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Sigmatropic rearrangements of B(MIDA)-propargylic alcohols towards the diverse synthesis of α-functionalized organoborons

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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian li-Cai liu Zhi-Hao Chen Yuan liu yin li Qingjiang li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organoborons are useful building blocks and key structural elements in functional *** previous synthesis relied on the famous Matteson reaction or the late-stage borylative modification of alkynes or ***,the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively *** report herein that B(MIDA)-propargylic alcohols(BPAs) are a useful type of borylated building *** two complementary functional group handles(alkyne and hydroxyl) in close proximity,the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates,including α,β-unsaturated acylborons,α-S/P-substituted allenylborons,boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine,some of which are otherwise challenging targets using other synthetic methods.

关键词： organoboron diverse synthesis sigmatropic rearrangement heteroarene amide

Cocrystals of carbamazepine:Structure,mechanical properties,fluorescence properties,solubility,and dissolution rate

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Particuology 2024年第7期90卷 20-30页

作者： Jinbo Ouyang lishan liu yin li Mingyang Chen limin Zhou Zhirong liu li Xu Hamza Shehzad School of Chemistry and Materials Science East China University of TechnologyNanchang 330013China School of Physics and Materials Science Nanchang UniversityNanchang 330013China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

Carbamazepine(CBZ)is an anticonvulsant with very low water solubility,presenting as a white crystalline powder with poor mechanical properties and is hard to *** enhance CBZ's physicochemical properties,such as water solubility and mechanical properties,we selected six cocrystal coformers(CCFs):nicotinamide(NIC),benzamide(BZM),salicylic acid(SCA),fumaric acid(FMA),trimesic acid(TMA),and hesperetin(HPE).Six CBZ cocrystals were successfully prepared using the solution *** transform infrared spectroscopy(FT-IR),powder X-ray diffraction(PXRD),differential scanning calorimetry(DSC),and single crystal X-ray diffraction(SCXRD)were used to characterize the crystal structures and gain comprehensive insights into the six *** mechanical,fluorescence,and solubility properties of the six cocrystals were *** results reveal that most of the prepared cocrystals exhibit improved water solubility and mechanical properties when compared to *** them,the dissolution rate of cocrystals excluded from CBZ-HPE has increased by an average of 3 or 4 times compared to CBZ,while CBZ-HPE exhibits superior mechanical ***,all six cocrystals possess better fluorescence performance than *** thoroughly evaluated the mechanical properties of the cocrystals through both experimental and theoretical *** work provides a new direction for studying drug cocrystals to improve the physicochemical properties of drugs.

关键词： Carbamazepine Cocrystal Mechanical properties Fluorescence performance Dissolution rate

Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： yin-Ping li Xin-Bo Ge Xi-lin Shi Hong-ling Ma State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Energy and Mining Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In China, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao Gao Bing-rong Zhang yin-ming li Zhi-ming Wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

Cross-linked Electrospun Gel Polymer Electrolytes for lithium-Ion Batteries

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Chinese Journal of Polymer Science 2024年第8期42卷 1021-1028页

作者： Xue Gong Qin Xiao Qing-yin li Wen-Cui liang Feng Chen Long-Yu li Shi-Jie Ren College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

lithium-ion batteries(liBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage ***,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical *** obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled li/liFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 *** results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes lithium-ion batteries

Ginsenoside Rd Induces Differentiation of Myeloid Leukemia Cells via Regulating ERK/GSK-3βSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第7期30卷 588-599页

作者： JIANG Yu-xia ZHAO Yan-na YU Xiao-ling yin li-ming Department of Hematology Tongde Hospital of Zhejiang ProvinceHangzhou310012China Institute of Hematology Research the First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou310006China

Objective To investigate the role of ginsenoside Rd(GRd)in acute myeloid leukemia(AML)cell *** AML cells were treated with GRd(25,50,100 and 200µg/mL),retinoic acid(RA,0.1g/L)and PD98059(20 mg/mL)for 72 h,cell survival was detected by methylthiazolyldiphenyl-tetrazolium bromide and colony formation assays,and cell cycle was detected by flow *** morphology and differentiation were observed by Wright-Giemsa staining,peroxidase chemical staining and cellular immunochemistry assay,*** protein expression levels of GATA binding protein 1(GATA-1),purine rich Box-1(PU.1),phosphorylated-extracellular signal-related kinase(p-ERK),ERK,phosphorylated-glycogen synthase kinase-3β(p-GSK3β),GSK3βand signal transducer and activator of transcription 1(STAT1)were detected by Western ***-six mice were randomly divided into 3 groups using a random number table:model control group(non-treated),GRd group[treated with 200 mg/(kg·d)GRd]and homoharringtonine(HTT)group[treated with 1 mg/(kg·d)HTT].A tumor-bearing nude mouse model was established,and tumor weight and volume were *** of subcutaneous tumor tissue were observed after hematoxylin and eosin ***1 and GATA-1 expressions were detected by immunohistochemical *** The cell survival was inhibited by GRd in a dose-dependent manner and GRd caused G0/G1 cell arrest(plicited upregulation of p-ERK,p-GSK-3βand STAT1 expressions in cells,and reversed the effects of PD98059 on inhibiting the expressions of peroxidase,GATA-1 and PU.1(P<0.05).After GRd treatment,tumor weight and volume of mice were decreased,and tumor cells underwent massive apoptosis and necrosis(P<0.05).WT1 level was decreased,and GATA-1 level was significantly increased in subcutaneous tumor ti

关键词： ginsenoside Rd myeloid leukemia survival differentiation extracellular signal-related kinase signaling pathway

A MOF/poly(thioctic acid)composite for enhanced gold extraction from water matrices

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Nano Research 2024年第1期17卷 382-389页

作者： Ruiqing li Sen Yan Tianwei Xue Rongxing Qiu yin li Wenli Hao Guangkuo Xu Yanliang Wang Yanzhen Hong Yuzhong Su Hongtao Wang Shuliang Yang li Peng Jun li College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China College of Energy Xiamen UniversityXiamen 361005China National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and EstersXiamen UniversityXiamen 361005China Collaborative Innovation Center of Chemistry for Energy Materials Xiamen UniversityXiamen 361005China

With the fast generation of electronic waste(e-waste)and the increasing depletion of metal resources,“urban mining”that can selectively recover gold from secondary resources has attracted great *** of materials with high extraction capacity and satisfying selectivity in complex aqueous-based matrices still remains ***,a novel metal-organic framework/polymer composite(Fe-BTC/poly(thioctic acid),denoted as Fe-BTC/pTA)has been newly synthesized and applied for selective gold recovery in different matrices(river water,seawater,and leaching solution of e-waste).Benefiting from the high specific surface area and suitable pore sizes as well as the rational design of active sites,the composite exhibits high adsorption capacity(920 mg/g),high removal efficiency(>99%),fast kinetics(below 0.1 ppb within 10 min),and good applicability in complex matrices,which are better than those of most reported sulfur-containing ***-state metallic gold with high purity can be effectively enriched due to the high recyclability and long-term stability of the *** material after adsorption can be further applied as a heterogeneous catalyst for water remediation due to the in situ generated gold nanoparticles by the redox reaction between Au(III)ions and the S-containing groups in the composites.

关键词： metal-organic frameworks(MOFs) poly(thioctic acid)(pTA) polymer composites gold recovery urban mining

Numerical Simulation of Oil-Water Two-Phase Flow in Low Permeability Tight Reservoirs Based on Weighted Least Squares Meshless Method

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1539-1552页

作者： Xin liu Kai Yan Bo Fang Xiaoyu Sun Daqiang Feng li yin School of GeoSciences Yangtze UniversityWuhan430100China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Southwest Petroleum University) Chengdu610000China Downhole Service Company Petro China Qinghai Oilfield CompanyHaixi817000China Research Institute of Drilling and Production Technology Petro China Qinghai Oilfield CompanyDunhuang736200China PetroChina Qinghai Oilfield Company The Third Oil Plant Dunhuang736200China

In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary *** radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence *** shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal ***,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved *** results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and ***,the impact of fracture half-length on the productivity of horizontal wells is *** results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production.

关键词： Weighted least squares method meshless method numerical simulation of low permeability tight reservoirs oil-water two-phase flow fracture half-length

Metal-N_(4)model single‐atom catalyst with electroneutral quadri‐pyridine macrocyclic ligand for CO_(2)electroreduction

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Carbon Energy 2024年第8期6卷 122-133页

作者： Jian‐Zhao Peng yin‐Long li Yao‐Ti Cheng Fu‐Zhi li Bo Cao Qing Wang Xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst