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Fouling of organic fractionation on ultrafiltration membrane for drinking water treatment:a case study

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Journal of Harbin Institute of technology(New Series) 2010年第6期17卷 819-823页

作者：康华何文杰刘秀红王东 School of municipal and Environmental Engineering Harbin Institute of Technology tianjin WaterWorks Group Company Ltd Beijing Drainage Group Co.Ltd Changchun Water Group Co.Ltd

The aim of this study was to obtain a better understanding of the range of organic molecular weight （MW） causing membrane fouling through the comparison between direct UF and in-line coagulation （without settling）/UF process. The experimental results indicated that, when raw water with organics was treated and the MW of more than half of the organics was less than 1 kDa, membrane fouling was rather serious by only UF and coagulation could improve the fouling for the treatment of raw water. Besides, coagulation/UF could remove organics in each region, and organics with MW greater than 30 kDa were the most possible matters causing membrane fouling, while organics with MW less than 1 kDa were in due to few organics removed. Therefore, organics with MW greater them brane foulingibly responsible for membrane fouling 30 kDa were the major factor of membrane fouling.

关键词： fouling molecular weight distribution organics Uhrafiltration

Neutralizing Antibody Responses against Five SARS-CoV-2 Variants and T Lymphocyte Change after Vaccine Breakthrough Infections from the SARS-CoV-2 Omicron BA.1 Variant in tianjin, China: A Prospective Study

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Biomedical and Environmental sciences 2023年第7期36卷 614-624页

作者： ZHANG Ying QU Jiang Wen ZHENG Min Na DING Ya Xing CHEN Wei YE Shao Dong LI Xiao Yan LI Yan Kun LIU Ying ZHU Di JIN Can Rui WANG LIN YANG Jin Ye ZHAI Yu WANG Er Qiang MENG Xing tianjin Center for Disease Control and Prevention Tianjin 300011China tianjin Key Laboratory of Pathogenic Microbiology of Infectious Disease Tianjin 300011China National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Sinovac Biotech Ltd Beijing 100085China

Objective To investigate whether Omicron BA.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity *** Blood samples were collected at two different time points from 124 Omicron BA.1 breakthrough infected patients and 124 controls matched for age,gender,and vaccination *** virus-neutralizing antibodies against five SARS-CoV-2 variants,including WT,Gamma,Beta,Delta,and Omicron BA.1,and T-lymphocyte lymphocyte counts in both groups were measured and statistically *** The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron BA.1 variant at 3 months after infection,but mainly increased the antibody level against the WT strain,and the antibody against the Omicron strain was the *** neutralizing antibody level decreased rapidly 6 months after *** T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 *** Omicron BA.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron *** antibodies against the different strains declined rapidly and showed features similar to those of ***,T-lymphocytes may play an important role in recovery.

关键词： SARS-CoV-2 COVID-19 Omicron BA.1 T cells Neutralizing antibodies

Homologous Comparisons of Photosynthetic System I Genes among Cyanobacteria and Chloroplasts

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Journal of Integrative Plant Biology 2008年第8期50卷 929-940页

作者： Jie Yu Pei-Jun Ma Ding-Ji Shi Shi-Ming Li Chang-Lu Wang School of Matin science & Engineering Tianjin University of Science & Technology Tianjin 300457 China Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

It has now believed that chloroplasts arose from cyanobacteria, however, during endosymbiosis, the photosynthetic genes in chloroplasts have been reduced. How these changes occurred during plant evolution was the focus of the present study. Beginning with photosystem I （PSI） genes, a homologous comparison of amino acid sequences of 18 subunits of PSI from 10 species of cyanobacteria, chloroplasts in 12 species of eucaryotic algae, and 28 species of plants （including bryophytes, pteridophytes, gymnospermae, dicotyledon and monocotyledon） was undertaken. The data showed that 18 genes of PSI can be divided into two groups： Part Ⅰ including seven genes （psaA, psaB, psaC, psal, psaJ, ycf3 and ycf4） shared both by cyanobacteria and plant chloroplasts; Part Ⅱ containing another 11 genes （psaD, psaE, psaF, psaK, psaL, psaM, btpA, ycf37, psaG, psaH and psaN） appeared to have diversified in different plant groups. Among Part Ⅰ genes, psaC, psaA and psaB had higher homology in all species of cyanobacteria and chloroplasts. Among Part Ⅱ genes, only psaG, psaH and psaN emerged in seed plants.

关键词： chloroplast cyanobacteria homologous comparison photosynthesis evolution PSI (photosystem I) genes

Enhanced methanation stability of nano-sized MoS2 catalysts by adding Al2O3

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Frontiers of Chemical science and Engineering 2015年第1期9卷 33-39页

作者： Zhenhua LI Jia HE Haiyang WANG Baowei WANG Xinbin MA Key Lab for Green Chemical technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

A series of unsupported MoS2 catalysts with or without Al2O3 modification was prepared using a modified thermal decomposition approach. The catalysts were tested for the methanation of carbon monoxide and the optimum one has 25.6wt-% Al2O3 content. The catalysts were characterized by nitrogen adsorption measurement, X-ray diffraction and transmission electron microscopy. The results show that adding appropriate amount of Al2O3 increases the dispersion of MoS2, and the increased interaction force between MoS2 and Al2O3 can inhibit the sintering of active MoS2 to some extent.

关键词： unsupported catalyst molybdenum sulfide,stability alumina methanation

MXene-based materials for electrochemical energy storage

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Journal of Energy Chemistry 2018年第1期27卷 73-85页

作者： Xu Zhang Zihe Zhang Zhen Zhou School of Materials science and Engineering National Institute for Advanced Materials Institute of New Energy Material Chemistry Collaborative Innovation Centre of Chemical Science and Engineering(Tianjin) Nankai University

Rechargeable batteries and supercapacitors are widely investigated as the most important electrochemical energy storage devices nowadays due to the booming energy demand for electric vehicles and hand-held electronics. The large surface-area-to-volume ratio and internal surface areas endow two-dimensional（2D） materials with high mobility and high energy density; therefore, 2D materials are very promising candidates for Li ion batteries and supercapacitors with comprehensive investigations. In 2011, a new kind of 2D transition metal carbides, nitrides and carbonitrides, MXene, were successfully obtained from MAX phases. Since then about 20 different kinds of MXene have been prepared. Other precursors besides MAX phases and even other methods such as chemical vapor deposition（CVD） were also applied to prepare MXene, opening new doors for the preparation of new MXene. Their 2D nature and good electronic properties ensure the inherent advantages as electrode materials for electrochemical energy storage. In this review, we summarize the recent progress in the development of MXene with emphasis on the applications to electrochemical energy storage. Also, future perspective and challenges of MXene-based materials are briefly discussed regrading electrochemical energy storage.

关键词： MXene2D materials Electrochemical energy storage Batteries Supercapacitors

An Analytical Solution for Nearshore Circulation Driven by Focused/Defocused Waves

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China Ocean Engineering 2019年第5期33卷 544-553页

作者： DING Yu-mei SHI Fengyan School of science Tianjin University of Science and Technology Tianjin 300475 China Center for Applied Coastal Research Department of Civil and Environmental Engineering University of Delaware Newark 19716 USA

An offshore shoal or bar refracts ocean surface waves and causes wave focusing/defocusing on the adjacent beach. Wave focal patterns characterized by alongshore variations in wave height, wave angle, and breaking location induce alongshore non-uniformities of wave setup and nearshore circulation, e.g., rip currents and alongshore currents, in the surfzone. A simplified analytic model for nearshore circulation generated by focused/defocused waves on a planar beach is developed and theoretical solutions are obtained using transport stream function and perturbations in alongshore distributions of wave height and wave angle at the breaker line. The analytic model suggests that alongshore currents are strongly affected by a pair of counter-rotating vortices generated shoreward of the wave focal zone. The vortices are persistent, and their strengths depend on the amplitudes of alongshore variations in wave height and wave angle. The alongshore gradient in wave height tends to intensify the vortices while the convergence of wave angle tends to weaken the vortices. Divergent flows associated with the vortices in the surfzone are intense, strengthening alongshore currents in the downstream of the wave focal zone and weakening alongshore currents or causing flows reversal in the upstream. Alongshore currents are modulated by rip currents associated with the wave focusing/defocusing patterns.

关键词： wave focusing and defocusing nearshore circulation rip current alongshore current analytical solution

Superelasticity of TiPdNi Alloys with and without Rare Earth Ce Addition

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Journal of Materials science & technology 2003年第2期19卷 179-182页

作者： Qingchao TIAN, Jiansheng WU and Yifeng CHENGKey Laboratory of the Ministry of Education for High Temperature Materials and Tests, School of Materials science and Engineering, Shanghai Jiao Tong Univ., Shanghai 200030, China Sch. of Mat. Sci. and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

Ti50.6Pd30Ni19.4 and Ti51Pd28Ni21 (Ce) alloys have been prepared under various temperatures for long time annealing. Differential scanning calorimetery (DSC), X-ray diffraction (XRD) and tensile test were employed to investigate the phase transformation behavior and superelasticity of the alloys. It has been found that the phase transformation temperature of Ti50.6Pd30Ni19.4 is about 40C higher than that of Ti51Pd28Ni21(Ce), and do not change much with different annealed temperature. Obvious superelasticity is retained in Ti50.6Pd30Ni19.4 alloy annealed at 400C for 18 h, and annealing at higher temperature shows a deterioration of this property. The Ce addition in TisiPd28Ni2i alloy significantly delays recrystallization, increases yied strength and elastic modulus, but the superelasticity is poor.

关键词： TiNi-Pd Shape memory alloy Superelasticity

Head-to-tail cyclization of a heptapeptide eliminates its cytotoxicity and significantly increases its inhibition effect on amyloid β-protein fibrillation and cytotoxicity

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Frontiers of Chemical science and Engineering 2018年第2期12卷 283-295页

作者： Shuai Ma Huan Zhang Xiaoyan Dong Linling Yu Jie Zheng Yan Sun Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300350 China Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA

Amyloid-β （Aβ） protein aggregation is the main hallmark of Alzheimer＇s disease （AD）. Inhibition of Aft fibrillation is thus a promising therapeutic approach to the prevention and treatment of AD. Recently, we designed a heptapeptide inhibitor, LVFFARK （LK7）. LK7 shows a promising inhibitory capability on Aft fibrillation, but is prone to self-assembling and displays high cytotoxicity, which would hinder its practical application. Herein, we modified LK7 by a head-to-tail cyclization and obtained a cyclic LK7 （cLK7）. cLK7 exhibits a different self-assembly behavior from LK7, and has higher stability against proteolysis than LK7 and little cytotoxicity to SH-SY5Y cells. Thermodynamic analysis revealed that both LK7 and cLK7 could bind to Aβ40 by electrostatic interactions, hydrogen bonding and hydrophobic interactions, but the binding affinity of cLK7 for Afl40 （KD = 4.96 μmol/L） is six times higher than that of LK7 （KD = 32.2 μmol/L）. The strong binding enables cLK7 to stabilize the secondary structure of Aβ40 and potently inhibit its nucleation, fibrillation and cytotoxicity at extensive concentration range, whereas LK7 could only moderately inhibit Aβ40 fibrillation and cytotoxicity at low concentrations. The findings indicate that the peptide cyclization is a promising approach to enhance the performance of peptide-based amyloid inhibitors.

关键词： Alzheimer's disease amyloid β-protein cyc-lic peptide inhibition protein aggregation

Cu(Ⅱ) and Ni(Ⅱ) Complexes with 5,5'-Bis(2-acylphenyl)diazo-dipyrromethane:Syntheses,Structures and Properties

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Chinese Journal of Structural Chemistry 2015年第12期34卷 1876-1882页

作者：张慧陈金环尹振明 College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional Molecule Tianjin Normal University Key Laboratory of Inorganic-organic Hybrid Functional Material Chemistry (tianjin Normal University) Ministry of Education Tianjin Normal University

The reactions of 5,5＇-bis（2-acylphenyl）diazo-dipyrromethane （H2L） with CuSO4 and NiCl2 resulted in the formation of corresponding mononuclear coordination complexes 2 （CuL） and 3 （NIL）. The crystal of complex 2 is of monoclinic system, space group P21 with a = 10.040（5）, b = 11.900（5）, c = 11.170（5） A, β = 93.057（8）°, V = 1332.8（2） A3, Z = 2, C29H28N602Cu, Mr = 556.11, Dc = 1.386 g/cm, F（000） = 578 and/z（MoKa） = 0.857 mm^-1. The crystal of complex 3 belongs to the monoclinic system, space group P21/n with a = 12.0445（6）, b = 17.2101（8）, c = 16.3304（6） A, β = 128.407（2）°, V = 2654.6（2） A3, Z = 4, C29H28N6O2Ni, Mr= 551.28, Dc= 1.380 g/cm, F（000） = 1152 and μ（MoKa） = 0.770 mm^-1. In both complexes, the metal ions are in square-planar geometry by coordinating to two azo N atoms and two deprotonated pyrrole N atoms. Intramolecular Cu…O=C in complex 2 and intermolecular Ni…O=C in complex 3 were found. The UV-Vis spectra and thermal stability of complexes 2 and 3 were also studied.

关键词： 5,5'-bis(2-acylphenyl)diazo-dipyrromethane metal complexes structures properties