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Classification Criteria of Narrow/Wide Ice-ResistantConical Structures Based on Direct Measurements 被引量:1
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作者 Ning Xu QianjinYue +2 位作者 Shuai Yuan Xueqin Liu Wenqi Shi 《Journal of Marine Science and Application》 CSCD 2016年第4期376-381,共6页
Ice-induced structural vibration generally decreases with an increase in structural width at the waterline. Definitions of wide/narrow ice-resistant conical structures, according to ice-induced vibration, are directly... Ice-induced structural vibration generally decreases with an increase in structural width at the waterline. Definitions of wide/narrow ice-resistant conical structures, according to ice-induced vibration, are directly related to structure width, sea ice parameters, and clearing modes of broken ice. This paper proposes three clearing modes for broken ice acting on conical structures: complete clearing, temporary ice pile up, and ice pile up. In this paper, sea ice clearing modes and the formation requirements of dynamic ice force are analyzed to explore criteria determining wide/narrow ice-resistant conical structures. According to the direct measurement data of typical prototype structures, quantitative criteria of the ratio of a cone width at waterline(D) to sea ice thickness(h) is proposed. If the ratio is less than 30(narrow conical structure), broken ice is completely cleared and a dynamic ice force is produced; however, if the ratio is larger than 50(wide conical structure), the front stacking of broken ice or dynamic ice force will not occur. 展开更多
关键词 narrow/wide structure broken ice clearing mode complete clearing complete unloading dynamic ice force conical structure classification criteria
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What do Hainan’s Island-Wide Special Customs Operations Mean for the World?
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作者 ZHANG JUAN 《China Today》 2026年第3期26-31,共6页
THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive int... THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive interview with Feng Fei,secretary of the Hainan Provincial Committee of the Communist Party of China(CPC)and chairman of the Standing Committee of the Hainan Provincial People’s Congress. 展开更多
关键词 Trade Liberalization Customs Efficiency Economic Development Free Trade Port Policy Hainan Free Trade Port Customs Reform free trade port ftp officially Island wide Special Customs Operations
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A seismic modeling analysis of wide and narrow 3D observation systems for channel sand bodies 被引量:4
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作者 狄帮让 徐秀仓 魏建新 《Applied Geophysics》 SCIE CSCD 2008年第4期294-300,共7页
The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utili... The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utilize 3D physical seismic modeling experiments. A 3D channel sand body physical seismic model is constructed and two acquisition systems are designed with wide azimuth (16 lines) and narrow azimuth (8 lines) to model 3D seismic data acquisition and processing seismic work flows. From analysis of migrated time slice data with high quality and small size, we conclude that when the overlying layers are smooth and lateral velocities have little change, both wide and narrow azimuth observation systems in 3D acquisition can be used for obtaining high precision imaging and equivalent resolution of the channel sand body. 展开更多
关键词 wide and narrow azimuth observation systems seismic imaging physicalseismic modeling time slice RESOLUTION
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Wide/narrow azimuth acquisition footprints and their effects on seismic imaging 被引量:3
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作者 Di Bangrang Xu Xiucang Wei Jianxin 《Petroleum Science》 SCIE CAS CSCD 2008年第4期308-313,共6页
Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering.At present,the study on acquisition footpr... Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering.At present,the study on acquisition footprints has become a hot spot.In partnership with the Dagang Oilfield,we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging.In addition,the footprints caused by data processing of the normal moveout offset(NMO)stretching aberration were discussed.These footprints are located only in the shallow or middle layer in the time slice,and possibly affect the imaging of shallow target layers,and have no influence on deep target imaging.Seismic physical modeling has its advantages in the study of acquisition footprints. 展开更多
关键词 wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging
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Nerve compression and pain in human volunteers with narrow vs wide tourniquets 被引量:1
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作者 Florian M Kovar Manuela Jaindl +5 位作者 Gerhard Oberleitner Georg Endler Julia Breitenseher Daniela Prayer Gregor Kasprian Florian Kutscha-Lissberg 《World Journal of Orthopedics》 2015年第4期394-399,共6页
AIM: To assess the clinical effects and the morphological grade of nerve compression.METHODS: In a prospective single-center randomized, open study we assessed the clinical effects and the morphological grade of nerve... AIM: To assess the clinical effects and the morphological grade of nerve compression.METHODS: In a prospective single-center randomized, open study we assessed the clinical effects and the morphological grade of nerve compression during 20 min of either a silicon ring(group A) or pneumatic tourniquet(group B) placement variantly on the upper non-dominant limb in 14 healthy human volunteers. Before and during compression, the median and radial nerves were visualized in both groups by 3 Tesla MR imaging, using high resolutional(2.5 mm slice thickness) axial T2-weighted sequences. RESULTS: In group A, Visual analog pain scale was 5.4 ± 2.2 compared to results of group B, 2.9 ± 2.5, showing a significant difference(P = 0.028). FPS levels in group A were 2.6 ± 0.9 compared to levels in group B 1.6 ± 1, showing a significant difference(P = 0.039). Results related to measureable effect on median and radial nerve function were equal in both groups. No undue pressure signs on the skin, redness or nerve damage occurred in either group. There was no significant difference in the diameters of the nerves without and under compression in either group on T2 weighted images.CONCLUSION: Based on our results, no differences between narrow and wide tourniquets were identified. Silicon ring tourniquets can be regarded as safe for short time application. 展开更多
关键词 NERVE compression Magnetic resnane iamge wide TOURNIQUET narrow TOURNIQUET Human VOLUNTEERS
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Narrow-band high-transmittance birefringent filter and its application in wide color gamut display 被引量:2
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作者 Chi Zhang Rui Niu +3 位作者 Wenjuan Li Xiaoshuai Li Hongmei Ma Yubao Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期401-405,共5页
We propose a narrow-band birefringent filter and its application in wide color gamut.The birefringent filter consists of five phase retarders and two polarizers,and it has both narrow band and high transmittance.In th... We propose a narrow-band birefringent filter and its application in wide color gamut.The birefringent filter consists of five phase retarders and two polarizers,and it has both narrow band and high transmittance.In the experiment,we fabricate the birefringent filter using quartz phase retarders and polarizers,and apply it in serval different displays.The color gamuts of displays are enhanced more than 30%NTSC(National Television System Committee),and the widest color gamuts that have been obtained are 126%NTSC in liquid crystal displays and 138%NTSC in organic light-emitting devices.Moreover,the deep blue light in spectrum of display can be reduced using the birefringent filter.The birefringent filter can be an efficient element to achieve wide color gamut display. 展开更多
关键词 narrow band filter wide color gamut DISPLAY
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Widely tunable/wavelength-swept SLM fiber laser with ultra-narrow linewidth and ultra-high OSNR 被引量:3
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作者 冯亭 丁东亮 +2 位作者 刘鹏 苏红新 YAO X.Steve 《Optoelectronics Letters》 EI 2016年第6期433-436,共4页
We propose and demonstrate a novel single-longitudinal-mode(SLM) erbium-doped fiber laser(EDFL) capable of operating at fixed-wavelength lasing mode with a tunable range more than 54 nm, an ultra-narrow linewidth of 4... We propose and demonstrate a novel single-longitudinal-mode(SLM) erbium-doped fiber laser(EDFL) capable of operating at fixed-wavelength lasing mode with a tunable range more than 54 nm, an ultra-narrow linewidth of 473 Hz and an ultra-high optical signal-to-noise ratio(OSNR) more than 72 dB, or operating at wavelength-swept mode with tunable sweep rate of 10—200 Hz and a sweep range more than 50 nm. The excellent features mainly benefit from a triple-ring subring cavity constructed by three optical couplers nested one another and a fiber Fabry-Pérot tunable filter which can be driven by a constant voltage or a periodic sweep voltage for fixed or wavelength-swept operation, respectively. The proposed EDFL has potential applications in high-resolution spectroscopy and fiber optic sensing. 展开更多
关键词 tunable OSNR narrow lasing longitudinal triple capable Fabry sweep coupler
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Application of Alternate Planting Technology in Wide and Narrow Rows of Maize
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作者 WANG Fei 《外文科技期刊数据库(文摘版)自然科学》 2021年第7期032-034,共5页
China is one of the world's largest agricultural countries, planting a variety of crops, and maize is one of which has a relatively large planting area and is an important food and commercial crop. With the develo... China is one of the world's largest agricultural countries, planting a variety of crops, and maize is one of which has a relatively large planting area and is an important food and commercial crop. With the development of agricultural modernization, the high-yield planting technology of maize has been in continuous research and development, among which many advanced technologies have been applied. Wide-narrow row alternate planting is one of the more representative ones, and its application scope is very wide. Almost all planting areas of maize are adopting it, which has made an important contribution to the improvement of high-yield and quality of maize. In this paper, the application of maize's wide and narrow row alternate planting technology is analyzed in depth. 展开更多
关键词 MAIZE wide and narrow rows alternate planting technique
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Structural design in re duce d graphene oxide(RGO)metacomposites for enhanced microwave absorption in wide temperature spectrum 被引量:4
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作者 Haoxu Si Yi Zhang +5 位作者 Yuhao Liu Zhiyang Jiang Cuiping Li Jingwei Zhang Xiaoxiao Huang Chunhong Gong 《Journal of Materials Science & Technology》 2025年第3期211-220,共10页
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa... High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum. 展开更多
关键词 Microwave absorbing materials Metacomposites Equivalent electromagnetic parameters Structural parameters wide temperature spectrum
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Seeking new,ultra-narrow-band blue emitting phosphors with high color purity for wide color gamut displays
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作者 Zuobin Tang Feng Du +3 位作者 Zhihua Leng Huidong Xie Yanyan Li Lei Zhao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第12期1876-1882,I0002,共8页
Ultra-narrow-band phosphors have gained widespread applications in lighting and displays to enhance brightness and improve color saturation.Typical phosphor designs employ UCr_(4)C_(4)-type compounds and designing new... Ultra-narrow-band phosphors have gained widespread applications in lighting and displays to enhance brightness and improve color saturation.Typical phosphor designs employ UCr_(4)C_(4)-type compounds and designing new narrow-band phosphors with high color purity is a major challenge.Here,we explored a Eu^(2+)-doped Ba_(5)GeO_(4)Br_(6)phosphor,showing a narrow-band blue emission(λ_(em)=436 nm) excitation at the near-ultraviolet light with a full width at half maximum of 30.7 nm and high color purity of 96.6%.In addition,attractive cathodoluminescence characteristics were systematically analyzed by varying filament current(30-70 mA) and accelerating voltage(3-7 eV).Robust anti-degradation behavior and color point stability under continuous electron beam bombardment were confirmed.Given its excellent performance in photoluminescence and cathodoluminescence,application in wide color gamut displays appears promising.Using commercial phosphors β-SiAlON:Eu^(2+)and K_(2)SiF6:Mn^(4+)as green and red light co nverte rs respectively,and the title phosphor as the blue light converters,the fabricated w-LED exhibits a wide color gamut of 82% NTSC. 展开更多
关键词 Blue-emitting phosphor BasGeO_(4)Br_(6):Eu^(2+) narrow band Phosphor-converted light-emitting diodes Field emission displays Rare earths
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宽窄行与增密对绿洲灌区玉米光合特性及资源利用的协同效应 被引量:1
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作者 陈桂平 韦金贵 +5 位作者 郭瑶 李盼 王菲儿 仇海龙 冯福学 殷文 《中国农业科学》 北大核心 2026年第2期278-291,共14页
【目的】针对西北绿洲灌区等行距种植玉米增产潜力有限、资源利用效率不高和经济效益提升困难等普遍性科学问题,探讨宽窄行种植模式对玉米耐密性提升及其增产潜力的影响。【方法】试验开始于2017年,于2019―2021年进行数据采集,采用裂... 【目的】针对西北绿洲灌区等行距种植玉米增产潜力有限、资源利用效率不高和经济效益提升困难等普遍性科学问题,探讨宽窄行种植模式对玉米耐密性提升及其增产潜力的影响。【方法】试验开始于2017年,于2019―2021年进行数据采集,采用裂区设计。主区设3个宽窄行行距水平,宽窄行比例为7:3(L1,宽行56 cm:窄行24 cm)、6:4(L2,宽行48 cm:窄行32 cm)和5:5(L3,宽行40 cm:窄行40 cm);裂区对应4个玉米种植密度,分别为8.25万株/hm^(2)(D1,当地传统种植密度)、9.00万株/hm^(2)(D2,增密9.1%)、9.75万株/hm^(2)(D3,增密18.2%)和10.50万株/hm^(2)(D4,增密27.3%),探讨不同行距种植结合增密对玉米光合特性、产量、资源利用效率、土壤氮素含量和经济效益的影响。【结果】河西绿洲灌区玉米宽窄行种植和增密均提升了玉米光合特征、产量和资源利用效率。与等行距相比,宽窄行比例为7:3的处理分别平均提高玉米叶面积指数、大喇叭口期光截获分数、籽粒产量、光能利用效率、水分利用效率和氮素利用效率9.7%、7.1%、8.8%、8.2%、12.7%和14.1%;增密9.1%和增密18.2%的处理较当地传统种植密度的叶面积指数、大喇叭口期光截获分数、籽粒产量、光能利用效率、水分利用效率分别提高平均11.4%和15.7%、7.4%和10.1%、9.6%和11.3%、4.0%和6.1%、10.2%和20.5%。宽窄行比例为7:3结合增密18.2%对玉米的综合效应提升潜力大,较等行距当地传统种植密度分别提高玉米平均叶面积指数28.4%,提升大喇叭口期和灌浆期光截获分数22.0%和17.1%;分别增加玉米籽粒产量、生物量和收获指数22.2%、13.1%和8.0%;分别提高光能、水分和氮素利用效率13.5%、39.6%和24.0%;分别降低土壤全氮、铵态氮和硝态氮含量11.2%、18.0%和16.8%。此外,与等行距传统种植密度相比,宽窄行比例为7:3结合增密18.2%的处理提高了玉米净收益和产投比50.1%和23.3%。【结论】宽窄行比例为7:3的种植模式通过改善光合特征、产量、资源利用效率及土壤氮素供给,进而增强了玉米耐密性,实现玉米综合效应提升。 展开更多
关键词 宽窄行种植 种植密度 玉米增产 资源利用效率 光合特征 土壤氮素供给
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A 112 Gbps DSP-based PAM4 SerDes receiver with a wide band equalization tuning AFE in 7 nm FinFET 被引量:1
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作者 Huanan Guo Yufeng Yao +1 位作者 Jiazhen Ni Xiang Gao 《Journal of Semiconductors》 2025年第6期44-52,共9页
In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitte... In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitter configurations,this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE.The AFE is realized by implementing source degeneration transconductance,feedforward high-pass branch and inductive feedback peaking TIA.The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain.With the pro-posed AFE,the receiver demonstrates eye opening after digital FIR equalization and achieves 6×10^(-9) BER with a 29.6 dB inser-tion loss channel. 展开更多
关键词 AFE 112Gbps SerDes receiver wide band equalization
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Passive earth pressure of narrow backfill considering seismic-unsaturated seepage multi-field coupling effect 被引量:1
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作者 WANG Ze-yue LIN Hang 《Journal of Central South University》 2025年第4期1447-1467,共21页
Narrow backfill earth pressure estimation is applied to study the stability of supporting structures in the vicinity of existing buildings.Previous narrow backfill earth pressure studies have neglected seismic-unsatur... Narrow backfill earth pressure estimation is applied to study the stability of supporting structures in the vicinity of existing buildings.Previous narrow backfill earth pressure studies have neglected seismic-unsaturated seepage multi-field coupling,resulting in inaccurate estimates.To address these deficiencies,this paper proposed a calculation method for seismic passive earth pressure in unsaturated narrow backfill,based on inclined thin-layer units.It considers the interlayer shear stress,arching effect,and the multi-field coupling of seismic-unsaturated seepage.Additionally,this paper includes a parametric sensitivity analysis.The outcomes indicate that the earthquake passive ground pressure of unsaturated narrow backfill can be reduced by increasing the aspect ratio,seismic acceleration coefficient,and unsaturation parameterα.It can also be reduced by decreasing the effective interior friction angle,soil cohesion,wallearth friction angle,and vertical discharge.Furthermore,for any width soil,lowering the elevation of the action point of passive thrust can be attained by raising the effective interior friction angle,wall-earth friction angle,and unsaturation parameterα.Reducing soil cohesion,seismic acceleration coefficient,and vertical discharge can also lower the height of the application point of passive thrust. 展开更多
关键词 passive earth pressure unsaturated steady seepage arching effect narrow backfill EARTHQUAKE
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A survey on Ultra Wide Band based localization for mobile autonomous machines 被引量:1
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作者 Ning Xu Mingyang Guan Changyun Wen 《Journal of Automation and Intelligence》 2025年第2期82-97,共16页
The fast growth of mobile autonomous machines from traditional equipment to unmanned autonomous vehicles has fueled the demand for accurate and reliable localization solutions in diverse application domains.Ultra Wide... The fast growth of mobile autonomous machines from traditional equipment to unmanned autonomous vehicles has fueled the demand for accurate and reliable localization solutions in diverse application domains.Ultra Wide Band(UWB)technology has emerged as a promising candidate for addressing this need,offering high precision,immunity to multipath interference,and robust performance in challenging environments.In this comprehensive survey,we systematically explore UWB-based localization for mobile autonomous machines,spanning from fundamental principles to future trends.To the best of our knowledge,this review paper stands as the pioneer in systematically dissecting the algorithms of UWB-based localization for mobile autonomous machines,covering a spectrum from bottom-ranging schemes to advanced sensor fusion,error mitigation,and optimization techniques.By synthesizing existing knowledge,evaluating current methodologies,and highlighting future trends,this review aims to catalyze progress and innovation in the field,unlocking new opportunities for mobile autonomous machine applications across diverse industries and domains.Thus,it serves as a valuable resource for researchers,practitioners,and stakeholders interested in advancing the state-of-the-art UWB-based localization for mobile autonomous machines. 展开更多
关键词 Ultra wide Band LOCALIZATION Mobile autonomous machines Error mitigation Optimization Sensor fusion
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Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range
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作者 Tingsong Hu Wenyi Lian +4 位作者 Kang Hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期160-175,共16页
Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kine... Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kinetics.Herein,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as cathode.The unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon illumination.The illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 cycles.Even at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT cathode.This work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency. 展开更多
关键词 Li-CO_(2)batteries Photo-energized wide operation-temperature Kinetics MoS_(2)
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Wide & Narrow:多学科设计工作室
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《包装与设计》 2017年第5期40-47,共8页
位于泰国曼谷的Wide&Narrow是一家专注于视觉概念和艺术指导的多学科设计工作室,于2013年由设计师Kanwee Harichanwong和Poomruethai Suebsantiwongse创立,其服务囊括了品牌设计的方方面面,从品牌策略咨询,到标识设计、命名、包装... 位于泰国曼谷的Wide&Narrow是一家专注于视觉概念和艺术指导的多学科设计工作室,于2013年由设计师Kanwee Harichanwong和Poomruethai Suebsantiwongse创立,其服务囊括了品牌设计的方方面面,从品牌策略咨询,到标识设计、命名、包装设计、插画设计,再到室内设计、用户界面设计、电子商务网页设计等等。 展开更多
关键词 设计工作室 wide 多学科 用户界面设计 品牌设计 品牌策略 标识设计 包装设计
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2CML-2型大垄宽窄双行木薯种植机设计与试验
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作者 崔振德 邓干然 +3 位作者 黄洁 杨望 廖宇兰 周思理 《中国农机化学报》 北大核心 2026年第4期1-6,46,共7页
为实现木薯大垄双行机械化种植模式,设计一种开沟、施肥、切种、排种、覆土一体化作业的垄作式宽窄双行木薯种植机。对样机关键部件进行设计,确定其施肥装置、对辊式切种机构、滑槽式排种系统工作参数,同时分析木薯切种排种装置作业过程... 为实现木薯大垄双行机械化种植模式,设计一种开沟、施肥、切种、排种、覆土一体化作业的垄作式宽窄双行木薯种植机。对样机关键部件进行设计,确定其施肥装置、对辊式切种机构、滑槽式排种系统工作参数,同时分析木薯切种排种装置作业过程,得到满足木薯种茎覆土厚度的必要作业条件。田间试验结果表明,当作业速度为0.5~0.9 m/s时,种段合格率≥98.3%、漏播率≤0.4%、露种率为0%、肥料覆盖率为100%、施肥量偏差为3.2%、种植深度合格率为97.6%、生产率为0.4~0.56 hm^(2)/h,试验指标均符合行业标准要求,试验结果满足设计和实际作业要求。 展开更多
关键词 木薯种植机 大垄宽窄行 施肥装置 排种装置 切种机构 整秆式
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垄作双行直落式菠萝移栽机设计与试验
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作者 崔振德 颜彬 +3 位作者 李玲 邓干然 陈品岚 刘泽华 《中国农机化学报》 北大核心 2026年第3期1-7,共7页
针对菠萝种苗苗体大、叶片多、种植密度大导致的菠萝机械化栽植故障率高、效率低等问题,基于菠萝种苗的物理特性和移栽作业工艺要求,设计一种直落式菠萝移栽机,可满足垄上菠萝种苗直落栽植作业。根据直落栽植作业流程,采用模块化设计方... 针对菠萝种苗苗体大、叶片多、种植密度大导致的菠萝机械化栽植故障率高、效率低等问题,基于菠萝种苗的物理特性和移栽作业工艺要求,设计一种直落式菠萝移栽机,可满足垄上菠萝种苗直落栽植作业。根据直落栽植作业流程,采用模块化设计方法,设计移栽机整体结构,主要包括投苗装置、开沟装置、覆土装置等部分,实现破土开沟—种苗投放—均匀分苗—稳定立苗—覆土压实一体化作业流程。同时,采用理论计算与虚拟设计相结合的方法,明确各关键部件的尺寸参数。最后,对直落式菠萝移栽机进行物理样机加工及田间试验验证。田间试验结果表明,当作业速度为0.25~0.35 m/s时,栽植合格率≥91.16%、漏植率≤1.1%、株距合格率≥95.03%、栽植深度合格率为93.37%、纯工作小时生产率为0.17 hm^(2)/h,试验指标均满足设计要求。可为同类型其他作物直落式移栽机的设计提供参考。 展开更多
关键词 菠萝 一垄双行 移栽机 宽窄行种植 直落式
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Endovascular electrocoagulation for treating a blister-like microaneurysm with an extremely narrow neck:A case report
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作者 Zhi-Yuan Zhang Xian-Yi Zhang +3 位作者 Guo-Zhang Lu Shi-Lei Wang Ji-Heng Hao Li-Yong Zhang 《World Journal of Clinical Cases》 2025年第32期110-115,共6页
BACKGROUND Intracranial blister-like microaneurysms are an extremely rare disease.Rupture of intracranial aneurysms can lead to subarachnoid hemorrhage(SAH).Patients with SAH may experience severe neurological symptom... BACKGROUND Intracranial blister-like microaneurysms are an extremely rare disease.Rupture of intracranial aneurysms can lead to subarachnoid hemorrhage(SAH).Patients with SAH may experience severe neurological symptoms,including severe headache,nausea,vomiting,transient or persistent loss of consciousness,limb weakness,and blurred vision.Ruptured aneurysms should be surgically treated as soon as possible.Intravascular electrocoagulation is becoming a promising treatment method for intracranial blister-like microaneurysms.The short-term follow-up results demonstrated that this method is safe and effective.This article presents a case of endovascular electrocoagulation for the treatment of a blisterlike microaneurysm.CASE SUMMARY This article reports the case of 71-year-old female patient with an intracranial aneurysm.The patient experienced a sudden headache with vomiting for 3 hours.Brain computed tomography(CT)scan showed a subarachnoid hemorrhage.She was diagnosed with rupture of an aneurysm and subarachnoid hemorrhage.The aneurysm was located in the choroidal segment of the right internal carotid artery.The size of the aneurysm was 2.00 mm×1.80 mm×1.97 mm,and the neck of the aneurysm was less than 0.5 mm wide.We successfully treated this aneurysm with endovascular electrocoagulation,and the patient was safely returned to the ward and discharged after subsequent supportive treatment.CT angiography reexamination 3 months after surgery revealed no contrast agent extravasation in the original lesion,with a good prognosis.CONCLUSION Endovascular electrocoagulation is an effective and safe method for the treatment of intracranial blister-like microaneurysms. 展开更多
关键词 MICROANEURYSM Blister-like Endovascular electrocoagulation Extremely narrow neck Case report
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