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The patterning of transparent PET film plays an indispensable role in the application of packaging materials. However, traditional processes such as ink printing limit the pattern to a 2D plane. Recently, laser irradiation technology has been demonstrated as a potential strategy for achieving surface patterning of polymer materials. Here, we found that metallic oxide substrate can absorb laser energy and transfer it to transparent PET film through the interface, thereby improving the absorption of laser by PET. The preparation process of metallic oxide substrate is low-cost, scalable, and easy to prepare. Irradiation experiments were conducted at different energy densities, and the results show that the laser-induced patterns on the surface of PET film can be arbitrarily transformed between 2D and 3D. The PET film absorbs a large amount of heat through the interface with the substrate, which is the main factor regulating the pattern morphology. In addition, the controllability of photothermal conversion between interfaces enables laser-induced patterns to be designed locally and arbitrarily, thus achieving practical applications. The present method may open a new avenue for the application of laser patterning and meet the extensive requirements of transparent polymer materials in the fields related to surface 2D/3D pattern design.

In recent years, the efficient and clean utilization of coal has been widely concerned by scholars at home and abroad. Despite the abundance of global coal resources, the deep utilization rate of coal is still insufficient. To address this challenge, it has been explored the development and preparation of coal-based high value-added carbonaceous materials. In the present study, a novel process was developed for the preparation of graphene using biphenyl sourced from low-rank coal. Using chemical vapor deposition (CVD) technology, it was successfully implemented for us to grow high-quality graphene on copper foils. The prepared graphene products were observed and characterized using Raman spectroscopy, optical microscopy and scanning electron microscopy techniques. The results of this research provide a new perspective for the utilization of low-rank coal resources.

In order to achieve accurate and robust indoor position estimation in a wireless sensor network using particle filtering (PF)-based positioning algorithms, particle impoverishment, a problem that aroused from the traditional replicating-and-replacing resampling operation, must be well addressed. The loss of particle diversity not only degrades positioning accuracy but can also result in filtering divergence. To address this problem, this article proposes an adaptive neighbor-guided particle optimization strategy to substitute the traditional resampling operation. The strategy optimizes the distribution of the posterior particles through three steps: neighbor radius calculation, true neighbor identification, and neighbor-guided attraction. The proposed strategy is then integrated into the PF framework to form a novel positioning algorithm referred to as adaptive neighbor-guided particle optimization-based PF algorithm (ANPOPF). The test results show that the integration of the proposed particle optimization strategy considerably enhances the robustness of the PF algorithm, mitigating the effects of particle impoverishment. With the aid of the strategy, the ANPOPF algorithm achieves higher positioning accuracy compared to several existing positioning algorithms. Moreover, the ANPOPF algorithm owns an affordable computation load for most real-time applications.

Dye pollution has long been an ecological and human health issue. Activated carbon is considered to be the most promising material for dye adsorption. In this study, bamboo was used as a biomass precursor to produce activated carbon with a high specific surface area by the steam activation method. The physical activation reaction between water vapor and bamboo promotes the carbonization product to have a rich porous structure. The prepared activated carbon was investigated from the perspectives of surface morphology, elemental change, surface porosity, and surface functional groups using a variety of techniques. According to the Brunauer–Emmett–Teller analysis, the activated carbon has a high surface area (1273 m2/g) and a mesoporous structure (average pore size 3.1 nm). On this basis, the effect of activated carbon on the removal of methylene blue (MB) dye from aqueous environments was evaluated and optimized by response surface methodology (RSM). Key adsorption parameters include initial MB concentration (150–200 mg/L), adsorption time (5–120 min), adsorbent dosage (30–50 mg), adsorption temperature (5–50 °C), and solution pH (3–11). Box–Behnken design (BBD) was used for modeling and analysis. Kinetic and isotherm model studies show that pseudo-second-order model kinetics and Langmuir isotherm can better describe the process of MB dye adsorption. This study will provide new ideas for the preparation of bamboo-activated carbon and provide a model prediction basis for dye adsorption research.

Based on analysis of a large data set and supplementary sampling and analysis for hazardous trace elements in coal samples from the Huainan Coalfield, a generalized contrast-weighted scale index method was used to establish a model to evaluate the grade of coal cleanliness and its regional distribution in the main coal seam (No. 13-1) The results showed that: (1) The contents of Cr, Mn and Ni in the coal seam are relatively high and the average values are greater than 20 μg/g. The contents of Se and Hg are at a high level while most other trace elements are at normal levels. (2) The cleanliness grade of the coal seam is mainly grade III–IV, which corresponds to a relatively good-medium coal cleanliness grade. However, some parts of the seam are at grade V (relatively poor coal cleanliness). (3) Coal of relatively good cleanliness grade (grade III) is distributed mainly in the regions corresponding to the Zhuji-Dingji-Gubei coal mines and in the eastern periphery of the Panji coal mine. Coal of medium cleanliness (grade IV) is distributed mainly in the regions of the Panji-Xiejiaji and Kouzidong coalmines. Relatively poor grade coal (grade V) is distributed in the southwest regions of the coalfield and the contents of Cr, As and Hg in coal collected from the relatively poor coal cleanliness regions often exceed the regulatory standards for the maximum concentration limits.

Lead zirconate titanate (PZT) ceramics exhibit excellent piezoelectric performance, which expands piezoelectric applications scope. However, the usage of toxic PbO causes serious harm to humans and ecological environment. Lead-free environment friendly (Ba0.85Ca0.15)(Hf0.10Ti0.90)O3(BCHT) ceramics exhibit enhanced electrical properties when prepared via the powder injection molding process, relating to the polymorphic ferroelectric phases coexistence. Excellent pyroelectric properties are obtained in the BCHT ceramics, where pyroelectric anomaly and peak appear around 45 °C and 95 °C in temperature dependent pyroelectric coefficient and figures of merit, respectively, which can be attributed to the polymorphic phase transition and ferroelectric phase transition. Abnormal drastic change and large peak values of pyroelectric properties around the Curie temperature TCmake the BCHT ceramics promising application for critical temperature detection. The dielectric response contribution was analyzed by Rayleigh formula fitting, where the reversible contribution takes major role at low temperatures and the irreversible contribution takes main effect at high temperatures. The conduction activation energy is 0.71 eV for the BCHT ceramics, which correlates with the increased oxygen vacancies induced by cations evaporation during sintering.

Background: Stimuli-responsive microgels have attracted extensive investigations due to their potential applications in drug delivery, catalysis, and sensor technology. The self-assembled mcirogel films can contain different functional groups (e.g., -COOH, -NH2, -C=ONH2) to interact with specific molecules and ions in water, and their study is becoming increasingly important for developing both absorbent materials and sensor coatings. This paper is aimed to obtain a better understanding of the LbL multilayer formation of microgels and the branched PEI using the mass sensitive QCM. Additionally the influence of the temperature and pH on the formation of the microgel films can be achieved. Methods: The temperature and pH sensitive P(NIPAM-co-AA-co-TMSPMA) microgels were prepared by surfactant-free emulsion polymerization and confirmed by FT-IR, laser particle size analysis, and SEM. The obtained microgel and PEI were further used to prepare multilayer thin films by the LbL self-assembly technique monitored by QCM, and their morphology and hydrophilic properties were determined by AFM and water contact angle measurements. Results: The thermosensitive and pH sensitive P(NIPAM-co-AA-co-TMSPMA) microgels were prepared by surfactant-free emulsion polymerization. The size and swelling properties of the microgels prepared are highly dependent on the preparation conditions such as the AA and crosslinker content, and microgels showed good temperature and pH responsive properties. SEM images showed that microgels dispersed evenly on the substrate and had a uniform particle size distribution, which was consistent with the light particle size analysis results. Furthermore, multilayer films composed of the negatively charged microgels and the positively charged PEI have been built up by a facile LbL assembly method and the influence of the deposition conditions on their formation was monitored in real time by QCM. Compared to the temperature of 25 °C, the high temperature of 35°C above the phase transition temperature leads to the more adsorbed mass of microgels on the gold surface of QCM sensors. The absorbed mass values at the deposition pH 7 and 10 are 9.82 and 7.28 µg cm-2, respectively, which are much higher than 1.51 µg cm-2 of the layers deposited at pH 4. The water contact angle and AFM both confirmed the wettability properties and morphology of multilayers on the gold surface of QCM sensors. Conclusion: The formation of the multilayer films on the gold surface by the layer-by-layer deposition technique of the negatively charged microgels and the oppositely charged PEI can be achieved. The controllable multilayer formation can be attributed to the size difference, changes in the hydrophilic property and surface charge density of microgels responsive to the external temperature and pH.

An efficient methodology for the direct metal‐free azidoarylation of vinylcyclopropanes using trimethylsilyl azide as the N3‐transfer reagent is described. The reaction can be performed on a gram scale and a series of N3‐containing dihydronaphthalene derivatives (20 examples) were prepared in good to high yields under mild reaction conditions. Furthermore, three of these organic azides were selected for facile conversion into the corresponding 1,2,3‐triazoles or amino derivatives. Mild and free: An efficient metal‐free azidoarylation of vinylcyclopropanes using trimethylsilyl azide as the N3‐transfer reagent was developed, giving access to a series of N3‐containing dihydronaphthalene derivatives (20 examples) in good to high yields under mild reaction conditions.

Using bismuth oxide (Bi2O3) as a laser-marking additive and thermoplastic polyurethane (TPU) as the matrix, TPU/Bi2O3composite materials were prepared by melt blending in a torque rheometer. The sheet samples prepared from the TPU/Bi2O3composites were treated in air by scanning with a neodymium-doped yttrium aluminum garnet (Nd: YAG) pulsed laser beam at a wavelength of 1064 nm. Compared with the pure TPU sample, the laser-marked composite samples exhibited differences in marking contrast as the Bi2O3content increased from 0.1% to 1.0% based on stereomicroscope analysis. Scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, thermogravimetry analysis, and X-ray diffraction were used to characterize the laser-marked surface material of the composite samples. Furthermore, a mechanism for the laser-effected darkening of the TPU/Bi2O3composites was proposed. The results herein indicated that the addition of the Bi2O3laser-sensitive additive to TPU resulted in laser darkening of the TPU/Bi2O3composites. The marking contrast and visual appearance of the surface of the TPU/Bi2O3composites after laser irradiation was due to a synergistic effect consisting of carbonization via TPU pyrolysis and reduction of Bi2O3to black bismuth metal.

Coal samples of different ranks were selected based on geological ages and regions to investigate their thermal evolution in aggregate structure using in situX-ray diffraction (XRD) spectroscopy. Samples were heated at a rate of 10 °C min−1in the range of 25–900 °C. The XRD profiles of the coal samples displayed an evident decrease in intensity of peak at 20° (λ-band), which suggests the decomposition of oxygen-containing functional groups in the coal matrix at higher temperatures. In contrast, the peak at 26° (so-called G-band) became sharper and shifted to higher angles, which suggests a more ordered crystallite structure of coal with increasing heating temperature. Note that the integrally diffracted intensity of these two bands weakened intensely above 400 °C, which suggests that the coal aggregate structure may be loosened due to the depolymerization of the carbonaceous matrix in coal. The primary phase of weight loss for the low-rank coals took place in the range of 300–500 °C, but the high-rank coals had an obvious second pyrolysis reaction above 500 °C. Moreover, this study shows that the heating temperature effect plays a key role in the evolution of the interlayer spacing of the crystalline structure (d002) and height of the aromatic layers (Lc), whereas the diameter of the aromatic layers (La) is more dependent on coal ranks rather than heating temperature.

Based on the analyses of aluminum melt solidification and heat transfer during the process of twin-roll casting, a coupling mathematical model of thin-gauge high-speed casting was developed, which included the casting roller shell. At the same time, FEM was adopted to solve the coupling model. The temperature field, thermal stress field and strain field of aluminum melt in casting zone were simulated by this model. When the casting velocity is 7m/min, and the thickness of strip is 2 mm, in the melt zone, the temperature of melt decreases rapidly as it approaches the rollers; the surface stress of strip is larger than the central stress; In the liquid zone and mushy zone, thermal stress is relatively small; in rolling zone, thermal stress is much larger than in the former two zones, and gradually increases along exports, then gradually decreases after the peak; the outsurface strain of the casting strip is larger than the inner strain, and the thermal stress gradually increases along exports.

Nano-Twinned (NT) Cu under shock loading parallel to twin planes was investigated via nonequilibrium molecular dynamics (NEMD) simulations, with particular attention to the shock response and intrinsic deformation mechanism. During the shock compression process, a novel multi-stage phase transformation (MPT) scenario, i.e., from FCC phase to BCC phase and then to HCP phase, happens due to shock-enhanced twin boundary (TB) sliding. Both increasing the compressive strain caused by shock and decreasing the twin lamellae in the NT Cu can promote the MPT, with which the yield strength retains but the spallation strength increases. The critical shock pressure triggering the MPT depends exponentially on lamellae twin thickness (T). These new results have great potentials for improving the impact resistance of metals by tailoring their internal nanostructures.

ABSTRACT: The effects of naloxone and naloxonazine (an irreversible mu1, antagonist) administration on fetal breathing movement (FBM) patterns under control, physiologic conditions were studied in 10 fetal lambs with chronically implanted electromyogram electrodes in the diaphragm. Neither naloxone (6 mg/h) nor naloxonazine (34 mg) had any effect on the total number of diaphragmatic electromyogram bursts per hour, mean instantaneous breathing rate, or incidence of breathing. However, naloxonazine caused a more fragmented FBM pattern, as indicated by a significant increase in both the number of apneas and pauses per hour, along with decreased epoch duration. In addition, naloxonazine caused a significant reduction in the stability or regularity of the breathing rate. Naloxone had no effects on the dynamic pattern of the FBM. These results suggest that endogenous opiate peptides play a tonic role at the mu1receptor to maintain both the continuity and stability of the FBM pattern in late gestation.

The effects of naloxone and naloxonazine (an irreversible mu1, antagonist) administration on fetal breathing movement (FBM) patterns under control, physiologic conditions were studied in 10 fetal lambs with chronically implanted electromyogram electrodes in the diaphragm. Neither naloxone (6 mg/h) nor naloxonazine (34 mg) had any effect on the total number of diaphragmatic electromyogram bursts per hour, mean instantaneous breathing rate, or incidence of breathing. However, naloxonazine caused a more fragmented FBM pattern, as indicated by a significant increase in both the number of apneas and pauses per hour, along with decreased epoch duration. In addition, naloxonazine caused a significant reduction in the stability or regularity of the breathing rate. Naloxone had no effects on the dynamic pattern of the FBM. These results suggest that endogenous opiate peptides play a tonic role at the mu1receptor to maintain both the continuity and stability of the FBM pattern in late gestation.

Owing to the complexity and heterogeneity of coal during pyrolysis, the ex situ analytical techniques cannot accurately reflect the real coal pyrolysis process. In this study, according to the joint investigation of Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), the structural evolution characteristics of lignite-subbituminous coal-bituminous coal-anthracite series under heat treatment were discussed in depth. The results of the infrared spectrum of coal show that the different functional groups of coal show different changes with the increase of coal rank before pyrolysis experiment. Based on in situ infrared spectroscopy experiments, it was found that the infrared spectrum curves of the same coal sample have obvious changes at different pyrolysis temperatures. As a whole, when the pyrolysis temperature is between 400 and 500°C, the coal structure can be greatly changed. By fitting the infrared spectrum curve, the infrared spectrum parameters of coal were obtained. With the change of temperature, these parameters show regular changes in coal with different ranks. In the XRD study of coal, the absorption intensity of the diffraction peak (002) of coal increases with increasing coal rank. The XRD patterns of coal have different characteristics at different pyrolysis temperatures. Overall, the area of (002) diffraction peak of the same coal sample increases obviously with the increase of temperature. The XRD structural parameter of coal was obtained by using the curve fitting method. The changing process of two parameters (interlayer spacing (d002) and stacking height (Lc)) can be divided into two main stages, but the average lateral size (La) does not change significantly and remains at the 2.98 ± 0.09 nm. In summary, the above two technologies complement each other in the study of coal structure. The temperature range of both experiments is different, but the XRD parameters of coal with different ranks are reduced within the temperature range of less than 500°C, which reflects that the size of coal-heated aromatic ring lamellae is reduced and the distance between lamellae is also reduced, indicating that the degree of condensation of coal aromatic nuclei may be increased. Correspondingly, the FTIR parameters of coal also reflect that, with increasing temperature, the side chains of coal are constantly cracked, the oxygen-containing functional groups are reduced, and the degree of aromatization of coal may be increased.