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双层单原子催化剂用于促进高活性和选择性电催化硝酸盐还原制氨

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物理化学学报 2024年第6期40卷 60-62页

作者：于镜坤雍雪曹昂卢思宇郑州大学化学学院绿色催化中心郑州450001 Department of Chemistry University of SheffieldSheffieldS37HFUK Department of Physics Technical University of DenmarkKongens Lyngby 2800Denmar

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSA... 详细信息

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

关键词：硝酸盐还原第一性原理计算单原子催化剂双层单原子催化剂轴向轨道杂化

青藏高原及其周边三叠纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1171-1210页

作者：武桂春纪占胜 Gary GLASH 曾庆高姚建新中国地质科学院地质研究所自然资源部地层与古生物重点实验室北京100037 中国地质科学院自然资源部深地科学与探测技术实验室北京100094 Department of Geology and Environmental Sciences State University of New York-FredoniaFredoniaNY 14063USA 西藏自治区地质矿产勘察开发局拉萨850010

青藏高原三叠纪古生物化石丰富,目前已建立了以菊石、牙形类、双壳类、腕足类和放射虫化石为主的海相生物序列以及以孢粉类化石为主的陆相生物序列,为青藏高原三叠纪年代地层划分对比提供了生物标尺.青藏高原在三叠纪整体处于海洋沉积区... 详细信息

青藏高原三叠纪古生物化石丰富,目前已建立了以菊石、牙形类、双壳类、腕足类和放射虫化石为主的海相生物序列以及以孢粉类化石为主的陆相生物序列,为青藏高原三叠纪年代地层划分对比提供了生物标尺.青藏高原在三叠纪整体处于海洋沉积区,海相三叠系发育,主要沉积类型有滨浅海相碎屑岩、浅海台地相碳酸盐岩、半深海斜坡-深海相碎屑岩、硅质岩、海陆过渡相含煤碎屑岩、滨浅海或陆相火山碎屑岩.青藏高原各个地层区的沉积地层序列在垂向上明显分为4个阶段:(1)早三叠世初期广泛接受海侵,发育台地相碳酸盐岩和滨浅海相碎屑岩沉积;(2)中三叠世拉丁期至晚三叠世卡尼期海侵规模最大,与早三叠世相比,沉积相整体变深,发育半深海斜坡-深海相薄层碳酸盐岩、细碎屑岩、硅质岩沉积,部分地区岩浆活动强烈;(3)晚三叠世诺利期海退,沉积相整体变浅,大面积发育台地相碳酸盐岩沉积和滨浅海碎屑岩沉积,在秦-祁-昆一带多表现为陆相地层沉积或陆相剥蚀区;(4)瑞替期持续海退,发育滨浅海碎屑岩或海陆过渡相含煤碎屑岩沉积.根据沉积地层的横向展布和垂向变化,本文对青藏高原三叠纪的沉积古地理按早三叠世、中三叠世-晚三叠世卡尼期、晚三叠世诺利期和晚三叠世瑞替期4个时期进行了描述.整体上,青藏高原在三叠纪是以印度河-雅鲁藏布江缝合带为拉张中心,沉积相向南、北两侧由深变浅,形成了南部冈瓦纳古陆被动边缘沉积体系和北部欧亚古陆被动大陆边缘沉积体系.班公湖-怒江缝合带与南侧的冈底斯地块(或拉萨地块)和北侧的南羌塘地块在沉积特征上比较一致,不是裂解拉张中心.古生物区系研究同样显示印度河-雅鲁藏布江缝合带在三叠纪时期是一个重要的古生物地理区系分界线,班公湖-怒江缝合带在该时期则不具有古生物地理区系分隔的意义.三叠纪时期是潘吉亚超大陆(Pangea)裂解的高峰期,该事件在青藏高原的主要响应是早、中三叠世沿印度河-雅鲁藏布江缝合带发生伸展裂解.印支运动在青藏高原主要表现为晚三叠世地壳抬升引起的沉积相变,在秦-祁-昆一带表现为海相沉积变为陆相沉积或陆相剥蚀区,而在冈底斯至南羌塘的广大地区,表现为台地相碳酸盐岩变为滨浅海相碎屑岩或海陆过渡相含煤碎屑岩.

关键词：青藏高原三叠系生物地层岩石地层古生物区系沉积古地理

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怀化市现代畜牧业现状及发展建议

中国畜禽种业 2024年第7期20卷 64-70页

作者：聂昂姚亚铃何凌云李科湖南省怀化市畜牧水产事务中心湖南怀化418000 湖南省怀化市农业综合行政执法支队湖南怀化418000

近年来,怀化市多措并举推动畜牧业高质量发展,在稳产保供、产业链条发展、龙头企业带动、品牌打造、养殖方式升级、种业品质提升等方面取得了重大成效。为进一步促进怀化市现代畜牧业稳定健康发展,该文在调研的基础上,剖析了畜牧业发展... 详细信息

近年来,怀化市多措并举推动畜牧业高质量发展,在稳产保供、产业链条发展、龙头企业带动、品牌打造、养殖方式升级、种业品质提升等方面取得了重大成效。为进一步促进怀化市现代畜牧业稳定健康发展,该文在调研的基础上,剖析了畜牧业发展中存在的现代化程度不高、特色产业优势不突出、畜牧产业链条不完整、自主品牌培育不够、科技创新能力不足、市场价格周期性波动等问题,提出加快畜牧业现代化建设、培育畜禽优势特色产业、推进畜禽全产业链发展、加快畜牧业品牌建设、构建现代科技服务体系、发挥职能部门调控作用等发展建议。

关键词：现代畜牧业现状发展建议怀化市

Advances in cost-effective integrated spectrometers

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Light(Science & Applications) 2022年第7期11卷 1379-1396页

作者： ang Li Chunhui yao Junfei Xia Huijie Wang Qixiang Cheng Richard Penty Yeshaiahu Fainman Shilong Pan Key Laboratory of Radar Imaging and Microwave Photonics Ministry of EducationNanjing University of Aeronautics and AstronauticsNanjing 210016China Litin Technology XuzhouJiangsuChina Department of Engineering University of Cambridge9 JJ Thomson AvenueCambridge CB30FAUK Colllege of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Electrical and Computer Engineering University of California at San DiegoLa JollaCAUSA

The proliferation of Internet-of-Things has promoted a wide variety of emerging applications that require compact,lightweight,and low-cost optical *** substantial progresses have been made in the miniaturization of spectrometers,most of them are with a major focus on the technical side but tend to feature a lower technology readiness level for *** importantly,in spite of the advancement in miniaturized spectrometers,their performance and the metrics of real-life applications have seldomly been connected but are highly *** review paper shows the market trend for chip-scale spectrometers and analyzes the key metrics that are required to adopt miniaturized spectrometers in real-life *** progress addressing the challenges of miniaturization of spectrometers is summarized,paying a special attention to the CMOS-compatible fabrication platform that shows a clear pathway to massive *** for ways forward are also presented.

关键词： cost summarized spite

Gut microbiota alteration and modulation in hepatitis B virus-related fibrosis and complications:Molecular mechanisms and therapeutic inventions

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World Journal of Gastroenterology 2022年第28期28卷 3555-3572页

作者： yao-Guang Li zu-Jiang Yu ang Li zhi-Gang Ren Department of Infectious Diseases The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Gene Hospital of Henan Province Precision Medicine CenterThe First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Jinan Microecological Biomedicine Shandong Laboratory Jinan 250000Shandong ProvinceChina

Hepatitis B virus(HBV)has posed a threat to public health,mainly resulting in liver *** long-term accumulation of extracellular matrix,patients with chronic hepatitis B are at high risk of developing into liver fibrosis and cirrhosis and even life-threatening hepatic *** occurrence of complications such as spontaneous bacterial peritonitis and hepatic encephalopathy greatly increases disability and *** deeper understanding of the bidirectional interaction between the liver and the gut(gut-liver axis),there is a growing consensus that the human health closely relates to the gut *** by animal and human studies,the gut microbiota alters as the HBV-related liver fibrosis initials and progresses,characterized as the decrease of the ratio between“good”and“potentially pathogenic”*** the primary disease is controlled via antiviral treatment,the gut microbiota dysfunction tends to be ***,the recovery of gut microbiota can promote the regression of liver *** strategies targeted on gut microbiota(rifaximin,probiotics,engineered probiotics and fecal microbiota transplantation)have been applied to animal models and patients,obtaining satisfactory results.

关键词： Hepatitis B virus Gut microbiota Liver fibrosis Liver cirrhosis Hepatic encephalopathy Fecal microbiota transplantation

Low-dose immune tolerance induction for severe hemophilia A inhibitor patients:Immunosuppressants are generally not necessary for inhibitor-titer below 200 BU/mL

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Pediatric Investigation 2024年第2期8卷 91-100页

作者： zhengping Li Jie Sun zekun Li zhenping Chen Guoqing Liu Wanru yao Xiaoling Cheng Gang Li Yingzi zhen Di Ai yaohan zhou Qianqian Mao Man-Chiu Poon Runhui Wu Hemophilia Comprehensive Care Center Hematology DepartmentHematology CenterBeijing Key Laboratory of Pediatric Hematology-OncologyKey Laboratory of Major Diseases in ChildrenNational Key Discipline of Pediatrics(Capital Medical University)Ministry of EducationBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Hematologic Disease Laboratory Hematology DepartmentHematology CenterBeijing Key Laboratory of Pediatric Hematology-OncologyKey Laboratory of Major Diseases in ChildrenNational Key Discipline of Pediatrics(Capital Medical University)Ministry of EducationBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Pharmacy Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Departments of Medicine Pediatrics and OncologyUniversity of Calgary Cumming School of MedicineCalgaryCanada

Importance:It remained unclear that the efficacy comparison between low-dose immune tolerance induction(LD-ITI)incorporating immunosuppressants(IS)when severe hemophilia A(SHA)patients had inhibitor-titer≥200 Bethesda Units(BU)/mL(LD-ITI-IS^(200) regimen)and LD-ITI combining with IS when SHA patients had inhibitor-titer≥40 BU/mL(LD-ITI-IS^(40) regimen).Objective:To compare the efficacy of the LD-ITI-IS^(200) regimen with that of the LD-ITI-IS^(40) regimen for SHA patients with high-titer ***:A prospective cohort study on patients receiving LD-ITI-IS^(200) compared to those receiving LD-ITI-IS^(40) from January 2021 to December *** received LD-ITI[FVIII 50 IU/kg every other day].IS(rituximab+prednisone)was added when peak inhibitor tier≥200 BU/mL in the LD-ITI-IS^(200) regimen and≥40 BU/mL in the LD-ITI-IS^(40) *** is defined as a negative inhibitor plus FVIII recovery≥66%of the ***:We enrolled 30 patients on LD-ITI-IS^(200) and 64 patients on LD-ITI-IS^(40),with similar baseline clinical characteristics.A lower IS-use rate was discovered in the LD-ITI-IS^(200) regimen compared to the LD-ITI-IS^(40) regimen(30.0%vs.62.5%).The two regimens(LD-ITI-IS^(200) ***-ITI-IS^(40))had similar success rate(70.0%vs.79.7%),median time to success(9.4 vs.10.6 months),and annualized bleeding rate during ITI(3.7 vs.2.8).The cost to success was lower for LD-ITI-IS^(200) than for LD-ITI-IS^(40)(2107 vs.3256 US Dollar/kg).Among patients with peak inhibitor-titer 40-199 BU/mL,10 non-IS-using(on LD-ITI-IS^(200) regimen)and 28 IS-using(on LD-ITI-IS^(40) regimen)had similar success rates(70.0%vs.78.6%)and time to success(9.0 vs.8.8 months).Interpretation:In LD-ITI,IS are not necessary for inhibitor titer<200 BU/mL.

关键词： Hemophilia A High-titer inhibitor Immune tolerance induction Immunosuppressant Low-dose

Synthesis of the tetracyclic core of chlorospermines

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Chinese Chemical Letters 2015年第3期26卷 272-276页

作者： Ming Wan Ming yao Jun-Yu Gong Peng Yang Hua Liu ang Li School of Pharmacy Jiangxi University of Traditional Chinese Medicine State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences

Chlorospermines A and B are biologically interesting acridone natural products and recently isolated from Glycosmis *** report here a convergent approach to construct the tetracyclic core of the natural *** two fragments are assembled together through Sonogashira coupling,and a cis-triene intermediate was prepared by using hydrosilylation/desilylation.A 6p-electrocyclization/aromatization sequence served as the key step of the synthesis,which formed the tetrasubstituted arene motif in one pot.

关键词： convergent sequentially steps assembled biologically filtered arene motif equiv latter

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拮抗灰葡萄孢菌乳酸菌的筛选与鉴定

工业微生物 2024年第2期54卷 158-160页

作者：刘昂周芊芊董柏余姚秋萍冯瑶朱德全贵州民族大学民族医药院贵州贵阳550025 贵州民族大学贵州省少数民族医药资源开发与利用国家民委重点实验室贵州贵阳550025

灰葡萄孢菌(Botrytis cinerea)是导致果蔬腐败的主要病原菌之一。乳酸菌因为安全、无毒且具有一定的抗菌作用,在抑制果蔬腐败病原菌方面具有一定的潜在价值。鉴于此,文章期望从发酵食品和常见水果表面分离并筛选出抑制灰葡萄孢菌活性的... 详细信息

灰葡萄孢菌(Botrytis cinerea)是导致果蔬腐败的主要病原菌之一。乳酸菌因为安全、无毒且具有一定的抗菌作用,在抑制果蔬腐败病原菌方面具有一定的潜在价值。鉴于此,文章期望从发酵食品和常见水果表面分离并筛选出抑制灰葡萄孢菌活性的乳酸菌,结果发现有10株乳酸菌对灰葡萄孢具有抑菌活性。经鉴定,3株(Jz a1、MJ a2、PS b1)为Limosilac tobacillus fe rme ntum,2株(zLJ、MDF b)为Lactobac illus pentosus,MHT b为Lactobacillus ac idophilus,4株(SCb1、MJ a、MDF a、MHT a1)还有待进一步鉴定。文章为开发果蔬生物保鲜剂提供了实践基础与理论支撑。

关键词：果蔬腐败菌乳酸菌灰葡萄孢菌拮抗

“目标—行动—反馈”框架下z县脱贫攻坚到乡村振兴的衔接路径——基于产业发展的视角

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新疆大学学报（哲学社会科学版） 2024年第4期52卷 93-102页

作者：麦迪娜·吐逊江杨瑶中国人民大学公共管理学院北京100872

脱贫攻坚到乡村振兴的有效衔接是建成社会主义现代化新农村,实现中国式现代化的关键所在,然而,该问题在目前阶段仍然面临着理论与实践的挑战。基于解答疑问和应对挑战的内在逻辑驱动,文章首先梳理了从脱贫攻坚转向乡村振兴的宏观政策背... 详细信息

脱贫攻坚到乡村振兴的有效衔接是建成社会主义现代化新农村,实现中国式现代化的关键所在,然而,该问题在目前阶段仍然面临着理论与实践的挑战。基于解答疑问和应对挑战的内在逻辑驱动,文章首先梳理了从脱贫攻坚转向乡村振兴的宏观政策背景,揭示了有效衔接的重要性和必要性;其次在“目标—过程—反馈”的分析框架下,从地方政策目标接续、产业发展行动变革、成果反馈机制构建三个方面对山西省z县的案例资料展开分析,以期更全面地呈现基层实践中的衔接路径和基层治理样态,尝试为我国乡村振兴提供破解难题的关键路径参考。

关键词：脱贫攻坚乡村振兴目标—行动—反馈产业发展衔接路径