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Recent Advances in Pd-Catalyzed Reactions Involving the “On-Water” Mechanism

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Chinese Journal of Chemistry 2024年第5期42卷 533-542页

作者： Dong Wei guo-qiang Lin State Key Laboratory of Systems Medicine for Cancer Shanghai Cancer InstituteShanghai Key Laboratory of Systems Regulation and Clinical Translation for CancerRen Ji HospitalShanghai Jiao Tong University School of MedicineShanghai200127 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China

As the chemical industry grapples with the need for more eco-friendly practices,the use of water as a reaction medium is gaining attraction in organic *** mini-review delves into Pd-catalyzed reactions that utilize the "on-water" mechanism,spanning from 2019 to late *** reactions are neatly categorized into several types: (A) Catalytic C—H activations,(B) Mizoroki- Heck-type reactions,(C) Suzuki-Miyaura reactions,and (D) Cyclization *** showcasing the potential of water as a sustainable reaction medium for organic transformations,these reactions leave no doubt about the importance of embracing eco-friendly practices in the chemical *** Scientists In 1980,a seminal work by Breslow et *** an acceleration of reaction rate in the Diels-Alder *** and co-workers noted a significant increase in the rate of the [2σ+2σ+2π] cycloaddition of quadricyclane and dimethyl azodicarboxylate (DMAD) when the reaction was conducted in water,as opposed to when it was carried out in organic *** term "on-water" was then coined to describe this *** strategy was further expanded to transition-metal catalyzed transformations by Ackermann in ***,Varma and Leazer disclosed a Pd-catalyzed Mizoroki-Heck type arylation of alkenes with diaryliodonium salts “on-water”.The enantioselective version of "on-water" process was not realized until 2014 by the Zhou *** on,the Schaub group described a Pd-catalyzed Suzuki–Miyaura coupling reaction of electron-poor aryl chlorides with water,using only 50 ppm of catalyst *** recently,Liu and Lin extended the "on-water" strategy to Pd-catalyzed double Mizoroki-Heck *** mini-review has focused on Pd-catalyzed reactions involving the “on-water” mechanism.

关键词： Pd-catalyzed “On-water” Green chemistry Aqueous reactions Mechanism Methodology and reactions Mizoroki-Heck reaction Cross-coupling

Design and implementation of a multi-tile parallel scanning rasterization accelerator

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 94-104页

作者： Xing Lidong guo qiang Peng Xinlong Feng Zhenfu School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

In the design of a graphic processing unit(GPU),the processing speed of triangle rasterization is an important factor that determines the performance of the *** architecture of a multi-tile parallel-scan rasterization accelerator was proposed in this *** accelerator uses a bounding box algorithm to improve scanning *** rasterizes multiple tiles in parallel and scans multiple lines at the same time within each *** highly parallel approach drastically improves the performance of *** the 65 nm process standard cell library of Semiconductor Manufacturing International Corporation(SMIC),the accelerator can be synthesized to a maximum clock frequency of 220 *** implementation on the Genesys2 field programmable gate array(FPGA)board fully verifies the functionality of the *** implementation shows a significant improvement in rendering speed and efficiency and proves its suitability for high-performance rasterization.

关键词： graphic processing unit(GPU) rasterization multi-tile parallelism

The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies

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Nuclear Science and Techniques 2024年第2期35卷 170-182页

作者： Gao-Yi Cheng Qian-Min Su Xi-Guang Cao guo-qiang Zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate *** urgently need solutions to the dilemma of traditional particle identification *** study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate *** intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 ***-based machine learning algorithms and deep learning algorithms *** show excellent performance and generalization *** additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is *** learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.

关键词： Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance

Experimental study on secondary air mixing along the bed height in a circulating fluidized bed with a multitracer-gas method

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Chinese Journal of Chemical Engineering 2024年第6期70卷 54-62页

作者： Qingyu Zhang Leming Cheng Kun Li Qixun Kang qiang guo Chaogang Wu Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China Dongfang Boiler Group Co.Ltd. Zigong 643001China

A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer *** were carried out on a cold CFB test rig with a cross-section of 0.42 m×0.73 m and a height of 5.50 *** effects of superficial velocity,SA ratio,bed inventory,and particle diameter on the SA mixing were *** results indicate that there are some differences in the measurement results obtained using different tracer gases,wherein the deviation between CO and CO_(2) ranges from 42%to 66%and that between O_(2) and CO_(2) ranges from 45%to 71%in the lower part of the fluidized ***,these differences became less pronounced as the bed height ***,the high solid concentration and fine particle diameter in the CFB may weaken the *** measurement results of different tracer gases show the same trends under the variation of operating *** superficial velocity and SA ratio and decreasing particle diameter result in better mixing of the *** effect of bed inventory on SA mixing is not monotonic.

关键词： Circulating fluidized bed Secondary air injection Gas mixing Multitracer-gas method

On the Intelligent Optimization of the Crevice Structure in a Rapid Compression Machine

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Journal of Thermal Science 2024年第3期33卷 1200-1215页

作者： guo qiang LIU Jie WU Yingtao WANG Hewu TANG Chenglong YU Ruiguang Department of Power Mechanical Engineering Beijing Jiaotong UniversityBeijing100044China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing100084China Beijing Key Laboratory of New Energy Vehicle Powertrain Technology Beijing100044China National International Science and Technology Cooperation Base Beijing Jiaotong UniversityBeijing100044China

In this study,the multi-objective intelligent optimization of the crevice structure in a rapid compression machine(RCM)is carried out based on the RCM simulation model modified with the KIVA-3V program.A multi-objective optimization simulation model of the crevice structure based on the large eddy simulation model coupled with the genetic algorithm NSGA-Ⅲis *** optimization parameters and seven optimization objectives are selected in the optimization *** results show that the genetic algorithm can quickly find the values of the optimized *** crevice volume ratio shows a trade-off relationship with the dimensionless temperature ratio T_(max)/T_(aver)and the tumble ratio.A larger crevice volume can reduce the flow of boundary layer cryogenic gas into the combustion chamber,thus improving the temperature *** addition,the crevice entrance width and the connecting channel length should be smaller,while the volume of the crevice main chamber should be larger,so as to sufficiently introduce the low-temperature gas of the boundary layer into the crevice and reduce their influence on the temperature field of the combustion *** the crevice volume accounts for10%of the total volume,the temperature uniformity of the combustor is significantly enhanced,and when the crevice volume accounts for 30.4%,there is almost no low-temperature vortex in the combustion chamber.

关键词： rapid compression machine adiabatic core area ignition delay period crevice structure

Colo-colonic intussusception as a rare complication of colonoscopy with polypectomy: Two case reports

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1939-1947页

作者： Sai-Heng Xiang guo-qiang Xu Department of Gastroenterology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Colonoscopy is the most frequently used diagnostic and therapeutic tool for the treatment of colorectal *** the complication rate is low,it can be potentially *** is a rare and severe complication often associated with *** a handful of post-colonoscopy intussusception cases have been reported,making this study a valuable addition to the medical *** SUMMARY Case 1:A 61-year-old man underwent colonoscopy with polypectomy for chronic abdominal *** patient experienced abdominal pain 11 hours later but was still discharged after pain *** was readmitted due to recurring *** tomography(CT)showed colo-colonic *** conservative management and attempts at endoscopic reduction failed;therefore,laparoscopic right hemicolectomy was *** examination revealed tubular adenomas in the polyps and inflammation in the resected *** 2:A 59-year-old woman underwent colonoscopy with polypectomy for a polyp in the transverse *** experienced upper abdominal pain,fever,nausea,and vomiting 9 hours after the *** CT and blood tests revealed a colo-colonic intussusception near the hepatic flexure and an elevated white blood cell *** attempts at endoscopic reduction failed and conservative treatment showed no *** underwent successful laparoscopic reduction and recovered *** examination of the resected polyp revealed *** Post-colonoscopy intussusception in adults is rare,and polypectomy may contribute to its *** diagnosis is crucial,with prompt CT examination serving as *** excluding malignancies,conservative management and reduction of intussusception should be considered before surgical bowel resection.

关键词： Intussusception Colonoscopy Polypectomy Complication Case report

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu Mao-Lin Xiong Liang-Quan Ge Qing-Xian Zhang guo-qiang Zeng Heng Lu Sheng-Liang guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Experimental Study of Local Scour Around Four Piles Under Different Attack Angles and Gap Ratios

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China Ocean Engineering 2024年第4期38卷 612-624页

作者： LIU Ming-ming TANG guo-qiang JIN Xin GENG Shao-yang School of Architecture and Engineering Liaocheng UniversityLiaocheng 252000China Water-Sediment Regulation and Sand Effective Utilization Special Laboratory of Shandong Provincial Education Department Liaocheng UniversityLiaocheng 252000China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China College of Energy Chengdu University of TechnologyChengdu 610059China

In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental *** research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical *** particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile *** these experimental trials,a wealth of local scour data were collected to support the *** data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test *** analysis of the experimental data provided interesting *** study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile *** of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the *** this initial rapid development,the scour depth transitioned to a more gradual change *** contrast,the scour topography around the piles continuously *** suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over *** results of this empirical investigation have significant implications for the design and constructio

关键词： local scour piles gap ratio attack angle

Lonicera Japonica Caulis Ameliorates LPS and TNF-α-Induced HT-29 Cell Injury by Inhibiting the MAPK/ERK/JNK/p38 Pathway

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Biomedical and Environmental Sciences 2024年第7期37卷 805-810页

作者： Hanxiu Lu Wei Yan Xiao Yuan Yongbo Kang Zhongjian Liu qiang guo Faculty of Life science and Technology Kunming University of Science and TechnologyKunming 650031YunnanChina School of medicine Kunming University of Science and TechnologyKunming 650031YunnanChina Department of Gastroenterology The First People’s Hospital of Yunnan ProvinceKunming 650032YunnanChina Department of Gastroenterology The First People’s Hospital of Yuxi CityYuxi 653100YunnanChina Institute of Basic and Clinical Medicine The First People’s Hospital of Yunnan ProvinceKunming 650032YunnanChina

Inflammatory bowel disease(IBD)is characterized by chronic inflammation of the intestinal tract,and shows a high rate of *** have accumulated extensive experience in the treatment of IBD,with biologics and small molecule drugs having greatly expanded the therapeutic scope of IBD in recent ***,such treatments involve a high price and a single target of drug action.

关键词： drugs treatment p38