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Isotopic characteristics and source analysis of atmospheric ammonia during agricultural periods in the Xichuan area of the Danjiangkou Reservoir

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Journal of Environmental Sciences 2024年第2期136卷 460-469页

作者： Xiaoshu Chen Tongqian Zhao Chunyan Xiao Xiaoming Guo feihong Chen Institute of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000China

Nitrogen deposition is an important means of exogenous nitrogen input in reservoir *** activities around the reservoir lead to a sharp increase in the concentration of ammonia in the atmosphere,which poses a threat to the reservoir water *** the contribution of agricultural ammonia release to atmospheric NH_(x)(gaseous NH_(3)and particulate NH_(4)^(+)),in the reservoir area can provide a theoretical foundation for local reactive nitrogen *** collected atmospheric NH_(3)and NH_(4)^(+)samples during the agricultural periods and analyzed the isotopic characteristics of atmospheric NH_(x)and the contribution rates of different ammonia sources in the Xichuan area of the Danjiangkou *** results showed that the initialδ~(15)N values of NH_(3)(-30.0‰to–7.2‰)and particulate NH_(4)^(+)(–33‰to+4.9‰for finer and coarser particles,respectively)are different,and their contribution ratios from dissimilar ammonia sources are also different,among which NH_(4)^(+)is more susceptible to meteorological ***,since the atmospheric NH_(x)in the Xichuan area is mainly gaseous NH_(3),the final sources of atmospheric ammonia nitrogen source depend on gaseous NH_(3).Agricultural sources(59%-74%)were the main NH_(3)sources in this *** them,the fertilizer use emission was dominant;it had the highest contribution rate in summer during the agricultural period and a more prominent impact in areas with less human *** regulation of the application of high-ammonia releasing fertilizer,especially during the agricultural period in summer,is an effective way to reduce the threat of atmospheric ammonia to water health.

关键词： Danjiangkou reservoir Atmospheric ammonia nitrogen Isotope Ammonia source analysis Agricultural sources

Intermittent energy restriction altered the fecal metabolites in Chinese and Pakistani individuals driven by shifts in diet and gut microbiota

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Intermittent energy restriction altered the fecal metabolite...

A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability

中国营养学会第十五届全国营养科学大会

作者： Siyu Chen Ikram Ali Tingyu Yang feihong ren Xiaodan Huang 兰州大学公共卫生学院

Intermittent energy restriction(IER) defined as periods of energy restriction interspersed with normal energy intake. As a common alternative form of intermittent energy restriction, Ramadan fasting is a religious practice where practitioners of the Muslim faith undergo a yearly ritual in which no food or beverages are consumed between sunrise to sunset for 29-30 days. Our previous finding has demonstrated that Ramadan fasting could leads to shifts in human gut microbiota structured by changing dietary composition. Together with gut microbiota, metabolites also jointly participate the gut function in nutritive, immunologic, and protective in host metabolism. However, limited human studies have been conducted to characterize whether diet-related behaviors, such as fasting(intermittent energy restriction) can influence fecal metabolites, given consideration of ethnic difference. In this study, we aim to study the changes of metabolites in fecal of two ethnic groups before and after fasting by metabolomics, search for potential biomarkers and related metabolic pathways, and thus figure out whether Ramadan fasting altered the metabolites in Chinese and Pakistani individuals with consideration of diet changes. The study will provide new ideas for potential influence of intermittent energy restriction on human health. Methods 34 healthy adult participants, living in the city of Lanzhou and distributed across two ethnic groups(16 Chinese and 18 Pakistani) were recruited in this study. B survey and fecal samples were collected from the two groups before and after Ramadan fasting. LC-MS metabolomics data analysis was used to detect the metabolites from fecal samples. Unsupervised principle component analysis and(orthogonal) partial least-squares-discriminant analysis were employed to identify differential metabolites between different groups. Software as Compound Discoverer3.1 and R were used to analysis metabolomics and metagenomic data before and after fasting in different

关键词： Ethnicity Ramadan fasting Dietary habit Fecal metabolomics LC-MS

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Defence Technology（防务技术） 2024年第4期34卷 258-268页

作者： feihong Lin Zhongming Yan Ping Wang Yu Wang Hongcheng Zhou Haoran Lu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle Ministry of EducationChengdu 610031China China Academy of Launch Vehicle Technology Beijing 100076China

An ultrawideband reflectionless metamaterial absorber(MA)is proposed by replacing the metallic ground with the complementary split-ring resonator(CSRR)*** proposed MA exhibits-10 d B reflectivity spectrum from 1 GHz to 20 GHz,which maintains more than 90%absorption from 1.5 GHz to20 ***,it achieves angle stability for TE and TM polarization at oblique incident angles up to 40°and 65°,*** achieve broadband absorption spectrum,we have adopted a single-layer high-impedance surface(HIS)loaded with a double-layer magnetic material(MM)*** further realize the RCS reduction into a lower frequency range,we have employed the scattering cancellation technology into the traditional metallic ***,we have fabricated a sample exhibiting the 10 d B RCS reduction from 1 GHz to 20 GHz with a thickness of 10 *** and simulation results confirm that the proposed MA exhibits excellent comprehensive performance,making it suitable for many practical applications.

关键词： Metamaterial absorber(MA) Magnetic material(MM) High-impedance surface(HIS) Scattering cancellation technology Ultrawideband Wide-angular stable

Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

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Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： Qian Yang Kun Wang Meiling Zhang feihong Du Jiayang Li Chen Zheng Jinyang Li School of Chemistry Southwest Jiaotong University Yibin Institute of Southwest Jiaotong University

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Electrocatalysis Guest species Intercalation chemistry Layered materials

Frequent Gain and Loss of Resistance against Tobacco Mosaic Virus in Nicotiana Species

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Molecular Plant 2015年第12期8卷 1813-1815页

作者： Yuan, Xinjie Yan, Chenghuan Wu, Zhujun ren, feihong Zhang, Hui Baker, Barbara Chen, Jiongjiong Kuang, Hanhui Huazhong Agr Univ Key Lab Hort Plant Biol Minist EducMOAColl Hort & Forestry Sci Key Lab Hort Crop Biol & Genet Improvement Cent R Wuhan 430070 Peoples R China Univ Calif Berkeley Dept Plant & Microbial Biol Berkeley CA 94720 USA USDA ARS Ctr Plant Gene Express Albany CA 94710 USA

Dear Editor Resistance （R） genes represent one of the most divergent gene families in plants. Novel resistance function might arise through point mutations or sequence exchanges between paralogues （Kuang et al., 20... 详细信息

关键词： EVOLUTION FAMILY GENES

Traceless photodegradable polymer cocoons for universal protein delivery and light-controlled gene editing

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Science China Chemistry 2024年第2期67卷 664-676页

作者： Huaibin Yu Meron Tsegay Kifle Lili Chen feihong Xiong Yan Zhang Shangbang Gao Wei Hou Shuliang Chen Weining Zhao Yuzhou Wu Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Hubei Key Laboratory of Bioinorganic Chemistry&Materia MedicaKey Laboratory of Material Chemistry for Energy Conversion and StorageMinistry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and Technology(HUST)Wuhan430074China Zhengzhou Research Institute Harbin Institute of TechnologyZhengzhou450000China College of Life Science and Technology Huazhong University of Science and Technology(HUST)Wuhan430074China Institute of Medical Virology School of Basic Medical SciencesWuhan UniversityWuhan430071China College of Pharmacy Shenzhen Technology UniversityShenzhen518118China

Polymer conjugation was found highly valuable in clinic to improve the bioavailability of protein ***,it is still a tremendous challenge to achieve a complete release of original proteins from the conjugated hybrid under external stimulus to recover active proteins in the targeted ***,we report a general light-controlled protein delivery methodology by weaving a photodegradable polymer cocoon around proteins,which could reliably protect them from degradation in the dark while efficiently releasing them under illumination without any residual *** surface charge of the polymer shell is easily tunable to facilitate efficient cell *** versatility of this strategy is demonstrated by the delivery of the Cas9/sg RNA complex that realized light-controlled gene editing both in vitro and in vivo,and such repertoire is of particular value in regard to minimizing the off-target toxicity of CRISPR-Cas9-based gene therapy.

关键词： photodegradable polymer-protein conjugate protein delivery light control gene editing

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改善颗粒物污染的道路绿地植被屏障研究进展

生态学报 2022年第13期42卷 5177-5186页

作者：任飞虹白骅邱兆文田顺长安大学建筑学院西安710061 长安大学汽车学院西安710064

减少道路环境的颗粒物污染对通勤者的健康至关重要。道路绿地在交通排放和邻近区域之间形成屏障,但这种植被屏障是否可以有效消减局部颗粒物污染仍然需要深入研究和探讨。结合现有研究成果,阐述了植被对颗粒物污染的影响途径;分析了街... 详细信息

减少道路环境的颗粒物污染对通勤者的健康至关重要。道路绿地在交通排放和邻近区域之间形成屏障,但这种植被屏障是否可以有效消减局部颗粒物污染仍然需要深入研究和探讨。结合现有研究成果,阐述了植被对颗粒物污染的影响途径;分析了街道峡谷和开放道路两种典型城市道路环境中,植被组成及群落结构设计的关键特征对颗粒物分布和扩散的影响;总结了有利于消减颗粒物浓度的植被单株性状和叶片微形态;探讨了影响颗粒物浓度的其他因子的耦合作用;针对不同道路环境提出了有效的植被屏障设计建议,并指出了植被群落设计和叶片微形态方面的研究趋势,以期优化道路植被规划,改善路域空气质量。

关键词：颗粒物污染开放道路街道峡谷植被屏障叶片微形态

A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

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Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

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Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

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