Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW l...Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, Ta, Au, Pb, Th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. The layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum,ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. Two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process.展开更多
This research study represents an ongoing research effort on Unidentified Anomalous Phenomena (UAP) with a focus on anomalous propagation of radar echo returns, mirroring established theoretical constructs of gravitat...This research study represents an ongoing research effort on Unidentified Anomalous Phenomena (UAP) with a focus on anomalous propagation of radar echo returns, mirroring established theoretical constructs of gravitational effects on light, which occur at higher frequencies and shorter wavelengths within the Electromagnetic Spectrum. These influences are also illustrated through other technologies, including Light Detection and Ranging (LIDAR) and the chromatic effects captured by hyperspectral cameras. This research addresses the complexities of interpreting unusual propagation patterns, such as Long Delay Echoes (LDE) and unexpected Field Echoes (UFE), which disrupt the anticipated propagation and echo protocols, thereby challenging our understanding and comprehension of radio transmission norms that may be influenced by a form of quantum entanglement. The paper posits a significant and largely unexamined correlation between these phenomena in the context of UAP activity, highlighting the urgent need for further research and innovative strategies in navigation technology and environmental monitoring to investigate these potential occurrences, which have remained enigmatic for nearly a century. Radar signals are vulnerable to intricate dynamics that can lead to Unusual Field Echoes (UFE), resulting in emergent anomalies, such as Multiple echo returns and LDEs. This study employed a 3-centimeter marine-based X-band radar operating in two scan geometries and a portable short-range millimeter-wave Doppler radar system. An analysis of these radar echoes over a two-year study identified signal propagation that deviated from navigational standards on Plan Position Indicators (PPI). This paper explores and investigates the potential impacts of UAP on radar transmission routes. Examining these complexities makes a case for an enhanced understanding of the interactions between established technological factors and elusive aerial phenomena.展开更多
This thesis sets out to classify the fossilized errors made by the subjects from lexical and syntactic levels respectively,through the empirical experiment and questionnaire.
Fuel cells and flow batteries are promising technologies to address climate change and air pollution problems. An understanding of the complex multiscale and multiphysics transport phenomena occurring in these electro...Fuel cells and flow batteries are promising technologies to address climate change and air pollution problems. An understanding of the complex multiscale and multiphysics transport phenomena occurring in these electrochemical systems requires powerful numerical tools. Over the past decades, the lattice Boltzmann (LB) method has attracted broad interest in the computational fluid dynamics and the numerical heat transfer communities, primarily due to its kinetic nature making it appropriate for modeling complex multiphase transport phenomena. More importantly, the LB method fits well with parallel computing due to its locality feature, which is required for large-scale engineering applications. In this article, we review the LB method for gas-liquid two-phase flows, coupled fluid flow and mass transport in porous media, and particulate flows. Examples of applications are provided in fuel cells and flow batteries. Further developments of the LB method are also outlined.展开更多
AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patie...AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs.展开更多
In this article, we consider the blowup criterion for the local strong solution to the compressible fluid-particle interaction model in dimension three with vacuum. We establish a BKM type criterion for possible break...In this article, we consider the blowup criterion for the local strong solution to the compressible fluid-particle interaction model in dimension three with vacuum. We establish a BKM type criterion for possible breakdown of such solutions at critical time in terms of both the L^∞ (0, T; L^6)-norm of the density of particles and the ^L1(0, T; L^∞)-norm of the deformation tensor of velocity gradient.展开更多
A water model with a geometric similarity ratio of 1:5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a...A water model with a geometric similarity ratio of 1:5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a NaOH solution bath. The flow field, volumetric mass transfer coefficient per unit volume (Ak/V; where A is the contact area between phases, V is the volume, and k is the mass transfer coeffi- cient), and gas utilization ratio (t/) were then measured at different gas flow rates and blow angles. The results showed that the flow field could be divided into five regions, i.e., injection, strong loop, weak loop, splashing, and dead zone. Whereas the Ak/V of the bath increased and then decreased with increasing gas flow rate, and n steadily increased. When the converter was rotated clockwise, both Ak/F and t/increased. However, the flow condition deteriorated when the gas flow rate and blow angle were drastically increased. Therefore, these para- meters must be controlled to optimal conditions. In the proposed model, the optimal gas flow rate and blow angle were 7.5 m3.h-1 and 10°, respectively.展开更多
In this paper we consider the Elastic membrane equation:with memory term and nonlinear boundary damping: Under some appropriate assumptions on the relaxation function h and with certain initial data, the global exis...In this paper we consider the Elastic membrane equation:with memory term and nonlinear boundary damping: Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions :and a general decay for the energy are established using the multiplier technique. Also, 'we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.展开更多
In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equat...In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation.展开更多
To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liq...To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liquid steel in tundish were studied. The results show that the configuration and operation of tundish play an important part in quality assurance of grade 20 carbon-steel products. By optimizing the configuration of the tundish, the depth of liquid bath in tundish is enhanced, the impact of liquid steel is decreased, and the residence time of liquid steel is lengthened, which is useful for eliminating inclusions and blowholes and improving the service life of tundish. Improving the pouring and tapping operation of liquid steel can avoid the contact of liquid steel with air, and decrease re-oxidation. Strict control of the superheat degree of casting liquid steel can decrease the non-metallic inclusion content of the re-oxidation in billets and reduce the erosion of tundish. The inclusions and blowholes in the continuous casting grade 20 steel billets are reduced to a great extent and qualification rate is enhanced from 60% to 80%.展开更多
Ionograms, which were obtained from February 1995 to January 1999 by a Digisonde Portable Sounder-4 (DPS-4) at Zhongshan Station in Antarctica, have been scaled. The ionograms interpretation has shown various ionosphc...Ionograms, which were obtained from February 1995 to January 1999 by a Digisonde Portable Sounder-4 (DPS-4) at Zhongshan Station in Antarctica, have been scaled. The ionograms interpretation has shown various ionosphcric phcnomena occurred in the cusp region. They are particle precipitation effects in the E region. F region magnetic noon phenomena, slant Es phenomena and lacuna. F layer irregularity zone (FLIZ) phenomena, and auroral oval identification. Typical examples of ionograms and ionogram sequences observed at Zhongshan Station are displayed in this paper.展开更多
基金support from the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB34030000)the National Key R & D Program of China (No.2022YFA1602404)+2 种基金National Natural Science Foundation of China (No. U1832129)the Youth Innovation Promotion Association of the Chinese Academy of Sciences (No.2017309)the Program for Innovative Research Team (in Science and Technology) in University of Henan Province of China (No.21IRTSTHN011)。
文摘Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(Smilei) is employed to simulate the entire process of Station of Extreme Light(SEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, Ta, Au, Pb, Th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. The layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum,ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. Two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process.
文摘This research study represents an ongoing research effort on Unidentified Anomalous Phenomena (UAP) with a focus on anomalous propagation of radar echo returns, mirroring established theoretical constructs of gravitational effects on light, which occur at higher frequencies and shorter wavelengths within the Electromagnetic Spectrum. These influences are also illustrated through other technologies, including Light Detection and Ranging (LIDAR) and the chromatic effects captured by hyperspectral cameras. This research addresses the complexities of interpreting unusual propagation patterns, such as Long Delay Echoes (LDE) and unexpected Field Echoes (UFE), which disrupt the anticipated propagation and echo protocols, thereby challenging our understanding and comprehension of radio transmission norms that may be influenced by a form of quantum entanglement. The paper posits a significant and largely unexamined correlation between these phenomena in the context of UAP activity, highlighting the urgent need for further research and innovative strategies in navigation technology and environmental monitoring to investigate these potential occurrences, which have remained enigmatic for nearly a century. Radar signals are vulnerable to intricate dynamics that can lead to Unusual Field Echoes (UFE), resulting in emergent anomalies, such as Multiple echo returns and LDEs. This study employed a 3-centimeter marine-based X-band radar operating in two scan geometries and a portable short-range millimeter-wave Doppler radar system. An analysis of these radar echoes over a two-year study identified signal propagation that deviated from navigational standards on Plan Position Indicators (PPI). This paper explores and investigates the potential impacts of UAP on radar transmission routes. Examining these complexities makes a case for an enhanced understanding of the interactions between established technological factors and elusive aerial phenomena.
文摘This thesis sets out to classify the fossilized errors made by the subjects from lexical and syntactic levels respectively,through the empirical experiment and questionnaire.
基金supported by the Research Grants Council of the Hong Kong Special Administrative Region, China (Grant 623313)
文摘Fuel cells and flow batteries are promising technologies to address climate change and air pollution problems. An understanding of the complex multiscale and multiphysics transport phenomena occurring in these electrochemical systems requires powerful numerical tools. Over the past decades, the lattice Boltzmann (LB) method has attracted broad interest in the computational fluid dynamics and the numerical heat transfer communities, primarily due to its kinetic nature making it appropriate for modeling complex multiphase transport phenomena. More importantly, the LB method fits well with parallel computing due to its locality feature, which is required for large-scale engineering applications. In this article, we review the LB method for gas-liquid two-phase flows, coupled fluid flow and mass transport in porous media, and particulate flows. Examples of applications are provided in fuel cells and flow batteries. Further developments of the LB method are also outlined.
文摘AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs.
基金supported by the National Basic Research Program of China(973 Program)(2011CB808002)the National Natural Science Foundation of China(11371152,11128102,11071086,and 11571117)+3 种基金the Natural Science Foundation of Guangdong Province(S2012010010408)the Foundation for Distinguished Young Talents in Higher Education of Guangdong(2015KQNCX095)the Major Foundation of Hanshan Normal University(LZ201403)the Scientific Research Foundation of Graduate School of South China Normal University(2014ssxm04)
文摘In this article, we consider the blowup criterion for the local strong solution to the compressible fluid-particle interaction model in dimension three with vacuum. We establish a BKM type criterion for possible breakdown of such solutions at critical time in terms of both the L^∞ (0, T; L^6)-norm of the density of particles and the ^L1(0, T; L^∞)-norm of the deformation tensor of velocity gradient.
基金financially supported by the National Natural Science Foundation of China(No.51504018)the China Postdoctoral Science Foundation(2015M580986)the Fundamental Research Funds for the Central Universities(FRF-TP-17-038A2)
文摘A water model with a geometric similarity ratio of 1:5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a NaOH solution bath. The flow field, volumetric mass transfer coefficient per unit volume (Ak/V; where A is the contact area between phases, V is the volume, and k is the mass transfer coeffi- cient), and gas utilization ratio (t/) were then measured at different gas flow rates and blow angles. The results showed that the flow field could be divided into five regions, i.e., injection, strong loop, weak loop, splashing, and dead zone. Whereas the Ak/V of the bath increased and then decreased with increasing gas flow rate, and n steadily increased. When the converter was rotated clockwise, both Ak/F and t/increased. However, the flow condition deteriorated when the gas flow rate and blow angle were drastically increased. Therefore, these para- meters must be controlled to optimal conditions. In the proposed model, the optimal gas flow rate and blow angle were 7.5 m3.h-1 and 10°, respectively.
文摘In this paper we consider the Elastic membrane equation:with memory term and nonlinear boundary damping: Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions :and a general decay for the energy are established using the multiplier technique. Also, 'we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.
基金supported by NSF of China (11071266)partially supported by Scholarship Award for Excellent Doctoral Student granted by Ministry of Educationpartially supported by the found of Chongqing Normal University (13XLB006)
文摘In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation.
文摘To enhance the quality of grade 20 carbon-steel on the continuous casting production line, the mechanism of forming blowholes and non-metallic inclusions in billets and numerical simulation of flow phenomena about liquid steel in tundish were studied. The results show that the configuration and operation of tundish play an important part in quality assurance of grade 20 carbon-steel products. By optimizing the configuration of the tundish, the depth of liquid bath in tundish is enhanced, the impact of liquid steel is decreased, and the residence time of liquid steel is lengthened, which is useful for eliminating inclusions and blowholes and improving the service life of tundish. Improving the pouring and tapping operation of liquid steel can avoid the contact of liquid steel with air, and decrease re-oxidation. Strict control of the superheat degree of casting liquid steel can decrease the non-metallic inclusion content of the re-oxidation in billets and reduce the erosion of tundish. The inclusions and blowholes in the continuous casting grade 20 steel billets are reduced to a great extent and qualification rate is enhanced from 60% to 80%.
文摘Ionograms, which were obtained from February 1995 to January 1999 by a Digisonde Portable Sounder-4 (DPS-4) at Zhongshan Station in Antarctica, have been scaled. The ionograms interpretation has shown various ionosphcric phcnomena occurred in the cusp region. They are particle precipitation effects in the E region. F region magnetic noon phenomena, slant Es phenomena and lacuna. F layer irregularity zone (FLIZ) phenomena, and auroral oval identification. Typical examples of ionograms and ionogram sequences observed at Zhongshan Station are displayed in this paper.