibit gradual thermally induced two-step spin-crossover behavior (SCO) at two FeII metal centers, and the transformation of high-spin (HS) to low-spin (LS) FeII ions with temperature was confirmed by a combination of X-ray crystallography, variable-temperature Fourier transform infrared, variable-temperature magnetic susceptibility, and 57Fe Mössbauer spectroscopy. Moreover, complexes 1·MeCN·Et2O and 1 exhibit a reversible single-crystal-to-single-crystal transformation, and complex 1 undergoes two-step SCO behavior with T1/2 = 178 and 93 K accompanied by symmetry breaking in the structure.

15.
Phys Chem Chem Phys ; 20(34): 22168-22178, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30116799

RESUMO

Combining the first-principles density functional method and crystal structure prediction techniques, we report a series of hexagonal two-dimensional transition metal borides including Sc2B2, Ti2B2, V2B2, Cr2B2, Y2B2, Zr2B2, and Mo2B2. Their dynamic and thermal stabilities are testified by phonon and molecular dynamics simulations. We investigate the potential of the two-dimensional Ti2B2 monolayer as an anode material for Li-ion and Na-ion batteries. The Ti2B2 monolayer possesses high theoretical specific capacities of 456 and 342 mA h g-1 for Li and Na, respectively. The very high Li/Na diffusivity with an ultralow energy barrier of 0.017/0.008 eV indicates an excellent charge-discharge capability. In addition, good electronic conductivity during the whole lithiation process is found by electronic structure calculations. The very small change in volume after the adsorption of one, two, and three layers of Li and Na ions indicates that the Ti2B2 monolayer is robust. These results highlight the suitability of Ti2B2 monolayer as well as the other two-dimensional transition metal borides as excellent anode materials for both Li-ion and Na-ion batteries.

16.
Phys Chem Chem Phys ; 20(2): 732-737, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29242875

RESUMO

Searching for new two-dimensional (2D) Dirac cone materials has been popular since the exfoliation of graphene. Herein, based on density functional theory, we predict a novel family of 2D Dirac cone materials in square transition-metal carbides MC6 (M = Mo, W) which show inherent stability confirmed by phonon spectrum analysis and ab initio molecular dynamics calculations. The Dirac point, located exactly at the Fermi level, mainly arises from the hybridization of M-dz2,x2-y2 and C-pz orbitals which gives rise to an ultrahigh Fermi velocity comparable to that of graphene. Moreover, strong spin-orbit coupling related to M-d electrons can generate large band gaps of 35 and 89 meV for MoC6 and WC6 monolayers, respectively, which allows MC6 materials to be operable at room temperature (26 meV), as candidates for nanoelectronics in the upcoming post-silicon era. The conceived novel stable metal-carbon framework materials provide a platform for designing 2D Dirac cone materials.

17.
Dalton Trans ; 45(43): 17254-17263, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713940

RESUMO

The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeFe} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC-SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure-property analysis discloses that the distorted {Fe4(µ-CN)4} core and deviations of bent ∠Fe-N[triple bond, length as m-dash]C angles play a key role in tuning the transition temperature of these similar mixed-valence {FeFe} complexes.

18.
Inorg Chem ; 54(20): 9687-9, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26447552

RESUMO

A cyano-bridged {Fe(III)2Co(II)2} complex exhibits reversible thermally and photoinduced intramolecular charge transfer. Its desolvated, MeOH-d4, and other analogues were compared to disclose the impact factors on the electron-transfer behavior of these {Fe(III)2Co(II)2} clusters.

19.
Zhonghua Wai Ke Za Zhi ; 47(5): 337-8, 2009 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-19595006

RESUMO

OBJECTIVE: To analyze the value of intraoperative ultrasonography (IOUS) in the diagnosis and therapy of insulinoma. METHODS: From January 2000 to December 2007, the application of intraoperative ultrasonography used in 44 cases with insulinoma who came from department of general surgery, First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. There were 19 males and 25 females in the group. Every case accepted operation and examination of IOUS. RESULTS: Tumor was accurately located and its adjacent structure was also clear by IOUS in 43 cases, the other one was islet cell hyperplasia, the detection rate of tumor was 100%. The complications: one case occurred pancreatic fistula, one occurred pancreatitis, and there was no biliary fistula and hemorrhage. CONCLUSIONS: Presently, IOUS is one simple and effective method to local insulinoma, and it could improve the success rate of operation and reduce complications.


Assuntos
Insulinoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Insulinoma/cirurgia , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia , Adulto Jovem
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