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Reduction of unactivated alkyl chlorides enabled by light-induced single electron transfer

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Science China Chemistry 2024年第2期67卷 471-481页

作者： Lei Dai Zhao-Fei Zhang xiang-Yu Chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing100049China Institute of Chemistry Chinese Academy of SciencesBeijing100190China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou256606China

Alkyl chlorides are abundant and easily accessible starting ***,due to the high reduction potentials associated with unactivated alkyl chlorides,achieving their single electron reduction remains a persistent *** challenge has spurred the exploration of efficient activation methods to overcome this *** recent years,photocatalysis has emerged as a mild and potent tool for the single electron reduction of unactivated alkyl chlorides,opening up new possibilities in this *** the rapid advancements in this area,a comprehensive review that provides a conceptual understanding of this emerging field,with a specific focus on reaction design and catalytic mechanisms,would be timely and highly ***,we present an overview of various synthetic techniques for photoinduced single electron reduction of unactivated alkyl ***,we also discuss the limitations of the present methods and future directions that lie ahead in this field.

关键词： photocatalysis unactivated alkyl chlorides single electron transfer radical reactions

Biomimetic Gland Models with Engineered Stratagems

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Research 2024年第2期2023卷 583-612页

作者： xiang Lin Lingyu Sun Minhui Lu Yuanjin Zhao Department of Rheumatology and Immunology Nanjng Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325001China Southeast University Shenzhen Research Institute Shenzhen 518071China

As extensively distributed tissues throughout the human body,glands play a critical role in various physiological ***,the construction of biomimetic gland models in vitro has aroused great interest in multiple *** the biological field,the researchers focus on optimizing the cell sources and culture techniques to reconstruct the specific structures and functions of glands,such as the emergence of organoid *** the perspective of biomedical engineering,the generation of biomimetic gland models depends on the combination of engineered scaffolds and microfluidics,to mimic the in vivo environment of glandular *** engineered stratagems endowed gland models with more biomimetic features,as well as a wide range of application *** this review,we first describe the biomimetic strategies for constructing different in vitro gland models,focusing on the role of microfluidics in promoting the structure and function development of biomimetic *** summarizing several common in vitro models of endocrine and exocrine glands,the applications of gland models in disease modelling,drug screening,regenerative medicine,and personalized medicine are ***,we conclude the current challenges and our perspective of these biomimetic gland models.

关键词： endowed constructing strata

Optimizing hemicelluloses pre-extraction in eucalyptus kraft pulping:A pathway towards enhancing pulp mill biorefineries

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Chinese Journal of Chemical Engineering 2024年第6期70卷 162-172页

作者： Yuhan Wang Danqi Xue Jingjing Zhuo Zhouyang xiang State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

A critical pathway towards enhancing pulp mill biorefineries is to integrate the extraction and utilization of hemicelluloses into the pulping ***,an industrial pre-extraction strategy for hemicelluloses targeting eucalyptus kraft pulping process was *** solution or pulping white liquor was used to pre-extract hemicelluloses before the actual pulping *** response surface methodology(RSM)technique was applied to investigate the most suitable conditions to maximize the yield of these hemicelluloses while simultaneously minimizing the damage to pulp yields and ***(105 to 155℃),alkali concentration(3%to 8%),sulfidity(20%to 30%)and retention time(19 to 221 min)were combined to evaluate their effects on hemicellulose yields and chemical *** optimal pre-extraction conditions identified in this work(5.75%NaOH concentration,25%sulfidity at 135℃for 60 min)successfully allowed recovering 4.8%of hemicelluloses(based on the wood dry mass)and limited damages to pulp yields and *** cellulose content in pulp can even be increased by about 10%.Hemicellulose emulsification properties were also evaluated,which were comparable to synthetic *** study provides an industrial pathway to effectively separate and utilize wood hemicelluloses from the pulping process,which has the potential to improve the economy and material utilization of pulp and paper mills.

关键词： Hemicelluloses Xylan Pre-extraction Kraft pulping Emulsifying Response surface methodology(RSM)

Superhydrophobic magnetic Fe_(3)O_(4) polyurethane sponges for oil-water separation and oil-spill recovery

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Journal of Environmental Sciences 2024年第5期139卷 160-169页

作者： Shiyu Wu Yunjie xiang Yaqi Cai Jingfu Liu Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310024China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

The effective and affordable separation of oil and water,a crucial process in the safe han dling of environmental disasters such as crude oil spills and recovery of valuable resources is a highly sought-after yet challenging ***,superhydrophobic PU sponge was fab ricated for the fast and cost-effective adsorptive separation of oil and different organic sol vents from ***(OTS)-functionalized Fe_(3)O_(4)@SiO_(2)core-shell mi crospheres were dip-coated on the surface of porous materials via a dip-coating process thereby endowing them with *** to the hydrophobic interaction between OTS molecules and oil and increased capillary force in the micropores,the result ing superhydrophobic sponge served as a selective oil-sorbent scaffold for absorbing oil from oil-water mixtures,including oil-water suspensions and ***,after the recovery of the adsorbed oil via mechanical extrusion,these superhydrophobic materials could be reused multiple times and maintain their oil-water separation efficacy even afte 10 oil-water separation cycles.

关键词： Fe_(3)O_(4)@SiO_(2)-OTS polyurethane sponge Oil-water separation Adsorption capacity Oil-spill recovery

Bioinspired nanotransducers for neuromodulation

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Nano Research 2024年第2期17卷 618-632页

作者： Fan Yang xiang Wu Sa Cai Guosong Hong Department of Materials Science and Engineering Stanford UniversityStanfordCA 94305USA Wu Tsai Neurosciences Institute Stanford UniversityStanfordCA 94305USA School of Science Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China

The field of neuromodulation has experienced significant advancements in the past decade,owing to breakthroughs in disciplines such as materials science,genetics,bioengineering,photonics,and *** convergence of these fields has resulted in the development of nanotransducers,devices that harness the synergies of these diverse *** nanotransducers,essential for neuromodulation,often draw inspiration from energy conversion processes found in nature for their unique *** this review,we will delve into the latest advancements in wireless neuromodulation facilitated by optical,magnetic,and mechanical *** will examine their working principles,properties,advantages,and limitations in comparison to current methods for deep brain neuromodulation,highlighting the impact of natural systems on their design and ***,we will underscore potential future directions,emphasizing how continued progress in materials science,neuroscience,and bioengineering might expand the horizons of what is achievable with nanotransducer-enabled neuromodulation.

关键词： bioinspired synthesis neuromodulation mechanoluminescence focused ultrasound nanotransducers sono-optogenetics

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基于迁移学习的滚动轴承剩余使用寿命预测

哈尔滨工程大学学报 2024年第4期45卷 665-673页

作者：姜苗向阳魏建红武汉理工大学船海与能源动力工程学院湖北武汉430000 高性能船舶技术教育部重点实验室(武汉理工大学) 湖北武汉430000

为解决轴承剩余使用寿命预测模型预测泛化能力低,不能准确预测出未训练轴承剩余使用寿命的问题,本文提出了一种迁移轴承状态知识的剩余使用寿命的方法。利用计算时域、频域特征以及模糊熵作为预测特征,使用“3σ”准则将轴承全寿命过程... 详细信息

为解决轴承剩余使用寿命预测模型预测泛化能力低,不能准确预测出未训练轴承剩余使用寿命的问题,本文提出了一种迁移轴承状态知识的剩余使用寿命的方法。利用计算时域、频域特征以及模糊熵作为预测特征,使用“3σ”准则将轴承全寿命过程划分为正常阶段、退化阶段,以实现对退化阶段轴承剩余使用寿命的预测。构建基于门控循环单元的轴承剩余使用寿命预测模型,并使用某一轴承的全寿命周期数据进行训练,使模型学习到新轴承的状态信息。研究表明:相较于未使用迁移学习的方法,其预测所有轴承的轴承剩余使用寿命平均均方根误差减小了52.53%,平均百分比误差减少了68.87%。本文提出的方法可以有效、准确地预测出轴承的轴承剩余使用寿命。

关键词：门控循环单元剩余使用寿命预测滚动轴承迁移学习预训练模糊熵退化阶段特征融合

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E-MobileNeXt: face expression recognition model based on improved MobileNeXt

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Optoelectronics Letters 2024年第2期20卷 122-128页

作者： ZHANG xiang YAN Chunman School of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China1

In response to the high complexity and low accuracy of current facial expression recognition networks, this paper proposes an E-Mobile Ne Xt network for facial expression recognition. E-Mobile Ne Xt is built based on our proposed E-Sand Glass block. In addition, we also improve the overall performance of the network through Rep Conv and SGE attention mechanisms. The experimental results show that the network model improves the expression recognition accuracy by 6.5% and 7.15% in RAF-DB and CK+ datasets, respectively, while the parameter and floating-point operations decreased by 0.79 M and 4.2 M compared with Mobile Ne Xt.

关键词： facial mechanisms. network

Precipitating thermally reinforcement phase in aluminum alloys for enhanced strength at 400℃

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Journal of Materials Science & Technology 2024年第5期172卷 71-82页

作者： xiang Su Yuan Lei Yang Chen Hongjie Qu Zhixiang Qi Gong Zheng Xu Liu Henggao xiang Guang Chen National Key Laboratory of Advanced Casting Technologies MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials TechnologyEngineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing 210094China School of Aviation and Mechanical Engineering Changzhou Institute of TechnologyChangzhou 213032China

Heat-resistant aluminum alloys are widely used in aerospace and automotive fields for manufacturing hot components due to their advantages in lightweight design and energy ***,the high-temperature strength of existing cast aluminum alloys is always limited to about 100 MPa at 350℃due to coarsening and transformation of strengthening ***,we reveal that the yield strength and ultimate tensile strength of the T6 state Al-8.4Cu-2.3Ce-1.0Mn-0.5Ni-0.2Zr alloy at 400◦C increase by 34%and 44%after re-aging at 300℃for 100 h,and its thermal strength exhibits distinguished ad-vantage over traditional heat-resistant aluminum *** enhanced elevated-temperature strength is attributed to the reprecipitation of the Ni-bearing T-Al_(20)Cu_(2)Mn_(3)phase,whose number density increases over one *** significant segregation of Ni,Ce,and Zr elements at the interfaces helps improve the thermal stability of the T *** thermostable T phase effectively strengthens the matrix by in-hibiting dislocation ***,a highly interconnected 3D intermetallic network along the grain boundaries can still remain after long-term re-aging at 300℃,which is conducive to imposing a drag on the grain boundaries at high *** finding offers a viable route for enhancing the elevated-temperature strength of heat-resistant aluminum alloys,which could provide expanded opportunities for higher-temperature applications.

关键词： Aluminum alloys Precipitation Thermally reinforcement phase Re-aging treatment High-temperature strength

Probiotics intervention in colorectal cancer:From traditional approaches to novel strategies

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Chinese Medical Journal 2024年第1期137卷 8-20页

作者： Suki Ha xiang Zhang Jun Yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesThe Chinese University of Hong KongHong Kong SARChina

The intestine harbors a large population of microorganisms that interact with epithelial cells to maintain host healthy physiological *** intestinal microbiota engage in the fermentation of non-digestible nutrients and produce beneficial metabolites to regulate host homeostasis,metabolism,and immune *** disruption of microbiota,known as dysbiosis,has been implicated in many intestinal diseases,including colorectal cancer(CRC).As the third most common cancer and the second leading cause of cancer-related death worldwide,CRC poses a significant health *** is an urgent need for novel interventions to reduce CRC incidence and improve clinical *** the intestinal microbiota has emerged as a promising approach for CRC prevention and *** research efforts in CRC probiotics primarily focus on reducing the incidence of CRC,alleviating treatment-related side effects,and potentiating the efficacy of anticancer therapy,which is the key to successful translation to clinical *** paper aims to review the traditional probiotics and new interventions,such as next-generation probiotics and postbiotics,in the context of *** underlying mechanisms of probiotic anti-cancer effects are also discussed,including the restoration of microbial composition,reinforcement of gut barrier integrity,induction of cancer cell apoptosis,inactivation of carcinogens,and modulation of host immune *** paper further evaluates the novel strategy of probiotics as an adjuvant therapy in boosting the efficacy of chemotherapy and *** all the promising findings presented in studies,the evaluation of potential risks,optimization of delivery methods,and consideration of intra-patient variability of gut microbial baseline must be thoroughly interpreted before bench-to-bedside translation.

关键词： colorectal cancer probiotics gut microbiota dysbiosis adjuvant therapy immune modulation gut barrrier