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Construction and nanotribological study of a glassy covalent organic network on surface

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Nano Research 2022年第5期15卷 4682-4686页

作者： Guangyuan Feng Qingqing Luo Mengqi Li yaru song Yongtao Shen Shengbin Lei Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China School of Materials Science and Engineering Tianjin UniversityTianjin 300072China

Unraveling the nature of complex condensed matter systems is of paramount importance in a variety of fields such as pharmacology and materials *** we report the synthesis,by the dynamic covalent chemistry(DCC),of a robust,continuous,and low-defect glassy covalent organic network(GCON).The direct imaging of the molecular structure clearly shows the amorphous nature of GCONs,which consists with the competing(nano)crystallite model,not Zachariasen continuous random networks(Z-CRN).Remarkably,the microscopic friction properties were measured on GCONs by atomic force microscopy(AFM),and the GCONs showed lower friction force in comparison with crystalline covalent organic frameworks(COFs).

关键词： atomic force microscopy glassy covalent organic networks(GcoN) nanotribological competing(nano)crystallite model scanningtunnelingmicroscopy

2D-polyimide film sensitized monolayer MoS_(2) phototransistor enabled near-infrared photodetection

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Nano Research 2022年第9期15卷 8428-8434页

作者： Qingqing Luo Guangyuan Feng yaru song Enbing Zhang Jiangyan Yuan Dejuan Fa Qisheng Sun Shengbin Lei Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)-based heterostructures open the door to fabricate various promising hybrid photodetectors,while it is still a challenge to achieve excellent and stable near-infrared(NIR)***,a MoS_(2)–2DPI(2D-polyimide(2DPI))heterojunction-based phototransistor(HPT)was ***-infrared photodetection with excellent performance has been *** HPT exhibited a photoresponsivity of 390.5 A/W,a specific detectivity of 5.10×10^(12)Jones,a photogain 1.04×10^(5),and a photoresponse rise and decay time of 400 and 430 ms(λ=900 nm,P=16.2μW/cm^(2)),*** also shows a broadband wavelength response from 405 to 1,020 *** superior performance could be attributed to the strong near-infrared absorption and the type-II(staggered)band alignment which ensures efficient charge transfer from 2DPI to MoS_(2).The face-to-face spatial configuration of MoS_(2)–2DPI heterostructures ensures efficient transfer of photoinduced carriers through the interface,electron and holes can be separated due to the large band *** work presents a significant step for the manipulation of high-performance NIR photodetector of twodimensional covalent organic polymer-sensitized monolayer TMDCs.

关键词： MoS_(2) polyimide film heterojunction near-infrared phototransistor

不同提取方法山苍子油的化学成分与抗氧化活性分析

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林业科学 2015年第3期51卷 124-131页

作者：李芳 yaru song Howard Holness Kevin O’Shea 福建农林大学植物保护学院福州350002 佛罗里达国际大学化学与生物化学系佛罗里达州迈阿密33199

【目的】比较不同提取方法对山苍子油提取效率与抗氧化活性的影响,通过GC-MS分析,研究山苍子油成分构成与抗氧化活性的内在关联,分析山苍子油抗氧化活性的主要物质基础。【方法】采用液液萃取（分别加以超声波与磁化辅助处理）、二氧化... 详细信息

【目的】比较不同提取方法对山苍子油提取效率与抗氧化活性的影响,通过GC-MS分析,研究山苍子油成分构成与抗氧化活性的内在关联,分析山苍子油抗氧化活性的主要物质基础。【方法】采用液液萃取（分别加以超声波与磁化辅助处理）、二氧化碳超临界萃取以及水蒸气蒸馏法提取山苍子油,DPPH法比较不同提取方式对山苍子油抗氧化活力的影响,GC-MS分析山苍子油的主要成分,并以1,4-二溴苯为内标,采用面积归化法解析主要成分的相对含量。【结果】山苍子油具有显著的抗氧化活性。液液萃取法的提取效率与山苍子油抗氧化活性最高,超声波辅助处理油得率最高,为26.3%,磁化辅助处理抗氧化活性最优,达到31.22 mg·mL^-1（IC50）,二氧化碳超临界萃取法次之,抗氧化活性为56.95 mg·mL^-1（IC50）,水蒸气蒸馏法抗氧化活性最弱,为64.95 mg·mL^-1（IC50）;GC-MS分析检测出122种以上的化合物,包括12种脂肪酸,16种萜烯,18种含氧萜烯以及其他微量化合物包括烯烃、醇、酮类与烷烃等。GC-MS分析结果表明：山苍子干果主要成分为饱和脂肪酸（月桂酸等）、不饱和脂肪酸（9,12-十八碳二烯酸、9-十八碳烯酸等）以及α蒎烯、β蒎烯、柠檬烯等萜烯、氧化萜烯类物质。液液萃取法得到的山苍子油脂肪酸含量（53.51%-66.61%）明显高于二氧化碳超临界萃取（17.64%）与水蒸气蒸馏法（8.1%）,而二氧化碳超临界萃取与水蒸气蒸馏法得到的萜烯、氧化萜烯类含量分别达到29.37%和17.69%,明显高于液液萃取法（6.49%-9.75%）。【结论】磁化辅助处理有利于抗氧化活性物质的提取,且不饱和脂肪酸的含量最高;超声波辅助处理可以提升油的得率;水蒸气蒸馏法和超临界流体萃取法更有利于萜烯类化合物的获取;联系到水蒸气蒸馏法得到的山苍子油富含萜烯化合物却显示较低的抗氧化活性（64.95 mg·mL^-1）,色谱级的柠檬醛抗氧化活性最低（74.33 mg·mL^-1）,因此推测脂肪酸成分（特别是不饱和脂肪酸）是山苍子油抗氧化活性的主要物质基础。

关键词：山苍子 GC-MS 提取抗氧化活性

Comprehensive genomic analysis of early and late-onset hepatocellular carcinoma

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Genes & Diseases 2024年第4期11卷 77-81页

作者： Jialin Yang Chao Chen song Wang yaru Zhang Jiaohui Pang Yajun Wang Qiuxiang Ou Hao Jiang Juying Liu Department of Radiation Oncology Sichuan Cancer Hospital&InstituteSichuan Cancer CenterSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan 610041China Jinling Hospital Department of OncologyNanjing Medical UniversityNanjingJiangsu 210002China Geneseeq Research Institute Nanjing Geneseeq Technology Inc.NanjingJiangsu 210000China Department of Oncology Haian Hospital of Traditional Chinese MedicineHaianJiangsu 226600China Interventional Therapy Department Jiangsu Cancer Hospital&Jiangsu Institute of Cancer Research&The Affiliated Cancer Hospital of Nanjing Medical UniversityNanjingJiangsu 210009China

Hepatocellular carcinoma(HCC)is the major histologic type of primary liver cancer,accounting for approximately 75%of liver cancer cases.'Despite many advancements in its treatment,the prognosis and drug response of HCC patients are ***,there is an unmet clinical need to explore genomic aberrations underlying early-and lateonset HcC,which might facilitate drug discovery and provide personalized biomarker-driven treatment options for these patients.

关键词： patients prognosis cancer

Room temperature spontaneous surface condensation of boronic acids observed by scanning tunneling microscopy

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中国化学快报:英文版 2023年第8期34卷 425-428页

作者： Qiu Liang Guangyuan Feng Hongzhen Ni yaru song Xinyu Zhang Shengbin Lei Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of Science&Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin 300072China School of Foreign Languages Henan UniversityKaifeng 475000China

Herein,we discovered that the surface-confined condensation of boronic acid can happen spontaneously at room temperature,by comparing the kinetics of condensation of boronic acids with and without the negative sample bias,we found that the negative sample bias indeed accelerates the self-condensation reaction of boronic *** with in-situ STM images and ultraviolet photoemission spectrum(UPS)analysis,a reversible adsorption mechanism model was proposed and reasonably explains the reversible electric-field-induced phase transformation.

关键词： Boronic acids Electric-field-induced condensation Spontaneous condensation Surface-confined synthesis Scanning tunneling microscopy

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认识腐植酸对作物生长和土壤健康的作用

腐植酸 2024年第1期 18-30页

作者： Kwame Ampong Malinda S.Thilakaranthna Linda Yuya Gorim 孙梦宇肖凡缪春语宋亚茹孙志梅(译) 加拿大阿尔伯塔大学农业、食品与营养科学系埃德蒙顿T6G 2R3 河北农业大学资源与环境科学学院保定071000

腐植酸(HA)是有机分子,在改善土壤性质、植物农艺性状和生长方面发挥着重要作用。HA的来源包括煤、褐煤、土壤和有机材料。近年来,为了保证农业生产的可持续性,以HA为原料的产品已广泛应用于农作物生产中。相关研究表明,HA对土壤的物理... 详细信息

腐植酸(HA)是有机分子,在改善土壤性质、植物农艺性状和生长方面发挥着重要作用。HA的来源包括煤、褐煤、土壤和有机材料。近年来,为了保证农业生产的可持续性,以HA为原料的产品已广泛应用于农作物生产中。相关研究表明,HA对土壤的物理、化学和生物学性质都有积极的影响,包括土壤质地、结构、持水量、阳离子交换容量(CEC)、pH、土壤碳氮循环、酶活性和养分有效性等等。本文着重介绍了HA对作物生长、激素分泌、养分吸收和同化、产量和蛋白质合成的影响。HA对土壤性质和作物的影响受HA类型、HA施用量、HA施用方式、土壤类型、溶解度、分子大小和官能团的影响。本文还指出了HA领域亟待研究的一些知识空白。在不同轮作体系、氮肥形态、地点和气候条件下,HA及其施用量的相关田间试验研究还比较有限。此外,HA的化学和分子结构、水溶和碱溶组分也缺少田间试验验证以评估其对作物产量、品质和土壤健康的影响。施用HA后土壤-植物养分有效性与植物养分吸收之间的关系也有待进一步研究。

关键词：腐植酸腐殖质植物生长农艺参数土壤性质养分有效性

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密度泛函理论下的电负性均衡及应用

化学通报 2000年第6期63卷 14-20页

作者：赵东霞宋雅茹辽宁师范大学化学系大连116029 北京师范大学化学系 100875

以密度泛函理论为框架 ,综述电负性和电负性均衡理论的发展及其在探讨各种分子性质时的应用。

关键词：密度泛函理论电负性均衡应用量子化学计算

Hydrochemistry predominantly shapes the unique nitrogen-fixing bacterial communities in Tibetan hot springs

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Journal of Earth Science 2024年

作者： Zhao-Qi song Li Wang yaru Ma Dandan Deng Yang song Feng Liang Xiangyu Guan Wen-Jun Li Hongchen Jiang School of Ocean Sciences， China University of Geosciences Beijing State Key Laboratory of Biocontrol， Guangdong Key Laboratory of Plant Resources， School of Life Sciences， Sun Yat-sen University Engineering Technology Research Center of Biomass Degradation and Gasification， College of Biology and Food， Shangqiu Normal University State Key Laboratory of Biogeology and Environmental Geology， China University of Geosciences

The Tibetan Plateau has a large number of hot springs with varying temperatures and hydrochemistry， high elevation， and limited nitrogenous nutrition. Nitrogen-fixing bacteria (NFB) can fix N2to form ammonia and thus provide bioavailable nitrogen. However， there is limited knowledge about the distribution of NFB and its influencing factors in Tibetan hot springs. Here， we measured hydrochemical variables of the hot springs with a wide temperature range (32–77 ℃) in the Qucai and Daggyai geothermal zones on the Tibetan Plateau and investigated the composition of NFB using high-throughput sequencing of 16S rRNA and nifH genes. The Cl-/SO42-ratio in Qucai hot springs was higher than that in Daggyai， indicating that Qucai and Daggyai hot springs were more affected by the supply of liquid and gaseous phases， respectively. The NFB communities consisted predominantly of Nirtospirae， Chloroflexi， Deltaproteobacteria and an unidentified clade， with the last three acting as the main NFB with over 42% of the communities (the proportions are significantly larger than those found in hot springs of other geothermal regions). This demonstrates the uniqueness of NFB communities in Tibetan hot springs. NFB richness was limited by temperature in the studied Tibetan hot springs and was significantly lower than in low-elevation geothermal regions. The NFB community was predominantly affected by hydrochemistry， in contrast to the entire prokaryotic community， which was primarily influenced by temperature. This study expands our current understanding of NFB distribution and diversity as well as biogeochemical process in geothermal spring environments.

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固相分光激发光谱法测定合成色素

光谱学与光谱分析 2000年第5期20卷 741-743页

作者：宋雅茹吴红王德发徐建平北京师范大学化学系 100875 北京清华大学化学系北京100081

固相分光光度法是一种简单、快速、灵敏的新型痕量分析方法。本文首次提出用聚酰胺做固体吸附剂 ,采用激发光谱进行测定 ,克服了固相分光光度法背景大的缺点 ,同时能大幅度提高灵敏度 ,这种方法有良好的加标回收率、精密度及较高的准确... 详细信息

固相分光光度法是一种简单、快速、灵敏的新型痕量分析方法。本文首次提出用聚酰胺做固体吸附剂 ,采用激发光谱进行测定 ,克服了固相分光光度法背景大的缺点 ,同时能大幅度提高灵敏度 ,这种方法有良好的加标回收率、精密度及较高的准确度。并可将固相分光光度法的应用由仅能分析痕量的无机离子 ,推广到测定合成色素。

关键词：激发光谱合成色素分析固相分光光度法