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Highly efficient one-pot,three-component synthesis of1,5-benzodiazepine derivatives

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Chinese Chemical Letters 2014年第2期25卷 327-332页

作者： Xiao-Qing Li Lan-Zhi Wang The College of Chemistry and Material Science Hebei Normal University

为乙醇 4-methyl-2-(thiophen ) 的合成的一个一般、温和、有效的协议 -2,5-dihydro-1,5-benzodiazepine-3-carboxylate 在 0 点在乙醇用 H3PMo12O40 在第一次被完成 ?

关键词：邻苯二胺合成方法三组分二氮杂衍生物乙酰乙酸乙酯锅羧酸甲酯

Fluid Model Modulated by an M/M/1 Working Vacation Queue with Negative Customer

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Acta Mathematicae Applicatae Sinica 2018年第2期34卷 404-415页

作者： Xiu-li XU Xian-ying WANG xiao-feng SONG Xiao-Qing Li College of Science Yanshan University

This paper investigates a fluid model driven by an M/M/1 queue with working vacations and RCE （Removal of customer in the end） policy of negative customer. In the external environment, the negative customer is not served by the server and only removes the positive customer in the end one-to-one. We establish a fluid flow model based on this stochastic process, and obtain the mean buffer content and the probability of empty buffer for this fluid queue using the LT （Laplace transform） method. Moreover, several special cases of the model here are obtained. Finally, some numerical examples are presented to demonstrate the effects of parameters on the performance indices of the fluid model.

关键词： fluid model negative customer RCE （Removal of customer in the end） policy buffer content LT（Laplace transform）

Retrospection and Reflection on the Role of Henry C.Lu as a Traditional Chinese Medicine Writer,Educator,and Translator

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Chinese Medicine and Culture 2022年第3期5卷 148-153页

作者： xiao-li li li-An Ma qing Wu English Department School of HumanitiesBeijing University of Chinese MedicineBeijing 102488China

This paper respectfully commemorates the life of Dr.Henry C.Lu(1936-2022),who was the founding president of International College of Traditional Chinese Medicine of Vancouver.Dr.Lu was an active educator,a prolific writer and translator of traditional Chinese medicine(TCM)in the West and an influential figure during the initial stage of the international dissemination of TCM.By comprehensively searching,referencing,and cross-validating the literature,this article reviewed Dr.Lu’s major life events,bibliography,and,most importantly,his contribution to TCM education and translation.Dr.Lu should be given more credit for his achievements,and further studies are needed in future.

关键词： Education Henry C.Lu International dissemination Traditional Chinese medicine Translation Translator study

Rop plays conserved roles in the reproductive and digestive processes of spider mites

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Insect Science 2023年第2期30卷 351-364页

作者： Xue Xia Chang-Wu Peng qing-Tong Ye xiao-li Bing xiao-Yue Hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

Ras opposite(Rop)is known to play an essential role in regulating vesicle trafficking,including synaptic transmission and general secretion.The fundamental roles of Rop have been confirmed by the observation that null mutations in many organisms generate lethal phenotypes during embryogenesis.However,the effects of Rop during the postembryonic stages,especially in non-model organisms,remain largely unknown.Here,we provide new data that enhance our understanding of Rop's roles in the adults of multiple species of Tetranychus spider mites(Acari:Tetranychidae),a class of notorious agricultural pests.Our in silico and experimental evidence demonstrated that Rop is under purifying selection and is highly conserved in Tetranychus spp.RNA interference experiments showed that Rop is required for maintaining normal fecundity but has no significant effect on survival.We further demonstrate that knockdown of Rop darkens the body color of spider mites and blocks the excretion of fecal pellets,which is likely to be related to an abnormality in the excretion of food waste in the digestive system.Overall,our findings clarify novel functions of a vesicle trafficking-related gene in the adult stage of multiple Tetranychus species and highlight the need to evaluate the roles of essential genes in various organisms.

关键词： body color reproduction Rop spider mites Tetranychus vesicle trafficking

Experimental and theoretical study on the break phenomenon of self-pulsation for liquid-centered swirl coaxial injectors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第2期23卷 140-155页

作者： Peng-jin CAO xiao BAI qing-lian li Peng CHENG Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Experimental observations together with theoretical analysis were conducted to investigate the break phenomenon and the corresponding mechanisms of self-pulsation for a liquid-centered swirl coaxial injector with recess number of RN=1.Instantaneous spray images were obtained based on background light imaging technology with a high-speed camera.By dynamic analysis of the flow process of the liquid sheet in the recess chamber,a 1D self-pulsation theoretical model was established,and the self-sustaining mechanisms of self-pulsation were analyzed in depth.The results show that the increase of the momentum flux ratio will lead to the occurrence of the break phenomenon of self-pulsation for the injector with a larger recess length,and the frequency and intensity of self-pulsation before and after the break phenomenon differ significantly.The flow dynamics in the recess chamber sequentially transform from a periodic expansion-dominated flow to a stable flow,and then develop to a periodic contraction-dominated flow during the break process of self-pulsation.With the occurrence of self-pulsation before the break phenomenon,the liquid sheet has little effect on the pressure disturbance in the recess chamber.In contrast,with the occurrence of self-pulsation after the break phenomenon,the pressure disturbance is obviously affected by the liquid sheet.Based on the theoretical analysis model of self-pulsation,the self-pulsation frequency can be predicted.Furthermore,the self-sustaining mechanism of self-pulsation before and after the break phenomenon is preliminarily confirmed.The energy transfer between the gas-and liquid-phase is an important factor for maintaining the self-pulsation process.

关键词： Break phenomenon Theoretical model of self-pulsation Pressure oscillation characteristics Recess liquid-centered swirl coaxial(LCSC)injector

Tetracycline removal by a magnetic heterojunction Cu_(2)O/CoFe_(2)O_(4) activating peroxymonosulfate

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Rare Metals 2023年第3期42卷 862-874页

作者： Xiao-Qing Li Shan Feng Jun Yang Tai-Ping Xie Jian-Kang Wang xiao-Jing Chen De-Shun Kong Hou-Yang Chen Department of Chemical Engineering Chongqing Chemical Industry Vocational CollegeChongqing 401228China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Environmental Materials and Remediation Technologies College of Chemical and Environmental EngineeringChongqing University of Arts and SciencesYongchuan 402160China School of Materials Science and Engineering Yangtze Normal UniversityChongqing 408100China School of Mining and Civil Engineering Liupanshui Normal UniversityLiupanshui 553004China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The electron transfer mechanism in the process of peroxymonosulfate(PMS)activation using heterojunction catalyst was controversial.In this work,magnetic heterojunction Cu_(2)O/CoFe_(2)O_(4)(CC)was first synthesized to activate PMS.An innovative reaction mechanism based on built-in electric field-driven electron migration from Cu2O to CoFe2O4 and effective magnetic moment of CC for enhancing PMS activation was proposed.Meanwhile,the CC/PMS system was used for efficient removal of antibiotic tetracycline(TC).Under optimal conditions,98.0%TC could be removed using CC/PMS catalytic system after only 30 min.The catalytic activity was higher than that of Cu_(2)O/PMS and CoFe_(2)O_(4)/PMS.Meanwhile,the impact of solution pH on TC removal was insignificant,suggesting the pH-insensitive PMS activation ability of CC.Besides,the coexisting inorganic ions in the environment,such as HCO_(3)-,H_(2)PO4-,NO_(3)-,Cl-and humic acid(HA)as representative of natural organic matter,did not inhibit TC removal in CC/PMS system.Furthermore,CC/PMS system exhibited excellent reusability with more than94.0%TC removal after the 5th reuse.Electron paramagnetic resonance(EPR)tests and quenching experiments showed that O_(2)·-and 1O_(2) played vital roles in TC removal.The intermediate products and corresponding toxicity assessment revealed that this catalytic system could reduce TC toxicity.This work provided new insights into the PMS activation mechanism using heterogeneous magnetic catalysts,including transition metal oxide.

关键词： Peroxymonosulfate(PMS)activation Heterojunction catalyst Electron migration Cu2O CoFe204

Investigation on the stall types in impellers with different blade numbers

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Journal of Hydrodynamics 2023年第2期35卷 299-313页

作者： xiao-dong liu Yao-jun li Zhu-qing liu Wei Yang College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

Stall is a complex flow phenomenon and its existence usually shows significant differences in different impeller forms.In this paper,the flow field characteristics and mechanism of stall types in impellers with different blade numbers were studied through the combination of experiment and numerical simulation at stall inception stage.In the experiments,it was observed that the five-blade impeller entered the rotating stall stage from a relatively stable flow field within a small flow rate interval.For the six-blade impeller,the root cause that stall vortices appeared in channels alternately rather than each one evenly was also reasonably explained.The validated numerical simulation method was utilized to reveal the three-dimensional flow field in impeller channels.The results indicate the swirling vortex near the impeller shroud was periodically sucked in and escaped from region near the blade suction side,which was the fundamental driving force of rotating stall.The sudden change of flow field caused by the fusion of the separation vortex at the channel inlet and the vortex induced by the swirling vortex near shroud is the essential reason for the formation of alternating stall.What’s more,the stall inception flow field is clearly defined in impellers,which is of great significance for the further analysis of stall characteristics.Based on the distribution characteristics of vortex structure near impeller shroud with different blade numbers at different flow rate conditions,this paper deeply investigated the formation mechanism of different stall types in impellers.

关键词： Numerical simulation high-frequency particle image velocimetry(PIV) impellers swirling vortex stall type

Ionic Radius Dependent Kinetic Behavior for the Self-Assemblyand Chiral Amplification of Lanthanide Tetrahedral Cages

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Chinese Journal of Chemistry 2023年第7期41卷 797-804页

作者： Shao-Jun Hu xiao-qing Guo li-Peng Zhou li-Xuan Cai Chong-Bin Tian qing-Fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary Understanding the kinetic process during the self-assembly and chiral amplification of metal-organic polyhedra(MOPs)is critical for the rational preparation of chiral MOPs.Herein,we report the ionic radius dependent kinetic processes for the self-assembly and chiral amplification of Ln4L4-type(Ln,Lanthanides;L,ligand)lanthanide tetrahedral cages.The chiral Eu4(LR)4 tetrahedral cage is structurally characterized by nuclear magnetic resonance(NMR),electrospray ionization time-of-flight mass spectrometry(ESI-TOF-MS),and single crystal X-ray diffraction.Kinetic study on the stereo-controlled self-assembly of circularly polarized luminescence(CPL)-active Ln4(LR)4(Ln=LaIII,PrIII and EuIII)tetrahedra manifests that the larger ionic radius of Ln leads to faster assembly rates.Mixed-ligand cage assembly experiments with chiral LR/S,achiral Lac and Ln(1:3:4 molar ratio)reveal that the self-assembly and chiral amplification occur synchronously for the LaIII and PrIII cages,while two distinct steps,i.e.,first self-assembly and then chiral amplification,are observed for the EuIII cage.Such distinct kinetic behavior is attributed to different ligands exchange rates among the mixed-ligand Ln4L4 cages.This work provides fundamental guidance for fabrication and property-optimization of chiral lanthanide-based molecular materials.

关键词： Chiral lanthanide tetrahedron Self-assembly Chiral amplification Kinetic lonic radius

Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital

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World Journal of Gastroenterology 2024年第19期30卷 2523-2537页

作者： Mu-Han li Ge-Chong Ruan Wei-Xun Zhou Xiao-Qing Li Sheng-Yu Zhang Yang Chen xiao-Yin Bai Hong Yang Yu-Jie Zhang Peng-Yu Zhao Ji li Jing-Nan li Department of Gastroenterology Chinese Academy of Medical Sciences&Peking Union Medical College HospitalBeijing 100730China Department of Pathology Chinese Academy of Medical Scinences&Peking Union Medical College HospitalBeijing 100730China Department of Pathology Tianjin First Central HospitalNankai UniversityTianjin 300192China Affairs Office Chinese Academy of Medical Sciences&Peking Union Medical College Hospital(West campus)Beijing 100032China

BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressan

关键词： Autoimmune enteropathy Clinical manifestations Diagnostic criteria Pathological features Long-term prognosis