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Positive magnetoresistance (PMR) and negative magnetoresistance (NMR) describe two opposite responses of resistance induced by a magnetic field. Materials with giant PMR are usually distinct from those with giant NMR due to different physical natures. Here, we report the unusual photomagnetoresistance in the van der Waals heterojunctions of WSe2/quasi-two-dimensional electron gas, showing the coexistence of giant PMR and giant NMR. The PMR and NMR reach 1,007.5% at -9 T and -93.5% at 2.2 T in a single device, respectively. The magnetoresistance spans over two orders of magnitude on inversion of field direction, implying a giant unidirectional magnetoresistance (UMR). By adjusting the thickness of the WSe2 layer, we achieve the maxima of PMR and NMR, which are 4,900,000% and -99.8%, respectively. The unique magnetooptical transport shows the unity of giant UMR, PMR, and NMR, referred to as giant bipolar unidirectional photomagnetoresistance. These features originate from strong out-of-plane spin splitting, magnetic field-enhanced recombination of photocarriers, and the Zeeman effect through our experimental and theoretical investigations. This work offers directions for high-performance light-tunable spintronic devices.NMR).
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Hypertension is a prominent contributor to vascular injury. Deubiquinatase has been implicated in the regulation of hypertension-induced vascular injury. In the present study we investigated the specific role of deubiquinatase YOD1 in hypertension-induced vascular injury. Vascular endothelial endothelial-mesenchymal transition (EndMT) was induced in male WT and YOD1-/- mice by administration of Ang II (1 µg/kg per minute) via osmotic pump for four weeks. We showed a significantly increased expression of YOD1 in mouse vascular endothelial cells upon Ang II stimulation. Knockout of YOD1 resulted in a notable reduction in EndMT in vascular endothelial cells of Ang II-treated mouse; a similar result was observed in Ang II-treated human umbilical vein endothelial cells (HUVECs). We then conducted LC-MS/MS and co-immunoprecipitation (Co-IP) analyses to verify the binding between YOD1 and EndMT-related proteins, and found that YOD1 directly bound to ß-catenin in HUVECs via its ovarian tumor-associated protease (OTU) domain, and histidine at 262 performing deubiquitination to maintain ß-catenin protein stability by removing the K48 ubiquitin chain from ß-catenin and preventing its proteasome degradation, thereby promoting EndMT of vascular endothelial cells. Oral administration of ß-catenin inhibitor MSAB (20 mg/kg, every other day for four weeks) eliminated the protective effect of YOD1 deletion on vascular endothelial injury. In conclusion, we demonstrate a new YOD1-ß-catenin axis in regulating Ang II-induced vascular endothelial injury and reveal YOD1 as a deubiquitinating enzyme for ß-catenin, suggesting that targeting YOD1 holds promise as a potential therapeutic strategy for treating ß-catenin-mediated vascular diseases.
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Angiotensina II , Células Endoteliais da Veia Umbilical Humana , Camundongos Endogâmicos C57BL , Camundongos Knockout , beta Catenina , Animais , beta Catenina/metabolismo , Humanos , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Masculino , Camundongos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Endotélio-MesênquimaRESUMO
Precise design of low-cost, efficient and definite electrocatalysts is the key to sustainable renewable energy. Herein, this work develops a targeted-anchored and subsequent spontaneous-redox strategy to synthesize nickel-iron layered double hydroxide (LDH) nanosheets anchored with monodispersed platinum (Pt) sites (Pt@LDH). Intermediate metal-organic frameworks (MOF)/LDH heterostructure not only provides numerous confine points to guarantee the stability of Pt sites, but also excites the spontaneous reduction for PtII . Electronic structure, charge transfer ability and reaction kinetics of Pt@LDH can be effectively facilitated by the monodispersed Pt moieties. As a result, the optimized Pt@LDH that with the 5% ultra-low content Pt exhibits the significant increment in electrochemical water splitting performance in alkaline media, which only afford low overpotentials of 58 mV at 10 mA cm-2 for hydrogen evolution reaction (HER) and 239 mV at 10 mA cm-2 for oxygen evolution reaction (OER), respectively. In a real device, Pt@LDH can drive an overall water-splitting at low cell voltage of 1.49 V at 10 mA cm-2 , which can be superior to most reported similar LDH-based catalysts. Moreover, the versatility of the method is extended to other MOF precursors and noble metals for the design of ultrathin LDH supported monodispersed noble metal electrocatalysts promoting research interest in material design.
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The switchable electric polarization is usually achieved in ferroelectric materials with noncentrosymmetric structures, which opens exciting opportunities for information storage and neuromorphic computing. In another polar system of p-n junction, there exists the electric polarization at the interface due to the Fermi level misalignment. However, the resultant built-in electric field is unavailable to manipulate, thus attracting less attention for memory devices. Here, we report the interfacial polarization hysteresis (IPH) in the vertical sidewall van der Waals heterojunctions of black phosphorus and quasi-two-dimensional electron gas on SrTiO_{3}. A nonvolatile switching of electric polarization can be achieved by reconstructing the space charge region (SCR) with long-lifetime nonequilibrium carriers. The resulting electric-field controllable IPH is experimentally verified by electric hysteresis, polarization oscillation, and pyroelectric effect. Further studies confirm the transition temperature of 340 K, beyond which the IPH vanishes. The second transition is revealed with the temperature dropping below 230 K, corresponding to the sharp improvement of IPH and the freezing of SCR reconstruction. This work offers new possibilities for exploring the memory phenomena in nonferroelectric p-n heterojunctions.
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Trichloroacetic acid (TCA), as a by-product of chlorination disinfection, is a highly carcinogenic chemical. Due to the widespread use of chlorination disinfection, it is critical to detect TCA in drinking water to decrease the incidence of disease. In this work, we developed an efficient TCA biosensor via electroenzymatic synergistic catalysis. The porous carbon nanobowls (PCNB) are prepared and wrapped by an amyloid like proteins formed by phase-transitioned lysozyme (PTL-PCNB), then, chloroperoxidase (CPO) is abounding to PTL-PCNB owing to its strong adhesion. The ionic liquid of 1-ethyl-3-methylimidazolium bromide (ILEMB) is co-immobilized on PTL-PCNB to from CPO-ILEMB@PTL-PCNB nanocomposite to assist the direct electron transfer (DET) of CPO. The PCNB plays two roles here. In addition, to increasing the conductivity, it serves as an ideal support for holding CPO; The CPO-ILEMB@PTL-PCNB nanocomposite modified electrode presents high efficiency for sensing TCA. Through electroenzymatic synergistic catalysis, a wide detection range of 33 µmol L-1 to 98 mmol L-1 can be achieved with a low detection limit of 5.9 µmol L-1, and high stability, selectivity as well as reproducibility, which ensures its potential practical applicability. This work provides a new platform for the electro-enzyme synergistic catalysis in one pot.
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Carbono , Cloreto Peroxidase , Ácido Tricloroacético , Reprodutibilidade dos Testes , Porosidade , CatáliseRESUMO
Stereo matching in binocular endoscopic scenarios is difficult due to the radiometric distortion caused by restricted light conditions. Traditional matching algorithms suffer from poor performance in challenging areas, while deep learning ones are limited by their generalizability and complexity. We introduce a non-deep learning cost volume generation method whose performance is close to a deep learning algorithm, but with far less computation. To deal with the radiometric distortion problem, the initial cost volume is constructed using two radiometric invariant cost metrics, the histogram of gradient angle and amplitude descriptors. Then we propose a new cross-scale propagation framework to improve the matching reliability in small homogenous regions without increasing the running time. The experimental results on the Middlebury Version 3 Benchmark show that the performance of the combination of our method and Local-Expansion, an optimization algorithm, ranks top among non-deep learning algorithms. Other quantitative experimental results on a surgical endoscopic dataset and our binocular endoscope show that the accuracy of the proposed algorithm is at the millimeter level which is comparable to the accuracy of deep learning algorithms. In addition, our method is 65 times faster than its deep learning counterpart in terms of cost volume generation.
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Six polycyclic aromatic hydrocarbons (PAHs) including naphthalene (Nap), fluorene (Flu), phenanthrene (Phe), fluoranthene (Fla), pyrene (Pyr), and chrysene (Chr) were detected in runoff from five athletic fields during three rainfall events. The event mean concentration (EMC) of ∑6PAHs ranged from 3.96 to 23.23 µg/L, which was much higher than the EMC in urban traffic area runoff. Except for Nap, the PAH concentrations followed in the order of artificial turf > badminton court > basketball court > plastic runway > optennis court. The surface characteristics of the athletic fields, such as the composition of materials and roughness, played an essential role in the release of PAHs. ∑6PAHs concentration during the 2nd rainfall event (July 22nd) was the highest among the three rainfall events, indicating that high rainfall intensity facilitated the PAHs release. PAHs during three rainfall events showed little first flush effect except for the artificial turf during the 2nd (22nd July) and 3rd (29th July) rainfall events. The first flush effect could be affected by rainfall characters, PAH properties, and surface characteristics of athletic fields. Ecological risk assessment showed that PAHs in runoff corresponded to moderate-to-high risk, while health risk assessment showed that PAHs could pose a potential carcinogenic danger to human health via dermal contact.
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Hidrocarbonetos Policíclicos Aromáticos , Esportes , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Medição de Risco , ChinaRESUMO
High storage capacity, high separation selectivity, and high structure stability are essential for an idea gas adsorbent. However, it is not easy to achieve all three at the same time, even for the promising metal-organic framework (MOF) adsorbents. We demonstrate herein that robust [Sc3O]-organic frameworks could be regulated by a micropore combination strategy for high-performance acetylene adsorption. Under the same solvent system with formic acid as a modulator, similar tritopic ligands extend [Sc3O(COO)6] trigonal-prismatic clusters to generate SNNU-5-Sc and SNNU-150-Sc adsorbents. Notably, the two Sc-MOFs can keep their architectures over 24 h in water at different pH values (2-12) or at 90 °C. Modulated by the linker symmetry, the final stacking metal-organic polyhedral cages produce open window sizes of about 10 Å for SNNU-5-Sc and 5 Å + 7 Å for SNNU-150-Sc. Due to such micropore combinations, SNNU-5-Sc exhibits a top-level C2H2 uptake of 211.2 cm3 g-1 (1 atm and 273 K) and SNNU-150-Sc shows high C2H2/CH4, C2H2/C2H4, and C2H2/CO2 selectivities of 80.65, 4.03, and 8.19, respectively, under ambient conditions. Dynamic breakthrough curves obtained on a fixed-bed column and grand canonical Monte Carlo (GCMC) simulations further support their prominent acetylene storage and purification performance. High framework stability, storage capacity, and separation selectivity make SNNU-5-Sc and SNNU-150-Sc ideal acetylene adsorbents in practical applications.
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Organic resistive memory (ORM) offers great promise for next-generation high-density multilevel-cell (MLC) data storage. However, the fine tuning of crystalline order among its active layer still remains challenging, which largely restricts ORM behavior. Here, an exceptional solid-state transition from disordered orientations to highly-uniform orientation within the ORM layer is facilely triggered via molecular strategic tailoring. Two diketopyrrolopyrrole-based small molecular analogues (NI1 TDPP and NI2 TDPP) are demonstrated to display different symmetry. The asymmetric NI1 TDPP shows an irregular solid-state texture, while the centro-symmetric NI2 TDPP conforms to an ordered out-of-plane single-crystalline pattern that aligns with the foremost charge transportation along the substrate normal, and exhibits excellent MLC memory characteristics. Moreover, this highly oriented pattern guarantees the large-area film uniformity, leading to the twofold increase in the yield of as-fabricated ORM devices. This study reveals that the solid-state crystalline nanostructural order of organic materials can be controlled by reasonable molecular design to actuate high-performance organic electronic circuits.
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Van der Waals (vdW) heterojunctions, based on two-dimensional (2D) materials, have great potential for the development of ecofriendly and high-efficiency nanodevices, which shows valuable applications as photovoltaic cells, photodetectors, etc. However, the coexistence of photoelectric conversion and storage in a single device has not been achieved until now. Here, we demonstrate a simple strategy to construct a vdW p-n junction between a WSe_{2} layer and quasi-2D electron gas. After an optical illumination, the device stores the light-generated carriers for up to seven days, and then releases a very large photocurrent of 2.9 mA with bias voltage applied in darkness; this is referred to as chargeable photoconductivity (CPC), which completely differs from any previously observed photoelectric phenomenon. In normal photoconductivity, the recombination of electron-hole pairs occurs at the end of their lifetime; in contrast, infinite-lifetime photocarriers can be generated and stored in CPC devices without recombination. The photoelectric conversion and storage are completely self-excited during the charging process. The ratio between currents in full- and empty-photocarrier states below the critical temperature reaches as high as 10^{9}, with an external quantum efficiency of 93.8% during optical charging. A theoretical model developed to explain the mechanism of this effect is in good agreement with the experimental data. This work paves a path toward the high-efficiency devices for photoelectric conversion and storage.
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Halloysite nanotube (HNT) is a natural bio-compatible and stable nanomaterial available in abundance at low-cost. In this work, HNT was modified by two strategies to make it suitable for supporting immobilization of chloroperoxidase (CPO). Firstly, Fe3O4 nanoparticles were deposited on HNT, so magnetic separation can be used instead of centrifugation. Then, the magnetic HNT was modified by 3-aminopropyltriethoxysilane (APTES), which can provide amine group on surface of HNT and meanwhile inhibit the agglomeration of magnetic HNT. Then, HNT-Fe3O4 -APTES was linked with branched polyethyleneimine (PEI) to provide more amino for binding with enzyme. The so-prepared CPO@HNT-Fe3O4-APTES-PEI showed enhanced enzyme loading, reusability, improved thermal stability and tolerance to organic solvents than free CPO. For example, after 10 repeated uses, CPO@HNT- Fe3O4-APTES-PEI can maintain 92.20% of its original activity compared with 65.12% of activity of CPO@HNT-APTES-PEI and 45.69% of activity of CPO@HNT. The kinetic parameters indicated the affinity and specificity of immobilized enzyme to substrate was increased. CPO@HNT-Fe3O4-APTES-PEI was very efficient when it was applied in the degradation of pesticides mesotrione in wastewater. The degradation efficiency can reach 90% within 20 min at range of 5-40 µmol·L-1. These results ensure the potential practical application of this bio-materials in wastewater treatment.
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Ascomicetos/enzimologia , Cloreto Peroxidase/química , Argila/química , Enzimas Imobilizadas/química , Óxido Ferroso-Férrico/química , Proteínas Fúngicas/química , Nanotubos/química , Praguicidas/química , Águas Residuárias/químicaRESUMO
The high storage capacity versus high selectivity trade-off barrier presents a daunting challenge to practical application as an acetylene (C2 H2 ) adsorbent. A structure-performance relationship screening for sixty-two high-performance metal-organic framework adsorbents reveals that a moderate pore size distribution around 5.0-7.5â Å is critical to fulfill this task. A precise pore space partition approach was involved to partition 1D hexagonal channels of typical MIL-88 architecture into finite segments with pore sizes varying from 4.5â Å (SNNU-26) to 6.4â Å (SNNU-27), 7.1â Å (SNNU-28), and 8.1â Å (SNNU-29). Coupled with bare tetrazole N sites (6 or 12 bare N sites within one cage) as high-density H-bonding acceptors for C2 H2 , the target MOFs offer a good combination of high C2 H2 /CO2 adsorption selectivity and high C2 H2 uptake capacity in addition to good stability. The optimized SNNU-27-Fe material demonstrates a C2 H2 uptake of 182.4â cm3 g-1 and an extraordinary C2 H2 /CO2 dynamic breakthrough time up to 91â min g-1 under ambient conditions.
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The construction of superstable metal-organic frameworks (MOFs) for selective gas uptake is urgently demanded but remains a great challenge. Herein, a unique bifunctional deformed [Ga3O(COO)6] inorganic secondary building unit (SBU) generated from the desymmetrical evolution of typical triangular prismatic trinuclear cluster was first introduced, which was extended by an isosceles triangular organic linker to produce a robust Ga-MOF (SNNU-63). Remarkably, SNNU-63 can stabilize in water at 25 °C for 96 h and at 80 °C for more than 24 h, which surpasses nearly all other Ga-MOFs. The combined effects of open metal sites and hydrophobic pore environment provided by deformed [Ga3O] SBUs render SNNU-63 with high C2H2 storage capacity and efficient C2H2 and natural gas purification performance. The ideal adsorbed solution theory calculation, column breakthrough tests, and grand canonical Monte Carlo simulations demonstrate that SNNU-63 is a potential material for addressing the challenge of C2H2/CO2 and C2H2/CH4 mixture separation under ambient conditions.
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The separation of a mixture of C2H2 and CO2 is a great challenge due to their similar molecular sizes and shapes. Al-based metal-organic frameworks (Al-MOFs) have great promise for gas separation applications due to their light weight, high stability, and low cost. However, the cultivation of suitable Al-MOF single crystals is extremely difficult and has limited their explorations up to now. Since In, Ga, and Al are all 3p-block metal elements, a systematic application of the periodic law to investigate 3p-MOFs will undoubtedly help in the understanding and development of worthy Al-MOF materials. Herein, we report the design of a robust 3p metal-organic framework platform (SNNU-150) and the systematic regulation of C2H2/CO2 separation by open 3p-block metal sites. X-ray single-crystal diffraction analysis reveals that SNNU-150 is a 3,6-connected 3D framework consisting of [M3O(COO)6] trinuclear secondary building units (SBUs) and tritopic nitrilotribenzoate (NTB) linkers. Small {[M3O(COO)6]4(NTB)6} tetrahedral cages and extra-large {[M3O(COO)6]10(NTB)14} polyhedral cages connect with each other to generate a hierarchically porous architecture. These 3p-MOFs present very high water, thermal, and chemical stability, especially for SNNU-150-Al, which can maintain its framework at 85 °C in water for 24 h and in a room-temperature environment for more than 30 days. IAST calculations, breakthrough experiments, and GCMC simulations all show that SNNU-150 MOFs have top-level C2H2/CO2 separation performance and follow the order Al-MOF > Ga-MOF > In-MOF.
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Both methane (CH4) and acetylene (C2H2) are important energy source and raw chemicals in many industrial processes. The development of an energy-efficient and environmentally friendly separation and purification strategy for CH4 and C2H2 is necessary. Ultramicroporous metal-organic framework (MOF) materials have shown great success in the separation and purification of small-molecule gases. Herein, the synergy effect of tritopic polytetrazolate and ditopic terephthalate ligands successfully generates a series of isoreticular ultramicroporous cadmium tetrazolate-carboxylate MOF materials (SNNU-13-16) with excellent CH4 and C2H2 purification performance. Except for the uncoordinated tetrazolate N atoms serving as Lewis base sites, the pore size and pore surface of MOFs are systematically engineered by regulating dicarboxylic acid ligands varying from OH-BDC (SNNU-13) to Br-BDC (SNNU-14) to NH2-BDC (SNNU-15) to 1,4-NDC (SNNU-16). Benefiting from the ultramicroporous character (3.8-5.9 Å), rich Lewis base N sites, and tunable pore environments, all of these ultramicroporous MOFs exhibit a prominent separation capacity for carbon dioxide (CO2) or C2 hydrocarbons from CH4 and C2H2. Remarkably, SNNU-16 built by 1,4-NDC shows the highest ideal adsorbed solution theory CO2/CH4, ethylene (C2H4)/CH4, and C2H2/CH4 separation selectivity values, which are higher than those of most famous MOFs with or without open metal sites. Dynamic breakthrough experiments show that SNNU-16 can also efficiently separate the C2H2/CO2 mixtures with a gas flow rate of 4 mL min-1 under 1 bar and 298 K. The breakthrough time (18 min g-1) surpasses most best-gas-separation MOFs and nearly all other metal azolate-carboxylate MOF materials under the same conditions. The above prominently CH4 and C2H2 purification abilities of SNNU-13-16 materials were further confirmed by the Grand Canonical Monte Carlo (GCMC) simulations.
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The detection of nitro compounds and removal of organic dyes remain urgent issues because they are poisonous to humans. Taking advantage of metal-organic framework (MOF) materials, we demonstrate herein an indium-organic framework (InOF) exhibiting sensitive fluorescence sensing of nitro compounds, prominent dye capture, and excellent photodegradation of dyes. By using 4,4',4â³-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB), an amino-functionalized BTB-like linker, the 3D SNNU-110 structure ({[In3OCl(H2O)2(TATAB)2]}n) is formed. SNNU-110 shows a 3,6-connected 3,6T22 topology with TATAB and [In3O(CO2)6] tricapped trigonal-prismatic clusters as 3- and 6-connected nodes. Thanks to the fluorescence properties and amine recognition sites of TATAB, SNNU-110 exhibits excellent performance of fluorescence quenching for six electron-deficient nitroaromatics. The intercrossing 1D channels in SNNU-110 formed from the a- and b-axis directions with dimensions of about 18 Å × 11 Å can capture diverse cationic, anionic, or neutral dyes effectively. What is more, the existence of an inorganic [In3O] cluster enable SNNU-110 to be a good photocatalyst. Upon irradiation with a 300 W xenon lamp, SNNU-110 shows outstanding photocatalytic activity toward rhodamine B (RhB) and methylene blue (MB), and there was almost no degradation. The catalytic activity can retain about 94.6% (RhB) and 93.1% (MB), respectively. Overall, SNNU-110 fully demonstrates the power of multicomponent MOFs, which provide a feasible route for the design of functional materials toward to pollutant identification and removal applications.
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Evaluating the effect of ligand substitution on metal ions and/or clusters during the MOF growth process is conducive to rational design of isoreticular MOFs with improved performance. Through topological direction and ligand substitution strategy, we herein constructed two Sc-soc-MOFs (Sc-EBTC and Sc-ABTC) based on two similar rectangular-planar diisophthalate ligands, linear-shaped H4EBTC (1,1'-ethynebenzene-3,3',5,5'-tetracarboxylic acid) and zigzag-shaped H4ABTC (3,3',5,5'-azobenzenetetracarboxylic acid), under solvothermal conditions with formic acid as a modulator. {Sc[(Sc3O)(H2O)3]3(EBTC)6} (Sc-EBTC) possesses two distinct clusters as SBUs, trinuclear [Sc3O(CO2)6] (SBU1) and mononuclear cluster [ScO6] (SBU2), which maintain the soc-topology except for the mononuclear [ScO6] instead of the corresponding trinuclear [Sc3O(CO2)6] in Sc-ABTC ({(Sc3O)(H2O)3(ABTC)1.5(NO3)}). Notably, Sc-EBTC represents a rare soc-MOF with two distinct clusters as SBUs. Due to similar pore spaces, the two Sc-soc-MOF materials both exhibit enhanced and comparable gas sorption and selectivity performances. Specially, their remarkable C2H2, C2H4, and CO2 storage capacity along with prominent CO2/CH4 and C2-hydrocarbons/CH4 separations indicate that these Sc-soc-MOFs are promising adsorbents for natural gas purification under ambient conditions.
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A multitude of industrial processes are catalyzed by two or more enzymes working together in a cascade way. However, designing efficient enzymatic cascade reactions is still a challenge. In this work, a TiO2 thin film with mesoporous pores was prepared and used as carrier for co-immobilization of chloroperoxidase (CPO) and glucose peroxidase (GOx). By adjusting the dosage of hexadecyltrimethylammonium bromide (CTAB) and the ratio of the two enzymes, CPO and GOx were well distributed and positional orientated to their own appropriate pores to form an ordered "occupation" based on a "feet in right shoes" effect. Moreover, when the pore size was controlled around 12 nm, the enzymes aggregation was inhibited so as to avoid the decrease of activity of enzyme; The catalytic performance of TiO2-GOx and CPO composites was evaluated by the application of decolorization of Orange G dye in a cascaded manner. The oxidant H2O2 needed by CPO is generated in situ through glucose oxidation by GOx. Upon co-immobilization of CPO and GOx on the same carrier, a large increase in the initial catalytic efficiency was detected when compared to an equimolar mixture of the free enzymes, which was four times greater. Moreover, the affinity of the enzyme toward substrate binding was improved according to the kinetic assay. The thermal stability of TiO2-GOx and CPO composites were greatly improved than free enzymes. The TiO2-GOx and CPO composites can be easily separated from the reaction media which facilitate its recycle use.
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Compostos Azo/química , Cloreto Peroxidase/química , Enzimas Imobilizadas/química , Membranas Artificiais , Peroxidases/química , Titânio/química , Oxirredução , PorosidadeRESUMO
A strategy called ultramicroporous building unit (UBU) is introduced. It allows the creation of hierarchical bi-porous features that work in tandem to enhance gas uptake capacity and separation. Smaller pores from UBUs promote selectivity, while larger inter-UBU packing pores increase uptake capacity. The effectiveness of this UBU strategy is shown with a cobalt MOF (denoted SNNU-45) in which octahedral cages with 4.5â Å pore size serve as UBUs. The C2 H2 uptake capacity at 1â atm reaches 193.0â cm3 g-1 (8.6â mmol g-1 ) at 273â K and 134.0â cm3 g-1 (6.0â mmol g-1 ) at 298â K. Such high uptake capacity is accompanied by a high C2 H2 /CO2 selectivity of up to 8.5 at 298â K. Dynamic breakthrough studies at room temperature and 1 atm show a C2 H2 /CO2 breakthrough time up to 79â min g-1 , among top-performing MOFs. Grand canonical Monte Carlo simulations agree that ultrahigh C2 H2 /CO2 selectivity is mainly from UBU ultramicropores, while packing pores promote C2 H2 uptake capacity.