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Herein, a concise, effective, and scalable strategy is reported that the introduction of polar molecules (PMs) (e.g., anisole (PhOMe), phenetole (PhOEt), 2‐methoxynaphthalene (NaphOMe), thioanisole (PhSMe), and N,N‐dimethylaniline (PhNMe2)) as continuously coordinated neutral ligand of cationic active species in situ generated from the constrain‐geometry‐configuration–type rare‐earth metal complexes A–F/AliBu3/[Ph3C][B(C6F5)4] ternary systems can easily switch the regio‐ and stereoselectivity of the polymerization of conjugated dienes (CDs, including 2‐subsituted CDs such as isoprene (IP) and myrcene (MY), 1,2‐disubstituted CD ocimene (OC), and 1‐substituted polar CD 1‐(para‐methoxyphenyl)‐1,3‐butadiene (p‐MOPB)) from poor selectivities to high selectivities (for IP and MY: 3,4‐selectivity up to 99%; for OC: trans‐1,2‐selectivity up to 93% (mm up to 90%); for p‐MOPB: 3,4‐syndioselectivity (3,4‐ up to 99%, rrrr up to 96%)). DFT calculations explain the continuous coordination roles of PMs on the regulation of the regio‐ and stereoselectivity of the polymerization of CDs. In comparison with the traditional strategies, this strategy by adding some common PMs is easier and more convenient, decreasing the synthetic cost and complex operation of new metal catalyst and cocatalyst. Such regio‐ and stereoselective regulation method by using PMs is not reported for the coordination polymerization of olefins catalyzed by rare‐earth metal and early transition metal complexes. [ABSTRACT FROM AUTHOR]

The Pamir, situated in central Asia, is a result of the ongoing northward advance of the Indian continent, leading to compression of the Asian landmass. While geodetic and seismic data typically indicate that the most significant deformation in Pamir is along its northern boundary, an Mw 7.2 earthquake on 7 December 2015 and an Mw 6.8 earthquake on 23 February 2023 have occurred in the remote interior of Pamir. These two Mw ≥ 6.5 earthquakes, with good observations of satellite synthetic aperture radar data, provide a rare opportunity to gain insights into rupture mechanics and deformation patterns in this challenging-to-reach region. Here, we utilize spaceborne synthetic aperture radar data to determine the seismogenic faults and finite slip models for these two earthquakes. Our results reveal that the 2015 earthquake ruptured a ~88 km long, left-lateral strike-slip fault that dips to northwest. The rupture of the 2015 earthquake extended to the ground surface over a length of ~50 km with a maximum slip of ~3.5 m. In contrast, the 2023 earthquake did not rupture the ground surface, with a maximum slip of ~2.2 m estimated at a depth of ~9 km. Notably, the seismogenic fault of the 2015 earthquake does not align with the primary strand of the Sarez–Karakul fault system (SKFS), and the 2023 earthquake occurred on a previously unmapped fault. The well-determined seismogenic faults for the 2015 and 2023 earthquakes, along with the SKFS and other distributed faults in the region, suggest the existence of a wide shear zone extending from south to north within the central Pamir. [ABSTRACT FROM AUTHOR]

The digestion of community solid waste has great development prospects and economic benefits in the context of waste segregation. However, a large amount of biogas slurry is produced in the anaerobic digestion process and needs to be treated. In this study, the digestion performance and optimal recirculation batch in the digestion of community solid waste were investigated when multiple batches of recirculated slurry were mixed with inoculated sludge in the optimal ratio (a sludge volume percentage of 50%) as the inoculum. The results showed that the biogas yield and methane yield per unit load increased gradually with the number of recirculation batches and reached their maximum values in the seventh batch, which were 80.63% (1382.2 mL/g volatile solids) and 51.0% (812.4 mL/g volatile solids) more than the respective initial values. After four cycles of cultivation, the accumulation of volatile fatty acids (VFAs) was significantly alleviated, and the total VFA concentration in the seventh batch was reduced by 49.7% in comparison with the initial value. The digestion process produced methane mainly via hydrogenotrophic methanogenesis and syntrophic acetic acid-oxidizing methanogenesis. The genera Methanobacterium and Methanomassiliicoccus were closely associated with the biogas production performance. These results are helpful to increase the utilization rate of biogas slurry, improve the performance of multiple-batch digestion of community solid waste, and provide relevant biological evidence. [ABSTRACT FROM AUTHOR]

Interferometric Synthetic Aperture Radar (InSAR) enables detailed investigation of surface landslide movements, but it cannot provide information about subsurface structures. In this work, InSAR measurements were integrated with seismic noise in situ measurements to analyse both the surface and subsurface characteristics of a complex slow-moving landslide exhibiting multiple failure surfaces. The landslide body involves a town of around 6000 inhabitants, Villa de la Independencia (Bolivia), where extensive damages to buildings have been observed. To investigate the spatial-temporal characteristics of the landslide motion, Sentinel-1 displacement time series from October 2014 to December 2019 were produced. A new geometric inversion method is proposed to determine the best-fit sliding direction and inclination of the landslide. Our results indicate that the landslide is featured by a compound movement where three different blocks slide. This is further evidenced by seismic noise measurements which identified that the different dynamic characteristics of the three sub-blocks were possibly due to the different properties of shallow and deep slip surfaces. Determination of the slip surface depths allows for estimating the overall landslide volume (9.18 · 107 m3). Furthermore, Sentinel-1 time series show that the landslide movements manifest substantial accelerations in early 2018 and 2019, coinciding with increased precipitations in the late rainy season which are identified as the most likely triggers of the observed accelerations. This study showcases the potential of integrating InSAR and seismic noise techniques to understand the landslide mechanism from ground to subsurface. [ABSTRACT FROM AUTHOR]

Located on the southeastern periphery of the Tibetan Plateau, the Xianshuihe fault (XSHF) is an active left-lateral strike-slip fault renowned for its frequent and intensive seismic activities. This highlights the necessity of employing advanced geodetic methodologies to precisely evaluate the fault kinematics and seismic hazard potential along this fault. Among these techniques, interferometric synthetic aperture radar (InSAR) stands out for its high spatial resolution and regular revisit intervals, enabling accurate mapping of interseismic deformation associated with fault motion. However, the precision of InSAR in measuring deformation encounters several challenges, particularly artifacts stemming from phase unwrapping errors and atmospheric phase delays. In this study, we utilize ascending and descending Sentinel-1 InSAR images spanning from January 2017 to January 2023 to drive the line-of-sight (LOS) mean crustal velocities associated with the XSHF with emphasis on phase unwrapping errors and atmospheric delay corrections. Then, the reliability of the derived LOS velocities is assessed using independent observations from the Global Navigation Satellite System (GNSS). The inferred fault slip rate along the XSHF shows significant along-strike variations, gradually decreasing from ~11.1 mm/yr at the Luhuo section to ~6.6 mm/yr at the Kangding section and then sharply increasing to ~13.0 mm/yr towards its eastern terminus at the Moxi section. The fault locking depth shows similar along-strike variations, decreasing from ~19.5 km in the northwestern part to ~4.8 km at the Kangding section, before increasing to 19.6 km at the Moxi segment. Notably, apparent surface fault creeping, characterized by a slip rate of ~2.7 mm/yr, is observed at the Kangding segment, likely resulting from postseismic slip following the 2014 Mw 6.3 Kangding earthquake. [ABSTRACT FROM AUTHOR]

Considering the fast time varying characteristic of pitch channel model of hypersonic model with coupling of engine, a kind of hybrid attack angle tracking controller is designed based on variable structure and Taylor type FLNN neural network method. And the adoption of variable structure control method make the system response very fast and robust. The Taylor type FLNN neural network is constructed with the format of fitting function which is used to describe the force and moment caused by attack angle, so it can compensate the interruption caused by the uncertainty and unconsidered factors effectively. At last, detailed numerical simulation is done to testify the rightness of the proposed hybrid method. [ABSTRACT FROM AUTHOR]

The mechanism of Fe2+-activated peroxodisulfate (PDS) by hydroxylamine (HA) has been investigated, however, nano zero-valent iron-activated persulfate (nZVI/PDS) has a more optimal effect and needs further investigation. This study investigated the addition of HA to nZVI/PDS to improve Fe2+ regeneration and accelerate methylparaben (MP) degradation by Fe (0/II/III) cycle. After 60 min of reaction, the HA-enhanced nZVI/PDS (HA/nZVI/PDS) system afforded a 21% increase in MP degradation, reaching 93.26% (1 mM HA, 1 mM nZVI, and 2 mM PDS). nZVI/PDS system was a second-order reaction, but after adding HA, the reaction was more suitable for the first-order reaction. The addition of HA effectively promoted the reduction of Fe3+ to Fe2+ to improve the effect and reaction rate of PDS degradation of MP (k increased from 0.0127 min−1 to 0.0198 min−1) and broadened the reaction pH range. The results of various characterizations of nZVI before and after the reaction revealed that nZVI changed from a spherical structure to a bundle structure and was slightly oxidized. Changes in the Fe2+ and Fe3+ concentrations as well as in the pH of the reaction systems were monitored and the possible reactions of the HA/nZVI/PDS system were derived for the first time (k nZVI/PDS <3.7 × 106 M−1 s−1, k Fe3+/NH2O· >4.2 min−1). 12 potential compounds were investigated and MP breakdown pathways were speculated; hydroxylation was determined to be the most important pathway of degradation. And the HA/nZVI/PDS system had universal applicability. [Display omitted] • The addition of HA resulted in a 21% increase in MP degradation, reaching 93.26%. • HA by the dynamic transformation of Fe3+ and Fe2+ to improve the degradation of MP. • SO 4 · − was dominant under acidic condition, ·OH was dominant under alkaline condition. • Most significant cause of MP degradation was hydroxylation. [ABSTRACT FROM AUTHOR]

Methylparaben (MP) is an emerging pollutant, and the optimal conditions and kinetics of MP degradation using nano-zero-valent iron-activated persulfate (nZVI/PDS) need to be further investigated. This paper firstly investigated the response surface methodology (RSM) analysis of MP degradation by the heterogeneous system nZVI/PDS and concluded that the initial pH had the most significant effect on MP degradation. The optimal experimental conditions predicted by the RSM were as follows: initial pH 2.75, [nZVI] 0 = 2.87 mM, [PDS] 0 = 2.18 mM (MP degradation level of 95.30%). First- and second-order kinetic fits were performed for different initial pH levels and different concentrations of MP, nZVI, and PDS. It was determined that k = 0.0365 min−1 (R2 = 0.984) when the initial pH was 3, [PDS] 0 = 2 mM, [MP] 0 = 20 mg L−1, and [nZVI] 0 = 3 mM (MP degradation level of 94.25%). The rest of the conditions were more closely fitted to the second-order reactions. The effects of different concentrations of anions and humic acid (HA) on the MP degradation level and k were examined, and it was found that Cl− could promote MP degradation to 97.69% (increased by 3.65%) and increase the k in accordance with the first-order reaction kinetics (0.0780 min−1, R2 = 0.991). Finally, the analysis of intermediates revealed 5 reaction pathways and 7 reaction intermediates, which inferred a possible reaction mechanism with the recycling performance of nZVI. In this paper, the superiority of nZVI/PDS for the purposes of activating MP degradation was affirmed. The presence of Cl− can enhance the level of MP degradation was confirmed, which provides a new direction for future practical engineering applications. [Display omitted] • nZVI/PDS can improve the MP degradation rate to 95.42% (k = 0.0365 min−1). • First- and second-order kinetics were analyzed for all MP degradation reactions. • The optimal condition was derived in accordance with first-order reaction kinetics. • The addition of Cl− increased the MP degradation rate by nZVI/PDS to 97.69%. • Cl−/nZVI/PDS was in accordance with the first-order kinetics (k = 0.0780 min−1). [ABSTRACT FROM AUTHOR]

Two-dimensional anatase TiO2 hollow nanoplates were firstly synthesized through a facile synthesis route by using α-Fe2O3 nanoplates as removable templates. Two-dimensional hollow TiO2 nanoplates with different ratios of anatase and rutile phases were obtained by adjusting the calcining temperature. The average diameters were around 600 nm, and the shell thickness was approximately 30 nm. The photocatalytic performance of TiO2 was investigated by decomposing rhodamine B under simulated sunlight. Among the TiO2 samples, the anatase TiO2 hollow nanoplates manifested a significant enhancement in the photocatalytic performances. The excellent catalytic performance can be attributed to the unique structure of the two-dimensional anatase TiO2 hollow nanoplates, including a large surface area and increased dye-photocatalyst contact areas as well as more active sites for photodegradation. [ABSTRACT FROM AUTHOR]

Two-dimensional nanosheets with high specific surface areas and fascinating physical and chemical properties have attracted tremendous interests because of their promising potentials in both fundamental research and practical applications. However, the problem of developing a universal strategy with a facile and cost-effective synthesis process for multi-type ultrathin 2 D nanostructures remains unresolved. Herein, we report a generalized low-temperature fabrication of scalable multi-type 2 D nanosheets including metal hydroxides (such as Ni(OH)2, Co(OH)2, Cd(OH)2, and Mg(OH)2), metal oxides (such as ZnO and Mn3O4), and layered mixed transition-metal hydroxides (Ni-Co LDH, Ni-Fe LDH, Co-Fe LDH, and Ni-Co-Fe layered ternary hydroxides) through the rational employment of a green soft-template. The synthesized crystalline inorganic nanosheets possess confined thickness, resulting in ultrahigh surface atom ratios and chemically reactive facets. Upon evaluation as electrode materials for pseudocapacitors, the Ni-Co LDH nanosheets exhibit a high specific capacitance of 1087 F g−1 at a current density of 1 A g−1, and excellent stability, with 103 % retention after 500 cycles. This strategy is facile and scalable for the production of high-quality ultrathin crystalline inorganic nanosheets, with the possibility of extension to the preparation of other complex nanosheets. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic properties of the one-dimensional spin-1 ferromagnetic Heisenberg model are investigated by Green''s function method. The magnetic properties of the system are treated by the random phase approximation for the exchange interaction term, and the Anderson–Callen approximation for the single-ion anisotropy term. The critical temperature, magnetization, and susceptibility are found to be dependent of the anisotropies. Our results are in agreement with the other theoretical results. [Copyright &y& Elsevier]

Polyvinyl alcohol (PVA) is a biodegradable material that can be degraded under natural conditions. In this study, a sustained-release agent (SRA) was prepared from calcium compounds and PVA (PVA-Ca) to effectively degrade long-chain fatty acids in food waste (FW) and improve the performance of anaerobic digestion (AD). The most appropriate materials and conditions for synthesizing Ca-SRA were chosen according to the characteristics of the sample and changes in the electrical conductivity of a solution of the SRA. The calcium release kinetics were analyzed by curve fitting. Moreover, analytical methods were used to analyze the formation mechanism of PVA-Ca. Finally, the effect of PVA-Ca on the performance of AD was investigated. The results showed that the most suitable materials for preparing the Ca-SRA were Ca(OH) 2 powder and PVA1799. The most suitable synthesis conditions were freezing for 24 h at −20 °C and thawing for 24 h with one freeze–thaw cycle. PVA-Ca achieved rapid release during the first 48 h, which corresponded to first-order kinetics (k = 0.0354 h−1). The release of Ca2+ corresponded to changes in pH and the concentration of volatile fatty acids during hydrolysis and acidification of FW. After PVA-Ca was added, the duration of the system lag phase was significantly shortened to 10 days, the methane yield per unit load was increased from 238.2 to 489.3 mL g−1 volatile solids(VS), and the kinetic constant of AD of FW was 0.083 day−1. Adding PVA-Ca could increase the methane yield by 98.82%. Moreover, the value of T 90 was reduced to a maximum of about 16 days. PVA-Ca was successfully employed in the AD of FW for the first time. [Display omitted] [ABSTRACT FROM AUTHOR]

The 2019 Mw 7.5 New Ireland earthquake occurred at an equatorial area where the dense vegetation prevents remote sensing techniques such as C- or X-band interferometric synthetic aperture radar (SAR) from acquiring coherent phase measurements. Therefore, in this paper, multiple remote sensing techniques including the L-band interferometric SAR, the range and azimuth offset tracking of SAR intensities, and the offset tracking of optical images were employed to map its co-seismic deformation field and to determine the slip distribution. The surface rupture was clearly and consistently captured by all offset observations, with the ground fault trace striking at an angel of 315° and extending over 10 km. An iterative weighting strategy based on the residual root mean square of inversions using individual datasets was developed to determine the relative weight of each dataset, allowing for the joint inversion of the fault geometry, the refinement of the dip angle, and the determination of the best fitting slip distribution. The resultant model indicates a nearly left-lateral strike-slip motion on the Weitin fault that ruptured to the surface with a maximum slip of 6.10 m, occurring at a depth of ~10 km, and a geodetic moment release of 1.03 × 1020 Nm, corresponding to a magnitude of Mw 7.31. The distribution of aftershocks shows about 70% of aftershocks were located in the area with increased Coulomb failure stress and few aftershocks in the subduction zone to the south of the Weitin fault were triggered by this event. [ABSTRACT FROM AUTHOR]

Satellite radar imagery can record surface deformation over a wide range in both phase and amplitude formats, with Interferometric Synthetic Aperture Radar (InSAR) achieving millimetre accuracy. Based on these satellite radar observations, landslide detection at a large scale can be enhanced, which is beneficial to landslide risk assessment and disaster mitigation. However, there are still several challenges in the landslide detection with satellite radar observations. This talk presents an automated SAR-based landslide detection system under development which addresses the five main challenges of conventional InSAR for landslide detection.The first challenge is dense vegetation that affects the coherence of SAR data. The effects can be weakened by use of SAR imagery with a long wavelength (e.g. S-band or L-band), a short temporal resolution, and/or a high spatial resolution (e.g. 1 m or even higher), and/or advanced InSAR time series. The second challenge is to deal with landslides with large deformation gradients, which can be addressed by SAR offset tracking and range split-spectrum interferometry (RSSI) methods with relatively low precision. We have developed an integrated approach to combine the RSSI and conventional InSAR to capture the large surface displacements of fast-moving landslides more precisely. Atmospheric effects represent another challenge of conventional InSAR for landslide detection, especially in mountain areas. The Generic Atmospheric Correction Online Service (GACOS) developed at Newcastle University is used to reduce atmospheric effects on radar observations and simplify the following time series analysis. The fourth challenge is the impacts of SAR geometry such as shadow and layover. The impacts can be pre-analysed using a high-resolution external DEM. Since very high-resolution (VHR) DEMs are often not available whilst processing VHR radar images (e.g. 1m or higher TerraSAR-X), a machine learning approach has been developed to identify water bodies, shadow and layover areas. The geometry impacts can be weakened with the joint use of descending and ascending tracks, different tracks with different incidence angles, or radar images from different radar missions. The fifth challenge is topographic effects in areas with high buildings or steep slopes, which could easily lead to phase unwrapping errors. A baseline linear combination approach has been developed to address it. In our automated SAR-based landslide detection system under development, the GACOS-assisted InSAR time series technique is employed to delimit deformation acceleration zones and detect extremely-slow-to-slow moving landslides. SAR offset tracking and RSSI are used in parallel to capture large displacements and detect moderate-to-fast moving landslides. Machine learning algorithms are developed to automatically map post-event landslides triggered by earthquakes or heavy rains. [ABSTRACT FROM AUTHOR]

Three major subduction earthquakes occurred on March 20, 2012 (Mw 7.4), February 16, 2018 (Mw 7.2), and June 23, 2020 (Mw 7.4) in the southwestern coast of Mexico, which caused fatalities, casualties, considerable damage, and raised safety concerns about future seismic hazards. We use satellite geodetic observations to invert for the slip distributions of the three events and then investigate their interactions. Coulomb Failure Stress (CFS) induced by their slip both on surrounding thrust and normal faults are calculated. The positive CFS changes, along with the spatial‐temporal seismicity evolution, approximate earthquake recurrence rate and interseismic coupling, collectively indicate an increased possibility of a near‐future rupture around the areas between the 2018 and 2020 events in Oaxaca. Furthermore, there is a lowered chance of shallow coastal or offshore normal earthquakes but an increased chance of inland normal ruptures. Plain Language Summary: Large earthquakes result in stress changes, which can induce or retard regional seismic activity or even trigger other earthquakes. Therefore, understanding historical and recent earthquakes and their associated stress changes are crucial in the evaluation of future seismic hazards. One of the most popular and intuitive ways to relate past and future events is to calculate the Coulomb stress changes during an earthquake and a failure criterion can be established by considering the geometry of nearby faults and the stress changes induced by past events. This requires a detailed knowledge of the amount and direction of slip by which the main fault has slipped during its past ruptures. In this study, we use geodetic surface displacement measurements to invert for the slip distribution and the interactions of three subsequent subduction earthquakes in the southwestern coast of Mexico. We then evaluate the future seismic hazard of the region by considering Coulomb failure stress changes, spatial‐temporal regional seismic activities, historic earthquake records and approximate earthquake recurrence rate. The results show increased chances of a near‐future reverse rupture around Santa Catarina Juquila, Oaxaca and inland normal ruptures, but a lowered chance of shallow coastal or offshore normal ruptures. Key Points: Slip distribution and interactions of three recent subduction earthquakes in Mexico revealed from radar observationsIncreased probability of a near‐future major earthquake around areas between the 2018 and 2020 events in OaxacaLowered chance of shallow coastal or offshore normal earthquakes but increased chance of inland normal ruptures [ABSTRACT FROM AUTHOR]

Three major subduction earthquakes occurred on March 20, 2012 (Mw 7.4), February 16, 2018 (Mw 7.2), and June 23, 2020 (Mw 7.4) in the southwestern coast of Mexico, which caused fatalities, casualties, considerable damage, and raised safety concerns about future seismic hazards. We use satellite geodetic observations to invert for the slip distributions of the three events and then investigate their interactions. Coulomb Failure Stress (CFS) induced by their slip both on surrounding thrust and normal faults are calculated. The positive CFS changes, along with the spatial‐temporal seismicity evolution, approximate earthquake recurrence rate and interseismic coupling, collectively indicate an increased possibility of a near‐future rupture around the areas between the 2018 and 2020 events in Oaxaca. Furthermore, there is a lowered chance of shallow coastal or offshore normal earthquakes but an increased chance of inland normal ruptures. Plain Language Summary: Large earthquakes result in stress changes, which can induce or retard regional seismic activity or even trigger other earthquakes. Therefore, understanding historical and recent earthquakes and their associated stress changes are crucial in the evaluation of future seismic hazards. One of the most popular and intuitive ways to relate past and future events is to calculate the Coulomb stress changes during an earthquake and a failure criterion can be established by considering the geometry of nearby faults and the stress changes induced by past events. This requires a detailed knowledge of the amount and direction of slip by which the main fault has slipped during its past ruptures. In this study, we use geodetic surface displacement measurements to invert for the slip distribution and the interactions of three subsequent subduction earthquakes in the southwestern coast of Mexico. We then evaluate the future seismic hazard of the region by considering Coulomb failure stress changes, spatial‐temporal regional seismic activities, historic earthquake records and approximate earthquake recurrence rate. The results show increased chances of a near‐future reverse rupture around Santa Catarina Juquila, Oaxaca and inland normal ruptures, but a lowered chance of shallow coastal or offshore normal ruptures. Key Points: Slip distribution and interactions of three recent subduction earthquakes in Mexico revealed from radar observationsIncreased probability of a near‐future major earthquake around areas between the 2018 and 2020 events in OaxacaLowered chance of shallow coastal or offshore normal earthquakes but increased chance of inland normal ruptures [ABSTRACT FROM AUTHOR]

Large and shallow strike-slip earthquakes produce striking ground ruptures, damaging roads and infrastructure but providing great opportunities for examining the fault's structure. After the 2022 Mw 6.7 Menyuan earthquake, we observed abundant surface fractures by a combination of optical remote sensing, radar offset and unmanned aerial vehicle measurements. These fractures reveal a complex fault structure including apparent bending geometries and bifurcating branches, which are essential to understanding the mechanisms of faulting. In this paper, we used triangular dislocations to construct the fault geometry that reflected the distribution of measured strike changes but avoided unexcepted discontinuities and overlaps where the fault bent. The modeled fault geometry revealed an extensional releasing bend which was responsible for the southward branching of the fault rupture at its western edge. Our results also demonstrated the potential to explain the occurrence of aftershock clusters and to infer their fault geometries through the correlation analysis of the aftershock distribution and the slip induced stress field. The triangular dislocation model also enabled the calculation of the fault plane roughness and its spatial variation which directly controlled the fault slip magnitude and rupture termination. These analyses reveal an unprecedented level of detail of the fault structure and slip mechanics and, to some extent, offer insights into the physical processes and structural properties of crustal faults in the Earth's shallow crust. • Curved and branched surface ruptures were observed by multi-sourced geodetic data. • The fault structure was related to the distribution and clustering of aftershocks. • The fault rupture forked southward at its western end because of a releasing bend. • The fault plane roughness controlled the slip propagation and termination. [ABSTRACT FROM AUTHOR]

Abstract Tube-like nanostructure, especially carbon nanotube, usually has distinguished properties, making itself useful substrate for producing hybrid and composite materials with various applications. In this study, we proposed a space-confined self-oriented reaction in a single-ended reactor for the directional-induced decomposition of plate-like Zn-Fe double metal cyanide nanostructure. Two novel different kinds of magnetic self-supported carbon-based nanocomposites, FeC nanoparticle@ZnCN 2 nanotube composite and austenite/Fe nanoparticle@carbon nanotube composite, were respectively synthesized. These nanotubes subjected to the plate-like precursor were short and non-intertwined, unlike most carbon nanotubes reported before. It was found that reactor geometry plays key roles in the self-oriented growth of these carbon-based nanoarrays and fine tubular reactors with different reducing aspect ratio (AR) values result in different nanocomposite products. [ABSTRACT FROM AUTHOR]

This paper develops a missile formation algorithm. The general form of time-varying formation constraints in three-dimensional space for missiles is deduced, and the formation control under time-varying position constraints is transformed into constrained optimization problem. Based on discretization of trajectory and optimization of control outputs, an approach to design optimal feedback control algorithm is presented. The three degree of freedom simulation results of the missiles obtained by constraint optimization show that the formation strategy proposed in this paper is feasible in missile formation control under complex time-varying constraint. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). Post-publication, the editor discovered suspicious changes in authorship between the original submission and the revised version of this paper. In summary, the author names Yan Zhang (new First Author and Corresponding Author), Fangmin Yuan, Huipeng Zhai and Chuang Song were added to the revised paper without explanation and without exceptional approval by the journal editor, which is contrary to the journal policy on changes to authorship. The editor reached out to the authors for an explanation, but they failed to provide a satisfactory explanation to these changes. In addition, it appears that Roza Poursoleiman was claiming an affiliation with Sun-Life Company, Baku, Azerbaijan. When questioned, the author was unable to provide convincing evidence of the existence and nature of this company. Overall, the editor feels that the findings of the manuscript cannot be relied uon and that the article needs to be retracted. [ABSTRACT FROM AUTHOR]

Abstract: The effect of magnetic field on the magnetic properties of the one-dimensional spin-1 ferromagnetic Heisenberg model is studied by the double-time Green’s function method. The magnetization and susceptibility are obtained within the Callen approximation. The zero-field susceptibility is as a decreasing function of the temperature . The magnetization increases in the whole field region, but the susceptibility maximum decreases. The position of the susceptibility maximum is both solved analytically and fits well to be a power law at low fields and to be linear increasing at high fields. The height decreases as a power law with increasing. The exponents obtained in our results agree with the other theoretical results. Our results are roughly in agreement with the results obtained in the experiment of Ni(OH)(NO3)H2O. [Copyright &y& Elsevier]

A self-starting, passively mode-locked all-fibre ring laser based on the homemade Er3+/Yb3+codoped phosphate glass fibre is reported. Dual-pump sources were used to achieve the mode-locked operation in the experiment. The fundamental mode-locked pulse repetition rate is 10.67 MHz. The pulse duration, assumed as the fit of hyperbolic secant pulse shape, is 5.82ps. We also observe the multi-pulse output of the fibre laser. [ABSTRACT FROM AUTHOR]

The 2019 M w 7.1 Ridgecrest earthquake opens an opportunity to investigate how soon we can produce a reliable fault geometry and subsequently a robust source model based on high-rate Global Positioning System (GPS) data. In this study, we conduct peak ground displacement (PGD) magnitude scaling, real-time centroid moment tensor (CMT) calculation and rapid kinematic slip inversion. We conclude that a four-station PGD warning with a magnitude of M w 7.03 can be issued at 24 s after initiation of the rupture. Fast CMT inversion can initially recover the correct nodal planes at 30 s. The kinematic slip model reveals that the M w 7.1 earthquake is a predominant dextral strike-slip event with both normal and thrust components resolved. The earthquake shows a bilateral rupture with a low propagation speed of ∼2.1 km s−1 and a slip maxima of ∼4 m. The total moment is 5.18 × 1019 N m (M w 7.11). We further suggest that a reasonable source model will be available in a simulated real-time mode within 30 s after the earthquake occurring, without using full high-rate GPS waveforms. This research highlights the significance of high-rate GPS for rapid earthquake response and modelling of kinematic rupture, which is also generalized by the hypothetical real-time GPS analysis for the 2016 M w 7.8 Kaikoura earthquake and the 2010 M w 7.2 El Mayor-Cucapah earthquake. [ABSTRACT FROM AUTHOR]

Although the Papuan fold and thrust belt (PFTB) is thought to accommodate convergence between the Pacific and Australian plates, the possible strain partitioning and its kinematic controls in the region are poorly understood. On 25 February 2018, a devastating Mw 7.5 earthquake jolted the southern area of the PFTB, central Papua New Guinea. The detailed imaging of the source parameters of this large earthquake is an urgent demand for a better understanding of the tectonism in the region. Here we used spaceborne interferometric synthetic aperture radar data to carefully determine the possible ruptured faults and associated fault geometries and further estimated the detailed slip of the 2018 Mw 7.5 earthquake. We find that the earthquake involved multiple faults failure, and a four‐segment fault model can reasonably produce the complex coseismic deformation, especially the observed bimodal displacements. The earthquake was dominated by reverse fault motion, and significant slip of up to ~0.7 m was documented on faults extending at depths great than 25 km. An integrated analysis of the fracture complexities suggests that possible strain partitioning in the PFTB could be tightly coupled with regional fault geometries and lithospheric properties. Our findings on the deep brittle failures suggest that crustal shortening across the PFTB could primarily control the growth of fold and thrust belt in the central Papua New Guinea. Key Points: Complete coseismic surface deformation generated from InSAR helps determine ruptured faults and constrain the complex source parametersThe 2018 Mw 7.5 Papua New Guinea earthquake was characterized by deep‐seated reverse faulting with ruptures extending into depths of 25 kmThis event revealed the possible strain partitioning in the Papuan fold and thrust belt and can help explain its growth [ABSTRACT FROM AUTHOR]

In the era of big data, various factors (particularly meteorological factors) have been considered in power load prediction, and the result shows a clear discrepancy in timescales. To capture the complicated multiscale relationship between power load and related factors, a novel multifactor and multiscale method is proposed for power load forecasting. Three primary steps are implemented: (1) multifactor analysis to select predictive factors via statistical tests; (2) multiscale analysis to extract scale-aligned components via multivariate empirical mode decomposition; and (3) power load prediction, including individual prediction at each timescale and ensemble prediction across different timescales. The empirical study focuses on the power load of Nanyang and indicates that the proposed multifactor and multiscale learning paradigms statistically outperform their corresponding original techniques (without multifactor and multiscale analysis) and semi-improved variants (with either multifactor or multiscale analysis) in terms of prediction accuracy. [ABSTRACT FROM AUTHOR]

The synthesis of ultrathin magnetic nanosheets is significant for the development of next-generation nanodevices but remains to be a big challenge. Herein, we present facile approaches for large-scaled production of cell-unit-thick single-crystalline iron oxide nanostructures. The ultrathin hematite (α-Fe 2 O 3 ) nanosheets with unit-cell thickness of 1.3 nm are firstly synthesized using a metal-ion-intervened hydrothermal method. Then the α-Fe 2 O 3 nanosheets are converted to magnetic maghemite ( γ -Fe 2 O 3 ) nanosheets with unit-cell thickness of 0.8 nm by a simple calcination process. The Li-ion battery studies reveal that unit-cell-thick γ-Fe 2 O 3 nanosheets exhibit great enhanced electrochemical performances with high specific capacitance approaching to its theoretical value and excellent cycling stability. [ABSTRACT FROM AUTHOR]

A bio-inspired detector based on the artificial neural network (ANN) and genetic algorithm is proposed in the context of a coherent optical transmission system. The ANN is designed to mitigate 16-quadrature amplitude modulation system impairments, including linear impairment: Gaussian white noise, laser phase noise, in-phase/quadrature component imbalance, and nonlinear impairment: nonlinear phase. Without prior information or heuristic assumptions, the ANN, functioning as a machine learning algorithm, can learn and capture the characteristics of impairments from observed data. Numerical simulations were performed, and dispersion-shifted, dispersion-managed, and dispersion-unmanaged fiber links were investigated. The launch power dynamic range and maximum transmission distance for the bio-inspired method were 2.7 dBm and 240 km greater, respectively, than those of the maximum likelihood estimation algorithm. Moreover, the linewidth tolerance of the bio-inspired technique was 170 kHz greater than that of the k-means method, demonstrating its usability for digital signal processing in coherent systems. [ABSTRACT FROM AUTHOR]

In recent years, the usage of new technologies in distributed generation is growing due to the electricity industry movement towards privatization and decentralized production of electric energy as well as competition among the new technologies. Microgrids are practical examples of the concept of decentralized production. Also, the employment of renewable energies is rapidly promoted due to the construction barriers of conventional power plants. Therefore, selecting and applying the appropriate technologies in planning and careful design of the type and capacity of generation and energy storage units are important. This paper proposed a robust model for day-ahead production scheduling of electrical and thermal units in a large-scale virtual power plant comprising a large number of distributed generation units and consumers accompanied by energy storage. To consider real conditions, the uncertainty of electrical demands is modeled by employing scenario-based analysis and probabilistic programming. So, five scenarios are created and modeled. In addition, two operation mode of a microgrid is considered connected and islanded modes. The objective function consists of total profit resulting from the daily operation of all units. The results confirm the applicability and effectiveness of the proposed model. Moreover, the total profit of the connected mode of the microgrid is about 20% more than the islanded mode, in all scenarios, and the cumulative profit cash flow of the connected mode is about 31% more than islanded mode. [ABSTRACT FROM AUTHOR]

Effective pretreatment of corn straw is essential to improve its anaerobic digestion (AD), NaOH-cellulase pretreatment of corn straw may be effective in enhancing its AD at the theoretical level. In this study, the effects of NaOH-cellulase treatment on corn straw degradation rate and sugar yield were investigated. Moreover, the microstructure analysis of corn straw was performed to determine the treatment mechanism. Gas production, methane content, kinetic fitting, and stability of AD of corn straw were compared before and after pretreatment to determine the efficacy of NaOH-cellulase pretreatment. The results showed the highest straw degradation rate (230% higher than that of the control group) when hydrolyzed by 6.0% of NaOH as 0.10 g·g−1 dry matter cellulase, and the biomethane content in corn straw pretreated with 6.0% of NaOH-elution-cellulase reached 70.1%. The biomethane yields of the corn straw after NaOH-elution-enzymatic hydrolysis using 4% of NaOH was 317 ± 11 mL·g−1 VS. The efficiency of AD after 4.0% of NaOH pretreatment was better than that after 6.0%-NaOH pretreatment, where the anaerobic system was more stable. In this study, NaOH-cellulase was used for the first time to pretreat corn straw, which effectively improved its AD. [Display omitted] • NaOH–cellulase can usefully increase corn straw anaerobic digestion gas production. • The optimal conditions were 6% of NaOH, 0.10 g·g−1 cellulase, and 5% of substrate. • The highest straw degradation rate was 230% more than that of the control group. • The methane production of the straw pretreated with NaOH–cellulase was 317 mL·g−1 VS. • The methane content of the straw pretreated with 6% of NaOH–cellulase reached 70.1%. [ABSTRACT FROM AUTHOR]

Abstract: One-dimensional single-ion anisotropic ferromagnet with spin-1 is investigated by means of Green''s function treatment in this paper. The model Hamiltonian includes a Heisenberg ferromagnetic term, an external magnetic field, and a second-order single-ion anisotropy. The magnetic properties of the system are treated by the random phase approximation for the exchange interaction term and the Anderson–Callen approximation for the anisotropy term. Our paramagnetic results are in agreement with the other theoretical results. [Copyright &y& Elsevier]

The M w 7.6 Chi-Chi earthquake struck central western Taiwan in 1999. The rupture was complex with several dislocations along the 100-km long Chelungpu thrust fault. Revisiting this earthquake is a challenge, as the precision and coverage of the data sets available are quite poor. Furthermore, the topographic and vegetation coverage complexity of the area prevents coherent radar images. In this paper, radar and optical images, and terrestrial geodetic measurements, were utilised to study the fault. The Particle Swarm Optimization and Okada Inversion (PSOKINV) geodetic inversion package was used with the generalized Akaike's Bayesian Information Criterion (gABIC) to precisely determine the slip distribution and relative weighting of datasets. Differences in results using the data sets jointly or separately (e.g., under-estimation due to InSAR, inconsistencies in SPOT offsets, smoother slip distribution with gABIC weighting) are observable. Most of the energy was released in the northern part of the fault, where the strike veers toward the east, and mainly at depths less than 4 km. The PSOKINV-gABIC approach is viable for the study of complicated cases such as the Chi-Chi earthquake and can significantly benefit the weight determination and physical realism of the fault geometry. [ABSTRACT FROM AUTHOR]

Rapid population growth combined with recent drought events and decades of political instability have left the residents of Kabul facing water scarcity, significantly relying on groundwater. Groundwater overexploitation might have induced various magnitudes of ground subsidence, however, to date, no comprehensive study of ground subsidence in Kabul has been conducted. In this study, we investigated the spatio-temporal evolution of ground deformation phenomena and its main governing processes in Kabul from 2014 to 2019 using C-Band Sentinel-1 derived Interferometric Synthetic Aperture Radar (InSAR) time-series from both ascending and descending orbits to extract the two-dimensional (2D) surface displacement field. Four subsidence bowls were distinguished with highly variable spatial extents and deformation magnitudes over four separate aquifer basins, with the maximum value of −5.3 cm/year observed in the Upper Kabul aquifer basin. A wavelet analysis suggests that there is a strong correlation between the groundwater level variations and subsidence. Investigation of hydrogeological data further reveals that the observed subsidence could be attributed to the presence of highly compressible clayey soils. This detailed space-borne regional survey provides new insights into the main governing mechanism of land subsidence in Kabul and may direct better mitigation plans of potential hazards. [ABSTRACT FROM AUTHOR]