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• Injection parameters of H 2 -rich gas over sintering process were optimized. • Experiment and numerical simulation were used to elucidate function mechanism. • A novel method on hydrogen-rich energy application in practical plants was developed. H 2 -rich gas has been widely regarded as a promising energy to substitute fossil energy in iron ore sintering process for CO 2 reduction. This investigation mainly focused on researching the influences of H 2 -rich gas injection parameters over sintering bed on sintering performance, and elucidated the potential function mechanism through both experiment and numerical simulation. Results indicated that increasing injection concentration and prolonging injection time within a proper range improved sinter quality, and the recommended value was 0.6∼0.8 % and 8 min, respectively. Injecting H 2 -rich gas at earlier sintering stages achieved greater improvement in sintering quality compared with the ones injecting at later sintering stages, and the recommended injection area was 5∼13min. Both experiment and numerical simulation results indicated that injecting H 2 -rich improved the thermal patterns of sintering bed, with extended high-temperature areas for increasing the generation of high-strength calcium ferrite. Especially when injecting H 2 -rich gas under the recommended parameters, the heat distribution in sintering bed was optimized and the sintering quality of upper sintering layer was obviously improved. Finally, an injection method for guiding the industrial application with its essence to inject H 2 -rich at earlier sintering stages was proposed. The research findings provide a promising way for the efficient utilization of clean energy in iron ore sintering plants. [ABSTRACT FROM AUTHOR]

The rapid development of many open source and commercial image editing software makes the authenticity of the digital images questionable. Copy-move forgery is one of the most widely used tampering techniques to create desirable objects or conceal undesirable objects in a scene. Existing techniques reported in the literature to detect such tampering aim to improve the robustness of these methods against the use of JPEG compression, blurring, noise, or other types of post processing operations. These post processing operations are frequently used with the intention to conceal tampering and reduce tampering clues. A robust method based on the color moments and other five image descriptors is proposed in this paper. The method divides the image into fixed size overlapping blocks. Clustering operation divides entire search space into smaller pieces with similar color distribution. Blocks from the tampered regions will reside within the same cluster since both copied and moved regions have similar color distributions. Five image descriptors are used to extract block features, which makes the method more robust to post processing operations. An ensemble of deep compositional pattern-producing neural networks are trained with these extracted features. Similarity among feature vectors in clusters indicates possible forged regions. Experimental results show that the proposed method can detect copy-move forgery even if an image was distorted by gamma correction, addictive white Gaussian noise, JPEG compression, or blurring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid all laser-based fabrication of silicon microchannel device. • Laser engraving of microchannels, laser drilling of inlet/outlet holes, laser sintering of film heater, and laser welding for packaging. • Application in microchannel heat sink for miniaturized devices. Microchannel heat sinks have been recognized as efficient cooling platforms for thermal management of miniaturized devices because of their compact structure. Unlike most microfabrication processes, laser micromachining is a versatile direct writing method to rapidly produce microchannels in brittle substrates such as silicon wafers. In this study, an all-laser fabrication method is proposed to fabricate a microfluidic heat sink for silicon devices. Lasers are used for engraving microchannels on a silicon wafer, drilling inlet/outlet holes in quartz glass cover, and welding the Si sample and quartz glass cover. The entire fabrication process is completed within two hours. The microchannel surface is converted into a hydrophilic wall as proven by contact angle measurement, and a water flow is easily introduced to the channel as a cooling fluid. The boiling heat transfer performance of the fabricated microfluidic channel is evaluated by applying heat to the bottom of the device. A micro-heater placed underneath the Si substrate is also prepared using a laser to induce selective sintering of a conductive Ag layer. The heat generated by the heater is successfully removed by boiling heat transfer, and the critical heat flux is measured to be ∼ 55.2 W/cm2 at a water flux of 208 kg/m2s. [ABSTRACT FROM AUTHOR]

In this paper, a Canny operator-based method using PCNN (Pulse-Coupled Neural Network) is proposed for color image segmentation. The coarse location information of the salient object and the background is first estimated based on the distribution of the detected key-points. An image is then over-segmented into super-pixels and their histograms are computed. The saliency of a super-pixel is obtained according to the maximum of variance ration and Shannon entropy. Color image segmentation is implemented using PCNN based on Canny operator edge detection method. The proposed method is compared with state-of-the-art methods on the widely used dataset, and the experiments show that it overall obtains more accurate results. [ABSTRACT FROM AUTHOR]

Abstract Sensor devices using different poly(3,4-ethylene dioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) based active layers were fabricated with all solution processes. It was found the devices of pristine PEDOT:PSS presented high response to humidity change, but little response to ammonia (NH 3). In contrast, the DMSO doped PEDOT:PSS devices were nearly insensitive to humidity change, and exhibited significantly improved responsivity to NH 3. Incorporation of AgNWs into the DMSO doped PEDOT:PSS film further enhanced the responsivity to NH 3 , while maintaining insensitivity to humidity changes. The mechanisms for such different sensing properties were revealed. Finally, the fabricated NH 3 and humidity sensors using different PEDOT:PSS based films were integrated with a near field communication (NFC) chip to realize a flexible system, which was able to be attached on the packaging film for monitoring the meat freshness, with the sensing data being read out wirelessly by a smart phone. Graphical abstract Image 1 Highlights •The sensing mechanisms to ammonia and humidity of sensors using different PEDOT:PSS based active layers were revealed. •PEDOT:PSS based humidity insensitive ammonia sensors and ammonia insensitive humidity sensors were fabricated with all solution processes, respectively. •The PEDOT:PSS based ammonia and humidity sensors were integrated with a near field communication (NFC) chip to realize a smart packaging system for monitoring the meat freshness. [ABSTRACT FROM AUTHOR]

Liver fibrosis (LF) is a common reversible consequence of chronic liver damage with limited therapeutic options. Yinchen Gongying decoction (YGD) composed of two homologous plants: (Artemisia capillaris Thunb , Taraxacum monochlamydeum Hand.-Mazz.), has a traditionally application as a medicinal diet for acute icteric hepatitis. However, its impact on LF and underlying mechanisms remain unclear. This study aims to assess the impact of YGD on a carbon tetrachloride (CCl 4) induced liver fibrosis and elucidate its possible mechanisms. The study seeks to establish an experimental foundation for YGD as a candidate drug for hepatic fibrosis. LC-MS/MS identified 11 blood-entry components in YGD, and network pharmacology predicted their involvement in the FoxO signaling pathway, insulin resistance, and PI3K-AKT signaling pathway. Using a CCl 4 -induced LF mouse model, YGD's protective effects were evaluated in comparison to a positive control and a normal group. The underlying mechanisms were explored through the assessments of hepatic stellate cells (HSCs) activation, fibrotic signaling, and inflammation. YGD treatment significantly improved liver function, enhanced liver morphology, and reduced liver collagen deposition in CCl 4 -induced LF mice. Mechanistically, YGD inhibited HSC activation, elevated MMPs/TIMP1 ratios, suppressed the FoxO1/TGF-β1/Smad2/3 and YAP pathways, and exhibited anti-inflammatory and antioxidant effects. Notably, YGD improved the insulin signaling pathway. YGD mitigates LF in mice by modulating fibrotic and inflammatory pathways, enhancing antioxidant responses, and specifically inhibiting FoxO1/TGF-β1/Smad2/3 and YAP signal pathways. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalytic methane/air combustion in a micro-channel was parametrically studied. • Operating parameters correlate with the heterogeneous and heterogeneous reactions. • The heterogeneous reactions are insensitive to the inlet velocity. • The homogeneous reaction is enhanced at the increased inlet temperature. • Increasing the equivalence ratio moves the combustion zone upstream. Micro-combustion is a promising technology for addressing global energy consumption challenges; however, its practical implementation is hindered by a limited understanding of the underlying reaction characteristics. To address this, a comprehensive numerical investigation was conducted using a well-established two-dimensional (2D) steady model to examine the influence of key operating parameters (e.g., inlet velocity, equivalence ratio, and inlet temperature) on catalytic methane/air combustion in micro-channels. The results show that the heterogeneous reaction exhibits limited sensitivity to changes in inlet velocity, whereas the homogeneous reaction shows substantial enhancement with increasing inlet temperature. With the increment of inlet velocity, the peak value of stage III- heterogeneous ignition (conversion of CO to CO 2 and H 2 to H 2 O) decreases and levels off once u in ≥ 0.50 m/s. Simultaneously, the minimum value of S (the ratio of heat released by the heterogeneous reaction to that of the total reaction) decreases as well. As the equivalence ratio is increased, the combustion zone shifts towards the upstream direction. The value of S initially increases and then decreases, reaching a maximum of 17.61 % at Φ = 0.95. Raising the inlet temperature results in the upstream movement of the flame, accompanied by reduced combustion heat release, lower combustion temperature, and diminished intensity of homogeneous combustion. The influence of the heterogeneous reaction on combustion is more pronounced under operating conditions with lower inlet velocities, an equivalence ratio approaching 0.95, and higher inlet temperature. Additionally, under the condition of higher inlet velocities, an equivalence ratio close to 1.0, and elevated inlet temperature, the heterogeneous reaction aids in igniting the homogeneous reaction more effectively. [ABSTRACT FROM AUTHOR]

Surface ignition is the first and also the important step for iron ore sintering, which provides the initial source of energy to trigger the whole reactions. This investigation mainly focused on revealing the relationship between surface ignition and sintering performance, and elucidated the deep mechanism. Results indicate that the quality of sinter in the surface layer can be effectively improved by adjusting the ignition parameters. The preferred ignition parameters include ignition temperature of 1050 °C, ignition duration of 1 min and heat preservation of 1−2 min. The function mechanism of improved sinter quality is attributed to the increased high temperature duration for minerals melting, the enlarged melting zone, and the decreased cooling velocity. These changes facilitate the formation of enough adhesive phase of calcium ferrite, more of which generated in acicular morphology with high mechanical strength. Optimizing the ignition process reduced the solid fuel consumption due to the improved sintering performance, which then decreased the emission of NO and SO 2. The research findings are of great significance for providing a guide for the design of desirable ignition system and making further contributions to energy conservation and emission reduction during sintering. [ABSTRACT FROM AUTHOR]

For the practical combustion of ammonia (NH 3) in air, ammonia jet entrains the combustion product inside the furnace, and the reaction zone is diluted with a significant amount of H 2 O; thus, the impact of H 2 O on NH 3 oxidation cannot be ignored. In this study, NH 3 oxidation was conducted under N 2 and H 2 O atmospheres in a jet-stirred reactor. Experimental and numerical investigations were conducted to analyze the impact of various parameters, including the temperature, equivalence ratio, H 2 O volume fraction, and residence time. The NO formation is enhanced as T increases, while it is inhibited as Φ or X H2O increases. The N 2 O and NO concentrations are an order of magnitude when T ≤ 1375 K, and the peak N 2 O concentration occurs at T ≈ 1375 K and Φ = 0.5. The presence of 20 % H 2 O reduces NO and N 2 O concentrations by 61.5 % and 29.5 %, respectively, at Φ = 0.5 and T = 1375 K. To reduce NO x formation with an acceptable concentration of unburned NH 3 , the recommended operation condition of NH 3 oxidation is obtained. This study presents a new underlying understanding of the formation of NO x during NH 3 oxidation under N 2 and H 2 O atmospheres. • NH 3 oxidation with wide Φ and high H 2 O concentration is studied in a JSR. • 20 % H 2 O addition reduces NO concentration by 61.5 % at Φ = 0.5 and T = 1375 K. • The peak N 2 O concentration occurs at Φ = 0.5 and T ≈ 1375 K. • The optimal condition with low NO x and unburned NH 3 concentration is obtained. [ABSTRACT FROM AUTHOR]

Hydrogen-rich gas and steam are widely regarded to be of great potential to mitigate CO 2 emissions in iron ore sintering, these gases can regulate heat distribution in the sintering machines by replacing fossil fuels. However, most sintering machines only use one of the gases as the injecting medium, the potential of this technology has not been developed. In this paper, a multiple gaseous medium injection method contained natural gas and steam was experimentally investigated to solving this problem. Sintering tests were arranged to study the appropriate scheme of coupling injection and its influence on the sintering process, and the flue gas analyzer was used to detect the composition of the sintering flue gas in real time. Better sintering indexes were achieved by injecting the above two gaseous medium when the coke breeze ratio is unchanged, the results show that when 0.8 vol% natural gas is injected into the 4–14min, 0.15 vol% steam is injected into the 10–14 min, and 0.25 vol% steam is injected into the 15–18 min of sintering, the sintering yield increases by 2.42%, and the tumbler index increases by 2.72%. Under the above parameters, the coke breeze ratio can be reduced by 12.99%, the average NOx emissions decreased by 19.5%, and the average CO emissions decreased by 36.96% in the coupling injection interval (4–18min). After calculating the amount of coke breeze and natural gas in the optimal coupling injection sintering, CO 2 emissions decreased by 7.66%, about 17.15 kg/t -sinter. Moreover, the PFR model was used to simulate the associated gas phase reaction after coupling injection which shows H 2 O significantly reduced CO emissions and change the reduction pathway of NO. Generally, sintering fuel consumption and greenhouse gas emissions have also been reduced, providing theoretical support for the change of iron ore sintering energy structure. [Display omitted] • Natural gas and steam coupling injection in iron ore sintering for the first time. • The energy structure is optimized to partial replace fossil fuel with gas-based fuel. • The heat distribution and sintering speed after coupling injecting are analyzed. • PFR model shows the NO reduction pathway will change when steam is present. • CO 2 emission can be reduced by 91400 t/year with coupling injection sintering. [ABSTRACT FROM AUTHOR]

• Cervical carcinoma is a leading cause of mortality in women worldwide. • Lignans, as phytochemicals, have therapeutic potential for cancer cell lines. • An electrochemical cytosensor evaluated pinoresinol activity on HeLa cells. • Pinoresinol induced apoptosis in HeLa cells and hindered HeLa cell cycle. • MTS, flow cytometry, and fluorescent imaging confirmed the cytosensor results. A sensitive, simple, label-free electrochemical cytosensor was developed to evaluate the anticancer activity of pinoresinol against human cervical carcinoma (HeLa) cells. HeLa cells were immobilised on carboxylated multi-walled carbon nanotubes (c-MWCNTs)/gold nanoparticles (AuNPs) nanocomposite-modified glassy carbon electrodes. Scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffractometry were used to characterise the morphology, crystallinity, and composition of the nanocomposites. Cyclic voltammetry was used to characterise and optimise the cytosensor. Both c-MWCNTs and AuNPs increased the electron-transfer rate between the HeLa cells and the electrode, retaining good cell compatibility. The concentration of HeLa cells immobilised on the nanocomposite electrode exhibited a good correlation with the impedance values determined by electrochemical impedance spectroscopy in the range of 102–106 cells/mL (detection limit of 102 cells/mL) with R2 = 0.975. HeLa cells were then immobilised on the nanocomposite electrode at a concentration of 104 cells/mL, and it was used as a cytosensor. The anticancer activity of pinoresinol from Cinnamomum camphora was evaluated by determining the median inhibitory concentration using the proposed cytosensor. For comparison, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, and fluorescent imaging were simultaneously performed, which confirmed the results of the cytosensor. The cytosensor is promising for future applications in anticancer drug screening. [ABSTRACT FROM AUTHOR]

With the objectives of reducing CO 2 emissions and applying hydrogen-enriched gas in the iron ore sintering process, a mathematical model was developed to simulate the natural gas (NG) injection in the sintering process. The accuracy of the model was verified via sinter pot tests. Additionally, an environmental assessment of CO 2 mitigation was performed. Moreover, the effects of the injection quantity, location, and intensity on the sintering process were examined. Sintering process parameters were adopted to quantitatively assess the NG injection technology. The results indicated that this technology can reduce the CO 2 emissions. The CO 2 mitigation dosage is 11.75 kg/ton sinters when 15% solid fuel is replaced with NG. The melting zone thickness (MZT) and binding liquid phase amount in the upper sintering bed are gradually improved with NG injection quantity increased gradually, which indicates that the holding time of the high temperature zone in the upper bed is prolonged. Furthermore, the injection locations and intensities affect the sintering process. Earlier injection allows more heat storage and forms more binding liquid phase in the upper bed. Low intensity injection reduces the MZT of the sintering bed and negatively affects the sintering process. [Display omitted] • A model is built to simulate natural gas (NG) injection in sintering process. • Three combustion parameters are adopted to assess the NG injection technology. • Low CO 2 emissions and reasonable heat utilisation is proven for this technology. [ABSTRACT FROM AUTHOR]

Strong synergistic interactions existed between lactoferrin (LF) and α-lactalbumin (ALA) during heating at pH 7.0, leading to the formation of thermal aggregates and gels at low total protein concentration. As a result of non-covalent interactions (the decreased electrostatic repulsion and increased attractive hydrophobic attraction) and covalent interactions (in particular S-S bridge exchanges), the aggregation between unfolded Lf molecules and/or ALA molecules occurred via a co-fusion, nucleation and growth processes. The denaturation degree of LF and the concentrations of ALA affected the degree of aggregation and gelation of LF and ALA. [Display omitted] • There existed strong synergistic interactions between lactoferrin (LF) and α-lactalbumin (ALA) during co-heating. • ALA led to hydrophobic residues located in the interior of LF to be exposed further during co-heating. • New intermolecular disulfide bonds, mainly unstable ones, were formed during co-heating. • LF engaged readily in thermal aggregation, while ALA mainly assisted the LF thermal aggregation. • Co-fusion, nucleation and growth mechanisms involved in the aggregation and gelation processes. The synergistic enhancement in the thermal co-aggregation and gelation of lactoferrin (LF), a heat sensitive protein, and α-lactalbumin (ALA), a heat stable protein, was investigated at pH 7.0. Heating temperatures (70 °C and 90 °C; 30 min) and ALA concentrations (0–0.5 mM) significantly affected the structural characteristics of the resultant thermal aggregates and gels. The turbidity and size of LF-ALA thermal aggregates were increased with increasing ALA concentration; at a low total protein concentration of 0.57 mM, LF-ALA gels can be formed. The presence of ALA led to some hydrophobic residues originally located in the interior of LF to be exposed further during heating. New intermolecular disulfide bonds, mainly unstable ones, were formed between LF molecules and/or ALA molecules during co-heating. The aggregation of LF and ALA was a gradual denaturation process, accompanied by an increase in β-sheet content and decrease in α-helix content. Random spherical aggregates with large size (1–5 μm) were observed by transmission electron microscopy, clearly confirming the nucleation and growth of LF with ALA. There existed strong rheological synergism between LF and ALA, thereby leading to a large reduction in gelation times (4–11 min) with increasing ALA concentration and heating temperature. Considering these data, LF and ALA played different and indispensable roles in thermal aggregation and gelation: LF engaged readily in thermal aggregation, while ALA mainly assisted the LF thermal aggregation. Three types of mechanisms (co-fusion, nucleation and growth) involved in the aggregation and gelation processes. In all, the data of the current study has enhanced the comprehension of heat sensitive protein-heat stable protein thermal aggregation and gelation, and may help to design LF-based new ingredients for the control of food textures and delivery systems for food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]