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Polyelectrolyte Complexes and Coacervates Formed by De novo-Designed Peptides and Oligonucleotide

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Chinese Journal of Polymer Science 2024年第9期42卷 1333-1340,I0007页

作者： tian-hao Ren De-Hai Liang Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

The liquid-liquid phase separation of biopolymers in living cells contains multiple interactions and occurs in a dynamic *** the regulation mechanism is still a *** this work,we designed a series of peptides(XXLY)_(6)SSSGSS and studied their complexation and coacervation behavior with single-stranded ***“X”and“Y”are varied to combine known amounts of charged and non-charged amino acids,together with the introduction of secondary structures and pH *** show that the electrostatic interaction,which is described as charge density,controls both the strength of complexation and the degree of chain relaxation,and thus determines the growth and size of the *** hydrophobic interaction is prominent when the charges are ***,the secondary structures of peptides exhibit profound effect on the morphology of the phases,such as solid phase to liquid phase *** study gains insight into the phase separation under physiological *** is also helpful to create coacervates with desirable structures and functions.

关键词： Polyelectrolyte complex Coacervate Peptides Secondary structure Electrostatic interaction

Performance evaluation of HY-2 series satellites in marine gravity field recovery

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Geodesy and Geodynamics 2024年第4期15卷 397-403页

作者： Ruijie hao Xiaoyun wan Keyan Zhang School of Land Science and Technology China University of Geosciences(Beijing)Beijing100083China School of Geospatial Engineering and Science Sun Yat-Sen UniversityZhuhai519082China

China has successfully launched four Haiyang-2(HY-2)series altimetry ***-2A has attracted significant attention in gravity field recovery,but the performance of other HY-2 series satellites,including HY-2B/C/D,is seldom *** study evaluated the performance of all the HY-2 series satellites in recovering marine gravity ***,the crossover discrepancies in sea surface height of the four satellites,HY-2A,HY-2B,HY-2C,and HY-2D,were analyzed to assess their altimetry *** was found that HY-2B had the best altimetry quality,followed by ***,different combina-tions of altimetry data were used to calculate vertical deflections and gravity anomalies in the South China Sea(112°E-119°E,12°N-20°N).The results showed that combining data from HY-2B,HY-2C,and HY-2D improved the inversion accuracy of gravity anomalies by 0.3 mGal compared to using HY-2A data ***-2C and HY-2D contributed to enhancing the accuracy of the east component of vertical deflections.

关键词： Satellite altimetry HY-2 Sea surfaceheight Marinegravityfield

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： tian-hao Yang Tong Wu Qiang Fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Effect of Fe Addition on Dehydrogenation Performance of Methylcyclohexance over Pt/Al_(2)O_(3)

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 12-18页

作者： Tong Fengya tian hao wang hao Miao Changxi Song Lei Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai201208

Catalysts with varying Fe contents were prepared using a sequential impregnation method to investigate the effects of Fe addition on the physicochemical properties of Pt/Al_(2)O_(3) and their performance in methylcyclohexane(MCH)*** results demonstrated that the addition of Fe to Pt/Al_(2)O_(3) enhanced the electron density of Pt and improved catalytic activity,while exhibiting negligible influence on the catalytic selectivity for *** the Fe content was 0.057%,the catalyst exhibited the highest MCH consumption rate,which was approximately two times higher than that of the catalyst without ***,the incorporation of Fe inhibited the formation of coke and reduced the quantity of coke deposits on the catalyst,thereby improving its catalytic ***,Fe shows promise as a prospective secondary element for Pt/Al_(2)O_(3) to enhance the MCH dehydrogenation performance.

关键词： methylcyclohexane dehydrogenation hydrogen storage deactivation Fe addition

Systematic study of the synthesis of heavy and superheavy nuclei in 48Ca-induced fusion-evaporation reactions

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Nuclear Science and Techniques 2024年第7期35卷 157-172页

作者： Shi-hao Zhu tian-Liang Zhao Xiao-Jun Bao Department of Physics Collaborative Innovation Center for Quantum EffectsKey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha410081China School of Nuclear Science and Technology Lanzhou UniversityLanzhou730000China School of Physics Xi’an Jiaotong UniversityXi’an710049China

We systematically studied the evaporation residue cross sections of ^(48)Ca-induced reactions on lanthanide and actinide target nuclei under the Dinuclear System(DNS)model framework to check the reliability and applicability of the *** produce new proton-rich Fl and Lv isotopes through hot fusion reactions in the superheavy element region with Z≥104,we utilized the reactions ^(48)Ca+^(236,238,239) Pu and ^(48)Ca+^(242,243,244,250) ***,owing to the detection limit of available equipment(0.1 pb),only 283Fl and 287−289Lv,which have the maximum evaporation residue cross section values of 0.149,0.130,9.522,and 0.309 pb,respectively,can be ***,to produce neutron-deficient isotopes of actinides near the proton drip line with Z=93−100,we attempted to generate the new isotopes(224−227Pu,228−232,237Cm)using the reactions ^(48)Ca+180,182,183 W and ^(48)Ca+^(184,186,187,192) *** maximum evaporation residue cross section values are 0.07,0.06,0.26,and 0.30 nb for the former set of reactions,and 1.96 pb,5.73 pb,12.16 pb,19.39 pb,54.79 pb,and 6.45 nb for the latter,*** results are expected to provide new information for the future synthesis of unknown neutron-deficient isotopes.

关键词： Dinuclear system(DNS)model Evaporation residue cross section Neutron-deficient isotopes

Selective oxidation using in-situ generated hydrogen peroxide over titanosilicates

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Chinese Journal of Structural Chemistry 2024年第6期43卷 12-14页

作者： Zhipeng wan hao Xu Peng Wu State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China Institute of Eco-Chongming Shanghai202162China

Titanosilicates are a class of heteroatom-containing zeolitic materials with tetrahedrally coordinated Ti^(4+)ions incorporated into crystalline zeolite frameworks,with TS-1,Ti-MWW and Ti-MOR as representative and attractive selective oxidation *** liquid-phase oxidations of a variety of substrates such as olefins and ketones with the green oxidant of H_(2)O_(2)over titanosilicates under mild conditions have attracted considerable research interests in the clean production of fine and bulk chemicals,among which propylene epoxidation and cyclohexanone ammoximation have been industrialized[1].

关键词： silicate zeolite propylene

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu Zhang Yi Zhang Wen-hao tian Yan Li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution

Anderson Acceleration of Gradient Methods with Energy for Optimization Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1299-1318页

作者： Hailiang Liu Jia-hao He Xuping tian Department of Mathematics Iowa State UniversityAmesIAUSA Department of Agricultural and Biosystems Engineering Iowa State UniversityAmesIAUSA

Anderson acceleration(AA)is an extrapolation technique designed to speed up fixed-point *** optimization problems,we propose a novel algorithm by combining the AA with the energy adaptive gradient method(AEGD)[arXiv:2010.05109].The feasibility of our algorithm is ensured in light of the convergence theory for AEGD,though it is not a fixed-point *** provide rigorous convergence rates of AA for gradient descent(GD)by an acceleration factor of the gain at each implementation of *** experimental results show that the proposed AA-AEGD algorithm requires little tuning of hyperparameters and exhibits superior fast convergence.

关键词： Anderson acceleration(AA) Gradient descent(GD) Energy stability

Theoretical assessment of discharge effects on the decomposition tendency of C_(6)F_(12)O over metallic surfaces

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High Voltage 2024年第4期9卷 862-869页

作者： Zhaolun Cui Yanpeng hao Shuangshuang tian Xiaoxing Zhang Yashuang Zheng School of Electric Power Engineering South China University of TechnologyGuangzhouChina State Key Laboratory of Power Transmission Equipment Technology(Chongqing University) ChongqingChina School of Electrical and Electronic Engineering Hubei University of TechnologyWuhanChina

C_(6)F_(12)O is proposed to be one potential eco-friendly insulation gas to replace ***,the assessment of its decomposition properties and the compatibility with metal electrodes in discharge faults is still challenging,which greatly hinders the development of its insulation and arc-extinction ***,a theoretical method is proposed to reasonably address the discharge effects on C_(6)F_(12)O decomposition over typical Cu and Al electrodes at atomic *** results show that both the external electric field and the excess electrons could affect the activation of C_(6)F_(12)O by changing the electron acceptance of C_(6)F_(12)O and the orbital hybridisation during the surface *** metal surfaces,the C-F single bond in adsorbed C_(6)F_(12)O is the weakest position to decompose,and its cleavage could be promoted by the discharge *** the C-F breaking,the C-C cleavage remains unfavourable on Cu(111),but it is significantly promoted on Al(111),indicating a higher corrosion risk on the Al surface via continuous C_(6)F_(12)O *** proposed method as a valid supplement to the experiment reveals the discharge effects and the decomposition tendency of C_(6)F_(12)O on metal electrodes in discharge faults,which broadens the means for insulation gas evaluation.

关键词： corrosion insulation cleavage