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Synthesis and biological evaluation of novel steroid-linked nitrogen mustards

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Chinese Chemical Letters 2009年第6期20卷 680-683页

作者： Hua Bing Zhang Ji jun Xue Xiao long zhao De Gang Liu Ying Li State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 PR China

Two novel steroid-linked nitrogen mustard conjugates la and lb were synthesized by using estrogenic acid 4 coupled with aniline mustard 8 and phenol mustard 13 in an esterification or amidation procedure. Preliminary cytotoxic screening on cancer cell lines in vitro showed that, the steroid-ester linked nitrogen mustard conjugate la exhibited obvious increasing of activities.

关键词： Steroid Nitrogen mustards Synthesis Biological activity

Transfer of quantum entangled states between superconducting qubits and microwave field qubits

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Frontiers of physics 2022年第6期17卷 163-174页

作者： Tong Liu Bao-Qing Guo Yan-Hui Zhou jun-long zhao Yu-Liang Fang Qi-Cheng Wu Chui-Ping Yang Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China Department of Physics Hangzhou Normal UniversityHangzhou 311121China

Transferring entangled states between matter qubits and microwave-field(or optical-field)qubits is of fundamental interest in quantum mechanics and necessary in hybrid quantum information processing and quantum *** here propose a way for transferring entangled states between superconducting qubits(matter qubits)and microwave-field *** proposal is realized by a system consisting of multiple superconducting qutrits and microwave ***,“qutrit”refers to a three-level quantum system with the two lowest levels encoding a qubit while the third level acting as an auxiliary *** contrast,the microwave-field qubits are encoded with coherent states of microwave *** the third energy level of each qutrit is not populated during the operation,decoherence from the higher energy levels is greatly *** entangled states can be deterministically transferred because measurement on the states is not *** operation time is independent of the number of superconducting qubits or microwave-field *** addition,the architecture of the circuit system is quite simple because only a coupler qutrit and an auxiliary cavity are *** an example,our numerical simulations show that high-fidelity transfer of entangled states from two superconducting qubits to two microwave-field qubits is feasible with present circuit QED *** proposal is quite general and can be extended to transfer entangled states between other matter qubits(e.g.,atoms,quantum dots,and NV centers)and microwave-or optical-field qubits encoded with coherent states.

关键词： tranferring entangled states superconducting qubits microwave field qubits coherent states circuit QED

Automatic modeling algorithm of stochastic error for inertial sensors

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Control Theory and Technology 2024年第1期22卷 81-91页

作者： Luodi zhao long zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Digital Navigation Center Beihang UniversityBeijing100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing100191China

This paper proposes an automatic algorithm to determine the properties of stochastic processes and their parameters for inertial error. The proposed approach is based on a recently developed method called the generalized method of wavelet moments (GMWM), whose estimator was proven to be consistent and asymptotically normally distributed. This algorithm is suitable mainly (but not only) for the combination of several stochastic processes, where the model identification and parameter estimation are quite difficult for the traditional methods, such as the Allan variance and the power spectral density analysis. This algorithm further explores the complete stochastic error models and the candidate model ranking criterion to realize automatic model identification and determination. The best model is selected by making the trade-off between the model accuracy and the model complexity. The validation of this approach is verified by practical examples of model selection for MEMS-IMUs (micro-electro-mechanical system inertial measurement units) in varying dynamic conditions.

关键词： GMWM Stochastic process Inertial sensor Sensor calibration Error model Allan variance

Micro-trichome as a class I homeodomain-leucine zipper gene regulates multicellular trichome development in Cucumis sativus

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维普期刊数据库

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Journal of Integrative Plant Biology 2015年第11期57卷 925-935页

作者： jun-long zhao jun-Song Pan Yuan Guan Wei-Wei Zhang Bei-Bei Bie Yun-Li Wang Huan-Le He Hong-Li Lian Run Cai School of Agriculture and Biology Shanghai Jiao Tong University

Plant trichomes serve as a highly suitable model for investigating cell differentiation at the single-cell level. The regulatory genes involved in unicellular trichome develop- ment in Arabidopsis thaliana have been intensively studied, but genes regulating multicellular trichome development in plants remain unclear. Here, we characterized Cucumis sativus （cucumber） trichomes as representative multicellular and unbranched structures, and identified Micro-trichome （Mict）, using map-based cloning in an F2 segregating population of 7,936 individuals generated from a spontaneous mict mutant. In mitt plants, trichomes in both leaves and fruits, are small, poorly developed, and denser than in the wild type. Sequence analysis revealed that a 2,649-bp genomic deletion, spanning the first and second exons, occurred in a plant-specific class I homeodomain-leucine zipper gene. Tissue-specific expression analysis indicated that Mict is strongly expressed in the trichome cells. Transcriptome profiling identified potential targets of Mict including putative homologs of genes known in other systems to regulate trichome development, meristem determinacy, and hormone responsiveness. Phylo- genic analysis charted the relationships among putative homologs in angiosperms. Our paper represents initial steps toward understanding the development of multicellular trichomes.

关键词： Cucumis sativus HD-Zip gene map-based cloning multicellular trichome transcriptome

Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 135-145页

作者： Su Shuo long jun Duan Qinghua Zhou Han zhao Yi SINOPEC Research Institute of Petroleum Processing Co.Ltd. Beijing 100083

To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established *** molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular *** results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen *** on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur *** results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions.

关键词： lubricating oil antioxidant molecular mechanism molecular design antioxidant performance

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： Lan-Kun Li Ming-Yi Dong Ze Gao Liang-Cheng-long Jin Shu-jun zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution

Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： Ke Yu Wei-Min Kong Zhen zhao Ai-jun Duan Lian Kong Xi-long Wang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective ***-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic *** as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS *** average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic *** cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active *** embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS *** improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long zhao Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

Extension of Noether's theorem in PT-symmetry systems and its experimental demonstration in an optical setup

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 13-27页

作者： Qi-Cheng Wu jun-long zhao Yu-Liang Fang Yu Zhang Dong-Xu Chen Chui-Ping Yang Franco Nori Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Physics Nanjing UniversityNanjing 210093China Department of Physics Hangzhou Normal UniversityHangzhou 311121China Theoretical Quantum Physics Laboratory RIKENWako-shiSaitama 351-0198Japan RIKEN Center for Quantum Computing RIKENWako-shiSaitama 351-0198Japan Physics Department The University of MichiganAnn Arbor 48109-1040USA

Noether’s theorem is one of the fundamental laws in physics,relating the symmetry of a physical system to its constant of motion and conservation *** the other hand,there exist a variety of non-Hermitian parity-time(PT)-symmetric systems,which exhibit novel quantum properties and have attracted increasing *** this work,we extend Noether’s theorem to a class of significant PT-symmetry systems for which the eigenvalues of the PT-symmetry Hamiltonian HPTchange from purely real numbers to purely imaginary numbers,and introduce a generalized expectation value of an operator based on biorthogonal quantum *** find that the generalized expectation value of a time-independent operator is a constant of motion when the operator presents a standard symmetry in the PT-symmetry unbroken regime,or a chiral symmetry in the PT-symmetry broken *** addition,we experimentally investigate the extended Noether’s theorem in PT-symmetry single-qubit and two-qubit systems using an optical *** experiment demonstrates the existence of the constant of motion and reveals how this constant of motion can be used to judge whether the PT-symmetry of a system is ***,a novel phenomenon of masking quantum information is first observed in a PT-symmetry two-qubit *** study not only contributes to full understanding of the relation between symmetry and conservation law in PT-symmetry physics,but also has potential applications in quantum information theory and quantum communication protocols.

关键词： Noether’s theorem PT-symmetry systems chiral symmetry optical setup