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1.
Med Sci Monit ; 30: e942888, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38576138

RESUMEN

BACKGROUND This retrospective study aimed to compare patient outcomes from standard total knee arthroplasty (TKA) vs navigation-guided arthroplasty using the Brainlab software-guided surgical system at Cangzhou Hospital of Integrated TCM-WM, Hebei, Hebei Province, China from January 2021 to July 2023. MATERIAL AND METHODS A total of 239 patients who underwent total knee arthroplasty in Cangzhou Hospital of Integrated TCM-WM, Hebei from January 2021 to July 2023 were retrospectively analyzed. According to the inclusion criteria, 212 eligible patients were selected for analysis and divided into a Navigation Group (NG) (n=105) and a Traditional Group (TG) (n=107) according to surgical method used. Outcomes measured included duration of disease, operative time, intraoperative blood loss volume, postoperative length of hospital stay, and pain measured by the hospital for special surgery knee score (HSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and forgotten joint score (FJS). RESULTS The comparison of perioperative results between the 2 groups showed that the incision length in the NG was significantly longer than that in the TG (P<0.001, 95% Cl 2.59-3.35). At 3 months after surgery, the HSS score of the NG was statistically higher than that of the TG (P=0.002, 95% Cl 3.42-4.46); the WOMAC score of the NG was lower than that of the TG (P<0.001, 95% Cl -4.41-2.87); and the FJS score of the NG was significantly higher than that of the TG (P=0.003, 95% Cl 2.39-3.67). CONCLUSIONS Compared with conventional TKA, use of the Brainlab navigation system is associated with a longer incision, more accurate implantation position of the prosthesis, faster recovery of knee joint function, and helps patients to "forget" about their knee prosthesis in the short term.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Herida Quirúrgica , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Estudios Retrospectivos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Resultado del Tratamiento
2.
Adv Mater ; : e2400285, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38613131

RESUMEN

Bismuth-telluride-based alloy has long been considered as the most promising candidate for low-grade waste heat power generation. However, optimizing the thermoelectric performance of n-type Bi2Te3 is more challenging than that of p-type counterparts due to its greater sensitivity to texture, and thus limits the advancement of thermoelectric modules. Herein, the thermoelectric performance of n-type Bi2Te3 is enhanced by incorporating a small amount of CuGaTe2, resulting in a peak ZT of 1.25 and a distinguished average ZT of 1.02 (300-500 K). The decomposed Cu+ strengthens interlayer interaction, while Ga+ optimizes carrier concentration within an appropriate range. Simultaneously, the emerged numerous defects, such as small-angle grain boundaries, twin boundaries, and dislocations, significantly suppresses the lattice thermal conductivity. Based on the size optimization by finite element modelling, the constructed thermoelectric module yields a high conversion efficiency of 6.9% and output power density of 0.31 W cm-2 under a temperature gradient of 200 K. Even more crucially, the efficiency and output power little loss after subjecting the module to 40 thermal cycles lasting for 6 days. This study demonstrates the efficient and reliable Bi2Te3-based thermoelectric modules for broad applications in low-grade heat harvest.

3.
Small ; : e2312288, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38431966

RESUMEN

The development of capable of simultaneously modulating the sluggish electrochemical kinetics, shuttle effect, and lithium dendrite growth is a promising strategy for the commercialization of lithium-sulfur batteries. Consequently, an elaborate preparation method is employed to create a host material consisting of multi-channel carbon microspheres (MCM) containing highly dispersed heterostructure Fe3 O4 -FeTe nanoparticles. The Fe3 O4 -FeTe@MCM exhibits a spontaneous built-in electric field (BIEF) and possesses both lithophilic and sulfophilic sites, rendering it an appropriate host material for both positive and negative electrodes. Experimental and theoretical results reveal that the existence of spontaneous BIEF leads to interfacial charge redistribution, resulting in moderate polysulfide adsorption which facilitates the transfer of polysulfides and diffusion of electrons at heterogeneous interfaces. Furthermore, the reduced conversion energy barriers enhanced the catalytic activity of Fe3 O4 -FeTe@MCM for expediting the bidirectional sulfur conversion. Moreover, regulated Li deposition behavior is realized because of its high conductivity and remarkable lithiophilicity. Consequently, the battery exhibited long-term stability for 500 cycles with 0.06% capacity decay per cycle at 5 C, and a large areal capacity of 7.3 mAh cm-2 (sulfur loading: 9.73 mg cm-2 ) at 0.1 C. This study provides a novel strategy for the rational fabrication of heterostructure hosts for practical Li-S batteries.

4.
Small ; 20(12): e2306701, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37948419

RESUMEN

Bi2Te3-based alloys are the benchmark for commercial thermoelectric (TE) materials, the widespread demand for low-grade waste heat recovery and solid-state refrigeration makes it imperative to enhance the figure-of-merits. In this study, high-performance Bi0.5Sb1.5Te3 (BST) is realized by incorporating Cu2GeSe3 and Se. Concretely, the diffusion of Cu and Ge atoms optimizes the hole concentration and raises the density-of-states effective mass (md *), compensating for the loss of "donor-like effect" exacerbated by ball milling. The subsequent Se addition further increases md *, enabling a total 28% improvement of room-temperature power factor (S2σ), reaching 43.6 µW cm-1 K-2 compared to the matrix. Simultaneously, the lattice thermal conductivity is also significantly suppressed by multiscale scattering sources represented by Cu-rich nanoparticles and dislocation arrays. The synergistic effects yield a peak ZT of 1.41 at 350 K and an average ZT of 1.23 (300-500 K) in the Bi0.5Sb1.5Te2.94Se0.06 + 0.11 wt.% Cu2GeSe3 sample. More importantly, the integrated 17-pair TE module achieves a conversion efficiency of 6.4%, 80% higher than the commercial one at ΔT = 200 K. These results validate that the facile composition optimization of the BST/Cu2GeSe3/Se is a promising strategy to improve the application of BST-based TE modules.

5.
Small ; 20(16): e2306914, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38041488

RESUMEN

Electrocatalysts with high activity and durability for acidic oxygen evolution reaction (OER) play a crucial role in achieving cost-effective hydrogen production via proton exchange membrane water electrolysis. A novel electrocatalyst, Te-doped RuO2 (Te-RuO2) nanotubes, synthesized using a template-directed process, which significantly enhances the OER performance in acidic media is reported. The Te-RuO2 nanotubes exhibit remarkable OER activity in acidic media, requiring an overpotential of only 171 mV to achieve an anodic current density of 10 mA cm-2. Furthermore, they maintain stable chronopotentiometric performance under 10 mA cm-2 in acidic media for up to 50 h. Based on the experimental results and density functional calculations, this significant improvement in OER performance to the synergistic effect of large specific surface area and modulated electronic structure resulting from the doping of Te cations is attributed.

6.
Small Methods ; 8(3): e2301256, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38009750

RESUMEN

Power generation modules utilizing thermoelectric (TE) materials are suitable for recycling widespread low-grade waste heat (<600 K), highlighting the immediate necessity for advanced Bi2 Te3 -based alloys. Herein, the substantial enhancement in TE performance of the p-type Bi0.4 Sb1.6 Te3 (BST) sintered sample is realized by subtly incorporating the non-stoichiometric Ag5 Te3 and counteractive Se. Specifically, Ag atoms diffused into the BST lattice improve the density-of-states effective mass (md * ) and boost the hole concentration for the suppressed bipolar effect. The addition of Se further improves md * prompting the room-temperature power factor upgrade to 46 W cm-1  K-2 . Concurrently, the lattice thermal conductivity is considerably lowered by multiple scattering sources exemplified by Sb-rich nanoprecipitates and dense dislocations. These synergistic results yield a high peak ZT of 1.44 at 375 K and an average ZT of 1.28 between 300 and 500 K in the Bi0.4 Sb1.6 Te2.95 Se0.05 + 0.05 wt.% Ag5 Te3 sample. More significantly, when coupled with n-type zone-melted Bi2 Te2.7 Se0.3 , the integrated 17-pair TE module achieves a competitive conversion efficiency of 6.1% and an output power density of 0.40 W cm-2 at a temperature difference of 200 K, demonstrating great potential for practical applications.

7.
Angew Chem Int Ed Engl ; 62(33): e202305571, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37312245

RESUMEN

Maximizing hole-transfer kinetics-usually a rate-determining step in semiconductor-based artificial photosynthesis-is pivotal for simultaneously enabling high-efficiency solar hydrogen production and hole utilization. However, this remains elusive yet as efforts are largely focused on optimizing the electron-involved half-reactions only by empirically employing sacrificial electron donors (SEDs) to consume the wasted holes. Using high-quality ZnSe quantum wires as models, we show that how hole-transfer processes in different SEDs affect their photocatalytic performances. We found that larger driving forces of SEDs monotonically enhance hole-transfer rates and photocatalytic performances by almost three orders of magnitude, a result conforming well with the Auger-assisted hole-transfer model in quantum-confined systems. Intriguingly, further loading Pt cocatalyts can yield either an Auger-assisted model or a Marcus inverted region for electron transfer, depending on the competing hole-transfer kinetics in SEDs.

8.
J AOAC Int ; 106(5): 1313-1322, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37252833

RESUMEN

BACKGROUND: Cimicifugae Rhizoma, known in Chinese as Shengma, is a common medicinal material in traditional Chinese medicine (TCM), mainly used for treating wind-heat headaches, sore throat, uterine prolapse, and other diseases. OBJECTIVES: An approach using a combination of ultra-performance liquid chromatography (UPLC), MS, and multivariate chemometric methods was designed to assess the quality of Cimicifugae Rhizoma. METHODS: All materials were crushed into powder and the powdered sample was dissolved in 70% aqueous methanol for sonication. Chemometric methods, including hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least-squares discriminant analysis (OPLS-DA), were adopted to classify and perform a comprehensive visualization study of Cimicifugae Rhizoma. The unsupervised recognition models of HCA and PCA obtained a preliminary classification and provided a basis for classification. In addition, we constructed a supervised OPLS-DA model and established a prediction set to further validate the explanatory power of the model for the variables and unknown samples. RESULTS: Exploratory research found that the samples were divided into two groups, and the differences were related to appearance traits. The correct classification of the prediction set also demonstrated a strong predictive ability of the models for new samples. Subsequently, six chemical makers were characterized by UPLC-Q-Orbitrap-MS/MS, and the content of four components was determined. The results of the content determination revealed the distribution of representative chemical markers caffeic acid, ferulic acid, isoferulic acid, and cimifugin in two classes of samples. CONCLUSIONS: This strategy can provide a reference for assessing the quality of Cimicifugae Rhizoma, which is significant for the clinical practice and QC of Cimicifugae Rhizoma. HIGHLIGHTS: The HCA, PCA and OPLS-DA models visually classify Cimicifugae Rhizoma by appearance traits and obtain the chemical markers that influence the classification. The training and prediction sets were built to demonstrate the accuracy of the classification. Advanced UPLC-Q-Orbitrap-MS/MS technology provides powerful elucidation of critical chemical markers.


Asunto(s)
Medicamentos Herbarios Chinos , Espectrometría de Masas en Tándem , Femenino , Humanos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Quimiometría , Cromatografía Liquida , Medicamentos Herbarios Chinos/química
9.
Adv Mater ; 35(21): e2300338, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36862991

RESUMEN

As the sole dominator of the commercial thermoelectric (TE) market, Bi2 Te3 -based alloys play an irreplaceable role in Peltier cooling and low-grade waste heat recovery. Herein, to improve the relative low TE efficiency determined by the figure of merit ZT, an effective approach is reported for improving the TE performance of p-type (Bi,Sb)2 Te3 by incorporating Ag8 GeTe6 and Se. Specifically, the diffused Ag and Ge atoms into the matrix conduce to optimized carrier concentration and enlarge the density-of-states effective mass while the Sb-rich nanoprecipitates generate coherent interfaces with little loss of carrier mobility. The subsequent Se dopants introduce multiple phonon scattering sources and significantly suppress the lattice thermal conductivity while maintaining a decent power factor. Consequently, a high peak ZT of 1.53 at 350 K and a remarkable average ZT of 1.31 (300-500 K) are attained in the Bi0.4 Sb1.6 Te0.95 Se0.05  + 0.10 wt% Ag8 GeTe6 sample. Most noteworthily, the size and mass of the optimal sample are enlarged to Ø40 mm-200 g and the constructed 17-couple TE module exhibits an extraordinary conversion efficiency of 6.3% at ΔT = 245 K. This work demonstrates a facile method to develop high-performance and industrial-grade (Bi,Sb)2 Te3 -based alloys, which paves a strong way for further practical applications.

10.
Neuroradiology ; 65(1): 215-223, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36394613

RESUMEN

PURPOSE: To describe vertebral artery (VA) variation in patients with or without osseous anomalies at congenital craniovertebral junction (CVJ). METHODS: In the present study, we retrospectively analyzed 258 patients with VA variation who underwent three-dimensional computed tomography angiography (3D CTA) in our hospital from March 2017 to October 2019. RESULTS: Among 258 patients, 180 were accompanied by skeleton structural malformation, including 105 cases of occipital ossification of the atlas, 8 cases of the bipartite atlas, 7 cases of hypoplasia of the posterior arch of the atlas, 45 cases of C2/3 congenital fusion, 2 cases of C2/3/4 congenital fusion, and 13 cases of congenital os odontoid. VA variation was divided into type A (VA variation in the CVJ area without osseous anomalies) and type B (VA variation in the CVJ area with osseous anomalies). There are totally 10 subtypes, including type A1 (atlas occipitalization with VA entrance approach close to middle line, 20.2%); type A2 (atlas occipitalization with VA entrance approach far from middle line, 30.2%); type A3 (first intersegmental VA in C1-C2, 1.9%); type A4 (fenestration of the VA, 2.3%); type A5 (VA bulging type, 6.6%); type A6 (VA exposures with the absence of the posterior atlas arch, 2.3%); type A7 (C2 inner wall type, 0.4%); type A8 (single vertebral artery, 2.3%); type B1 (posterior ponticuli, 2.7%); and type B2 (high-riding VA, 31.4%). CONCLUSION: This study is expected to take the lead in the most comprehensive classification of VA variation.


Asunto(s)
Angiografía por Tomografía Computarizada , Arteria Vertebral , Humanos , Arteria Vertebral/diagnóstico por imagen , Arteria Vertebral/anomalías , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Angiografía
11.
Natl Sci Rev ; 9(10): nwac025, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36415320

RESUMEN

Beyond the state-of-the-art Cd-containing quantum wires (QWs), heavy-metal-free semiconductor QWs, such as ZnSe, are of great interest for next-generation environmental-benign applications. Unfortunately, simultaneous, on-demand manipulation of their radial and axial sizes-that allows strong quantum confinement in the blue-light region-has so far been challenging. Here we present a two-step catalyzed growth strategy that enables independent, high-precision and wide-range controls over the diameter and length of ZnSe QWs. We find that a new epitaxial orientation between the cubic-phase Ag2Se solid catalyst and wurtzite ZnSe QWs kinetically favors the formation of defect-free ultrathin QWs. Thanks to their high uniformity, the resulting blue-light-active, phase-pure ZnSe QWs exhibit well-defined excitonic absorption with the 1Se-1Sh transition linewidth as narrow as sub-13 nm. Combining the transient absorption spectroscopy, we further show that surface electron traps in these ZnSe QWs can be eliminated by thiol passivation, which results in long-lived charge carriers and high-efficiency solar-to-hydrogen conversion.

12.
J Am Chem Soc ; 144(45): 20620-20629, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36332107

RESUMEN

Facilitating charge separation and transport of semiconductors is pivotal to improving their solar-to-hydrogen conversion efficiency. To this end, manipulating the charge dynamics via element doping has attracted much attentions. Here, we doped phosphorus (P) into two-dimensional (2D) single-crystalline quaternary sulfide (SCQS) nanobelts, enabling significantly enhanced photocatalytic H2 production. By carefully studying the carrier dynamics after P doping, we found that the introduction of P leads to a narrowed band gap, inhibits the recombination of photogenerated carriers, and increases the electric conductivity, all of which contributed to their improved catalytic performance. Meanwhile, the inherited single-crystalline structure and exposed (0001) facet favors carrier transport and photocatalytic hydrogen production. It has been found that the P-doped Cu-Zn-In-S (CZIS) nanobelts exhibit a visible-light photocatalytic hydrogen production rate of 12.2 mmol h-1 g-1 without cocatalysts, which is 3.5-fold higher than that of pristine CZIS nanobelts. Moreover, the P doping strategy is proven to be common to other semiconductors, such as single-crystalline Cu-Zn-Ga-S (CZGS) nanobelts. Our work provides an efficient way to manipulate charge carriers and will help develop high-efficiency photocatalysts.

13.
Food Sci Nutr ; 10(7): 2470-2475, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35844925

RESUMEN

The muscle from Xilingol indigenous sheep breeds are famous in China, and the FecB genotype in this population remains uncharacterized. In this study, SNPs in the FecB locus were investigated by pyrosequencing, and an optimized PCR-RFLP technique was generated to identify SNPs. In addition, an efficient technique for high-throughput identification of SNPs in FecB was optimized using TaqMan real-time PCR and breed-conservative primers and SNP-specific probes. By genotyping the FecB locus in the muscle of Xilingol indigenous sheep breeds using a novel TaqMan real-time PCR assay, our study has generated the groundwork for the authentication of Xilingol mutton based on the specific gene and the prolificacy-oriented breeding of Xilingol sheep using marker-assisted selection strategies in the future.

14.
ACS Appl Mater Interfaces ; 14(25): 29032-29038, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35704789

RESUMEN

In the mid-temperature region, SnTe is a promising substitute for PbTe, whereas the thermoelectric (TE) property of pristine SnTe is severely limited by the good thermal conductivity and inferior Seebeck coefficient. In this research, we synergistically manipulate the interdependent TE parameters of SnTe-AgBiTe2 alloys by Mn doping to increase the ZT value. The AgBiTe2 alloying is found to greatly reduce the electrical conductivity and electronic contribution for thermal transport by reducing the carrier mobility, while Mn doping obviously improves the Seebeck coefficient by effectively decreasing the valence band offset. The lowest κl of Mn-doped SnTe-AgBiTe2 alloys is 0.49 W m-1 K-1 at 823 K since the various defects strengthen the phonon scattering. Collectively, these manipulations yield a peak ZT value of 1.40 at 823 K and an average ZT value of 0.73 (300-823 K) in the Mn-doped SnTe-AgBiTe2 alloys. This research suggests that Mn doping is a valid scheme to constantly improve the thermoelectric property of SnTe-AgBiTe2 alloys in a wide temperature range.

15.
Dalton Trans ; 51(15): 6103-6111, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35357382

RESUMEN

Although lithium-sulfur (Li-S) batteries possess great potential to become the next generation of energy storage technology due to their fivefold higher energy density than commercial lithium-ion batteries, their practical application is still hindered by their poor cycling stability, especially resulting from the disturbing shuttle effect of soluble intermediates. In this study, vanadium dioxide (VO2) nanosheets were successfully grown onto CNTs to form CNTs@VO2 through hydrothermal and calcining processes. The hollow structure of the high conductive CNTs offers internal space and mesopores to accommodate the electrolyte combined with the polar metal oxide VO2 nanosheets providing the chemical anchoring. The hollow binary core-shell host acting as the nanoreactor that serves as the modifier of the separator results in the intensive physical and chemical dual adsorption of lithium polysulfide species (LiPSs), promoting the conversion of long-chain LiPSs to alleviate the shuttle effect significantly and boosting the performance. In addition, the CNTs enhance the electronic conductivity and the electrolyte infiltration of the separator. Notably, the modified separator demonstrates a high initial discharge capacity of 1397 mA h g-1 at 0.2C and retains a stable cycling ability with a reversible capacity of 965 mA h g-1 over 200 cycles at 1C. Even for the high sulfur loading of 7.4 mg cm-2, it can deliver a high areal capacity of 5.4 mA h cm-2 at 0.5C.

16.
Aging (Albany NY) ; 14(1): 497-508, 2022 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-35027503

RESUMEN

AIM: To explore the function of circular RNA CUL2 (circCUL2) in colorectal cancer progression. METHOD: RT-PCR was carried out to detect the expression of circCUL2 in colorectal cancer tissues and cell lines. Western blot and immunofluorescence were used to determine the level of autophagy. CCK-8, clone formation assay, and EdU staining were used to assess the proliferation ability. Luciferase assay verified the relationship between miR-208a-3p and circCUL2 /PPP6C. The xenograft mouse model was used to confirm the function of circCUL2 in vivo. RESULTS: The expression level of circCUL2 was down-regulated in colorectal cancer tissues and cell lines. Forcing expression of circCUL2 inhibited proliferation ability, induced apoptosis, and autophagy in colorectal cancer cells. Luciferase assay verified that miR-208a-3p could bind with circCUL2/PPP6C. Overexpression of circCUL2 could inhibit cancer progression via targeting the miR-208a-3p/PPP6C signal pathway. CONCLUSION: CircCUL2 participates in progression via the miR-208a-3p/PPP6C axis in colorectal cancer. CircCUL2 would be an underlying target for the diagnosis and therapy of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Proteínas Cullin/metabolismo , Proteínas del Citoesqueleto/metabolismo , MicroARNs/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , ARN Circular/metabolismo , Factores de Transcripción/metabolismo , Apoptosis/fisiología , Autofagia/fisiología , Línea Celular Tumoral , Proteínas Cullin/genética , Proteínas del Citoesqueleto/genética , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Fosfoproteínas Fosfatasas/genética , Factores de Transcripción/genética
17.
ACS Appl Mater Interfaces ; 13(48): 57514-57520, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34817164

RESUMEN

Zone-melted Bi2Te3-based alloys are the only commercially available thermoelectric (TE) materials, but they suffer from mediocre figure of merit (ZT) values and brittleness. In this work, we prepared Bi0.48Sb1.52Te3 sintered samples using a hot-pressing method and added tiny AgCuTe to improve the comprehensive properties. Because the carrier concentration is boosted by the AgCuTe addition, the bipolar effect at higher temperature is explicitly suppressed and the power factor is also improved in a broad temperature scope. Simultaneously, κlat is mostly diminished by the introduced phonon scattering centers comprising point defects, dislocations, and grain boundaries. Consequently, we achieved a ZTmax of 1.25 at 350 K and its average ZTave of 1.1 from 300 to 500 K in the (Bi0.48Sb1.52Te3 + 3 wt % Te) + 0.12 wt % AgCuTe sample. Composed of this sample and commercial Bi2Te2.5Se0.5, the fabricated TE module manifests a maximum power output density of 0.31 W cm-2 (Tcold = 300 K and Thot = 500 K). This work suggests that AgCuTe-doped Bi0.48Sb1.52Te3 is promising for recovering low-grade thermal energy near room temperature.

18.
Phys Chem Chem Phys ; 23(33): 17866-17872, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34378579

RESUMEN

The emerging material GeMnTe2 provides a rare example to study the spin degree of freedom in thermoelectric transport, as it exhibits an anomalous Seebeck coefficient driven by the spin's thermodynamic entropy. This work presents an unconventional strategy to optimize the thermoelectric performance of GeMnTe2 by manipulating the spin degree of freedom. NaBiTe2 is alloyed into GeMnTe2 to disorder the spin orientation under finite temperature, and the obtained Seebeck coefficient is confirmed to be dramatically enhanced by more than 150%. The measurements of XRD and magnetic susceptibility indicate that the increased Seebeck coefficient is due to the increase of the spin's thermodynamic entropy. Finally, the maximum ZT of 1.06 at 820 K is obtained in Ge0.8Na0.1Bi0.1MnTe2. This work enriches the physical picture of spin degree of freedom in thermoelectric materials.

19.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3270-3287, 2021 Jul.
Artículo en Chino | MEDLINE | ID: mdl-34396746

RESUMEN

The multi-component pharmacokinetic study of Chinese herbal extracts elaborates the in vivo processes,including absorption,distribution,metabolism,and excretion,of multiple bioactive components,which is of significance in revealing pharmacodynamic material basis of Chinese herbal medicine. In recent years,with the innovation in ideas,and development of techniques and methods on traditional Chinese medicine( TCM) research,the pharmacokinetic studies of Chinese herbal extracts were extensively performed,and notable progress has been made. This paper reviewed the advancement of multi-component pharmacokinetics of Chinese herbal extracts in recent five years from analysis technology of biological sample,the pharmacokinetic characteristics of Chinese herbal medicine with complex system,and the impacts of processing and pathological state on pharmacokinetics of Chinese herbal extracts,aiming to provide a reference for quality control,product development and rational medication of Chinese herbal extracts.


Asunto(s)
Medicamentos Herbarios Chinos , China , Humanos , Medicina Tradicional China , Control de Calidad
20.
Nat Commun ; 12(1): 4296, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34262051

RESUMEN

Photoelectrochemical catalysis is an attractive way to provide direct hydrogen production from solar energy. However, solar conversion efficiencies are hindered by the fact that light harvesting has so far been of limited efficiency in the near-infrared region as compared to that in the visible and ultraviolet regions. Here we introduce near-infrared-active photoanodes that feature lattice-matched morphological hetero-nanostructures, a strategy that improves energy conversion efficiency by increasing light-harvesting spectral range and charge separation efficiency simultaneously. Specifically, we demonstrate a near-infrared-active morphological heterojunction comprised of BiSeTe ternary alloy nanotubes and ultrathin nanosheets. The heterojunction's hierarchical nanostructure separates charges at the lattice-matched interface of the two morphological components, preventing further carrier recombination. As a result, the photoanodes achieve an incident photon-to-current conversion efficiency of 36% at 800 nm in an electrolyte solution containing hole scavengers without a co-catalyst.

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