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Relations between SMBH Parameters and jet Generation and Efficiency in Blazars

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Research in Astronomy and Astrophysics 2023年第11期23卷 67-83页

作者： H.zhang H.j.zhang Department of Physics Yunnan Normal UniversityKunming 650092China

We analyzed the relationship between several basic parameters describing supermassive black holes such as jet power,black hole spin,accretion disk magnetic field,black hole mass,*** found that there is a general correlation between these parameters,such as jet power is significantly positively correlated with black hole spin,while black hole mass is significantly negatively correlated with black hole *** apprehend these relationships,we consider the Blandford–Znajek model to be superior to the Blandford–Payne *** is also found that the intrinsic gamma luminosity of the FSRQs has a positive correlation with the accretion disk magnetic field,while the intrinsic gamma luminosity of the BL Lacs has a negative correlation with the accretion disk magnetic field.A feedback effect may exist between accretion disk accretion rate and magnetic field,which may be the key to the evolution between BL Lacs and *** is no significant difference in the jet power and jet generation efficiency of FSRQs and BL Lacs,which suggests that the jets are generated by the same *** contribution rate of accretion rate to jet generation efficiency is high,while the contribution rate of accretion rate to jet power is very low.

关键词： galaxies:evolution galaxies:fundamental parameters galaxies:jets

Deformation behaviors of Cu bicrystals with an inclined twin boundary at multiple scales

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journal of Materials Science & Technology 2017年第7期33卷 698-702页

作者： L.L.Li Z.j.zhang P.zhang j.Tan j.B.Yang Z.F.zhang Shenyaag National Laboratory for Materials Science lastitute of Metal Research Chinese Academy of Sciences Shenyaag 110016 China

Cu bicrystals of different sizes with a sole twin boundary（TB） inclined at 45？with respect to the loading direction were deformed under unidirectional and cyclic loading, respectively. It is found that the slip bands（SBs） parallel to the TB can be activated near the TB at all scales without obeying the Schmid＇s *** is concerned with the local stress enhancement in the macroscale while it is more closely related to the scarce dislocation sources in the microscale. Moreover, a wedge-shaped zone formed near the TB in the microscale ascribed to the limited specimen size.

关键词： Bicrystal Micropillar Twin boundary Schmid factors Size effect

Subvellerolactone　C，　a　New　Lactarane　Sesquiterpene　from　Lactarius　Subvellereus

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Chinese Chemical Letters 1996年第12期7卷 1097-1099页

作者： zhang, j Feng, XZ CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIjING UNION MED COLL BEIJING 100050PEOPLES R CHINA

Subvellerolactone C(I), a new 3, 8-oxa-13-hydroxy-1 acrar-6-en-5-oic acid γ-lactone was isolated from the fruit bodies of Lactarius subvellereus (Russulaceae), and its structure was elucidated by means of spectroscop... 详细信息

关键词： Subvellereus Lactarius New Sesquiterpene Lactarane

Synthesis of a chiral tricyclo[5.2.1.02.6]-deca-4,8-dien-3-one

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Chinese journal of Chemistry 1995年第3期13卷 284-287页

作者： LIU, ZY zhang, j CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

In recent years we have been interested in the synthesis of natural products by retro Diels-Alder reaction.A rogod ,p;eci;e tricyclo[5.***.1.0-deca-4,8-dien-

关键词： CHIRAL TRICYCLODECADIENONE ESTRAPENTANENOL DIELS-ALDER REACTION QUINONE

Methylation status of p16 gene in colorectal carcinoma and normal colonic mucosa

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World journal of Gastroenterology 1999年第5期5卷 451-454页

作者： zhang j Lai MD Chen j Hangzhou Railway Cent Hosp Dept Clin Pathol Hangzhou 310000 Zhejiang Provin Peoples R China Zhejiang Univ Sch Med Dept Pathol Hangzhou 310006 Zhejiang Provin Peoples R China

INTRODUCTIONp16 gene (also known as MTS-1, INK4a, CDKN2A), located on chromosome 9p21, is a G1-specific cell-cycle regulatory gene. It is composed of three exons, which encode 156 amino acids[1]. The gene is frequently inactivated in many human cancers. Unlike other tumor-suppressor genes that are commonly inactivated by point mutations, small homozygous deletions and methylation of the promoter represent the major mechanism of p16 gene inactivation[2,3]. In the Western countries, colorectal carcinoma ranks first among malignant tumors. The mortality from colorectal carcinoma has been rapidly growing in China in the last two to three decades. The genetic alterations involved in this tumor are still unclear. Rare mutation and infrequent deletion of p16 gene in primary colorectal carcinoma has been widely reported[4]. There were a few papers on p16 gene methylation in colorectal carcinoma, but the results were contradictory[5,6]. In this study, we have examined a total of 60 samples of colorectal carcinoma and paired 60 samples of the normal colonic mucosa for methylation by means of PCR-based methylation assay. There is infrequent methylation in the promoter of p16 gene both in colorectal carcinoma and normal colonic mucosa. The methylation status in 5′ CpG island of p16 gene in colorectal carcinoma is not related to the clinical pathologic parameters of these tumors.

关键词： Colonic mucosa colorectal neoplasms p16 gene methylation

Regulation of Power Conversion in Fuel Cells

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Chemical Research in Chinese Universities 2004年第4期20卷 466-469页

作者： zhang j. K. Scott School of Chemical Engineering & Advanced Materials University of Newcastle upon Tyne Newcastle upon TyneSchool of Chemical Engineering & Advanced Materials University of Newcastle upon Tyne Newcastle upon Tyne NE1 7RU UK NE1 7RU UK

Here we report a regulation about power conversion in fuel cells. This regulation is expressed as that total power produced by fuel cells is always proportional to the square of the potential difference between the \{equilibrium\} potential and work potential. With this regulation we deduced fuel cell performance equation which can describe the potential *** current performance curves, namely, polarization curves of fuel cells with three power source parameters: equilibrium potential E_0; internal resistance R; and power conversion coefficient K. The concept of the power conversion coefficient is a new criterion to evaluate and compare the characteristics and capacity of different fuel cells. The calculated values obtained with this equation agree with practical performance of different types of fuel cells.

关键词： Fuel cell Power conversion coefficient Internal resistance Performance Potential

Molecular diffusion in ternary poly(vinyl alcohol)solutions

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Frontiers of Chemical Science and Engineering 2022年第6期16卷 1003-1016页

作者： Katarzyna Majerczak Ophelie Squillace Zhiwei Shi Zhanping zhang Zhenyu j.zhang School of Chemical Engineering University of BirminghamBirmingham B152TTUK The Procter and Gamble Company CincinnatiOH 45040USA

The diffusion kinetics of a molecular probe-rhodamine B-in ternary aqueous solutions containing poly(vinyl alcohol),glycerol,and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light *** show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical *** presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration,but significantly slows down the diffiision of rhodamine B above 3.9%(w/v)due to a dominating steric inhibition ***,introducing surfactants(cationic/nonionic/anionic)to the system results in a decreased diffusion coefficient of the molecular *** solutions containing nonionic surfactant,this can be explained by an increased crowding *** ternary poly(vinyl alcohol)solutions containing cationic or anionic surfactant,surfactant-polymer and surfactant-rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffiisivity of rhodamine *** results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds,and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词： fluorescence correlation spectroscopy poly(vinyl alcohol) anomalous diffusion crowding effects dynamic light scattering binding effects rhodamine B

Design and optimization of the composition and mechanical properties for non-equiatomic CoCrNi medium-entropy alloys

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journal of Materials Science & Technology 2023年第8期139卷 232-244页

作者： j.X.Yan Z.j.zhang P.zhang j.H.Liu H.Yu Q.M.Hu j.B.Yang Z.F.zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China chool of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Shenyang University of TechnologyShenyang 111003China

The development of multi-principal element alloys(MPEAs,also called as high-or medium-entropy al-loys,HEAs/MEAs)provides tremendous possibilities for materials ***,designing MPEAs with desirable mechanical properties confronts great challenges due to their vast composition *** this work,we provide an essential criterion to efficiently screen the CoCrNi MEAs with outstanding strength-ductility *** negative Gibbs free energy difference△E_(FCC-BCC)between the face-centered cubic(FCC)and body-centered cubic(BCC)phases,the enhancement of shear modulus G and the decline of stacking fault energy(SFE)γ_(isf)are combined as three requisites to improve the FCC phase stability,yield strength,deformation mechanisms,work-hardening ability and ductility in the *** effects of chemical composition on△E_(FCC-BCC),G andγisf were investigated with the first principles calculations for Co_(x)Cr_(33)Ni_(67-x),Co_(33)Cr_(y)Ni_(67-y)and Co_(z)Cr_(66-z)Ni_(34)(0≤x,y≤67 and 0≤z≤66)*** on the essential criterion and the calculation results,the composition space that displays the neg-ative Gibbs free energy difference△E_(FCC-BCC),highest shear modulus G and lowest SFEγ_(isf)was screened with the target on the combination of high strength and excellent *** this context,the optimal composition space of Co-Cr-Ni alloys was predicted as 60 at.%-67 at.%Co,30 at.%-35 at.%Cr and 0 at.%-6 at.%Ni,which coincides well with the previous experimental evidence for Co_(55)Cr_(40)Ni_(5)*** valid-ity of essential criterion is further proved after systematic comparison with numerous experimental data,which demonstrates that the essential criterion can provide significant guidance for the quick exploitation of strong and ductile MEAs and promote the development and application of MPEAs.

关键词： Medium-entropy alloys First-principles calculations Phase stability Stacking-fault energy Strength Ductility

Mechanism transition of cross slip with stress and temperature in face-centered cubic metals

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journal of Materials Science & Technology 2020年第22期54卷 159-171页

作者： K.Q.Li Z.j.zhang j.X.Yan j.B.Yang Z.F.zhang Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

A/2 screw dislocation is commonly dissociated into two /6 Shockley partial dislocations on{111} planes in face-centered cubic *** the two partials are not purely screw,different mechanisms of cross-slip could take place,depending on the stacking fault energy,applied stress and tempe *** is crucial to classify the mechanisms of cross-slip because each mechanism possesses its own reaction path with a special activation *** this work,molecular dynamics simulations have been performed systematically to explore the cross-slip mechanism under different stresses and temperatures in three different metals Ag,Cu and Ni that have different stacking fault energies of 17.8,44.4 and 126.8 mj/m^2,re *** Ag and Cu with low stacking fault energy,it is observed that the cross-slip mechanism of screw dislocations changes from the Fleischer obtuse angle(FLOA),to the Friedel-Escaig(FE),and then to the FL acute angle(FLAA) at low temperatures,with increasing the applied ***,when the temperature increases,the FE mechanism gradually becomes dominant,while the FLAA only occurs at the high stress *** particular,the FLOA has not been observed in Ni because of its high stacking fault energy.

关键词： Cross-slip Molecular dynamics simulation Face-centered cubic metals Stacking fault energy