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Antifungal variant bis(bibenzyl)s from the liverwort Asterella angusta

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Chinese Chemical Letters 2013年第9期24卷 801-803页

作者： Jian-Bo Qu ling-mei sun Hong-Xiang Lou School of Pharmaceutical Sciences Shandong University Center for Drug Evaluation SFDA

Bioassay-guided fractionation of the diethyl ether extract of the liverwort Asterella angusta led to the isolation of two antifungal bis（bibenzyl）s, riccardin I （1）, and angustatin A （2）. Their structures were established by spectroscopic analysis （1D NMR and 2D NMR, IR, MS）. Compound I is a novel variant riccardin-type bis（bibenzyl）, while compound 2 is the first nonheteratom-containing variant bis（bibenzyl） possessing a bibenzyl-phenanthrene skeleton.

关键词： Variant bis(bibenzyl)s Asterella angusta Antifungal activity

Strategies and challenges for enhancing performance of MXene-based gas sensors:a review

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Rare Metals 2022年第12期41卷 3976-3999页

作者： Hai-Feng Zhang Jing-Yue Xuan Qi Zhang mei-ling sun Fu-Chao Jia Xiao-mei Wang Guang-Chao Yin Si-Yu Lu School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China

With the advantages of metal conductivity,large specific surface area,and rich surface functional groups,two-dimensional(2D)MXenes have shown great potential in the field of gas ***,gas sensors fabricated with pristine MXenes generally suffer from several problems such as low sensitivity,poor selectivity,significant baseresistance drift,and poor environment ***,many efforts have been devoted to overcoming these *** this review,we review the progress on MXenebased gas sensors and summarize several efficient strategies(including structural design,surface modification,inorganic Schottky j unction/heterojunction sensitization,polymer addition,and metal-ion intercalation)to promote the gassensing *** addition,the major challenges and future development directions of MXene-based gas sensors are also outlined in the present review.

关键词： MXenes Gas sensors Strategies Gas-sensing performance

Multiple thermal events recorded in the Acasta Gneiss Complex:Evidence from in-situ dating of zircon, titanite, and apatite

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Science China Earth Sciences 2024年第3期67卷 673-686页

作者： Qingfeng mei Jinhui YANG Jinfeng sun Qiuli LI Shitou WU Xiaoxiao ling Peng PENG Hao WANG State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China

In-situ dating of the zircons, titanites, and apatites in the rock fragments of approximately 1 cm2in size from the Acasta Gneiss Complex was performed using secondary ion mass spectrometry or laser ablation inductively coupled plasma mass spectrometry to provide constraints on the thermal history of the Acasta Gneiss Complex. The zircons in these rock fragments typically exhibit multiple age populations, reflecting the presence of inherited zircons or the post-crystallization process of zircon overgrowth. Combined with previous studies, our zircon dating results reveal multiple magmatic events that occurred in the Acasta Gneiss Complex, specifically at >3.96, ~3.72, and ~3.57 Ga, respectively. A titanite Pb-Pb isochron age of2911±22 Ma(95% confidence level, MSWD=1.5) for sample AY199 is identified, consistent with the timing of the latest Archean magmatism in the Acasta Gneiss Complex. The titanite U-Pb ages for samples AC478 and AY066 are 1932±270 Ma(95% confidence level, MSWD=2.3) and 1813±45 Ma(95% confidence level, MSWD=2.3), respectively. The apatites in sample P090803-C exhibit a Pb-Pb isochron age of 1833±26 Ma(95% confidence level, MSWD=1.4). The apatite U-Pb ages for samples AC478, AY199, and AY066 are 1850±20 Ma(95% confidence level, MSWD=1.3), 1827±100 Ma(95% confidence level, MSWD=6.3), and 1807±58 Ma(95% confidence level, MSWD=3.9), respectively. Titanites in samples AC478 and AY066, as well as the apatites in all four investigated samples, show a uniform age(Pb-Pb or U-Pb age) of ~1.9–1.8 Ga,indicating U-Pb system reset in these minerals due to the Wopmay orogeny and documenting that the peak temperature condition associated with the Wopmay orogeny exceeded the apatite U-Pb closure temperature and approached or exceeded that of titanite.

关键词： Zircon Titanite Apatite Acasta Gneiss Complex Wopmay Orogen

Low-temperature synthesis of apatite-type La_(9.33)Ge_6O_(26) as electrolytes with high conductivity

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Chinese Physics B 2018年第4期27卷 520-525页

作者： Guang-Chao Yin Guo-Dong Zhao Hong Yin Fu-Chao Jia Qiang Jing Sheng-Gui Fu mei-ling sun Wei Gao Laboratory of Functional Molecular Materials School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo 255000 China State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China

In the present study,high-quality apatite-type La9.33Ge6O26 powders are successfully synthesized by a facile moltensalt synthesis method（MSSM） at low temperatures,using Li Cl,Li Cl/Na Cl mixture（mass ratio 1：1） as molten salt,*** results indicate that the optimal mass ratio between reactant and molten salt is 1：2,and Li Cl/Na Cl mixed molten-salt is more beneficial for forming high-quality La9.33Ge6O26 powders than Li Cl individual *** with the conventional solid-state reaction method（SSRM）,the synthesis temperature of apatitetype La9.33Ge6O26 powders using the MSSM decreases more than 350℃,which can effectively avoid Ge loss in the preparation process of precursor ***,the powders obtained by the MSSM are homogeneous,nonagglomerated and well crystallized,which are very favorable for gaining dense pellets in the premise of avoiding Ge *** the basis of high-quality precursor powders,the dense and pure ceramic pellets of La（9.33）Ge6O（26） are gained at a low temperature of 1100℃ for 2 h,which exhibit higher conductivities（σ850℃（Li Cl）= 2.3 × 10^-2 S·cm^-1,σ850 ℃（Li Cl/Na Cl） = 4.9 × 10^-2 S·cm^-1） and lower activation energies（Ea（Li Cl）= 1.02 e V,Ea（Li Cl/Na Cl）= 0.99 e V） than that synthesized by the SSRM.

关键词： solid oxide fuel cells electrolyte ionic conduction

High-quality CdS quantum dots sensitized ZnO nanotube array films for superior photoelectrochemical performance

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Chinese Physics B 2022年第9期31卷 561-569页

作者： Qian-Qian Gong Yun-Long Zhao Qi Zhang Chun-Yong Hu Teng-Fei Liu Hai-Feng Zhang Guang-Chao Yin mei-ling sun School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

The surface characteristics of ZnO were synthetically optimized by a self-designed simultaneous etching and W-doping hydrothermal method utilizing as-prepared ZnO nanorod(NR)array films as the *** from the etching and regrowth process and the different structural stabilities of the various faces of ZnO NRs,the uniquely etched and W-doped ZnO(EWZ)nanotube(NT)array films with larger surface area,more active sites and better energy band structure were used to improve the photoelectrochemical(PEC)performance and the loading quality of CdS quantum dots(QDs).On the basis of their better surface characteristics,the CdS QDs were uniformly loaded on EWZ NT array film with a good coverage ratio and interface connection;this effectively improved the light-harvesting ability,charge transportation and separation as well as charge injection efficiency during the PEC ***,all the CdS QD-sensitized EWZ NT array films exhibited significantly enhanced PEC *** CdS/EWZ-7 composite films exhibited the optimal photocurrent density with a value of 12 mA·cm^(-2),2.5 times higher than that of conventional CdS/ZnO-7 composite films under the same sensitization times with CdS *** corresponding etching and optimizing mechanisms were also discussed.

关键词： ZnO nanotubes W-doping CdS quantum dots

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Light(Science & Applications) 2024年第2期13卷 333-346页

作者： Yifan sun Qian Li ling-Jun Kong Xiangdong Zhang Key Laboratory of advanced optoelectronic quantum architecture and measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081BeijingChina

Compared with electrical neural networks,optical neural networks(ONNs)have the potentials to break the limit of the bandwidth and reduce the consumption of energy,and therefore draw much attention in recent *** far,several types of ONNs have been ***,the current ONNs cannot realize the acceleration as powerful as that indicated by the models like quantum neural *** to construct and realize an ONN with the quantum speedup is a huge ***,we propose theoretically and demonstrate experimentally a new type of optical convolutional neural network by introducing the optical *** is called the correlated optical convolutional neural network(COCNN).We show that the COCNN can exhibit“quantum speedup”in the training *** character is verified from the two *** is the direct illustration of the faster convergence by comparing the loss function curves of the COCNN with that of the traditional convolutional neural network(CNN).Such a result is compatible with the training performance of the recently proposed quantum convolutional neural network(QCNN).The other is the demonstration of the COCNN’s capability to perform the QCNN phase recognition circuit,validating the connection between the COCNN and the ***,we take the COCNN analog to the 3-qubit QCNN phase recognition circuit as an example and perform an experiment to show the soundness and the feasibility of *** results perfectly match the theoretical *** proposal opens up a new avenue for realizing the ONNs with the quantum speedup,which will benefit the information processing in the era of big data.

关键词： process quantum convolution

Heat transfer and temperature evolution in underground mininginduced overburden fracture and ground fissures: Optimal time window of UAV infrared monitoring

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International Journal of Mining Science and Technology 2024年第1期34卷 31-50页

作者： Yixin Zhao Kangning Zhang Bo sun Chunwei ling Jihong Guo Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and Technology-BeijingBeijing 100083China School of Energy&Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology-BeijingBeijing 100083China

Heat transfer and temperature evolution in overburden fracture and ground fissures are one of the essential topics for the identification of ground fissures via unmanned aerial vehicle(UAV) infrared imager. In this study, discrete element software UDEC was employed to investigate the overburden fracture field under different mining conditions. Multiphysics software COMSOL were employed to investigate heat transfer and temperature evolution of overburden fracture and ground fissures under the influence of mining condition, fissure depth, fissure width, and month alternation. The UAV infrared field measurements also provided a calibration for numerical simulation. The results showed that for ground fissures connected to underground goaf(Fissure Ⅰ), the temperature difference increased with larger mining height and shallow buried depth. In addition, Fissure Ⅰ located in the boundary of the goaf have a greater temperature difference and is easier to be identified than fissures located above the mining goaf. For ground fissures having no connection to underground goaf(Fissure Ⅱ), the heat transfer is affected by the internal resistance of the overlying strata fracture when the depth of Fissure Ⅱ is greater than10 m, the temperature of Fissure Ⅱ gradually equals to the ground temperature as the fissures’ depth increases, and the fissures are difficult to be identified. The identification effect is most obvious for fissures larger than 16 cm under the same depth. In spring and summer, UAV infrared identification of mining fissures should be carried out during nighttime. This study provides the basis for the optimal time and season for the UAV infrared identification of different types of mining ground fissures.

关键词： Heat transfer Overburden fracture Ground fissures Infrared thermal imaging Unmanned aerial vehicle(UAV) COMSOL simulation

In-situ fabrication of ZnO nanoparticles sensors based on gas-sensing electrode for ppb-level H_(2)S detection at room temperature

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Chinese Physics B 2021年第2期30卷 250-256页

作者： Jing-Yue Xuan Guo-Dong Zhao Xiao-Bo Shi Wei Geng Heng-Zheng Li mei-ling sun Fu-Chao Jia Shu-Gang Tan Guang-Chao Yin Bo Liu Laboratory of Functional Molecular and Materials School of Physics and Optoelectronic EngineeringShandong University of TechnologyZibo 255000China Institute of Artificial Intelligence Henan Finance UniversityZhengzhou 450046China

The zinc oxide(ZnO)nanoparticles(NPs)sensors were prepared in-situ on the gas-sensing electrodes by a one-step simple sol-gel method for the detection of hydrogen sulfide(H_(2)S)*** sphere-like ZnO NPs were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),x-ray diffraction(XRD),energy dispersive x-ray analysis(EDX),and their H_(2)S sensing performance were measured at room *** results indicate that the ZnO NPs exhibit excellent response to H_(2)S gas at room *** response value of the optimal sample to750 ppb H_(2)S is 73.3%,the detection limit reaches to 30 ppb,and the response value is 7.5%.Furthermore,the effects of the calcining time and thickness of the film on the gas-sensing performance were *** calcining time and film thickness show a negative correlation with the H_(2)S sensing *** corresponding reaction mechanism of H_(2)S detection was also discussed.

关键词： ZnO H_(2)S gas sensor room temperature

Research progress on short-term mechanical properties of FRP bars and FRP-reinforced concrete beams

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 245-270页

作者： Lili Xing Shengjiang sun Kuihua mei Yiping Guo Zhenhong Yang School of Highway Chang'an UniversityXi'an 710064China

Fiber-reinforced polymer(FRP)bars have been increasingly recognized in the field of civil engineering due to their advantages of light weight,high strength and excellent *** bars can replace steel bars in concrete beams and effectively improve the durability of *** this paper,the literature relevant to the short-term mechanical properties of FRP bars and FRP-reinforced concrete beams was reviewed based on previous studies and practical engineering ***,the mechanical properties of FRP bars were *** types of fibers or steel and fibers can be combined to obtain hybrid fiber-reinforced polymer(HFRP)or steel-fiber composite bars(SFCB)with excellent mechanical performance,*** bond performance and bond-slip model between FRP bars and concrete were *** common bond-slip models were usually used to study the bond performance between carbon fiber-reinforced polymer(CFRP)bars or glass fiber-reinforced polymer(GFRP)bars and concrete,but changing the type of FRP bars will lead to larger ***,the experimental studies,theoretical calculation methods and finite element simulation methods of flexural/shear behavior of FRP-reinforced concrete beams were ***,their applications in practical engineering were discussed and the prospects of further research were *** is pointed out that FRP-reinforced ultra-high performance concrete(UHPC)beams,FRP-reinforced geopolymer concrete(GPC)beams,engineered cementitious composites(ECC)-FRP-reinforced concrete beams,prestressed FRP-reinforced concrete beams and steel/FRP hybrid-reinforced concrete beams can effectively improve the deformation resistance and poor ductility of pure FRP-reinforced concrete beams.

关键词： FRP bars Bond performance Flexural/shear behavior Civil engineering