Polypropylene Blends with Durable Hydrophobicity and Enhanced Mechanical Properties Based on POSS and Alkane Modified Polypentafluorophenyl Methacrylate.

Durable functionalization on polypropylene (PP) surfaces is always a key problem to besolved. Coatings with low surface energy peel off easily especially under extreme conditions, owing to their weak adhesion. In this paper, side groups of both polyhedral oligomeric silsesquioxane (POSS) and alkane are grafted to polypentafluorophenyl methacrylate (PFP), and then PP blends with these side-group modified PFP are obtained through a melt-blending process. It is found that POSS can result in surface segregation and provide hydrophobicity in blends. Microfibers are formed because of the orientation effect during the tensile testing, which furtherly promotes mechanical strength. Significantly, alkaneside-groups can be entangled with PP segments, which brings about cross linking. Therefore, with crosslinking and synchronous orientation of POSS, the elongation at the break of blends is greatly increased up to 974%. The final blend demonstrates quite durable hydrophobicity under many extreme conditions, such as repeated tape peeling, ultrasonic washing, strong friction, and soaking in strong acid (pH = 1), strong alkali (pH = 14) and alcohol. The heat and UV resistance of the blend are also obviously improved. This study will develop anovel and facile strategy to endow PP with durable hydrophobicity as well as greatly enhanced mechanical properties.

Ion adsorption-enrichment effect and its driving mechanism for nano-dots lithography with SPM probe on water-soluble crystal surfaces.

HYPOTHESIS: Water-soluble KDP (KH2PO4) crystals possess excellent optical properties and are employed as frequency converters in clean fusion energy. To improve their performances, there is an immediate necessity to lithograph surface nano-patterns on them. Although the Scanning Probe Microscope (SPM) provides a promising way to achieve this purpose through the water menisci, the driving mechanisms of the lithographic behaviors have not yet been revealed. SIMULATIONS AND EXPERIMENTS: Multi-scale investigations are constructed to explore the underlying driving mechanisms. The SPM probe-induced ion diffusion-transport behaviors are investigated by molecular dynamics. The ion adsorption-enrichment mechanisms are revealed by 18 adsorption models via the ab initio. The SPM probe-induced self-assembly experiments are performed to prove the local heavy concentration. A comprehensive model is developed to describe the lithography mechanisms of the probe-induced self-assembly nano-dots on water-soluble substrates. FINDINGS: It is interestingly found that the KDP growth units (H2PO4-) exhibit obvious adsorption-enrichment effect at 3.16 Å from the probe surface, causing local heavy concentration. The H2PO4- would spontaneously adsorb onto the probe surface, which is dominated by the Si-O bonding reactions. The nano-dots with the height of 27 âˆ¼ 48 nm and diameter of 2.0 âˆ¼ 2.7 µm are lithographed on the KDP substrate. The proposed model further confirms that the lithography processes are driven by the solution supersaturation, solute diffusion, and surface free energy.

Experimental study on reservoir particle migration induced by the injection-production process of underground gas storage.

Multi cycle injection and production of underground gas storage (UGS) promote continuous changes in reservoir characteristics, to clarify the impact of different injection and production characteristics on the reservoir, taking carbonate rock fracture-pore type gas storage reservoirs as the research object, established a set of experimental methods based on production characteristics, quantitative analysis of reservoir damage caused by particle migration caused by increasing, decreasing, fluctuating, and reverse changes in production pressure difference. And the following research results are obtained. First, established experimental methods based on production characteristics, the production method includes increasing, decreasing, fluctuating, and reverse changes, realized experimental evaluation of simulating actual production full features. Second, there is a critical pressure difference in the migration of reservoir particles, the fluctuation of production pressure difference induce further migration of particles, resulting in natural unblocking or new blockage. Third, the change in the direction of production pressure difference can cause large particle sizes break into small particle sizes and migrate out of the pore throat, thus the permeability of the reservoir can be improved to a certain extent. It is concluded that controlling a certain production pressure difference during the injection and production process of UGS, not only meets production needs, but also alleviate the damage of injection production to reservoir permeability to a certain extent.

Genome-wide identification and expression analysis of the CONSTANS-like family in potato (Solanum tuberosum L.).

The CONSTANS-like (COL) gene plays important roles in plant growth, development, and abiotic stress. A total of 15 COL genes are unevenly distributed on eight chromosomes in the potato genome. The amino acid length of the family members was 347-453 aa, the molecular weight was 38.65-49.92 kD, and the isoelectric point was 5.13-6.09. The StCOL family can be divided into three subfamilies by evolutionary tree analysis, with conserved motifs and similar gene structure positions in each subfamily. The analysis of promoter cis-acting elements showed 17 cis-acting elements related to plant hormones, stress, and light response. Collinearity analysis of COL genes of tomato, potato, and Arabidopsis showed that 13 StCOL genes in the different species may have a common ancestor. A total of 10 conserved motifs and six kinds of post-translational modifications in the 15 StCOL proteins were identified. The 15 StCOL genes exhibit a genomic structure consisting of exons and introns, typically ranging from two to four in number. The results showed that 10 genes displayed significant expression across all potato tissues, while the remaining five genes were down-expressed in potato transcriptome data. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis exhibited differential expression of 8 StCOL genes in the potato leaves and tubers at different growth stages, as well as 7 StCOL genes under 2°C treatment conditions. These results suggested that the StCOL gene family may play an important role in regulating potato tuberization and responding to cold stress.

Multiple free-radical-trapping and hydrogen-bonding-enhanced polyurethane foams with long-lasting flame retardancy, aging resistance, and toughness.

Flexible polyurethane foam (FPUF) is a ubiquitous material utilized in furniture cushions, mattresses, and various technical applications. Despite the widespread use, FPUF faces challenges in maintaining long-lasting flame retardancy and aging resistance, particularly in harsh environments, while retaining mechanical robustness. Here, we present a novel approach to address these issues by enhancing FPUF through multiple free-radical-trapping and hydrogen-bonding mechanisms. A hindered amine phosphorus-containing polyol (DTAP) was designed and chemically introduced into FPUF. The distinctive synergy between hindered amine and phosphorus-containing structures enables the formation of multiple hydrogen bonds with urethane, while also effectively capturing free radicals across a broad temperature spectrum. As a result, incorporating only 5.1 wt% of DTAP led to the material successfully passing vertical burning tests and witnessing notable enhancements in tensile strength, elongation at break, and tear strength. Even after enduring accelerated thermal aging for 168 hours, the foam maintained exceptional flame retardancy and mechanical properties. This study offers novel insights into material enhancement, simultaneously achieving outstanding long-lasting flame retardancy, toughness, and anti-aging performance.

Mechanism of Interconnected Pore Formation in High Internal Phase Emulsion-Templated Polymer.

High internal phase emulsion-templated polymer, named polyHIPE, has received widespread attention due to its great potential applications in many fields, such as separation, adsorption, heterogeneous catalysis, and sound absorption. The broad applicability is largely dependent on its adjustable opening structure. However, the question of why polyHIPE has an interconnected pore network structure is still to be discussed. Herein, different types (w/o, o/w, and o/o) of HIPEs are prepared and subsequently detected with laser scanning confocal microscopy (LSCM), and the polyHIPEs obtained by curing the HIPEs are characterized by SEM. The observations suggest that the interconnected pore formation is primarily due to the presence of the surfactant-rich phase in the film between the neighboring droplets in HIPE. The interconnected pores are generated by removal of the surfactant-rich domains in the postcuring procedure, and their sizes would be enlarged if the solubility of the surfactant in the continuous phase decreases in the curing stage.

Organic solvents-free and ambient-pressure drying melamine formaldehyde resin aerogels with homogeneous structures, outstanding mechanical strength and flame retardancy.

Atmospheric drying method for fabricating aerogels is considered the most promising way for casting aerogels on a large scale. However, the organic solvent exchange, remaining environmental pollution risk, is a crucial step in mitigating the impact of surface tension during the atmospheric drying process, especially for wet gel formed through the alkoxy-derived sol-gel process, such as melamine-formaldehyde resin (MF) aerogel. Herein, a tough polymer-assisted in situ polymerization was proposed to fabricate MF resin aerogel with a combination of mechanical toughness and strength, enabling it to withstand the capillary force during water evaporation. The monolithic MF resin aerogel through the sol-gel method can be directly prepared without additional network strengthening or organic solvent exchange. The resulting MF resin aerogel exhibits a homogeneous as well as hierarchical structure with macropores and mesopores (~6 µm and ~5 nm), high compressive modulus of 31.8 MPa, self-extinguishing property, and high-temperature thermal insulation with 97 % heat decrease for butane flame combustion. This work presents a straightforward and environmentally friendly method for fabricating MF resin aerogels with nanostructures and excellent performance in open conditions, exhibiting various applications.

PPARα phosphorylation regulates colorectal tumor immune escape.

A high level of PD-L1 in cancer cells promotes tumor immune escape and inhibits tumor immunotherapy. Although PD-L1 gene expression is upregulated by multiple pathways, its gene transcriptional repression is still unclear. Here we found that loss of PPARα, one of the peroxisome-proliferator-activated receptors (PPARs) family members, promoted colorectal tumor immune escape. Mechanistically, PPARα directly bound to the PD-L1 promoter resulting in its gene transcriptional repression, which in turn increased T cell activity, and PPARα agonist enhanced this event. However, ERK induced PPARα-S12 phosphorylation leading to blockade of PPARα-mediated PD-L1 transcriptional repression, and the combination of ERK inhibitor with PPARα agonist significantly inhibited tumor immune escape. These findings suggest that the ERK-PPARα pathway inhibited PD-L1 gene transcriptional repression and promoted colorectal tumor immune escape.

Self-evolutionary recycling of flame-retardant polyurethane foam enabled by controllable catalytic cleavage.

Polyurethane (PU) foams, pivotal in modern life, face challenges suh as fire hazards and environmental waste burdens. The current reliance of PU on potentially ecotoxic halogen-/phosphorus-based flame retardants impedes large-scale material recycling. Here, our demonstrated controllable catalytic cracking strategy, using cesium salts, enables self-evolving recycling of flame-retardant PU. The incorporation of cesium citrates facilitates efficient urethane bond cleavage at low temperatures (160 °C), promoting effective recycling, while encouraging pyrolytic rearrangement of isocyanates into char at high temperatures (300 °C) for enhanced PU fire safety. Even in the absence of halogen/phosphorus components, this foam exhibits a substantial increase in ignition time (+258.8%) and a significant reduction in total smoke release (-79%). This flame-retardant foam can be easily recycled into high-quality polyol under mild conditions, 60 °C lower than that for the pure foam. Notably, the trace amounts of cesium gathered in recycled polyols stimulate the regenerated PU to undergo self-evolution, improving both flame-retardancy and mechanical properties. Our controllable catalytic cracking strategy paves the way for the self-evolutionary recycling of high-performance firefighting materials.

Solvent-modulated luminescence of carbon dots for ion sensing and fingerprint detection.

Since carbon dots (CDs) with good water solubility are preferred by researchers and biological applications, a hydrothermal method was used to synthesize green fluorescent CDs with an excitation-independent peak at 526 nm using deionized water as the solvent and neutral red as the carbon source. To achieve spectral modulation, the pH of the solvent was adjusted with KOH to obtain orange CDs (O-CDs) in an alkaline environment, with the emission peak red-shifted to 630 nm. The water-soluble CDs were prepared for multidimension sensing as Fe3+ sensing (on/off). Carbon dots dispersed into a silica gel matrix can be used for fingerprint detection of various materials.

Piezoresistive Porous Composites with Triply Periodic Minimal Surface Structures Prepared by Self-Resistance Electric Heating and 3D Printing.

Three-dimensional flexible piezoresistive porous sensors are of interest in health diagnosis and wearable devices. In this study, conductive porous sensors with complex triply periodic minimal surface (TPMS) structures were fabricated using the 3D printed sacrificial mold and enhancement of MWCNTs. A new curing routine by the self-resistance electric heating was implemented. The porous sensors were designed with different pore sizes and unit cell types of the TPMS (Diamond (D), Gyroid (G), and I-WP (I)). The impact of pore characteristics and the hybrid fabrication technique on the compressive properties and piezoresistive response of the developed porous sensors was studied. The results indicate that the porous sensors cured by the self-resistance electric heating could render a uniform temperature distribution in the composites and reduce the voids in the walls, exhibiting a higher elastic modulus and a better piezoresistive response. Among these specimens, the specimen with the D-based structure cured by self-resistance electric heating showed the highest responsive strain (61%), with a corresponding resistance response value of 0.97, which increased by 10.26% compared to the specimen heated by the external heat sources. This study provides a new perspective on design and fabrication of porous materials with piezoresistive functionalities, particularly in the realm of flexible and portable piezoresistive sensors.

GSK0660 enhances antitumor immunotherapy by reducing PD-L1 expression.

Blockade of PD-1/PD-L1 immune checkpoint is wildly used for multiple types of cancer treatment, while the low response rate for patients is still completely unknown. As nuclear hormone receptor, PPARδ (peroxisome-proliferator-activated receptor) regulates cell proliferation, inflammation, and tumor progression, while the effect of PPARδ on tumor immune escape is still unclear. Here we found that PPARδ antagonist GSK0660 significantly reduced colon cancer cell PD-L1 protein and gene expression. Luciferase analysis showed that GSK0660 decreased PD-L1 gene transcription activity. Moreover, reduced PD-L1 expression in colon cancer cells led to increased T cell activity. Further analysis showed that GSK0660 decreased PD-L1 expression in a PPARδ dependent manner. Implanted tumor model analysis showed that GSK0660 inhibited tumor immune escape and the combined PD-1 antibody with GSK0660 effectively enhanced colorectal cancer immunotherapy. These findings suggest that GSK0660 treatment could be an effective strategy for cancer immunotherapy.

Rigid CuInS2/ZnS Core/Shell Quantum Dots for High Performance Infrared Light-Emitting Diodes.

CuInS2 (CIS) quantum dots (QDs) represent an important class of colloidal materials with broad application potential, owing to their low toxicity and unique optical properties. Although coating with a ZnS shell has been identified as a crucial method to enhance optical performance, the occurrence of cation exchange has historically resulted in the unintended formation of Cu-In-Zn-S alloyed QDs, causing detrimental blueshifts in both absorption and photoluminescence (PL) spectral profiles. In this study, we present a facile one-pot synthetic strategy aimed at impeding the cation exchange process and promoting ZnS shell growth on CIS core QDs. The suppression of both electron-phonon interaction and Auger recombination by the rigid ZnS shell results in CIS/ZnS core/shell QDs that exhibit a wide near-infrared (NIR) emission coverage and a remarkable PL quantum yield of 92.1%. This effect boosts the fabrication of high-performance, QD-based NIR light-emitting diodes with the best stability of such materials so far.

Dual function of activated PPARγ by ligands on tumor growth and immunotherapy.

As one of the peroxisome-proliferator-activated receptors (PPARs) members, PPARγ is a ligand binding and activated nuclear hormone receptor, which is an important regulator in metabolism, proliferation, tumor progression, and immune response. Increased evidence suggests that activation of PPARγ in response to ligands inhibits multiple types of cancer proliferation, metastasis, and tumor growth and induces cell apoptosis including breast cancer, colon cancer, lung cancer, and bladder cancer. Conversely, some reports suggest that activation of PPARγ is associated with tumor growth. In addition to regulating tumor progression, PPARγ could promote or inhibit tumor immunotherapy by affecting macrophage differentiation or T cell activity. These controversial findings may be derived from cancer cell types, conditions, and ligands, since some ligands are independent of PPARγ activity. Therefore, this review discussed the dual role of PPARγ on tumor progression and immunotherapy.

Catalytic polymer self-cleavage for CO2 generation before combustion empowers materials with fire safety.

Polymeric materials, rich in carbon, hydrogen, and oxygen elements, present substantial fire hazards to both human life and property due to their intrinsic flammability. Overcoming this challenge in the absence of any flame-retardant elements is a daunting task. Herein, we introduce an innovative strategy employing catalytic polymer auto-pyrolysis before combustion to proactively release CO2, akin to possessing responsive CO2 fire extinguishing mechanisms. We demonstrate that potassium salts with strong nucleophilicity (such as potassium formate/malate) can transform conventional polyurethane foam into materials with fire safety through rearrangement. This transformation results in the rapid generation of a substantial volume of CO2, occurring before the onset of intense decomposition, effectively extinguishing fires. The inclusion of just 1.05 wt% potassium formate can significantly raise the limiting oxygen index of polyurethane foam to 26.5%, increase the time to ignition by 927%, and tremendously reduce smoke toxicity by 95%. The successful application of various potassium salts, combined with a comprehensive examination of the underlying mechanisms, underscores the viability of this strategy. This pioneering catalytic approach paves the way for the efficient and eco-friendly development of polymeric materials with fire safety.

Aminopoly(carboxylic acid)-Functionalized PolyHIPE Beads toward Eliminating Trace Heavy Metal Ions from Water.

Many advanced materials are designed for the removal of heavy metal ions from water. However, materials for eliminating trace heavy metal ions from wastewater to meet drinking water standards remain a major challenge. Herein, epoxy group-functionalized open-cellular beads are synthesized by UV polymerization of a water-in-oil-in-water system. The epoxy groups are further transformed into diethylenetriaminepentaacetic acid (DTPA) with hexamethylene diamine as a bridging agent. The resulting material (DTPA@polyHIPE beads) can eliminate trace Cu(II), Cr(III), Pb(II), Fe(III), or Cd(II) from water. When 0.15 g of DTPA@polyHIPE beads are used to adsorb metal ions of 20 mg in 100 mL of water, the residue concentrations of Cu(II), Cr(III), Pb(II), Fe(III), and Cd(II) are reduced to 0.08, 0.06, 0.02, 0.09, and 0.07 mg/L, respectively. The adsorption efficiencies of the beads for these ions are all higher than 99.55%. The adsorbent is durable and exhibits good recyclability by retaining an adsorption capacity of ≥91% after 5 cycles. The negative values of ΔG in the adsorption process indicate that the adsorption is feasible and spontaneous. The chemical adsorption follows the Freundlich adsorption model, indicating a multilayer heterogeneous adsorption. The DTPA@polyHIPE beads have a great potential application in dealing with trace heavy metal ion polluted water.

Morphology and multigene phylogeny reveal three new species of Samsoniella (Cordycipitaceae, Hypocreales) from spiders in China.

The genus Samsoniella was erected based on orange cylindrical to clavate stromata, superficial perithecia and conidiophores with Isaria-like phialides and to segregate them from the Akanthomyces group. In this study, based on morphological features and multigene (SSU, LSU, TEF, RPB1 and RPB2) phylogenetic analysis six Samsoniella species parasitizing spiders were collected in China. Three of them belong to known species S.alpina, S.erucae and S.hepiali. Three new species S.anhuiensissp. nov., S.araneasp. nov. and S.fusiformisporasp. nov. are illustrated and described. They are clearly distinct from other species in Samsoniella occurring in independent subclades. Furthermore, among the four insect-pathogenic fungi specimens collected from similar sites, three of them were identified as the new species described below. Our study significantly broadens the host range of Samsoniella from Insecta to Arachnida, marking a noteworthy expansion in understanding the ecological associations of these fungi. Additionally, the identification of both mononematous and synnematous conidiophores in our study not only expands the knowledge of Samsoniella species but also provides a basis for future research by comparing the ecological significance between these conidiophore types. In conclusion, our study enhances the understanding of Samsoniella diversity, presenting a refined phylogenetic framework and shedding light on the ecological roles of these fungi in spider parasitism.

Ultrafast Process Characterization of Laser-Induced Damage in Fused Silica Using Pump-Probe Shadow Imaging Techniques.

This study delves into the intricate dynamics of laser-induced damage in fused silica using a time-resolved pump-probe (TRPP) shadowgraph. Three typical ultra-fast processes, laser-induced plasma evolution, shockwave propagation and material fracture splashing, were quantitatively investigated. The results indicate that the diameter of plasma is proportional to the pulse laser energy and increases linearly during the pulse laser duration with an expansion rate of approximately 6 km/s. The maximum shockwave velocity on the air side is 9 km/s, occurring at the end of the pulse duration, and then rapidly decreases due to air resistance, reaching approximately 1 km/s around a 300 ns delay. After hundreds of nanoseconds, there is a distinct particle splashing phenomenon, with the splashing particle speed distribution ranging from 0.15 km/s to 2.0 km/s. The particle sizes of the splashing particles range from 4 µm to 15 µm. Additionally, the smaller the delay, the faster the speed of the splashing particles. Overall, TRPP technology provides crucial insights into the temporal evolution of laser-induced damage in fused silica, contributing to a comprehensive understanding essential for optimizing the performance and safety of laser systems.

A Review on Machining SiCp/Al Composite Materials.

SiCp/Al composite materials are widely used in various industries such as the aerospace and the electronics industries, primarily due to their excellent material properties. However, their machinability is significantly weakened due to their unique characteristics. Consequently, efficient and precise machining technology for SiCp/Al composite materials has become a crucial research area. By conducting a comprehensive analysis of the relevant research literature from both domestic and international sources, this study examines the processing mechanism, as well as the turning, milling, drilling, grinding, special machining, and hybrid machining characteristics, of SiCp/Al composite materials. Moreover, it summarizes the latest research progress in composite material processing while identifying the existing problems and shortcomings in this area. The aim of this review is to enhance the machinability of SiCp/Al composite materials and promote high-quality and efficient processing methods.

Prediction of Nanoscale Water Meniscus Shape between Deliquescent KDP Crystal Optics and AFM Probe for Water-Dissolution Repairing.

KDP (KH2PO4) crystal optics are the key elements for megajoule laser facilities. Nanoscale surface defects would cause laser-induced damage when the optics are irradiated by a high-fluence laser (over 10 J/cm2). Dip-pen nanolithography (DPN) could be used to repair the nanoscale surface defects in the KDP optics by the water meniscus. The high humidity required for high-efficiency and soft KDP surfaces penetrated by the AFM probe brings challenges for accurately predicting the water meniscus shape to evaluate the effectiveness of the DPN water-dissolution repairing. The multisolutions of the Young-Laplace and Kelvin equations also lead to the wrong water meniscus shape. A theoretical model that takes the high humidity and the penetration of the AFM probes into account is developed. The parametrization Young-Laplace equations are adopted for the zero contact angle of the water films, and the AFM probe is treated as the combination of the cone and sphere for the water meniscus whose size is larger than the AFM tip radius under high humidity. The penetration of the AFM probe is modeled by Hertz theory. Both the water films (3.3 nm thickness at 99% relative humidity) and indentations (1.46 nm depth at 300 nN contact force) are non-negligible for the nanoscale water meniscus between the KDP surface and the AFM probe. Moreover, the rough-fine two-step method is proposed to lock the correct solution of the Young-Laplace and Kelvin equations. The effectiveness of the proposed model is verified by comparison with reported ESEM images and pull-off forces. In addition, the overgrowth dots on the KDP surface are compared with the water meniscus. The linear growth of the water meniscus would cause the linear growth of the overgrowth dot, which proves the proposed model could be used to guide the DPN water-dissolution repairing for the nanoscale surface defects in the KDP optics.