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Selective control of secondary alcohols upgrading using Ir-catalyzed cross-coupling strategy

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Science China Chemistry 2024年第3期67卷 914-921页

作者： Siqi Yang Zeye lu Jiale Ji Qingshu Zheng Tao tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The selective coupling of alcohols is a fascinating yet challenging approach for upgrading alcohols. Herein, we accomplished the controlled production of β-disubstituted ketones or upgraded secondary alcohols via the Ir-catalyzed cross-coupling of secondary alcohols in excellent yields with broad substrate scopes. This selective control was achieved by using an in-situ generated monoNHC-Ir or a tris-NHC-Ir complex as the catalysts, respectively. Mechanistic studies revealed that the delicate balance between dehydrogenation and hydrogenation abilities of these bifunctional catalysts is crucial for achieving different selectivity. The tris-NHC-Ir complex effectively facilitated dehydrogenation of alcohols and hydrogenation of intermediates, leading to the desired upgraded secondary alcohols. Conversely, the high dehydrogenation ability of the mono-NHC-Ir complex promoted the conversion of formed secondary alcohols back to ketones.

关键词： cross-coupling hydrogen-borrowing NHC-Ir complexes selectivity control upgrading of alcohols

Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2263-2273页

作者： Dongfei lu Guoqiang Xi Hangren Li Jie tu Xiuqiao Liu Xudong Liu Jianjun Tian Linxing Zhang Institute for Advanced Materials Technology University of Science and Technology BeijingBeijing 100083China

BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant ***,BFO suffers from a large leakage current,resulting in poor ferroelectric ***,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were *** confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based *** and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward *** force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared *** ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mn

关键词： increasing entropy synergistic ferroelectric film remnant polarization leakage current

Anti-psoriasis molecular targets and active components discovery of Optimized Yinxieling Formula via affinity-purified strategy

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Chinese Journal of Natural Medicines 2024年第2期22卷 127-136页

作者： WANG Wei LIU Lijuan YANG Zhuo lu Chuanjian tu Pengfei ZHAO Ruizhi ZENG Kewu State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510006China

Psoriasis,a prevalent inherited skin condition,involves an inflammatory response as a key pathogenic *** Optimized Yinxieling Formula(OYF),rooted in traditional Chinese medicine,is extensively utilized in clinical settings to treat *** previous studies have demonstrated OYF’s significant anti-inflammatory effects in psoriasis,its potential molecular targets and active components remain *** study aimed to unveil the anti-psoriasis molecular targets and active components of *** findings indicated that OYF extract markedly reduced the production of several inflammatory mediators,including IL-23,nitric oxide,TNF-α,and IL-1β,in LPS-induced RAW264.7 *** synthesized OYF extract-crosslinked beads to isolate pharmacological targets from RAW264.7 lysates using an affinity purification strategy,known as Target *** enriched target proteins were subsequently identified via LC-MS/MS,followed by bioinformatics analysis to map the psoriasis-associated pathway-gene *** identified a total of 76 potential target proteins,which were highly associated with mRNA transcription *** particular,pathway-gene network analysis revealed that the IL-23 inflammatory pathway was involved in the anti-psoriasis effect of OYF *** further utilized a target protein-based affinity capture strategy,combined with LC-MS and SPR analysis,to globally screen OYF’s active components,focusing on the mRNA transcription regulator,fused in sarcoma(FUS).This process led to the identification of umbelliferone,vanillic acid,protocatechuic acid,gentisic acid,and echinacoside as key compounds targeting FUS to inhibit IL-23 ***,we formulated a compound cocktail(CpdC),which significantly reduced psoriasis area and severity index(PASI)scores and the expressions of IL-23 and Ki67 in an imiquimod(IMQ)-induced psoriasis mouse ***,our study elucidates the primary molecular targets and active components of OYF,offeri

关键词： Psoriasis Optimized Yinxieling Formula(OYF) FUS protein Molecular targets Affinity-purified strategy

Effects of oral probiotics on inflammation and intestinal function in adult patients after appendectomy:Randomized controlled trial

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1371-1376页

作者： Ke Lan Ke-Rui Zeng Fu-Rui Zhong Sheng-Jin tu Jin-Long luo Shi-Long Shu Xue-Feng Peng Hua Yang kai lu Department of General Surgery Zigong Fourth People's HospitalZigong 643000Sichuan ProvinceChina

BACKGROUND Appendectomy is an acute abdominal surgery that is often accompanied by severe abdominal *** probiotics are one of the postoperative treatments for rapid ***,there is a lack of prospective studies on this topic after *** To investigate whether the postoperative probiotics can modulate the inflammatory response and restore intestinal function in patients following *** This was a prospective,randomized trial.A total of 60 emergency patients were randomly divided into a control group(n=30)and a probiotic group(n=30).Patients in the control group started to drink some water the first day after surgery,and those in the probiotic group were given water supplemented with Bacillus licheniformis capsules for 5 consecutive days *** indices of inflammation and postoperative conditions were recorded,and the data were analyzed with RStudio 4.3.2 *** A total of 60 participants were *** with those in the control group,the C-reactive protein(CRP),interleukin 6 and procalcitonin(PCT)levels were significantly lower in the probiotic group at 2 d after surgery(P=2.224e-05,P=0.037,and P=0.002,respectively,all PluSION Postoperative oral administration of probiotics may modulate the gut microbiota,benefit the recovery of the early inflammatory response,and subsequently enhance recovery after appendectomy.

关键词： Probiotics Gut microbiota Appendectomy Inflammatory markers Intestinal function Enhanced recovery after surgery Postsurgical infections

Phase-Dislocation-Mediated High-Dimensional Fractional Acoustic-Vortex Communication

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Research 2024年第3期2023卷 575-584页

作者： Ruijie Cao Gepu Guo Wei Yue Yang Huang Xinpeng Li Chengzhi kai Yuzhi Li Juan tu Dong Zhang Peng Xi Qingyu Ma School of Computer and Electronic Information Nanjing Normal UniversityNanjing 210023China Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China nstitute of Acoustics Nanjing UniversityNanjng 210093China National Biomedical Imaging Center Peking UniversityBeijing 100871China

With unlimited topological modes in mathematics,the fractional orbital angular momentum(FOAM)demonstrates the potential to infinitely increase the channel capacity in acoustic-vortex(AV)***,the accuracy and stability of FOAM recognition are still limited by the nonorthogonality and poor anti-interference of fractional AV *** popular machine learning,widely used in optics based on large datasets of images,does not work in acoustics because of the huge engineering of the 2-dimensional point-by-point ***,we report a strategy of phase-dislocation-mediated high-dimensional fractional AV communication based on pair-FOAM multiplexing,circular sparse sampling,and machine *** unique phase dislocation corresponding to the topological charge provides important physical guidance to recognize FOAMs and reduce sampling points from theory to practice.A straightforward convolutional neural network considering turbulence and misalignment is further constructed to achieve the stable and accurate communication without involving experimental *** experimentally present that the 32-point dual-ring sampling can realize the 10-bit information transmission in a limited topological charge scope from±0.6 to±2.4 with the FOAM resolution of 0.2,which greatly reduce the divergence in AV *** infinitely expanded channel capacity is further verified by the improved FOAM resolution of *** with other milestone works,our strategy reaches 3-fold OAM utilization,4-fold information level,and 5-fold OAM *** of the extra advantages of high dimension,high speed,and low divergence,this technology may shed light on the next-generation AV communication.

关键词： infinitely topological fractional

碳柱观测合作网络(COCCON)甲烷监测进展及其在中国的初步应用

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遥感学报 2024年第8期28卷 1955-1967页

作者：涂倩思秦凯鹿凡同济大学机械与能源工程学院上海201804 卡尔斯鲁厄理工学院气象与气候研究院德国卡尔斯鲁厄76344 中国矿业大学环境与测绘学院徐州221116

地基遥感技术是监测大气温室气体柱浓度、校准卫星和研究碳源汇的有效手段。基于便携式傅里叶光谱仪EM27/SUN的碳柱观测合作网络(COCCON)可以作为全球碳柱总量观测网(TCCON)的有效补充。本文介绍了COCCON仪器线型函数ILS与开放路径测量... 详细信息

地基遥感技术是监测大气温室气体柱浓度、校准卫星和研究碳源汇的有效手段。基于便携式傅里叶光谱仪EM27/SUN的碳柱观测合作网络(COCCON)可以作为全球碳柱总量观测网(TCCON)的有效补充。本文介绍了COCCON仪器线型函数ILS与开放路径测量方法、高精度反演算法PROFFAST,展现了仪器的高稳定性和反演结果的较低的不确定性,梳理总结了COCCON甲烷观测在卫星遥感反演验证、城市排放、煤矿区排放、畜牧业排放等方面的研究进展,呈现了COCCON仪器在中国城市及煤矿区甲烷监测中的初步应用并展望了下一步需要研究的重点问题。

关键词：温室气体地基遥感傅里叶变换光谱仪 EM27/SUN 碳柱观测合作网络甲烷煤矿区排放

An Assembly of Pyrano[3,2-b]indol-2-ones via NHC-Catalyzed[3+3]Annulation of Indolin-3-ones with Ynals

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Chinese Journal of Chemistry 2024年第13期42卷 1487-1492页

作者： Xia Wang Shulei Zhang Shao-Jie Wang Hao An Xiaolan Xin Haonan Lin Zhifeng tu Shenci lu Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Instituteof Biomedical Materials and Engineering(SiBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China School of Chemistry and Chemical Engineering Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

We report herein an unprecedented N-heterocyclic carbene-catalyzed formal[3+3]annulation of ynals with N-Ts indolin-3-ones under the oxidation condition affording the functionalized pyrano[3,2-b]*** alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this *** method features a broad substrate scope and mild conditions,including axially chiral skeletons with suitable substitutions.

关键词： N-Heterocyclic carbene Annulation Organocatalysis Atropisomerism Carbazole Aldehydes Heterocycles Asymmetric catalysis

Structural and luminescent Properties of Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)Green-Emitting Transparent Ceramic Phosphor

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 533-540页

作者：郝留成 MIAO Xiaojun LI kai ZHONG Jianying 涂兵田 YANG Zhangfu 王皓 Pinggao Group Co. LtdPingdingshan 467001China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 430070China School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001China

A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction *** transparent ceramic phosphors were fabricated by pressureless sintering followed by hot-isostatic pressing(HIP).The crystal structure,luminescence and mechanical properties of the samples were systematically *** transparent ceramic phosphors with tetrahedrally coordinated Mn^(2+)show strong green emission centered around 515 nm under blue light *** the Mn^(2+)concentration increases,the crystal lattice expands slightly,resulting in a variation of crystal field and a slight red-shift of green emission *** weak absorption peaks in the transmittance spectra originate from the spin-forbidden ^(4)T_(1)(^(4)G)→^(6)A_(1) transition of Mn^(2+).The decay time was found to decrease from 5.66 to 5.16 ms with the Mn^(2+)*** present study contributes to the systematic understanding of crystal structure and properties of MgAlON:xMn^(2+)green-emitting transparent ceramic phosphor which has a potential application in high-power light-emitting diodes.

关键词： transparent ceramic phosphor green emission MgAlON photoluminescence

Random vibration analysis of FGM plates subjected to moving load using a refined stochastic finite element method

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Defence Technology（防务技术） 2024年第4期34卷 42-56页

作者： Ngoc-tu Do Trung Thanh Tran Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte Carlo simulation(MCS), so-called refined stochastic finite element method to investigate the random vibration of functionally graded material(FGM) plates subjected to the moving *** advantage of the proposed method is to use r-FSDT to improve the accuracy of classical FSDT, satisfy the stress-free condition at the plate boundaries, and combine with MCS to analyze the vibration of the FGM plate when the parameter inputs are random quantities following a normal distribution. The obtained results show that the distribution characteristics of the vibration response of the FGM plate depend on the standard deviation of the input parameters and the velocity of the moving ***, the numerical results in this study are expected to contribute to improving the understanding of FGM plates subjected to moving loads with uncertain input parameters.

关键词： FGM Moving load R-FSDT Q4 element Monte Carlo simulation Random vibration