The Experts below are selected from a list of 157452 Experts worldwide ranked by ideXlab platform
Zuo Baoqi - One of the best experts on this subject based on the ideXlab platform.
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Green Process to prepare water-insoluble silk scaffolds with silk I structure
International journal of biological macromolecules, 2018Co-Authors: Zhang Zhengshi, Ding Zhaozhao, Huang Ji-wei, Qin Jianzhong, Shen Yixin, Zhang Feng, Zuo BaoqiAbstract:Abstract Silk porous scaffolds have shown promising applications in tissue regenerations as cellular scaffolds to incorporate cells in vitro and in vivo , and facilitate cell proliferation and production of extracellular matrix. It remains strong needs to optimize the microstructures and performances of silk scaffolds for better biocompatibility. Here, a Green Process was developed to form water-insoluble scaffolds. Repeated freezing-dissolving procedures and silk nanofibers were introduced to tune the performances of the scaffolds, resulting in amorphous conformations and nanofibrous structures. Controllable degradation and mechanical properties as well as improved cell compatibility were then achieved for these scaffolds, suggesting their promising future in tissue regenerations. Our present results confirmed the possibility of actively designing silk scaffolds with preferable properties used in various tissue regenerations.
David L. Kaplan - One of the best experts on this subject based on the ideXlab platform.
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Green Process to prepare silk fibroin/gelatin biomaterial scaffolds.
Macromolecular bioscience, 2010Co-Authors: Xiaohui Zhang, David L. KaplanAbstract:A new all-aqueous and Green Process is described to form three-dimensional porous silk fibroin matrices with control of structural and morphological features. Silk-based scaffolds are prepared using lyophilization. Gelatin is added to the aqueous silk fibroin solution to change the silk fibroin conformation and silk fibroin-water interactions through adjusting the hydrophilic interactions in silk fibroin-gelatin-water systems to restrain the formation of separate sheet like structures in the material, resulting in a more homogenous structure. Water annealing is used to generate insolubility in the silk fibroin-gelatin scaffold system, thereby avoiding the use of organic solvents such as methanol to lock in the beta-sheet structure. The adjusting of the concentration of gelatin, as well as the concentration of silk fibroin, leads to control of morphological and functional properties of the scaffolds. The scaffolds were homogeneous in terms of interconnected pores, with pore sizes ranging from 100 to 600 microm, depending on the concentration of silk fibroin used in the Process. At the same time, the morphology of the scaffolds changed from lamellar sheets to porous structures based on the increase in gelatin content. Compared with salt-leaching aqueous-derived scaffolds and hexafluoroisopropanol (HFIP)-derived scaffolds, these freeze-dried scaffolds had a lower content of beta-sheet, resulting in more hydrophilic features. Most of gelatin was entrapped in the silk fibroin-gelatin scaffolds, without the burst release in PBS solution. During in vitro cell culture, these silk fibroin-gelatin scaffolds had improved cell-compatibility than salt-leaching silk fibroin scaffolds. This new Process provides useful silk fibroin-based scaffold systems for use in tissue engineering. Furthermore, the whole Process is Green, including all-aqueous, room temperature and pressure, and without the use of toxic chemicals or solvents, offering new ways to load bioactive drugs or growth factors into the Process.
Ming-jer Lee - One of the best experts on this subject based on the ideXlab platform.
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A Green Process for recovery of 1-propanol/2-propanol from their aqueous solutions: Experimental and MD simulation studies
The Journal of Chemical Thermodynamics, 2017Co-Authors: Bhupender S. Gupta, Mohamed Taha, Ming-jer LeeAbstract:Abstract In the present study, we have found that a common and relatively inexpensive biological buffer tris(hydroxymethyl)aminomethane (TRIS) is potentially applicable to shift the azeotrope compositions of aqueous solutions of 1-propanol and 2-propanol. By taking the advantage of our findings, we are proposing a Green Process for the recovery of these organics from their respective aqueous solutions. In order to confirm the effect of TRIS buffer on vapor–liquid equilibrium behavior of the aqueous propanol systems, we measured the isobaric vapor–liquid equilibrium (VLE) data at 101.3 kPa for the 1-proponol + water + TRIS and 2-propanol + water + TRIS systems over the azeotropic range with various concentrations of TRIS (0.02, 0.04, 0.08, and 0.12 in mole fraction). The binary interaction parameters were obtained for TRIS with water, TRIS with 1-propanol, and TRIS with 2-propanol by correlating the new VLE data with the NRTL model. The isobaric VLE properties for the investigated propanol + water mixtures in the presence of various concentrations of TRIS were also predicted with the conductor-like screening model COSMO-RS. Based on the predicted excess molar enthalpies (HEm) from the COSMO-RS, the interactions between all constituent pairs of molecules were estimated. To explore the mechanism of TRIS-based separation of 1-propanol/2-propanol from their aqueous solutions, the interactions between different pairs of molecules were also investigated by using fluorescence analysis and Molecular Dynamic (MD) simulation. In comparison with the conventional corrosive inorganic salts and volatile organic entrainers, TRIS is non-corrosive, non-volatile, and almost totally recyclable. With the aid of TRIS, a cleaner separation Process is proposed in the present study for recovery of 1-propanol and 2-propanol from their aqueous solutions based on buffer-swing distillation.
Yanbo Wang - One of the best experts on this subject based on the ideXlab platform.
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Impacts of government subsidies and environmental regulations on Green Process innovation: A nonlinear approach
Technology in Society, 2020Co-Authors: Jingjing Liu, Min Zhao, Yanbo WangAbstract:Abstract With China's tremendous economic development following its reform and opening-up, the problem of environmental deterioration has become increasingly serious. To achieve a win-win situation between economic growth and environmental protection, enterprises are being encouraged to carry out Green technology innovation, but due to the risks and uncertainties inherent in it, the government is providing research and development (R&D) subsidies while at the same time implementing environmental regulations. As the Organisation for Economic Cooperation and Development (OECD) [5] divides Green technology innovation into Green product innovation and Green Process innovation, this study focuses on the latter in order to better study its relationship with environmental regulations and government subsidies. We select panel data of 30 provinces and cities in China from 2009 to 2017 (excluding Tibet, Hong Kong, Macao, and Taiwan, because of a lack of data) and use the system GMM and threshold-effect model for empirical analysis. The results show that environmental regulations have a U-shape non-linear effect on Green Process innovation, while government subsidies have a positive role in promoting Green Process innovation, or the so-called leverage effect. Based on government subsidies, the impact of environmental regulations on Green Process innovation has a threshold effect, and therefore regulations and subsidies should be increased. In addition, the level of economic development has a U-shape effect of inhibition and then promotion on Green Process innovation. Overall, the China government should continue to develop its economy, but must not neglect the impact of environmental regulations on technological innovation at the expense of environmental damage.
Zhang Zhengshi - One of the best experts on this subject based on the ideXlab platform.
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Green Process to prepare water-insoluble silk scaffolds with silk I structure
International journal of biological macromolecules, 2018Co-Authors: Zhang Zhengshi, Ding Zhaozhao, Huang Ji-wei, Qin Jianzhong, Shen Yixin, Zhang Feng, Zuo BaoqiAbstract:Abstract Silk porous scaffolds have shown promising applications in tissue regenerations as cellular scaffolds to incorporate cells in vitro and in vivo , and facilitate cell proliferation and production of extracellular matrix. It remains strong needs to optimize the microstructures and performances of silk scaffolds for better biocompatibility. Here, a Green Process was developed to form water-insoluble scaffolds. Repeated freezing-dissolving procedures and silk nanofibers were introduced to tune the performances of the scaffolds, resulting in amorphous conformations and nanofibrous structures. Controllable degradation and mechanical properties as well as improved cell compatibility were then achieved for these scaffolds, suggesting their promising future in tissue regenerations. Our present results confirmed the possibility of actively designing silk scaffolds with preferable properties used in various tissue regenerations.
