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1.
Small ; 20(11): e2305905, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37926774

RESUMO

To overcome the low efficiency of overall water splitting, highly effective and stable catalysts are in urgent need, especially for the anode oxygen evolution reaction (OER). In this case, nickel selenides appear as good candidates to catalyze OER and other substitutable anodic reactions due to their high electronic conductivity and easily tunable electronic structure to meet the optimized adsorption ability. Herein, an interesting phase transition from the hexagonal phase of NiSe (H-NiSe) to the rhombohedral phase of NiSe (R-NiSe) induced by the doping of cobalt atoms is reported. The five-coordinated R-NiSe is found to grow adjacent to the six-coordinated H-NiSe, resulting in the formation of the H-NiSe/R-NiSe heterostructure. Further characterizations and calculations prove the reduced splitting energy for R-NiSe and thus the less occupancy in the t2g orbits, which can facilitate the electron transfer process. As a result, the Co2 -NiSe/NF shows a satisfying catalytic performance toward OER, hydrogen evolution reaction, and (hybrid) overall water splitting. This work proves that trace amounts of Co doping can induce the phase transition from H-NiSe to R-NiSe. The formation of less-coordinated species can reduce the t2g occupancy and thus enhance the catalytic performance, which might guide rational material design.

2.
Inorg Chem ; 63(22): 10288-10295, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38780405

RESUMO

Currently, oxychalcogenides with mixed-anion groups that integrate the property advantages of oxides (wide optical band gap) and chalcogenides [strong second harmonic generation (SHG) response] through chemical substitution engineering have attracted widespread interest and are considered to be important candidates for infrared (IR) nonlinear optical (NLO) materials. Herein, the first Hg-based oxychalcogenide Sr2HgGe2OS6 with mixed anion [GeOS3] units has been successfully synthesized through a spontaneous crystallization method, which exhibits a favorable balance between the strong SHG response (0.7 × AgGaS2) and large optical band gap (2.9 eV). In addition, Sr2HgGe2OS6 shows high laser-induced damage threshold (LIDT, 2.1 × AgGaS2) as well as phase-matching (PM) performance. Theoretical calculations indicate that the Sr2HgGe2OS6 encompasses large birefringence of 0.128@2090 nm (3.3 × AgGaS2) and its SHG density mainly comes from [HgS4] tetrahedra and [GeOS3] units. This work not only demonstrates that Sr2HgGe2OS6 is a promising IR NLO material but also provides new ideas for the exploration of Hg-based oxychalcogenide IR NLO materials.

3.
Small ; 19(48): e2303015, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37582643

RESUMO

Preparing MoS2 -based materials with reasonable structure and catalytic activity to enhance the sluggish kinetics of lithium polysulfides (LiPSs) conversion is of great significance for Li-S batteries (LSBs) but still remain a challenge. Hence, hollow nanotubes composed of N-doped ultrathin MoS2 nanosheets (N-MoS2 NHTs) are fabricated as efficient S hosts for LSBs by using CdS nanorods as a sacrifice template. Characterization and theoretical results show that the template effectively inhibits the excessive growth of MoS2 sheets, and N doping expands the interlayer spacing and modulates the electronic structure, thus accelerating the mass/electron transfer and enhancing the LiPSs adsorption and transformation. Benefiting from the merits, the N-MoS2 NHTs@S cathode exhibits an excellent initial capacity of 887.8 mAh g-1 and stable cycling performances with capacity fading of only 0.0436% per cycle at 1.0 C (500 cycles). Moreover, even at high S loading that of 7.5 mg cm-2 , the N-MoS2 NHTs@S cathode also presents initial excellent areal capacity of 7.80 mAh cm-2 at 0.2 C. This study offers feasible guidance for designing advanced MoS2 -based cathode materials in LSBs.

4.
Inorg Chem ; 62(8): 3609-3615, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36795025

RESUMO

Enthusiasm for the exploration of nonlinear alkali metal borates remains high. Focusing on the Li-B-O-X (X = Cl and Br) system, two examples of noncentrosymmetric borates, Li3B8O13Cl and Li3B8O13Br, were obtained using a high-temperature solution method under vacuum conditions. Structurally, the Li3B8O13X crystals exhibit two independent alternately arranged three-dimensional B-O network structures formed by the basic building block unit B8O16. The performance measurements demonstrate their short ultraviolet cutoff edges. The theoretical calculation indicates that the BO3 units dominate the contribution to their large optical anisotropy with the birefringence, 0.094 and 0.088@1064 nm for Li3B8O13Cl and Li3B8O13Br, respectively.

5.
Inorg Chem ; 62(5): 2480-2488, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36697214

RESUMO

Nonlinear optical (NLO) crystals, being the primary medium for laser wavelength conversion, are crucial in all-solid-state lasers. Borophosphates offer more structural varieties than pure borates and phosphates, and they have become popular as NLO crystal candidates. Through spontaneous crystallization, we acquired a noncentrosymmetric alkali metal borophosphate crystal material, K2Na3B2P3O13 (KNBPO). KNBPO crystallizes in the orthorhombic Cmc21 space group with the following unit cell parameters: a = 13.9238(18) Å, b = 6.7673(8) Å, c = 12.1298(15) Å, and Z = 4, and its structure is characterized by a fundamental building unit 1∞ [B2P3O13] chain structure made up of bridging oxygen linkages between BO4 and PO4 tetrahedra. KNBPO has a short ultraviolet (UV) cut-off edge (<186 nm), a congruent melting characteristic, good thermal stability, and a moderate second harmonic generation response roughly 0.42 times that of KH2PO4. Theoretical calculations reveal that the optical properties of the compound mainly originate from BO4 and PO4 units. Due to the short UV cut-off edge, KNBPO can be used as a potential NLO material in the UV and even deep UV regions, and it enhances the structural variety of borophosphates, which has a reference value for scholars investigating similar materials.

6.
Chemphyschem ; 23(15): e202200205, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35524646

RESUMO

In this study, a series of tetrafluoroborates with non-π-conjugated [BF4 ] tetrahedra are investigated systematically by first-principles calculations. Theoretical studies demonstrate that tetrafluoroborates with alkali and/or alkaline-earth metals are more favorable for deep-ultraviolet transmission and are comparable to the classical deep-ultraviolet (deep-UV) material, MgF2 . Furthermore, bandgap decrease with the increasing of ionic radii in alkali and/or alkaline-earth metals. Introducing highly polarizable cations with d10 -configuration or cations with lone pair electrons into the structure will decrease the bandgaps. The birefringence and second harmonic generation effects are not large enough in tetrafluoroborates because polarizability anisotropy and hyperpolarizability in non-π-conjugated [BF4 ] tetrahedra are much smaller than those in π-conjugated groups. However, the second harmonic generation effect for [BF4 ] tetrahedra has a higher contribution in comparison with that due to birefringence. To effectively synthesize the borate fluorides or fluorooxoborates in the deep-UV region, raw materials with B-F bonds are preferred.

7.
Inorg Chem ; 61(48): 19302-19308, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36397200

RESUMO

In this paper, a revised structure determination of an already known compound CsNbOB2O5 with new structural insights was performed and the detailed characterization of its optical properties was reported for the first time. CsNbOB2O5 was synthesized by spontaneous crystallization. It crystallizes in the Pmn21 space group, and the unit lattice parameters are a = 7.5220(7) Å, b = 3.9881(4) Å, c = 9.7167(9) Å, and Z = 2. In the structure of CsNbOB2O5, a [NbO5] square pyramid and [B2O5] unit are linked to constitute an infinitely extended two-dimensional ∞2[NbOB2O5] layer via sharing oxygen atoms. Between these two-dimensional layers, there are no covalent bonds perpendicular to their planes based on Mulliken bond order analysis. CsNbOB2O5 has a wide band gap (4.52 eV) and a large second-harmonic-generation (SHG) response (1.2 × KDP) and demonstrates type-I phase-matchable behavior. First-principles simulations reveal that the birefringence is approximately 0.10. Moreover, SHG-weighted charge density analysis shows that the primary source of the nonlinearity of the title compound is the distorted NbO5 square pyramids.

8.
Diabetes Obes Metab ; 23(3): 742-753, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33269505

RESUMO

AIM: To assess the outcomes of metabolic surgery in overweight and obese patients in Asia with type 2 diabetes (T2D). MATERIALS AND METHODS: The treatment outcomes of 1999 patients from the Asian Diabetes Surgery Summit database were analysed. The changes in treatment effects across time were assessed with respect to the surgical procedures performed by using generalized estimating equations. RESULTS: The most commonly performed procedure was the single-anastomosis gastric bypass (32.6%). Weight (from 106.2 ± 25.1 to 77.9 ± 18.8 kg), body mass index (BMI; from 38.7 ± 7.9 to 28.5 ± 5.9 kg/m2 ), blood sugar (from 9.3 ± 4.1 to 5.7 ± 1.8 mmol/L) and HbA1c (from 8.4% ± 1.8% to 6.0% ± 1.1%) significantly improved from baseline to 1 year (P < .001) and remained stable at 5 years (weight, 86.3 ± 23.3 kg; BMI, 31.7 ± 7.9 kg/m2 ; blood sugar, 5.8 ± 1.8 mmol/L, and HbA1c, 6.4% ± 1.2%; all P < .001 vs. baseline). Blood pressure and most lipid disorders also improved significantly. Of the treatment procedures, single-anastomosis gastric bypass had the most satisfactory outcomes with statistical significance for most disorders, whereas adjustable gastric banding displayed the least satisfactory outcomes. CONCLUSIONS: Metabolic surgery remarkably improved body weight, T2D and other metabolic disorders in Asian patients. However, the efficacy of individual procedures varied substantially.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Derivação Gástrica , Obesidade Mórbida , Ásia/epidemiologia , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/cirurgia , Humanos , Obesidade/complicações , Obesidade/cirurgia , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Resultado do Tratamento
9.
Inorg Chem ; 59(4): 2519-2526, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31999111

RESUMO

A new family of Na3AgSnQ4 (Q = S or Se) and Na3MIIInS4 (MII = Cd or Hg) was successfully synthesized in vacuum-sealed silica tubes for the first time. They exhibit similar isolated one-dimensional (1D) double chains {[AgSnQ4]n vs [(MII/In)S4]n} in their structures. After the detailed survey on the Inorganic Crystal Structure Database, title compounds can be described as the first discovered examples exhibiting novel 1D double-chain configurations in the known 171 (MIB and MIVA) or 48 (MIIB and MIIIA) element-based quaternary A-MIB/MIIB-MIVA/MIIIA-Q chalcogenides. In addition, their dimensionalities on the mode of connection between two anionic groups are closely related to the empirical A/(IB+IVA) and A/(IIB+IIIA) in the unit cell or the (IB+IVA)/Q and (IIB+IIIA)/Q ratios, which may produce a good way to predict and design new chalcogenides with low-dimensional structures. Photoluminescence measurement shows that Na3CdGaS4 and Na3CdInS4 display strong red emission (648 and 647 nm) at room temperature that also agrees well with the change in color from yellow to red under the irradiation of an ultraviolet lamp. Moreover, all of the title crystals exhibit a large optical anisotropy (Δn@1064 nm ≥ 0.13), and isolated 1D double chains may produce a huge effect to enhance optical anisotropy based on the first-principles calculations, which also gives us a feasible way to design new birefringent materials.

10.
Angew Chem Int Ed Engl ; 59(40): 17648-17656, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32558985

RESUMO

Two new pyrophosphates nonlinear optical (NLO) materials, Rb3 PbBi(P2 O7 )2 (I) and Cs3 PbBi(P2 O7 )2 (II), were successfully designed and synthesized. Both compounds exhibit large NLO effects and birefringences. Material I presents the scarce case of possessing the coexistence of large birefringence (0.031 at 1064 nm and 0.037 at 532 nm) and second harmonic generation (SHG) response (2.8× potassium dihydrogen phosphate (KDP)) in ultraviolet NLO phosphates and its SHG is the largest in the phase-matching (PM) pyrophosphates. Both I and II have three-dimensional (3D) crystal structures composed of corner-shared RbO12 (CsO11 ), RbO10 (CsO10 ), BiO6 , PbO7 (PbO6 ) and P2 O7 groups, in which P2 O7 and PbO7 (PbO6 ) units form an alveolate [PbPO]∞ skeleton frame. Theoretical calculations reveal that the P-O, Bi-O and Pb-O units are mainly responsible for the moderate birefringence and large SHG efficiency of I.

11.
J Vasc Surg ; 67(4): 1217-1226, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29103931

RESUMO

OBJECTIVE: The urgency with which salvage of thrombosed vascular accesses for dialysis should be attempted remains unknown. We examined the effect of a timely thrombectomy approach on vascular access outcomes for dialysis. METHODS: A before-and-after study was conducted with patients on hemodialysis who had undergone endovascular thrombectomy. A timely thrombectomy initiative (ie, salvage within 24 hours of thrombosis diagnosis) was started in July 2015 at our institution. Data about thrombectomy procedures, performed within 1 year before and after the initiative was introduced, were abstracted from an electronic database. Immediate outcomes and patency outcomes were compared between the preinitiative (control) and postinitiative (intervention) groups. RESULTS: During the study period, 329 patients were enrolled, including 165 cases before and 164 cases after the initiative. The intervention group had more thrombectomy procedures performed within 24 hours (93% vs 55%; P < .01) and within 48 hours (97% vs 79%; P < .01) than the control group. No between-group differences in procedural success or clinical success rates were found. At 3 months, the intervention group had a higher postintervention primary patency rate than the control group, although this did not reach statistical significance (58% vs 48%; P = .06). After stratification into native or graft accesses, the patency benefit was observed in the native access group (68% vs 50%; P = .03) but not in the graft access group (50% vs 46%; P = .65). After adjusting for potential confounders, timely thrombectomy remained an independent predictor of postintervention primary patency (hazard ratio, 0.449; 95% confidence interval, 0.224-0.900; P = .02) for native dialysis accesses. CONCLUSIONS: Our results suggest that a timely thrombectomy approach, in which salvage is attempted within 24 hours of thrombosis diagnosis, improves postintervention primary patency of native but not graft accesses for dialysis.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/terapia , Diálise Renal , Trombectomia , Trombose/terapia , Tempo para o Tratamento , Grau de Desobstrução Vascular , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/métodos , Derivação Arteriovenosa Cirúrgica/normas , Implante de Prótese Vascular/métodos , Implante de Prótese Vascular/normas , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Avaliação de Programas e Projetos de Saúde , Modelos de Riscos Proporcionais , Melhoria de Qualidade , Indicadores de Qualidade em Assistência à Saúde , Estudos Retrospectivos , Fatores de Risco , Terapia de Salvação , Trombectomia/efeitos adversos , Trombectomia/normas , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo , Tempo para o Tratamento/normas , Resultado do Tratamento
12.
Inorg Chem ; 57(17): 10568-10575, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30124046

RESUMO

Two new isotypic diphosphates, RbLiZnP2O7 (RLZP) and CsLiZnP2O7 (CLZP), have been synthesized by a high-temperature solid-phase method. They both crystallize in the Pnma space group (No. 62) and have similar crystal configurations. ALiZnP2O7 (A = Rb, Cs) consists of a [Li2Zn2P4O20]14- anionic skeleton, which is composed of Li/ZnO4 tetrahedral and diphosphate groups, and the Rb or Cs atoms are located in the large hole. In this paper, we discuss the structures of the title compounds and isonomic AA'ZnP2O7 (A = alkali metal); it is found that the ionic radii of the cations and bond angles have an effect on the symmetry of the compounds. By analysis, we found that the M/P values have some effect on the dimensionality of the anionic groups in phosphates containing P2O7 groups. Thermal and spectral analyses are carried out on the title compounds. Besides that mentioned above, we also studied the relationship between the electronic structures and optical properties by theoretical calculations.

13.
Inorg Chem ; 56(10): 5636-5645, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28447784

RESUMO

Replacing hydroxyl anions OH¯ by fluorine anions F¯ in borates can cause the blue shift of the UV cutoff edge and also exhibits apparent differences in nonlinear optical (NLO) properties. To clarify the intrinsic difference between OH¯ anions and F¯ anions, several typical borates with different types of cations (p-cations with lone-pair electrons, trivalent rare-earth, and alkaline earth metals) have been studied. The theoretical studies reveal that the blue shift in the band gap of borates with fluorine as compared to those with hydroxyl can be assumed to be the result of weaker interaction of the cation-fluoride (La/Bi/B-F) bonds compared to that of the cation-oxygen and hydroxyl bonds. NLO properties are found to have the order of BiB2O4F > BiB2O4(OH)> LaB2O4F ≈ LaB2O4(OH). The large difference can be attributed mainly to the stereochemical activity of the lone pair (SCALP) effect of the Bi cations and the special BO3F with strong anisotropy as compared to the BO4 group. The energy spanning of F-2p orbitals is more extended in BiB2O4F as compared to LaB2O4F, Sr3B6O11F2, and Ba3B6O11F2 due to the bonding of Bi/B-F, which indicates F-2p orbitals have more chance to overlap with surrounding atoms and enhance the polarizability in all systems. Moreover, the degree of SCALP of the Bi cations is apparently activated by the introduction of the F¯ anions, which causes an obvious enhancement in NLO properties in bismuth borates with F¯. These investigations will help us to classify the solid-state chemistry of F¯ and OH¯ anions in borate systems with different types of metal cations.

14.
Microsurgery ; 37(3): 197-205, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26175309

RESUMO

BACKGROUND: Lymph node flap transfer popularity for treatment of extremity lymphedema is increasing quickly. Multiple flap donor sites were described in search of the optimal one. We describe the technique and outcomes of a laparoscopically harvested right gastroepiploic lymph node flap for treatment of extremity lymphedema. METHODS: From January 2012 to January 2013, 10 consecutive female patients, average age 54.8 years, with International Society of Lymphology stage II-III extremity lymphedema refractory to conservative management were included. Five patients had upper limb breast cancer-related lymphedema and five patients had lower limb pelvic cancer-related lymphedema. All patients underwent laparoscopic harvest of the right gastroepiploic lymph node flap, transferred to the wrist and ankle as recipient sites. Flaps were covered with a small skin graft taken from the thigh. Perioperative assessment included physical exam, photography, circumference measurements, CT scans, lymphoscintigraphy, and Lymphedema Quality of Life (LYMQOL) questionnaire. Clinical and CT evaluation of donor-site morbidity were performed. RESULTS: The flap survival rate was 100%, with a mean harvest time of 32 minutes and total operating time of 164 minutes. One case required regrafting for skin graft loss. The mean limb reduction rate was 39.5% at a mean follow-up of 14.7 months. Perioperative lymphoscintigraphy demonstrated transferred lymph node viability and lymphatic transport improvement. LYMQOL showed a 2.6-fold quality-of-life improvement (P < 0.01). No donor-site morbidity was encountered. CONCLUSIONS: The use of the laparoscopically harvested right gastroepiploic lymph node flap may be a safe technique that improves limb measurements and quality of life in extremity lymphedema patients. © 2015 Wiley Periodicals, Inc. Microsurgery 37:197-205, 2017.


Assuntos
Laparoscopia/métodos , Linfonodos/transplante , Linfedema/diagnóstico por imagem , Linfedema/cirurgia , Qualidade de Vida , Adulto , Idoso , Estudos de Coortes , Feminino , Retalhos de Tecido Biológico/irrigação sanguínea , Retalhos de Tecido Biológico/transplante , Artéria Gastroepiploica/cirurgia , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Extremidade Inferior/fisiopatologia , Extremidade Inferior/cirurgia , Linfonodos/cirurgia , Linfocintigrafia/métodos , Microcirurgia/métodos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Extremidade Superior/fisiopatologia , Extremidade Superior/cirurgia
15.
Inorg Chem ; 54(4): 1556-62, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25642733

RESUMO

Pure BaMgSiO4:Eu(2+) phosphor, prepared by a solid state reaction method under N2 atmosphere, exhibited a strong green emission at 500 nm and a weak emission at 405 nm. Heat treatment under NH3 atmosphere causes changes in the PL intensity: the green emission at 500 nm gradually decreases and completely disappears after heat treatment for 3 h, whereas a new blue emission peak, centered at 445 nm, appears and becomes very strong. The results of the analyses with electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS) spectroscopy suggest that the heat treatment causes the generation of a large amount of oxygen vacancies. This resulted in the aforementioned color changes of the BaMgSiO4:Eu phosphor, which are confirmed by the results of DFT+U calculations. In particular, these calculations showed that Eu prefers to occupy Ba(3) sites, which are six coordinated to oxygen atoms. The emission at 500 nm was attributed to the 4f-5d transition energy of Eu in Ba(3) site, calculated as 2.54 eV. It was also shown that Eu 4f energy level decreases when oxygen is removed from the oxygen position adjacent to Eu, which results in a larger Eu 4f-5d transition energy and shorter wavelengths of emission peaks.

16.
Phys Chem Chem Phys ; 17(7): 5338-44, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25609419

RESUMO

A novel mechanism for the nonlinear optical (NLO) effects of vanadium borate crystals, Na3VO2B6O11 (NVB), with distorted VO4 groups was investigated. A comprehensive analysis of the structure-property relationship was performed by combining the experimental measurements, the electronic structures calculations, the SHG-weighted electron density and the real-space atom-contribution analysis to yield the linear and nonlinear optical properties. The contribution of a (VO4)(3-) anionic group to the second harmonic generation (SHG) response was more pronounced than that of the (BO3)(3-) anionic group, which plays a virtual role in the SHG effects in NVB. The anionic (BO3)(3-) groups make dominant contributions to the birefringence, whereas the contribution of the V(5+) cations to these linear optical effects is negligible.

17.
Dalton Trans ; 53(7): 3377-3385, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38264854

RESUMO

Phosphates, whose obvious disadvantage is the relatively small birefringence, can be overcome by the introduction of post-transition metal cations containing stereochemically active lone-pair electrons. In this paper, two new compounds were successfully explored in the A-Sb-P-O system, i.e. Cs2Sb3O(PO4)3 (CsSbPO) and (NH4)2Sb4O2(H2O)(PO4)2[PO3(OH)]2 (NH4SbPOH). Transmission spectra show that CsSbPO has a surprising transmission range with a UV cutoff edge of 213 nm. First-principles calculations show that both compounds have a wide band gap (5.02 eV for CsSbPO and 5.30 eV for NH4SbPOH) and enlarged birefringence (Δn = 0.034@1064 nm for CsSbPO and Δn = 0.045@1064 nm for NH4SbPOH). The results of real-space atom-cutting investigations show that the distorted [SbOx] polyhedra originating from the asymmetric lone pair electrons give the main contribution to the total birefringence and overcome the disadvantage of small birefringence of phosphates but maintain wide transition windows.

18.
Int J Surg ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770830

RESUMO

BACKGROUND: Metabolic bariatric surgery offers enduring weight reduction and alleviation of obesity-related comorbidities, including dyslipidemia, diabetes, hypertension, and major adverse cardiovascular events (MACE). Long-term data on one-anastomosis gastric bypass (OAGB) and single-anastomosis duodenal-jejunal bypass with sleeve gastrectomy (SADJB-SG) is lacking, necessitating this investigation. MATERIALS AND METHODS: In this multicenter prospectively-collected retrospective observational study, 830 adult Taiwanese patients (682 OAGB, 148 SADJB-SG) who underwent surgery from January 1, 2011, to December 31, 2017, were initially identified. Following protocol, 224 patients (177 OAGB, 47 SADJB-SG) with complete follow-up data at various intervals up to three years after surgery were included in the final analysis. The study's primary focus is to evaluate the long-term safety, efficacy, and durability of OAGB and SADJB-SG in promoting weight loss and diabetes remission. Additionally, changes in 10-year and lifetime risks of MACE before and 3-year after surgery are assessed using Taiwan MACE risk prediction model and the China-PAR project model. RESULTS: SADJB-SG patients exhibit higher diabetes prevalence, lower body mass index, and more severe diabetes compared to OAGB. Both groups demonstrate significant improvements in body mass index, diabetes, hypertension, and dyslipidemia three years after surgery, with the most substantial improvements occurring in the second year. The Taiwan MACE risk model reveals a significant reduction in 10-year MACE and stroke risks for both groups. The China-PAR project model indicates a synchronized reduction in atherosclerotic cardiovascular disease 10-year and lifetime risk in both OAGB and SADJB-SG groups. CONCLUSIONS: OAGB and SADJB-SG exhibit sustained improvements in weight reduction and obesity-related comorbidities over three years after surgery. Notably, both procedures contribute to a substantial reduction in 10-year MACE, stroke, and atherosclerotic cardiovascular disease risks. These findings underscore the efficacy of OAGB and SADJB-SG in the context of metabolic bariatric surgery.

19.
Adv Mater ; 36(23): e2312618, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38439598

RESUMO

Spin engineering is a promising way to modulate the interaction between the metal d-orbital and the intermediates and thus enhance the catalytic kinetics. Herein, an innovative strategy is reported to modulate the spin state of Co by regulating its coordinating environment. o-c-CoSe2-Ni is prepared as pre-catalyst, then in situ electrochemical impedance spectroscopy (EIS) and in situ Raman spectroscopy are employed to prove phase transition, and CoOOH/Co3O4 is formed on the surface as active sites. In hybrid water electrolysis, the voltage has a negative shift, and in zinc-ethanol-air battery, the charging voltage is lowered and the cycling stability is greatly increased. Coordinated atom substitution and crystalline symmetry change are combined to regulate the absorption ability of reaction intermediates with balanced optimal adsorption. Coordinated atom substitution weakens the adsorption while the crystalline symmetry change strengthens the adsorption. Importantly, the tetrahedral sites are introduced by Ni doping which enables the co-existence of four-coordinated sites and six-coordination sites in o-c-CoSe2-Ni. The dz2 + dx2-y2 orbital occupancy decreases after the atomic substitution, while increases after replacing the CoSe6-Oh field with CoSe6-Oh/CoSe4-Td. This work explores a new direction for the preparation of efficient catalysts for water electrolysis and innovative zinc-ethanol-air battery.

20.
Dalton Trans ; 52(11): 3344-3350, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36808209

RESUMO

Rare earth borates, a subset of the essential nonlinear optical (NLO) materials, have sparked a significant amount of attention in recent years. In self-fluxing systems, two non-centrosymmetric scandium borates with classical B5O10 groups, namely Rb7SrSc2B15O30 (I) and Rb7CaSc2B15O30 (II), were successfully discovered. Both I and II exhibit a short ultraviolet (UV) cutoff edge (<200 nm) and appropriate second-harmonic generation efficiency (∼0.76 × KH2PO4, ∼0.88 × KH2PO4 at 1064 nm, respectively). According to theoretical calculations, it is speculated that the band gap and NLO characteristics of these two compounds are mostly derived from the B5O10 group and the ScO6 octahedron. Due to the short cutoff edges of I and II, they may be considered as potential NLO materials in the UV and even deep UV spectral ranges. Furthermore, the advent of I and II adds to the diversity of rare earth borates.

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