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1.
Nanoscale ; 15(47): 19330-19338, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38009070

ABSTRACT

With the application of nanomaterials in seawater desalination technology increasing, the adjustable characteristics of carbon-based nanomaterials make it possible to use multiwalled carbon nanotube (MWCNT) materials in seawater desalination technology. In this study, Ni[Fe(CN)6]2 is loaded onto the inner wall of MWCNTs by the co-precipitation method to prepare MWCNTs with variable pore size, making it a switchable cage for NaCl. During the procedure, most of the Ni[Fe(CN)6]2 is transferred to the outer surface of the MWCNTs after adsorption, and NaCl is stored inside the MWCNTs (which have been proved by characterization); at the same time, Ni can improve the cell stability of Ni[Fe(CN)6]2. The effect of adsorbent reaction time and addition amount on the desalination performance of MWCNTs/Ni[Fe(CN)6]2 has been tested. According to the results, the best desalination performance of MWCNTs/Ni[Fe(CN)6]2 is 1354.6 mg g-1 when the reaction time is 0.5 h and the addition amount is 20 mg. After 3 cycles of adsorption and desorption, its desalting performance decreased to 242.3 mg g-1.

2.
Phys Chem Chem Phys ; 25(36): 24448-24458, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37655724

ABSTRACT

A structural mechanics and energy storage difunctional supercapacitor based on a geopolymer membrane injected with a 0.5 M Na2SO4 electrolyte and a pseudocapacitive electrode Mn7O13 is designed and assembled. The geopolymer membrane is prepared as a structural electrolyte with metakaolin and alkaline activator solution. The wide channels in the geopolymer matrix provide paths for ion movement. The Mn7O13 electrode is prepared by different hydrothermal treatments at different temperatures and times, and assembled with activated carbon and a geopolymer with different moduli to form a difunctional supercapacitor. The results show that the electrode sample annealed at 300 °C for 45 min after hydrothermal treatment at 160 °C for 24 h exhibits the best comprehensive performance. The specific capacitance of the electrode is 175.5 F g-1 (2392.6 F m-2) at 1 A g-1, and the specific capacitance of the difunctional structure supercapacitor assembled with a geopolymer with a modulus of 1.2 and cured for 28 days is 144.12 F g-1 (1960.0F m-2) at 1 A g-1 under 15 MPa.

3.
Dalton Trans ; 52(26): 9005-9016, 2023 Jul 04.
Article in English | MEDLINE | ID: mdl-37334523

ABSTRACT

Previous studies have found that high entropy oxides can be used as electrode materials for supercapacitors. However, there is still the problem of their low energy density. We tried to increase the energy density while increasing the specific capacitance of high entropy oxides from the potential window. Transition metal elements Fe, Co, Cr, Mn and Ni were selected for their electrochemical activity, and high entropy oxides were prepared by a sol-gel method under different calcination temperatures. The calcination temperature affects the structural morphology and crystallinity of the high entropy oxides and thus also affects the electrochemical performance. The spinel-phase (FeCoCrMnNi)3O4 with a high specific surface area of 63.1 m2 g-1 was prepared at a low calcination temperature of 450 °C. The specific capacitance is 332.2 F g-1 at a current density of 0.3 A g-1 in 1 M KOH electrolyte with a wide potential window of (-1, 0.6). An improved energy density of 103.8 W h kg-1 is reached via the designed microstructure of the high entropy oxide electrode.

4.
Langmuir ; 38(50): 15740-15746, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36493336

ABSTRACT

Oceans contain many freshwater resources and metal elements that people need, so the rational development of marine resources can solve the two major problems of shortage of freshwater resources and metal elements for people. To solve these two challenges, a system was designed to obtain freshwater resources and metallic elements simultaneously. An ion enrichment module was added to the conventional flow capacitor deionization system to collect metal elements while the seawater was deionized. A flowing electrode allows the metal elements to enter the flowing electrode through the desalination ability. It transports the metal elements to the enrichment module through the fluidity of the fluid while reducing the ion concentration at the flowing electrode, thus reducing the effect caused by the rejection of the same ion and collecting and enriching the metal elements. We purchased activated carbon to test the feasibility of the system with different mass fractions of activated carbon suspensions. The results showed that the elemental enrichment capacity of the system increased from 12.291 to 14.795 mg, and the enrichment rate increased from 13.536 to 16.294 mg cm-2 h-1 as the mass fraction of activated carbon increased. Thus, the system accomplished the goals of desalination and metal collection simultaneously.

5.
Front Oncol ; 12: 862297, 2022.
Article in English | MEDLINE | ID: mdl-35720017

ABSTRACT

Background: First-line surveillance on hepatitis B virus (HBV)-infected populations with B-mode ultrasound is relatively limited to identifying hepatocellular carcinoma (HCC) without elevated α-fetoprotein (AFP). To improve the present HCC surveillance strategy, the state of the art of artificial intelligence (AI), a deep learning (DL) approach, is proposed to assist in the diagnosis of a focal liver lesion (FLL) in HBV-infected liver background. Methods: Our proposed deep learning model was based on B-mode ultrasound images of surgery that proved 209 HCC and 198 focal nodular hyperplasia (FNH) cases with 413 lesions. The model cohort and test cohort were set at a ratio of 3:1, in which the test cohort was composed of AFP-negative HBV-infected cases. Four additional deep learning models (MobileNet, Resnet50, DenseNet121, and InceptionV3) were also constructed as comparative baselines. To evaluate the models in terms of diagnostic power, sensitivity, specificity, accuracy, confusion matrix, F1-score, and area under the receiver operating characteristic curve (AUC) were calculated in the test cohort. Results: The AUC of our model, Xception, achieved 93.68% in the test cohort, superior to other baselines (89.06%, 85.67%, 83.94%, and 78.13% respectively for MobileNet, Resnet50, DenseNet121, and InceptionV3). In terms of diagnostic power, our model showed sensitivity, specificity, accuracy, and F1-score of 96.08%, 76.92%, 86.41%, and 87.50%, respectively, and PPV, NPV, FPR, and FNR calculated from the confusion matrix were respectively 80.33%, 95.24%, 23.08%, and 3.92% in identifying AFP-negative HCC from HBV-infected FLL cases. Satisfactory robustness of our proposed model was shown based on 5-fold cross-validation performed among the models above. Conclusions: Our DL approach has great potential to assist B-mode ultrasound in identifying AFP-negative HCC from FLL found in surveillance of HBV-infected patients.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 119991, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34091359

ABSTRACT

In this work, we investigate the low-lying electronic states correlated to the first and the second dissociation channels of MgGa molecule, neglecting and including the spin-orbit coupling effect. High-level ab initio calculations have been performed by using the icMRCI + Q method. Potential energy curves, spectroscopic constants, electron configurations and dipole moments are derived and discussed. Molecular structures of several magnesium-group 13 diatomics have been probed and analyzed. Information associated with transition dipole moments, Franck-Condon factors, vibrational branching ratios and radiative lifetimes between the Ω states are also well characterized. It is anticipated this work will provide some inspiration for further studies on MgGa.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 237: 118301, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32375078

ABSTRACT

High-level ab initio computations have been performed on the experimentally unknown species SCl+. The low-lying Λ-S electronic states correlated to the first and the second dissociation channels as well as their corresponding Ω states have been investigated by the icMRCI+Q methodology employing basis sets up to quintuple-ζ quality. Information about potential energy curves, electron configurations, spectroscopic constants, dipole moments and transition properties are derived and discussed. The results for SCl+ represent an improvement over our previous theoretical descriptions for the ground state. In addition, several low-lying excited states that have not been accessed experimentally and theoretically are also been well characterized in this work. The accuracy of our predictions for SCl+ are verified by comparisons of spectroscopic constants and vibrational levels between our accompany SCl computations and those reported in literatures for the neutral species. The feasibility of performing laser cooling of SCl+ has also been discussed and the photoelectron spectrum of SCl+(X3Σ-) + e â† SCl(X2Π) is simulated.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117413, 2020 Jan 05.
Article in English | MEDLINE | ID: mdl-31369990

ABSTRACT

The twelve Λ-S electronic states of the first four dissociation limits of the MgSb molecule have been examined at the icMRCI+Q level employing basis sets of quintuple-ζ quality. The potential energy curves, vibrational levels and spectroscopic constants of the species have been investigated. The permanent dipole moments of the interested states are derived, and the transition dipole moments, Einstein emission coefficients, radiation lifetimes and Franck-Condon factors between selected states are also determined. Four Λ-S states of the first two dissociation limits split into seven Ω states under the effect of spin-orbit coupling. Characterizations of the MgSb low-lying Ω states are performed for the first time. In addition, the results and relevant data provided in this work on MgSb are compared with the antimony-IIA group and magnesium-VA group diatomic species. It is anticipated that this work will shed some light on further investigations of MgSb and other antimony-IIA group systems.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117667, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31698155

ABSTRACT

High-level ab initio computations have been performed on SnH+. The potential energy curves and spectroscopic constants of the low-lying Λ-S electronic states, as well as their associated Ω states, are derived at the icMRCI + Q level employing basis sets of quintuple-ζ quality. The transition dipole moments, Einstein coefficients, radiative lifetimes and Franck-Condon factors of three spin-forbidden transition bands ( [Formula: see text] , [Formula: see text] and [Formula: see text] ) are determined. Comparisons between our predictions and available experimental results indicate reasonable agreement. The spin-orbit coupling effect has been proved to affect these low-lying electronic states significantly.

11.
Nanotechnology ; 30(34): 345202, 2019 Aug 23.
Article in English | MEDLINE | ID: mdl-30840935

ABSTRACT

The excellent conductive surface electronic states of topological insulators make them suitable candidates for the next generation optoelectronic devices. Moreover, their unique semiconducting properties are favorable for building heterojunctions with other semiconductors. Here, we fabricated a low cost and broadband self-powered photodetector based on Sb2Te3 and Si. The photolithography and thermal evaporation technique were combined to fabricate a series of asymmetric planar Sb2Te3 electrodes on the surface of an n-type silicon substrate. An obvious asymmetrical current voltage curve occurred under dark conditions, which is ascribed to the asymmetry of each electrode. During the photodetection test, self-powered photodetection was obtained upon 940 nm light irradiation. Moreover, the photodetector exhibited fast and broadband photodetection from 365 nm to 940 nm with a response time less than 40 ms.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 208: 124-130, 2019 Feb 05.
Article in English | MEDLINE | ID: mdl-30308396

ABSTRACT

The Λ-S electronic states with respect to the lowest four dissociation limits of BeSb are investigated theoretically on the icMRCI + Q level employing basis set of quintuple-ζ quality. The geometrical parameters, potential energy curves, vibrational energy levels, spectroscopic constants for the twelve Λ - S states are obtained, analyzed and compared with those of the Beryllium-VA group diatomic family species where data are available. The permanent dipole moments, transition dipole moments, Einstein emission coefficients, radiative lifetimes and Franck-Condon factors for interested Λ - S states are also derived. Further assessments of the spin-orbit coupling effect are performed for states associated with the first two dissociation asymptotes of BeSb. Four Λ - S states split into seven Ω states, and some of the PECs are distorted significantly through the spin-orbit coupling effect, which is similar to its isovalent diatomics BeAs. In consideration of potential risks of manipulating beryllium-containing species directly, the information associated with molecular structures, spectroscopic parameters as well as transition properties that provide in this paper is anticipated to serve as guidelines for further researches of BeSb.

13.
Cell Rep ; 24(5): 1266-1277.e5, 2018 07 31.
Article in English | MEDLINE | ID: mdl-30067981

ABSTRACT

It is well established that fibrotic remodeling of the tumor microenvironment favors tumorigenesis, but whether fibrosis underlies malignant progression in other ways is unclear. Here, we report that adaptive myofibroblastic reprogramming of osteosarcoma stem cells (OSCs) results in a critical advantage when establishing lung macro-metastases and spheroid growth but does not affect the growth of primary lesions or monolayer cultures. FGFR2 signaling in OSCs initiates fibrosis, whereas the resultant fibronectin (FN) auto-deposition sustains fibrogenic reprogramming and OSC growth, resembling the process employed by non-malignant myofibroblasts to cause tissue fibrosis. Furthermore, we provide evidence that nintedanib targets the pan FGFR-FN axis to disrupt lung metastasis without affecting the bone lesion growth of OSCs. Thus, myofibroblastic reprogramming of human OSCs in the lungs might represent a druggable trait for treating a deadly metastatic complication.


Subject(s)
Cellular Reprogramming , Lung Neoplasms/secondary , Myofibroblasts/metabolism , Neoplastic Stem Cells/metabolism , Osteosarcoma/metabolism , Animals , Female , Fibronectins/metabolism , Fibrosis , Hep G2 Cells , Humans , Indoles/pharmacology , MCF-7 Cells , Mice, Inbred NOD , Mice, SCID , Myofibroblasts/drug effects , Myofibroblasts/pathology , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , Osteosarcoma/pathology , Protein Kinase Inhibitors/pharmacology , Receptor, Fibroblast Growth Factor, Type 2/metabolism
14.
Materials (Basel) ; 11(5)2018 May 04.
Article in English | MEDLINE | ID: mdl-29734710

ABSTRACT

In order to study the fracture behavior and structure evolution of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)-based polymer bonded explosive in thermal-mechanical loading, in-situ studies were performed on X-ray computed tomography system using quasi-static Brazilian test. The experiment temperature was set from −20 °C to 70 °C. Three-dimensional morphology of cracks at different temperatures was obtained through digital image process. The various fracture modes were compared by scanning electron microscopy. Fracture degree and complexity were defined to quantitatively characterize the different types of fractures. Fractal dimension was used to characterize the roughness of the crack surface. The displacement field of particles in polymer bonded explosive (PBX) was used to analyze the interior structure evolution during the process of thermal-mechanical loading. It was found that the brittleness of PBX reduced, the fracture got more tortuous, and the crack surface got smoother as the temperature rose. At lower temperatures, especially lower than glass transition temperature of binders, there were slipping and shear among particles, and particles tended to displace and disperse; while at higher temperatures, especially above the glass transition temperature of binders, there was reorganization of particles and particles tended to merge, disperse, and reduce sizes, rather than displacing.

15.
ACS Omega ; 3(8): 8803-8812, 2018 Aug 31.
Article in English | MEDLINE | ID: mdl-31459013

ABSTRACT

Lithium-ion capacitors (LICs) are noticed as a new-type of energy storage device with both capacitive mechanism and battery mechanism. The LICs own outstanding power density and energy density. In our work, an LIC was constructed by using a simple method to prepare a bimetallic sulfide of CoMoS4 nanoparticles as the anode and a self-made biochar [fructus cannabis's shells (FCS)] with excellent specific surface area as the cathode. The CoMoS4//FCS LIC demonstrated that the range of energy density is from 10 to 41.9 W h/kg and the range of power density is from 75 to 3000 W/kg in the meantime, and it also demonstrated a remarkable cycling performance with the capacitance retention of 95% after 10 000 cycles of charging-discharging at 1 A/g. The designed CoMoS4//FCS LIC device exhibits a superior electrochemical performance because of the CoMoS4 loose porous structure leading to excellent dynamic performance, which is conducive to the diffusion of electrolyte and lithium ion transport, and good electric double layer performance of biochar with large specific surface area could be achieved. Therefore, this bimetallic sulfide is a promising active material for LICs, which could be applied to electric vehicles in the future.

16.
RSC Adv ; 8(61): 35083-35093, 2018 Oct 10.
Article in English | MEDLINE | ID: mdl-35547080

ABSTRACT

A chemical process was developed to prepare N-doped micro-nano carbon spheres with multi-scale pore structures via carbonization of N-PF/PMMA interpenetrating polymer networks, which contain melamine resin as the nitrogen source, PF as the carbon source, and polymethylmethacrylate (PMMA) as the pore-former. The N-content of N-doped micro-nano carbon spheres was controlled by adjusting the mass ratio of melamine and phenol before polymerization. The N-doped micro-nano carbon spheres as electrode materials possess appropriate pore size distribution, higher specific surface area (559 m2 g-1) and consistently dispersed nitrogen atoms with adjustable doping content. These distinct characteristics endow the prospective electrode materials with excellent performance in electrochemical capacitors. In particular, N-CS-IPN-4 exhibits the highest specific capacitance of 364 F g-1 at 0.5 A g-1 in 6 M KOH aqueous electrolyte in a three-electrode system. It also possesses superior rate capability (57.7% retention at current densities ranging from 0.5 to 50 A g-1) and excellent cycling performance at 2 A g-1 (100% retention after 10 000 cycles). All these results confirm that the N-doped micro-nano carbon spheres are promising electrochemical capacitor materials, which possesses the advantages of simple preparation procedure, multi-scale pore structures, higher specific surface areas, easy adjustment of N-content and excellent electrochemical properties.

17.
J Mol Model ; 23(10): 275, 2017 Sep 10.
Article in English | MEDLINE | ID: mdl-28891015

ABSTRACT

In this work, we report the structure, mechanical properties, and vibrational spectra of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105), an energetic molecular crystal, with a first-principles method based on density functional theory (DFT) using the recentely developped HASEM package. The elastic constants, acoustic velocity, and parameters of equations of state were calculated, and the predicted ordering of stiffness constants is C 33 (38.5 GPa) > C 11 (24.0 GPa) > C 22 (17.7 GPa). We also investigated the structure and equation of state of LLM-105 under hydrostatic pressure up to 100 GPa. The predicted structures are in good agreement with experimental results available from ambient pressure to 20 GPa. Under compressions, the LLM-105 crystal exhibits anisotropic compressibility, with a highly incompressible response along the a-axis and c-axis. It is worth noting that there is a sudden change in the lattice parameters and change rate of volume at ~30 GPa. Based on the intermolecular interaction analysis and vibrational spectra, a phase transition at the hydrostatic pressure of ~30 GPa is predicted.

18.
Chem Commun (Camb) ; 52(84): 12426-12429, 2016 Oct 13.
Article in English | MEDLINE | ID: mdl-27711326

ABSTRACT

Ozonolysis of aromatic abietane (+)-carnosic acid (4) is used to create an important intermediate in an enantiomerically pure form, resulting in a simple, concise, readily scalable, and asymmetric synthesis of (-)-antrocin (1). This strategy not only provides an efficient approach to (-)-antrocin (1) synthesis but can also be readily adopted for the syntheses of optically pure (+)-asperolide C (2) and (-)-trans-ozic acid (3) from the naturally abundant aromatic abietanes (+)-podocarpic acid (5) and (+)-dehydroabietic acid (6). The strategy presented here is an example of the use of naturally occurring aromatic abietanes as a chiral pool and offers an account of the asymmetric synthesis of terpenoids.

19.
Chem Asian J ; 10(9): 1874-80, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26136342

ABSTRACT

The asymmetric total synthesis of (-)-maoecrystal V, a novel cytotoxic pentacyclic ent-kaurane diterpene, has been accomplished. Key steps of the current strategy involve an early-stage semipinacol rearrangement reaction for the construction of the C10 quaternary stereocenter, a rhodium-catalyzed intramolecular O-H insertion reaction, and a sequential Wessely oxidative dearomatization/intramolecular Diels-Alder reaction to forge the pentacyclic framework of maoecrystal V.


Subject(s)
Cytotoxins/chemical synthesis , Diterpenes/chemical synthesis , Catalysis , Cycloaddition Reaction , Cyclohexenes/chemistry , Cytotoxins/chemistry , Diterpenes/chemistry , Models, Molecular , Oxidation-Reduction , Rhodium/chemistry , Stereoisomerism
20.
Sci Rep ; 5: 9604, 2015 Apr 08.
Article in English | MEDLINE | ID: mdl-25853231

ABSTRACT

Inactivation of p53 and/or Rb pathways restrains osteoblasts from cell-cycle exit and terminal differentiation, which underpins osteosarcoma formation coupled with dedifferentiation. Recently, the level of p-S6K was shown to independently predict the prognosis for osteosarcomas, while the reason behind this is not understood. Here we show that in certain high-grade osteosarcomas, immature SSEA-4(+) tumor cells represent a subset of tumor-initiating cells (TICs) whose pool size is maintained by mTORC1 activity. mTORC1 supports not only SSEA-4(+) cell self-renewal through S6K but also the regeneration of SSEA-4(+) TICs by SSEA-4(-) osteosarcoma cell dedifferentiation. Mechanistically, active mTORC1 is required to prevent a likely upregulation of the cell-cycle inhibitor p27 independently of p53 or Rb activation, which otherwise effectively drives the terminal differentiation of SSEA-4(-) osteosarcoma cells at the expense of dedifferentiation. Thus, mTORC1 is shown to critically regulate the retention of tumorigenicity versus differentiation in discrete differentiation phases in SSEA-4(+) TICs and their progeny.


Subject(s)
Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Cell Transformation, Neoplastic/metabolism , Multiprotein Complexes/metabolism , Osteosarcoma/metabolism , Osteosarcoma/pathology , Stage-Specific Embryonic Antigens/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Bone Neoplasms/drug therapy , Bone Neoplasms/genetics , Bone Neoplasms/mortality , Cell Cycle/genetics , Cell Dedifferentiation , Cell Transformation, Neoplastic/genetics , Disease Models, Animal , Disease Progression , Epithelial-Mesenchymal Transition/genetics , Female , Heterografts , Humans , Mechanistic Target of Rapamycin Complex 1 , Multiprotein Complexes/genetics , Neoplasm Grading , Osteosarcoma/drug therapy , Osteosarcoma/genetics , Osteosarcoma/mortality , Prognosis , Retinoblastoma Protein/genetics , Retinoblastoma Protein/metabolism , Stage-Specific Embryonic Antigens/genetics , TOR Serine-Threonine Kinases/genetics , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
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