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

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

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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

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Journal of Integrative Agriculture 2024年第1期23卷 122-140页

作者： Jingui Wei qiang Chai Wen Yin Hong Fan Yao guo Falong hu Zhilong Fan QimingWang State Key Laboratory of Aridland Crop Science Lanzhou 730070China College of Agronomy Gansu Agricultural UniversityLanzhou 730070China College of Life Sciences Northwest Normal UniversityLanzhou 730070China

The development of modern agriculture requires the reduction of water and chemical N fertilizer *** the planting density can maintain higher yields,but also consumes more of these restrictive ***,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains *** study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to *** treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N *** water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme *** with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improv

关键词： water and N reduction plant density maize grain yield N uptake compensation effect

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Preparation and Characterization of Molybdotungstoniobogermanic Acid

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Chinese Chemical Letters 1998年第5期9卷 505-508页

作者： Sheng Xian XU (Liaoyang Petrochemical Institute, Liaoyang 111003)guo qiang hu Qing Yin WU Yu Lin SONG (Deparatment of Chemistry, Liaoning University, Shenyang 110036) Liaoyang Petrochemical Institute Liaoyang 111003 China Deparatment of Chemistry Liaoning University Shenyang 110036 China

A new heteropoly complex has been prepared and characterized by chemical analysis, IR spectrum, UV spectrum, X-ray powder diffraction and thermal analysis.

关键词： heteropoly preparation characterization molybdotungstoniobogermanic acid

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In situ anchoring in carbon matrix of Bi_(2)O_(2)CO_(3) as a high-performance anode material for Li-ion batteries

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Rare Metals 2024年第8期43卷 3634-3646页

作者： Pu-qiang He Jun guo hui huang Zhong-Cheng guo Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Research Center of Metallurgical Electrode Materials Engineering Technology Kunming 650106China Kunming Hendera Science and Technology Co. Ltd.Kunming 650106China

Bismuth-based anode materials have been regarded as promising Li-ion batteries due to their high theoretical ***,their low conductivity and associated volume expansion inhabited their *** this work,Bi_(2)O_(2)CO_(3)@C composites were successfully synthesized by in situ anchoring of flower-like Bi_(2)O_(2)CO_(3) nanosheets on a carbon-based substrate via *** unique composited structure of Bi_2O_(2)-CO_(3)@C leads to a stable specific capacity of 547 mAh·g^(-1)after 100 cycles at a current density of 0.1 A·g^(-1).Notably,it demonstrates excellent rate capability with a specific capacity of 210 mAh·g^(-1)at 5 A·g^(-1).After 550 cycles at a current density of 0.5 A·g^(-1),a high reversible capacity of nearly 400 mAh·g^(-1)was ***,in situ X-ray diffraction measurements clearly demonstrate the conversion between Bi and Li_(3)Bi during alloying/dealloying,confirming the good electrochemical reversibility of the materials for Li *** reaction kinetics of Bi_(2)O_(2)CO_(3)@C were further investigated using galvanostatic intermittent titration ***,Bi_2O_(2)-CO_(3)@C exhibited excellent long-term stability,maintaining its high reversible capacity for over 200 cycles at a current density of 0.5 A·g^(-1)in a full cell configuration using Li_(1.20)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2) as the cathode *** result further underscores its promising potential for lithium-ion *** work may provide inspiration for the design of alloy-type negative electrode materials for high-performance rechargeable batteries.

关键词： Bi_(2)O_(2)CO_(3) Composite materials Anode materials Full batteries

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Salp Swarm Incorporated Adaptive Dwarf Mongoose Optimizer with Lévy Flight and Gbest-Guided Strategy

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Journal of Bionic Engineering 2024年第4期21卷 2110-2144页

作者： Gang hu Yuxuan guo Guanglei Sheng Department of Applied Mathematics Xi’an University of TechnologyXi’an710054People’s Republic of China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China Department of Electronics and Information Engineering Bozhou UniversityBozhou236800People’s Republic of China

In response to the shortcomings of Dwarf Mongoose Optimization(DMO)algorithm,such as insufficient exploitation capability and slow convergence speed,this paper proposes a multi-strategy enhanced DMO,referred to as ***,we propose an improved solution search equation that utilizes the Gbest-guided strategy with different parameters to achieve a trade-off between exploration and exploitation(EE).Secondly,the Lévy flight is introduced to increase the diversity of population distribution and avoid the algorithm getting stuck in a local *** addition,in order to address the problem of low convergence efficiency of DMO,this study uses the strong nonlinear convergence factor Sigmaid function as the moving step size parameter of the mongoose during collective activities,and combines the strategy of the salp swarm leader with the mongoose for cooperative optimization,which enhances the search efficiency of agents and accelerating the convergence of the algorithm to the global optimal solution(Gbest).Subsequently,the superiority of GLSDMO is verified on CEC2017 and CEC2019,and the optimization effect of GLSDMO is analyzed in *** results show that GLSDMO is significantly superior to the compared algorithms in solution quality,robustness and global convergence rate on most test ***,the optimization performance of GLSDMO is verified on three classic engineering examples and one truss topology optimization *** simulation results show that GLSDMO achieves optimal costs on these real-world engineering problems.

关键词： Dwarf mongoose optimization algorithm Gbest-guided Lévy flight Adaptive parameter Salp swarm algorithm Engineering optimization Truss topological optimization

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Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di Fan guo-qiang Zeng Hao-Wen Deng Lei Yan Jian Yang Chuan-Hao hu Song Qing Yang Hou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement ***,the complex and expensive hardware required does not facilitate the application or promotion of this ***,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and *** electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition *** relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature *** accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the *** learning is used to input the four shape parameters into the ***,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition *** partial-energy deposition events are removed to suppress Compton *** proposed method effectively decreases the MDA of an HPGeγ-energy dispersive *** results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

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Allosterically activating SHP2 by oleanolic acid inhibits STAT3-Th17 axis for ameliorating colitis

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2598-2612页

作者： Jinbo hu Wen Liu Yi Zou Chenyang Jiao Jiazhen Zhu qiang Xu Jianjun Zou Yang Sun Wenjie guo State Key Laboratory of Pharmaceutical Biotechnology Nanjing Drum Tower HospitalSchool of Life SciencesNanjing UniversityNanjing 210093China Department of Clinical Pharmacology Nanjing First HospitalNanjing Medical UniversityNanjing 210006China Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy Xuzhou Medical UniversityXuzhou 221004China

Src homology 2 domain-containing tyrosine phosphatase 2(SHP2)is an essential tyrosine phosphatase that is pivotal in regulating various cellular signaling pathways such as cell growth,differentiation,and *** activation of SHP2 has been shown to have a therapeutic effect in colitis and Parkinson's ***,the identification of SHP2 activators and a complete understanding of their mechanism is *** used a two-step screening assay to determine a novel allosteric activator of SHP2 that stabilizes it in an open *** acid was identified as a suitable *** binding to R362,K364,and K366 in the active center of the PTP domain,oleanolic acid maintained the active open state of SHP2,which facilitated the binding between SHP2 and its *** oleanolic acid-activated SHP2 hindered Th17 differentiation by disturbing the interaction between STAT3 and IL-6Rαand inhibiting the activation of ***,via the activation of SHP2 and subsequent attenuation of the STAT3-Th17 axis,oleanolic acid effectively mitigated colitis in *** protective effect was abrogated by SHP2 knockout or administration of the SHP2 inhibitor *** findings underscore the potential of oleanolic acid as a promising therapeutic agent for treating inflammatory bowel diseases.

关键词： Oleanolic acid SHP2 STAT3 Th17 Colitis Allosteric activator

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Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers

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Chinese Journal of Chemical Engineering 2024年第4期68卷 8-15页

作者： Pengxing Yuan Xiude hu Jingjing Ma Tuo guo Qingjie guo College of Chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass *** results reveal that the participation of OCs weakens the devolatilization intensity of *** the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic *** fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).

关键词： Oxygen carrier Co-pyrolysis Biomass Coal

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A Wideband High-Gain Sawtooth Slot Array Antenna with Frequency-Scanning at Lower Frequency and Fixed-Beam at Higher Frequency

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Chinese Journal of Electronics 2024年第2期33卷 463-471页

作者： qiang SUN Yongling BAN Jun hu School of Electronic Science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 *** 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Antenna measurements Slot antennas Surface waves Resonant frequency Gain measurement Conductors Frequency measurement

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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

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