检索结果-南通市图书馆

A fast space-time-domain Gaussian beam migration approach using the dominant frequency approximation

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2022年第4期19卷 1555-1565页

作者： Dong-lin Zhang Jian-Ping Huang Ji-Dong yang Zhen-Chun li Su-Bin Zhuang qing-yang li School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Pilot National Laboratory for Marine Science and Technology QingdaoShandong 266580China Geophysical Exploration Research Institute of Zhongyuan Oilfield Company PuyangHenan 457001China

The Gaussian beam migration(GBM) is a steady imaging approach, which has high accuracy and efficiency. Its implementation mainly includes the traditional frequency domain and the recent popular space-time domain. Firstly, we use the upward ray tracing strategy to get the backward wavefields. Then,we use the dominant frequency of the seismic data to simplify the imaginary traveltime calculation of the wavefields, which can cut down the Fourier transform number compared with the traditional GBM in the space-time domain. In addition, we choose an optimized parameter for the take-off angle increment of the up-going and down-going rays. These optimizations help us get an efficient space-time-domain acoustic GBM approach. Typical four examples show that the proposed method can significantly improve the computational efficiency up to one or even two orders of magnitude in different models with different model parameters and produce good imaging results with comparable accuracy and resolution with the traditional GBM in the space-time domain.

关键词： Gaussian beam Space-time-domain Fast Dominant frequency approximation

MULTISTEP DISCRETIZATION OF INDEX 3 DAES

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2000年第3期18卷 325-336页

作者： yang Cao qing-yang li (Department of Mathematics, Tsinghua University, Beijing 100084, China) 清华大学北京 100084

Studies the different types of multistep discretization of index 3 differential-algebraic equations in Hessenberg form. Existense, uniqueness and influence of perturbations; Local convergence of multistep discretizati... 详细信息

关键词： multistep methods Adams method BDF DAEs Index 3

Anthocyanin Accumulation Mediated by Blue light and Cytokinin in Arabidopsis Seedlings

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2006年第4期48卷 420-425页

作者： Da-qing Chen Zhi-yang li Rui-Chi Pan Xiao-Jing Wang College of life Sciences South China Normal University Guangdong Key Laboratory of Biotechnology for Plant Development Guangzhou 510631 China

It has been reported that pigmentation In plants Is stimulated by light and cytoklnln （CTK）; however, the signaling pathways and the relationship between light and CTK Involved In the regulation of anthocyanln accumulation remain to be elucidated. We Investigated （i） the role of blue light （BL） and CTK In anthocyanln accumulation ; and （ii） the relationship between BL and CTK In wild type （WT） and by4 mutants of Arabidopsis thaiiana. Two-d-old seedlings grown on medium with or without klnetln （KT） or zeatln （ZT） In darkness were Irradiated using BL at different fluence rates for 3 d before the anthocyanln content was determined using a spectrophotometrlc method. Anthocyanln accumulation was strongly Induced by BL In WT seedlings but not In hy4 seedlings, which demonstrated that CRY1 Is the main photoreceptor for BL. Both KT and ZT enhanced the response of the WT seedlings to BL In a dose-dependent manner, whereas they were not sufficient to promote anthocyanln eccumulatlon In darkness. In addition, data from experiments using the hy4 mutant showed that the CTK effect of BL was also CRYl-dependent. The results from experiments with three different treatment programs showed that the relationship between BL and KT In anthocyanln accumulation of Arabidopsis seedlings seems neither muItlpllcatlve nor additive coactlon, but rather Interaction. BL Is necessary for anthocyanln accumulation, and KT might be Involved In the BL signaling pathway.

关键词： anthocyanin Arabidopsis blue light cytokinin by4 mutant.

Identification and Expression Analysis of the Phosphoenolpyruvate Carboxylase Gene Family in Peanut (Arachis hypogaea L.)

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

Agricultural Sciences in China 2010年第4期9卷 477-487页

作者： YU Shan-lin PAN li-juan yang qing-li CHEN Ming-na ZHANG Hong-sheng State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing 210095 P.R.China Shandong Peanut Research Institute Qingdao 266100 P.R.China

Phosphoenolpyruvate carboxylase （PEPC） is widely distributed in plants and bacteria, and catalyzes the carboxylation of phosphoenolpyruvate to form oxaloacetate and inorganic phosphate. To investigate the molecular mechanisms of the regulation and control of peanut oil, with the degenerated primers and RACE-PCR approach, five PEPC genes were cloned from peanut, and designated as AhPEPC1, AhPEPC2, AhPEPC3, AhPEPC4, and AhPEPC5, respectively. The structure and phylogenetic analysis of PEPC protein indicated that AhPEPC1-4 genes encoded a typical plant-type PEPC-enzyme, and AhPEPC5 a bacterial-type. By real-time quantitative RT-PCR approach the expression pattern of each gene was detected in various tissues of normal and high oil-content peanut varieties. It was found that there was a lower expression level of AhPEPCs genes except for the AhPEPC2 in high-oil peanut than normal-oil peanut line. The results provide some fundamental information for the further investigation of plant PEPC proteins and their role in regulation of oil-content in peanut seeds.

关键词： peanut phosphoenolpyruvate carboxylase gene cloning expression pattern regulation of oil-content

Functional Analysis of the Phosphoenolpyruvate Carboxylase on the lipid Accumulation of Peanut(Arachis hypogaea L.) Seeds

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第1期12卷 36-44页

作者： PAN li-juan yang qing-li CHI Xiao-yuan CHEN Ming-na yang Zhen CHEN Na WANG Tong WANG Mian HE Ya-nan YU Shan-lin Shandong Peanut Research Institute

Phosphoenolpyruvate carboxylase（PEPC;EC 4.***.1.31） catalyses phosphoenolpyruvate（PEP） to yield oxaloacetate,which is involved in protein *** kinase（PK;EC 2.***.1.40） catalyzes PEP to yield pyruvate,which is involved in fatty acid *** this study,five PEPC genes（AhPEPC1,AhPEPC2,AhPEPC3,AhPEPC4,and AhPEPC5） from peanut have been *** a quantitative real-time RT-PCR approach,the expression pattern of each gene was monitored during the seed development of four peanut varieties（E11,Hebeigaoyou,Naihan 1,and Huayu 26）.It was found that these five genes shared similar expression behaviors over the developmental stages of E11 with high expression levels at 30 and 40 d after pegging（DAP）;whereas these five genes showed irregular expression patterns during the seed development of *** Naihan 1 and Huayu 26,the expression levels of the five genes remained relatively high in the first *** PEPC activity was monitored during the seed development of four peanut varieties and seed oil content was also characterized during whole period of seed *** PEPC activity followed the oil accumulation pattern during the early stages of development but they showed a significantly negative correlation *** results suggested that PEPC may play an important role in lipid accumulation during the seed development of four peanut varieties tested.

关键词： peanut(Arachis hypogaea L.) phosphoenolpyruvate carboxylase PEPC activity lipid accumulation

Synthesis and characterization of poly[(4-vinylphenyl)dimethyl-silane]-b-polybutadiene-b-poly[(4-vinylphenyl)dimethylsilane](PVPDMS-b-PBd-b-PVPDMS)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第11期22卷 1371-1374页

作者： Hong Wei Ma Bai Wang Chun qing Zhang yang li Yan Ming Hu Yu Rong Wang liaoning Key Laboratory of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian Liaoning 116024 China

The novel functionalized triblock copolymers,poly[（4-vinylphenyl）dimethylsilane]-b-polybutadiene-b-poly[（4-vinylphenyl）-dimethylsilane] （PVPDMS-b-PBd-b-PVPDMS）,were synthesized by anionic polymerization method using high vacuum technique. The hydrocarbon-soluble dilithium initiator synthesized from l,3-di[l-（methylphenyl）ethenyl]benzene（MPEB） was used to synthesize polybutadiene（PBd） precursors and the triblock copolymers in the presence of *** precursors and copolymers were characterized by size exclusion chromatography（SEC）,~1HNMR and DSC techniques.

关键词： Anionic polymerization Functionalized triblock copolymers High vacuum technique

Metallogenic model of sandstone-hosted copper deposits:a case study from the Paleogene in Jiashi area,northwestern China

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2025年第01期14卷 105-125页

作者： Long-qing Shi Xing-Yue Qu Carlos Zavala yang li College of Earth Science and Engineering Shandong University of Science and Technology Geology Department Universidad Nacional del Sur Geología de Cuencas Sedimentarias (GCS) Argentina Institute of Energy Peking University Ordos Research Institute of Energy Peking University Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology

Sandstone-hosted copper deposits,a type of Sediment-Hosted Stratiform Copper (SSC) deposits,are widely distributed *** economically viable deposits of SSC are relatively scarce,they account for approximately 30%of the world's total discovered copper ***,there is still a lack of comprehensive and in-depth research into the depositional and metallogenic models of these *** Jiashi area of the Tarim Basin in northwestern China,known for its economically significant Paleogene SSC deposit,lacks in-depth studies on metallogenic *** address this,field profile observations were conducted to analyze the sedimentary evolution,sequence stratigraphy,and tectonism of the Paleogene strata in the Jiashi *** with elemental geochemical analysis of samples,the provenance of sediment,and the source of metallogenic materials,a robust metallogenic model was *** results reveal the influence of provenance for the origin of Paleogene copper-rich *** evolution played a crucial role in controlling the distribution of copper and sulfur elements,as well as the spatial arrangement of metallogenic ***,nappe movement potentially generated faults,allowing upward movement of basin fluids,which played a crucial role in the formation of copper deposits within sandstone-hosted ***,this study offers a comprehensive analysis of the metallogenic processes involved in sandstone-hosted copper deposits,thereby contributing significant insights to the broader research on SSC deposits worldwide.

关键词： Tarim Basin Paleogene Sandstone-hosted copper deposits Metallogenic material source Metallogenic model

Successful treatment of adalimumab-resistant palmoplantar pustulosis with secukinumab:a case report

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Medical Journal 2020年第24期133卷 3013-3014页

作者： qing-yang li Gang Wang Department of Dermatology Xijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China

To the Editor:Palmoplantar pustulosis(PPP)is a chronic recalcitrant *** biologics have been used to successfully treat plaque psoriasis,but their use to treat PPP is *** their promising effects,biologics such as tumor necrosis factor-α(TNF-α)inhibitors may aggravate or induce ***,we report a patient with PPP refractory to the TNF-αinhibitor adalimumab,but successfully treated with the interleukin-17A(IL-17A)inhibitor secukinumab.

关键词： spite treatment PPP

Effect of pseudo-random number on the security of quantum key distribution protocol

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2025年第2期34卷 41-46页

作者： Xiao-liang yang Yu-qing li Hong-Wei li Henan Key Laboratory of Quantum Information and Cryptography SSF IEUZhengzhou 450000China

In the process of quantum key distribution(QKD), the communicating parties need to randomly determine quantum states and measurement bases. To ensure the security of key distribution, we aim to use true random sequences generated by true random number generators as the source of randomness. In practical systems, due to the difficulty of obtaining true random numbers, pseudo-random number generators are used instead. Although the random numbers generated by pseudorandom number generators are statistically random, meeting the requirements of uniform distribution and independence,they rely on an initial seed to generate corresponding pseudo-random sequences. Attackers may predict future elements from the initial elements of the random sequence, posing a security risk to quantum key distribution. This paper analyzes the problems existing in current pseudo-random number generators and proposes corresponding attack methods and applicable scenarios based on the vulnerabilities in the pseudo-random sequence generation process. Under certain conditions, it is possible to obtain the keys of the communicating parties with very low error rates, thus effectively attacking the quantum key system. This paper presents new requirements for the use of random numbers in quantum key systems, which can effectively guide the security evaluation of quantum key distribution protocols.

关键词： quantum key distribution pseudo-random security