Bayer Technology and Engineering Shanghai Co.

Shanghai, China

Bayer Technology and Engineering Shanghai Co.

Shanghai, China
Time filter
Source Type

Xu J.,Wenzhou University | Zhu L.,Wenzhou University | Xu G.,Bayer Technology and Engineering Shanghai Co. | Yu W.,Wenzhou University | Ray A.K.,University of Western Ontario
Journal of Chromatography A | Year: 2013

Precise determination of competitive adsorption isotherm is of great importance for model-based optimization and scale-up of chromatographic separation processes, particularly for the simulated moving bed (SMB) systems due to its intrinsic complexity. In this study, five parameters of a bi-Langmuir model for adsorption of ketoprofen enantiomers on a preparative Chiralpak AD column at 25. °C were determined by the application of inverse method (IM). Transport-dispersive (TD) model parameters, axial dispersion and mass transfer coefficients were independently estimated first by tuning a series of linear pulse experiments. Competitive adsorption isotherm model parameters were then determined independently by fitting the experimental data. A new numerical scheme that couples non-dominated sorting genetic algorithm (NSGA) and Levenberg-Marquardt algorithm (LMA) was proposed for the data fitting. NSGA was capable of rapidly locating the optimal solution in the parametric space while LGA allowed speedy convergence given a good initial guess. Independently measured band profiles and simulated moving bed (SMB) experiments were later used to validate the model parameters. The experimental results were in good agreement with the model predictions. © 2012 Elsevier B.V.

Wang Y.-J.,Fujian New Wuhuan Engineering Design Co. | Zhu H.-S.,Bayer Technology and Engineering Shanghai Co. | Zhai J.-G.,Shanghai Research Institute of Chemical Industry
Petrochemical Equipment | Year: 2015

The theory background for prevention of brittle fracture in ASME VIII-1 - 2013 is introduced. The requirements for impact test exemption curves, impact test energy value, low stress service and loading rate are analyzed and discussed also. © 2015, Lanzhou Petroleum Machinery Research Institute. All rights reserved.

Cheng X.,Bayer Technology and Engineering Shanghai Co.. | Cheng R.,Wenzhou Medical College | Ou S.,Tongji University | Li Y.,Tongji University
Carbohydrate Polymers | Year: 2013

The design of chelating polymers with fast complexation of the metal ions is particularly interest. In this work, the dithiocarbamate-modified glycidyl methacrylate starch was synthesized and characterized by FT-IR, 13C NMR and XRD spectra. Its sorption performance for heavy metals fixation was studied. It was found that the removal process of metal ions involved a fast increase stage followed by a slower stage. There was a higher match between the pseudo-second-order equation and the experimental data. The sorption rate constants were related to the substitution rates of hydrated metal ions in aqueous solutions, showing typical chemisorption. The Langmuir isotherm gave satisfying fits to equilibrium data of metals adsorption. And the capacities followed the sequence Cu2+ > Cd2+ > Co2+ > Zn2+ > Ni2+ > Mn2+, which could be well demonstrated with chelating interaction caused by sulfur atoms. Such understanding provides new insights as how to synthesize and use the dithiocarbamate-based polysaccharides. © 2013 Elsevier Ltd. All rights reserved.

Zhu H.,Bayer Technology and Engineering Shanghai Co. | Zhai J.,Shanghai Research Institute of Chemical Industry | Wang H.,Nanjing University of Technology | Zheng Y.,Inspection Institute of Jiangsu Province
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2016

The stress analysis method for fixed tubesheet (TS) heat exchangers (HEX) in pressure vessel codes such as ASME VIII-1, EN13445, and GB151 all assume a geometric and loading plane of symmetry at the midway between the two TSs so that only half of the unit or one TS is need to be considered. In this study, the midplane symmetry assumption is discarded. More common situations are considered such as unequal TS thickness, different edge conditions, pressure drop, and dead weight on two TSs. Based on the classical thin plate and shell theoretical solution, an analytical method of stress analysis for TS is presented. The proposed method is suitable for different types of HEX due to fewer assumptions employed in this study. Analysis shows that floating and U-tube HEX are the two special cases of the proposed method. Theoretical comparison shows that ASME method can be obtained from the special case of the simplified mechanical model of the proposed method. Typical geometries and loading are considered, and the proposed method is used to check the adequacy of design. Predictions are compared with the results obtained from axisymmetric finite element analysis (FEA) and current ASME method. Comparison results indicate that predictions given by this paper agree well with FEA while ASME results are not correct or not accurate. Copyright © 2016 by ASME.

Yuan Y.,Yangzhou University | Zhu H.,Yangzhou University | Zhao D.,Bayer Technology and Engineering Shanghai Co. | Zhang L.,Yangzhou University
Synthesis | Year: 2011

The catalytic Sonogashira coupling reaction of terminal alkynes and aryl halides is developed using copper(II) oxide nanoparticles as catalyst in dimethyl sulfoxide. The procedure is experimentally simple, general, efficient, and free from addition of external cocatalysts or chelating ligands. © Georg Thieme Verlag Stuttgart - New York.

Zhao D.,Bayer Technology and Engineering Shanghai Co. | Ding K.,CAS Shanghai Institute of Organic Chemistry
ACS Catalysis | Year: 2013

Asymmetric catalysis in flow has been attracting much attention very recently because of the potential advantages over its batchwise counterpart, such as high-throughput screening and synthesis, easy automation with the integration of on-demand reaction analysis, little or no reaction workup, and potential long-term use of the catalysts in the case of heterogeneous catalysis. Homogeneous asymmetric catalysis performed in a microreactor has demonstrated successful examples in fast catalyst screening, integrated inline/ onlineanalysis, microflow photocatalysis, multistep transformation with unstable intermediates, and potential for lower catalyst loading or homogeneous catalyst recylcing. Since heterogeneous asymmetric catalysis serves as a better way than its homogeneous analogue for catalyst separation and recycling, this Review Article summarizes recent development via different catalyst immobilization methods, such as covalent support, a self-supported method, an adsorption method, and H-bonding, electrostatic or ionic interaction, and nonconventional media, as well. In addition, biocatalysis, including enzyme-catalyzed kinetic resolution and transformation, in flow will be discussed either in homogeneous or heterogeneous mode. © 2013 American Chemical Society.

Yuan Y.,Yangzhou University | Ji X.,Yangzhou University | Zhao D.,Bayer Technology and Engineering Shanghai Co.
European Journal of Organic Chemistry | Year: 2010

Quaternary ammonium iodide, a metal-free and mild catalyst, was proven to be a successful catalyst in the oxidative cleavage of 1,3-dicarbonyl derivatives with H 2O 2 as terminal oxidant. The mechanistic aspects of these "multistep" catalytic oxidations were discussed in terms of the catalytic cycle of the iodine species and the oxidative cleavage of the α carbon from the dicarbonyl compounds to generate the corresponding carboxylic acids. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mleczko L.,Bayer AG | Zhao D.,Bayer Technology and Engineering Shanghai Co.
ACS Symposium Series | Year: 2014

This chapter introduces the concepts of flow technology primarily in relationship to the use of organolithium reagents and reactions, and describe a workflow for flow chemistry and micro-reaction technology along with the necessary infrastructure with suitable equipment at different scales for the lithiation of chloroarenes. This work highlights the many advantages of flow chemistry in transferring a potentially hazardous laboratory scale reaction into a viable large scale operation. In all aspects, continuous lithiation of fluoroaromatics was superior to the corresponding batch processes. © 2014 American Chemical Society.

Fu M.,East China University of Science and Technology | Fu M.,Bayer Technology and Engineering Shanghai Co. | Luan W.,East China University of Science and Technology | Tu S.-T.,East China University of Science and Technology | Mleczko L.,Bayer AG
Journal of Nanomaterials | Year: 2015

Highly photoluminescent core/shell CuInS2/ZnS (CIS/ZnS) nanocrystals were synthesized. Zinc acetate and dodecanethiol in octadecene solvent were used for shell growth. The structure and composition of QDs were investigated with inductively coupled plasma-optical emission spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The crystal phase of CIS was tetragonal chalcopyrite. Based on X-ray diffraction analysis, it has been concluded that the growth of the ZnS shell did not affect the phase structure of CuInS2 (CIS). Photoluminescence (PL) quantum yield (QY) of CIS increased to 80% after epitaxial growth of ZnS, and the PL emission wavelength can be feasibly tuned to be in the range of 560-710 nm by adjusting shell growth time. The superb photostability with high PL QY of CIS/ZnS nanocrystals is ascribed to the gradient of the chemical composition that has been formed between the core and the shell. © 2015 Min Fu et al.

Zhao D.,Bayer Technology and Engineering Shanghai Co.
Chinese Journal of Organic Chemistry | Year: 2013

As a further-developing process intensification technology, flow chemistry has achieved a striking development either in academic or industrial area in the past decade. Updated applications of flow chemistry in pharmaceutical synthesis are overviewed. Compared with its early research and development (R&D), current flow chemistry has already shown a lot of breakthroughs. For instance, no more limitations to the proof of feasibility concept for some certain reaction, public development of this technology by more and more distinguished international pharmaceutical companies and quite a few corresponding reports of successful examples about multistep total synthesis of active pharmaceutical ingredients (APIs). Different process categorizations are emphasized with many API syntheses to demonstrate the up-to-date progress of this topic, after a brief introduction of the advantages, existing challenges and the corresponding solutions for flow chemistry. © 2013 Chinese Chemical Society & SIOC, CAS.

Loading Bayer Technology and Engineering Shanghai Co. collaborators
Loading Bayer Technology and Engineering Shanghai Co. collaborators