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Spatial distribution patterns of anorectal atresia/stenosis in China:Use of two-dimensional graph-theoretical clustering
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作者 Ping Yuan Liang Qiao +8 位作者 Li Dai Yan-Ping Wang Guang-Xuan Zhou Ying Han Xiao-Xia Liu Xun Zhang Yi Cao Juan Liang Jun Zhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第22期2787-2793,共7页
AIM:To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.METHODS:Data were collected from the Chinese Birth Defects Monitoring Network(CBDMN),a hospital-based congenital malformation... AIM:To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.METHODS:Data were collected from the Chinese Birth Defects Monitoring Network(CBDMN),a hospital-based congenital malformations registry system.All fetuses more than 28 wk of gestation and neonates up to 7 d of age in hospitals within the monitoring sites of the CBDMN were monitored from 2001 to 2005.Two-dimensional graph-theoretical clustering was used to divide monitoring sites of the CBDMN into different clusters according to the average incidences of anorectal atresia/stenosis in the different monitoring sites.RESULTS:The overall average incidence of anorectal atresia/stenosis in China was 3.17 per 10000 from 2001 to 2005.The areas with the highest average incidences of anorectal atresia/stenosis were almost always focused in Eastern China.The monitoring sites were grouped into 6 clusters of areas.Cluster 1 comprised the monitoring sites in Heilongjiang Province,Jilin Province,and Liaoning Province;Cluster 2 was composed of those in Fujian Province,Guangdong Province,Hainan Province,Guangxi Zhuang Autonomous Region,south Hunan Province,and south Jiangxi Province;Cluster 3 consisted of those in Beijing Municipal City,Tianjin Municipal City,Hebei Province,Shandong Province,north Jiangsu Province,and north Anhui Province;Cluster 4 was made up of those in Zhejiang Province,Shanghai Municipal City,south Anhui Province,south Jiangsu Province,north Hunan Province,north Jiangxi Province,Hubei Province,Henan Province,Shanxi Province and Inner Mongolia Autonomous Region;Cluster 5 consisted of those in Ningxia Hui Autonomous Region,Gansu Province and Qinghai Province;and Cluster 6 included those in Shaanxi Province,Sichuan Province,Chongqing Municipal City,Yunnan Province,Guizhou Province,Xinjiang Uygur Autonomous Province and Tibet Autonomous Region.CONCLUSION:The fi ndings in this research allow the display of the spatial distribution patterns of anorectal atresia/stenosis in China.These will have important guiding significance for further analysis of relevant environmental factors regarding anorectal atresia/ stenosis and for achieving regional monitoring for anorectal atresia/stenosis. 展开更多
关键词 Spatial distribution Anorectal atresia/ stenosis two-dimensional graph-theoretical clustering Incidence Monitoring
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Two-dimensional graphitic carbon nitride for membrane separation 被引量:2
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作者 Tao Zheng Xiuyang Zou +3 位作者 Meisheng Li Shouyong Zhou Yijiang Zhao Zhaoxiang Zhong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期297-311,共15页
Recent years,membrane separation technology has attracted significant research attention because of the efficient and environmentally friendly operation.The selection of suitable materials to improve the membrane sele... Recent years,membrane separation technology has attracted significant research attention because of the efficient and environmentally friendly operation.The selection of suitable materials to improve the membrane selectivity,permeability and other properties has become a topic of vital research relevance.Two-dimensional(2D)materials,a novel family of multifunctional materials,are widely used in membrane separation due to their unique structure and properties.In this respect,as a novel 2D material,graphitic carbon nitride(g-C_(3)N_(4))have found specific attention in membrane separation.This study reviews the application of carbon nitride in gas separation membranes,pervaporation membranes,nanofiltration membranes,reverse osmosis membranes,ion exchange membranes and catalytic membranes,along with describing the separation mechanisms. 展开更多
关键词 two-dimensional(ZD) g-C_(3)N_(4) Membranes SEPARATION
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Highly stable two-dimensional graphene oxide:Electronic properties of its periodic structure and optical properties of its nanostructures 被引量:1
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作者 张琴 张红 程新路 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期533-539,共7页
According to first principle simulations, we theoretically predict a type of stable single-layer graphene oxide(C_2O).Using density functional theory(DFT), C_2O is found to be a direct gap semiconductor. In additi... According to first principle simulations, we theoretically predict a type of stable single-layer graphene oxide(C_2O).Using density functional theory(DFT), C_2O is found to be a direct gap semiconductor. In addition, we obtain the absorption spectra of the periodic structure of C_2O, which show optical anisotropy. To study the optical properties of C_2O nanostructures, time-dependent density functional theory(TDDFT) is used. The C_2O nanostructure has a strong absorption near 7 eV when the incident light polarizes along the armchair-edge. Besides, we find that the optical properties can be controlled by the edge configuration and the size of the C_2O nanostructure. With the elongation strain increasing, the range of light absorption becomes wider and there is a red shift of absorption spectrum. 展开更多
关键词 two-dimensional(2D) materials graphene oxide surface plasmons
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Two-Dimensional MXene-Based Advanced Sensors for Neuromorphic Computing Intelligent Application
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作者 Lin Lu Bo Sun +2 位作者 Zheng Wang Jialin Meng Tianyu Wang 《Nano-Micro Letters》 2026年第2期664-691,共28页
As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and el... As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies. 展开更多
关键词 two-dimensional MXenes SENSOR Neuromorphic computing Multimodal intelligent system Wearable electronics
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Emergent high-temperature superconductivity in two-dimensional XB_(2)(X=Si,Ge,Sn)monolayers via multicenter bonding
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作者 Wenyuan ZHANG Aitor BERGARA +1 位作者 Sheng WANG Guochun YANG 《Science China(Technological Sciences)》 2026年第2期220-228,共9页
Superconductivity in two-dimensional(2D)materials has attracted considerable attention due to their unique physical properties and potential for high-temperature operation.Boron-based 2D compounds are particularly pro... Superconductivity in two-dimensional(2D)materials has attracted considerable attention due to their unique physical properties and potential for high-temperature operation.Boron-based 2D compounds are particularly promising,thanks to their structural flexibility and the emergence of strong electron-phonon coupling(EPC)associated with light elements.While most previous studies have focused on stabilizing boron sheets through metal incorporation,we propose an alternative approach based on multicenter bonding enabled by group-IV non-metallic elements(Si,Ge,Sn).The resulting XB_(2)(X=Si,Ge,Sn)monolayers,which adopt a MgB_(2)-like monolayer configuration,are stabilized by a seven-center two-electron(7c-2e)bonding network between the X atoms and the boron honeycomb lattice.This bonding lowers the energy of the B-p_(z)orbitals and enhances lattice stability.The superconducting transition temperature(T_(c))increases significantly with the atomic number of X—from 4.7 K in SiB_(2)to 13.3 K in GeB_(2)and 24.9 K in SnB_(2)—driven by an increased carrier density near the Fermi level(E_(F))and softening of the high-frequency E_(2)phonon mode.Furthermore,we design a SnB_4 monolayer,in which a Sn layer is sandwiched between the two boron layers.This structure enriches in-plane phonon modes and strengthens EPC,yielding a T_(c)of 38 K,close to the McMillan limit.These findings highlight the critical role of multicenter bonding and targeted phonon engineering in enabling high-T_(c)2D boron-based superconductors. 展开更多
关键词 multicenter bonding first-principles calculations metallic covalent frameworks two-dimensional superconductivity
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Two-dimensional kagome semiconductor Sc_(6)S_(5)X_(6)(X=Cl,Br,I)with trilayer kagome lattice
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作者 Jin-Ling Yan Xing-Yu Wang +5 位作者 Gen-Ping Wu Hao Wang Ya-Jiao Ke Jiafu Wang Zhi-Hong Liu Jun-Hui Yuan 《Chinese Physics B》 2026年第2期519-528,共10页
Two-dimensional(2D)multilayer kagome materials hold significant research value for regulating kagome-related physical properties and exploring quantum effects.However,their development is hindered by the scarcity of a... Two-dimensional(2D)multilayer kagome materials hold significant research value for regulating kagome-related physical properties and exploring quantum effects.However,their development is hindered by the scarcity of available material systems,making the identification of novel 2D multilayer kagome candidates particularly important.In this work,three types of 2D materials with trilayer kagome lattices,namely Sc_(6)S_(5)X_(6)(X=Cl,Br,I),are predicted based on first-principles calculations.These 2D materials feature two kagome lattices composed of Sc atoms and one kagome lattice composed of S atoms.Stability analysis indicates that these materials can exist as free-standing 2D materials.Electronic structure calculations reveal that Sc_(6)S_(5)X_(6)are narrow-bandgap semiconductors(0.76–0.95 e V),with their band structures exhibiting flat bands contributed by Sc-based kagome lattices and Dirac band gaps resulting from symmetry breaking.The sulfur-based kagome lattice in the central layer contributes an independent flat band below the Fermi level.Additionally,Sc_(6)S_(5)X_(6)exhibit high carrier mobility,with hole and electron mobilities reaching up to 10^(3)cm^(2)·V^(-1)·s^(-1),indicating potential applications in low-dimensional electronic devices.This work provides an excellent example for the development of novel multilayer 2D kagome materials. 展开更多
关键词 multilayer kagome lattice two-dimensional materials carrier mobility first-principles calculations
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Synthesis of two-dimensional diamond by phase transition from graphene at atmospheric pressure
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作者 Songyang Li Zhiguang Zhu +2 位作者 Youzhi Zhang Chengke Chen Xiaojun Hu 《Chinese Physics B》 2025年第5期596-607,共12页
It is a key challenge to prepare two-dimensional diamond(2D-diamond).Herein,we develop a method for synthesizing 2D-diamond by depositing monodisperse tantalum(Ta)atoms onto graphene substrates using a hot-filament ch... It is a key challenge to prepare two-dimensional diamond(2D-diamond).Herein,we develop a method for synthesizing 2D-diamond by depositing monodisperse tantalum(Ta)atoms onto graphene substrates using a hot-filament chemical vapor deposition setup,followed by annealing treatment under different temperatures at ambient pressure.The results indicate that when the annealing temperature increases from 700℃ to 1000℃,the size of the 2D-diamond found in the samples gradually increases from close to 20 nm to around 30 nm.Meanwhile,the size and number of amorphous carbon spheres and Ta-containing compounds between the graphene layers gradually increase.As the annealing temperature continues to rise to 1100℃,a significant aggregation of Ta-containing compounds is observed in the samples,with no diamond structure detected.This further confirms that monodisperse Ta atoms play a key role in graphene phase transition into 2D-diamond.This study provides a novel method for the ambient-pressure phase transition of graphene into 2D-diamond. 展开更多
关键词 graphENE two-dimensional diamond vacuum annealing phase transition
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Mechanistic insights into water desalination through two-dimensional MXene-graphene oxide membranes:A molecular simulation study
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作者 Jie Liu Xiaoyan Tan +3 位作者 Yibo Xu Zijuan Li Yanan Xue Faquan Yu 《Chinese Journal of Chemical Engineering》 2025年第11期313-322,共10页
The emerging two-dimensional(2D)membranes offer a promising way to improve the water desalination performance of traditional membranes.MXene/graphene oxide(GO) composite membrane are known for their high separation pe... The emerging two-dimensional(2D)membranes offer a promising way to improve the water desalination performance of traditional membranes.MXene/graphene oxide(GO) composite membrane are known for their high separation performance and structural stability.In this study,molecular simulations are performed to investigate the desalination performance of the 2D MXene/GO membrane.The results reveal that the surface of the MXene nanosheet could induce the formation of ordered water structures,thereby accelerating the water transport in the 2D membrane.The higher rejection rate would be found in MXene/GO membrane with a larger GO oxidation degree owing to the sterichindrance effect induced by the functional groups on the GO surface.Overall,the MXene/GO(20) membrane with the interlayer spacing of 0.9 nm shows the highest water permeability(37.22×10^(-7)L·m^(-1)·h^(-1)·bar^(-1),1 bar=0.1 MPa)and a salt rejection of 100%.The results could provide theoretical insights for developing 2D membranes for water desalination. 展开更多
关键词 two-dimensional membrane MXene graphene oxide DESALINATION Molecular dynamics simulation
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Role of two-dimensional shear wave elastography in predicting posthepatectomy liver failure:A step forwards in hepatic surgery
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作者 Hua-Zhen Deng Yu-Feng Liu Han-Wen Zhang 《World Journal of Gastrointestinal Surgery》 2025年第3期415-417,共3页
This study explores the significance of using two-dimensional shear wave elastography(2D-SWE)to assess liver stiffness(LS)and spleen area(SPA)for predicting post-hepatectomy liver failure(PHLF).By providing a non-inva... This study explores the significance of using two-dimensional shear wave elastography(2D-SWE)to assess liver stiffness(LS)and spleen area(SPA)for predicting post-hepatectomy liver failure(PHLF).By providing a non-invasive method to measure LS,which correlates with the degree of liver fibrosis,and SPA,an indicator of portal hypertension,2D-SWE offers a comprehensive evaluation of a patient’s hepatic status.These advancements are particularly crucial in hepatic surgery,where accurate preoperative assessments are essential for optimizing surgical outcomes and minimizing complications.This letter highlights the prac-tical implications of integrating 2D-SWE into clinical practice,emphasizing its potential to improve patient safety and surgical precision by enhancing the ability to predict PHLF and tailor surgical approaches accordingly. 展开更多
关键词 two-dimensional shear wave elastography Liver stiffness Spleen area Post-hepatectomy liver failure Non-invasive techniques Hepatic surgery
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Trace component fishing strategy based on offline two-dimensional liquid chromatography combined with PRDX3-surface plasmon resonance for Uncaria alkaloids
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作者 Hui Ni Zijia Zhang +11 位作者 Ye Lu Yaowen Liu Yang Zhou Wenyong Wu Xinqin Kong Liling Shen Sihan Chen Huali Long Cheng Luo Hao Zhang Jinjun Hou Wanying Wu 《Journal of Pharmaceutical Analysis》 2025年第9期2135-2147,共13页
The rapid screening of bioactive constituents within traditional Chinese medicine(TCM)presents a significant challenge to researchers.Prevailing strategies for the screening of active components in TCM often overlook ... The rapid screening of bioactive constituents within traditional Chinese medicine(TCM)presents a significant challenge to researchers.Prevailing strategies for the screening of active components in TCM often overlook trace components owing to their concealment by more abundant constituents.To address this limitation,a fishing strategy based on offline two-dimensional liquid chromatography(2D-LC)combined with surface plasmon resonance(SPR)was utilized to screen bioactive trace components targeting peroxiredoxin 3(PRDX3),using Uncaria alkaloids(UAs)as a case study.Initially,an orthogonal preparative offline 2D-LC system combining a positively charged C_(18)column and a conventional C_(18)column under disparate mobile phase conditions was constructed.To fully reveal the trace alkaloids,132D fractions of UAs were prepared,and their components were characterized using mass spectrometry(MS).Subsequently,employing PRDX3 as the targeting protein,a SPR-based screening approach was established and rigorously validated with geissoschizine methyl ether(GSM)serving as a positive control for binding.Employing this refined strategy,29 candidate binding alkaloids were fished from the 132D fractions.Notably,combining offline 2D-LC with SPR increased the yield of candidate binding components from 10 to 29 when compared to SPR-based screening alone.Subsequent binding affinity assays confirmed that PRDX3 was a direct binding target for the 12 fished alkaloids,with isovallesiachotamine(IV),corynoxeine N-oxide(CO-N),and cadambine(CAD)demonstrating the highest affinity for PRDX3.Their interactions were further validated through molecular docking analysis.Subsequent intracellular H_(2)O_(2)measurement assays and transfection experiments confirmed that these three trace alkaloids enhanced PRDX3-mediated H_(2)O_(2)clearance.In conclusion,this study introduced an innovative strategy for the identification of active trace components in TCM.This approach holds promise for accelerating research on medicinal components within this field. 展开更多
关键词 Offline two-dimensional liquid chromatography Peroxiredoxin 3 Surface plasmon resonance Trace component fishing strategy Uncaria alkaloids
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Absolute band gaps in two-dimensional graphite photonic crystal 被引量:1
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作者 仇高新 林芳蕾 +1 位作者 王华 李永平 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第5期302-304,共3页
The off-plane propagation of electromagnetic (EM) waves in a two-dimensional (2D) graphite photonic crystal structure was studied using transfer matrix method. Transmission spectra calculations indicate that such a 2D... The off-plane propagation of electromagnetic (EM) waves in a two-dimensional (2D) graphite photonic crystal structure was studied using transfer matrix method. Transmission spectra calculations indicate that such a 2D structure has a common band gap from 0.202 to 0.2035 c/a for both H and E polarizations and for all off-plane angles form 0° up to 90°. The presence of such an absolute band gap implies that 2D graphite photonic crystal, which is much easier and more feasible to fabricate, can exhibit some properties of a three-dimensional (3D) photonic crystal. 展开更多
关键词 in on IT Absolute band gaps in two-dimensional graphite photonic crystal HAVE of been from
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基于SOP-Graph和AI辅助的职业教育课程开发:要义、框架与途径
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作者 向燕 郑洪波 《工业技术与职业教育》 2026年第1期78-82,共5页
提出了一种基于SOP-Graph(Standard Operating Procedure Graph)模型和AI技术的职业教育课程开发范式,旨在解决当前职业教育体系中标准更新滞后、课程内容脱节的问题。该范式的核心要义包括标准牵引与能力本位、任务化载体与“教学—学... 提出了一种基于SOP-Graph(Standard Operating Procedure Graph)模型和AI技术的职业教育课程开发范式,旨在解决当前职业教育体系中标准更新滞后、课程内容脱节的问题。该范式的核心要义包括标准牵引与能力本位、任务化载体与“教学—学习—评价一致性”、数据治理与敏捷迭代。基于这些要义,构建了“图谱化对齐—任务化同构—规则化协同—节拍化治理”的总体框架,并提出了包括入图建模、子图对齐、单元生成、版本管理等在内的六环节路径。结合OCR、命名实体识别(NER)和检索增强生成等AI技术,模型实现了从企业标准到能力、学习目标和教学评价的可计算映射与自动校验。相较于传统的以产出为导向的教育模式,本范式创新性地提出了以标准为源事实的溯源图谱与持续迭代的版本治理机制。研究的预期成果是促进“岗—课—赛—证”一体化,提升职业教育课程的应用性和可复制性,为职业教育的高质量发展提供技术支持。 展开更多
关键词 图谱建模 职业教育 课程开发 AI辅助
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Double contrast-enhanced two-dimensional and three-dimensional ultrasonography for evaluation of gastric lesions 被引量:39
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作者 Hong Shi Xiu-Hua Yu +7 位作者 Xin-Zhang Guo Yuan Guo Hong Zhang Bin Qian Zhang-Rui Wei Li Li Xian-Chen Wang Zi-Xiang Kong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第31期4136-4144,共9页
AIM: To investigate the value of two-dimensional (2D) and three-dimensional (3D) double contrast-enhanced ultrasonography (DCUS) imaging for evaluation of gas- tric lesions. METHODS: 2D and 3D DCUS imaging wit... AIM: To investigate the value of two-dimensional (2D) and three-dimensional (3D) double contrast-enhanced ultrasonography (DCUS) imaging for evaluation of gas- tric lesions. METHODS: 2D and 3D DCUS imaging with both oral and intravenous administrations of contrast agents was used to assess gastroscopiclly-confirmed gastric lesions in 46 patients with benign and malignant diseases. Initially, liquid-based ultrasound contrast agent (Xinzhang) was given orally at dose of 500-600 mL for conventional ultrasound examination of the gastric lesions, and then a microbubble-based contrast agent (SonoVue) was injected intravenously at dose of 1.2-2.4 mL in bolus fashion to assess the perfusion pattern of the lesions using contrast imaging modes. The parameters derived from time-intensity curves including the arrival time (AT), time to peak (lq-P), peak intensity (PI) and en- hanced intensity (EI) were measured on the 2D DCUS imaging. 3D DCUS of the lesions was acquired to dem- onstrate the value of this imaging mode. RESULTS: There were 22 cases with benign lesions including chronic gastritis (n= 5), gastric ulcer (n = 9), gastric polyps (n = 3), gastric stromal tumors (n = 5), and 24 cases with malignant lesions including gastric cancer (n = 20), gastric cardia carcinoma (n = 3) and post-operative recurrent gastric cancer (n = 1) in the study, The oral contrast-enhanced ultrasonography (CEUS) imaging of the stomach clearly demonstrated the anatomy of the stomach and morphologic features of gastric lesions, With optimal scanning window and imaging display under oral CEUS, intravenous CEUS clearly showed the perfusion of gastric lesions with various characteristic manifestations. Both 2D and 3D DCUS images clearly demonstrated normal gastric wall as a three-layer structure, from the inside out, hypere- choic mucosa, hypoechoic muscularis and hyperechoic serosa, respectively. There were statistical significant differences of AT (8.68±2.06 vs 10.43 ±2.75, P = 0.017), PI (34.64 ± 6.63 vs 29.58 ± 8.22, P = 0.023) and EI (29.72 ± 6.69 vs 22.66 ± 7.01, P = 0.001) between malignant lesions and normal gastric wall. However, no differences of AT, PI and EI between benign lesions and normal gastric wall tissue were found. 3D DCUS could intuitively display morphological features and vascularities of the lesions with multiplanar and volume views. 3D DCUS imaging provided comprehen- sive information complementary to 2D imaging. The crater or wellhead appearances and feeding vessels as well as distorted nourishing vasculature of gastric carcinoma were better seen with 3D imaging than 2D imaging. CONCLUSION: DCUS imaging can simultaneouslydisplay the anatomic and perfusion features of gastric lesions. 3D DCUS can provide additional information to 2D DCUS for evaluation of gastric lesions. 展开更多
关键词 Contrast-enhanced ultrasonography Gastriclesions two-dimensional imaging Three-dimensionalimaging Contrast media
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Two-Dimensional Graphs Moving by Mean Curvature Flow 被引量:7
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作者 CHEN Jing Yi Department of Mathematics.The University of British Columbia.Vancouver.B.C..Canada V6T 1Z2 E-mail:jychen@math.ubc.caLI Jia Yu Institute of Mathematics.Academy of Mathematics and System Sciences.Chinese Academy of Sciences.Beijing 100080.P.R.China Department of Mathematics.Fudan University.Shanghai 200433.P.R.China E-mail:lijia@math03.math.ac.cnTIAN Gang Department of Mathematics,MIT.Cambridge.MA 02139.U.S.A.E-mail:tian@math,mit.edu 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第2期209-224,共16页
A surface E is a graph in R^4 if there is a unit constant 2-form ω on R^4 such that <e_1∧e_2.ω>≥v_0>0 where{e_1.e_2}is an orthonormal frame on Σ.We prove that.if v_0≥on the initial snrface,then the mean... A surface E is a graph in R^4 if there is a unit constant 2-form ω on R^4 such that <e_1∧e_2.ω>≥v_0>0 where{e_1.e_2}is an orthonormal frame on Σ.We prove that.if v_0≥on the initial snrface,then the mean curvature flow has a global solution and the scaled surfaces converge to a self-similar solution.A surface Σ is a graph in M_1×M_2 where M_1 and M_2 are Riemann surfaces. if<e_1∧e_2.ω>≥v_0>0 where w_1 is a Khler form on M_1.We prove that.if M is a Khler-Einstein surface with scalar curvature R.v_0≥ on the initial surface,then the mean curvature flow has a global solution and it sub-converges to a minimal surface,if.in addition.R≥0 it converges to a totally geodesic surface which is holomorphic. 展开更多
关键词 Mean curvature flow 2-dimensional graphs in R^4 Self-similar solution
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Wearable Biodevices Based on Two-Dimensional Materials:From Flexible Sensors to Smart Integrated Systems 被引量:1
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作者 Yingzhi Sun Weiyi He +3 位作者 Can Jiang Jing Li Jianli Liu Mingjie Liu 《Nano-Micro Letters》 2025年第5期207-255,共49页
The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an over... The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an overwhelming tendency,providing powerful tools for remote health monitoring and personal health management.Among many candidates,two-dimensional(2D)materials stand out due to several exotic mechanical,electrical,optical,and chemical properties that can be efficiently integrated into atomic-thin films.While previous reviews on 2D materials for biodevices primarily focus on conventional configurations and materials like graphene,the rapid development of new 2D materials with exotic properties has opened up novel applications,particularly in smart interaction and integrated functionalities.This review aims to consolidate recent progress,highlight the unique advantages of 2D materials,and guide future research by discussing existing challenges and opportunities in applying 2D materials for smart wearable biodevices.We begin with an in-depth analysis of the advantages,sensing mechanisms,and potential applications of 2D materials in wearable biodevice fabrication.Following this,we systematically discuss state-of-the-art biodevices based on 2D materials for monitoring various physiological signals within the human body.Special attention is given to showcasing the integration of multi-functionality in 2D smart devices,mainly including self-power supply,integrated diagnosis/treatment,and human–machine interaction.Finally,the review concludes with a concise summary of existing challenges and prospective solutions concerning the utilization of2D materials for advanced biodevices. 展开更多
关键词 two-dimensional material Wearable biodevice Flexible sensor Smart integrated system Healthcare
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Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng 被引量:13
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作者 Tiantian Zuo Chunxia Zhang +7 位作者 Weiwei Li Hongda Wang Ying Hu Wenzhi Yang Li Jia Xiaoyan Wang Xiumei Gao Dean Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期597-609,共13页
Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensi... Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites. 展开更多
关键词 Dimension-enhanced strategy Multicomponent characterization GINSENOSIDE Offline two-dimensional liquid chromatography Ion mobility-quadrupole time-of-flight mass spectrometry In-house database
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Graphene-like two-dimensional nanosheets-based anticorrosive coatings: A review 被引量:5
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作者 Yumin Zhang Jiulong Sun +3 位作者 Xinzhe Xiao Ning Wang Guozhe Meng Lin Gu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第34期139-162,共24页
In recent years, graphene has been widely employed in the field of metal corrosion protection owing to its outstanding impermeability and chemical stability, with examples of such metal protection including pure graph... In recent years, graphene has been widely employed in the field of metal corrosion protection owing to its outstanding impermeability and chemical stability, with examples of such metal protection including pure graphene coatings and graphene-based composite coatings. But the conductive graphene could promote the electrochemical reaction at the interface and accelerate the corrosion of metal substrates. More emerging graphene-like 2D nanosheets are attracting research attention for the application of metal anticorrosion, because of their barrier properties and poor conductivity, mainly including boron nitride(BN),molybdenum disulfide(MoS_(2)), zirconium phosphate(ZrP), and titanium carbide(MXene). In this review,the application of these graphene-like 2D nanosheets to metal protection is comprehensively reviewed.First, the general preparation methods of 2D nanosheets are briefly introduced. Second, surface functionalization of 2D nanosheets, including covalent and non-covalent modification, is described in detail.Third, the anticorrosion performance and optimization measures of pure 2D nanosheets coatings are summarized. Next, the protection performance, anticorrosive mechanism, and optimizations of 2D nanosheets composite coatings are presented. Finally, the future development of 2D nanosheets-based anticorrosive coatings has been prospected, and the challenges in the industrial application are discussed. 展开更多
关键词 two-dimensional nanomaterials Surface functionalization Polymer composite coatings Metal Corrosion protection
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Enhanced formaldehyde sensitivity of two-dimensional mesoporous SnO_(2) by nitrogen-doped graphene quantum dots 被引量:6
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作者 Zhen-Lu Chen Ding Wang +1 位作者 Xian-Ying Wang Jun-He Yang 《Rare Metals》 SCIE EI CAS CSCD 2021年第6期1561-1570,共10页
Formaldehyde(HCHO) is widely known as an indoor air pollutant,and the monitoring of the gas has significant importance.However,most HCHO sensing materials do not have low detection limits and operate at high temperatu... Formaldehyde(HCHO) is widely known as an indoor air pollutant,and the monitoring of the gas has significant importance.However,most HCHO sensing materials do not have low detection limits and operate at high temperatures.Herein,two-dimensional(2D) mesoporous ultrathin SnO_(2) modified with nitrogen-doped graphene quantum dots(N-GQDs) was synthesized.The N-GQDs/SnO_(2) nanocomposite demonstrated high efficiency for HCHO detection.With the addition of 1.00 wt%N-GQDs,the response(Ra/Rg) of SnO_(2) gas sensor increased from 120 to 361 at 60℃ for the detection of 10×10^(-6) HCHO.In addition,the corresponding detection limit was as low as 10×10^(-9).Moreover,the sensor exhibited excellent selectivity and stability for the detection of HCHO.The enhanced sensing performance was attributed to both the large specific surface area of SnO_(2) and electron regulation of N-GQDs.Therefore,this study presents a novel HCHO sensor,and it expands the research and application potential of GQDs nanocomposites. 展开更多
关键词 Nitrogen-doped graphene quantum dots Formaldehyde sensor two-dimensional SnO_(2) Nanocomposites
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Differential diagnosis of different types of solid focal liver lesions using two-dimensional shear wave elastography 被引量:6
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作者 Jia Guo Dong Jiang +4 位作者 Yi Qian Jiao Yu Yi-Jun Gu Yu-Qing Zhou Hui-Ping Zhang 《World Journal of Gastroenterology》 SCIE CAS 2022年第32期4715-4724,共10页
BACKGROUND The clinical management and prognosis differ between benign and malignant solid focal liver lesions(FLLs),as well as among different pathological types of malignant FLLs.Accurate diagnosis of the possible t... BACKGROUND The clinical management and prognosis differ between benign and malignant solid focal liver lesions(FLLs),as well as among different pathological types of malignant FLLs.Accurate diagnosis of the possible types of solid FLLs is important.Our previous study confirmed the value of shear wave elastography(SWE)using maximal elasticity(Emax)as the parameter in the differential diagnosis between benign and malignant FLLs.However,the value of SWE in the differential diagnosis among different pathological types of malignant FLLs has not been proved.AIM To explore the value of two-dimensional SWE(2D-SWE)using Emax in the differential diagnosis of FLLs,especially among different pathological types of malignant FLLs.METHODS All the patients enrolled in this study were diagnosed as benign,malignant or undetermined FLLs by conventional ultrasound.Emax of FLLs and the periphery of FLLs was measured using 2D-SWE and compared between benign and malignant FLLs or among different pathological types of malignant FLLs.RESULTS The study included 32 benign FLLs in 31 patients and 100 malignant FLLs in 96 patients,including 16 cholangiocellular carcinomas(CCCs),72 hepatocellular carcinomas(HCCs)and 12 liver metastases.Thirty-five FLLs were diagnosed as undetermined by conventional ultrasound.There were significant differences between Emax of malignant(2.21±0.57 m/s)and benign(1.59±0.37 m/s)FLLs(P=0.000),and between Emax of the periphery of malignant(1.52±0.39 m/s)and benign(1.36±0.44 m/s)FLLs(P=0.040).Emax of liver metastases(2.73±0.99 m/s)was significantly higher than that of CCCs(2.14±0.34 m/s)and HCCs(2.14±0.46 m/s)(P=0.002).The sensitivity,specificity and accuracy were 71.00%,84.38%and 74.24%respectively,using Emax>1.905 m/s(AUC 0.843)to diagnose as malignant and 23 of 35(65.74%)FLLs with undetermined diagnosis by conventional ultrasound were diagnosed correctly.CONCLUSION Malignant FLLs were stiffer than benign ones and liver metastases were stiffer than primary liver carcinomas.2D-SWE with Emax was a useful complement to conventional ultrasound for the differential diagnosis of FLLs. 展开更多
关键词 Focal liver lesions Conventional ultrasound two-dimensional shear wave elastography Differential diagnosis
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