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Polyarylene Ether Nitrile and Titanium Dioxide Hybrids as Thermal Resistant Dielectrics

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Chinese Journal of Polymer Science 2021年第2期39卷 211-218,I0007页

作者： Ren-Bo Wei Chen-hao zhan Yang Yang Peng-Lin He Xiao-Bo Liu Research Branch of Advanced Functional Materials School of Materials and EnergyUniversity of Electronic Science and Technology of ChinaChengdu 610054China School of Chemical Engineering Northwest UniversityXi’an 710069China

With the expanding application of capacitors,thermal resistant dielectric materials are in high demand due to the increasing harsh environments where the capacitors are needed and the heat generated by the ***,we present polyarylene ether nitrile and titanium dioxide hybrids which can be used as thermal resistant dielectrics for these *** modified titanium dioxide(TiO_(2)-CN)and phthalonitrile end-capped polyarylene ether nitrile(PEN-Ph)are firstly *** being cast into TiO_(2)-CN/PEN nanocomposite films,these composites self-crosslink upon heating at 320℃for 4 h,forming the polyarylene ether nitrile and titanium dioxide hybrids(TiO_(2)-PEN).Improved dielectric constants which are stable from room temperature to 200℃of these hybrids are observed,indicating the potential application of the hybrids as thermal resistant dielectrics.

关键词： Hybrid TiO2 Polyarylene ether nitrile Thermal resistance Dielectric properties

Poly(arylene ether nitrile)Dielectric Film Modified by Bi_(2)S_(3)/rGO-CN Fillers for High Temperature Resistant Electronics Fields

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Chinese Journal of Polymer Science 2022年第11期40卷 1441-1450页

作者： Li-Fen Tong Liang He Chen-hao zhan Yun-Qing Xia Xiao-Bo Liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu610054China Sichuan Province Engineering Technology Research Center of Novel CN Polymeric Materials Chengdu610054China

High-quality film capacitors are widely used in many fields such as new energy vehicles,electronic communications,etc.,due to their advantages in wide frequency response and low dielectric *** dielectric film is a crucial part of the film capacitor,and its properties have an important impact on the performance and use conditions of the film *** this work,a novel high-temperature-resistant dielectric film was ***,the Bi_(2)S_(3)/rGO-CN fillers were prepared by hydrothermal method combined with cyanation treatment,and then added to the poly(arylene ether nitrile)(PEN)matrix to prepare the dielectric film materials(PEN/Bi_(2)S_(3)/rGO-CN).After high temperature treatment,the fillers Bi_(2)S_(3)/rGO-CN reacted with the PEN matrix,and the composites materials transformed into a thermosetting hybrid film(PEN-Bi_(2)S_(3)/rGO)with gel content of 97.88%.The prepared hybrid dielectric films did not decompose significantly before 400℃,and showed a glass transition temperature(Tg)of up to 252.4℃,which could increase the effective use temperature of the *** with the composite films without heat treatment,they exhibit better mechanical properties,with further improvement in tensile strength and elastic modulus,and a decrease in elongation at *** dielectric constant of the hybrid films can be up to 6.8 while the dielectric loss is only about 0.02 at 1 ***,the hybrid films showed excellent dielectric stability during temperature changes,and remain relatively stable before 250℃,which is suitable as a high-temperature-resistant high-dielectric material and is more advantageous for practical applications.

关键词： Poly(arylene ether nitrile) Bismuth sulfide Graphene oxide High-temperature-resistant Dielectric properties

Analysis and prediction of research hotspots and trends in pediatric medicine from 2,580,642 studies published between 1940 and 2021

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World Journal of Pediatrics 2023年第8期19卷 793-797页

作者： Ze‑Ye Liu Yuan Huang Jing Xu Li Xiang zhan‑hao Su Yi‑Wei Liu hao zhang Department of Structural Heart Disease National Center for Cardiovascular DiseaseFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesPediatric Cardiac Surgery CenterFuwai HospitalChinese Academy of Medical Sciencesand Peking Union Medical CollegeBeijingChina State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesFuwai HospitalChinese Academy of Medical Sciencesand Peking Union Medical CollegeBeijingChina Heart Center and Shanghai Institute of Pediatric Congenital Heart Disease Shanghai Children’s Medical CenterNational Children’s Medical CenterShanghai Jiaotong University School of MedicineNo.1678 Dongfang RoadShanghai 200127China Department of Cardiovascular Surgery Guangdong Cardiovascular InstituteGuangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510060China Shanghai Clinical Research Center for Rare Pediatric Diseases Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China

From 1990 to 2019,there has been a substantial increase in the global population from 5.3 billion to 7.7 billion(about 44.6%)[1,2].Simultaneously,the global death population among people under 20 years of age has increased from 6.22 million to 13.93 million,accounting for an increase of 124%[1,2,3].This means that the mortality rate of children/adolescents is almost three times higher than the growth rate of the global population.

关键词： mortality population. pediatric

Variational quantum eigensolvers by variance minimization

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Chinese Physics B 2022年第12期31卷 41-48页

作者： Dan-Bo zhang Bin-Lin Chen zhan-hao Yuan Tao Yin Guangdong-Hong Kong Joint Laboratory of Quantum Matter Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China Guangzhou Educational Infrastructure and Equipment Center Guangzhou 510006China Yuntao Quantum Technologies Shenzhen 518000China

The original variational quantum eigensolver(VQE)typically minimizes energy with hybrid quantum-classical optimization that aims to find the ground ***,we propose a VQE based on minimizing energy variance and call it the variance-VQE,which treats the ground state and excited states on the same footing,since an arbitrary eigenstate for a Hamiltonian should have zero energy *** demonstrate the properties of the variance-VQE for solving a set of excited states in quantum chemistry ***,we show that optimization of a combination of energy and variance may be more efficient to find low-energy excited states than those of minimizing energy or variance *** further reveal that the optimization can be boosted with stochastic gradient descent by Hamiltonian sampling,which uses only a few terms of the Hamiltonian and thus significantly reduces the quantum resource for evaluating variance and its gradients.

关键词： quantum computing quantum algorithm quantum chemistry

Quantum verification of NP problems with single photons and linear optics

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Light(Science & Applications) 2021年第9期10卷 1750-1760页

作者： Aonan zhang hao zhan Junjie Liao Kaimin Zheng Tao Jiang Minghao Mi Penghui Yao Lijian zhang National Laboratory of Solid State Microstructures Key Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)and College of Engineering and Applied SciencesNanjing University210093NanjingChina Collaborative Innovation Center of Advanced Microstructures Nanjing University210093NanjingChina State Key Laboratory for Novel Software Technology Nanjing University210093NanjingChina

Quantum computing is seeking to realize hardware-optimized algorithms for application-related computational ***(nondeterministic-polynomial-time)is a complexity class containing many important but intractable problems like the satisfiability of potentially conflict constraints(SAT).According to the well-founded exponential time hypothesis,verifying an SAT instance of size n requires generally the complete solution in an O(n)-bit *** contrast,quantum verification algorithms,which encode the solution into quantum bits rather than classical bit strings,can perform the verification task with quadratically reduced information about the solution in O~(Õ−−√n)*** we realize the quantum verification machine of SAT with single photons and linear *** using tunable optical setups,we efficiently verify satisfiable and unsatisfiable SAT instances and achieve a clear completeness-soundness gap even in the presence of experimental *** protocol requires only unentangled photons,linear operations on multiple modes and at most two-photon joint *** features make the protocol suitable for photonic realization and scalable to large problem sizes with the advances in high-dimensional quantum information manipulation and large scale linear-optical *** results open an essentially new route toward quantum advantages and extend the computational capability of optical quantum computing.

关键词： quantum optics verify

One-pot synthesis of Fe_(x)O_(y)nanoparticles embedded within N-doped carbon layers as highly efficient and selective catalysts for the hydrogenation of nitroarenes

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Chinese Chemical Letters 2023年第6期34卷 323-328页

作者： Xiuzheng Zhuang Ke Jin Qi zhang Jianguo Liu Xinghua zhang hao zhan Longlong Ma Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China School of Energy Science and Engineering Central South UniversityChangsha 410083China

Inhibiting the side reactions while promoting hydrogenation are the main target for the production of functional anilines from nitroarenes;consequently,the preparation of an ideal catalyst to improve chemical selectivity is one of the hot *** this work,we provided an easy-to-prepare catalyst with Ndoped carbon layers,where the Fe_(x)O_(y)nanoparticles were encapsulated and distributed *** structural features of catalyst were characterized by several techniques,and the selected catalyst was next applied to the hydrogenation of nitrobenzene under varied conditions,involving temperature,holding period and H2 ***,we conducted the synthesis of more than 16 substrates for the corresponding anilines with varied functional *** hydrogenation protocol to gram-scale synthesis as well as lifecycle performance were also demonstrated in the batch reactor,together with the explanation of its catalytic ***,the present work provides an available preparation of simple but highly efficient catalysts for the production or aromatic amines,which will be benefit for the sustainable development of this field in near future.

关键词： Facile synthesis Iron-based catalyst Carbonaceous layers Nitroarenes reduction

Effects of modafinil on vestibular function during 24 hour sleep deprivation

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Frontiers of Medicine 2007年第2期1卷 226-229页

作者： zhan hao XIE Sujiang JIA Hongbo WEI Sihuang JING Baisheng Institute of Aviation Medicine Beijing 100036China

The aim of this research was to investigate the effects of modafinil,a new wake-promoting agent,on vestibular function during 24 h sleep deprivation(SD)so as to provide experimental evidence for the rational use of this drug among air *** young,healthy male volunteers were exposed to two 24 h periods of continuous wakefulness during the crossover ***,200 mg dose of modafinil was given,and one week later,a matching placebo was *** SD time started from 08:00 of the first day to 08:00 of the second *** were given at 0:00 on the second *** function was tested at 21:00 on the first day and 1,3,5,7 h after drug *** accuracy of saccade tracking and gains in visual-vestibular optokinetic reflex(VVOR)and optokinetic nystagmus(OKN)in the placebo group decreased during 24 h SD,especially at 01:00–05:00 on the second day,while OKN gains in the modafinil group increased *** were no significant differences in the other vestibular functional indices between the modafinil group and placebo *** 24 h SD can influence vestibular function to a certain degree,but modafinil may improve OKN.

关键词： sleep deprivation central nervous system agents wake-promoting agent modafinil vestibular function

Habitat associations of saplings and adults in an old-growth temperate forest in the Changbai mountains, northeastern China

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Forestry Studies in China 2011年第1期13卷 13-22页

作者： YE Ji hao zhan-qing XIE Peng LI Jing-gong Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 E R. China Graduate University of Chinese Academy of Sciences Beijing 100049 R R. China Jilin Provincial Academy of Forestry Sciences Changchun 130033 R R. China The Changbai Mountain Natural Reserve Administration Changbaishan 113613 R R. China

Species-habitat association analysis is useful to detect spatial arrangement of individual plants, to discover rules about the distribution of species and to generate hypotheses about the possible underlying process controlling observed structures. Quantifying methods were used to classify habitats in terms of topographical variables in a mixed temperate broad-leaved Korean pine forest of the Changbai mountains in northeastern China. All of the 625 20 m × 20 m quadrats of the plot could be unambiguously assigned to one of three habitat categories （low-plateau, high-plateau and slope）. Torus-translation tests were used to estimate species-habitat associations. Many species are clearly distributed in a biased fashion with respect to habitats. Fifteen （55.6%） out of 27 species showed strong positive or negative association with specific habitats. We compared species-habitat associations at the sapling and adult stages. Adjusted density values indicated few species exhibit extremely strong habitat associations. Only 9 out of 26 species had adjusted densities 〉 3 in the habitat for which they had strong positive affinity. Few species show the same associations at the small tree and large tree stages. Only 3 out of 22 occurring associations with a specific habitat appeared to have a consistent habitat association at the two stages. These results suggest that species-habitat associations exist in the 25-ha plot of the temperate forest of the Chang- bai mountains. Owing to limitations in our statistical methodology, we partly underestimated associations by ignoring rare species. Regeneration niches can contribute to co-existence, but regeneration niches due to habitat associations play a limited role in species co-existence, since most species show a similar trend in habitat associations at the sapling and adult stages. We should pay more attention to shifts in habitat associations, i.e. niche shifts at different stages of existence.

关键词： niche differentiation habitat association environmental heterogeneity saplings and adults life stages

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氟化氢铵氟化法合成氟化钆过程的基础研究

材料科学与工艺 2010年第5期18卷 653-656,661页

作者：郝占忠包头师范学院化学学院内蒙古包头014030

以Gd2O3和NH4HF2为原料,利用TG-DTA分析方法和控制变量实验方法,研究了氟化氢铵氟化法合成氟化钆过程的反应机理,考察了系统压力、温度、时间和原料摩尔比对氟化率、氟含量、氧含量和氮含量的影响规律.研究表明:合成过程包括NH4GdF4的... 详细信息

以Gd2O3和NH4HF2为原料,利用TG-DTA分析方法和控制变量实验方法,研究了氟化氢铵氟化法合成氟化钆过程的反应机理,考察了系统压力、温度、时间和原料摩尔比对氟化率、氟含量、氧含量和氮含量的影响规律.研究表明:合成过程包括NH4GdF4的低温缓慢合成反应、NH4HF2熔化后的NH4GdF4快速合成反应和高温时的NH4GdF4分解反应;氟化过程系统压力增加,氟化率和氟含量增加,氧含量降低,氮含量增加;温度升高,氟化率和氟含量增加,氧含量先降后升;氧含量随摩尔比增加而减少,氟含量随摩尔比增加而增大.

关键词：氟化钆氟化氢铵合成机理