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Segmented dynamic wireless power transfer (DWPT) systems can solve the problems of large battery size, long charging time, and the limited driving range of electric vehicles (EVs). Aiming at the load voltage fluctuation caused by the mutual inductance drop when moving over two adjacent transmitting coils, this paper proposes a novel segmented DWPT system with dual receiver topology circuits. The current phase difference between two adjacent transmitting coils is controlled to 180 degrees. The dual receiver topology circuits are in series to improve the output voltage. According to the real-time position of the EV, the system has two working modes under the control of the proposed topology, which consists of three fully controlled components and six diodes. Finally, experiments were carried out and the obtained results show that the designed topology is effective when it comes to reducing the voltage fluctuation when passing two adjacent transmitting coils. In addition, the topology is able to maintain a high transmission efficiency with a maximum efficiency of 87.68%. [ABSTRACT FROM AUTHOR]

Analysis of properties related to spin textures, such as the magnetic vortex state, is mainly based on spin configuration data, which is directly related to magnetic parameters involved in the system's Hamiltonian. Here, we focus on magnetic parameter estimation by implementing the machine learning (ML) approach, especially on magnetic force microscopy (MFM) images of vortex states within nanodots generated by micromagnetic simulation. The exchange constant Aex and saturation magnetization Ms as well as exchange length as a reduced parameter Lex(Aex, Ms) are estimated by different convolutional neural network (CNN) models. We also evaluated the CNN models, trained on simulated MFM images with non-zero temperature, on a reference experimental MFM image and found the performance to a satisfactory level of accuracy. Moreover, the same CNN models, trained for binary classification of vortex states based on helicity from MFM images, successfully identified the vortex helicity from simulated as well as experimental MFM images. These findings show the possible application of ML in magnetic parameter estimation and the analysis of magnetic vortex states simply with images obtained from this commonly used imaging technique that is significant in efficient investigation of material properties based on intrinsic parameters for spintronic device applications. [ABSTRACT FROM AUTHOR]

Currently, there is a large deviation between official road freight data and real road freight performance at a subnational level in China. In order to deal with this deviation, the new concept of local freight tonnage and ton-kilometers is presented in this paper based on the territoriality principle, where either the origin or the destination of goods transported is local. Also, the statistic procedures and estimation models of the local freight tonnage and ton-kilometers are proposed based on five accessible basic datasets. Finally, an empirical study in Sichuan province of China is conducted. The statistical results show that there is a large amount of local freight transported by local non-commercial trucks and non-local trucks, which is ignored in the existing road freight statistics. Especially, the higher the level of local economic development, the greater the deviation between the official road freight data and the real road freight performance at a subnational level. [ABSTRACT FROM AUTHOR]

Vulcanization is a pivotal process of tire manufacturing, endowing the uncured tire with exquisite surface pattern and superior performance by converting rubber property from plasticity to elasticity. However, the defects of incomplete expansion, asymmetric structure, and vapor condensation deposition in the existing vulcanization technology inferiorly affect the uniformity and dynamic balance performance of tires. In our paper, a novel tire curing equipment, i.e., vulcanized inner mold drum (VIMD) is designed to improve the traditional vulcanization process for automobile tires. The structure design of the drum tiles, the telescopic mechanism and the transmission mechanism, and the finite element simulation analysis and reliability check of the key components are carried out. The contraction ratio is obviously increased by increasing the number of drum tiles and adopting the structural design method of arranging the link mechanisms cross-symmetrically. The ingenious design of the dual cam link mechanism enables the movement of the mechanism to proceed in an orderly manner, effectively avoids complicated controlling design. The design of self-locking structure considerably reduces the force of the links and improves the overall dimensional accuracy. The results suggest that the VIMD has excellent dimensional accuracy and structural stability. A new type equipment for tire vulcanization is proposed. The contraction ratio is obviously increased by increasing the number of drum tiles, and adopting the structural design method of arranging the link mechanisms cross-symmetrically. The ingenious design of the cylindrical cam track enables the movement of the mechanism to proceed in an orderly manner, effectively avoiding the interference of parts. The design of the dual cam link mechanism avoids complicated controlling design and effectively improves space utilization. The design of self-locking structure considerably reduces the force of the links and improves the overall dimensional accuracy. [ABSTRACT FROM AUTHOR]

Performing research on the variation in lake water on the Qinghai–Tibet Plateau (QTP) can give the area's ecological environmental preservation a scientific foundation. In this paper, we first created a high-precision dataset of lake water level variation every 10 days, from July 2002 to December 2022, using multi-source altimetry satellite SGDR data (Envisat RA-2, SARAL, Jason-1/2, and Sentinel-3A/3B SRAL), which integrated the methods of atmospheric path delay correction, waveform re-tracking, outlier detection, position reduction using a height difference model, and inter-satellite deviation adjustment. Then, using Landsat-5 Thematic Mapper, Landsat-7 Enhanced Thematic Mapper, and Landsat 8 Operational Land Imager data, an averaged area series of Lake Qinghai (LQ) from September to November, each year from 2002 to 2019, was produced. The functional connection between the water level and the area was determined by fitting the water level–area series data, and the lake area time series, of LQ. Using the high-precision lake water level series, the fitted lake surface area time series, and the water storage variation equation, the water storage variation time series of LQ was thus calculated every 10 days, from July 2002 to December 2022. When the hydrological gauge data from the Xiashe station and data from the worldwide inland lake water level database are used as references, the standard deviations of the LQ water level time series are 0.0676 m and 0.1201 m, respectively. The results show that the water storage of LQ increases by 11.022 × 109 m3 from July 2002 to December 2022, with a growth rate of 5.3766 × 108 m3/a. The growth rate from January 2005 to January 2015 is 4.4850 × 108 m3/a, and from January 2015 to December 2022, the growth rate is 8.9206 × 108 m3/a. Therefore, the increased rate of water storage in LQ over the last 8 years has been substantially higher than in the previous 10 years. [ABSTRACT FROM AUTHOR]

The lockdowns from the coronavirus disease of 2019 (COVID-19) have led to a reduction in anthropogenic activities and have hence reduced primary air pollutant emissions, which were reported to have helped air quality improvements. However, air quality expressed by the air quality index (AQI) did not improve in Shanghai, China, during the COVID-19 outbreak in the spring of 2022. To better understand the reason, we investigated the variations of nitrogen dioxide (NO2), ozone (O3), PM2.5 (particular matter with an aerodynamic diameter of less than 2.5 μm), and PM10 (particular matter with an aerodynamic diameter of less than 10 μm) by using in situ and satellite measurements from 1 March to 31 June 2022 (pre-, full-, partial-, and post-lockdown periods). The results show that the benefit of the significantly decreased ground-level PM2.5, PM10, and NO2 was offset by amplified O3 pollution, therefore leading to the increased AQI. According to the backward trajectory analyses and multiple linear regression (MLR) model, the anthropogenic emissions dominated the observed changes in air pollutants during the full-lockdown period relative to previous years (2019–2021), whereas the long-range transport and local meteorological parameters (temperature, air pressure, wind speed, relative humidity, and precipitation) influenced little. We further identified the chemical mechanism that caused the increase in O3 concentration. The amplified O3 pollution during the full-lockdown period was caused by the reduction in anthropogenic nitrogen oxides (NOx) under a VOC-limited regime and high background O3 concentrations owing to seasonal variations. In addition, we found that in the downtown area, ground-level PM2.5, PM10, and NO2 more sensitively responded to the changes in lockdown measures than they did in the suburbs. These findings provide new insights into the impact of emission control restrictions on air quality and have implications for air pollution control in the future. [ABSTRACT FROM AUTHOR]

To analyze the electromagnetic scattering characteristics of stealth targets, radar cross section (RCS) values of the typical stealth aircraft model are evaluated by electromagnetic simulation. Based on the RCS electromagnetic simulation results, RCS statistical histograms of the stealth aircraft model are created. For describing the RCS statistical characteristics of stealth aircrafts, a Weibull‐generalized gamma mixture distribution model is proposed in this study. Some special cases of the Weibull‐generalized gamma mixture distribution model are summarized. Utilizing the nonlinear least squares technique, fitting results of the proposed and conventional RCS distribution models for the RCS statistical characteristics of typical stealth aircarfts are compared. Mean square error test and R‐square (R2 ${R}^{2}$) test results show that the proposed distribution model obtains better fitting results than the conventional RCS distribution models, which indicates that the proposed distribution model is a more efficient RCS statistical model. [ABSTRACT FROM AUTHOR]

Vaccination is an important means to fight against the spread of the SARS-CoV-2 virus and its variants. In this work, we propose a general susceptible-vaccinated-exposed-infected-hospitalized-removed (SVEIHR) model and derive its basic and effective reproduction numbers. We set Hong Kong as an example and calculate conditions of herd immunity for multiple vaccines and disease variants. The model shows how the number of confirmed COVID-19 cases in Hong Kong during the second and third waves of the COVID-19 pandemic would have been reduced if vaccination were available then. We then investigate the relationships between various model parameters and the cumulative number of hospitalized COVID-19 cases in Hong Kong for the ancestral, Delta, and Omicron strains. Numerical results demonstrate that the static herd immunity threshold corresponds to one percent of the population requiring hospitalization or isolation at some point in time. We also demonstrate that when the vaccination rate is high, the initial proportion of vaccinated individuals can be lowered while still maintaining the same proportion of cumulative hospitalized/isolated individuals. [ABSTRACT FROM AUTHOR]

[Display omitted] • The β-In 2 S 3 / NDCN composites were rationally fabricated. • The composite photocatalyst realizes the efficient reduction performance of CO 2. • The heterojunction promotes the separation of carriers and accelerate the reaction. • The photocatalyst shows good stability and reusability in CO 2 reduction. The flaky carbon nitride containing nitrogen defects (NDCN) could effectively perform the photocatalytic reduction of carbon dioxide (CO 2) due to its abundant active sites. Reducing the recombination of electrons and holes was also a method of semiconductor photocatalyst design. A nanosphere ball-flower Indium sulfide (In 2 S 3) was synthesized via a simple hydrothermal approach, and then calcined to obtain the β-In 2 S 3 /NDCN heterojunction photocatalyst and applied for CO 2 photocatalytic reduction. The best total yield (carbon monoxide, CO: 20.32 μmol·g−1·h−1; methane, CH 4 : 2.12 μmol·g−1·h−1) could be obtained at the optimized 20% β-In 2 S 3 /NDCN under near room temperature and pressure and without using any sacrificial agents or promoters, almost 1.7 times higher compared with NDCN. The composite catalyst still exhibited excellent stability after four cycles. The improvement of excellent performance was due to not only the enhancement of fine CO 2 adsorption/activation and the light absorption ability, but also attributed to the formation of heterojunction, which accelerated the effective separation of electrons and holes. This work might provide a novel approach to design carbon nitride heterojunction photocatalysts with nitrogen defects for CO 2 utilization. [ABSTRACT FROM AUTHOR]

The conglomerate reservoir in Mahu sag, located in the northwest margin of Junggar basin, China, is of low porosity and permeability. Hydraulic fracturing is necessary to improve oil production efficiency. However, the influence of strong reservoir heterogeneity and large difference in gravel content on mechanical properties still needs study. In this study, uniaxial compression tests were conducted on the conglomerate in which the gravel diameter ranges from 2 to 26 mm. In these tests, a large number of micro-fractures were found to be generated evenly around gravels. Additionally, we found that as the gravel content increased, the uniaxial compressive strength and elastic modulus of conglomerate decreased, and the plasticity characteristics increased. The experimental results show that the gravel content is the key factor determining the mechanical properties of the conglomerate. When gravel content is less than the critical content (~ 14.61–31.72%), at which the brittle–plastic transition of rocks exists, the macro-mechanical properties are mainly influenced by the cementing material. When gravel content is greater than the critical gravel content (~ 78.50%), failure is determined by the Hertz contact stress among the gravels. When gravel content is between (~ 14.61–31.72%) and (~ 78.50%), Orowan additional stress is the main factor determining the mechanical mechanism of rock failure. This failure is closely related to gravel content and cementation strength between the gravel and matrix. Highlights: The gravel content is the key factor of the mechanical properties of conglomerate. As the gravel content increases, the uniaxial compressive strength and elastic modulus of conglomerate decrease. The micro fracture of rock is distributed around the gravel, which is closely related to the interaction between gravel and matrix. [ABSTRACT FROM AUTHOR]

In this article, a new Swerling‐chi/inverse generalized gamma composite distribution model is proposed for modeling the monostatic radar cross‐section (RCS) statistical characteristics of stealth aircraft. Under some conditions, the proposed distribution model can be reduced to the Fisher‐Snedecor ℱ distribution model and the Swerling‐chi distribution model. A typical stealth aircraft without radar absorption materials (RAM) is selected as an application for simulation using the adaptive cross approximation (ACA) technique. Based on the nonlinear least‐squares criterion, monostatic RCS statistical characteristics of the front sector of this aircraft are fitted using the proposed composite model. For the comparison purpose, monostatic RCS statistical characteristics of this aircraft are also fitted with the conventional RCS distribution models. Goodness‐of‐fit tests of the proposed distribution model and the conventional distribution models are analyzed in terms of the error‐of‐fit results and the R2 test results. Simulation results validate the efficiency and robustness of the proposed distribution model. [ABSTRACT FROM AUTHOR]

Facing abundant waste glass generation globally, closed-loop recycling is promising by substituting raw materials with recovered secondary materials. Adequate economic-environmental information is crucial to promote glass recycling. However, previous economic-environmental analysis predominantly concentrated on open-loop recycling; and distinctions among different glass categories were neglected. Hence, this study explored economic-environmental benefits of closed-loop recycling for different kinds of waste glass with techno-economic analysis and life-cycle assessment, covering transportation, crushing & separation, and waste utilization stages. Firstly, recycling status investigation identified waste flat glass (WFG) and waste packaging glass (WPG) as research objects, collectively representing over 90% of glass. Based on data inventory established through material and energy flow analysis, our further assessment reveals 11.6 USD/t economic benefits for WFG recycling and −6.9 to −0.6 USD/t for WPG; total environmental impact after standardization is −51% and −29% for WFG and WPG closed-loop recycling, respectively. Finally, scenario analysis highlights the importance of enhancing the separation efficiency of the crushing & separation stage and improving the ratio of substituting raw materials with waste in the waste utilization stage, which are the most efficient ways to increase economic and environmental benefits, respectively. Our work provides critical insights for targeted development of waste glass recycling industry. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Sodium doped flaky g-C 3 N 4 with nitrogen defects was rationally fabricated. • The photocatalyst realizes the efficient reduction performance of CO 2. • The introduction of nitrogen defects promotes the increase of active sites. • Sodium doping and flaky structure are conducive to electron transfer and accelerate the reaction. • The photocatalyst shows good stability and reusability in CO 2 reduction. Sodium doped flaky carbon nitride (g-C 3 N 4) with nitrogen defects (bmw-DCN-x) were synthesized via two steps method to enhance photocatalytic reduction of carbon dioxide (CO 2). After ball milling and calcination, dicyandiamide was evenly dispersed on the sodium chloride (NaCl) template to form a flaky structure. The NaCl not only provided part of sodium (Na) source for Na doped g-C 3 N 4 , but also introduced a large number of nitrogen (N) defects. Meanwhile, sodium hydroxide (NaOH) significantly enhanced Na doping. The bmw-DCN-30, a proportion of modified g-C 3 N 4 , showed heightened photo-reduction CO 2 performance, with satisfactory carbon monoxide (CO) and methane (CH 4) productivity at a rate of 30.6 μmol·g−1·h−1 and 5.4 μmol·g−1·h−1 respectively. This productivity was 15 and 11 times as much as that of bulky g-C 3 N 4 (BCN). The related characterizations confirmed that N defects produced more reactive sites and enhanced the adsorption capacity of carbon nitride to CO 2. The accompanying Na doping and flaky structure characteristics improved the optical absorption ability and the effective separation of photogenerated carriers. Accordingly, this work provides further insights into constructing modified materials based on carbon nitride for CO 2 reduction. [ABSTRACT FROM AUTHOR]

The development of drag reduction and self-cleaning technologies urgently needs the superhydrophobic films with high durability. However, due to hardness limitation, traditional polymer-based superhydrophobic films cannot achieve high durability. Here, a new strategy of "surface super-roughening of hard inorganic films" was proposed to achieve the integration of durability and hydrophobicity. By inducing the vertical growth of surface mounds, super-rough Ag-doped hafnium nitride films were prepared. This film had superhydrophobicity, high hardness, high wear resistance and high corrosion resistance. In addition, through the combination of experiments and simulations, we explained the microscopic mechanism of the vertical growth of surface mounds. [Display omitted] [ABSTRACT FROM AUTHOR]

We focus on the elliptic genera of level N at the cusps of a congruence subgroup for any complete intersection. Writing the first Chern class of a complete intersection as a product of an integral coefficient c1 and a generator of the 2nd integral cohomology group, we mainly discuss the values of the elliptic genera of level N for the complete intersection in the cases of c1 >, =, or < 0. In particular, the values about the Todd genus, Â-genus, and Ak-genus can be derived from the elliptic genera of level N. [ABSTRACT FROM AUTHOR]

Plant polyploidization increases the complexity of epigenomes and transcriptional regulation, resulting in genome evolution and enhanced adaptability. However, few studies have been conducted on the relationship between gene expression and epigenetic modification in different plant tissues after allopolyploidization. In this study, we studied gene expression and DNA methylation modification patterns in four tissues (stems, leaves, flowers and siliques) of Brassica napusand its diploid progenitors. On this basis, the alternative splicing patterns and cis-trans regulation patterns of four tissues in B. napus and its diploid progenitors were also analyzed. It can be seen that the number of alternative splicing occurs in the B. napus is higher than that in the diploid progenitors, and the IR type increases the most during allopolyploidy. In addition, we studied the fate changes of duplicated genes after allopolyploidization in B. napus. We found that the fate of most duplicated genes is conserved, but the number of neofunctionalization and specialization is also large. The genetic fate of B. napus was classified according to five replication types (WGD, PD, DSD, TD, TRD). This study also analyzed generational transmission analysis of expression and DNA methylation patterns. Our study provides a reference for the fate differentiation of duplicated genes during allopolyploidization. [ABSTRACT FROM AUTHOR]

The gain-driven emission in gain–loss coupling systems attains significant interest. In this work, we study the monochromatic oscillation of a gain–loss coupling system through a circuit model, where the monochromacy is manifested as the gain-driven synchronization of two coupled oscillators. The synchronized oscillation in this model is theoretically studied and experimentally manifested. Benefiting from the conceptual simplicity of a circuit model, a pair of asymmetric long-living states is found among the unstable gain-driven monochromatic oscillations, corresponding to bound states in the continuum of coupling physics. [ABSTRACT FROM AUTHOR]

For the requirement in container nursery culture that growing media should be achieved the appropriate degree compaction, this paper presents an experiment on the compaction dynamics of air-dried soil under repetitive drop shocks, as a preliminary step toward the mechanization of this compaction method. The drop height used to adjust the shock intensity included 2 mm, 4 mm, 5 mm and 6 mm. And the overall packing density of soil in a vertically stratified cylinder vessel and the local packing density in each layer were taken as indicators of soil compaction states. The stretched exponential function derived from KWW law than the empirical inverse-logarithmic function has been found to be more suitable for expressing the temporal evolution of soil compaction, according to the results of curve-fitting to test values of the overall and local density. It is inherent in this experimental configuration that the drop shock intensity even at a constant drop height varies with drop times, owing to the interaction between the soil packing itself and drop shocks caused by the combination of the packing and the container. But the function t/τf(t,H) is manifested as a straight line on the drop times t with the line slope related to the drop height H, so the soil compaction dynamics caused by its drop shocks and that under the condition with actively controlled intensity actually share the common relaxation law. In addition, the soil's one-dimensional distribution of local packing density showed a slight positive gradient as similar as monodisperse particles did. [ABSTRACT FROM AUTHOR]

Monitoring the pH in tumor lesions provides abundant physiological information. However, currently developed pH sensors only achieve sensitive detection in the settled response region around the pH transition point (pHt). To realize tumor pH monitoring with high sensitivity within a wider response region, reported here are serial pHt adjustable sensors (pTAS) that simply regulate the component ratio of second near‐infrared (NIR‐II) emission aza‐BODIPY (NAB) donor and pH sensitive rhodamine‐based pre‐acceptor (NRh) in Förster resonance energy transfer system. Combining the pH response regions of pTAS, a twofold widened pH detection range (6.11–7.22) is obtained compared to the pHt settled sensor (6.38–6.94). With an adjustable pHt, in vivo tumor pH increase and decrease processes could be dynamically visualized through dual‐channel ratiometric bioimaging within the NIR‐II window, with a coefficient of variation under 1 % compared to the standard pH meter. [ABSTRACT FROM AUTHOR]

Monitoring the pH in tumor lesions provides abundant physiological information. However, currently developed pH sensors only achieve sensitive detection in the settled response region around the pH transition point (pHt). To realize tumor pH monitoring with high sensitivity within a wider response region, reported here are serial pHt adjustable sensors (pTAS) that simply regulate the component ratio of second near‐infrared (NIR‐II) emission aza‐BODIPY (NAB) donor and pH sensitive rhodamine‐based pre‐acceptor (NRh) in Förster resonance energy transfer system. Combining the pH response regions of pTAS, a twofold widened pH detection range (6.11–7.22) is obtained compared to the pHt settled sensor (6.38–6.94). With an adjustable pHt, in vivo tumor pH increase and decrease processes could be dynamically visualized through dual‐channel ratiometric bioimaging within the NIR‐II window, with a coefficient of variation under 1 % compared to the standard pH meter. [ABSTRACT FROM AUTHOR]

In this paper, we give three pairs of complex 3-dim complete intersections and a pair of complex 5-dim complete intersections, and every pair of them is diffeomorphic but with different Hodge numbers. Moreover, the diffeomorphic complex 3-dim complete intersections have different Chern numbers c 1 3 , c 1 c 2. [ABSTRACT FROM AUTHOR]

• Bismuth selenide is used as a dielectric material to construct a sandwich structure. • The first infrared transparent conductive film in sandwich structure is developed. • Sandwich-structure film has better optoelectronic properties than bismuth selenide. Designing semiconductor/metal/semiconductor (SMS) sandwich structure film is an effective way to combine transparency and conductivity. However, traditional SMS mainly uses metal oxides such as ITO as the semiconductor material, which can only achieve transparency and conductivity in the visible to near-infrared band, but not in the mid-to far-infrared (MFIR) band. Here, we use bismuth selenide as semiconductor material and Ti as metal to construct SMS and achieve excellent MFIR transparent conductive properties. The results show that the conductivity of the SMS is increased by 3.8 times compared with the bismuth selenide, with only 3% decrease in the transmittance in 8–12 μm. Therefore, this study proposes a new material design strategy to solve the bottleneck problem of integrating MFIR transparency and conductivity. [ABSTRACT FROM AUTHOR]

Background: Familial progressive hyper- and hypopigmentation (FPHH, MIM 145250) is a rare hereditary skin disorder that is predominantly characterized by progressive, diffuse, partly blotchy hyperpigmented lesions intermingled with scattered hypopigmented spots, lentigines and sometimes Cafe-au-lait spots (CALs). Heterozygous mutations of the KIT ligand (KITLG, MIM 184745) gene are responsible for FPHH. To date, only eight KITLG mutations have been reported to be associated with FPHH, and no clear genotype–phenotype correlations have been established. This study aimed to identify the causative mutations in the KITLG gene in two Chinese FPHH patients. Methods: Direct sequencing of the coding regions of KITLG was performed. Pathogenicity prediction was performed using bioinformatics tools, including SIFT, Polyphen2, and SWISS-MODEL, and the results were further evaluated according to the 2015 American College of Medical Genetics and Genomics (ACMG) guidelines. Results: The novel mutation c.104A > T (p.Asn35Ile) and the recurrent mutation c.101C > T (p.Thr34Ile) in KITLG were identified. As shown using SIFT and Polyphen-2 software, both mutations identified in this study were predicted to be detrimental variations. Three-dimensional protein structure modeling indicated that the mutant KITLG proteins might affect the affinity of KITLG for its receptor, c-KIT. According to the 2015 ACMG guidelines, the novel mutation c.104A > T was 'likely pathogenic'. Conclusions: To date, most of the identified KITLG mutations have been clustered within the conserved VTNNV motif (amino acids 33–37) in exon 2. The known mutations are only involved in 33 V, 34 T, 36 N, and 37 V but not 35 N. We have now identified a novel mutation in KITLG, c.104A > T, that was first reported in FPHH within the conserved 35 N motif. These results strengthen our understanding of FPHH and expand the mutational spectrum of the KITLG gene. [ABSTRACT FROM AUTHOR]

Suspension systems are critical to the ride comfort and handling stability of vehicles, but traditional passive suspensions fail to achieve optimal performance in the two aspects. Semi‐active suspension controller changes the suspension stiffness or damping to improve the ride comfort and handling stability, which has the potential advantages of low energy consumption and high reliability. In this paper, the model of an air spring with an auxiliary chamber and a variable throttle orifice is proposed and the semi‐active control strategy of air suspension is carried out. The parameters of the air spring with auxiliary chamber are optimized to improve the performance when the control system fails and to increase the basic performance for semi‐active control. Based on the linear matrix inequality approach to robust H∞ control, the semi‐active control strategy of the air suspension is studied, in which parameter uncertainties and time delay are considered to improve control robustness. An inverse model of the air spring is then established to calculate the area of the variable throttle orifice, by which the desired control force is tracked accurately. Finally, the effectiveness of the semi‐active control system of the air suspension is verified by numerical simulation. Comparing with the passive suspension, not only under nominal parameters, but also with parameter uncertainties, time delay, and both parameter uncertainties and time delay, the semi‐active control system proposed in this paper has good control performance as well as is strong robustness to parameter uncertainties and time delay. [ABSTRACT FROM AUTHOR]

Sevoflurane is a widely used obstetric general anesthetic, but the neurotoxic effects of late-pregnancy exposure to one minimum alveolar concentration ([MAC], 2.5%) of sevoflurane on offspring remain unclear. We investigated whether exposure to 2.5% sevoflurane during late pregnancy would affect offspring hippocampal neuronal development and neurocognitive function. On gestational day 18 (G18), rats were randomly treated with 2.5% sevoflurane in 50% oxygen for 1 (Sev × 1), 3 (Sev × 3), or 6 h (Sev × 6). The neuronal apoptosis rate and mature brain-derived neurotrophic factor (mBDNF) and postsynaptic density protein 95 (PSD-95) expression levels were measured in offspring hippocampi on postnatal day 1 (P1) and P35. Dendritic spine formation and cognitive function were examined on P35. The neuronal apoptosis rate was enhanced, and mBDNF and PSD-95 levels were reduced in the Sev × 3 and Sev × 6 groups on P1. mBDNF and PSD-95 levels were also decreased in the Sev × 6 group on P35. The error rate was elevated in the maze test, whereas dendritic spine density and long-term potentiation (LTP) were reduced in the Sev × 6 group on P35. To determine whether exposure to an enriched environment (EE) would ameliorate sevoflurane's neurotoxic effects, offspring from another Sev × 6 group were exposed to either a standard environment (SE) or an EE. Lower error rates and greater dendritic spine densities and LTP were found in the Sev × 6 + EE vs. Sev × 6 + SE group. Collectively, we showed that exposing rats to 1 MAC sevoflurane for 3 h during late pregnancy increased neuronal apoptosis in neonates but did not impair neuronal development or cognitive function in juvenile rats, whereas a 6-h exposure impaired neuronal development and cognitive function in juvenile rats, effects that were attenuated by an EE. [ABSTRACT FROM AUTHOR]

A combined empirical mode decomposition (EMD) and multichannel singular spectrum analysis (MSSA) model (EMD–MSSA model) was used for extraction of the gravity tide correction without a priori information (e.g., station coordinates) from static relative gravimetric data. Static observational data acquired using a CG-5 relative gravimeter over 16 days were used to investigate the feasibility and reliability of the proposed method. The singular spectrum analysis (SSA) method and empirical mode decomposition (EMD)–independent component analysis (ICA) method were also adopted for comparison. Experimental results show that the time series of the gravity tide correction estimated using EMD–MSSA, SSA and EMD–ICA methods are consistent with a theoretical reference (the Longman formula). The gravity tide correction estimated using the EMD–MSSA method is closer to the theoretical model than other methods, the root-mean-square difference of the residuals between estimated values and theoretical values are smallest, and the accuracy of the gravity tide correction time series derived using the EMD–MSSA method is thus highest. The correlation coefficient of extraction results and GT is highest for the results extracted using the EMD–MSSA method. The experimental results show that using the EMD–MSSA model, which combines the advantages of the MSSA and EMD signal processing methods, improves the extraction estimation accuracy and reliability of the gravity tide correction from relative gravimetric data. [ABSTRACT FROM AUTHOR]

Shale gas reservoirs contain a large number of natural fractures. When shear slip occurs during hydraulic fracturing, it will increase reservoir permeability and improve the reservoir stimulation performance. Because shale contains a large amount of clay and organic matter, its shear slip behavior differs from that of other rocks. In this study, the shear behavior of different shale blocks is experimentally studied, and the proportion of clay and organic matter in the shale dominates the shear slip behavior. Specifically, the friction coefficient and shear strength decrease with the increasing content of clay and organic matter. A microscopic support model was developed to describe the different shear slip behaviors for different contents of clay and organic matter. When the clay and organic matter content is lower than a critical threshold (~35%), shale is microscopically grain supported and brittle shear occurs and the material is prone to shear dilation. When this content is greater than a critical content (~43%), the microscopic structure is a matrix‐supported fabric and plastic shear occurs, which is prone to shear contraction. Shale with contents between these two critical thresholds has a mixed‐support fabric, which is a transition type between brittle and plastic shear. If the proportion of clay and organic matter is less than ~35%, the natural fracture tends to dilate and retain a certain degree of opening after shearing, improving stimulation performance. When the proportion is more than ~43%, shear contraction occurs on the natural fracture surface, which is not conductive and cannot increase reservoir permeability. Key Points: Friction coefficient and shear strength decrease with increasing proportion of clay and organic matterDeveloped microscopic support model to describe different shear slip behaviors for different proportions of clay and organic matterLower clay content is easy to dilate after shear slip, thus improving reservoir permeability [ABSTRACT FROM AUTHOR]

Dynamic magnetic susceptibilities of high-aspect-ratio permalloylike nanorings (outer diameter 20 nm, inner diameter 12 nm, length (L) range 12–500 nm) are studied using three-dimensional micromagnetic simulations. The investigated systems show two major resonance modes associated with volume and shape resonance modes, corresponding to low and high resonance frequencies, respectively. When L is below 40 nm, only the shape resonance mode is seen with a frequency predicted using the Kittel’s equation and demagnetization factor calculated for a ring. At sufficiently large L, the frequency of the volume mode converges to that of the Kittel prediction. For other lengths, however, neither the low resonance frequency nor the high resonance frequency agrees with the Kittel’s equation. A weighted average resonance frequency fa(i) that contains two major modes is introduced and shows the same trend as the results predicted by the Kittel’s equation for all lengths. The frequencies of volume and shape resonance modes have also been investigated by changing the exchange stiffness constant (A) and the saturation magnetization (Ms). [ABSTRACT FROM AUTHOR]

The dynamic susceptibilities of permalloylike nanowires (20×500×20 nm3) have been investigated using the three-dimensional object oriented micromagnetic framework (OOMMF) code. The investigated systems show two resonant peaks associated with a “bulk” and an “edge” mode, which are attributed to the local effective field relevant to the local magnetic moments. A local analysis for ferromagnetic resonance calculation has been developed. It handles the local magnetic moments at the edge and the middle of the nanowire, respectively. The resonant frequencies of the edge mode are directly proportional to Ms or A under the same fundamental length scale, i.e., the exchange length. [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed cross-coupling reactions through metal carbene migratory insertion have emerged as powerful methodology for carbon–carbon bond constructions. Typically, diazo compounds (or in situ generated diazo compounds from N -tosylhydrazones) have been employed as the metal carbene precursors for this type of cross-coupling reactions. Recently, cross-coupling reactions employing non-diazo carbene precursors, such as conjugated ene-yne-ketones, allenyl ketones, alkynes, cyclopropenes, and Cr(0) Fischer carbenes, have been developed. This account will summarize our efforts in the development of transition-metal-catalyzed cross-coupling reactions with these non-diazo carbene precursors. 1 Introduction 2 Cross-Coupling with Ene-yne-ketones, Allenyl Ketones, and Alkynes 3 Cross-Coupling Involving Ring-Opening of Cyclopropenes 4 Palladium-Catalyzed Cross-Coupling with Chromium(0) Fischer Carbenes 5 Conclusion [ABSTRACT FROM AUTHOR]

This study was designed to test the hypothesis that nitrogen (N) addition leads to enhanced soil respiration (SR) in nitrogen deficient marsh. Here, we report the response of SR to simulated N deposition in a temperate marsh of northeastern China from June 2009 to September 2011. The experiment included three-levels of N treatment (control: no N addition, Low-N: 4g N m-2 y-1, and High-N: 8 g N m-2 y-1). Our study showed various responses of SR to level and duration of N addition. Yearly SR was increased by 11.8%-15.2% (P<0.05) under Low-N addition during the three years, while SR showed a strong increase by 27.5% (P<0.05) in the first year and then decreased by 4.4% (P>0.05) and 15.4% (P<0.05) in the next two years under High-N addition. Soil respiration was positively correlated with soil temperature and negatively correlated with soil water content. High-N treatment reduced soil pH value (P<0.05). The negative response of SR to High-N addition in the following two years may attribute to lower microbial activity, microbial biomass and alteration in the microbial community due to lower soil pH, which consequently leads to decreased SR. Meanwhile, we found root biomass were increased under High-N addition. This implies that the increase of autotrophic respiration was lower than the decline of heterotrophic respiration in the following two years. Our findings suggest complex interactions between N deposition and SR, which is needed to be further investigated in the future studies. [ABSTRACT FROM AUTHOR]

Cu(I)‐catalyzed reaction of diazo compounds generates a Cu(I)‐carbene intermediate that undergoes diverse transformations. In the past few years, the diazo compounds (or their precursor N‐tosylhydrazones) have been established as cross‐coupling partners under transition‐metal catalysis, affording various organic compounds. Particularly the breakthrough has been made in allene synthesis by Cu(I)‐catalyzed carbene coupling with terminal alkynes. Moreover, the Cu(I)‐catalyzed coupling reaction of diazo compounds with terminal alkynes generates allene intermediate that undergoes tandem cyclization/coupling to afford cyclic compounds. This review article summarizes the most recent developments in allene synthesis based on the Cu(I)‐carbene coupling reactions and the utilization of allene intermediates in tandem reactions. The allene syntheses based on the Cu(I)‐carbene coupling reactions and the utilization of allene intermediates in tandem reactions are summarized in this account. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Furans bearing alkynyl substituents are highly useful in organic synthesis. However, the methodologies to access these important furan derivatives are rather limited. We herein report an efficient synthesis of alkynylated furan derivatives based on Pd‐catalyzed oxidative cross‐coupling reaction between allenyl ketones and terminal alkynes. This novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional groups. Mechanistically, the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the transformation. The reaction reported in this paper further demonstrates the generality of the carbene‐based cross coupling. [ABSTRACT FROM AUTHOR]

We report two ratiometric fluorescent probes based on π-conjugation modulation between coumarin and hemicyanine moieties for sensitive ratiometric detection of pH alterations in live cells by monitoring visible and near-infrared fluorescence changes. In a π-conjugation modulation strategy, a coumarin dye was conjugated to a near-infrared hemicyanine dye via a vinyl connection while lysosome-targeting morpholine ligand and o-phenylenediamine residue were introduced to the hemicyanine moieties to form closed spirolactam ring structures in probes A and B , respectively. The probes show only visible fluorescence of the coumarin moiety under physiological and basic conditions because the hemicyanine moieties retain their closed spirolactam ring structures. However, decrease of pH to acidic condition causes spirolactam ring opening, and significantly enhances π-conjugation within the probes, thus generating new near-infrared fluorescence peaks of the hemicyanine at 755 nm and 740 nm for probes A and B , respectively. Moreover, the probes display ratiometric fluorescence response to pH with decreases of the coumarin fluorescence and increases of the hemicyanine fluorescence when pH changes from 7.4 to 2.5. The probes are fully capable of imaging pH changes in live cells with good ratiometric responses in visible and near-infrared channels, and effectively avoid fluorescence blind spots under neutral and basic pH conditions – an issue that typical intensity-based pH fluorescent probes run into. The probe design platform reported herein can be easily applied to prepare a variety of ratiometric fluorescent probes for detection of biological thiols, metal ions, reactive oxygen and nitrogen species by introducing appropriate functional groups to hemicyanine moiety. [ABSTRACT FROM AUTHOR]

The activity of glucagon-like peptide 1 (GLP-1R) is essential for preventing restenosis following vascular injury; however, the mechanism of dysfunctional GLP-1R glycosylation and ways to enhance the activity of GLP-1R on vascular surfaces in diabetic patients are poorly understood. In the present study, we investigated the N-glycosylation level and role of stress-associated endoplasmic reticulum protein 1 (SERP1) in preventing restenosis following carotid injury in diabetic rats. Our results showed that N-glycosylation levels in both rat aortic endothelial cells (RAOECs) and rat vascular smooth muscle cells (VSMCs) decreased gradually following glucose treatment in a concentration dependant manner. Furthermore, co-immunoprecipitation (Co-IP) analyses indicated that SERP1 could interact with GLP-1R in RAOECs and VSMCs. Moreover, SERP1 enhanced GLP-1R N-glycosylation and increased the production of phosphorylated endothelial nitric oxide synthase (eNOS) as well as proliferation of RAOECs. SERP1 also increased phosphorylated adenosine monophosphate activated protein kinase (AMPK) and decreased the migration of VSMCs. Importantly, intima media thickness (IMT) and neointimal hyperplasia were alleviated in the carotid artery of diabetic rats injected with SERP1 following balloon injury. We also found an increase in re-endothelialization and a decrease in VSMC proliferation in the carotid artery of diabetic rats injected with SERP1. In summary, the remarkable effects of SERP1 on reducing restenosis following vascular injury may contribute to future advancements in the treatment of diabetic vascular complications. [ABSTRACT FROM AUTHOR]

The mammalian heart is the first organ to form and is critical for embryonic survival and development. With an occurrence of 1%, congenital heart defects (CHDs) are also the most common birth defects in humans, and major cause of childhood morbidity and mortality (Hoffman and Kaplan in J Am Coll Cardiol 39(12):1890-1900, 2002; Samanek in Cardiol Young 10(3):179-185, 2000). Understanding how the heart forms will not only help to determine the etiology and to design diagnostic and therapeutic approaches for CHDs, but may also provide insight into regenerative medicine to repair injured adult hearts. Mammalian heart development requires precise orchestration of growth, differentiation, and morphogenesis to remodel a simple linear heart tube into an intricate, four-chambered heart with properly connected pulmonary artery and aorta, a structural basis for establishing the pulmonary and systemic circulation. Here we will review the recent advance in our understanding of how the planar cell polarity pathway, a highly conserved morphogenetic engine in vertebrates, regulates polarized morphogenetic processes to contribute to both the arterial and venous poles development of the heart. [ABSTRACT FROM AUTHOR]

Geminal bis(boron) compounds have recently emerged as valuable building blocks for the synthesis of molecules with structural diversity. They have advantages of unique stability, operational simplicity and can be engaged in several kinds of transformations. This review covers the synthetic methods of geminal bis(boron) compounds and their applications in organic synthesis. [ABSTRACT FROM AUTHOR]

Deflections of the vertical (DOVs) over oceans cannot be directly measured, which restricts their applications. A local covariance function of anomalous potential is put forward in this paper in conjunction with the least-squares collocation (LSC) method to compute the oceanic DOVs utilization of oceanic gravity data along a profile. The covariance functions of gravity field quantities have been derived directly as functions ofx,yandzwithout the need to introduce coordinate transformations corresponding to along- or cross-profile components. In the proposed methodology, gravity data along a profile were used to calculate the residual gravity anomaly using the remove-compute-restore technique. The residual gravity anomaly was used to calculate the parameters of the proposed covariance function of the local anomalous gravity field, which was used in the LSC to compute the residual DOVs along the profile. The residual DOVs added model DOVs to recover the DOVs along the profile. The results of a simulation experiment prove that the proposed methodology is feasible and effective. [ABSTRACT FROM PUBLISHER]

Explicit and implicit solvent effect are considered in the allene to furane reaction catalyzed by Au, Pt and Ru transition metals complexes. The catalyst restoration (picture) is different for the three metals. [Display omitted] • Three catalysts (AuCl, PtCl 2 , RuCl 2) are studied. • The theoretical study of the catalytic cycle unveils the complete mechanism. • Description of a two-step mechanism for the Pt catalyst's restoration. A furan catalytic synthesis from allene is studied with quantum chemistry computations. Both specific and non-specific solvent effect are considered. The complete catalytic cycle is studied for three metals, and compared to experimental data. The mechanism is disclosed and the catalyst regeneration shows clear difference between the three metals. For Pt, the regeneration corresponds to a two-steps mechanism with a stable intermediate. For Au and Ru catalysts the regeneration is a one step mechanism with a low barrier only for Au (3.8 kcal/mol). For Au, the results of the computations contrasts with the experiments, hence a poisoning of the catalyst is most likely. On the contrary, in the Ru case, the regeneration corresponds to the highest transition state of the cycle. [ABSTRACT FROM AUTHOR]

An aluminum electrolytic capacitor (AEC), mounted on a printed circuit board (PCB), is an integral part of any electronic product. Currently, a great many waste AECs are generated from almost all kinds of end-of-life electronic products. The waste AEC is hazardous waste because the electrolyte contained in it is toxic, demanding safe disposal. However, the recycling technology has been poorly developed. This article presented a novel attempt to deal with AECs disassembled from waste PCBs, including heat treatment, crushing, and multistage physical separations. Firstly, the electrolyte contained in waste AECs was removed by heat treatment. Secondly, the residue was crushed to liberate metals (aluminum and iron) from nonmetals, and the pins (iron) were magnetically separated from other substances. Thirdly, the remaining components were sieved, and the particles with the particle size >1.6 mm were subjected to eddy current separation, and the particles with the particle size <1.6 mm were subjected to electrostatic separation. Finally, an integrated recycling process was developed based on the above studies. Under the optimum conditions, the total separation efficiency and the grade of aluminum were 87.9% and 98.25%, respectively. This study provides a feasible method for waste AECs recycling in an efficient and environmentally way. [ABSTRACT FROM AUTHOR]

A new quinoline-based chemosensor ( CQ ) for sequential detection of Cu 2+ and CN − has been synthesized, where diaminomaleonitrile is introduced as recognition group. After addition of Cu 2+ , sensor CQ in aqueous solution (DMSO/H 2 O) displays remarkable colorimetric change from the light yellow to red, which is attributed to the extended intermolecular charge transfer in CQ -Cu 2+ complex. Sensor CQ shows a highly selective and sensitive response to Cu 2+ , which can be used as Test strips to conveniently monitor Cu 2+ . In addition, CQ -Cu 2+ complex could be applied to monitor sequentially cyanide anion with dramatic colour change based on copper ion complex displacement mechanism. [ABSTRACT FROM AUTHOR]

A new method is proposed to connect the orthometric height datum of island far from mainland with measurements of both ship-borne gravimetry and GNSS along the ship route connecting these datums. The methodology of route height datum connection is based on the astronomical leveling principle. The effect of the deflection of the vertical (DOV) error and the ellipsoidal height difference error are major factors on the precision of the orthometric height connection. To improve the computational accuracy of DOVs along the ship route, the collinear adjustment is used to improve the accuracy of the gravity measurements and GNSS ellipsoidal heights. The remove-restore technique in conjunction with the measured DOVs on the mainland and island is used to improve the estimation accuracy of the DOVs along the ship route. The least squares collocation method is used to estimate the residual DOVs. The covariance of gravity anomalies and cross-covariance function between gravity anomalies and DOVs are derived from the disturbing potential spherical harmonic expansion. The optimal partition number is also studied for the high precision orthometric height connection across sea. Finally, we use the proposed method to connect the orthometric height datum point on Qingdao coast in Shandong Province of China with the datum point on Caoyu coast in Fujian Province of China. [ABSTRACT FROM AUTHOR]

A new probe VC comprising coumarin as a fluorophore and a vinyl ether group as recognition unit is designed and synthesized. The key synthetic step is investigated by elimination reaction using 7-bromoethaneoxy-4-methylcoumarin with different bases. The probe VC shows almost no fluorescence in HEPES buffer (20 mM, pH 7.0), while displays obvious fluorescence enhancement after addition of Hg 2+ . Recognition mechanism is studied by NMR titration and MS, suggesting that the strongly fluorescent appearance is attributed to 7-hydroxy-4-methylcoumarin, the Hg 2+ -promoted hydrolysis reaction product. Due to the irreversible reaction and coumarin fluorescence property, the probe VC exhibits remarkable selectivity and sensitivity toward Hg 2+ (the detection limit is 0.12 μM). In addition, the detection experiment in real water sample reveals that probe VC could be used as a convenient tool to monitor Hg 2+ in neat aqueous solution by fluorescence turn-on response. [ABSTRACT FROM AUTHOR]

N-Tosylhydrazones have recently emerged as useful synthons in a variety of transition-metal-catalyzed and transition-metal-free reactions, which affords novel methodologies for the formation of carbon–carbon and carbon–heteroatom bonds. In this context, it has been found that N-tosylhydrazones can be used as versatile building blocks in the construction of a range of cyclic compounds. In this review, cyclization reactions based on N-tosylhydrazones as substrates are discussed. A series of cyclic compounds, including aromatic and non-aromatic ring systems, are demonstrated to be easily constructed by cyclizations with N-tosylhydrazones. [ABSTRACT FROM AUTHOR]

up to now, the recycling of e-waste should be developed towards more depth and refinement to promote industrial production of e-waste resource recovery. in the present study, the recycling of aluminum electrolytic capacitors (AECs) from waste printed circuit boards (WPCBs) is focused on. First of all, AECs are disassembled from WPCBs by a self-designed machine; meanwhile, the disassembled AECs are subjected to an integrated process, involving heating treatment, crushing, sieving, and magnetic separating, to recover aluminum and iron; finally, the off-gas and residue generated during the aforementioned processes are analyzed to evaluate environmental risks. The results indicate that 96.52% and 98.68% of aluminum and iron, respectively, can be recovered from AECs under the optimal condition. The off-gas generated during the process is mainly composed of elements of C, H, and O, indicating that the off-gas is non-toxic and could be re-utilized as clean energy source. The residue according with toxicity characteristics leaching standard can be landfilled safely in sanitary landfill site. The present study provides an environmentally friendly and industrial application potential strategy to recycle AECs to promote e-waste recycling industry. [ABSTRACT FROM AUTHOR]

A site-selective rhodium-catalyzed C−C activation of ring-fused cyclopentanones was achieved to afford efficient access to a range of spiroindanones. The use of bulky 2-amino-6-picoline as a cocatalyst is key to the excellent selectivity of this C−C bond cleavage in cyclopentanones. [ABSTRACT FROM AUTHOR]

A site-selective rhodium-catalyzed C−C activation of ring-fused cyclopentanones was achieved to afford efficient access to a range of spiroindanones. The use of bulky 2-amino-6-picoline as a cocatalyst is key to the excellent selectivity of this C−C bond cleavage in cyclopentanones. [ABSTRACT FROM AUTHOR]

In humans and other mammals, the neural retina does not spontaneously regenerate, and damage to the retina that kills retinal neurons results in permanent blindness. In contrast to embryonic stem cells, induced pluripotent stem cells, and embryonic/fetal retinal stem cells, Müller glia offer an intrinsic cellular source for regenerative strategies in the retina. Müller glia are radial glial cells within the retina that maintain retinal homeostasis, buffer ion flux associated with phototransduction, and form the blood/retinal barrier within the retina proper. In injured or degenerating retinas, Müller glia contribute to gliotic responses and scar formation but also show regenerative capabilities that vary across species. In the mammalian retina, regenerative responses achieved to date remain insufficient for potential clinical applications. Activation of JAK/STAT and MAPK signaling by CNTF, EGF, and FGFs can promote proliferation and modulate the glial/neurogenic switch. However, to achieve clinical relevance, additional intrinsic and extrinsic factors that restrict or promote regenerative responses of Müller glia in the mammalian retina must be identified. This review focuses on Müller glia and Müller glial-derived stem cells in the retina and phylogenetic differences among model vertebrate species and highlights some of the current progress towards understanding the cellular mechanisms regulating their regenerative response. [ABSTRACT FROM AUTHOR]

• The mesoporous iron oxide was successfully synthesized by using the waste wood powder as a template. • The alkali concentration had an effect on the physicochemical properties and performance of the synthesized iron oxides. • The iron oxide catalyst with larger surface area and pore volume exhibited higher yield of gasoline and diesel distillates. • The perfect performance of mesoporous iron oxide catalyst is ascribed to the presence of more exposure Fe active sites. In order to develop a high-efficiency iron oxide catalyst for the slurry-phase hydrocracking of poor heavy oil, the mesoporous iron oxide was successfully synthesized by using the waste wood powder as a template, and the influence of alkali concentration in the resulting solution on crystal phase, morphology and pore structure of the synthesized samples was investigated. The crystal phase of the synthesized iron oxide transfers from α-Fe 2 O 3 to γ-Fe 2 O 3 , and their crystal sizes gradually decrease with an increase of alkali concentration based on the XRD and HRTEM results. Additionally, the iron oxide with mesoporous structure, larger surface area and pore volume is obtained at the higher concentration of alkali in solution confirmed by N 2 adsorption-desorption analysis. The assessment result of the iron oxide catalyst employed in the slurry-phase hydrocracking of vacuum residue (VR) illustrates that the yields of gasoline and diesel distillates obtained over Fe-O-B 20 , Fe-O-B 24 and Fe-O-B 30 catalysts are higher compared with those over Fe-O-B 2 and Fe-O-B 14 catalysts, it can be attributed that more exposure Fe active sites derived from their larger surface area and pore volume availably improve the catalyst hydrogenation activity, which can inhibit the over-cracking reaction of intermediate products and the condensation of polycyclic aromatic hydrocarbon in VR to enhance the yields of gasoline and diesel distillates. [ABSTRACT FROM AUTHOR]