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Nuclear Science and Techniques 2016年第3期27卷 68-73页

作者： Yu Cui Xiao-Feng Yang Cheng Yang ye-xin li Guo-Zhu Chen Guo-xin Sun School of Chemistry and Chemical Engineering University of Jinan

The extraction of uranyl nitrate by novel extractants of N,N-dimethyl-N',N'-dioctylsuccinylamide(DMDOSA)and N,N-dimethyl-N',N'-didecylsuccinylamide(DMDDSA) from aqueous nitric/nitrate solutions was *** was found both the concentration of HNO_3 and extractants had an effect on the U(Ⅵ) extraction *** extraction mechanism was established,and stoichiometry of the main extracted species was confirmed to be UO_2(NO_3)_2·2DMDOSA and UO_2(NO_3)_2·2DMDDSA,*** of the extraction reactions are *** spectral study of the U(Ⅵ) extracted species was also made.

关键词：溶剂萃取二甲基环己烷 ftir光谱硝酸铀酰化学计量比 O3浓度萃取反应

Ultralight and compressive SiC nanowires aerogel for high-temperature thermal insulation

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Rare Metals 2023年第10期42卷 3354-3363页

作者： Jun-Xiong Zhang Jing Zhang xin-li ye Xiao-Ming Ma Rong liu Qi-Long Sun Yun-Lei Zhou School of Textile and Clothing Nantong UniversityNantong226019China School of Civil Aviation Northwestern Polytechnical UniversityXi’an710072China National Equipment New Materials&Technology(Jiangsu)Co. LtdSuzhou215101China Hangzhou Institute of Technology Xidian UniversityHangzhou311231China

Aerogels with excellent properties combination of ultralow density and great thermal insulation are drawing attention to applications in harsh *** aerogels,however,are usually constructed with nanoparticles with a weakness in physical *** silicon carbide nano wire(SiC_(NW)) is a kind of one-dimensional(1D) nano wire possessing the promising properties of flexibility,great thermal insulation,and stability at high *** aerogel constructed by the SiC_(NW) will produce a great material with a promising material,the amazing SiC_(NW) ***,a novel SiC_(NW) aerogel was fabricated consisting of quantities of β-SiC_(NW) of15-40 nm in diameter and tens to hundreds of micrometers in *** SiC_(NW) aerogel possessed an ultralow density of 5.82 mg·cm^(-3),high-temperature resistance,and great thermal insulation with its thermal conductivities of0.063 W·m^(-1)·K^(-1) at 100℃ and 0.243 W·m^(-1)·K^(-1) at900℃ in ***,the thermal insulation applicability of this aerogel was *** study provides a promising way for designing and fabricating other multifunctional nanowire aerogels for high-temperature thermal insulation.

关键词： SiC nanowires Aerogel Thermal insulation Thermal conductivity

Sn-doped induced stable 1T-WSe_(2)nanosheets entrenched on N-doped carbon with extraordinary half/full sodium/potassium storage performance

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Rare Metals 2023年第5期42卷 1557-1569页

作者： Yan-Ru liu Ze-Wei Lei Ren-Ping liu xin-ye li Pei-Xun Xiong Yong-Jin Luo Qing-Hua Chen Ming-Deng Wei ling-xing Zeng Qing-Rong Qian College of life Science Fujian Normal UniversityFuzhou350007China Engineering Research Center of Polymer Green Recycling of Ministry of Education College of Environment and ResourcesCollege of Carbon Neutral Modern IndustryFujian Normal UniversityFuzhou350007China Fujian Key Laboratory of Pollution Control and Resource Reuse Fuzhou350007China Fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials Fuzhou UniversityFuzhou350002China Key Laboratory of Advanced Energy Materials Chemistry Ministry of EducationCollege of ChemistryNankai UniversityTianjin300071China

At present,there have been some reports on the application of metal phase selenide(1T-MSe_(2))in the field of energy *** this manuscript,a stable Sn-doped metal phase tungsten selenide(1T-WSe_(2)-Sn)was elaborately fabricated in situ by a simple calcination technique.N-doping was introduced by employing chitosan as precursor and nanoreactor,the Sn-doping induces 1T phase of WSe_(2)and enlarges the layer space to promote the electron/ion transport and structural *** optimized 1T-WSe_(2)-Sn electrode delivers prominent cycling lifespan(285 mAh·g^(-1)at 1.0 A·g^(-1)after 900 cycles)along with decent rate capability when applied as an anode of sodium ion batteries(SIBs).The specific capacity was determined to be of 460 mAh·g^(-1)at 0.1 A·g^(-1)after *** also displays superior capacity of 183 mAh·g^(-1)at0.5 A·g^(-1)for 200 cycles when paired with Na_(3)V_(2)(PO_(4))_(3)*** as the anode for potassium ion batteries(PIBs),it exhibits a satisfactory specific capacity of 345mAh·g^(-1)at 0.1 A·g^(-1)after 50 cycles.

关键词： WSe_(2) Sn-doped Metal phase Sodium/potassium storage

Gold-catalyzed intermolecular amination of allyl azides with ynamides: Efficient construction of 3-azabicyclo[3.1.0] scaffold

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Chinese Chemical Letters 2025年第2期36卷 384-388页

作者： Chong-Yang Shi Jian-xing Gong Zhen li Chao Shu Long-Wu ye Qing Sun Bo Zhou xin-Qi Zhu College of Chemistry and Chemical Engineering Yunnan Normal University Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfacesand College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong University

Gold-catalyzed amination reactions based on azides via α-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules, especially valuable N-heterocycles. However,successful examples of intermolecular generation of α-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides. Herein, we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides, enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex–2-ene derivatives in good to excellent yields with excellent diastereoselectivities. Importantly, this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.

关键词： Alkynes Amination Azides Gold Heterocycles

Thermally activated delayed fluorescence enhanced by macrocyclization

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Science China Chemistry 2025年

作者： Shuo li Chenghao Zhu lijun Mao xin Zhang Zecong ye Chunju li Da Ma School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University School of Chemical Engineering and light Industry Guangdong University of Technology Tianjin Key Laboratory of Structure and Performance for Functional Molecules Tianjin Normal University

Thermally activated delayed fluorescence (TADF) depends on reverse intersystem crossing (RISC) from the lowest triplet to the singlet excited state. Here, a macrocyclization strategy is developed to achieve TADF emission by promoting RISC. 5-(9Hcarbazol-9-yl) isophthalonitrile, a fluorescent molecule, is coupled with 1,4-dimethoxybenzene by methylene bridges to form a macrocycle with TADF emission. Experimental results and theoretical calculation indicate that the macrocyclization strategy contributes to RISC promotion and suppression of nonradiative decay, resulting in effective TADF emission transformed from prompt fluorescence. Three TADF luminophores are cyclized with the same strategy, and an enhanced TADF emission of up to3.8 folds is observed. The marriage of macrocycle chemistry and luminescent materials will provide new guidelines for designing efficient TADF materials.

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High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

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Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi li Yabo Xie Qiancheng Chen xin Zhang Jian-Rong li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

Significant improvement of machinability of C_(f)/SiC composites through matching laser scanning spacing and abrasive belt grain size

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Chinese Journal of Aeronautics 2025年第1期38卷 185-201页

作者： Guijian XIAO Zhengyu YANG Kun ZHOU Yi HE xin li College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China

To improve the application and service of C_(f)/SiC composites as advanced hightemperature structural materials,it is critical to achieve their high-efficiency and low-damage *** this study,the laser-ablating assisted grinding(LAAG)method was presented,and the connection of damage behavior and removal mechanism with laser and grinding processes was *** results demonstrated that the surface of C_(f)/SiC composites after laser ablation was covered with a substantial number of loose oxides primarily composed of *** ablating process,grinding parameter and abrasive belt selection have a significant impact on the machining *** fabricating an ablative layer with small laser scanning spacing,and selecting small abrasive grains and feed rate during grinding,the machinability was improved and a relatively lowerdamage grinding surface could be *** the optimal combination of process parameters,the grinding force and temperature of LAAG could be reduced by up to 85%and 35%,*** this case,the subsurface damage of C_(f)/SiC composites occurred only in the form of microcracks rather large-scale fracture,and the formation of interface debonding and matrix cracking was significantly ***,the grinding chips were mostly shown as micron-sized powders,indicating that the removal mechanism of C_(f)/SiC composites was primarily the microfractured and attrition wear of laser-ablated layer.

关键词： Ceramic matrix composites Laser ablating Grinding Material removal Fracture damage

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： xin li Yibo ZHOU Tao ZHAO xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material CyclingCentre for Research and Education on Biological Evolution and Environment and Frontiers ScienceSchool of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Institute of Palaeontology Yunnan Key Laboratory of Earth System ScienceYunnan Key Laboratory for PalaeobiologyYunnan UniversityKunming650500China

Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the ***,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep *** address this,we conducted taphonomic experiments to simulate the transformation process of black *** changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman *** results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently *** Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature *** the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

Alpha-decay properties of nuclei around neutron magic numbers

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Nuclear Science and Techniques 2025年第1期36卷 140-149页

作者： Ming li Chu-xin Chen Lan-Fang Xiao Yi Zhang Song Luo Xiao-Hua li School of Nuclear Science and Technology University of South ChinaHengyang 421001China PET‑CT Center Chenzhou First People’s HospitalChenzhou 423000China Hengyang Ecological Environment Monitor Center Hengyang 421001China China Certification and Inspection Group Hefei 230000China National Exemplary Base for International Science and Technology Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

By combining experimental α-decay energies and half-lives, the α-particle preformation factor for nuclei around neutron magic numbers N of 126, 152, and 162 were extracted using the two-potential approach. The nuclei around the shell closure were more tightly bound than adjacent nuclei. Additionally, based on the WS4 mass model (Wang et al., Phys. Lett.B 734, 215 (2014)), we extended the two-potential approach to predict the α-decay half-lives of nuclei around N values of178 and 184 with Z of 119 and 120. We believe that our findings will serve as guidelines for future experimental studies.

关键词： adecay Preformation factor Neutron magic number Heavy and superheavy nuclei

Phylogenetic Relationship within Dunaliella （Chlorophyta） inferred from nrDNA ITS Data

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Phylogenetic Relationship within Dunaliella （Chlorophyta） ...