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Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response 被引量:3
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作者 Xiaojun Zeng Xiao Jiang +2 位作者 Ya Ning Yanfeng Gao Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期453-473,共21页
The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterost... The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities. 展开更多
关键词 Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption
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Electron-distribution control via Pt/NC and MoC/NC dual junction:Boosted hydrogen electro-oxidation and theoretical study 被引量:1
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作者 Feng Zhou Xiaofeng Ke +8 位作者 Yihuang Chen Mei Zhao Yun Yang Youqing Dong Chao Zou Xi’an Chen Huile Jin Lijie Zhang Shun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期513-520,I0011,共9页
The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to ... The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO. 展开更多
关键词 Hydrogen oxidation reaction Dual junctions CO-tolerance PLATINUM
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Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers 被引量:1
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作者 Kaiwen Lei Hao Wu +4 位作者 Jerry W Spears Xi Lin Xi Wang Xue Bai Yanling Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1329-1337,共9页
This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.... This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein. 展开更多
关键词 IRON yellow-feathered broiler antioxidant function intestinal morphology tight junction protein
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Early adenocarcinoma mixed with a neuroendocrine carcinoma component arising in the gastroesophageal junction: A case report 被引量:1
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作者 Yu-Qing Cheng Geng-Fang Wang +3 位作者 Xiao-Li Zhou Min Lin Xin-Wen Zhang Qin Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期563-570,共8页
BACKGROUND Early adenocarcinoma mixed with a neuroendocrine carcinoma(NEC)component arising in the gastroesophageal junctional(GEJ)region is rare and even rarer in young patients.Here,we report such a case in a 29-yea... BACKGROUND Early adenocarcinoma mixed with a neuroendocrine carcinoma(NEC)component arising in the gastroesophageal junctional(GEJ)region is rare and even rarer in young patients.Here,we report such a case in a 29-year-old Chinese man.CASE SUMMARY This patient presented to our hospital with a 3-mo history of dysphagia and regurgitation.Upper endoscopy revealed an elevated nodule in the distal esophagus 1.6 cm above the GEJ line,without Barrett’s esophagus or involvement of the gastric cardia.The nodule was completely resected by endoscopic submu-cosal dissection(ESD).Pathological examination confirmed diagnosis of intra-mucosal adenocarcinoma mixed with an NEC component,measuring 1.5 cm.Immunohistochemically,both adenocarcinoma and NEC components were positive for P53 with a Ki67 index of 90%;NEC was positive for synaptophysin and chromogranin.Next-generation sequencing of 196 genes demonstrated a novel germline mutation of the ERCC3 gene in the DNA repair pathway and a germline mutation of the RNF43 gene,a common gastric cancer driver gene,in addition to pathogenic somatic mutations in P53 and CHEK2 genes.The patient was alive without evidence of the disease 36 mo after ESD.CONCLUSION Early adenocarcinoma with an NEC component arising in the distal esophageal side of the GEJ region showed evidence of gastric origin. 展开更多
关键词 ADENOCARCINOMA Neuroendocrine carcinoma Gastroesophageal junction Next generation sequencing Case report
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Co-doped BaFe_(2)As_(2) Josephson junction fabricated with a focused helium ion beam 被引量:1
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作者 陈紫雯 张焱 +6 位作者 马平 徐中堂 李宇龙 王越 路建明 马衍伟 甘子钊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期181-186,共6页
Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation ... Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation of high-quality iron pnictide Josephson junctions is of great importance.In this work,we have successfully fabricated Josephson junctions from Co-doped BaFe_(2)As_(2)thin films using a direct junction fabrication technique which utilizes high energy focused helium ion beam(FHIB).The electrical transport properties were investigated for junctions fabricated with various He^(+)irradiation doses.The junctions show sharp superconducting transition around 24 K with a narrow transition width of 2.5 K,and a dose correlated foot-structure resistance which corresponds to the effective tuning of junction properties by He^(+)irradiation.Significant J_c suppression by more than two orders of magnitude can be achieved by increasing the He^(+)irradiation dose,which is advantageous for the realization of low noise ion pnictide thin film devices.Clear Shapiro steps are observed under 10 GHz microwave irradiation.The above results demonstrate the successful fabrication of high quality and controllable Co-doped BaFe_(2)As_(2)Josephson junction with high reproducibility using the FHIB technique,laying the foundation for future investigating the mechanism of iron-based superconductors,and also the further implementation in various superconducting electronic devices. 展开更多
关键词 focused helium ion beam Co doped BaFe_(2)As_(2) Josephson junction
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Computed tomography-based nomogram of Siewert type Ⅱ/Ⅲ adenocarcinoma of esophagogastric junction to predict response to docetaxel, oxaliplatin and S-1 被引量:1
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作者 Chuan-Qinyuan Zhou Dan Gao +7 位作者 Yan Gui Ning-Pu Li Wen-Wen Guo Hai-Ying Zhou Rui Li Jing Chen Xiao-Ming Zhang Tian-Wu Chen 《World Journal of Radiology》 2024年第1期9-19,共11页
BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on ba... BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on baseline computed tomography(CT)to predict response of Siewert type II or III AEG to NAC with docetaxel,oxaliplatin and S-1(DOS).AIM To develop a CT-based nomogram to predict response of Siewert type II/III AEG to NAC with DOS.METHODS One hundred and twenty-eight consecutive patients with confirmed Siewert type II/III AEG underwent CT before and after three cycles of NAC with DOS,and were randomly and consecutively assigned to the training cohort(TC)(n=94)and the validation cohort(VC)(n=34).Therapeutic effect was assessed by disease-control rate and progressive disease according to the Response Evaluation Criteria in Solid Tumors(version 1.1)criteria.Possible prognostic factors associated with responses after DOS treatment including Siewert classification,gross tumor volume(GTV),and cT and cN stages were evaluated using pretherapeutic CT data in addition to sex and age.Univariate and multivariate analyses of CT and clinical features in the TC were performed to determine independent factors associated with response to DOS.A nomogram was established based on independent factors to predict the response.The predictive performance of the nomogram was evaluated by Concordance index(C-index),calibration and receiver operating characteristics curve in the TC and VC.RESULTS Univariate analysis showed that Siewert type(52/55 vs 29/39,P=0.005),pretherapeutic cT stage(57/62 vs 24/32,P=0.028),GTV(47.3±27.4 vs 73.2±54.3,P=0.040)were significantly associated with response to DOS in the TC.Multivariate analysis of the TC also showed that the pretherapeutic cT stage,GTV and Siewert type were independent predictive factors related to response to DOS(odds ratio=4.631,1.027 and 7.639,respectively;all P<0.05).The nomogram developed with these independent factors showed an excellent performance to predict response to DOS in the TC and VC(C-index:0.838 and 0.824),with area under the receiver operating characteristic curve of 0.838 and 0.824,respectively.The calibration curves showed that the practical and predicted response to DOS effectively coincided.CONCLUSION A novel nomogram developed with pretherapeutic cT stage,GTV and Siewert type predicted the response of Siewert type II/III AEG to NAC with DOS. 展开更多
关键词 Esophagogastric junction ADENOCARCINOMA Neoadjuvant chemotherapy RESPONSE Tomography X-ray computed Predictor
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Electronic properties of 2D materials and their junctions
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作者 Taposhree Dutta Neha Yadav +8 位作者 Yongling Wu Gary J.Cheng Xiu Liang Seeram Ramakrishna Aoussaj Sbai Rajeev Gupta Aniruddha Mondal Zheng Hongyu Ashish Yadav 《Nano Materials Science》 EI CAS CSCD 2024年第1期1-23,共23页
With an extensive range of distinctive features at nano meter-scale thicknesses,two-dimensional(2D)materials drawn the attention of the scientific community.Despite tremendous advancements in exploratory research on 2... With an extensive range of distinctive features at nano meter-scale thicknesses,two-dimensional(2D)materials drawn the attention of the scientific community.Despite tremendous advancements in exploratory research on 2D materials,knowledge of 2D electrical transport and carrier dynamics still in its infancy.Thus,here we highlighted the electrical characteristics of 2D materials with electronic band structure,electronic transport,dielectric constant,carriers mobility.The atomic thinness of 2D materials makes substantially scaled field-effect transistors(FETs)with reduced short-channel effects conceivable,even though strong carrier mobility required for high performance,low-voltage device operations.We also discussed here about factors affecting 2D materials which easily enhanced the activity of those materials for various applications.Presently,Those 2D materials used in state-of-the-art electrical and optoelectronic devices because of the extensive nature of their electronic band structure.2D materials offer unprecedented freedom for the design of novel p-n junction device topologies in contrast to conventional bulk semiconductors.We also,describe the numerous 2D p-n junctions,such as homo junction and hetero junction including mixed dimensional junctions.Finally,we talked about the problems and potential for the future. 展开更多
关键词 2D materials Electrical properties p-n junctions Mixed hereto junctions Homo junctions Electrical transport
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High-performance GaSb planar PN junction detector
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作者 Yuanzhi Cui Hongyue Hao +13 位作者 Shihao Zhang Shuo Wang Jing Zhang Yifan Shan Ruoyu Xie Xiaoyu Wang Chuang Wang Mengchen Liu Dongwei Jiang Yingqiang Xu Guowei Wang Donghai Wu Zhichuan Niu Derang Cao 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期48-52,共5页
This paper examines GaSb short-wavelength infrared detectors employing planar PN junctions. The fabrication was based on the Zn diffusion process and the diffusion temperature was optimized. Characterization revealed ... This paper examines GaSb short-wavelength infrared detectors employing planar PN junctions. The fabrication was based on the Zn diffusion process and the diffusion temperature was optimized. Characterization revealed a 50% cut-off wavelength of 1.73 μm, a maximum detectivity of 8.73 × 10^(10) cm·Hz^(1/2)/W, and a minimum dark current density of 1.02 × 10^(-5) A/cm^(2).Additionally, a maximum quantum efficiency of 60.3% was achieved. Subsequent optimization of fabrication enabled the realization of a 320 × 256 focal plane array that exhibited satisfactory imaging results. Remarkably, the GaSb planar detectors demonstrated potential in low-cost short wavelength infrared imaging, without requiring material epitaxy or deposition. 展开更多
关键词 ANTIMONIDE short-wave infrared planar junction zinc diffusion
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Anisotropic spin transport and photoresponse characteristics detected by tip movement in magnetic single-molecule junction
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作者 陈登辉 羊志 +5 位作者 付新宇 秦申奥 严岩 王传奎 李宗良 邱帅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期640-648,共9页
Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule junctions.Here,using the first-principles method,we theoretically investigate spin transport properties and p... Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule junctions.Here,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact sites.The transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright geometry.The maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin polarization.Our theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules. 展开更多
关键词 molecular spintronics spin polarization tunneling magnetoresistance PHOTOCURRENT single-molecule junctions
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In situ non-destructive measurement of Josephson junction resistance using fritting contact technique
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作者 Lei Du Hao-Ran Tao +7 位作者 Liang-Liang Guo Hai-Feng Zhang Yong Chen Xin Tian Chi Zhang Zhi-Long Jia Peng Duan Guo-Ping Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期57-61,共5页
Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we pr... Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing. 展开更多
关键词 NON-DESTRUCTIVE fritting contact qubit frequency Josephson junction resistance
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Recent developments in superjunction power devices
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作者 Chao Ma Weizhong Chen +2 位作者 Teng Liu Wentong Zhang Bo Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第11期18-35,共18页
Abstract:Superjunction(SJ)is one of the most innovative concepts in the field of power semiconductor devices and is often referred to as a"milestone"in power MOS.Its balanced charge field modulation mechanis... Abstract:Superjunction(SJ)is one of the most innovative concepts in the field of power semiconductor devices and is often referred to as a"milestone"in power MOS.Its balanced charge field modulation mechanism breaks through the strong dependency between the doping concentration in the drift region and the breakdown voltage V_(B)in conventional devices.This results in a reduction of the trade-off relationship between specific on-resistance R_(on,sp)and V_(B)from the conventional R_(on,sp)∝V_(B)^(2.5)to R_(on,sp)∝W·V_(B)^(1.32),and even to R_(on,sp)∝W·V_(B)^(1.03).As the exponential term coefficient decreases,R_(on,sp)decreases with the cell width W,exhibiting a development pattern reminiscent of"Moore's Law".This paper provides an overview of the latest research developments in SJ power semiconductor devices.Firstly,it introduces the minimum specific on-resistance R_(on,min)theory of SJ devices,along with its combination with special effects like 3-D depletion and tunneling,discussing the development of R_(on,min)theory in the wide bandgap SJ field.Subsequently,it discusses the latest advancements in silicon-based and wide bandgap SJ power devices.Finally,it introduces the homogenization field(HOF)and high-K voltage-sustaining layers derived from the concept of SJ charge balance.SJ has made significant progress in device performance,reliability,and integration,and in the future,it will continue to evolve through deeper integration with different materials,processes,and packaging technologies,enhancing the overall performance of semiconductor power devices. 展开更多
关键词 super junction silicon limit power semiconductor device design theory
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Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution
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作者 Lifang Ge Meizhen Gao +3 位作者 Xiaosheng Zhang Jiang Wang Qi Shi Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期90-100,共11页
The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic ... The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic imidazolate frameworks(ZIFs) with chabazite(CHA) topology for separation of 2,3-butanediol(2,3-BDO) and 1,3-propanediol(1,3-PDO), which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule. Based on CHA-ZIFs with the same small-sized ligand 2-methylimidazole(mIm) and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process. We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments. But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups. For a typical ZIF-301, its adsorption capacity for 2,3-BDO was 116.4 mg·g^(-1)and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binary-component system(2,3-BDO/1,3-PDO: 50 g·L^(-1)/50 g·L^(-1)). Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong host-guest interactions. Therefore, the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO, which also provided a new perspective for separating diols in dilute aqueous solutions. 展开更多
关键词 Adsorption Separation Aqueous solution Zeolitic imidazolate frameworks junctional and hydrophobic trap DIOLS
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Terahertz high-sensitivity SIS mixer based on Nb–AlN–NbN hybrid superconducting tunnel junctions
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作者 刘博梁 刘冬 +8 位作者 姚明 金骏达 王争 李婧 史生才 Artem Chekushkin Michael Fominsky Lyudmila Filippenko Valery Koshelets 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期681-686,共6页
The terahertz band,a unique segment of the electromagnetic spectrum,is crucial for observing the cold,dark universe and plays a pivotal role in cutting-edge scientific research,including the study of cosmic environmen... The terahertz band,a unique segment of the electromagnetic spectrum,is crucial for observing the cold,dark universe and plays a pivotal role in cutting-edge scientific research,including the study of cosmic environments that support life and imaging black holes.High-sensitivity superconductor–insulator–superconductor(SIS)mixers are essential detectors for terahertz astronomical telescopes and interferometric arrays.Compared to the commonly used classical Nb/AlO_(x)/Nb superconducting tunnel junction,the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current density.This makes it particularly promising for the development of ultra-wideband,high-sensitivity coherent detectors or mixers in various scientific research fields.In this paper,we present a superconducting SIS mixer based on Nb/AlN/NbN parallel-connected twin junctions(PCTJ),which has a bandwidth extending up to490 GHz–720 GHz.The best achieved double-sideband(DSB)noise temperature(sensitivity)is below three times the quantum noise level. 展开更多
关键词 SIS mixer TERAHERTZ gap voltage critical current density hybrid superconducting tunnel junction
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Electrical properties and structural optimization of GaN/InGaN/GaN tunnel junctions grown by molecular beam epitaxy
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作者 Jun Fang Fan Zhang +4 位作者 Wenxian Yang Aiqin Tian Jianping Liu Shulong Lu Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期48-54,共7页
The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases an... The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases and the surface roughness of the samples increases.V-pits and trench defects were not found in the AFM images.p++-GaN/InGaN/n++-GaN TJs were investigated for various In content,InGaN thicknesses and doping concentration in the InGaN insert layer.The InGaN insert layer can promote good interband tunneling in GaN/InGaN/GaN TJ and significantly reduce operating voltage when doping is sufficiently high.The current density increases with increasing In content for the 3 nm InGaN insert layer,which is achieved by reducing the depletion zone width and the height of the potential barrier.At a forward current density of 500 A/cm^(2),the measured voltage was 4.31 V and the differential resistance was measured to be 3.75×10^(−3)Ω·cm^(2)for the device with a 3 nm p++-In_(0.35)Ga_(0.65)N insert layer.When the thickness of the In_(0.35)Ga_(0.65)N layer is closer to the“balanced”thickness,the TJ current density is higher.If the thickness is too high or too low,the width of the depletion zone will increase and the current density will decrease.The undoped InGaN layer has a better performance than n-type doping in the TJ.Polarization-engineered tunnel junctions can enhance the functionality and performance of electronic and optoelectronic devices. 展开更多
关键词 GaN/InGaN/GaN tunnel junctions polarization-engineering molecular beam epitaxy
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Research status and hotspots of tight junctions and colorectal cancer:A bibliometric and visualization analysis
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作者 Hui-Min Li Yin Liu +5 位作者 Meng-Di Hao Xiao-Qing Liang Da-Jin Yuan Wen-Bin Huang Wen-Jie Li Lei Ding 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3705-3715,共11页
BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding... BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding the role of tight junction(TJ)proteins in the occurrence and progression of CRC.The causal relationship between the presence of specific TJ proteins and the development of CRC has also been confirmed.Despite the large number of publications in this field,a bibliometric study to review the current state of research and highlight the research trends and hotspots in this field has not yet been performed.AIM To analyze research on TJs and CRC,summarize the field’s history and current status,and predict future research directions.METHODS We searched the Science Citation Index Expanded database for all literature on CRC and TJs from 2001-2023.We used bibliometrics to analyze the data of these papers,such as the authors,countries,institutions,and references.Co-authorship,co-citation,and co-occurrence analyses were the main methods of analysis.CiteSpace and VOSviewer were used to visualize the results.RESULTS A total of 205 studies were ultimately identified.The number of publications on this topic has steadily increased since 2007.China and the United States have made the largest contributions to this field.Anticancer Research was the most prolific journal,publishing 8 articles,while the journal Oncogene had the highest average citation rate(68.33).Professor Dhawan P was the most prolific and cited author in this field.Co-occurrence analysis of keywords revealed that“tight junction protein expression”,“colorectal cancer”,“intestinal microbiota”,and“inflammatory bowel disease”had the highest frequency of occurrence,revealing the research hotspots and trends in this field.CONCLUSION This bibliometric analysis evaluated the scope and trends of TJ proteins in CRC,providing valuable research perspectives and future directions for studying the connection between the two.It is recommended to focus on emerging research hotspots,such as the correlations among intestinal microbiota,inflammatory bowel disease,TJ protein expression,and CRC. 展开更多
关键词 Colorectal cancer Tight junctions Bibliometric analysis Research trends Hot spots
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Development of a novel staging classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction after neoadjuvant chemotherapy
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作者 Jian Zhang Hao Liu +1 位作者 Hang Yu Wei-Xiang Xu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2541-2554,共14页
BACKGROUND Stage classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction(AEG)treated with neoadjuvant chemotherapy(NAC)has not been established.AIM To investigate the optimal stage classification ... BACKGROUND Stage classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction(AEG)treated with neoadjuvant chemotherapy(NAC)has not been established.AIM To investigate the optimal stage classification for Siewert Ⅱ AEG with NAC.METHODS A nomogram was established based on Cox regression model that analyzed variables associated with overall survival(OS)and disease-specific survival(DSS).The nomogram performance in terms of discrimination and calibration ability was evaluated using the likelihood-ratio test,Akaike information criterion,Harrell concordance index,time-receiver operating characteristic curve,and decision curve analysis.RESULTS Data from 725 patients with Siewert type Ⅱ AEG who underwent neoadjuvant therapy and gastrectomy were obtained from the Surveillance,Epidemiology,and End Results database.Univariate and multivariate analyses revealed that sex,marital status,race,ypT stage,and ypN stage were independent prognostic factors of OS,whereas sex,race,ypT stage,and ypN stage were independent prognostic factors for DSS.These factors were incorporated into the OS and DSS nomograms.Our novel nomogram model performed better in terms of OS and DSS prediction compared to the 8th American Joint Committee of Cancer pathological staging system for esophageal and gastric cancer.Finally,a user-friendly web application was developed for clinical use.CONCLUSION The nomogram established specifically for patients with Siewert type Ⅱ AEG receiving NAC demonstrated good prognostic performance.Validation using external data is warranted before its widespread clinical application. 展开更多
关键词 Stage classification PROGNOSIS Esophagogastric junction cancer Neoadjuvant chemotherapy Siewert type
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Half-integer Shapiro steps in MgB_(2) focused He ion beam Josephson junctions
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作者 殷大利 蔡欣炜 +5 位作者 徐铁权 孙瑞宁 韩颖 张焱 王越 甘子钊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期483-489,共7页
Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(C... Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical properties.In this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson junctions.The half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also analyzed.We find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is discussed.As a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'array.Our results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors. 展开更多
关键词 Josephson junction half-integer Shapiro steps MgB_(2) focused helium ion beam
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Prognostic nutritional index in predicting survival of patients with gastric or gastroesophageal junction adenocarcinoma: A systematic review
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作者 Stylianos Fiflis Grigorios Christodoulidis +6 位作者 Menelaos Papakonstantinou Alexandros Giakoustidis Stergos Koukias Paraskevi Roussos Marina Nektaria Kouliou Konstantinos Eleftherios Koumarelas Dimitrios Giakoustidis 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期514-526,共13页
BACKGROUND Gastric cancer is the third most common cause of cancer related death worldwide.Surgery with or without chemotherapy is the most common approach with curative intent;however,the prognosis is poor as mortali... BACKGROUND Gastric cancer is the third most common cause of cancer related death worldwide.Surgery with or without chemotherapy is the most common approach with curative intent;however,the prognosis is poor as mortality rates remain high.Several indexes have been proposed in the past few years in order to estimate the survival of patients undergoing gastrectomy.The preoperative nutritional status of gastric cancer patients has recently gained attention as a factor that could affect the postoperative course and various indexes have been developed.The aim of this systematic review was to assess the role of the prognostic nutritional index(PNI)in predicting the survival of patients with gastric or gastroesophageal adenocarcinoma who underwent gastrectomy with curative intent.AIM To investigate the role of PNI in predicting the survival of patients with gastric or gastroesophageal junction adenocarcinoma.METHODS A thorough literature search of PubMed and the Cochrane library was performed for studies comparing the overall survival(OS)of patients with gastric or gastroesophageal cancer after surgical resection depending on the preoperative PNI value.The PRISMA algorithm was used in the screening process and finally 16 studies were included in this systematic review.The review protocol was registered in the International Prospective Register of Systematic Reviews(PRO) RESULTS Sixteen studies involving 14551 patients with gastric or esophagogastric junction adenocarcinoma undergoing open or laparoscopic or robotic gastrectomy with or without adjuvant chemotherapy were included in this systematic review.The patients were divided into high-and low-PNI groups according to cut-off values that were set according to previous reports or by using receiver operating characteristic curve analysis in each individual study.The 5-year OS of patients in the low-PNI groups ranged between 39%and 70.6%,while in the high-PNI groups,it ranged between 54.9%and 95.8%.In most of the included studies,patients with high preoperative PNI showed statistically significant better OS than the low PNI groups.In multivariate analyses,low PNI was repeatedly recognised as an independent prognostic factor for poor survival.CONCLUSION According to the present study,low preoperative PNI seems to be an indicator of poor OS of patients undergoing gastrectomy for gastric or gastroesophageal cancer. 展开更多
关键词 Prognostic nutritional index Gastric adenocarcinoma Gastroesophageal junction cancer PROGNOSIS Overall survival
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Patient-derived induced pluripotent stem cells with a MERTK mutation exhibit cell junction abnormalities and aberrant cellular differentiation potential
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作者 Hang Zhang Ling-Zi Wu +1 位作者 Zhen-Yu Liu Zi-Bing Jin 《World Journal of Stem Cells》 SCIE 2024年第5期512-524,共13页
BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease mechanisms.However,iPSCs carrying ... BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease mechanisms.However,iPSCs carrying specific mutations may limit their clinical applications due to certain inherent characteristics.AIM To investigate the impact of MERTK mutations on hiPSCs and determine whether hiPSC-derived extracellular vesicles(EVs)influence anomalous cell junction and differentiation potential.METHODS We employed a non-integrating reprogramming technique to generate peripheral blood-derived hiPSCs with and hiPSCs without a MERTK mutation.Chromo-somal karyotype analysis,flow cytometry,and immunofluorescent staining were utilized for hiPSC identification.Transcriptomics and proteomics were employed to elucidate the expression patterns associated with cell junction abnormalities and cellular differentiation potential.Additionally,EVs were isolated from the supernatant,and their RNA and protein cargos were examined to investigate the involvement of hiPSC-derived EVs in stem cell junction and differentiation.RESULTS The generated hiPSCs,both with and without a MERTK mutation,exhibited normal karyotype and expressed pluripotency markers;however,hiPSCs with a MERTK mutation demonstrated anomalous adhesion capability and differentiation potential,as confirmed by transcriptomic and proteomic profiling.Furthermore,hiPSC-derived EVs were involved in various biological processes,including cell junction and differentiation.CONCLUSION HiPSCs with a MERTK mutation displayed altered junction characteristics and aberrant differentiation potential.Furthermore,hiPSC-derived EVs played a regulatory role in various biological processes,including cell junction and differentiation. 展开更多
关键词 Cell junction Cellular differentiation Extracellular vesicle Human induced pluripotent stem cells TRANSCRIPTOMICS Proteomics
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Light-modulated graphene-based φ_(0) Josephson junction and -φ_(0) to φ_(0) transition
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作者 程任翔 于苗 +4 位作者 汪洪 曹德亮 李兴鳌 戚凤华 周兴飞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期476-481,共6页
We investigate the chiral edge states-induced Josephson current–phase relation in a graphene-based Josephson junction modulated by the off-resonant circularly polarized light and the staggered sublattice potential.By... We investigate the chiral edge states-induced Josephson current–phase relation in a graphene-based Josephson junction modulated by the off-resonant circularly polarized light and the staggered sublattice potential.By solving the Bogoliubov–de Gennes equation,a φ_(0) Josephson junction is induced in the coaction of the off-resonant circularly polarized light and the staggered sublattice potential,which arises from the fact that the center of-mass wave vector of Cooper pair becomes finite and the opposite center of-mass wave vector to compensate is lacking in the nonsuperconducting region.Interestingly,when the direction of polarization of light is changed,-φ_(0) to φ_(0) transition generates,which generalizes the concept of traditional 0–πtransition.Our findings provide a purely optical way to manipulate a phase-controllable Josephson device and guidelines for future experiments to confirm the presence of graphene-based φ_(0)Josephson junction. 展开更多
关键词 GRAPHENE circularly polarized light staggered sublattice potential φ_(0)Josephson junction
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