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• We compared participants' auditory and visual distributional statistical learning. • Temporal categories were better learned in auditory compared to visual modality. • Spatial categories were better learned in visual compared to auditory modality. • Learning outcomes were correlated only for the same modality or stimulus type. • Results suggest that distributional learning is modality- and stimulus- sensitive. Statistical learning (SL) is postulated to play an important role in the process of language acquisition as well as in other cognitive functions. It was found to enable learning of various types of statistical patterns across different sensory modalities. However, few studies have distinguished distributional SL (DSL) from sequential and spatial SL, or examined DSL across modalities using comparable tasks. Considering the relevance of such findings to the nature of SL, the current study investigated the modality- and stimulus-specificity of DSL. Using a within-subject design we compared DSL performance in auditory and visual modalities. For each sensory modality, two stimulus types were used: linguistic versus non-linguistic auditory stimuli and temporal versus spatial visual stimuli. In each condition, participants were exposed to stimuli that varied in their length as they were drawn from two categories (short versus long). DSL was assessed using a categorization task and a production task. Results showed that learners' performance was only correlated for tasks in the same sensory modality. Moreover, participants were better at categorizing the temporal signals in the auditory conditions than in the visual condition, where in turn an advantage of the spatial condition was observed. In the production task participants exaggerated signal length more for linguistic signals than non-linguistic signals. Together, these findings suggest that DSL is modality- and stimulus-sensitive. [ABSTRACT FROM AUTHOR]

Drop tube furnace is a high-efficiency pyrolysis reactor, which is helpful for fundamental research of coal base poly-generation technology. In this paper, the characteristics of coal pyrolysis product at various temperature using drop tube furnace were investigated. A typical Chinese lignite Pingzhuang coal was used in current research, pyrolysis temperature ranged from 600 to 1000 °C with a step of 100 °C. The compositions of pyrolysis gas, coal tar and char were characterized and discussed in detail. Results showed that volatiles and moisture content decreased after pyrolysis, hydrophilic functional groups like carboxyl and hydroxyl also decreased, pyrolysis was a dehydration upgrading process for lignite. Specific surface area and total pore volume increased from 1.65 m2/g and 11.57 mm3/g in raw coal to 199.10 m2/g and 191.95 mm3/g in 1000 °C char, respectively. As for pyrolysis gas, when temperature increased, H 2 and CO increased obviously, other compositions like CO 2 , CH 4 and C 2 ~C 3 hydrocarbons decreased, consequently, the gross heating value of pyrolysis gas decreased from 22.5 MJ/m3 at 600 °C to 13.1 MJ/m3 at 1000 °C. High temperature pyrolysis had a high content of syngas (H 2 +CO), which can be utilized as raw material in synthetic chemical industry. There were high content of toluene in low temperature coal tar. There were more polycyclic aromatic hydrocarbons and less aliphatic chain hydrocarbons in high temperature coal tar. • ►Hydrothermal modification was used to upgrade low quality coals. • ►The nitrogen and sulfur conformation and their conversion were investigated by XPS. • ►Lower water and higher heating value were validated after hydrothermal modification. • Organic and inorganic sulfur after hydrothermal modification was investigated. • ►Hydrothermal modification may lead to lower NO x and SO 2 emission in coal utilization. [ABSTRACT FROM AUTHOR]

• 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]

[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]

[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]

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]

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]