Polymer brush-grafted nanoparticles have significant application value in fields such as gene therapy and targeted drug delivery. A profound understanding of the interaction mechanisms between these particles and cell membranes represents a critical scientific challenge in biophysics. Using the Self-Consistent Field Theory, this work systematically explores the transmembrane transport of polymer brush-grafted nanoparticles into giant vesicles. The impacts of critical parameters-polymer brush grafting density, nanoparticle size, and giant vesicle membrane thickness-on transport behavior are comprehensively elucidated. The findings reveal two distinct transmembrane transport mechanisms for polymer brush-grafted nanoparticles, which are governed by membrane thickness and grafting density. At high grafting density, the nanoparticles undergo direct transmembrane translocation; at low grafting density, transport occurs via endocytosis. Thermodynamic analysis identifies entropy as the dominant driving force for this process.

The self-assembly of polymer grafted nanoparticles is increasingly being applied in the field of functional materials. However, there is still a lack of analysis on the dynamic transformation paths of different self-assembly morphologies, which leads to the inability to achieve further precise regulation and targeted design in experiments and industrial production. In this paper the effects of block property, grafted chain length, ratio and grafting density on the self-assembly behavior and structure of polymer grafted flexible blocky nanoparticles are investigated by dissipative particle dynamics (DPD) simulation method through the construction of coarse-grained model of polymer grafted ternary nanoparticles. The influence and regulation mechanism of these factors the self-assembly structure transformation of flexible blocky nanoparticles are systematically studied, and a variety of structures such as dendritic structure, columnar structure, and bilayer membrane are obtained. The self-assembly structure of flexible blocky nanoparticles obtained in the study (such as bilayer membrane structure) provides a potential application basis for the design of drug carriers. By precisely regulating the specific structural characteristics of the system, it is possible to achieve efficient loading of drugs and targeted delivery functions, thus significantly improving the bioavailability and effect of drugs.

Active particle systems are a class of non-equilibrium systems composed of self-propelled Brownian particles; through interactions between particles within the system, a variety of intriguing collective behaviors can emerge. Based on Brownian dynamics simulations, this study investigates the formation and transition mechanisms of ordered structures in active particle systems regulated by light fields. The study reveals that, under light field regulation, active particles undergo large-scale phase separation behavior, forming specific ordered structures and enabling the dynamic transition between multiple ordered structures. This study systematically explores the effects of light fields on this dynamic phase transition and the corresponding regulatory mechanisms. The research findings provide important references for the precise regulation of collective structures in active systems and the fabrication of micro-nano intelligent devices.

We investigated the surface orthogonal patterning and bidirectional self-assembly of binary hairy nanoparticles (NPs) constructed by uniformly tethering a single NP with multiple V-shaped AB diblock copolymers using Brownian dynamics simulations in a poor solvent. At low concentration, the chain collapse and microphase separation of binary polymer brushes can lead to the patterning of the NP surface into A- and B-type orthogonal patches with various numbers of domains (valency), n = 1-6, that adopt spherical, linear, triangular, tetrahedral, square pyramidal, and pentagonal pyramidal configurations. There is a linear relationship between the valency and the average ratio of NP diameter to the polymers' unperturbed root-mean-square end-to-end distance for the corresponding valency. The linear slope depends on the grafting density and is independent of the interaction parameters between polymers. At high concentration, the orthogonal patch NPs serve as building blocks and exhibit directional attractions by overlapping the same type of domains, resulting in self-assembly into a series of fascinating architectures depending on the valency and polymer length. Notably, the 2-valent orthogonal patch NPs have the bidirectional bonding ability to form the two-dimensional (2D) square NP arrays by two distinct pathways. Simultaneously patching A and B blocks enables the one-step formation of 2D square arrays via bidirectional growth, whereas step-by-step patching causes the directional formation of 1D chains followed by 2D square arrays. Moreover, the gap between NPs in the 2D square arrays is related to the polymer length but independent of the NP diameter. These 2D square NP arrays are of significant value in practical applications such as integrated circuit manufacturing and nanotechnology.

Computer simulations are utilized to investigate the dynamic behavior of self-propelled particles(SPPs)within a com-plex obstacle environment.The findings reveal that SPPs exhibit three distinct aggregation states within the obstacle,each contingent on specific conditions.A phase diagram outlining the aggregation states concerning self-propulsion conditions is presented.The results illustrate a transition of SPPs from a dispersion state to a transition state as persistence time in-creases within the obstacle.Conversely,as the driving strength increases,self-propelled particles shift towards a cluster state.A systematic exploration of the interplay between driving strength,persistence time,and matching degree on the dynamic behavior of self-propelled particles is conducted.Furthermore,an analysis is performed on the spatial distribution of SPPs along the y-axis,capture rate,maximum capture probability,and mean-square displacement.The insights gained from this research make valuable contributions to understanding the capture and collection of active particles.

The lightning with two grounding points (TGP) is a special and more destructive lightning. Due to the lack of observational data, many physical problems of TGP lightning are still unclear. This paper attempts to establish a theoretical model to simulate the development process of TGP lightning. The simulation results show that the average horizontal distance between two grounding points is about half the average height of the branch point. Both branches move toward the ground at almost the same speed. The formation of TGP lightning seems to be independent of the height of the branch point. The results of our simulation are in good agreement with those found in nature for TGP lightning. This work contributes to a more comprehensive understanding of the TGP lightning. It also can provide reference for the modeling of lightning with multiple grounding points.

The self-assembly behavior of diblock copolymer/homopolymer/nanorods hybrid system under oscillation field is performed by using Cell Dynamics Scheme (CDS) and Brownian Dynamics (BD). The effects of the amplitude and frequency of the oscillation field on the formation and evolution of the mixture morphology are investigated systematically. It is found that the oscillation field plays an important role in the formation and transformation of the ordered structure. With the frequency increasing, the orientation of the lamellar structure transforms from parallel to the field direction to random angle and then to perpendicular to the field direction. Compared with the pure rod system, the addition of polymers has a combing effect. Under high amplitude and low frequency (\begin{document}$ {\rm{\omega }}\leqslant 0.01 $\end{document}) of the oscillation field, the arrangement of nanorods transforms from vertical to horizontal. However, under high amplitude and high frequency (\begin{document}$ \omega > 0.01 $\end{document}), the nanorods change from vertical/horizontal hybrid arrangement to vertical arrangement. The evolution of domain size and orientation angle of nanorods under oscillation field are further analysed. The results provide a new method and reference for fabricating and regulating the ordered structure of polymer nanocomposites.

With the emergence and rapid development of nanotechnology, the nanoparticles hybridized with multicomponent lipids are more and more used in gene delivery. These vectors interact with the cell membrane before entering into the cell. Therefore, the nature of this interaction is important in investigating multicomponent liposome-nanoparticle (MLP) transport across the cell membrane. In this paper the transport of MLPs across the membranes of giant vesicles (GVs) in solvents is studied by using the self-consistent field theory (SCFT). Based on the analysis of the MLP permeating the GV membranes, a simple transport model is proposed. The effects of the difference in membrane morphology and the size of the nanoparticle on the endocytosis are discussed systematically. The role of energy barriers in quasi-equilibrium is also examined. The results indicate that the interaction between MLP and GV is a spontaneous process and the energy barrier needs overcoming to form metastable intermediates. The results provide theoretical reference for better understanding the transmembrane transport process of nanoparticles, and guidance for relevant experimental studies as well.

采用基于金兹堡-朗道理论(Ginzburg-Landau Theory)的元胞动力学方法(Cell Dynamic System)研究光掩膜诱导的聚合物/纳米粒子共混体系的自组装行为.探讨掩膜、光照强度、聚合物组分比、纳米粒子浓度、聚合物-纳米粒子相互作用等因素对体系形貌形成和演化的影响,构建体系结构与相关参数的二维相图,同时分析结构形成的动力学过程,揭示各参数间的相互作用机理,获得了调控复合体系花样结构形成和转变的简便方法,为新型高性能微纳米材料的制备提供参考.

Abstract In this work, we study the potential of searching for triply charged Higgs boson originating from a complex Higgs quadruplet in the final state with at least three same-sign leptons. A detailed collider analysis of the SM backgrounds and signals is performed at a 100 TeV pp collider for the triply charged Higgs boson mass below 1 TeV and the Higgs quadruplet vacuum expectation value $$v_\Delta $$ v Δ ranging from $$1.5\times 10^{-9}~\text {GeV}$$ 1.5 × 10 - 9 GeV to $$1.3~\text {GeV}$$ 1.3 GeV and the mass splitting $$\Delta m$$ Δ m between the nearby states of the Higgs quadruplet satisfying $$|\Delta m|\lesssim 30~\text {GeV}$$ | Δ m | ≲ 30 GeV . About $$100~\text {fb}^{-1}$$ 100 fb - 1 of data are required at most for $$5\sigma $$ 5 σ discovery. We also revisit the sensitivity at the Large Hadron Collider (LHC) and find that $$5\sigma $$ 5 σ discovery of the triply charged Higgs boson below 1 TeV can be reached for a relatively small $$v_\Delta $$ v Δ . For example, if $$v_\Delta =10^{-6}~\text {GeV}$$ v Δ = 10 - 6 GeV and $$\Delta m=0$$ Δ m = 0 , the integrated luminosity of $$330~\text {fb}^{-1}$$ 330 fb - 1 is needed. But for a relatively large $$v_\Delta $$ v Δ , i.e., $$v_\Delta \gtrsim 10^{-3}~\text {GeV}$$ v Δ ≳ 10 - 3 GeV , the triply charged Higgs boson above about 800 GeV cannot be discovered even in the high-luminosity LHC era. For $$\Delta m>0$$ Δ m > 0 , the cascade decays are open and the sensitivity can be improved depending on the value of $$v_\Delta $$ v Δ .

Baryons with a heavy c-quark or a heavy b-quark and also two c-quarks have been discovered. These states are expected in QCD and therefore provide a test for the theory. There should be double beauty baryons, and also an intriguing possibility that baryons B-bc with a c-quark, a b-quark. These states are yet to be discovered. The main decay modes of B-bc are expected to be weak processes from theoretical understanding of their mass spectrum. These decay modes can provide crucial information about these heavy baryons B-bc. We analyze two body hadronic weak decays for B-bc using SU(3) flavor symmetry. Any one of the c and b decays will induce B-bc to decay. We find that the Cabibbo allowed decays B-bc -> B-b + M due to c -> su (d) over bar can be crucial for exploration. The LHC may have the sensitivity to discover such decays. Other B-bc decays due to b -> cq'(q) over bar are subleading. Several relations among branching ratios are obtained which can be used to test SU(3) flavor symmetry.

By using self-consistent field theory, the directed self-assembly of a diblock copolymer was studied with homopolymer-grafted particles. The four factors were investigated, such as the fraction of the A block, the brush density and the number and arrangement of particles. A varies ordered structures had been obtained, while a phase diagram was constructed as a function of the volume fraction of the A block and the brush density. The simulation results showed that the morphologies of the block copolymer were sensitive to the particle number and arrangement. Therefore, the self-assembly of the diblock copolymer can be controlled by increasing the particle number and by adjusting the arrangement of particles. A technique guide was provided by creating ordered patterns at the nanoscale.

本文采用基于金兹堡-朗道理论(Ginzburg-Landau Theory)的元胞动力学(Cell Dynamic System)方法研究了化学反应诱导的二元聚合物和纳米粒子共混体系的自组装行为.系统探讨了反应速率、粒子浓度、浸润强度等因素对体系相行为的影响.

The non-zero Dirac phases δq and δl in the CKM and PMNS mixing matrices signify CP violation. In general they are independent. Experimental data including recent T2K results show, however, that in the original KM parameterization for the mixing matrix, the sum δKMq+δKMl is close to zero with δKMq to be approximately π/2. The KM parameterization may have provided some hints that these phases are actually related and CP is maximally violated. We show that this sum rule can be accommodated in models with spontaneous CP violation where both phases originate from a non-trivial common spontaneous CP violating maximized phase in the Higgs potential. We find some interesting phenomenological consequences for flavor changing neutral current and CP violation for such a model. In particular, data from Bs−B¯s mixing provide very strong constraints on the mass scale for the new neutral scalars in the model, yet the model still allows the electric dipole moments of electron and neutron to reach to their current upper bounds. The model can be tested by near future experiments.

A vortex is a common ratchet phenomenon in active systems. The spatial symmetry is usually broken by introducing asymmetric shapes or spontaneously by collective motion in the presence of hydrodynamic interactions or other alignment effects. Unexpectedly, we observe, by simulations, the formation of a vortex in the simplest model of a circular obstacle immersed in a bath of spherical self-propelled particles. No symmetry-breaking factors mentioned above are included in this model. The vortex forms only when the particle activity is high, i.e. large persistence. The obstacle size is also a key factor and the vortex only forms in a limited range of obstacle sizes. The sustainment of the vortex originates from the bias of the rotating particle cluster around the obstacle in accepting the incoming particles based on their propelling directions. Our results provide new understanding of and insights into the spontaneous symmetry-breaking and ratchet phenomena in active matter.

The non-zero Dirac phases δq and δl in the CKM and PMNS mixing matrices signify CP violation. In general they are independent. Experimental data including recent T2K results show, however, that in the original KM parameterization for the mixing matrix, the sum δKMq+δKMl is close to zero with δKMq to be approximately π/2. The KM parameterization may have provided some hints that these phases are actually related and CP is maximally violated. We show that this sum rule can be accommodated in models with spontaneous CP violation where both phases originate from a non-trivial common spontaneous CP violating maximized phase in the Higgs potential. We find some interesting phenomenological consequences for flavor changing neutral current and CP violation for such a model. In particular, data from Bs−B¯s mixing provide very strong constraints on the mass scale for the new neutral scalars in the model, yet the model still allows the electric dipole moments of electron and neutron to reach to their current upper bounds. The model can be tested by near future experiments.

A new U(1)_X gauge boson field X can have renormalizable kinetic mixing with the standard model (SM) U(1)_Y gauge boson field Y. This mixing induces interactions of X with SM particles even though X starts as a dark photon without such interactions. If the U(1)_X is not broken, both the dark photon field X and the photon field A are massless. One cannot determine which one of them is the physical dark photon or the photon by just looking at kinetic terms in the Lagrangian. We revisit this issue and show explicitly that when all contributions are included, all physical processes do not depend on which basis is used and the kinetic mixing effects do not show up in electromagnetic and weak interactions if only SM particles are involved in the calculations. On the other hand, the kinetic mixing provides a portal for probing the dark sector beyond the SM. We update constraints on the millicharged dark sector particles from the Lamb shift and lepton g-2 measurements.

Considerable information has been obtained about neutrino mixing matrix. Present data show that in the particle data group (PDG) parametrization, the 2–3 mixing angle and the CP violating phase are consistent with [Formula: see text] and [Formula: see text], respectively. A lot of efforts have been devoted to constructing models in realizing a mixing matrix with these values. However, the particular angles and phase are parametrization convention dependent. The meaning about the specific values for mixing angle and phase needs to be clarified. Using the well-known nine independent ways of parametrizing the mixing matrix, we show in detail how the mixing angles and phase change with conventions even with the 2–3 mixing angle to be [Formula: see text] and the CP violating phase to be [Formula: see text]. The original Kobayashi–Maskawa and an additional one belong to such a category. The other 6 parametrizations have mixing angles and phase very different values from those in the PDG parametrization although the physical effects are the same. Therefore one should give the specific parametrization convention when making statements about values for mixing angles and phase.

We investigated phase transitions in a diblock copolymer–homopolymer hybrid system blended with nanorods（NRs）by using the time-dependent Ginzburg–Landau theory. We systematically studied the effects of the number, length and infiltration properties of the NRs on the self-assembly of the composites and the phase transitions occurring in the material.An analysis of the phase diagram was carried out to obtain the formation conditions of sea island structure nanorodbased aggregate, sea island structure nanorod-based dispersion, lamellar structure nanorod-based multilayer arrangement and nanowire structure. Further analysis of the evolution of the domain sizes and the distribution of the nanorod angle microphase structure was performed. Our simulation provides theoretical guidance for the preparation of ordered nanowire structures and a reference to improve the function of a polymer nanocomposite material.