Design of PDMS/PAN composite membranes with ultra-interfacial stability via layer integration.

The interfacial interaction between the selective layer and porous substrate directly determines the separation performance and service lifetime of functional composite membranes. Till now, almost all reported polymeric selective layers are physically in contact with the substrate, which is unsatisfactory for long-term operation. Herein, we introduced a functional composite membrane with ultra-interfacial stability via layer integration between the polydimethylsiloxane selective layer and polyacrylonitrile substrate, where a facile light-triggered copolymerization achieved their covalent bonding. The critical load for the failure of the selective layer is 45.73 mN when testing the interfacial adhesion, i.e., 5.8 times higher than that before modification and significantly higher than previous reports. It also achieves superior pervaporation performance with a separation factor of 9.54 and membrane flux of 1245.6 g m-2 h-1 feeding a 1000 ppm phenol/water solution at 60 °C that is significantly higher than the same type of polymeric ones. Not limited to pervaporation, such a strategy sheds light on the design of highly stable composite membranes with different purposes, while the facile photo-trigged technique shows enormous scalability.

Photo-Modulated Ionic Polymer as an Adaptable Electron Transport Material for Optically Switchable Pixel-Free Displays.

In addition to electrically driven organic light-emitting diode (OLED) displays that rely on complicated and costly circuits for switching individual pixel illumination, developing a facile approach that structures pixel-free light-emitting displays with exceptional precision and spatial resolution via external photo-modulation holds significant importance for advancing consumer electronics. Here, optically switchable organic light-emitting pixel-free displays (OSPFDs) are presented and fabricated by judiciously combining an adaptive photosensitive ionic polymer as electron transport materials (ETM) with external photo-modulation as the switching mode while ensuring superior illumination performance and seamless imaging capability. By irradiating the solution-processed OSPFDs with light at specific wavelengths, efficient and reversible tuning of both electron transport and electroluminescence is achieved simultaneously. This remarkable control is achieved by altering the energetic matching within OSPFDs, which also exhibits a high level of universality and adjustable flexibility in the three primary color-based light-emitting displays. Moreover, the ease of creating and erasing desired pixel-free emitting patterns through a non-invasive photopatterning process within a single OSPFD is demonstrated, thereby rendering this approach promising for commercial displaying devices and highly precise pixelated illuminants.

Self-wrinkling coating for impact resistance and mechanical enhancement.

Protective materials are essential for personal, electronic, and military defenses owing to their efficient impact-resistant and energy-absorbing properties. Inspired by the bottom-up fabrication process and energy dissipation mechanism of natural organisms with hierarchical structures, we demonstrated a self-wrinkled photo-curing coating as a new protective material for enhancing the anti-impact property of the substrates. Owing to the self-assembly of polydimethylsiloxane (PDMS) containing polymeric photoinitiator on the surface, the liquid coating formulation was photo-cured by one-step UV irradiation with simultaneous generation of self-wrinkled surface morphology and a gradient cross-linked architecture. The maximum impact resistance height (hmax) of the glass substrate coated with plain coating increased from 120 to 180 cm when coated with wrinkled gradient coating. Furthermore, the Young's modulus, fracture stress, and toughness of the wrinkled gradient coating film improved from 39.6 MPa, 2.4 MPa, and 74.1 MJ/cm3 to 235.0 MPa (∼5× increase), 18.5 MPa (∼6.6× increase), and 845.0 MJ/cm3 (∼10.8× increase) compared to the pure coating film as reference. The theoretical simulation and experimental results proved that the surface self-wrinkled morphology and intrinsic hierarchical architecture contribute to the energy dissipation and impact resistance of the cured coating. The photo-curing process, a bottom-up strategy, is conducted in a non-contact mode compared with nano-printing and lithography, enabling bulk materials to be engineered.

Catalytic hairpin assembly assisted target-dependent DNAzyme nanosystem coupled with AgPt@Thi for the detection of lead ion.

An ultrasensitive electrochemical biosensor for detection of lead ions (Pb2+) is proposed based on catalytic hairpin assembly and target-induced DNAzyme signal amplification strategy. Polyethyleneimine-reduced graphene oxide (PEI-rGO) combined with gold@silver nanosheets (Au@Ag NSs) are used as electrode substrate modification materials, which not only increase the specific surface area but also exhibit stronger conductivity than pure PEI-rGO or Au@Ag NSs. Hairpin chain 1 (HP1) is immobilized on the surface of modified electrode by Au-S. Then trigger (Tr) DNA can induce the opening of the HP1 hairpin, thus exposing the binding sequence to hybridize with Hairpin chain 2 (HP2) and catalyzing the opening and binding of the hairpin HP2. The process is cyclic and will produce abundant HP1-HP2 duplex strands. When Pb2+ is present, it can catalyze DNAzyme (Pb2+-HP2) to specifically cut the substrate chain HP1, and only a partial sequence of HP1 remains on the surface of the electrode. Finally, the signal probe (AgPt@Thi-CP) can be hybridized with the part of the HP1 sequence after being cut to generate a significant electrical signal. Under optimal conditions, the Pb2+ concentration measured by prepared electrochemical biosensor has a good linear relationship in the range of 0.05 pM-5 nM, and the detection limit is 0.028 pM. This method can be used for the trace detection of Pb2+ in tap water samples, and it also provides a platform for the detection of other targets.

[Manipulative reduction for lumbar intervertebral disc herniation: a controlled clinical trial].

OBJECTIVE: To investigate the effects of manipulative reduction on pain and clinical curative effect in patients with lumbar intervertebral disc herniation. METHODS: Eleven thousands one hundred and twenty-eight patients with lumbar intervertebral disc herniation from our hospital were enrolled from November 1986 to June 2007. They were randomly divided into control group and treatment group. Patients of the control group received lumbar traction and various physiotherapies. Patients of the treatment group received manipulative reduction, besides the treatment in the control group. The treatment was performed once a day,ten times as a course. Curative effects were assessed three courses later. Pain was evaluated by visual analogue scale before and after the treatment. RESULTS: No significant difference in the score of visual analogue scale was found before the treatment in the two groups (P > 0.05). As compared with the score before treatment,it was decreased by 4.73 points after treatment in the control group, and decreased by 6.37 points in the treatment group. The decrease was more significant in the treatment group than the control group (P < 0.01). The healing rate was 47.28% and total effective rate was 96.37% in the control group; The healing rate was 73.44% and total effective rate was 98.61% in the treatment group (P < 0.01). CONCLUSION: Manipulative reduction for lumbar intervertebral disc herniation can remarkably relieve lumbar pain and improve clinical curative effect.