10 research outputs found
Formation of casting solutions of membranes.
<p>Formation of casting solutions of membranes.</p
Ultrastructure of HepG2 and HK-2 cells cultured for 144 h on F127 membrane.
<p>nuclear (N), mitochondria (M), lipid droplet (L), glycogen particle (Gly), bile duct (BD), microvillus (Mic).</p
Liver-specific functions of rat hepatocytes and HepG2 cultured on various membranes.
<p>Urea production (A), albumin secretion (B), cytochrome P450 (CYP) 1A2 activity (C), and CYP 3A activity (D) are presented as means ± SD of three measurements. # and * represent significant differences (p<0.05) compared to the respective control on well bottom surfaces (WBS).</p
RT-PCR analysis for cell expression of genes coding for integrin β1 (<i>ITGB1</i>) and E-cadherin (<i>CDH1</i>) on various membranes and well bottom surfaces (WBS).
<p><i>GAPDH</i> was used as housekeeping gene, and its expression served as control.</p
Morphology of HK-2, MDCK, and HepG2 cell lines and rat hepatocytes cultured for 144 h on various membranes.
<p>Cell images were detected by scanning electron microscope. Scale bar represents 50 µm.</p
Renal tubular-cell specific functions of HK-2 and MDCK renal tubular cells cultured on various membranes.
<p>γ-glutamyltransferase activity (A), alkaline phosphatase activity (B), and Mrp2 activity (C) are presented as means ± SD of three measurements. # and * represent significant differences (p<0.05) compared to the respective control on well bottom surfaces (WBS).</p
Cell proliferation on various membranes.
<p>Well bottom surfaces (WBS) were used as controls.</p
Cell attachment 4 h after seeding.
<p>A: in 10% FBS medium; B: in protein-free medium. Well bottom surfaces (WBS) were used as controls.</p
Heat-Treated Polyacrylonitrile (PAN) Hollow Fiber Structured Packings in Isopropanol (IPA)/Water Distillation with Improved Thermal and Chemical Stability
In this study, polyacrylonitrile
(PAN) hollow fiber membrane (HFM)
was heat-treated by muffle furnace to strengthen the thermal and chemical
stability. Membrane morphology with different materials was characterized
by scanning electron microscopy (SEM). It has shown that both porosity
and pore size decreased with increasing heat treatment time (<i>t</i> = 0.5, 6, 12 h) and temperature (<i>T</i> =
200, 250, 300, and 350 °C). FTIR was used to explore the change
of chemical bonds and found that dehydrogenation, cyclization, and
cross-linking reactions occurred in thermal treatment. Compared with
original PAN membrane, the hydrophobicity of heat-treated membranes
was obviously improved. The heat-treated membrane PAN-250-6 (PAN–temperature–duration)
was selected and immersed in various boiling solvents for 24 h to
test material stability. PAN-250-6 membrane presented excellent thermal
and chemical stability especially in strong solvent, <i>N</i>,<i>N</i>-dimethylacetamide (166.1 °C), whereas original
PAN membrane was dissolved completely. For comparison, PAN and PAN-250-6
HFMs were further chosen for packing modules, which were used for
the distillation of isopropanol–water solution. During 10 days
of operation, module PAN-250-6 showed high separation efficiency with
comparatively low height of mass transfer unit (HTU) and larger overall
mass transfer coefficients in the ranges of 0.1–0.18 m and
2.5–3.2 cm/s respectively. By analyzing the impact of wetting
condition on mass transfer, it was found that membrane resistance
should be sensitive and attributed more to the change of the overall
resistance. The membrane with better hydrophobicity after heat treatment
was more conducive to distillation with HFMs. With superior thermal
and chemical stability in distillation, this kind of heat-treated
hollow fiber structured packing will be promising in future distillation
applictions
Amphiphilic Interlayer Regulated Interfacial Polymerization for Constructing Polyamide Nanofiltration Membranes with High Perm-Selectivity of Mono-/Divalent Salts
High-quality thin-film composite
(TFC) membranes with high selectivity
and permeability have great significance owing to their practical
applications, specifically for the accurate differentiation of monovalent
and divalent ions. However, the trade-off effect between selectivity
and permeability is still a big challenge due to the difficult structure
adjustment of the selective layer. Herein, polydopamine (PDA) functionalized
with a hydrophobic long alkane chain was first explored as a functional
amphiphilic interlayer to synthesize high-quality TFC membranes via
a confined interfacial polymerization (IP) reaction. The amphiphilic
interlayer not only restricted the formation of the polyamide (PA)
matrix in the pores of the substrate but also accelerated spatially
more homogeneous polymerization and formed a PA active layer with
a more uniform pore size distribution. The method may provide an effective
principle for the construction of versatile polyamide-based membranes
with high perm-selectivity on various supports. The NaCl/Na2SO4 separation factor of the D-8/PA membrane reached as
high as 204.07, while the flux increased up to 25.71 L m–2 h–1 bar–1. This progress provides
a more feasible way for the construction of high-quality TFC membranes
with a devisable and creative amphiphilic interlayer for industrial
application