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Polymers with tertiary amine groups for drug delivery and bioimaging

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Science China Chemistry 2016年第8期59卷 991-1002页

作者： yu-Juan gao Zeng-Ying Qiao Hao Wang CAS Center for Excellence in Nanoscience CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Techr ology Beijing 100190 China

Over the past decade, biopolymers have gained great interests especially in biomedicine due to their physical properties and/or chemical structures changes in response to external stimuli in a certain time fiarne or at a specific location. Among them, poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups have been extensively studied and exhibit pH sensitive properties due to the protonation of tertiary amine groups. The pH values in normal organs, tissues, and subcellular compartments are always different from those in pathological tissues. These interesting properties allow their applications in a variety of fields ranging from diagnosis and therapeutics of diseases. Here, we review the recent progress of poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups and their applications in drug delivery and bioimaging.

关键词： biopolymers tertiary amine groups pH-responsive drug delivery bioimaging

Preliminary physics study of the Lead–Bismuth Eutectic spallation target for China Initiative Accelerator-Driven System

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Nuclear Science and Techniques 2016年第5期27卷 215-224页

作者： Lu Zhang Yong-Wei Yang yu-Cui gao Department of Spallation Target Institute of Modern PhysicsChinese Academy of Sciences509 Nanchang RoadLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The Lead-Bismuth Eutectic(LBE) spallation target has been considered as one of the two alternatives for the spallation target for China Initiative Accelerator-Driven *** paper reports the preliminary study on physical feasibility of a U-type LBE target with *** simulation results based on Monte Carlo transport code MCNPX indicate that the spallation neutron yield is about 2.5 per *** maximum spallation neutron flux is observed at about 3 cm below the lowest part of the *** the LBE target is coupled with the reactor,the reactor neutrons from the fission reaction increased the neutron field *** energy deposition of highenergy protons is the main heat source;the spallation neutrons and reactor neutrons contribute only a small *** maximum energy deposition in the LBE is about 590 W/cm^3 and that in the target window is about319 W/cm^*** estimate the lifetime of the target window,we have calculated the radiation *** maximum displacement production rate in the target window is about10 dpa/*** hydrogen and helium production rates generated during normal operation were also *** analyzing the residual nucleus in the target during the steady operation,we estimated the accumulated quantities of the extreme radioactivity toxicant ^(210)Po in the LBE target *** results would be helpful for the evaluation of the target behavior and will be beneficial to the optimization of the target design work of the experimental facilities.

关键词：加速器驱动系统散裂靶学习主动性物理中国共晶中子通量铋

Decomposition Method of Complex Optimization Model Based on Global Sensitivity Analysis

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 722-729页

作者： QIU Qingying LI Bing FENG Peien gao yu State Key Laboratory of CAD&CG Zhejiang University

The current research of the decomposition methods of complex optimization model is mostly based on the principle of disciplines, problems or components. However, numerous coupling variables will appear among the sub-models decomposed, thereby make the efficiency of decomposed optimization low and the effect poor. Though some collaborative optimization methods are proposed to process the coupling variables, there lacks the original strategy planning to reduce the coupling degree among the decomposed sub-models when we start decomposing a complex optimization model. Therefore, this paper proposes a decomposition method based on the global sensitivity information. In this method, the complex optimization model is decomposed based on the principle of minimizing the sensitivity sum between the design functions and design variables among different sub-models. The design functions and design variables, which are sensitive to each other, will be assigned to the same sub-models as much as possible to reduce the impacts to other sub-models caused by the changing of coupling variables in one sub-model. Two different collaborative optimization models of a gear reducer are built up separately in the multidisciplinary design optimization software iSIGHT, the optimized results turned out that the decomposition method proposed in this paper has less analysis times and increases the computational efficiency by 29.6%. This new decomposition method is also successfully applied in the complex optimization problem of hydraulic excavator working devices, which shows the proposed research can reduce the mutual coupling degree between sub-models. This research proposes a decomposition method based on the global sensitivity information, which makes the linkages least among sub-models after decomposition, and provides reference for decomposing complex optimization models and has practical engineering significance.

关键词： multidisciplinary design optimization collaborative optimization sensitivity analysis coupled factorization iSIGHT

Preparation and verification of mixed high-energy neutron crosssection library for ADS

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Nuclear Science and Techniques 2018年第10期29卷 163-170页

作者： Ze-Long Zhao Yong-Wei Yang Hai-Yan Meng Qing-yu gao yu-Cui gao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

An accelerator-driven subcritical system(ADS)is driven by an external spallation neutron source, which is generated from a heavy metal spallation target to maintain stable operation of the subcritical core, where the energy of the spallation neutrons can reach several hundred megaelectron volts. However, the upper neutron energy limit of nuclear cross-section databases, which are widely used in critical reactor physics calculations, is generally 20 *** is not suitable for simulating the transport of highenergy spallation neutrons in the ADS. We combine the Japanese JENDL-4.0/HE high-energy evaluation database and the ADS-HE and ADS 2.0 libraries from the International Atomic Energy Agency and process all the data files for nuclides with energies greater than 20 MeV. We use the continuous pointwise cross-section program NJOY2016 to generate the ACE-formatted cross-section data library IMPC-ADS at multiple temperature points. Using the IMPC-ADS library, we calculate 10 critical benchmarks of the International Criticality Safety Benchmark Evaluation Project manual, the 14-MeV fixed-source problem of the Godiva sphere, and the neutron flux of the ADS subcritical core by MCNPX. To verify the correctness of the IMPCADS, the results were compared with those calculated using the ENDF/B-VII.0 library. The results showed thatthe IMPC-ADS is reliable in effective multiplication factor and neutron flux calculations, and it can be applied to physical analysis of the ADS subcritical reactor core.

关键词： Accelerator-driven subcritical system IMPCADS MCNPX NJOY2016 Neutron cross section

Physical studies of minor actinide transmutation in the accelerator-driven subcritical system

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Nuclear Science and Techniques 2019年第6期30卷 35-43页

作者： Hai-Yan Meng Yong-Wei Yang Ze-Long Zhao Qing-yu gao yu-Cui gao Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China School of Nuclear Science and Technology University of Chinese Academy of Sciences Beijing 100049 China

The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal *** is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.

关键词： ADS COUPLE3.0 MA Transmutation Subcritical reactor

Palladium nanoparticles supported on amine-functionalized glass fiber mat for fixed-bed reactors on the effective removal of hexavalent chromium by catalytic reduction

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Journal of Materials Science & Technology 2018年第6期34卷 961-968页

作者： yu gao Wuzhu Sun Weiyi Yang Qi Li Environment Functional Materials Division Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Materials China Academy of Engineering Physics Mianyang 621900 China School of Materials Science and Engineering Shandong University of Technology Zibo 255000 China

Palladium nanoparticles were deposited on the amine-grafted glass fiber mat （GFM-NH2） catalyst support by a conventional impregnation process followed by the borohydride reduction in aqueous solution at room temperature to create the designed Pd/GFM-NH2 catalyst. By the use of large size glass fiber mat without nano/mesopores as the catalyst support, the internal mass transfer limitations due to the existence of nano/mesopores on the catalyst support were eliminated and the Pd/GFM-NH2 catalyst could be easily separated from treated water due to the large size of the catalyst support. Batch experiments demonstrate its good catalytic reduction performance of Cr（VI） with formic acid as the reducing agent. It also demonstrated an efficient Cr（VI） removal and stability in a lab-prepared, packed fixed-bed tube reactor for the continuous treatment of Cr（VI）-containing water. Thus, it has a good potential for the catalytic reduction of Cr（VI） in the water treatment practice.

关键词： Palladium nanoparticle Amine-functionalized glass fiber mat Fixed-bed reactor Hexavalent chromium Catalytic reduction

Cloning of PsMYB62 and analysis of cadmium resistant in Potentilla sericea

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BIOCELL 2023年第7期47卷 1571-1582页

作者： ZHENGHONG FENG BING gao yu gao JIANHUI WU College of Landscape Architecture Northeast Forestry UniversityHarbin150040China Research Center for Economic Plant Pests Heilongjiang Forest Protection InstituteHarbin150040China

Potentilla sericea is a heavy metal hyperaccumulator landscaping *** transcription factors play an important role in regulating plant stress response to ***,there are few studies on MYB transcription factors in stress tolerance in Potentilla *** this study,the PsMYB62 gene was successfully cloned from Potentilla ***:Bioinformatic analysis and real-time quantitative PCR(qPCR)methods were used to evaluate this *** transgenic *** were obtained by flower dipping and the gene function was identified by determining physiological indicators under cadmium ***:The open reading frame of PsMYB62 is 942 bp,which encodes 313 amino acids(aa)and belongs to the R2R3 MYB transcription *** plant overexpression vector PBI121-PsMYB62-GFP was constructed and successfully transferred into *** relative expression level of PsMYB62 was significantly increased by CdCl_(2),NaCl,ABA,and mannitol *** germination rate of transgenic seeds was higher than those of wild type(WT)and empty vector(EV)under different concentrations of cadmium *** treatment with 100μmol·L^(−1)of CdCl_(2)·2.5H_(2)O,the activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)in the transgenic plants were significantly higher than those in the WT and *** contents of H_(2)O_(2),O_(2)·−and malondialdehyde(MDA)in transgenic lines were increased,but lower than those in WT and *** expression levels of AtGSH,AtPCS,and AtNAS4 that were related to the regulation of cadmium were increased,but the expression levels of transgenic lines were higher than those of WT and ***:The above results showed that PsMYB62 could be induced by cadmium and could improve the cadmium resistance of plants.

关键词： Potentilla sericea MYB Cadmium stress Gene cloning Functional analysis

Investigation ofβ—‑decay half‑life and delayed neutron emission with uncertainty analysis

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Nuclear Science and Techniques 2023年第1期34卷 111-123页

作者： yu‑Feng gao Bo‑Shuai Cai Cen‑Xi yuan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

β-decay half-life and β-delayed neutron emission(βn) are of great importance in the development of basic science and industrial applications, such as nuclear physics and nuclear energy, where β--decay plays an important role. Many theoretical models have been proposed to describe β-decay half-lives, whereas the systematic study of βn is still rare. This study aimed to investigate β--decay half-lives and βn probabilities through analytical formulas and by comparing them with experimental data. Analytical formulas for β--decay properties have been proposed by considering prominent factors, that is, decay energy,odevity, and the shell effect. The bootstrap method was used to simultaneously evaluate the total uncertainty on calculations,which was composed of statistic and systematic uncertainties. β--decay half-lives, βn probabilities, and the corresponding uncertainties were evaluated for the neutron-rich region. The experimental half-lives were well reproduced. Additional predictions are also presented with theoretical uncertainties, which helps to better understand the disparity between the experimental and theoretical results.

关键词： Neutron-rich nucleus -delayed neutron emissions Bootstrap method

Some basic questions on helicity inferred from vector magnetograms

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1749-1753页

作者： XU HaiQing gao yu ZHANG HongQi Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China

This paper summarizes current helicity measurements in the solar active regions (ARs). There is a basic agreement with the "hemispheric sign rule (HSR)" of the current helicity among different vector magnetographs through two solar cycles, but there is a large dispersion of the fraction of ARs following the HSR. In our sample, there are 50%-78% ARs in solar cycle 22 and 44%-79% ARs in cycle 23 following the HSR. A variation is also found in the fraction of the ARs following the HSR between different instruments even when the same ARs are selected. The difference also exists for the same instrument when the selected ARs are different. There are some differences in the variation of HSR with solar cycle for the individual helicity parameter inferred from different instruments. Factors which influence the correlation of different data sets are analyzed.

关键词： photosphere magnetic field helicity solar dynamo