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Regularities for the Non-yrast Bands of the Even- Even Nuclei

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Chinese Physics Letters 1996年第2期13卷 85-88页

作者： ZHAO Yu-min XING Xiang-jun QING Di CHEN yan Department of Physics Nanjing UniversityNanjing 210008 Department of Physics Southeastern UniversityNanjing 210018

By the enlightmenf of the anharmonic vibrator description for the *** bands of the even-even 38≤Z≤82 nuclei with 2.05≤R(=E_(4)_(1)+/E_(2)^(+)_(1))≤3.15,a similar regularity for the non-yrast bands is *** systematics suggests that the excitations of the non-yrast bands may be regarded as the multi-phonon excitations above the corresponding bandhead,or the intrinsic states.

关键词： states. bands excitation

6~24岁超重/肥胖儿童青少年抑郁及焦虑症状检出率Meta分析

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宁夏医科大学学报 2024年第4期46卷 394-399页

作者：田梅马晓燕丁文清曹娟马艳李静宁夏医科大学公共卫生学院银川750004

目的评估6~24岁超重/肥胖儿童青少年抑郁及焦虑症状检出率。方法系统检索中国知网、万方数据、重庆维普、中国生物医学文献数据库和PubMed,搜集有关超重/肥胖儿童青少年抑郁及焦虑症状检出率的文献,检索时限均由建库至2022年12月。由... 详细信息

目的评估6~24岁超重/肥胖儿童青少年抑郁及焦虑症状检出率。方法系统检索中国知网、万方数据、重庆维普、中国生物医学文献数据库和PubMed,搜集有关超重/肥胖儿童青少年抑郁及焦虑症状检出率的文献,检索时限均由建库至2022年12月。由2位研究者独立筛选文献、提取数据并评价纳入研究的偏倚风险后,采用Stata 14.0软件进行Meta分析。结果超重/肥胖儿童青少年中,抑郁及焦虑症状的总体检出率分别为21%(95%CI:17%~25%,I2=95.8%)和20%(95%CI:13%~27%,I2=96.7%);超重/肥胖儿童青少年比非超重/肥胖儿童青少年更有可能有抑郁症状(OR=1.62,95%CI:1.25~2.10,P<0.05)和焦虑症状(OR=2.13,95%CI:1.11~4.10,P<0.05)。结论抑郁及焦虑症状在超重/肥胖儿童青少年中较常见,超重/肥胖儿童青少年有较高的抑郁及焦虑风险。为了减少抑郁及焦虑风险,应定期进行有效筛查和干预。

关键词：超重/肥胖儿童青少年抑郁症状焦虑症状

Well-construction of Zn_(2)SnO_(4)/SnO_(2)@ZIF-8 core-shell hetero-structure with efficient photocatalytic activity towards tetracycline under restricted space

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Chinese Journal of Chemical Engineering 2022年第12期52卷 45-55页

作者： Jiafei Wu Yuning Jin Danping Wu Xiaoying yan Na ma Wei Dai Key Laboratory of the Ministry of Education for Advanced Catalysis materials College of Chemistry and Life ScienceZhejiang Normal UniversityJinhua 321004China National Center for Nanoscience and Technology Beijing 100190China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China

Nowadays,efficient removal of antibiotic(***,TC) from water bodies has been of great global ***,a novel Zn_(2)SnO_(4)/SnO_(2)@ZIF-8 photo-catalyst was first synthesized by a facile selfassembly in-situ growth ***_(2)SnO_(4)/SnO_(2)@ZIF-8 exhibits a remarkable photocatalytic activity towards TC under visible-light driven with a rapid rate constant of 1.5 × 10^(-2)min^(-1), and a removal efficiency of 81.2%,which is superior to some catalysts in the ***,the photocatalytic activity of Zn_(2)SnO_(4)/SnO_(2)@ZIF-8 could still remain ~77% after the fifth cycle,indicating its good stability and *** remarkable performances of adsorption and photocatalytic were attributed to associative effects of catalytic activity of Zn_(2)SnO_(4)/SnO_(2)and the unique porous nanostructure and stability of *** work could aid the future design and preparation of novel MOFs composite catalysts for efficient elimination of antibiotics from water.

关键词： Degradation Catalyst Tetracycline ZIF-8 Zn_(2)SnO_(4)/SnO_(2) Adsorption

The reionization of He II and the temperature evolution of the intergalactic medium

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Research in Astronomy and Astrophysics 2014年第4期14卷 373-389页

作者： Yun-Chuan Yu Chang-Shuo yan You-jun Lu National Astronomical Observatories Chinese Academy of Sciences

A number of observations suggest that He II in the intergalactic medium （IGM） was fully ionized at z-3, probably by quasi-stellar objects （QSOs）. Here we construct a simple model of a QSO to study the reionization of He II and the corre- sponding thermal evolution of the IGM. We assume that QSOs are triggered by major mergers of dark matter halos, and the luminosity evolution of individual QSOs is de- scribed by an initial accretion stage with a constant Eddington ratio and then a power- law decay driven by long term disk evolution or fueling. Once a QSO is triggered, it immediately ionizes its surrounding area as an ionized bubble. The resulting changes in size and volume of the bubble are determined by the luminosity evolution of the central QSO. With the emergence of more and more bubbles, they eventually over- lap each other and finally permeate the whole universe. During the He II reionization, the IGM temperature increases due to the photoheating by the ionization processes. Applying the bubble model and considering various heating and cooling mechanisms, we trace the thermal evolution of the IGM and obtain the average IGM temperature as a function of redshift, which is very consistent with observations. The increase in IGM temperature due to the reionization of He II may be determined more accurately in the future, which may put robust constraints on the QSO model and the physics of He II reionization.

关键词： cosmology: theory -- intergalactic medium: QSO

Serum folate status among blood donors in south-central China

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Journal of Innovative Optical Health Sciences 2022年第2期15卷 42-48页

作者： yan ma Huan Deng Mingdi He Ru yang Gang Shen Wuhan Blood Center-Huazhong University of Science and Technology United Hematology Optical Imaging Center Hubei Institute of Blood Transfusion Wuhan Blood Center WuhanHubei 430030P.R.China Wuhan Blood Center-Huazhong University of Science and Technology United Hematology Optical Imaging Center Britton Chance Center for Biomedical Photonics School of Optical and Electronic Information-Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology 430074 P.R.China

Folate deficiency has been confirmed to be related to various ***,there are few reports on the folate status of Chinese *** study aims to evaluate the serum folate status of blood donors in south-central *** this study,248 blood donors were *** information on subjects was collected by a brief questionnaire concerning alcohol consumption habits,smoking habits,fruit and vegetable consumption and physical *** serum folate concentration was measured by electrochemiluminescence *** geometric mean serum folate concentration was 13.4 nmoll-1(95%CI,12.7-14.1).The prevalence of serum folate concentrations below 6.8 nmoll-1 was 5.2%(95%CI,2.5-8.0).There were significant differences in serum folate concentrations with respect to sex(p-values<0.05),age(p-values<0.05),fruit and vegetable consumption(p-values<0.05),and alcohol consumption habits(p-values<0.05).The concentration of serum folate increased with age(p-values<0.05)and fruit and vegetable consumption(p-values<0.05).Individuals with an age of 30 years or younger were nearly 3.5 times as likely as those aged over 30 years to have an insufficient level of serum folate(OR=3.48;95%CI:1.01-11.99).An age of 30 years or younger was a risk factor for folate *** blood donors had sufficient serum folate concentrations in south-central *** surveys of folate status should be implemented in China.

关键词： Serum folate folate status folate de¯ciency blood donors folate concentrations

CH_4 Concentrations and Emissions from Three Rivers in the Chaohu Lake Watershed in Southeast China

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Journal of Integrative Agriculture 2012年第4期11卷 665-673页

作者： yanG Li-biao LI Xin-yan yan Wei-jin ma Pei WANG Jia-ning Institute of Geographical Science and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P.R.China Graduate University Chinese Academy of Sciences Beijing 100049 P.R. China

This study was conducted at three rivers of the Chaohu Lake watershed during the summer season of 2008,aiming to investigate the diurnal variations of dissolved CH4 concentrations and emissions,as well as the dynamics of CH4 accumulation emission rates over consecutive 72 *** results showed that CH4 concentrations in the Fengle,Hangbu,and Nanfei rivers ranged from 56.33-124.79,160.82-341.03,and 213.49-716.81 nmol L-1,respectively,over a daily cycle;while the saturation of CH4 ranged from 188.72-418.07,538.74-1 142.46,and 715.23-2 401.38%,respectively,which indicated that surface waters were in all cases oversaturated with respect to the *** obvious diurnal variation pattern of the dissolved CH4 concentrations demonstrated a higher value during daytime but a lower value for night ***,the highest dissolved CH4 concentrations were detected in the Nanfei River which received substantial urban wastewater ***4 emissions measured with floating chambers ranged from 5.82-15.46,5.77-8.41,and 13.51-49.25 mg C m-2 h-1 for the Fengle,Hangbu,and Nanfei rivers,respectively,over a daily *** higher CH4 emissions were also observed from the Nanfei *** accumulative CH4 emissions for each river increased with time,while a decline trend on the accumulation rates was investigated over the consecutive 72 h.

关键词： methane concentration emission river diurnal variation

Corrosion Inhibition of Galvanized Steel in NaCl Solution by Tolytriazole

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 471-480页

作者： yanhong yan Hongwei Shi jun Wang Fuchun Liu En-Hou Han CAS Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences Department of Chemistry Northeastern University

Corrosion inhibition of tolytriazole for galvanized steel was studied in 5 mM NaCl by using potentiodynamic polarization and electrochemical impedance spectroscopy(EIS), scanning vibrating electrode technique(SVET). The results of EIS and polarization tests indicate that tolytriazole is effective in corrosion inhibition of galvanized steel. As the concentration of tolytriazole is increased to 0.01 M, the inhibiting efficiency reaches above 98%. The low values of anodie and cathodic current density in SVET maps suggest that the complex of tolytriazole with galvanized steel inhibits the anodic and cathodie reactions of corrosion of zinc. The adsorption behaviour of tolytriazole is found to conform to Langmuir adsorption isotherm, which is typical chemical adsorption.

关键词： Tolytriazole Galvanized steel Corrosion inhibition Potentiodynamic curves Electrochemical impedance spectroscopy SVET

3D Interconnected Honeycomb‑Like Multifunctional Catalyst for Zn-Air Batteries

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Nano-Micro Letters 2023年第2期15卷 212-227页

作者： Tianxu Jin junli Nie Mei Dong Binling Chen jun Nie Guiping ma State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China College of Engineering Mathematics and Physical ScienceUniversity of ExeterExeter EX44QFUK

Developing high-performance and low-cost electrocatalysts is key to achieve the clean-energy ***,a dual regulation method is proposed to prepare a 3D honeycomb-like carbon-based catalyst with stable Fe/Co *** atoms are highly dispersed and fixed to the polymer microsphere,followed by a high-temperature decomposition,for the generation of carbon-based catalyst with a honeycomb-like *** as-prepared catalyst contains a large number of Fe/Co nanoparticles(Fe/Co NPs),providing the excellent catalytic activity and durability in oxygen reduction reaction,oxygen evolution reaction and hydrogen evolution *** Zn-air battery assembled by the as-prepared catalyst as air cathode shows a good charge and discharge capacity,and it exhibits an ultra-long service life by maintaining a stable charge and discharge platform for a 311-h *** X-ray absorption fine structure characterization and density functional theory calculation confirms that the Fe doping optimizes the intermediate adsorption process and electron transfer of Co.

关键词： Fe/Co nanoparticles Core-shell microspheres Multifunctional catalyst Stability

Nonlinear characterization and performance optimization for broadband bistable energy harvester

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Acta Mechanica Sinica 2020年第3期36卷 578-591页

作者： Ting Tan Zhimiao yan Kejing ma Fengrui Liu Linchuan Zhao Wenming Zhang State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

As two crucial indicators of bistable energy harvesting performance,band width and power amplitude are simultaneously investigated for obtaining the synergy *** this goal,a nonlinear electromechanical-coupled distributed-parameter model of the bistable piezoelectric energy harvester is *** on the electromechanical decoupled method,approximate higher-order analytical solutions of the beam displacement,harvested power and effective bandwidth are *** cubic-function discriminant of the analytical solution is introduced to determine the nonlinear excitation-frequency boundaries of multiple solutions and power *** stability of the multiple solutions is analyzed through Jacobi matrix of the modulation *** resonance is *** and downward sweep experiments and numerical solutions of time history curves,phase portraits and power spectra confirm the analytical *** realize optimized broadband energy harvesting,the parametric study on the coefficients of the linear and cubic elastic external forces with the corresponding optimal load resistance is *** the nonlinear hardening case,more positive linear coefficient is *** the nonlinear softening case,the cubic coefficient slightly larger than its optimal value is recommended at each given linear *** tuning the load resistance and linear and cubic coefficients of the external force,broadband bistable energy harvesting with optimized power is realized.

关键词： Vibration energy harvesting Bistable solution Broadband Superharmonic resonance