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1.
Sci Rep ; 14(1): 6281, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491144

RESUMO

The construction of super large section (SLS) shallow buried tunnels involves challenges related to their large span, high flat rate, and complex construction process. Selecting an appropriate excavation method is crucial for ensuring stability, controlling costs, and managing the construction timeline. This study focuses on the selection of excavation methods and the mechanical responses of SLS tunnels in different types of surrounding rock. The research is based on the Yangjiashan tunnel project in Zhejiang Province, China, which is a four-line highway tunnel with a span of 21.3 m. Three sequential excavation methods were proposed and simulated using the three-dimensional finite difference method: the "upper first and lower later" side drift (SD) method, the central diaphragm method, and the top heading and bench (HB) method. The mechanical response characteristics of tunnel construction under these methods were investigated, including rock deformation, rock pressure, and the internal forces acting on the primary support. By comparing the performance of the three construction methods in rock masses of Grades III to V, the study aimed to determine the optimal construction method for SLS tunnels considering factors such as safety, cost, and schedule. Field tests were conducted to evaluate the effectiveness of the optimized construction scheme. The results of the field monitoring indicated that the "upper first and lower later" SD method in Grade V rock mass and the HB method in Grade III to IV rock mass are feasible and cost-effective under certain conditions. The research findings provide valuable insights for the design and construction of SLS tunnels in complex conditions, serving as a reference for engineers and project managers.

2.
Chem Sci ; 14(37): 10203-10211, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37772116

RESUMO

The traditional approach employed in copolymer compositional design, which relies on trial-and-error, faces low-efficiency and high-cost obstacles when attempting to simultaneously improve multiple conflicting properties. For example, designing co-cured polycyanurates that exhibit both moisture and thermal resistance, along with high modulus, is a long-term challenge because of the intrinsic trade-offs between these properties. In this work, to surmount these barriers, we developed a Bayesian optimization (BO)-guided method to expedite the discovery of co-cured polycyanurates exhibiting low water uptake, coupled with higher glass transition temperature and Young's modulus. By virtue of the knowledge of molecular simulations, benchmarking studies were carried out to develop an effective BO-guided method. Propelled by the developed method, several copolymers with improved comprehensive properties were obtained experimentally in a few iterations. This work provides guidance for efficiently designing other high-performance copolymers.

3.
Molecules ; 28(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446859

RESUMO

In this study, ZnAl-layered double hydroxide (ZnAl-LDH) was functionalized with 2-phenylbenzimidazole-5-sulfonic acid (PBSA) to prepare ZnAl-PBSA-LDH using a simple one-step method. The electrochemical impedance spectroscopy (EIS) result of the solution phase demonstrated excellent corrosion inhibition performance of ZnAl-PBSA-LDH. Subsequently, 0.6 wt.% ZnAl-PBSA-LDH with shielding effects and active inhibition was incorporated into the water-based epoxy (WEP) for preparing the high-performance anti-corrosion coating (6-ZPL/WEP). The EIS test illustrated that the 6-ZPL/WEP coating maintained a high low-frequency impedance modulus (|Z0.01 Hz|) after 30 days of immersion, which is nearly two orders of magnitude higher compared to that of the blank coating. These results demonstrated that ZnAl-PBSA-LDH could efficiently improve the corrosion resistance of the WEP coating. Therefore, this study introduces new insights into the use of layered double hydroxides (LDHs) in the domain of anti-corrosion.


Assuntos
Hidróxidos , Água , Hidróxidos/química , Corrosão
4.
ACS Appl Mater Interfaces ; 14(49): 55004-55016, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36456181

RESUMO

Despite advances in machine learning for accurately predicting material properties, forecasting the performance of thermosetting polymers remains a challenge due to the sparsity of historical experimental data and their complicated crosslinked structures. We proposed a machine-learning-assisted materials genome approach (MGA) for rapidly designing novel epoxy thermosets with excellent mechanical properties (high tensile moduli, high tensile strength, and high toughness) through high-throughput screening in a vast chemical space. Machine-learning models were established by combining attention- and gate-augmented graph convolutional networks, multilayer perceptrons, classical gel theory, and transfer learning from small molecules to polymers. Proof-of-concept experiments were carried out, and the structures designed by the MGA were verified. Gene substructures affecting the modulus, strength, and toughness were also extracted, revealing the mechanisms of polymers with high mechanical properties. The developed strategy can be employed to design other thermosetting polymers efficiently.

5.
Entropy (Basel) ; 24(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36554188

RESUMO

We focus on the problem that the Grover algorithm is not suitable for the completely unknown proportion of target solutions. Considering whether the existing quantum classifier used by the current quantum neural network (QNN) to complete the classification task can solve the problem of the classical classifier, this paper proposes a binary quantum neural network classifical model based on an optimized Grover algorithm based on partial diffusion. Trial and error is adopted to extend the partial diffusion quantum search algorithm with the known proportion of target solutions to the unknown state, and to apply the characteristics of the supervised learning of the quantum neural network to binary classify the classified data. Experiments show that the proposed method can effectively retrieve quantum states with similar features. The test accuracy of BQM retrieval under the depolarization noise at the 20th period can reach 97% when the depolarization rate is 0.1. It improves the retrieval accuracy by about 4% and 10% compared with MSE and BCE in the same environment.

6.
Front Med (Lausanne) ; 8: 680871, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095183

RESUMO

Bullous pemphigoid (BP) is the most common type of autoimmune bullous disease and is characterized by the presence of circulating anti-BP180 and/or anti-BP230 autoantibodies. Patients with BP often present with tense blisters and erythema, mainly on the trunk and limbs, but a few patients also have mucosal involvement. In this article, we discuss the fact that BP patients with mucosal involvement tend to have more serious conditions and their disease is more difficult to control. Potential risk factors for mucous involvement include earlier age at onset, drugs such as dipeptidyl peptidase-4 inhibitors, cancer, and blood/serum biomarkers, including lower eosinophil count, higher erythrocyte sedimentation rate, IgG autoantibodies against both the NH2- and COOH-termini of BP180, and the absence of anti-BP230 antibodies. IgA and C3 deposition at the dermo-epidermal junction may also be present. Understanding these risk factors may benefit earlier diagnosis of these patients and promote the development of novel treatments. What's more, it's helpful in deeper understanding of BP development and the relationship between BP and mucous membrane pemphigoid (MMP).

7.
Environ Sci Pollut Res Int ; 28(16): 19822-19837, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33410019

RESUMO

The development and utilization of magnetic nanoadsorption materials with large adsorption capacity and easy separation are the research hotspot nowadays. In this study, nanosheet-assembled maghemite (γ-Fe2O3) magnetic microspheres were successfully synthesized by an environmental friendly, quick, and simple method, for enhanced Sb(III) removal from aqueous solution. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET) were used to characterize the material. The results showed that the product contained flower-like γ-Fe2O3 microspheres composed of petal-shaped nanosheets interspersed with each other. The specific surface area and pore volume were 69.23 m2/g and 0.15 cm3/g, respectively. The material has a strong magnetic response, which allows rapid solid-liquid separation under the action of an external magnetic field. The effects of different dosages, solution pH, and contact time on the adsorption effect were studied by batch adsorption experiments, and the reusability of the materials was evaluated. Both Freundlich isothermal adsorption model and pseudo-second-order kinetic model were able to describe the uptake of Sb(III). The maximum adsorption capacity of the material was 47.48 mg/g under optimal conditions. The adsorption mechanism is mainly that Sb and lattice oxygen (OX2-) form Fe-O-Sb coordination bonds, which is incorporated into the crystal structure of γ-Fe2O3 as inner-sphere surface complexes. The synthetic material has the advantage of simple preparation process, good adsorption capacity, operation over a wide range of pH, and easy physical separation from treatment systems with good potential for future application to treat polluted wastewater.


Assuntos
Poluentes Químicos da Água , Adsorção , Fenômenos Magnéticos , Microesferas , Águas Residuárias
8.
Water Sci Technol ; 82(4): 747-758, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32970626

RESUMO

The eco-friendly and non-toxic natural organic substance, insolubilized humic acid (IHA), was used to remove Mn(II) from aqueous solutions. The adsorption characteristics were studied through a series of static adsorption tests. The results show that conditions such as the dose, the pH of the solution and the initial concentration of Mn(II) all affect removal efficiency, and the optimal pH value was 5.5. The sorption process for Mn(II) on IHA conforms to the pseudo-second-order adsorption kinetic model and intra-particle diffusion is not the only factor affecting the adsorption rate. Both Langmuir and Freundlich models can describe this adsorption behavior, and the experimental maximum adsorption capacity of IHA was 52.87 mg/g under optimal conditions. The thermodynamic analysis of adsorption shows that the adsorption process is a non-spontaneous endothermic physical reaction. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were used to characterize the samples, it was found that as IHA successfully adsorbed Mn(II), the surface morphology of IHA changed after the adsorption reaction. The adsorption mechanism for Mn(II) on IHA is to provide electron pairs for carboxyl, phenolic hydroxyl and other functional groups to form stable complexes with Mn(II).


Assuntos
Poluentes Químicos da Água/análise , Adsorção , Substâncias Húmicas , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(2): 365-370, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-28446276

RESUMO

OBJECTIVE: To explore the clinical features and prognostic factors of pediatric acute lymphoblastic leukemia (ALL) in high-risk (HR) group. METHODS: A total of 421 children with ALL in the Children's Hospital of Soochow University from August 2008 to March 2013 were diagnosed and treated according to the Chinese Children Leukemia Group (CCLG)-2008 Protocol. Among different risk-groups, 148 cases were stratified into the low-risk group and 191 cases were included in the moderate-risk group. Eight-two patients of the high-risk group were analyzed retrospectively for their clinical features, 5-year event-free survival (EFS) rate and overall survival (OS) rate. RESULTS: The median follow-up times of 82 patients were 64 months(3.0-76.3 months), 55 patient achieved complete remission(CR) after 1 cycle of induction chemotherapy(CR rate 67.1%), 25 patients relapsed(30.5%) mainly in very early and early relapse phases, significantly different from the low-risk group (P=0.013), 27 pateitns died(32.9%). The 5-year pEFS and pOS were 57.20% and 58.5%, respectively. Ph+ or BCR/ABL+ and MRD>10-2 on the 33rd day in the high-risk group were 2 main factors influencing EFS and OS according to single factor analysis. Ph+ or BCR/ABL+ was an independent prognostic factor, however, the MRD value on the 33rd day was not statistically significant differente by virtue of COX regression analysis. CONCLUSION: The clinical feature of children with ALL in high risk group display low induction CR rate, high recurrence rate and the lower 5-year pEFS. Ph+ or BCR/ABL+ is regarded as an independent factor of poor prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Criança , Intervalo Livre de Doença , Humanos , Quimioterapia de Indução , Prognóstico , Indução de Remissão , Resultado do Tratamento
10.
Food Chem ; 228: 204-210, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28317714

RESUMO

The effects of acetic acid pretreatment on the texture of cooked potato slices were investigated in this work. Potato slices were pretreated with acetic acid immersion (AAI), distilled water immersion (DWI), or no immersion (NI). Subsequently, the cell wall material of the pretreated samples was isolated and fractioned to evaluate changes in the monosaccharide content and molar mass (MM), and the hardness and microscopic structure of the potato slices in different pretreatments before and after cooking were determined. The results showed that the highest firmness was obtained with more intact structure of the cell wall for cooked potato slices with AAI pretreatment. Furthermore, the MM and sugar ratio demonstrated that the AAI pretreated potato slices contained a higher content of the small molecular polysaccharides of cell walls, especially in the hemicellulose fraction. This work may provide a reference for potato processing.


Assuntos
Ácido Acético/química , Parede Celular/efeitos dos fármacos , Polissacarídeos/química , Solanum tuberosum/química , Culinária/métodos , Dureza
11.
Food Chem ; 211: 409-14, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27283649

RESUMO

Pretreatments such as low temperature blanching and/or calcium soaking affect the cooked texture of vegetal food. In the work, lotus rhizomes (Nelumbo nucifera Gaertn.) were pretreated using the following 4 treatments, blanching at 40°C, blanching at 90°C, soaking in 0.5% CaCl2, and blanching at 40°C followed by immersion in 0.5% CaCl2. Subsequently, the cell wall material of pretreated samples was isolated and fractioned to identify changes in the degree of esterification (DE) and monosaccharide content of each section, and the texture of the lotus rhizomes in different pre-treatments was determined after thermal processing with different time. The results showed that the greatest hardness was obtained after blanching at 40°C in CaCl2, possibly attributing to the formation of a pectate calcium network, which maintains the integrity of cell walls. Furthermore, the content of galactose, rhamnose and arabinose decreased due to the breakage of sugar backbones and subsequent damage to cell walls. Our results may provide a reference for lotus rhizome processing.


Assuntos
Cálcio/toxicidade , Temperatura Alta/efeitos adversos , Nelumbo/química , Nelumbo/efeitos dos fármacos , Rizoma/química , Rizoma/efeitos dos fármacos , Antioxidantes/análise , Antioxidantes/química , Cálcio/administração & dosagem , Fenômenos Químicos/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/química
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