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Annealing has been widely recognized as a crucial approach to modify the microstructure and enhance the coercivity of Nd–Fe–B magnets. However, in the context of Nd–Y–Ce–Fe–B magnets with multiple rare earths (REs) exhibiting different diffusion behaviors, annealing effects on the magnetic properties become more complicated and remain unknown. In present work, through a comparative study between as-sintered and annealed Nd–Y–Ce–Fe–B magnet upon 50 wt% Y–Ce co-substitution of total REs, we found that annealing process surprisingly enhances the remanence from 1.17 to 1.20 T, with simultaneous coercivity increment from 612.9 to 660.7 kA·m−1, resulting in drastically improved maximum energy product from 242.0 to 263.5 kJ·m−3. Such a peculiar remanence enhancement is closely correlated to the preferential Y/Nd infiltration into RE2Fe14B main phase and Ce segregation into REFe2 intergranular phase, which consequently improve the intrinsic magnetism, as evaluated by Curie temperature (TC), saturation magnetic polarization (JS) and magnetocrystalline anisotropy field (HA). Present work delights that different metallurgical behaviors of Nd/Y/Ce exert influential effects on the intrinsic and extrinsic magnetic properties and provide a novel approach toward high-performance 2:14:1-type permanent magnets based on abundant RE mixtures.

ChCl-MEA DES was used to absorb CO2 from gasification syngas consisting of CO2, CO, CH4, and H2. This study investigated the effect of water addition on CO2 absorption capabilities of ChCl-MEA DES with different mole ratios of ChCl to MEA, and different absorption temperatures. It was found that water addition had a positive effect on CO2 solubility of ChCl-MEA DES, with the maximum obtained value of 0.5 mol-CO2/mol-DES for aqueous ChCl-MEA DES with 75%vol water at absorption temperature of 40 °C and pressure of 9 bar. In general, water addition increases CO2 solubility and absorption rate of ChCl-MEA DES. ChCl-MEA DES 1:5 mol ratio was able to benefit from water addition up to 75%vol water content. While ChCl-MEA 1:10 had its CO2 solubility increase with water addition up to 50%vol, after which, it declined. Investigation into water addition at different absorption temperatures revealed that water addition at 40 °C produced the most significant CO2 solubility enhancement compared to water addition at 20 °C and 60 °C. This might be caused by the tradeoff between the effects of high temperature in decreasing ChCl-MEA DES viscosity and lowering its CO2 solubility. Highest CO2/CO selectivity for ChCl-MEA DES 1:5 was found to be around 34.6, CO2/CH4 was 26.7, and CO2/H2 was 4. Water addition was found to have slight reducing effect on the CO2 selectivity of ChCl-MEA DES.

Background Depression is the most common mental disorder in patients with advanced cancer, which may lead to poor prognosis and low survival rate. This study aims to explore the serial multiple mediating roles of social support and spiritual coping between hope and depression among patients with advanced cancer. Methods A cross-sectional study was conducted in China between May and August 2020. A total of 442 advanced cancer patients were investigated by the following self-reported questionnaires: Herth Hope Index (HHI), Spiritual Coping Questionnaire (SCQ, Chinese version), Social Support Rating Scale (SSRS), Hospital Anxiety and Depression Scale (HADS). Results Depression was negatively correlated with hope, social support, and positive spiritual coping (P P Conclusions This study proves the hypothesis that social support and spiritual coping play intermediary roles between hope and depression. Interventions established through hope, social support and spiritual coping can effectively prevent depression from occurring.

RDF made of municipal solid waste was pyrolyzed under simulated pyrolytic gas (PG) atmosphere and N2 atmosphere. Besides pyrolysis temperature, the atmosphere also affected the yield of three phase products and thermal conversion. By comparison of the products from two different atmospheres at same pyrolysis temperature, more tar, less char and gas were produced under PG atmosphere than the yields produced under N2 atmosphere; LHV of char produced under PG atmosphere was always lower than the value of char produced under N2 atmosphere, so that the char thermal conversion (CTC) efficiency under PG atmosphere also was lower; O/C and H/C of chars produced PG atmosphere were usually smaller than the data of char produced under N2 atmosphere, which indicated chars produced under PG atmosphere were more similar with coal, and more suitable for co-combustion of coal and char in coal power plant. In additional, highest comprehensive combustion characteristic index S was obtained at 600 °C under PG atmosphere. LHV of gas produced under PG atmosphere was always higher than the gas produced under N2 atmosphere, but gas thermal conversion (GTC) efficiency under PG atmosphere was lower because of less gas yield.

Multi-camera target tracking is a research hot spot in the field of computer vision. Because the field of view covered by the fixed monocular camera is limited, it cannot continuously track fast-moving targets for a long time, such as the video sequence of skaters’ short-track speed skating. However, for such video sequences, the relative displacement of target between frames is relatively large and the advanced tracking algorithm is difficult to achieve accurate tracking, which has a considerable impact on the subsequent target handover. In view of this situation, we use four fixed cameras to build a tracking system to continuously track skater and propose to use convolutional neural network to extract the semantic features of the target to improve the accuracy of the target handover process. Aiming at this kind of fast motion video sequence with a fixed field of view, a new tracking algorithm was proposed. We establish the motion model of the target and integrate the speed information of the target into the sample generation mechanism. In addition, we also construct a scale filter in context to constantly and iteratively update the scale change information of the prediction box to adapt to the significant change of the visual properties of the target. It improves the stability and robustness of the system. Extensive experimental results in object tracking benchmark and our dataset of skaters illustrate outstanding performance of our method compared with the state-of-the-art methods, especially against the fast motion sequences with a fixed field of view.

Proxy reconstructions from marine sediment cores indicate peak temperatures in the first half of the last and current interglacial periods (the thermal maxima of the Holocene epoch, 10,000 to 6,000 years ago, and the last interglacial period, 128,000 to 123,000 years ago) that arguably exceed modern warmth1–3. By contrast, climate models simulate monotonic warming throughout both periods4–7. This substantial model–data discrepancy undermines confidence in both proxy reconstructions and climate models, and inhibits a mechanistic understanding of recent climate change. Here we show that previous global reconstructions of temperature in the Holocene1–3 and the last interglacial period8 reflect the evolution of seasonal, rather than annual, temperatures and we develop a method of transforming them to mean annual temperatures. We further demonstrate that global mean annual sea surface temperatures have been steadily increasing since the start of the Holocene (about 12,000 years ago), first in response to retreating ice sheets (12 to 6.5 thousand years ago), and then as a result of rising greenhouse gas concentrations (0.25 ± 0.21 degrees Celsius over the past 6,500 years or so). However, mean annual temperatures during the last interglacial period were stable and warmer than estimates of temperatures during the Holocene, and we attribute this to the near-constant greenhouse gas levels and the reduced extent of ice sheets. We therefore argue that the climate of the Holocene differed from that of the last interglacial period in two ways: first, larger remnant glacial ice sheets acted to cool the early Holocene, and second, rising greenhouse gas levels in the late Holocene warmed the planet. Furthermore, our reconstructions demonstrate that the modern global temperature has exceeded annual levels over the past 12,000 years and probably approaches the warmth of the last interglacial period (128,000 to 115,000 years ago). Reanalysis of Holocene sea surface temperature records affirms the role of retreating ice and rising greenhouse gases in driving a steady increase in global temperatures over the past 12,000 years.

The influences of minor Y addition on the thermal stability, crystallization behavior, magnetic property and bending ductility of Fe–Si–B amorphous ribbons have been systematically investigated. The results show that all the ribbons with Y addition are fully amorphous structure, and the introduction of Y can enhance the glass forming ability of Fe–Si–B amorphous alloy. With Y addition, crystallization temperature of the first and second phase shift to high temperature side, the temperature interval between the two crystallization peaks are enlarged, the third phase transitions process of Fe–Si–B amorphous alloy with Y addition corresponds to the precipitation of Fe3B phase. The activation energy of the first and second phase calculated by Kissinger’s formula increased with Y addition. Appropriate Y addition is beneficial for Ms. The measured coercivity Hc gradually decreased with the Y addition increased. The amorphous alloys exhibit good bending ductility in the quenched state. The ductile to brittle temperature increase to 300 °C with 1 at% Y addition. Furthermore, the mechanism of ductile to brittle for amorphous alloy was discussed.

Parabolic trough collector is the most mature and widely deployed concentrated solar power technology with temperature ranging from 325 to 700 K. In this study, three different absorber tube geometries (smooth absorber tube, absorber tube with twisted tape insert and tube with longitudinal fins) of commercially available LS-2 collector are modeled and investigated using engineering equation solver. The objective of this study is to present a numerical comparative analysis of the available thermal enhancement techniques. Comprehensive energetic and exergetic performance of different tube geometry configurations using Al2O3/water as a heat transfer fluid has been compared to assess the nature of exergy destruction due to the fluid’s pressure, due to the heat transfer between sun and the receiver wall and due to the temperature difference between receiver wall and heat transfer fluid temperature. Furthermore, pure base fluid (water) along with the nanofluid is used to evaluate the system’s performance (thermal efficiency, exergetic efficiency, heat transfer coefficient, receiver temperature, pressure drop, pumping work demand and friction factor). Smooth absorber tube with pure base fluid is the reference case, while five cases (smooth tube with nanofluid, tube with pure water and fins inserted, tube with nanofluid and fins inserted, tube with pure water and twisted tape inserted, tube with nanofluid and twisted tape inserted) are investigated. Thermal efficiency of absorber tube with twisted tape insert and nanofluid is almost 72.26%, followed by tube with internal fins (72.10%), while smooth absorber tube has nearly 71.09%. Heat transfer coefficient of twisted tape inserted tube with nanofluid and longitudinal fins tube with nanofluid is greater than smooth absorber tube to almost 118.23% and 103.26%, respectively. The emphasis is also given to the pressure drop of the examined cases as it depends up on the friction factor of the absorber tubes. The use of nanofluid and twisted tape inserts leads to higher thermal enhancement, followed by the nanofluid and internal fins inserted tube. The nanoparticle concentration is also varied to investigate its effect on different performance parameters of the system.

Municipal Solid Waste (MSW) was converted into high-grade solid fuels (biochar) and gaseous product via thermal pyrolysis under pyrolytic gas atmosphere. The experiment was carried out in a packed-bed reactor at the temperature range of 600–800 °C in both atmospheres of N2 and pyrolytic gas. Gas, liquid, and solid products were analyzed by gas chromatograph and elemental analysis. Amount of biochar obtained from both atmospheres were not significantly different. CH4 and CO2 in pyrolytic gas promoted the release of volatile in the MSW, resulting in lower ratio of VM/FC, ca. 0.13. The atomic ratios of O/C and H/C were around 0.02–0.11 and 0.005–0.035, respectively. These values were equivalent to anthracite coal type. On the other hand, the liquid fuel yield under pyrolytic gas condition was found to be higher, compared with that under N2 condition. In addition, the enhancement of H2 and CO production was accompanied by the decrease in CH4 and CO2 output. Overall, the operating condition at 800 °C or higher with reaction times longer than 4 min were recommended for production of biochar with fuel qualities approaching anthracite coal.

Highlights A cooperative solvation/surface engineering approach is reported to achieve the reversible Mg plating/stripping in conventional carbonate electrolytes.Benefitting from the strategy, Mg2+ can easily overcome the reduced desolvation barrier and penetrate the Mg2+-conducting polymer coating, deposited on the Mg metal anode successfully, promoting the application of magnesium anode in carbonate electrolytes toward high-energy rechargeable batteries. Supplementary Information The online version contains supplementary material available at 10.1007/s40820-021-00716-1., Magnesium metal anode holds great potentials toward future high energy and safe rechargeable magnesium battery technology due to its divalent redox and dendrite-free nature. Electrolytes based on Lewis acid chemistry enable the reversible Mg plating/stripping, while they fail to match most cathode materials toward high-voltage magnesium batteries. Herein, reversible Mg plating/stripping is achieved in conventional carbonate electrolytes enabled by the cooperative solvation/surface engineering. Strongly electronegative Cl from the MgCl2 additive of electrolyte impairs the Mg…O = C interaction to reduce the Mg2+ desolvation barrier for accelerated redox kinetics, while the Mg2+-conducting polymer coating on the Mg surface ensures the facile Mg2+ migration and the effective isolation of electrolytes. As a result, reversible plating and stripping of Mg is demonstrated with a low overpotential of 0.7 V up to 2000 cycles. Moreover, benefitting from the wide electrochemical window of carbonate electrolytes, high-voltage (> 2.0 V) rechargeable magnesium batteries are achieved through assembling the electrode couple of Mg metal anode and Prussian blue-based cathodes. The present work provides a cooperative engineering strategy to promote the application of magnesium anode in carbonate electrolytes toward high energy rechargeable batteries. Supplementary Information The online version contains supplementary material available at 10.1007/s40820-021-00716-1.

Climate signals associated with 11-year sunspot cycle have been extensively studied in various regions of the northern hemisphere, but the precise mechanisms remain elusive. Asian winter monsoon (AWM) is the most powerful circulation system on the Earth, yet its relationship with the 11-year solar cycle has not been explored. Here the response of AWM to the 11-year solar forcing is explored by analysis of numerical experiment results obtained from the Community Earth System Model-Last Millennium Ensemble (CESM-LME) modeling project. We show that a strong 11-year solar cycle can excite a resonant response of the intrinsic leading mode of the AWM variability, resulting in a significant signal of decadal variation. The leading mode, characterized by a warm Arctic and cold Siberia, responds to the maximum solar irradiance with a peculiar 3 to 4-year delay. We propose a new mechanism to explain this delayed response, in which the 11-year solar cycle affects the AWM via modulating Arctic sea ice variation during the preceding summer. At the peak of the accumulative solar irradiance (i.e., 4 years after the maximum solar irradiance), the Arctic sea ice concentration reaches a minimum over the Barents–Kara Sea region accompanied by an Arctic sea surface warming, which then persists into the following winter, causing Arctic high-pressure extend to the Ural mountain region, which enhances Siberian High and causes a bitter winter over the northern Asia.

The Fe–Si–B amorphous ribbons with various CO ventilation amount were prepared by planar-flow melt spinning method. The effect of CO gas on surface quality, magnetic properties and core loss of amorphous ribbons were investigated. With the increasing CO ventilation, the wheel side surface roughness, average air pocket size and air pocket quality decrease, the ribbon grows thicker, but air side surface roughness remains almost no changes. The three samples have reached to a fully amorphous structure. Meanwhile the diffraction angle corresponding the maximum intensity of each broad diffraction peak decrease slightly with increasing CO ventilation. There is no significant differences in the onset temperate of second exothermic peak (Tx2) and the crystallization peak temperature (Tp1 and Tp2) among the amorphous ribbons prepared with various CO ventilation, but the onset temperate of first exothermic peak (Tx1) increases slightly with the increasing CO ventilation. The room temperature hysteresis loops of amorphous ribbons show that surface quality have significant effect on magnetic properties. The coercivity (Hc), core loss (P1.35/50), magnetic polarization (B80) and permeability (µ) among the ribbons are improved with better surface quality, though the saturation magnetic flux density almost keeps same. Core loss are separated by the scaling theory, and experiment dates show a good agreement with the predicted data. Thus the scaling theory is suitable for Fe–Si–B amorphous alloys. The surface quality has more significant effect on hysteresis losses than eddy current loss at low frequency.

Empty fruit bunch (EFB) is abundantly available for renewable energy resource, especially in Southeast Asian countries. However, EFB has inherent problems such as high moisture content, low heating value, and high alkali metal content. In order to improve the quality of feedstock as a fuel, in this research, the effects of hydrothermal treatment (HT) on the hydrothermally treated EFB (HT-EFB) characteristics were investigated. Also, the pyrolysis characteristics of EFB and HT-EFB were examined. The experiments of hydrothermal treatment were carried out in a 500-mL hydrothermal reactor at the temperature range of 120 to 220 °C with 60 to 120 min holding time. Afterward, the pyrolysis experiments of EFB and hydrothermally treated EFB (HT-EFB) were conducted in a lab-scale isothermal tube furnace at 400 °C for 1 h. The gas product was periodically collected to create gas evolution profiles. The result showed that hydrothermal treatment improved the properties of EFB, such as higher fixed carbon, lower ash content, and higher energy density. Hydrothermal treatment caused an increase in the heating value of HT-EFB to 19.47 MJ/kg, while the ratio of volatile matter/(volatile matter + fixed carbon) decreased from 0.82 to 0.68. Employing hydrothermal treatment in EFB did not only reduce the ash content of the biomass but also reduced the contents of potassium and sodium. In addition, the gas product from HT-EFB pyrolysis resulted in higher content of CO, CH4, and H2. The identified liquid product of pyrolysis consisted of alkane groups, phenolic groups, aromatic groups, ketones, acids, alcohols, and ester, which may be used as liquid fuel or for chemical production after further treatment. The observation indicated that hydrothermal treatment is an appropriate method to improve the fuel characteristic of EFB.

To assess hemodynamic changes related to acute gouty knee arthritis in a rabbit with CT perfusion (CTP) Forty-two rabbits were randomly separated into two groups: the treated group of 30 and the control group of 12. The right knee was injected with monosodium urate solution and polymyxin in the treated group and saline and polymyxin in the control group. At 2, 16, 32, 48, 60, and 72 h after injection, five rabbits from the treated group and two rabbits from the control group were selected for CTP. At each time point, blood flow (BF), blood volume (BV), and clearance rate (CL) were measured, and microvessel density (MVD) was evaluated with a microscope. In the treated group, BF, BV, CL, and MVD were significantly higher than in the control group (p

Single-phase cobalt ferrite nanoparticles were synthesized by coprecipitation method and annealed at different temperatures. The structural, dielectric and magnetic properties were investigated, which showed an obvious dependence on annealing temperature. The average crystallite size increased from 20 to 60 nm with increase of annealing temperature. Meanwhile, the shape of nanoparticles also changed from spherical to octahedron and then cubic. Dielectric constant showed dispersion behavior and decreased with increasing annealing temperature, while the relaxation peaks observed in dielectric loss were shifted to lower frequencies. The ac conductivity originates from Polaron hopping which decreased with increase of crystallite size (less surface area and defect density) due to higher annealing temperature. The saturation magnetization increased from 59 to 81 emu/g and coercivity dropped from 1316 to 428 Oe with the increase of particle size.

The FeSiB amorphous ribbons with monolithic amorphous structure in different free volume state were prepared by annealing the as-cast ribbons at different temperature. The results show that a fairly large amount of free volume for S25 sample, the medium amount of free volume for S250 sample, and the free volume were almost annealed out in S380 sample, and the free volume has great influence on bending behavior and the resultant fracture surface. With the decrease of free volume, the amount of shear bands on the bent crease, bending strain decrease from 1 to 0, critical shear displacement on fracture surface decrease form 3.32 mm decline to ~ 203 nm. Meanwhile, the size of micro-scale vein pattern decreases, the size of nano-scale periodic corrugations increases. The bending strain, shear band density and fracture surface characteristics were discussed via free volume content and shear transform zone size.

3D asymmetric structure could induce asymmetric diffraction with spatial coupling behavior for various optical applications, but the study still faces challenges due to the complicated local-field coupling mechanism within structures. In this study, the spatial asymmetry based on inclined all-dielectric structure was theoretically modeled. The normal reflection of the 2D array shows that the increasing structural inclination selectively enhances the Fano resonance between different polarization directions which is mainly due to the oriented spatial coupling effect by increasing structural asymmetry, proved with the near-field distribution. The angular-resolved reflection shows the selected enhancement of first-order diffraction even over that of zero order by combining the structural asymmetry and oblique incidence. Our study provides a new insight for exploring asymmetric photonic structures and relative devices in practical applications.

In order to enhance the hydrogen storage properties of LiBH4, activated charcoal (AC) was used as the scaffold to confine LiBH4 in this paper. Ball milling was used to prepare LiBH4/AC composites. Experimental results show that dehydrogenation properties of ball-milled LiBH4/AC (LiBH4/AC-BM) are greatly improved compared with that of pristine LiBH4, ball-milled LiBH4 (LiBH4-BM) and hand-milled LiBH4/AC (LiBH4/AC-HM). The onset dehydrogenation temperature of LiBH4 for LiBH4/AC-BM is around 160 °C, which is 170 °C lower than that of pristine LiBH4. At around 400 °C, LiBH4/AC-BM finishes the dehydrogenation with a hydrogen capacity of 13.6 wt%, which is approximately the theoretical dehydrogenation capacity of pure LiBH4 (13.8 wt%), while the dehydrogenation processes for LiBH4-BM and LiBH4/AC-BM do not finish even when they were heated to 600 °C. The isothermal dehydriding measurements show that it takes only 15 min for LiBH4/AC-BM to reach a dehydrogenation capacity of 10.1 wt% at 350 °C, whereas the pristine LiBH4 and the LiBH4/AC-HM release hydrogen less than 1 wt% under the same conditions. The dehydrogenation process and the effect of AC were discussed.

Efforts to improve the performance of hydrothermal treatment (HT) in producing high-quality solid fuel from sewage sludge were carried out by elevating reaction pressure and modifying reaction atmosphere. Reaction pressure was varied by injecting N2 at the initial pressures of 0.1, 1.3, and 3.1 MPa, where the N2 was substituted with air or CO2 to vary the reaction atmosphere. The dewatering performance of the treated sludge, heating value of its derived product, and the efficiency of the treatment process were used as examination criteria. Increasing the initial reaction pressure to 1.3 and 3.1 MPa evidently improved dewatering performance as it produced cakes with 2.4 and 4.4% lower moisture content than the cake produced with normal initial reaction pressure. However, the negative effect on higher heating value (HHV) was also prominent as it produced cakes with the lower HHV of 0.7 and 1.7 MJ/kg. The utilization of CO2 as reaction atmosphere leads to the production of cakes with the higher HHV of 0.3–0.5 MJ/kg than the cakes produced under N2 at the same pressure. Moreover, the application of the initial reaction pressure of 1.3 MPa was found as the prime condition since the treatment effectively produced cake with a high effective heating value with a relatively comparable efficiency to the conventional HT at normal initial pressure.

In order to improve the hydrogen storage properties of LiBH4–MgH2 composite, two different kinds of Nb-based catalysts, NbC and NbF5, were added to LiBH4–MgH2 composite by ball milling, and the effect of catalysts on hydrogen storage properties of the modified LiBH4–MgH2 system was investigated. The experimental results show that LiBH4–MgH2 composite is a two-step dehydrogenation process, and Nb-based compounds can remarkably enhance its dehydrogenation kinetics. For the composite without addition of catalysts, the starting decomposition temperature for the first dehydrogenation step is around 320 °C, and there is a long period of incubation time (around 220 min) for the occurrence of the second decomposition step even at high temperature of 450 °C. It needs more than 10 h to complete the decomposition process and release around 9 wt% H2. After addition of 5 mol% NbF5, the starting decomposition temperature for the first dehydrogenation step is around 150 °C, there is no incubation time for the second decomposition step, and it takes around 40 min to complete the second step and reaches a total dehydrogenation capacity of 9.5 wt%. NbF5 has better catalytic effect than NbC. Based on the hydrogenation/dehydrogenation behaviors and structural variation, the mechanism of catalytic effect was discussed.

A study for producing low moisture content sludge cake was performed by adding NaCl, CaCl2, Ca(OH)2, or FeCl3 to excess sewage sludge under hydrothermal treatment (HT) and varying dewatering conditions from low to high pressure (0.04–12 MPa). FeCl3 addition under HT resulted in cakes with significantly lower moisture content than HT cakes, and moreover, than raw sludge cakes, under all dewatering conditions. The addition of CaCl2 produced similar effects to FeCl3 addition but at weaker extents. The addition of Ca(OH)2 produced much weaker effect than the addition of CaCl2 under the low-pressure dewatering. However, the effects were comparable under the medium- and high-pressure dewatering. The effect of NaCl addition was only prominent under the high-pressure dewatering. Comparison on the moisture content of sludge cakes with the treatments of HT, coagulant-added, and their combination showed that synergy between HT and coagulant addition in producing low moisture content sludge cake was evidenced.