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1.
J Nanosci Nanotechnol ; 20(3): 1814-1821, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492347

RESUMO

Graphene-oxide-wrapped magnetic Fe3O4 nanocluster (NC) composites (MC@GO) were prepared and their characteristics were analyzed by multiple characterization methods. Results indicated that the magnetic NCs (~400 nm in size) were composed of numerous Fe3O4 monocrystalline particles (30-50 nm in size) and MC@GO had stable structure, high saturation magnetization (61 emu/g) and specific surface area of 112.5 m²/g. The magnetic NCs were integrally and tightly encapsulated in the composites by silk-like GO sheets via electrostatic interaction. The formation mechanism for MC@GO is also discussed in detail herein. Fe3+ was reduced by ethylene glycol in the adopted synthesis scheme, to generate Fe3O4 monocrystalline particles that aggregated to form Fe3O4 NCs with rough surfaces. Subsequent SiO2 coating and positive charge introduction caused the GO sheets to firmly wrap around the magnetic NCs, resulting in novel GO wrapped magnetic NC composites. The Fe3O4 NCs contributed much to structure amelioration and performance enhancement of the final GO composites. The rough surfaces of Fe3O4 NCs were beneficial for the SiO2 coating and final wrapping of GO sheets. The good magnetic property and beneficial structure of MC@GO make it an ideal adsorbent, which was demonstrated in the current study using methylene blue (MB) as a model adsorbate. The maximum MB adsorption capacity for MC@GO reached 105.5 mg/g. This is the first study on GO-wrapped Fe3O4 NC composites and their potential use for environmental adsorption. Furthermore, this study provides a method for developing GO wrapped magnetic particle composites by tailoring the magnetic precursor.

2.
Opt Express ; 27(22): 32210-32216, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684437

RESUMO

Adaptive moment estimation (Adam) is a popular optimization method to estimate large-scale parameters in neural networks. This paper proposes the first use of Adam algorithm to fast and stably converge large-scale tap coefficients of polynomial nonlinear equalizer (PNLE) for 129-Gbit/s PAM8-based optical interconnects. PNLE is one of simplified Volterra nonlinear equalizer for making a trade-off between complexity and performance. Different from serial least-mean square (LMS) adaptive algorithm, Adam algorithm is a parallel processing algorithm, which can obtain globally optimal tap coefficients without being trapped in locally optimal tap coefficients. Timing error is one of the main obstacles to the PAM systems with high baud rate and high modulation order. Owing to parallel processing and global optimization, Adam algorithm has much better performance on resisting the timing error, which can achieve faster, more-stable and lower-MSE convergence compared to LMS adaptive algorithm. In conclusion, Adam algorithm shows great potential for converging the tap coefficients of PNLE in PAM8-based optical interconnects.

3.
Anal Chim Acta ; 1092: 126-131, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31708025

RESUMO

Organophosphate pesticides (OPs) are widely used around the world to control pests in agricultural, residential, and commercial settings. Ingestion of high-dose OPs could lead to acute toxicity, and persistent influence on health could result from acute poisoning or long-term exposure to low dose OPs. An easy to operate, low cost and home available OPs testing platform is urgently needed. Ambient light sensor (ALS) based smart phone colorimetric reader has the advantages of easy to operate, low cost, high accuracy and versatility. In this work, a novel ALS based smart phone colorimetric dipsticks (CDs) reader was reported for rapid monitoring OPs. In this method, acetylcholinesterase (ACHE) CDs was used to test OPs and results were analyzed using an ALS based reader according to the absorbance of ACHE CDs. The results obtained using the ALS based CDs reader were comparable to those obtained using gas chromatography-mass spectrometry (GC-MS) and Ellman assay. The ALS based CDs reader has the advantages of portable, low cost, and high accuracy, and therefore could act an effective platform for OPs monitoring.

4.
Nanotechnology ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703222

RESUMO

A vanadium bronze nanomaterial, ß-Na0.33V2O5 was facilely synthesized via a sol-gel method followed by annealing at high temperatures. Morphology of the sample was observed using scanning electron microscope (SEM) and transmission electron microscope (TEM), and crystal phase was determined by X-ray diffraction (XRD) spectroscopy. The as-prepared sample displays a morphology of nanorods, and have a pure crystalline phase with high crystallinity. When used as cathode material for rechargeable lithium batteries, the ß-Na0.33V2O5 nanorods fired at 400 oC exhibit better electrochemical properties at 2.0V cut-off voltage than those at 1.5V cut-off voltage. Over the voltage range of 2.0-4.0 V, they can deliver an initial capacity of 221 mAh g-1 at 0.5C rate, and retain 212 mAh g-1 after 200 cycles, accounting for a capacity fading of only 0.02% per cycle. At 5C rate, the discharge capacity still reaches 146 mAh g-1, displaying an outstanding rate capability. Control of electrochemical window is proved to be an effective strategy in boosting cycling stability of the ß-Na0.33V2O5 cathode in this work in spite of a discounted capacity. Results suggest the as-prepared ß-Na0.33V2O5 nanorods are promisingly used as high-performance cathode materials for rechargeable lithium batteries.

5.
Aging (Albany NY) ; 11(19): 8701-8709, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31613794

RESUMO

After spine surgery, venous thromboembolism (VTE) is not uncommon in aged patients. This study investigates time-to-event risk factors of postoperative VTE based on medical records of aged patients (age≥60 yr) between January 2013 and December 2018. All participants had undergone lower extremity ultrasonography pre- and postoperatively at the first, second, fourth, eighth, and twelfth weeks. Mann-Whitney U tests and chi-square tests were used for univariate analyses, and Cox regression was utilized for multivariate analyses. A total of 1620 cases were recruited, VTE group (N=382, 23.6%) and non-VTE group (N=1238, 76.4%), aged 67 (IQR 11) years and 65 (IQR 6) years, respectively. The univariate analyses indicated significant differences between the VTE and non-VTE groups regarding advanced age, VTE history, hypertension, fusion, hospital stay, FIB, HDL, D-dimer, and TC (all P<0.05). The Cox regression showed that advanced age (OR=1.108; 95% CI, 1.091-1.126), VTE history (OR=4.962; 95% CI, 3.849-6.397), and hypertension (OR=1.344; 95% CI, 1.084-1.667) were the risk factors for postoperative VTE (P<0.05). The time-to-event analyses indicated that the hazard of VTE formation was highest in the first postoperative week. In conclusion, advanced age, VTE history, and hypertension are main risks for VTE formation, particularly in the first postoperative week.

6.
ACS Nano ; 13(10): 11593-11602, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31592641

RESUMO

Dynamic changes of mitochondrial morphology play an important role in cellular metabolism. Real-time monitoring mitochondrial ultrastructural dynamics at nanometer-scale resolution is crucially desired for further understanding of the mitochondria-based cellular function. In this work, we introduce a fluorescent carbon dot, which can selectively target mitochondria in live cells (named as MitoCD). MitoCD can effectively accumulate in mitochondria regardless of the decrease or vanishing of mitochondrial membrane potential (MMP), enabling the exploration of MMP-independent mitochondrial process. Moreover, the MitoCD is a thiol-based reaction-free probe that target mitochondria without consuming the thiol groups from mitochondrial proteins. Additionally, the MitoCD possesses good photophysical properties under physiological conditions, such as burst-like blinking, high photon counts, and low "on"/"off" ratio, which are specifically suitable for localization-based nanoscopic imaging. According to the optical microscopic imaging results, dynamical fission and fusion processes from mitochondria have been observed in live cells. During mitophagy, it is found that reticular formation of the mitochondria gradually collapsed, and then a portion of mitochondria split and vanished. Owing to the attractive biological and special photophysical properties, this probe displays promising application in a variety of super-resolution based biological studies and will provide deep insight in mitochondrial metabolism.

7.
J Hazard Mater ; 384: 121254, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31586911

RESUMO

Ethidium bromide (EtBr) is an intercalating agent commonly used as nucleic acid fluorescent tag in various techniques of life science field. It is considered as a serious biohazard due to its mutagenicity and carcinogenicity. As such, developing high efficiency and low cost materials as cleanup kits is in urgent need although many methods have already been developed. In this study we take use of the affinity of organic cations for clay minerals of high cation exchange capacity (CEC) and large specific surface area (SSA) and tested the removal of EtBr using rectorite, a type of clay mineral made of 1:1 regularly mixed layers of illite and montmorillonite. Our results showed that the uptake of Et+ on rectorite could be as high as 400 mmol/kg and the removal of Et+ was extremely fast. Desorption of inorganic cation Ca2+ and sorption of counterion Br- revealed that cation exchange was the dominating mechanism of Et+ removal using rectorite. Thermal analyses revealed that the EtBr could be thermally destructed inside the interlayer of rectorite and the material could be thermally regenerated. Thus, clay minerals could have a great potential to be fabricated into cleanup kits for the removal of EtBr in case of spill.

8.
Zhongguo Gu Shang ; 32(9): 815-819, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31615177

RESUMO

OBJECTIVE: To explore the effect of selective lumbosacral posterior rhizotomy(SPR) on lower limb spasticity and gross motor function in patients with cerebral palsy. METHODS: From January 2018 to October 2018, 47 patients with cerebral palsy were treated with rehabilitation alone and SPR combined with rehabilitation. According to whether SPR was performed, the patients were divided into group A and group B. Group A was treated with rehabilitation combined with SPR at lumbosacral level, and group B was treated with rehabilitation alone. There were 23 cases in group A, including 15 males and 8 females, with an average age of (7.30±3.25) years old; 24 cases in group B, 13 males and 11 females, with an average age of (7.00±3.09) years old. Forty-seven patients were assessed with modified Ashworth(MAS) and Gross Motor Function Scale(GMFM-88 items) before and after treatment. The changes of MAS and GMFM-88 scores before and after treatment were compared to evaluate the degree of spasm and the improvement of gross motor function in the two groups. RESULTS: All 47 patients were followed up. At 6 months after treatment, the MAS classification of the two groups was significantly improved(P<0.05), and the improvement of group A was more obvious than that of group B(P<0.05). Six months after treatment, the D, E and total scores of GMFM-88 between two groups were significantly improved compared with those before operation(P<0.05). The improvement of D and total scores in group A was more obvious than that in group B. There was no significant difference in the improvement of area E between two groups. CONCLUSIONS: Selective posterior rhizotomy combined with rehabilitation can significantly improve the spastic state and gross motor function of lower limbs in children with cerebral palsy, and can effectively promote the reconstruction and recovery of motor function of lower limbs in children with cerebral palsy.


Assuntos
Paralisia Cerebral , Rizotomia , Paralisia Cerebral/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Extremidade Inferior , Masculino , Movimento , Espasticidade Muscular
9.
Opt Express ; 27(15): 20358-20372, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510131

RESUMO

Compared to glass walls with a positive curvature, those with a negative curvature have been proven to have stronger confinement of light. Therefore, we change the multi-layered air holes in a photonic crystal fiber into several negative curvature tubes. As a result, the confinement medium is shifted from a low-index cladding material into a special structure. The theoretical analysis shows that each vector eigenmode has a corresponding threshold value for the outer tube thickness. It means that we can confine the target modes and filter the unnecessary modes by shifting the outer tube thickness. After substantial investigation on this fiber, we obtain the appropriate values for each structural parameter and then fabricate this negative curvature ring-core fiber under the guidance of the simulation results. Firstly, we draw the central cane under vacuum condition, then stack the cane and six capillaries to form the preform, and finally draw the ring-core fiber by using vacuumization method. The fiber test experiment indicates that the fiber length should be at least 15 m∼20 m to form the donut facula, and the tested losses of OAM+1,1, OAM+2,1, OAM+3,1, and OAM+4,1 are 0.30 dB/m, 0.36 dB/m, 0.37 dB/m, and 0.42 dB/m, respectively.

10.
Rev Sci Instrum ; 90(8): 083101, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472633

RESUMO

We designed a dual-wavelength photon-counting laser interferometer for absolute distance measurement of noncooperative targets. The weak optical interference on the rough surface was measured by a single-photon detector. The range of nonambiguity of the dual-wavelength interferometer was less than 1.2 µm, as the maximum errors of Lg and Lr were 7.8 nm and 9.1 nm caused by the photon-counting measurement and the frequency shift of the two unlocked lasers. We integrated laser triangulation into the interferometer as a coarse measurement, thus increasing the range of nonambiguity to 6.5 mm. As a result, a measurement standard deviation of ∼18 nm was achieved within a range of 1.1 mm in the experiment.

11.
Nat Commun ; 10(1): 4049, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492867

RESUMO

Food production in green crops is severely limited by low activity and poor specificity of D-ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) in natural photosynthesis (NPS). This work presents a scientific solution to overcome this problem by immobilizing RuBisCO into a microfluidic reactor, which demonstrates a continuous production of glucose precursor at 13.8 µmol g-1 RuBisCO min-1 from CO2 and ribulose-1,5-bisphosphate. Experiments show that the RuBisCO immobilization significantly enhances enzyme stabilities (7.2 folds in storage stability, 6.7 folds in thermal stability), and also improves the reusability (90.4% activity retained after 5 cycles of reuse and 78.5% after 10 cycles). This work mimics the NPS pathway with scalable microreactors for continuous synthesis of glucose precursor using very small amount of RuBisCO. Although still far from industrial production, this work demonstrates artificial synthesis of basic food materials by replicating the light-independent reactions of NPS, which may hold the key to food crisis relief and future space colonization.

12.
Opt Express ; 27(14): 19615-19623, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503718

RESUMO

On-chip microlasers are desirable to meet the different control requirements and unique demands in different application scenarios. In this work, we obtained the on-chip microlaser by printing pixelated CdSe/ZnS colloidal quantum dots (CQDs), incorporating the quantum dot self-assembly mechanism and the external cavity-free configuration. The spectral purity of the microlaser can be significantly improved by slightly blending polymer into the CQD matrix. The quasitoroid profile was gradually changed to microdisks as the polystyrene (PS) concentration increased from 0 wt.% to 10 wt.%. Specially, when the PS solution varied from 0 wt.% to 1 wt.%, the lasing threshold of 1.4 µJ/mm2 was increased up to 14 µJ/mm2, meanwhile the emission wavelength range showed a 25 nm blue-shift approximately. The easy printing technologies and the low-cost polymer blending method employed in the obtained microlasers will further facilitate the development of printing photonics and electronics, especially in the high-performance microlaser displays and high-precision sensors.

13.
Cell Cycle ; 18(19): 2566-2579, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432742

RESUMO

This study is aimed to clarify the potential role of lncRNA LINC00899 in invasion and migration of spinal ependymoma cells through the FoxO pathway via RBL2. Spinal ependymoma related chip data (GSE50161 and GSE66354) was initially downloaded and differentially expressed lncRNAs were screened out. Fifty-eight cases of spinal ependymoma and normal ependymal tissues were collected. The effects of LINC00899 and RBL2 on the spinal ependymoma cell migration and invasion were determined using the third generation spinal ependymoma cells and transfection with LINC00899 vector, siRNA-LINC00899 and siRNA-RBL2. The expression of LINC00899, pathway and cell proliferation- and apoptosis-related factors was determined. Finally, we also detected cell proliferation, migration, invasion, cycle and apoptosis after transfection. Our results showed that LINC00899 was up-regulated in spinal ependymoma and RBL2 was confirmed as a target gene of LINC00899 and found to be involved in regulation of FoxO pathway. LINC00899 expression increased in spinal ependymoma tissues whereas RBL2 expression decreased. Moreover, we found that siRNA-LINC00899 could elevate RBL2, p21, p27 and Bax levels, decrease FoxO, Bcl-2, Vimentin, Annexin levels, reduced cell proliferation, migration and invasion and enhanced apoptosis. Taken together, our study suggests that down-regulated LINC00899 exerts anti-oncogenic effects on spinal ependymoma via RBL2-dependent FoxO, which provides a novel therapeutic target for the treatment of spinal ependymomas.

14.
Opt Lett ; 44(16): 4067-4070, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415548

RESUMO

In this Letter, we explore the effectiveness of a Hadamard encoding algorithm (HEA) for efficiently suppressing glare. Both numerical simulations and experimental data show that light intensity decays exponentially with respect to the number of HEA measurements. Specifically, we applied the HEA to reduce the intensity of a single speckle to 4.1% of its original value within only 16 measurements. In contrast, the commonly used genetic algorithm (GA) can reduce the speckle intensity only to 0.2 of its original value even after 1200 measurements. Therefore, the HEA greatly outperforms the previously adopted GA in terms of efficiency. We further show that the HEA is also applicable to suppress the integrated intensity of many speckles.

15.
Biomed Res Int ; 2019: 4589056, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467892

RESUMO

Objective: To evaluate and compare the effects of repetitive transcranial magnetic stimulation (rTMS) over the right pars triangularis of the posterior inferior frontal gyrus (pIFG) and the right posterior superior temporal gyrus (pSMG) in global aphasia following subacute stroke. Methods: Fifty-four patients with subacute poststroke global aphasia were randomized to 15-day protocols of 20-minute inhibitory 1 Hz rTMS over either the right triangular part of the pIFG (the rTMS-b group) or the right pSTG (the rTMS-w group) or to sham stimulation, followed by 30 minutes of speech and language therapy. Language outcomes were assessed by aphasia quotient (AQ) scores obtained from the Chinese version of the Western Aphasia Battery (WAB) at baseline and immediately after 3 weeks (15 days) of experimental treatment. Results: Forty-five patients completed the entire study. The primary outcome measures include the changes in WAB-AQ score, spontaneous speech, auditory comprehension, and repetition. These measures indicated significant main effect between the baseline of the rTMS-w, rTMS-b, and sham groups and immediately after stimulation (P<0.05). Compared with the sham group, the increases were significant for auditory comprehension, repetition, and AQ in the rTMS-w group (P<0.05), whereas the changes in repetition, spontaneous speech, and AQ tended to be higher in the rTMS-b group (P<0.05). Conclusions: Inhibitory rTMS targeting the right pIFG and pSTG can be an effective treatment for subacute stroke patients with global aphasia. The effect of rTMS may depend on the stimulation site. Low-frequency rTMS inhibited the right pSTG and significantly improved language recovery in terms of auditory comprehension and repetition, whereas LF-rTMS inhibited the right pIFG, leading to apparent changes in spontaneous speech and repetition.

16.
Opt Lett ; 44(17): 4235-4238, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465370

RESUMO

In this Letter, a fiber-wireless integration system at Ka-band adopting heterodyne coherent detection is proposed and experimentally demonstrated. Optical I/Q up-conversion is realized with a low-cost dual-drive Mach-Zehnder modulator (DD-MZM) instead of the traditional I/Q nested MZM. To avoid non-convergence during constant-modulus-algorithm-based equalization, DC elimination is applied to suppress the ultra-high peak in the frequency domain after frequency down-conversion and symbol-phase-average-processing-based coarse phase noise estimation. Using DD-MZM for optical I/Q modulation, transmission, and reception of single polarization, 20-Gbit/s quadrature phase shift keying (QPSK) over 40-km single-mode fiber (SMF) and 5-m free space at Ka-band is demonstrated.

17.
Am J Otolaryngol ; 40(6): 102258, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31399243

RESUMO

OBJECTIVE: Tongue squamous cell carcinoma (TSCC) is one of the most common malignancies in the oral cavity, and its incidence and mortality have been constantly increasing these years. A large number of tumor suppressor genes are involved in the development of the TSCC and it has been reported that the aberrant hypermethylation of tumor suppressor genes may play a key role in the process of the TSCC. In this study, we sought to analyze the association of methylation of DcR1, DcR2, DR4 and DR5 gene promoters and clinical significance in the TSCC to evaluate association between methylation of DcR1, DcR2, DR4 and DR5 gene and Clinical Significance in tongue squamous cell carcinoma. METHODS: Methylation-specific PCR(MSP) was used to analyze the methylation of the promoters of TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) receptors in 45 TSCC cases. Real-Time PCR was used to detect the expression of the DcR1, DcR2, DR4 and DR5 gene. RESULTS: All the four genes (DcR1, DcR2, DR4 and DR5) showed different methylation of promoters in TSCC, while methylation of these promoters in paired adjacent normal tissues were almost undetectable. Patients with high methylation index were diagnosed at younger age when compared with the ones with low methylation index. DcR1 and DR4 hypermethylation was correlated significantly with patients' TNM stage. CONCLUSIONS: Methylation of DcR1, DcR2,DR4 and DR5 promoters are found in TSCC and may associate with its occurrence and development. Taking the reversibility of methylation into account,methylation is a potential targeted therapy of TSCC.

18.
Small ; : e1901517, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31165584

RESUMO

Mitochondria play a significant role in many cellular processes. Precise long-term tracking of mitochondrial status and behavior is very important for regulating cell fate and treating mitochondrial diseases. However, developing probes with photostability, long-term tracking capability, and tunable long-wavelength fluorescence has been a challenge in mitochondrial targeting. Carbon dots (CDs) as new fluorescent nanomaterials with low toxicity and high stability show increasing advantages in bioimaging. Herein, the mitochondria tracking CDs (MitoTCD) with intrinsic mitochondrial imaging capability and tunable long-wavelength fluorescence from green to red are synthesized where the lipophilic cation of rhodamine is served as the luminescent center of CDs. Due to the excellent photostability, superior fluorescence properties and favorable biocompatibility, these MitoTCD are successfully used for mitochondrial targeting imaging of HeLa cells in vitro and can be tracked as long as six passages, which is suitable for long-term cell imaging. Moreover, these MitoTCD can also be used for zebrafish imaging in vivo.

19.
Opt Express ; 27(12): 17007-17016, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31252918

RESUMO

High peak-to-average power ratio (PAPR) is an inherent defect in intensity modulation and direct detection (IM/DD) discrete-multitone (DMT) system, which will cause serious signal nonlinear distortion over fiber transmission. Single carrier-DMT (SC-DMT), which also refers to the discrete-Fourier-transform spread DMT (DFT-spread DMT), is a promising technology for DMT signal PAPR reduction, but higher computational complexity is required due to the additional DFT/IDFT operations in transceiver. In this paper, we experimentally compare the performance of SC-DMT and conventional DMT (CDMT) signal when the computational complexity of SC-DMT transceiver is lower than CDMT by reducing the FFT size in SC-DMT. The results show that the receiver sensitivity of 20 GHz 1024-point FFT based SC-DMT improves by 0.7 dB than 8192-point FFT based CDMT for both 120 Gb/s 64QAM-DMT and 140 Gb/s 128QAM-DMT signal transmission over 2-km single mode fiber (SMF) at the BER of 3.8 × 10-3 and 2.0 × 10-2, respectively. It is the first time to find that the SC-DMT with lower transceiver computational complexity outperforms CDMT. In addition, fast-Hartley-transform (FHT) technique is employed to replace FFT for further transceiver computational complexity reduction. The results give out that FHT-based SC-DMT shows the same BER performance with FFT-based SC-DMT, while the computational complexity of the transceiver can be reduced by half.

20.
Inorg Chem ; 58(12): 7997-8002, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31185556

RESUMO

Carbon-based metal or metal oxide nanocomposites have played an essential role in many fields. In this work, we reported that graphitic-carbon-layer-supported Cu-Cu2O nanocomposites (denoted as Cu-Cu2O-C) can be obtained via calcination of Cu-MOF-74, which shows superior activity for coupling of phenylacetylene to form 1,4-diphenylbutadiyne under visible light because of the synergistic action of the three components in the as-formed Cu-Cu2O-C. The catalyst is highly efficient and can be facilely recycled. Superior to the already reported phenylacetylene coupling systems, only visible light and a very low amount of copper (1.65 mol %) is required in our system. This study provides a promising strategy for visible-light-induced phenylacetylene coupling and highlights the great potential of using metal-organic frameworks as precursors to obtain carbon-supported metal/metal oxide nanocomposites for heterogeneous cooperative catalysis.

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