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Imaging characteristics and surgical management of orbital neurilemmomas
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作者 Ming-Hao Chen Jian-Hua Yan 《国际眼科杂志:英文版》 SCIE CAS 2019年第7期1108-1115,共8页
AIM: To review imaging characteristics and surgical outcomes of orbital neurilemmoma. METHODS: Retrospective review of 21 patients with orbital neurilemmoma managed at the Zhongshan Ophthalmic Center of Sun Yat-sen Un... AIM: To review imaging characteristics and surgical outcomes of orbital neurilemmoma. METHODS: Retrospective review of 21 patients with orbital neurilemmoma managed at the Zhongshan Ophthalmic Center of Sun Yat-sen University from June 2005 to December 2016. All patients underwent surgical excision following preoperative imaging including ultrasonography, computed tomography(CT) and magnetic resonance imaging(MRI).RESULTS: Among these patients, 11 were male and 10 were female, with age ranging from 12 to 75y(average, 40.3 y). Ultrasound of the orbit showed a roundish well-demarcated orbital mass with low or middle internal reflectivity in each case. Dark inner liquid fields were detected in 28.6% of these cases. Doppler ultrasound demonstrated blood flow signals in these masses. CT showed that the tumors were either homogeneous or heterogeneous. MRI of T1 WI revealed isointense or hypointense tumors, while the T2 WI indicated heterogeneous hyperintense lesions. Gd contrast MRI demonstrated heterogenous or homogeneous enhancement initiating from the wide area of the lesion. Six patients underwent lateral orbitotomy and 15 anterior orbitotomy. All tumors were completely removed. After a mean followup of 1.8 y, 3 patients experienced reduced vision while the remaining 10 patients showed improved vision after surgery. One patient experienced a mild limitation of upward motility. No recurrence occurred. CONCLUSION: Orbital neurilemmoma is a relatively rare, benign orbital tumor. Effective diagnosis requires a combination of ultrasonography, CT and/or MRI. These imaging techniques are also vital to differentiate neurilemmomas from other orbital masses like that of cavernous hemangiomas and meningiomas.Successful treatment requires complete resection of the neurilemmomas as performed either by lateral or anterior orbitotomy. Recurrence is rare after complete removal. 展开更多
关键词 NEURILEMMOMA ORBITAL TUMOR IMAGING ORBITOTOMY ORBITAL SURGERY
A review of multiple optical vortices generation: methods and applications
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作者 Long ZHU Jian WANG 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期52-68,共17页
Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical ... Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical communications.In various optical vortices enabled applications,the generation of multiple optical vortices is of great importance.In this review article,we focus on the methods of multiple optical vortices generation and its applications.We review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM modes.Diverse applications of multiple OAM modes in optical communications and non-communication areas are presented.Future trends,perspectives and opportunities are also discussed. 展开更多
关键词 OPTICAL communications OPTICAL VORTICES ORBITAL angular momentum (OAM) mode-division MULTIPLEXING (MDM) MODE MULTICASTING
Modulation of orbital angular momentum on the propagation dynamics of light fields
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作者 Peng LI Sheng LIU +6 位作者 Yi ZHANG Lei HAN Dongjing WU Huachao CHENG Shuxia QI Xuyue GUO Jianlin ZHAO 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期69-87,共19页
Optical vortices carrying orbital angular momentum(OAM)have attracted extensive attention in recent decades because of their interesting applications in optical trapping,optical machining,optical communication,quantum... Optical vortices carrying orbital angular momentum(OAM)have attracted extensive attention in recent decades because of their interesting applications in optical trapping,optical machining,optical communication,quantum information,and optical microscopy.Intriguing effects induced by OAMs,such as angular momentum conversion,spin Hall effect of light(SHEL),and spin– orbital interaction,have also gained increasing interest.In this article,we provide an overview of the modulations of OAMs on the propagation dynamics of scalar and vector fields in free space.First,we introduce the evolution of canonical and noncanonical optical vortices and analyze the modulations by means of local spatial frequency.Second,we review the Pancharatnam–Berry(PB)phases arising from spin–orbital interaction and reveal the control of beam evolution referring to novel behavior such as spindependent splitting and polarization singularity conversion.Finally,we discuss the propagation and focusing properties of azimuthally broken vector vortex beams. 展开更多
关键词 ORBITAL ANGULAR MOMENTUM POLARIZATION SPIN ANGULAR MOMENTUM Pancharatnam-Berry (PB) phase ANGULAR DIFFRACTION
Origin of the anomalous trends in band alignment of GaX/ZnGeX2 (X = N, P, As, Sb) heterojunctions 预览
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作者 Ruyue Cao Hui-Xiong Deng +1 位作者 Jun-Wei Luo Su-Huai Wei 《半导体学报:英文版》 EI CAS CSCD 2019年第4期17-21,共5页
Utilizing first-principles band structure method, we studied the trends of electronic structures and band offsets of the common-anion heterojunctions GaX/ZnGeX2 (X = N, P, As, Sb). Here, ZnGeX2 can be derived by atomi... Utilizing first-principles band structure method, we studied the trends of electronic structures and band offsets of the common-anion heterojunctions GaX/ZnGeX2 (X = N, P, As, Sb). Here, ZnGeX2 can be derived by atomic transmutation of two Ga atoms in GaX into one Zn atom and one Ge atom. The calculated results show that the valence band maximums (VBMs) of GaX are always lower in energy than that of ZnGeX2, and the band offset decreases when the anion atomic number increases. The conduction band minimums (CBMs) of ZnGeX2 are lower than that of GaX for X = P, As, and Sb, as expected. However, surprisingly, for ZnGeN2, its CBM is higher than GaN. We found that the coupling between anion p and cation d states plays a decisive role in determining the position of the valence band maximum, and the increased electronegativity of Ge relative to Ga explains the lower CBMs of ZnGeX2 for X = P, As, and Sb. Meanwhile, due to the high ionicity, the strong coulomb interaction is the origin of the anomalous behavior for nitrides. 展开更多
关键词 GaX/ZnGeX2 HETEROJUNCTIONS band OFFSETS ATOMIC ORBITAL coupling
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Detection of photonic orbital angular momentum with micro- and nano-optical structures
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作者 Chenhao WAN Guanghao RUI +1 位作者 Jian CHEN Qiwen ZHAN 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期88-96,共9页
Light with an optical orbital angular momentum(OAM)has attracted an increasing amount of interest and has found its way into many disciplines ranging from optical trapping,edge-enhanced microscopy,high-speed optical c... Light with an optical orbital angular momentum(OAM)has attracted an increasing amount of interest and has found its way into many disciplines ranging from optical trapping,edge-enhanced microscopy,high-speed optical communication,and secure quantum teleportation to spin-orbital coupling.In a variety of OAM-involved applications,it is crucial to discern different OAM states with high fidelity.In the current paper,we review the latest research progress on OAM detection with micro-and nano-optical structures that are based on plasmonics,photonic integrated circuits(PICs),and liquid crystal devices.These innovative OAM sorters are promising to ultimately achieve the miniaturization and integration of high-fidelity OAM detectors and inspire numerous applications that harness the intriguing properties of the twisted light. 展开更多
关键词 orbital angular momentum (OAM) optical VORTICES singular optics spatial light MODULATOR surface PLASMON POLARITON (SPP) HOLOGRAPHY PHOTONIC integrated circuit (PIC)
Orbital cyclicity in sedimentary sequence and climatic indications of C-O isotopes from Lower Cretaceous in Qingxi Sag,Jiuquan Basin,NW China 预览
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作者 Siding Jin Haiyang Cao +2 位作者 Hua Wang Michael Wagreich Sylvain Richoz 《地学前缘:英文版》 CAS CSCD 2019年第2期467-479,共13页
Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag,Jiuquan Basin(NW China).Zircon U-Pb ages of the dated basalts at the top of th... Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag,Jiuquan Basin(NW China).Zircon U-Pb ages of the dated basalts at the top of the Xiagou Formation give an isochron age of 115.6 Ma,and the sedimentation interval of the Xiagou Formation was speculated to range from about 125/124 Ma to 115 Ma based on paleontological research and stratigraphic correlation analysis.Here we use GR logging data as a palaeoenvironmental and palaeoclimatic proxy to conduct a detailed cyclostratigraphic study of five selected wells.Power spectra,evolutionary fast Fourier transformation and wavelet analysis all reveal significant sedimentary cycles in the Xiagou Formation.The ratios of cycle wavelengths in these stratigraphic units are 33.82 m:7.91 m:3.06 m:1.79 m,which is similar to the ratio of orbital targets of 20:5:2:1.The ratio of 20:5:2:1 is interpreted as Milankovitch cycles of 405 kyr long eccentricity,100 kyr short eccentricity,37 kyr obliquity,and 22 kyr precession cycles respectively.A high-resolution astronomical time scale is constructed by tuning the stratigraphy into target curves of orbital cycles respectively.Based on the astronomical time scale,the absolute ages of 55 samples were estimated,which are used for subsequent stable carbon and oxygen isotope stratigraphy analysis.The analysis results of the five studied wells in the Qingxi Sag indicate:(1)a negative trend ofδ13C values upwards in the Xiagou Formation,and(2)negativeδ18O values with a positive trend upwards.Both relatively heavy values and pronounced covariances ofδ13C values andδ18O values indicate an arid-evaporationcontrolled climate during the sedimentary period of the Lower Cretaceous Xiagou Formation,Qingxi Sag,Jiuquan Basin.Moreover,positive covariances of SQK1g2t3 indicate extremely high temperature,and negative covariances of SQK1g1 indicate a relatively low temperature. 展开更多
关键词 Jiuquan Basin Qingxi SAG Xiagou Formation ORBITAL CYCLICITY Stable ISOTOPE
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A New One-dimensional Complex Assembled by 4-Nitrobenzoic Acid and Bis(imidazol) Ligands:Syntheses, Structures and Theoretical Calculations 预览
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作者 李秀梅 潘亚茹 +2 位作者 刘博 周实 常鹰飞 《结构化学》 SCIE CAS CSCD 2019年第5期783-790,670共9页
A new Zn(Ⅱ)coordination polymer,[Zn(nba)2(mbix)]2n(1,Hnba=4-nitrobenzoic acid,mbix=1,3-bis(imidazol-1-ylmethyl)-benzene),was synthesized and characterized by elemental analyses,IR spectra,TG,fluorescence spectroscopy... A new Zn(Ⅱ)coordination polymer,[Zn(nba)2(mbix)]2n(1,Hnba=4-nitrobenzoic acid,mbix=1,3-bis(imidazol-1-ylmethyl)-benzene),was synthesized and characterized by elemental analyses,IR spectra,TG,fluorescence spectroscopy,single-crystal and powder X-ray diffractions.It belongs to the triclinic system,P1 space group,with a=9.341(2),b=13.029(3),c=23.660(6)A,α=99.603(6)°,β=90.461(6)°,γ=90.597(5)°,V=2838.9(12)?3 and Z=2.It shows one-dimensional chains which are further linked by C–H···O hydrogen bonds andπ-πstacking interactions to yield a three-dimensional supramolecular structure.In addition,the Natural Bond Orbital(NBO)was analyzed in using the PBE0/LANL2DZ method built in Gaussian 09 Program.The calculation results indicated obvious covalent interaction between the coordinated atoms and Zn(Ⅱ)ion. 展开更多
关键词 synthesis crystal structure 4-nitrobenzoic acid Zn(Ⅱ) complex natural BOND ORBITAL
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Diffraction of relativistic vortex harmonics with fractional average orbital angular momentum
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作者 李沙沙 沈百飞 +4 位作者 王文鹏 步志刚 张浩 张辉 翟树华 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第5期1-5,共5页
Vortex harmonics with fractional average orbital angular momentum are genera ted when a relativistic fractional vortex beam is incident on and reflected from an over-dense plane plasma target. A two-step model is pres... Vortex harmonics with fractional average orbital angular momentum are genera ted when a relativistic fractional vortex beam is incident on and reflected from an over-dense plane plasma target. A two-step model is presented to explain the far-field patterns of the harmonics. In the Erst step, a fundamental spot-shaped hole is produced during the hole-boring stage, and harmonics are genera ted simultaneously. In the second step, differen t oTder harmonics are diffracted by the hole and propagate to the far field. This process can be accurately described by the Fraunhofer diffraction theory. This work facilitates a basic recognition of fractional vortex beams. 展开更多
关键词 RELATIVISTIC VORTEX HARMONICS FRACTIONAL AVERAGE ORBITAL angular momentum RELATIVISTIC FRACTIONAL VORTEX
Twist-driven separation of p-type and n-type dopants in single-crystalline nanowires
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作者 Dong-Bo Zhang Xing-Ju Zhao +2 位作者 Gotthard Seifert Kinfai Tse Junyi Zhu 《国家科学评论:英文版》 CSCD 2019年第3期532-539,共8页
The distribution of dopants significantly influences the properties of semiconductors,yet effective modulation and separation of p-type and n-type dopants in homogeneous materials remain challenging,especially for nan... The distribution of dopants significantly influences the properties of semiconductors,yet effective modulation and separation of p-type and n-type dopants in homogeneous materials remain challenging,especially for nanostructures.Employing a bond orbital model with supportive atomistic simulations,we show that axial twisting can substantially modulate the radial distribution of dopants in Si nanowires(NWs)such that dopants of smaller sizes than the host atom prefer atomic sites near the NW core,while dopants of larger sizes are prone to staying adjacent to the NW surface.We attribute such distinct behaviors to the twist-induced inhomogeneous shear strain in NW.With this,our investigation on codoping pairs further reveals that with proper choices of codoping pairs,e.g.B and Sb,n-type and p-type dopants can be well separated along the NW radial dimension.Our findings suggest that twisting may lead to realizations of p–n junction configuration and modulation doping in single-crystalline NWs. 展开更多
关键词 TWIST CODOPING NANOWIRE generalized BLOCH theorem bond orbital theory
The role of cell mediated immunopathogenesis in thyroidassociated ophthalmopathy
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作者 Zhen-Mao Wang Zheng-Yan Wang Yan Lu 《国际眼科杂志:英文版》 SCIE CAS 2019年第7期1209-1214,共6页
Currently, thyroid-associated ophthalmopathy (TAO) lacks effective treatment due to our lack of clarity in its immunopathogenesis. Orbital fibroblasts play a key role in altering inflammation and immune response in TA... Currently, thyroid-associated ophthalmopathy (TAO) lacks effective treatment due to our lack of clarity in its immunopathogenesis. Orbital fibroblasts play a key role in altering inflammation and immune response in TAO, and are considered as the key target and effector cells in its pathogenesis. The orbit infiltrating CD34+ fibrocytes add on to the process by expressing high levels of autoantigens and inflammatory cytokines, while also differentiating into myofibroblasts or adipocytes. This review focuses on the role of orbital fibroblasts and CD34+ fibrocytes in the pathogenesis of TAO, highlighting the basis of emerging treatments. 展开更多
关键词 thyroid-associated OPHTHALMOPATHY ORBITAL FIBROBLAST FIBROCYTES IMMUNOPATHOGENESIS
Clinical outcome after orbital floor fracture reduction with special regard to patient's satisfaction
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作者 Stefan Hartwig Marie-Christine Nissen +4 位作者 Jan Oliver Voss Christian Doll Nicolai Adolphs Max Heiland Jan Dirk Raguse 《中华创伤杂志:英文版》 CAS CSCD 2019年第3期155-160,共6页
Purpose: Primary reconstruction via transconjunctival approach is a standardized treatment option for orbital floor fractures. The aim of this study was to compare the findings of specific ophthalmologic assessment wi... Purpose: Primary reconstruction via transconjunctival approach is a standardized treatment option for orbital floor fractures. The aim of this study was to compare the findings of specific ophthalmologic assessment with the patient's complaints after fracture reduction. Methods: A retrospective medical chart analysis was performed on patients who had undergone transconjunctival orbital floor fracture reduction for fracture therapy with resorbable foil (ethisorb sheet or polydioxanone foil). A follow-up assessment including ophthalmological evaluation regarding visual acuity (eye chart projector), binocular visual field screening (Bagolini striated glasses test) and diplopia (cover test, Hess screen test) was conducted. Additionally, a questionnaire was performed to assess patients' satisfaction. Results: A total of 53 patients with a mean follow-up of 23 months (ranging from 11 to 72) after surgical therapy were included. Diplopia was present preoperatively in 23 (43.4%) and reduced in follow-up examination (n = 12, 22.6%). Limitations in ocular motility reduced from 37.7% to 7.5%. The questionnaire about the patient's satisfaction revealed excellent outcomes in relation to the functional and esthetical parameters. Conclusion: Transconjunctival approach is a safe approach for orbital fracture therapy. Postoperative diplopia is nearly never perceptible for the individual and differs to pathologic findings in the ophthalmic assessment. 展开更多
关键词 ORBITAL FLOOR FRACTURES BLOW out FRACTURES Transconjunctival approach Clinical OUTCOME
超声造影在眼眶占位性病变诊断中的应用 预览
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作者 张瑶 陈文卫 《临床超声医学杂志》 CSCD 2019年第2期124-126,共3页
超声造影能实时显示病灶内部血流及微循环状况,在肿块的鉴别诊断及引导穿刺活检等方面应用较多。近年来,超声造影逐渐应用于眼眶占位性病变的诊断和鉴别诊断,本文就超声造影在眼眶占位性病变诊断及鉴别诊断中的应用进行综述。
关键词 超声检查 造影剂 眼眶 占位性病变
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An improved frequency shift method for ATI-SAR flat earth phase removal 预览
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作者 Yubin Zhang Jie Zhang +1 位作者 Junmin Meng Chenqing Fan 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期94-100,共7页
An improved frequency shift method is proposed to remove the flat earth phase in ATI-SAR ocean surface motion detection in this study. First, two conventional flat earth effect removal methods(i.e., the frequency shif... An improved frequency shift method is proposed to remove the flat earth phase in ATI-SAR ocean surface motion detection in this study. First, two conventional flat earth effect removal methods(i.e., the frequency shift method and the orbital parameter method) are introduced and compared. Then, two improvements to frequency shift method are suggested. In the first improvement, the phase diagram is divided into several sub-blocks to calculate the phase fringe frequency. In the second improvement, a function between the phase of land regions and position is fitted to correct the residual flat earth phase based on the phase of the land regions that tend toward zero in an along-track interferogram. It is found that the improved frequency shift method is greatly improved;and it agrees well with the orbital parameter method, and achieves similar accuracy. 展开更多
关键词 FLAT EARTH PHASE ATI-SAR frequency SHIFT ORBITAL PARAMETER
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DFT Studies on the Stoichiometric Thorium Oxide Clusters(ThO2)n(n = 1~5): Electronic and Structural Properties 预览
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作者 夏婵娟 汪玲妃 +1 位作者 黄昕 王彬 《结构化学》 SCIE CAS CSCD 2019年第7期1053-1068,共16页
Density functional theory(DFT) calculations are performed to investigate the electronic and structural properties of the stoichiometric thorium oxide clusters(ThO2)n-/0(n = 1~5). Generalized Koopmans' theorem is a... Density functional theory(DFT) calculations are performed to investigate the electronic and structural properties of the stoichiometric thorium oxide clusters(ThO2)n-/0(n = 1~5). Generalized Koopmans' theorem is applied to predict the vertical detachment energies(VDEs)which are used to simulate the anionic photoelectron spectra(PES). Molecular orbital analyses are performed as well to analyze the chemical bonding in these thorium oxide clusters. The results show that the ground states of(ThO2)_n-/0(n = 1~5) clusters prefer the low-spin structures. With increasing of the cluster size(n), the structure parameters of(ThO2)n-/0(n = 1~5) gradually evolve toward bulk thorium oxide species. It shows that both the coordination number and the average bond length increase gradually in(ThO2)n-/0(n = 1~5) to approach that of ThO2 bulk. What's more, the vibration frequencies of Th=O double bonds are found to be decreasing along with the increased cluster size. 展开更多
关键词 density functional theory THORIUM oxide ELECTRONIC structure simulated PHOTOELECTRON spectroscopy molecular ORBITAL
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Exploring the effect of aggregation-induced emission on the excited state intramolecular proton transfer for a bis-imine derivative by quantum mechanics and our own n-layered integrated molecular orbital and molecular mechanics calculations
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作者 赵慧芳 孙朝范 +2 位作者 刘晓春 尹航 石英 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期645-649,共5页
We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonometh... We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the 'our own n-layered integrated molecular orbital and molecular mechanics'(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds. 展开更多
关键词 time-dependent density functional theory(TDDFT) METHOD excited state intramolecular proton transfer(ESIPT) our own n-layered integrated MOLECULAR orbital and MOLECULAR mechanics(ONIOM) METHOD potential energy curves atomic dipole moment corrected Hirshfeld population(ADCH) charge
因角膜异物而漏诊眼内和眶内异物的原因分析
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作者 刘秀云 张志勇 《中华眼外伤职业眼病杂志》 2019年第4期253-257,共5页
目的分析因角膜表面铁质异物而被漏诊眼内和眶内异物的原因。方法回顾性分析2018年2月至11月我院就诊被漏诊眼内和眶内异物的角膜铁质异物剔除术后6例(6只眼)的临床资料。结果本组初诊时均未接受CT、X线和UBM检查,其中5例未接受B超检查... 目的分析因角膜表面铁质异物而被漏诊眼内和眶内异物的原因。方法回顾性分析2018年2月至11月我院就诊被漏诊眼内和眶内异物的角膜铁质异物剔除术后6例(6只眼)的临床资料。结果本组初诊时均未接受CT、X线和UBM检查,其中5例未接受B超检查,初诊均未发现角膜、虹膜或巩膜的细小穿孔和眼内眶内异物。6例角膜浅层异物接受角膜异物剔除术后出现并发症,通过CT、X线、B超和UBM检查后确诊眼内或眶内异物。结论角膜表面的铁质异物可能并发眼内或眶内异物,漏诊可导致严重的眼部并发症,细致的眼部检查,并辅以CT、X线、B超和UBM检查能减少漏诊。 展开更多
关键词 眼异物 角膜 眼眶
眼眶炎性假瘤的CT诊断及鉴别诊断 预览
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作者 孙大量 柴昌 《现代医用影像学》 2019年第3期527-528,共2页
目的:本文探究CT应用在眼眶炎性假瘤患者中所取得的诊断效果,对CT应用在眼眶炎性假瘤患者的诊断价值展开评价。方法:本次于2017年10月-2018年10月选取25例眼眶炎性假瘤患者纳入研究之内,患者均接受CT检查,回顾性患者的临床资料和诊断结... 目的:本文探究CT应用在眼眶炎性假瘤患者中所取得的诊断效果,对CT应用在眼眶炎性假瘤患者的诊断价值展开评价。方法:本次于2017年10月-2018年10月选取25例眼眶炎性假瘤患者纳入研究之内,患者均接受CT检查,回顾性患者的临床资料和诊断结果。结果:在本次的检查之中,患者眼球均突出。肌炎型共10例(40.0%),眼外肌受累增粗且肌腱肥大,边缘毛糙,起肌腱止点处出现增粗,其中共3例患者外直肌增粗,内直肌增粗共6例,4例为上直肌增粗,7例为外直肌肉增粗,伴神经增粗共1例,2例患者伴眼球壁增厚;肿块型共3例(12.0%),患者眶内软组织肿块;弥漫型共2例(8.0%),充满眶内球后脂肪间隙密度出现增高,肌锥内脂肪间隙呈现不规则的条片高密度影,软组织且结构分解不清;混合型共9例(36.0%),眼外肌增粗并且合并周围脂肪密度增高,肿块合并眼外肌增粗,肿大泪腺合并相邻外直肌增粗,伴视神经增粗共3例,伴眼球壁增厚共2例;泪腺型共1例(4.0%),泪腺增大呈现处肿块,其中1例为不规则形,2例为蚕豆型。有9例患者出现了眼环增厚、神经增粗、病变出现不同程度的强化,并且伴有鼻窦炎。结论:眼眶炎性假瘤患者应用CT检查,可取得良好的诊断效果。CT检查在临床中较高的准确率,可对患者的眼眶炎性假瘤分型状况进行更为全面、准确的评价,有利于医师根据分型制定治疗方案,有利于改善患者的预后,值得推广。 展开更多
关键词 眼眶 X线计算机 炎性假瘤 CT 检测
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Theoretical analyses of chemical bonding in terminal EThF2 (E = O, S, Se, Te) 预览
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作者 Yan-Li Li Xiao-Gen Xiong Hong-Tao Liu 《核技术:英文版》 SCIE CAS CSCD 2019年第5期1-8,共8页
Analyses of chemical bonding and geometric structures in species with chalcogen elements EThF2 (E = O, S, Se, Te) are performed by the density functional theory. Kohn–Sham molecular orbitals and Th–E bond lengths of... Analyses of chemical bonding and geometric structures in species with chalcogen elements EThF2 (E = O, S, Se, Te) are performed by the density functional theory. Kohn–Sham molecular orbitals and Th–E bond lengths of these species both indicate multiple bond character for the terminal chalcogen complexes. This is also confirmed by natural bond orbital analyses using the oneelectron density matrix generated by relativistic density functional calculations. Theoretical analyses indicate that electron donation from E to Th increases down the chalcogen group (O<S<Se<Te). These molecules can serve as examples of multiple bonding between actinide elements and selenium or tellurium. 展开更多
关键词 EThF2 Chemical BONDING Natural BOND ORBITAL (NBO)
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Aperture efficiency and mode constituent analysis for OAM vortex beam generated by digital metasurface
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作者 张迪 曹祥玉 +2 位作者 杨欢欢 高军 吕世奇 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期185-191,共7页
A systematic study of the aperture efficiency and mode constituent for orbital angular momentum(OAM) vortex beam generated by digital metasurface is presented. The aperture efficiency and OAM spectrum are computed for... A systematic study of the aperture efficiency and mode constituent for orbital angular momentum(OAM) vortex beam generated by digital metasurface is presented. The aperture efficiency and OAM spectrum are computed for different bit numbers. It is found that the aperture efficiency declines for digital metasurface due to the phase quantization error,especially for 1-bit device. Fortunately, the OAM spectrum is barely affected by phase quantization and the designated main mode keeps dominant for different bit numbers, indicating that high purity OAM vortex beam can be generated by digital metasurface. Besides, the influence of topological charge l is also investigated. For a fixed metasurface, the radiation performance deteriorates sharply with the growing of l and the parasitic OAM mode becomes dominant at certain angle.At last, a prototype of 1-bit metasurface was simulated, fabricated and measured in anechoic chamber. The simulation and experiment results verify the correctness of the numerical analysis. 展开更多
关键词 ORBITAL ANGULAR momentum(OAM) efficiency MODE CONSTITUENT metasurface
Two New Zn(Ⅱ) and Co(Ⅱ) Coordination Polymers Constructed by 4-Bromobenzoic Acid and 1,4-Bis(imidazol-1-yl)-butane: Synthesis, Crystal Structure and Theoretical Calculations 预览
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作者 潘亚茹 李秀梅 +2 位作者 刘博 周实 常鹰飞 《结构化学》 SCIE CAS CSCD 2019年第4期635-643,共9页
Two new coordination polymers, [Zn(bba)2(bib)]2n(1) and [Co0.5(bba)(bib)0.5]2n(2)(Hbba = 4-bromobenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane), have been hydrothermally designed and synthesized, and their structur... Two new coordination polymers, [Zn(bba)2(bib)]2n(1) and [Co0.5(bba)(bib)0.5]2n(2)(Hbba = 4-bromobenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane), have been hydrothermally designed and synthesized, and their structures were determined by elemental analyses, IR spectroscopy, TG, fluorescence spectroscopy, X-ray single-crystal and powder diffraction. Complexes 1 and 2 both belong to the monoclinic system and exhibit one-dimensional zigzag chain-like structure. In addition, we analyzed Natural Bond Orbital(NBO) in using the PBE0/LANL2 DZ method built in Gaussian 03 Program. The calculation results indicated the obvious covalent interaction between the coordinated atoms and Zn(Ⅱ), Co(Ⅱ) ions. 展开更多
关键词 SYNTHESIS crystal structure Zn(Ⅱ) COMPLEX Co(Ⅱ) COMPLEX natural bond orbital
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