检索结果-南通市图书馆

Citrinal A,a novel tricyclic derivative of citrinin,from an algicolous fungus Penicillium sp.i-1-1

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第8期20卷 917-920页

作者： Tian Jiao Zhu Lin Du Peng Fei Hao Zhen Jian Lin qian qun gu Key Laboratory of Marine Drugs Chinese Ministry of Education School of Medicine and Pharmacy Ocean University of China Qingdao 266003 PR China

Citrinal A （1）, a novel tricyclic compound with a rare tetrahydro-2H-benzofuro[7-b] [ 1,4]dioxin-9（3H）-one skeleton, along with two known related compounds, citrinin （2） and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran （3） were isolated from an algicolous fungus Penicillium sp. i-1-1. The structure and stereochemistry of 1 were determined by comprehensive spectral and biogenic analysis. Its cytotoxic effects on the A-549 and HL-60 cell lines were evaluated. ？2009 qian qun gu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Citrinal Algicolous fungus Penicillium

A New Cytotoxic Compound from Penicillium auratiogriseum, Symbiotic or Epiphytic Fungus of Sponge Mycale plumose

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2005年第9期16卷 1227-1229页

作者： Zhi Hong XIN Wei Ming ZHU qian qun gu Yu Chun FANG Lin DUAN Cheng Bin CUI Key Laboratory of Marine Drugs of Chinese Ministry of Education Marine Drugs and Food Institute Ocean University of China Qingdao 266003

A new compound, （S）-2, 4-dihydroxy-1-butyl （4-hydroxy） benzoate （1）, and a known compound, fructigenines A （2）, were isolated from fungus Penicillium auratiogriseum derived from sponge Mycale plumose, by bioassay-guided fractionation. Their structures were established by spectroscopic and chemical methods. Both compounds *** cytotoxic activity against tsFT210 cells.

关键词： Penicillium auratiogriseum Mycale plumose aromatic ester alkaloid anti-tumoractivity

Torque Limit-based Inertial Control Method Based on Delayed Support for Primary Frequency Control of Wind Turbines

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 561-570页

作者： Wei gu Zaiyu Chen qun Li Minghui Yin qiang Li Yun Zou School of Automation Nanjing University of Science and TechnologyNanjing 210094China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing 211103China

To avoid the secondary frequency dip caused by the steep drop of the electrical power of wind turbines(WTs)at the end of frequency support stage,the torque limit-based iner-tial control(TLIC)method sets the power reference as a linear function of rotor speed,rather than the step form for the step-wise inertial ***,the compensation effect on the frequency nadir(FN)caused by the load surge is weakened as the TLIC power is no longer in the step ***,the maximum point of the frequency response component(FRC)contributed by TLIC occurs earlier than the minimum point of FRC corresponding to the load surge,so that the FN cannot be adequately ***,this paper first investigates the relation between the peak and nadir times of FRCs stimulated by the TLIC and load *** this basis,with the compensation principle of matching the peak and nadir times of FRCs,the improved TLIC method based on delayed support is ***,the effectiveness of the proposed method is validated via the experiments on the test bench of wind-integrated power system.

关键词： Wind turbine frequency response component torque limit inertial control delayed support

Description of martensitic transformation kinetics in Fe-C-X(X = Ni,Cr,Mn,Si) system by a modified model

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1026-1036页

作者： Xiyuan Geng Hongcan Chen Jingjing Wang Yu Zhang qun Luo qian Li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Ansteel Beijing Research Institute Co. LtdBeijing 102211China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be *** present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation *** describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic *** to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion *** relative error was approximately reduced by two-thirds compared with that of the Magee *** incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision.

关键词： Fe-C-X system martensitic transformation kinetics curve semi-empirical model nucleation activation energy

Ultrahigh performance passive radiative cooling by hybrid polar dielectric metasurface thermal emitters

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Advances 2024年第4期7卷 17-25页

作者： Yinan Zhang Yinggang Chen Tong Wang qian Zhu Min gu Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Real-world passive radiative cooling requires highly emissive,selective,and omnidirectional thermal emitters to maintain the radiative cooler at a certain temperature below the ambient temperature while maximizing the net cooling *** various selective thermal emitters have been demonstrated,it is still challenging to achieve these conditions sim-ultaneously because of the extreme difficulty in controlling thermal emission of photonic structures in *** we demonstrated hybrid polar dielectric metasurface thermal emitters with machine learning inverse design,en-abling a high emissivity of~0.92 within the atmospheric transparency window 8-13μm,a large spectral selectivity of~1.8 and a wide emission angle up to 80 degrees,*** selective and omnidirectional thermal emitter has led to a new record of temperature reduction as large as~15.4°C under strong solar irradiation of~800 W/m2,signific-antly surpassing the state-of-the-art *** designed structures also show great potential in tackling the urban heat island effect,with modelling results suggesting a large energy saving and deployment area *** research will make significant impact on passive radiative cooling,thermal energy photonics and tackling global climate change.

关键词： radiative cooling dielectric metasurfaces machine learning thermal emitters

Rethinking multi-spatial information for transferable adversarial attacks on speaker recognition systems

在线全文

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2024年第3期9卷 620-631页

作者： Junjian Zhang Hao Tan Le Wang Yaguan qian Zhaoquan gu guangzhou University GuangzhouChina Department of New Networks Peng Cheng LaboratoryShenzhenChina Harbin Institute of Technology(Shenzhen) ShenzhenChina Zhejiang University of Science and Technology HangzhouChina

Adversarial attacks have been posing significant security concerns to intelligent systems,such as speaker recognition systems(SRSs).Most attacks assume the neural networks in the systems are known beforehand,while black-box attacks are proposed without such information to meet practical *** black-box attacks improve trans-ferability by integrating multiple models or training on multiple datasets,but these methods are *** by the optimisation strategy with spatial information on the perturbed paths and samples,we propose a Dual Spatial Momentum Iterative Fast Gradient Sign Method(DS-MI-FGSM)to improve the transferability of black-box at-tacks against ***,DS-MI-FGSM only needs a single data and one model as the input;by extending to the data and model neighbouring spaces,it generates adver-sarial examples against the integrating *** reduce the risk of overfitting,DS-MI-FGSM also introduces gradient masking to improve *** authors conduct extensive experiments regarding the speaker recognition task,and the results demonstrate the effectiveness of their method,which can achieve up to 92%attack success rate on the victim model in black-box scenarios with only one known model.

关键词： speaker recognition spoofing attacks

Prediction of the thermal conductivity of Mg–Al–La alloys by CALPHAD method

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 129-137页

作者： Hongxia Li Wenjun Xu Yufei Zhang Shenglan Yang Lijun Zhang Bin Liu qun Luo qian Li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al *** accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high thermal ***,databases for predicting temperature-and composition-dependent thermal conductivities must be *** this study,Mg-Al-La alloys with different contents of Al2La,Al3La,and Al11La3phases and solid solubility of Al in the α-Mg phase were *** influence of the second phase(s) and Al solid solubility on thermal conductivity was *** results revealed a second phase transformation from Al_(2)La to Al_(3)La and further to Al_(11)La_(3)with the increasing Al content at a constant La *** degree of the negative effect of the second phase(s) on thermal diffusivity followed the sequence of Al2La>Al3La>Al_(11)La_(3).Compared with the second phase,an increase in the solid solubility of Al in α-Mg remarkably reduced the thermal *** the basis of the experimental data,a database of the reciprocal thermal diffusivity of the Mg-Al-La system was established by calculation of the phase diagram (CALPHAD)*** a standard error of±1.2 W/(m·K),the predicted results were in good agreement with the experimental *** established database can be used to design Mg-Al alloys with high thermal conductivity and provide valuable guidance for expanding their application prospects.

关键词： magnesium alloy thermal conductivity thermodynamic calculations materials computation

Partial aging can counter-intuitively couple with sulfidation to improve the reactive durability of zerovalent iron

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第2期18卷 1-11页

作者： Yiwei Liu Kaili gu Jinhua Zhang Jinxiang Li Jieshu qian Jinyou Shen Xiaohong guan Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200241China

Sulfated zero-valent iron(SZVI)has shown promising applications in wastewater ***,the rapid decline in the reactivity of SZVI with time limits its real *** mediate this problem,partial aging was proposed to improve the reactive durability of *** Cr(VI)as the target contaminant,we found that the aged ZVI(AZVI)gradually lost reactivity as aging time increased from 0.5 to 2 ***-intuitively,the partially aged SZVI(ASZVI)showed greater reactivity than SZVI when exposed to oxygenated water for a period ranging from 0.5 to 14 *** addition,the ASZVI with 0.5 d of aging time(ASZVI-0.5)not only maintained reactivity in successive runs but also increased the Cr(VI)removal capacity from 9.1 mg/g by SZVI to 19.1 mg/g by *** analysis further revealed that the electron transfer from the Fe0 core to the shell was mediated by the conductive FeS and FeS2 in the subshell of ***,the lepidocrocite and magnetite on the surface of ASZVI facilitated Cr(VI)adsorption and subsequent electron transfer for Cr(VI)***,the iron(hydr)oxide shell could retain the conductive FeS and FeS2 in the subshell,allowing ASZVI to reduce Cr(VI)efficiently and *** general,partial aging can enhance the reactive durability of ZVI when coupled with sulfidation and this synergistic effect will be beneficial to the application of SZVI-based technology for wastewater treatment.

关键词： Zerovalent iron Sulfidation Partial aging Interface reconstruction Electron transfer

Cytoplasmic FKBPs are involved in molting and metamorphosis through regulating the nuclear localization of EcR

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2024年第3期31卷 759-772页

作者： Xian Zhang Qiao-Ran Wang qian Wu Jun gu Li-Hua Huang guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology School of Life SciencesSouth China Normal UniversityGuangzhouChina guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouChina

Molting and metamorphosis are important physiological processes in insects that are tightly controlled by ecdysone receptor(EcR)through the 20-hydroxyecdysone(20E)signaling *** is a steroid nuclear receptor(SR).Several FK506-binding proteins(FKBPs)have been identified from the mammal SR complex,and are thought to be involved in the subcellular trafficking of ***,their roles in insects are poorly *** explore whether FKBPs are involved in insect molting or metamorphosis,we injected an FKBP inhibitor(FK506)into a lepidopteran insect,Spodoptera litura,and found that molting was inhibited in 61.11%of the larvae,and that the time for larvae to pupate was significantly extended.A total of 10 FKBP genes were identified from the genome of *** and were clustered into 2 distinct groups,according to their subcellular localization,with FKBP13 and FKBP14 belonging to the endoplasmic reticulum(ER)group and with the other members belonging to the cytoplasmic(Cy)*** the CyFKBPs were significantly upregulated in the prepupal or pupal stages,with the opposite being observed for the ER group ***506 completely blocked the transfer of EcR to the nucleus under 20E induction,and significantly downregulated the transcriptional expression of many 20E signaling genes.A similar phenomenon was observed after RNA interference of2 CyFKBPs(FKBP45 and FKBP12b),but not for *** together,our data indicate that the cytoplasmic FKBPs,especially FKBP45 and FKBP12b,mediate the nuclear localization of EcR,thereby regulating the 20E signaling and ultimately affecting molting and metamorphosis in insects.

关键词： EcR FKBP metamorphosis molting RNAi subcellular localization