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1.
ACS Omega ; 9(20): 22423-22435, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38799353

ABSTRACT

This study presents the in situ synthesis of CNT@SrTiO3 nanocomposite films for the development of high-performance flexible supercapacitors. The synthesis process involved the use of organic-inorganic hybrid polymers containing metal elements as precursors for thermal decomposition reaction under a reducing atmosphere. Due to the formation of chemical bonding between Ti elements and the CNTs, the interface between STO and CNT surface could provide additional active sites for ion transport and storage. Thereby, the incorporation of SrTiO3 nanoparticles into CNTs enhanced the electrochemical performance of the resulting nanocomposite membranes. To further investigate the influence of STO content and synthesis temperature, we conducted a detailed analysis. The findings indicated that the CNT@STO film with 25% STO content, synthesized at 700 °C, and possessed optimal performance with an areal capacitance of 6682 mF·cm-2 at 5 mV·s-1. Furthermore, a symmetrical flexible supercapacitor assembled by two CNT@STO-25 electrodes demonstrated strong application potential in wearable devices, owing to its long cycle life, excellent flexibility, and high energy density of 430.2 µWh·cm-2 (corresponding power density of 4.5 mW·cm-2). Based on these results, we believe that this study provides a fresh idea for the development of novel flexible energy storage materials.

2.
Pak J Med Sci ; 39(3): 710-714, 2023.
Article in English | MEDLINE | ID: mdl-37250558

ABSTRACT

Objective: To investigate and analyze the clinical observation of porcine collagen membrane + artificial bovine bone granules guided tissue regeneration (GTR) combined with autologous concentration of growth factors (CGF) in the treatment of severe periodontitis bone defect. Methods: A total of 94 patients with severe periodontitis bone defects admitted to Shanxi Bethune Hospital from January 2019 to January 2022 were included. They were divided into two groups by simple randomization method. Patients in the control group were treated with porcine collagen membrane + artificial bovine bone granules GTR, while those in the observation group were treated with autologous CGF on the basis of the control group. Before and after treatment, periodontal clinical indicators [sulcus bleeding index (SBI), gingival retreat index (GR), probing depth (PD), clinical attachment loss (CAL), alveolar bone height (AH)] and bone resorption markers [Osteoprotegerin (OPG), bone gla protein (BGP), Type-1 collagen N-terminal peptide (NTX)] were compared between the two groups, and the incidence of postoperative complications in the two groups was recorded. Results: The total efficacy of observation group was significantly higher than that of control group (p<0.05). Three months after surgery, the observation group had lower levels of SBI, PD, CAL and NTX while higher levels of GR, AH, OPG and BGP than the control group (p<0.05). There was no significant difference in complication rate between the two groups (p>0.05). Conclusion: Porcine collagen membrane + artificial bovine bone granules GTR combined with autologous CGF boasts various benefits in the treatment of severe periodontitis bone defects, such as improvement of clinical outcomes, amelioration of periodontal tissue and inhibition of bone resorption.

3.
ACS Omega ; 6(42): 27994-28003, 2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34722999

ABSTRACT

A series of graphene oxide (GO)/lanthanum titanate (La2Ti2O7, LTO) fiber composites were prepared through a hydrothermal method. The LTO fibers were homogeneously dispersed between the GO sheets. The structure and micromorphology of the GO/LTO composites were systematically studied. The composite exhibited a high specific capacitance of 900.6 F g-1 at a current density of 1 A g-1 in the 1 M H2SO4 and 10 wt % sucrose aqueous solution as the electrolyte. With the extended potential window of 1.8 V, the fabricated asymmetric supercapacitor device delivered a maximum energy density of 94.0 Wh kg-1 at a power density of 750.1 W kg-1. The GO/LTO composites could be promising materials for energy storage.

4.
ACS Omega ; 6(38): 24720-24730, 2021 Sep 28.
Article in English | MEDLINE | ID: mdl-34604654

ABSTRACT

Although supercapacitors are considered to play a vital role in flexible electronic devices, there are still some problems that need to be overcome, such as low energy density and narrow electrochemical stability windows in aqueous electrolytes. Herein, we have successfully synthesized a series of Sr-modified La2Zr2O7 (LZO-x) nanofibers as a new electrode material by a facile electrospinning technique. To determine the best doping sample, the changes in structures and electrochemical performances of La2Zr2O7 (LZO-x) nanofibers with various Sr contents are investigated carefully. Then, the LZO-0.2 sample shows the highest capacitance (1445 mF·cm-2). Furthermore, we also develop a low-cost superconcentrated electrolyte, which achieves a wide electrochemical stability window of 2.7 V using a working electrode (LZO-0.2). Finally, we use the LZO-0.2 electrode and the superconcentrated electrolyte to fabricate a flexible supercapacitor device, which shows an excellent capacitance of 175 F·g-1 at a current density of 1.15 A·g-1. Moreover, the aqueous device has excellent cycle stability and outstanding flexibility, and the energy density of this device is 177.2 Wh·kg-1 and the corresponding power density is 1557.7 W·kg-1.

5.
ACS Omega ; 5(46): 29722-29732, 2020 Nov 24.
Article in English | MEDLINE | ID: mdl-33251408

ABSTRACT

Flexible all-solid-state supercapacitors have drawn more attention owing to the rapid growth of wearable electronic equipments. Herein, we have succeeded in synthesizing a series of Y-doped lanthanum titanate flexible self-supporting films (LSF-x, 0.1 ≤ x ≤ 0.5) and investigating the change of microstructures, morphological characteristics, and lattice structures of these films affected by different Y-doping contents. To further determine the optimum Y-doping content, we have explored the electrochemical properties of working electrodes prepared by LSF-x (0.1 ≤ x ≤ 0.5) samples as the main active material. As the LSF-0.2 electrode has the best areal capacitance of 1.3 F·cm-2 at 2 mA·cm-2, we use the LSF-0.2 electrodes and PVA-Na2SO4 gel to fabricate a flexible all-solid-state supercapacitor device. This device has a high areal capacitance of 255.9 mF·cm-2 at a current density of 2 mA·cm-2 with a high cell voltage of 2.1 V, while the corresponding energy density is 156.8 µWh·cm-2 with a power density of 2.1 mW·cm-2. Moreover, it also shows a long cycling life and outstanding flexibility. Therefore, the LSF-0.2 sample can be used as an excellent energy-storage material for a wearable electronic device.

6.
Food Res Int ; 137: 109446, 2020 11.
Article in English | MEDLINE | ID: mdl-33233126

ABSTRACT

Non-edible meat from fur-producing animals entering into meat consumption chain could pose a serious threat to public health. For the purpose of risk prevention and control of meat safety, in this study, marker peptides for discriminating non-edible meat of fur-producing animals (including fox, silver fox, blue fox, raccoon dog, ussuri raccoon dog, mink and American mink) from meat of food-providing animals (including pig, cattle, sheep and donkey) were explored by shot-gun proteomics and verified by target approach. Two mass spectrometry platforms combined with bioinformatic and chemometric tools were integratedly emloyed for method development. Meat samples were first subjected to in-solution protein digestion and the subsequently tryptic peptides were profiled and quantitated by ultra-high pressure liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q/TOF MS) with sequential windowed acquisition of all theoretical fragment ion mass spectra (SWATH-MS) mode. Candidate marker peptides screened by chemometric tools were further filtered for their biological specificity and detectability through bioinformatics analysis as well as multiple reaction monitoring (MRM) verification with UHPLC-triple quadrupole mass spectrometry (UHPLC-QQQ MS). As a result, 9 peptides, out of 104 candidates, were selected as markers for discriminating analysis, of which DQTLQEELAR was validated as primary indicator of non-edible meat from the concerned fur-producing animals. An MRM method based on the developed marker peptides for routine use was finally proposed for risk alarming of non-edible meat from fur-producing animals in food safety control.


Subject(s)
Meat , Proteomics , Animals , Cattle , Chromatography, High Pressure Liquid , Mass Spectrometry , Meat/analysis , Peptides , Sheep , Swine
7.
Chemistry ; 26(64): 14654-14664, 2020 Nov 17.
Article in English | MEDLINE | ID: mdl-32643796

ABSTRACT

With the rapid development of wearable electronics devices, there is increasing demand for the development of new flexible energy storage devices with high security, and this has become a hot research topic. Although flexible supercapacitors are considered to be high-performance energy-storage equipment because of their fast charging/discharging ability, long cycle life, good reliability, wide operating temperature range, and so on, there are still many drawbacks that need to be overcome. Herein, the La2 Zr2 O7 (LZO) thin film is synthesized as a new energy-storage material by using a facile electrospinning method and calcination at low temperature. In addition, the mechanism of producing the flexibility of this film is determined by TG, IR, and XRD analyses. As previous studies have suggested that the charge storage of the LZO film can be attributed to the mechanism of oxygen intercalation, the Y element is doped into the LZO film to increase the concentration of oxygen vacancies. The changes in structural and electrochemical properties of La2 Yx Zr2-x O3 (0≤x≤0.5) nanofibers (LNF-x) with increasing Y content are studied carefully to obtain the best doping sample. The LNF-0.1 sample shows the highest areal capacitance of 605.3 mF cm-2 at 2 mA cm-2 , so a symmetrical flexible device is fabricated with LNF-0.1 electrodes. This device has a high energy density (76.7 µW h cm-2 at 2 mW cm-2 ), good cycling stability, and excellent mechanical flexibility. This study thus provides a new research trend for portable and wearable electronics.

8.
ACS Omega ; 3(4): 4688-4694, 2018 Apr 30.
Article in English | MEDLINE | ID: mdl-31458690

ABSTRACT

A hierarchically porous zirconia (ZrO2) monolith was successfully fabricated by using bacterial cellulose (BC) as a biotemplate and preceramic polymer as a zirconium resource, via freeze-drying and two-step calcination process. Images of scanning electron microscopy showed that the ZrO2 monolith well-replicated a three-dimensional reticulated structure of pristine BC and possessed good morphology stability till 1100 °C in air. Results of N2 adsorption/desorption and mercury porosimetry analysis revealed the hierarchically porous structure and large specific area (9.7 m2·g-1) of the ZrO2 monolith, respectively. Patterns of X-ray powder diffraction indicated that the monoclinic phase and tetragonal phase coexisted in the ZrO2 monolith with the former as the main phase. In addition, the ZrO2 monolith possessed low bulk density (0.13 g·cm-3) and good mechanical strength. These properties suggest that the as-prepared ZrO2 monolith has a great potential to serve as an ideal catalyst or catalyst support.

9.
Neural Regen Res ; 11(3): 487-92, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27127491

ABSTRACT

Salvianolic acid B, an active pharmaceutical compound present in Salvia miltiorrhiza, exerts a neuroprotective effect in animal models of brain and spinal cord injury. Salvianolic acid B can promote recovery of neurological function; however, its protective effect on the myelin sheath after spinal cord injury remains poorly understood. Thus, in this study, in vitro tests showed that salvianolic acid B contributed to oligodendrocyte precursor cell differentiation, and the most effective dose was 20 µg/mL. For in vivo investigation, rats with spinal cord injury were intraperitoneally injected with 20 mg/kg salvianolic acid B for 8 weeks. The amount of myelin sheath and the number of regenerating axons increased, neurological function recovered, and caspase-3 expression was decreased in the spinal cord of salvianolic acid B-treated animals compared with untreated control rats. These results indicate that salvianolic acid B can protect axons and the myelin sheath, and can promote the recovery of neurological function. Its mechanism of action is likely to be associated with inhibiting apoptosis and promoting the differentiation and maturation of oligodendrocyte precursor cells.

10.
Dalton Trans ; 42(12): 4285-90, 2013 Mar 28.
Article in English | MEDLINE | ID: mdl-23344999

ABSTRACT

Soluble organometallic polymers containing zirconium and silicon were synthesized by a salt metathesis reaction. The molecular weight of the polymers was measured by GPC and the corresponding structures were identified by (13)C NMR and FT-IR. After heat treatment of the polymers under argon at 1400 °C for 2 h, ZrC/SiC composites with different molar ratios of crystalline phases were obtained and characterized by XRD, elemental analysis, SEM and Raman spectroscopy. The crystalline size of the composites was approximately 100 nm-200 nm and the elements were well distributed at the different sites in the ceramics. The Raman results indicated that the ceramic residue could be considered as ZrC/SiC/C ternary composites.

11.
Chin Med J (Engl) ; 123(9): 1149-53, 2010 May 05.
Article in English | MEDLINE | ID: mdl-20529554

ABSTRACT

BACKGROUND: With the rapid development of computer technology, digital medicine has become a new direction in surgery. The application of digital medicine in hepatic surgery is still at the early stage and less reported in the literature. The aim of this study was to apply digital medical technology in the context of hepatic surgery. METHODS: Data from 64-slice helical computed tomography of 17 patients, including 13 with hepatocellular carcinoma and 4 with hepatic hemangioma, were imported into independently developed medical image software program, segmentation and three-dimensional reconstruction were performed. The three-dimensional models were then processed with the FreeForm Modeling System. We used virtual surgical instruments to perform surgery on the models. Simulated surgeries included six hepatic segmentectomies, four left hemihepatectomies, three right hemihepatectomies for hepatocellular carcinoma, one hepatic segmentectomy, two stripping surgeries, and one irregular segmentectomy combined with stripping surgery for hemangioma. For resections involving more than three hepatic segments, total and residual functional hepatic volumes were measured before and after simulation surgery, and the resection ratio was calculated. RESULTS: The anatomy of the models was distinct and was used to localize lesions. We used virtual surgical instruments to perform simulated surgeries and used the models to optimize actual surgeries. We were able to minimize resection volume as well as surgical risk. CONCLUSIONS: Digital medical technology is helpful in the diagnosis of hepatic disease and in optimizing surgical plans. Three-dimensional models can decrease surgical risk and help prevent postoperative hepatic failure.


Subject(s)
Liver/diagnostic imaging , Liver/surgery , Tomography, X-Ray Computed/methods , Adult , Aged , Female , Humans , Male , Middle Aged
12.
Chemistry ; 16(7): 2231-9, 2010 Feb 15.
Article in English | MEDLINE | ID: mdl-20066703

ABSTRACT

A series of fused thiophenes composed of fused alpha-oligothiophene units as building blocks, end-capped with either styrene or 1-pentyl-4-vinylbenzene groups, has been synthesized through Stille coupling reactions. The compounds have been fully characterized by means of (1)H NMR spectrometry, high-resolution mass spectrometry, and elemental analysis. The molecules present a trans-trans configuration between their double bonds, which has been verified and confirmed by Fourier-transform infrared spectroscopy and single-crystal X-ray diffraction analysis. The X-ray crystal structures showed pi-pi overlap and sulfur-sulfur interactions between the adjacent molecules. The decomposition temperatures were all found to be above 300 degrees C, indicating that compounds of this series possess excellent thermal stability. The fact that no phase transition occurs at low temperature indicates that they should be well-suited for application in devices. Moreover, they possess low HOMO energy levels, based on cyclic voltammetry measurements, and suitable energy gaps, as determined from their thin-film UV/Vis spectra. Thin-film X-ray diffraction analysis and atomic force microscopy revealed high crystallinity on supporting substrates. In addition, as the substrate temperature has a significant influence on the morphology and the degree of crystallinity, the device performance could be optimized by varying the substrate temperature. These materials were found to exhibit optimal field-effect performance, with a mobility of 0.17 cm(2) V(-1) s(-1) and an on/off ratio of 10(5), at a substrate temperature of 70 degrees C.

13.
Zhonghua Wai Ke Za Zhi ; 47(12): 909-11, 2009 Jun 15.
Article in Chinese | MEDLINE | ID: mdl-19781244

ABSTRACT

OBJECTIVE: To study the value of digital medical technology in diagnosis and treatment of the hepatolithiasis. METHODS: 64-slice spiral computer tomography (CT) scan data of 14 cases (11 female, 3 male; median age, 48 years) with hepatolithiasis admitted from February to September 2008 were collected. The data were imported into medical image proceeding system (MIPS) for sequence segmenting and three-dimensional (3D) reconstruction. The reconstructed models were imported into FreeForm Modeling System for performing simulation surgery with simulation surgical instruments. According to the results of 3D reconstruction and simulation surgery, reasonable operation strategies were chosen. Finally, the value of clinical application of simulation surgery was evaluated according to the findings of clinical operation on hepatolithiasis patients and postoperative T-tube angiography. RESULTS: The 3D reconstructed models of 14 cases with hepatolithiasis revealed 7 cases of left liver hepatolithiasis, 2 cases of right liver hepatolithiasis, 5 cases of bilateral hepatolithiasis, including 6 cases of hepatolithiasis with common bile duct calculi, 6 cases of biliary system models with absolute stricture, 8 cases with relative stricture. The results were of agreement with clinical diagnosis. A variety of operation plans were simulated before operation. Simulation equipment used in process of simulation surgery was a powerful sense of feedback. CONCLUSIONS: Digital medical technology is helpful to understand the calculi distribution, bile ducts stricture and deformity. Through preoperative training, simulation surgery are able to guide for choosing operative strategies. It reduces the operation risks.


Subject(s)
Computer Simulation , Gallstones/diagnosis , Gallstones/surgery , Liver/pathology , Models, Anatomic , Adult , Aged , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Tomography, Spiral Computed
14.
J Org Chem ; 73(12): 4638-43, 2008 Jun 20.
Article in English | MEDLINE | ID: mdl-18494524

ABSTRACT

A new series of ladder-type heteroacenes containing both pyrrole and furan rings, 5,6-disubstituted diindolo[3,2-b:4,5-b']thiophenes (DITs), were effectively synthesized from N-functionalized 3,3'-dibromo-2,2'-biindoles undergoing intramolecular cyclization with bis(phenylsulfonyl) sulfide and organolithium. Single-crystal X-ray results demonstrate that 5,6-dipropyldiindolo[3,2-b:4,5-b']thiophene (4b) forms a herringbone-type of packing motif and 5,6-di(p-tolyl)diindolo[3,2-b:4,5-b']thiophene (4d) forms a parallel packing motif. Both of them have S-S contacts, enhancing the electronic transport between molecules. Their photophysical properties suggest that the skeleton of diindolo[3,2- b:4,5-b']thiophene is more favorable to aggregate in solid than that of indolo[3,2-b]carbazole. The large band gaps and low-lying HOMO energy levels could result in much better stability.

15.
Org Lett ; 9(20): 3917-20, 2007 Sep 27.
Article in English | MEDLINE | ID: mdl-17824615

ABSTRACT

N,N'-Bis(n-octyl)-2,3,6,7-tetrabromonaphthalene diimide (TBNDI) was synthesized by a new imidization reaction and characterized by HRMS, (1)H NMR, (13)C NMR, elemental analyses, FT-IR, UV-vis, and single-crystal X-ray analysis. The TBNDIs are the key precursors for the synthesis of core-tetrasubstituted-naphthalene diimides.

16.
Chem Commun (Camb) ; (26): 2750-2, 2006 Jul 14.
Article in English | MEDLINE | ID: mdl-17009451

ABSTRACT

Three new linear benzene-fused bis(tetrathiafulvalene) compounds (1-3) were easily synthesized by one-step phosphite-induced cross-coupling reactions; a solution processed organic field-effect transistor based on 2 shows high mobility of 0.02 cm2/Vs.

17.
J Phys Chem B ; 110(15): 7702-7, 2006 Apr 20.
Article in English | MEDLINE | ID: mdl-16610864

ABSTRACT

Four X-shaped oligothiophenes with different conjugation length were investigated as novel electron donors in single-layer bulk-heterojunction solar cells. The UV-vis absorption spectra of blends of compounds 1-4 with 1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C(61) show a remarkably red shift and broadening with increasing thiophene number at each of the four branches. The performance of the photovoltaic cells varied significantly with molecular structures of the four oligothiophenes. Conversion efficiencies increased from 0.008% to 0.8% with changing the electron donors from 1 to 4. The maximum incident photon-to-current conversion efficiency of the device based on 4 reaches 31.6%, much higher than those of three other compounds 1-3. Remarkable improvement of the device performance was achieved with increasing the substituted thiophene number. The results show that the photovoltaic effect is dependent on the structural characteristics and the film forming abilities of the X-shaped thiophenes.

18.
Chem Commun (Camb) ; (7): 755-7, 2006 Feb 21.
Article in English | MEDLINE | ID: mdl-16465330

ABSTRACT

Novel butterfly pyrene derivatives functionalized with trifluoromethylphenyl and thienyl aromatic groups in the 1-, 3-, 6- and 8-positions of pyrene cores and have been synthesized by Suzuki coupling reactions, and their crystal structures, optical and electrochemical properties investigated; additionally, the field effect transistor using as the active material exhibited a p-type performance.

19.
Org Lett ; 8(5): 867-70, 2006 Mar 02.
Article in English | MEDLINE | ID: mdl-16494461

ABSTRACT

1,6,7,12-Tetrabromoperylene-3,4,9,10-tetracarboxylic acid bisanhydride and the corresponding tetrabrominated perylene bisimide were first synthesized with high yields. The Suzuki coupling reaction of novel tetrabromoperylene bisimide with phenylbonoric acid was studied. The four bromines in the bay position of the perylene core were substituted successfully to yield 1,6,7,12-teraphenylperylene bisimide. The photochemical properties of the novel perylene bisimides were studied and presented.

20.
J Am Chem Soc ; 127(38): 13281-6, 2005 Sep 28.
Article in English | MEDLINE | ID: mdl-16173758

ABSTRACT

We present the synthesis and characterization of a fused-ring compound, dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dithiophene (pentathienoacene, PTA). In contrast to pentacene, PTA has a larger band gap than most semiconductors used in organic field-effect transistors (OFETs) and therefore is expected to be stable in air. The large pi-conjugated and planar molecular structure of PTA would also form higher molecular orders that are conductive for carrier transport. X-ray diffraction and atomic force microscopy experiments on its films show that the molecules stack in layers with their long axis upright from the surface. X-ray photoelectron spectroscopy suggests that there are no chemical bonds at the PTA/Au interface. OFETs based on the PTA have been constructed, and their performances as p-type semiconductors are also presented. A high mobility of 0.045 cm(2)/V s and an on/off ratio of 10(3) for a PTA OFET have been achieved, demonstrating the potential of PTA for application in future organic electronics.


Subject(s)
Thiophenes/chemistry , Transistors, Electronic , Electric Conductivity , Microscopy, Atomic Force , Molecular Structure , Semiconductors , Temperature , Thiophenes/chemical synthesis
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