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Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo Ze-long liang Yue-E Jiao Hang Xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

Heterochronous multiple primary prostate cancer and lymphoma:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1333-1338页

作者： Jin-long liang Yu-Qing Bu Li-Li Peng Hong-Zhen Zhang Department of Oncology Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Multiple primary malignant tumors(MPMTs)are rare type of cancer,especially when solid tumors are the first and lymphoma is the second primary *** report a patient with heterochronous MPMTs consisting of prostate cancer and rectal diffuse large B-cell lymphoma(DLBCL).CASE SUMMARY We report a 77-year-old male patient diagnosed with prostate cancer who was treated with radiation therapy and one year of endocrine therapy with bicalutamide(50 mg per day)and an extended-release implant of goserelin(1/28 d).Seven years later,rectal DLBCL with lung metastases was *** Although rare,the possibility of prostate cancer combined with a double primary cancer of DLBCL can provide a deeper understanding.

关键词： Multiple primary malignant tumors Radiation therapy Diffuse large B-cell lymphoma Prostate cancer Non-Hodgkin lymphoma Case report

Hollow structured Fe@C nanorods for boosting dehydrogenation properties of α-AlH_(3)

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Nano Research 2024年第9期17卷 8184-8191页

作者： Yuan Zhao Qingshuang Wang Dongming Yin Xiaoli Wang Shouliang Li Chunli Wang long liang Shaolei Zhao Limin Wang Yong Cheng School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shandong Provincial Key Laboratory of Monocrystalline Silicon Semiconductor Materials and Technology College of Chemistry and Chemical EngineeringDezhou UniversityDezhou 253023China Henan Nayu New Material Co. Ltd.Xinxiang 453000China

α-AlH_(3)is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity(10.1 wt.%,148 kg·m^(-3)).However,in practical applications,the associated hydrogen release temperature remains relatively *** effectively address this issue,hollow structured Fe@C nanorods derived from Fe-MOF are introduced as highly efficient catalyst to optimize the dehydrogenation properties ofα-AlH_(3).Comparatively,the initial hydrogen release temperature ofα-AlH_(3)+3 wt.%Fe@C is reduced to 94.2℃,which is significantly lower than that of pureα-AlH_(3)(137.8℃).At 100 and 120℃,it exhibits hydrogen capacities of 5.38 wt.%and 7.47 wt.%,respectively,whereas pureα-AlH_(3)only delivers hydrogen capacities of 0.24 wt.%and 5.94 wt.%under the same *** density functional theory(DFT)calculations further indicate that the existence of Fe@C catalyst can make the length of Al-H bond increase,which is more conducive to the release of *** results show that the synergistic effect of Fe and porous carbon in Fe@C nanorods can improve the hydrogen desorption kinetics ofα-AlH_(3),providing a good prospect for the application ofα-AlH_(3)in hydrogen storage fields.

关键词： Fe@C α-AlH_(3) dehydrogenation catalyst

Multidimensional regulation of Ti-Zr-Cr-Mn hydrogen storage alloys via Y partial substitution

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Nano Research 2024年第5期17卷 4211-4220页

作者： Haixiang Xiu Wanqiang Liu Dongming Yin Nan Ding Wenfeng Qiao Shaolei Zhao long liang Cong Liu Shaohua Wang Qingshuang Wang Bingbing Chen Limin Wang Yong Cheng School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of Sciences(CAS)Changchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy GRINM Group Co.Ltd.Beijing 100088China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China College of Life Science and Technology Changchun University of Science and TechnologyChangchun 130022China

High density and safe storage of hydrogen are the preconditions for the large-scale application of hydrogen ***,the hydrogen storage properties of Ti_(0.6)Zr_(0.4)Cr_(0.6)Mn_(1.4) alloys are systematically studied by introducing Y element instead of Ti element through vacuum arc *** the partial substitution of Y,a second phase of rare earth oxide is added in addition to the main suction hydrogen phase,C14 Laves *** to the unique properties of rare earth elements,the partial substitution of Y can not only improve the activation properties and plateau pressure of the alloys,but also increase the effective hydrogen storage capacity of the *** comprehensive properties of hydrogen storage alloys are improved by multidimensional regulation of rare earth *** them,Ti_(0.552)Y_(0.048)Zr_(0.4)Cr_(0.6)Mn_(1.4) has the best comprehensive *** alloy can absorb hydrogen without activation at room temperature and 5 MPa,with a maximum hydrogen storage capacity of 1.98 wt.%.At the same time,it reduces the stability of the hydride and the enthalpy change value,making it easier to release *** theoretical analysis and first-principle simulation,the results show that the substitution of Y element reduces the migration energy barrier of hydrogen and the structural stability of the system,which is conducive to hydrogen *** alloy has superior durability compared to the original alloy,and the capacity retention rate was 96.79%after 100 hydrogen absorption/desorption cycles.

关键词： AB_(2)-type hydrogen storage alloy rare earth element first-principles simulation multidimensional regulation

Exceptional points and quantum dynamics in a non-Hermitian two-qubit system

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Chinese Physics B 2024年第6期33卷 212-218页

作者：张益玺张振涛杨震山魏晓志梁宝龙 School of Physics Science and Information Technology Shandong Key Laboratory of Optical Communication Science and TechnologyLiaocheng UniversityLiaocheng 252059China

We study the exceptional-point(EP) structure and the associated quantum dynamics in a system consisting of a non-Hermitian qubit and a Hermitian qubit. We find that the system possesses two sets of EPs, which divide the systemparameter space into PT-symmetry unbroken, partially broken and fully broken regimes, each with distinct quantumdynamics characteristics. Particularly, in the partially broken regime, while the PT-symmetry is generally broken in the whole four-dimensional Hilbert space, it is preserved in a two-dimensional subspace such that the quantum dynamics in the subspace are similar to those in the PT-symmetry unbroken regime. In addition, we reveal that the competition between the inter-qubit coupling and the intra-qubit driving gives rise to a complex pattern in the EP variation with system parameters.

关键词： non-Hermitian system exceptional point PT-symmetry

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小学班级家长群信息交流的五个维度

教学与管理 2024年第8期 17-21页

作者：梁龙谢娟济南大学教育与心理科学学院

班级家长群在数字媒介的支持下已成为小学家校协同育人的重要信息交流平台。SMCR模式系统分析了信息交流过程,阐释了影响信息交流的关键因素,并以SMCR模式为基础,从五个维度探析提升班级家长群信息交流效率和质量的路径。在信源维度,优... 详细信息

班级家长群在数字媒介的支持下已成为小学家校协同育人的重要信息交流平台。SMCR模式系统分析了信息交流过程,阐释了影响信息交流的关键因素,并以SMCR模式为基础,从五个维度探析提升班级家长群信息交流效率和质量的路径。在信源维度,优化信息把关力度,提升教师的信息交流素养与影响力;在信息维度,优化信息成分与结构,提高符号处理的适宜性;在信道维度,选择适合的交流渠道,避免通道间的冲突与干扰;在受传者维度,提升家长信息交流素养,培养理性参与意识;在噪声及反馈维度,消除噪声干扰,强化反馈机制。

关键词：小学班级家长群 SMCR 信息交流

结合深度强化学习的边缘计算网络服务功能链时延优化部署方法

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电子与信息学报 2024年第4期46卷 1363-1372页

作者：孙春霞杨丽王小鹏龙良兰州交通大学电子与信息工程学院兰州730070

该文针对边缘网络资源受限且对业务流端到端时延容忍度低的问题,结合深度强化学习与基于时延的Dijkstra寻路算法提出一种面向时延优化的服务功能链(SFC)部署方法。首先,设计一种基于注意力机制的序列到序列(Seq2Seq)代理网络和基于时延... 详细信息

该文针对边缘网络资源受限且对业务流端到端时延容忍度低的问题,结合深度强化学习与基于时延的Dijkstra寻路算法提出一种面向时延优化的服务功能链(SFC)部署方法。首先,设计一种基于注意力机制的序列到序列(Seq2Seq)代理网络和基于时延的Dijkstra寻路算法,用于产生虚拟网络功能(VNF)的部署以及服务SFC的链路映射,同时考虑了时延优化模型的约束问题,采用拉格朗日松弛技术将其纳入强化学习目标函数中;其次,为了辅助网络代理快速收敛,采用基线评估器网络评估部署策略的预期奖励值;最后,在测试阶段,通过贪婪搜索及抽样技术降低网络收敛到局部最优的概率,从而改进模型的部署。对比实验表明,该方法在网络资源受限的情况下,比First-Fit算法与TabuSearch算法的时延分别降低了约10%和86.3%,且较这两种算法稳定约74.2%与84.4%。该方法能较稳定地提供更低时延的端到端服务,使时延敏感类业务获得更好体验。

关键词：服务功能链部署深度强化学习边缘网络端到端时延

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煤气化渣资源化利用综述

煤炭科学技术 2024年第8期52卷 192-208页

作者：高海洋梁龙靳开宇谭佳琨中国矿业大学化工学院江苏徐州221116 山东能源集团物资有限公司山东济南250000

随着“双碳”目标的推进,社会对煤气化渣处理的关注与需求日渐紧迫。综合过往研究,介绍了煤气化渣的主要来源与排渣方式,并分别对比了粗渣与细渣在形貌、粒度组成、矿物物相、化学组成等方面的性质特点,为实现其“减量化、资源化、无害... 详细信息

随着“双碳”目标的推进,社会对煤气化渣处理的关注与需求日渐紧迫。综合过往研究,介绍了煤气化渣的主要来源与排渣方式,并分别对比了粗渣与细渣在形貌、粒度组成、矿物物相、化学组成等方面的性质特点,为实现其“减量化、资源化、无害化”利用提供了理论依据。基于气流床煤气化粗渣、细渣显著的性质差异,探索了两者不同的资源化处理方式,并分析了当下利用途径存在的局限性。粗渣具有优秀的水化活性与火山灰活性,在矿井回填、路基填筑、水泥与混凝土骨料、陶粒材料以及墙体材料等中低值利用领域应用广泛,但存在重金属浸出风险、经济效益低等问题。细渣中残炭含量丰富,主要采用重选法与浮选法进行可燃体回收与灰渣分离。但其较高的细粒级含量降低了重选分选精度,复杂的炭-灰结合形态提高了浮选回收难度。同时细渣孔隙结构发达,比表面积高达258.29 m^(2)/g,具有一定的吸附能力,在土壤改良、催化剂载体、化工原料、陶瓷材料、吸附材料等领域应用潜力巨大,但高值化处理工艺复杂,成本较高,工业应用难度较大。针对这些问题,需基于煤气化渣的物化性质,探索大规模消纳与高值化利用相结合的途径,实现对煤气化渣分类分级的资源化利用。此外,需结合现场生产实践,探索煤气化渣就地解决的处理方法以降低运输成本,以及在其产生工艺过程中进行物化性质的诱导改善处理。

关键词：煤基固废煤气化渣气流床工艺可燃体回收资源化利用

自浸润式纳米压印耦合实现量子点发光二极管性能提升

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发光学报 2024年第4期45卷 613-620页

作者：梁龙郑悦婷林立华胡海龙李福山福州大学物理与信息工程学院福建福州350106

胶体量子点材料因其优良的窄发射光谱、可调发射波长、高发光效率和优异的稳定性而被广泛研究,且同时具有溶液可加工性使得量子点发光二极管(Quantum dot light-emitting diode,QLED)具有广泛的适用性和应用。然而,器件自身存在的基底... 详细信息

胶体量子点材料因其优良的窄发射光谱、可调发射波长、高发光效率和优异的稳定性而被广泛研究,且同时具有溶液可加工性使得量子点发光二极管(Quantum dot light-emitting diode,QLED)具有广泛的适用性和应用。然而,器件自身存在的基底模式导致QLED器件大量光子被限制在内部无法利用。本文基于纳米压印工艺同时利用聚二甲基硅氧烷(Polydimethylsiloxane,PDMS)材料本身的表面结合能开发出溶剂自浸润式纳米压印工艺,对压力依赖度低的同时简化了工艺流程,制备出高质量周期性的1.3,1,0.5μm三种尺寸的微纳结构图案层,对红、绿、蓝三色QLED器件进行耦合实现光提取。在这种情况下,1.3μm微纳结构耦合绿光QLED器件亮度达到715069 cd·m^(-2),最大外量子效率(External quantum efficiency,EQE)和电流效率分别提升至12.5%和57.3 cd·A^(-1);1μm尺寸耦合的蓝光QLED器件各电学性能提升接近200%;0.5μm尺寸耦合红光QLED器件EQE也从17.3%提升至20.5%。并通过角分布测试,证明微纳结构不会对QLED器件发光强度造成影响,仍然接近朗伯体发射。本工作提出的溶剂自浸润式纳米压印工艺及QLED光提取方法,为QLED的性能提升提供了一条简单有效的途径。

关键词：量子点发光二极管纳米压印耦合光学性能光学仿真

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