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Petroleum Science 2023年第2期20卷 1231-1237页

作者： Ji-xing Liu Xiang-Qi Liu Ri-Xin Yan Ling-Feng Ji Hui-Fang Cheng Hui Liu yan Huang Ming-Qing Hua Hua-Ming Li Wen-Shuai Zhu School of Chemistry and Chemical Engineering and Institute for Energy Research Jiangsu UniversityZhenjiangJiangsu 212013China State Key Laboratory of Heavy Oil Processing and Beijing Key Lab of Oil&Gas Pollution Control China University of PetroleumBeijing 102249China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalianLiaoning 116024China

Herein,we designed and constructed a mesoporous LaAlOx via a solvent evaporation induced self-assembly protocol.The structure and physicochemical property of the corresponding NiMo supported catalyst was analyzed by a set of characterizations,and its catalytic activity was investigated for hydrodesulfurization(HDS)of 4,6-dimethyldibenzothiophene.It has confirmed that the incorporation of La profoundly facilitate the generation of“Type II”NiMoS phase by weakening the interaction of Mo–O–Al leakage and promoting the sulfidation of both Ni and Mo oxides as well as changing the morphology of Ni promoted MoS2 slabs,thereafter boosting the HDS performance substantially.The finding here may contribute to the fundamental understanding of structure-activity in ultra-deep desulfurization and inspire the advancement of highly-efficient HDS catalyst in future.

关键词： NiMo supported Catalyst LaAlOx composites Hydrodesulfurization Morphology Reaction kinetics

Investigation into keyhole-weld pool dynamic behaviors based on HDR vision sensing of real-time K-TIG welding process through a steel/glass sandwich

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Advances in Manufacturing 2021年第1期9卷 136-144页

作者： yan-xin Cui Yong-Hua Shi Qiang Ning Yun-Ke Chen Bao-ri Zhang Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510640People's Republic of China

To obtain a deep insight into keyhole tungsten inert gas welding,it is necessary to observe the dynamic behavior of the weld pool and keyhole.In this study,based on the steel/glass sandwich and high dynamic range camera,a vision system is developed and the keyhole-weld pool profiles are captured during the real-time welding process.Then,to analyze the dynamic behavior of the weld pool and keyhole,an image processing algorithm is proposed to extract the compression depth of the weld pool and the geometric parameters of the keyhole from the captured images.After considering the variations of these parameters over time,it was found that the front and rear lengths of the keyhole were dynamically adjusted internally and had opposite trends according to the real-time welding status while the length of the keyhole was in a quasi-steady state.The proposed vision-based observation method lays a solid foundation for studying the weld forming process and improving keyhole tungsten inert gas welding.

关键词： Keyhole tungsten inert gas(K-TIG)welding Vision-based investigation Dynamic keyhole profile Dynamic weld pool profile

Effects of connecting sequences of building blocks on reticular synthesis of covalent organic frameworks

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Nano Research 2021年第2期14卷 381-386页

作者： De-Li Ma Cheng Qian Qiao-yan Qi Zhong-ri Zhong Guo-Fang Jiang xin Zhao State Key Lab of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan Universityf Changsha 410082China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China

The principle of reticular chemistry has been widely used to guide the design of crystalline porous materials such as metal organic frameworks(MOFs)and covalent organic frameworks(COFs).While in the early strategies only the symmetries of the building blocks were considered for reticular synthesis of COFs,recently a few researches on COFs with hierarchical porosities indicate that connecting sequence of building blocks also plays a crucial role in determining crystalline structures of COFs.However,this important phenomenon has not been systematically investigated yet.In this article,a model system has been established to demonstrate how different connecting sequences of two C_(2v)-symmetric building blocks lead to the formation of four two-dimensional(2D)COFs with distinct framework structures.To verify this concept,target synthesis was conducted to produce three COFs,whose structures were confirmed by powder X-ray diffraction and pore size distribution analysis.

关键词： reticular chemistry covalent organic framework connecting sequence building block

Neamine-heterocycle conjugates as potential anti-HIV agents

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Chinese Chemical Letters 2013年第4期24卷 273-278页

作者： ri-Bai yan yan-Fen Wu Jun Liu Xiao-Lian Zhang xin-Shan Ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University State Key Laboratory of Virology Department of ImmunologyHubei Province Key Laboratory of Allergy and ImmunologyWuhan University School of Medicine

A series of neamine-heterocycle conjugates were designed and synthesized. All new compounds displayed more potent inhibitory effect on HIV replication than neamine, among them two compounds displayed stronger anti-HIV activity than neomycin B. The results suggested that it might be a promising approach to modify neamine for the discovery of new anti-HIV agents.

关键词： Aminoglycoside Anti-HIV Neamine Synthesis

Meroterpenoids Possessing Diverse Rearranged Skeletons with Anti-inflammatory Activity from the Mangrove-Derived Fungus Penicillium sp. HLLG-122

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Chinese Journal of Chemistry 2023年第19期41卷 2507-2517页

作者： Yu-Yue Qin Wan-Shan Li Xuan Zhang Zhang-xin Yu Xiao-Bao Li Han-Yi Chen yan-Ru Lv Chang-ri Han Guang-Ying Chen Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education and Key Laboratory of Tropical Medicinal Plant Chemistry of Hainan Province College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikouHainan571158 China Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikouHainan571126 China

Fifteen new meroterpenoids, littoreanoids A—O (1—15), including three rearranged skeleton meroterpenoids (1—3), were isolated from the mangrove-derived fungus Penicillium sp. HLLG-122. Compound 1 was a novel berkeleyacetal-derived meroterpenoid featuring an unusual spirocyclic 2-oxaspiro[5.5]undeca-4,7-dien-3-one moiety. Compound 2 possessed an unusual 6/6/6/6/6 pentacyclic system with a novel 1-hydroxy-7,7-dimethyl-2-oxabicyclo[2.2.2]octan-5-yl acetate moiety. Compound 3 was an unusual 6/7/6/5/6/5/4 polycyclic systems containing a β-lactone ring. The structures and absolute configurations of new compounds were elucidated by HRESIMS, NMR spectroscopy, single crystal X-ray diffraction analysis, and electronic circular dichroism calculations. The plausible biosynthetic pathways of 1—3 were also proposed. Compounds 6 and 11 exhibited anti-inflammatory effects with IC_(50) values of 30.41 and 19.02 μmol/L, respectively. The bioactive compound 11 was selected for the investigation of preliminary mechanism using molecular docking and Western blotting experiments. Compound 11 could suppress the levels of TNF-α and IL-6, and down-regulate the protein expression of iNOS and COX-2 in RAW 264.7 cells.

关键词： Penicillium sp Terpenoids Structural elucidation Anti-inflammatory activities Conformation analysis Natural products

Crosstalk of cold and gibberellin effects on bolting and flowering in flowering Chinese cabbage

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Journal of Integrative Agriculture 2019年第5期18卷 992-1000页

作者： SONG Shi-wei LEI Yu-ling HUANG xin-min SU Wei CHEN ri-yuan HAO yan-wei College of Horticulture South China Agricultural University

The flower stalk is the product organ of flowering Chinese cabbage(Brassica campestris L.ssp.chinensis var.utilis Tsen et Lee),which is cultivated extensively in South China.Flower stalk formation and development,including bolting and flowering,determine the yield of flowering Chinese cabbage;however,the bolting and flowering mechanisms remain to be explored.To elucidate these processes,we studied the effects of low-temperature and gibberellin(GA)treatments,and their interaction,on stem elongation,bolting time,flowering time,hormone content,and cell morphology in stem of flowering Chinese cabbage.The results showed that both cold and GA treatments accelerated bolting time,stem elongation,and flowering time.Moreover,cold and GA cotreated plants displayed additive positive effects.In addition,cold treatments increased the GA,indole-3-acetic acid,and cytokinin contents and altered cell size in the shoot apices of flowering Chinese cabbage.Treatment with uniconazole,a GA synthesis inhibitor,strongly delayed bolting time,stem elongation,and flowering time,whereas GA,but not cold treatment,rescued this inhibition,indicating that low temperature accelerates bolting and flowering not only through inducing GA in the shoot apices,but also other ways.These results provide a theoretical basis for further dissecting the regulatory mechanism of bolting and flowering in flowering Chinese cabbage.

关键词： bolting flowering stem elongation cold gibberellin

Double Fano resonances in disk-nonconcentric ring plasmonic nanostructures

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Optoelectronics Letters 2024年第1期20卷 1-6页

作者： ZHANG xingfang LIU Fengshou LIANG Lanju yan xin School of Opt-Electronic Engineering Zaozhuang UniversityZaozhuang 277160China Laboratory of Optoelectronic Information Processing and Display of Shandong Zaozhuang 277160China

The plasmonic properties of gold nanostructures composed of a disk outside a nonconcentric ring are numerically studied by the finite difference time domain(FDTD)method.Simulated results show that two Fano resonances are formed as a result of the coupling of the octupolar and quadrupolar modes of the ring with the dipolar mode of the disk.The reduction in structural symmetry causes a red shift of the Fano resonances and distinct changes in spectral lineshape by offsetting the center of the inner surface of the ring to different directions.The effects of several geometric parameters on the characteristics of Fano resonances are also discussed.In addition,the refractive index(ri)sensitivities for the two Fano resonances can be up to 581 nm/riU and 780 nm/riU with the corresponding figure of merits(FOMs)as large as 12.7 and 10.2,respectively.Such properties render the structures useful for potential applications in multi-wavelength sensors.

关键词： method resonance render

Knowledge,attitude,and practice of patients living with inflammatory bowel disease:A cross-sectional study

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World Journal of Gastroenterology 2023年第43期29卷 5818-5833页

作者： Xiao-Xiao Shao Lu-yan Fang Xu-ri Guo Wei-Zhong Wang Rui-xin Shi Dao-Po Lin Department of Gastroenterology The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina The Second Clinical Medical College Wenzhou Medical UniversityWenzhou 325035Zhejiang ProvinceChina

BACKGROUND Patients with inflammatory bowel diseases(IBDs)generally have poor knowledge,attitude,and practice of their disease,while the data from China are lacking.AIM To address this knowledge disparity among Chinese patients with IBD.METHODS This web-based,cross-sectional study was conducted on a cohort of IBD patients who visited the Second Affiliated Hospital of Wenzhou Medical University between December 2022 and February 2023.Their socio-demographic information and the knowledge,attitude,and practice scores were collected and estimated using a self-designed questionnaire.Pearson’s correlation analysis was used to determine the pairwise correlations among knowledge,attitude,and practice scores.A multivariate logistic regression analysis was further performed to determine the independent factors associated with their knowledge,attitude,and practice scores.RESULTS A total of 353 patients(224 males)with IBD completed the questionnaires.The mean knowledge,attitude,and practice scores were 10.05±3.46(possible range:0-14),41.58±5.23(possible range:0-56),44.20±7.39(possible range:0-56),respectively,indicating good knowledge,positive attitude,and proactive practice toward IBD.Pearson’s correlation analysis showed that the knowledge score had significant positive correlations with the attitude score(r=0.371,Priate logistic regression analysis showed that aged 30-40 years[odds ratio(OR)=4.06,95%confidence interval(CI):1.04-15.82,P=0.043],middle school education(OR=3.98,95%CI:1.29-12.33,P=0.017),high school/technical secondary school education(OR=14.06,95%CI:3.92-50.38,P<0.001),and junior college/bachelor’s degree and above education(OR=15.20,95%CI:4.15-55.650,P<0.001)were independently associated with good knowledge.The higher knowledge score was independently associated with a positive attitude(OR=1.23,95%CI:1.11-1.36,P<0.001).The higher attitude score was inde

关键词： Attitude Cross-sectional study Inflammatory bowel disease Knowledge Practice Questionnaire

大数据税收征管能否抑制企业“脱实向虚”?——基于“金税三期”的准自然实验证据

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现代财经（天津财经大学学报） 2022年第7期42卷 37-56页

作者：李晓艳梁日新李英首都经济贸易大学会计学院北京100070 北京国家会计学院教研中心北京101318

实体企业金融化的加剧导致企业“脱实向虚”的现状越来越严重,进而阻碍了实体经济的发展。本文基于“金税三期”这一准自然实验,以2011-2018年A股上市公司为样本,采用多期双重差分法(DID)实证检验了大数据税收征管对企业金融化的影响及... 详细信息

实体企业金融化的加剧导致企业“脱实向虚”的现状越来越严重,进而阻碍了实体经济的发展。本文基于“金税三期”这一准自然实验,以2011-2018年A股上市公司为样本,采用多期双重差分法(DID)实证检验了大数据税收征管对企业金融化的影响及作用机制。研究发现,大数据税收征管显著降低了企业金融化程度。机制检验发现,大数据税收征管通过加剧企业融资约束、缓解代理问题进而抑制企业金融化,有效发挥了“征税效应”和“治理效应”。进一步分析表明,大数据税收征管对企业金融化的抑制作用在避税动机较强的企业以及公司治理水平较差的企业中更为显著,而在产权性质不同的企业中没有显著差异。本文丰富了企业金融化和税收征管的相关研究,也为数字经济背景下大数据技术在管理实践中的应用提供了参考。

关键词：大数据税收征管金融化征税效应治理效应

陈日新教授“无虚不作敏”学术思想与临床应用

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中国针灸 2020年第2期40卷 199-202页

作者：熊俊陈彦奇陈日新(指导) 江西中医药大学附属医院针灸科南昌330006 江西中医药大学针灸推拿学院

探讨陈日新教授"无虚不作敏"的学术思想,阐述热敏灸治疗过敏性疾病的理论与临床应用。认为过敏性疾病的关键病机是"敏多因虚",多因肺、脾、肾三脏虚损,外邪侵袭或伏邪引动而作敏。治法是"虚不远温""以敏治敏",根据二步定位法探寻敏化穴... 详细信息

探讨陈日新教授"无虚不作敏"的学术思想,阐述热敏灸治疗过敏性疾病的理论与临床应用。认为过敏性疾病的关键病机是"敏多因虚",多因肺、脾、肾三脏虚损,外邪侵袭或伏邪引动而作敏。治法是"虚不远温""以敏治敏",根据二步定位法探寻敏化穴位,施以艾条悬灸。热敏灸感是人体内源性调节功能被激活的标志。热敏灸疗法以外治内、切中病机、扶正息敏,是内源性抗过敏的新途径。

关键词：过敏性疾病无虚不作敏热敏灸名医经验陈日新