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Tianjin, China

Tianjin University is a national university under the direct administration of the Ministry of Education of China. It is the first modern higher education institution in China. It was established in 1895 as Tientsin University/Imperial Tientsin University and later Peiyang University . In 1951, after restructuring, it was renamed Tianjin University, and became one of the largest multidisciplinary engineering universities in China. The university was one of the first 16 universities accredited by the State in 1959. It is also among the first group of institutions of higher learning in the national “211-Project” to which priority is given in construction. In order to carry out the “21st Century Education Revitalizing Action Plan”, in late 2000 the Ministry of Education and Tianjin Municipality signed an agreement which aims to build Tianjin University into a world famous university in the 21st Century. Wikipedia.

Jiao K.,University of Waterloo | Li X.,University of Waterloo | Li X.,Tianjin University
Progress in Energy and Combustion Science | Year: 2011

Polymer electrolyte membrane fuel cell (PEMFC) has been recognized as a promising zero-emission power source for portable, mobile and stationary applications. To simultaneously ensure high membrane proton conductivity and sufficient reactant delivery to reaction sites, water management has become one of the most important issues for PEMFC commercialization, and proper water management requires good understanding of water transport in different components of PEMFC. In this paper, previous researches related to water transport in PEMFC are comprehensively reviewed. The state and transport mechanism of water in different components are elaborated in detail. Based on the literature review, it is found that experimental techniques have been developed to predict distributions of water, gas species, temperature and other parameters in PEMFC. However, difficulties still remain for simultaneous measurements of multiple parameters, and the cell and system design modifications required by measurements need to be minimized. Previous modeling work on water transport in PEMFC involves developing rule-based and first-principle-based models, and first-principle-based models involve multi-scale methods from atomistic to full cell levels. Different models have been adopted for different purposes and they all together can provide a comprehensive view of water transport in PEMFC. With the development of computational power, application of lower length scale methods to higher length scales for more accurate and comprehensive results is feasible in the future. Researches related to cold start (startup from subzero temperatures) and high temperature PEMFC (HT-PEMFC) (operating at the temperatures higher than 100 °C) are also reviewed. Ice formation that hinders reactant delivery and damages cell materials is the major issue for PEMFC cold start, and enhancing water absorption by membrane electrolyte and external heating have been identified as the most effective ways to reduce ice formation and accelerate temperature increment. HT-PEMFC that can operate without liquid water formation and membrane hydration greatly simplifies water management strategy, and promising performance of HT-PEMFC has been demonstrated. © 2010 Elsevier Ltd. All rights reserved.

Precise DNA replication is critical for the maintenance of genetic integrity in all organisms. In all three domains of life, DNA replication starts at a specialized locus, termed as the replication origin, oriC or ORI, and its identification is vital to understanding the complex replication process. In bacteria and eukaryotes, replication initiates from single and multiple origins, respectively, while archaea can adopt either of the two modes. The Z-curve method has been successfully used to identify replication origins in genomes of various species, including multiple oriCs in some archaea. Based on the Z-curve method and comparative genomics analysis, we have developed a web-based system, Ori-Finder, for finding oriCs in bacterial genomes with high accuracy. Predicted oriC regions in bacterial genomes are organized into an online database, DoriC. Recently, archaeal oriC regions identified by both in vivo and in silico methods have also been included in the database. Here, we summarize the recent advances of in silico prediction of oriCs in bacterial and archaeal genomes using the Z-curve based method. © 2014 Bentham Science Publishers.

A simple, rapid, and sensitive method for visual detection of sequence-specific DNA was developed using hairpin DNA as the recognition element and hydroxylamine-enlarged gold nanoparticles (Au-NPs) as the signal producing component. In the assay, we employed a hairpin DNA probe dually labeled with amine and biotin at the 5'- and 3'-end, respectively. The probe was coupled with reactive N-oxysuccinnimide in a DNA-bind 96-well plate. Without the target DNA, the immobilized hairpin probe was in a "closed" state, which kept the streptavidin-gold off the biotin. The hybridization between the loop sequence and the target broke the short stem duplex upon approaching the target DNA. Consequently, biotin was forced away from the 96-well plate surface and available for conjugation with the streptavidin-gold. The hybridization could be detected visually after the HAuCl(4)-NH(2)OH redox reaction catalyzed by the Au-NPs. Under the optimized conditions, the visual DNA sensor could detect as low as 100 amol of DNA targets with excellent differentiation ability and even a single-base mismatch.

Zhang C.-T.,Tianjin University
PLoS ONE | Year: 2013

Background: Although being a simple and effective index that has been widely used to evaluate academic output of scientists, the h-index suffers from drawbacks. One critical disadvantage is that only h-squared citations can be inferred from the h-index, which completely ignores excess and h-tail citations, leading to unfair and inaccurate evaluations in many cases. Methodology/Principal Findings: To solve this problem, I propose the h'-index, in which h-squared, excess and h-tail citations are all considered. Based on the citation data of the 100 most prolific economists, comparing to h-index, the h'-index shows better correlation with indices of total-citation number and citations per publication, which, although relatively reliable and widely used, do not carry the information of the citation distribution. In contrast, the h'-index possesses the ability to discriminate the shapes of citation distributions, thus leading to more accurate evaluation. Conclusions/Significance: The h'-index improves the h-index, as well as indices of total-citation number and citations per publication, by possessing the ability to discriminate shapes of citation distribution, thus making the h'-index a better single-number index for evaluating scientific output in a way that is fairer and more reasonable. © 2013 Chun-Ting Zhang.

Du J.,Tianjin University
Physica A: Statistical Mechanics and its Applications | Year: 2012

Transition state theory (TST) is generalized to nonequilibrium systems with power-law distributions. The stochastic dynamics that gives rise to the power-law distributions for the reaction coordinate and momentum is modeled by Langevin equations and corresponding FokkerPlanck equations. It is considered that a system far away from equilibrium does not have to relax to a thermal equilibrium state with BoltzmannGibbs distribution, but asymptotically approaches a nonequilibrium stationary state with a power-law distribution. Thus, we obtain a possible generalization of TST rates to nonequilibrium systems with power-law distributions. Furthermore, we derive the generalized TST rate constants for one-dimensional and n-dimensional Hamiltonian systems away from equilibrium, and obtain a generalized Arrhenius rate for systems with power-law distributions. © 2011 Elsevier B.V. All rights reserved.

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