We report a detailed study of magnetically levitated loading of ultracold ^(133)Cs atoms in a dimple trap.The atomic sample was produced in a combined red-detuned optical dipole trap and dimple trap formed by two smal...We report a detailed study of magnetically levitated loading of ultracold ^(133)Cs atoms in a dimple trap.The atomic sample was produced in a combined red-detuned optical dipole trap and dimple trap formed by two small waist beams crossing a horizontal plane.The magnetic levitation for the ^(133)Cs atoms forms an effective potential for a large number of atoms in a high spatial density.Dependence of the number of atoms loaded and trapped in the dimple trap on the magnetic field gradient and bias field is in good agreement with the theoretical analysis.This method has been widely used to obtain the Bose–Einstein condensation atoms for many atomic species.展开更多
Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enha...Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enhanced biological phosphorus removal(EBPR).However,it is unclear how Tetrasphaera PAOs are selectively enriched in the context of the EBPR microbiome.In this study,an EBPR microbiome enriched with Tetrasphaera(accounting for 40%of 16S sequences on day 113)was built using a top-down design approach featuring multicarbon sources and a low dosage of allylthiourea.The microbiome showed enhanced nutrient removal(phosphorus removal~85%and nitrogen removal~80%)and increased phosphorus recovery(up to 23.2 times)compared with the seeding activated sludge from a local full-scale WWTP.The supply of 1 mg·L^(-1)allylthiourea promoted the coselection of Tetrasphaera PAOs and Microlunatus PAOs and sharply reduced the relative abundance of both ammonia oxidizer Nitrosomonas and putative competitors Brevundimonas and Paracoccus,facilitating the establishment of the EBPR microbiome.Based on 16S rRNA gene analysis,a putative novel PAO species,EBPR-ASV0001,was identified with Tetrasphaera japonica as its closest relative.This study provides new knowledge on the establishment of a Tetrasphaera-enriched microbiome facilitated by allylthiourea,which can be further exploited to guide future process upgrading and optimization to achieve and/or enhance simultaneous biological phosphorus and nitrogen removal from high-strength wastewater.展开更多
A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA)....A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA). Interestingly, Mn_(2)Cu_(1)O_(x)exhibited an excellent furfural conversion of 99% with quantitative selectivity toward FA. Especially, we demonstrate the significant weakening of the Mn-O bonds with the incorporation of CuO into the Mn-Cu oxides, resulting in an improved OLreactivity of Mn_(2)Cu_(1)O_(x), which brings about a higher catalytic activity for furfural oxidation. More importantly, Mn_(2)Cu_(1)O_(x)could exhibit YFA>90% over 5 cycles of reusability test. Through this study, the relationship between the morphology, surface chemistry, and catalytic activity of Mn-Cu bimetallic oxides are elucidated, providing a simple and environmentally friendly catalytic strategy and scientific basis for the development of Mn-Cu bimetallic oxides bioderived molecular aerobic oxidation materials.展开更多
Extreme weather events and climate change have witnessed a substantial increase in recent years,leading to heightened concerns.The rise in abnormal ambient temperatures,both in intensity and frequency,directly and ind...Extreme weather events and climate change have witnessed a substantial increase in recent years,leading to heightened concerns.The rise in abnormal ambient temperatures,both in intensity and frequency,directly and indirectly impacts cardiovascular health.While the impact of high ambient temperatures on cardiovascular response is a common concern in the context of global warming,the significance of low temperatures cannot be overlooked.The challenges posed by low temperatures contribute to increased cardiovascular morbidity and mortality,posing a significant threat to global public health.This review aims to provide an overview of the relationship between low ambient temperature and cardiovascular health,encompassing the burden of cardiovascular outcomes and underlying mechanisms.Additionally,the review explores strategies for cold adaptation and cardioprotection.We posit that to optimize cold adaptation strategies,future research should delve deeper into the underlying mechanisms of cardiovascular health in response to low ambient temperature exposure.展开更多
In this paper, we first transferred the normal height of ASTER GDEM v2 to GPS ellipsoidal height based on the EGM96, and analyzed the precision of this digital elevation model in the northeastern margin of Tibetan Pla...In this paper, we first transferred the normal height of ASTER GDEM v2 to GPS ellipsoidal height based on the EGM96, and analyzed the precision of this digital elevation model in the northeastern margin of Tibetan Plateau (NETP) combining with 89 ground GPS measurements. The results demonstrate that the standard deviation of the difference between ASTER GDEM and GPS results is 9.3 m, and the precision of ASTER GDEM in this region is approximately 10 m. We also calculated the free-air gravity anomalies using the relative gravity data and DEM model in NETP. The results show that the gravity anomalies are generally negative with local positive values, ranging from -156 to 43 reGal (10-5 m/s2). At last, we compared the EGM2008 free-air gravity anomalies (FGAs) with the ground gravity measurements, and their spatial patterns are similar. While the point-to-point difference between the modeling and measuring results shows great discrepancy. The free-air gravity anomalies of EGM2008 in this region range from -154 to 96 mGal, and the difference between EGM2008 and the ground measurements ranges from -102 to 50 regal. The mean difference is -17.34 mGal, and the standard deviation is 46.69 mGal, which demonstrates that the EGM2008 has poor precision in the northeastern margin of Tibet Plateau.展开更多
Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and ene...Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(<em>μ</em><sub>2</sub>-2-methylimidazolyl)<sub>12</sub>-Zn(ii)<sub>6</sub>-H<sub>18</sub>O<sub>10</sub>]<sub>n</sub>(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m<sup>2</sup><span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, and the pore size structure was mainly mesoporous. At a current density of 1.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> and 226.6 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, with a decay rate of 25.5%, when the current density increases to 10.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising.展开更多
In order to study the relationship between gravity variation and Menyuan Ms6.4 earth- quake, gravity variation characteristics in mid-eastern of Qilian Mountain were analyzed based on the 2012-2015 relative gravity da...In order to study the relationship between gravity variation and Menyuan Ms6.4 earth- quake, gravity variation characteristics in mid-eastern of Qilian Mountain were analyzed based on the 2012-2015 relative gravity datasets. The results indicated that the gravity changes in mid-eastern of Qilian Mountain increased gradually, while gravity changes around Menyuan remarkably. Besides, great positive-negative gravity changing gradients appeared along the Lengiongling Fault which was located at the north of Menyuan, and the 2016 Menyuan Ms6.4 earthquake occurred near the junction of positive and negative gravity changes.展开更多
After the Wenchuan earthquake in 2008,China Earthquake Administration has strengthened the monitoring of mobile gravity and earthquake forecasting.This paper mainly analyzes the development of mobile gravity monitorin...After the Wenchuan earthquake in 2008,China Earthquake Administration has strengthened the monitoring of mobile gravity and earthquake forecasting.This paper mainly analyzes the development of mobile gravity monitoring network of China in 2008,the role of time-varying gravity field in the determination of strong earthquake risk and the technical problems that gravity monitoring still needs to be solved.By analysing the mobile gravity monitoring and earthquake prediction in China,the characteristics of gravity anomaly and three elements of earthquake prediction are discussed.The mobile gravity observation data can better reflect the gravity anomalies before the earthquake,especially the strong earthquakes greater than Ms6.0.Finally,we put forward the reconsideration of the development strategy of mobile gravity monitoring and earthquake forecasting in China.展开更多
In this study, the relative gravity data(2012 e2015), GPS data-derived horizontal deformation(2011 e2014) and the background vertical deformation from the leveling measurements(1970 e2011) in the northeastern margin o...In this study, the relative gravity data(2012 e2015), GPS data-derived horizontal deformation(2011 e2014) and the background vertical deformation from the leveling measurements(1970 e2011) in the northeastern margin of Tibetan Plateau were processed to systematically analysis the mechanism of temporalespatial patterns and the relationship with Menyuan Ms6.4 earthquake. It can be summarized in the following: 1) The regional gravity changes, the GPS and the vertical deformational showed an intense spatial relationship: the gravity increased along with the direction of horizontal movement, and decreased with the crustal uplift and vice versa, which reflected the inherited characteristics of geotectonic activities. 2) The crustal deformations were closely related to the active faults. The contour lines of gravity changes and vertical deformation were generally along with the Qilian-Haiyuan fault(strike is NWW), and the crustal horizontal deformation showed left-lateral strike slip motion near the Qilian-Haiyuan fault. 3) Menyuan Ms6.4 earthquake occurred in the high negative gravity variation area and a high gradient formed in regions, positive and negative variation of gravity amount to 110 m Gal.Specifically, a borderline of positive and negative gravity located in the south of epicenter along the north edge of Qilianshan fault and Lenglongling fault, as well as the vertical and/or horizontal deformation is intensely. The extrusion deformation, surface compression rate and gravity changes were obvious near the epicenter of 2016 Menyuan Earthquake.展开更多
The hot deformation characteristics of as-cast nickel-base superalloy GH742y after hot isostatic pressing (HIP)(hereafter referred to as-cast alloy) have been investigated by hot compression tests in the temperatu...The hot deformation characteristics of as-cast nickel-base superalloy GH742y after hot isostatic pressing (HIP)(hereafter referred to as-cast alloy) have been investigated by hot compression tests in the temperature range of 1050 to 1140℃, strain rate range of 0.01 s^-1 to 10 s^-1 and strain range of 35% to 50% by means of Gleeble-3500 thermal mechanical simulator. The results show that the as-cast alloy exhibits the poor deformability, and shows wedge-shaped cracking beyond the strain of 35%. At strain rates less than 1.0 s^-1, the stress-strain curves exhibit nearly steady-state behavior, while at strain rate of 10 s^-1, a yield drop and serrated yielding occur. The activation energy values developed on the basis of the experimental data are divided into three domains. The first domain appears at lower strain rate (≤1.0 s^-1) and lower temperature (≤1080℃), with the lowest mean value of activation energy about 261.4 kJ/mol. The second domain appears at the same strain rate as the first domain, but higher temperature (〉1080℃), with the intermediate mean value of activation energy about 328.8 k J/tool. The third domain appears at higher strain rate (10 s^-1) and temperature range of 1050 to 1140℃, with the largest mean value of activation energy about 605.05 kJ/mol. Three different constitutive equations are established in corresponding to domains. Microstructural observations in the third domain reveal non-uniform dynamic recrystallization (DRX) of homogeneous γ phase, which leads to the poor deformability and the highest Q value. In contrast, microstructures in the first domain show fully DRX of homogeneous γ phase, leading to the better deformability and the lowest Q value. It is noted that the grain size increases with the increment of strain rate or temperature. These results suggest that bulk metal working of this material may be carried out in the first domain where fully DRX of γ homogeneous occurred.展开更多
The multispectral remote sensing image(MS-RSI)is degraded existing multi-spectral camera due to various hardware limitations.In this paper,we propose a novel core tensor dictionary learning approach with the robust mo...The multispectral remote sensing image(MS-RSI)is degraded existing multi-spectral camera due to various hardware limitations.In this paper,we propose a novel core tensor dictionary learning approach with the robust modified Gaussian mixture model for MS-RSI restoration.First,the multispectral patch is modeled by three-order tensor and high-order singular value decomposition is applied to the tensor.Then the task of MS-RSI restoration is formulated as a minimum sparse core tensor estimation problem.To improve the accuracy of core tensor coding,the core tensor estimation based on the robust modified Gaussian mixture model is introduced into the proposed model by exploiting the sparse distribution prior in image.When applied to MS-RSI restoration,our experimental results have shown that the proposed algorithm can better reconstruct the sharpness of the image textures and can outperform several existing state-of-the-art multispectral image restoration methods in both subjective image quality and visual perception.展开更多
Most of previous video recording devices in mobile vehicles commonly store captured video contents locally. With the rapid development of 4G/Wi Fi networks, there emerges a new trend to equip video recording devices w...Most of previous video recording devices in mobile vehicles commonly store captured video contents locally. With the rapid development of 4G/Wi Fi networks, there emerges a new trend to equip video recording devices with wireless interfaces to enable video uploading to the cloud for video playback in a later time point. In this paper, we propose a QoE-aware mobile cloud video recording scheme in the roadside vehicular networks, which can adaptively select the proper wireless interface and video bitrate for video uploading to the cloud. To maximize the total utility, we need to design a control strategy to carefully balance the transmission cost and the achieved QoE for users. To this purpose, we investigate the tradeoff between cost incurred by uploading through cellular networks and the achieved QoE of users. We apply the optimization framework to solve the formulated problem and design an online scheduling algorithm. We also conduct extensive trace-driven simulations and our results show that our algorithm achieves a good balance between the transmission cost and user QoE.展开更多
Image super resolution is an important field of computer research.The current mainstream image super-resolution technology is to use deep learning to mine the deeper features of the image,and then use it for image res...Image super resolution is an important field of computer research.The current mainstream image super-resolution technology is to use deep learning to mine the deeper features of the image,and then use it for image restoration.However,most of these models mentioned above only trained the images in a specific scale and do not consider the relationships between different scales of images.In order to utilize the information of images at different scales,we design a cascade network structure and cascaded super-resolution convolutional neural networks.This network contains three cascaded FSRCNNs.Due to each sub FSRCNN can process a specific scale image,our network can simultaneously exploit three scale images,and can also use the information of three different scales of images.Experiments on multiple datasets confirmed that the proposed network can achieve better performance for image SR.展开更多
The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic...The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic and gravimetric data, skeleton seismic profiles, magnetotelluric profiles and drilling data. Here, we present gravimetric and magnetic data analyses of the basement structures of the Tacheng basin and its base formation. We also provide a magnetotelluric profile analysis of the structural features and tectonic framework of basin-mountain patterns. We use local geology, drilling data, and other comprehensive information to document the tectonic framework of the basement of the basin. Small-scale nappe structures are found in the northern basin, whereas stronger and more pronounced thrusting structures are found to the south and east of the basin. The basin is divided into four first-order tectonic units: a central uplift, a northern depression, a southeastern depression and a western depression. In addition, the Emin sag is suggested as a possible reservoir for oil and gas.展开更多
DEAR EDITOR,The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a tremendous threat to human society. SARS-CoV-2is airborne and transmits primarily through social contact;however, whether cold chain-related t...DEAR EDITOR,The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a tremendous threat to human society. SARS-CoV-2is airborne and transmits primarily through social contact;however, whether cold chain-related transmission has occurred remains highly debated(Han & Liu, 2022;Lewis,2021;Ma et al., 2021;Mallapaty et al., 2021;Pang et al.,2020;Wu et al., 2021). Here, we present a novel method and identify two transmission routes based on lineage-specific reductions in the SARS-CoV-2 evolutionary rate.展开更多
The composite films consisting of the titania gel impregnated with hydroxyapatite (HAP) submicron particles were prepared on commercial Ti6A14V plates processed by a sol-gel route. HAP powders were synthesized based...The composite films consisting of the titania gel impregnated with hydroxyapatite (HAP) submicron particles were prepared on commercial Ti6A14V plates processed by a sol-gel route. HAP powders were synthesized based on wet chemical precipitation method with Ca(NO3)2.4H2O and (NH4)2HPO4 as starting reagents. After being calcined at 900℃, HAP powders were ultrasonically scattered in ethanol to produce HAP sol. The titania sol was prepared using titanium (IV) isopropoxide {Ti[OCH(CH3)2]4} as precursor. Both the titania sol and the HAP/titania mixture were sequentially spin-coated on the substrates and calcined at various temperatures. The characteristics and mechanical adhesion of the composite films were investigated. The results show that the as-prepared films are dense, homogeneous, well-crystallized, and there is a good interfacial adhesion between the film and the substrate. The in vitro bioactivities of these films were discussed based on the analysis of the variations of Ca and P concentrations in the simulated body fluid and their surface morphologies against immersion time.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.62020106014,62175140,12034012,and 92165106)the Natural Science Young Foundation of Shanxi Province(Grant No.202203021212376).
文摘We report a detailed study of magnetically levitated loading of ultracold ^(133)Cs atoms in a dimple trap.The atomic sample was produced in a combined red-detuned optical dipole trap and dimple trap formed by two small waist beams crossing a horizontal plane.The magnetic levitation for the ^(133)Cs atoms forms an effective potential for a large number of atoms in a high spatial density.Dependence of the number of atoms loaded and trapped in the dimple trap on the magnetic field gradient and bias field is in good agreement with the theoretical analysis.This method has been widely used to obtain the Bose–Einstein condensation atoms for many atomic species.
基金supported by the Key Research and Development Program of Zhejiang(2022C03075)National Natural Science Foundation of China(22241603)Zhejiang Provincial Natural Science Foundation of China(LR22D010001)。
文摘Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enhanced biological phosphorus removal(EBPR).However,it is unclear how Tetrasphaera PAOs are selectively enriched in the context of the EBPR microbiome.In this study,an EBPR microbiome enriched with Tetrasphaera(accounting for 40%of 16S sequences on day 113)was built using a top-down design approach featuring multicarbon sources and a low dosage of allylthiourea.The microbiome showed enhanced nutrient removal(phosphorus removal~85%and nitrogen removal~80%)and increased phosphorus recovery(up to 23.2 times)compared with the seeding activated sludge from a local full-scale WWTP.The supply of 1 mg·L^(-1)allylthiourea promoted the coselection of Tetrasphaera PAOs and Microlunatus PAOs and sharply reduced the relative abundance of both ammonia oxidizer Nitrosomonas and putative competitors Brevundimonas and Paracoccus,facilitating the establishment of the EBPR microbiome.Based on 16S rRNA gene analysis,a putative novel PAO species,EBPR-ASV0001,was identified with Tetrasphaera japonica as its closest relative.This study provides new knowledge on the establishment of a Tetrasphaera-enriched microbiome facilitated by allylthiourea,which can be further exploited to guide future process upgrading and optimization to achieve and/or enhance simultaneous biological phosphorus and nitrogen removal from high-strength wastewater.
基金supported by the National Natural Science Fund of China (Nos. 21978246 and 21776234)。
文摘A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA). Interestingly, Mn_(2)Cu_(1)O_(x)exhibited an excellent furfural conversion of 99% with quantitative selectivity toward FA. Especially, we demonstrate the significant weakening of the Mn-O bonds with the incorporation of CuO into the Mn-Cu oxides, resulting in an improved OLreactivity of Mn_(2)Cu_(1)O_(x), which brings about a higher catalytic activity for furfural oxidation. More importantly, Mn_(2)Cu_(1)O_(x)could exhibit YFA>90% over 5 cycles of reusability test. Through this study, the relationship between the morphology, surface chemistry, and catalytic activity of Mn-Cu bimetallic oxides are elucidated, providing a simple and environmentally friendly catalytic strategy and scientific basis for the development of Mn-Cu bimetallic oxides bioderived molecular aerobic oxidation materials.
基金supported by the National Natural Science Foundation of China(grant#81973001)the Zhejiang Chinese Medical University Startup Fund.
文摘Extreme weather events and climate change have witnessed a substantial increase in recent years,leading to heightened concerns.The rise in abnormal ambient temperatures,both in intensity and frequency,directly and indirectly impacts cardiovascular health.While the impact of high ambient temperatures on cardiovascular response is a common concern in the context of global warming,the significance of low temperatures cannot be overlooked.The challenges posed by low temperatures contribute to increased cardiovascular morbidity and mortality,posing a significant threat to global public health.This review aims to provide an overview of the relationship between low ambient temperature and cardiovascular health,encompassing the burden of cardiovascular outcomes and underlying mechanisms.Additionally,the review explores strategies for cold adaptation and cardioprotection.We posit that to optimize cold adaptation strategies,future research should delve deeper into the underlying mechanisms of cardiovascular health in response to low ambient temperature exposure.
基金supported by NSFCs (grant Nos. 61627824, 41274083, 41174011, 41429401, 41210006, 41128003, 41021061)National 973 Project China (grant Nos. 2013CB733302 and 2013CB733305)
文摘In this paper, we first transferred the normal height of ASTER GDEM v2 to GPS ellipsoidal height based on the EGM96, and analyzed the precision of this digital elevation model in the northeastern margin of Tibetan Plateau (NETP) combining with 89 ground GPS measurements. The results demonstrate that the standard deviation of the difference between ASTER GDEM and GPS results is 9.3 m, and the precision of ASTER GDEM in this region is approximately 10 m. We also calculated the free-air gravity anomalies using the relative gravity data and DEM model in NETP. The results show that the gravity anomalies are generally negative with local positive values, ranging from -156 to 43 reGal (10-5 m/s2). At last, we compared the EGM2008 free-air gravity anomalies (FGAs) with the ground gravity measurements, and their spatial patterns are similar. While the point-to-point difference between the modeling and measuring results shows great discrepancy. The free-air gravity anomalies of EGM2008 in this region range from -154 to 96 mGal, and the difference between EGM2008 and the ground measurements ranges from -102 to 50 regal. The mean difference is -17.34 mGal, and the standard deviation is 46.69 mGal, which demonstrates that the EGM2008 has poor precision in the northeastern margin of Tibet Plateau.
文摘Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(<em>μ</em><sub>2</sub>-2-methylimidazolyl)<sub>12</sub>-Zn(ii)<sub>6</sub>-H<sub>18</sub>O<sub>10</sub>]<sub>n</sub>(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m<sup>2</sup><span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, and the pore size structure was mainly mesoporous. At a current density of 1.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup> and 226.6 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>, with a decay rate of 25.5%, when the current density increases to 10.0 A<span style="white-space:nowrap;">⋅</span>g<sup><span style="white-space:nowrap;">−</span>1</sup>. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising.
基金funded by the directional earthquake tracking task offered by China Earthquake Administration(2016020213)
文摘In order to study the relationship between gravity variation and Menyuan Ms6.4 earth- quake, gravity variation characteristics in mid-eastern of Qilian Mountain were analyzed based on the 2012-2015 relative gravity datasets. The results indicated that the gravity changes in mid-eastern of Qilian Mountain increased gradually, while gravity changes around Menyuan remarkably. Besides, great positive-negative gravity changing gradients appeared along the Lengiongling Fault which was located at the north of Menyuan, and the 2016 Menyuan Ms6.4 earthquake occurred near the junction of positive and negative gravity changes.
基金funded by the National Science Foundation of China (41874092, 61627824)
文摘After the Wenchuan earthquake in 2008,China Earthquake Administration has strengthened the monitoring of mobile gravity and earthquake forecasting.This paper mainly analyzes the development of mobile gravity monitoring network of China in 2008,the role of time-varying gravity field in the determination of strong earthquake risk and the technical problems that gravity monitoring still needs to be solved.By analysing the mobile gravity monitoring and earthquake prediction in China,the characteristics of gravity anomaly and three elements of earthquake prediction are discussed.The mobile gravity observation data can better reflect the gravity anomalies before the earthquake,especially the strong earthquakes greater than Ms6.0.Finally,we put forward the reconsideration of the development strategy of mobile gravity monitoring and earthquake forecasting in China.
基金funded by the directional earthquake tracking task offered by China Earthquake Administration (2017010203)the National Natural Science Foundation of China (No. 41274083)
文摘In this study, the relative gravity data(2012 e2015), GPS data-derived horizontal deformation(2011 e2014) and the background vertical deformation from the leveling measurements(1970 e2011) in the northeastern margin of Tibetan Plateau were processed to systematically analysis the mechanism of temporalespatial patterns and the relationship with Menyuan Ms6.4 earthquake. It can be summarized in the following: 1) The regional gravity changes, the GPS and the vertical deformational showed an intense spatial relationship: the gravity increased along with the direction of horizontal movement, and decreased with the crustal uplift and vice versa, which reflected the inherited characteristics of geotectonic activities. 2) The crustal deformations were closely related to the active faults. The contour lines of gravity changes and vertical deformation were generally along with the Qilian-Haiyuan fault(strike is NWW), and the crustal horizontal deformation showed left-lateral strike slip motion near the Qilian-Haiyuan fault. 3) Menyuan Ms6.4 earthquake occurred in the high negative gravity variation area and a high gradient formed in regions, positive and negative variation of gravity amount to 110 m Gal.Specifically, a borderline of positive and negative gravity located in the south of epicenter along the north edge of Qilianshan fault and Lenglongling fault, as well as the vertical and/or horizontal deformation is intensely. The extrusion deformation, surface compression rate and gravity changes were obvious near the epicenter of 2016 Menyuan Earthquake.
文摘The hot deformation characteristics of as-cast nickel-base superalloy GH742y after hot isostatic pressing (HIP)(hereafter referred to as-cast alloy) have been investigated by hot compression tests in the temperature range of 1050 to 1140℃, strain rate range of 0.01 s^-1 to 10 s^-1 and strain range of 35% to 50% by means of Gleeble-3500 thermal mechanical simulator. The results show that the as-cast alloy exhibits the poor deformability, and shows wedge-shaped cracking beyond the strain of 35%. At strain rates less than 1.0 s^-1, the stress-strain curves exhibit nearly steady-state behavior, while at strain rate of 10 s^-1, a yield drop and serrated yielding occur. The activation energy values developed on the basis of the experimental data are divided into three domains. The first domain appears at lower strain rate (≤1.0 s^-1) and lower temperature (≤1080℃), with the lowest mean value of activation energy about 261.4 kJ/mol. The second domain appears at the same strain rate as the first domain, but higher temperature (〉1080℃), with the intermediate mean value of activation energy about 328.8 k J/tool. The third domain appears at higher strain rate (10 s^-1) and temperature range of 1050 to 1140℃, with the largest mean value of activation energy about 605.05 kJ/mol. Three different constitutive equations are established in corresponding to domains. Microstructural observations in the third domain reveal non-uniform dynamic recrystallization (DRX) of homogeneous γ phase, which leads to the poor deformability and the highest Q value. In contrast, microstructures in the first domain show fully DRX of homogeneous γ phase, leading to the better deformability and the lowest Q value. It is noted that the grain size increases with the increment of strain rate or temperature. These results suggest that bulk metal working of this material may be carried out in the first domain where fully DRX of γ homogeneous occurred.
基金This work was supported by the Project of Shandong Province Higher Educational Science and Technology Program[KJ2018BAN047,Geng,L.]National Natural Science Foundation of China[61801222,Fu,P.]+2 种基金Fundamental Research Funds for the Central Universities[30919011230,Fu,P.]Science and Technology Innovation Program for Distributed Young Talents of Shandong Province Higher Education Institutions[2019KJN045,Guo,Q.]Shandong Provincial Key Laboratory of Network Based Intelligent Computing[http://nbic.ujn.edu.cn/].
文摘The multispectral remote sensing image(MS-RSI)is degraded existing multi-spectral camera due to various hardware limitations.In this paper,we propose a novel core tensor dictionary learning approach with the robust modified Gaussian mixture model for MS-RSI restoration.First,the multispectral patch is modeled by three-order tensor and high-order singular value decomposition is applied to the tensor.Then the task of MS-RSI restoration is formulated as a minimum sparse core tensor estimation problem.To improve the accuracy of core tensor coding,the core tensor estimation based on the robust modified Gaussian mixture model is introduced into the proposed model by exploiting the sparse distribution prior in image.When applied to MS-RSI restoration,our experimental results have shown that the proposed algorithm can better reconstruct the sharpness of the image textures and can outperform several existing state-of-the-art multispectral image restoration methods in both subjective image quality and visual perception.
基金supported in part by the National Science Foundation of China under Grant 61272397,Grant 61572538,Grant 61174152,Grant 61331008in part by the Guangdong Natural Science Funds for Distinguished Young Scholar under Grant S20120011187
文摘Most of previous video recording devices in mobile vehicles commonly store captured video contents locally. With the rapid development of 4G/Wi Fi networks, there emerges a new trend to equip video recording devices with wireless interfaces to enable video uploading to the cloud for video playback in a later time point. In this paper, we propose a QoE-aware mobile cloud video recording scheme in the roadside vehicular networks, which can adaptively select the proper wireless interface and video bitrate for video uploading to the cloud. To maximize the total utility, we need to design a control strategy to carefully balance the transmission cost and the achieved QoE for users. To this purpose, we investigate the tradeoff between cost incurred by uploading through cellular networks and the achieved QoE of users. We apply the optimization framework to solve the formulated problem and design an online scheduling algorithm. We also conduct extensive trace-driven simulations and our results show that our algorithm achieves a good balance between the transmission cost and user QoE.
基金supported in part by the National Natural Science Foundation of China under Grant 61806099in part by the Natural Science Foundation of Jiangsu Province of China under Grant BK20180790,in part by the Natural Science Research of Jiangsu Higher Education Institutions of China under Grant 8KJB520033in part by Startup Foundation for Introducing Talent of Nanjing University of Information Science and Technology under Grant 2243141701077.
文摘Image super resolution is an important field of computer research.The current mainstream image super-resolution technology is to use deep learning to mine the deeper features of the image,and then use it for image restoration.However,most of these models mentioned above only trained the images in a specific scale and do not consider the relationships between different scales of images.In order to utilize the information of images at different scales,we design a cascade network structure and cascaded super-resolution convolutional neural networks.This network contains three cascaded FSRCNNs.Due to each sub FSRCNN can process a specific scale image,our network can simultaneously exploit three scale images,and can also use the information of three different scales of images.Experiments on multiple datasets confirmed that the proposed network can achieve better performance for image SR.
文摘The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic and gravimetric data, skeleton seismic profiles, magnetotelluric profiles and drilling data. Here, we present gravimetric and magnetic data analyses of the basement structures of the Tacheng basin and its base formation. We also provide a magnetotelluric profile analysis of the structural features and tectonic framework of basin-mountain patterns. We use local geology, drilling data, and other comprehensive information to document the tectonic framework of the basement of the basin. Small-scale nappe structures are found in the northern basin, whereas stronger and more pronounced thrusting structures are found to the south and east of the basin. The basin is divided into four first-order tectonic units: a central uplift, a northern depression, a southeastern depression and a western depression. In addition, the Emin sag is suggested as a possible reservoir for oil and gas.
基金supported by the National Key Research and Development Project (2020YFC0847000,2021YFC0863300, 2020YFC0845900)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDPB17)+1 种基金the National Natural Science Foundation of China (31100273, 91731304,31172073)Shandong Academician Workstation Program#170401 (to G.P.Z.)。
文摘DEAR EDITOR,The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a tremendous threat to human society. SARS-CoV-2is airborne and transmits primarily through social contact;however, whether cold chain-related transmission has occurred remains highly debated(Han & Liu, 2022;Lewis,2021;Ma et al., 2021;Mallapaty et al., 2021;Pang et al.,2020;Wu et al., 2021). Here, we present a novel method and identify two transmission routes based on lineage-specific reductions in the SARS-CoV-2 evolutionary rate.
基金This work was financially supported by the National Natural Science Foundation of China (No.50235020).
文摘The composite films consisting of the titania gel impregnated with hydroxyapatite (HAP) submicron particles were prepared on commercial Ti6A14V plates processed by a sol-gel route. HAP powders were synthesized based on wet chemical precipitation method with Ca(NO3)2.4H2O and (NH4)2HPO4 as starting reagents. After being calcined at 900℃, HAP powders were ultrasonically scattered in ethanol to produce HAP sol. The titania sol was prepared using titanium (IV) isopropoxide {Ti[OCH(CH3)2]4} as precursor. Both the titania sol and the HAP/titania mixture were sequentially spin-coated on the substrates and calcined at various temperatures. The characteristics and mechanical adhesion of the composite films were investigated. The results show that the as-prepared films are dense, homogeneous, well-crystallized, and there is a good interfacial adhesion between the film and the substrate. The in vitro bioactivities of these films were discussed based on the analysis of the variations of Ca and P concentrations in the simulated body fluid and their surface morphologies against immersion time.