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Porous organic cages as a novel platform for second harmonic generation

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Science China Chemistry 2024年第11期67卷 3669-3674页

作者： Feng Shui Yunqin zhang Mao Yi Xiongli liu lin li Shuo zhang Yongshen Zheng Yongtao Yao qiao Zhao Baiyan li Xianhe Bu School of Materials Science and Engineering National Institute for Advanced Materials TKL of Metal and Molecule-Based Material Chemistry Nankai University National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology

Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular crystals and organic polymers, have been extensively explored for SHG optics due to their advantageous properties, including high light-induced damage threshold, ultrafast response speed, high polarization ratio, wide transparency range, and elevated dielectric constant. However,in organic SHG materials, most small molecular crystals often show poor thermal stability(lication under high temperatures. On the other hand, the difficulty in the growth of large-size crystals as well as the disorderly array of chromospheres on polymer chains associated with organic polymers have hindered their widespread application in SHG due to the requirements of processability and ***, it is significantly necessary to develop novel organic SHG material with high thermal stability, large-size crystals,excellent processability, high homogeneity, and a well SHG effect. In the contribution, we developed herein porous organic cages(POCs) as a novel platform for SHG optics. Thanks to its inherent macromolecular composition and zero-dimensional discrete structures, POCs can not only solve the instability problem of small molecule crystals but also overcome the drawbacks in growing large-size crystals for organic polymer. The obtained two POCs with chiral asymmetric centers(CPOC-R-5 and CPOCS-7) display advantageous features for SHG optics including well SHG performance, large-size crystal(5 mm×3 mm×1 mm),high thermal stability(≥250 °C), wide transparency window(750–2,000 nm) and high polarization ratio(up to 94.5%). This work thus develops POCs as a new platform toward the construction of organic NLO materials with the potential application in sorts of SHG optics.

关键词： porous organic cages second harmonic generation novel SHG platform high thermal stability large-size single crystal

Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy

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China Foundry 2024年第3期21卷 213-220页

作者： Ji-peng li De-gao qiao Jian li Xiao-yang Luo Peng Peng Xian-tao Yan Xu-dong zhang Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735111GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China

The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich *** addition,the primary Al dendrites show significant refinement with an increase in the withdrawal *** relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 *** is a combined effect of grain refinement and second-phase strengthening.

关键词： Galvalume alloy directional solidification microstructure length scale microhardness

Monte Carlo method for evaluation of surface emission rate measurement uncertainty

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Nuclear Science and Techniques 2024年第7期35卷 126-136页

作者： Yuan-qiao li Min lin li-Jun Xu Rui Luo Yu-He zhang Qian-Xi Ni Yun-Tao liu China Institute of Atomic Energy Beijing102413China National Key Laboratory for Metrology and Calibration Techniques Beijing102413China Department of Radiation Oncology Hunan Cancer HospitalChangsha410031China The Affiliated Cancer Hospital of Xiangya School of Medicine Central South UniversityChangsha410031China

The aim of this study is to evaluate the uncertainty of 2πα and 2πβ surface emission rates using the windowless multiwire proportional counter *** study used the Monte Carlo method (MCM) to validate the conventional Guide to the Expression of Uncertainty in Measurement (GUM) method.A dead time measurement model for the two-source method was established based on the characteristics of a single-channel measurement system,and the voltage threshold correction factor measurement function was indirectly obtained by fitting the threshold correction *** uncertainty in the surface emission rate was calculated using the GUM method and the law of propagation of *** MCM provided clear definitions for each input quantity and its uncertainty distribution,and the simulation training was realized with a complete and complex mathematical *** results of the surface emission rate uncertainty evaluation for four radioactive plane sources using both methods showed the uncertainty’s consistency E_(n)lidation tool for GUM results.

关键词： Surface emission rate Monte Carlo method Metrology Probability distribution function Dead time Low-energy loss correction Least-squares method

Preparation of crab-shell-based N,O co-doped graded porous carbon for supercapacitors using the confined nanospace deposition

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Waste Disposal and Sustainable Energy 2024年第2期6卷 173-183页

作者： Yiming li Zhihao Yu Mengyan Guo Ming zhang Jian Xiong Yina qiao Rui zhang Xuebin Lu School of Environmental Science and Engineering Tianjin UniversityTianjin 30000China School of Ecology and Environment Tibet UniversityLhasa 850000China School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China School of Environmental and Municipal Engineering Tianjin Chengjian UniversityTianjin 300384China

Biomass-based carbon materials with hierarchical porous structures have attracted attention for their ability to provide more channels and shorten ion transport ***,we developed a simple method based on confined nanospace ***-ing high-temperature treatment,the mesoporous silica layer wrapped around the outside of the crab shells acted as a closed nanospace and effectively suppressed the severe deformation of the crab shell structure by shrinking *** prepared carbon material has a layered porous structure with abundant and stable N and O co-doping(N 7.32%,O 3.69%).The specific capacitance of the three-electrode system was 134.3 F/g at a current density of 0.5 A/g in a 6 mol/L KOH electrolyte,and the assembled aqueous symmetric supercapacitors exhibited an excellent cycling stability of 98.81%even after 5000 cycles.

关键词： Supercapacitor Confined nanospace deposition Biomass-based carbon materials Crab shell

Identification and functional verification of Y-chromosome-specific gene typo-gyf in Bactrocera dorsalis

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Insect Science 2024年第4期31卷 1270-1284页

作者： Peipei liu Shuning Yu Wenping Zheng Qiuyuan zhang Jiao qiao Ziniu li Zhurong Deng Hongyu zhang National Key Laboratory for Germplasm Innovation and Utilization for Fruit and Vegetable Horticultural Crops Hubei Hongshan LaboratoryChina-Australia Joint Research Centre for Horticultural and Urban PestsInstitute of Urban and Horticultural EntomologyCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina

Genes on the Y chromosome play important roles in male sex determination and *** identification of Y-chromosome-specific genes not only provides a theoretical basis for the study of male reproductive development,but also offers genetic control targets for agricultural ***,Y-chromosome genes are rarely characterized due to their high repeatability and high heterochromatinization,especially in the oriental fruit *** this study,1011 Y-chromosome-specific candidate sequences were screened from 2 to 4 h Bactrocera dorsalis embryo datasets with the chromosome quotient method,6 of which were identified as Y-chromosome-specific sequences by polymerase chain reaction,including typo-gyf,a 19126-bp DNA sequence containing a 575-amino acid open reading *** deformation and a significant reduction in sperm number were observed after typo-gyf knockdown with RNA interference in *** typo-gyf knockout with clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 in the embryonic stage,the sex ratio of the emergent adults was unbalanced,with far more females than males.A genotype analysis of these females with the Y-chromosome gene MoY revealed no sex ***-gyf knockout led to the death of XY individuals in the embryonic *** conclude that typo-gyf is an essential gene for male survival,and is also involved in testicular development and *** identification of typo-gyf and its functional verification provide insight into the roles of Y-chromosome genes in male development.

关键词： Bactrocera dorsalis spermatogenesis testis typo-gyf gene Y-specific gene

Advanced strategies for 3D-printed neural scaffolds:materials,structure,and nerve remodeling

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Bio-Design and Manufacturing 2024年第5期7卷 747-770页

作者： Jian He liang qiao Jiuhong li Junlin Lu Zhouping Fu Jiafang Chen Xiangchun zhang Xulin Hu College of Basic Medicine and Forensic Medicine Henan University of Science and TechnologyLuoyang 471023China The First Affiliated Hospital College of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471003China Tea Research Institute Chinese Academy of Agricultural SciencesHangzhou 310008China Clinical Medical College Affiliated Hospital of Chengdu UniversityChengdu UniversityChengdu 610081China Department of Cardiovascular Surgery Department of BiotherapyCancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China Department of Neurosurgery West China HospitalSichuan UniversityChengdu 610041China

Nerve regeneration holds significant potential in the treatment of various skeletal and neurological disorders to restore lost sensory and motor *** potential of nerve regeneration in ameliorating neurological diseases and injuries is critical to human ***-dimensional(3D)printing offers versatility and precision in the fabrication of neural *** neural structures such as neural tubes and scaffolds can be fabricated via *** reviewcomprehensively analyzes the current state of 3D-printed neural scaffolds and explores strategies to enhance their *** highlights therapeutic strategies and structural design involving neural materials and stem ***,nerve regeneration materials and their fabrication techniques are *** applications of conductive materials in neural scaffolds are reviewed,and their potential to facilitate neural signal transmission and regeneration is ***,the progress in 3D-printed neural scaffolds applied to the peripheral and central nerves is comprehensively evaluated,and their potential to restore neural function and promote the recovery of different nervous systems is *** addition,various applications of 3D-printed neural scaffolds in peripheral and neurological diseases,as well as the design strategies of multifunctional biomimetic scaffolds,are discussed.

关键词： Nerve regeneration 3D printing based neural scaffolds Biomaterials Nervous system Design strategies

Oxidative Dehydrogenation of Propane over Supported Nickel Single-Atom Catalyst

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Chinese Journal of Chemistry 2024年第4期42卷 370-376页

作者： Qian zhang Xunzhu Jiang Yangyang li Yuanlong Tan Qike Jiang Xiaoyan liu Botao qiao CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning116023 China University of Chinese Academy of Sciences Beijing100049 China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning116023 China

Oxidative dehydrogenation of propane has been an ever-growing field for propylene production due to its exothermic properties,of which overoxidation is the major drawback,with CO and even CO_(2) as undesired *** the purpose of getting higher propylene selectivity as well as yield,herein,we report Ni single atoms supported on calcium aluminate as an efficient catalyst candidate for propane oxidative *** from higher valence states of Ni1 species,it shows 2—3 times as much propylene selectivity as that of Ni *** 14.2%C_(3)H_(6) yield with 47.3%propylene selectivity has been achieved on Ni single atom catalyst and a good stability during 20 h test can be obtained as well.

关键词： Oxidative dehydrogenation/Nickel Single-atom catalysts Propane Propylene selectivity

Simultaneous enhancement of red luminescence and thermal stability of a novel red phosphor:A li^(+)-Eu^(3+)co-occupied site strategy in BaAl_(2)Ge_(2)O_(8)lattices

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Journal of Rare Earths 2024年第10期42卷 1846-1854页

作者： Wei zhang Changjian Wang Xusheng qiao Xianping Fan State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Ocean Academy Zhejiang UniversityZhoushan316021China

The rapid development of phosphor-converted white light emitting diodes(pc-WLEDs)requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white ***,it is still a challenge to discover red phosphors with facile synthesis,high internal quantum efficiency(IQE),excellent thermal stability and high color ***,a novel red-emitting Eu^(3+)activated barium dialuminum digermanate(BaAl_(2)Ge_(3)O_(8),EAGO)phosphor showing strong red emission at 610 nm was *** IQE is improved from 32.91%to 78.84%by employing a charge compensation *** lithium-ion co-dop ed BAGO:Eu^(3+)phosphor exhibits a nearly twofold increase in integral photoluminescence(PL)intensity and the high color purity reaches 94.17%.Impressively,the PL intensity of the BAGO:Eu^(3+),li^(+)phosphor drops by only 2.6%at 150℃of that at room ***,the pc-WLED using the red BAGO:Eu^(3+),li^(+)phosphor exhibits white light with the chromaticity coordinate of(0.3515,0.3495),a high color-rendering index of 92 and a low correlated color temperature of 4746 *** these results manifest that BAGO:Eu^(3+),li^(+)phosphor is a suitable red phosphor for nearultraviolet(NUV)chip-based pc-WLEDs.

关键词： BaAl_(2)Ge_(2)O_(8):Eu^(3+) Red phosphor Charge compensation High quantum efficiency Excellent thermal stability Rare earths

Atomic multicast protocol for intrusion-tolerance based on trusted timely computing base

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 97-102页

作者： ZHOU Hua,MENG Xiang-ru,zhang li,qiao Xiang-dong Telecommunication Engineering Institute,Air Force Engineering University,Xi’an 710077,China Telecommunication Engineering Institute Air Force Engineering University Xi'an 710077 China

Distributed architecture is often adopted for the intrusion-tolerance system ***,this distributed intrusiontolerance system has a consensus *** solve this problem,this article explores a distributed intrusion-tolerance system of hybrid time model based on trusted timely computing base（TTCB） and implement an atomic multicast protocol using TTCB *** TTCB is a trust secure real-time component inside the server,with a well defined interface and separated from the operation *** is in the synchronous communication environment,while the application layer in the server works *** the atomic multicast protocol,it can be achieved that when the servers are over twice the number of faulty servers,the consensus can be *** performance evaluations show that the proposed protocol can yield larger good throughput with a lower unavailability.

关键词： Intrusion-tolerance atomic multicast protocol consensus TTCB network security