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Complexity of charged anisotropic spherically symmetric fluids in f(G)gravity

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Communications in Theoretical Physics 2023年第3期75卷 91-104页

作者： z Yousaf m z Bhatti m m m Nasir Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The previous ideology of complexity factor for the dynamical spheres[Herrera et al 2018,***.D,98,104059]is extended for the influence of charge.A dynamical spherically symmetric non-dissipative and dissipative self-gravitating structure is examined in the presence of maxwell f(G)gravity to examine the complexity *** pattern of evolution is studied with the minimal complexity *** complexity factor remains the same for the structure of fluid distribution,while we examine homologous constraints for the most basic evolution *** calculate the structure scalars which play an important role in order to understand the fundamental properties of the *** fluid is geodesic as well as shearing for the dissipative case and there is a large number of *** the non-dissipative fluid distribution,a shear-free,homogeneous and isotropic,geodesic fluid correlates with the evolving homologous and vanishing complexity *** implication of the condition of vanishing complexity factor and stability are discussed at the end.

关键词： gravitation anisotropy complexity hydrodynamics

Surface modification of tungsten oxide by oxygen vacancies for hydrogen adsorption

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Journal of materials Science & Technology 2022年第22期117卷 23-35页

作者： Q.zhang F.W.tang z.zhao z.R.Nie X.Y.Song Faculty of materials and manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing the adsorption process of hydrogen on surface of tungsten oxide was proposed based on the first-principle calculations. multiple factors such as type of active surface, adsorption site and distribution of oxygen vacancies were considered to evaluate the hydrogen adsorption capability of tungsten oxide. The adsorption Gibbs free energies, electronic structures and bonding characteristics under various conditions were examined to reveal the influence of oxygen vacancies on the surface. It is found that the capability of hydrogen adsorption of tungsten oxide can be significantly enhanced by adjusting the oxygen vacancy on the outermost layer of certain active surfaces. The modeling predicts that the surface structure stability and gas adsorption ability of tungsten oxide can be simultaneously improved through the formation of W–H bonds. The proposed strategy for moderating surface provides a new approach to obtain excellent gas-sensitive metal oxide materials.

关键词： metal oxide Gas-sensitive material Surface adsorption Oxygen vacancy First-principles calculation

THEORETICAL INVESTIGATION ON BY-ONLY-CURRENT ELECTROmAGNETIC SEPARATION OF INCLUSION FROm mOLTEN mETALS

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Acta metallurgica Sinica(English Letters) 2002年第5期15卷 416-424页

作者： B. W. zhang, z.m. Ren , Y.B. zhong, K. Deng and K.D. XuShanghai Enhanced Laboratory of metallurgy,Shanghai University, Shanghai 200072, China Shanghai Enhanced Laboratory of metallurgy Shanghai University

The electromagnetic field under applied AC and DC current in round and rectangular pipe was systematically investigated, then a concept of 'equivalent current density' was proposed for evaluating the inhomogeneous electromagnetic pinch force, and the mono-component removal efficiency and the overall removal efficiency of inclusion were formulated. It is founded that flat pipe is superior to round pipe for the electromagnetic removal of inclusion, and DC current can get a higher removal efficiency than A C current due to absence of skin phenomenon. Under usual condition, a removal efficiency of 52% for 10μm inclusion or more than 92% for 20μm inclusion can be achieved by imposing a current density of 3×106A/m2 in a flat pipe.

关键词： inclusion electromagnetic separation efficiency of removal equivalent current density

Correlation Between Local Atomic Symmetry and mechanical Properties in metallic Glasses

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Journal of materials Science & Technology 2014年第6期30卷 551-559页

作者： m.z.Li Department of Physics Renmin University of China Beijing Key Laboratory of Opto-Electronic Functional materials & micro-nano Devices Renmin University of China

The local atomic symmetry was investigated and discussed for understanding mechanical, vibrational and dynamical properties in metallic glasses. Local five-fold symmetry was defined based on the ratio of pentagons to the total number of faces in a Voronoi cluster analyzed by Voronoi tessellation method. It is found that the plastic deformation prefer to be initiated in the regions with less degree of local five-fold symmetry （LFFS） and propagate gradually toward the region with more degree of LFFS. On the other hand, the local structures having less degree of LFFS contribute more to the soft low-frequency modes, and thus the so-called boson peak, while those with more degree of LFFS participate more in moderate- and high- frequency modes in metallic glasses. The relationship between local atomic symmetry and structural heterogeneity, mechanical heterogeneity, and glass transition was also discussed. It is shown that local atomic symmetry could be a general structural indicator in metallic liquids and glasses for better understanding the structure-property relationship in amorphous alloys.

关键词： metallic glasses Atomic symmetry Deformation molecular dynamics

Rare earth elements(lanthanum,cerium and erbium)doped black oxygen deficient Bi_(2)O_(3)-Bi_(2)O_(3-x) as novel photocatalysts enhanced photocatalytic performance

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Journal of Rare Earths 2022年第7期40卷 1053-1062页

作者： Jin tang zhili Chen Xiaolong Yu Walter ztang College of Environmental Science and Engineering Guilin University of TechnologyGuilin 541006China Department of Civil and Environmental Engineering Florida International UniversityMiamiFL33174USA Guangdong Provincial Key Laboratory of Petrochemical Pollution Processes and Control School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China

Novel black oxygen deficient bismuth oxide(Bi_(2)O_(3)-Bi_(2)O_(3-x))photocatalytic material was successfully prepared by a two zone temperature controlled muffle furnace *** lanthanum,cerium and erbium ions are successfully doped into Bi_(2)O_(3)-Bi_(2)O_(3-x) with the average contents of 10.77 wt%,7.62 wt%and 8,14 wt%,*** re sults show that a large number of oxygen vacancies exist in Bi_(2)O_(3)-Bi_(2)O_(3-x).La^(3+)Ce^(3+)and Er^(3+)act as electron acceptors to temporarily trap the photo-generated *** XPS spectrum show Bi-O band in Bi_(2)O_(3)-Bi_(2)O_(3-x) and the O 1s peak of Ce/Bi_(2)O_(3)-Bi_(2)O_(3-x) move toward the direction of low binding *** phenomena fully prove that the separation of photogenerated electron-hole pairs will be more effectual,so as to reduce the possibility of charge carrier *** radical scavenging experiments and electron spin resonance detections confirm that the conduction band of the original Bi_(2)O_(3)can easily receive photogenerated electrons,while the valence band of the modified Bi_(2)O_(3)-Bi_(2)O_(3-x) tends to accept photogenerated holes and then forms the circulation ***,Ce/Bi_(2)O_(3)-Bi_(2)O_(3-x) can degrade tetracycline hydrochloride up to 90.15%.This research provides some new insights into developing green and recyclable photocatalysts for the remediation of antibiotic contamination.

关键词： Oxygen deficient Rare earth doping Photocatalysis Degradation mechanism Tetracycline hydrochloride

multiplexed imaging detection of live cell intracellular changes in early apoptosis with aggregation-induced emission fluorogens

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Science China Chemistry 2018年第8期61卷 892-897页

作者： Yabin zhou Haixiang Liu Na zhao zhiming Wang michael z.m.chael Ni Xie Ben zhong tang Youhong tang Faculty of Biological Engineering Sichuan University of Science and Engineering Department of Chemistry the Hong Kong University of Science and Technology Centre for Nano Scale Science and Technology College of Science and Engineering Flinders University Department of Gastroenterology and Hepatology Flinders Centre for Innovation in Cancer Flinders University AIEgen Biotech Co. Limited

Apoptosis is an important process for maintaining tissue homeostasis and eliminating abnormal cells in multicellular *** in apoptosis often leads to severe diseases such as cancers. Better understanding of its mechanisms and processes is therefore important. Accompanying molecular biology events of apoptosis is a series of cellular morphology changes: nucleus condensation, cell shrinkage and rounding, cell surface blebbing, dynamic blebbing, apoptotic membrane protrusions and nucleus fragmentations and finally, the formation and release of apoptotic bodies. It is difficult to detect cellular changes in the early phase of apoptosis due to the subtle changes at this phase. In the current study, we induced apoptosis in He La cells with H2 O2 and used nuclear dye Hoechst 33258, mitochondria, lysosome and cytoplasmic protein specific aggregation-induced emission fluorogens(AIEgens), TPE-Ph-In, 2 m-DABS and BSPOTPE to successfully perform live cell multiplexed imaging to investigate early apoptosis cellular events. We showed the gradual dissipation of mitochondria membrane potential until it is nondetectable by TPE-Ph-In. Increased mitophagy detected by TPE-Ph-In and 2 m-DABS, condensed nucleus detected by Hoechst33258, increased permeability and/or reduced integrity of nuclear membrane, and increased intracellular vesicles detected by2 m-DABS are some of the early events of apoptosis.

关键词： apoptosis multiplexed imaging He La aggregation-induced emission fluorogens(AIEgens)

STUDY ON THE FRACTURE PROCESS OF AN AS CAST zn 27WT% Al ALLOY

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Acta metallurgica Sinica(English Letters) 1999年第4期12卷 578-580页

作者： z.m. Ding and L.m. zhang Departmentof material Science and Engineering, Dalian Railway Institute,Dalian 116028 ,China

Thefracture processof an ascast zA27 alloy under thetensiletest atthe room temperature wasstudied. Theresultsshow thatthecracksof zA27 alloy form at(α+ η)eutectic phaseand develop bypropagatingalongthe(α+ η) phaseandcuttingthroughthe dendriteαphaseand εphase. Theinfluenceof every phasein zA27 on thestrength and ductility was ana lyzed.

关键词： SzA27 alloy tensilefracture fracture process

Improving the strength and SCC resistance of an Al-5mg-3zn alloy with low-angle grain boundary structure

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Journal of materials Science & Technology 2023年第30期161卷 63-73页

作者： z.C.tang W.Xu D.Y.zhao B.zhang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The strength of traditional Al-mg alloys is relatively low because it mainly relies on solid solution *** a third component to form precipitation can improve their strength,but it usually leads to high-stress corrosion cracking(SCC)sensitivity due to the formation of high-density precipitates at grain boundaries(GBs).So far,it is still challenging to improve the strength of Al-mg alloys without re-ducing SCC ***,a nanostructured Al-5mg-3 zn alloy with a good yield strength of 336 mPa and good elongation was successfully *** dynamic plastic deformation and appropriate anneal-ing treatment,near-equiaxed nanograins were introduced in the nanostructured Al-5mg-3 zn alloy with a high proportion(71%)of the low-angle grain *** statistical investigations show that the pre-cipitation of active T’phase at GBs has been greatly suppressed in the nanostructured Al-5mg-3 zn alloy at sensitized conditions,and the area fraction of GB precipitates is reduced from 72%to 21%,which sig-nificantly decreases the SCC *** study provides guidance for developing advanced Al-mg alloy with high SCC resistance.

关键词： Al-5mg-3 zn alloy Stress corrosion cracking Low angle grain boundary Nanostructured Dynamic plastic deformation

ANISOTROPY OF (1×1)-SURFACE FREE ENERGIES OF CRYSTALS

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Acta metallurgica Sinica(English Letters) 2001年第6期14卷 485-492页

作者： z.m. Yu (Department of materials Science and Engineering, Central South University, Changsha 410083, China) A. Flodstrom (Royal Institute of Technology, KTH, Office of the President, Valhallavdgen 79, S-100 44 Stockholm, Sweden) Dept. of mat. Sci. and Eng. Central South Univ. Changsha 410083 China

The surface free energy (SFE) of (1× 1)-surfaces of crystals, without reconstructionand adsorption, is calculated using a bond-broken mode. In the mode, the potentialenergy of the crystals is treated as a sum of the energies of the bonds connectingpair-wise atoms (u-bonds). The SFE is calculated based on the bond energy and thearea density of dangling bonds which depends on the structure of the surface. Theresults provide a general expression for the SFE in terms of the bond energy (E)and the bond length (do) of the crystal and miller indices hkl. The anisotropy ofthe SFE is therefore completely determined with the expression. As the examples,considering the nearest-neighboring bonding, the SFEs of sc, fcc, bcc and cth (cubictetrahedral) crystals are discussed, respectively. Wulff plots of bcc and fcc crystalsare then obtained. The equilibrium forms (EFs) of these crystals ave consequentlygot from their Wulff plots, respectively. It is found that the EFs of bcc and fcc arerespectively the rhombic dodecahedron and the truncated-octahedron that are their firstBrillouin zones, respectively.

关键词： surface free energy crystal geometrical thermodynamics