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The effects of cold stimulation and exercise on human health
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作者 Jie Tian Jiangli Li +1 位作者 yunbo zhang Fengjuan Yang 《Frigid Zone Medicine》 2023年第3期176-185,共10页
Cold stimulation and exercise are two independent stimulus variables,each yielding unique impacts on human health.However,in many cases,individuals often encounter both factors simultaneously,particularly in colder re... Cold stimulation and exercise are two independent stimulus variables,each yielding unique impacts on human health.However,in many cases,individuals often encounter both factors simultaneously,particularly in colder regions where outdoor physical activity is prevalent.Despite numerous studies exploring the effects of cold exposure and exercise independently,only a limited number of comprehensive reviews have evaluated their combined influence on health.This review aims to bridge this gap by meticulously examining the potential benefits and detriments of both cold stimulation and exercise on human health.Specifically,the review focuses on their impacts on cardiovascular,respiratory,and immune function,as well as the favorable effects of moderate exercise on the human body.While evidence suggests that cold exposure can enhance health outcomes in certain disease contexts,it also poses risks,particularly for vulnerable populations.Furthermore,while moderate exercise is generally beneficial,engaging in physical activity in cold weather conditions can increase the risk of hypothermia,frostbite,and other cold-related injuries.Consequently,there is an urgent need to develop safe and effective guidelines for exercising in cold weather,particularly for individuals living in colder regions.This review emphasizes the necessity for further research on the combined effects of cold stimulation and exercise,with the goal of informing public health policies and guidelines for physical activity in cold weather conditions. 展开更多
关键词 cold exposure EXERCISE HEALTH cardiovascular disease
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细菌纤维素衍生的三维碳集流体用于无枝晶的锂金属负极 被引量:3
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作者 张云博 林乔伟 +5 位作者 韩俊伟 韩志远 李曈 康飞宇 杨全红 吕伟 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第2期142-150,共9页
锂金属是下一代高能量密度电池的关键负极,然而其实用化面临着一系列问题,主要包括循环过程中体积变化大、枝晶生长等。使用三维集流体是解决这些问题的有效方法,然而现有大多数三维集流体存在重量大、体积大、表面亲锂性差、成本高等... 锂金属是下一代高能量密度电池的关键负极,然而其实用化面临着一系列问题,主要包括循环过程中体积变化大、枝晶生长等。使用三维集流体是解决这些问题的有效方法,然而现有大多数三维集流体存在重量大、体积大、表面亲锂性差、成本高等问题。针对上述问题,本文以低成本的细菌纤维素为前驱体,通过直接碳化制备出具有连通网络的轻质三维碳集流体,其表面均匀分布的含氧官能团可以促进锂离子的均匀成核和沉积,有效抑制了枝晶生长。值得注意的是,该集流体的面密度仅为0.32 mg·cm^(−2),在3 mAh·cm^(−2)比容量的锂金属负极中质量占比仅为28.8%。电化学测试结果表明,该集流体在3 mA·cm^(−2)的高电流密度或4 mAh·cm^(−2)的高循环容量的工作条件下,稳定循环超过150次,并且在对称电池或与LiNi0.8Co0.15Al0.05匹配的全电池中也表现出良好的电化学性能。 展开更多
关键词 锂金属负极 细菌纤维素 三维集流体 锂枝晶 含氧官能团
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Effects of Different Nitrogen Treatments on N use Efficiency and Grain Yield of Mechanically-transplanted Hybrid Rice
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作者 Chang YE Ke LIU +4 位作者 Shaowen LIU Jian LU Mengtao GAO Bilin LU yunbo zhang 《Agricultural Science & Technology》 CAS 2017年第2期274-276,293,共4页
In order to investigate effects of topdressing on grain yield and N use efficiency of mechanically-transplanted hybrid rice, this experiment was conducted with 2-line hybrid rice cultivars, Quanliangyou 1 and Quanlian... In order to investigate effects of topdressing on grain yield and N use efficiency of mechanically-transplanted hybrid rice, this experiment was conducted with 2-line hybrid rice cultivars, Quanliangyou 1 and Quanliangyou 681 with 3 application levels of N fertilizer, N_0, N_1, N_2, respectively. The results showed that there were no significant differences in grain yields of the 2 varieties between treatments N_1 and N_2. It was indicated that N is not the factor which could limit grain yield within limited application levels of N fertilizer. High N fertilizer treatment could contribute to the formation of effective panicles and spikelets per panicle, but it could also lead to the decline in grain filling rate. It was suggested that lowering the amount of Nfertilizer could facilitate improvement of N-use efficiency. 展开更多
关键词 氮素利用效率 氮肥用量 籽粒产量 Hybrid 机械移植 籽粒灌浆速率 粮食产量 水稻品种
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Type division and controlling factor analysis of 3rd-order sequences in marine carbonate rocks
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作者 yunbo zhang Zongju Zhao +4 位作者 Genhou Wang Zaixing Jiang Mingjian Wang Min Zheng Shiben zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期289-298,共10页
Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehens... Type division and controlling factor analysis of 3rd-order sequence are of practical significance to tec-tonic analysis, sedimentary environment identification, and other geological researches. Based on the comprehensive analysis of carbon and oxygen isotope trends, paleobathymetry and spectral-frequency of representative well logs, 3rd-order sequences can be divided into 3 types: (a) global sea level (GSL) sequence mainly controlled by GSL change;(b) tectonic sequence mainly controlled by regional tectonic activity;and (c) composite sequence jointly controlled by GSL change and regional tectonic activity. This study aims to identify the controlling factors of 3rd-order sequences and to illustrate a new method for classification of 3rd-order sequences of the middle Permian strata in the Sichuan Basin, China. The middle Permian strata in the Sichuan Basin consist of 3 basin-contrastive 3rd-order sequences, i.e., PSQ1, PSQ2 and PSQ3. Of these, PSQ1 is a GSL sequence while PSQ2 and PSQ3 are composite sequences. The results suggest that the depositional environment was stable during the deposition of PSQ1, but was activated by tectonic activity during the deposition of the middle Permian Maokou Formation. 展开更多
关键词 Carbon isotope 3rd-Order sequence Milankovitch cycles Middle Permian strata Sichuan Basin
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Postoperative Radiotherapy and N2 Non-small Cell Lung Cancer Prognosis: A Retrospective Study Based on Surveillance, Epidemiology, and End Results Database
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作者 yunbo zhang Liping Zheng +4 位作者 Junqi Liu Jinqiu Li Jianguang zhang Jingjing Ma Yuxiu Song 《Journal of Oncology Research》 2021年第2期1-7,共7页
The purpose of this study is to clarify the significance of postoperative radiotherapy for N2 lung cancer.This study aimed to investigate the effect of postoperative radiotherapy on the survival and prognosis of patie... The purpose of this study is to clarify the significance of postoperative radiotherapy for N2 lung cancer.This study aimed to investigate the effect of postoperative radiotherapy on the survival and prognosis of patients with N2 lung cancer.Data from 12,000 patients with N2 lung cancer were extracted from the Surveillance,Epidemiology,and End Results database(2004-2012).Age at disease onset and 5-year survival rates were calculated.Survival curves were plotted using the Kaplan-Meier method.The univariate log-rank test was performed.Multivariate Cox regression were used to examine factors affecting survival.Patients’median age was 67 years(mean 66.46±10.03).The 5-year survival rate was 12.55%.Univariate analysis revealed age,sex,pathology,and treatment regimen as factors affecting prognosis.In multivariate analysis,when compared to postoperative chemotherapy,postoperative chemoradiotherapy was better associated with survival benefits(hazard ratio[HR]=0.85,95%confidence interval[CI]:0.813-0.898,P<0.001).Propensity score matching revealed that patients who had received postoperative chemoradiotherapy had a better prognosis than did patients who had received postoperative chemotherapy(HR=0.869,95%CI:0.817-0.925,P<0.001).Female patients and patients aged<65 years had a better prognosis than did their counterparts.Patients with adenocarcinoma had a better prognosis than did patients with squamous cell carcinoma.Moreover,prognosis worsened with increasing disease T stage.Patients who had received postoperative chemoradiotherapy had a better prognosis than did patients who had received postoperative chemotherapy.Postoperative radiotherapy was an independent prognostic factor in this patient group. 展开更多
关键词 Non-small cell lung cancer RADIOTHERAPY POSTOPERATIVE Prognosis
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Online preparation of high-quality BN coatings with atomic diffusion based on carbon-free water-soluble precursor
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作者 Yiang Du Bing Wang +5 位作者 yunbo zhang Quzhi Song Fuwen Wang Cheng Han Xiaoshan zhang Yingde Wang 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2024年第3期272-281,共10页
Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low dep... Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low deposition rate,high energy consumption,and utilization of multiple environmentally hazardous steps.To address these challenges,we propose a stable and efficient wet chemical deposition coating method for high-throughput online continuous preparation of boron nitride(BN)coatings on ceramic fibers under an ambient environment.Our process involves surface modification,in-situ wet chemical deposition,and heat treatment,and all seamlessly connecting with the ceramic fiber preparation process through continuous stretching.Hydrophilic groups were introduced via surface modification enhancing wettability of the fiber surface with impregnating solution.An in-situ reaction and atom migration improve uniformity and binding of the coating.As a result,outstanding impregnation and adhesion properties are achieved.A comprehensive analysis to evaluate the impact of the BN coatings was conducted,which demonstrates that the BN-coated fibers exhibit a remarkable 36%increase in tensile strength,a 133%increase in fracture toughness,and enhanced temperature resistance of up to 1600℃.It provides a secure and efficient platform for cost-effective production of functional and high-quality coatings through targeted surface modification and rapid stretching impregnation. 展开更多
关键词 polymer-derived ceramics SiC fibers wet chemical deposition atomic diffusion boron nitride(BN)coatings
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用于锂金属负极的轻质、高掺氮量碳纳米纤维基三维集流体(英文) 被引量:15
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作者 吴浩良 张云博 +6 位作者 Yaqian Deng 邓亚茜 黄志佳 张琛 贺艳兵 吕伟 杨全红 《Science China Materials》 SCIE EI CSCD 2019年第1期87-94,共8页
锂金属是未来二次电池实现高能量密度化的关键负极材料,然而,如何实现锂金属的均匀和无枝晶沉积是目前制约其实际应用的关键问题.本论文采用静电纺丝技术及高温碳化方法制备了一种轻质、高掺氮量(9.5 at%)的三维碳纳米纤维集流体.该集... 锂金属是未来二次电池实现高能量密度化的关键负极材料,然而,如何实现锂金属的均匀和无枝晶沉积是目前制约其实际应用的关键问题.本论文采用静电纺丝技术及高温碳化方法制备了一种轻质、高掺氮量(9.5 at%)的三维碳纳米纤维集流体.该集流体较低的密度能提升基于整个电池的能量密度,而且高掺氮量使其具备亲锂的特性,从而有效降低锂离子在其表面的初始形核过电位,得到均匀的金属锂种子层,实现后续金属锂的均匀沉积.这种三维结构有效抑制了锂枝晶的产生,降低了电池的极化,金属锂沉积/脱除测试中其库伦效率在循环250圈后仍可保持在98%以上.将其沉积金属锂后与LiFePO_4组装全电池,电池极化降低,在循环300圈后容量保持率可达82.4%,表现出很好的应用前景. 展开更多
关键词 碳纳米纤维 三维结构 负极材料 碳化方法 锂金属 集流体 氮量 轻质
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An air-stable and waterproof lithium metal anode enabled by wax composite packaging 被引量:7
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作者 yunbo zhang Wei Lv +9 位作者 Zhijia Huang Guangmin Zhou Yaqian Deng Jun zhang Chen zhang Boyu Hao Qi Qi Yan-Bing He Feiyu Kang Quan-Hong Yang 《Science Bulletin》 SCIE EI CAS CSCD 2019年第13期910-917,共8页
The reviving use of lithium metal anode(LMA)is one of the most promising ways to upgrade the energy density of lithium ion batteries.In the roadmap towards the real use,besides the formation of the dendrite,various ad... The reviving use of lithium metal anode(LMA)is one of the most promising ways to upgrade the energy density of lithium ion batteries.In the roadmap towards the real use,besides the formation of the dendrite,various adverse reactions due to the high activity of LMA when exposed to air or the electrolyte limit its practical applications.Learning from the packaging technology in electronic industry,we propose a wax-based coating compositing with the ion conducting poly(ethylene oxide)by a simple dip-coating technology and the prepared LMA is featured with an air-stable and waterproof surface.The LMA thus remains stable for 24 h in ambient air even with the relative humidity of 70% while retaining about85% its electrochemical capacity.More importantly,the LMA is accessible to water and when dipping in water,no obvious adverse reactions or capacity decay is observed.With the composite coating,a steady cycling performance for 500 h in symmetrical cells and a low capacity decay rate of 0.075% per cycle after 300 cycles in lithium-sulfur batteries assembled with the packaged anode have been achieved.This work demonstrates a very simple and effective LMA package technology which is easily scalable and is very promising for speeding up the industrialization of lithium-sulfur batteries and shows potentials for the large-scale production of air-sensitive electrode materials not limited to LMAs. 展开更多
关键词 LITHIUM metal anode Air-stable WATERPROOF DENDRITE LITHIUM sulfur battery
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Vertical Graphenes Grown on a Flexible Graphite Paper as an All-Carbon Current Collector towards Stable Li Deposition 被引量:3
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作者 Zhijia Huang Debin Kong +6 位作者 yunbo zhang Yaqian Deng Guangmin Zhou Chen zhang Feiyu Kang Wei Lv Quan-Hong Yang 《Research》 EI CAS 2020年第1期1222-1232,共11页
Lithium(Li)metal has been regarded as one of the most promising anode materials to meet the urgent requirements for the next-generation high-energy density batteries.However,the practical use of lithium metal anode is... Lithium(Li)metal has been regarded as one of the most promising anode materials to meet the urgent requirements for the next-generation high-energy density batteries.However,the practical use of lithium metal anode is hindered by the uncontrolled growth of Li dendrites,resulting in poor cycling stability and severe safety issues.Herein,vertical graphene(VG)film grown on graphite paper(GP)as an all-carbon current collector was utilized to regulate the uniform Li nucleation and suppress the growth of dendrites.The high surface area VG grown on GP not only reduces the local current density to the uniform electric field but also allows fast ion transport to homogenize the ion gradients,thus regulating the Li deposition to suppress the dendrite growth.The Li deposition can be further guided with the lithiation reaction between graphite paper and Li metal,which helps to increase lithiophilicity and reduce the Li nucleation barrier as well as the overpotential.As a result,the VG film-based anode demonstrates a stable cycling performance at a current density higher than 5mAcm^(-2)in half cells and a small hysteresis of 50mV at 1mAcm^(-2)in symmetric cells.This work provides an efficient strategy for the rational design of highly stable Li metal anodes. 展开更多
关键词 CYCLING VERTICAL HYSTERESIS
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Collisional dynamics of symmetric two-dimensional quantum droplets
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作者 Yanming Hu Yifan Fei +1 位作者 Xiao-Long Chen yunbo zhang 《Frontiers of physics》 SCIE CSCD 2022年第6期203-209,共7页
The collisional dynamics of two symmetric droplets with equal intraspecies scattering lengths and particle number density for each component is studied by solving the corresponding extended Gross–Pitaevskii equation ... The collisional dynamics of two symmetric droplets with equal intraspecies scattering lengths and particle number density for each component is studied by solving the corresponding extended Gross–Pitaevskii equation in two dimensions by including a logarithmic correction term in the usual contact interaction.We find the merging droplet after collision experiences a quadrupole oscillation in its shape and the oscillation period is found to be independent of the incidental momentum for small droplets.With increasing collision momentum the colliding droplets may separate into two,or even more,and finally into small pieces of droplets.For these dynamical phases we manage to present boundaries determined by the remnant particle number in the central area and the damped oscillation of the quadrupole mode.A stability peak for the existence of droplets emerges at the critical particle number Nc≃48 for the quasi-Gaussian and flat-top shapes of the droplets. 展开更多
关键词 ultracold atoms quantum droplets COLLISIONS
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