查找使用阿拉丁产品的科研文献

Construction of a novel Mott-Schottky heterostructure gas sensor g-C3N4/SnO2 with layered nanorods array for high-sensitivity acetone detection

Yanping Zhao,Xuxia Shai,Qihang Zhou,Kaiyuan Shen

Developing exhaled acetone sensors with high performance can be effectively applied to the medical diagnosis and the health monitoring. Herein, a two-dimensional (2D) layered graphitic carbon nitride (g-C 3 N 4 ) with tunable electronic structure, abundant edge sites, and high stability is proposed, and it is further coupled with stannic oxide (SnO 2 ) by one-step hydrothermal approach to construct a Mott-Schottky heterostructure with layered nanorods array. The exceptional response of the as-fabricated g-C 3 N 4 /SnO 2 gas sensor to 50 ppm acetone at 100 °C is four times higher than that of the pristine SnO 2 sensor. Additionally, the g-C 3 N 4 /SnO 2 sensor's remarkable selectivity, long-term stability against acetone gas, and detection limit of 250 ppb are exhibited. The unique hierarchical design and the Mott-Schottky heterostructure creation which validated by electrochemical study, may be in charge of the enhanced acetone sensing capabilities of g-C 3 N 4 /SnO 2 gas sensor. This work will provide a concise and effective avenue to construct hierarchical composite with Mott-Schottky heterostructure for high-performance acetone gas sensor.

Phase change composite materials of sodium alginate-SiO2 aerogel loaded with sodium sulfate decahydrate for cementing of natural gas hydrate layers

Jingxuan Cai,Qiang Ren,Sen Liu,Xuerui Wang,Chunmei Zhang,Kaiyuan Mei,Xiaowei Cheng

Currently, the encapsulated organic phase change materials (PCMs) used in cementing slurries for NGH layers have problems such as difficulty in realizing applications, poor compatibility with cement slurries after leakage, and contamination of the environment at the bottom of the well. Furthermore, there is a dearth of perceptive investigation about the impact of PCMs on the hydration mechanism of cement. This study presents a new idea of using inorganic hydrated salt PCMs to control the heat released of cementing slurries during the hydration process. For the first time, sodium sulfate decahydrate-type composite inorganic hydrated salt PCMs (FH) loaded with SA-SiO 2 were synthesized and analyzed. The effect of FH on cement hydration mechanism was investigated and the changes of cement hydration products were analyzed qualitatively and quantitatively. The results showed the phase transition temperature of FH varied between 20.83 and 43.45 ℃, accompanied with a significant latent heat of phase change of 117.93 J/g. This attribute has the capacity to greatly reduce the rise in temperature during the process of cement hydration and the overall total release of heat. FH did not modify the cement hydration mechanism, but it extended the NG stage and reduced the hydration effect of the I stage, resulting in an increased level of hydration. FH improves the hydration procedure for cement, resulting in an augmented production of calcium-silicate-hydrate (C-S-H) compounds and enhances the compaction and arrangement the C-S-H. The inclusion of FH in the cement slurry did not lead to the dissociation of NGH during the hydration process.

Synergistic Effects of NO/H2S Gases on Antibacterial, Anti-inflammatory, and Analgesic Properties in Oral Ulcers Using a Gas-Releasing Nanoplatform

Yuanqi Chen,Kezheng Lei,Yinxi Li,Zhixiang Mu,Tengda Chu,Jiajun Hu,Bairui Zeng,Yi Wang,Jianliang Shen,Xiaojun Cai,Tianpeng Shi,Hui Deng

Oral mucosal wounds are more prone to inflammation due to direct exposure to various microorganisms. This can result in pain, delayed healing, and other complications, affecting patients' daily activities such as eating and speaking. Consequently, the overall quality of life for patients is significantly reduced. To address these challenges, we developed a multifunctional therapeutic nanoplatform, DATS@Arg-EA-SA, through the self-assembly of guanidinated dendritic peptides (Arg-EA-SA) that encapsulate diallyl trisulfide (DATS), a hydrogen sulfide (H 2 S) donor. The guanidine-rich surface of DATS@Arg-EA-SA efficiently neutralizes reactive oxygen species (ROS) in the ulcer microenvironment, generating nitric oxide (NO), which acts as the primary antimicrobial agent by disrupting bacterial membranes. Concurrently, the presence of glutathione triggers the release of H 2 S from DATS, providing supplementary antibacterial support. DATS@Arg-EA-SA effectively kills all bacteria, achieving results comparable to those of penicillin, a classical antibiotic. Moreover, it demonstrates superior sterilization efficacy against drug-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), significantly outperforming penicillin. Following the initial antimicrobial phase, the nanoplatform transitions into an anti-inflammatory stage. H 2 S, in synergy with NO, facilitates the conversion of M1 macrophages to M2 macrophages, thereby reducing the expression of inflammatory factors. Importantly, the combination of H 2 S and NO provides effective analgesia by downregulating the expression of TRPV1 and TRPV4, thus restoring normal dietary behaviors and improving the overall quality of life. This system ultimately promotes collagen fiber deposition and accelerates the re-epithelialization of the ulcer wound, positioning DATS@Arg-EA-SA as a promising gas-delivery nanoplatform for rapid wound repair in the clinical treatment. Statement of Significance Oral mucosal wounds are highly susceptible to microbial infections, leading to inflammation, pain, delayed healing, and a significant decline in quality of life. We developed a multifunctional therapeutic nanoplatform (DATS@Arg-EA-SA) via the self-assembly of guanidinated dendritic peptides encapsulating the H 2 S donor DATS, which exhibited antibacterial, anti-inflammatory, and analgesic properties. In the oral ulcer microenvironment, DATS@Arg-EA-SA generates substantial NO under elevated ROS levels, while glutathione triggers the controlled release of H 2 S. NO disrupts bacterial membranes as the primary antibacterial agent, with H 2 S providing synergistic antibacterial effects. Furthermore, H 2 S and NO synergistically promote the transformation of M1 to M2 macrophages, attenuating inflammation. Importantly, the combined action of H 2 S and NO alleviates pain by downregulating TRPV1 and TRPV4, supporting the restoration of normal dietary behavior and improving quality of life.

Gas stripping coupled with in-situ oxidation assisted microwave remediation of contaminated soil for efficient removal of polycyclic aromatic hydrocarbons (PAHs)

Lei Wu,Hongyan Wu,Qiusi Wen,Jun Zhou,Ahmed M. Aljuwayie,Poh Wai Chia,Gan Ye,Qiuli Zhang,Rock Keey Liew,Su Shiung Lam

Thermal desorption technology at low temperatures has been extensively researched. However, the challenge remains in maintaining soil ecological function while effectively removing PAHs from contaminated soil using this method. Based on the gas hammer fragmentation concept, this study presents the strategy of gas stripping (steam extraction) coupled with microwave remediation. A multifunctional bluecoke-based modifier (MnO 2 /KHCO 3 @BC) was prepared followed by an investigation on the removal effect, soil characteristics and remediation mechanism of MnO 2 /KHCO 3 @BC-assisted microwave remediation of pyrene (PAHs model) contaminated soil. The research findings indicate that MnO 2 /KHCO 3 @BC is more effective in generating oxygen vacancies, facilitating surface electron transfer , and enhancing the oxidation effect of ROS on pyrene compared to KHCO 3 @BC and MnO 2 @BC. Despite having slightly inferior electromagnetic properties to BC, MnO 2 /KHCO 3 @BC could achieve a microwave remediation temperature of approximately 300 °C under optimal experimental conditions. MnO 2 /KHCO 3 @BC demonstrated remarkable pyrene removal efficiency with a maximum removal rate of 98.34%, making it an ideal candidate for pyrene remediation. Moreover, the remediated soil exhibited a weakly acidic nature, with a significant decrease in particle size and a substantial increase in potassium content. The study also highlighted a novel synergistic mechanism of ''microwave heating - gas stripping - oxidation,'' which can efficiently remove most of the pyrene adsorbed inside and outside of soil particles and degrade it into low-toxic and small-molecule organic matter, CO 2 , and H 2 O. Overall, the findings of this study could hold potential significance for upcoming endeavours concerning polluted industrial areas.

Experimental Study on the Kinetics of the Natural Gas Hydration Process with a NiMnGa Micro-/Nanofluid in a Static Suspension System

Qiong Wu,Nengyu Lin,Li Li,Feng Chen,Baoyong Zhang,Qiang Wu,Xianfu Xv,Xinyan Wang

Natural gas is a resource-rich clean energy source, and natural gas hydration technology is a promising method for natural gas storage and transportation at present. To realize the rapid generation of hydrates with a high gas storage capacity, in this paper NiMnGa micro/nanoparticles (NMGs) with different mass fractions (0.1 wt%, 1 wt%, 2 wt%) were prepared with 0.05 wt% sodium dodecyl sulfate (SDS) and 1 wt% L-tryptophan to form static suspension solutions of gellan gum, and the methane hydration separation kinetics experiments were carried out under the condition of 6.2 MPa for the SDS-NMG-SNG (SNG) and L-tryptophan-NMG-LNG (LNG) systems. The results showed that the induction time of the systems with NMG micro-/nanoparticles was shortened to different degrees and the gas consumption rate was increased. The best effect was achieved in the SNG system with 1 wt% NMG, and the induction time was shortened by 73.6% compared with the SDS-gellan system (SG). The gas consumption rate of the system with L-tryptophan was better than that of the system with SDS, and the best effect was achieved in the system with 2 wt% NMG. The system with 2 wt% NMG had the best effect, and the problem of foam decomposition did not occur. The analysis concluded that NMG has strong mass transfer and phase-change heat absorption properties, which can significantly improve the kinetics of the natural gas hydrate generation process; L-tryptophan can weaken the diffusion resistance of methane molecules in the suspended static solution, further enhancing the mass transfer of the hydrate generation process. These findings will provide new perspectives regarding the application of phase-change micro-/nanoparticles in methane hydrate generation under static conditions.Keywords:gas hydrate;phase-change nanoparticles;surfactants;static system;kinetic characteristics

Low-temperature co-purification of NOx and Hg0 from simulated flue gas by CexZryMnzO2/r-Al2O3: the performance and its mechanism

Lu Pei,Yue Huifang,Xing Yi,Wei Jianjun,Zeng Zheng,Li Rui,Wu Wanrong

In this study, series of Ce x Zr y Mn z O 2 /r-Al 2 O 3 catalysts were prepared by impregnation method and explored to co-purification of NO x and Hg 0 at low temperature. The physical and chemical properties of the catalysts were investigated by XRD, BET, FTIR, NH 3 -TPD, H 2 -TPR, and XPS. The experimental results showed that 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 yielded higher conversion on co-purification of NO x and Hg 0 than the other prepared catalysts at low temperature, especially at 200–300 °C. 91% and 97% convert rate of NO x and Hg 0 were obtained, respectively, when 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 catalyst was used at 250 °C. Moreover, the presence of H 2 O slightly decreased the removal of NO x and Hg 0 owing to the competitive adsorption of H 2 O and Hg 0 . When SO 2 was added, the removal of Hg 0 first increased slightly and then presented a decrease due to the generation of SO 3 and (NH 4 ) 2 SO 4 . The results of NH 3 -TPD indicated that the strong acid of 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 improved its high-temperature activity. XPS and H 2 -TPR results showed there were high-valence Mn and Ce species in 10% Ce 0.2 Zr 0.3 Mn 0.5 O 2 /r-Al 2 O 3 , which could effectively promote the removal of NO x and Hg 0 . Therefore, the mechanisms of Hg 0 and NO x removal were proposed as Hg (ad) + [O] → HgO (ad), and 2NH 3 /NH 4 + (ad) + NO 2 (ad) + NO (g) → 2 N 2  + 3H 2 O/2H + , respectively. ᅟ

ZnWO4/f-MWCNTs Nanocomposite for H2S Gas Sensor with Fast Response and Recovery: Mechanism Study and Application for Detecting Fish Spoilage

Zhihua Zhao,Shixin Ma,Yao Wang

Hydrogen sulfide (H2S), a characteristic byproduct of sulfur-containing amino acid decomposition during fish spoilage, serves as a critical freshness indicator and poses substantial food safety risks. This study develops a novel H2S gas sensor using a ZnWO4/f-MWCNTs nanocomposite synthesized via one-step hydrothermal method. The incorporated functionalized multiwalled carbon nanotubes (f-MWCNTs) improve the sensing material’s conductivity, dispersion stability, and gas adsorption capacity. XRD, XPS, FTIR, SEM, TEM, and BET analyses verify the composite’s successful synthesis and optimal physicochemical properties. The ZnWO4/f-MWCNTs sensor demonstrates exceptional H2S detection at 120 °C, achieving a response value of 18.67 (Ra/Rg) to 50 ppm of H2S with fast response/recovery times (14 s/30 s) and excellent selectivity against interferents. Real-time monitoring of fish spoilage further confirms its practical utility, highlighting the sensor’s potential for meat freshness assessment and food safety applications.

High Response and Selectivity of the SnO2 Nanobox Gas Sensor for Ethyl Methyl Carbonate Leakage Detection in a Lithium-Ion battery

Huiyu Su,Huimin Yang,Chaofan Ma,Jiahong Tang,Chaoqi Zhu,Xiaoxia Wang,Dawen Zeng

It is well-known that metal-oxide semiconductors (MOS) have significant gas sensing activity and are widely used in harmful gas monitoring in various environments. With the rapid development of new energy vehicles, the monitoring of the gas composition and concentration in LIB has become an effective way to avoid safety problems. However, the study of typical electrolyte solvent detection, such as EMC and DMC detection by the MOS sensor, is still in its infancy. Here, the SnO2 nanoboxes are synthesized by coordination dissolution using cubic Cu2O as the template, and its sensor shows high sensitivity (0.27 to 10 ppb EMC), excellent response (32.46 to 20 ppm EMC), and superior selectivity. Additionally, the sensor possesses fast and clear response to lithium-ion battery (LIB) leakage simulation tests, suggesting that it should be a promising candidate for LIB safety monitors. These sensing performances are attributed to large specific surface area, small grain size, and high size/thickness ratio of nanoboxes. More importantly, DFT calculations confirm the adsorption of EMC on the surface of the SnO2 nanoboxes, and the EMC decomposition processes catalyzed by SnO2 are deduced by in situ FTIR and GC-MS.

High-Performance Biobased Polyesters with High Gas Barrier, Glass Transition Temperature, and Tensile Strength Enabled by Hydrogen Bonds and Flexible Segments

Wei-Qiang Du,Teng Fu,Xing-Liang Li,Yao Li,Cong Deng,Xiu-Li Wang,Yu-Zhong Wang

High-performance biobased polyesters with excellent thermal, mechanical, and gas barrier properties are in demand nowadays, while current design strategies have failed to endow polyesters with such integrated performances synchronously. Herein, we synthesize a series of furan-based copolyesters poly(butylene 4-hydroxy-N-(2-hydroxyethyl)2,5-furandicarboxylate) (PBAnF) containing an amide structure and flexible aliphatic segments in the main chains via condensed polymerization. The resultant copolyester PBA20F records balanced pre-eminent mechanical properties including tensile strength (78.0 MPa) and a large elongation at break (199%) while exhibiting a high glass transition temperature (54 °C) and a good enough gas barrier property. Such integrated excellent performances of copolyesters are ascribed to the combined effects of introduced intermolecular hydrogen bonds and flexible segments. Besides, PBAnFs still display high optical transparency in the visible region. This work provides an innovative design strategy to prepare a new class of advanced furan-based copolyesters with remarkable mechanical, thermal, and gas barrier properties, thus supplying a series of promising high-performance biobased copolyesters for potential packaging applications.

Accuracy improvement of determination of seven minor tobacco alkaloids in mainstream cigarette smoke using analyte protectants by gas chromatography-mass spectrometry

Qiong Guo,Yaqiong Qin,Lining Pan,Fuwei Xie,Shaofeng Liu,Xuehui Sun,Xiaoyu Wang,Junlan Cai,Xiaodong Zhao,Huimin Liu

A bstract Tobacco alkaloids are important precursors of carcinogenic tobacco-specific nitrosamines . Therefore, accurate quantification of tobacco alkaloids is highly important. This study investigates the compensation effects of novel analyte protectants (APs) for matrix effects (MEs) to determine seven minor tobacco alkaloids (nornicotine, myosmine , anabasine , anatabine , nicotyrine , 2,3′-bipyridine, and cotinine) in mainstream cigarette smoke with high accuracy and robustness. By comparing the heights and shapes of the chromatographic peaks before and after the addition of APs to standard solutions prepared in dichloromethane and cigarette smoke solutions, the compensation effects of 12 APs and their combinations on the MEs of seven minor tobacco alkaloids were evaluated, and the best combination of 2-pyridylethylamine (2 mg/mL)+1,2-decanediol (1 mg/mL) was identified. This AP combination could effectively improve the shapes and increase the heights (by 7–371%) of chromatographic peaks for standard solutions prepared in dichloromethane and cigarette smoke solutions. Before the addition of this AP combination, the slope ratios of the calibration curves for two types of standard solutions of the seven target chemicals were 71.4–159.8%, while they were 87.4–105.6% after the addition, indicating that this AP combination reduced the matrix difference between pure solvent and cigarette smoke solution. After adding the AP combination, the standard curves of solutions prepared in dichloromethane showed good linearity ( r 2 ≥ 0.999), the spiked recoveries were between 80.9% and 119.6%, and the inter- and intraday precisions were between 1.5–9.5% and 3.1–8.5%, respectively. Three commercial cigarette samples and one mixed standard solution were also tested under four different instrument working conditions to verify the long-term accuracy and ruggedness of the approach in routine real-world analysis of the method. The results showed that the RSD values were higher (3.5–25.4%) without the AP combination than that (<6.7%) with the AP combination. Because of its high accuracy, precision, and robustness, this method has good practical prospects.

Gas Chromatography-Mass Spectrometric Analysis and Insecticidal Activity of Essential Oil of Aerial Parts of Mallotus apelta (Lour.) Muell.-Arg. (Euphorbiaceae)

XC Liu,XB Chen,ZL Liu

Determination of phthalate acid esters in soybean milk using dispersive liquid–liquid microextraction coupled with gas chromatography and mass spectrometric detection

Songchun Bai,Xinxiu Wang,Fan Hu,Tianlin Wang,Ping Cheng,Zhen Zhou

Dispersive liquid–liquid microextraction (DLLME) was coupled with gas chromatography and mass spectrometric detection for the determination of eight phthalate acid esters (PAEs) in soybean milk. Parameters impacting the extraction efficiencies were optimized including organic solvents to extract PAEs from soybean milk, salt concentrations and organic solvents for DLLME. Under the optimal conditions, limits of detection (LODs) and limits of quantification (LOQs) were in the range of 0.57–0.79 and 1.90–2.63 ng g−1, respectively. Linearities varied in the range of 1–16 000 ng g−1 with the correlation coefficients of 0.9993–0.9998. The precision of the method was 2.9–3.2 in terms of RSD% based on triplicate measurements. The preconcentration factors were in the range of 200–260. The recoveries of eight PAEs were in the range from 79.0 to 110% at three spiked levels. The trace PAEs in five different brands of soybean milk purchased from the market were determined successfully.