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Summary Here we demonstrate a thermal shock synthesis method triggered by microwave irradiation for the rapid synthesis of nanoparticles on reduced graphene oxide (RGO) substrate. With properly controlled reduction, RGO has high electrical conductivity while maintaining functional groups, leading to an extremely efficient microwave absorption of ∼70%. The high utilization of microwaves results in the ability to raise the temperature to 1,600 K in just 100 ms, which is followed by rapid quenching to room temperature. The defects on the RGO are crucial for achieving this record-high microwave-induced temperature as these defects play a fundamental role in absorbing the radiation as well as the self-quenching mechanism. By loading precursors onto RGO, we can utilize rapid temperature change to synthesize nanoparticles. The nanoparticles are ∼10 nm with uniform distribution. This facile, rapid, and universal synthesis technique has the potential to be employed in large-scale production of nanomaterials and suggests a new direction for nanosynthesis.

Fixed bed reactor is widely used in the petrochemical industry. The most rigorous description of it is particle-resolved simulation. In this study, a particle-resolved CFD model coupling reaction-diffusion was developed. The gas and porous particle phase were solved separately and the data of heat and mass is exchanged across the phase interface. Detailed flow and reaction process for synthesis of vinyl acetate were investigated by this model. The results showed that the local flow was not uniform under different flow patterns, which leads to the non-uniform distributions of temperature and concentration. In addition, the intra-particle pore diffusion influenced the reactor performance. The increase of particle pore size can obviously promote average reaction rate and decrease product concentration inside particles. The proposed modeling provided deep insight for local flow and reaction-diffusion process and can be extended to entire fixed bed reactor.

The effect of soybean soluble polysaccharide (SSPS) on the pasting, gels and rheological properties of kudzu and lotus starches was investigated. The structures of starch/SSPS mixtures after gelatinization were investigated by scanning electron microscopy (SEM), wide-angle X-ray diffraction (XRD), and confocal laser scanning microscopy (CLSM). The substitution of kudzu and lotus starches with SSPS reduced the peak viscosity and increased the gel stability according to rapid visco analysis, while SSPS resulted in an increase in freeze-thaw syneresis. Indeed, the SEM analysis of the starch/SSPS samples showed small ditches on the sample surfaces. Moreover, a significant drop (P G″). The data for the steady shear viscosity were modeled with the power-law equation, and the flow behavior index (n) was n

Transition-metal oxides (TMOs) are considered as promising anode materials for lithium ion batteries. However, the poor structural stability and relatively low electronic conductivity greatly limit their application in flexible electronic devices. Herein, a 3D hierarchical high performance MnO-based flexible electrode is fabricated through vacuum-assisted layer-by-layer assembly of 1D polydopamine coated MnO2 nanowires (MnO2@PDA NWs) and 2D graphene oxide nanosheets (GO NSs), followed by a thermal reduction process. The resulting composite (MnO@C-rGO) demonstrates excellent flexibility, structure stability and manifests outstanding lithium storage performance in terms of high reversible capacity (920 mAh g−1 at 0.2 A g−1), excellent rate capability (686 mAh g−1 at 2 A g−1 and 396 mAh g−1 at 10 A g−1) and impressive cycling stability (719 mAh g−1 at 2 A g−1 without fading after 800 cycles), exceeding most of recently reported MnO-based anodes. It is proved that the freestanding flexible MnO@C-rGO anode can be successfully applied in flexible full cell, which achieves superior flexibility and maintains good electrochemical performance during mechanical deformations.

The occurrence of constipation involves the whole gastrointestinal tract. Konjac glucomannan (KGM) has been clinically proven to alleviate constipation, but its mechanism has not been fully understood. The present study aimed to investigate the excretion-promoting effect of KGM on constipated mice and the underlying molecular mechanism. In this study, the UHPLC-QE orbitrap/MS method was used to determine the metabolic phenotypes of total gastrointestinal segments (i.e., the stomach {St}, small intestine {S}, and large intestine {L}) in constipated mice treated with KGM. The results showed that KGM improved the fecal water content, body weight growth rate, and serum gastrointestinal regulation related peptide levels. The metabolomics results revealed the decreased levels of amino acids, cholines, deoxycholic acid, arachidonic acid, thiamine and the increased levels of indoxyl sulfate, histamine, linoelaidic acid etc. The KEGG pathway analysis indicated that the relaxation effect of KGM supplementation was most likely driven by modulating the expression levels of various key factors involved in biosynthesis of amino acid (i.e., phenylalanine, tyrosine and tryptophan), linoleic acid metabolism, biosynthesis of secondary metabolites, and arachidonic acid metabolism signalling pathways. The results indicated that KGM alleviates constipation by regulating potential metabolite markers and metabolic pathways in different gastrointestinal segments.

In this study, citric acid (CA) esterified canna starch was firstly synthesized with the aid of vacuum, microwave and infrared radiation treatment. The changes in structural, physicochemical properties and in vitro digestibility of the modified starch were then investigated. The maximum degree of substitution (DS) reached 0.273 and the maximum thermo-stable resistant starch (RS) content reached 86.5 %. FT-IR confirmed the esterification reaction had successfully occurred, XRD and DSC results revealed that the crystalline and endothermic peaks of the samples disappeared after CA-treated, and TGA showed that the thermal degradation temperatures were above 280 °C. SEM showed the destroyed surface of the starch granules. All modified samples were lighter and generally whiter than native canna starch in color. These results suggest that the aid of vacuum treatment, microwave and infrared radiations for CA esterified of canna starch is an effective method for preparing high content of thermally stable RS4.

To develop a more effective and safer treatment for Hyperuricemia (HUA), this research investigated the anti-hyperuricemic mechanism of KGM from the perspectives of uric acid (UA) production and excretion in rat model. After four-week experiment, KGM at 168 mg/kg did best in reducing serum UA level. The mechanism of KGM improving HUA was related to its inhibitory capacity to the activities and mRNA expression of xanthine oxidase (XOD) and adenosine deaminase (ADA) in liver. Meanwhile, KGM could also down-regulate the protein expression of uric acid transporters1 (URAT1) and up-regulate the mRNA and protein expression of urate transporter (UAT), organic anion transporter1 (OAT1) and organic anion transporter3 (OAT3) in kidney. Moreover, KGM could also alleviate the renal dysfunction caused by HUA by mitigating urate deposition, and reducing serum creatinine (Cr) and blood urea nitrogen (BUN) levels. KGM might complement existing therapies to improve HUA.

Konjac glucomannan octenyl succinate (KGOS) has excellent emulsifying and thickening properties as a new polymeric surfactant. The reaction extent of KGOS was determined by using high-performance liquid chromatography. The molecular aggregation state of KGOS was observed and analyzed by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The results showed that KGOS aggregated particles formed irregular spheres or ellipsoids, and the average particle diameter and height were approximately 30 nm and 5 nm, respectively. Thermal analysis indicated that the carbonization temperature of KGOS is slightly lower than that of konjac glucomannan (KGM). The steady shear rheology showed that KGOS solution fit to non-Newtonian fluid properties and the Carreau model, and the apparent viscosity increased with increase of KGOS concentration. The type and valence of the ions affected the apparent viscosity of KGOS solution. The trends of the dynamic mechanical spectra indicated KGOS solution could be an entanglement system. The ions had a similar effect on the dynamic modulus (G′, G″) and loss factor tanδ except for Fe3+ and H2PO4−.

The characteristics of octenyl succinic anhydride (OSA)-modified polysaccharide could be affected by its degree of reaction. Four konjac glucomannan octenyl succinate (KGOS) samples were prepared with different substitution rates (SRs) of 1.151%, 1.514%, 1.753% and 2.247%. The critical micelle concentration (CMC) of the four KGOS materials decreased with increasing SR. Fourier transform infrared (FT-IR) spectroscopy indicated that the increase in SR had little effect on the type of acyl peak. The viscosity test indicated that with SR increase, the viscosity increased slightly at low rotational speed. The emulsion capacity (EC) and stability (ES) also increased with increasing SR, but the extent of increase was not obvious when the SR exceeded 1.753%. A similar pattern was found in confocal scanning laser microscopy (CSLM) observations and ES tests of KGOS nanoemulsions. Considering the characteristics of KGOS and the economic benefits, it is preferable to prepare KGOS with an SR of 1.514% and additions of alkalizing agent and OSA (in proportion to konjac glucomannan (KGM), w/w) of 2% and 3%, respectively, during the KGOS preparation.

A uniform composite with NiCo2S4 nanoparticles anchored on graphene sheets is fabricated through an innovative one-step hydrothermal method. The XRD, Raman, XPS, SEM, HRTEM and EDS analyses are performed for characterizing the morphology and microstructure of the as-prepared NiCo2S4/graphene composite. It can be found that NiCo2S4 nanoparticles with a length of 20–50 nm were densely grown on the highly conductive graphene sheets, forming a 3D conductive network for rapid and efficient charge transport. The electrochemical performance is evaluated by CV, GCD and EIS, demonstrating that the NiCo2S4/graphene composite exhibits a very high specific capacitance (1040.6 F g−1) and greatly improved cycling stability (89.3% capacitance retention after 2000 cycles), which are due to the synergistic effect of graphene and NiCo2S4 nanoparticles. An asymmetric device has been assembled with NiCo2S4/graphene as positive electrode and graphene as negative electrode in PVA-KOH gel electrolyte solution. The as-prepared device demonstrates a energy density of 2.9 W h kg−1 with a power density of 872 W kg−1, indicating that the NiCo2S4/graphene composite can serve as a promising electrode material for asymmetric capacitor.

Atomic absorption spectrometry (AAS) and atomic fluorescence spectrometry (AFS) were used to analyze the contents of nine metal elements (Pb, As, Hg, Cd, Cr, Fe, Mn, Cu, Zn) in 100 groups of Chongqing hotpot seasoning (CHS). Meanwhile, Crystal Ball software based on Monte Carlo simulation technology was used to assess the exposure risk of the nine metal elements in CHS for people of different ages in Chongqing. In general, the average Hazard Index (HI) of the nine metal elements is 0.306 < 1, indicating no non-carcinogenic risks from these nine elements for inhabitants of Chongqing under the current consumption level of CHS. Children (ages 7–13) and adult women have higher chronic daily intake (CDI) than adult males. The carcinogenic risk of Pb, As and Cd are within the acceptable risk level (10−6 to 10−4). The sensitivity analysis suggests that the contents of the nine metal elements and daily intake (PIR) in CHS were positively correlated with the risk index, while the body weight was negatively correlated with the risk index. This study provides a scientific basis for guiding the safe consumption of Chongqing hotpot, and provides a theoretical basis for the development of safety-compliant CHS quality standards.

Carbon-black-supported nanoparticles (CNPs) have attracted considerable attention for their intriguing catalytic properties and promising applications. The traditional liquid synthesis of CNPs commonly involves demanding operation conditions and complex pre- or post-treatments, which are time consuming and energy inefficient. Herein, a rapid, scalable, and universal strategy is reported to synthesize highly dispersed metal nanoparticles embedded in a carbon matrix via microwave irradiation of carbon black with preloaded precursors. By optimizing the amount of carbon black, the microwave absorption is dramatically improved while the thermal dissipation is effectively controlled, leading to a rapid temperature increase in carbon black, ramping to 1270 K in just 6 s. The whole synthesis process requires no capping agents or surfactants, nor tedious pre- or post-treatments of carbon black, showing tremendous potential for mass production. As a proof of concept, the synthesis of ultrafine Ru nanoparticles (≈2.57 nm) uniformly embedded in carbon black using this microwave heating technique is demonstrated, which displays remarkable electrocatalytic performance when used as the cathode in a Li-O2 battery. This microwave heating method can be extended to the synthesis of other nanoparticles, thereby providing a general methodology for the mass production of carbon-supported catalytic nanoparticles.

Corn starch was esterified with octenyl succinic anhydride (OSA), in which semidry method assisted with vacuum-microwave treatment was used under the alkalescent condition. The effect of vacuum treatment on esterification was studied. The products were characterized by Fourier transform infrared (FT-IR) spectroscopy, 1H nuclear magnetic resonance (NMR), scanning electron microscopy (SEM) and X-ray diffraction. And the emulsifying properties were investigated with the emulsifying capacity (EC), emulsion droplet size and confocal laser scanning microscopy (CLSM). The degree of substitution (DS) of OSA starch increased significantly (ρ

Aim To examine the prognostic values of circulating tumor cells (CTCs) in patients with advanced lung cancer. Patients and methods A total of 98 patients with their CTCs enumerated in 2017 was recruited. Data were retrieved from medical records for comparison. Patients’ overall survival (OS) and progression-free survival (PFS) were studied using Kaplan-Meier curve with log rank test. Results Seventy-three percent of the patients were male, and nearly half of the patients (44.8%) were smokers. Most tumors were adenocarcinoma (73.4%), and about 60% of the cases were diagnosed at stage IV. Half of the patients showing less than nine CTCs. Patients’ OS were significantly associated with total CTC count (P=0.047), epithelial CTC count (P=0.027), mixed CTC count (P=0.004), and use of adjuvant chemotherapy (P=0.001). For PFS, it was strongly associated with tumor backgrounds (T stage, P=0.002; M stage, P=0.001; TMN stage, P

We investigate the quantum phase transitions (QPTs) of a four-level system in a noisy environment. The system is composed of a four-level atom which is driven by classical fields and simultaneously coupled with a quantum field mode. A second-order dissipative phase transition (DPT) is observed by combining unitary processes with dissipation dynamics. The analytical expression for the DPT in the anisotropic Rabi model is given. We demonstrate that the QPT in an open four-level system is characterized as several boundaries, which is completely different from that in a closed system. In addition, our model is robust against strong atomic spontaneous emission, providing a promising platform for observing DPT in an open system and studying the related dynamics associated with DPT.

Constipation is one of the most prevalent gastrointestinal tract diseases. Konjac glucomannan (KGM) dietotherapy can effectively relieve the clinical symptoms of patients with constipation. However, the causal relationship among KGM, constipation and different gastrointestinal microbiome (i.e., the stomach {St}, small intestine {S}, and large intestine {L}) remains poorly understood. In this study, constipated mice were treated with KGM (75, 150, 300 mg/kg bw). Results showed that KGM treatment improved the general physiological state, fecal character, small intestinal propulsive rate, gastric emptying rate, MTL and AchE activities, ET-1, 5-HT, and NO levels, and SCFA concentrations. KGM in the diets of constipated mice reduced the diversity of St and S microbiota, while increased those in the L. The KGM intervention regulated the microbiota profile, which afterwards was closer to the normal mouse group: confirmation was provided by different changes of bacteria like Lactobacillus, Bifidobacterium and Allobaculum spp et al.

A peer-to-peer (P2P) file sharing system can be reduced into a system of addition-min fuzzy relation inequalities. Concept of lexicography minimum solution is introduced and applied to such system. It is found that the unique lexicography minimum solution can be selected from the minimal solution set of the corresponding fuzzy relation inequalities. However it is difficult to find the minimal solution set which is probably infinite. In order to avoid such difficulty, we propose a so-called Circulation Algorithm to find the unique lexicography minimum solution. The algorithm is developed step by step and illustrated by a numerical application example.

Mixing multimetallic elements in hollow-structured nanoparticles is a promising strategy for the synthesis of highly efficient and cost-effective catalysts. However, the synthesis of multimetallic hollow nanoparticles is limited to two or three elements due to the difficulties in morphology control under the harsh alloying conditions. Herein, the rapid and continuous synthesis of hollow high-entropy-alloy (HEA) nanoparticles using a continuous "droplet-to-particle" method is reported. The formation of these hollow HEA nanoparticles is enabled through the decomposition of a gas-blowing agent in which a large amount of gas is produced in situ to "puff" the droplet during heating, followed by decomposition of the metal salt precursors and nucleation/growth of multimetallic particles. The high active sites per mass ratio of such hollow HEA nanoparticles makes them promising candidates for energy and electrocatalysis applications. As a proof-of-concept, it is demonstrated that these materials can be applied as the cathode catalyst for Li-O2 battery operations with a record-high current density per catalyst mass loading of 2000 mA gcat. -1 , as well as good stability and durable catalytic activity. This work offers a viable strategy for the continuous manufacturing of hollow HEA nanomaterials that can find broad applications in energy and catalysis.

Three-dimensional (3D) few-layer graphite framework shows great potential in various fields such as energy storage and electrocatalysts, owing to their porous structure, superior electronic conductivity, and good structural mechanical stability. In this work, 3D hollow few-layer graphite framework is fabricated by a temperature-driven, dynamic catalytic strategy. The in-situ generated Ni nanoparticles serve as a catalyst to promote the graphitization of carbon source. By optimizing the activating temperature, the initial small Ni nanoparticles gradually aggregate and grow into larger ones, during which they act as a dynamic catalyst to induce the construction of the 3D few-layer graphite framework along their aggregation paths. When demonstrated as the anode in Li-ion battery, the as prepared 3D few-layer graphite framework exhibits excellent electrochemical performance. The present synthetic strategy potentially represents a general method that can be extended to the construction of other carbon-based architectures for diverse applications.

High temperature synthesis and treatments are ubiquitous in chemical reactions and material manufacturing. However, conventional sintering furnaces are bulky and inefficient with a narrow temperature range (

Konjac glucomannan octenyl succinate (KGOS) has excellent emulsification properties and can potentially be used in the food industry as an emulsifier, stabilizer and microcapsule wall material. In the present study, the in vitro digestion properties and emulsification capability and stability of KGOS were studied to evaluate the transport and encapsulation characteristics of KGOS with insoluble bioactive nutrients.Confocal scanning laser microscopy (CSLM) suggested that oil droplets could be encapsulated by KGOS into regular spheres. In vitro digestion properties showed that KGOS is effective for colon-targeted transport. β-Carotene was selected as a representative lipophilic bioactive compound to evaluate the emulsification characteristics of KGOS. The loading capacity of the 0.4 mg mLThe results of this study suggested that KGOS is a good potential emulsifier and stabilizer for lipophilic bioactive nutrient encapsulation. © 2018 Society of Chemical Industry.

The physicochemical properties of Amorphophallus paeoniifolius (Dennst.) Nicolson starch (APS) and the properties of the starch plus konjac glucomannan (APS/KGM) were systematically studied. The results showed that APS had a polyhedral granular shape with sharp and protruding edges, and that the X-ray diffraction indicates an A-type pattern. Compared with corn starch (COS) and tapioca starch (TAS), the amylose content, relative crystallinity, and enthalpy of APS were higher. APS had the highest anti-α-amylase hydrolyzable property and retrogradation ratio, and it had the worst freeze–thaw stability. The pasting temperature of APS paste was the highest, then decreased with KGM addition, the peak viscosity of APS paste was higher than COS and lower than TAS, the same trend for their blends with KGM. The paste of APS, which had higher pseudoplasticity and a higher thixotropic effect than did COS and TAS, showed predominantly elastic behavior and typical weakened gel structures. The storage modulus G′ and loss modulus G″ of APS/KGM were higher than those of APS alone, and it showed more frequency dependence than did TAS/KGM but less than COS/KGM.

Konjac glucomannan (KGM) was esterified with octenyl succinic anhydride (OSA) by using microwave method under the alkalescent condition. The structure of the product—konjac glucomannan octenyl succinate (KGOS)—was characterized by means of 1H NMR spectrum, fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction, which drew conclusions that the OSA groups had been grafted onto the KGM molecular, while, incomplete deacetylation reaction occurred. All reactions occurred mainly on the surface of KGM granules, and had no significant effect on the crystallinity of the powder. In the end, the product emulsibility was also assessed, which indicated KGOS was a new kind of polymeric surfactant with good abilities both in hydrophilic and lipophilic.

This paper focuses on the nonlinear free and forced vibrations of porous sigmoid functionally graded material plates resting on nonlinear elastic foundations. Two types of porosity distributions, even and uneven, were considered. A nonlinear three-parameter foundation model was employed to estimate the plate-foundation interactions. The material properties of the plates, described by the sigmoid distribution law, were assumed to be graded in the thickness direction. All four edges of the plates were simply supported and had no in-plane displacements. Based on a higher-order shear deformation plate theory and general von Karman-type equation, the equations of motion with the effects of nonlinear elastic foundations were developed. The equations of motion were solved by an improved perturbation technique to determine the nonlinear frequencies and dynamic responses of the plates. The numerical illustrations are presented in both tabular and graphical forms to show the effects of the nonlinear foundation parameters, pore volume fraction, and material volume fraction on the nonlinear vibration and dynamic responses of the plates.

To investigate the levels of Th1/Th2 cytokines in peripheral blood of patients with primary immune thrombocytopenic purpura(ITP) before and after treatment and their clinical significance.Ninety-eight cases of ITP were treated with glucocorticoid(GC), then were divided into 2 groups: effectively treated group and uneffectively treated group according to efficacy of treatment, 40 healthy persons confirmed by health examination were selected and enrolled in control group. The levels of Th1 cytokines(IFN-γ,TNFα,IL-2) and Th2 cytokines(IL-4,IL-5,IL-10) were detected by cytometric bead array before and at 4 weeks, 3 and 6 months after treatment and the relationship among detected indexes was analyzed.Before treatment with glucocorticoid, the levels of Th1 type cytokines were in 98 patients with ITP were higher and the levels of Th2 type cytokines were lower, compared with the healthy controls(P0.05). The IL-2/IL-4 ratio was significantly higher than that of healthy controls(P0.05). After treatment, the levels of Th1 type cytokines in effectively treated group were significantly decreased and the levels of Th2 type cytokines were significantly increased, compared with level before treatment(P0.05). The IL-2/IL-4 ratio was significantly decreased after treatment for 6 months, compared with that before treatment(1.05±0.43 vs 2.53±0.72)(P0.05), but the level of Th1 or Th2 type cytokines did not obviously changed.Peripheral blood Th1 and Th2 cells express abnormally in ITP patients, ITP is a Th1 dominated disease; the change of IL-2/IL-4 ratio before and after treatment correlated with the prognosis of ITP patients, displaying clinical significance for ITP individual therapy.

Summary Chemical composition, mineral analysis, in vitro starch digestibility, and amino acid analysis of a kidney bean (Phaseolus vulgaris. L.), grown in Chongqing, China, were carried out in 2011. The results showed that the bean flour contained low reducing sugar (0.79%) and fat (2.72%), but high protein (24.8%) and starch (44.84%). Mineral analysis indicated high Mg and Ca contents with low Na/K ratio (0.04). The proportions of rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) were 39.64%, 41.46% and 18.90% respectively. And the variation in their proportions, along with prolonged heating time, showed increase in RDS, and decrease in SDS and RS, but the SDS + RS amount can still account for major parts (51.63%) of the total starch after a 90-min pre-cooking. Comparing the amino acid contents of the bean sample with recommended profile FAO/WHO/UNU (1985), the results fulfil the standard except threonine and lysine, whose contents are slightly lower than the requirements (0.93 and 0.85).

The dietary fibres (DFs) were obtained by enzymatic-chemical method from glutinous and normal millet brans from China, and their main components, neutral monosaccharide composition were analyzed. Some physicochemical properties of the two DFs were evaluated also, including the swelling capacity, water holding capacity (WHC), and oil holding capacity (OHC), et al. Data showed that the total dietary fiber content of glutinous millet bran (GMB) was 76.58g/100g, of which 69.09 g/100 g was insoluble dietary fiber (IDF) and 7.49g/100g was soluble dietary fiber (SDF), compared with normal millet bran (NMB), 73.18g/100g total dietary fiber, 65.55g/100g IDF and 7.63g/100g SDF, respectively. The DF extracted from the two raw materials both possess excellent properties, the SC values were 4.8mL/g and 4.61mL/g (37°C) for DFs of glutinous and normal samples, respectively. Also, both the two DFs exhibit obvious binding ability to the cholesterol at pH 7(GMB DF 8.14 mg/g, NMB DF 7.89mg/g).