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Vapor-phase postsynthetic amination of hypercrosslinked polymers for efficient iodine capture 被引量:1
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作者 Pengcheng Su Shizheng Chen +3 位作者 Zhihong Yang Ningning Zhong Chenzi Jiang Wanbin Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第9期320-325,共6页
Hypercrosslinked polymers(HCPs)with large surface areas,high intrinsic porosities and low production costs may be available platforms for iodine capture.However,the lack of iodine-philicity binding sites limits their ... Hypercrosslinked polymers(HCPs)with large surface areas,high intrinsic porosities and low production costs may be available platforms for iodine capture.However,the lack of iodine-philicity binding sites limits their adsorption capacity.Here we use vapor-phase postsynthetic amination strategy to introduce electron-donating amino groups into the prefabricated HCPs for enhancing their iodine capture performance.Through simple vapor-phase exposure,the halogen-containing HCPs can be grafted by amines through nucleophilic substitution toward chloro groups.Combining with the abundant amino groups and high porosities,the amino-functionalized porous polymers show substantially increased iodine adsorption capacity,about 221%as that of original one,accompanied by excellent recyclability.Mechanism investigations reveal the key roles of the electron-donor amino groups andπ-conjugated benzene rings along with structure characteristics of porous polymer frameworks in iodine capture.Moreover,this vapor-phase amination strategy shows good generality and can be extended to various amines,e.g.,ethylenediamine,1,3-diaminopropane and diethylenetriamine.Our work proves that this simple vapor-phase postsynthetic functionalization strategy may be applied in other porous polymers with wide application prospects in adsorption,separation and storage. 展开更多
关键词 Porous polymers Postsynthetic amination Hypercrosslinked polymers vapor-phase grafting Iodine capture
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Synthesis of 4-Phenylphthalonitrile by Vapor-Phase Catalytic Ammoxidation of Intermediate 4-Phenyl-<i>o</i>-Tolunitrile: Reaction Kinetics 被引量:3
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作者 G. A. Bagirzade D. B. Tagiyev M. R. Manafov 《Modern Research in Catalysis》 2014年第1期6-11,共6页
Kinetic regularities of 4-phenyl-o-tolunitrile ammoxidation on V-Sb-Bi-Zr/γ-Al2O3 oxide catalyst in the temperature interval 633 - 673 K have been studied. It has been established that rates of conversion of 4-phenyl... Kinetic regularities of 4-phenyl-o-tolunitrile ammoxidation on V-Sb-Bi-Zr/γ-Al2O3 oxide catalyst in the temperature interval 633 - 673 K have been studied. It has been established that rates of conversion of 4-phenyl-o-tolu- nitrile into the aimed 4-phenylphthalonitrile and CO2 are described by half-order equation on concentration of substratum and to be independent of the oxygen and ammonia partial pressures. It has been revealed that formation of 4-phenylphthalimide from byproducts is due to hydrolysis of 4-phenylphthalonitrile;carbon dioxide is produced by oxidation of 4-phenyl-o-tolunitrile and decarboxylation of 4-phenylphthalimide, and 4-phenylben- zonitrile is produced from 4-phenyl-o-tolunitrile and 4-phenylphthalimide. 展开更多
关键词 CATALYTIC AMMOXIDATION Partial Pressures 4-Phenylphthalimide vapor-phase Electron-Donorship Kinetic Measurements
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Vapor-Phase Transport Synthesis of MnSAPO-34 and Its Catalytic Properties 被引量:1
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作者 Shao Hui Chen Xia +2 位作者 Wang Binbin Zhong Jing Yang Chao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第3期68-74,共7页
MnSAPO-34 molecular sieves were synthesized by vapor-phase transport (VPT) method using triethylamine (Et3N) as a structure directing agent (SDA), and were characterized by XRD, BET, SEM, UV-Vis, FT-IR, and TG a... MnSAPO-34 molecular sieves were synthesized by vapor-phase transport (VPT) method using triethylamine (Et3N) as a structure directing agent (SDA), and were characterized by XRD, BET, SEM, UV-Vis, FT-IR, and TG analy- ses. The influence of the zeolite crystallization conditions and the dry-gel composition were investigated. The results showed that the synthesis conditions had an effect on the crystalline phase. Pure MnSAPO-34 had been obtained when it was crystallized at 140 C for 18 hours. The ratio of MnO/A1203 in the starting gel ranging from 0.1 to 0.2 resulted in pure MnSAPO-34 with a CHA topology. Beyond this scope, MnSAPO-5 with an AFI topology structure was obtained as an impurity substance. UV-Vis spectroscopy and FT-IR spectroscopy study indicated that manganese was incorporated into the framework of the molecular sieve. The catalytic performance of MnSAPO-34 molecular sieve was tested by ketalization reaction of l, 2-propanediol with cyclohexanone. High yield of cyclohexanone-1, 2-propanediol ketal was obtained. 展开更多
关键词 MnSAPO-34 vapor-phase transport (VPT) KETALIZATION
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Expired drugs as vapor-phase corrosion inhibitors of copper in simulated marine atmospheric environment
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作者 WANG Xin-wei ZHANG Tian-long +4 位作者 LI Yan-tao YANG Li-hui XU Wei-chen DISNA Ratnasekera HAN Tao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3570-3582,共13页
Urea,paracetamol and glutamine(based on the expired drugs)were selected as vapor-phase corrosion inhibitors(VCIs)to study their corrosion protection effect on red copper in simulated marine atmospheric environment by ... Urea,paracetamol and glutamine(based on the expired drugs)were selected as vapor-phase corrosion inhibitors(VCIs)to study their corrosion protection effect on red copper in simulated marine atmospheric environment by using weight loss,electrochemical measurement techniques(specially designed electrochemical testing device for simulating marine atmospheric environments)and surface morphology characterization analysis(SEM/EDS,XRD,RAMAN,XPS).Weight loss results show that the three corrosion inhibitors have good corrosion inhibition effect on red copper,and the corrosion inhibition efficiency in the order of glutamine(83.62%)>urea(68.46%)>paracetamol(61.47%).Surface morphology characterization analysis provides evidence of adsorption of corrosion inhibitors molecules on the red copper surface,thus forming a protective film that blocked the red copper surface from the aggressive chloride ion attack. 展开更多
关键词 marine corrosion and protection vapor-phase corrosion inhibitor(VCI) COPPER expired drugs marine atmospheric environment
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Vapor-phase Nitration of Benzene to Nitrobenzene over Supported Sulfuric Acid Catalyst
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作者 Jing Lin CHEN Wei Guo CHENG +2 位作者 Hong Feng LIU Qing Song LIN Lian Hai LU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期311-314,共4页
Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%)... Vapor-phase nitration of benzene over solid acid catalyst is expected to be a clean process with no sulfuric acid waste. We investigated this process over solid acidic catalysts utilizing diluted nitric acid (60-70%) as nitrating agent, and found that supported sulfuric acid catalyst exhibited a very high catalytic activity. Under the conditions of reaction temperature 160-170℃, space velocity (SV) 1200 h-1, the yield and the space-time yield (STY) of nitrobenzene (NB) based on HNO3 were more than 98% and 0.75 kg穔gcat-1穐-1 over 10% H2SO4/SiO2 (by weight) catalyst respectively. 展开更多
关键词 Nitration (vapor-phase) sulfuric acid (supported catalyst) NITROBENZENE
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Silicalite-1 zeolite nanosheets with rich H-bonded silanols for boosting vapor-phase Beckmann rearrangement:One-pot synthesis and theoretical investigation
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作者 Tianming Zai Wei Chen +10 位作者 Jiamin Yuan Ye Ma Qinming Wu Xianfeng Yi Zhiqiang Liu Xiangju Meng Weiliao Liu Na Sheng Han Wang Anmin Zheng Feng-Shou Xiao 《Chinese Journal of Catalysis》 CSCD 2024年第12期82-90,共9页
Design and preparation of highly efficient zeolite catalysts for gas-phase Beckmann rearrangement of cyclohexanone oxime to caprolactam are attractive but still challenging.Herein,we show a one-pot synthesis of silica... Design and preparation of highly efficient zeolite catalysts for gas-phase Beckmann rearrangement of cyclohexanone oxime to caprolactam are attractive but still challenging.Herein,we show a one-pot synthesis of silicalite-1 zeolite nanosheets with rich H-bonded silanols.The key to this success is the use of urea in the synthetic system.Catalytic tests of cyclohexanone oxime gas-phase Beckmann rearrangement show that the silicalite-1 zeolite nanosheets with H-bonded silanols exhibit higher selectivity for caprolactam and longer reaction lifetime than those of the conventional silicalite-1 zeolite.Theoretical simulations reveal that the ammonium decomposed by urea is a critical additive for the formation of H-bond silanols.Obviously,one-pot synthesis of silicalite-1 zeolite nanosheets with rich H-bonded silanols plus excellent catalytic performance in the Beckmann rearrangement offer a new opportunity for development of highly efficient zeolites for catalytic applications in the future. 展开更多
关键词 Silicalite-1 zeolite nanosheets Rich H-bonded silanols One-pot synthesis vapor-phase Beckmann rearrangement Theoretical investigation
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Preparation of nanometer δ- and β-bismuth trioxide by vacuum vapor-phase oxidation 被引量:3
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作者 胡汉祥 丘克强 徐国富 《中国有色金属学会会刊:英文版》 CSCD 2006年第1期173-177,共5页
A stable δ- and β-bismuth trioxide was prepared at room temperature by vacuum vapor-phase oxidation. The average crystal size of products was 14.6 nm (by XRD), the d(0.5) value was in the range from 62 nm to 69 nm, ... A stable δ- and β-bismuth trioxide was prepared at room temperature by vacuum vapor-phase oxidation. The average crystal size of products was 14.6 nm (by XRD), the d(0.5) value was in the range from 62 nm to 69 nm, and geometric standard deviation(GSD) was from 1.42 to 1.64. The results show that δ-Bi2O3 is formed when quenching rates is rapid and β-Bi2O3 is formed when it is slow. The size of grains increases with rising reaction temperature, flow rate of carrier gas, residual pressure of system and longer growing time of grains. 展开更多
关键词 三氧化铋 真空气相氧化 纳米粒子 XRD 生长周期
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Lanthanum-Promoted Nickel Catalyst for Vapor-Phase Methanol Carbonylation
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作者 LI Fengbo, ZOU Jin, YUAN Guoqing (Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080, China) 《催化学报》 SCIE CAS CSCD 北大核心 2003年第4期239-240,共2页
关键词 Ni-La催化剂 催化反应 镍镧催化剂 甲醇 气相碳基化反应
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Compositional engineering nanoparticles and microwave absorption tuning of C-coated high-entropy alloy nanoparticles via vapor-phase synthesis
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作者 Sibt ul Hassan Sana Zafar +4 位作者 Lizhen Hou Tauqeer Haidar Qamar Yang Yang Daitao Kuang Shiliang Wang 《Science China Materials》 2025年第6期2056-2070,共15页
The tunable dielectric and magnetic properties of high entropy alloy(HEA)nanoparticles have attracted considerable interest in realizing optimal impedance matching and microwave absorption performance.However,the comp... The tunable dielectric and magnetic properties of high entropy alloy(HEA)nanoparticles have attracted considerable interest in realizing optimal impedance matching and microwave absorption performance.However,the compositional engineering of HEA nanoparticles in regulating their dielectric-magnetic balance to achieve high-performance microwave absorption remains challenging.Herein,a vaporphase synthesis method is employed to prepare C-coated CoNiFeCuCr_(x)HEA nanoparticles with tunable Cr content.The prepared HEA nanoparticles,with a size of less than 10 nm,exhibited typical soft ferromagnetic characteristics.In conjunction with the additional contributions of interfacial polarization,graphitization of the C-shell,and tunable Cr content to the regulation of electromagnetic parameters,the C-coated CoNiFeCuCr_(0.5) nanoparticles exhibit a minimum reflection loss(RL_(min))of−63.9 dB and an effective absorption bandwidth(EAB)of 5.52 GHz,with an optimal thickness of 2.1 mm.Moreover,by employing a gradient three-layer architectural design,the EAB can be further extended to 12.22 GHz.Simultaneously,the simulated radar cross-section(RCS)results highlight its exceptional radar stealth performance,with RCS values remaining below−20 dBm^(2) across a wide angular range of−85°to 85°.This study offers valuable perspectives on designing high-performance HEA-based electromagnetic wave absorbing materials,achieving outstanding microwave absorption and radar stealth capabilities through careful compositional engineering. 展开更多
关键词 high entropy alloy nanoparticles vapor-phase synthesis microwave absorption interfacial polarization radar cross-section
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Vapor-phase hydrothermal growth of single crystalline NiS2 nanostructure film on carbon fiber cloth for electrocatalytic oxidation of alcohols to ketones and simultaneous H2 evolution 被引量:5
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《Nano Research》 SCIE EI CAS CSCD 2018年第2期1004-1017,共14页
Electrocatalytic synthesis of value-added chemicals is attracting significant research attention owing to its mild reaction conditions, environmental benignity, and potentially scalable application to organic syntheti... Electrocatalytic synthesis of value-added chemicals is attracting significant research attention owing to its mild reaction conditions, environmental benignity, and potentially scalable application to organic synthetic chemistry. Herein, we report the preparation of a single-crystalline NiS2 nanostructure film of N 50 nm thickness grown directly on a carbon fiber doth (NiSJCFC) by a facile vapor-phase hydrothermal (VPH) method. NiSJCFC as an electrocatalyst exhibits activity for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in alkaline media. Furthermore, a series of alcohols (2-propanol, 2-butanol, 2-pentanol, and cyclohexanol) were electrocatalytically converted to the corresponding ketones with high selectivity, efficienc and durability using the NiSJCFC electrode in alkaline media. In the presence of 0.45 M alcohol, a remarkably decreased overpotential (- 150 mV, vs. RHE) at the NiS2/CFC anode compared with that for water oxidation to generate O2, i.e., the OER, in alkaline media leads to significantly improved H2 generation. For instance, the H2 generation rate in the presence of 0.45 M 2-propanol is almost 1.2-times of that obtained for pure water splitting, but in a system that employs an applied voltage at least 280 mV lower than that required for water splitting to achieve the same current density (20 mA-crn-2). Thus, our results demonstrate the applicability of our bifunctional non-precious-metal electrocatalyst for organic synthesis and simultaneous H2 production. 展开更多
关键词 vapor-phase hydrothermal single-crystalline NiS2 film carbon fiber cloth electrocatalytic oxidationof alcohols to ketones H2 generation
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Vapor-phase growth of high-quality wafer-scale two-dimensional materials 被引量:9
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作者 Xin Tong Keli Liu +1 位作者 Mengqi Zeng Lei Fu 《InfoMat》 SCIE CAS 2019年第4期460-478,共19页
Emerging two-dimensional(2D)materials have stimulated tremendous scientific and industrial interests due to their diverse and tunable physical,chemical,and mechanical properties.The scalable production of high-quality... Emerging two-dimensional(2D)materials have stimulated tremendous scientific and industrial interests due to their diverse and tunable physical,chemical,and mechanical properties.The scalable production of high-quality wafer-scale 2D materials has become significantly essential to bring us closer to practical industrial applications,particularly in electronic devices.Vapor-phase growth provides attractive opportunities for the synthesis of large-area and high-quality 2D materials.In this review,we will emphasize vapor-phase growth strategies from three aspects,including suppressing nucleation,seamless stitching,and evolutionary selection growth.We discuss the general understanding of the related fundamental mechanism and specific parameter optimization from precursors and substrate design to the adjusting of growth parameters(temperature and pressure).Meanwhile,we present other strategies to produce various kinds of wafer-scale 2D materials.Finally,we conclude the current challenges and future directions in this developing field.This work may inspire researchers to better design routes in the synthesis of wafer-scale 2D materials with high quality. 展开更多
关键词 two-dimensional materials vapor-phase growth wafer scale
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Enhanced conductivity and stability of Prussian blue cathodes in sodium-ion batteries by surface vapor-phase molecular selfassembly 被引量:3
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作者 Tao Yuan Xiaopan Fu +4 位作者 Yuan Wang Mingjie Li Shuixin Xia Yuepeng Pang Shiyou Zheng 《Nano Research》 SCIE EI CSCD 2024年第5期4221-4230,共10页
With many merits such as facile synthesis,economy,and relatively high theoretical capacity,Prussian blue analogs(PBAs)are considered promising cathode materials for sodium-ion batteries(SIBs).However,their practical a... With many merits such as facile synthesis,economy,and relatively high theoretical capacity,Prussian blue analogs(PBAs)are considered promising cathode materials for sodium-ion batteries(SIBs).However,their practical applications still suffer from a low actual specific capacity and inferior stability owing to the imperfect crystallinity,irreversible phase transition,and low intrinsic conductivity.Herein,a surface-modification technique for vapor-phase molecular self-assembly was developed to prepare Fe-based PBAs,specifically sodium iron hexacyanoferrate(NaFeHCF),with a uniform conductive polymer protective layer of polypyrrole(PPy)on the surface,resulting in NaFeHCF@PPy.The incorporation of a PPy protective layer not only improves the electronic conductivity of NaFeHCF@PPy,but also effectively mitigates the dissolution of Fe-ions during cycling.Specifically,this advanced vapor-phase technique avoids Fe^(2+)oxidation and Na^(+)loss during liquid-phase surface modification.The NaFeHCF@PPy exhibited a remarkably enhanced cycling performance,with capacity retentions of 85.6%and 69.1%over 500 and 1000 cycles,respectively,at 200 mA/g,along with a superior rate performance up to 5 A/g(fast kinetics).Additionally,by adopting this strategy for Mn-based PBAs(NaMnHCF@PPy),we further demonstrated the universality of this method for PBA cathodes in SIBs. 展开更多
关键词 sodium-ion battery CATHODE Prussian blue analogs surface modification vapor-phase molecular self-assembly
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Rational construction of multiple hollow silicalite-1 zeolite with enhanced quasi acidity for robust vapor-phase Beckmann rearrangement 被引量:3
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作者 Peng Zhang Xianfeng Yi +9 位作者 Changjiu Xia Xinxin Peng Shuai Zhang Chengxiang Li Anmin Zheng Xiaoxin Zhang Yibin Luo Lifeng Cui Fuhong Yu Xingtian Shu 《Nano Research》 SCIE EI CSCD 2023年第5期7958-7966,共9页
Developing efficient and stable zeolites for vapor-phase Beckmann rearrangement of cyclohexanone oxime is still a great challenge to realizeε-caprolactam(CPL)green production.In this work,the hierarchical porous sili... Developing efficient and stable zeolites for vapor-phase Beckmann rearrangement of cyclohexanone oxime is still a great challenge to realizeε-caprolactam(CPL)green production.In this work,the hierarchical porous silicalite-1 zeolites with multiple hollow structure(S-1-M)are explored by in-situ desilication−recrystallization post-treatment of spongy highway-like zeolites(S-1-S),which are synthesized through silanization synthesis of conventional bulky silicalite-1(S-1).Compared to S-1,S-1-M achieves superior catalytic performance,with improving the CPL selectivity from 85.7%to 94.1%and prolonging the catalyst lifetime from 74 to 126 h at a weight hourly space velocity(WHSV)of 6 h^(−1).Comprehensive physiochemical studies demonstrate that the highly dispersed intracrystalline cavities within S-1-M endow greater mass diffusion and better quasi acidity inducing by the enhanced H-bonds among abundant H-bonded silanols,which is cooperatively responsible for its superior catalytic performance. 展开更多
关键词 hollow silicalite-1 H-bonded silanols quasi acidity vapor-phase Beckmann rearrangement
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丙酸丙酯与正戊醇二元体系在101.3 kPa压力下气液相平衡研究
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作者 王琳 王思茜 +1 位作者 张雪珂 李入林 《南阳师范学院学报》 2026年第1期42-46,共5页
使用气液相平衡测量装置和阿贝折光仪,采用折光率分析法对101.3 kPa下的丙酸丙酯-正戊醇二元体系气液相平衡关系进行研究,得到了其在101.3 kPa下的气液相平衡数据。采用Herington面积积分法对实验数据进行热力学一致性检验,在此基础上... 使用气液相平衡测量装置和阿贝折光仪,采用折光率分析法对101.3 kPa下的丙酸丙酯-正戊醇二元体系气液相平衡关系进行研究,得到了其在101.3 kPa下的气液相平衡数据。采用Herington面积积分法对实验数据进行热力学一致性检验,在此基础上绘制了该二元体系的t-x-y、x-y相图。采用Wilson活度系数模型对实验数据进行模拟,得到了二元作用参数。结果表明,Wilson模型对应的气相组成平均相对偏差为0.1632%,平衡温度t平均相对偏差为0.03251%,预测数据与实验数据吻合良好,该模型适合模拟常压下丙酸丙酯-正戊醇体系的分离工艺。 展开更多
关键词 丙酸丙酯 正戊醇 气液相平衡 WILSON方程
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Vapor Deposition Engineering for Thin-Film Microbatteries:From Nanoscale Ionics to Interface-Integrated Architectures
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作者 Mingming Zheng Xinrui Xu +5 位作者 Xiaofei Wang Haibin Lin Changmin Hou Mustafa Khan Jinlong Zhu Songbai Han 《Nano-Micro Letters》 2026年第5期445-487,共43页
The rapid proliferation of microelectronics,coupled with the advent of the internet ofthings(IoT)era,has created an urgent demand for miniaturized,integrable,and reliable on-chip energystorage systems.All-solid-state ... The rapid proliferation of microelectronics,coupled with the advent of the internet ofthings(IoT)era,has created an urgent demand for miniaturized,integrable,and reliable on-chip energystorage systems.All-solid-state thin-film microbatteries(TFMBs),distinguished by their intrinsicsafety,compact design,and compatibility with microfabrication techniques,have emerged as promisingcandidates to power next-generation IoT devices.Nevertheless,in contrast to the well-establisheddevelopment of conventional lithium-ion batteries,the advancement of TFMBs remains at an earlystage,facing persistent challenges in materials innovation,interface optimization,and scalable manufacturing.This review critically examines the pivotal role of vapor deposition technologies,includingmagnetron sputtering,pulsed laser deposition,thermal/electron-beam evaporation,chemical vapordeposition,and atomic layer deposition,in the fabrication and performance modulation of TFMBs.We systematically summarize recent progress in thin-film electrodes and solid-state electrolytes,withparticular emphasis on how deposition parameters dictate crystallinity,lattice orientation,and ionictransport in functional layers.Furthermore,we highlight strategies for solid-solid interface engineering,three-dimensional structural design,andmultifunctional integration to enhance capacity retention,cycling stability,and interfacial compatibility.Looking ahead,TFMBs are expectedto evolve toward multifunctional platforms,exhibiting mechanical flexibility,optical transparency,and hybrid energy-harvesting compatibility,thereby meeting the heterogeneous energy requirements of future IoT ecosystems.Overall,this review provides a comprehensive perspective onvapor-phase-enabled TFMB technologies,delivering both theoretical insights and technological guidelines for the scalable realization of highperformancemicroscale power sources. 展开更多
关键词 Thin-film microbatteries vapor-phase deposition techniques Nanoscale ionic conductivity Interfacial engineering Microdevice integration
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微泡群强化汽化的高效蒸发器研究
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作者 张瑞敏 蔡灏亭 +2 位作者 佟薇 刘军 赵玉刚 《空气动力学学报》 北大核心 2026年第1期118-127,共10页
提高蒸发器汽化效率对能源管理与强化传热至关重要。为探索高效蒸发方法,本研究提出一种通过主动通入微气泡群以强化工质汽化的新技术。实验采用以微孔泡沫钛网制成的微气泡发生器,通过改变操作模式(持续加热/无加热)、泡沫钛平均孔隙(2... 提高蒸发器汽化效率对能源管理与强化传热至关重要。为探索高效蒸发方法,本研究提出一种通过主动通入微气泡群以强化工质汽化的新技术。实验采用以微孔泡沫钛网制成的微气泡发生器,通过改变操作模式(持续加热/无加热)、泡沫钛平均孔隙(2,5,10μm)及气体流量(1~15 NL/min)等条件,量化研究其对蒸发效果(出汽量、液体温降)的影响,并结合高速摄像对气泡动力学行为进行机理分析。结果表明,在无加热模式下,通入平均孔隙为10μm、流速为15 NL/min的微泡群时,温度降幅达30℃,对应出汽量达到未通气泡时的38倍;在持续加热模式下,相同参数的微泡群使温度下降约15℃,出汽量提升至未通气泡时的1.7倍。机理研究表明,微气泡群的引入大幅增加了气液相变界面面积,其上升过程带来的扰动及内部不可凝气体对蒸汽分压的改变,共同加速了界面处的汽化过程,从而实现蒸发效率的提升。该方法无需外场作用或表面改性,操作简便,为强化蒸发提供了新途径。 展开更多
关键词 相变换热 微泡群 蒸发 汽化 传热传质 蒸发器
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扰流管道内过饱和度分布的模拟研究
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作者 张军 李安进 代安稳 《东南大学学报(自然科学版)》 北大核心 2025年第3期895-902,共8页
为探究扰流管道中过饱和度的分布特征,使用Fluent流体仿真软件对管内传热传质模型进行模拟计算。首先,分析了扰流管内的流动特征;其次,分析了扰流管内不同径向位置的过饱和度分布特征,并考察了入口气流温度、入口气流速度、入口气流相... 为探究扰流管道中过饱和度的分布特征,使用Fluent流体仿真软件对管内传热传质模型进行模拟计算。首先,分析了扰流管内的流动特征;其次,分析了扰流管内不同径向位置的过饱和度分布特征,并考察了入口气流温度、入口气流速度、入口气流相对湿度等因素对过饱和度的影响;最后,对比研究了扰流管与直圆管过饱和度分布特征。计算结果表明,气流在挡板后会形成回流漩涡,在涡的影响下,管中心气流的湍流热扩散系数明显提高。不同径向位置在挡板处的过饱和度分布特点不同,管中心的过饱和度在挡板作用下提高,而管壁处的过饱和度在挡板作用下降低。增大进口气体与壁面的温差能有效提高过饱和度,当进口气体与壁面的温差保持不变,保持较低的进口气体温度可以使管内具有更高的平均过饱和度。降低入口气流速度能提高管内平均过饱和度。挡板能有效提高管中心过饱和度水平,改善过饱和度均匀性。 展开更多
关键词 细颗粒物 水汽相变 过饱和度 Fluent流体仿真软件
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波形微通道内HFE-7100的流动沸腾换热特性
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作者 王迎慧 龚莹 王耀 《江苏大学学报(自然科学版)》 北大核心 2025年第4期417-423,共7页
为降低受热壁面温度、提升壁温分布均匀性,针对HFE-7100在波形微通道内的流动沸腾换热过程开展数值模拟,分析其结构、加密方式对工质在通道内流动沸腾换热的作用.计算结果表明:微通道全程加密(增大波幅与波距之比,从0.04增至0.08),通道... 为降低受热壁面温度、提升壁温分布均匀性,针对HFE-7100在波形微通道内的流动沸腾换热过程开展数值模拟,分析其结构、加密方式对工质在通道内流动沸腾换热的作用.计算结果表明:微通道全程加密(增大波幅与波距之比,从0.04增至0.08),通道出口段的汽泡等效直径减小,汽液两相的片段环状流得到抑制,但通道进出口压降增幅明显(最大增幅达140.54%);局部加密微通道的上游、中游或下游,均可有效抑制出口段片段环状流的出现,降低受热壁面温度,改善壁温分布均匀性;比较发现,下游局部加密方式降低微通道内的汽泡生长速率更为显著,壁温及分布的调控效果与全程加密方式相当,但进出口压降可减小34.23%.综合分析,微通道下游局部加密方式可以更好地改善波形微通道的流动沸腾换热. 展开更多
关键词 波形微通道 流动沸腾 汽泡 汽液两相流 壁温
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高均匀性6英寸GaN厚膜的高速率HVPE生长研究 被引量:1
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作者 许万里 甘云海 +4 位作者 李悦文 李彬 郑有炓 张荣 修向前 《人工晶体学报》 北大核心 2025年第1期11-16,共6页
氢化物气相外延(HVPE)是制备GaN单晶衬底的关键技术,由于生长速率较高,如何控制大尺寸GaN高速率高均匀性生长对于获得高质量GaN衬底具有重要意义。本文针对自主设计研制的6英寸(1英寸=2.54 cm)GaN衬底用HVPE设备,通过数值模拟和实际生... 氢化物气相外延(HVPE)是制备GaN单晶衬底的关键技术,由于生长速率较高,如何控制大尺寸GaN高速率高均匀性生长对于获得高质量GaN衬底具有重要意义。本文针对自主设计研制的6英寸(1英寸=2.54 cm)GaN衬底用HVPE设备,通过数值模拟和实际生长实验,研究了工艺参数如源气体与衬底距离D、分隔气体、HCl流量、NH_(3)载气流量等对高速率生长GaN膜厚度均匀性的影响。数值模拟与生长实验结果发现,采用自研HVPE设备生长GaN厚膜具有高生长速率和高厚度均匀性等特点。研究表明,引入分隔气体及适当增大D值可以有效促进GaCl气体向样品边缘扩散,从而显著提升大尺寸外延厚膜的均匀性。采用最终优化工艺条件获得了厚度约11μm的6英寸GaN厚膜,其厚度不均匀性约±1.5%,生长速率大于60μm/h;随着生长时间的增加,生长速率增大,在生长时间为3 h时,6英寸GaN厚膜厚度达到约700μm,生长速率增大至200μm/h以上,且厚度不均匀性仍在±5%以内。 展开更多
关键词 氮化镓 氢化物气相外延 晶体生长 数值模拟 厚度不均匀性
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基于滤片-吸附管串联捕集的气相色谱-质谱法分析卷烟主流烟气全成分 被引量:1
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作者 李俊杰 刘百战 +5 位作者 张玮 虞桂君 戚大伟 费婷 吴达 束茹欣 《理化检验(化学分册)》 北大核心 2025年第9期1009-1024,共16页
为同时、高效检测卷烟主流烟气全成分,采用自制活性炭吸附管,提出了题示方法,并应用于3R4F参比卷烟的检测。用转盘型吸烟机抽吸卷烟,用直径为92 mm的剑桥滤片捕集卷烟主流烟气粒相物,透过滤片的气相部分通过自制活性炭吸附管(内装0.5 g... 为同时、高效检测卷烟主流烟气全成分,采用自制活性炭吸附管,提出了题示方法,并应用于3R4F参比卷烟的检测。用转盘型吸烟机抽吸卷烟,用直径为92 mm的剑桥滤片捕集卷烟主流烟气粒相物,透过滤片的气相部分通过自制活性炭吸附管(内装0.5 g活性炭)捕集。卷烟抽吸完毕后,收集吸附管及滤片,用二氯甲烷淋洗,加入含2 g·L^(-1)乙酸异丁酯、己酸异丁酯、十一酸乙酯、十七烷酸乙酯的异丙醇溶液(内标),振荡萃取30 min后取上层滤出清液,采用气相色谱-质谱法分析。对检出的未知成分,通过解卷积后采用NIST质谱库检索定性,并辅以保留指数比对确证。结果表明:该方法能够完全捕集卷烟主流烟气全成分,共准确鉴定出257种成分,包括气相成分65种,粒相成分105种,有机蒸汽相(气粒两相共存)成分87种;251种成分的半定量分析结果相对标准偏差(RSD,n=6)不大于10%。建立了19种代表性烟气成分(含气相成分、粒相成分及有机蒸汽相成分)的定量分析方法,19种代表性烟气成分的质量浓度在一定范围内和其峰面积与内标峰面积比值呈线性关系,检出限(3S/N)为3.3~22.4 ng·支^(-1)。按照标准加入法进行回收试验,回收率为79.0%~115%,测定值的RSD(n=6,日内和日间精密度)均小于10%。 展开更多
关键词 主流烟气 活性炭捕集 烟气全成分 有机蒸汽相 气相色谱-质谱法
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