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Bile acids (BAs) play important pathophysiological roles in both humans and mammalian animals. Laboratory rats and mice are widely used animal models for assessing pharmacological effects and their underlying molecular mechanisms. However, substantial physiological differences exist in BA composition between humans and murine rodents. Here, we comprehensively compare BA profiles, including primary and secondary BAs, along with their amino acid conjugates, and sulfated metabolites in serum, urine, and feces between humans and two murine rodents. We further analyze the capabilities in gut microbial transform BAs among three species and compare sex-dependent variations within each species. As a result, BAs undergo amidation predominately with glycine in humans and taurine in mice but are primarily unamidated in rats. BA sulfation is a unique characteristic in humans, whereas rats and mice primarily perform multiple hydroxylations during BA synthesis and metabolism. For gut microbial transformed BA capabilities, humans are comparable to those of rats, stronger than those of mice in deconjugation and 7α-dehydroxylation, while humans are weak than those of rats or mice in oxidation and epimerization. Such differences enhance our understanding of the divergent experimental outcomes observed in humans and murine rodents, necessitating caution when translating findings from these rodent species to humans. The analysis of bile acid profiles in biological samples from humans, rats, and mice reveals species-dependent differences as well as sex-dependent differences within each species. [ABSTRACT FROM AUTHOR]

[Display omitted] • ● The CaO 2 @Cu-LA nanocomposite exhibits a crystal structure of CaO 2 and a coordination structure between metal and amino acid. • ● The CaO 2 @Cu-LA possesses the capability of self-generating H 2 O 2. • ● The CaO 2 @Cu-LA generates •OH, O 2 –•, and NO while consuming GSH under acidic conditions. • ● The CaO 2 @Cu-LA interferes with mitochondrial energy production and disrupts the structure of DNA double strands. • ● The CaO 2 @Cu-LA exhibits significant efficacy in eradicating tumor cells both in vitro and in vivo. Chemodynamic therapy (CDT) based on hydroxyl radicals (•OH) to suppress tumor cells is a promising strategy due to its efficacy and safety. Nevertheless, in tumor cells, CDT still faces challenges such as insufficient •OH and weak killing effect of tumor cells under physiological conditions due to inadequate amounts of endogenous hydrogen peroxide (H 2 O 2) and heightened glutathione expression. These challenges limit the therapeutic potential of CDT. To improve the effects of CDT, combination treatment strategies have been developed. Here, we report a rationally designed nanocomposite (CaO 2 @Cu-LA) with self-supplying H 2 O 2 ability from calcium peroxide, and nitric oxide (NO) generation ability from l -arginine. NO molecules not only exhibit a strong killing effect, but also have the potential to transfer into the more cytotoxic substance peroxynitrite anion by reacting with reactive oxygen species. The results showed that CaO 2 @Cu-LA could significantly suppress tumor growth by increasing •OH radicals and NO molecules. Taken together, the strategy developed here provides a good application foreground to yield a remarkable synergistic antitumor effect of CDT and NO gas therapy. [ABSTRACT FROM AUTHOR]

We present a hybrid cavity designed to manipulate lasing modes, consisting of a metal-dielectric core–shell hybrid microcavity fabricated using a simple brush-coating method. Single and multiple modes can be obtained in the proposed laser device by the trade-off between loss and gain. Moreover, we achieve electrically tunable whispering-gallery-mode lasing by employing the thermo-optic effect in the hybrid microcavity. The lasing peak of the modes can be electrically tuned by quantitative control of Joule heating. We measure a tuning rate of 15.3 pm/J for all the lasing peaks. [ABSTRACT FROM AUTHOR]

In this work, a simple, high-throughput, and sensitive analytical method based on surface-enhanced Raman spectroscopy (SERS) and principal component analysis (PCA) was fabricated for simultaneous and rapid determination of three polychlorinated phenols (PCPs) including 2,4-dichlorophenol (2,4-DCP), 2,4,5-trichlorophenol (2,4,5-TCP), and 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP). The aggregated Ag nanoparticles (AgNPs) induced by inorganic salt ions were used as sensitive SERS substrate, and the electromagnetic field distribution of AgNPs with different distances was simulated by finite difference time domain (FDTD) to verify the theory feasibility. The high throughput and rapid detection can be achieved by commercial 96-pore plate. Under the optimum conditions, the linear relationship between the Raman intensity and the concentrations of PCPs was established with satisfied correlation coefficient. The limits of detection (LOD) for 2,4-DCP, 2,4,5-TCP, and 2,3,4,6-TeCP are 0.27 mg L−1, 0.09 mg L−1, and 0.10 mg L−1 by rules of 3σ, respectively. The simultaneous quantitative analysis can be achieved thanks to the independent Raman characteristic peaks of three PCPs. Afterwards, the PCA method was used to eliminate the limitations of overlapping of characteristic Raman peaks in structural analogues of 2,4-DCP, 2,4,5-TCP, and 2,3,4,6-TeCP. The recovery experiments including single PCPs and mixed PCP samples show satisfied recoveries ranging from 85.0 to 113.9% and 80.4 to 114.0% with RSDs in range of 0.4–9.5% and 1.1–10.7%, respectively. The proposed method shows great potentials in rapid, high-throughput, and sensitive monitoring of the contaminants in water and pesticide samples with similar structure. Here, we introduced aggregated Ag nanoparticles (AgNPs) induced by inorganic salt ion for simultaneous, rapid, and sensitive determination of polychlorinated phenols (PCPs) including 2,4-dichlorophenol (2,4-DCP), 2,4,5-trichlorophenol (2,4,5-TCP), and 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) by surface-enhanced Raman spectroscopy (SERS) combined with principal component analysis (PCA). The AgNPs induced by inorganic salt ions were used as sensitive SERS substrate, and the electromagnetic field distribution of AgNPs with different distances was simulated by finite difference time domain (FDTD) to verify the theory feasibility. The PCA method was used to eliminate the limitations of overlapping of characteristic Raman peaks in structural analogues of 2,4-DCP, 2,4,5-TCP, and 2,3,4,6-TeCP. The proposed method shows great potentials in rapid, high-throughput, and sensitive monitoring of the contaminants in water and pesticide samples with similar structure. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s00216-022-03876-0.Correction to: Analytical and Bioanalytical Chemistry (2022) 414:2385–2395https://doi.org/10.1007/s00216-022-03876-0The original article has been corrected.Author Kun Ge should only be affiliated to: School of Chemistry, Sun Yat-sen University, Guangzhou 510006, China.Publisher's NoteSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.By Kun Ge; Yonghui Li; Qiyue Wu and Ying GuReported by Author; Author; Author; Author [Extracted from the article]

• Novel analysis framework for the Green Transition of Urban Land Use. • Long-term, wide-area data reveals temporal and spatial differences in transition. • Focus on the spatial convergence of Green Transition of Urban Land Use. • Regional heterogeneity in the spatial convergence effect. Revealing the spatial differences and the convergence mechanisms of Green Transition of Urban Land Use (GTULU) in the context of industrial integration is of great significance for formulating differentiated industrial development strategies, accelerating the process of industrial integration, and exploring synergistic enhancement paths of GTULU. In this paper, 107 prefecture-level and above cities in the Yangtze River Economic Belt (YREB) are taken as research objects, and the entropy value method, exploratory spatial data analysis model and spatial convergence model are comprehensively applied to analyze the spatio-temporal differences and spatial convergence of the GTULU under the background of industrial integration. The study shows that: (1) from 2003 to 2021, the level of GTULU in the YREB has been increasing, with the mean value growing from 0.09 to 0.14, but there are still significant spatial differentiation and spatial correlation characteristics, and the regional imbalance phenomenon of GTULU is more and more obvious as time goes by. (2) The GTULU of the YREB and its upstream, midstream, and downstream regions all exhibit a temporal evolution characteristic of increasing fluctuations. (3) There is no σ-convergence in GTULU in the YREB and its upstream, middle-stream, and downstream regions. However, there are all significant absolute β convergence and conditional β convergence. Moreover, under the combined influence of government management, technological input, industrial structural adjustment, and spatial impact, the convergence rate of the YREB has significantly accelerated, from 1.98% to 2.31%, and the convergence effect exhibits marked heterogeneity. [ABSTRACT FROM AUTHOR]

The exploitation of natural gas hydrate, an unconventional natural gas, has drawn attention on a global scale due to increasing imbalance between energy supply and demand. Horizontal wells are considered to have a better production performance, while vertical wells have been mostly employed in previous field tests and laboratory research. Therefore, based on the representative properties of three kinds of hydrate reservoirs, a hydrate decomposition model is built to study the gas generation behaviors of various hydrate reservoirs with different horizontal well-spacing strategies in this work. The results show that for Class I hydrate reservoirs, placing the production well near the free gas layer can improve gas generation by 47%, and GWR (gas-water ratio) to 346.0 and maintain higher temperature in hydrate reservoir than that with placing the well in the hydrate reservoir. For Class Ⅱ hydrate reservoirs, placing the producing well away from the free water layer can cut down water production by 92%, while gas production could be also elevated, causing GWR increasing to 175.8. In Class Ⅲ reservoirs, the reduction of 30% in water production, and increment in GWR from 81.5 to 118.0 can be achieved by placing the well on the top of the hydrate layer, rather than that on the bottom. In addition, the presence of free gas layer, free water layer can promote the pressure-drop interface spread, provide sensible heat, and then accelerate hydrate decomposition further. [Display omitted] • Gas behavior in different reservoirs and horizontal well locations were studied. • Placing bottom-well patterns can increase gas production in Class I reservoir. • Placing middle-well patterns can get higher gas-water ratio in Class II reservoir. • Placing upper-well patterns can get higher gas yield rate in Class III reservoir. • Free air and water layers can promote pressure drop diffusion and provide heat. [ABSTRACT FROM AUTHOR]

In this work, a rapid and sensitive thin‐layer chromatography combined with surface‐enhanced Raman spectroscopy method was established for rapid detection of benzidine and 4‐aminobiphenyl in migration from food contact materials based on Au nanoparticle doped metal‐organic framework. Benzidine and 4‐aminobiphenyl were firstly separated by thin‐layer chromatography to solve the limitation of their overlapping Raman peaks. Then the target molecules were monitored by adding AuNPs/MIL‐101(Cr) on the sample spots. Under the optimum conditions, the concentration of benzidine and 4‐aminobiphenyl can be quantitatively measured in the range of 2.0‐20.0 and1.0‐15.0 μg/L, respectively with good linear relationship, and the limits of detection were 0.21 and 0.23 μg/L, respectively. Furthermore, the developed method was applied to analyze benzidine and 4‐aminobiphenyl in migration of different food contact materials. The recoveries of benzidine and 4‐aminobiphenyl for migration of food contact materials, including paper cups, polypropylene food containers, and polyethylene glycol terephthalate bottles, were 80.6‐116.0 and 80.7‐118% with relative standard deviations of 1.1‐9.1 and 3.1‐9.9%, respectively. Surface‐enhanced Raman scattering detection was performed conveniently in the on‐plate mode without additional elution process. The method shows great potential in rapid monitoring of hazardous substances with overlapping characteristic Raman peaks in food contact materials. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel H 2 S sorbent, fibrous polymeric ionic liquids, was proposed. • The sorbent showed large adsorption capacity and outstanding adsorption kinetics. • An economical water-promoting regeneration method was proposed. • Atom-level study revealed the underlying mechanisms of humidity swing adsorption. • The sorbent presented promising regenerability and cycle stability. Abstract A novel H 2 S adsorbent, fibrous polymeric ionic liquids (PILs), was proposed in this study, for they combine the advantages of ionic liquids and characteristics of macromolecular architecture. After modified with basic anion, the sorbent showed excellent performance for low concentration of H 2 S adsorption under room temperature. The fixed bed breakthrough experiment showed that the adsorption capacity is up to 1.75 mmol/g and the adsorption kinetics is comparable to that of mental oxide at 300 °C. Despite the strong affinity for H 2 S, the saturated sorbent could be regenerated under wet conditions, which inspires an economical water-promoting regeneration method. Further investigations through density functional theory (DFT) calculations revealed that the interface water would alter the reaction pathways of H 2 S adsorption and lower the activation energy of desorption reaction, which makes H 2 S desorption faster. After eight adsorption-desorption cycles, the sorbent did not show any detectable loss of H 2 S adsorption capacity. Therefore, the results of this study indicate that the fibrous PILs are promising regenerable sorbent for low concentration H 2 S removal at room temperature. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • An adsorption model based on realistic diffusion-reaction processes was proposed. • The model consists of three fundamental adsorption steps at different length scales. • The bulk of the sorbent captured CO 2 simultaneously without adsorption front. • Chemical reaction step dominates the whole adsorption process. • This work provides a benchmark to evaluate the simplified adsorption models. Abstract A rigorous dynamic adsorption model, considering the realistic diffusion-reaction processes of CO 2 adsorption onto the amine functionalized mesoporous silica, was proposed in this work. Three fundamental adsorption steps at different length scales were took into account in model development and a numerical algorithm was developed to solve the coupled partial differential equations of the multi-scale model. TGA (Thermal Gravity Analysis) experiments at different temperatures and CO 2 partial pressures were conducted to acquire the dynamic adsorption curves for model fitting and validation. The simulation results based on the proposed model agreed well with the experimental data under all conditions. Through the developed model, the species distribution, mass transfer phenomena and reaction mechanisms at different scales within the sorbent were quantitatively predicted. The results indicated that the bulk of the sorbent captured CO 2 simultaneously, and no adsorption front was observed. After the very early stage, the whole sorbent reacted with CO 2 uniformly. Further mass transfer resistance analysis showed that chemical reaction was the rate-limiting step, and CO 2 diffusion in the amine layer would play an important role in the later stage of adsorption, especially at high temperatures or high CO 2 partial pressures. These findings provided a quantitative insight into dynamic evolution of CO 2 adsorption within the sorbent particle, which would guide the design of sorbents with optimal pore features and amine loadings. [ABSTRACT FROM AUTHOR]

• Numerical simulation of gas production by stepwise depressurization is presented. • The depressurization rate is optimized by genetic algorithm. • The configuration strategies of stepwise depressurization are optimized. • The exploitation efficiency has been improved. Depressurization is one of the most effective methods for hydrate exploitation. Optimization of the pressure-drop strategy for improving the exploitation efficiency requires immediate attention. In this study, a hydrate decomposition model was for the first time combined with a genetic algorithm. The pressure-drop rate and strategy were optimized based on the exploitation efficiency. The depressurization rate of the continuous slow depressurization method was optimized. Subsequently, the best pressure-drop rate for stepwise depressurization was hypothesized and validated. In addition, the stepwise strategy was optimized. For the two depressurization methods, increasing the pressure-drop rate increased the exploitation efficiency, while increasing the number of pressure-drop stages in the stepwise depressurization method adversely impacted the exploitation efficiency. Prolonged constant-pressure intervals reduced the efficiency when there were few pressure-drop stages; however, the opposite trend emerged for a high number of depressurization steps. This study provides guidance for optimizing the production efficiency of hydrate exploitation via depressurization. [ABSTRACT FROM AUTHOR]

Ceramide is one type of sphingolipids, is associated with the occurrence of metabolic diseases, including obesity, diabetes, cardiovascular disease, cancer, and nonalcoholic fatty liver disease. Dihydroceramide, the direct precursors of ceramide, which is converted to ceramide with the dihydroceramide desaturase, is recently regarded as involving in various biological processes and metabolic diseases. The liver and gut ceramide levels are interactional in pathophysiological condition, quantifying hepatic and intestinal ceramide levels become indispensable. The aim of this study is to establish a rapid method for the determination of ceramides including dihydroceramides in liver and small intestinal tissues for researching the mechanisms of ceramide related diseases. The levels of Cer d18:1/2:0, Cer d18:1/6:0, Cer d18:1/12:0, Cer d18:1/14:0, Cer d18:1/16:0, Cer d18:1/17:0, Cer d18:1/18:0, Cer d18:1/20:0, Cer d18:1/22:0, Cer d18:1/24:1, Cer d18:1/24:0, dHCer d18:0/12:0, dHCer d18:0/14:0, dHCer d18:0/16:0, dHCer d18:0/18:0, dHCer d18:0/24:1 and dHCer d18:0/24:0 in mice liver and small intestine were directly quantified by ultra-high performance liquid chromatography-tandem mass spectrometry after methanol extraction. In detail, liver or small intestine tissues were thoroughly homogenized with methanol. The resultant ceramides were separated on a Waters BEH C18 column using gradient elution within 10 min. Positive electrospray ionization with multiple reaction monitoring was applied to detect. In the end, the levels of ceramides in mice liver and small intestine tissues were quantified by this developed method. The limits of detection and quantification of 11 ceramides and 6 dihydroceramides were 0.01–0.5 ng/mL and 0.02–1 ng/mL, respectively, and all detected ceramides had good linearities (R2 > 0.997). The extraction recoveries of ceramides at three levels were within 82.32%–115.24% in the liver and within 83.21%–118.70% in the small intestine. The relative standard deviations of intra- and inter-day precision were all within 15%. The extracting solutions of the liver and small intestine could be stably stored in the autosampler 24 h at 10 °C, the lyophilized liver and small intestine for ceramides quantification could be stably stored at least 1 week at −80 °C. The ceramides and dihydroceramides in normal mice liver and small intestinal tissues analyzed by the developed method indicated that the detected 9 ceramide and 5 dihydroceramides levels were significantly different, in which Cer d18:1/16:0, Cer d18:1/22:0, Cer d18:1/24:1, Cer d18:1/24:0 and dHCer d18:0/24:1 are the main components in the liver, whereas Cer d18:1/16:0 and dHCer d18:0/16:0 accounts for the majority of proportion in the intestinal tissues. A simple and rapid method for the quantification of 11 ceramides and 6 dihydroceramides in the animal tissues was developed and applied. The compositions of ceramides in two tissues suggested that the compositional features should to be considered when exploring the biomarkers or molecular mechanisms. [Display omitted] • Ceramides play important roles on the occurrence of various metabolic diseases. The hepatic and intestinal ceramide levels are correlative dependence and interplay. Accurately quantifying these two tissue ceramide levels become indispensable. • The mixture of chloroform/methanol (2/1) was replaced by methanol solvent, the manipulate steps of liquid-liquid extraction, evaporation and reconstitution commonly used in the published were completely avoided in pretreating sample in the developed method. • Relatively rapid, high specificity and high sensitivity method was developed within 10 min to quantify tissue ceramides based on UPLC-MS/MS. • The compositions of ceramides in two tissues suggested that these unique features should be considered when exploring biomarkers or molecular mechanisms related diseases. [ABSTRACT FROM AUTHOR]

Here, we report a novel AuAg nanoalloy embedded sheet-like β-Bi 2 O 3 (β-Bi 2 O 3 /Au 2 Ag 2) hierarchical microsphere for rapid, sensitive and selective detection of environment pollutants including o -dianisidine (o -diASD) and Hg2+ ions in environmental samples. [Display omitted] • The sheet-like β-Bi 2 O 3 /Au 2 Ag 2 was synthesized by in-situ reduction method. • High SERS activity originates from synergistic effect of AuAg and β-Bi 2 O 3. • Good selectivity, stability and repeatability for SERS analysis. • The practical applications were achieved for analysis of environment pollutants. In this paper, we report a novel surface-enhanced Raman spectroscopy (SERS) substrate based on hierarchical β-Bi 2 O 3 /Au 2 Ag 2 microspheres for rapid, sensitive and selective detection of environment pollutants including o -dianisidine (o -diASD) and Hg2+ in environmental samples. The sheet-like β-Bi 2 O 3 not only provides large specific surface areas for adsorption of molecules and AuAg, but also emerges as semiconductor matrix with chemical enhancement combined with AuAg with electromagnetic enhancement, making promising SERS activity. Particularly, the β-Bi 2 O 3 /Au 2 Ag 2 shows high SERS performance for 4-mercaptobenzoic acid and TMB with minimum detectable concentration of 0.1 μg/L with enhancement factor of 3.1 × 107 and 6.3 × 107, respectively. The density functional theory simulations were further adopted to explain the high SERS activity and selectivity for o -diASD and TMB. Finally, the β-Bi 2 O 3 /Au 2 Ag 2 was applied to direct detection of o -diASD, and indirect detection of Hg2+ by TMB marking in environmental samples. The linearity range of 0.5–200.0 and 0.2–500.0 μg/L with limit of detection of 0.2 and 0.07 μg/L for o -diASD and Hg2+ ions can be achieved, respectively. This method provides a novel strategy in designing and fabricating SERS substrates with high performance for rapid, sensitive and accurate analysis of environmental pollutants. [ABSTRACT FROM AUTHOR]

Herein, Ag nanoparticles decorated MOF-74 (Ni) encapsulated magnetic prickly-like nickel rods (NiRs@MOF-74 (Ni)/Ag) was firstly designed and fabricated for simultaneous surface-enhanced Raman spectroscopy (SERS) analysis of mycotoxins in food samples. The prickly-like NiRs not only provide magnetism with anisotropy structure, but also directly supply Ni2+ for surface initiated encapsulation of MOF-74 (Ni) on NiRs. The as-fabricated NiRs@MOF-74 (Ni)/Ag exhibits good SERS activity due to the enrichment effect of magnetic NiRs, adsorption of MOF-74 (Ni) and localized surface plasmon resonance properties of AgNPs. The enhancement factor for 5,5′-dithiobis-(2-nitrobenzoic acid) and 4-mercaptobenzoic acid can reach 108 level with limits of detection (LOD) of 1.0 ng/L. Subsequently, the magnetic aptamer probes based on NiRs@MOF-74 (Ni)/Ag were fabricated for simultaneous, sensitive and selective SERS analysis of T-2 and deoxynivalenol in food samples. The method exhibited satisfactory linearity in range of 0.5–750.0 μg/L and 0.3–750.0 μg/L with LOD of 0.15 and 0.08 μg/L for T-2 and deoxynivalenol, respectively. The relative errors between the developed method and standard HPLC-MS ranged from −7.7 to 1.4%. Our results open a new venue in design and fabrication of magnetic SERS substrates with unique property for quantification of multiple mycotoxins in complex samples. [Display omitted] • Magnetic SERS substrate based on prickly-like nickel rods (NiRs) developed. • Surface initiated encapsulation of NiRs with MOF-74 (Ni) and AgNPs decoration. • NiRs@MOF-74 (Ni)/Ag exhibits promising magnetism, high SERS activity, good stability and repeatability. • Simultaneous analysis of two mycotoxin using magnetic aptamer probes in food. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-sensitive and selective surface-enhanced Raman spectroscopy (SERS) substrate was designed and fabricated for rapid determination of 4,4′-methylenedianiline (4,4′-MDA) based on flower-like gold-silver nanoalloys embedded nickel-cobalt layered double hydroxide composites (NiCo/Au 2 Ag 1). Flower-like NiCo-LDH with thin nanosheets were prepared via the hydrothermal method and the gold-silver nanoalloys were in-situ embedded on the surface of NiCo-LDH. The ultrahigh SERS activity of NiCo/Au 2 Ag 1 was originated from the synergistic effect of electromagnetic and chemical mechanism induced by AuAg nanoalloys and NiCo-LDH, respectively. In addition, the flower-like of NiCo-LDH can provide more sites for AuAg and target molecules loading, further making highly sensitive SERS activity. The minimum detectable concentration for 4-mercaptobenzoic acid (4-MBA), crystal violet (CV) and Rhodamine 6 G (R6G) are 1.0 pg L−1 and 1.0 ng L−1 with enhancement factor (EF) of 1.2 × 1010, 1.7 × 108 and 1.1 × 108, respectively. The theoretical simulations and experiment results can further confirm the high SERS performance of NiCo/Au 2 Ag 1 and superiority of NiCo-LDH compared to Ni(OH) 2 and Co(OH) 2. Good selectivity and anti-interference for 4,4′-MDA indicates great potentials in contaminants screening and detection. Subsequently, the NiCo/Au 2 Ag 1 composites were used to determine group 2B carcinogen of 4,4′-MDA in water samples and indoor dust. The fabricated NiCo/Au 2 Ag 1 substrate show good satisfied linearity (5.0–750.0 μg L−1) with low limits of detection (LOD) of 1.5 μg L−1, and the practical applications in environmental samples were obtained with good rapidity and accuracy. The developed NiCo/Au 2 Ag 1 offers a novel strategy for fabricating SERS substrates with high sensitivity and selectivity in rapid monitoring of environmental pollutants. Herein, we introduced flower-like gold-silver nanoalloys embedded nickel-cobalt layered double hydroxide composites (NiCo/Au 2 Ag 1) for determination of 4,4′-methylenedianiline (4,4′-MDA) in environmental water samples and indoor dust by surface-enhanced Raman spectroscopy (SERS) with high sensitivity and selectivity. [Display omitted] • The flower-like NiCo/Au 2 Ag 1 composites were synthesized by in-situ reduction method. • The EF for 4-MBA, CV and R6G are 1.2 × 1010, 1.7 × 108 and 1.1 × 108. • The sensitivity and selectivity were investigated by DFT simulations. • The practical applications were achieved for 4,4′-MDA detection in environmental samples. [ABSTRACT FROM AUTHOR]

Carcinogens in food samples show great potential threat to human health due to their wide distribution and high carcinogenicity. In this work, branched AuCu nanoalloy doped mesoporous graphitic carbon nitride hybrid membrane (mpg-C 3 N 4 /AuCu) was fabricated for SERS analysis of carcinogens including benzidine and zearalenone in food. The AuCu was in-situ grown on mpg-C 3 N 4 to form mpg-C 3 N 4 /AuCu composites. The as-fabricated mpg-C 3 N 4 /AuCu membrane can effectively combined synergistic effect of localized surface plasmon resonance properties of branched AuCu nanoalloy and semiconductor characteristics of mpg-C 3 N 4. The limit of detection for crystal violet is 1.0 ng/L with enhancement factor of 3.7 × 108. The mechanism of high SERS activity of mpg-C 3 N 4 /AuCu membrane was investigated by density functional theory simulations. The mpg-C 3 N 4 /AuCu membrane was used for direct determination of benzidine, and indirect determination of zearalenone with 3,3′,5,5′-tetramethylbenzidine as markers in food. The limits of detection of SERS method were 0.14 and 0.03 μg/L for benzidine and zearalenone, respectively. It provides a new strategy for design and fabrication of high-quality SERS substrates for carcinogens analysis. [Display omitted] • The branched hydrophobic AuCu nanoalloy was in-situ grown on mpg-C 3 N 4. • High SERS activity originates from synergistic effect of branched, hydrophobic AuCu and mpg-C 3 N 4. • Good selectivity, stability and repeatability for SERS analysis. • The practical applications were achieved for carcinogens analysis. [ABSTRACT FROM AUTHOR]

Ten novel palladium(II) complexes with dipyrido[3,2- d :2′,3′- f ]quinoxaline (Dpq)/dipyrido[3,2- a :2′,3′- c ](6,7,8,9-tetrahydro)phenazine (Dpqc) and 4-toluensulfonyl- L -amino acid dianion, [Pd(Dpq)(TsvalNO)]·H 2 O ( 1a ), [Pd(Dpq)(TsileNO)]·H 2 O ( 1b ), [Pd(Dpq)(TsserNO)] ( 1c ), [Pd(Dpq)(TsthrNO)]·1.5H 2 O ( 1d ), [Pd(Dpq)(TsleuNO)]·0.5H 2 O ( 1e ), [Pd(Dpq)(TspheNO)] ( 1f ), [Pd(Dpqc)(TsvalNO)] ( 2a ), [Pd(Dpqc)(TsileNO)] ( 2b ), [Pd(Dpqc)(TsserNO)]·H 2 O ( 2c ) and [Pd(Dpqc)(TsthrNO)]·0.5H 2 O ( 2d ) have been synthesized and characterized by elemental analysis, IR, UV, 1 H NMR and mass spectrometry techniques. Crystal structure of the complex 1f has been determined by X-ray diffraction. The cytotoxicity was tested by MTT assay. The results indicated that the complexes 1a and 2a showed better cytotoxicity than cisplatin against MCF-7. The complex 1e had higher cytotoxicity than cisplatin against K562. Both the N donating ligands and the amino acid have important effects on the cytotoxicity. [ABSTRACT FROM AUTHOR]

With its special physical and chemical properties, terbium has been widely used, which has inevitably increased the chance of human exposure to terbium-based compounds. It was reported that terbium mainly deposited in bone after introduction into the human body. Although some studies revealed the effects of terbium on bone cell lines, there have been few reports about the potential effect of terbium on adhesion and differentiation of mesenchymal stem cells (MSCs). In this study, we investigated the effects of terbium on the adhesion and osteogenic and adipogenic differentiation of MSCs and the associated molecular mechanisms. Our data reveal that terbium promoted the osteogenic differentiation in a time-dependent manner and conversely inhibited the adipogenic differentiation of MSCs. Meanwhile, the cell-cell or cell-matrix interaction was enhanced by activating adherent-related key factors, which were evaluated by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Real-time RT-PCR and Western blot analysis were also performed to further detect osteogenic and adipogenic biomarkers of MSCs. The regulation of terbium on differentiation of MSCs led to the interaction between the transforming growth factor β/bone morphogenetic protein and peroxisome-proliferator-activated receptor γ (PPARγ) signaling pathways, resulting in upregulation of the osteogenic master transcription factors, such as Runt-related transcription factor 2, bone morphogenetic protein 2, collagen I, alkaline phosphatase, and osteocalcin, and downregulation of the adipogenic master transcription factors, such as PPARγ. The results provide novel evidence to elucidate the mechanisms of bone metabolism by terbium and may be helpful for more rational application of terbium-based compounds in the future. Graphical abstract: The effects of terbium on the osteogenic and adipogenic differentiation of mesenchymal stem cells (MSCs) and the associated molecular mechanisms were investigated. The results suggest that terbium promotes the osteogenic differentiation of MSCs via the transforming growth factor β ( TGFβ)/bone morphogenetic protein ( BMP) signaling pathway. ALP alkaline phosphatase, BSP bone sialoprotein, C/EBP CCAAT/enhancer binding protein, Col I collagen I, ERα estrogen receptor α, GDF growth differentiation factor, OCN osteocalcin, PPARγ peroxisome-proliferator-activated receptor γ, Runx2 Runt-related transcription factor 2[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Here, we report a hexagonal boron nitride/AuAg nanoalloys hybrids membrane (h-BN/AuAg) as solid surface-enhanced Raman spectroscopy (SERS) substrate for sensitive SERS detection. The AuAg nanoalloys were in-situ grown on h-BN by chemical reduction method. Then the h-BN/AuAg membrane was fabricated by simple filtration of h-BN/AuAg nanoalloys hybrids (h-BN/AuAg NAHs). The possible enhancement mechanism including electromagnetic mechanisms (EM) and chemical mechanisms (CM) were illustrated by finite-difference time-domain (FDTD) and density functional theory (DFT) simulation in detail. The proposed SERS method demonstrated high sensitivity, satisfied selectivity, good repeatability and reproducibility for the SERS detection of melamine in liquid milk samples. [Display omitted] • 1. The membrane-based SERS substrate was prepared by simple filtration procedure. • 2. The optimized SERS activity can be obtained by tuning with Au/Ag ratio. • 3. The h-BN/Au 1 Ag 3 provide analytical enhancement factor at 3.6 × 108 level. • 4. Good relationship between SERS intensity and melamine concentrations was obtained. In this work, a hexagonal boron nitride (h-BN)/AuAg nanoalloy hybrids (NAHs) was synthesized to fabricate h-BN/Au 1 Ag 3 membrane as a solid surface-enhanced Raman spectroscopy (SERS) substrate for sensitive SERS detection of melamine. The AuAg nanoalloys were in situ grown on h-BN by chemical reduction method, and the Au/Ag molar ratio was tuned to achieve optimal SERS performance. After the SERS performance of h-BN/AuAg NAHs with different Au/Ag ratios was analyzed, h-BN/Au 1 Ag 3 NAHs were chosen for SERS analysis. The h-BN/Au 1 Ag 3 membrane can be obtained through simple filtration of h-BN/Au 1 Ag 3 NAHs on chromatographic paper. As expected, the solid SERS substrates of h-BN/Au 1 Ag 3 membrane were uniform and demonstrated good selectivity, repeatability and reproducibility for SERS detection of melamine. The results demonstrate that h-BN/Au 1 Ag 3 membrane exhibited high SERS activity for 4-mercaptobenzoic acid (4-MBA) with limit of detection (LOD) at 1.0 ng L−1, and its analytical enhancement factor (AEF) reached 3.6 × 108. The possible enhancement mechanism, including electromagnetic mechanisms (EM) and chemical mechanisms (CM) were illustrated by finite-difference time-domain (FDTD) and density functional theory (DFT) simulations in detail, respectively. The concentration of melamine in the 0.05–5.0 mg L−1 range showed good linear relationship (R2 = 0.9940) with SERS intensity with LOD of 0.01 mg L−1. Finally, the recoveries of melamine in liquid milk samples are 87.7–105.7% with relative standard deviations (RSDs) in range of 0.6–2.6%, providing precise safety evaluation of melamine in milk samples. [ABSTRACT FROM AUTHOR]

The analysis of contaminants in migration of food contact material (FCMs) is an urgent demand for food safety. In this study, melamine and formaldehyde in melamine kitchenware were selectively analyzed by surface-enhanced Raman scattering (SERS) via aptamer/derivatization-based membrane assembly. The membrane assembly was designed by simple filtration of Ag nanoparticles-decorated "stellate" silicon dioxide (SiO 2 /Ag) and composites of reduced graphene oxide and Ag nanoparticles (rGO/Ag) functioned with specific reagents. High selectivity can be realized by melamine aptamer and derivatization reagent of formaldehyde, respectively. The relative standard deviations (RSDs) of melamine and formaldehyde analysis for 11 replicate measurements, 14 consecutive days and 25 batches are less than 6.0 %, which shows excellent repeatability and reproducibility. After the method was validated, the limits of detection (LOD) for melamine and formaldehyde are 0.15 mg/L and 0.21 mg/L, respectively. The developed method was applied to determine the content of melamine and formaldehyde in migration of melamine kitchenware with low relative errors (less than 5.3 %) compared to chromatographic results. The recoveries of melamine and formaldehyde for migrations of melamine kitchenware are 91.2–110.0 % and 94.0–106.0 % with RSDs in range of 1.8–8.3 % and 4.7–9.1 %, respectively. The method proposed a new concept of convenient, portable and reliable strategy for analysis of melamine and formaldehyde in migration from FCMs. Here, we introduced an aptamer/derivatization-based membrane assembly by simple filtration and incubation procedure for selective analysis of melamine and formaldehyde in migration of melamine kitchenware by surface-enhanced Raman scattering. [Display omitted] • A high-throughput membrane assembly was designed and fabricated for SERS detection. • The membrane endows selective and sensitive detection of melamine and formaldehyde. • The method provides a new strategy for detection of multiple contaminants from FCMs. [ABSTRACT FROM AUTHOR]

Tunable whispering-gallery-mode (WGM) lasers have been paid lots of attention for their potential applications in the photonic field. Here, a tunable polymer WGM laser based on laser diode pumping is realized with a threshold of 0.43 MW/cm2 per pulse. The WGM laser is realized by a microfluidic microcavity, which consists of a quartz capillary and gain materials. The laser performance keeps stable for a long time (3.5 h), pumped by a 50-ns 50 Hz laser diode with a pumping peak power density of 1.08 MW/cm2 per pulse. The lasing wavelength can be tuned over 15 nm by changing the gain material concentration from 3.5 mg/mL to 12.5 mg/mL in the microfluidic channel. Moreover, the lasing mode can be switched between transverse magnetic (TM) and transverse electric (TE) modes by adjusting the pump polarization. These results provide the basis for designing nanophotonic devices with laser diode pumping. [ABSTRACT FROM AUTHOR]

Recently, wearable sensor technology has drawn attention to many health-related appliances due to its varied existing optical, electrical, and mechanical applications. Similarly, we have designed a simple and cheap lift-off fabrication technique for the realization of large-area biocompatible random lasers to customize wearable sensors. A large-area random microcavity comprises a matrix element polymethyl methacrylate (PMMA) in which rhodamine B (RhB, which acts as a gain medium) and gold nanorods (Au NRs, which offer plasmonic feedback) are incorporated via a spin-coating technique. In regards to the respective random lasing device residing on a heterogenous film (area > 100 cm2), upon optical excitation, coherent random lasing with a narrow linewidth (~0.4 nm) at a low threshold (~23 μJ/cm2 per pulse) was successfully attained. Here, we maneuvered the mechanical flexibility of the device to modify the spacing between the feedback agents (Au NRs), which tuned the average wavelength from 612.6 to 624 nm under bending while being a recoverable process. Moreover, the flexible film can potentially be used on human skin such as the finger to serve as a motion and relative-humidity sensor. This work demonstrates a designable and simple method to fabricate a large-area biocompatible random laser for wearable sensing. [ABSTRACT FROM AUTHOR]

In this work, we introduced an aptamer modified Au nanoparticles doped covalent organic frameworks composite (IBAs-AuNPs/COF) to improve the property of selective enrichment of insulin from serum samples. The Au nanoparticles were immobilized on imine-based COF by in-situ reduction reaction via mussel inspired polydopamine coating, and then sulfhydryl-containing aptamers were bonded to the surface of AuNPs through an Au-S linkage. Due to the excellent adsorption property of COF and specific recognition between insulin and IBAs, the IBAs-AuNPs/COF composites show selective and satisfactory extraction property to insulin in serum samples. Excellent specifity was obtained for insulin in the presence of 50-fold interfering substances including human immunoglobulin, lysozyme and biotin. The concentrations of insulin in the range of 1.0 to 50.0 μg L−1 show good linear relationship (R2 = 0.9917) with limit of detection and limit of quantitation of 0.28 μg L−1 and 0.93 μg L−1, respectively. Then, the IBAs-AuNPs/COF composites were applied to enrich insulin in serum samples followed by analysis with matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). After the recovery experiment, the developed method shows good recoveries in range of 91.6%–112.4% with low RSD value (2.4%–9.4%, n = 3) for diabetic and healthy serum samples. The developed IBAs-AuNPs/COF composites propose a new perspective for selective and efficient enrichment of biomarkers in serum samples by functionalized COF. [ABSTRACT FROM AUTHOR]

Permeability in hydrate-bearing sediment critically governs fluid flow and determines hydrate nucleation, growth, and distribution, making it important to characterize the evolution of permeability with respect to water and gas during hydrate formation. This study uses CT scanning of krypton hydrate formation in silica sand using the excess gas method, together with a pore network model, to investigate variations in hydrate morphology and associated permeation. The results show that during hydrate formation, the growth habit mainly varies from grain-coating to patchy with an increase in hydrate saturation; however, at relatively low saturation, hydrate preferentially grows as a grain-cementing habit. Theoretical models of a capillary tube and of a Kozeny grain both predict that permeability in grain-coating hydrates will be higher than in patchy hydrates. We thus recognise a correlation of permeability and hydrate saturation for multiple growth habits that is of interest for gas production from hydrate reservoirs. Under lower water saturation, there is a decrease in relative permeability to water but an increase in relative permeability to gas, due to the reduction in pore shape factors. Conversely, an upward shift in relative permeability to water and a downward shift in relative permeability to gas is found with hydrate formation under higher water saturation, owing to the Jamin effect. Steeper curves of relative permeability to gas and water with increasing hydrate saturation resulted in a reduction of the co-cementation zone for water and gas, even if or though no gas migrates. The results suggest that, due to the low relative permeability of gas, higher water saturation sediments result in an excess water yield accompanied by low gas production that is not desirable for natural gas hydrate production. Therefore, improving the permeability and weakening the Jamin effect are critical for gas production in marine hydrate reservoirs, especially in low permeability sediments. • CT scanning of Kr hydrate growth is used as input to modeling of multi-phase flow properties in hydrate bearing sediments • Hydrate pore habit shifts from coating to cementing as hydrate saturation increases. • Under lower S w , hydrate formation inhibits water flow due to reduced shape factor. • Under higher S w , hydrate growth impedes gas migration in fine pores due to the Jamin effect. [ABSTRACT FROM AUTHOR]

Near infrared (NIR)-emitting persistent luminescent nanoparticles (PLNPs) have advantages such as long afterglow, high photostability and deep tissue spectral penetration. A NIR-emitting inner filter effect (IFE) probe for arsenic(III) is described here. It is composed of polyethyleneimine-coated PLNPs and gold nanorods (AuNPs) coated with dithiothreitol. The probe can detect arsenic(III) (= arsenite) selectively even in the presence of interfering substances. The PLNPs and AuNPs were prepared by a hydrothermal method combined with high-temperature calcination and seed-mediated growth mechanism, respectively. The PLNPs show excellent NIR luminescence (with excitation/emission peaks at 254/695 nm) and long afterglow (lifetime >1200 s). The use of polyethyleneimine improves water solubility and provides positive surface charges for the PLNPs. On exposure to arsenite ions, the luminescence of the probe at 695 nm is restored. Under the optimum conditions, the method can detect As(III) in the 0.067 to 13.4 μmol·L−1 concentration range with good linear relationship (R2 = 0.99734), and the detection limit (at S/N = 3) is 55 nmol·L−1. The precision of this method was demonstrated by 11 replicate detections of 2 μmol·L−1 As(III), and the relative standard deviations (RSD) is 2.1%. The practicality was evaluated by the analyses of real water samples and recoveries for the water samples spiked with 2, 5 and 10 μmol·L−1 of As(III) were 89.8%-100.1% with RSDs ranging from 3.0-5.7%.A near infrared-emitting inner filter effect (IFE) inhibition probe is presented. It is based on the combination of polyethyleneimine (PEI)-coated NIR-emitting persistent luminescent nanoparticles (type Zn1.25Ga1.5Ge0.25O4: Cr3+, ZGGO) (PLNPs-PEI) with dithiothreitol (DTT)-coated gold nanorods (AuNPs) (DTT-AuNPs) to detect arsenite. [ABSTRACT FROM AUTHOR]

A colorimetric probe for determination of As(III) ions in aqueous solutions on basis of localized surface plasmon resonance (LSPR) was synthesized. The dithiothreitol molecules with two end thiols covalently combined with Au Nanorods (AuNRs) with an aspect ratio of 2.9 by Au-S bond to form dithiothreitol coated Au Nanorods (DTT-AuNRs), acting as colorimetric probe for the determination of As(III) ions. With the adding of As(III) ions, the AuNRs will be aggregated and leading the longitudinal SPR absorption band of DTT-AuNRs decrease due to the As(III) ions can bind with three DTT molecules through an As-S linkage. The potential factors affect the response of DTT-AuNRs to As(III) ions including the concentration of DTT, pH values of DTT-AuNRs, reaction time and NaCl concentration were optimized. Under optimum assay conditions, the DTT-AuNRs colorimetric probe has high sensitivity towards As(III) ions with low detection limit of 38 nM by rules of 3σ/k and excellent linear range of 0.13–10.01 μM. The developed colorimetric probe shows high selectivity for As(III) ions sensing and has applied to determine of As(III) in environmental water samples with quantitative spike-recoveries range from 95.2% to 100.4% with low relative standard deviation of less than 4.4% (n = 3). [ABSTRACT FROM AUTHOR]

The blender of active material R6G and film forming agent PDMS are spincoated onto a sandpaper substrate to fabricate the random laser of thin layer. The sandpaper provides support for the random laser and the sand particles on the sandpaper substrate provide the scattering mechanism of random lasing output. The random lasing emission centres at 560 nm, with a threshold of about 13 mJ/cm2. This design provides a new and cheap method to fabricate random lasers. [ABSTRACT FROM AUTHOR]

The accumulation of ice on wind turbine blades is a serious threat to the safety of wind power generation. Anti-icing techniques with low energy consumption, especially when combined with superhydrophobic surfaces, have recently attracted increasing levels of interest. In this work, the anti-icing mechanism of superhydrophobic surfaces was investigated by conducting the two-dimensional numerical analysis of the flow patterns of liquid water on surfaces with different wettability, which was based on the phase field method (PFM) and a dynamic contact angle (DCA) model. It is found that the wettability of surfaces significantly influences the flow, break, and shedding behaviors of liquid water on the surfaces. An increase in contact angle (CA) leads to more frequent break and shedding behaviors, and the flow pattern of liquid water gradually transformed from continuous water film to fragmented droplets because of the vortical flow field. In addition, it is also investigated that when the CA of surfaces exceeded 145°, the broken liquid water completely shed away in 0–0.1 chord length. Moreover, the average chordwise location (x ‾ /c) and maximum chordwise location (x max /c) of the liquid water that had traveled the farthest on the surface in 30 ms gradually decreased with increasing contact angle, which is beneficial to superhydrophobic-dry anti-icing. What's important, the wettability characteristics should be responsible for the unique water flow patterns coupled with shear stress, which has been validated again, and previously proposed by our work. The results of this study provide theoretical support for the incorporation of superhydrophobic surfaces in anti-icing technology applied to wind turbine blades, which is promising for solving the icing issue of wind turbine blades with low energy consumption. [ABSTRACT FROM AUTHOR]

An available dressing material which promotes skin tissue repair is of significant importance for public health. Moreover, dynamic wounds have special requirements for hydrogel dressings due to their motion state. Correspondingly, a double crosslinked hydrogel was prepared based on amide and coordination bonds from carboxylated polyvinyl alcohol (PC) and chitosan (CS)/Fe3+. The hydrogel exhibited excellent swelling ratio and suitable biodegradability, which is beneficial to the tissue repair. The results showed that hydrogels with crosslinked structure possessed better unique properties, such as stronger mechanical (78 kPa of G') and adhesion properties, and shorter self-healing time (5 mins), the change of which was consistent with dynamic wounds. The hydrogel exhibited not only antibacterial activity (98 % fatality rate), but also superior hemostatic capacity during the wound healing process. In addition, the hydrogel could shorten skin healing time to 14 days, and obviously accelerated skin structure reconstruction by promoting angiogenesis and collagen deposition. Therefore, double crosslinked hydrogel is a promising dynamic wound dressing. • The structure of multifunctional hydrogel is physicochemical double crosslinked. • The hydrogel with stable internal structure and mechanical property • The hydrogel can stably adhere to wet tissue surfaces on moving. • The hydrogel possesses excellent self-healing and inhibit bacterial activities. • The hydrogel can effectively induce angiogenesis and skin wound healing in vivo. [ABSTRACT FROM AUTHOR]

The coassembly of primary particles into heterostructures represents a significant strategy for advanced fabrication of multi‐functional materials or devices, and templated assembly has shown remarkable advantage for deterministic placement of particles and the efficient integration with substrates. However, template induced particles coassembly, which is significant for integrating multicomponents at desired positions, is still challenging. Herein, a facile strategy of embossed templateinduced particles coassembly for diverse superstructures and precise patterns is reported. Tunable region selective assembly of particles is demonstrated by controlling the resistance force via designing the embossed edge and surface roughness of the template. Through regulating the template morphologies and particles composition, well‐controlled coassembly of "flower" shaped heterostructure and chiral superstructure arrays are realized. Furthermore, the printable nanomaterials self‐assembly template is employed to achieve totally bottom‐up fabrication of excitation responsive heterostructure arrays, in which the multi‐photons process based energy transfer is studied to show the application in high‐secure encryption. With the advantage of accurate position and compatible to different materials, this strategy is expected to provide a promising platform for fabricating micro/nanoscale advanced devices. [ABSTRACT FROM AUTHOR]

Amine blends have been extensively studied as advanced solvents modification for CO 2 absorption. Due to the lack of knowledge on mechanism of amines interaction, reaction in blends was traditionally regarded as parallel reactions between CO 2 and different amines. In this work, the kinetics of CO 2 reaction with blends of two promising diamines, piperazine (PZ), N-(2-aminoethyl) ethanolamine (AEEA), were studied in a wetted wall column. The reaction rate constants of single amine were derived from kinetic data based on the zwitterion and termolecular mechanism for PZ and AEEA, respectively. It is interesting to find that the overall reaction rate of the blend is 12.0–28.1% lower than the calculated value through parallel reaction mechanism, which indicates the strong interaction between PZ and AEEA. A ‘zwitterion bridge’ reaction pathway was proposed as the microscopic mechanism of the interaction in the blend. Based on the kinetic models and experimental data, the interaction that PZ can promote the reaction in amines blend by transferring CO 2 to AEEA through the PZ-CO 2 intermediate was revealed. Besides, the interaction was proved to be a fast reaction with the reaction rate of same magnitude compared with the zwitterion hydrolysis reaction. The mechanisms of interaction between the two amines are further investigated through density functional theory (DFT). Results of simulation, in terms of activation energy and molecular geometry deformation, indicate that the PZ prefers a direct reaction with CO 2 rather than the reaction with the AEEA-CO 2 intermediate. [ABSTRACT FROM AUTHOR]

• A method has been developed to quantify the levels of salivary amino acids which may indicate dysfunction of the body. • Salivary amino acid profile is quantified by a single quadrupole mass detector (QDa), which is very simple and easy to operate in routine laboratory. • The developed method is rapid which only takes 6min to complete a single run after 10min derivatization. • The method has potential value in the clinical translational application. Abnormal salivary amino acid (AA) levels may indicate dysfunction of the body. Being noninvasive, sampling easily and cost-effective of saliva, a rapid, precise and simple analysis method has become very important for quantitative salivary AA profiles. After one-step to precipitate protein, the resultant extraction was derived with 6-aminoquinolyl- N -hydroxysuccinimidyl carbamate (AQC) within 10 min. Quantitation of AA profile was achieved within 6 min in a single run by ultra-high performance liquid chromatography coupled with a single quadrupole mass spectrometry (UHPLC-QDA detector). The method was validated with acceptable accuracy ranging from 80.33 % to 122.31 %, appropriate linearity with the coefficient (R2) more than 0.991, good intra- and inter-day precision, repeatability and stability (RSD < 15 %). The recoveries at three different spiked concentrations ranged over 79.18 %–125.36 % while the matrix effect was from −19.86 % to 11.95 %. This simple, rapid and robust method was successfully applied to quantify human salivary 30 amino acids, in which the levels of taurine, γ-aminobutyric acid, methionine and tryptophan in healthy people were close to the LOQs. Besides, the levels of histidine and cystine were not able to be measured due to their relatively high LOQs, which were considered as the limitations of this developed method. [ABSTRACT FROM AUTHOR]

The 6th International Workshop on Heat/Mass Transfer Advances for Energy Conservation and Pollution Control (IWHT2021) was successfully held online from August 13 to 16, 2021, in Harbin, China. The workshop aimed to provide a global platform for the exchange of cutting-edge technological knowledge and research on heat and mass transfer issues related to energy conservation and pollution management. The event featured plenary lectures, keynote lectures, oral presentations, and posters covering various topics such as nuclear energy, advanced energy systems, heat exchangers, and heat/mass transfer enhancement techniques. Nine research papers from the workshop were selected for inclusion in a special issue of Heat Transfer Engineering. The 7th IWHT conference is scheduled to take place in Tokushima, Japan in 2023. [Extracted from the article]

We demonstrate a microfluidic flowmeter based on a polymer whispering gallery mode (WGM) resonant microcavity. The microcavity is fabricated by coating the dye-doped polymer on the capillary tube. The flowmeter measures the flow velocity based on the temperature variation by the thermo-optic effect. The refractive index of the microcavity changes when the temperature decreases, which is caused by air flow cooling down the microcavity. Therefore, the flow of the fluid can be estimated through calculating the wavelength shift of the resonant microcavity. We achieve a sensitivity of 17 p.m./sccm, and the dynamic range up to 50 sccm. This work will provide a platform for microfluidic flowmeter and miniaturized lasers sensing. The flowmeter measures the flow velocity based on the temperature variation by the thermo-optic effect. The refractive index of the microcavity changes when the temperature decreases, which is caused by air flow cooling down the microcavity. Therefore, the flow of the fluid can be estimated through calculating the wavelength shift of the resonant microcavity. [Display omitted] • The flowmeter measures the flow velocity based on the thermo-optic effect. • The changes of fluid flow can be read out optically using a microfluidic flowmeter through calculating the wavelength shift in the resonant microcavity. [ABSTRACT FROM AUTHOR]

Matrix interference resulting from the nonspecific adsorption of non-target components, particularly proteins (fouling), onto sensor surfaces poses a persistent challenge in electrochemical detection of food hazards. The development of antifouling sensor surfaces presents a viable approach to mitigate nonspecific adsorption. In this study, a novel antifouling electrochemical aptasensor, utilizing a zwitterionic polymer, was developed for the sensitive, accurate, and selective detection of tetracycline (TC) in milk. This sensor employs a poly (dopamine)-poly (sulfobetaine methacrylate) (PDA-PSBMA) antifouling copolymer, which is synthesized through an in-situ initiated copolymerization of dopamine on the sensor's surface. Subsequently, the thiol-containing aptamers were immobilized onto the PDA-PSBMA coating through a Michael addition reaction with the poly(dopamine). The resulting antifouling electrochemical aptasensor exhibited robust antifouling performance in various single protein solutions and diluted milk samples, coupled with sensitive and selective recognition of TC. The sensor demonstrated a broad linear response range of 0.1–1000.0 ng mL−1 and a low limit of detection (LOD) of 68.0 pg mL−1. The antifouling electrochemical aptasensor proved effective in assaying TC in diluted milk, with recoveries ranging from 100.0 % to 104.4 %, eliminating the need for additional pretreatments due to its exceptional resistance to nonspecific adhesion. [Display omitted] • DA self-polymerization initiated free radical polymerization of SBMA. • One-step prepared PDA-PSBMA copolymer showed excellent antifouling ability. • Thiol-containing aptamer was introduced by a Michael addition reaction with the PDA. • An antifouling electrochemical aptasensor based on PDA-PSBMA was proposed. • Sensitive TC analysis in diluted milk can be realized without other pretreatments. [ABSTRACT FROM AUTHOR]

The tilt-depth method can be used to make fast estimation of the top depth of magnetic bodies. However, it is unable to estimate bottom depths and its every inversion point only has a single solution. In order to resolve such weaknesses, this paper presents an improved tilt-depth method based on the magnetic anomaly expression of vertical contact with a finite depth extent, which can simultaneously estimate top and bottom depths of magnetic bodies. In addition, multiple characteristic points are selected on the tilt angle map for joint computation to improve reliability of inversion solutions. Two- and threedimensional model tests show that this improved tilt-depth method is effective in inverting buried depths of top and bottom bodies, and has a higher inversion precision for top depths than the conventional method. The improved method is then used to process aeromagnetic data over the Changling Fault Depression in the Songliao Basin, and inversion results of top depths are found to be more accurate for actual top depths of volcanic rocks in two nearby drilled wells than those using the conventional tilt-depth method. [ABSTRACT FROM AUTHOR]

Microlasers hold great promise for the development of photonics and optoelectronics. At present, tunable microcavity lasers, especially regarding in situ dynamic tuning, are still the focus of research. In this study, we combined a 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) piezoelectric crystal with a Poly [9,9-dioctylfluorenyl-2,7-diyl] (PFO) microring cavity to realize a high-quality, electrically tunable, whispering-gallery-mode (WGM) laser. The dependence of the laser properties on the diameter of the microrings, including the laser spectrum and quality (Q) value, was investigated. It was found that with an increase in microring diameter, the laser emission redshifted, and the Q value increased. In addition, the device effectively achieved a blueshift under an applied electric field, and the wavelength tuning range was 0.71 nm. This work provides a method for in situ dynamic spectral modulation of microcavity lasers, and is expected to provide inspiration for the application of integrated photonics technology. [ABSTRACT FROM AUTHOR]

Ultra-small carbon dots can promote anticancer efficiency by enhancing tumor penetration in breast cancer under near-infrared-II irradiation. [Display omitted] Because of the particular environment of the tumor microenvironment, improving the deep penetration of drugs in tumor sites is a critical problem to improve the therapeutic effect of the tumor. The ultra-small nanoparticles can achieve deep tumor tissue penetration without modification, which shows tremendous significance in tumor therapy. In this work, the ultra-small permeable carbon dots (PCD) have been developed with near-infrared-II (NIR-II) window photothermal irradiation and good biocompatibility. These PCD showed multi-color fluorescence under visible light and photoacoustic signals under an excitation of 808 nm, guiding fluorescence and photoacoustic imaging for location and distribution in vitro and vivo. The PCD could penetrate the deep tissue in tumor spheroids and tissues. Meanwhile, the irradiated depth of the NIR-II window can provide sufficient photothermal energy with the deep penetration of PCD in tumor tissue to cause tumor ablation. Therefore, this PCD can be used as a safe, fluorescent, and photoacoustic imaging agent for guided NIR-II photothermal tumor therapy, which provides a new direction for the use of ultra-small carbon dots in anticancer therapy in the future. [ABSTRACT FROM AUTHOR]

Bile reflux gastritis (BRG) is associated with the development of gastric cancer (GC), but the specific mechanism remains elusive. Here, a comprehensive study is conducted to explore the roles of refluxed bile acids (BAs) and microbiome in gastric carcinogenesis. The results show that conjugated BAs, interleukin 6 (IL‐6), lipopolysaccharide (LPS), and the relative abundance of LPS‐producing bacteria are increased significantly in the gastric juice of both BRG and GC patients. A secondary BA, taurodeoxycholic acid (TDCA), is significantly and positively correlated with the LPS‐producing bacteria in the gastric juice of these patients. TDCA promotes the proliferation of normal gastric epithelial cells (GES‐1) through activation of the IL‐6/JAK1/STAT3 pathway. These results are further verified in two mouse models, one by gavage of TDCA, LPS, and LPS‐producing bacteria (Prevotella melaninogenica), respectively, and the other by bile reflux (BR) surgery, mimicking clinical bile refluxing. Moreover, the bile reflux induced gastric precancerous lesions observed in the post BR surgery mice can be prevented by treatment with cryptotanshinone, a plant‐derived STAT3 inhibitor. These results reveal an important underlying mechanism by which bile reflux promotes gastric carcinogenesis and provide an alternative strategy for the prevention of GC associated with BRG. [ABSTRACT FROM AUTHOR]

• This review systematically summarizes the up-to-date advances of Ru based catalysts from typical structures, main synthesis methods and hydrogenation applications of NEC. • The NEC hydrogen storage mechanism of Ru-based catalysts, and relationship between structures and catalytic performance are deeply discussed. • This review paves the way for future research and applications of Ru-based catalysts for hydrogen storage. N-ethylcarbazole (NEC) hydrogen storage is a very effective strategy to realize large-scale safe storage of hydrogen. Therefore, the development of high-efficiency catalysts is crucial to promote NEC hydrogen uptake reaction. Among numerous catalysts, precious metal ruthenium (Ru) has been demonstrated to be a promising catalyst for NEC hydrogenation reduction because of its excellent catalytic activity and good stability. Therefore, this review first summarizes typical structures and synthesis methods of Ru-based catalysts. Then, their latest progress and the catalytic mechanism in NEC hydrogenation is discussed in detail. At last, a few optimistic outlooks and potential challenges are highlighted to guide future research and practical applications of Ru-based catalysts in catalytic NEC hydrogenation. [ABSTRACT FROM AUTHOR]

With the wide use of rare earth nanomaterials in industry, environmental control, and medicine with their unique properties, it has focused on the exposure of humans to the rare earth nanoparticles in recent years. Because of the similar properties of rare earth and calcium, rare earth nanoparticles can deposit in the bone and affect the osteogenic differentiation of bone mesenchymal stem cells (BMSCs). La(OH)3 nanoparticles are widely used in the catalysis, sensor, electrode, and luminescent materials. However, there are few reports about the bioactivity of La(OH)3 nanoparticles on the bone metabolism. In this work, three La(OH)3 nanorods have been got by hydrothermal method, Long-, Medium-, and Short-La(OH)3 nanorods, the lengths of which were of ~ 640, 255, and 80 nm, and the diameters of which were of ~ 85, 40, and 35 nm, respectively. All the La(OH)3 nanorods showed no effect on BMSCs viability and the blood compatibility. But the osteogenic differentiation showed a significant difference in La(OH)3 nanorods, in which Short-La(OH)3 nanorods showed the highest promoting effect on osteogenic differentiation. The potential mechanism in the osteogenic differentiation caused by three La(OH)3 nanorods was correlated with the different uptake efficiency in BMSCs and degradation in lysosome to form LaPO4. This work on La(OH)3 nanorods provides the basic data for the development of lanthanum-based nanoparticles. [ABSTRACT FROM AUTHOR]

• Capillary pressures in different directions are presented in this study. • Hydrate formation makes the skewness of capillary pressure finer slanting degrees. • The heterogeneity in hydrate formation determines capillarity in anisotropy. • The stronger capillary heterogeneity occurs in the vertical direction. The random nucleation and growth of hydrates in the pore space contribute to the heterogeneity of hydrate sediments, which results in anisotropic fluid flow. An exact forecast for capillary pressure in different directions, which governs the gas/water distribution and the volume of residual water saturation in porous sediments, is of significant importance for hydrate exploitation. In this study, the index properties of the artificial hydrate sediment were characterized through X-ray computed tomography (CT) visualization scanning. The spatial structure feature of hydrate sediment was captured via a topological pore network, which was established from CT imaging. Then, the evolution of capillary pressure in anisotropy with the formation of hydrates was simulated and discussed. The results indicated that with hydrate formation, the capillary pressure curves became steeper, representing skewness with finer slanting degrees and poor sorting. Moreover, the differences in capillary pressure with the same hydrate saturation between different directions was enlarged. Stronger capillary heterogeneity in the vertical direction represents greater heterogeneity, according to the Leverett J-Function. [ABSTRACT FROM AUTHOR]

Severe land shortage causes a higher demand for domestic and foreign land‐intensive products. As a result, resource utilization, and related environmental issues, will increase in urban areas. To this respect, the analysis of the impact of environmental regulation on urban land use efficiency helps to identify potential points for interventions designed to ensure sustainable land use. This study first introduces a theoretical framework to investigate the micro‐transmission mechanism of environmental regulation on urban land use efficiency. Our profit decision‐making model concludes that the impact of environmental regulation on urban land use efficiency is influenced by changes in the industrial structure. Empirically, our preliminary analysis suggests that in addition to population density, both formal and informal environmental regulation can promote urban land use efficiency, with a significant spatial heterogeneity across the sample regions. Further, this study shows a remarkable double‐threshold relationship between formal environmental regulation and urban land use efficiency in China. We clarify and confirm that environmental regulation promoted urban land use efficiency only when regulation intensity was higher than 0.8612. Environmental regulation increased urban land use efficiency in high‐level industrial rationalization areas, whereas it had the opposite effect in low‐level ones. Furthermore, there was a clear marginal diminishing effect of the impact of environmental regulation on urban land use efficiency when the optimization of the industrial structure was set as a threshold variable. [ABSTRACT FROM AUTHOR]

• A novel and easy-to-prepare solid substrate—Zn@ZnO@Ag chip for SERS analysis of norfloxacin was developed. • Zn@ZnO@Ag chip were prepared by facile surface oxidation combined with non-reductant method. • High SERS activity is attributed to semiconductor characteristics of ZnO and SPR properties of leaf-like AgNPs. • High selectivity, good stability and repeatability for SERS analysis. • The practical applications were achieved for antibiotics analysis. A novel and easy-to-prepare plasmonic nanoparticles doped semiconductor substrate—Zn@ZnO@Ag chip with ultra-high surface-enhanced Raman scattering (SERS) activity was fabricated for label-free, rapid and sensitive analysis of norfloxacin. The Zn@ZnO array was synthesized by surface oxidation at low temperature, followed by in-situ reduction to form leaf-like AgNPs on Zn@ZnO array without extra reducing agent, thus fabricating a Zn@ZnO@Ag chip. The ultra-high SERS activity is attributed to the synergistic effect of semiconductor characteristics of ZnO and surface plasmon resonance properties of leaf-like AgNPs. The possible enhancement mechanism was verified by density functional theory simulations. The proposed SERS method showed a wide linear range (3.0–500.0 μg/L) and low limit of detection (0.8 μg/L) for norfloxacin analysis. High sensitivity, good selectivity and acceptable recoveries (82.7–113.6%) in real sample analysis were obtained. This study offers a promising SERS chip-based platform for norfloxacin detection in the field. [ABSTRACT FROM AUTHOR]

• Recent progress of noble-free SERS substrates for SERS analysis are overviewed. • The various characteristics of the noble-free SERS substrate are presented. • The main analytical applications for noble-free SERS substrates are reviewed. • The challenges and perspectives of noble-free SERS substrates are summarized. Surface-enhanced Raman spectroscopy (SERS) has gained recognition as a potential vibrational spectroscopy technique due to its distinctive fingerprint characteristics, non-invasive nature, high sensitivity, and quick detection response. Following the initial observation of enhanced Raman signals from a pyridine molecule adsorbed on a rough Ag electrode in the 1970 s, a variety of substrates with enhanced capabilities have been explored for diverse applications. In recent times, a range of noble-free SERS substrates has been developed for broad analytical applications owing to their improved activity, inherent chemical stability, and high specificity for target molecules. This review comprehensively examines recent advances in noble-free SERS substrates, primarily focusing on main categories, fabrication strategies, basic enhancement mechanisms, corresponding SERS performance, and representative applications. Firstly, the review illustrates the fundamental working principles of SERS, including electromagnetic (EM) and chemical (CM) enhancements. Subsequently, a detailed overview of the general categories of noble-free SERS substrates is presented. These include carbon-based materials, metal oxides, transition metal dichalcogenides, transition metal nitrides/carbides, polymers, metal–organic frameworks (MOFs), MXene, Si, heterojunctions, and other noble-free SERS substrates. Next, a brief view of their typical applications in bio-analysis, bioimaging, and small molecule analysis is outlined. In the end, this review addresses the challenges and discusses perspectives, including improvement in SERS enhancement, the unification of enhancement mechanisms, and the expansion of applications. The challenges and potential avenues for future research and development are thoroughly discussed and proposed. [ABSTRACT FROM AUTHOR]

• Mechanism of ion transportation during moisture swing adsorption (MSA) of CO 2 is revealed by a transient model based on the diffusion-reaction of ions. • The homogeneous ionic transportation process under the effect of ion concentration, electrical field, and chemical equilibrium is derived and discretized using a finite difference approach in the model. • Moisture swing frequency response (MSFR) method is established for ascertaining the kinetic parameters of the ion transfer phenomenon in the model. • A concept of continuous capture of CO 2 from the air is demonstrated through the driven force of partial pressure difference of water vapor. Direct air capture of CO 2 (DAC) sufficiently mitigates atmospheric CO 2 to prevent the impacts of global warming of 1.5 °C above preindustrial levels. To overcome the challenges of the kinetics of sorbent under the ultra-low partial pressure (40 Pa) of DAC, the underlying mechanisms need to be constructed for better designs, simulations, and developments of the separation processes of carbon dioxide. Herein, a transient model based on the diffusion-reaction of ions at the molecular scale is developed for the moisture swing adsorption (MSA) process, disclosing the mechanism of mass transfer of multi-ions of sorbents. To compare the model with the experiment quantitatively, Fourier-transformed moisture-swing frequency response is applied to accurately measure the H 2 O CO 2 concentration response, ensuring a systematic approach for unknown kinetic parameters for the model. The results reveal that the gradient of water vapor causes a counter gradient of CO 2 concentration, generating the spontaneous transportation of CO 2 of the MSA membrane from one side to another. Specifically, the diffusion coefficient of HCO 3 − drives the CO 2 adsorption process predominantly, where the diffusion coefficient of HCO 3 − increases about ten times, leading to a nearly 12 times enhanced CO 2 separation rate accordingly. Notably, CO 2 adsorption kinetics can be stimulated by controlling specific ion conductivity in the moisture swing sorbent. With the enhancement of adsorption kinetics and low capital cost, the progress of CO 2 mitigation using Moisture Swing Adsorption can be achieved for direct air capture of CO 2. [ABSTRACT FROM AUTHOR]

Natural gas hydrate is recognized as an ideal substitute for traditional energy resources. Gas production from hydrate reservoirs is accompanied by the phase transition of solid hydrate, which inevitably results in changes to the microstructure of hydrate sediments. Therefore, the interaction mechanism between the microstructure and permeation characteristics of hydrate sediments must be investigated, especially permeability anisotropy. In this study, we assess the variations in permeability anisotropy during krypton hydrate formation using a pore network model and X-ray computed tomography. The results showed that absolute permeability in the vertical (k v) and horizontal (k h) directions both decreased throughout the formation process, but that the decline in k v was steeper, thus resulting in a sharp increase in the degree of permeability anisotropy (k h /k v). The relative permeability to gas was always higher in the horizontal direction than of that in the vertical direction, whereas the relative permeability to water was the opposite. Moreover, the difference in the relative permeability to water and gas between the two directions increased with the increasing hydrate saturation (S h). When extrapolating to the field-scale for hydrate field trials, we consider that horizontal wells provide a better option for gas production, especially for hydrate reservoirs with a higher hydrate saturation. • Prediction of permeability anisotropy during hydrate formation is presented. • Hydrate formation increases the degree of permeability anisotropy (k h /k v). • Difference in gas/water flow between two directions increases with high S h. • Horizontal wells are found to be a better option for gas hydrate production. [ABSTRACT FROM AUTHOR]