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Removal of perfluorinated surfactants from wastewater by adsorption and ion exchange--Influence of material properties,sorption mechanism and modeling

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Journal of Environmental Sciences 2017年第4期29卷 160-170页

作者： Falk Schuricht Ekaterina S.Borovinskaya Wladimir Reschetilowski institute of industrial Chemistry Dresden University of Technology

Perfluorooctane sulfonate（PFOS） has attracted increasing concern in recent years due to its world-wide distribution, persistence, bioaccumulation and potential toxicity. The influence of sorbent properties on the adsorptive elimination of PFOS from wastewater by activated carbons, polymer adsorbents and anion exchange resins was investigated with regard to their isotherms and kinetics. The batch and column tests were combined with physicochemical characterization methods, e.g., N2 physisorption, mercury porosimetry, infrared spectroscopy, differential scanning calorimetry, titrations, as well as modeling. Sorption kinetics was successfully modelled applying the linear driving force（LDF） approach for surface diffusion after introducing a load dependency of the mass transfer coefficient β*** big difference in the initial mass transfer coefficient βs,0, when non-functionalized adsorbents and ion-exchange resins are compared, suggests that the presence of functional groups impedes the intraparticle mass transport. The more functional groups a resin possesses and the longer the alkyl moieties are the bigger is the decrease in sorption *** the selectivity for PFOS sorption is increasing when the character of the functional groups becomes more hydrophobic. Accordingly, ion exchange and hydrophobic interaction were found to be involved in the sorption processes on resins, while PFOS is only physisorptively bound to activated carbons and polymer adsorbents. In agreement with the different adsorption mechanisms, resins possess higher total sorption capacities than adsorbents. Hence, the latter ones are rendered more effective in PFOS elimination at concentrations in the low μg/L range, due to a less pronounced convex curvature of the sorption isotherm in this concentration range.

关键词： PFOS Activated carbon Anion exchange resin Sorption kinetics modeling Sorption isotherm Selectivity of sorption

La_2Ce_2O_7 supported ruthenium as a robust catalyst for ammonia synthesis

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Journal of Rare Earths 2019年第5期37卷 492-499页

作者： Wenfeng Han Zhi Li Huazhang Liu institute of industrial Catalysis Zhejiang University of Technology

La_2Ce_2O_7 nanoparticles were prepared by citric acid complexation method followed by calcination at varied temperatures. Then, supported with 4 wt% Ru, they were evaluated as the catalysts for ammonia synthesis under conditions similar with industry. With La_2Ce_2O_7 being calcinated at 700 or 800℃, the experimental results indicate that the Ru/La_2Ce_2O_7 catalyst exhibits much higher ammonia concentration or ammonia synthesis rate than that of Ru/CeO_2 and Ru/La_2O_3. In addition, Ru/La_2Ce_2O_7 possesses high stability under over-heating test. In the absence of any promotor, ammonia concentration of Ru/La_2Ce_2O_7 catalyst approaches 14% at 450℃, GHSV of 10000 h^(-1) and pressure of 10 MPa. The rate-determining step of ammonia synthesis, dissociation of N_2 is significantly facilitated by the strong metalesupport interaction(SMSI) between Ru and La_2Ce_2O_7. Due to the interaction, La_2Ce_2O_7 tends to donate electrons to Ru,resulting in the high electron density over the surface of Ru active sites which is favorable for the dissociation of N_2. Consequently, high activity is achieved.

关键词： Ammonia synthesis Ruthenium La2Ce2O7 Activation energy Nanoparticles Rare earths

Study on Thermal Characteristics of a Novel Glass Curtain Wall System

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Journal of Thermal Science 2022年第6期31卷 1959-1969页

作者： FENG Chaoqing CHEN Xin’ge WANG Rui XU Zhao ZHANG Lizhuang YAN Suying College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot 010051China China National institute of standardization Beijing 100191China

In order to solve the conflict between indoor lighting and PV cells in building-integrated photovoltaic/thermal(BIPV/T) systems, a glass curtain wall system based on a tiny transmissive concentrator is proposed. This glass curtain wall has a direct influence on the heat transfer between indoor and outdoor, and the operating parameters of air and water inlet temperature, indoor and outdoor temperature, and radiation intensity have a significant influence on the heat transfer characteristics of the glass curtain wall. The 3D model is established by SoildWorks software, and the thermal characteristics of the new glass curtain wall system are simulated through computational fluid dynamics(CFD) method. Thermal performance was tested under actual weather for the winter working conditions. The CFD simulation results are verified by the test results under actual weather. The results show that thermal efficiency simulation results are in good agreement with the experimental results of the new glass curtain wall system. The simulation conditions were designed by using the orthogonal method, and the significance analysis of the influencing factors of the indoor wall surface heat gain was carried out. With the increase of the bottom heat flux and the air velocity, the heat absorption of the inner wall surface increases. When the wind speed is 0.1 m/s, the heat flow on the bottom surface rises from 500 W/m^(2) to 2500 W/m^(2), and the heat flow intensity on the interior wall changes from 10.31 W/m^(2) to -29.12 W/m^(2). Under typical working conditions, the new glass curtain wall system can reduce the indoor heat load by 47.5% than ordinary glass curtain wall.

关键词： glass curtain wall thermal characteristics orthogonal experimental design significant influencing factors

Eight new cytotoxic annonaceous acetogenins from the seeds of Annona squamosa

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Chinese Journal of Natural Medicines 2019年第4期17卷 291-297页

作者： MA Cheng-Yao LU Jia-Hui LI Xiang LIU Xiao CHEN Jian-Wei Pharmaceutical institute Nanjing University of Chinese Medicine Engineering Center of State Ministry of Education for standardization of Chinese Medicine Processing

Eight new annonaceous acetogenins, squamotin A–D(1–4), annosquatin IV–V(5 and 6), muricin O(7) and squamosten B(8), together with four known ones(9–12) were isolated from the seeds of Annona squamosa. Their structures were elucidated by chemical methods and spectral data. The inhibitory activities of compound 1–9 against three multidrug resistance cell lines were evaluated. All tested compounds showed strong cytotoxicity.

关键词： Annona squamosa Annonaceous acetogenins Cytotoxicity Multidrug resistance

An Addressing and Routing Scheme Based on Modified Euclidean Space for Hexagonal Networks

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China Communications 2015年第5期12卷 94-99页

作者： GONG Jiezhong LI Lin CHEN Gongliang WU Yue LI Jianhua Information Security Research Center China Electronics Standardization Institute Information Security Engineering School Shanghai Jiaotong University

The addressing and routing algorithm on hexagonal networks is still an open problem so *** many related works have been done to resolve this problem to some extent,the properties of hexagonal networks are still not explored *** this paper,we first create an oblique coordinate system and redefine the Euclidean space to address the hexagonal *** an optimal routing algorithm using vectors and angles of the redefined Euclidean space is *** with the traditional 3-directions scheme and the Cayley graph method,the proposed routing algorithm is more efficient and totally independent of the scale of networks with two-tuples *** also prove that the path(s) obtained by this algorithm is always the shortest one(s).

关键词： hexagonal network euclidean space addressing routing algorithm cayley graph

Dynamic Fracture of Ti-5553 Alloy in Taylor Impact Test

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Journal of Beijing institute of Technology 2017年第1期26卷 135-142页

作者： Denghui Zhao Qian Wang Lin Wang Maosheng Zhi School of Materials Science and Engineering National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing Institute of Technology Beijing 100081 China China Ordnance industrial standardization Research institute Beijing 100089 China Hubei Aerospace Vehicle Research institute Wuhan 430040 China

The dynamic fracture behavior of a new near-beta Ti-5Al-5Mo-5V-3Cr-1Fe（Ti-5553）alloy under a high strain rate loading was investigated systemically using the Taylor impact test,over the impact velocity ranging from156 ms-1 to 256 *** optical microscope（OM）and a scanning electron microscope（SEM）were used to characterize the microstructure *** experimental results have demonstrated that the velocity from deformation to fracture is 256 ms-1 for the alloy with anα＋βduplex microstructure including more primaryαphase,while the velocity is 234 ms-1 for the alloy with a duplex microstructure including less primaryα *** the impact fracture morphologies,smooth and smeared surfaces and ductile dimple areas can be *** failure mode of the titanium alloy with both microstructures is adiabatic shear *** to the fracture analysis,the ductile fracture area with the dimple area in the alloy with much more primaryαphase were more than that with less primaryα*** to the duplex microstructure with less primaryα phase,Ti-5553 alloy with more primaryαphase exhibited a better capability to resist an adiabatic shear damage.

关键词： Ti-5Al-5Mo-5V-3Cr-IFe Taylor impact test dynamic fracture behavior adiabatic shearband

Invariance of specific mass increment in the case of non-equilibrium growth

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Chinese Physics B 2015年第9期24卷 139-141页

作者： L.M.Martyushev A.P.Sergeev P.S.Terentiev Ural Federal University institute of industrial Ecology

The invariance of specific mass increments of crystalline structures that co-exist in the case of non-equilibrium growth is grounded for the first time by using the maximum entropy production principle. Based on the hypothesis of the existence of a universal growth equation, and through the dimensional analysis, an explicit form of the time-dependent specific mass increment is proposed. The applicability of the obtained results for describing growth in animate nature is discussed.

关键词： entropy production universal growth equation

Natural GmACO1 allelic variations confer drought tolerance and influence nodule formation in soybean

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aBIOTECH 2024年第3期5卷 351-355页

作者： Zhifang Zhang Junkui Ma Xia Yang Shan Liang Yucheng Liu Yaqin Yuan Qianjin Liang Yanting Shen Guoan Zhou Min Zhang Zhixi Tian Shulin Liu Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China The industrial Crop institute Shanxi Agricultural University/Shanxi Academy of Agricultural SciencesTaiyuan 030031China University of Chinese Academy of Sciences Beijing 100049China

Soybean[Glycine max(L.)Merr.]is one of the most important,but a drought-sensitive,*** the genes controlling drought tolerance is important in soybean ***,through a genome-wide association study,we identified one significant association locus,located on chromosome 8,which conferred drought tolerance variations in a natural soybean *** analysis and genetic validation demonstrated that GmACO1,encoding for a 1-aminocyclopropane-1-carboxylate oxidase,was the causal gene in this association locus,and positively regulated drought tolerance in ***,we determined that GmACO1 expression was reduced after rhizobial infection,and that GmACO1 negatively regulated soybean nodule ***,our findings provide insights into soybean cultivars for future breeding.

关键词： Soybean Drought tolerance GWAS Ethylene biosynthesis Nodule formation

THE CONVERGENCE OF TRUNCATED EULER-MARUYAMA METHOD FOR STOCHASTIC DIFFERENTIAL EQUATIONS WITH PIECEWISE CONTINUOUS ARGUMENTS UNDER GENERALIZED ONE-SIDED LIPSCHITZ CONDITION

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Journal of Computational Mathematics 2023年第4期41卷 663-682页

作者： Yidan Geng Minghui Song Mingzhu Liu School of Mathematics Harbin Institute of TechnologyHarbin 150001China Digital Technology Research Center China Electronics Standardization InstituteBeijing100007China

In this paper,we consider the stochastic differential equations with piecewise continuous arguments(SDEPCAs)in which the drift coefficient satisfies the generalized one-sided Lipschitz condition and the diffusion coefficient satisfies the linear growth *** the delay term t-[t]of SDEPCAs is not continuous and differentiable,the variable substitution method is not *** overcome this dificulty,we adopt new techniques to prove the boundedness of the exact solution and the numerical *** is proved that the truncated Euler-Maruyama method is strongly convergent to SDEPCAs in the sense of L'(q≥2).We obtain the convergence order with some additional *** example is presented to illustrate the analytical theory.

关键词： Stochastic differential equations Piecewise continuous argument One-sided Lipschitz condition Truncated Euler-Maruyama method