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Chinese Chemical Letters 2022年第9期33卷 4303-4305页

作者： Huan Liu zhong-jian cai Shun-Jun Ji Key Laboratory of Organic Synthesis of jiangsu Province College of ChemistryChemical Engineering and Materials Science&Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhou 215123China

Herein,we reported a convenient and efficient multicomponent reaction of indoles,selenium powder and unactivated alkyl halides.This protocol provides a practical,and facile approach for the synthesis of 3-alkylselenindole derivatives.The advantages of this strategy include mild and transition-metal-free conditions,broad functional group tolerance,the use of simple and easily accessible seleniium powder and alkyl halides as coupling partners.More importantly,the reaction proceeded smoothly with a large scale(>10 g,>90%yield),which further highlighted the potential application of this selenation strategy.

关键词： Selenium 3-Alkylselenindole Indole Selenization

Rhodium-Catalyzed Pyridine-Assisted C-H Arylation for the Synthesis of Planar Chiral Ferrocenes

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CCS Chemistry 2020年第6期2卷 642-651页

作者： Chen-Xu Liu zhong-jian cai Qiang Wang Zhi-Jie Wu Qing Gu Shu-Li You State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032

Planar chiral ferrocenes are widely applied in organic synthesis,materials science,and medicinal chemistry,but their synthesis is not trivial.Herein,a highly efficient synthesis of planar chiral ferrocene-based pyridine derivatives via Rh(I)-catalyzed direct coupling of pyridylferrocenes with aryl halides was developed.Good yields and excellent enantioselectivity(95–>99%ee)are obtained for a wide range of substrates.The compatibility of gram-scale synthesis and relatively low catalyst loading(down to 1 mol%based on[Rh])enhance the practicality of the current method.The generated coupling products can be readily transformed into chiral ligands.Mechanistic studies suggest that the C–H bond cleavage of pyridylferrocene may be a reversible step and not the rate-determining step.Significant nonlinear effects indicate the existence of multiple metals or ligands in the active catalyst.

关键词： asymmetric catalysis C–H arylation ferrocene planar chirality pyridine

Application of neoadjuvant chemoradiotherapy and neoadjuvant chemotherapy in curative surgery for esophageal cancer:A metaanalysis

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 214-233页

作者： Mao-Xiu Yuan Qi-Gui cai Zhen-Yang Zhang jian-zhong Zhou cai-Yun Lan jiang-Bo Lin The Graduate School Fujian Medical UniversityFuzhou 350000Fujian ProvinceChina Department of Thoracic Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343000Jiangxi ProvinceChina Department of Thoracic Surgery Fujian Medical University Union HospitalFuzhou 350000Fujian ProvinceChina

BACKGROUND The effectiveness of neoadjuvant therapy in esophageal cancer(EC)treatment is still a subject of debate.AIM To compare the clinical efficacy and toxic side effects between neoadjuvant chemoradiotherapy(nCRT)and neoadjuvant chemotherapy(nCT)for locally advanced EC(LAEC).METHODS A comprehensive search was conducted using multiple databases,including PubMed,EMBASE,MEDLINE,Science Direct,The Cochrane Library,China National Knowledge Infrastructure,Wanfang Database,Chinese Science and Technology Journal Database,and Chinese Biomedical Literature Database Article.Studies up to December 2022 comparing nCRT and nCT in patients with EC were selected.RESULTS The analysis revealed significant differences between nCRT and nCT in terms of disease-free survival.The results indicated that nCRT provided better outcomes in terms of the 3-year overall survival rate(OSR)[odds ratio(OR)=0.95],complete response rate(OR=3.15),and R0 clearance rate(CR)(OR=2.25).However,nCT demonstrated a better 5-year OSR(OR=1.02)than nCRT.Moreover,when compared to nCRT,nCT showed reduced risks of cardiac complications(OR=1.15)and pulmonary complications(OR=1.30).CONCLUSION Overall,both nCRT and nCT were effective in terms of survival outcomes for LAEC.However,nCT exhibited better performance in terms of postoperative complications.

关键词： Esophageal cancer Neoadjuvant chemoradiotherapy Radical resection for esophageal cancer Neoadjuvant chemotherapy Meta-analysis

Tuning Surface Molecular Design of Porous Carbon for Blue Energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： jian Yu zhong-Lin Wang Tianwei Ma Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life cycle.However,because of limited performance,existing systems do not lend themselves to practical implementation.Although it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive mixing.Here,we show that manipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the electrodes.Our findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how manipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

Adjuvant therapy for hepatocellular carcinoma:Dilemmas at the start of a new era

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World Journal of Gastroenterology 2024年第8期30卷 806-810页

作者： jian-Hong zhong Department of Hepatobiliary Surgery Guangxi Medical University Cancer HospitalNanning 530021Guangxi Zhuang Autonomous RegionChina

Approximately 50%-70%of patients with hepatocellular carcinoma experience recurrence within five years after curative hepatic resection or ablation.As a result,many patients receive adjuvant therapy after curative resection or ablation in order to prolong recurrence-free survival.The therapy recommended by national guidelines can differ,and guidelines do not specify when to initiate adjuvant therapy or how long to continue it.These and other unanswered questions around adjuvant therapies make it difficult to optimize them and determine which may be more appropriate for a given type of patient.These questions need to be addressed by clinicians and researchers.

关键词： Adjuvant therapy Hepatocellular carcinoma Tumor recurrence Unanswered questions

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang jian-zhong Lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a century.Especially in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid mechanics.This paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle model.On this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be conducted.Finally,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction

BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： zhong-Mu Li cai-Yan Mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(GBP-GRP) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess constraint is more appropriate for clusters with small di

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

Westward Migration of Tropical Cyclone Activity in the Western North Pacific during 1982–2020:Features and Possible Causes

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Journal of Meteorological Research 2024年第1期38卷 1-9页

作者： jian zhong Huadong DU Yuqin WU Yuehua PENG China Satellite Maritime Tracking and Control Department Jiangyin 2144312 College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 4100733 Dalian Naval Academy Dalian 1160184 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

The westward migration of tropical cyclone(TC)activity has been identified in the western North Pacific(WNP),but the related features and causes remain elusive.Here,based on the best track data from China,Japan,and the US,and the NCEP–NCAR reanalysis data in 1982–2020,we investigate characteristics of the westward migration of the WNP TC activity with various metrics,and reveal possible causes for the migration of TC tracks through analyzing its seasonality and dependence on environmental conditions.The results show that the WNP TCs show significant westward migrations in a number of metrics,including location of tracks,genesis,the first track point at which TC reaches its lifetime-maximum intensity,and the last track point in the TC lifetime.It is found that TC tracks exhibit more significant westward migrations in the easterly steering flow than in the westerly steering flow.Meanwhile,the TC longitude shift shows notable seasonal variations,for which the TCs in the easterlies move further west than those in the westerlies during July–September,vice versa during October–December.The dependence of the westward migration of TC tracks on background steering flow is associated with the different environmental conditions.The westward shift in the westerly steering is mainly due to the reduced vertical wind shear(VWS),while the weakened zonal easterly steering and reduced VWS are both closely related to the westward migration in the easterly steering.These results have important implications for understanding current and future variations in TC longitude shift.

关键词： tropical cyclone westward migration steering flow vertical wind shear

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si zhong-Liang Li Wen-Hong Jia Lian Xue Hong-Xin Luo jian-cai Xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji Yu-Xin Leng Ren-zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Research on the MPPT of Photovoltaic Power Generation Based on Improved WOA and P&O under Partial Shading Conditions

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Energy Engineering 2024年第4期121卷 951-971页

作者： jian zhong Lei Zhang Ling Qin School of Electrical Engineering Nantong UniversityNantong226019China

Partial shading conditions(PSCs)caused by uneven illumination become one of the most common problems in photovoltaic(PV)systems,which can make the PV power-voltage(P-V)characteristics curve show multi-peaks.Traditional maximum power point tracking(MPPT)methods have shortcomings in tracking to the global maximum power point(GMPP),resulting in a dramatic decrease in output power.In order to solve the above problems,intelligent algorithms are used in MPPT.However,the existing intelligent algorithms have some disadvantages,such as slow convergence speed and large search oscillation.Therefore,an improved whale algorithm(IWOA)combined with the P&O(IWOA-P&O)is proposed for the MPPT of PV power generation in this paper.Firstly,IWOA is used to track the range interval of the GMPP,and then P&O is used to accurately find the MPP in that interval.Compared with other algorithms,simulation results show that this method has an average tracking efficiency of 99.79%and an average tracking time of 0.16 s when tracking GMPP.Finally,experimental verification is conducted,and the results show that the proposed algorithm has better MPPT performance compared to popular particle swarm optimization(PSO)and PSO-P&O algorithms.

关键词： Photovoltaic power generation maximum power point tracking whale algorithm perturbation and observation