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The punching severe deformation is a recently developed surface treatment that forms alloying by inducing a greater compressive equivalent stress field. Despite its proven utility, there has been little attention devoted to the accurate modeling of this process. In this work, a 3D-DEFORM finite element analysis was used to model the equivalent stress distribution induced by the punching process on a low-carbon steel surface. A majority of the controlling parameters of the process were taken into account. The effect of punching number, punching tip size, punching velocity and punching pressure on the equivalent stress distribution was evaluated. The results show that an equivalent stress distribution much higher than the conventional surface severe deformation can be obtained by optimizing the punching severe deformation process. The reported simulation results can successfully predict the punching severe deformation used to create an alloying layer on the surface of low-carbon steel. [ABSTRACT FROM AUTHOR]

Abstract: This study systematically investigates the organic fouling behavior of a superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membrane functionalized via post-fabrication tethering of surface-tailored silica nanoparticles to poly(methacrylic acid)-grafted PVDF membrane surface. Sodium alginate (SA), Suwannee River natural organic matter (SRNOM), and bovine serum albumin (BSA) were used as model organic foulants to investigate the antifouling behavior of the superhydrophilic membrane with combined-fouling (mixture of foulants) and individual-fouling (single foulant) tests. A membrane bioreactor (MBR) plant supernatant was also used to verify the organic antifouling property of the superhydrophilic membrane under realistic conditions. Foulant size distributions and foulant–membrane interfacial forces were measured to interpret the observed membrane fouling behavior. Molecular weight cutoff measurements confirmed that membrane functionalization did not adversely affect the intrinsic membrane selectivity. Both filtration tests with the synthetic foulant-mixture solution (containing SA, SRNOM, and BSA) and MBR plant supernatant demonstrated the reliability and durability of the antifouling property of the superhydrophilic membrane. The conspicuous reduction in foulant–membrane interfacial forces for the functionalized membrane further verified the antifouling properties of the superhydrophilic membrane, suggesting great potential for applications in wastewater treatment. [Copyright &y& Elsevier]

Abstract: Starting from the oxindole 2a identified through a high-throughput screening campaign, a series of NaV1.7 blockers were developed. Following the elimination of undesirable structural features, preliminary optimization of the oxindole C-3 and N-1 substituents afforded the simplified analogue 9b, which demonstrated a 10-fold increase in target potency versus the original HTS hit. A scaffold rigidification strategy then led to the discovery of XEN907, a novel spirooxindole NaV1.7 blocker. This lead compound, which in turn showed a further 10-fold increase in potency, represents a promising structure for further optimization efforts. [Copyright &y& Elsevier]

A thermal lens insensitive regenerative amplifier (RA) with a dual Yb:CaYAlO 4 (Yb:CYA) crystal configuration for extending gain spectra is demonstrated for the first time, to the best of our knowledge. By orthogonalizing the orientation of two a-cut Yb:CYA crystals in one RA, the Q switched spectrum with a full width at half maximum of 15.4 nm is generated, which is 1.5 and 1.6 times of the Q switched spectral bandwidth with π- and σ-polarization, respectively. With chirped pulses injection, this RA can deliver laser pulses with an average power exceeding 10 W at the repetition rate of 20-800 kHz and pulse energy of 1.5 mJ at 1 kHz. This is the highest average power from the Yb:CYA RA to the best of our knowledge. Finally, compressed pulses of 163 fs with 92% overall efficiency are realized. Thanks to the heat insensitive cavity design and excellent thermodynamic properties of the Yb:CYA crystal, the output laser beam is close to the diffraction limit with an M 2 value of 1.07 × 1.07.

The hydrophobicity of ultrafiltration membranes is the main cause of membrane fouling and reduced permeability, so it is necessary to improve the hydrophilicity and anti-fouling performance of ultrafiltration membrane materials. MoS 2 nanoparticles that were modified with polydopamine (PDA) and polyethyleneimine (PEI), named MoS 2 -PDA-PEI, were added to fabricate a polyethersulfone ultrafiltration membrane (PES/MoS 2 -PDA-PEI) for the first time. The effects of modified MoS 2 nanoparticles on membrane performance were clarified. The results indicated that the permeability, rejection, and anti-fouling capability of the hybrid PES/MoS 2 -PDA-PEI membrane have been improved compared with the pristine PES membrane. When the content of MoS 2 -PDA-PEI nanoparticles in the membrane is 0.5%, the pure water flux of the hybrid membrane reaches 364.03 L m -2 h -1 , and the rejection rate of bovine serum albumin (BSA) and humic acid (HA) is 96.5% and 93.2% respectively. The flux recovery rate of HA reached 97.06%. As expected, the addition of MoS 2 -PDA-PEI nanoparticles promotes the formation of the porous structure and improves the hydrophilicity of the membrane, thereby improving its antifouling performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: The predicted amino acid sequence of locus plu4437-plu4436 in the genome of Photorhabdus luminescens TT01 (referred to as pirA2B2) has a consistency of 50% and 45% with locus plu4093-plu4092 (referred to as pirA1B1) , respectively. PirA1B1 has been confirmed with oral insecticidal activity against Plutella xylostella and mosquito. The purpose of the present study was to examine whether pirA2B2 possesses insecticidal activity., Methods: pirA2, pirB2 and pirA2B2 genes were PCR amplified and cloned. The recombinant expression vector pQE-pirA2, pQE-pirB2 and pQE-pirA2B2 were constructed and transferred into E. coli M15, individually. The soluble PirA2, PirB2 and PirA2B2 proteins were detected from the supernatant of the recombinant M15 induced with IPTG by both SDS-PAGE and Western-blot. The proteins expressed in the three recombinant E. coli M15 strains were purified by affinity chromatography combined with desalination technology and then quantified individually. The heamocoal and oral insecticidal activities of the expressed proteins were analyzed against the larvae of Galleria mellonella and Spodoptera litura., Results: The results show: 1. PirA2B2 had heamocoal insecticidal activity against the fifth instar larvae of both G. mellonella and S. litura, with an LD50 of 4.0 and 2.8 microg/larvae, respectively, 2. neither PirA2 nor PirB2 alone had heamocoal insecticidal activity against the insects tested, while the mixture of PirA2 and PirB2 reconstituted full activity, and 3. PirA2B2 showed no oral insecticidal activity to the first instar larvae of either G. mellonella or S. litura., Conclusion: pirA2B2 in the genome of P. luminescens TT01 is a binary insecticidal toxin gene., Significance: The successful expression and purifcation of PirA2B2 laid a foundation for further study on the function, insecticidal mechanism and expression regulation of the binary toxins.