In this note, we establish a boundary maximum principle for a class of stationary pairs of varifolds satisfying a fixed contact angle condition in any compact Riemannian manifold with smooth boundary.
In this note, we establish a boundary maximum principle for a class of stationary pairs of varifolds satisfying a fixed contact angle condition in any compact Riemannian manifold with smooth boundary.
Direct arylation polycondensation(DArP)has emerged as an eco-friendly and atom-efficient methodology for the syntheses ofπ-conjugated polymers(CPs).This approach features the direct C—H arylation of an aromatic hydr...
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Direct arylation polycondensation(DArP)has emerged as an eco-friendly and atom-efficient methodology for the syntheses ofπ-conjugated polymers(CPs).This approach features the direct C—H arylation of an aromatic hydrocarbon with an aryl *** the prevalence of thiophene-containing CPs,achieving efficient and defect-free DArP of thiophene-based C−H monomers is of great *** review presents a mechanistic insight into DArP and describes the development of DArP catalytic systems for varied thiophene-based C−H ***,the control of the primary defects(i.e.,branching and homo-coupling)in thiophene-based DArP is also *** emphasizing the principles behind monomer selection and catalytic system optimization,this review intends to provide a framework for future advancements in the DArP of thiophene-containing CPs.
Acupuncture has thousands of years of history and perspective for the treatment of many health problems and disorders. Beneficial effects of acupuncture on obesity have been demonstrated at various levels in animals a...
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Acupuncture has thousands of years of history and perspective for the treatment of many health problems and disorders. Beneficial effects of acupuncture on obesity have been demonstrated at various levels in animals and clinical trials, with almost no adverse effect, even when combined with local electrical stimulation, i.e., electroacupuncture (EA), a way to potentiate the effects of acupuncture. However, there is still scattered evidence about the impact of EA on brain functions related to the control of eating behavior, and notably on the gut-brain axis mechanisms involved in these putative central modulations. During the past 10 years, we have described a convincing diet-induced obese minipig model, and successfully implemented brain imaging and neurocognitive approaches to challenge mechanistic hypotheses and innovative therapeutic strategies. In the present article, we propose to confront the current literature on the acupuncture and EA effects on the gut-brain axis and obesity with the latest developments in nutrition and neuroscience research using the minipig model. Our aims are to (a) elaborate functional hypotheses on the gut-brain mechanisms underlying EA effects on obesity, and especially on the role of the vagus nerve, and (b) present the rational for testing these hypotheses in the minipig model.
Although the Transformer model has outperformed traditional sequence-To-sequence model in a variety of natural language processing (NLP) tasks, it still suffers from semantic irrelevance and repetition for abstractive...
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In this paper, we show that any embedded capillary hypersurface in the half-space with anisotropic constant mean curvature is a truncated Wulff shape. This extends Wente's result (Pac J Math 88:387-397, 1980. ) to...
In this paper, we show that any embedded capillary hypersurface in the half-space with anisotropic constant mean curvature is a truncated Wulff shape. This extends Wente's result (Pac J Math 88:387-397, 1980. ) to the anisotropic case and He-Li-Ma-Ge's result (Indiana Univ Math J 58(2):853-868, 2009. ) to the capillary boundary case. The main ingredients in the proof are a new Heintze-Karcher inequality and a new Minkowski formula, which have their own interest.
In this paper, we first prove a rigidity result for a Serrin-type partially overdetermined problem in the half-space, which gives a characterization of capillary spherical caps by the overdetermined problem. In the se...
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In this paper, we first prove a rigidity result for a Serrin-type partially overdetermined problem in the half-space, which gives a characterization of capillary spherical caps by the overdetermined problem. In the second part, we prove quantitative stability results for the Serrin-type partially overdetermined problem, as well as capillary almost constant mean curvature hypersurfaces in the half-space.
Methane,as the main component of natural gas,is a key transitional fuel resource due to its abundance and relatively low carbon emissions,aligning with global carbon neutrality objectives[1].Traditional natural gas st...
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Methane,as the main component of natural gas,is a key transitional fuel resource due to its abundance and relatively low carbon emissions,aligning with global carbon neutrality objectives[1].Traditional natural gas storage methods,such as liquefied and compressed natural gas,require costly infrastructure and high-pressure ***,adsorbed natural gas offers a safer,more cost-effective,and environmentally friendly solution by enhancing storage capacity at reduced pressures through the use of methane adsorbents[2].
Direct coal liquefaction in the heating stage of Shenhua Shendong bituminous coal was carried out in a 0.01 t/d continuous tubular facility with iron catalyst and hydrogenated anthracene and wash oil as solvent at a r...
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Direct coal liquefaction in the heating stage of Shenhua Shendong bituminous coal was carried out in a 0.01 t/d continuous tubular facility with iron catalyst and hydrogenated anthracene and wash oil as solvent at a residence time (t) of 3.56.5 min and a reaction temperature (T) of 340-450 degrees C. The results show that when t = 3.5 min and T = 340 degrees C, a cracking reaction of coal occurs, while the oil yield was almost zero. As the residence time and temperature each increase, coal conversion and product yield exhibit different change patterns. Especially when t = 6.5 min and T = 450 degrees C: under these conditions, the coal conversion and oil yield reached 83.67 and 52.27 wt?%, respectively. To investigate the liquefaction kinetics, a 8-lump reaction kinetic model which follow first-order irreversible reactions (r = k(i) dC/dt) was developed to estimate the rate constants. The results indicated that the model is perfectly valid for the heating stage, and the yield of oil and gas were mainly from coal other than preasphaltene (PAA).
Indonesian brown coal is analyzed using C-13 cross-polarization/magic angle spinning nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction (...
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Indonesian brown coal is analyzed using C-13 cross-polarization/magic angle spinning nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction (XRD) to obtain the information and parameters of the coal structural unit. A macromolecular structural model of Indonesian brown coal was constructed on the basis of the structural parameters and elemental analysis results. The C-13 chemical shift of this model was calculated using the ACD/C-13 NMR predictor. The results indicate that the aromaticity of Indonesian brown coal is 0.3412, and the structures of aromatic carbon are mainly types of naphthalene and benzene. The ratio of bridge carbon/surrounding carbon is 0.0696. Oxygen in the structural model mainly exists in the form of phenolic hydroxyl oxygen, carboxyl oxygen, and ether oxygen, of which phenolic hydroxyl oxygen and carboxyl oxygen are the most prominent. Nitrogen atom exists in the form of pyridine and pyrrole. The peak of XRD spectra at 20-30 degrees is broad with a strong gamma width. The calculated chemical shift spectrogram of the model is highly consistent with that of the experimental results. The structural formula calculated for Indonesian brown coal is C190H170O50N2. This information will be the basis of making use of Indonesian brown coal.
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