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Ammonia (NH

Due to the small weight and large flexibility, membrane structures are prone to vibration under external excitation. Furthermore, it may affect the normal function of membrane structures. In view of the limitation of traditional perturbation method and small deflection theory in solving strongly nonlinear vibration problem of membranes. an improved multi-scale method is proposed in this paper to investigate the characteristics of strongly nonlinear vibration of membrane. Firstly, based on the large deflection theory of membrane and the improved multi-scale method, the strongly nonlinear damped vibration control equation of membrane with consideration of geometrical non-linearity is solved. Then, the analytical expressions of the frequency and displacement functions of the strongly nonlinear vibration of membranes are obtained, which are compared with the numerical results. Furthermore, the vibration characteristics of the membrane under the initial displacement are explained together with the experimental results. The results show that the improved multi-scale method is more suitable for solving the strongly nonlinear vibration of membranes than the traditional perturbation method, since the accuracy is higher. Therefore, such a discovery exhibit exposes a more accurate theoretical method for the vibration control and design of membranes.

In this study, the mechanical and electrical properties of Zn–Sb thin films with different Zn contents were focused; the corresponding improvement mechanism is also discussed. It is found that the maximum phase transition temperature of the film is 250 °C when the Zn content is about 50 at%. The crystallization activation energy of the film also reached a maximum of 4.549 eV. The micro-structure analysis result of these annealed films through XRD showed that when the Zn content is less than 50 at.%, the Sb crystallization firstly reduces the amorphous thermal stability of the material, while the film with the highest crystallization activation energy forms the ZnSb phase. Besides, adding N element greatly increases the resistance ratio of the film before and after the phase change and the phase change temperature point, the maximum temperature reaches 265 °C, and the resistance ratio reaches 104 orders of magnitude. The doping of N also increases the density of the deposited film. When the N content is less, some N elements fill the defects caused by physical deposition, increase the density of the film, and increase the phase transition temperature of the film. The N atoms in the film are more likely to bond with Zn when N content is high, forming a Zn–N bond, and even forming a Zn3N2 phase, so that the phase transition temperature of the film is lowered.

Gas sensors built with metal oxide semiconductors have attracted tremendous attention due to the growing demand for the detection of inflammable, explosive and toxic gases. Herein, to improve the sensing response, WO3 nanoparticles decorated with Ag and Pt bimetals (Ag and Pt/WO3 NPs) have been developed via combined hydrolysis and hydrothermal strategies. Such sensors prototypes show high response to acetone (Ra/Rg = 250 @ 100 × 10–6, 140 °C), which is 6.1 fold as high as that of the pristine WO3 NPs (Ra/Rg = 41 @ 100 × 10–6, 140 °C). Moreover, the recovery time of Ag and Pt/WO3 NPs was reduced from 138 to 13 s compared with that of the pristine WO3 NPs. The improved acetone sensing performance may be attributed to that the chemical and electronic sensitization of Ag and Pt to WO3 NPs increases adsorbed oxygen species, speeds up the reaction and thus boosts the sensing response. Our strategy that decoration of dual precious metals onto WO3 NPs improves the acetone sensing performance may be applied to the gas sensors of other sensing materials.

Hydrogen (H

The newly-emerged breath sensing detection of disease biomarkers (e.g., H2S and acetone) offers rapid and noninvasive early diagnosis of diseases (e.g., halitosis and diabetes). Utilizing a single sensor to monitor dual biomarkers may contribute to both miniaturized size and multi-detection if implemented, but remains challenging. Here, interconnected BiFeO3/Bi25FeO40 nanoparticles (NPs, ∼22.5 nm in diameter) synthesized via combined microwave hydrothermal and annealing methods have been developed to selectively detect dual biomarkers of halitosis and diabetes. The selective detection has been modulated by an n/p semiconducting transformation, and has been experimentally observed and theoretically interpreted, in which electron–hole pairs are modulated due to the synergistic effect of temperature-dependent adsorbed oxygen molecules and semiconducting band bending. Remarkably, the sensor prototypes enable the selective detection of both H2S (n-type mode) and acetone (p-type mode) biomarkers with superior stability and a ppb-level detection limit. Furthermore, practical human breath has been experimentally simulated. Critically, the sensors with a waterproof membrane have been tested by immersing them into water. Our strategy of the detection of dual exhaled biomarkers by a single gas sensor may contribute to the integration and miniaturization of sensors, for upcoming intelligent medical treatment.

BACKGROUND Knee stability has an important role in the gait of hemiplegic stroke patients. However, factors affecting knee stability have not been assessed concerning gait. The purpose of this study was to explore whether co-contraction of the lower limb muscles contributes to the knee stability during the stance phase of the gait cycle in hemiplegic stroke patients. MATERIAL AND METHODS A total of 30 hemiplegic stroke patients, ages 36-79 years, were instructed to walk at their natural speed. The root mean square of surface electromyography was used to measure activities of the biceps femoris and rectus femoris muscles, while the co-contraction ratio was computed based on the root mean squares. The peak angle of knee extension was acquired in the stance phase by 3D kinematic analyses. Lower limb function was evaluated using the Fugl-Meyer scale for lower limb motor assessment. RESULTS A statistically significant increase of the muscle co-contraction ratio of the involved extremity was observed compared with that of the uninvolved extremity (t=-4.066, P

The stability for a hydrogen sensor is of crucial importance under a low-temperature range (e.g., 200-400 K), especially in critical environments (e.g., aerospace). However, the "reverse sensing behavior" of Pd-based sensing materials at low temperatures limits their wide application. Herein, a three-dimensional (3D) hydrogen-sensing material of interconnected Pd nanoparticles supported on zeolite-AFI (zeolite-AFI@Pd NPs) is designed for the hydrogen sensor at low temperature. The interconnected Pd NPs of ∼15 nm in diameter are achieved onto the zeolite-AFI framework by reduction-controlled self-assembly growth, followed by partially etching-off zeolite. The 3D structure provides a larger surface ratio for improving hydrogen adsorption onto Pd, and more space for PdHx intermediate expansion, which effectively facilitates response to hydrogen and suppresses the α-β phase transition. Remarkably, there is no "reverse sensing behavior" observed in zeolite-AFI@Pd NPs, though temperature is as low as to 200 K compared with that of pristine Pd nanowires at 287 K. Furthermore, the zeolite-AFI@Pd NPs sensors yield excellent sensing response and high stability to hydrogen at temperature from 200 to 400 K. Such Zeolite-AFI@Pd NPs sensors are expected to detect hydrogen leakage, especially in critical environments of low temperature.

This work investigated the structure and antioxidant activity of Maillard reaction products of whey protein peptides grafted with galactose through ultrasound assisted water bath heating. The Maillard reaction time was 180 min including 0, 15, 30, 45, and 60 min ultrasound assisted water-bath heating performed at the beginning of the reaction. The results revealed that the intermolecular motion of the amino group and the carboxyl group of each amino acid was accelerated, and the secondary structures of whey protein peptides were changed by grafted galactose through ultrasound assisted heating. When subjected to the ultrasound treatment for 60 min, the reducing power of whey protein isolate (WPI) and conjugated whey protein peptides (WPP) reached 0.481 and 0.686, respectively. Additionally, the ABTS+ radical-scavenging activity of WPI and WPP reached 42.19% and 49.05%, respectively. These results were significantly higher (P Ga showed significant structural, differences and higher antioxidant activity than WPI Ga (P

In this study, hematite (α-Fe2O3) micro-spheres coated with ultrafine particles (MSUPs) have been obtained for sensitive acetone sensors via first hydrothermal process with NH4F as the morphological regulator and then annealing of akaganeite. The role of fluoride ion concentration in precursor solution on the morphology has been demonstrated, and the corresponding reaction mechanism was discussed as well. The α-Fe2O3 MSUPs with 0.45 M NH4F (F0.5) in the precursor solution showed the highest response towards acetone compared to other α-Fe2O3 samples. Our α-Fe2O3 MSUPs sensors have potential in sensitive acetone detection.

Smart and reliable palladium (Pd)-based sensors that are able to operate in a large temperature range especially at low temperatures are highly desired but remain challenging because of the “revers...

Indirectly monitoring halitosis via the detection of hydrogen sulfide (H

As a kind of emerging persistent organic pollutants, perfluorooctane sulfonate (PFOS) and its salts have caused global ecosystem pollution. To develop rapid, sensitive and low-cost detection method of PFOS is of great importance. In this work, a novel sensing method has been proposed for the highly selective fluorescent visual detection of PFOS in aqueous solution based on carbon dots (CDs) and berberine chloride hydrate (BH). It was found that the fluorescence of CDs decreased apparently in the presence of berberine chloride hydrate in pH 6.09 Britton–Robinson (BR) buffer solution. When PFOS was added to the system, the fluorescence was restored slightly at 448 nm and enhanced apparently at 533 nm, but no phenomenon occurred with other perfluorinated compounds. As a consequence, an obviously distinguishable fluorescence color variation (from blue to light yellow) of solution was observed. Under the optimized experimental conditions, the enhanced fluorescence intensities at 533 nm are in proportion to the concentration of PFOS in the range of 0.22–50.0 μmol/L (R2 = 0.9919), with a detection limit of 21.7 nmol/L (3σ). The proposed approach has been successfully applied to the detection of PFOS in environmental water samples with RSD ≤ 1.1%.

The metallic dopants in palladium (Pd) sensing materials enable modification of the d-band center of Pd, which is expected to tune the α–β phase transitions of the PdHx intermediate, thus improve the sensing stability to hydrogen. Here, the boosted hydrogen-sensing stability at ultra-low temperatures has been achieved with palladium/cobalt nanowires (PdCo NWs) as the sensing material. The various Co contents in PdCo NWs were modulated via AAO-template-confined electrodeposition. The temperature-dependent sensing evaluations were performed in 0.1–3 v/v% hydrogen. Such sensors integrated with PdCo NWs are able to stably detect hydrogen as low as 0.1 v/v%, even when the temperature is lowered to 273 K. In addition, the critical temperatures of “reverse sensing behavior” of the PdCo NWs (Pd82Co18: Tc = 194 K; Pd63Co37: Tc = 180 K; Pd33Co67: Tc = 184 K) are observed much lower than that of pristine Pd NWs (Tc = 287 K). Specifically, the Pd63Co37 NWs (∼37 at% Co content) sensor shows outstanding stability of sensing hydrogen against α–β phase transitions within the wide temperature range of 180–388 K, which is attributed to both the electronic interactions between Pd and Co and the lattice compression strain caused by Co dopants. Moreover, the “reverse sensing behavior” of the PdCo NWs is explicitly interpreted using the α–β phase transition model.

Objective The antifolate chemotherapy agent pemetrexed has been widely used to treat non-small-cell-lung-cancer (NSCLC), but there is no clinically validated biomarker to select patients likely to respond. The aim of this study was to assess two proteins involved in DNA repair mechanisms, uracil DNA glycosylase (UDG) and BRCA1 as potential prognostic biomarkers in NSCLC patients treated with pemetrexed-based chemotherapy. Material and methods Formalin-fixed-paraffin-embedded tumor specimens from 119 patients with advanced NSCLC treated with pemetrexed between 2004 and 2011 were retrospectively analyzed. Expression of UDG, BRCA1, and known prognostic factors ALK, TTF-1, thymidylate synthase and folylpolyglutamate synthase was assessed by immunohistochemistry using H-SCORE (product of percent stained cells and intensity of expression). Progression-free (PFS) and overall survival (OS) served as reference endpoint. Results Most NSCLC tumor samples had UDG positivity in at least 5% of tumor cells and 34% samples had more than 50% positive tumor cells. Using the median expression value as threshold, high UDG expression (H-SCORE≥75) was significantly associated with shorter median PFS (3-year PFS 7% vs. 37%, p = 0.045) and a trend for shorter OS (3-year OS 15% vs 42%, p = 0.066) compared to patients with low UDG. In multivariable Cox analysis, the association between high UDG and shorter PFS was close to statistically significant (p = 0.08) at a significance level of 0.05 after controlling for age, gender, ALK- and TTF1-status with hazard ratio of 2.1. Grouping patients according to combined UDG and BRCA1 expression, patients with a profile of UDGhigh/BRCA1high had the shortest PFS and OS compared to all other patient groups (p = 0.007 and 0.02, respectively). Conclusion Our results demonstrate an important prognostic role for high UDG expression in pemetrexed-treated NSCLC patients, in addition to its previously reported role in pemetrexed cytotoxicity. High UDG expression was predictive of shorter PFS and OS, and patients with a combined profile of UDGhigh/BRCA1high had the poorest outcome following pemetrexed treatment.

As a persistent organic pollutant, perfluorooctane sulfonate has drawn a worldwide attention. In this contribution, a novel molecularly imprinted polymer based on mesoporous silica nanoparticles was prepared for efficient separation and enrichment of perfluorooctane sulfonate in water samples. The polymer was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and N2 adsorption/desorption experiments. The static adsorption experiments and the adsorption kinetic tests were conducted. The results showed that the adsorbents had high adsorption capacity (21.10 mg/g) and short adsorption equilibration time (25 min). Meanwhile, the effect of mesoporous silica nanoparticles on the adsorption capacity was investigated. The results indicated that the mesoporous structure helped to increase the adsorption capacity of adsorbent to adsorbate. Besides, the adsorbents show good specificity and good reusability with the adsorption capacity of adsorbent toward perfluorooctane sulfonate decreasing

Macroautophagy/autophagy is considered to play key roles in tumor cell evasion of therapy and establishment of metastases in breast cancer. High expression of LC3, a residual autophagy marker, in primary breast tumors has been associated with metastatic disease and poor outcome. FIP200/Atg17, a multi-functional pro-survival molecule required for autophagy, has been implicated in brain metastases in experimental models. However, expression of these proteins has not been examined in brain metastases from patients with breast cancer. In this retrospective study, specimens from 44 patients with brain metastases of infiltrating ductal carcinoma of the breast (IDC), unpaired samples from 52 patients with primary IDC (primary-BC) and 16 matched-paired samples were analyzed for LC3 puncta, expression of FIP200/Atg17, and p62 staining. LC3-puncta+ tumor cells and FIP200/Atg17 expression were detected in greater than 90% of brain metastases but there were considerable intra- and inter-tumor differences in expression levels. High numbers of LC3-puncta+ tumor cells in brain metastases correlated with a significantly shorter survival time in triple-negative breast cancer. FIP200/Atg17 protein levels were significantly higher in metastases that subsequently recurred following therapy. The percentages of LC3 puncta+ tumor cells and FIP200/Atg17 protein expression levels, but not mRNA levels, were significantly higher in metastases than primary-BC. Meta-analysis of gene expression datasets revealed a significant correlation between higher FIP200(RB1CC1)/Atg17 mRNA levels in primary-BC tumors and shorter disease-free survival. These results support assessments of precision medicine-guided targeting of autophagy in treatment of brain metastases in breast cancer patients.

The CLRS detection characteristics of acetone dissolved in transformer oil were analyzed. Raman spectral peak at 780 cm–1 was used as the characteristic spectral peak for qualitative and quantitative analyses. The effect of the detection depth and the temperature was investigated in order to obtain good Raman signals. The optimal detection depth and temperature were set as 3 mm and room temperature. A quantitative model relation between concentration and the Raman peak intensity ratio I780/I893 was constructed via the least-squares method. The results demonstrated that CLRS can quantitatively detect the concentration of acetone in transformer oil and CLRS has potential as a useful alternative for accelerating the in-situ analysis of the concentration of acetone in transformer oil.

Furfural concentration is an important indicator for the aging diagnosis of internal paper insulation in power transformers. Surface-enhanced Raman scattering (SERS) could directly perform rapid in-situ detection without complex preprocessing steps, which makes SERS suitable for online monitoring. The application of SERS in the detection of furfural concentration in transformer oil was investigated. First, sliver nano-bulks (AgNBs) were synthesized successfully on the copper foil surface by the galvanic displacement. The electric field distributions of AgNBs were analyzed theoretically using the COMSOL software, which indicated that the AgNBs were suitable for SERS application. Then, AgNBs were used as the SERS substrate to detect standard transformer oil samples with different furfural concentrations. As a result, the Raman spectral peak at 1571 cm−1 was selected as the characteristic SERS spectral peak of furfural dissolved in transformer oil for qualitative and quantitative analyses. Subsequently, the Raman spectral peak ratio I1571/I1597 was used as the furfural function in oil to construct the quantitative analysis model using the least squares method. Results showed that SERS method could be used to analyze the furfural dissolved in transformer oil quantitatively and effectively. With further improvements of the detection limit, the SERS method will provide a useful approach to achieving rapid in-situ analysis for furfural dissolved in transformer oil.

We report zinc oxide (core) coated with alumina (shell) single-shelled nanocables (ZnO@Al2O3 NCBs) for detection of 3-hydroxy-2-butanone (3H-2B) biomarker, which was prepared via aluminum-anodic-oxide (AAO) template confined electrodeposition, chemical etching and leaving thin AAO-channel wall with broken surface. In the core/shell nanostructure, the outer Al2O3 layer protects ZnO from interference gases, while the pores allow the target gas to react with the oxygen specie on the surface of ZnO. For as-built ZnO@Al2O3 NCBs sensors, the detection limit is as low as 1 ppm, and the response value to 50 ppm 3H-2B is 37.2 at 300 °C. Moreover, the ZnO@Al2O3 NCBs show excellent selectivity and cyclic stability. Our ZnO@Al2O3 NCBs sensors in future monitoring Listeria monocytogenes.

In this work, a sensitive three-signal assay of perfluorooctanesulfonic acid (PFOS) was proposed. In pH 3.3 Britton–Robinson (BR) buffer solution, perfluorooctane sulfonate anions can react with Nile blue A (NBA) through electrostatic attraction and hydrophobic force to form 1 : 1 ion-association complexes resulting in intensity changes in the fluorescence, UV-vis absorption and resonance light scattering (RLS). There was found to be a certain relationship between the three signal changes dependent upon the concentration of PFOS. The change of absorption of NBA is proportional to the logarithm of the concentration of PFOS in the range of 0.1–4.0 μmol L−1 with a limit of detection (LOD) of 14.8 nmol L−1, and RLS intensity change is proportional to the concentration of PFOS in the range of 2.0–12.0 μmol L−1 with a LOD of 119.5 nmol L−1 and the change in the fluorescence is proportional to the logarithm of the concentration of PFOS in the range of 0.05–4.0 μmol L−1 with a LOD of 3.2 nmol L−1. Scanning electron microscopy (SEM) and zeta potential measurements were recorded in order to study the mechanism. This simple, sensitive and cost-effective fluorescence method was successfully applied in the determination of PFOS in real water samples with RSD values of ≤2.14%.

As a persistent organic pollutant, perfluorooctane sulfonate has drawn great worldwide attention. In this contribution, a novel material of magnetic molecularly imprinted polymers based on perfluorooctane sulfonate as template molecule was prepared. The magnetic molecularly imprinted polymers were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and vibrating sample magnetometry. The adsorption isotherm was measured, and adsorption kinetic tests were conducted. The adsorbents possess high recognition ability (2.460 mg/g) and short adsorption equilibration time (60 min). Besides, they show good specificity and good reusability with the adsorption capacities of adsorbent towards perfluorooctane sulfonate decreasing less than 3% after five adsorption–desorption cycles. The magnetic molecularly imprinted polymers were used successfully in the separation and enrichment of perfluorooctane sulfonate in real water sample and exhibits good prospects in environmental treatment and monitoring. This article is protected by copyright. All rights reserved

Lactobacillus rhamnosus (L. rhamnosus) was microencapsulated with Maillard reaction products of whey protein and isomaltooligosaccharide (WIMRPs) through cold gelation within emulsification system and its survival was evaluated after exposure to simulated gastrointestinal conditions. The Maillard reaction of whey protein and isomaltooligosaccharide (4:1) occurred in wet heating conditions (90 °C, 4 h) forming high molecular weight conjugate. The WIMRPs microspheres showed the highest encapsulation yield (88.88%) after cold gelation within emulsification system compared with the microcapsules produced with the mixture of whey protein and isomaltooligosaccharide (WIMIX). The shape of WIMRPs microparticles was more spherical and smooth. The microparticles WIMRPs and WIMIX had mean diameter of 183 μm and 201 μm, respectively. WIMRPs provided better protection of probiotics after exposure of the microparticles to simulated gastrointestinal conditions, with the count of 7.48 and 7.17 log10 cfu/g respectively after 90 min incubation in Simulated Gastric Fluid (SGF) and 3% bile salt solution. The microspheres could be completely released in 60 min.

For a generalized gamma random sequence, some fundamental properties and convergence rates of the distribution of its partial maximum to the Gumbel extreme value distribution are derived. The asymptotic expansions for the distribution and density of maximum from generalized gamma distribution are given under an optimal choice of normalizing constants.

The newly emerged gas sensing detection of 3-hydroxy-2-butanone (3H-2B) biomarker is deemed as an effective avenue to indirectly monitor Listeria monocytogenes (LM). However, 3H-2B sensing materials requiring critically high sensitivity and selectivity, and ppb-level detection limit, remain challenging. Here, we report the advanced gas sensors built with bismuth vanadate microdecahedron (BiVO4 MDCD) {010} facets selectively decorated with Pd nanoparticles (Pd NPs, Pd-{010}BiVO4 MDCDs) for boosted detection of the 3H-2B biomarker. Meanwhile, BiVO4 MDCDs with overall facets are randomly deposited with Pd NPs (Pd-BiVO4 MDCDs). Comparatively, Pd-{010}BiVO4 MDCD sensors show 1 order of magnitude higher response toward the 3H-2B biomarker at 200 °C. Further, Pd-{010}BiVO4 MDCD sensors enable to detect as low as 0.2 ppm 3H-2B and show best selectivity and stability, and fastest response and recovery. Density functional theory calculations reveal a lower adsorption energy of 3H-2B onto Pd-{010}BiVO4 MDCDs than those of pristine and Pd-BiVO4 MDCDs. The extraordinary Pd-{010}BiVO4 sensing performance is ascribed to the Pd NP-assisted synergetic effect of the preferential adsorption of 3H-2B target molecules, accumulated sensing agent of ionic oxygen species, and concentrated catalysts on the {010} facets. This strategy offers rapid and noninvasive detection of LMs and is thus of great potential in the upcoming Internet of Things.

One inner corridor building was constructed by computational fluid dynamics (CFD) software and a series of CFD simulations were conducted in the building with/without a vent on the stairwell for different negative pressure differences induced by the surrounding wind. The result shows that the area affected by smoke is significantly decreased when the vent is set on the stairwell and the height of neutral plane increases significantly. However, it will increase the spread trend of smoke in low floors. The surrounding wind will produce negative pressure differences at the vent. For the high floors, with the increasing of negative pressure difference, the area affected by smoke is further reduced, but the degree of reduction is not obvious. For the low floors, the trend of smoke spread has not been alleviated with the increasing of negative pressure difference.

Galactose was grafted onto whey protein isolate (WPI) and whey protein hydrolysates (WPHs) via the Maillard reaction (95 °C, 0–4 h). The pH, browning intensity, structure, functional properties and antioxidant activity of conjugates were evaluated. The pH, browning and degree of conjugation were at maximum after heating for 4 h. The Maillard reaction changed the WPI and WPHs to a looser secondary structure. Conjugates of WPI and WPHs with galactose had higher water holding capacity, foaming capacity and stability, and antioxidant activity. Compared with the WPI-Galactose conjugates, WPH-Galactose conjugates showed better functional properties and higher antioxidant activity, and its highest reducing power was 0.923; ABTS+ radical scavenging ability was 69.81%; hydroxyl radical scavenging ability was 89.05%. These findings indicate that the covalent conjugation of WPH-Galactose conjugates can be used as a potential ingredient and a novel wall material to encapsulate bioactive compounds.

A simple, highly sensitive and selective assay method has been developed for the determination of perfluorooctane sulfonate (PFOS), a kind of emerging persistent organic pollutant, which is bio-accumulative, resistant to degradation and toxic. It was found that PFOS can form complexes with protonated Janus Green B (JGB) through electrostatic interaction in pH 5.8 citric acid–sodium citrate (CA–NaCA) buffer medium resulting in a remarkable enhancement of the resonance light scattering (RLS) intensity of the system. The study shows that the maximum scattering wavelength is located at 319.0 nm and the enhanced RLS intensities are in proportion to the concentration of PFOS in the range of 0.05–9.0 μmol L−1 (R2 = 0.9958), with a detection limit of 5.6 nmol L−1 (3σ). Under the same experimental conditions, various perfluorinated compounds (PFPrA, PFBA, PFPeA, PFHeA, PFHpA, PFOA, PFNA, and PFBS) and JGB interactions were studied and the scattering signal changes very little. Based on the above discussion, a simple, highly sensitive and selective resonance light scattering analysis method was established for the detection of PFOS. In this work, the optimum reaction conditions were investigated. The reaction mechanism between JGB and PFOS was also studied by the absorption spectrum, scanning electron microscopy (SEM), the combination ratio and so on. This method is successfully applied to the selective detection of PFOS in environmental water samples with RSD ≤2.7%.

Summary The effect of glycosylation treatment coupled with microwave heating (MH) on gel properties and structure change of casein were investigated. Conjugation was confirmed by electrophoresis. Protein disulphide bonds were broken by microwave irradiation to create an increase first and a decrease later in free sulfhydryl contents with time, thereby inducing subunit disaggregation. Also, the exposure of hydrophobic core residues was increased in MH-treated casein, which brings about protein disaggregation and unfolding. It showed that graft reactions by MH had much faster than those by water bath heating (WH). The content of disulphide bonds is 7.2% and 6.0% in the casein–glucose and casein–β-cyclodextrin, respectively, treated by MH which was reduced significantly than that of treated by WH. Moreover, MH can increase the hardness of the gel. Consequently, MH could improve the efficiency of the reaction and gel properties.