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Frontiers of Environmental Science & Engineering 2024年第5期18卷 127-136页

作者： Hao Zhang Huinan Li Pengyi Zhang Tingxia Hu Xianjie Wang State Key joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China beijing Key Laboratory for Indoor Air Quality Evaluation and Control Beijing100084China Midea Corporate research center Foshan528311China

Copper intercalated birnessite MnO_(2)(δ-MnO_(2))with weak crystallinity and high specific surface area(421 m^(2)/g)was synthesized by a one-pot redox method and investigated for low-temperature CO *** molar ratio of Cu/Mn was as high as 0.37,which greatly weakened the Mn-O bond and created a lot of low-temperature active oxygen *** situ DRIFTS revealed strong bonding of copper ions with ***-synthesized MnO_(2)-150Cu achieved 100%conversion of 250 ppm CO in normal air(3.1 ppm H_(2)O)even at−10°C under the weight-hourly space velocity(WHSV)of 150 L/(g·h).In addition,it showed high oxygen storage capacity to oxidize CO in inert *** the concurrent moisture in air significantly inhibited CO adsorption and its conversion at ambient temperature,MnO_(2)-150Cu could stably convert CO in 1.3%moisture air at 70°C owing to its great low-temperature activity and reduced competitive adsorption of water with increased *** study discovers the excellent low-temperature activity of weakly crystallized δ-MnO_(2) induced by high content intercalated copper ions.

关键词： CO oxidation Birnessite Interlayer copper Low-temperature Oxygen storage capacity

Data Component:An Innovative Framework for Information Value Metrics in the Digital Economy

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China Communications 2024年第5期21卷 17-35页

作者： Tao Xiaoming Wang Yu Peng Jieyang Zhao Yuelin Wang Yue Wang Youzheng Hu Chengsheng Lu Zhipeng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China beijing National research center for Information Science and Technology Beijing 100084China China Electronics Corporation Beijing 100084China

The increasing dependence on data highlights the need for a detailed understanding of its behavior,encompassing the challenges involved in processing and evaluating ***,current research lacks a comprehensive structure for measuring the worth of data elements,hindering effective navigation of the changing digital *** paper aims to fill this research gap by introducing the innovative concept of“data components.”It proposes a graphtheoretic representation model that presents a clear mathematical definition and demonstrates the superiority of data components over traditional processing ***,the paper introduces an information measurement model that provides a way to calculate the information entropy of data components and establish their increased informational *** paper also assesses the value of information,suggesting a pricing mechanism based on its *** conclusion,this paper establishes a robust framework for understanding and quantifying the value of implicit information in data,laying the groundwork for future research and practical applications.

关键词： data component data element data governance data science information theory

Subtraction of liposome signals in cryo-EM structural determination of protein-liposome complexes

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Chinese Physics B 2024年第8期33卷 569-577页

作者：李首卿李明王玉梅李雪明 Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Protein Sciences of Ministry of Education School of Life SciencesTsinghua UniversityBeijing 100084China State Key Laboratory of Membrane Biology School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua–Peking joint center for Life Sciences Beijing 100084China beijing Frontier research center for Biological Structure Beijing 100084China School of Life Sciences Tsinghua UniversityBeijing 100084China beijing Branch of Songshan Lake Materials Laboratory Beijing 100190China

Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong signal of liposomes under cryo-EM imaging conditions often interferes with the structural determination of the embedded membrane ***,we propose a liposome signal subtraction method based on single-particle two-dimensional(2D)classification average images,aimed at enhancing the reconstruction resolution of membrane *** analyzed the signal distribution characteristics of liposomes and proteins within the 2D classification average images of protein–liposome complexes in the frequency *** on this analysis,we designed a method to subtract the liposome signals from the original particle *** the subtraction,the accuracy of single-particle three-dimensional(3D)alignment was improved,enhancing the resolution of the final 3D *** demonstrated this method using a PIEZO1-proteoliposome dataset by improving the resolution of the PIEZO1 protein.

关键词： cryo-EM protein–liposome complexes liposome signal subtraction 2D classification averaging

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear Science and Techniques 2024年第5期35卷 74-84页

作者： Sheng-Jie Du Xiu-Xia Li Yang Tian Yuan-Yuan Liu Ke Jia Zhong-Zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan Li Zheng-Cao Li Sha-Sha Lv College of Nuclear Science and Technology joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment Key Laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China joint research center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

A phase separation-fortified bi-specific adaptor for conditional tumor killing

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Science China(Life Sciences) 2024年第7期67卷 1385-1397页

作者： Yuyan Liu Yuting Zhu Weifan Xu Pilong Li State Key Laboratory of Membrane Biology Frontier Research Center for Biological StructureTsinghua University-Peking University Joint Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China

A common approach in therapeutic protein development involves employing synthetic ligands with multivalency,enabling sophisticated control of signal *** the emerging concept of liquid-liquid phase separation(LLPS)and its ability to organize cell surface receptors into functional compartments,we herein have designed modular ligands with phase-separation modalities to engineer programmable interreceptor communications and precise control of signal pathways,thus inducing the rapid,potent,and specific apoptosis of tumor *** their simplicity,these“triggers”,named phase-separated Tumor Killers(hereafter referred to as psTK),are sufficient to yield interreceptor clustering of death receptors(represented by DR5)and tumor-associated receptors,with notable features:LLPSmediated robust high-order organization,well-choreographed conditional activation,and broad-spectrum capacity to potently induce apoptosis in tumor *** development of novel therapeutic proteins with phase-separation modalities showcases the power of spatially reorganizing signal *** approach facilitates the diversification of cell fate and holds promising potential for targeted therapies against challenging tumors.

关键词： phase separation therapeutic proteins receptor-ligand interactions DR5 tumor apoptosis

Targeting NAD Metabolism for the Therapy of Age-Related Neurodegenerative Diseases

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Neuroscience Bulletin 2024年第2期40卷 218-240页

作者： Feifei Li Chou Wu Gelin Wang School of Pharmaceutical Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China Tsinghua-Peking joint center for Life Sciences Tsinghua UniversityBeijing 100084China

As the aging population continues to grow rapidly, age-related diseases are becoming an increasing burden on the healthcare system and a major concern for the well-being of elderly individuals. While aging is an inevitable process for all humans, it can be slowed down and age-related diseases can be treated or alleviated. Nicotinamide adenine dinucleotide (NAD) is a critical coenzyme or cofactor that plays a central role in metabolism and is involved in various cellular processes including the maintenance of metabolic homeostasis, post-translational protein modifications, DNA repair, and immune responses. As individuals age, their NAD levels decline, and this decrease has been suggested to be a contributing factor to the development of numerous age-related diseases, such as cancer, diabetes, cardiovascular diseases, and neurodegenerative diseases. In pursuit of healthy aging, researchers have investigated approaches to boost or maintain NAD levels. Here, we provide an overview of NAD metabolism and the role of NAD in age-related diseases and summarize recent progress in the development of strategies that target NAD metabolism for the treatment of age-related diseases, particularly neurodegenerative diseases.

关键词： Ageing Neuroprotection NAD metabolism Therapeutic strategy Neurodegenerative diseases

Applying heteroatom co-doped carbon nanotube for manifesting high performance in the electrochemical reduction of aqueous nitrogen oxide by gold nanoparticles

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Nano research 2024年第3期17卷 1151-1164页

作者： Jane Chung Haibo Yin Rong Wang Yunlong Wang Junyang Zhang Yue Peng Joung Woo Han Seongyun Ryu Junhua Li State Key joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China EHS research center Samsung Electronics Co.Ltd.Gyeonggi-do 18448Republic of Korea

Electrochemical NO-to-NH_(3) under ambient conditions could be a viable alternative having advantages in terms of energy consumption and exhaust gas recycling of NO,replacing a traditional ammonia synthesis method of the Haber–Bosch *** synthesizing boron(B-)and nitrogen(N-)co-doped carbon nanotube(CNT)based gold(Au)catalysts,B-dopants elevate the conductivity of carbon nanotube by sp2 hybridization on graphene and implant B–N domains within the graphene layer,and result in facilitating the embedding amount of Au accompanied by high dispersibility with low particle *** density functional theory(DFT)calculations elucidate that the electron cloud transmitted from B-dopant to the active site of Au induces the Lewis acidic site,and the O-distal pathway occurs following a spontaneous *** of the electron-deficient B-doping area accompanied by N-defects and B–O edges retains the major valence state of Au as Au^(δ+),and suppresses hydrogen evolution reaction(HER)by repulsing the hindrance of H*.This record exhibits the highest faradaic efficiency(FE)of 94.7%,and NH_(3) yield rate of 1877.4μg·h^(-1)·mg_(cat)^(-1),which is the optimal yield over energy consumption in the field of the ambient reduction of aqueous NO.

关键词： boron heteroatom nitrogen defect gold nanoparticles valence states of gold electrochemical NO-to-NH3

Challenges and perspectives of air pollution control in China

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 9-16页

作者： Bin Zhao Shuxiao Wang Jiming Hao State Key joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

Air pollution is one of the most challenging environmental issues in the *** has achieved remarkable success in improving air quality in last decade as a result of aggressive air pollution control ***,the average fine particulate matter(PM2.5)concentration in China is still about six times of the World Health Organization(WHO)Global Air Quality Guidelines(AQG)and causing significant human health *** emission reductions of multiple air pollutants are required for China to achieve the *** we identify the major challenges in future air quality improvement and propose corresponding control *** main challenges include the persistently high health risk attributed to PM2.5 pollution,the excessively loose air quality standards,and coordinated control of air pollution,greenhouse gases(GHGs)emissions and emerging *** further improve air quality and protect human health,a health-oriented air pollution control strategy shall be implemented by tightening the air quality standards as well as optimizing emission reduction pathways based on the health risks of various *** the meantime,an“oneatmosphere”concept shall be adopted to strengthen the synergistic control of air pollutants and GHGs and the control of non-combustion sources and emerging pollutants shall be enhanced.

关键词： Air pollution China Health impact Air quality standards GHGs Emerging pollutants

Influence of layer thickness on formation quality,microstructure,mechanical properties,and corrosion resistance of WE43 magnesium alloy fabricated by laser powder bed fusion

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Journal of Magnesium and Alloys 2024年第4期12卷 1367-1385页

作者： Bangzhao Yin Jinge Liu Bo Peng Mengran Zhou Bingchuan Liu Xiaolin Ma Caimei Wang Peng Wen Yun Tian Yufeng Zheng State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Institute for Precision Medicine Tsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China beijing AKEC Medical Co. Ltd.Beijing 102200China School of Materials Science and Engineering Peking UniversityBeijing 100871China Engineering research center of Bone and joint Precision Medicine Ministry of EducationBeijing 100191China

Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical *** thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg *** this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were *** required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous *** tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy *** thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the *** the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy *** increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain *** the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural *** effect of layer thickness on the compressive properties of porous scaffolds was ***,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases.

关键词： Magnesium alloy WE43 Laser powder bed fusion Layer thickness Process optimization

Underestimated benefits of NO_(x) control in reducing SNA and O_(3) based on missing heterogeneous HONO sources

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 57-67页

作者： Shuping Zhang Haotian Zheng Jun Liu Yao Shi Tianzeng Chen Chaoyang Xue Fenfen Zhang Yueqi Jiang Xiangping Zhang Shovan Kumar Sahu Biwu Chu Jia Xing State Key joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China China Academy of Civil Aviation Science and Technology Beijing 100028China State Key joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Yellow River Institute of Hydraulic research Zhengzhou 450003China Centre for Climate research Singapore Meteorological Service SingaporeSingapore 537054Singapore

Substantial NO_(x) emission mitigation is crucial for the synergistic reduction of particulate matter and ozone(O_(3))pollution in *** traditional air quality model does not consider heterogeneous HONO chemistry,leading to uncertainties in estimating the benefits of NO_(x) *** studies have shown that the parameterization of heterogeneous HONO formation increases both the simulated value of sulfate–nitrate–ammonium(SNA)and that of O_(3),thus adding the heterogeneous reactions of HONO into air quality models inevitably leads to changes in the estimated benefits of NO_(x) *** we investigated the changes in SNA and O_(3)concentrations from NO_(x) emission reduction before and after adding heterogeneous HONO reactions in the Community Multi-Scale Air Quality(CMAQ)*** heterogeneous HONO reactions in the simulation improved the benefits of NO_(x) reduction in terms of SNA control in *** 80%NO_(x) reduction,the reduction in SNA increased from 36.9%without considering heterogeneous HONO reactions to 42.8%with heterogeneous HONO *** reduction in the maximum daily 8h average(MDA8)O_(3)in summer caused by NO_(x) reduction increased slightly from 4.7%to 5.2%after adding heterogeneous HONO *** results in this study highlight the enhanced effectiveness of NO_(x) controls for the reduction of SNA and O_(3)after considering heterogeneous HONO formation in a complex chemical ambient,demonstrating the importance of NO_(x) controls in reducing PM2.5 and O_(3)pollution in China.

关键词： Heterogeneous HONO NO_(x) reduction PM_(2.5) O_(3)