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1.
Inorg Chem ; 62(49): 20401-20411, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-38073496

ABSTRACT

Merging metal-organic frameworks (MOFs) and polyoxometalates (POMs) into heterogeneous heterojunction photocatalysts through in situ encapsulation is an effective approach to suppress the leachability of POMs and enhance their electron supply. The heterointerfacial connection in POMs@MOFs directly determines the performance of stability and charge separation, and the suited interaction between MOFs and POMs for POMs@MOFs heterojunctions photocatalyst is of vital importance. Here, a distinctive Keggin-type POM [(n-C4H9)N]10[SiW9Co3 (H2O)3O37]·17H2O (SiW9Co3) with near-total visible region absorption, narrow band gap of 2.23 eV, and powerful electron supply activity was prepared and tightly immobilized in the cavities of UiO-67-NH2 and UiO-68-NH2 to construct two Z-scheme heterojunctions SiW9Co3@UiO-67-NH2 and SiW9Co3@UiO-68-NH2, which were used for photocatalytic reduction of CO2 to CO. Their compositions, structures, and energy band features were fully characterized by a series of tests including XRD, FT-IR, SEM, XPS, UV-vis-DRS, UPS, and so forth. SiW9Co3@UiO-67-NH2 showed optimal photocatalytic performance with an excellent CO yield of 153.3 µmol-1·g-1·h-1 and a selectivity of 100%, which is 3.3-fold higher than that of SiW9Co3@UiO-68-NH2 and far superior to most reported POM-based heterojunctions. Comprehensive investigations with extensive photoelectric characterizations and microcalorimetric experiments demonstrated that the exceptional photocatalytic performances of SiW9Co3@UiO-67-NH2 could be attributed to the fact that (i) strong host-guest interactions were formed due to the well-matched dimensions between SiW9Co3 cluster and MOF cavity, which generated an intimate heterointerface to effectively accelerate interface electron transfer; (ii) the intimate heterointerface promoted SiW9Co3 to yield multielectron supply for efficient interfacial carrier neutralization owing to its donor-acceptor structure and narrow band gap. Additionally, the excellent durability of SiW9Co3@UiO-67-NH2 was also supported by the solidly locked SiW9Co3 and a stable MOF framework.

2.
Angew Chem Int Ed Engl ; 62(2): e202215110, 2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36370036

ABSTRACT

Metallic Zn is one of the most promising anodes, but its practical application has been hindered by dendritic growth and serious interfacial reactions in conventional electrolytes. Herein, ionic liquids are adopted to prepare intrinsically safe electrolytes via combining with TEP or TMP solvents. With this synergy effect, the blends of TEP/TMP with an IL fraction of ≈25 wt% are found to be promising electrolytes, with ionic conductivities comparable to those of standard phosphate-based electrolytes while electrochemical stabilities are considerably improved; over 1000 h at 2.0 mA cm-2 and ≈350 h at 5.0 mA cm-2 with a large areal capacity of 10 mAh cm-2 . The use of functionalized IL turns out to be a key factor in enhancing the Zn2+ transport due to the interaction of Zn2+ ions with IL-zincophilic sites resulting in reduced interfacial resistance between the electrodes and electrolyte upon cycling leading to spongy-like highly porous, homogeneous, and dendrite-free zinc as an anode material.

3.
Medicine (Baltimore) ; 97(50): e13402, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30557994

ABSTRACT

RATIONALE: Traumatic abdominal wall hernia (TAWH) is a rare form of hernia that is caused by disruption of the abdominal wall musculature and fascia. The diagnostic criteria and classification of TAWH are still unclear; furthermore, the ideal timing and method of surgical treatment are still unclear. Herein, we report a case of TAWH and describe the surgical approach used. PATIENT CONCERNS: A 71-year-old Han Chinese female presented for swelling in the right lower abdominal quadrant. The patient underwent exploratory laparotomy because of a car collision before 1 year ago. DIAGNOSIS: She was finally diagnosed with TAWH according to the abdominal computed tomography (CT) and surgery. INTERVENTIONS: She was performed with an open surgery to repair the TAWH. OUTCOMES: The patient was discharged without complications and showed no recurrence or complications during a follow-up period of 6 months. LESSONS: TAWH is a rare form of hernia that presents a diagnostic and therapeutic challenge. The appropriate timing and approach of surgical treatment for TAWH depend on a case-by-case basis. This case highlights that delayed selective surgery may be more suitable for stable patients.


Subject(s)
Abdominal Wall/abnormalities , Hernia, Abdominal/etiology , Seat Belts/adverse effects , Abdominal Injuries/complications , Abdominal Injuries/surgery , Abdominal Wall/surgery , Accidents, Traffic , Aged , Female , Hernia, Abdominal/surgery , Humans , Motor Vehicles , Tomography, X-Ray Computed/methods , Wounds and Injuries/complications , Wounds and Injuries/surgery , Wounds, Nonpenetrating/complications
4.
Materials (Basel) ; 11(6)2018 Jun 19.
Article in English | MEDLINE | ID: mdl-29921783

ABSTRACT

In order to achieve cermet-based solar absorber coatings with long-term thermal stability at high temperatures, a novel single-layer, multi-scale TiC-Ni/Mo cermet coating was first prepared using laser cladding technology in atmosphere. The results show that the optical properties of the cermet coatings using laser cladding were much better than the preplaced coating. In addition, the thermal stability of the optical properties for the laser cladding coating were excellent after annealing at 650 °C for 200 h. The solar absorptance and thermal emittance of multi-scale cermet coating were 85% and 4.7% at 650 °C. The results show that multi-scale cermet materials are more suitable for solar-selective absorbing coating. In addition, laser cladding is a new technology that can be used for the preparation of spectrally-selective coatings.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(3 Pt 2): 036302, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15524628

ABSTRACT

In this work, we develop a Reynolds stress model along the line of the approach presented by Commun. Nonlinear Sci. Numer. Simul. 9, 543 (2004)]], aiming to assess the role and contribution of the mean spin tensor in turbulence modeling. Here, the constitutive functional for the Reynolds stress depends on the mean spin tensor as well as the mean stretching tensor and its Jaumann derivative, the turbulent kinetic energy K , and the turbulent dissipation rate epsilon , which is at the complexity level of p=1,m=1 , and n=0 of a rate-type constitutive equation for the Reynolds stress proposed in the aforementioned paper. The explicit form for the Reynolds stress is obtained with recourse to the representation theorem and the theory of invariants developed in modern rational continuum mechanics, and, as an approximation, a nonlinear cubic K-epsilon model is worked out in which the model coefficients are analytically identified based on the experimental results of Tavoularis and Corrsin [J. Fluid Mech. 104, 311 (1981)]]. In addition, numerical results based on this model, in the forms of employing the Jaumann derivative and the Oldroyd derivative, respectively, for homogeneous turbulent shear flow and fully developed turbulent flow over a backward-facing step, are presented in comparison with those obtained based on a few previously proposed linear and nonlinear K-epsilon models, showing reasonably good agreement with the experimental results and the DNS data concerned and a better performance than the previously developed quadratic models.

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