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Inverted T-Shaped Flap Nursing after the Reverse Double V-Shaped Mastoconstriction Suspension for Breast Cancer 被引量:1
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作者 Linfei Liu Lijuan Zhang +2 位作者 Yuanzhen Luo Xuehui Zeng Rong Chen 《Advances in Breast Cancer Research》 2021年第4期165-172,共8页
<strong>Objective:</strong> <span style="font-family:""><span style="font-family:Verdana;">To explore the inverted T-shaped flap nursing after breast-conserving surgery... <strong>Objective:</strong> <span style="font-family:""><span style="font-family:Verdana;">To explore the inverted T-shaped flap nursing after breast-conserving surgery combined with the reverse double V-shaped mastoconstriction suspension for breast cancer, and summarizes the nursing methods and experience. </span><b><span style="font-family:Verdana;">Method: </span></b><span style="font-family:Verdana;">5 patients who underwent reverse double V-shaped mastoconstriction suspension and formed inverted T-shaped flap incision were selected from the same medical group in the Department of Breast Cancer of Sun Yat-sen University’s Cancer Center from February 1, 2019 to April 30, 2019, and they were evaluated for the recovery of blood supply of skin flap, sensory function of nipple and areola, breast satisfaction, etc. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">Among the 5 patients in this group, the flaps of them all survived smoothly. The one-year follow-up after the operation showed that they were satisfied with the appearance of the breast after the operation, with normal sensory function, and no secondary sagging. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The most important thing about the </span><a name="_Hlk80007513"></a><span style="font-family:Verdana;">inverted T-shaped flap after the reverse double V-shaped mastoconstriction suspension for breast cancer is the blood supply. Close observation of the condition of the skin flap after the operation, strengthening the care of the skin flap, and preventing infection are the keys to the success of the operation.</span></span> 展开更多
关键词 Breast Cancer Breast Conservation Mastoconstriction Suspension flap Nursing
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Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil
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作者 Yuanjun Dai Jingan Cui +2 位作者 Baohua Li Cong Wang Kunju Shi 《Fluid Dynamics & Materials Processing》 EI 2024年第4期771-786,共16页
A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coeffici... A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag coefficient.The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly reduced.When the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very evident.As the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake vortex.Optimal aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced. 展开更多
关键词 AIRFOIL flap height flap angle lift-drag ratio aerodynamic characteristics
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Management of Square Carcinoma of the Lower Lip Using Camille-Bernard Flap under Local Anesthesia: When Constraints Dictate Our Attitude
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作者 Silly Toure Mouhamadou Makhtar Ndiaye +3 位作者 Abibou Ndiaye Mame Sanou Diouf Birame Loum Baye Karim Diallo 《Open Journal of Stomatology》 2024年第4期191-197,共7页
Introduction: Squamous cell carcinomas of the lip essentially pose a therapeutic management problem. In the West, their treatment is done under general anesthesia and follows the classic rules of oncology. In our cont... Introduction: Squamous cell carcinomas of the lip essentially pose a therapeutic management problem. In the West, their treatment is done under general anesthesia and follows the classic rules of oncology. In our context of exercise, we sometimes have a different attitude dictated by various constraints. Observation: 55-year-old patient with no notable history, seen in consultation for a very large ulcerative-budding lesion on the right 2/3 of the lower lip with mucocutaneous involvement without lymph node findings found on examination. Faced with this suspicious lesion and the patient’s financial difficulties, we decided to operate under local anesthesia to remove this tumor. The oncological excision was followed by immediate plasty using a Camille-Bernard flap with a good immediate aesthetic and functional result and postoperative day 7. The patient was unable to take his surgical specimen to anatomy-pathology and was lost to follow-up due to lack of financial resources. On anatomo-pathological analysis of the surgical specimen, the margins were healthy with confirmation of squamous cell carcinoma (anapathological reading made for scientific interest). Discussion: The particular mentality of certain patients and their difficult financial conditions push us to have an unconventional therapeutic attitude in oncology, but which nevertheless makes it possible to resolve certain problems that we often face. Local anesthesia is possible and realistic in cases like ours and the results can be acceptable and life-saving. 展开更多
关键词 Squamous Cell Carcinoma Lower Lip Camille Bernard flap Local Anesthesia
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Pedicled abdominal flap using deep inferior epigastric artery perforators for forearm reconstruction: A case report
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作者 Jae Hyung Jeon Kyung Wook Kim Hong Bae Jeon 《World Journal of Clinical Cases》 SCIE 2024年第4期828-834,共7页
BACKGROUND Pedicled abdominal flaps are a widely used surgical technique for forearm reconstruction in patients with soft tissue defects.However,some drawbacks include restricted flap size,partial flap loss,and donor-... BACKGROUND Pedicled abdominal flaps are a widely used surgical technique for forearm reconstruction in patients with soft tissue defects.However,some drawbacks include restricted flap size,partial flap loss,and donor-site morbidity.To address these concerns,we present a case of a pedicled abdominal flap using the deep inferior epigastric artery perforators(DIEP)for forearm reconstruction in a patient with a large soft tissue defect.CASE SUMMARY A 46-year-old male patient was admitted to our hospital with forearm injury caused by a pressing machine.A 15 cm×10 cm soft tissue defect with complete rupture of the ulnar side structures of the forearm was found.One week after orthopedic management of the neurovascular injury and fractures using the first stage of Masquelet technique,the patient was referred to the plastic and recon-structive surgery department for wound coverage.Surgical debridement and negative-pressure wound therapy revealed a 20 cm×15 cm soft tissue defect.A pedicle abdominal flap with the DIEP was used to cover the defect.Three weeks later,the flap was detached from the abdomen,and the abdominal defect was directly closed.Subsequently,the second stage of Masquelet technique was performed at the fracture site at week 10.Finally,all donor and recipient sites healed without complications,such as flap dehiscence,infection,hematoma,or necrosis.Fracture site osteosynthesis was achieved without complications.CONCLUSION Pedicled abdominal flap using the DIEP provides a reliable option for forearm reconstruction in patients with large soft tissue defects. 展开更多
关键词 Forearm injury Open fracture reduction Perforator flap Deep inferior epigastric artery perforators Case report
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Thrust Optimization of Flapping Wing via Gradient Descent Technologies
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作者 Jeshwanth Kundem 《Open Journal of Fluid Dynamics》 2024年第2期83-99,共17页
The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flo... The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed. 展开更多
关键词 Steepest Descent CFD flapping Wing Airfoil Thrust Performance
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Sternocleidomastoid flap for reconstruction of tongue small cell carcinoma: A case report
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作者 Hendry Irawan Made Bagus Sastrapramaya Bharata 《World Journal of Surgical Procedures》 2024年第2期8-14,共7页
BACKGROUND The management of tongue carcinoma is excision and radical neck dissection followed with reconstruction.This is a case report of a patient with tongue squamous cell carcinoma(SCC)who underwent the procedure... BACKGROUND The management of tongue carcinoma is excision and radical neck dissection followed with reconstruction.This is a case report of a patient with tongue squamous cell carcinoma(SCC)who underwent the procedure with sternocleidomastoid(SCM)flap reconstruction.CASE SUMMARY A 52-year-old woman without smoking history complained tongue ulcer since 3 years ago.Based on the histopathological examination,the patient was diagnosed with T2N2M0 right tongue SCC and underwent wide excision of tumor;right mandibular;neck dissection and were reconstructed with SCM flap.CONCLUSION SCC of the tongue requires wide excision and dissection of the neck and mandible if infiltration into the surrounding lymph nodes has been found.The SCM flap reconstruction could be used post-surgery. 展开更多
关键词 Sternocleidomastoid flap Neck dissection Mandibular dissection Squamous cell carcinoma of the tongue Case report
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V-Shaped Monopole Antenna with Chichena Itzia Inspired Defected Ground Structure for UWB Applications 被引量:7
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作者 Naeem Ahmad Jan Saad Hassan Kiani +4 位作者 Fazal Muhammad Daniyal Ali Sehrai Amjad Iqbal Muhammad Tufail Sunghwan Kim 《Computers, Materials & Continua》 SCIE EI 2020年第10期19-32,共14页
Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distor... Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distortion losses is desired.In this paper,a compact Ultra-Wideband(UWB)V-shaped monopole antenna is presented.UWB response is achieved by modifying the ground plane with Chichen Itzia inspired rectangular staircase shape.The proposed V-shaped is designed by incorporating a rectangle,and an inverted isosceles triangle using FR4 substrate.The size of the antenna is 25 mm×26 mm×1.6 mm.The proposed V-shaped monopole antenna produces bandwidth response of 3 GHz Industrial,Scientific,and Medical(ISM),Worldwide Interoperability for Microwave Access(WiMAX),(IEEE 802.11/HIPERLAN band,5G sub 6 GHz)which with an additional square cut amplified the bandwidth response up to 8 GHz ranging from 3.1 GHz to 10.6 GHz attaining UWB defined by Federal Communications Commission(FCC)with a maximum gain of 3.83 dB.The antenna is designed in Ansys HFSS.Results for key performance parameters of the antenna are presented.The measured results are in good agreement with the simulated results.Due to flat gain,uniform group delay,omni directional radiation pattern characteristics and well-matched impedance,the proposed antenna is suitable for WiMAX,ISM and heterogeneous wireless systems. 展开更多
关键词 v-shape MONOPOLE GAIN STAIRCASE ULTRA-WIDEBAND OMNI-DIRECTIONAL defected ground structure
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RIGID-PLASTIC MECHANICAL MODEL FOR THE FORGING METHOD WITH HORIZONTAL V-SHAPED ANVIL 被引量:6
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作者 LIU Zhubai NI Liyong +2 位作者 LIU Guohui ZHANG Yongjun ZHU Wenbo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第2期272-275,共4页
In order to decrease the anisotropy of mechanical properties, the rigid-plastic mechanical model for the forging method with horizontal V-shaped anvil is presented. The forging method, through the change of anvils sha... In order to decrease the anisotropy of mechanical properties, the rigid-plastic mechanical model for the forging method with horizontal V-shaped anvil is presented. The forging method, through the change of anvils shape, is able to control fibrous tissue direction, to improve the anisotropy of mechanical properties of axial forgings, to realize uniform forging. Therefore, the forging method can overcome the defect that conventional forging methods produce. The mechanism of the forging method with horizontal V-shaped anvil and the process of metal deformation are analyzed. The agreement of theoretical analysis with experimental study verifies the fact that the forging method with horizontal V-shaped anvil can control effectively the mechanical properties of axial forgings. 展开更多
关键词 FORGING HORIZONTAL v-shaped anvil Axial forging ANISOTROPY Tissue flow direction
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An experimental investigation of the fracturing behaviour of rock-like materials containing two V-shaped parallelogram flaws 被引量:8
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作者 Jinjin Tian Dongjing Xu Tianhao Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期777-783,共7页
The distribution characteristics and evolution law of rock mass fissures induced by mining are a key scientific issue in the study of deep rock mechanics.In this study,a series of uniaxial compression experiments was ... The distribution characteristics and evolution law of rock mass fissures induced by mining are a key scientific issue in the study of deep rock mechanics.In this study,a series of uniaxial compression experiments was conducted on rock-like specimens containing double V-shaped prefabricated fissures at dip angles ofα=β=45°,α=45°<b=60°,α=β=60°,andα=60°<β=75°with a rock mechanics servocontrolled testing system.According to the experimental results,the effects of the dip angles of the double V-shaped prefabricated flaws with the same area on the mechanical parameters and fracturing process of the specimens were analysed in detail.Additionally,the crack initiation stress presented a nearly linear growth trend,which is generally similar to that of the crack peak stress with increasing flaw dip angle.By applying photographic monitoring to the crack initiation,propagation,coalescence,and failure modes in rock-like specimens,it was easily seen that the V-shaped flaw properties slightly influence the crack initiation positions but significantly influence the crack trajectories.The crack failure modes can be summarized into two distinct types.The study reported herein can provide a better understanding of the evolution of double V-shaped prefabricated fissures induced by coal mining. 展开更多
关键词 v-shaped fissure Fracturing process Overburden strata Coal mining
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Scattering of SH waves induced by a symmetrical V-shaped canyon: a unified analytical solution 被引量:20
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作者 Zhang Ning Gao Yufeng +2 位作者 Li Dayong Wu Yongxin Zhang Fei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第4期445-460,共16页
This paper reports a series solution of wave functions for two-dimensional scattering and diffraction of plane SH waves induced by a symmetrical V-shaped canyon with different shape ratios. A half-space with a symmetr... This paper reports a series solution of wave functions for two-dimensional scattering and diffraction of plane SH waves induced by a symmetrical V-shaped canyon with different shape ratios. A half-space with a symmetrical V-shaped canyon is divided into two sub-regions by using a circular-arc auxiliary boundary. The two sub-regions are represented by global and local cylindrical coordinate systems, respectively. In each coordinate system, the wave field satisfying the Helmholtz equation is represented by the separation of variables method, in terms of the series of both Bessel functions and Hankel functions with unknown complex coefficients. Then, the two wave fields are described in the local coordinate system using the Graf addition theorem. Finally, the unknown coefficients are sought by satisfying the continuity conditions of the auxiliary boundary. To consider the phase characteristics of the wave scattering, a parametric analysis is carried out in the time domain by assuming an incident signal of the Ricker type. Surface and subsurface transient responses demonstrate the characteristics and mechanisms of wave propagating and scattering. 展开更多
关键词 SH-wave scattering v-shaped canyon topographic effect wave propagation earthquake ground motion wave function expansion method
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Seismic analysis of high-speed railway irregular bridge–track system considering V-shaped canyon effect 被引量:4
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作者 Zhihui Zhu Yongjiu Tang +2 位作者 Zhenning Ba Kun Wang Wei Gong 《Railway Engineering Science》 2022年第1期57-70,共14页
To explore the effect of canyon topography on the seismic response of railway irregular bridge-track system that crosses a V-shaped canyon, seismic ground motions of the horizontal site and V-shaped canyon site were s... To explore the effect of canyon topography on the seismic response of railway irregular bridge-track system that crosses a V-shaped canyon, seismic ground motions of the horizontal site and V-shaped canyon site were simulated through theoretical analysis with 12 earthquake records selected from the Pacific Earthquake Engineering Research Center(PEER) Strong Ground Motion Database matching the site condition of the bridge.Nonlinear seismic response analyses of an existing 11-span irregular simply supported railway bridge-track system were performed under the simulated spatially varying ground motions. The effects of the V-shaped canyon topography on the peak ground acceleration at bridge foundations and seismic responses of the bridge-track system were analyzed. Comparisons between the results of horizontal and V-shaped canyon sites show that the top relative displacement between adjacent piers at the junction of the incident side and the back side of the V-shaped site is almost two times that of the horizontal site, which also determines the seismic response of the fastener. The maximum displacement of the fastener occurs in the V-shaped canyon site and is 1.4 times larger than that in the horizontal site. Neglecting the effect of V-shaped canyon leads to the inappropriate assessment of the maximum seismic response of the irregular high-speed railway bridge-track system. Moreover, engineers should focus on the girder end to the left or right of the two fasteners within the distance of track seismic damage. 展开更多
关键词 v-shaped canyon Nonlinear seismic response Irregular bridge Simply supported railway bridge Analytical solution Topography effect
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New Methods of Determining the Mixed Mode Stress Intensity Factors for V-Shaped Notch
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作者 Lin Zhong-qin Yu Haiyan Chen Guanlong Li Shu-hui 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期188-193,共6页
In this paper, on the basis of the stress field given by D.H.Chen, three new photoelastic methods are developed for determining the stress intensity factors K1 and K2 of V-shaped notch. Some photoelastic experiments a... In this paper, on the basis of the stress field given by D.H.Chen, three new photoelastic methods are developed for determining the stress intensity factors K1 and K2 of V-shaped notch. Some photoelastic experiments are performed on a skew -symmetric 45° notch. Measurements of the coordinates components of r,θand fringe order N are made for progressively smaller fringes and used in the proposed methods to solve K1 and K2.Plots of apparent K vs. r/l are made and extrapolated to the notch tip to yield the true values of K1 and K2.The results obtained by the three methods are very close to each other. When the notch problem is simplified as a crack problem, the corresponding equation is identical to the one proposed by D.G. Smith, which shows that the proposed methods are applicable for both notch and crack problems. 展开更多
关键词 photoelastic stress INTENSITY factors ISOCHROMATIC FRINGE v-shaped NOTCH
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Light-extraction efficiency and forward voltage in GaN-based light-emitting diodes with different patterns of V-shaped pits
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作者 王敏帅 黄晓菁 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期547-550,共4页
We present a new method of making a textured V-pit surface for improving the light extraction efficiency in GaN- based light-emitting diodes and compare it with the usual low-temperature method for p-GaN V-pits. Three... We present a new method of making a textured V-pit surface for improving the light extraction efficiency in GaN- based light-emitting diodes and compare it with the usual low-temperature method for p-GaN V-pits. Three types of GaNbased light-emitting diodes (LEDs) with surface V-pits in different densities and regions were grown by metal-organic chemical vapor deposition. We achieved the highest output power and lowest forward voltage values with the p-InGaN V-pit LED. The V-pits enhanced the light output power values by 1.45 times the values of the conventional LED owing to an enhancement of the light scattering probability and an effective reduction of Mg-acceptor activation energy. Moreover, this new technique effectively solved the higher forward voltage problem of the usual V-pit LED. 展开更多
关键词 v-shaped pits light-extraction efficiency forward voltage
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Wave Pressure Acting on V-Shaped Floating Breakwater in Random Seas
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作者 YU Yang DING Ning +1 位作者 LIN Jie HOU Jiajia 《Journal of Ocean University of China》 SCIE CAS 2015年第6期975-981,共7页
Wave pressure on the wet surface of a V-shaped floating breakwater in random seas is investigated. Considering the diffraction effect, the unit velocity potential caused by the single regular waves around the breakwat... Wave pressure on the wet surface of a V-shaped floating breakwater in random seas is investigated. Considering the diffraction effect, the unit velocity potential caused by the single regular waves around the breakwater is solved using the finite-depth Green function and boundary element method, in which the Green function is solved by integral method. The Response-Amplitude Operator(RAO) of wave pressure is acquired according to the Longuet-Higgins' wave model and the linear Bernoulli equation. Furthermore, the wave pressure's response spectrum is calculated according to the wave spectrum by discretizing the frequency domain. The wave pressure's characteristic value corresponding to certain cumulative probability is determined according to the Rayleigh distribution of wave heights. The numerical results and field test results are compared, which indicates that the wave pressure calculated in random seas agrees with that of field measurements. It is found that the bigger angle between legs will cause the bigger pressure response, while the increase in leg length does not influence the pressure significantly. The pressure at the side of head sea is larger than that of back waves. When the incident wave angle changes from 0? to 90?, the pressure at the side of back waves decreases clearly, while at the side of head sea, the situation is more complicated and there seems no obvious tendency. The concentration of wave energy around low frequency(long wavelength) will induce bigger wave pressure, and more attention should be paid to this situation for the structure safety. 展开更多
关键词 RANDOM SEAS v-shaped FLOATING BREAKWATER wave pressure boundary element method spectrum analysis
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Electronic and transport properties of V-shaped defect zigzag MoS_2 nanoribbons
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作者 李新梅 龙孟秋 +2 位作者 崔丽玲 肖金 徐慧 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期557-561,共5页
Based on the nonequilibrium Green's function (NEGF) in combination with density functional theory (DFT) calcu- lations, we study the electronic structures and transport properties of zigzag MoS2 nanoribbons (ZM... Based on the nonequilibrium Green's function (NEGF) in combination with density functional theory (DFT) calcu- lations, we study the electronic structures and transport properties of zigzag MoS2 nanoribbons (ZMNRs) with V-shaped vacancy defects on the edge. The vacancy formation energy results show that the zigzag vacancy is easier to create on the edge of ZMNR than the armchair vacancy. Both of the defects can make the electronic band structures of ZMNRs change from metal to semiconductor. The calculations of electronic transport properties depict that the currents drop off clearly and rectification ratios increase in the defected systems. These effects would open up possibilities for their applications in novel nanoelectronic devices. 展开更多
关键词 transport property zigzag MoS2 nanoribbons v-shaped defect FIRST-PRINCIPLES
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Construction of a 3D Co(Ⅱ) Framework Based on Two Types of V-shaped Bidentate Ligands
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作者 胡劲松 张雷 +2 位作者 石建军 邢宏龙 何杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第4期579-584,共6页
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and w... A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with α = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied. 展开更多
关键词 coordination polymer v-shaped ligand CRYSTAL STRUCTURE UV-vis spectrum
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Carrier transport via V-shaped pits in InGaN/GaN MQW solar cells
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作者 刘诗涛 全知觉 王立 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期558-563,共6页
Carrier transport via the V-shaped pits (V-pits) in InGaN/GaN multiple-quantum-well (MQW) solar cells is numer- ically investigated. By simulations, it is found that the V-pits can act as effective escape paths fo... Carrier transport via the V-shaped pits (V-pits) in InGaN/GaN multiple-quantum-well (MQW) solar cells is numer- ically investigated. By simulations, it is found that the V-pits can act as effective escape paths for the photo-generated carriers. Due to the thin barrier thickness and low indium composition of the MQW on V-pit sidewall, the carriers entered the sidewall QWs can easily escape and contribute to the photocurrent. This forms a parallel escape route for the carries generated in the fiat quantum wells. As the barrier thickness of the fiat MQW increases, more carriers would transport via the V-pits. Furthermore, it is found that the V-pits may reduce the recombination losses of carriers due to their screening effect to the dislocations. These discoveries are not only helpful for understanding the carrier transport mechanism in the InGaN/GaN MQW, but also important in design of the structure of solar cells. 展开更多
关键词 v-shaped pits InGaN/GaN multiple-quantum-well solar cells carrier transport
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Study on a W-band modified V-shaped microstrip meander-line traveling-wave tube
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作者 沈飞 魏彦玉 +3 位作者 许雄 殷海荣 宫玉彬 王文祥 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期239-244,共6页
The study on a miniaturized, low-voltage, wide-bandwidth, high-efficiency modified V-shaped microstrip meander-line slow-wave structure is presented. This structure is evolved from the original U-shaped microstrip mea... The study on a miniaturized, low-voltage, wide-bandwidth, high-efficiency modified V-shaped microstrip meander-line slow-wave structure is presented. This structure is evolved from the original U-shaped microstrip meander-line slow-wave structure, combining the advantages of a traditional microstrip and a rectangular helix. In this paper, simulations of the electromagnetic characteristics and the beam-wave interaction of this structure are carried out. Our study shows that when the design voltage and the current of a sheet electron beam are set to be 4700 V and 100 mA, respectively, this miniature millimeter-wave power amplifier is capable of delivering 160-W output power with a corresponding gain of 37.3 dB and a maximum interaction efficiency of 34% at 97 GHz. 展开更多
关键词 modified v-shaped microstrip meander-line millimeter-wave power amplifier beam-wave interaction slow-wave structure
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Construction of a 2D Cd(II) Coordination Polymer Based on a V-shaped Bidentate Ligand
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作者 张雷 胡劲松 何杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第9期1297-1302,共6页
A two-dimensional(2D)coordination polymer{[Cd(bdc)(dpb)]·H2O}n(1)has been prepared by solvothermal reaction of 1,3-dipyridyl benzene(1,3-dpb)with deprotonated1,4-benzenedicarboxylate(H2bdc),and was ch... A two-dimensional(2D)coordination polymer{[Cd(bdc)(dpb)]·H2O}n(1)has been prepared by solvothermal reaction of 1,3-dipyridyl benzene(1,3-dpb)with deprotonated1,4-benzenedicarboxylate(H2bdc),and was characterized by elemental analysis,IR spectroscopy,and X-ray single-crystal diffraction.It crystallizes in the monoclinic system,space group C2/c with a=15.1839(12),b=20.7585(17),c=7.2989(6),β=117.3450(10)°,V=2043.5(3)3,C24H18N2O5Cd,Mr=526.81,Dc=1.712 g/cm3,F(000)=1056.0,μ=1.110 mm-1and Z=4.The neighboring Cd(II)ions link the bdc2-anions and 1,3-dpb to form an infinite 2D sheet,and such two2D sheets are interlocked with each other to form a 2D→2D sheet.Two groups of interlocked sheets are further linked together by intermolecularπ···πinteraction,giving a 3D supramolecular network.In addition,the fluorescence property of 1 was also studied. 展开更多
关键词 coordination polymer v-shaped ligand crystal structure π···π interaction FLUORESCENCE
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Enhanced optical transmission by V-shaped nanoslit in metal film
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作者 贺梦冬 马旺国 王新军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期287-292,共6页
In this paper, we reveal that the enhanced transmission through a perforated metal film can be further boosted up by a V-shaped nanoslit, which consists of two connected oblique slits. The maximum transmission at reso... In this paper, we reveal that the enhanced transmission through a perforated metal film can be further boosted up by a V-shaped nanoslit, which consists of two connected oblique slits. The maximum transmission at resonance can be enhanced significantly by 71.5% in comparison with the corresponding vertical slit with the same exit width. The value and position of transmission resonance peak strongly depend on the apex angle of the V-shaped slit. The optimum apex angle, at which the transmission is maximal, is sensitive to the slit width. Such phenomena can be well explained by a concrete picture in which the incident wave drives free electrons on the slit walls. Moreover, we also simply analyze the splitting of the transmission peak in the symmetry broken V-shaped slit, originating from the resonances of different parts of the V-shaped slit. We expect that our findings will be used to design the nanoscale light sources based on the metal nanoslit structures. 展开更多
关键词 v-shaped nanoslit in metal film enhanced optical transmission surface plasmon polaritons
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