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Enhanced hydrogen evolution in neutral media via proximity effect of Ru/RuO_(2)-TiO_(2) nanocatalysts 被引量:1
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作者 Yifan Yang Lixiong Xu +5 位作者 Chenyue Li Rongqian Ning Jun Ma Mengqin Yao Shuo Geng Fei Liu 《Journal of Materials Science & Technology》 2025年第9期173-181,共9页
Ru-based nanomaterials have been demonstrated to be highly active electrocatalysts for hydrogen evo-lution reaction(HER),yet weak water adsorption and splitting ability in neutral media thus it is rather difficult for... Ru-based nanomaterials have been demonstrated to be highly active electrocatalysts for hydrogen evo-lution reaction(HER),yet weak water adsorption and splitting ability in neutral media thus it is rather difficult for the intermediates to adsorb on the active site.Herein,we introduce a concept of the prox-imity effect,com prising adjacent Ru and RuO_(2) nanoparticles coupled on TiO_(2)(Ru/RuO_(2)-TiO_(2)),for the synergic promotion of water molecule adsorption and splitting,significantly enhancing HER electrocatal-ysis performance.The in-situ spectroscopy experiments and density function theory(DFT)simulations demonstrated that the proximity effect between the adjacent Ru nanoparticles and RuO_(2) nanoparticles can accelerate water adsorption and splitting.As a result,the as-made Ru/RuO_(2)-TiO_(2) only need overpo-tentials of 52.7,16.0,and 16.4 mV to achieve the current density of 10 mA cm-2 in neutral,acid,and alkaline media,respectively.The mass activity of Ru/RuO_(2)-TiO_(2) in neutral media is 320 and 117 times higher than that of commercial Ru/C and Pt/C at the overpotential of 100 mV,respectively.This work emphasizes the proximity effect for activation of reactants which can be extended to other electrocat-alytic reactions. 展开更多
关键词 Hydrogen evolution reaction Water activation proximity effect RUTHENIUM
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A proximity tagging strategy utilizing an activated aldehyde group as the active site
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作者 Mengfan Zhang Lingyan Liu +2 位作者 Peng Wei Wei Feng Tao Yi 《Chinese Chemical Letters》 2025年第4期605-610,共6页
Utilizing small molecules as markers for specific cells or organs within biosystems is a crucial approach for studying and regulating physiological processes. However, current tagging strategies, due to the presence o... Utilizing small molecules as markers for specific cells or organs within biosystems is a crucial approach for studying and regulating physiological processes. However, current tagging strategies, due to the presence of exposed highly reactive groups, suffer from drawbacks such as low tagging efficiency or insufficient spatial specificity, thereby diminishing their expected effectiveness. Consequently, there is a pressing need to develop a strategy capable of in situ labeling of active groups in response to cellular or in vivo stimuli, ensuring both high tagging efficiency and spatial specificity. In this work, we devised a strategy for releasing aldehyde groups activated by hypochlorous acid(HOCl). Compounds synthesized through this strategy can release the fiuorophore methylene blue(MB) and aldehyde-based compounds upon HOCl activation. Given high reactivity of the released aldehyde group, it can effectively interact with macromolecules in biological systems, facilitating tagging and enabling prolonged imaging. To validate this concept, we further incorporated a naphthalimide structure with stable light emission to create SW-110. SW-110 can specifically respond to in vitro and endogenous HOCl, when release MB, it also releases naphthalimide fiuorophore with highly reactive aldehyde group for tagging within cells. This strategy provides a simple but efficient strategy for proximity tagging in situ. 展开更多
关键词 ROS ALDEHYDE FLUORESCENCE Methylene blue proximity tagging strategy
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Proximity electronic effect of adjacent Ni Site enhances compatibility of hydrogenation and deoxygenation over Cu Site to boost nitrate electroreduction to ammonia
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作者 Xue-Feng Cheng Qing Liu +5 位作者 Qi-Meng Sun Huilong Dong Dong-Yun Chen Ying Zheng Qing-Feng Xu Jian-Mei Lu 《Chinese Journal of Catalysis》 2025年第3期285-298,共14页
Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon d... Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon dioxide emissions.However,high hydrogenation energy barrier for*NO intermediates and insufficient supply of active hydrogen cause slow hydrogenation process,and further result in low efficiency of nitrate conversion and ammonia synthesis.Herein,a series of tandem catalysts,one-dimensional coordination polymers(1D CCPs)with dual sites are synthesized and obtained 190.4 mg h^(-1)mgcat^(-1)ammonia production rate with Faradaic efficiency of 97.16%,outperforming to the most of recent reported catalysts.The catalytic performances are well-maintained even after a long-term stability test of 1200 h,laying the foundation for practical applications.Density functional theory results reveal that the stationary adsorbed*NO on Ni site induced proximity electronic effect could reduce the energy barrier for hydrogenation of*NO intermediates over Cu site.In addition,the Ni site in the dual sites 1D CCPs is conducive to generating active hydrogen,providing rich proton source to boost the hydrogenation of*NO,and further enhancing the compatibility of deoxygenation and hydrogenation process.Our work paves a new insight into the mechanism of NITRR process and will inspire more research interests in exploring the proximity electronic effect in catalytic process. 展开更多
关键词 ELECTROCATALYSIS Ammonia synthesis Nitrate reduction proximity electronic effect Dual sites
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Rationally designed an innovative proximity labeling near-infrared fluorogenic probe for imaging of peroxynitrite in acute lung injury
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作者 Dandan Tang Ningge Xu +4 位作者 Yuyang Fu Wei Peng Jinsheng Wu Heng Liu Fabiao Yu 《Chinese Chemical Letters》 2025年第5期498-503,共6页
Acute lung injury(ALI)is a serious clinical condition with a high mortality rate.Oxidative stress and inflammatory responses play pivotal roles in the pathogenesis of ALI.ONOO^(−)is a key mediator that exacerbates oxi... Acute lung injury(ALI)is a serious clinical condition with a high mortality rate.Oxidative stress and inflammatory responses play pivotal roles in the pathogenesis of ALI.ONOO^(−)is a key mediator that exacerbates oxidative damage and microvascular permeability in ALI.Accurate detection of ONOO^(−)would facilitate early diagnosis and intervention in ALI.Near-infrared fluorescence(NIRF)probes offer new solutions due to their sensitivity,depth of tissue penetration,and imaging capabilities.However,the developed ONOO^(−)fluorescent probes face problems such as interference from other reactive oxygen species and easy intracellular diffusion.To address these issues,we introduced an innovative self-immobilizing NIRF probe,DCI2F-OTf,which was capable of monitoring ONOO^(−)in vitro and in vivo.Importantly,leveraging the high reactivity of the methylene quinone(QM)intermediate,DCI2F-OTf was able to covalently label proteins in the presence of ONOO^(−),enabling in situ imaging.In mice models of ALI,DCI2F-OTf enabled real-time imaging of ONOO^(−)levels and found that ONOO^(−)was tightly correlated with the progression of ALI.Our findings demonstrated that DCI2F-OTf was a promising chemical tool for the detection of ONOO^(−),which could help to gain insight into the pathogenesis of ALI and monitor treatment efficacy. 展开更多
关键词 NEAR-INFRARED PEROXYNITRITE proximity labeling In situ bioimaging Acute lung injury
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Proximity defect inductive effect of atomic Ni-N_(3) sites by Te atoms doping for efficient oxygen reduction and hydrogen evolution
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作者 Min Li Xiuhui Zheng +3 位作者 Han Guo Xiang Feng Yunqi Liu Yuan Pan 《Journal of Energy Chemistry》 2025年第7期446-454,共9页
The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challen... The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challenging.Herein,N-doped carbon(N-C)anchored atomically dispersed Ni-N_(3)site with proximity defects(Ni-N_(3)D)induced by Te atoms doping is reported.Benefitting from the inductive effect of proximity defect,the Ni-N_(3)D/Te-N-C catalyst performs excellent ORR and HER performance in alkaline and acid condition.Both in situ characterization and theoretical calculation reveal that the existence of proximity defect effect is conducive to lower rate-determining-step energy barrier of ORR and HER,thus accelerating the multielectron reaction kinetics.This work paves a novel strategy for constructing highactivity bifunctional SACs by defect engineering for development of sustainable energy. 展开更多
关键词 proximity defect engineering Single atom catalyst Heteroatom doping Oxygen reduction reaction Hydrogen evolution reaction
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Proximity labeling proteomics with cilia-TurboID transgenic mice identified regulators of motile cilia function
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作者 Pan Wang Xiangnan Wu +9 位作者 Liqing Xiao Qingru Yu Yan Peng Mengting Yan Jun Tang Mingqiang Hu Hongtao Li Li Li Lingfei Luo Ming Ma 《Journal of Genetics and Genomics》 2025年第11期1413-1416,共4页
Cilia are indispensable for organ development and function,and their dysfunction causes a range of syndromic diseases known as ciliopathies,including obesity,cystic kidney disease,situs inversus,and male infertility(R... Cilia are indispensable for organ development and function,and their dysfunction causes a range of syndromic diseases known as ciliopathies,including obesity,cystic kidney disease,situs inversus,and male infertility(Reiter and Leroux,2017;Wallmeier et al.,2020).To date,over 180 ciliopathy-associated genes have been identified(Reiter and Leroux,2017),yet the underlying mechanisms remain poorly understood. 展开更多
关键词 PROTEOMICS proximity labeling syndromic diseases obesitycystic kidney diseasesitus male infertility reiter REGULATORS cilia turboid transgenic mice organ development
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Safety and oncologic outcomes of open versus minimally invasive distal pancreatectomy for resectable pancreatic body and tail cancer
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作者 Hajime Imamura Tomohiko Adachi +5 位作者 Ayaka Kinoshita Takashi Hamada Hajime Matsushima Takanobu Hara Akihiko Soyama Susumu Eguchi 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期83-90,共8页
Background:Minimally invasive distal pancreatectomy(MIDP)is increasingly being used,although its oncologic safety for pancreatic ductal adenocarcinoma(PDAC)remains controversial.In Japan,MIDP for PDAC has limited endo... Background:Minimally invasive distal pancreatectomy(MIDP)is increasingly being used,although its oncologic safety for pancreatic ductal adenocarcinoma(PDAC)remains controversial.In Japan,MIDP for PDAC has limited endorsement due to insufficient data.This study aimed to compare the perioperative and long-term outcomes of open distal pancreatectomy(ODP)and MIDP for PDAC.Methods:We retrospectively analyzed patients with resectable pancreatic body and tail cancer treated with ODP or MIDP(laparoscopic or robotic)between January 2007 and July 2022.The surgical procedures(ODP and MIDP)were compared and the patient characteristics,perioperative outcomes,and long-term outcomes were analyzed.We also compared the outcomes of patients with neoadjuvant chemotherapy(NAC)and without NAC.Results:A total of 72 distal pancreatectomies were performed(37 ODPs and 35 MIDPs).In the upfront group,MIDP resulted in significantly less blood loss than ODP(P<0.01),despite similar operative time.There was no statistically significant difference in the 2-year recurrence-free survival(RFS)rates between ODP and MIDP(39.7%vs.57.8%,P=0.60)or in the overall survival(OS)rates(66.7%vs.74.1%,P=0.43).Similarly,in the NAC group,MIDP resulted in significantly less blood loss than ODP(P=0.01);ODP and MIDP had similar 2-year RFS rates(41.7%and 60.0%,P=0.75)and OS rates(50.0%and 70.0%,P=0.36).The interval from surgery to adjuvant chemotherapy initiation did not significantly differ between the ODP and MIDP subgroups in both the upfront group(P=0.13)and the NAC group(P=0.14).The incidence of recurrence was 64.8%for ODP and 42.8%for MIDP(P=0.06).Both procedures showed similar distributions of local and distant recurrence.Conclusions:MIDP caused less blood loss and had similar oncologic safety compared with ODP.MIDP could become a feasible,minimally invasive option with sufficient oncologic safety for pancreatic body and tail cancers. 展开更多
关键词 Pancreatic body cancer Pancreatic tail cancer Minimally invasive pancreatectomy Laparoscopic distal pancreatectomy Robotic distal pancreatectomy Oncologic safety
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Defining and predicting textbook outcomes in laparoscopic distal pancreatectomy
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作者 Xiao-Rui Huang Deng-Sheng Zhu +6 位作者 Xin-Yi Guo Jing-Zhao Zhang Zhen Zhang Huan Zheng Tong Guo Ya-Hong Yu Zhi-Wei Zhang 《World Journal of Gastroenterology》 2026年第1期139-150,共12页
BACKGROUND Laparoscopic distal pancreatectomy(LDP)has emerged as the preferred approach for both benign and malignant lesions located in the pancreatic body and tail.Nevertheless,a notable deficiency persists in the a... BACKGROUND Laparoscopic distal pancreatectomy(LDP)has emerged as the preferred approach for both benign and malignant lesions located in the pancreatic body and tail.Nevertheless,a notable deficiency persists in the absence of a standardized,procedure-specific metric for evaluating and comparing surgical quality.A composite measure termed“textbook outcome(TO)”,which encompasses key short-term endpoints,has been validated in laparoscopic pancreatoduodenectomy but has not yet been established in dedicated LDP cohorts.The definition and prediction of TO in this context could aid in facilitating cross-institutional benchmarking and fostering advancements in quality improvement.AIM To establish procedure-specific criteria for TO and identify independent predictors of TO failure in patients undergoing LDP.METHODS Consecutive patients who underwent LDP at a single high-volume pancreatic center between January 2015 and August 2022 were retrospectively analyzed.TO was defined as the absence of clinically relevant postoperative pancreatic fistula(grade B/C),post-pancreatectomy hemorrhage(grade B/C),severe complications(Clavien-Dindo≥III),readmission within 30 days,and in-hospital or 30-day mortality.Multivariable logistic regression was employed to identify independent predictors of TO failure,and a nomogram was constructed and internally validated.RESULTS Among 405 eligible patients,286(70.6%)attained TO.Multivariable analysis revealed that female sex[odds ratio(OR)=0.62,95%confidence interval(CI):0.39-0.99]conferred a protective effect,while preoperative endoscopic ultrasound-guided fine-needle aspiration(OR=2.66,95%CI:1.05-6.73),pancreatic portal hypertension(OR=2.81,95%CI:1.06-7.45),and cystic-solid(OR=2.51,95%CI:1.34-4.69)or solid lesions(OR=1.91,95%CI:1.06-3.44)were independently associated with TO failure(all P<0.05).The derived nomogram exhibited modest discrimination and calibration when assessed in both the training and validation datasets.CONCLUSION The proposed LDP-specific definition of TO is feasible and discriminative,and the developed nomogram provides an objective tool for individualized risk assessment. 展开更多
关键词 Laparoscopic distal pancreatectomy Textbook outcome PREDICTORS Risk prediction model NOMOGRAM
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A New Method to Retrieve Proximity Effect Parameters in Electron-Beam Lithography 被引量:2
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作者 康晓辉 李志刚 +2 位作者 刘明 谢常青 陈宝钦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第3期455-459,共5页
A new method for determining proximity parameters α,β ,and η in electron beam lithography is introduced on the assumption that the point exposure spread function is composed of two Gaussians.A single line i... A new method for determining proximity parameters α,β ,and η in electron beam lithography is introduced on the assumption that the point exposure spread function is composed of two Gaussians.A single line is used as test pattern to determine proximity effect parameters and the normalization approach is adopted in experimental data transaction in order to eliminate the need of measuring exposure clearing dose of the resist.Furthermore,the parameters acquired by this method are successfully used for proximity effect correction in electron beam lithography on the same experimental conditions. 展开更多
关键词 electron beam lithography proximity effect electron-beam proximity correction
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Important Works About Rules in Rules-Based Optical Proximity Correction 被引量:2
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作者 石蕊 蔡懿慈 +2 位作者 洪先龙 吴为民 杨长旗 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期701-706,共6页
Considering the efficiency and veracity of rules based optical proximity correction (OPC),the importance of rules in rules based OPC is pointed out.And how to select,to construct and to apply more concise and practi... Considering the efficiency and veracity of rules based optical proximity correction (OPC),the importance of rules in rules based OPC is pointed out.And how to select,to construct and to apply more concise and practical rules base is disscussed.Based on those ideas,four primary rules are suggested.Some data resulted in rules base are shown in table.The patterns on wafer are clearly improved by applying these rules to correct mask.OPCL,the automatic construction of the rules base is an important part of the whole rules based OPC system. 展开更多
关键词 optical lithography optical proximity correction rules base
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仅根据Proximity数据构建向量空间模型的方法 被引量:1
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作者 徐硕 乔晓东 +1 位作者 朱礼军 郭怀恩 《情报学报》 CSSCI 北大核心 2011年第11期1163-1170,共8页
在实际应用中,许多研究对象都是抽象的,难以用某种特征向量的形式表示,这使得许多成熟的数据挖掘和机器学习方法难以被采用。不过,通常可将其转化成一个Proximity数据矩阵,使得矩阵中的元素表示两个对象间某种“比较”关系。针对... 在实际应用中,许多研究对象都是抽象的,难以用某种特征向量的形式表示,这使得许多成熟的数据挖掘和机器学习方法难以被采用。不过,通常可将其转化成一个Proximity数据矩阵,使得矩阵中的元素表示两个对象间某种“比较”关系。针对该问题,本文提出仅根据Proximity数据矩阵利用多维尺度分析法(MDS)将研究对象进行向量化表示,即构建了一种向量空间模型。最后,对汉语科技词系统中的词语进行了聚类分析,结果表明,向量空间模型构建后再聚类的结果明显优于直接针对Proximity数据进行聚类分析的结果,从而验证了该方法的可行性和有效性。 展开更多
关键词 多维尺度法 proximity数据 向量空间模型 汉语科技词系统 聚类分析
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Detailed Routing Algorithm with Optical Proximity Effects Constraint 被引量:1
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作者 周强 蔡懿慈 +1 位作者 张为 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第2期189-195,共7页
We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential... We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential routing. The routing algorithm is based on constructed force directed Steiner tree routing to enhance routing efficien- cy. Experimental results on industrial benchmark circuits show that the presented routing algorithm can obtain much improvement considering optical effects short runtime. 展开更多
关键词 optical proximity effect detailed routing Steiner tree YIELD
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Modeling Technology in Finite Element Analysis of Electrostatic Proximity Fuze Problem 被引量:2
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作者 李银林 施聚生 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期286-290,共5页
In order to analyze the electrostatic field concerned with electrostatic proximity fuze problem using the available finite analysis software package, the technology to model the problem with a scale reduction object a... In order to analyze the electrostatic field concerned with electrostatic proximity fuze problem using the available finite analysis software package, the technology to model the problem with a scale reduction object and boundary was presented. The boundary is determined by the maximum distance the sensor can detect. The object model is obtained by multiplying the terms in Poisson's equation with a scale reduction factor and the real value can be reconstructed with the same reverse process after software calculation. Using the finite element analysis program, the simulation value is close to the theoretical value with a little error. The boundary determination and scale reduction method is suitable to modeling the irregular electrostatic field around air targets, such as airplane, missile and so on, which is based on commonly used personal computer (PC). The technology reduces the calculation and storage cost greatly. 展开更多
关键词 electrostatic proximity fuze finite element analysis boundary condition scale reduction method
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一种CCSDS Proximity-1协议下全双工/半双工及单工的融合实现方法 被引量:4
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作者 田嘉 王伟 史平彦 《微电子学与计算机》 北大核心 2020年第6期66-69,共4页
针对深空探测任务中对产品小型化及低功耗的需求,各功能间的融合及模块的复用成为深空探测类产品设计中不可或缺的一环.本文提出了一种CCSDS Proximity-1协议下全双工/半双工及单工的融合实现方法,该方法通过将全双工模式、半双工模式... 针对深空探测任务中对产品小型化及低功耗的需求,各功能间的融合及模块的复用成为深空探测类产品设计中不可或缺的一环.本文提出了一种CCSDS Proximity-1协议下全双工/半双工及单工的融合实现方法,该方法通过将全双工模式、半双工模式及单工模式中的流式处理部分及特定功能部分从主框架中剥离,并进行融合设计,形成通用的VHDL结构;将其余调度控制部分集成在FPGA中的MicroBlaze结构中.通用的VHDL结构意味着资源配置最优,而MicroBlaze结构因其灵活性,可实现对不同模式的灵活切换.本方法将应用到下一代火星探测临近空间链路收发信机中,通过采用仅有1片V5的开发板,实现结果表明,CCSDS Proximity-1协议下的全双工、半双工及单工功能性能正常,且资源的消耗量仅为5%ALMs,6%DSP和8%RAM. 展开更多
关键词 CCSDS proximity-1协议 融合设计
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基于CCSDS Proximity-1协议的动态变帧长策略研究 被引量:4
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作者 任放 赵和平 陈曦 《航天器工程》 2013年第4期72-76,共5页
为提高邻近航天器之间的通信效率,研究了Proximity-1协议与传统链路层协议的最大区别——"通信互动"功能。对航天器之间通信过程中的动态变帧长策略进行了分析,给出了不同信道环境下的最佳帧长取值,并通过实时选择最佳帧长实... 为提高邻近航天器之间的通信效率,研究了Proximity-1协议与传统链路层协议的最大区别——"通信互动"功能。对航天器之间通信过程中的动态变帧长策略进行了分析,给出了不同信道环境下的最佳帧长取值,并通过实时选择最佳帧长实现了动态变帧长策略方案。利用仿真手段验证了动态变帧长策略对通信效率的改善性能。仿真结果表明,吞吐量效率最多可提高80%,证明文章提出的动态变帧长策略能在很大程度上提高通信效率。 展开更多
关键词 空间通信 空间数据系统 邻近空间链路 动态变帧长
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Fabrication of Sub-20nm Metal Nanogaps from Nanoconnections by the Extended Proximity Effect
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作者 孙艳 陈鑫 戴宁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1666-1669,共4页
We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography (EBL). The proximity effect is extended to develop a flexible and practical method fo... We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography (EBL). The proximity effect is extended to develop a flexible and practical method for preparing metal (e. g. Au or Ag) nanogaps and arrays in combination with a transfer process (e. g., deposition/lift-off). Different from the direct gap-writing process,the nanogap precursor structures (nanoconnections) were designed by GDSII software and then written by electron beam. Following a deposition and lift-off process, the metal nanogaps were obtained and the nanogap size can be lowered to -10nm by controlling the exposure dose in EBL. 展开更多
关键词 metal nanogap nanofabrication proximity effect electron beam lithography
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华沙圈上连续映射的distality与等度连续性
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作者 牛应轩 《大学数学》 2010年第5期86-89,共4页
设W为华沙圈,f:W→W为连续映射.本文得到了f为distal的一个刻画并且讨论了f的distality与等度连续性的关系.证明了:(i)f是distal的当且仅当f为恒等映射.(ii)如果f为满射,则f是distal的当且仅当f为等度连续的.
关键词 华沙圈 不动点集 distal 等度连续
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CCSDS Proximity-1及其在编队飞行小卫星群中的应用 被引量:2
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作者 王世练 张尔扬 《遥测遥控》 2003年第3期10-14,共5页
讨论近距离空间链路协议 Proximity- 1的层次结构和传输帧 Version- 3构成 ,分析包括 CCSDS标准包和用户自定义数据的数据业务及定时业务。针对编队飞行小卫星群的星间数据交换和自主测控 ,对 Proximity-
关键词 CCSDSproximity-1 编队飞行卫星群 星间链路
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China's regional transport dominance: Density, proximity, and accessibility 被引量:63
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作者 JIN Fengjun WANG Chengjin LI Xiuwei WANG Jiao'e 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期295-309,共15页
Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: qua... Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects: quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal: (1) Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. (2) Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level. 展开更多
关键词 transport dominance DENSITY proximity ACCESSIBILITY China
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伪补格上半Proximity结构的精粗半序 被引量:1
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作者 熊华平 《上饶师范学院学报》 2001年第3期1-7,共7页
笔者的论文“Proximity代数的一种合理定义”对经典拓朴中的Proximity空间论基础进行了合理的推广 ,在一般伪补格上建立了一种较为合理的Proximity结构以形成“(半 )Proximity代数” ,本文进一步讨论一个给定的伪补格L上一切半Proximit... 笔者的论文“Proximity代数的一种合理定义”对经典拓朴中的Proximity空间论基础进行了合理的推广 ,在一般伪补格上建立了一种较为合理的Proximity结构以形成“(半 )Proximity代数” ,本文进一步讨论一个给定的伪补格L上一切半Proximity结构组成的集合sp(L)和一切Proximity结构组成的集合p(L)的性质。 展开更多
关键词 proximity代数 伪补格 伪补同态 STONE代数 proximity同态 proximity结构 精粗半序
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