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We demonstrate the structure, spectroscopy, and laser performance of an Er3+ and Pr3+ co-doped LuYSGG crystal grown by the Cz method. The XRD result shows that it belongs to the cubic system with the space group Ia3¯d. A refractive index curve in the range of 320–3000 nm is obtained by fitting the Sellmeier equation. The lifetimes of the 4I13/2 and 4I11/2 levels are 0.871 and 0.728 ms, and the ratio is reduced obviously from 3.4 to 1.2 due to the doping of deactivator Pr3+. In CW mode, a maximum output power of 1059 mW is achieved with a slope efficiency of 17.58% and laser center wavelength of ∼2.8 μm. Beam quality factors of 1.40/1.34 are achieved. The results suggest that the Er,Pr:LuYSGG crystal is a potential candidate for generating a high-power mid-infrared laser and can be applied in irradiation environments. [ABSTRACT FROM AUTHOR]

Whether the oilfield sewage index can reach the reinjection specification is a crucial issue that is urgently need to be solved in polymer flooding systems. Thus the coagulability and floc morphology development of dual coagulants was systematically studied in different pH oily wastewaters. Acidification improved the deprotonation ability of coagulant. Hydrophobic associative polyaluminum silicate-poly dimethyl diallyl ammonium chloride (PASSC-PD) resolved the problem of excessive acid addition. The dual coagulants prepared not only preserved the high charge density of polyaluminum silicate (PASS) itself but also made it have the hydrophobic association and strong bridging ability. Besides, PASSC-PD was compared with hydrophobic associative polyaluminum silicate (PASS-C), PASS, and poly dimethyl diallyl ammonium chloride (PDMDAAC) pertaining to the polymer flooding oily sewage of Daqing Oilfield. The coagulation result demonstrated that PASSC-PD exhibited more advantageous turbidity and oil removal efficiencies than PASS-C, PASS, and PDMDAAC. The floc morphology result showed that adding dual coagulant made the petal-like floc of oily sewage larger at the pH value of 6. Furthermore relevant results evidenced that the coagulant had more successful fruits of turbidity removal of 96.5% and oil removal of 96.3% under weak acid conditions. These can satisfy the reinjection condition of oily sewage. [ABSTRACT FROM AUTHOR]

We demonstrate the temperature distribution, optical and laser performances of a YAP/Tm:YAP/YAP composite crystal fabricated by thermal bonding technology. The thermal distribution simulations show that the bonded crystal possesses a higher thermal dissipation efficiency than that of the unbonded one. The wavefront distortion of the bonded YAP/Tm:YAP crystal is close to the unbonded Tm:YAP, indicating a high bonding quality. The optical transmission spectra and absorption loss suggest that the bonding region is a uniform transition and almost without scattering interface. Moreover, compared with the un-bonded Tm:YAP crystal, a maximum average output power of 41.2 W and slope efficiency of 49.5% are achieved on the bonded crystal, which are increased by 28.4% and 21.0%, respectively. Therefore, the 1.94 μm laser performance can be effectively improved by combining pure YAP crystals on the Tm:YAP crystal as end-caps. [ABSTRACT FROM AUTHOR]

We use the multiband Fe-based superconductor (FeSC) Ba0.5K0.5Fe2As2 and the conventional superconductor Nb to fabricate a hybrid Josephson junction where an Al layer serves as a highly transparent barrier. Detailed electrical transportations are studied including the Shapiro steps and the Fraunhofer-like pattern, which indicate strong Josephson effects. An unusual temperature-dependent critical current was observed, which cannot be well described by the conventional Ambegaokar–Baratoff relation. We utilize a model considering both multiband properties in the FeSC and the conventional superconductor/normal metal/superconductor Josephson junction theory, proving that this temperature dependence on critical current is attributed to the barrier transparency of the Josephson junction. We hope our studies can be a reference for the applications or physics research of FeSC Josephson junctions. [ABSTRACT FROM AUTHOR]

The nonreciprocal Josephson junction, the Josephson diode, opens a door for superconducting circuit technology. Here, we report on nonreciprocal behaviors in Nb/Au/NbSe2 Josephson junctions. The strong asymmetry could be seen in the current–voltage characteristics, which most likely arises from time symmetry breaking due to Abrikosov vortices, indicated by an asymmetric Fraunhofer pattern. The nonreciprocal microwave responses are systematically investigated compared to a numerical simulation based on a resistively and capacitively shunted junction model, which could well capture the asymmetric behaviors and rule out some artifacts such as other parasitic Josephson-like structures. Based on the nonreciprocal microwave responses, we put forward a proposal for a switchable Josephson diode controlled by an external microwave, which might provide an opportunity for next-generation microwave-related superconducting circuits. [ABSTRACT FROM AUTHOR]

The fundamental properties of dislocations in diamond-structured Si and sphalerite-structured GaAs, InP and CdTe are investigated based on lattice theory of dislocation, hoping to provide some theoretical references in improving the properties of related materials. The influences of the surface effect(SE) and elastic strain energy on the structure and mechanical property of dislocation are discussed systematically. After considering the SE, the core width of dislocation becomes wider due to the elastic interaction between atoms becomes stronger. Compared to glide partial dislocation, the correction of SE to shuffle dislocation is more obvious. Both the SE and the elastic strain energy affect the energy barrier and Peierls stress of dislocation. The influence of SE on energy barrier and Peierls stress mainly results from the misfit energy and elastic strain energy become lower when the core of dislocation becomes wider. While the influence of elastic strain energy on energy barrier and Peierls stress mainly results from the cancellation between misfit energy and elastic strain energy for they possess comparable amplitudes but opposite phases. In addition, it is deduced that for the studied crystals, the shuffle dislocations control the deformation at medium and low temperatures, while glide partial dislocations are responsible for high temperature plasticity. [ABSTRACT FROM AUTHOR]

Efficient purification of oily sewage, recycling, and standard discharge have become key issues for the sustainable development of oil fields. In this study, the surface of PPFS was organically modified by a silane coupling agent. Then, covalently bonded cationic block inorganic-organic composite coagulant was prepared by chosen sodium polyacrylate as the template. This unique structure significantly enhances the positive charge and molecular chain length of the coagulant, thus improving its ability to perform charge neutralisation, adsorption bridging, and sweep coagulation. The characteristic functional groups and thermophysical properties of the composite coagulant were analysed by FTIR and thermogravimetric analysis. The transformation of random copolymers to block copolymers was determined by 1 H NMR, thus confirming the successful synthesis of the cationic block structures. The turbidity removal and oil removal properties of oily sewage were investigated by coagulation experiment. The Zeta potential, dynamic and static light scattering, and field emission scanning electron microscopy (SEM) were used to study the effect of composite coagulants on the microscopic morphology and coagulation of flocs. Finally, the coagulation mechanism of the compound coagulant was analyzed with the dynamic change of the particle size of the flocs. The cationic block structure in TP(AM-DAC-PPFS) can effectively neutralise the negative charges on the surface of impurity particles and emulsified oil. The optimal dosage of TP(AM-DAC-PPFS) was 30 mg·L−1, at which the turbidity and oil removal rates can reach 98.3% and 93.8%, respectively. [Display omitted] • The covalently linked composite coagulant TP(AM-DAC-PPFS) was successfully prepared. • The cationic block structure increases the coagulation capacity and avoids polymer agglomeration. • The organic molecular chain destroys the structure of the emulsified oil droplets. • Coagulation mechanism of charge neutralization, adsorption bridging and sweeping is improved synergistically [ABSTRACT FROM AUTHOR]

Mobile videos contain a large amount of data, where the information interesting to the user can either be discrete or distributed. This paper introduces a method for fusing 3D geographic information systems (GIS) and video image textures. For the dynamic fusion of video in 3DGIS where the position and pose angle of the filming device change moment by moment, it integrates GIS 3D visualization, pose resolution and motion interpolation, and proposes a projection texture mapping method for constructing a dynamic depth camera to achieve dynamic fusion. In this paper, the accuracy and time efficiency of different systems of gradient descent and complementary filtering algorithms are analyzed mainly by quantitative analysis method, and the effect of dynamic fusion is analyzed by the playback delay and rendering frame rate of video on 3DGIS as indicators. The experimental results show that the gradient descent method under the Aerial Attitude Reference System (AHRS) is more suitable for the solution of smartphone attitude, and can control the root mean square error of attitude solution within 2°; the delay of video playback on 3DGIS is within 29 ms, and the rendering frame rate is 34.9 fps, which meets the requirements of the minimum resolution of human eyes. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The purpose of our study is to present a method combining radiomics with deep learning and clinical data for improved differential diagnosis of sclerosing adenosis (SA)and breast cancer (BC). METHODS: A total of 97 patients with SA and 100 patients with BC were included in this study. The best model for classification was selected from among four different convolutional neural network (CNN) models, including Vgg16, Resnet18, Resnet50, and Desenet121. The intra-/inter-class correlation coefficient and least absolute shrinkage and selection operator method were used for radiomics feature selection. The clinical features selected were patient age and nodule size. The overall accuracy, sensitivity, specificity, Youden index, positive predictive value, negative predictive value, and area under curve (AUC) value were calculated for comparison of diagnostic efficacy. RESULTS: All the CNN models combined with radiomics and clinical data were significantly superior to CNN models only. The Desenet121+radiomics+clinical data model showed the best classification performance with an accuracy of 86.80%, sensitivity of 87.60%, specificity of 86.20% and AUC of 0.915, which was better than that of the CNN model only, which had an accuracy of 85.23%, sensitivity of 85.48%, specificity of 85.02%, and AUC of 0.870. In comparison, the diagnostic accuracy, sensitivity, specificity, and AUC value for breast radiologists were 72.08%, 100%, 43.30%, and 0.716, respectively. CONCLUSIONS: A combination of the CNN-radiomics model and clinical data could be a helpful auxiliary diagnostic tool for distinguishing between SA and BC. [ABSTRACT FROM AUTHOR]

In this article, we study anisotropic immersed finite element (AIFE) methods for the elliptic interface system. After establishing the existence and uniqueness of the weak solution, we construct a linear AIFE method for solving the interface system. Different from the scalar problem, the jump conditions for each unknown function are coupled together in the anisotropic problem considered here. Through defining suitable interpolations, we deduce the error estimates in L2‐$$ {L}^2\hbox{-} $$ and H1‐norms$$ {H}^1\hbox{-} \mathrm{norms} $$ for the proposed AIFE method. Moreover, we show some numerical experiments to verify the correction of the theoretical predictions. [ABSTRACT FROM AUTHOR]

For thousands of years, caries, periodontitis and mucosal diseases, which are closely related to oral microorganisms, have always affected human health and quality of life. These complex microbiota present in different parts of the mouth can cause chronic infections in the oral cavity under certain conditions, some of which can also lead to acute and systemic diseases. With the mutation of related microorganisms and the continuous emergence of drug-resistant strains, in order to prevent and treat related diseases, in addition to the innovation of diagnosis and treatment technology, the development of new antimicrobial drugs is also important. Catechins are polyphenolic compounds in green tea, some of which are reported to provide health benefits for a variety of diseases. Studies have shown that epigallocatechin-3-gallate (EGCG) is the most abundant and effective active ingredient in green tea catechins, which acts against a variety of gram-positive and negative bacteria, as well as some fungi and viruses. This review aims to summarize the research progress on the activity of EGCG against common oral disease-associated organisms and discuss the mechanisms of these actions, hoping to provide new medication strategies for the prevention and treatment of oral infectious diseases, the future research of EGCG and its translation into clinical practice are also discussed. [ABSTRACT FROM AUTHOR]

This study is oriented towards machine autonomous mapping and the need to improve the efficiency of map point symbol recognition and configuration. Therefore, an intelligent recognition method for point symbols was developed using the You Only Look Once Version 3 (YOLOv3) algorithm along with the Convolutional Block Attention Module (CBAM). Then, the recognition results of point symbols were associated with the point of interest (POI) to achieve automatic configuration. To quantitatively analyze the recognition effectiveness of this study algorithm and the comparison algorithm for map point symbols, the recall, precision and mean average precision (mAP) were employed as evaluation metrics. The experimental results indicate that the recognition efficiency of point symbols is enhanced compared to the original YOLOv3 algorithm, and that the mAP is increased by 0.55%. Compared to the Single Shot MultiBox Detector (SSD) algorithm and Faster Region-based Convolutional Neural Network (Faster RCNN) algorithm, the precision, recall rate, and mAP all performed well, achieving 97.06%, 99.72% and 99.50%, respectively. On this basis, the recognized point symbols are associated with POI, and the coordinate of point symbols are assigned through keyword matching and enrich their attribute information. This enables automatic configuration of point symbols and achieves a relatively good effect of map configuration. [ABSTRACT FROM AUTHOR]

The aim of present work is to evaluate pyrolysis characteristics of poly(methyl methacrylate) (PMMA) and its blends with sugarcane bagasse (SB) contents of 10 and 20 mass % for the purpose of exploring the effect of SB on pyrolysis of PMMA. Non-isothermal pyrolysis determinations of three PMMA samples were performed thermogravimetrically and the initial pyrolysis temperatures of two PMMA blends are significantly lower than that of pure PMMA while the main pyrolysis shifts to higher temperature range. Using model-free isoconversional methods, pyrolysis activation energies calculated are varying within 71.7 ~ 154.0, 107.8 ~ 192.0 and 121.3 ~ 171.0 kJ·mol−1 for PMMA and its 10 or 20 mass % SB blends, respectively. The added SB turns to increase the activation energy of PMMA and thus make pyrolysis of PMMA become more arduous to accomplish. With the model-fitting method, the order-based F2/3, F3 and F3 chemical reaction models are found to be the most appropriate pyrolysis mechanisms for PMMA and its 10 or 20 mass % SB blends, respectively. Accordingly, their pre-exponential factor values are estimated to separately span in the range of 3.23 × 104 ~ 1.76 × 1011, 3.52 × 108 ~ 7.63 × 1016 and 1.55 × 1010 ~ 1.13 × 1015 min−1. The findings acquired from present work can provide necessary information for performing potential pyrolysis designs of PMMA and its biomass blended wastes. [ABSTRACT FROM AUTHOR]

• PPFS-PAD-RGO compound coagulants were successfully prepared. • The coagulability of PPFS-PAD-RGO has been enhanced. • PPFS-PAD-RGO has certain demulsification ability. • The oil content of oily sludge is reduced. During oil extraction, a substantial volume of oily sewage (water-in-oil emulsion) is generated. The existence of emulsified oil diminishes the effectiveness of conventional coagulants used for purification. Furthermore, coagulants frequently precipitate emulsified oil as impurities, leading to resource wastage. Hence, there is an urgent need to develop multifunctional coagulation/demulsification agents that are environmentally safe. In this study, we synthesized the branched-chain compound coagulant (PPFS-PAD-RGO) and investigated its coagulation and demulsification properties. The results of dynamic and static light scattering and FTIR show that chitosan grafted onto the surface of modified PPFS forms a dendritic flocculation system. In addition, PPFS-PAD is fixed to a reduced graphene oxide carrier with a high specific surface area, which improves the positive charge density and dispersion of the coagulant. The layered structure amplifies the effect of adsorption bridge formation and net aggregation. At a concentration of 80 mg/L, PPFS-PAD-RGO exhibited a turbidity removal rate of 96.15 % and demulsification rate of 74 %. By comparing the structure of PPFS, it was found that the floc volume of PPFS-PAD-RGO is larger. This demulsification ability is mainly attributed to an amine matrix in the chitosan extension chain, which destroys the oil–water interface of the oil-in-water emulsion and induces demulsification. The introduction of RGO increases the local concentration of coagulant molecules. Therefore, the coagulation effect of PPFS-PAD-RGO in oily sewage is attributed to the introduction of demulsifier groups and nanomaterials, which strengthen the synergistic effect of charge neutralization, bridge adsorption and sweeping. [ABSTRACT FROM AUTHOR]

• A method of gravity coagulation was proposed. • The covalently linked coagulant microcapsules was successfully prepared. • The coagulant capsule has able to release its contents slowly upon water impact. • The mechanism of The coagulant capsule was studied. If untreated, oilfield sewage generated during the oil exploitation process can lead to severe environmental pollution. The coagulation/flocculation process plays a pivotal role in the comprehensive treatment of oilfield sewage on a large scale, yet traditional methods exhibit significant limitations. To address the disparity between laboratory experiments and large-scale implementation, this study introduces an innovative coagulant microcapsule. Prepared under gentle conditions, these microcapsules effectively eliminate colloidal particles from water when introduced at the coagulation tank inlet. Featuring a core–shell structure, coagulant microcapsules demonstrate controlled content release upon contact with water. The coagulation process occurs as sewage enters the coagulation tank. The core of the coagulant microcapsule consists of the inorganic polymer coagulant (PASS-C16) with hydrophobic association capabilities. Upon contact with sewage at a specific flow rate, the coagulant is released gradually from the microcapsule. Upon reaching the bottom of the coagulation pool, the coagulant comes into full contact with colloidal particles, influenced by gravity. Ultimately, through integration with Fluent simulation and analysis of floc particle size changes, it was determined that the primary mechanisms of coagulant capsules in aquatic conditions involve charge neutralization and bridging adsorption. The sweeping action is effective only when the test water tends to be static. This technology is viable for application in the coagulation sedimentation tanks of diverse sewage treatment plants. Gravity coagulation demonstrates potential as a replacement for conventional mechanical mixing methods, offering increased efficiency and potential energy savings in various water treatment processes. [ABSTRACT FROM AUTHOR]

To improve the effect of regional financial and economic data processing, this study combines the distributed decoding technology to construct the regional financial data processing system. Furthermore, this study combines the technical characteristics of cooperative communication and unitary space-time codes to design a non-differential distributed space-time code based on cyclic unitary matrix groups. In addition, this study uses the particularity of trigonometric functions to design a non-differential distributed space-time code based on trigonometric functions. Finally, according to the characteristics of the distributed space-time code of trigonometric functions, this study obtains a decoding algorithm with low decoding complexity and uses MATLAB to conduct simulation experiments to verify the financial data processing and economic analysis effect of the system in this study. The experimental analysis results show that the regional financial and economic data processing system based on distributed decoding technology proposed in this study can play an important role in the analysis of financial and economic data. [ABSTRACT FROM AUTHOR]

The CO 2 capture and separation performances are enhanced by improving structural polarity and providing CO 2 adsorption sites through introduced functional groups and Li. There is a synergistic effect between these modifications in improving performances. Notably, TpPa-SO 3 Li demonstrates the highest CO 2 capture capacity of 136.11 cm3 cm−3, along with the CO 2 over N 2 /CH 4 selectivity of 264.22/164.38, respectively. [Display omitted] • CO 2 capture and separation performances are evaluated in TpPa COFs modified by functional group and Li using GCMC and DFT. • There is a synergistic effect between functional groups and metal Li in enhancing the selective CO 2 capture performance. • TpPa-SO 3 Li exhibits the best CO 2 capture capacity of 136.11 cm3 cm−3 with the CO 2 over N 2 /CH 4 selectivity of 264.22/164.38, respectively. • Improved structural polarity and additional metal adsorption sites are the main reasons for optimized performances. Covalent organic frameworks (COFs) have emerged as promising materials for CO 2 capture and separation owing to their exceptional structural stability. Herein, grand canonical Monte Carlo simulation (GCMC) and density functional theory (DFT) were used to first screen the most favorable functional group in the COFs consisting of 1,3,5-triformylphloroglucinol (Tp) and p-phenylenediamine (Pa) functionalized with –OH, –COOH, and –SO 3 H, respectively (TpPa-X). Subsequently, the H atoms of –SO 3 H, the best functional group, were replaced by Li atoms to form –SO 3 Li, revealing the synergies of functional group –SO 3 H and Li modification on selective CO 2 capture. TpPa-OLi/COOLi were also constructed to confirmed the universality of this synergistic effect. The introduction of functional groups enhanced the CO 2 capture and separation performances by creating a more suitable pore environment. The Li introduction increased the structural polarity and provided strong adsorption sites, further improving the selective CO 2 capture performance. Notably, TpPa-SO 3 Li exhibited a remarkable CO 2 adsorption capacity of 136.11 cm3 cm−3 with the CO 2 over N 2 /CH 4 selectivity of 264.22/164.38, respectively, at 298 K and 1.0 bar. Structural stabilities, pore characteristics, gas adsorption distribution, isothermal adsorption heat, and interactions were adopted to reveal the synergistic effect between functional groups and Li in enhancing CO 2 capture and separation. [ABSTRACT FROM AUTHOR]

In this research project, we first synthesized the magnetic manganese nanocatalyst by immobilizing the MnCl2 on the surface of magnetic Fe3O4 nanoparticles modified with catechol and piperazine/phenanthroline ligand [Fe3O4@Catechol/PZ-Phen-MnCl2], then we evaluated its catalytic performance in the synthesis of propargyl amines through the A3 and KA2-coupling three-component reactions aromatic aldehydes or ketones, with alkynes, and amines. FT-IR, SEM, TEM, EDX, XRD, TGA, VSM, ICP-OES and elemental mapping analyzes confirmed the successful synthesis of Fe3O4@Catechol/PZ-Phen-MnCl2 nanocatalyst. The results of the coupling reactions confirmed that the Fe3O4@Catechol/PZ-Phen-MnCl2 nanocomposite is a very efficient catalyst for the preparation of various derivatives of propargyl amines. This method has significant features compared to the previous methods, which can be mentioned as follows: synthesis of products with very high efficiency, carrying out the reaction under mild conditions and compatible with the environment, using green and recyclable catalyst, can being applicable to a wide range of substrates and providing NMR analysis for all propargyl amine products.Graphical Abstract: In this research project, we first synthesized the magnetic manganese nanocatalyst by immobilizing the MnCl2 on the surface of magnetic Fe3O4 nanoparticles modified with catechol and piperazine/phenanthroline ligand [Fe3O4@Catechol/PZ-Phen-MnCl2], then we evaluated its catalytic performance in the synthesis of propargyl amines through the A3 and KA2-coupling three-component reactions aromatic aldehydes or ketones, with alkynes, and amines. FT-IR, SEM, TEM, EDX, XRD, TGA, VSM, ICP-OES and elemental mapping analyzes confirmed the successful synthesis of Fe3O4@Catechol/PZ-Phen-MnCl2 nanocatalyst. The results of the coupling reactions confirmed that the Fe3O4@Catechol/PZ-Phen-MnCl2 nanocomposite is a very efficient catalyst for the preparation of various derivatives of propargyl amines. This method has significant features compared to the previous methods, which can be mentioned as follows: synthesis of products with very high efficiency, carrying out the reaction under mild conditions and compatible with the environment, using green and recyclable catalyst, can being applicable to a wide range of substrates and providing NMR analysis for all propargyl amine products. [ABSTRACT FROM AUTHOR]

The CO 2 capture and separation performance is enhanced by the improved structural polarity and additional adsorption sites created by anchoring alkali metal Li/Na/K. And the increase shows a positive correlation with AM concentration. Specially, UPC-6Li presents the best CO 2 capture capacity of 221.64 cm3 cm−3, along with the CO 2 over N 2 /CH 4 selectivity of 308/206, among UPC-AMs. [Display omitted] • CO 2 capture and separation performance were evaluated in 2D-COFs anchored by different concentration alkali metal (Li, Na, and K). • UPC-6Li exhibited the best CO 2 capture capacity of 221.64 cm3 cm−3 and CO 2 over N 2 /CH 4 selectivity of 308/206. • Improved structural polarity and additional metal adsorption sites are the main reasons for optimized performance. The development of advanced adsorbents with high CO 2 capture and separation performances is essential for decreasing atmospheric CO 2 concentration. Herein, grand canonical Monte Carlo and density functional theory were employed to investigate the adsorption and separation properties of CO 2 , N 2 , and CH 4 in 2D covalent organic framework (COFs) anchored by alkali metal (AMs) Li, Na, and K (UPC-nAMs, n = 3 or 6) at 298 K and 0–1.0 bar. The anchoring of AMs formed favorable adsorption sites, endowing UPC-nAMs with better CO 2 capture and separation performances. This effect was more evident with an increase in Li/Na/K concentration. The CO 2 adsorption capacity of UPC-6Li/Na/K was ∼ 221.64, 188.28, and 140.50 cm3 cm−3. The smaller atomic size of Li occupied less adsorption space, resulting in the highest CO 2 capture capacity of 221.64 cm3 cm−3 with selectivity of 308/206 over N 2 /CH 4 in UPC-6Li at 298 K and 1.0 bar. Structural stability, pore characteristics, isothermal adsorption heat, van der Waals and Coulomb interactions, gas distribution density, adsorption configuration, and gas radial distribution function were analyzed to identify the intrinsic mechanism of anchoring Li/Na/K to improve CO 2 capture and separation performances. [ABSTRACT FROM AUTHOR]

Natural rubber is a key agro-industrial product in Asia, Africa, America, and Oceania, with widespread applications (e.g. tires, latex gloves, wet suits). The energy consumption of the traditional rubber drying process is very high and improvements should be investigated to both reduce the energy consumption, and reduce the cost of the rubber processing. The research investigated both heat recovery and solar air heating (SAH) to minimize the energy consumption of the drying process. A complete assessment of an industrial rubber drying plant in China demonstrated that a heat recovery can reduce the energy consumption by 16 to 44%. If moreover SAH is applied, further energy savings can be achieved. A pilot-scale SAH was tested. Its solar transfer efficiency was between 30% and 50%. Experimental data were theoretically validated, and used in a scale-up design strategy, resulting in an overall drying energy saving of 60 to 77%. The corresponding total investment and payback period are 300 and 420 k€ and 2 to 3.3 years respectively. The novel layout of the energy-efficient rubber dryer, and its energy performance are illustrated. [Display omitted] • Natural rubber is a key agro-industrial product. • The energy consumption for rubber drying is very high. • Energy savings are achieved by integrated heat recovery. • Solar air heating can further reduce the energy consumption. • A total saving on drying energy of 60 to 77% is achieved. [ABSTRACT FROM AUTHOR]

• The octopus tentacle-like composite coagulant was prepared. • This special structure can improve performance of the coagulant. • Destabilizing O/W emulsified oil droplets. • The treated sewage meets the reinjection standard. The complexity of oily sewage from oilfields has risen with the advancement of polymer flooding technology, thereby increasing the treatment challenge. In this study, a composite coagulant, PVPAM-PPFS, was proposed, inspired by octopus tentacles, with PVP as the backbone. FTIR, 1H NMR and Rg radius of gyration were used to characterize the functional groups and conformation of PVPAM-PPFS in aqueous environments. The composite coagulant exhibits facile dispersion in water. Upon hydrolysis of PVPAM-PPFS, numerous molecular chains resembling octopus tentacles are formed and confirmed through Atomic Force Microscopy (AFM). When applied to oily sewage in oilfields, PVPAM-PPFS demonstrates enhanced interaction with emulsified oil layers, capturing colloidal particles in water and thereby facilitating efficient separation of oil, water, and flocs. Lastly, the mechanism of PVPAM-PPFS was analyzed through a combination of coagulation experiments and detection of floc morphology. PVPAM-PPFS will better interact with colloidal particles in water through increased charge neutralization, bridging adsorption, and sweeping capabilities. Significantly, an enhanced crude oil recovery rate is observed from the recovered oil droplets following the disruption of the emulsion layer. [ABSTRACT FROM AUTHOR]

High operation and maintenance costs, and 'last-mile' issues for populations not connected to municipal water infrastructure, have limited the utility of centralized reverse osmosis (RO) systems to alleviate water availability issues for rural communities. To address these challenges, a decentralized RO module which employs tubular RO membranes was designed and investigated. The system represents an appropriate technology because it requires minimal pretreatment and it fits in self-contained, low-profile suitcase. This compact desgin also incorporated innovative 3D printed static mixers to minimize salt concentration polarization and to improve performance. Since grid electricity may also be discontinuous in the target use cases, the system was tested with two direct current (DC) power solutions: a photovoltaics-battery configuration and an alternator-battery. The final prototype weighs less than 15 kg and was found to have a production capacity of ∼8 L/h, consuming ∼100 W of pumping power. Experiments of the prototype module revealed a 96% rejection rate of salt from a 1000–2000 ppm synthetic groundwater solution and a >99% rejection coefficient for bovine serum albumin protein and humic acid. From these performance metrics, it was estimated that 36 sets of this decentralized system (with a total CapEx of US$23,400) could provide drinking water for ∼600 rural households at a unit cost of water of 1 LKR/L (0.005 USD/L) in Sri Lanka. Overall, this study demonstrates how computational modeling and 3D printing can be leveraged to develop a compact and cost-effective decentralized RO package that could be rapidly deployed to water-stressed rural areas and in disaster relief applications. [Display omitted] • A plug-and-play, compact DC driven mobile RO desalination system was developed. • Both alternator-battery and solar PV- battery power solutions were designed and tested. • The system is less than 15 kg and can produce 8 L/h of water with 100 W of power. • Rejection of 96% for salt and >99% for both protein and humic acid was observed. • The levelized cost of water of water was found to be < 0.005 USD/L. [ABSTRACT FROM AUTHOR]

Tm3+ doped YAlO3 (Tm:YAP) crystals with different concentrations were grown successfully by Czochralski method. The full width at half maximum of 0.007–0.008° shows high crystalline quality. The shape of dislocation etching pit is consistent with its crystal structure. The absorption spectra show an intensive peak located at 794 nm. The fluorescence lifetimes of 6.06, 4.68, 4.22, 4.01, and 1.93 ms decrease monotonically with the increase of Tm3+ concentration in the range of 2–7.5 at%. The fluorescence spectra exhibit two strong peaks appeared near 1775 and 1853 nm, respectively. Among them, the 4 at.% Tm:YAP crystal possesses the largest fluorescence intensity at 1853 nm, indicating that it is a promising gain material operated at ~ 1.9 μm for the development of diode-pumped solid-state lasers and the dopant concentration larger than 4 at.% may cause decline in laser performance owing to larger reabsorption loss and higher nonradiative decay rate. [ABSTRACT FROM AUTHOR]

Background: With the widespread use of broad-spectrum antibiotics, the problem of bacterial resistance has become a global crisis. To monitor bacterial resistance in our hospital, the distribution of specimens, the detection of pathogens and their drug resistance from July 2005 to June 2007 (13 years ago) and July 2018 to June 2020 were compared and analyzed. Methods: Ordinary specimens (such as sputum, urine, feces, and secretion) were inoculated in blood AGAR media, MacConkey medium, chocolate medium, double SS medium and selective culture medium. Blood, cerebrospinal fluid, pleural effusion, joint cavity effusion and other sterile body fluid samples were inoculated in aerobic and anaerobic blood culture flasks. Automatic microbial identification, drug sensitivity analysis and mass spectrometry analysis were used to determine their drug sensitivity. Results: Compared with the results obtained 13 years ago, the number of specimens submitted for inspection in the past two years has increased significantly, exhibiting a growth rate of 283%. The changes in the pathogen species were obvious. Gram-positive cocci were the dominant bacteria 13 years ago, and Gram-negative bacilli were the dominant bacteria in the past two years. In addition, the resistance of several major Gram-negative bacilli to piperacillin/tazobactam, cefoperazone/sulbactam, meropenem and imipenem all showed an increasing trend. Conclusion: The variety of pathogenic bacteria in our hospital has changed significantly in the past two years compared with that 13 years ago, and the clinical isolates of Gram-negative bacilli have increased significantly compared with Gram-positive cocci. In the clinical treatment of anti-infective diseases, antimicrobial agents should be selected according to the bacterial distribution characteristics and drug resistance in each hospital. [ABSTRACT FROM AUTHOR]

The second-order elastic constants, third-order elastic constants, and the generalized-stacking-fault energy for semiconductor GaAs are investigated using the first-principles calculations. The predictions of elastic constants are obtained from the coefficients of the fitted polynomials of the energy-strain functions. It is found that the nonlinear elastic effects must be considered when the applied deformations are larger than approximately 1.5%. With the Lagrangian strains up to 6.4%, the terms included up to third order in energy expansion functions are sufficient. The elastic constants given in this work agree well with the previous results and experimental data except for C144. C144 given by the present paper is a positive value, and the estimated 3 GPa agrees well with the experimental result of 2 GPa. The research results can provide a reference for understanding the elasticity of GaAs. The generalized-stacking-fault energy has been calculated without and with structural relaxation, respectively. The unstable stacking fault energy with structural relaxation is about two-thirds of that without relaxation. The dislocation width and Peierls stress for 30° partial in GaAs have been investigated based on the improved P-N theory. The dislocation width is very narrow (only about one-fifth of Burgers vector b), which is reasonable for covalent materials. The Peierls stress is about 4 GPa, in good agreement with the experimental result of 2∼3 GPa. [ABSTRACT FROM AUTHOR]

Crude oil is one of the most important energy sources in the world and contains a lot of paraffin wax. At higher temperatures, paraffin wax is dissolved in crude oil in an equilibrium state. However, when the temperature is lower than the precipitation temperature of wax, paraffin wax will precipitate, crystallize, and form a three-dimensional network structure, which will have a great impact on the transportation of crude oil. In engineering, waxy crude oil is usually transported by adding pour point depressants. Pour point depressant molecules can significantly improve the crystallization behavior of wax in waxy crude oil. This article reviews the types, preparation methods, and future development prospects of new pour point depressants in recent years. The nucleation mechanism of new NPPD synthesized by different methods and wax crystals in crude oil is summarized and commented. Starting from the microscopic morphology of the wax crystal, a prospect is put forward for the preparation of a new type of high-efficiency NPPD with better performance in the future. [ABSTRACT FROM AUTHOR]

The paper assesses the behavior of cohesive Geldart C-type particles, when fluidized by air with the aid of vibration. Together with their poor flowability and irregular hopper discharge, bubbling fluidization is very difficult to achieve due to the possible particle agglomeration and gas channeling. When trying to fluidize cohesive particles, the gas drag force cannot break the inter-particle bonds. Despite all these handling and operation problems, ultrafine particles of micron- or nanosize are increasingly applied in industrial processes. To disrupt the stable gas channels and cracks, a mechanical vibration is one of the easier and preferred methods to improve the fluidity of the cohesive particles. In the present study, several 2 to 40 μm particles were used. A comparison with Geldart A-type particles was also made. Experimental results were used to validate a more fundamental approach based upon the balance of forces acting on the particles. This resulted in a new delineation of the Geldart C/A boundary where the critical transition particle size for particles of given absolute density, ρ p , Hamaker constant, H , and inter-particle distance, z 0 , decreases with an increasing vibration intensity, I , according to d crit 2 ρ p = 8.03 H z 0 2 1 + I g. Mechanical vibration is a non-intrusive method to improve the fluidity of the cohesive particles and a new Geldart C/A boundary was modified for an increasing vibration intensity. [Display omitted] • Assesses the behavior of cohesive Geldart C-type particles, when fluidized by air with the aid of vibration. • Despite handling and operation problems, ultrafine particles are increasingly applied in industrial processes. • Mechanical vibration is a non-intrusive method to improve the fluidity of the cohesive particles. • Several 2 to 40 μm particles were examined and compared with Geldart A-type particles. • Experimental results and a balance of forces provided a new Geldart C/A boundary for an increasing vibration intensity [ABSTRACT FROM AUTHOR]

• A new method of chemical modification of bamboo was studied. • The green modification of perilladehyde improves the anti-fungal performance and dimensional stability of bamboo. • Chemical components of bamboo such as lignin and hemicellulose can serve as binding sites for perilladehyde. • Revealed the connection between the modification mechanism of perillaldehyde and bamboo properties. Bamboo exhibits potential as a viable substitute for wood; nevertheless, its vulnerability to mold poses a significant obstacle to its practical implementation. To address this issue, prevalent techniques, including heat treatment, chemical modification, and compression treatment, alter the characteristics of bamboo and safeguard it against mold. However, these modifications are limited by substantial energy consumption, elevated expenses, and low sustainability. In light of these challenges, perillaldehyde (PAE) emerges as a natural antimicrobial agent capable of impeding the proliferation of diverse mold strains. In this study, the immobilization of PAE in bamboo was achieved for the first time using diethylenetriamine, forming a Schiff base structure with bamboo components. The modified bamboo exhibited three-fold enhanced surface hydrophobicity, which effectively prevented mold infections. Additionally, the modification process improved the dimensional stability of bamboo, albeit at the expense of a slight reduction in elasticity and hardness. The structural analysis of bamboo by FTIR, XPS, and XRD techniques revealed that lignin and hemicellulose served as potential reactive components of PAE. This study presents a novel approach to bamboo preservation utilizing natural components, thereby enhancing the resistance against mold and improving the physical characteristics of bamboo. [ABSTRACT FROM AUTHOR]

Co2+ and F– are doped into lattice of TiO2 powders, and the effects on charge trapping, recombination, and interface transfer are systematically researched. Double doped TiO2 photocatalyst was introduced on Graphene oxide, to construct heterojunction for photocatalytic denitrification of fuel containing pyridine (PY), indole (IND), and quinoline (QUI). A significant improvement in the photocatalytic activity was detected with the double doped modified heterojunction photocatalyst as compared to the pure TiO2. The reason for the improvement of the photocatalytic denitrification performance of oil may be derived from that the doped metal ions and nonmetal ions capture charge carriers to provide an alternative pathway for interface charge transfer, decreased the band gap width and the energy required for the transition, and caused the red shift in the light response range. On the other hand, catalyst supported on RGO, not only accelerated the transfer of photogenic carriers, improved the life of catalytic active component, but also enhanced the dispersibility of catalyst in oil. The experimental results showed that the activity and reusability of the photocatalyst denitrification performance was found satisfactory. On this basis, it is indicated that Co2+/F–/TiO2-RGO can be prospective materials for catalytic denitrification of oil. [ABSTRACT FROM AUTHOR]

Heterojunction photocatalysts have important applications in many fields due to their enhancement of photogenic carrier transfer and broadening of light response range, however, most of them were prone to agglomeration that resulting in reduced efficiency. Therefore, we modified BiVO4-TiO2 heterogeneous photocatalyst by RGO in the hope to improve their dispersion. Since the RGO has a large specific surface area and has many functional groups, it can be combined with BiVO4-TiO2, which not only provides electron transfer channels, enhances electron-hole pair separation power, reduces the loss of composite, but also reduces the interface energy, improves the dispersion of the catalyst in the oil and increases the contact area with the nitride to promote the denitrification rate. In this paper, the physicochemical properties, dispersibility and denitrification performance of photocatalyst were systematically explored. This study may provide a simple and green method for deep processing, safe storage and transportation of oil products. [ABSTRACT FROM AUTHOR]

A multiple-objective optimization method has been suggested for a combined cooling, heating, and power (CCHP) system in this study. The combined CHP system includes a heat-recovery system, a humidifier, a gas compressor, and a small size absorption chiller along with a 5-kilowatts Proton Exchange Membrane (PEM) Fuel Cell stack. An enhanced version of Farmland Fertility Optimizer has been suggested for developing the system efficiency concerning economics, environment, and thermodynamics. For system efficiency validation, it has been analyzed in terms of exergy and energy effectiveness, pollutant emission decline, and yearly expense and a comparison of the results with NSGA-II from the literature, and the basic FFO algorithm is carried out. The results show that the maximum value for the exergy efficiency and the annual GHG reduction is 48.08% and 5.45e7 g, respectively. Also, the annual cost has been decreased to 28.30e3 $. Simulation results show 35.12% energy effectiveness which is better than the compared methods. [ABSTRACT FROM AUTHOR]

In this paper, we study the immersed finite element (IFE) method for the multi-layer porous wall model for the drug-eluting stents. Firstly, under some realistic assumptions on the initial data and the body force, we deduce the long time p r i o r i stability for the variational problem for all t ∈ R +. Then, based on these results, the uniform optimal error estimates for both the semi-discrete IFE method and the fully discrete Euler IFE method are proved. Finally, some numerical experiments are performed to verify the theoretical predictions. [ABSTRACT FROM AUTHOR]

The application of lipophilic composite nanoparticle photocatalysts to denitrification is an important issue, because the lipophilic catalyst exhibits excellent performance compared to other photocatalysis. Taking inspiration from the super-hydrophobic self-cleaning ability of lotus leaf, we reported here that BiVO4–TiO2-570/sepiolite nanosheet composites were prepared by a facile hydrothermal method. The photo-generated carriers in the heterojunction can be separated efficiently and rapidly under the electric field formed in the space charge region to enhance the catalytic activity and lifetime. In this paper, we organically modified the catalyst by adding silane coupling agent (KH-570), which not only reduces the specific surface energy of the catalyst, but also realizes the lipophilicity by constructing the micro-nano structure, so that it is uniformly dispersed in the oil. Meanwhile, using inexpensive nano-sepiolite as a carrier to provide an electron transport medium, accelerate hole-electron separation and increase specific surface area. The catalytic performance of the lipophilic composite nanoparticles was demonstrated by the photocatalytic degradation rate of pyridine contained in simulation oil. The experiment results shows that modified super-lipophilic nanoparticles was obviously higher than that of pure TiO2, which might provide a simple and environmentally friendly approach for the photocatalytic degradation of oil nitrides. [ABSTRACT FROM AUTHOR]

• Salicylic acid (SA) treatment suppressed the pericarp browning of harvested longans. • SA treatment retained higher levels of pericarp pigments in harvested longans. • SA treatment lowered cell membrane permeability in the pericarp of harvested longans. • SA treatment increased ROS scavenging capacity in the pericarp of harvested longans. • SA treatment reduced membrane lipid peroxidation in the pericarp of harvested longans. Longans is popular among consumers because of its rich nutritional value, but it is prone to pericarp browning as it is harvested in the high-temperature season. This work was to investigate the effects of salicylic acid (SA) on the metabolisms of reactive oxygen species (ROS) and membrane lipid and their relationship with pericarp browning of postharvest longans. 'Fuyan' longans were soaked in the solution of 0.3 g L-1 SA for 5 min, then stockpiled at 28 °C. The results showed that, the pericarp browning index in SA-treated fruit was 42% lower than that in the control fruit at day 5 of storage. Meanwhile, SA treatment reduced the damage severity of cell membrane structure, and maintained a low level of cell membrane permeability, which was 25% lower than that in the control fruit at day 5 of storage. Additionally, compared to the control fruit, SA-treated longans displayed higher levels of pericarp L* , flavonoid, chlorophyll, carotenoid, total phenolics, and anthocyanin, higher activities of pericarp superoxide dismutase, catalase, and ascorbate peroxidase, higher values of pericarp reducing power and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, and higher amounts of pericarp ascorbic acid and glutathione, but lower levels of pericarp ROS and malondialdehyde. Moreover, SA-treated samples exhibited lower activities of pericarp phospholipase, lipase, and lipoxygenase, lower levels of pericarp phosphatidic acid and saturated fatty acids (SFA), but higher values of pericarp phosphatidylcholine, phosphatidylinositol, and unsaturated fatty acids (USFA), higher index of USFA, and higher ratio of USFA to SFA. These findings corroborated that SA delayed-browning occurrence in the pericarp of fresh longans was because SA enhanced the capacity to remove ROS, and reduced ROS accumulation and the membrane lipid degradation, thus maintaining the cellular membrane structure, reducing the degradation of pigments, and allowing the fresh longans to maintain a better appearance. Consequently, SA could be an effective means for suppressing pericarp browning and improving the commercial value of fresh longans. [ABSTRACT FROM AUTHOR]

In this study, a simple hydrothermal synthesis method was adapted for the preparation of Co-doping Co2+/F-/TiO2 nanotubes photocatalyst, and the micro-nano structure of catalysts prepared by biomimetic technology which makes the catalyst have super-oleophilicity property. Co2+/F-/TiO2 revealed improved photocatalytic performance for denitrification of light oil compared to single TiO2 photocatalysts. The enhance of photocatalytic activity can be attributed to narrowing the band gap, increasing the light response wavelength and exposing more highly active crystal surfaces due to synergistic effects of Co2+ and F− in the photocatalyst. [ABSTRACT FROM AUTHOR]

Highlights • High quality Cr,Er:YAG crystal was grown successfully by the Czochralski method. • Maximum single-pulse energies of 0.99 and 1.52 J are obtained on Er:YAG and Cr,Er:YAG. • Slope efficiencies are 1.31% and 1.80% for Er:YAG and Cr,Er:YAG, respectively. • Cr3+ can improve laser efficiency of Cr,Er:YAG without affecting beam quality. • Cr,Er:YAG may be a potentially mid-infrared radiation-resistant laser material. Abstract We demonstrated an improvement of laser performance by co-doping Cr3+ into Er:YAG crystal grown by the Czochralski method. The result of X-ray rocking curve suggested that the crystal had high crystalline quality. Two strong absorption bands centered at 450 and 596 nm indicated the Cr,Er:YAG crystal was more suitable for xenon lamp pumping. A maximum single pulse energy of 1.52 J was obtained on the Cr,Er:YAG crystal operated at 5 Hz and 2.94 μm, corresponding to the slope efficiency and electrical-to-optical efficiency of 1.80% and 1.28%, but those of the Er:YAG crystal were only 0.99 J, 1.31% and 0.83%, respectively. Therefore, the Cr,Er:YAG crystal may be a potentially mid-infrared radiation-resistant laser material with higher single pulse energy and efficiency. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • 5-HMF can be converted to DFF by a green photocatalytic selective oxidation process. • 10.5% WO 3 /g-C 3 N 4 composite catalyst exhibits good performance under visible light. • A high DFF selectivity of 87.2% can be achieved under visible light. • The catalytic process follows a Z-scheme mechanism. Abstract WO 3 /g-C 3 N 4 (graphitic carbon nitride) composite was prepared via a directly calcination method with ammonium tungstate hydrate and melamine as raw materials, and applied in the photocatalytic oxidation of 5-hydroxymethylfurfural (5-HMF) to 2,5-diformylfuran (DFF) for the first time. Its physicochemical properties were characterized by HR(TEM), XRD, FT-IR, XP, UV-vis, PL, PC and EIS methods. The results revealed that the doping of WO 3 into g-C 3 N 4 can reduce the possibility of charge recombination and thus enhancing the photocatalytic activity. The impact factor, such as incident wavelength, reaction time, and solvent were also studied on the photocatalytic behavior. 4.7%WO 3 /g-C 3 N 4 composite catalyst exhibits the highest 5-HMF conversion of 27.4% with DFF selectivity of 87.2% under the irradiation of visible-light (>400 nm). As the active species, O 2 − and h+ plays an important role to convert 5-HMF to DFF. Finally, the Z-scheme mechanism and reaction route were proposed by combining the photocatalytic performance with the active oxygen species research of the WO 3 /g-C 3 N 4 catalyst. [ABSTRACT FROM AUTHOR]

Catheter-based left atrial appendage closure (LAAC) has recently become an innovative strategy for preventing embolic events in patients with nonvalvular atrial fibrillation (AF). There is limited information on optimal sizing for LAAC with the recently developed LACBES® device. The aim of the present study was to assess the role of real time-three dimensional transesophageal echocardiography (RT-3D TEE) for LACBES® device selection during LAAC. A total of 22 patients with nonvalvular AF and indications for LAAC were enrolled in the study. All patients underwent LAAC with LACBES® devices. TEE was performed in all patients 3 days prior to the procedure, during the procedure, and 3 months and 1 year following the procedure. Interatrial septal puncture, exchange of the sheath and release of the device were performed under the guidance of RT-3D TEE. The LAA ostium and landing zone dimensions measured by RT-3D TEE were better correlated with the device size used for occlusion (r=0.60, P=0.003) than those measured with two dimensional TEE or LAA contrast angiography. There were no clinically significant residual shunts, pericardial effusion or tamponade following occlusion. All patients had the device well-seated and presented no evidence of closure-associated complications during the follow-up. No cases of peri-procedural stroke or mortality were observed during a mean follow-up period of 12 months. In conclusion, RT-3D TEE is a reliable and effective imaging modality to guide LAAC using LACBES® devices in patients with nonvalvular AF at high risk of cardioembolic events. [ABSTRACT FROM AUTHOR]

Steam flooding is an effective development method for heavy oil reservoirs, and the steam flooding assisted by the profile control system can plug the dominant channels and further improve the recovery factor. High-temperature-resistant foam as a profile control system is a hot research topic, and the key lies in the optimal design of the foam system. In this paper, lignin was modified by sulfonation to obtain a high-temperature-resistant modified lignin named CRF; the foaming agent CX-5 was confirmed to have good high-temperature foaming ability by reducing the surface tension; the formula of the profile control system (A compound system of CRF and CX-5, abbreviated as PCS) and the best application parameters were optimized by the foam resistance factor. Finally, the effect of PCS-assisted steam flooding in enhanced oil recovery was evaluated by single sand packing tube flooding, three parallel tube flooding, and large-scale sand packing model flooding experiments. The results show that CX-5 has a good high-temperature foaming performance; the foam volume can reach more than 180 mL at 300 °C, and the half-life is more than 300 s. The optimal PCS formulation is 0.3 wt% CRF as an oil displacement agent + 0.5 wt% CX-5 as a foaming agent. The optimal gas–liquid ratio range is 1:2 to 2:1, and the high pressure and permeability are more conducive to the generation and stability of the foam. Compared with steam flooding, PCS-assisted steam flooding can improve oil recovery by 9% and 7.9% at 200 °C and 270 °C, respectively. PCS can effectively improve the heterogeneity of the reservoir, and increase the oil recovery of the three-parallel tube flooding experiment by 28.7%. Finally, the displacement results of the sand-packing model with large dimensions show that PCS can also expand the swept volume of the homogeneous model, but the effect is 9.46% worse than that of the heterogeneous model. [ABSTRACT FROM AUTHOR]

An Er:Y3Ga5O12 crystal doped with 30 at% Er3+ was grown by the Czochralski method. The crystal structure and component, thermal and spectroscopic properties are studied systematically. The laser performance of a Φ 3 mm × 66 mm Er:YGG crystal was investigated with LD side-pumped method in the CW mode. The maximum output power of 7.25 W is much higher than that has been realized in the LD end-pumped Er:YGG crystal. The results indicate that the Er:YGG crystal is an ideal material to realize 3 μm laser and the LD side-pumping is a preferred approach to achieve high-power CW laser. [ABSTRACT FROM AUTHOR]

A new Cr 3+ , Yb 3+ , Ho 3+ , and Pr 3+ co-doped GYSGG (Gd 2 YSc 2 Ga 3 O 12 ) single crystal with a size of Φ 26 mm × 80 mm was grown successfully using the Czochralski method for the first time. Absorption spectrum is studied, and main absorption bands are centered at 449, 638, and 934 nm. The fluorescence spectrum shows a broad emission band around 2.8 µm, indicating the Cr 3+ and Yb 3+ ions can act as the sensitizer for the Ho 3+ ions. The fluorescence lifetimes of the 5 I 6 and 5 I 7 levels of the Ho 3+ ions are fitted to be 0.39 and 5.31 ms, respectively. By comparison with those of the Cr,Yb,Ho:GYSGG crystal, the Pr 3+ ions acting as the deactivator can decrease efficiently the lifetime of the lower laser level 5 I 7 of the Ho 3+ ions. Additionally, a flash lamp pumping 2.84 µm laser with maximum average power of 257 mW is achieved. These results indicate the Cr,Yb,Ho,Pr:GYSGG crystal is a new promising radiation-resistant laser gain medium applied in radiant environment. [ABSTRACT FROM AUTHOR]

Particle suspensions can be used in Solar Power Towers to capture the solar heat at a high temperature, and convey it to the storage and the subsequent use in the power block. Thermal Energy Storage (TES) needs to be integrated. Temperatures of 600–900 °C foster the use of high-efficiency power generation cycles. Appropriate Phase Change Materials (PCMs) in that temperature range were examined, i.e. Sb 2 O 3 for the lower melting point range, and BaCO 3 and its Na 2 CO 3 compounds as high melting PCMs. Cooling rates of the melt and solid phases follow a linear-time relationship. The time for solidification of the melt is also measured. Rates and times are compared with the theoretical approaches of unsteady state conduction and phase transition. The cooling rate of the melt is significantly higher than the cooling rate of the solid phase. The time of phase transition is a function of the latent heat. Natural convection within the melt enhances the heat transfer, and is predicted by assigning an effective thermal conductivity to the melt. The thermal cycling of the encapsulated PCMs demonstrates that the selected encapsulation material retains its mechanical properties for 1250 charge/discharge cycles. Practical considerations on TES design conclude the research. [ABSTRACT FROM AUTHOR]

Solar thermal electricity generated by concentrated solar power (CSP) plants is increasingly implemented. CSP plants can supply electricity on a fully matched supply-demand basis if equipped with a thermal energy storage. To increase the efficiency and reduce both capital and operating costs, a next generation of CSP concepts is required. Particle suspensions can be applied to meet these targets and can be used throughout the CSP conversion process, as high temperature heat transfer medium in the receiver, for heat storage, and in the power block of the plant. This work presents the novel concept of using particle suspensions as heat carriers, mostly further to initial testing at the CNRS 1 MW solar furnace of Odeillo Font-Romeu (F). Values of the heat transfer coefficient up to 1100 W/m 2 K (bare tubes) and 2200 W/m 2 K (finned tubes) were obtained for operation at low superficial gas velocities of 0.04–0.19 m/s, thus limiting heat losses by the exhaust air. Despite additional costs for particle handling and for an appropriate boiler, the required overall investment and operating costs are expected to be significantly lower than for common equivalent molten salt CSPs, leading to a reduction in Levelized Cost of Electricity (LCOE) from approximately 125 €/MWh to below 100 €/MWh. [ABSTRACT FROM AUTHOR]

• Laser performance of LD side-pumped Er:LuYSGG bonding crystal was demonstrated. • Maximum output power of 20.76 W is achieved and improved effectively by bonding. • M 2 factors of 6.80/6.74 of the bonding crystal are better than that of un-bonding one. • Er:LuYSGG bonding crystal is a promising 2.8 μm gain element operated at high power. We demonstrate the laser performance of 970 nm LD side-pumped LuYSGG/Er:LuYSGG/LuYSGG bonding crystal in a frequency range of 50–800 Hz. The thermal distribution simulation implies that the bonded Er:LuYSGG crystal possesses a higher cooling efficiency compared with the un-bonded one. The maximum average power of 20.76 W is realized at a frequency of 150 Hz and a pulse width of 200 μs, corresponding to a slope efficiency of 23.94 % and optical-to-optical conversion efficiency of 19.22 %. A single laser wavelength of 2797.5 nm is observed. The M 2 factors of the bonding rod are 6.80/6.74, indicating a relatively high beam quality. Therefore, the LuYSGG/Er:LuYSGG/LuYSGG bonding crystal exhibits an improvement of laser performance operated at 2.8 μm due to excellent heat dissipation ability, which is a promising gain element and can be applied to the harsh radiation environment. [ABSTRACT FROM AUTHOR]

Bamboo's long-acting mold resistance is essential to its durability and applications. Cinnamaldehyde can be used to protect bamboo against microorganisms, but bonding linkages are easily broken, resulting in poor anti-mold performance. In this study, for the first time, cinnamaldehyde was successfully introduced into bamboo constituents via an in-situ Mannich reaction. As a result of the modification, stronger anti-mold resistance was observed for bamboo with a cinnamaldehyde Schiff base structure. The increased surface hydrophobicity of modified bamboo caused by various levels of cinnamaldehyde fixation effectively negated mold affection. Multiple approaches were used to identify bamboo lignin and xylan as cinnamaldehyde binding sites, revealing the underlying mechanisms of reaction. This study provides new insight into green chemistry-based strategies for bamboo preservation under Mannich reactions, in addition to demonstrating a reliable pathway to improve the mold resistance of bamboo. [Display omitted] • A novel approach to improving bamboo's mold resistance was developed. • Lignin and hemicellulose were identified as the targeted biopolymers. • The mechanisms behind bamboo's linkages and changes in morphology were shown. [ABSTRACT FROM AUTHOR]

In this work, different synthetic methods of polymeric aluminum silicate sulfate (PASS) and their coagulability to oily sewage were comparatively studied. PASS was synthesized by two methods: gravity supercritical method and basic titration method, denoted as PASS-B and PASS-S, respectively. The results show that the PASS prepared by gravity supercritical method has better Alb and stability. By applying two coagulants to oily sewage, it was found that PASS-B exhibited better turbidity and oil removal. It was found that PASS-B still has good coagulation by testing its coagulation after placing the coagulant for 2 months. In acidic test water, PASS-B exhibited stronger deprotonation ability. Finally, the polymerization mechanism and coagulation mechanism of PASS-B were analyzed in combination with Al morphology distribution and coagulation experiments. Gravity supercritical method as a new polymerization method may replace the traditional preparation method of inorganic polymer coagulants in the future, especially in large-scale applications. [Display omitted] • Gravity supercritical method can reduce PASS preparation time. • Gravity supercritical method can improve the stability and the Alb of the PASS. • This method may replace traditional polyaluminum preparation process in the future. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the laser performance of LD end-pumped LuYSGG/Er:LuYSGG composite crystal. Thermal distribution simulations by varying the pump spot size indicate that the suitable pump power density is a key factor affecting the laser performance, which is consistent with the experimental result. The maximum output power and slope efficiency achieved were 1266 mW and 24.3% in CW mode, which increased by 39.3% and 12.5%, respectively, compared with unbonded Er:LuYSGG crystal. The laser wavelength location was at 2797.6 nm, and the power fluctuation was about 5.1%. Moreover, the beam quality factors Mx2 and My2 improved to 1.33 and 1.42 from 1.78 and 1.83, respectively. The results suggested that an LD end-pumped LuYSGG/Er:LuYSGG composite crystal with a high beam quality can be applied as a seed source in the mid-infrared (MIR) multi-stage amplification laser apparatus. [ABSTRACT FROM AUTHOR]

Background: Recently, deep convolutional neural networks (CNNs) have been widely adopted for ultrasound sequence tracking and shown to perform satisfactorily. However, existing trackers ignore the rich temporal contexts that exists between consecutive frames, making it difficult for these trackers to perceive information about the motion of the target. Purpose: In this paper, we propose a sophisticated method to fully utilize temporal contexts for ultrasound sequences tracking with information bottleneck. This method determines the temporal contexts between consecutive frames to perform both feature extraction and similarity graph refinement, and information bottleneck is integrated into the feature refinement process. Methods: The proposed tracker combined three models. First, online temporal adaptive convolutional neural network (TAdaCNN) is proposed to focus on feature extraction and enhance spatial features using temporal information. Second, information bottleneck (IB) is incorporated to achieve more accurate target tracking by maximally limiting the amount of information in the network and discarding irrelevant information. Finally, we propose temporal adaptive transformer (TA‐Trans) that efficiently encodes temporal knowledge by decoding it for similarity graph refinement. The tracker was trained on 2015 MICCAI Challenge on Liver Ultrasound Tracking (CLUST) dataset to evaluate the performance of the proposed method by calculating the tracking error (TE) between the predicted landmarks and the ground truth landmarks for each frame. The experimental results are compared with 13 state‐of‐the‐art methods, and ablation studies are conducted. Results: On CLUST 2015 dataset, our proposed model achieves a mean TE of 0.81 ± 0.74 mm and a maximum TE of 1.93 mm for 85 point‐landmarks across 39 ultrasound sequences in the 2D sequences. Tracking speed ranged from 41 to 63 frames per second (fps). Conclusions: This study demonstrates a new integrated workflow for ultrasound sequences motion tracking. The results show that the model has excellent accuracy and robustness. Reliable and accurate motion estimation is provided for applications requiring real‐time motion estimation in the context of ultrasound‐guided radiation therapy. [ABSTRACT FROM AUTHOR]

A new laser crystal from Lu2.4Y0.6Al5O12 (LuYAG) co-doped with Cr3+, Tm3+, Ho3+, and Pr3+ ions was grown successfully by the Czochralski method for the first time. The structure parameters of the Cr,Tm,Ho,Pr:LuYAG crystal are determined by the X-ray Rietveld refinement method. The main absorption bands are observed near 426 and 782 nm, and the fluorescence spectrum excited by a 450 nm or 783 nm LD presents an emission band near 2.911 μm, indicating that the co-doped Cr3+ and Tm3+ ions can be utilized as sensitizers for the Ho3+ ions. The lifetimes of the 5I6 and 5I7 levels of the Ho3+ ions were measured and fitted to be 0.070 ms and 1.852 ms, respectively. The energy transfer efficiencies of the processes 5I6 (Ho3+) →3F3,4 (Pr3+) and 5I7 (Ho3+) →3F2 (Pr3+) + 3H6 (Pr3+) were calculated, showing that the Pr3+ ions can play the role of a deactivator for the Ho3+ ions. Furthermore, the energy transfer mechanisms among the Cr3+, Tm3+, Ho3+, and Pr3+ ions were studied. The results suggest that the Cr,Tm,Ho,Pr:LuYAG crystal is a new promising laser medium operating at around 2.9 μm under flash lamp or 783 nm LD pumping. [ABSTRACT FROM AUTHOR]

• Hydrophobically associated PASSi-C16 was successfully prepared. • PASSi-C16 has a similar structure to the emulsion layer. • PASSi-C16 can better interact with the emulsion layer. • PASSi-C16 composite needs for large-scale applications. When the amount of anionic polyacrylamide (APAM) and petroleum sulphonate in polymer-flooding oily sewage increases, a stable emulsification system forms. This makes the treatment of oily sewage increasingly difficult. To better develop high-efficiency coagulants from scratch, this study first determined the structure and carbon number of petroleum sulphonate using 1H NMR and 13C NMR spectroscopy. Then, hydrophobic monomers with different chain lengths were copolymerised with aluminium salts to prepare inorganic polymer coagulants with different hydrophobic association abilities. Three novel coagulants were successfully prepared, as verified by FTIR and hydrodynamic radius detection, and their coagulation mechanism and performance in oily sewage were investigated and compared with (polyaluminium silicate sulphate) PASSi. The particle size and morphology of flocs after the addition of coagulant were detected by laser particle size analysis and scanning electron microscopy. The structure-activity relationship between emulsifiers and coagulants with different chain lengths was studied via the second virial coefficient A 2. Polyaluminium silicate sulphate-hexadecyltrimethoxy (PASSi-C16) was determined to have the best coagulation effect by turbidity, oil removal rate and Zeta potential detection. This may have been due to PASSi-C16 containing a similar lipophilic group to the carbon chain structure of petroleum sulphonate, which could easily destroy the emulsion layer. These results provide insights into methods to improve the hydrophobic association capacity and for the targeted use of associative coagulants in large-scale applications. [ABSTRACT FROM AUTHOR]