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41.
To scientifically and effectively evaluate the service capacity of expressway service areas (ESAs) and improve the management level of ESAs, we propose a method for the recognition of vehicles entering ESAs (VeESAs) and estimation of vehicle dwell times using electronic toll collection (ETC) data. First, the ETC data and their advantages are described in detail, and then the cleaning rules are designed according to the characteristics of the ETC data. Second, we established feature engineering according to the characteristics of VeESA and proposed the XGBoost-based VeESA recognition (VR-XGBoost) model. Studied the driving rules in depth, we constructed a kinematics-based vehicle dwell time estimation (K-VDTE) model. The field validation in Part A/B of Yangli ESA using real ETC transaction data demonstrates that the effectiveness of our proposal outperforms the current state-of-the-art. Specifically, in Part A and Part B, the recognition accuracies of VR-XGBoost are 95.9% and 97.4%, respectively, the mean absolute errors (MAEs) of dwell time are 52 and 14 s, respectively, and the root mean square errors (RMSEs) are 69 and 22 s, respectively. In addition, the confidence level of controlling the MAE of dwell time within 2 min is more than 97%. This work can effectively recognize the VeESA and accurately estimate the dwell time, which can provide a reference idea and theoretical basis for the service capacity evaluation and layout optimization of the ESA.  相似文献   
42.
Porous aromatic framework materials with high stability, sensitivity, and selectivity have great potential to provide new sensors for optoelectronic/fluorescent probe devices. In this work, a luminescent porous aromatic framework material (LNU-23) was synthesized via the palladium-catalyzed Suzuki cross-coupling reaction of tetrabromopyrene and 1,2-bisphenyldiborate pinacol ester. The resulting PAF solid exhibited strong fluorescence emission with a quantum yield of 18.31%, showing excellent light and heat stability. Because the lowest unoccupied molecular orbital (LUMO) of LNU-23 was higher than that of the nitro compounds, there was an energy transfer from the excited LNU-23 to the analyte, leading to the selective fluorescence quenching with a limit of detection (LOD) ≈ 1.47 × 10−5 M. After integrating the luminescent PAF powder on the paper by a simple dipping method, the indicator papers revealed a fast fluorescence response to gaseous nitrobenzene within 10 s, which shows great potential in outdoor fluorescence detection of nitro compounds.  相似文献   
43.
Graphite anodes are well established for commercial use in lithium-ion battery systems. However, the limited capacity of graphite limits the further development of lithium-ion batteries. Hard carbon obtained from biomass is a highly promising anode material, with the advantage of enriched microcrystalline structure characteristics for better lithium storage. Tannin, a secondary product of metabolism during plant growth, has a rich source on earth. But the mechanism of hard carbon obtained from its derivation in lithium-ion batteries has been little studied. This paper successfully applied the hard carbon obtained from tannin as anode and illustrated the relationship between its structure and lithium storage performance. Meanwhile, to further enhance the performance, graphene oxide is skillfully compounded. The contact with the electrolyte and the charge transfer capability are effectively enhanced, then the capacity of PVP-HC is 255.5 mAh g−1 after 200 cycles at a current density of 400 mA g−1, with a capacity retention rate of 91.25%. The present work lays the foundation and opens up ideas for the application of biomass-derived hard carbon in lithium anodes.  相似文献   
44.
Self-healing alginate hydrogels play important roles in the biological field due to their biocompatibility and ability to recover after cracking. One of the primary targets for researchers in this field is to increase the self-healing speed. Sodium alginate was oxidized, generating aldehyde groups on the chains, which were then crosslinked by poly(amino) amine (PAMAM) via Schiff base reaction. The dendritic structure was introduced to the alginate hydrogel in this work, which was supposed to promote intermolecular interactions and accelerate the self-healing process. Results showed that the hydrogel (ADA-PAMAM) formed a gel within 2.5 min with stable rheological properties. Within 25 min, the hydrogel recovered under room temperature. Furthermore, the aldehyde degree of alginate dialdehyde with a different oxidation degree was characterized through gel permeation chromatograph aligned with multi-angle laser light scattering and ultraviolet (UV) absorption. The chemical structure of the hydrogel was characterized through Fourier transform infrared spectroscopy and UV-vis spectra. The SEM and laser scanning confocal microscope (CLSM) presented the antibiotic ability of ADA-PAMAM against both S. aureus and E. coli when incubated with 10−7 CFU microorganism under room temperature for 2 h. This work presented a strategy to promote the self-healing of hydrogel through forming a dendritic dynamic crosslinking network.  相似文献   
45.
Due to their high sensitivity to temperature and humidity, the applications of polylactic acid (PLA) products are limited. The stereo-complexation (SC) formed by poly(L-lactic acid) (PLLA) and its enantiomer poly(D-lactic acid) (PDLA) can effectively improve the heat resistance and hydrolysis resistance of PLA products. In this work, the blended melt-spinning process of PLLA/PDLA was carried out using a polyester fiber production line to obtain PLA fiber with a complete SC structure. The effects of high-temperature tension heat-setting on the crystalline structure, thermal properties, mechanical properties, and hydrolysis resistance were discussed. The results indicated that when the tension heat-setting temperature reached 190 °C, the fiber achieved an almost complete SC structure, and its melting point was 222.5 °C. An accelerated hydrolysis experiment in a 95 °C water bath proved that the SC crystallites had better hydrolysis resistance than homocrystallization (HC). The monofilament strength retention rate of SC−190 fiber reached as high as 78.5% after hydrolysis for 24 h, which was significantly improved compared with PLLA/PDLA drawn fiber.  相似文献   
46.
47.
Acute lung injury (ALI) is a kind of lung disease with acute dyspnea, pulmonary inflammation, respiratory distress, and non-cardiogenic pulmonary edema, accompanied by the mid- and end-stage characteristics of COVID-19, clinically. It is imperative to find non-toxic natural substances on preventing ALI and its complications. The animal experiments demonstrated that Lentinus edodes polysaccharides (PLE) had a potential role in alleviating ALI by inhibiting oxidative stress and inflammation, which was manifested by reducing the levels of serum lung injury indicators (C3, hs-CRP, and GGT), reducing the levels of inflammatory factors (TNF-α, IL-1β, and IL-6), and increasing the activities of antioxidant enzymes (SOD and CAT) in the lung. Furthermore, PLE had the typical characteristics of pyran-type linked by β-type glycosidic linkages. The conclusions indicated that PLE could be used as functional foods and natural drugs in preventing ALI.  相似文献   
48.
Cancer is a leading cause of death worldwide, with an increasing mortality rate over the past years. The early detection of cancer contributes to early diagnosis and subsequent treatment. How to detect early cancer has become one of the hot research directions of cancer. Tumor biomarkers, biochemical parameters for reflecting cancer occurrence and progression have caused much attention in cancer early detection. Due to high sensitivity, convenience and low cost, biosensors have been largely developed to detect tumor biomarkers. This review describes the application of various biosensors in detecting tumor markers. Firstly, several typical tumor makers, such as neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), prostate-specific antigen (PSA), squamous cell carcinoma antigen (SCCA), carbohydrate, antigen19-9 (CA19-9) and tumor suppressor p53 (TP53), which may be helpful for early cancer detection in the clinic, are briefly described. Then, various biosensors, mainly focusing on electrochemical biosensors, optical biosensors, photoelectrochemical biosensors, piezoelectric biosensors and aptamer sensors, are discussed. Specifically, the operation principles of biosensors, nanomaterials used in biosensors and the application of biosensors in tumor marker detection have been comprehensively reviewed and provided. Lastly, the challenges and prospects for developing effective biosensors for early cancer diagnosis are discussed.  相似文献   
49.
50.
The adsorption of antibiotics on minerals is an important process in their environment behavior. The adsorption behavior of antibiotics on iron-containing minerals and the effect of co-existing cations and anions were studied in this work. Magnetite, hematite, goethite and kaolin were selected as the representative minerals and characterized by SEM, XRD and BET. A total of eight antibiotics, including three quinolones, three sulfonamides and two mycins were chosen as the research targets. Results showed a higher adsorption amount of quinolones than that of sulfonamides and mycins on the surface of iron-containing minerals in most mineral systems. The adsorption isotherms of quinolones can be well fitted using the Freundlich models. The effects of five cations and five anions on the adsorption of quinolones were investigated, among which Mg2+, Ca2+, HCO3 and H2PO4 mainly showed significant inhibition on the adsorption, while the effects of K+, Na+, NH4+, Cl, NO3 and SO42− showed less. Natural surface water samples were also collected and used as media to investigate the adsorption behavior of quinolones on iron-containing minerals. The buffering capacity of the natural water kept the reaction solution at circumneutral conditions, and the adsorption amount was mostly promoted in the goethite system (from 0.56~0.78 μmol/g to 0.52~1.43 μmol/g), but was inhibited in the other systems (magnetite: from 1.13~1.33 μmol/g to 0.45~0.76 μmol/g; hematite: from 0.52~0.65 μmol/g to 0.02~0.18 μmol/g; kaolin: from 1.98~1.99 μmol/g to 0.90~1.40 μmol/g). The results in this work help to further understand the transportation and fate of antibiotics in an aqueous environment.  相似文献   
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