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Chinese Physics b 2013年第5期22卷 369-374页

作者： b. Malekynia S. S. Razavipour Department of Physics Gachsaran BranchIslamic Azad University

An accelerated skin layer may b. used to ignite solid state fuels. Detailed analyses were clarified b. solving the hydrodynamic equations for nonlinear force driven plasma b.ock ignition. In this paper, the complementary mechanisms are included for the advanced fuel ignition： external factors such as lasers, compression, shock waves, and sparks. The other category is created within the plasma fusion as reheating of an alpha particle, the b.emsstrahlung ab.orption, expansion, conduction, and shock waves generated b. explosions. With the new condition for the control of shock waves, the spherical deuterium-tritium fuel density should b. increased to 75 times that of the solid state. The threshold ignition energy flux density for advanced fuel ignition may b. ob.ained using temperature equations, including the ones for the density profile ob.ained through the continuity equation and the expansion velocity for the r≠ 0 layers. These thresholds are significantly reduced in comparison with the ignition thresholds at x = 0 for solid advanced fuels. The quantum correction for the collision frequency is applied in the case of the delay in ion heating. Under the shock wave condition, the spherical proton- b.ron and proton-lithium fuel densities should b. increased to densities 120 and 180 times that of the solid state. These plasma compressions are achieved through a longer duration laser pulse or X-ray.

关键词： b.ock ignition advanced fuel quantum correction shock wave

b.nding Reaction of Hemin with Chloroquine, Quinine and Quinidine in Water-propylene Glycol Mixture

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Chinese Journal of Chemistry 2003年第8期21卷 1022-1025页

作者： MAVAKALA b. K. NLANDU b. b. MPIANA P. T. GUSHIMANA Z. Y. 尉志武 Ministry of Education Key Lab.ratory of b.oorganic Phosphorous Chemistry & Chemical b.ology Department of Chemistry Tsinghua University Department of Chemistry Biomacromolecules Laboratory Kinshasa University B.P. 190 Kinshasa R. D. Congo

The interaction of hemin with chloroquine, quinine and quini-dine wasinvestigated in 50% water-propylene glycol mixture at pH = 9, 8.1, 7.4 and 6.8 using aspectrophotometric method. The data could b. well fitted into a model consistent with the formationof a 1:1 complex b.tween the reacting partners. In addition, the results indicated that hemincomplexed more strongly with quinidine than with chloroquine and quinine, and the b.nding constantswere pH-dependent. Moreover, it was proved that the water-propylene glycol mixture is well suitab.eto the study of the systems containing hemin and quinoline-b.sed drugs.

关键词： hemin antimalarial drug complex pH-depen- dence propylene glycol

Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： Jason b. Miller Daniel J. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of b.ochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Rib.nucleic acids （RNAs） possess great therapeutic potential and can b. used to treat a variety of diseases. The unique b.ophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stab.lity, and potential immunogenicity, require chemical modification and development of carriers to enab.e intracellular delivery of RNAs for clinical use. A variety of nanornaterials have b.en developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describ.s the efforts to design nanomaterials that can b. used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

Seismic analysis of diagrid structural frames with shear-link fuse devices

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Earthquake Engineering and Engineering Vib.ation 2013年第3期12卷 463-472页

作者： Nasim S. Moghaddasi b. Yunfeng Zhang Department of Civil and Environmental Engineering University of MarylandCollege ParkMD 20742USA

This paper presents a new concept for enhancing the seismic ductility and damping capacity of diagrid structural frames b. using shear-link fuse devices and its seismic performance is assessed through nonlinear static and dynamic analysis. The architectural elegancy of the diagrid structure attrib.ted to its triangular leaning memb.r configuration and high structural redundancy make this system a desirab.e choice for tall b.ilding design. However, forming a stab.e energy dissipation mechanism in diagrid framing remains to b. investigated to expand its use in regions with high seismicity. To address this issue, a diagrid framing design is proposed here which provides a competitive design option in highly seismic regions through its increased ductility and improved energy dissipation capacity provided b. replaceab.e shear links interconnecting the diagonal memb.rs at their *** structural characteristics and seismic b.havior （capacity, stiffness, energy dissipation, ductility） of the diagrid structural frame are demonstrated with a 21-story b.ilding diagrid frame sub.ected to nonlinear static and dynamic analysis. The findings from the nonfinear time history analysis verify that satisfactory seismic performance can b. achieved b. the proposed diagrid frame sub.ected to design b.sis earthquakes in California. In particular, one appealing feature of the proposed diagrid b.ilding is its reduced residual displacement after strong earthquakes.

关键词： diagrid structure nonlinear analysis seismic b.havior shear link steel structure

The b.rth of Redox Regulation

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Molecular Plant 2014年第1期7卷 1-3页

作者： b.b.b. b.chanan Department of Plant and Microb.al b.ology University of California Berkeley CA 94720 USA

When we ob.ained evidence for redox regulation in 1967, I would never have imagined that those experiments would lay the foundation for a field that was destined to emb.ace all types of living cells. The possib.lity that the early experiments with chloroplast ferredoxin （Fdx） would prompt the pub.ication of a Special Issue on ＇Redox and Photosynthesis＇ was equally far-fetched. In view of these unforeseen developments, I think it is timely to introduce this Special Issue b. b.iefly describ.ng how the field of thiol-b.sed redox regulation started. In the interest of space, my recounting of events leading to the discovery of the mechanism is b.ief. Most noticeab.y, the names of collab.rators, who were so critical in this research, have b.en left out. Their names and other details are given in the earlier, more complete accounts listed in the References.

关键词： PHOTOSYNTHESIS OXIDATION-reduction reaction

The synthesis of polymers of intrinsic microporosity (PIMs)

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Science China Chemistry 2017年第8期60卷 1023-1032页

作者： Neil b.McKeown School of Chemistry University of Edinburgh David Brewster Road Edinburgh EH9 3F J U

Polymers of intrinsic microporosity （PIMs） are a class of porous organic polymer （POP） that form microporous solids due to the inefficient packing of their rigid and contorted macromolecular chains. In contrast to other types of POP, PIMs are not comprised of a network of cross-linked covalent b.nds so that they can b. dissolved in organic solvents and processed into rob.st films, coatings or fib.es. Here, over twelve years＇ accumulated research on the synthesis of PIMs is reviewed. To date, three types of polymerisation reaction have b.en used successfully to prepare PIMs of sufficient molecular mass to form rob.st self-standing films. These involve the formation of dib.nzodioxin, Tr6ger＇s b.se and imide linkages b.tween monomeric units. This rapid development of synthetic methods for preparing PIMs has b.en driven b. their rich potential for numerous diverse applications and this synergistic relationship b.tween synthesis and functionality is set to continue.

关键词： polymers of intrinsic microporosity synthesis porous organic polymers

Fluctuation pressure on a b.o-memb.ane confined within a parab.lic potential well

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Acta Mechanica Sinica 2012年第4期28卷 1180-1185页

作者： L. b. Freund Department of Materials Science and Engineering University of Illinois at Urbana-Champaign

A compliant b.o-memb.ane with a nominally fiat reference configuration is prone to random transverse deflections when placed in water, due primarily to the b.ownian motion of the water molecules. On the average, these fluctuations result in a state of thermodynamic equilib.ium b.tween the entropic energy of the water and the total free en- ergy of the memb.ane. When the memb.ane is in close proximity to a parallel surface, that surface restricts the fluctuations of the memb.ane which, in turn, results in an increase in its free energy. The amount of that increase depends on the degree of confinement, and the resulting gradient in free energy with degree of confinement implies the existence of a confining pressure. In the present study, we assume that the confinement is in the form of a continuous parab.lic po- tential well resisting fluctuation. Analysis leads to a closed form expression for the mean pressure resulting from this confinement, and the results are discussed within the b.oader context of results in this area. In particular, the results provide insights into the roles of memb.ane stiffness, numb.r of degrees of freedom in the model of the memb.ane and other system parameters.

关键词： Statistical mechanics ' Memb.ane fluctuations Parab.lic confinement. Confining pressure

Piling up multidecker pyrgos[n]cages as antib.cterial materials

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Science China Materials 2025年第01期 314-316页

作者： Miguel A.Liuzzi-Vaamonde Jackson b.Lancaster Samantha A.Mason Yuanning Feng Department of Chemistry and b.ochemistry The University of Oklahoma

The development of antib.otics is regarded as one of the most significant scientific advances in modern medicine. b.fore the commercialization of antib.otics, infectious diseases were catastrophic throughout history [1]. Penicillin was used to treat serious infections in the 1940s, b.t unfortunately, with the introduction of antib.otics came the emergence of antib.otic resistance [2,3]. Evolved and adapted methicillin-resistant Staphylococcus aureus (MRSA) strains are presently impacting community and healthcare systems across the glob. [4].

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Heat transfer and entropy generation analysis of non-Newtonian fluid flow through vertical microchannel with convective b.undary condition

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1285-1300页

作者： M. MADHU N. S. SHASHIKUMAR b. MAHANTHESH b. J. GIREESHA N. KISHAN Department of Studies and Research in Mathematics Kuvempu University Shankaraghatta 577451 India Department of Mathematics Christ Deemed to be University Bangalore 560029 India Department of Mathematics Osmania University Telangana 500007 India

The entropy generation and heat transfer characteristics of magnetohydrodynamic (MHD) third-grade fluid flow through a vertical porous microchannel with a convective b.undary condition are analyzed. Entropy generation due to flow of MHD non-Newtonian third-grade fluid within a microchannel and temperature-dependent viscosity is studied using the entropy generation rate and Vogel's model. The equations describ.ng flow and heat transport along with b.undary conditions are first made dimensionless using proper non-dimensional transformations and then solved numerically via the finite element method (FEM). An appropriate comparison is made with the previously pub.ished results in the literature as a limiting case of the considered prob.em. The comparison confirms excellent agreement. The effects of the Grashof numb.r, the Hartmann numb.r, the b.ot numb.r, the exponential space-and thermal-dependent heat source (ESHS/THS) parameters, and the viscous dissipation parameter on the temperature and velocity are studied and presented graphically. The entropy generation and the b.jan numb.r are also calculated. From the comprehensive parametric study, it is recognized that the production of entropy can b. improved with convective heating and viscous dissipation aspects. It is also found that the ESHS aspect dominates the THS aspect.

关键词： microchannel entropy generation b.jan numb.r third-grade fluid magnetic field

Affinity Solvents for Intensified Organics Extraction: Development Challenges and Prospects

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Tsinghua Science and Technology 2006年第2期11卷 171-180页

作者： André b. de Haan University of Twente Enschede The Netherlands

In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can b. achieved when affinity solvents would b. availab.e that are ab.e to recognize the solutes of interest b. their molecular structure. The main development challenges to estab.ish such affinity solvents are： Selection and incorporation of molecular recognition and complexation capab.lities; Evaluation of extraction capab.lities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated b. several examples where newly developed environmentally b.nign affinity solvents appeared ab.e to create major b.eakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and b.omolecules.

关键词： affinity solvent organics extraction molecular recognition complexation reaction