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Synthetic Studies toward Pseudolaric Acids:Radical Cyclization to Form Bridged Scaffold

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Chinese Journal of Chemistry 2024年第15期42卷 1699-1705页

作者： Yujie niu Minggui Lin Hao Cui Yanji Huang yang Shen Yandong Zhang State Key Laboratoryof Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian ProvinceicHEMCollege of Chemistryand Chemical EngineeringXiamen UniversityXiamenFujian 361005China

Pseudolaric acids are a family of diterpenoid natural products that exhibit a broad spectrum of biological *** main structural feature of their framework is a trans-fused perhydroazulene bearing a bridged lactone positioned at the junction of the ***,we have developed a radical cyclization strategy that allows flexible tuning of the cyclization process through diverse silicon substitutions on the *** strategy can assist in constructing a series of skeletons with structural resemblance to pseudolaric acids and expedites the construction of the bridged ***,it facilitates the synthesis of the entire skeletal structure of the pseudolaric acidfamily of natural products,excludingthe B-ringfunctionalization.

关键词： Terpenoids Total synthesis Radical cyclization Bridged cycles Regioselectivity

Circumscription of the East Asia clade (Apiaceae subfamily Apioideae) and the taxonomic placements of several problematic genera

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Plant Diversity 2024年第2期46卷 206-218页

作者： jing Zhou Xinyue Wang Shilin Zhou Junmei niu Jiarui Yue Zhenwen Liu Stephen R.Downie School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical University1168 Western Chunrong RoadYuhua StreetChenggong New CityKunming 650500China Yunnan Academy of Forestry and Grassland Kunming 650201China Gaoligong Mountain Forest EcosystemObservation and Research Station of Yunnan ProvinceKunming 650201China Yunnan Key Laboratory of Biodiversity of Gaoligong Mountain Kunming 650201China Department of Plant Biology University of Illinois at Urbana-ChampaignUrbanaIL 61801USA College of Modern Biomedical Industry Kunming Medical UniversityKunming 650500China

The East Asia(or Physospermopsis) clade was recognized in previous molecular phylogenetic investigations into the higher-level relationships of Apiaceae subfamily Apioideae. The composition of this clade, the phylogenetic relationships among its constituent taxa, and the placement of species previously determined to be problematic have yet to be resolved. Herein, nr DNA ITS sequences were obtained for150 accessions of Apioideae, representing species whose distributions are in East Asia or genera having one or more species included within the East Asia clade. These data, along with published ITS sequences from other Apioideae(for 3678 accessions altogether), were subjected to maximum likelihood and Bayesian inference analyses. The results show that the East Asia clade contains representatives of 11currently recognized genera: Hansenia, Hymenolaena, Keraymonia, Sinolimprichtia, Acronema, Hymenidium, Physospermopsis, Pimpinella, Sinocarum, Tongoloa, and Trachydium. However, the latter seven genera have members falling outside of the East Asia clade, including the generic types of all except Tongoloa. Within the clade, the species comprising these seven genera are widely intermingled, greatly increasing confusion among relationships than previously realized. The problematic species Physospermopsis cuneata is confirmed as falling within the East Asia clade, whereas P. rubrinervis allies with the generic type in tribe Pleurospermeae. Physospermopsis kingdon-wardii is confirmed as a member of the genus Physospermopsis, whereas the generic attributions of P. cuneata and Tongoloa stewardii remain unclear. Two species of Sinocarum(S. filicinum and S. wolffianum) are transferred into the genus Meeboldia. This is the most comprehensive molecular phylogenetic investigation of the East Asia clade to date, and while the results increase systematic understanding of the clade, they also highlight the need for further studies of one of the most taxonomically intractable groups in Api

关键词： Physospermopsis Pimpinella Sinocarum Tongoloa Trachydium

Synergistic CO_(2) mineralization using coal fly ash and red mud as a composite system

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International Journal of Coal Science & Technology 2024年第3期11卷 149-158页

作者： Zhenchao Yao Yugao Wang Jun Shen Yanxia niu Jiang Feng yang Xianyong Wei School of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuanShanxi030024China Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationUniversity of Mining&Technology221116XuzhouJiangsuChina

CO_(2) mineralization plays a critical role in the storage and utilization of CO_(2).Coal fly ash(CFA)and red mud(RM)are widely utilized as CO_(2) ***,the inert calcium species in CFA limit its carbonation capacity,meanwhile the substantial Ca^(2+)releasing of RM is hindered by a covering layer of calcium *** this study,CO_(2) mineralization in a composite system of CFA and RM was investigated to enhance the carbonation *** analyzers were employed to characterize the raw materials and resulting mineralization *** results demonstrated that a synergistic effect existed in the composite system of CFA and RM,resulting in improving CO_(2) mineralization rate and *** produced calcium carbonate was ectopically attached the surface of CFA in the composite system,thus slowing down its coverage on the surface of *** phenomenon facilitated further releasing Ca^(2+)from the internal RM,thereby enhancing CO_(2) mineralization ***,the inclusion of RM significantly improved the alkalinity of the composite system,which not only promoted the dissolution of Ca^(2+)of the inert CaSO_(4)(H_(2)O)_(2) in CFA,but also accelerated CO_(2) mineralization *** investigation would be beneficial to CO_(2) mineralization using industrial solid wastes.

关键词： CO_(2)mineralization Coal fly ash Red mud Synergistic effect

Solid-state NMR study of the stability of MOR framework aluminum

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Chinese Journal of Structural Chemistry 2024年第4期43卷 7-14页

作者： Xinzhi Ding Chong Liu jing niu Nan Chen Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry Dalian University of TechnologyDalian116024China

MOR zeolite has been effectively utilized for dimethyl ether(DME)carbonylation reaction due to its unique pore structure and *** industrial production,the transformation of ammonium type MOR zeolite(NH_(4)-MOR)into proton type MOR zeolite(H-MOR)causes inevitable ***,understanding the influencing factors and dynamic evolution mechanism of zeolite dealumination is *** this work,the stability of framework aluminum was studied by X-ray diffraction(XRD),Fourier transform infrared(FT-IR)spectroscopy,^(29)Si,^(27)Al,^(1)H magic angle spinning nuclear magnetic resonance(MAS NMR),and DME carbonylation performance *** results indicate that extra-framework cation Na^(+)and NH_(4)^(+)could better preserve the aluminum structure of the MOR zeolite framework compared to H^(+),primarily due to the different'attraction'of the framework to ***,the impact of water on the zeolite framework aluminum at high temperature was studied by manipulating the humidity of the calcination atmosphere,revealing the formation of extra-framework six-coordinated aluminum(Al(Ⅵ)-EF)and the mechanism of water influence on the zeolite framework aluminum.

关键词： H-MOR Solid-state NMR H2O Framework aluminum stability Dealumination

Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

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Eye and Vision 2024年第3期10卷 31-40页

作者： Lingling niu Zhe Zhang Huamao Miao jing Zhao Xiaoying Wang Ji C.He Xingtao Zhou Department of Ophthalmology and Optometry Eye&ENT HospitalFudan UniversityShanghaiChina NHC Key Laboratory of Myopia(Fudan University) ShanghaiChina Key Laboratory of Myopia Chinese Academy of Medical SciencesShanghaiChina Shanghai Research Center of Ophthalmology and Optometry ShanghaiChina New England College of Optometry MABostonUSA

Background To investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens(ICL V4c).Methods This observational study recruited 62 eyes of 31 myopia patients underwent ICL V4c *** segment optical coherence tomography(AS-OCT)assessed the anterior chamber depth(ACD),ACD-ICL(distance from the corneal endothelium to anterior surface of the ICL V4c),vault(distance between the posterior ICL V4c surface and anterior crystalline lens surface),and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after ICL V4c *** was defined as the scotopic condition,which was also the non-accommodative stimulus *** ICL V4c tilt was analyzed using *** significance level was set at P<*** The ACD-ICL values were similar under various lighting conditions(P=0.978)but decreased during accommodation(P<0.001).The vault was significantly smaller under mesopic and photopic conditions than the baseline(P=0.044 and P<0.001,respectively)but remained unchanged during accommodation(P=0.058).The inferotemporal proportion of ICL V4c(88.7%,55 eyes)and crystalline lens(74.2%,46 eyes)tilts were not significantly different(P=0.063).Crystalline lens under various lighting conditions and accommodation exhibited similar *** vertical tilt of ICL V4c was significantly larger under photopic conditions than the baseline(P=0.038).The horizontal and total tilts were significantly decreased during accommodation(P=0.043 and 0.013,respectively).Conclusions The axial position of ICL V4c in the anterior chamber was stable under various lighting *** conditions and accommodation may influence vertical,horizontal and total tilts of ICL V4c.

关键词： Implantable collamer lens Anterior segment optical coherence tomography Myopia Tilt

新型一维锯齿链状聚金属氧酸盐配位聚合物[{La(DMSO)_(6)(H_(2)O)}(PMo_(12)O_(40))·H_(2)O]_(n)的合成、结构及表征

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化学学报 2003年第8期61卷 1276-1280页

作者：王敬平魏梅林牛景杨河南大学化学化工学院开封475001

以α-H_(3)PMo_(12)O_(40)·nH_(2)O,La_(2)O_(3)和二甲基亚砜(DMSO)为原料,在乙腈和水的混合溶剂中制得了一维锯齿链状配位聚合物[{La(DMSO)_(6)(H_(2)O)}(PMo_(12)O_(40))·H_(2)O]_(n).X射线单晶衍射结果表明,聚合物中金属配阳离子与杂多阴离子骨架通过Mo Od La Od Mo相连并形成一维无限链,每一个不对称结构单元中含一个结晶水,La^(3+)的配位数为九,三帽三棱柱构型,配位氧原子分别来自6个DMSO分子,1个H_(2)O分子和2个相邻杂多阴离子的端氧.晶体属于单斜晶系,P2_(1)/c空间群,a=13916(3)nm,b=17058(3)nm,c=24750(5)nm,β=9916(3)°,Z=4,V=5800(2)nm^(3),Dc=2825g/cm^(3),R_(1)=00446,wR_(2)=***光谱和X射线单晶衍射结果一致表明,在固态条件下配阳离子和杂多阴离子之间存在相互作用.UV光谱表明,在稀的水溶液中,由于溶剂化作用,杂多阴离子与配阳离子处于解离状态.热性质研究表明,形成标题化合物后。

关键词：合成聚金属氧酸盐聚合物晶体结构 Keggin结构

Covalently bonded ternary photocatalyst comprising MoSe_(2)/black phosphorus nanosheet/graphitic carbon nitride for efficient moxifloxacin degradation

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Chinese Chemical Letters 2024年第9期35卷 356-359页

作者： Yuhao Ma Yufei Zhou Mingchuan Yu Cheng Fang Shaoxia yang Junfeng niu College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China College of Water Conservancy and Hydropower Engineering North China Electric Power UniversityBeijing 102206China Global Centre for Environmental Remediation(GCER) University of NewcastleCallaghanNSW 2308Australia

Covalently bonded bridging between different semiconductors is a remarkable approach to improve the transfer of charge carriers at *** this study,we designed a ternary heterojunction(MBG)combining of molybdenum diselenide(Mo Se_(2)),black phosphorus nanosheets(Bpn)and graphitic carbon nitride(GCN).Among this MBG of Mo Se_(2)/Bpn/GCN,(i)the covalently bonded bridging effect between Bpn/GCN facilitates directional charge carrier transfer,meanwhile(ii)a Z-scheme heterojunction is formed between Mo Se_(2)/GCN to enhance the separation of photogenerated ***,(iii)this composite exhibits an increased absorption for visible *** this MBG,photocatalytic degradation of over 98%of moxifloxacin is achieved within 20 min,with O_(2)·-confirmed as the primary photocatalytic active *** findings provide novel insights into the construction of efficient heterojunction by covalently bonded bridging.

关键词： Ternary heterojunction Black phosphorus nanosheets Covalent bond Photocatalytic degradation Graphitic carbon nitride

The swirl and pyrolysis reaction synergistically enhance solid-solid heat transfer and product separation in cyclone pyrolyzer Author links open overlay panel

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Particuology 2024年第8期91卷 118-127页

作者： Haorui niu jingxuan yang Wenhao Lian Nan Zhang Yongguo Li Hongzheng Ren Xiaogang Hao Guoqing Guan College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan030024 China School of Chemical Engineering and Technology North University of ChinaTaiyuan030051 China CNNC Key Laboratory on Radioactive Gas Purification Technology China Institute for Radiation ProtectionTaiyuan030006 China Energy Conversion Engineering Laboratory Institute of Regional InnovationHirosaki University3-BunkyochoHirosaki036-8561Japan

Cyclone pyrolyzer is a novel type of downer that combines centrifugal force field and double-layer cyclone *** on transfer behavior is helpful to optimize the pyrolyzer to meet the needs of *** this study,the Computational Particle Fluid Dynamics(CPFD)model is used to analyze the transfer behavior of binary particles,and finds that the swirl and reaction have a synergistic *** effect can increase the heating rate of the particles to the range of flash pyrolysis,and its mechanism lies in the flow field structure of the *** to the centrifugal force field,the particles gather to the near *** rapid swirl,which facilitates intense gas-solid heat transfer,leads to the rapid heating and pyrolysis of biomass *** the pyrolysis proceeds,the mass of the biomass particles becomes smaller and they are more easily affected by the gas flow in *** the action of gas flow,char particles serve as new heat carrier to form the inner cycle of particles,which strengthens the heating *** pyrolysis products are discharged from the exhaust port in time with the flow field of the pyrolyzer to achieve separation from the heat carrier and inhibit the occurrence of secondary reactions.

关键词： Biomass pyrolysis Cyclone pyrolyzer Intra-particle circulation Synergistic effect

Biochar-based materials as remediation strategy in petroleum hydrocarbon-contaminated soil and water:Performances,mechanisms,and environmental impact

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Journal of Environmental Sciences 2024年第4期138卷 350-372页

作者： Zhuo Wei YiWei yang Liu Shuai niu Yaxi Xu Jong-Hwan Park Jim J.Wang Faculty of Environmental Science&Engineering Kunming University of Science&TechnologyKunming 650500China School of Plant Environment&Soil SciencesLouisiana State University AgCenter.Baton RougeLA 70803USA Department of Life Resources Industry Dong-A University37Nakdong-daero 550 beon-gilSaha-guBusan 49315South Korea

Petroleum contamination is considered as a major risk to the health of humans and *** as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the *** purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and ***,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically *** addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and ***,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were ***,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar ***,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.

关键词： Petroleum contamination Adsorbent Bioremediation Biochar modification Ecotoxicity