检索结果-南通市图书馆

Study on the Protection of Polysaccharide and Flavone in Artemisia Annua L in Different Places to DNA with Fluorescence Probe

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Study on the Protection of Polysaccharide and Flavone in Art...

Proton beams from intense laser-solid interaction:effects of the target materials

第三十五届国际光谱会议

作者： H.R.Zhang j.e.chen C.j.Li Lab of Biochemical Analysis Xinzhou Teachers University Shanxi 034000 China

＜正＞The protection of polysaccharide and flavone compounds in14 kinds of Chinese herbs of Artemisia annua L at different growing places such as Hunan,Chongqing,Beijing *** DNA was comparatively *** fluorescence integration intensity of DNA,eB and extracts containing polysaccharide and flavone compounds from 14 kinds of artemisia annua L were determined with eB as a sensitive fluorescence probe.D can

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Matter and Radiation at extremes 2020年第6期5卷 42-47页

作者： Y.X.Geng D.Wu W.Yu Z.M.Sheng S.Fritzsche Q.Liao M.j.Wu X.H.Xu D.Y.Li W.j.Ma H.Y.Lu Y.Y.Zhao X.T.He j.e.chen C.Lin X.Q.Yan Key Laboratory of HeDP of the Ministry of education CAPTand State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute for Fusion Theory and Simulation Department of PhysicsZhejiang University310058 HangzhouChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics201800 ShanghaiChina SUPA Department of Physics University of StrathclydeGlasgow G40NGUnited Kingdom Key Laboratory for Laser Plasmas(Ministry of education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Helmholtz Institut-jena and Friedrich-Schiller-University D-07743 JenaGermany

We report systematic studies of laser-driven proton beams produced with micrometer-thick solid targets made of aluminum and plastic,*** effects of the target materials are found on the total charge,cutoff energy,and beam spot of protons in the experiments,and these are described well by two-dimensional particle-in-cell simulations incorporating intrinsic material *** is found that with a laser intensity of 8×10^(19) W/cm^(2),target normal sheath acceleration is the dominant mechanism for both types of *** a plastic target,the higher charge and cutoff energy of the protons are due to the greater energy coupling efficiencies from the intense laser beams,and the larger divergence angle of the protons is due to the deflection of hot electrons during transport in the *** also find that the energy loss of hot electrons in targets of different thickness has a significant effect on the proton cutoff *** consistent results obtained here further narrow the gap between simulations and experiments.

关键词： properties. intense solid

Optimization of Random Feature Method in the High-Precision Regime

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2024年第2期6卷 1490-1517页

作者： jingrun chen Weinan e Yifei Sun School of Mathematical Sciences and Suzhou Institute for Advanced Research Suzhou 215006JiangsuChina University of Science and Technology of China Hefei 230026AnhuiChina Center for Machine Learning Research and School of Mathematical Sciences Peking UniversityBeijing 100871China AI for Science Institute Beijing 100084China School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

Machine learning has been widely used for solving partial differential equations(PDes)in recent years,among which the random feature method(RFM)exhibits spectral accuracy and can compete with traditional solvers in terms of both accuracy and ***,the optimization problem in the RFM is more difficult to solve than those that arise in traditional *** the broader machine-learning research,which frequently targets tasks within the low-precision regime,our study focuses on the high-precision regime crucial for solving *** this work,we study this problem from the following aspects:(i)we analyze the coeffcient matrix that arises in the RFM by studying the distribution of singular values;(ii)we investigate whether the continuous training causes the overfitting issue;(ii)we test direct and iterative methods as well as randomized methods for solving the optimization *** on these results,we find that direct methods are superior to other methods if memory is not an issue,while iterative methods typically have low accuracy and can be improved by preconditioning to some extent.

关键词： Random feature method(RFM) Partial differential equation(PDe) Least-squares problem Direct method Iterative method

The effects of local variations in conditions on carbon storage and release in the continental mantle

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 22-36页

作者： Stephen F.Foley Chunfei chen Dorrit e.jacob School of Natural Sciences Macquarie University Research School of earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

Are hydrides under high-pressure-high-temperature superconductors?

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 9-12页

作者： j.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

journal of Magnesium and Alloys 2024年第3期12卷 954-965页

作者： Yimeng chen Manuel Legrée jean-Louis Bobet Alexander Kvit CAMeCA Instruments Inc MadisonWI 53711USA ICMCB Universitéde BordeauxPessacCEDEX 33608France NIAC&Materials Science Department University of WisconsinMadisonWI 53706USA

The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg *** current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STeM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal *** on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg ***-STeM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) *** addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding *** results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys.

关键词： Magnesium alloys Long-range ordering Atom probe tomography(APT) STeM HAADF Hydrolysis properties.

维普期刊数据库

Surface engineering with ionic polymers on membranes for boron removal

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang chenyi Fang j Paul chen Sui Zhang Department of Chemical and Biomolecular engineering National University of SingaporeSingapore 117576Singapore Department of Civil and environmental engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and environmental engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

OsbZIP53 Negatively Regulates Immunity Response by Involving in Reactive Oxygen Species and Salicylic Acid Metabolism in Rice

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rice science 2024年第2期31卷 190-202,I0022-I0028页

作者： WU Lijuan HAN Cong WANG Huimei He Yuchang LIN Hai WANG Lei chen chen e Zhiguo State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006China jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of education/jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Agricultural College of Yangzhou UniversityYangzhou 225009China

The basic region/leucine zipper(bZIP)transcription factors play important roles in plant development and responses to abiotic and biotic ***53 regulates resistance to Magnaporthe oryzae in rice by analyzing APIP5-RNAi transgenic *** further investigate the biological functions of OsbZIP53,we generated osbzip53 mutants using CRISPR/Cas9 editing and also constructed OsbZIP53 over-expression transgenic *** analysis of phenotypical,physiological,and transcriptional data showed that knocking-out OsbZIP53 not only improved disease resistance by inducing a hypersensitivity response in plants,but also regulated the immune response through the salicylic acid ***,disrupting OsbZIP53 increased H2O2 accumulation by promoting reactive oxygen species generation through up-regulation of several respiratory burst oxidase homologs(Osrboh genes)and weakened H2O2 degradation by directly targeting *** addition,the growth of osbzip53 mutants was seriously impaired,while OsbZIP53 over-expression lines displayed a similar phenotype to the wild type,suggesting that OsbZIP53 has a balancing effect on rice immune response and growth.

关键词： OsbZIP53 hypersensitive response reactive oxygen species metabolism rice immunity salicylic acid transcription factor

维普期刊数据库

WRKY11 up-regulated dirigent expression to enhance lignin/lignans accumulation in Lilium regale Wilson during response to Fusarium wilt

在线全文

学校读者我要写书评

暂无评论

journal of Integrative Agriculture 2024年第8期23卷 2703-2722页

作者： jie Deng Zi’e Wang Wenyun Li Xiaohua chen Diqiu Liu Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China

Lilium are highly economically valuable ornamental plants that are susceptible to Fusarium wilt caused by Fusarium *** regale Wilson,a wild lily native to China,is highly resistant to *** this study,a WRKY transcription factor,WRKY11,was isolated from ***,and its function during the interaction between *** and *** was *** ectopic expression of LrWRKY11 in tobacco increased the resistance to F oxysporum,moreover,the transcriptome sequencing and UHPLC-MS/MS analysis indicated that the methyl salicylate and methyl jasmonate levels rose in LrWRKY11 transgenic tobacco,meanwhile,the expression of lignin/lignans biosynthesis-related genes including a dirigent(DiR)was *** lignin/lignans contents in LrWRKY11-transgenic tobacco also significantly increased compared with the wild-type *** addition,the resistance of *** scales in which LrWRKY11 expression was silenced by RNAi evidently decreased,and additionally,the expression of lignin/lignans biosynthesis-related genes including LrDIR1 was significantly ***,LrDIR1 and its promoter(PLrDIR1)sequence containing the W-box element were isolated from *** interaction assay indicated that LrWRKY11 specifically bound to the W-box element in PLrDIR1 and activated LrDIR1 ***,β-glucuronidase activity in the transgenic tobacco co-expressing LrWRKY11/PLrDIR1-β-glucuronidase was higher than that in transgenic tobacco expressing PLrDIR1-β-glucuronidase ***,the ectopic expression of LrDIR1 in tobacco enhanced the resistance to *** and increased the lignin/lignans *** brief,this study revealed that LrWRKY11 positively regulated *** resistance to *** through interaction with salicylic acid/jasmonic acid signaling pathways and modulating LrDIR1 expression to accumulate lignin/lignans.

关键词： Lilium regale Fusarium oxysporum WRKY transcription factor dirigent

维普期刊数据库