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Chinese Chemical Letters 2015年第6期26卷 790-792页

作者： De-Long Kong Ye Huang lai-yang ren Wen-Hua Feng Department of New Drug Research and Development Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College

Bedaquiline is a new medicine for pulmonary multi-drug resistant tuberculosis （MDR-TB）, which is a pure enantiomer with two chiral centers. The current industrial preparation process requires the separation of active Bedaquiline from a mixture of four isomers. Obviously, direct dispose of the other three undesired stereoisomers will cause significant waste and increase the unnecessary cost of production. Here, we developed an efficient, facile and scalable process for recycling the inactive stereoisomers of Bedaquiline. All these inactive stereoisomers could be recycled by their conversion to two important intermediates in the Bedaquiline synthesis via a base-catalyzed Csp3-Csp3 bond cleavage of a benzyl alcohol intermediate. And the precise conditions and mechanism of the base-catalyzed cleavage reaction were discussed.

关键词： Bedaquiline Inactive stereoisomers RecycleCsp3-Csp3 cleavage

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基于众包的维吾尔语多源语义知识库构建研究

计算机应用与软件 2018年第8期35卷 137-142,225页

作者：赖茹杨勇任鸽新疆师范大学计算机科学技术学院新疆乌鲁木齐830054

为有效解决目前维吾尔语的语义知识库构建中存在的专家构建周期长、工作量大且难以动态更新等问题,提出基于众包的维吾尔语多源语义知识库平台的构建。该平台集词条创建、词条审核、任务管理等功能为一体,利用基于互联网用户协作的众包... 详细信息

为有效解决目前维吾尔语的语义知识库构建中存在的专家构建周期长、工作量大且难以动态更新等问题,提出基于众包的维吾尔语多源语义知识库平台的构建。该平台集词条创建、词条审核、任务管理等功能为一体,利用基于互联网用户协作的众包方式,融合维吾尔语词典与语料库的语义资源,构建大规模、开放式的维吾尔语多源语义知识库。在充分研究众包模式及其发展现状后,对众包平台构建中质量控制、激励机制关键问题进行探讨,提出平台的设计思路与框架,并进一步实现了基于众包的维吾尔语多源语义知识库平台。实例表明,该平台为维吾尔语的语义知识库构建提供了一种全新的方法,且能有效解决知识库的实时更新问题。

关键词：众包维吾尔语语义知识库质量控制激励机制

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying Lu Linqiang Tian Sanqiao Yao Feng lai yangfan Liang Chuanchuan Liu Yujia Lu Sijia Tian Yanmei Zhao Wenjie ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

(NH_4)_2HPO_4-NH_3·H_2O-H_2O系APT溶解度研究

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稀有金属与硬质合金 2016年第5期44卷 6-10页

作者：万林生金先文赖星任杨亮刘鹏梁勇江西理工大学冶金与化学工程学院江西赣州341000 崇义章源钨业股份有限公司江西崇义341300 赣州海创钨业有限公司江西大余341200 钨资源高效开发及应用技术教育部工程研究中心江西赣州341000

采用溶解平衡法研究了(NH_4)_2HPO_4-NH_3·H_2O-H_2O系APT的溶解性能。随着氨水浓度增大,APT溶解度由略微下降转为较快上升,溶液中磷钨杂多酸浓度大幅降低,而同多钨酸根和正钨酸根浓度大幅升高。相同磷酸氢二铵浓度下(NH_4)_2HPO_4-NH_... 详细信息

采用溶解平衡法研究了(NH_4)_2HPO_4-NH_3·H_2O-H_2O系APT的溶解性能。随着氨水浓度增大,APT溶解度由略微下降转为较快上升,溶液中磷钨杂多酸浓度大幅降低,而同多钨酸根和正钨酸根浓度大幅升高。相同磷酸氢二铵浓度下(NH_4)_2HPO_4-NH_3·H_2O-H_2O系APT溶解度远大于(NH_4)_2HPO_4-H_2O系。

关键词：仲钨酸铵(APT) 磷酸氢二铵氨水溶解性能磷钨杂多酸溶解平衡法

Cellulose nanofiber-derived carbon aerogel for advanced room-temperature sodium–sulfur batteries

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Carbon Energy 2023年第1期5卷 1-15页

作者： Wu yang Wang yang ren Zou Yongfa Huang Haihong lai Zehong Chen Xinwen Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhouChina

Room-temperature sodium–sulfur(RT/Na–S)batteries are regarded as promising large-scale stationary energy storage systems owing to their high energy density and low cost as well as the earth-abundant reserves of sodium and ***,the diffusion of polysulfides and sluggish kinetics of conversion reactions are still major challenges for their ***,we developed a powerful and functional separator to inhibit the shuttle effect by coating a lightweight three-dimensional cellulose nanofiber-derived carbon aerogel on a glass fiber separator(denoted NSCA@GF).The hierarchical porous structures,favorable electronic conductivity,and three-dimensional interconnected network of N,S-codoped carbon aerogel endow a multifunctional separator with strong polysulfide anchoring capability and fast reaction kinetics of polysulfide conversion,which can act as the barrier layer and an expanded current collector to increase sulfur ***,the hetero-doped N/S sites are believed to strengthen polysulfide anchoring capability via chemisorption and accelerate the redox kinetics of polysulfide conversion,which is confirmed from experimental and theoretical *** a result,the assembled Na–S coin cells with the NSCA@GF separator showed a high reversible capacity(788.8 mAh g^(−1) at 0.1 C after 100 cycles)and superior cycling stability(only 0.059%capacity decay per cycle over 1000 cycles at 1 C),thereby demonstrating the significant potential for application in high-performance RT/Na–S batteries.

关键词： carbon aerogel cellulose nanofiber N,S codoping redox kinetics sodium–sulfur batteries

The first N-ligand assisted Pd catalyzed asymmetric synthesis of 3-arylsuccinimides as novel antifungal leads

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Organic Chemistry Frontiers 2022年第1期9卷 183-189页

作者： Jixing lai Juan yang Chen yang renéCsuk Baoan Song Shengkun Li Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang 550025China Organic Chemistry Martin-Luther-University Halle-WittenbergKurt-Mothes-Str.2D-06120 Halle(Saale)Germany

The first palladium/chiral nitrogenous ligand-catalyzed enantioselective addition of aryl boronic acids to various maleimides was *** protocol features mild conditions combined with good functional group *** resultant 3-arylsuccinimides were shown to be novel chiral antifungal leads and inspired the discovery of novel ligands to address the challenging issues of this transformation.

关键词： catalyzed chiral palladium

Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Polymer Science 2024年第9期42卷 1353-1359,I0007页

作者： Ye-Peng Qiao Chun-lai ren National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underlying the relaxation process remains insufficiently *** we employed MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously,with intramolecular stress release happening abruptly only when the DNA chain traverses the breakage *** relaxation process is influenced not only by the separation distance between the fixed ends but also their ***,we observe an inhibitory effect on the relaxation characterized by small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

Optimization of the cavity beam-position monitor system for the Shanghai soft X-ray free-electron laser user facility

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Nuclear Science and Techniques 2022年第10期33卷 22-32页

作者： Jian Chen Yong-Bin Leng Lu-yang Yu Long-Wei lai ren-Xian Yuan Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

To achieve high-efficiency operation of the highgain free-electron laser(FEL),the electron beams and radiated photon beams need to be overlapped precisely and pass through the entire undulator ***,a high-resolution beam-position monitor(BPM)is required.A cavity BPM(CBPM)with a resonant cavity structure was developed and used in the Shanghai Soft X-ray FEL(SXFEL)test facility and can achieve a position resolution of<1μ*** construction and operation of the SXFEL user facility also bring about higher requirements for beamposition *** this case,the factors that affect the performance of the CBPM system were further *** included the amplitude and phase stability of the local oscillator,stability of the trigger signal,performance of the radio frequency front-end,signal processing electronics,and signal processing *** on the upgrade and optimization of the system,a beam test platform was built at the end of the linear acceleration section of the SXFEL,and the experimental results show that the position resolution of the system can reach 177 nm at a bunch charge of 500 pC,and the dynamic range is controlled within±300μm,and the relative measurement uncertainty of the bunch charge can reach 0.021%,which are significant improvements compared to the attributes of the previous system.

关键词： Cavity BPM SXFEL System optimization Position resolution Measurement uncertainty Algorithm

Rotating Massive Strangeon Stars and X-Ray Plateau of Short GRBs

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Research in Astronomy and Astrophysics 2024年第3期24卷 47-57页

作者： Xi-Yan yang Xiao-Yu lai Wei-Wei Tan ren-Xin Xu School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhou 434023China Research Center for Astronomy Hubei University of EducationWuhan 4300205China Key Laboratory of Quark and Lepton Physics Central China Normal UniversityMinistry of EducationWuhan 430079China School of Physics Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Strangeon stars,which are proposed to describe the nature of pulsar-like compact stars,have passed various observational *** maximum mass of a non-rotating strangeon star could be high,which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon *** study rigidly rotating strangeon stars in the slowly rotating approximation,using the Lennard-Jones model for the equation of *** can significantly increase the maximum mass of strangeon stars with unchanged baryon numbers,enlarging the mass-range of long-lived strangeon *** spin-down after merger,the decrease of radius of the remnant will lead to the release of gravitational *** into account the efficiency of converting the gravitational energy luminosity to the observed X-ray luminosity,we find that the gravitational energy could provide an alternative energy source for the plateau emission of X-ray *** fitting results of X-ray plateau emission of some short gamma-ray bursts suggest that the magnetic dipole field strength of the remnants can be much smaller than that of expected when the plateau emission is powered only by spin-down luminosity of magnetars.

关键词： dense matter-(stars) pulsars general-(stars) gamma-ray burst general

Low-loss, dual-polarization asymmetric Mach-Zehnder interferometer chips for quantum key distribution

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Science China(Information Sciences) 2023年第8期66卷 45-51页

作者： Meizhen ren lai ZHOU Zhiliang YUAN Beijing Academy of Quantum Information Sciences

We have developed the first low-loss, dual-polarization, asymmetric Mach-Zehnder interferometer(AMZI) chip for phase-coding quantum key distribution(QKD) using silica planar lightwave circuit technology. The transmitter and receiver modules have a polarization extinction ratio greater than 20 and15 d B, respectively. Using a birefringent Mach-Zehnder interferometer, a polarization beam splitter is integrated into the receiver chip, while the polarization rotation function is obtained via a half-wave plate thin film. The receiver chip is entirely passive and has an excellent fiber C fiber loss of 1.90 d B, while the transmitter’s AMZI contains thermo-optical electrodes for adjusting the output pulses’ relative phase and intensity ratio. The chips are evaluated to have an interference visibility of greater than 98% across a broad temperature range, demonstrating their suitability for quantum key distribution applications.

关键词： quantum key distribution dual-polarization asymmetric Mach-Zehnder interferometer polarization beam splitter silica-based planar lightwave circuit technology