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Templated synthesis of transition metal phosphide electrocatalysts for oxygen and hydrogen evolution reactions 被引量:1
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作者 Rose Anne Acedera Alicia Theresse Dumlao +4 位作者 DJ Donn Matienzo Maricor Divinagracia Julie Anne del Rosario Paraggua Po-Ya Abel Chuang Joey Ocon 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期646-669,I0014,共25页
Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based catalysts... Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based catalysts.TMPs have been produced in various morphologies,including hollow and porous nanostructures,which are features deemed desirable for electrocatalytic materials.Templated synthesis routes are often responsible for such morphologies.This paper reviews the latest advances and existing challenges in the synthesis of TMP-based OER and HER catalysts through templated methods.A comprehensive review of the structure-property-performance of TMP-based HER and OER catalysts prepared using different templates is presented.The discussion proceeds according to application,first by HER and further divided among the types of templates used-from hard templates,sacrificial templates,and soft templates to the emerging dynamic hydrogen bubble template.OER catalysts are then reviewed and grouped according to their morphology.Finally,prospective research directions for the synthesis of hollow and porous TMP-based catalysts,such as improvements on both activity and stability of TMPs,design of environmentally benign templates and processes,and analysis of the reaction mechanism through advanced material characterization techniques and theoretical calculations,are suggested. 展开更多
关键词 OER HER Transition metal phosphide templated synthesis ELECTROCATALYSTS
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Road Traffic Monitoring from Aerial Images Using Template Matching and Invariant Features
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作者 Asifa Mehmood Qureshi Naif Al Mudawi +2 位作者 Mohammed Alonazi Samia Allaoua Chelloug Jeongmin Park 《Computers, Materials & Continua》 SCIE EI 2024年第3期3683-3701,共19页
Road traffic monitoring is an imperative topic widely discussed among researchers.Systems used to monitor traffic frequently rely on cameras mounted on bridges or roadsides.However,aerial images provide the flexibilit... Road traffic monitoring is an imperative topic widely discussed among researchers.Systems used to monitor traffic frequently rely on cameras mounted on bridges or roadsides.However,aerial images provide the flexibility to use mobile platforms to detect the location and motion of the vehicle over a larger area.To this end,different models have shown the ability to recognize and track vehicles.However,these methods are not mature enough to produce accurate results in complex road scenes.Therefore,this paper presents an algorithm that combines state-of-the-art techniques for identifying and tracking vehicles in conjunction with image bursts.The extracted frames were converted to grayscale,followed by the application of a georeferencing algorithm to embed coordinate information into the images.The masking technique eliminated irrelevant data and reduced the computational cost of the overall monitoring system.Next,Sobel edge detection combined with Canny edge detection and Hough line transform has been applied for noise reduction.After preprocessing,the blob detection algorithm helped detect the vehicles.Vehicles of varying sizes have been detected by implementing a dynamic thresholding scheme.Detection was done on the first image of every burst.Then,to track vehicles,the model of each vehicle was made to find its matches in the succeeding images using the template matching algorithm.To further improve the tracking accuracy by incorporating motion information,Scale Invariant Feature Transform(SIFT)features have been used to find the best possible match among multiple matches.An accuracy rate of 87%for detection and 80%accuracy for tracking in the A1 Motorway Netherland dataset has been achieved.For the Vehicle Aerial Imaging from Drone(VAID)dataset,an accuracy rate of 86%for detection and 78%accuracy for tracking has been achieved. 展开更多
关键词 Unmanned Aerial Vehicles(UAV) aerial images DATASET object detection object tracking data elimination template matching blob detection SIFT VAID
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A Joint Entity Relation Extraction Model Based on Relation Semantic Template Automatically Constructed
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作者 Wei Liu Meijuan Yin +1 位作者 Jialong Zhang Lunchong Cui 《Computers, Materials & Continua》 SCIE EI 2024年第1期975-997,共23页
The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of... The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of defining the semantic template of relation manually is particularly prominent in the extraction effect because it can obtain the deep semantic information of relation.However,this method has some problems,such as relying on expert experience and poor portability.Inspired by the rule-based entity relation extraction method,this paper proposes a joint entity relation extraction model based on a relation semantic template automatically constructed,which is abbreviated as RSTAC.This model refines the extraction rules of relation semantic templates from relation corpus through dependency parsing and realizes the automatic construction of relation semantic templates.Based on the relation semantic template,the process of relation classification and triplet extraction is constrained,and finally,the entity relation triplet is obtained.The experimental results on the three major Chinese datasets of DuIE,SanWen,and FinRE showthat the RSTAC model successfully obtains rich deep semantics of relation,improves the extraction effect of entity relation triples,and the F1 scores are increased by an average of 0.96% compared with classical joint extraction models such as CasRel,TPLinker,and RFBFN. 展开更多
关键词 Natural language processing deep learning information extraction relation extraction relation semantic template
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Online adaptive dwell scheduling based on dynamic template for PAR 被引量:2
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作者 TAN Qianqian CHENG Ting LI Xi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第5期1119-1129,共11页
An adaptive dwell scheduling algorithm for phased array radar(PAR)is proposed in this paper.The concept of online dynamic template is introduced,based on which a general pulse interleaving technique for PAR is put for... An adaptive dwell scheduling algorithm for phased array radar(PAR)is proposed in this paper.The concept of online dynamic template is introduced,based on which a general pulse interleaving technique for PAR is put forward.The pulse interleaving condition of the novel pulse interleaving is more intuitive and general.The traditional adaptive dwell scheduling algorithm combined with the general novel pulse interleaving technique results in the online adaptive dwell scheduling based on dynamic template for PAR is given.The proposed algorithm is suitable for radar tasks with multiple pulse repetition intervals(PRIs),which can be utilized in the actual radar system.For the purpose of further improving the scheduling efficiency,an efficient version is proposed.Simulation results demonstrate the effectiveness of the proposed algorithm and the efficient one.The proposed efficient algorithm can improve the time utilization ratio(TUR)by 9%,the hit value ratio(HVR)by 3.5%,and reduce the task drop ratio(TDR)by 6%in comparison with existing dwell scheduling algorithms considering pulse interleaving in PAR and the proposed efficient one. 展开更多
关键词 dynamic template dwell scheduling pulse interleaving
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Template synthesis of copper azide primary explosive through Cu2O@HKUST-1 core-shell composite prepared by “bottle around ship” method 被引量:1
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作者 Xu-wen Liu Yan Hu +4 位作者 Jia-heng Hu Jia-xin Su Cai-min Yang Ying-hua Ye Rui-qi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期99-111,共13页
Copper azide(CA), as a primary explosive with high energy density, has not been practically used so far because of its high electrostatic sensitivity. The Cu2O@HKUST-1 core-shell structure hybrid material was synthesi... Copper azide(CA), as a primary explosive with high energy density, has not been practically used so far because of its high electrostatic sensitivity. The Cu2O@HKUST-1 core-shell structure hybrid material was synthesized by the “bottle around ship” methodology in this research by regulating the dissolution rate of Cu2O and the generation rate of metal-organic framework(MOF) materials. Cu2O@HKUST-1 was carbonized to form a Cu O@porous carbon(CuO@PC) composite material. CuO@PC was synthesized into a copper azide(CA) @PC composite energetic material through a gas-solid phase in-situ azidation reaction.CA is encapsulated in PC framework, which acts as a nanoscale Faraday cage, and its excellent electrical conductivity prevents electrostatic charges from accumulating on the energetic material’s surface. The CA@PC composite energetic material has a CA content of 89.6%, and its electrostatic safety is nearly 30times that of pure CA(1.47 mJ compared to 0.05 mJ). CA@PC delivers an outstanding balance of safety and energy density compared to similar materials. 展开更多
关键词 Composite energetic materials Copper azide CARBONIZATION template method Core-shell composite Electrostatic safety
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Reactive template-derived interfacial engineering of CoP/CoO heterostructured porous nanotubes towards superior electrocatalytic hydrogen evolution 被引量:1
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作者 Qixing Zhou Ruoxu Sun +7 位作者 Yiping Ren Run Tian Jun Yang Huan Pang Kai Huang Xinlong Tian Lin Xu Yawen Tang 《Carbon Energy》 SCIE CAS CSCD 2023年第1期194-205,共12页
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut... The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future. 展开更多
关键词 HETEROJUNCTION hydrogen evolution reaction porous nanotubes reactive template
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Synthesis and Characterization of Hollow Strontium Carbonate Pompons by Composite Soft Template Method
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作者 LI Bibo DONG Xiufang +4 位作者 LI Yu SONG Jian XIE Wuxi ZHANG Wei LIU Yunfei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1434-1439,共6页
The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as templat... The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as template.The sampled particles were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption measurement,X-ray diffraction(XRD),Energy dispersive X-Ray spectroscopy(EDX),Fourier transform infrared spectroscopy(FTIR),Thermogravimetric analysis and differential scanning calorimetry(TGA-DSC),etc.It is shown that the assynthesized hollow strontium carbonate pompons with the size of about 2μm consist of flake-like particles under the optimal reaction conditions.The formation mechanism of hollow strontium carbonate pompons was preliminarily explored. 展开更多
关键词 strontium carbonate hollow structure pompons composite soft template method
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Efficient Scalable Template-Matching Technique for Ancient Brahmi Script Image
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作者 Sandeep Kaur Bharat Bhushan Sagar 《Computers, Materials & Continua》 SCIE EI 2023年第1期1541-1559,共19页
Analysis and recognition of ancient scripts is a challenging task as these scripts are inscribed on pillars,stones,or leaves.Optical recognition systems can help in preserving,sharing,and accelerate the study of the a... Analysis and recognition of ancient scripts is a challenging task as these scripts are inscribed on pillars,stones,or leaves.Optical recognition systems can help in preserving,sharing,and accelerate the study of the ancient scripts,but lack of standard dataset for such scripts is a major constraint.Although many scholars and researchers have captured and uploaded inscription images on various websites,manual searching,downloading and extraction of these images is tedious and error prone.Web search queries return a vast number of irrelevant results,and manually extracting images for a specific script is not scalable.This paper proposes a novelmultistage system to identify the specific set of script images from a large set of images downloaded from web sources.The proposed system combines the two most important pattern matching techniques-Scale Invariant Feature Transform(SIFT)and Template matching,in a sequential pipeline,and by using the key strengths of each technique,the system can discard irrelevant images while retaining a specific type of images. 展开更多
关键词 Brahmi script SIFT(scale-invariant feature transform) multi-scale template matching web scraping
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Impact of Laboratory Value Flowsheet in Electronic Health Record (EHR) Documentation Time
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作者 Isabel Rosado Pogozelski 《Open Journal of Nursing》 2024年第1期40-50,共11页
Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;... Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;and research that found that it is time consuming. The purpose of this quantitative retrospective before-after project was to measure the impact of using the laboratory value flowsheet within the EHR on documentation time. The research question was: “Does the use of a laboratory value flowsheet in the EHR impact documentation time by primary care providers (PCPs)?” The theoretical framework utilized in this project was the Donabedian Model. The population in this research was the two PCPs in a small primary care clinic in the northwest of Puerto Rico. The sample was composed of all the encounters during the months of October 2019 and December 2019. The data was obtained through data mining and analyzed using SPSS 27. The evaluative outcome of this project is that there is a decrease in documentation time after implementation of the use of the laboratory value flowsheet in the EHR. However, patients per day increase therefore having an impact on the number of patients seen per day/week/month. The implications for clinical practice include the use of templates to improve workflow and documentation as well as decreasing documentation time while also increasing the number of patients seen per day. . 展开更多
关键词 Electronic Health Record EHR Laboratory Results template Documentation Time
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Direct electrodeposition of ionic liquid-based template-free Sn Co alloy nanowires as an anode for Li-ion batteries 被引量:6
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作者 Le-ping Wang Gang Chen +3 位作者 Qi-xin Shen Guo-min Li Shi-you Guan Bing Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第9期1027-1034,共8页
Sn Co alloy nanowires were successfully electrodeposited from Sn Cl2-Co Cl2-1-ethyl-3-methylimidazolium chloride(EMIC) ionic liquid without a template. The nanowires were obtained from the molar ratio of 5:40:60 for S... Sn Co alloy nanowires were successfully electrodeposited from Sn Cl2-Co Cl2-1-ethyl-3-methylimidazolium chloride(EMIC) ionic liquid without a template. The nanowires were obtained from the molar ratio of 5:40:60 for Sn Cl2(25)Co Cl2(25)EMIC at-0.55 V and showed a minimum diameter of about 50 nm and lengths of over 20 μm. The as-fabricated SnCo nanowires were about 70 nm in diameter and featured a Sn/Co weight ratio of 3.85:1, when used as an anode for a Li-ion battery, they presented respective specific capacities of 687 and 678 m Ah·g^(-1) after the first charge and discharge cycle and maintained capacities of about 654 m Ah·g^(-1) after 60 cycles and 539 m Ah·g^(-1) after 80 cycles at a current density of 300 m A·g^(-1). Both the nanowire structure and presence of elemental Co helped buffer large volume changes in the Sn anode during charging and discharging to a certain extent, thereby improving the cycling performance of the Sn anode. 展开更多
关键词 SnCo alloy NANOWIRES template ELECTRODEPOSITION IONIC liquid
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Application of the Guiding Template Designed by Three-dimensional Printing Data for the Insertion of Sacroiliac Screws:a New Clinical Technique 被引量:5
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作者 Yi LIU Wu ZHOU +5 位作者 Tian XIA Jing LIU Bo-bin MI Liang-cong HU Zeng-wu SHAO Guo-hui LIU 《Current Medical Science》 SCIE CAS 2018年第6期1090-1095,共6页
This study is aimed to explore the clinical application of the guiding template designed by three-dimensional printing data for the insertion of sacroiliac screws.A retrospective study of 7 cases (from July 2016 to De... This study is aimed to explore the clinical application of the guiding template designed by three-dimensional printing data for the insertion of sacroiliac screws.A retrospective study of 7 cases (from July 2016 to December 2016),in which the guiding template printed by the three-dimensional printing technique was used for the insertion of sacroiliac screws of patients with posterior ring injuries of pelvis,was performed.Totally,4 males and 3 females were included in template group,aged from 38to 65years old (mean 50.86±8.90).Of them,5 had sacral fractures (3 with Denis type Ⅰ and 2 with type Ⅱ)and 2 the separation of sacroiliac joint.Guiding templates were firstly made by the three-dimensional printing technique based on the pre-operative CT data. Surgical operations for the stabilization of pelvic ring by applying the guiding templates were carried out.A group of 8 patients with sacroiliac injuries treated by percutaneous sacroiliac screws were analyzed as a control group retrospectively.The time of each screw insertion,volume of intra-operative blood loss,and the exposure to X ray were analyzed and the Matta's radiological criteria were used to evaluate the reduction quality.The Majeed score was used to evaluate postoperative living quality.The visual analogue scale (VAS)was applied at different time points to judge pain relief of coccydynia.All the 7 patients in the template group were closely followed up radiographically and clinically for 14 to 20 months,mean (16.57±2.44)months.Totally 9 sacroiliac screws for the S 1 and S2 vertebra were inserted in the 7 patients.The time length for each screw insertion ranged from 450 to 870 s,mean (690.56±135.68)s,and the number of times of exposure to X ray were 4 to 8,mean (5.78±1.20).The intra-operative blood loss ranged from 45to 120 mL,mean (75±23.32)mL.According to Matta's radiology criteria,the fracture and dislocation reduction were excellent in 6cases and good in 1.The pre-operative VAS score ranged from 5.2 to 8.1,mean (7.13±1.00).The average one-week/six-month post-operative VAS was (5.33±0.78)and (1.33±0.66),respectively (P<0.05 when compared with pre-operative VAS).The 12-month post-operative Majeed score ranged from 86 to 92,mean (90.29±2.21).The three-dimensional printed guiding template for sacroiliac screw insertion,which could significantly shorten the operation time,provide a satisfied outcome of the stabilization of the pelvic ring,and protect doctors and patients from X-ray exposure,might be a practical and valuable new clinical technique. 展开更多
关键词 SACROILIAC screws three-dimensional printing TECHNIQUE POSTERIOR PELVIC ring injury GUIDING template
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An enzyme-loaded reactor using metal-organic framework-templated polydopamine microcapsule 被引量:5
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作者 Jing Wang Yongqin Lv 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期317-325,共9页
Ultrathin polydopamine microcapsules with hierarchical structure and porosity were prepared for the immobilization of multienzymes using metal-organic framework(MOF) as the template.The multienzyme/MOF composite was f... Ultrathin polydopamine microcapsules with hierarchical structure and porosity were prepared for the immobilization of multienzymes using metal-organic framework(MOF) as the template.The multienzyme/MOF composite was first prepared using a "one-pot" co-precipitation approach via the coordination and self-assembly of zinc ions and 2-methylimidazole in the presence of enzymes.The obtained nanoparticles were then coated with polydopamine thin layer through the self-polymerization of dopamine under alkaline condition.The polydopamine microcapsules with an ultrathin shell thickness of ~48 nm were finally generated by removing the MOF template at acidic condition.Three enzymes were encapsulated in PDA microcapsules including carbonic anhydrase(CA),formate dehydrogenase(FateDH),and glutamate dehydrogenase(GDH).FateDH that catalyzed the main reaction of CO_(2) reduction to formic acid retained 94.7% activity of equivalent free FateDH.Compared with free multienzymes,the immobilized ones embedded in PDA microcapsules exhibited 4.5-times higher of formate production and high catalytic efficiency with a co-factor-based formate yield of 342%. 展开更多
关键词 BIOCATALYSIS ENZYME IMMOBILIZATION MICROCAPSULE Metal-organic framework template
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Preparation of silver nanoparticle via active template under ultrasonic 被引量:4
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作者 郑敏 王作山 朱亚伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2006年第6期1348-1352,共5页
A novel method was described for the production of silver nanoparticle by using nano-carbon as active template.Special ultrasonic condition was used to assure the active effect of the template and achieve an even and ... A novel method was described for the production of silver nanoparticle by using nano-carbon as active template.Special ultrasonic condition was used to assure the active effect of the template and achieve an even and stable micro-reactor system,therefore yield uniform silver nanoparticle without obvious agglomeration.By laser granularity instrument measurement,the silver nanoparticles show a mean diameter of 20.4 nm and narrow distribution between 18.7 nm and 23.0 nm according to the optimum technology.Regular spherical morphology can be observed by transmission electron microscopy(TEM).X-ray diffraction analysis indicates that Ag+ is deoxidized to form metal Ag during producing precursor,subsequent calcinations promote phase transformation from nonholonomic crystal to complete cubic crystal,which is consistent with the standard JCPDS card of silver.The results reveal that the nano-carbon in active template system not only exerts micro-reactor and steric stabilization effect,but also acts as reducing agent during the reaction. 展开更多
关键词 silver NANOPARTICLE ACTIVE template NANO-CARBON ULTRASONIC AGGLOMERATION
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SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS 被引量:6
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作者 Jie-bin Pang Kun-yuan Qiu Yen Wei Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China. Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, USA. 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期469-472,共4页
Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydrid... Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymer in the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template or pore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder X-ray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m(2)/g) and pore volumes (e.g. 0.6 cm(3)/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, pore volumes and pore diameters of the hybrid materials increase. 展开更多
关键词 mesoporous hybrid material poly(styrene-co-maleic anhydride)/silica citric acid nonsurfactant template sol-gel process
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A multiple template approach for robust tracking of fast motion target 被引量:6
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作者 SUN Jun HE Fa-zhi +1 位作者 CHEN Yi-lin CHEN Xiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第2期177-197,共21页
Target tracking is very important in computer vision and related areas. It is usually difficult to accurately track fast motion target with appearance variations. Sometimes the tracking algorithms fail for heavy appea... Target tracking is very important in computer vision and related areas. It is usually difficult to accurately track fast motion target with appearance variations. Sometimes the tracking algorithms fail for heavy appearance variations. A multiple template method to track fast motion target with appearance changes is presented under the framework of appearance model with Kalman filter. Firstly, we construct a multiple template appearance model, which includes both the original template and templates affinely transformed from original one. Generally speaking, appearance variations of fast motion target can be covered by affine transformation. Therefore, the affine tr templates match the target of appearance variations better than conventional models. Secondly, we present an improved Kalman filter for approx- imate estimating the motion trail of the target and a modified similarity evaluation function for exact matching. The estimation approach can reduce time complexity of the algorithm and keep accuracy in the meantime. Thirdly, we propose an adaptive scheme for updating template set to alleviate the drift problem. The scheme considers the following differences: the weight differences in two successive frames; different types of affine transformation applied to templates. Finally, experiments demonstrate that the proposed algorithm is robust to appearance varia- tion of fast motion target and achieves real-time performance on middle/low-range computing platform. 展开更多
关键词 Target tracking Fast motion target Multiple template match Kalman filter forecast.
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Optoelectronic characterisation of an individual ZnO nanowire in contact with a micro-grid template 被引量:5
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作者 姜威 高红 +4 位作者 徐玲玲 马佳宁 张锷 魏平 林家齐 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期416-419,共4页
Optoelectronic characterisation of an individual ZnO nanowire in contact with a micro-grid template has been studied. The low-cost micro-grid template made by photolithography is used to fabricate the ohmic contact me... Optoelectronic characterisation of an individual ZnO nanowire in contact with a micro-grid template has been studied. The low-cost micro-grid template made by photolithography is used to fabricate the ohmic contact metal electrodes. The current increases linearly with the bias, indicating good ohmic contacts between the nanowire and the electrodes. The resistivity of the ZnO nanowire is calculated to be 3.8 Ω·cm. We investigate the photoresponses of an individual ZnO nanowire under different light illumination using light emitting diodes (λ= 505 nm, 460 nm, 375 nm) as excitation sources in atmosphere. When individual ZnO nanowire is exposured to different light irradiation, we find that it is extremely sensitive to UV illumination; the conductance is much larger upon UV illumination than that in the dark at room temperature. This phenomenon may be related to the surface oxygen molecule adsorbtion, which indicates their potential application to the optoelectronic switching device. 展开更多
关键词 ZnO nanowire OPTOELECTRONIC micro-grid template
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Sweet spot prediction in tight sandstone reservoir based on well-bore rock physical simulation 被引量:4
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作者 Hai-ting Zhou De-yong Li +2 位作者 Xian-tai Liu Yu-shan Du Wei Gong 《Petroleum Science》 SCIE CAS CSCD 2019年第6期1285-1300,共16页
To establish the relationship among reservoir characteristics and rock physical parameters,we construct the well-bore rock physical models firstly,considering the influence factors,such as mineral composition,shale co... To establish the relationship among reservoir characteristics and rock physical parameters,we construct the well-bore rock physical models firstly,considering the influence factors,such as mineral composition,shale content,porosity,fluid type and saturation.Then with analyzing the change rules of elastic parameters along with the above influence factors and the cross-plots among elastic parameters,the sensitive elastic parameters of tight sandstone reservoir are determined,and the rock physics template of sweet spot is constructed to guide pre-stack seismic inversion.The results show that velocity ratio and Poisson impedance are the most sensitive elastic parameters to indicate the lithologic and gas-bearing properties of sweet spot in tight sandstone reservoir.The high-quality sweet spot is characterized by the lower velocity ratio and Poisson impedance.Finally,the actual seismic data are selected to predict the sweet spots in tight sandstone gas reservoirs,so as to verify the validity of the rock physical simulation results.The significant consistency between the relative logging curves and inversion results in different wells implies that the utilization of well-bore rock physical simulation can guide the prediction of sweet spot in tight sandstone gas reservoirs. 展开更多
关键词 Tight sandstone reservoir Sweet spot Sensitive elastic parameter well-bore rock physical simulation Rock physics template Pre-stack seismic inversion
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POROUS MEMBRANE TEMPLATED SYNTHESIS OF POLYMER PILLARED LAYER 被引量:4
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作者 杨振忠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第3期381-384,共4页
The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates tosynthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pore... The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates tosynthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pores, and thelayer on the template surfaces. Rigid cured epoxy resin, polystyrene and soft hydrogel were chosen to confirm themethodology. The pillars were in the form of either tubes or fibers, which were controlled by the alumina membrane pore surface wettability. The structural features were confirmed by scanning electron microscopy results. 展开更多
关键词 Anodic porous alumina membranes template synthesis Pillared layer POLYMERS
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Production of gasoline range hydrocarbons from methanol on hierarchical ZSM-5 and Zn/ZSM-5 catalyst prepared with soft second template 被引量:4
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作者 Xiaodong Wang Xiaoxia Gao +2 位作者 Mei Dong Hongbin Zhao Wei Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第4期490-496,共7页
Nano hierarchical mesoporous ZSM-5 catalysts were prepared with cationic dimethyldiallyl ammonium chloride acrylamide copolymer(PDDA) as a soft second template. Using ZSM-5 catalyst as a matrix,Zn/ZSM-5 catalysts we... Nano hierarchical mesoporous ZSM-5 catalysts were prepared with cationic dimethyldiallyl ammonium chloride acrylamide copolymer(PDDA) as a soft second template. Using ZSM-5 catalyst as a matrix,Zn/ZSM-5 catalysts were also obtained by the wet impregnation method. The effect of the PDDA amount and Zn loadings on the properties of the catalysts,including crystallinity,morphology,textural properties,acid nature and catalytic activity in MTG reaction,was investigated by XRD,FESEM,TEM,Nitrogen adsorption–desorption isotherms and NH3-TPD method,respectively. The MTG reaction was performed in a fixed bed reactor,and the result revealed that the nano hierarchical ZSM-5 catalyst prepared with a PDDA/Si molar ratio of 0.070 possesses longer stable phase of 70 h with a liquid hydrocarbon selectivity of 29.8%.Zn/ZSM-5 catalyst with a Zn/ZSM-5 ratio of 0.07 wt.% shows the highest liquid hydrocarbon selectivity,reaching 62.5%. 展开更多
关键词 Soft second template MTG reaction Nano hierarchical ZSM-5
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Fabrication of Large-area 3-D Ordered Silvercoated Colloidal Crystals and Macroporous Silver Films Using Polystyrene Templates 被引量:3
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作者 Wen Zhu Yuanyuan Wu +2 位作者 Chengyin Wang Ming Zhang Guanxiu Dong 《Nano-Micro Letters》 SCIE EI CAS 2013年第3期182-190,共9页
The highly ordered silver-coated colloidal crystals arrays and macroporous silver films were derived through an electrostatics-induced adsorption effect using polystyrene(PS) as templates. Carboxyl-modified PS microsp... The highly ordered silver-coated colloidal crystals arrays and macroporous silver films were derived through an electrostatics-induced adsorption effect using polystyrene(PS) as templates. Carboxyl-modified PS microspheres were prepared by emulsifier-free emulsion polymerization using methacrylic acid(MAA) as the functional monomer. PS microspheres were self-assembled into close packing colloidal crystals of facecentered cubic arrays to the substrate with vertical deposition method. These colloidal crystals were modified using dopamine(DA) to form poly-dopamine(PDA) during its oxidative polymerization. Through electrostatic interaction, the silver nanoparticles were deposited and adsorbed onto the surfaces of colloidal crystals templates by exposing [Ag(NH_3)_2]^+solution to infrared irradiation. Removal of the polymeric template by etching with methylbenzene solvent resulted in 3D ordered macroporous silver films. The structural and properties of the ordered silver-coated arrays and macroporous silver films were characterized by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD), UV-vis spectroscopy and surface-enhanced Raman spectroscopy(SERS). The results indicate that the prepared silver-coated arrays and macroporous silver films possess the features of ordered multilayer arrangement, uniformity and repeatability as well as an ideal SERS effect. 展开更多
关键词 Polystyrene colloidal crystal template DOPAMINE Silver-coated array Ordered macroporous film
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