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有机化学 2004年第Z1期24卷 31-32页

作者： YU,An-Guang WANG,Nai-Xing ZHANG,Jun-Ping YANG,Yun-Xu WANG,Wu-Wei sheng,rui-long Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100101

Benzopyran compounds possess diverse pharmacological properties such as β-blockade, anticonvulsant and antimicrobial.[1,2] Our interest has been focused on the synthesis of 1-[6-Fluoro-2S]-3H,4H-dihydro-2H-2-chromenyl]-(1R)-1,2-ethanediol (6) and 1-[6-fluoro-(2R)-3H,4H-dihydro-2H-2-chromenyl]-(1R)-1,2-ethanediol (7) which are particularly convenient precursor to (S,R,R,R)-NE (8). 8 containing four asymmetrical carbon atoms was reported to be the most active isomer.[3] Chandrasekhar[4] has reported on the synthesis of 8. The key step to synthesize this compound is to obtain the chiral chromanone 6 and 7. 6 was accomplished in 8 steps by the Clasien rearrangement and a one-pot Sharpless asymmetric epoxidation, but the compound 7 was accomplished in 10 steps. Johannes[5] used Zr-catalytic kinetic resolution of allylic ethers and Mo-catalyzed chromene formation to synthesize 8 in 14 steps. However both of the methods request many synthetic steps and expensive reagents.……

关键词： asymmetric epoxidation kinetic resolution

Energy flux and waveform of gravitational wave generated by coalescing slow-spinning binary system in effective one-body theory

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 73-83页

作者： Weike Deng sheng long Jiliang Jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory to include binary systems with slowly spinning black ***,we decompose the equation for the null tetrad component of the gravitationally perturbed Weyl tensorψ_4~B into radial and angular parts,leveraging the second-order approximation of the rotation parameter ***,we derive an analytical solution for the radial equation and observe that our results are contingent upon the parameters a_(2),a_(3),and a,which represent the second-and third-order correction parameters,***,we calculate the energy flux,the radiation-reaction force and the waveform for the“plus”and“cross”modes of the gravitational waves generated by merging slowly spinning binary black holes.

关键词： post-Minkowskian approximation effective-one-body theory gravitational waveform template

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Energy flux and waveforms by coalescing spinless binary system in effective one-body theory

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 58-68页

作者： sheng long Weike Deng Jiliang Jing 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 Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We present a study on the energy radiation rate and waveforms of the gravitational wave generated by coalescing spinless binary systems up to the third post-Minkowskian approximation in the effective one-body *** derive an analytical expansion of the null tetrad components of the gravitational perturbed Weyl tensorΨ4in the effective spacetime,we utilize the method proposed by Sasaki et *** this investigation,we discover more general integral formulas that provide a theoretical framework for computing the results in any ***,we successfully compute the energy radiation rate and waveforms of the gravitational wave,which include the results of the Schwarzschild case and the correction terms resulting from the dimensionless parameters a2and a3in the effective metric.

关键词： post-Minkowskian approximation effective one-body theory gravitational waveform template

Narrowband blue emitter based on fused nitrogen/carbonyl combination with external quantum efficiency approaching 30%

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Science China Chemistry 2024年第1期67卷 351-359页

作者： long Chen Jia-Heng Cai You-Jun Yu Yang-Kun Qu sheng-Yi Yang sheng-Nan Zou rui-Hong Liu Dong-Ying Zhou Liang-sheng Liao Zuo-Quan Jiang Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyMacao 999078China

Multi-resonance thermally activated delayed fluorescence(MR-TADF)emitters can enable narrowband emission with high color purity and electroluminescence ***/carbonyl(N/C=O)system is receiving increasing attention while the nitrogen/boron(N/B)system has been widely *** decoration is an effective approach for N/B type MR-TADF system but always leads to broadening and red-shifting of the emission band in N/C=O MR-TADF *** attribute these unfavorable phenomena to the formation of intramolecular charge transfer between the MR-core and peripheral *** address this issue,we have developed a new strategy by decorating DMQAO(a fused N/C=O MR-core)with a triazine acceptor and a neutral terphenyl group to construct MTDMQAO and MBDMQAO,*** introduction of the triazine acceptor not only realizes efficient narrowband emission in MTDMQAO,but also accelerates the reverse intersystem crossing process through enhanced spin-orbital *** a result,MTDMQAO exhibits a significantly higher external quantum efficiency of 29.4%compared to the referent emitters,validating the rationality of our derivation *** study highlights the potential of the N/C=O system for MR-TADF emitters and provides important insights for understanding the difference between N/B and N/C=O systems.

关键词： carbonyl group narrowband acceptor decoration thermally activated delayed fluorescence OLEDs

Effects of oral probiotics on inflammation and intestinal function in adult patients after appendectomy:Randomized controlled trial

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1371-1376页

作者： Ke Lan Ke-rui Zeng Fu-rui Zhong sheng-Jin Tu Jin-long Luo Shi-long Shu Xue-Feng Peng Hua Yang Kai Lu Department of General Surgery Zigong Fourth People's HospitalZigong 643000Sichuan ProvinceChina

BACKGROUND Appendectomy is an acute abdominal surgery that is often accompanied by severe abdominal *** probiotics are one of the postoperative treatments for rapid ***,there is a lack of prospective studies on this topic after *** To investigate whether the postoperative probiotics can modulate the inflammatory response and restore intestinal function in patients following *** This was a prospective,randomized trial.A total of 60 emergency patients were randomly divided into a control group(n=30)and a probiotic group(n=30).Patients in the control group started to drink some water the first day after surgery,and those in the probiotic group were given water supplemented with Bacillus licheniformis capsules for 5 consecutive days *** indices of inflammation and postoperative conditions were recorded,and the data were analyzed with RStudio 4.3.2 *** A total of 60 participants were *** with those in the control group,the C-reactive protein(CRP),interleukin 6 and procalcitonin(PCT)levels were significantly lower in the probiotic group at 2 d after surgery(P=2.224e-05,P=0.037,and P=0.002,respectively,all P<0.05).This trend persisted at day 5 post-surgery,with CRP and PCT levels remaining significantly lower in the probiotic group(P=0.001 and P=0.043,both P<0.05).Furthermore,probiotics0.028,both P<0.05).CONCLUSION Postoperative oral administration of probiotics may modulate the gut microbiota,benefit the recovery of the early inflammatory response,and subsequently enhance recovery after appendectomy.

关键词： Probiotics Gut microbiota Appendectomy Inflammatory markers Intestinal function Enhanced recovery after surgery Postsurgical infections

Disparity estimation for multi-scale multi-sensor fusion

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Journal of Systems Engineering and Electronics 2024年第2期35卷 259-274页

作者： SUN Guoliang PEI Shanshan long Qian ZHENG Sifa YANG rui Suzhou Automotive Research Institute Tsinghua UniversitySuzhou 215000China Beijing Smarter Eye Technology Co. Ltd.Beijing 100023China College of Artifical Intelligence Tianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Department of Precision Instrument Tsinghua UniversityBeijing 100084China

The perception module of advanced driver assistance systems plays a vital *** schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection *** paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme.A binocular stereo vision sensor composed of two cameras and a light deterction and ranging(LiDAR)sensor is used to jointly perceive the environment,and a multi-scale fusion scheme is employed to improve the accuracy of the disparity *** solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR *** demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation.

关键词： stereo vision light deterction and ranging(LiDAR) multi-sensor fusion multi-scale fusion disparity map

An analytical model to estimate the time delay to reach spontaneous ignition considering heat loss in oil reservoirs

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Petroleum Science 2024年第4期21卷 2469-2474页

作者： James J.sheng Er-long Yang College of Petroleum Engineering Northeast Petroleum University

During air injection into an oil reservoir, an oxidation reaction generates some heat to raise the reservoir temperature. When the reservoir temperature reaches an ignition temperature, spontaneous ignition occurs. There is a time delay from the injection to ignition. There are mixed results regarding the feasibility of spontaneous ignition in real-field projects and in laboratory experiments. No analytical model is available in the literature to estimate the oxidation time required to reach spontaneous ignition with heat *** paper discusses the feasibility of spontaneous ignition from theoretical points and experimental and field project observations. An analytical model considering heat loss is proposed. Analytical models with and without heat loss investigate the factors that affect spontaneous ignition. Based on the discussion and investigations, we find that it is more difficult for spontaneous ignition to occur in laboratory experiments than in oil reservoirs; spontaneous ignition is strongly affected by the initial reservoir temperature, oil activity, and heat loss; spontaneous ignition is only possible when the initial reservoir temperature is high, the oil oxidation rate is high, and the heat loss is low.

关键词： Spontaneous ignition Time delay Air injection Heat loss Low temperature oxidation Combustion

A Catalog of ^(13)CO Clumps from the MWISP in l=10°–20°

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Research in Astronomy and Astrophysics 2024年第5期24卷 218-234页

作者： Xiaoyu Luo sheng Zheng Zhibo Jiang Zhiwei Chen Yao Huang Shuguang Zeng Xiangyun Zeng rui Zhang Chen long Guangrong Zhou Jinbo Hu Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443000China College of Electrical Engineering and New Energy China Three Gorges UniversityYichang 443000China College of Science China Three Gorges UniversityYichang 443000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

In this study, we present a catalog of molecular clumps extracted from ^(13)CO(J=1-0) emission data of the Milky Way Imaging Scroll Painting(MWISP) project. The data covers the inner Milky Way within the longitude range10°≤l≤20° and the latitude strip of |b|≤ 5°. 25. The workflow for the extraction of clumps, namely Facet-SS-3DClump, consists of two parts: the identification of clump candidates and their verification. First, Facet-SS-3DClump employs FacetClumps to identify clump candidates. Subsequently, high-confidence clumps are obtained by cross-matching with the clumps detected by other algorithms, such as dendrogram. Second, these high-confidence clumps are used as prior knowledge to train a semi-supervised deep clustering approach, SS-3D-Clump, which is applied to verify clump candidates detected by FacetClumps, providing confidence levels for the molecular clumps. Finally, the catalog comprising 18,757 molecular clumps was obtained using Facet-SS-3D-Clump, and the catalog is 90% complete above 37 K km s^(-1). We observe a significant deviation of the mean Galactic latitude for clumps within |b|≤ 2° from the midplane, with b=-0°.110. We found that 82.3% of the dust clumps correspond to ^(13)CO clumps by matching with Herschel infrared dust clumps. In the future, Facet-SS-3D-Clump will be applied to detect ^(13)CO clumps in the entire MWISP data.

关键词： ISM molecules methods data analysis-stars formation

The Multiple Roles of Autophagy in Neural Function and Diseases

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Neuroscience Bulletin 2024年第3期40卷 363-382页

作者： Yan-Yan Li Zheng-Hong Qin rui sheng Department of Pharmacology and Laboratory of Aging and Nervous Diseases Jiangsu Key laboratory of Neuropsychiatric DiseasesCollege of Pharmaceutical Sciences of Soochow UniversitySuzhou 215123China

Autophagy involves the sequestration and delivery of cytoplasmic materials to lysosomes,where proteins,lipids,and organelles are degraded and *** to the way the cytoplasmic components are engulfed,autophagy can be divided into macroautophagy,microautophagy,and chaperone-mediated ***,many studies have found that autophagy plays an important role in neurological diseases,including Alzheimer's disease,Parkinson's disease,Huntington's disease,neuronal excitotoxicity,and cerebral *** maintains cell homeostasis in the nervous system via degradation of misfolded proteins,elimination of damaged organelles,and regulation of apoptosis and ***-mTOR,Beclin 1,TP53,endoplasmic reticulum stress,and other signal pathways are involved in the regulation of autophagy and can be used as potential therapeutic targets for neurological ***,we discuss the role,functions,and signal pathways of autophagy in neurological diseases,which will shed light on the pathogenic mechanisms of neurological diseases and suggest novel targets for therapies.

关键词： Autophagy Neurodegenerative diseases Cerebral ischemia AMPK mTOR Beclin 1 TP53 Endoplasmic reticulum stress

Neurotoxicity of tetramethylammonium ion on larval and juvenile zebrafish:Effects on neurobehaviors and multiple biomarkers

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Journal of Environmental Sciences 2024年第9期143卷 138-147页

作者： ruixin Zhang rui Wang Jiajun Chang GDaniel sheng Daqiang Yin Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Tetramethylammonium hydroxide(TMAH)is an important compound that utilized and released by the rapidly expanding semiconductor industry,which could hardly be removed by the conventional wastewater treatment *** a cholinergic agonist,the tetramethylammonium ion(TMA^(+))has been reported to induce toxicity to muscular and respiratory systems of mammals and human,however the toxicity on aquatic biota remains poorly *** investigated the neurotoxic effects of TMA^(+)exposure on zebrafish,based on neurobehavior tests and a series of *** inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L,and significant alterations on swimming path angles(straight and deflective movements)occurred even at 10 mg/*** tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species(ROS)and malondialdehyde(MDA),significantly negatively related with the activities of antioxidant enzymes,but not significantly correlated with the level of acetylcholinesterase(AChE).Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress,rather than the alterations of *** the highest exposure concentration(200 mg/L),TMA^(+)evoked more severe toxicity on zebrafish juveniles,showing significantly stronger elevation on the MDA activity,and greater inhibitions on the activities of antioxidant enzymes and ACh E,suggesting juveniles were more susceptible to TMA^(+)exposure than larval zebrafish.

关键词： Tetramethylammonium Zebrafish Oxidative stress Acetylcholinesterase Neurobehavior