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Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma
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作者 Hai-Jian Hu Ping Li +7 位作者 Bin Tong Yu-Lian Pang Hong-Dou Luo Fei-Fei Wang Chan Xiong Yu-Lin Yu Hai He Xu Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期852-860,共9页
AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma.METHODS:T... AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma.METHODS:Totally 127 eyes from 89 participants(36 eyes of 19 healthy participants,45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients)were included.The relationships between the optical coherence tomography(OCT)-derived parameters and VF sensitivity were determined.Patients with early glaucoma were divided into eyes with or without central 10°of the VF damages(CVFDs),and the diagnostic performances of OCT-derived parameters were assessed.RESULTS:In early glaucoma,the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation(PSD;with average mGCIPLT:β=-0.046,95%CI,-0.067 to-0.024,P<0.001).In advanced glaucoma,the mGCIPLT was related to the 24-2 VF mean deviation(MD;with average mGCIPLT:β=0.397,95%CI,0.199 to 0.595,P<0.001),10-2 VF MD(with average mGCIPLT:β=0.762,95%CI,0.485 to 1.038,P<0.001)and 24-2 VF PSD(with average mGCIPLT:β=0.244,95%CI,0.124 to 0.364,P<0.001).Except for the minimum and superotemporal mGCIPLT,the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs.The area under the curve(AUC)of the average mGCIPLT(AUC=0.949,95%CI,0.868 to 0.982)was greater than that of the average circumpapillary retinal nerve fiber layer thickness(cpRNFLT;AUC=0.827,95%CI,0.674 to 0.918)and rim area(AUC=0.799,95%CI,0.610 to 0.907)in early glaucomatous eyes with CVFDs versus normal eyes.CONCLUSION:The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF,cpRNFLT and ONH parameters,especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level. 展开更多
关键词 10-2 visual field ganglion cell-inner plexiform layer retinal nerve fiber layer thickness GLAUCOMA
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Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping 被引量:1
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作者 Yongchao Yao Shengjun Sun +14 位作者 Hui Zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang Bo Tang Xuping Sun Wenchuang(Walter)Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期306-312,共7页
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau... Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution. 展开更多
关键词 Ce doping NiFe layered double hydroxide Seawater oxidation Electrocatalysis Cl^(-) repulsion
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Characterization of Cd1-xZnxTe(0≤x≤1) Nanolayers Grown by Atomic Layer Deposition on GaSb and GaAs(001) Oriented Substrates
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作者 Joel Díaz-Reyes Roberto Saúl Castillo-Ojeda José Eladio Flores-Mena 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第2期97-108,共12页
ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these material... ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (ALD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of Raman spectroscopy measurements. Raman scattering shows the peak corresponding to longitudinal optical (LO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, Raman spectra presented the LO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature. 展开更多
关键词 - SUBSTRATES atomic layer deposition(ALD) defect generation mechanism TERNARY alloy Cd1-xZnxTe Zn and Cd mixture
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Penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers
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作者 Yan-Song Li Zeng-He Xu Wen-Jie Feng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期371-381,共11页
A penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers subjected to magnetoelectromechanical loads is investigated,where the magnetoelectrically impermeable crack surface condition is adopted... A penny-shaped interfacial crack between dissimilar magnetoelectroelastic layers subjected to magnetoelectromechanical loads is investigated,where the magnetoelectrically impermeable crack surface condition is adopted. By using Hankel transform technique,the mixed boundary value problem is firstly reduced to a system of singular integral equations,which are further reduced to a system of algebraic equations. The field intensity factors and energy release rate are finally derived. Numerical results elucidate the eects of crack configuration,electric and/or magnetic loads,and material parameters of the magnetoelectroelastic layers on crack propagation and growth. This work should be useful for the design of magnetoelectroelastic composite structures. 展开更多
关键词 Interfacial crack . Penny-shaped crack - Hankel transform . Energy release rate.Magnetoelectroelastic layer
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Reflection of Liberal Values in the Georgian Press in 1918-1921
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作者 Manana Shamilishvili Mari Tsereteli 《International Relations and Diplomacy》 2016年第5期341-352,共12页
This study deals with the values and orientation of Georgian social and political publications in the times of the Georgian Democratic Republic (1918-1921). It also shows how the press of that time reflected the ide... This study deals with the values and orientation of Georgian social and political publications in the times of the Georgian Democratic Republic (1918-1921). It also shows how the press of that time reflected the idea of "Georgian Europeanism" based on liberal values that took shape as an anti-colonial concept in the journalism of the late 19th century. The opposed dominant ideological projects of that era comprised on the one hand, National Democratic and Socialist Federalist parties that aspired to preserve national identity and carry out changes and on the other hand, ruling Social Democrats (who initially neglected national identity, but later shared the idea). This opposition was clearly reflected in the media discourse of that time, which implied the following rights based on the principles of classical liberalism: freedom of conscience and expression, rule of law, personal independence, and individual rights. Other elements were added to this list later. The issue of religious tolerance also became topical. Journalist texts of the period reflected and rationalised the values recognised in today's democratic and liberal communities. The research was carried out in the archives of the periodicals of the aforementioned period (newspapers Sakhalkho Sakme, Sakartvelo, Ertoba, and Sakartvelos Respublika) by means of systematising and classifying retrieved materials and making a substantive and varietal analysis of individual media texts. 展开更多
关键词 Georgian journalism the Georgian Party Press in 1918-1921 the liberal values the idea of Georgian Europeanism
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Electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel with copper interlayer sheet 被引量:9
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作者 王廷 张秉刚 +2 位作者 陈国庆 冯吉才 唐奇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1829-1834,共6页
Electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel with a copper sheet as interlayer was carried out.Microstructures of the joint were studied by optical microscopy(OM),scanning electron microscopy... Electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel with a copper sheet as interlayer was carried out.Microstructures of the joint were studied by optical microscopy(OM),scanning electron microscopy(SEM) and X-ray diffractometry(XRD).In addition,the mechanical properties of the joint were evaluated by tensile test and the microhardness was measured.These two alloys were successfully welded by adding copper transition layer into the weld.Solid solution with a certain thickness was located at the interfaces between weld and base metal in both sides.Regions inside the weld and near the stainless steel were characterized by solid solution of copper with TiFe2 intermetallics dispersedly distributed in it.While weld near titanium alloy contained Ti-Cu and Ti-Fe-Cu intermetallics layer,in which the hardness of weld came to the highest value.Brittle fracture occurred in the intermetallics layer when the joint was stretched. 展开更多
关键词 Ti-15-3 titanium alloy 304 stainless steel electron beam welding interrnetallics layer mechanical properties
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Effect of nitrite intercalated Mg-Al layered double hydroxides on mortar durability under Cl−and SO_(4)^(2-) coexisting environment 被引量:3
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作者 WANG Xu-hui XU Jin-xia TAN Qi-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期546-560,共15页
The aim of this paper is to investigate the effect of nitrite intercalated Mg-Al layered double hydroxides(Mg-Al LDH-NO_(2))on mortar durability under the coexisting environment of Cl−and SO_(4)^(2-).Cl−and SO_(4)^(2-... The aim of this paper is to investigate the effect of nitrite intercalated Mg-Al layered double hydroxides(Mg-Al LDH-NO_(2))on mortar durability under the coexisting environment of Cl−and SO_(4)^(2-).Cl−and SO_(4)^(2-) binding properties of Mg-Al LDH-NO_(2) in simulated concrete pore solutions,Cl−and SO_(4)^(2-) diffusion properties of mortars with Mg-Al LDHNO 2 were examined.The steel corrosion and resistance of mortar against SO_(4)^(2-) attack were also evaluated.The results indicate that Mg-Al LDH-NO_(2) can effectively adsorb the Cl−and SO_(4)^(2-) in simulated concrete pore solution,and inhibit the diffusion of Cl−and SO_(4)^(2-) into cement mortars.The presence of SO_(4)^(2-) can greatly affect the uptake amount of Cl−,and there is a coupled effect of Cl−and SO_(4)^(2-) on their penetration into mortar specimens.In addition,Mg-Al LDH-NO_(2) can greatly upgrade the resistance of mortars against SO_(4)^(2-) attack and well prevent the steel from corrosion.However,Cl−will aggravate the SO_(4)^(2-) attack and SO_(4)^(2-) can initially decrease and then increase the steel corrosion. 展开更多
关键词 layered double hydroxides mortar durability SO_(4)^(2-)attack steel corrosion Cl−and SO_(4)^(2-)coexisting environment
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 Water-flooded reservoirs layer regrouping.Flow resistance - High water cut Reservoir simulation
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Evaluation of Microstructure and Wear Properties of Ti-6Al-4V Alloy Plasma Carbonized at Different Temperatures 被引量:1
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作者 张勇 WEI Qiulan +3 位作者 邢亚哲 JIANG Chaoping LI Xinghang ZHAO Zhiyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第3期631-638,共8页
Ti-6A1-4V (TC4) alloys were plasma carbonized at different temperatures (900, 950, and 1 000 ℃) for duration of 3 h. Graphite rod was employed as carbon supplier to avoid the hydrogen brittleness which is ubiquit... Ti-6A1-4V (TC4) alloys were plasma carbonized at different temperatures (900, 950, and 1 000 ℃) for duration of 3 h. Graphite rod was employed as carbon supplier to avoid the hydrogen brittleness which is ubiquitous in traditional gas carbonizing process. Two distinguished structures including a thin compound layer (carbides layer) and a thick layer with the mixed microstructure of TiC and the a-Ti in carburing layer were formed during carburizing. Furthermore, it was found that the microstructure and the properties of TC4 alloy were significantly related to the carbonizing temperature. The specimen plasma carbonized at 950 ~2 obtained maximum value both in the hardness and wear resistance. 展开更多
关键词 TI-6A1-4V plasma carburizing layer wear resistance
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Performance Analysis of Physical Layer Security over α-η-κ-μ Fading Channels 被引量:1
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作者 Shaobo Jia Jiayan Zhang +1 位作者 Honglin Zhao Yao Xu 《China Communications》 SCIE CSCD 2018年第11期138-148,共11页
In this paper, we consider the secure data transmission over α-η-κ-μ fading channels, which are recently proposed to encompass nearly all the well-known statistical models adopted in the literature. In particular,... In this paper, we consider the secure data transmission over α-η-κ-μ fading channels, which are recently proposed to encompass nearly all the well-known statistical models adopted in the literature. In particular, we address the secrecy performance in terms of the average secrecy capacity(ASC) and the secrecy outage probability(SOP), for which novel analytical expressions are derived. Simulation results verify the analysis and demonstrate the impact of the physical parameters on the secrecy performance of this new channel fading model. 展开更多
关键词 Physical layer security α-η-κ-μgeneralized fading channels average secrecycapacity secrecy outage probability
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Non-use value assessment for wetland ecosystem service of Hongxing National Nature Reserve in northeast China 被引量:1
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作者 Xin Jin Jianzhang Ma +1 位作者 Tijiu Cai Xiaoxin Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第6期1435-1442,共8页
By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing... By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing to pay (WTP) for protection of HNNR was 63 %. The WTP ratio was affected by geographical area, contact nature, personal preferences, and familiar degree of the respondents. The WTP value was affected by age, education level and career of the respondents. The mainly reasons for people rejecting to pay for protecting HNNR were "I am not familiar to HNNR" and "I had no capacity for additional spending because of low income". Weighted average individual WTP value was CNY 59.26 Yuan ind.^-1 year^-1 for all the respondents with WTP. The total non-use ecosystem service value of HNNR was CNY 1430 million Yuan in 2013. The heritage value was highest followed by existence value and option value. From the high ecosystem service value in HNNR, it is very important to construct nature reserve for protecting natural ecosystems and human sustainable use of natural resources. 展开更多
关键词 Ecosystem service Non-use value Hongxing National Nature Reserve - Xiaoxing'an Mountains
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Desorption of Cl^(-) from Mg-Al layered double hydroxide intercalated with Cl^(-) using CO_(2) gas and water 被引量:1
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作者 Tomohito Kameda Hiroki Uchida +5 位作者 Shogo Kumagai Yuko Saito Keiichi Mizushina Ichirou Itou Tianye Han Toshiaki Yoshioka 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期131-134,共4页
Mg-Al layered double hydroxide intercalated with CO_(3)^(2-)(CO_(3)·Mg-Al LDH) is effective for treating HCl exhaust gas.HCl reacts with CO_(3)^(2-) in CO_(3)·Mg-Al LDH, resulting in the formation of Cl·... Mg-Al layered double hydroxide intercalated with CO_(3)^(2-)(CO_(3)·Mg-Al LDH) is effective for treating HCl exhaust gas.HCl reacts with CO_(3)^(2-) in CO_(3)·Mg-Al LDH, resulting in the formation of Cl·Mg-Al LDH.We propose that CO_(2) can be used for the desorption of Cl^(-)from Cl·Mg-Al LDH to regenerate CO_(3)·Mg-Al LDH.Herein,we studied the desorption of a from CI-Mg-Al LDH by adding water to Cl·Mg-Al LDH and blowing CO_(2) into it.We also analyzed the effects of temperature and water addition speed on the desorption of CI^(-)from Cl·Mg-Al LDH.Our results show that the added water adhered to CI·Mg-Al LDH and that CO_(2) in the gaseous phase was dissolved in this adhered water,thus generating CO_(3)^(2-).Therefore,anion exchange occurred between CO_(3)^(2-) and Cl^(-)in the Cl·Mg-Al LDH,thus desorbing Cl^(-). 展开更多
关键词 Mg-Al layered double hydroxide CO_(2)gas Cl^(-)desorption Semi-dry method
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Promoting surface reconstruction of NiFe layered double hydroxides via intercalating[Cr(C_(2)O_(4))_(3)]^(3-)for enhanced oxygen evolution 被引量:2
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作者 Yujie Wu Minglei Song +8 位作者 Yu-Cheng Huang Chung-Li Dong Yingying Li Yuxuan Lu Bo Zhou Dongdong Wang Jianfeng Jia Shuangyin Wang Yanyong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期140-148,I0005,共10页
Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(... Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis. 展开更多
关键词 NiFe layered double hydroxides [Cr(C_(2)O_(4))_(3)]^(3-)intercalation Dynamic restructuring Operando spectroscopies Oxygen evolution reaction
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Dynamics of low-speed streak evolution and interaction in laminar boundary layer 被引量:1
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作者 Si-Chao Deng Chong Pan Jin-Jun Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期636-645,共10页
The present paper presents an experimental effort on the regeneration process of two low-speed laminar streaks in a zero-pressure-gradient laminar boundary layer. Two vertical thin wires separated by a spanwise distan... The present paper presents an experimental effort on the regeneration process of two low-speed laminar streaks in a zero-pressure-gradient laminar boundary layer. Two vertical thin wires separated by a spanwise distance of 30 mm are used to introduce disturbances of two rolls of transitional Karmain vortex street to the downstream boundary layer. Both hydrogen bubble visualization and particle image velocimetry (PIV) measurement show that two lowspeed streaks are induced through leading-edge receptivity process. As these streaks develop in the downstream, two additional low-speed streaks begin to appear outboard of the flank of the original two, together with complex dynamics of streak splitting and merging. A flow pattern of four streaks aligned along the spanwise direction occurs finally in the far downstream. It is found that besides the mechanisms of streak breakdown, the streak interaction is also an important factor characterizing the instability of low speed streaks and their regeneration process. 展开更多
关键词 Low-speed streak - Boundary layer transition Streak reproduction
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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture Comparative Analysis PROOF Natural Numbers Integer Sequences Factorial Processes Par-tial Differential Equations Bounded values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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A Compact Difference Scheme for Multi-point Boundary Value Problems of Heat Equations
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作者 Xuping Wang Zhizhong Sun 《Communications on Applied Mathematics and Computation》 2019年第4期545-563,共19页
In this paper,a compact difference scheme is established for the heat equations with multi-point boundary value conditions.The truncation error of the difference scheme is O(τ2+h^4),where t and h are the temporal ste... In this paper,a compact difference scheme is established for the heat equations with multi-point boundary value conditions.The truncation error of the difference scheme is O(τ2+h^4),where t and h are the temporal step size and the spatial step size.A prior estimate of the difference solution in a weighted norm is obtained.The unique solvability,stability and convergence of the difference scheme are proved by the energy method.The theoretical statements for the solution of the difference scheme are supported by numerical examples. 展开更多
关键词 Heat EQUATION - Multi-point BOUNDARY valuE CONDITION COMPACT DIFFERENCE scheme Energy method
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Jacobi-Sobolev Orthogonal Polynomialsand Spectral Methods for Elliptic Boundary Value Problems
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作者 Xuhong Yu Zhongqing Wang Huiyuan Li 《Communications on Applied Mathematics and Computation》 2019年第2期283-308,共26页
Generalized Jacobi polynomials with indexes α,β∈ R are introduced and some basic properties are established. As examples of applications,the second- and fourth-order elliptic boundary value problems with Dirichlet ... Generalized Jacobi polynomials with indexes α,β∈ R are introduced and some basic properties are established. As examples of applications,the second- and fourth-order elliptic boundary value problems with Dirichlet or Robin boundary conditions are considered,and the generalized Jacobi spectral schemes are proposed. For the diagonalization of discrete systems,the Jacobi-Sobolev orthogonal basis functions are constructed,which allow the exact solutions and the approximate solutions to be represented in the forms of infinite and truncated Jacobi series. Error estimates are obtained and numerical results are provided to illustrate the effectiveness and the spectral accuracy. 展开更多
关键词 Generalized JACOBI POLYNOMIALS Spectral method - Jacobi-Sobolev ORTHOGONAL BASIS functions ELLIPTIC boundary value problems Error analysis
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Nondoped-type White Organic Light-Emitting Diode Using Star-Shaped Hexafluorenylbenzene as an Energy Transfer Layer
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作者 Jun-sheng Yu Tao Ma +2 位作者 Shuang-ling Lou Ya-dong Jiang Qing Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第5期500-504,共5页
White organic light-emitting diodes (WOLEDs) with a structure of indium-tin-oxide (ITO)/N,N'-bis- (1-naphthyl)-N,N'-diphenyl- (1, 1'-biphenyl)-4,4'-diamine (NPB)/1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluor... White organic light-emitting diodes (WOLEDs) with a structure of indium-tin-oxide (ITO)/N,N'-bis- (1-naphthyl)-N,N'-diphenyl- (1, 1'-biphenyl)-4,4'-diamine (NPB)/1,2,3,4,5,6-hexakis(9,9-diethyl-9H-fluoren-2- yl)benzene (HKEthFLYPh)/5,6,11,12-tetraphenylnaphtacene (rubrene)/tris(8-hydroxyquinoline) aluminum (Alq3)/Mg:Ag were fabricated by vacuum deposition method, in which a novel star-shaped hexafluorenyl- benzene HKEthFLYPh was used as an energy transfer layer, and an ultrathin layer of rubrene was inserted between HKEthFLYPh and Alq3 layers as a yellow light-emitting layer instead of using a time-consuming doping process. A fairly pure WOLED with Commissions Internationale De L'Eclairage (CIE) coordinates of (0.32, 0.33) was obtained when the thickness of rubrene was 0.3 nm, and the spectrum was insensitive to the applied voltage. The device yielded a maximum luminance of 4816 cd/m2 at 18 V. 展开更多
关键词 White organic light-emitting diode diethyl-9H-fluoren-2-yl)benzene Energy transfer Star-shaped hexafluorenylbenzene 1 2 3 4 5 6-hexakis(9 9- Ultrathin layer
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Role of 18F-fluorodeoxyglucose positron emission tomography imaging in surgery for pancreatic cancer 被引量:16
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作者 Hisao Wakabayashi Yoshihiro Nishiyama +5 位作者 Tsuyoshi Otani Takanori Sano Shinichi Yachida Keiichi Okano Kunihiko Izuishi Yasuyuki Suzuki 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期64-69,共6页
AIM: To evaluate the role of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) in the surgical management of patients with pancreatic cancer, including the diagnosis, staging, and selection of pat... AIM: To evaluate the role of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) in the surgical management of patients with pancreatic cancer, including the diagnosis, staging, and selection of patients for the subsequent surgical treatment. METHODS: This study involved 53 patients with proven primary pancreatic cancer. The sensitivity of diagnosing the primary cancer was examined for FDG-PET CT, cytological examination of the bile or pancreatic juice, and the serum levels of carcinoembrionic antigens (CEA) and carbohydrate antigen 19-9 (CA29-9). Next, the accuracy of staging was compared between FDG-PET and CT. Finally, FDG-PET was analyzed semiquantitatively using the standard uptake value (SUV). The impact of the SUV on patient management was evaluated by examining the correlations between the SUV and the histological findings of cancer. RESULTS: The sensitivity of FDG-PET, CT, cytological examination of the bile or pancreatic juice, and the serum levels of CEA and CA19-9 were 92.5%, 88.7%, 46.4%, 37.7% and 69.8%, respectively. In staging, FDG-PET was superior to CT only in diagnosing distant disease (bone metastasis). For local staging, the sensitivity of CT was better than that of FDG-PEr. The SUV did not correlate with the pTNM stage, grades, invasions to the vessels and nerve, or with the size of the tumor. However, there was a statistically significant difference (4.6 ± 2.9 vs 7.8 ± 4.5, P = 0.024) in the SUV between patients with respectable and unresectable disease. CONCLUSION: FDG-PET is thus considered to be useful in the diagnosis of pancreatic cancer. However, regarding the staging of the disease, FDG-PET is not considered to be a sufficiently accurate diagnostic modality. Although the SUV does not correlate with the patho-histological prognostic factors, it may be useful in selecting patients who should undergo subsequent surgical treatment. 展开更多
关键词 Pancreatic cancer Fluorodeoxyglucose positron emission tomography Computed tomography Standard uptake value Carcinoembrionic antigens Carbohydrate antigen 19-9 Prognostic factor
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