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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 61-70页

作者： Xu-Chang zheng Chao-Hsi Chang tai-Fu Feng Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China China Center of Advanced Science and Technology(CCAST)(World Laboratory) Beijing 100190China Department of Physics Hebei UniversityBaoding 071002China

To test the standard model(SM)precisely and to look for the clues deviating from SM,a proposal for determining the effective electro-weak mixing angles sin2θefff(particularly f=lept,c,b)is *** is via observing the asymmetries(the forward-backward one AFB,the left-right one ALR and the combined left-right forward-backward one ALRFB)of the doubly heavy-flavored hadrons in the production at a super Z-factory(an e+e-collider designed with a luminosity as high as possible for modernday techniques runs around the center-of-mass energy s1/2=mZ).To see the sensitivity,uncertainties as well as the event accumulation precisely,the observables for describing the asymmetries of the produced hadrons are computed numerically with varying effective mixing angles,and based on the result analyses,it is concluded that the proposal may offer an independent complement determination of the effective mixing angles.

关键词： electro-weak mixing angle production of doubly heavy-flavored hadron asymmetries super Z-factory

Biomechanics of sclera crosslinked using genipin in rabbit

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International Journal of Ophthalmology(English edition) 2017年第3期10卷 355-360页

作者： tai-Xiang Liu zheng Wang Guizhou Ophthalmic Hospital Affiliated Hospital of Zunyi Medical College Ztmyi 563003 Guizhou Province China Zhongshan Ophthalmic Center of sun Yat-sen University the State Key Laboratory of Ophthalmology Guangzhou 510060 Guangdong Province China

AIM：To strengthen the biomechanics of collagen by crosslinking rabbit scleral collagen with genipin to develop a new therapy for preventing myopic progression. METHODS：Ten New Zealand rabbits were treated with 0.5 mmol/L genipin injected into the sub-Tenon＇s capsule in the right eyes. Untreated contralateral eyes served as the control. The treated area was cut into scleral strips measuring 4.0 mm×10.0 mm for stress-strain measurements（n=5）. The remaining five treated eyes were prepared for histological ***：Compared to the untreated scleral strips,the genipin-crosslinked scleral strips showed that the ultimate stress and Young＇s modulus at 10% strain were increased by the amplitude of 130% and 303% respectively,ultimate strain was decreased by 24%. There had no α-smooth muscle actin（α-SMA）positive cells in control and treated sclera. Histologically,there was no sign of apoptosis in the sclera,choroid,and retina; and no side effects were found in the peripheral cornea and optic nerve adjacent to the treatment ***：Genipin induced crosslinking of collagen can increase its biomechanical behavior by direct strengthening of the extracellular matrix in rabbit sclera,with no α-SMA expression seen in the myofibroblasts. As there is no evidence of cytotoxicity in the scleral,choroidal,and retinal cells,genipin is likely a promising agent to strengthen the weakened sclera to prevent myopic progression.

关键词： genipin crosslinking biomechanics sclera myopia

Breakage and shape analysis of ballast aggregates with different size distributions

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Particuology 2017年第6期15卷 84-92页

作者： Yifei sun Changjie zheng Key Laboratory ofMinistryof Education for Geomechanics and Embankment Engineering College of Civil and Transportation Engineering Hohai University Nanjing 210098 China School of Civil Mining and Environmental Engineering University ofWollongong Wollongong NSW2522 Australia Key Laboratory of New Technology for Consgruction of Cities in Mountain Area Ministry of Education School of Civil Engineering Chongqing University Chongqing 400045 China

Particle breakage usually alters the size and shape of ballast aggregates, which significantly influences the long-term performance of rail tracks. This study reports an investigation on the breakage and shape characteristics of ballast aggregates subjected to monotonic and cyclic triaxial tests with two different load frequencies. The results show that particle breakage is not only influenced by the particle size distribution but also by the relative density. Breakage indices defined by breakage potential and grading entropy fail to characterize the breakage extent of ballast with multiple initial particle size distributions, while the Marsal breakage index exhibits a general decrease with increasing coefficient of uniformity for ballast with similar relative densities. Higher breakage extent is observed in ballast subjected to a higher load frequency. Particle shape varies with load frequency because of breakage. A slightly higher value of each shape index is observed for ballast subjected to a higher load frequency, implying that ballast aggregates become increasingly regular with the increase of load frequency,

关键词： Breakage Breakage potentia Grading entropy Particle shape Ballast

The possible KK^(*)and D^(*)bound and resonance states by solving the Schrodinger equation

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Communications in Theoretical Physics 2024年第10期76卷 85-91页

作者： Bao-Xi sun Qin-Qin Cao Ying-tai sun School of Physics and Optoelectronic Engineering Beijing University of TechnologyBeijing 100124China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The Schrodinger equation with a Yukawa type of potential is solved *** different boundary conditions are taken into account,a series of solutions are indicated as a Bessel function,the first kind of Hankel function and the second kind of Hankel function,***,the scattering processes of K^(*)and D^(*)are *** the K^(*)sector,the f_(1)(1285)particle is treated as a K^(*)bound state,therefore,the coupling constant in the K^(*)Yukawa potential can be fixed according to the binding energy of the f_(1)(1285)***,a K^(*)resonance state is generated by solving the Schrodinger equation with the outgoing wave condition,which lies at 1417-i18 MeV on the complex energy *** is reasonable to assume that the K^(*)resonance state at 1417-i18 MeV might correspond to the f_(1)(1420)particle in the review of the Particle Data *** the D^(*)sector,since the X(3872)particle is almost located at the D^(*)threshold,its binding energy is approximately equal to ***,the coupling constant in the D^(*)Yukawa potential is determined,which is related to the first zero point of the zero-order Bessel *** to the K^(*)case,four resonance states are produced as solutions of the Schrodinger equation with the outgoing wave *** is assumed that the resonance states at 3885~i1 MeV,4029-i108 MeV,4328-i191 MeV and 4772-i267 MeV might be associated with the Zc(3900),the X(3940),theχ_(c1)(4274)andχ_(c1)(4685)particles,*** is noted that all solutions are isospin degenerate.

关键词： non-Hermitian quantum mechanics Schrodinger equation meson-meson interaction one-pion exchanging potential resonance state bound state

On-chip stackable dielectric laser accelerator

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Nuclear Science and Techniques 2023年第2期34卷 79-87页

作者： Bin sun Yang‑Fan He Ruo‑Yun Luo tai‑Yang Zhang Qiang Zhou Shao‑Yi Wang Jian zheng Zong‑Qing Zhao CAS Key Laboratory of Geospace Environment Department of Plasma Physics and Fusion EngineeringUniversity of Science and Technology of ChinaHefei 230026China Laser Fusion Research Center CAEPP.O.Box 919986Mianyang 621900China The Sciences and Technology on Plasma Physics Laboratory CAEPMianyang 621900China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Nuclear Plasmaand Radiological EngineeringUniversity of Illinois at Urbana-Champaign104 South Wright StreetUrbanaIL 61801USA CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

In this paper,we propose a novel stacked laser dielectric acceleration *** structure is based on the inverse Cherenkov effect and represented by a parametric design *** to existing dielectric laser accelerators relying on the inverse Smith–Purcell effect,the proposed structure provides an extended-duration synchronous acceleration field without requiring the pulse front tilting *** advantage significantly reduces the required pulse *** addition,the easy to integrate layered structure facilitates cascade acceleration,and simulations have shown that low-energy electron beams can be cascaded through high gradients over extended *** practical advantages demonstrate the potential of this new structure for future chip accelerators.

关键词： Dielectric laser accelerator Inverse Cherenkov effect Laser-driven particle acceleration

Surface Grafting of Phenolic Resole onto LDPE Films

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Chinese Chemical Letters 2006年第8期17卷 1133-1136页

作者： Jue CHENG Yi zheng Wan tai YANG Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing 100029 College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029

Low density polyethylene film surface-grafted phenolic resole was prepared by a sequential processes. Firstly, acrylic acid was grafted to the surface of low density polyethylene by photo-grafting. Secondly, the carboxylic groups in poly（acrylic acid） chains were transferred to sulfonic groups by the reaction of carboxylic groups with sulfanilic acid. Finally, a thin layer of phenolic resole was cured onto the surface of low density polyethylene. The grafting process was characterized by FTIR-ATR and gravimetric analysis. A possible model was proposed to interpret the experimental results.

关键词： Surface grafting low density polyethylene film sulfanilic acid phenolic resole.

A new measure of nystagmus acuity

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International Journal of Ophthalmology(English edition) 2014年第1期7卷 95-99页

作者： Jun-Ping Yao zheng tai zheng-Qin Yin Department of Ophthalmology Tianyou HospitalWuhan University of Science and Technology Chongqing Key Lab of Visual Damage and Regeneration & Restoration Chongqing Broadcasting Group Department of Ophthalmology Southwest HospitalThird Military Medical University

AIM: To construct a new visual acuity measuring function for congenital nystagmus(CN) patients by studying the relationships between acuity,velocities and positions of the eye. ·METHODS: After assessing the relationship between acuity,movement velocities and positions of the eye separately,a new function,which we call the automated nystagmus acuity function(ANAF),was constructed to measure the visual acuity of CN patients. Using a high-speed digital video system working at 500 frames per second,each eye was calibrated during monocular fixation. Twenty-six recorded nystagmus data were selected randomly. Using nystagmus waveforms,the best vision position(foveation period) and visual acuity were analyzed in three groups of subjects,and then all outputs were compared with the well-known expanded nystagmus acuity function(NAFX) and ANAF. Standard descriptive statistics were used to summarize the outputs of the two programs. ·RESULTS: Foveation periods were brief intervals in the CN waveform when the image was on or near the fovea and eye velocity was relatively slow. Results showed good visual acuity happened during the period when velocity was low and the eye position was near the zero position,which fitted the foveation periods. The data analyzed with NAFX and ANAF had a correlation coefficient of 0.934276,with an average error of-0.00973. · CONCLUSION: The results from ANAF and NAFX analyses showed no significant difference. The NAFX manually identifies foveation eye positions and produces accurate measurements. The ANAF,however,can be calculated simply using the factors eye position andvelocity,and it automatically calculates the ANAF without the need to manually identify foveation eye positions.

关键词： nystagmus vision acuity nystagmus acuity function eye movement measurements

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三花枪刀药化学成分研究

天然产物研究与开发 2001年第6期13卷 12-15页

作者：姜北赵勤实林中文吕扬郑启泰孙汉董中国科学院昆明植物研究所植物化学开放研究实验室昆明650204 中国医学科学院药物研究所北京100050

由爵床科枪刀药属植物三花枪刀药 (Hypoestestriflora)的地上部分丙酮提取物中分离得到了 6个化合物 ,通过波谱分析及晶体X射线衍射分析确定为 :尿囊素 (allantoin) (1) ,β 谷甾醇 (2 ) ,胡萝卜甙(3) ,硬脂酸 (4 ) ,黄木灵 (xanthoxyli... 详细信息

由爵床科枪刀药属植物三花枪刀药 (Hypoestestriflora)的地上部分丙酮提取物中分离得到了 6个化合物 ,通过波谱分析及晶体X射线衍射分析确定为 :尿囊素 (allantoin) (1) ,β 谷甾醇 (2 ) ,胡萝卜甙(3) ,硬脂酸 (4 ) ,黄木灵 (xanthoxylin) (5 )和无机盐硝酸钾 (6 ) ,这些成分均为首次由该种植物中分离得到。

关键词：三花枪刀药爵床科化学成分尿囊素

Nature of the Ga-Ga bonding in Na_2[Arx~*GaGaArx~*](Arx~*=C_6H_3 -2,6-(C_6H_5)_2):Electron localization function analysis

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Science China Chemistry 2012年第7期55卷 1370-1376页

作者： sun Jie MENG LingPeng zheng ShiJun sun zheng LI XiaoYan College of Chemistry and Material Science Hebei Normal UniversityShijiazhuang 050016China

The nature of the Ga-Ga bonding in Na2[Arx＊GaGaArx＊] （Arx＊ = C6H3-2,6-（C6Hs）2） has been investigated and compared with that of in Hz[Arx＊GaGaArx＊] using electron localization function （ELF） and orbital analysis. The calculation results show that in Na2[Arx＊GaGaArx＊], the Ga-Ga interaction is a non-classical triple bond, the heart of Na2[Arx＊GaGaArx＊] is the Ga2Na2 cluster rather than a simple Ga-Ga bond, and the contribution of the sodium atoms to the short Ga-Ga bond length is considerable. As the two sodium atoms are substituted by two hydrogen atoms, the Ga-Ga bond is replaced by two 3-center, 2-electron （3c-2e） Ga-H-Ga covalent bridged bonding.

关键词： Ga-Ga bonding electron localization function hydrogen bridged bond

An Efficient Multiple Imputation Approach for Estimating Equations with Response Missing at Random and High-Dimensional Covariates

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Journal of Systems Science & Complexity 2021年第1期34卷 440-464页

作者： WANG Lei sun Siying XIA zheng School of Statistics and Data Science LPMC&KLMDASRNankai UniversityTianjin 300071China

Empirical-likelihood-based inference for parameters defined by the general estimating equations of Qin and Lawless(1994) remains an active research topic. When the response is missing at random(MAR) and the dimension of covariate is not low, the authors propose a two-stage estimation procedure by using the dimension-reduced kernel estimators in conjunction with an unbiased estimating function based on augmented inverse probability weighting and multiple imputation(AIPW-MI) methods. The authors show that the resulting estimator achieves consistency and asymptotic normality. In addition, the corresponding empirical likelihood ratio statistics asymptotically follow central chi-square distributions when evaluated at the true parameter. The finite-sample performance of the proposed estimator is studied through simulation, and an application to HIV-CD4 data set is also presented.

关键词： Consistency and asymptotic normality dimension reduction kernel-assisted missing at random multiple imputation