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1.
Heliyon ; 10(5): e27222, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38486734

ABSTRACT

Zanthoxylum armatum is an economically important tree species. However, well-developed prickles on its stems and leaves pose serious challenges in terms of management and harvesting. To investigate the molecular mechanism underlying prickle development, we sequenced different stages of prickle morphological development and transcriptomes of different tissues in the root tips (Gen), leaf buds (Ya), and fruits of Z. armatum. The results revealed that proteins related to cell division and genes related to the growth hormone signaling pathway were highly expressed in the prickle just protrusion (PC1). In addition, a high expression of lignin biosynthesis genes was observed during the developmental onset of lignification (PC2) and prickle lignification (PC3). These findings indicate that phenylpropanoid biosynthesis and plant hormone signal transduction are key pathways for the completion of lignification development in the prickle. During prickle development, ZaMYB2 and ZaWRKY3 were significantly upregulated in PC2 and PC3, suggesting their possible involvement in prickle development. Transcriptome and qRT-PCR analyses revealed differential gene expression of zaPAL3, za4CLL1, zaCOMT1, ZaWRKY3, and ZaCCD31 in the Gen, Ya, newly formed fruit (ZaF1), newly oil-spotted fruits (ZaF2), PC1, PC2, and PC3 of Zarmatum. zaCCD31 was highly expressed in leaf buds, whereas Za4CLL1 was highly expressed in root tips. During the lignification of prickles, the relative expression of genes including zaMYB2 increased gradually; however, the relative expression of zaCCD31 decreased during this process. Therefore, we inferred that these genes might be closely related to prickle development. Notably, zaMYB2 was expressed at higher levels in PC2 and PC3 than in PC1 and was not expressed in Gen, Ya, ZaF1, and ZaF2. Therefore, zaMYB2 is a key gene involved in prickle development of Z. armatum that exhibited tissue-specific expression. This study establishes a foundation for future analyses of the molecular mechanism underlying prickle development in Z. armatum.

2.
Mar Pollut Bull ; 199: 116011, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38183836

ABSTRACT

Silica aerogels are attractive oil-absorbing agents due to their low density, high porosity. However, how to discharge the oil which adsorbed by silica aerogels is a difficult issue. To address this challenge, new separation strategies with high efficiency are needed. In this study, we prepared the temperature and pH dual response flexible silica aerogel have temperature response and pH response effect, which can change its wettability by adjusting temperature or pH. On the one hand, the temperature and pH responsive flexible silica aerogel can be used to adsorb water at the temperature below 34.73 °C or pH > 7. On the other hand, it can adsorb oil at a temperature above 34.73 °C or pH < 7. The automatic desorption of oil can be achieved without consuming additional energy and damaging the pore structure. Therefore, the sample could continuously adsorb and filtrate efficiently and realize the recovery of oil and adsorption materials.


Subject(s)
Silicon Dioxide , Wettability , Temperature , Silicon Dioxide/chemistry , Gels/chemistry , Hydrogen-Ion Concentration
3.
Gels ; 9(9)2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37754420

ABSTRACT

Using silica as the precursor, and methyltrimethoxysilane and dimethyldimethoxysilane as the silicon sources, a super-flexible hydrophobic lipophilic gel solid was prepared via hydrolysis, drying, solvent replacement, and atmospheric-pressure drying. The characterization test showed that the sample had good flexibility, hydrophobicity, an amorphous structure, and a hydrophobic contact angle of 137°. Through the adsorption separation experiment, it was concluded that the adsorption separation rate of aerogel to oil substances is related to the viscosity of the oil substances. The hydrophobic and oleophilic properties of flexible silicon aerogel materials can be applied to many aspects, such as crude oil leakage and kitchen waste oil recovery, with broad future development prospects and great research significance.

4.
ACS Appl Mater Interfaces ; 15(10): 13270-13280, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36877582

ABSTRACT

Inorganic perovskites have received much attention due to their stability and high performance in luminescence, photoelectric conversion, and photodetection. However, perovskite optoelectronic devices prepared by the solution technique are still suffering from time-consuming and complex operations. In this paper, a single-crystal perovskite-based photodetector (PD) is prepared by very fast one-step deposition of synthesizing microplatelets (MPs) on the electrode directly. The saturated precursor is carefully optimized by adding appropriate antisolvent chlorobenzene (CB) to fabricate the MPs with their PL wavelength ranging from 418 to 600 nm. Furthermore, the PDs with a low dark current on order of nanoangstroms, high responsivity and detectivity of up to 10.7 A W-1 and 1012 Jones, respectively, and an ultrafast response rate featured by 278/287 µs (rise/decay time) are achieved. These all-inorganic perovskite PDs with a simple fabricating process and tunable detection wavelength meet the evolution tendency of PDs toward low cost and high performance, which is a high-profile strategy to realize high-performance perovskite PDs.

5.
Gels ; 9(2)2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36826333

ABSTRACT

The application of silica aerogel has been limited because of its poor mechanical properties. In order to expand the application scope of silica aerogel, this study fabricated an ultra-flexible conductive silica aerogel as a multiparameter sensor. The sample is fabricated by introducing poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) on a base of ultra-flexible silica aerogel, which was prepared by a diene synthesis reaction at atmospheric pressure. The pressure, temperature, and humidity can be converted into electrical signals. The pressure sensitivity can reach up to 54.88 kPa-1, and the detection limit is as low as 5 Pa. The temperature resolution is up to 0.1 K, and the response time of humidity is within 4 s. More importantly, the developed multiparameter sensor can be self-powered to realize multiparameter sensing of pressure, temperature, and humidity. The ultra-flexible conductive silica aerogel is a promising candidate for monitoring human activities and fire-affected areas.

6.
J Colloid Interface Sci ; 630(Pt A): 544-555, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36270175

ABSTRACT

Efforts to develop a green, inexpensive and effective adsorbent are crucial for eliminating antibiotics in polluted water. The sorption capacity of the as-prepared polyvinyl alcohol (PVA)-assisted cellulose nanocrystals/SiO2 (CNCs/SiO2) composite aerogel to ciprofloxacin (CIP) rises with the increase of temperature and initial concentration. Reverse trend of sorption capacity can be found when increasing the adsorbent dosage of adsorbent. The optimal pH value for the sorption is proved to be 4. It's found in the uniaxial compression test that the maximum load that PVA-assisted aerogels can withstand is nearly 100 times than that of non-PVA aerogels. Sorption results confirm that the Pseudo-second order (R2 = 0.9885) and Langmuir models (R2 = 0.9959) fit well to sorption kinetics and equilibrium data, respectively. The rate constant differs from the initial concentration of CIP according to the Pseudo-second order model. The composite aerogel sorption capacity of Langmuir (qmax) for CIP was 163.34 mg·g-1. The thermodynamic studies showed that the sorption process is endothermic with the value of enthalpy change of 41.032 kJ/mol. Hydrogen bonding, π-π interaction, hydrophobic and electrostatic interactions are the dominant mechanisms of CIP sorption by the PVA-assisted CNCs/SiO2 composite aerogel.


Subject(s)
Ciprofloxacin , Polyvinyl Alcohol , Ciprofloxacin/chemistry , Polyvinyl Alcohol/chemistry , Silicon Dioxide/chemistry , Adsorption , Kinetics , Hydrogen-Ion Concentration
7.
Materials (Basel) ; 15(22)2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36431557

ABSTRACT

Skeletal muscles exhibit excellent properties due to their well-developed microstructures. Taking inspiration from nature that thick filaments and thin filaments are linked by "cross-bridges", leading to good stability and ion transport performance of muscles. In this work, extracted poplar lignin and microcrystalline cellulose (MCC) were connected by biomimetic covalent bonds, akin to biological muscle tissue, in which isophorone diisocyanate was used as the chemical crosslinking agent. Then, poplar lignin-MCC was mixed with polyacrylonitrile to serve as the precursor for electrospinning. The results show that due to the effective covalent-bond connection, the precursor fibers possess excellent morphology, smooth surface, good thermal stability, and high flexibility and toughness (average elongation-at-break is 51.84%). Therefore, after thermal stabilization and carbonization, derived lignocellulose-based carbon fibers (CFs) with a reduced cost, complete fiber morphology with a uniform diameter (0.48 ± 0.22 µm), and high graphitization degree were obtained. Finally, the electrodes fabrication and electrochemical testing were carried out. The results of electrochemical impedance spectroscopy (EIS) indicate that the Rs and Rct values of CFs supercapacitors are 1.18 Ω and 0.14 Ω, respectively. Results of cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) suggest that these CFs demonstrate great application potential in electrochemical materials.

8.
Polymers (Basel) ; 14(13)2022 Jun 26.
Article in English | MEDLINE | ID: mdl-35808637

ABSTRACT

At present, high-performance carbon fibers (CFs) are mainly produced from petroleum-based materials. However, the high costs and environmental problems of the production process prompted the development of new precursors from natural biopolymers. This review focuses on the latest research on the conversion of natural lignocellulosic biomass into precursor fibers and CFs. The influence of the properties, advantages, separation, and extraction of lignin and cellulose (the most abundant natural biopolymers), as well as the spinning process on the final CF performance are detailed. Recent strategies to further improve the quality of such CFs are discussed. The importance and application of CFs in sports equipment manufacturing are briefly summarized. While the large-scale production of CFs from natural lignocellulosic biomass and their applications in sports equipment have not yet been realized, CFs still provide a promising market prospect as green and low-cost materials. Further research is needed to ensure the market entry of lignocellulosic biomass-based CFs.

9.
Sensors (Basel) ; 22(12)2022 Jun 16.
Article in English | MEDLINE | ID: mdl-35746318

ABSTRACT

Plasmonic photodetection based on the hot-electron generation in nanostructures is a promising strategy for sub-band detection due to the high conversion efficiencies; however, it is plagued with the high dark current. In this paper, we have demonstrated the plasmonic photodetection with dark current suppression to create a Si-based broadband photodetector with enhanced performance in the short-wavelength infrared (SWIR) region. By hybridizing a 3 nm Au layer with the spherical Au nanoparticles (NPs) formed by rapid thermal annealing (RTA) on Si substrate, a well-behaved ITO/Au/Au NPs/n-Si Schottky photodetector with suppressed dark current and enhanced absorption in the SWIR region is obtained. This optimized detector shows a broad detection beyond 1200 nm and a high responsivity of 22.82 mA/W at 1310 nm at -1 V, as well as a low dark current density on the order of 10-5 A/cm2. Such a Si-based plasmon-enhanced detector with desirable performance in dark current will be a promising strategy for realization of the high SNR detector while keeping fabrication costs low.

10.
PeerJ ; 10: e13541, 2022.
Article in English | MEDLINE | ID: mdl-35722254

ABSTRACT

Objective: Time perception is a critical point for curling athletes to have in order to successfully complete interactions between themselves and their environment. Exploring the relationship between the accuracy of duration judgment and curling athletes' performance is helpful to reveal the influencing factors on their performance and to provide a reference for the training of athletes' delivery performance. Methods: Thirty curling athletes and 30 non-athletes were recruited as participants. Using 3D modeling technology, curling videos of different situations were presented to the participants as stimulus information, and the participants were required to complete the duration judgment task. The neural activation of the participants during the entire process of duration judgment was recorded using electroencephalogram (EEG) equipment. The performance of the 30 curlers participating in the experiment was measured. Variance analyses were conducted on the collected behavioral and EEG data, and correlation and regression analyseswere conducted between behavioral data and delivery performance. Results: The accuracy of the distance judgment of curlers was higher than that of non-curlers (P < 0.05). In the stimulus video presentation stage, the power in the alpha band of curlers was higher than that of non-athletes (P < 0.05). In the task decision stage, the power in the alpha band of curlers was higher than that of non-athletes (P < 0.05), and the power in the theta band was higher than that of non-athletes (P < 0.05). There was a correlation between the accuracy of the curlers' perception of specific situational time intervals and the accuracy of delivery (P < 0.05). Regression analysis results were y = 3.422 + 1.415x. Conclusion: The accuracy of curling athletes' duration judgment is high in a specific situation. There is a correlation between the accuracy of duration judgment and delivery performance in a specific situation: the higher the accuracy of specific duration perception, the higher the performance accuracy of delivery. The cognitive strategies adopted by curlers differ from those adopted by non-athletes in the completion of duration judgment. Specifically, in a specific situation, fewer attention resources are utilized in the stimulus presentation and decision-making stages, while more memory resources are utilized in the decision-making stage to ensure higher accuracy of interval judgment. This study provides a new idea for exploring the causes of curling athletes' excellent technical performance and provides a reference for future curling research on competition training practice. Given the limitations of mobile EEG devices in this study, future studies can measure neural activity during actual delivery preparation and execution in an environment of high ecological validity to obtain more direct evidence.


Subject(s)
Athletic Performance , Time Perception , Humans , Judgment , Athletes , Electroencephalography
11.
Sci Rep ; 12(1): 7681, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35538226

ABSTRACT

Mechanically flexible optoelectronic devices and systems can enable a much broader range of applications than what their rigid counterparts can do, especially for novel bio-integrated optoelectronic systems, flexible consumer electronics and wearable sensors. Inorganic semiconductor could be a good candidate for the flexible PD when it can keep its high performance under the bending condition. Here, we demonstrate a III-V material-based flexible photodetector operating wavelength from 640 to 1700 nm with the high detectivity of 5.18 × 1011 cm‧Hz1/2/W and fast response speed @1550 nm by using a simply top-to-down fabrication process. The optoelectrical performances are stable as the PDs are exposed to bending cycles with a radius of 15 mm up to 1000 times. Furthermore, the mechanical failure mode of the PD is also investigated, which suggests that the cracking and delamination failure mode are dominant in bending up and bending down direction, respectively. Such a flexible III-V material-based PD and design with stable and high performance could be a promising strategy for the application of the flexible broad spectrum detection.

12.
Materials (Basel) ; 15(9)2022 Apr 21.
Article in English | MEDLINE | ID: mdl-35591340

ABSTRACT

High-temperature nitridation is commonly thought of as a necessary process to obtain N-polar GaN films on a sapphire substrate. In this work, high-quality N-polar GaN films were grown on a vicinal sapphire substrate with a 100 nm high-temperature (HT) AlN buffer layer (high V/III ratio) and without an intentional nitriding process. The smallest X-ray full width at half maximum (FWHM) values of the (002)/(102) plane were 237/337 arcsec. On the contrary, N-polar GaN film with an intentional nitriding process had a lower crystal quality. In addition, we investigated the effect of different substrate treatments 1 min before the high-temperature AlN layer's growth on the quality of the N-polar GaN films grown on different vicinal sapphire substrates.

13.
Rev. psicol. deport ; 31(1): 235-244, mar. 2022. ilus, tab, ^graf
Article in English | IBECS | ID: ibc-206034

ABSTRACT

Because of the complexity of the factors affecting the quality of teaching has obvious, lead to the larger error in the results of the assessment. Therefore, put forward the physical education teaching quality comprehensive evaluation model based on multivariate data research. Using the analytic hierarchy process (AHP) to build the physical teaching quality evaluation mechanism, based on the relative importance of data, establish compound consistency check of judgment matrix. The weights were assigned according to the importance of the data, and the weighted results were equally divided by the method of pulling apart grades. Finally, the physical education teaching quality was evaluated based on AHP-ISD model. The experimental results show that the accuracy of the method can reach more than 97%, which is obviously better than the method of comparison(AU)


Subject(s)
Humans , Data Analysis , Teaching , Physical Education and Training , Laboratory and Fieldwork Analytical Methods , Benchmarking , Educational Measurement
14.
ACS Omega ; 7(3): 2718-2724, 2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35097269

ABSTRACT

The kinetics of high-temperature H2S removal over Mn/Al sorbents prepared by co-precipitation method was investigated in a fixed-bed reactor using a deactivation model. The initial sorption rate constant (k 0), deactivation rate constant (k d), apparent activation energy (E a), and deactivation energy (E d) were obtained. The k 0 and k d values of Mn/Al sorbents are much higher than those of pure Mn2O3. This indicates that Mn/Al sorbents have higher reactivity on the removal of H2S and less diffusion resistance caused by the formation of the sulfided product. The E a and E d values for the sorbent with the Mn content (wt %) of 35.4% are 38.18 and 31.05 kJ/mol, respectively. The deactivation model gives excellent predictions for the H2S breakthrough curves in the sulfidation-regeneration process.

15.
Opt Lett ; 47(23): 6173-6176, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-37219200

ABSTRACT

Polarization detection in the short-wave infrared (SWIR) region presents broad applications in target-background contrast enhancement, underwater imaging, material classification, etc. A mesa structure can prevent electrical cross talk due to its intrinsic advantages, making it potentially suited to meet the need for manufacturing smaller-sized devices to save cost and shrink volume. In this Letter, mesa-structured InGaAs PIN detectors with a spectral response ranging from 900 nm to 1700 nm and a detectivity of 6.28 × 1011 cm·Hz1/2/W at 1550 nm and -0.1 V bias (room temperature) have been demonstrated. Furthermore, the devices with subwavelength gratings in four orientations show obvious polarization performance. Their extinction ratios (ERs) can reach 18:1 at 1550 nm and their transmittances are over 90%. Such a polarized device with a mesa structure could realize miniaturized SWIR polarization detection.

16.
ACS Omega ; 6(44): 29459-29470, 2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34778618

ABSTRACT

In this paper, an improved heat exchanger network (HEN) synthesis method based on the comprehensive learning particle swarm optimizer algorithm (CLPSO) is proposed to synthesize HENs without stream splits. Compared with the standard particle swarm algorithm, CLPSO employs a novel learning strategy that preserves the diversity of the swarm to discourage premature convergence. However, while the algorithm's global exploration capability is enhanced, the local search capability decreases and the convergence speed becomes slow. In addition, the solution quality of CLPSO is largely determined by the randomly generated particles' best previous position (pbest) during initialization. Hence, the solution may be unstable due to different pbest. For the abovementioned considerations, this paper proposes a new HEN initialization and renovation method to improve the quality of pbest, reduce the initial cost, and retain the obtained optimization results as much as possible in the optimization process to speed up the convergence of the algorithm. Four typical cases are simulated to verify the effectiveness of the proposed method. This method only needs a single-level optimization algorithm to obtain high-quality solutions, which will give it a bright prospect in research and application.

17.
Opt Express ; 29(4): 5993-5999, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33726130

ABSTRACT

The photonic crystal (PC) has been demonstrated to be very effective in improving the extraction efficiency of light-emitting diodes (LEDs). In this paper, high-brightness AlGaInP-based vertical LEDs (VLEDs) with surface PC (SPCLED) and embedded PC (EPCLED) were successfully fabricated. Compared with normal LED (NLED), photoluminescence intensities of SPCLED and EPCLED have been improved up to 30% and 60%, respectively. And the reflection patterns of SPCLED and EPCLED were periodic bright points array, showing the ability to control light in PC. Electroluminescent measurements show that three kinds of LEDs have similar threshold voltages. Simultaneously, the light output power (LOP) of SPCLED and EPCLED has been improved up to 24% and 11% at 200 mA, respectively, in comparison to NLEDs. But the LOP decays earlier for EPCLED due to the excessive heat production. Furthermore, it is demonstrated that the SPCLED and EPCLED luminous uniformity is better. This kind of high brightness PCLED is promising in improving the properties of all kinds of LEDs, especially mini LEDs and micro LEDs.

18.
J Colloid Interface Sci ; 583: 128-138, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32980682

ABSTRACT

A series of boehmite microspheres with highly effective adsorption performance for Congo red (CR) were successfully prepared via amides assisted hydrothermal method at 180 °C. Effects of dosages and hydrolysates of N,N-dimethylformamide (DMF), amides species including DMF, N-methylformamide (MF) and formamide (FA), and reaction times on their physicochemical properties were studied in detail. It was found that increase on their crystallinity and shell thickness results from the different hydrolysis rates of the amides; amorphous alumina hydrate, boehmite core-shell structure and hollow microspheres were obtained at hydrothermal times of 60, 140 and 360 min, respectively due to the Ostwald ripening. Especially, dimethylamine (DMA) as a hydrolysate of DMF, can effectively regulate the morphologies of the boehmites together with the sulfate ions, and make their pore sizes distribution (PSD) centering at 3-4 nm. Importantly, the boehmite microspheres with specific surface area of 221.3 m2/g shows the maximum adsorption capacity of 847.5 mg/g for CR calculated from Langmuir isotherm model, and its adsorption amount reached a high value of 484.1 mg/g at 60 min due to the mentioned PSD. This template-free hydrothermal method using DMF as precipitant provides an alternative approach for preparing high-performance hydrated alumina for environmental applications.

19.
J Nanosci Nanotechnol ; 21(2): 1161-1168, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33183457

ABSTRACT

Because some asthma patients have different types of inflammatory cells in their bodies, they cannot get relief with traditional drugs. However, the nano drug delivery system can realize efficient drug delivery, inflammatory cells and intracellular targeting, and the apoptosis of inflammatory cells. This article aims to comprehensively evaluate the effects of montelukast sodium combined with graphene oxide nanomaterials on improving the clinical symptoms and airway inflammation of children with bronchial asthma, with a view to further improving the clinical treatment of children with bronchial asthma. The results show that montelukast sodium can improve lung function in patients with asthma, and also has important effects such as anti-inflammatory and regulating immune function. After exposure to graphene oxide, the level of oxidative stress in mice increased with brightness and humidity, demonstrating the role of T oxidative stress in the development of asthma. In addition, nanocarriers assist co-loaded drugs to deepen and enrich the pulmonary inflammation site, further achieving effective mitochondrial targeted drug delivery, thereby enhancing the inhibitory effect of anti-apoptotic proteins, leading to inflammatory cell apoptosis.


Subject(s)
Anti-Asthmatic Agents , Asthma , Nanostructures , Quinolines , Acetates/pharmacology , Acetates/therapeutic use , Animals , Anti-Asthmatic Agents/therapeutic use , Asthma/chemically induced , Asthma/drug therapy , Cyclopropanes , Graphite , Humans , Mice , Quinolines/pharmacology , Sulfides
20.
ACS Omega ; 5(20): 11361-11368, 2020 May 26.
Article in English | MEDLINE | ID: mdl-32478224

ABSTRACT

The primary aim of this study is to understand the effect of metal oxide flux on the fusibility of high-calcium coal ash. Based on the decomposition rate, the evolution of mineral matters in high-calcium coal has been investigated. The ash fusion temperatures of samples are measured by adding different flux Al2O3, Na2O, K2O, MgO, and TiO2. The results show that Na2O is the most effective in lowering ash fusion temperatures and its flow temperature could be 110 °C lower than that of the original ash. FactSage is used to calculate the proportion of solid phase and the mineral compositions as a function of the ash compositions and temperature. With the increase of Na2O, mineral matters with a low melting point form in the mixture. Furthermore, the decomposition rate of mineral matters increases in the first stage. The phase diagrams and relative mineral variation illustrate that the mineral and the decomposition rate variations are the main reasons for the change of ash fusion temperatures.

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