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Hydromassage of macular hole edges for large and persistent full-thickness macular holes
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作者 Yi Cai Wen-Bo Liu +5 位作者 Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期551-557,共7页
●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consec... ●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery. 展开更多
关键词 macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage
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Statistical study of magnetic holes in the upstream region of Mercury’s bow shock
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作者 GuoQiang Wang SuDong Xiao +2 位作者 MingYu Wu YuanQiang Chen TieLong Zhang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期326-337,共12页
Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the prope... Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the properties of the magnetic holes with shorter durations are still unclear.Here,we investigate the magnetic holes with durations of 0.1-100 s in the upstream region of Mercury’s bow shock based on observations by the MESSENGER(MErcury Surface,Space ENvironment,GEochemistry,and Ranging)spacecraft.They can be divided into two groups according to the distribution of their duration:small-duration magnetic holes(SDMHs,<0.6 s)and large-duration magnetic holes(LDMHs,>0.6 s).The duration of each group approximately obeys a log-normal distribution with a median of~0.25 s and 3 s,respectively.Approximately 1.7%(32.6%)of the SDMHs(LDMHs)reduce the magnetic field strength by more than 50%.For both groups,some structures have a linear or quasi-linear polarization,whereas others have an elliptical polarization.The magnetic hole events in both groups tend to have a higher rate of occurrence when the interplanetary magnetic field strength is weaker.Their occurrence rates are also affected by Mercury’s foreshock,which can increase(decrease)the occurrence rate of the SDMHs(LDMHs).This finding suggests that Mercury’s foreshock might be one source of the SDMHs and that the foreshock can destroy some LDMHs.These observations suggest that a new group of magnetic holes with durations of<0.6 s exist in the upstream region of Mercury’s bow shock. 展开更多
关键词 magnetic hole solar wind MERCURY FORESHOCK
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View of thermodynamic phase transition of the charged Gauss-Bonnet AdS black hole via the shadow
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作者 何柯腱 郭森 +1 位作者 罗智 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期355-362,共8页
We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),a... We examine thermodynamic phase transition(PT)of the charged Gauss-Bonnet Ad S black hole(BH)by utilizing the shadow radius.In this system,we rescale the corresponding Gauss-Bonnet coefficientαby a factor of 1/(D-4),and ensure thatαis positive to avoid any singularity problems.The equation derived for the shadow radius indicates that it increases as the event horizon radius increases,making it an independent variable for determining BH temperature.By investigating the PT curve in relation to shadows,we can observe that the shadow radius can be used as an alternative to the event horizon radius in explaining the phenomenon of BH PT.Furthermore,the results indicate that an increase in the parameterαcorresponds to a decrease in the temperature of the BH.By utilizing the relationship between the temperature and the shadow radius,it is possible to obtain the thermal profile of the Gauss-Bonnet AdS BH.It is evident that there is an N-type variation in temperature for pressures P<P_(c).Additionally,as the parameterαincreases,the region covered by shadow expands while the temperature decreases.The utilization of BH shadows as a probe holds immense significance in gaining a deeper understanding of BH thermodynamic behavior. 展开更多
关键词 Gauss-Bonnet AdS black hole thermodynamic SHADOW
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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity
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作者 牟平辉 蒋青权 +1 位作者 何柯腱 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期272-287,共16页
By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnet... By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other dimensions.Specifically, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity. 展开更多
关键词 AdS black hole phase transition triple point
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Enhanced magnetic anisotropy and high hole mobility in magnetic semiconductor Ga_(1-x-y)Fe_(x)Ni_(y)Sb
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作者 Zhi Deng Hailong Wang +5 位作者 Qiqi Wei Lei Liu Hongli Sun Dong Pan Dahai Wei Jianhua Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期16-21,共6页
(Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,F... (Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,Fe)Sb is below 7.6×10^(3)erg/cm^(3)when Fe concentration is lower than 30%,which is one order of magnitude lower than that of(Ga,Mn)As.To address this issue,we grew Ga_(1-x-y)Fe_(x)Ni_(y)Sb films with almost the same x(≈24%)and different y to characterize their magnetic and electrical transport properties.We found that the magnetic anisotropy of Ga_(0.76-y)Fe_(0.24)Ni_(y)Sb can be enhanced by increasing y,in which Ku is negligible at y=1.7%but increases to 3.8×10^(5)erg/cm^(3)at y=6.1%(T_(C)=354 K).In addition,the hole mobility(μ)of Ga_(1-x-y)Fe_(x)Ni_(y)Sb reaches 31.3 cm^(2)/(V∙s)at x=23.7%,y=1.7%(T_(C)=319 K),which is much higher than the mobility of Ga_(1-x)Fe_(x)Sb at x=25.2%(μ=6.2 cm^(2)/(V∙s)).Our results provide useful information for enhancing the magnetic anisotropy and hole mobility of(Ga,Fe)Sb by using Ni co-doping. 展开更多
关键词 magnetic semiconductor molecular beam epitaxy Fe-Ni co-doping magnetic anisotropy hole mobility
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Thermodynamics in a quantum corrected Reissner-Nordstr?m-AdS black hole and its GUP-corrections
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作者 宋建君 刘成周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期345-353,共9页
We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and ... We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and the remnant state,respectively,and discuss their consistency.Then,we investigate the quantum tunneling from the event horizon of massless scalar particle by using the null geodesic method,and charged massive boson W^(±)and fermions by using the Hamilton-Jacob method.It is shown that the same Hawking temperature can be obtained from these tunneling processes of different particles and methods.Next,by using the generalized uncertainty principle(GUP),we study the quantum corrections to the tunneling and the temperature.Then the logarithmic correction to the black hole entropy is obtained. 展开更多
关键词 black hole thermodynamics quantum corrections quantum tunneling generalized uncertainty principle
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Generalized Newton’s Theory of Universal Gravitation and Black Holes
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作者 Lenser Aghalovyan 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期126-137,共12页
The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with... The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*. 展开更多
关键词 GRAVITATION Central Interaction Escape Velocity Black hole Horizon of Events
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Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes
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作者 Jingtong Bin Kerui Feng +4 位作者 Shang Ma Ke Liu Yong Cheng Jing Chen Qifa Liu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期63-70,共8页
A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefin... A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefinite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be confined within a small mode volume to achieve an ultra-high Q/Vm ratio. 展开更多
关键词 Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation Quality factor Mode volume
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Quantum Unruh Effect on Radiation of Black Holes
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作者 Tianxi Zhang 《Journal of Modern Physics》 2024年第6期938-949,共12页
The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applyi... The quantum Unruh effect on radiation of a gravitational object including a black hole is analyzed and calculated. It is surprisingly found that the well-known Hawking radiation of a black hole is not physical. Applying the Stephan-Boltzmann law with the use of the Unruh radiation temperature at the surface of a black hole to calculate the power of radiation of the black hole is conceptually unphysical. This is because the Unruh radiation temperature results from the gravitational field of the object rather than from the thermal motion of matter of the object, so that the Stephan-Boltzmann law is not applicable. This paper shows that the emission power of Unruh radiation from a gravitational object should be calculated in terms of the rate of increase of the total Unruh radiation energy outside the object. The result obtained from this study indicates that a gravitational object can emit Unruh radiation when the variation of its mass and radius satisfies an inequality of dM/M > 1.25dR/R. For a black hole, the emission of Unruh radiation does not occur unless it can loose its mass (dM < 0). The emission power of Unruh radiation is only an extremely tiny part of the rate of mass-energy loss if the black hole is not extremely micro-sized. This study turns down our traditional understanding of the Hawking radiation and thermodynamics of black holes. 展开更多
关键词 Black hole GRAVITATION Quantum Field Theory Blackbody Radiation
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Black Hole Singularities and Planetary Formation
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作者 Louise Riofrio 《Journal of Applied Mathematics and Physics》 2024年第4期1079-1088,共10页
The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift o... The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift observations from the James Webb Space Telescope reveal that distant galaxies and their central black holes formed shortly after the Big Bang. An innovation about the speed of light explains how supermassive black holes could have formed primordially. Predictions of Hawking radiation include the possibility of black holes contributing to the energy of stars such as the Sun. Black holes have also been suggested as a source of radiation and magnetic fields in giant planets. Observations of Enceladus raise the possibility that this moon and other objects near Saturn’s Rings contain small singularities. Extrapolations of this methodology indicate that black holes could exist within solar system bodies including planets. Extended discussion describes how their presence could explain mysteries of internal heat, planetary magnetic fields, and processes of solar system formation. 展开更多
关键词 Black holes GALAXIES Magnetic Fields Planets Planetary Formation Speed of Light
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On Our Peculiar Black Hole Universe
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作者 Paolo Christillin 《Journal of Modern Physics》 2024年第2期179-183,共5页
The black hole model of the Universe evolution, accompanied by matter creation, already successfully accounting for many features of the past is discussed and further justified. It is once more stressed that even a ve... The black hole model of the Universe evolution, accompanied by matter creation, already successfully accounting for many features of the past is discussed and further justified. It is once more stressed that even a very large object but with a big mass is in its own right a black hole. As a consequence, the extrapolation of the past predicts for the future no big crunch, nor big bounce but a steady expansion with smaller matter density. 展开更多
关键词 Universe Expansion Black hole Model Matter Creation Gravitational Self Energy
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Black Hole Complementarity in Terms of the Outsider and Insider Perspectives
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期184-192,共9页
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation... A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling. 展开更多
关键词 Black holes Complementarity Cosmological Models Rh = ct Models Flat Space Cosmology Schwarzschild Cosmology Thought Experiment Dark Energy Quantum Vacuum
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O型臂导航辅助经皮内镜下Key-hole术式治疗神经根型颈椎病的临床疗效 被引量:1
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作者 潘才成 覃梁圣 +3 位作者 黄珩 贺庆 肖侃侃 卓祥龙 《中国脊柱脊髓杂志》 CAS CSCD 北大核心 2023年第6期523-529,共7页
目的:评价O型臂导航辅助经皮内镜下Key-hole术式治疗单节段神经根型颈椎病(cervical spondylotic radiculopathy,CSR)的临床疗效。方法:回顾性分析2018年9月~2020年6月在我院接受O型臂导航辅助经皮内镜下Key-hole术式治疗的单节段CSR患... 目的:评价O型臂导航辅助经皮内镜下Key-hole术式治疗单节段神经根型颈椎病(cervical spondylotic radiculopathy,CSR)的临床疗效。方法:回顾性分析2018年9月~2020年6月在我院接受O型臂导航辅助经皮内镜下Key-hole术式治疗的单节段CSR患者22例,其中男14例,女8例,年龄54.05±10.67岁(32~71岁);C5/6节段8例,C6/7节段13例,C7/T1节段1例。记录手术时间、术中出血量、术后住院时间及并发症情况;术前、术后3d及末次随访时采用视觉模拟评分量表(visual analogue scale,VAS)、颈部功能障碍指数(neck disability index,NDI)进行疼痛和功能评定,末次随访时根据改良Macnab标准评定疗效;术前、术后3d及末次随访时进行X线片、CT及MRI检查,测量手术节段椎间隙高度(disc height,DH)、下颈椎曲度(cervical spinal angle,CSA)及侧块关节平面切除率(facet resection rate,FRR)。结果:所有患者手术均顺利完成,随访时间36.85±5.83个月(25~44个月)。手术时间为120.32±33.92mins(76~209mins),术中出血量为14.86±12.67ml(2~50ml),术后住院时间为4.05±1.70d(2~9d)。手术并发症3例,其中1例术中C7神经根损伤致右肱三头肌肌力明显下降至2级,末次随访时肌力恢复至5级;1例术中发生椎动脉钳夹损伤出血,即刻使用凝胶海绵填塞止血,术后影像学显示无血肿形成,未诉特殊不适;1例术后出现轻度神经放射痛,经药物治疗后改善。与术前相比,术后3d、末次随访时颈痛VAS评分及NDI均得到显著改善(P<0.05);末次随访时改良MacNab标准评分优17例、良4例、可1例,优良率为95.5%。术前、术后3d及末次随访时DH分别为4.40±0.97mm、4.31±0.92mm及4.26±1.01mm,CSA分别为5.70°±16.94°、8.43°±15.59°及11.44°±13.80°,术前、术后3d及末次随访时DH及CSA相比较,差异均无统计学意义(P>0.05)。FRR为(27.12±16.62)%。结论:O型臂导航辅助经皮内镜下Key-hole术式治疗CSR安全有效,具有工作套管精准置入,降低手术损伤的优点。 展开更多
关键词 神经根型颈椎病 O型臂导航 脊柱内镜 Key-hole术式
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Gelation of Hole Transport Layer to Improve the Stability of Perovskite Solar Cells 被引量:1
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作者 Ying Zhang Chenxiao Zhou +7 位作者 Lizhi Lin Fengtao Pei Mengqi Xiao Xiaoyan Yang Guizhou Yuan Cheng Zhu Yu Chen Qi Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期305-316,共12页
To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adeq... To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adequate passivation capability is important. To achieve enough conductivity and effective hole extraction, spiro-OMe TAD, one of the most frequently used HTL in optoelectronic devices, often needs chemical doping with a lithium compound(LiTFSI). However, the lithium salt dopant induces crystallization and has a negative impact on the performance and lifetime of the device due to its hygroscopic nature. Here, we provide an easy method for creating a gel by mixing a natural small molecule additive(thioctic acid, TA) with spiro-OMe TAD. We discover that gelation effectively improves the compactness of resultant HTL and prevents moisture and oxygen infiltration. Moreover, the gelation of HTL improves not only the conductivity of spiro-OMe TAD, but also the operational robustness of the devices in the atmospheric environment. In addition, TA passivates the perovskite defects and facilitates the charge transfer from the perovskite layer to HTL. As a consequence, the optimized PSCs based on the gelated HTL exhibit an improved PCE(22.52%) with excellent device stability. 展开更多
关键词 Perovskite solar cell hole transport layer GELATION Humidity stability Aggregation of LiTFSI
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Stress release mechanism of deep bottom hole rock by ultra-high-pressure water jet slotting 被引量:1
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作者 Hua-jian Wang Hua-Lin Liao +6 位作者 Jun Wei Jian-Sheng Liu Wen-Long Niu Yong-Wang Liu Zhi-Chuan Guan Hedi Sllami John-Paul Latham 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1828-1842,共15页
To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is proposed.The stress conditions of bottom... To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is proposed.The stress conditions of bottom hole rock,before and after slotting are analyzed and the stress release mechanism of slotting is clarified.The results show that the stress release by slotting is due to the coupling of three factors:the relief of horizontal stress,the stress concentration zone distancing away from the cutting face,and the increase of pore pressure caused by rock mass expansion;The stress concentration increases the effective stress of rock along the radial distance from O.6R to 1R(R is the radius of the well),and the presence of groove completely releases the stress,it also allows the stress concentration zone to be pushed away from the cutting face,while significantly lowering the value of stresses in the area the drilling bit acting,the maximum stress release efficiency can reach 80%.The effect of slotting characteristics on release efficiency is obvious when the groove location is near the borehole wall.With the increase of groove depth,the stress release efficiency is significantly increased,and the release range of effective stress is enlarged along the axial direction.Therefore,the stress release method and results of simulations in this paper have a guiding significance for best-improving rock-breaking efficiency and further understanding the technique. 展开更多
关键词 Hard rock SLOTTING Stress release Down hole pressures Poroelastic mechanics Fluid-structure Interaction Ultra-high-pressure water jet
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Hole fertilization in the root zone facilitates maize yield and nitrogen utilization by mitigating potential N loss and improving mineral N accumulation 被引量:1
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作者 SHI Wen-xuan ZHANG Qian +3 位作者 LI Lan-tao TAN Jin-fang XIE Ruo-han WANG Yi-lun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1184-1198,共15页
Reducing environmental impacts and improving N utilization are critical to ensuring food security in China.Although root-zone fertilization has been considered an effective strategy to improve nitrogen use efficiency ... Reducing environmental impacts and improving N utilization are critical to ensuring food security in China.Although root-zone fertilization has been considered an effective strategy to improve nitrogen use efficiency (NUE),the effect of controlled-release urea (CRU) applied in conjunction with normal urea in this mode is unclear.Therefore,a 3-year field experiment was conducted using a no-N-added as a control and two fertilization modes (FF,furrow fertilization by manual trenching,i.e.,farmer fertilizer practice;HF:root-zone hole fertilization by point broadcast manually) at 210 kg N ha^(–1) (controlled-release:normal fertilizer=5:5),along with a 1-year in-situ microplot experiment.Maize yield,NUE and N loss were investigated under different fertilization modes.The results showed that compared with FF,HF improved the average yield and N recovery efficiency by 8.5 and 22.3%over three years,respectively.HF had a greater potential for application than FF treatment,which led to increases in dry matter accumulation,total N uptake,SPAD value and LAI.In addition,HF remarkably enhanced the accumulation of ^(15)N derived from fertilizer by 17.2%compared with FF,which in turn reduced the potential loss of^(15)N by 43.8%.HF increased the accumulation of N in the tillage layer of soils at harvest for potential use in the subsequent season relative to FF.Hence,HF could match the N requirement of summer maize,sustain yield,improve NUE and reduce environmental N loss simultaneously.Overall,root-zone hole fertilization with blended CRU and normal urea can represent an effective and promising practice to achieve environmental integrity and food security on the North China Plain,which deserves further application and investigation. 展开更多
关键词 maize yield hole fertilization NUE ^(15)N-labeled blended urea ^(15)N loss
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A Number Estimate of Detectable Detached Black Hole-star Binaries using a Photometric Telescope
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作者 Zhe-Cheng Hu Yan-Lv Yang +2 位作者 Yuan-Hao Wen Rong-Feng Shen Pak-Hin Thomas Tam 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期141-152,共12页
Detached and wide-orbit black hole-star binaries(BHSBs)can generate three types of periodic photometric signals:Ellipsoidal Variation,Doppler beaming and Self-Lensing(SL),providing a proxy to discover these black hole... Detached and wide-orbit black hole-star binaries(BHSBs)can generate three types of periodic photometric signals:Ellipsoidal Variation,Doppler beaming and Self-Lensing(SL),providing a proxy to discover these black holes.We estimate the relative amplitude of the three signals for such systems and the detectability for black holes of a photometric telescope like Kepler in several steps.We estimate the searchable star number by assuming every star has a black hole companion,and apply the occurrence of BHSBs in field stars to estimate the detectable black hole signals.We consider three types of Initial Mass Function(IMF)model with different high end exponential slopes.“When spot and white noise are both considered,there is about one detectable signal for SL and less than one event is expected for beaming and Ellipsoidal Variation signal in Kepler Input Catalog stars with the standard IMF model.”to“Due to contamination by stellar spots and white noise,one may expect one detectable signal for SL and less than one detectable signal for both beaming and Ellipsoidal Variation in Kepler Input Catalog stars with the standard IMF model.”On the other hand,if we assume that only white noise affects the detection efficiency of the BHSBs,we expect about 10 Ellipsoidal Variation signals and 17 beaming signals to be detectable while the number of SL signals remains unchanged. 展开更多
关键词 black hole physics-techniques photometric-surveys-stars black holes-stars variables general
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Hawking Temperature and the Quantum Pressure of the Schwarzschild Black Hole
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作者 Kapil P. Chandra 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期515-518,共4页
There is no term for pressure ( P∇V) in the first law of black hole thermodynamics. To address this question, we study the first law of black hole thermodynamics and derive an expression for it. We report that this pr... There is no term for pressure ( P∇V) in the first law of black hole thermodynamics. To address this question, we study the first law of black hole thermodynamics and derive an expression for it. We report that this pressure corresponds to the Hawking temperature and is inversely proportional to the quartic of the Schwarzschild radius. It implies that a lighter and smaller black hole exerts more pressure on its surrounding environment. It might shed light on the other thermodynamic aspects of the black hole. 展开更多
关键词 Hawking Temperature Black hole Thermodynamics Black holes
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The shadow and observation appearance of black hole surrounded by the dust field in Rastall theory
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作者 朱轩然 陈芸仙 +1 位作者 牟平辉 何柯腱 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期196-206,共11页
In the context of Rastall gravity,the shadow and observation intensity casted by the new Kiselev-like black hole with dust field have been numerically investigated.In this system,the Rastall parameter and surrounding ... In the context of Rastall gravity,the shadow and observation intensity casted by the new Kiselev-like black hole with dust field have been numerically investigated.In this system,the Rastall parameter and surrounding dust field structure parameter have considerable consequences on the geometric structure of spacetime.Considering the photon trajectories near the black hole,we investigate the variation of the radii of photon sphere,event horizon and black hole shadow under the different related parameters.Furthermore,taking into account two different spherically symmetric accretion models as the only background light source,we also studied the observed luminosity and intensity of black holes.For the both spherical accretions background,the results show that the decrease or increase of the observed luminosity depends on the value range of relevant parameters,and the promotion effect is far less obvious than the attenuation effect on the observed intensity.One can find that the inner shadow region and outer bright region of the black hole wrapped by infalling accretion are significantly darker than those of the static model,which is closely related to the Doppler effect.In addition,the size of the shadow and the position of the photon sphere are always the same in the two accretion models,which means that the black hole shadow depend only on the geometry of spacetime,while the observation luminosity is affected by the form of accretion material and the related spacetime structure. 展开更多
关键词 Rastall gravity black hole
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Construction and Weight Distributions of Binary Linear Codes Based on Deep Holes
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作者 Yong Yang Wenwei Qiu 《Applied Mathematics》 2023年第10期684-695,共12页
Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, ... Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, we consider constructing binary linear codes by combining deep holes with binary BCH codes. In this article, we consider the 2-error-correcting binary primitive BCH codes and the extended codes to construct new binary linear codes by combining them with deep holes, respectively. Furthermore, three classes of binary linear codes are constructed, and then we determine the parameters and the weight distributions of these new binary linear codes. 展开更多
关键词 Linear Codes MacWilliams Equations Weight Distribution Dual Codes Deep holes Covering Radius
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