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Practical Synthesis of Valbenazine via 1,3-Dipolar Cycloaddition

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Chinese Journal of Chemistry 2024年第8期42卷 841-845页

作者： Yalan peng Zuming Lin Lili Zhu Shiqing Han Sha-Hua Huang Ran hong College of Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjingJiangsu211816 China School of Environmental and Chemical Engineering Shanghai Institute of TechnologyShanghai201418 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China Innovation Research Institute of Traditional Chinese Medicine(IRI) Shanghai University of Traditional Chinese Medicine1200 Cailun RoadShanghai201203 China

Comprehensive Summary,Valbenazine(Ingrezza),a potent and highly selective inhibitor of vesicular monoamine transporter type 2(VMAT2)through the active metabolite hydrotetrabenazine(HTBZ),has been approved for the treatment of tardive dyskinesia and,very recently,for chorea,which is associated with Huntington's *** numerous synthetic efforts dedicated to the synthesis of HTBZ,the industrial preparation of valbenazine uses dihydroisoquinoline as a starting material and the chiral resolution of racemic HTBZ derived from ketone ***,we present a practical synthesis of HTBZ and valbenazine featuring a highly stereoselective 1,3-dipolar cycloaddition and enzymatic kinetic *** cascade process includes cycloaddition,N—O bond cleavage,and lactamization,which proved to be operationally *** allure of the enzymatic resolution developed in this work offers a rapid access toward affording tetrahydroisoquinoline(THIQ)-fused piperidine in the production of medically significant compounds,such as yohimbine and reserpine.

关键词： Cycloaddition Chemoenzymatic Kinetic resolution Prodrugs VMAT2 inhibitor

Sparse Reconstructive Evidential Clustering for Multi-View Data

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 459-473页

作者： Chaoyu Gong Yang you School of Computing National University of SingaporeSingapore

Although many multi-view clustering(MVC) algorithms with acceptable performances have been presented, to the best of our knowledge, nearly all of them need to be fed with the correct number of clusters. In addition, these existing algorithms create only the hard and fuzzy partitions for multi-view objects,which are often located in highly-overlapping areas of multi-view feature space. The adoption of hard and fuzzy partition ignores the ambiguity and uncertainty in the assignment of objects, likely leading to performance degradation. To address these issues, we propose a novel sparse reconstructive multi-view evidential clustering algorithm(SRMVEC). Based on a sparse reconstructive procedure, SRMVEC learns a shared affinity matrix across views, and maps multi-view objects to a 2-dimensional humanreadable chart by calculating 2 newly defined mathematical metrics for each object. From this chart, users can detect the number of clusters and select several objects existing in the dataset as cluster centers. Then, SRMVEC derives a credal partition under the framework of evidence theory, improving the fault tolerance of clustering. Ablation studies show the benefits of adopting the sparse reconstructive procedure and evidence theory. Besides,SRMVEC delivers effectiveness on benchmark datasets by outperforming some state-of-the-art methods.

关键词： Evidence theory multi-view clustering(MVC) optimization sparse reconstruction

Non-Deterministic Liveness-Enforcing Supervisor Tolerant to Sensor-Reading Modification Attacks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 240-248页

作者： Dan you Shouguang Wang IEEE the School of Information and Electronic Engineering Sussex Artificial Intelligence InstituteZhejiang Gongshang UniversityHangzhou 310018China

In this paper, we study the supervisory control problem of discrete event systems assuming that cyber-attacks might occur. In particular, we focus on the problem of liveness enforcement and consider a sensor-reading modification attack(SM-attack) that may disguise the occurrence of an event as that of another event by intruding sensor communication channels. To solve the problem, we introduce non-deterministic supervisors in the paper, which associate to every observed sequence a set of possible control actions offline and choose a control action from the set randomly online to control the system. Specifically, given a bounded Petri net(PN) as the reference formalism and an SMattack, an algorithm that synthesizes a liveness-enforcing nondeterministic supervisor tolerant to the SM-attack is proposed for the first time.

关键词： Cyber-attacks cyber-physical system(CPS) liveness non-deterministic supervisors Petri net(PN)

In situ plasmonic & electrochemical fiber-optic sensor for multi-metal-ions detection

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Science China(Information Sciences) 2024年第1期67卷 292-302页

作者： Xiaoling peng Zhiyong YANG Bo peng Zhi LI Zhicong REN Xicheng WANG Jiahai LI Zhencheng LI Liang CHEN Daotong you Kaiwei LI Jianqing LI Tuan GUO Institute of Photonics Technology Jinan University School of Computer Science and Engineering Macau University of Science and Technology Institute for Environmental and Climate Research Jinan University Key Laboratory of Bionic Engineering of Ministry of Education Jilin University

High precision and high throughput detection of heavy metal ions is essential for water quality monitoring and ***,we propose a plasmonic & electrochemical dual-mode fiber sensing probe for label-free and real-time detection of multiple ions(Pb2+and Cu2+as examples).This sensor comprises a multimode fiber-single mode fiber reflection probe,the outer surface of which is coated with a gold nanofilm to excite the surface plasmon resonance(SPR) optically and simultaneously serves as an electrochemical working *** traditional electrochemical detection,the enrichment of ions cannot be detected in ***,by utilizing the plasmonic & electrochemical dual-mode detection method,various kinds of metal ions can be deposited onto the gold nanofilm and selectively oxidized during forward potential scanning,and the entire electrochemical process can be monitored by SPR *** experimentally demonstrate that the sensor can simultaneously detect Pb2+and Cu2+in a mixed solution in real-time,providing a linear response over the ion concentration range from 10-12to 10-7M and offering an excellent detection limit(1.69×10-14–5.49×10-13M).The proposed dual-mode fiber sensor has the benefits of remote sensing,compact footprint,and cost-effectiveness and shows excellent potential for water quality risk management in difficult-to-reach environments.

关键词： optical fiber sensor surface plasmon resonance electrochemical measurement ions detection water pollution

Formation of free-surface vortex and vortex suppression by rotating stopper-rod at end of tundish casting

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Journal of Iron and Steel Research International 2024年第5期31卷 1104-1116页

作者： Qing Fang peng Zhao Hua Zhang Wen-hao Zhou Gang Yu Jia-hui Wang hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina

A rotating stopper-rod technique was proposed to suppress the formation of free-surface vortex in the *** large eddy simulation model coupled with volume of fluid model was developed to study the steel–slag–gas three-phase flow *** critical slag entrapment height of the free-surface vortex and mass of residual steel were predicted at different rotating speeds(30,60,90 and 120 r/min)of the rotating *** numerical model was verified by water model *** results showed that by rotating the stopper-rod in the opposite direction of the vortex above the submerged entry nozzle,the formation of vortex can be effectively disturbed and the critical height of the free-surface vortex can be *** for the 2nd strand,when the rotating speeds are 30,60,90 and 120 r/min,the critical height of the free-surface vortex above the 2nd strand is 7.3,4.7,6.3 and 7.4 cm,respectively.A reasonable rotating speed should be 60 r/min,which can reduce about 2 tons of residual *** rotating speeds just can reduce about 1.6 tons of residual steel.

关键词： Tundish Free-surface vortex Stopper-rod Numerical simulation Multiphase flow

Theoretical study on the synergistic mechanism of Fe–Mn in sodium-ion batteries

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Particuology 2024年第10期93卷 284-290页

作者： Yang you Mingliang Yuan School of Mineral Processing and Bioengineering Central South UniversityChangsha410083China

This article conducts first-principles calculations to initially explore the construction of two configurations,NaFeO_(2)(NFO)and NaMnO_(2)(NMO),and studies the mixing enthalpies under different Fe–Mn *** results indicate that NaFe3/8Mn5/8O_(2)(NFMO)exhibits the most thermodynamically stable *** calculations on the mixing enthalpies and volume changes during the sodium extraction process for NFO,NMO,and NFMO configurations are presented,along with the partial density of states(PDOS)and Bader charges of transition metals(TM)and *** calculations reveal the synergistic mechanism of Fe and *** and Mn can engage in more complex electron exchanges during sodium extraction,optimizing the internal electron density distribution and overall charge balance,thereby stabilizing the crystal structure and reducing the migration of Fe^(3+)to the sodium layers during deep sodium *** interaction between Fe’s 3d electrons and Mn’s 3d electrons through the shared oxygen atoms’2p orbitals occurs in the Fe–Mn–O *** interaction can lead to a rebalancing of the electron density around Mn³⁺atoms,mitigating the asymmetric electron density distribution caused by the d4 configuration of the lone Mn³⁺and suppressing the Jahn-Teller effect of Mn^(3+).Moreover,the synergistic effects between Fe and Mn can provide a more balanced charge distribution,reducing extreme changes to the charge state of oxygen atoms and decreasing the irreversible oxygen release caused by anionic redox reactions during deep sodium extraction,thereby enhancing the material’s *** in-depth study of the interaction mechanism at the microscopic level when co-doping Fe and Mn offers valuable insights for the rational design and development of high-performance cathode materials.

关键词： First-principles calculations Sodium-ionbatteries Layered oxides NaFe_(3/8)Mn_(3/8)O_(2)

Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir

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Petroleum Science 2024年第2期21卷 1018-1031页

作者： Hao-Chuan Zhang Yong Tang you-Wei He Yong Qin Jian-hong Luo Yu Sun Ning Wang De-Qiang Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina CNPC Research Institute of Petroleum Exploration&Development Beijing100083China Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina State Key Laboratory of Offshore Oil Exploitation CNOOC Research Institute Co.LtdBeijing100027China

The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture ***, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks.

关键词： Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： peng He Meng-Yang Hu Jin-hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Magnetic field imaging with radio-frequency optically pumped magnetometers [Invited]

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Chinese Optics Letters 2024年第6期22卷 38-45页

作者： Xiyu Liu Junlong Han Wei Xiao Teng Wu Xiang peng hong Guo School of Electronics Peking UniversityBeijing 100871China

High-sensitivity radio-frequency optically pumped magnetometers (RF-OPMs), working without cryogenic condition, play a critical role in magnetic field imaging(MFI) at low frequencies(e.g., 100 Hz to 1 MHz). We introduce the principle of operation and recent developments of RF-OPMs and focus on reviewing the MFI applications in magnetic induction tomography, ultralow-field magnetic resonance imaging, and magnetic particle imaging. For the applications of RF-OPMs, ranging from industrial monitoring to medical imaging and security screening, the unshielded and portable RF-OPMs(and RF-OPM array)techniques are still under the further development for detecting and scanning over the target object for accomplishing the final three-dimensional imaging, and thus extremely require the abilities of active compensation of the ambient magnetic field and sensor miniaturization in the future.

关键词： magnetic field imaging radio frequency optically pumped magnetometer