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Breaking the efficiency limitations of dissipative Kerr solitons using nonlinear couplers

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 88-94页

作者： Ming li Xiao-Xiao xue Yan-Lei Zhang Xin-Biao Xu Chun-Hua Dong Guang-Can Guo Chang-ling Zou CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua University Beijing 100084China

Dissipative Kerr solitons(DKS) have long been suffering from poor power conversion efficiency when driven by continuous-wave lasers. By deriving the critical coupling condition of a multimode nonlinear optics system in a generalized theoretical framework,two efficiency limitations of the conventional pump method of DKS are revealed: the effective coupling rate is too small and is also power-dependent. A general approach is provided to resolve this challenge by introducing two types of nonlinear couplers to couple the soliton cavity and CW input through nonlinear processes. The collective coupler opens multiple coupling channels and the self-adaptive coupler builds a power-independent effective external coupling rate to the DKS for approaching the generalized critical coupling condition, which promises near-unity power conversion efficiencies. For instance, a conversion efficiency exceeding 90% is predicted for aluminum nitride microrings with a nonlinear coupler utilizing second-harmonic generation. The mechanism applies to various nonlinear processes, including Raman and Brillouin scattering, and thus paves the way for micro-solitons toward practical applications.

关键词： Kerr frequency comb conversion efficiency nonlinear coupler

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Spectra of Free Diquark in the Bethe-Salpeter Approach

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Communications in Theoretical Physics 2006年第6X期46卷 1031-1039页

作者： YU Yan-Ming KE Hong-Wei DING Yi-Bing GUO Xin-Heng JIN Hong-Ying li xue-Qian SHEN Peng- Nian WANG Guo-li Department of Physics Nankai University Tianjin 300071 China Department of Physics Graduate School of the Chinese Academy of Sciences Beijing 100049 China Institute of Low-Energy Nuclear Physics Beijing Normal University Beijing 100875 China Institute of Modern Physics Zhejiang University Hangzhou 310027 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100049 China Department of Physics Harbin Institute of Technology Harbin 150001 China

In this work, we employ the Bethe-Salpeter （B-S） equation to investigate the spectra of free diquarks and their B-S wave functions. We find that the B-S approach can be consistently applied to study the diqaurks with two heavy quarks or one heavy and one light quarks, but for two light-quark systems, the results are not reliable. There are a few free parameters in the whole scenario which can only be fixed phenomenologically. Thus, to determine them, one has to study baryons which are composed of quarks and diquarks.

关键词： Bethe-Salpeter equation diquark spectra

Studies on the Syntheses and Biological Activities of 3-Aryl-6-(1,1'-biphenyl-4-yl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines

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Chemical Research in Chinese Universities 2002年第4期18卷 393-396页

作者： YE Xiao-qin ZHANG li-xue ZHANG An-jiang CHEN Xian-xing ZHANG Zi-yi Department of Chemistry Wenzhou Teachers’CollegeWenzhou 325003P.R.China Chemistry Teaching and Research Section Wenzhou Medical CollegeWenzhou 325003P.R.China Department of Chemistry Lanzhou UniversityLanzhou 730000P.R.China

A series of novel 3-aryl-6-(1,1’-biphenyl-4-yl)-7H-1,2,4-triazolothiadiazines was synthesized by means of the reactions between 3-aryl-4-amino-5-mercapto-1,2,4-triazoles and 2-bromo-4’-phenylacetophenone. The structures of all the title compounds have been confirmed by virtue of elemental analysis, IR, 1H NMR, 13C NMR and mass spectra. The characteristics of 13C NMR peaks of the compounds were investigated. The plant growth regulating effects of those compounds were also determined.

关键词： H-1 2 4-Triazolothiadiazines Synthesis Biological activity

Broad-band phase retrieval method for transient radial shearing interference using chirp Z transform technique

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Chinese Physics B 2021年第8期30卷 398-406页

作者： Fang xue Ya-Xuan Duan Xiao-Yi Chen Ming li Suo-Chao Yuan Zheng-Shang Da The Advanced Optical Instrument Research Department Xi'an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi'an 710119China University of Chinese Academy of Sciences Beijing 100049China

The transient radial shearing interferometry technique based on fast Fourier transform(FFT)provides a means for the measurement of the wavefront phase of transient light ***,which factors affect the spatial bandwidth of the wavefront phase measurement of this technology and how to achieve high-precision measurement of the broad-band transient wavefront phase are problems that need to be studied *** this end,a theoretical model of phase-retrieved bandwidth of radial shearing interferometry is established in this *** influence of the spatial carrier frequency and the calculation window on phase-retrieved bandwidth is analyzed,and the optimal carrier frequency and calculation window are *** this basis,a broad-band transient radial shearing interference phase-retrieval method based on chirp Z transform(CZT)is proposed,and the corresponding algorithm is *** theoretical simulation,a known phase is used to generate the interferogram and it is retrieved by the traditional method and the proposed method *** residual wavefront RMS of the traditional method is 0.146λ,and it is 0.037λfor the proposed method,which manifests an improvement of accuracy by an order of *** the same time,different levels of signal-to-noise ratios(SNRs)from 50 dB to 10 dB of the interferogram are simulated,and the RMS of the residual wavefront is from 0.040λto 0.066λ.In terms of experiments,an experimental verification device based on a phase-only spatial light modulator is built,and the known phase on the modulator is retrieved from the actual *** RMS of the residual wavefront retrieved through FFT is 0.112λ,and it decreases to 0.035λthrough *** experimental results verify the effectiveness of the method proposed in this ***,the method can be used in other types of spatial carrier frequency interference,such as lateral shearing interference,rotational shearing interference,flipping shearing interference,and

关键词： radial shearing interference chirp Z transform(CZT) phase retrieval

The OsNAC23-Tre6P-SnRK1 a feed-forward loop regulates sugar homeostasis and grain yield in rice

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Molecular Plant 2022年第4期15卷 706-722页

作者： Zhiyong li Xiangjin Wei Xiaohong Tong Juan Zhao Xixi liu Huimei Wang liqun Tang Yazhou Shu Guanghao li Yifeng Wang Jiezheng Ying Guiai jiao Honghong Hu Peisong Hu Jian Zhang State Key Lab of Rice Biology China National Rice Research InstituteHangzhou 311400China College of life Science and Technology Huazhong Agricultural UniversityWuhan 430070China

Tre6P(trehalose-6-phosphate)mediates sensing of carbon availability to maintain sugar homeostasis in plants,which underpins crop yield and ***,how Tre6P responds to fluctuations in sugar levels and regulates the utilization of sugars for growth remains to be ***,we report that the sugar-inducible rice NAC transcription factor OsNAC23 directly represses the transcription of the Tre6P phosphatase gene TPP1 to simultaneously elevate Tre6P and repress trehalose levels,thus facilitating carbon partitioning from source to sink ***,OsNAC23 and Tre6P suppress the transcription and enzyme activity of SnRK1a,a low-carbon sensor and antagonist of OsNAC23,to prevent the SnRK1a-mediated phosphorylation and degradation of ***,OsNAC23,Tre6P,and SnRK1a form a feed-forward loop to sense sugar and maintain sugar homeostasis by transporting sugars to sink ***,plants over-expressing OsNAC23 exhibited an elevated photosynthetic rate,sugar transport,and sink organ size,which consistently increased rice yields by 13%–17%in three elite-variety backgrounds and two locations,suggesting that manipulation of OsNAC23 expression has great potential for rice ***,these findings enhance our understanding of Tre6P-mediated sugar signaling and homeostasis,and provide a new strategy for genetic improvement of rice and possibly also other crops.

关键词： Tre6P sugar homeostasis carbon partitioning NAC transcription factor grain yield rice

A facile and general approach for the synthesis of fluorescent silica nanoparticles doped with inert dyes

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Chinese Science Bulletin 2011年第31期56卷 3242-3246页

作者： MU xue WU Chuanliu LAI JinPing CHEN JianBin ZHENG JinSheng li Chong ZHAO YiBing Department of Chemistry and the Key Laboratory of Analytical Sciences of Xiamen University College of Chemistry and Chemical EngineeringXiamen University Xiamen 361005 China

A general and facile approach was developed for the synthesis of almost monodisperse fluorescent silica nanoparticles (NPs) doped with inert dyes, which are organic fluorophores that are strongly fluorescent but are hydrophobic or lack a covalent binding group. The prepared NPs were mesoporous and the dye molecules were encapsulated in the pores via hydrophobic interaction with the CTAB template. The NPs were stable and highly fluorescent in aqueous solution, and have potential applications in bioanalysis and fluorescence encoding.

关键词：有机荧光染料纳米颗粒惰性合成硅胶轻便纳米粒子疏水相互作用

Development of Integrated Computational Materials Engineering(ICME)Model for Mg Alloy Design and Process Optimization

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Journal of Beijing Institute of Technology 2023年第4期32卷 422-442页

作者： Hui Su Zhifei Yan Yingchun Tian Chengpeng xue Shuo Wang Guangyuan Tian Xinghai Yang Quan li xuelong Wu Zhongyao li Junsheng Wang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China China North Industries Group No.52 Research InstituteBaotouInner Mongolia 014030China

Integrated computational materials engineering(ICME)has emerged to be one of the most powerful materials genome engineering(MGE)approaches in designing new materials and manufacturing processes in recent *** has successfully deployed many new products for the electronic,automotive,and aerospace *** paper reviews the current status of research on first principles in the design of high-strength Mg alloys,discusses the application of crystal plasticity finite element models to the microscale slip,twinning,microstructure morphology,texture evolution,and macroscopic forming of Mg alloys,and introduces the research progress of crystal plasticity finite element models and phase field models,meta cellular automata models and first principles coupled models respectively,around the need for multi-scale coupled simulations of Mg *** key technology obstacles of integrating the first principles,crystal plasticity finite element,and microstructure models for Mg alloys have been *** paper can provide a reference for the design of new Mg alloy compositions and the development of high-performance Mg alloys.

关键词： first-principles crystal plasticity finite elements microstructure Mg alloys

Epigenetics in neonatal diseases

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Chinese Medical Journal 2010年第20期123卷 2948-2954页

作者： XU xue-feng DU li-zhong Children's Hospital Zhejiang University School of Medicine Hangzhou Zhejiang 310003 China

Objective To review the role of epigenetic regulation in neonatal diseases and better understand Barker＇s ＂fetal origins of adult disease hypothesis＂.Data sources The data cited in this review were mainly obtained from the articles published in Medline/PubMed between January 1953 and December *** selection Articles associated with epigenetics and neonatal diseases were *** There is a wealth of epidemiological evidence that lower birth weight is strongly correlated with an increased risk of adult diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular disease. This phenomenon of fetal origins of adult disease is strongly associated with fetal insults to epigenetic modifications of genes. A potential role of epigenetic modifications in congenital disorders, transient neonatal diabetes mellitus （TNDM）, intrauterine growth retardation （IUGR）, and persistent pulmonary hypertension of the newborn （PPHN） have been *** Acknowledgment of the role of these epigenetic modifications in neonatal diseases would be conducive to better understanding the pathogenesis of these diseases, and provide new insight for improved treatment and prevention of later adult diseases.

关键词： epigenetics congenital disorders transient neonatal diabetes mellitus intrauterine growth retardation persistent pulmonary hypertension newborn

Risk factors of gastroparesis syndrome after abdominal nongastroduodenal operation and its prevention

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Asian Pacific Journal of Tropical Medicine 2013年第6期6卷 497-499页

作者： Dong-Dong Yang Kun He xue-liang Wu li-Kun Yang Shuang-Fa Nie First Affiliated Hospital Hebei North University

Objective:To investigate risk factors of gastroparesis syndrome(PGS) after abdominal nongastroduodenal operation and its ***:Clinical data of 22 patients with PGS after abdominal non-gastroduodenal operation was analyzed retrospectively,and compared with the patients of non-PGS after abdominal non-gastroduodenal operation during the same *** possible influencing factors of PCS were analyzed by single factor analysis and logistic regression ***:All t3 selected factors related with PGS,including age,disease category (benign and malignant),operation time,intraoperative blood loss,postoperative analgesic pump, postoperative enteral nutrition time,postoperative parenteral nutrition time,perioperative blood glucose level,perioperative nutrition status(anaemia or lower proleinemia),pylorus obstruction before surgery,intra-abdominal infection after surgery,and spiritual factor were related with *** statistical analysis showed that the difference was statistical significant(P0.05);non-conditional multivariate analysis showed that malignant tumor,perioperative nutrition status,pylorus obstruction,operation time,blood loss, intra-abdominal infection after surgery,and mental factor were significant related with PGS as dependent variable and related risk factors in single factor analysis as independent variables (P lignant tumor,poor nutrition status,pylorus obstruction before surgery,longer operation—time,more blood loss,intra-abdominal infection after surgery,and mental factor are major risk factors of PGS.

关键词： Abdominal non-gastroduodenal operation Postsurgical gastroparesis syndrome Risk factors Comparative analysis