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Asymmetric Hydrogenation of Phenanthridines with Chiral Boranes

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Chinese Journal of Chemistry 2024年第6期42卷 631-635页

作者： Guangyu Cui xiangqing feng Haifeng Du Beijing national Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

The asymmetric hydrogenation of n-heteroarenes provides an efficient method for the synthesis of optically active cyclic secondary *** this paper,we described an asymmetric hydrogenation of phenanthridines using a chiral mono-alkene-derived borane.A variety of dihydrophenanthridines were furnished in high yields with up to 93%*** current catalytic system was very sensitive for the steric hindrance of *** substituents at one phenyl group of phenanthridines were required to obtain the high *** large substituents on the carbon of the C=n bonds would diminish the reactivity sharply.

关键词： Asymmetric catalysis Hydrogenation nitrogen heterocycles Phenanthridines Frustrated Lewis pairs Chiral boranes

Stability Analysis of a Class of nonlinear Fractional Differential Systems With Riemann-Liouville Derivative

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1883-1885页

作者： Ruoxun Zhang Shiping Yang Shiwen feng College of Teacher Education Xingtai UniversityXingtai 054001China College of Physics and Information Engineering Hebei Normal UniversityShijiazhuang 050016China

Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville *** using the Mittag-Leffler function,Laplace transform and the Gronwall-Bellman lemma,one sufficient condition is attained for the asymptotical stability of a class of nonlinear fractional differential systems whose order lies in(0,2).According to this theory,if the nonlinear term satisfies some conditions,then the stability condition for nonlinear fractional differential systems is the same as the ones for corresponding linear *** examples are provided to illustrate the applications of our result.

关键词： Liouville Riemann nonlinear

Primitive functional groups directed distinct photocatalytic performance of imine-linked donor-acceptor covalent organic frameworks

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nano Research 2024年第6期17卷 4994-5001页

作者： xitong Ren Jiajie Sun Yusen Li feng Bai Key Laboratory for Special Functional Materials of Ministry of Education National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting TechnologySchool of Materials Science and Engineeringand Collaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityKaifeng 475004China School of Physics and Electronics Henan UniversityKaifeng 475004China

The combination of donor-acceptor(D-A)structures presents a viable strategy for fabricating covalent organic frameworks(COFs)with exceptional photocatalytic ***,the selection of functional groups on donor or acceptor building blocks and their effect on the macroscopic properties of COFs are *** this study,we tactfully synthesized a pair of Py-DBT-COFs from the same pyrene(Py)donor and 4,7-diphenylbenzo[c][1,2,5]thiadiazole(DBT)acceptor cores with distinct primitive functional *** primitive functional groups of building units determine the photocatalytic properties of corresponding ***,Py-C-DBT-COF synthesized from Py-4CHO and DBT-2nH_(2)showcases a splendid H_(2)evolution rate as high as 21,377.7μmol/(g·h)(with 5 wt.%Pt)originating from better charge transfer capacity,which is significantly superior to that of Py-n-DBT-COF constructed from Py-4nH_(2)and *** distinct photocatalytic performances of the two COFs are demonstrated to originate from the different charge separation and transfer *** work supplies a new avenue for optimizing the photocatalytic performance of D-A COFs from the perspective of primitive functional group selections.

关键词： covalent organic frameworks functional group donor-acceptor photocatalysis

Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-n,3-dimethylbenzamide: A case series

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 186-194页

作者： Meng-xiao feng Hua Zou Yuan-Qiang Lu Department of Emergency Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Key Laboratory for Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province Hangzhou 310003China Occupational Health and Radiation Protection Institute Zhejiang Provincial Center for Disease Control and PreventionHangzhou 310051China

Background:The 2-amino-5-chloro-n,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and ***,no literature currently exists on 2-amino-5-chloro-n,3-dimethylbenzamide poisoning in *** study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-n,3-dimethylbenzamide ***:This observational study included four patients with 2-amino-5-chloro-n,3-dimethylbenzamide poisoning from June 2022 to July *** entire course of the incidents was described in *** 2-amino-5-chloro-n,3-dimethylbenzamide concentrations were detected by a mass ***-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic ***:The 2-amino-5-chloro-n,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective *** typical course of 2-amino-5-chloro-n,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical *** and fever may be the important premonitory symptoms for further organ *** chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and *** patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive *** patient survived by liver *** postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual ***:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-n,

关键词： 2-amino-5-chloro-n,3-dimethylbenzamide Poisoning Clinical characteristics Liver injury

nHC-derived carbon-centered luminescent radicals with shortwavelength emission via suppression of Kasha's rule

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Science China Chemistry 2024年第8期67卷 2679-2685页

作者： Can Chen xin Li xinhua Ouyang Ying-feng Han Key Laboratory of Synthetic and natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou 350108China

Luminescent organic radicals have garnered increasing attention owing to their versatile applications in sensing, imaging, and organic light-emitting diodes(OLEDs), attributed to their unique emission properties originating from the doublet spin ***, the natural narrow bandgap of organic free radicals typically limits their emission to the long-wavelength *** luminescent organic radicals with short-wavelength emission remains a significant challenge. Herein, a series of carbon-centered radicals with short-wavelength emission(383–476 nm) by combining n-heterocyclic carbenes with various polycyclic aromatic hydrocarbons(PAHs)(2-naphthyl, 2a~Ⅰ and 2b~Ⅰ;2-phenanthryl, 2a~Ⅱand 2b~Ⅱ;2-anthryl, 2a~Ⅲand 2b~Ⅲ;3-phenanthryl, 2a~Ⅳand 2b~Ⅳ). Theoretical calculations reveal that the introduction of PAHs significantly increases the ΔE_(D2-D1) in 2a^(Ⅰ–Ⅲ)and 2b^(Ⅰ–Ⅲ)compared to that in phenyl-derived radical congeners. Consequently, the internal transition from D2 to D1 is impeded, leading to a high yield of D2 emission and a suppressed Kasha's rule, thereby overcoming the limitations imposed by their narrow bandgap. For 2a~Ⅳ and 2b~Ⅳ, despite a moderately large ΔED2-D1value, the ΔED3-D1value exceeds 1 e V, indicating that their emission likely originates from the D3 state. Furthermore, we utilized 2a~Ⅲand 2b~Ⅲ as emissive materials in OLEDs,resulting in blue emissions with external quantum efficiencies of 7.5% and 6.5%, respectively.

关键词： n-heterocyclic carbenes luminescent organic molecules carbon-centered radicals short-wavelength emission

Synergistic integration of self-supported 1T/2H-WS_(2) and nitrogendoped rGO on carbon cloth for pH-universal electrocatalytic hydrogen evolution

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nano Research 2024年第3期17卷 1267-1280页

作者： feng Ming Yap Jian Yiing Loh Wee-Jun Ong School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Center of Excellence for nano Energy&Catalysis Technology(COnnECT) Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Gulei Innovation Institute Xiamen UniversityZhangzhou 363200China Shenzhen Research Institute of xiamen University Shenzhen 518057China

Hydrogen economy based on electrochemical water splitting exemplified one of the most promising means for overcoming the rapid consumption of fossil fuels and the serious deterioration of global *** development of earth-abundant,efficient,and durable electrocatalysts for hydrogen evolution reaction(HER)plays a vital role in the commercialization of water ***,the self-supported electrode with unique nitrogen-doped reduced graphene oxide(n-rGO)nanoflakes and WS_(2) hierarchical nanoflower that were grown directly on carbon cloth(CC)substrate(WS_(2)/n-rGO/CC)was successfully synthesized using a facile dual-step hydrothermal *** as-synthesized 50%1T/2H-WS_(2)/n-rGO/CC(WGC),which possessed high metallic 1T phase of 57%not only efficiently exposed more active sites and accelerated mass/charge diffusion,but also endowed excellent structural lustiness,robust stability,and durability at a high current *** a result,the 50%WGC exhibited lower overpotentials and Tafel slopes of 21.13 mV(29.55 mV∙dec^(-1))and 80.35 mV(137.02 mV∙dec^(-1))as compared to 20%Pt-C/CC,respectively for catalyzing acidic and alkaline hydrogen evolution ***,the as-synthesized 50%WGC also depicted long-term stability for more than 8 h in the high-current-density regions(100 and 220 mA∙cm^(-2)).In brief,this work reveals a self-supported electrode as an extraordinary alternative to Pt-based catalysts for HER in a wide pH range,while paving a facile strategy to develop advanced electrocatalysts with abundant heterointerfaces for practical applications in energy-saving hydrogen production.

关键词： self-supported electrocatalyst carbon-based substrate phase engineering pH-universal water splitting

Variability of the Pacific subtropical cells under global warming in CMIP6 models

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Journal of Oceanology and Limnology 2024年第1期42卷 24-40页

作者： xue HAn Junqiao feng Yunlong LU Dunxin HU Key Laboratory of Ocean Circulation and Waves Chinese Academy of SciencesQingdao 266071China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for Ocean Dynamics and Climate Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

The Pacific subtropical cells(STCs)are shallow meridional overturning circulations connecting the tropics and subtropics,and are assumed to be an important driver of the tropical Pacific decadal *** variability of STCs under global warming is investigated using multimodal outputs from the latest phase of the Coupled Model Inter-comparison Project(CMIP6)and ocean reanalysis ***,the volume transport diagnostic analysis is employed to evaluate how coupled models and ocean reanalysis products reproduce interior STC *** variation of heat transport by the interior STC under the high-emissions warming scenarios is also *** results show that the multimodal-mean linear trends of the interior STC transport along 9°S and 9°n are-0.02 Sv/a and 0.04 Sv/a under global warming,respectively,which is mainly due to the combined effect of the strengthened upper oceanic stratification and the weakening of wind *** is a compensation relationship between the interior STC and the western boundary transport in the future climate,and the compensation relationship of 9°S is more significant than that of 9°*** addition,compared with ocean reanalysis products,the coupled models tend to underestimate the variability of the interior STC transport convergence,and thus may lose some sea surface temperature(SST)driving force,which may be the reason for the low STC-SST correlation simulated by the *** future scenario simulation shows that the heat transport of interior STC is weakened under global warming,with a general agreement across models.

关键词： interior subtropical cell(STC) global warming Coupled Model Inter-comparison Project(CMIP6) western boundary transport

Cu,n codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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Journal of Energy Chemistry 2024年第4期91卷 27-35页

作者： Yonghai feng Min Yu Minjia Meng Lei Liu Dewei Rao Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(nPs)due to their limited oxygen reduction rate and easy C-C *** the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-n-C)were developed to realize highly selective of PDO oxidation to *** carbon-encapsulated ultrasmall Cu^(0)nPs in Cu@Cu-n-C have high PDO dehydrogenation activity while n-coordinated Cu(Cu-n)sites are responsible for the high oxygen reduction ***,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→***,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-n-C with strong leaching resistance for better recycling.

关键词： Selective oxidation Copper and nitrogen doped carbon 1,2-Propanediol Ultrasmall Cu nanoparticles Lactic acid

RnA m6A dynamic modification mediated by nucleuslocalized FTO is involved in follicular reserve

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Zoological Research 2024年第2期45卷 415-428页

作者： Jiao-na Zhang Rui-Ting Wang Francesca-Gioia Klinger Shun-feng Cheng Wei Shen xiao-feng Sun College of Life Sciences Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of ShandongQingdao Agricultural UniversityQingdaoShandong 266109China Department of Biomedicine and Prevention University of Rome Tor VergataRome 00133Italy

In eukaryotic organisms,the most common internal modification of messenger RnA(m RnA)is n6-methyladenosine(m6A).This modification can be dynamically and reversibly controlled by specific enzymes known as m6A writers and *** fat-mass and obesity-associated protein(FTO)catalyzes RnA demethylation and plays a critical role in various physiological and pathological *** research identified dynamic alterations in both m6A and FTO during the assembly of primordial follicles,with an inverse relationship observed for m6A levels and nuclear-localized FTO *** of Fto small interfering RnA(si RnA)altered the expression of genes related to cell proliferation,hormone regulation,and cell chemotaxis,and affected RnA alternative *** of the full-length Fto gene led to changes in m6A levels,alternative splicing of Cdk5,cell proliferation,cell cycle progression,and proportion of primordial ***,overexpression of Fto lacking a nuclear localization signal(nLS)did not significantly alter m6A levels or primordial follicle *** findings suggest that FTO,localized in the nucleus but not in the cytoplasm,regulates RnA m6A demethylation and plays a role in cell proliferation,cell cycle progression,and primordial follicle *** results highlight the potential of m6A and its eraser FTO as possible biomarkers and therapeutic targets.

关键词： m6A FTO Ovary Primordial follicle assembly Alternative splicing