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Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

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Journal of Pharmaceutical Analysis 2024年第3期14卷 295-307页

作者： Xiao-Feng Huang Ying Xue Li Yong tian-tian Wang Pei Luo Lin-Sen Qing Chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China State Key Laboratory for Quality Research in Chinese Medicines Macao University of Science and TechnologyMacaoChina Sichuan Center for Disease Control and Prevention Chengdu610041China University of Chinese Academy of Sciences Beijing100049China

Triterpenoids widely exist in nature,displaying a variety of pharmacological *** triterpenoids in different matrices,especially in biological samples holds great ***-performance liquid chromatography(HPLC)has become the predominant method for triterpenoids analysis due to its exceptional analytical ***,due to the structural similarities among botanical samples,achieving effective separation of each triterpenoid proves challenging,necessitating significant improvements in analytical ***,triterpenoids are characterized by a lack of ultraviolet(UV)absorption groups and chromophores,along with low ionization efficiency in mass ***,routine HPLC analysis suffers from poor *** derivatization emerges as an indispensable technique in HPLC analysis to enhance its *** the structural characteristics of triterpenoids,various derivatization reagents such as acid chlorides,rhodamines,isocyanates,sulfonic esters,and amines have been employed for the derivatization analysis of *** review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of ***,the limitations and challenges encountered in previous studies are discussed,and future research directions are proposed to develop more effective derivatization methods.

关键词： Triterpenoid HPLC Derivatization Quantification

Interfacial tribochemical kinetics: A new perspective on superlubricity of diamond-like carbon films

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Science China(Technological Sciences) 2024年第7期67卷 2050-2052页

作者： CHEN WeiQi MA tian-Bao State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Friction is considered one of the primary challenges affecting the performance of machine operations and is a significant source of energy loss in industrial applications. About 3.%of disposable energy is consumed by ... 详细信息

关键词： kinetics friction operations

Inhibition of Defect-Induced Ice Nucleation, Propagation, and Adhesion by Bioinspired Self-Healing Anti-Icing Coatings

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Research 2024年第1期2023卷 237-246页

作者： Shu tian Ruiqi Li Xinmeng Liu Jiancheng Wang Junyu Yu Sijia Xu Yunqing tian Jing Yang Lei Zhang Department of Biochemical Engineering Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(MOE)School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou CityShandong Province 256606China

Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing ***,the mechanisms of surface-defect-induced icing are *** the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and ***,the ice–defect interlocking structure increases the ice adhesion ***,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is *** coating is based on a design that mimics the ice-binding and non-ice-binding sites in *** enables the coating to markedly inhibit ice nucleation(nucleation temperature3..9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing *** healed coating sustains high anti-icing and deicing performance even under various extreme *** work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.

关键词： coating defect clarified

Growth,optical dispersion and magnetic behavior of Dy^(3.) doped yttrium iron garnet crystals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating Fang Hui Shen Yudie Ma Shijie Liao Shuang Xia tian tian Ding Zhou Yunfeng Ma Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control Materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3.Fe_(5)O_(12)(YIG)crystals are highly desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality single ***^(3.)doping is expected to improve the optical and magneto-optical prope ***,high quality Dy:YIG crystals and the adjustment of Dy^(3.)on the structure and optical behavior of YIG crystal remain unclear,impeding its practical ***,a series of Y_(3.x)Dy_(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3.solid solution crystals was grown by the flux-Bridgman method and single crystals up to 25 mm were *** the introduction of Dy^(3.),lattice parameters are gradually enlarged from 1.23.9 nm(YIG)to 1.2420 nm(DyIG).Typical Dy^(3.)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.3.(500 nm)to 2.10(2500 nm)for YIG crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for DyIG *** optical bandgaps remain almost unchanged for Dy:YIG *** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3.)content,the saturation magnetization(Ms)decreases significantly from 23.62 emu/g(YIG)to 5.3. emu/g(DyIG).Small coercive field is persisted for this system,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical crystals,which is beneficial to the design of high-performance garnet crystals for the application of optical switching and non-reciprocal related devices.

关键词： Magneto-optical crystal Yttrium iron garnet Dy^(3.)doping Crystal growth Optical dispersion Rare earths

CO_(2)flooding in shale oil reservoir with radial borehole fracturing for CO_(2)storage and enhanced oil recovery

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Petroleum Science 2024年第1期21卷 519-534页

作者： Jia-Cheng Dai tian-Yu Wang Jin-Tao Weng Kang-Jian tian Li-Ying Zhu Gen-Sheng Li State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China China National Oil and Gas Exploration and Development Company Limited Beijing100034China

This study introduces a novel method integrating CO_(2)flooding with radial borehole fracturing for enhanced oil recovery and CO_(2)underground storage,a solution to the limited vertical stimulation reservoir volume in horizontal well fracturing.A numerical model is established to investigate the production rate,reservoir pressure field,and CO_(2)saturation distribution corresponding to changing time of CO_(2)flooding with radial borehole fracturing.A sensitivity analysis on the influence of CO_(2)injection location,layer spacing,pressure difference,borehole number,and hydraulic fractures on oil production and CO_(2)storage is *** CO_(2)flooding process is divided into four *** in layer spacing will significantly improve oil production rate and gas storage ***,serious gas channeling can occur when the spacing is lower than 20 *** the pressure difference between the producer and injector,the borehole number,the hydraulic fracture height,and the fracture width can also increase the oil production rate and gas storage *** analysis shows that layer spacing and fracture height greatly influence gas storage and oil *** outcomes are expected to provide a theoretical basis for the efficient development of shale oil reservoirs in the vertical direction.

关键词： Shale oil Radial borehole fracturing Embedded discrete fracture model Enhanced oil recovery Carbon storage

A dynamical neural network approach for distributionally robust chance-constrained Markov decision process

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Science China Mathematics 2024年第6期67卷 1395-1418页

作者： tian Xia Jia Liu Zhiping Chen School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China

In this paper,we study the distributionally robust joint chance-constrained Markov decision *** the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms under the moment-based uncertainty *** cope with the non-convexity and improve the robustness of the solution,we propose a dynamical neural network approach to solve the reformulated optimization *** results on a machine replacement problem demonstrate the efficiency of the proposed dynamical neural network approach when compared with the sequential convex approximation approach.

关键词： Markov decision process chance constraints distributionally robust optimization moment-based ambiguity set dynamical neural network

Supplementation with dimethylglycine sodium salt improves lipid metabolism disorder in intrauterine growth-retarded pigs

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Animal Nutrition 2024年第3期18卷 191-202页

作者： Kaiwen Bai Luyi Jiang tian Wang School of Biological and Chemical Engineering Zhejiang University of Science and TechnologyHangzhou 310023China College of Animal Science and Technology Nanjing Agricultural UniversityNanjing 210095China College of Biology and Environmental Engineering Zhejiang Shuren UniversityHangzhou 310023China Institute of Dairy Science Ministry of Education Key Laboratory of Molecular Animal NutritionCollege of Animal SciencesZhejiang UniversityHangzhou 310023China

This study aims to elucidate the mechanism of lipid metabolism disorder in intrauterine growth retardation(IUGR)pigs and the potential alleviating effects of dimethylglycine sodium salt(DMG-Na).A total of 60 male newborn piglets were selected for this *** each litter,one normal birth weight(NBW)male piglet(1.53.0.04 kg)and two IUGR male piglets(0.76±0.06 kg)were chosen based on their birth *** piglets were divided into three groups for the study:NBW pigs received a PBS gavage and a common basal diet(NBW-C group),IUGR pigs received the same PBS gavage and common basal diet(IUGR-C group),and IUGR pigs received a 70-mg DMG-Na gavage along with a common basal diet supplemented with 0.1%DMG-Na(IUGR-D group).At 150 d of age,all piglets underwent euthanasia by exsanguination following electrical stunning,after which plasma,liver,and longissimus dorsi(LM)samples were promptly *** IUGR-D group demonstrated improvements in plasma parameters(P<0.05),with lower triglyceride and free fatty acid(FFA)values,and hormone levels(P<0.05),with lower growth hormone,insulin,and homeostasis model assessment of insulin resistance *** of lipid metabolism was observed(P<0.05),with lower triglyceride and FFA,and higher hepatic lipase and total lipase values in the liver,and lower triglyceride and FFA values in the *** ETC complexes showed increased levels(P<0.05),including higher complex III values in the liver,and higher complex I,complex III,and complex V values in the *** levels of energy metabolites were noted(P<0.05),with higher NAD^(+),NAD^(+)/NADH,adenosine triphosphate,and mtDNA values,and lower NADH values in the liver and ***,meat quality parameters showed improvement(P<0.05),with higher pH 24 h and a^(*)values,and lower drip loss 48 h,L^(*),and b^(*)*** expressions of lipid metabolism and mitochondrial function-related genes and proteins were upregulated(P<0.05)compared to the IUGR-C *** conclusio

关键词： Intrauterine growth retardation Pig Lipid metabolism Mitochondrial function Dimethylglycine sodium salt

Entanglement dynamics in κ-deformed spacetime

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 33-54页

作者： Xiaobao Liu Zehua tian Jiliang Jing Department of Physics and Electrical Engineering Liupanshui Normal UniversityLiupanshui 553004China School of Physics Hangzhou Normal UniversityHangzhou 311121China CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum *** master equation that governs their evolution is derived by tracing over the degree of freedom of the *** this,we compare the entanglement dynamics of the two atoms moving with different trajectories inκ-deformed and Minkowski ***,when the environment-induced interatomic interaction does not exist,the entanglement dynamics of two static atoms inκ-deformed spacetime are reduced to that in Minkowski spacetime in the case that the spacetime deformation parameterκis sufficiently large as theoretically ***,if the atoms undergo relativistic motion,regardless of whether inertial or non-inertial,their entanglement dynamics inκ-deformed spacetime behave differently from that in Minkowski spacetime even whenκis *** investigate various types of entanglement behavior,such as decay and generation,and discuss how different relativistic motions,such as uniform motion in a straight line and circular motion,amplify the differences in the entanglement dynamics between theκ-deformed and Minkowski spacetime *** addition,when the environment-induced interatomic interaction is considered,we find that it may also enhance the differences in the entanglement dynamics between these two ***,in principle,one can tell whether she/he is inκ-deformed or Minkowski spacetime by checking the entanglement behavior between two atoms in certain circumstances.

关键词： quantum entanglement -deformed spacetime relativistic motion environment-induced interatomic interaction quan-tum field theory in curved spacetime

Acidic electroreduction CO_(2)to formic acid via interfacial modification of Bi nanoparticles at industrial-level current

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Nano Research 2024年第7期17卷 5817-5825页

作者： tian Dong Hongdong Li Zhenhui Wang Yanling Geng Rui Chang Xiaofeng tian Jianping Lai Shouhua Feng Lei Wang Key Laboratory of Eco-Chemical Engineering International Science and Technology Cooperation Base of Eco-Chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection College of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in acidic media is a promising approach to overcome the unavoidable formation of carbonates in alkaline or neutral ***,the proton-rich environment near the catalyst surface favors hydrogen evolution reactions(HER),leading to lower energy efficiency of the desired products,especially in industrial-level current ***,quaternary ammonium cationic surfactant(cetyltrimethylammonium bromide(CTAB))was introduced into acidic electrolyte to modulate the interfacial microenvironment,which greatly enhanced CO_(2)electroreduction to formic acid(HCOOH)at the Bi/C nanoparticles *** a Bi/C nanoparticles electrode with CTAB added,constant production of formic acid was enabled with a cathodic energy efficiency of>40%and maximum FE_(HCOOH)(FE=Faradaic efficiency)of 86.2%at−400 mA·cm^(−2)over 24 *** with in-situ attenuated total reflection Fourier transform infrared spectroscopy,the concentration of*OCHO intermediates significantly increased after CTAB modification,confirming that the hydrophobic interface microenvironment formed by dynamic adsorption of positively charged long alkyl chains on Bi/C nanoparticle electrodes inhibited HER and improved the selectivity of CO_(2)RR to HCOOH.

关键词： acidic media CO_(2)electrolysis electrolyte additive hydrophobic interfacial microenvironment industrial-level current