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The Kuroshio intrusion into the South China Sea (SCS) in summer is weak and has rarely been reported by in situ observations. Here, we describe a new form of Kuroshio water intrusion that is strongest during the summer, the North Luzon Warm Eddy (NLWE), which is an anticyclonic eddy originating north of Luzon Island. From early July to mid-September 2018, two NLWEs moving northwestward were captured by a mooring array consisting of 27 current- and pressure-recording inverted echo sounders (CPIESs). The three-dimensional CPIES estimates reveal that the NLWEs carried large amounts of saline Kuroshio waters (S > 34.7 psu) in the subsurface, which was also evidenced by Argo float profiles. The Kuroshio intrusion was confined to waters shallower than the 14.8°C isotherm. Historical data for NLWEs suggest that they occur mostly during the summer but are absent between November and March, which is attributed to seasonal wind stress curl (WSC). However, because the seasonal signal of WSC during summer is small, intraseasonal WSC is directly responsible for the generation of NLWEs. Significance Statement This paper describes a new type of Kuroshio water intrusion into the South China Sea (SCS)—the North Luzon Warm Eddy (NLWE), which is an anticyclonic eddy generated north of Luzon Island. The eddy mostly occurs during summer when the Kuroshio intrusion is commonly considered the weakest. From observations of a large CPIES array, we provide a cradle-to-grave picture of the NLWE. NLWEs are estimated to contribute almost half of the westward Luzon Strait transport during the summer and, as such, play an important role in the seasonal stratification and circulation in the northeastern SCS.

Topographic Rossby waves (TRWs) play an important role in deep-ocean dynamics and abyssal intraseasonal variations. Observational records from 15 current- and pressure-recording inverted echo sounders (CPIESs) and two moorings deployed in the northern Manila Trench (MT), South China Sea (SCS), for over 400 days were utilized to analyze the widely existing near-21-day bottom-trapped TRWs in the trench. The TRWs were generally generated in winter and summer, dominated by perturbations in the upper ocean. Kuroshio intrusion and its related variabilities contributed to the perturbations in winter, whereas the perturbations generated north of Luzon Island dominated in summer. Eddies north of Luzon propagated northwestward in the summer of 2018; however, these eddies caused the Kuroshio meanderings in the Luzon Strait (LS) in the summer of 2019. The variations in the Kuroshio path and the Kuroshio-related eddies induced TRWs in the deep ocean in regions with steep topography. However, the spatiotemporal distributions of TRWs were complex owing to the propagation of the waves. Some cases of TRWs showed no relation to the local upper-layer perturbations but propagated from adjacent regions. Some of these TRWs were induced by perturbations in the upper ocean in adjacent regions, and propagated anticlockwise in the MT with shallow water to their right, while others may be related to the intraseasonal variations in deep-water overflow in the LS and propagated northward. This study suggests that the Kuroshio and Kuroshio-related eddies significantly contribute to the dynamic processes associated with intraseasonal variations in the deep SCS through the generation of TRWs. Significance Statement Topographic Rossby waves (TRWs) are fluctuations generated when water columns travel across sloping topography under potential vorticity conservation. Based on observations of 15 current- and pressure-recording inverted echo sounders (CPIESs) and two moorings in the northern Manila Trench (MT) in the South China Sea (SCS), TRWs with periods of approximately 21 days were observed and analyzed. This study describes the generation, propagation, and spatiotemporal distribution of TRWs west of the LS and confirms that regional Kuroshio meanderings and upper eddies play important roles in the dynamic processes associated with intraseasonal variations in the deep SCS; the study may thus contribute to knowledge on the dynamic response of the abyssal current to mesoscale perturbations in the upper ocean.

Permanent magnet linear synchronous motor (PMLSM) has a wide application prospect in transmission systems of automatic production, logistics and other fields. However, the existing PMLSM has the problems of poor flexibility and large thrust fluctuation adapted to load and stroke variation. In order to solve this problem, a dual-modular PMLSM is proposed. The motor can be flexibly configured with multiple-unit-primary (MUP) and multiple-unit-secondary (MUS), and achieve low thrust fluctuation. The matching criterion of unit-primary (UP) and secondary is established to reveal the relationship between the slot/pole combination and the winding utilization. The rules of the average thrust varying with the different UP and unit-secondary (US) lengths are illustrated. Then, the matching criterion of different UP is proposed, and the optimization method of the spacing between UP (S1) is obtained by establishing the end force model. The design standard of the optimal S1 is obtained by combining the two factors of minimum detent force and maximum thrust. The results are verified by the simulation and experiments on a 3UP-96US dual-modular PMLSM circular transmission line system and its prototype.

South China Sea (SCS) abyssal circulation largely contributes to water renewal, energy budget, and sedimentary processes in the deep ocean. The three-dimensional abyssal circulation west of the Luzon Strait (LS) in the northern SCS was investigated using an array comprising 27 current- and pressure-recording inverted echo sounders. Over 400 days of measurements from June 2018 to July 2019 showed a narrow and strong (∼70 km, ∼2.3 cm s−1 at 2500 dbar) northward current near the steep eastern boundary, while a wide and weak (∼180 km, ∼1.5 cm s−1 at 2500 dbar) southwestward current lies along the subdued western boundary. The circulation showed conspicuous cyclonic patterns with a volume transport of ∼1.21 ± 0.93 Sv (1 Sv ≡ 106 m3 s−1) and ∼1.59 ± 0.95 Sv below 2500 dbar along the eastern and western boundaries, respectively. The current near the LS was strong in late autumn and early winter but weak in late winter and spring, following the seasonal variation of LS deep-water overflow. However, the southwestward current in the interior SCS was stronger in summer and early autumn but weaker in late winter and early spring. The different seasonal patterns identified near the LS and the interior SCS are attributed to the propagation of seasonal variation. The weak current along the western boundary in August 2018 and February 2019 was dominated by LS deep-water overflow with a time lag of ∼7.5 months. Although eddies in the upper ocean may also contribute to such variation through pressure work, the effect is minor. Significance Statement Cyclonic circulation in the deep South China Sea (SCS) largely contributes to water renewal, energy budget, and sedimentary processes and influences the transport of dissolved elements, minerals, and pollutants. As an important part of the SCS throughflow, an in-depth analysis of the SCS abyssal circulation may also contribute to understanding Indonesian Throughflow and global climate change. The three-dimensional abyssal circulation west of the Luzon Strait was investigated using large-scale data from June 2018 to July 2019, which provided unprecedented coverage of abyssal circulation in the northeast SCS. The study provides important observational evidence for the existence of SCS abyssal cyclonic circulation. Detailed spatiotemporal structure of abyssal circulation and its variations are presented, and related dynamic processes are discussed.

Background To describe the outcomes of in-bag extraction tissue through the middle part incision of posterior vagina in laparoscopic myomectomy.Methods This was a retrospective study of patients with laparoscopic myomectomy who underwent the middle part incision of posterior vagina to extraction tissue in bag between January 2016 and December 2022. We collected and analyzed data about patients’ characteristics, main indication for surgery, and intra- and postoperative complications.There were 37 cases of vaginal delivery of pregnant women after operation, and there was no laceration of the incision of the posterior wall of the vagina after delivery.Results A total of 511women underwent transvaginal specimen retrieval after laparoscopic myomectomy (mean largest myoma diameter: 8.44 ± 3.56cm; mean specimen weight: 789.23 ± 276.97g; mean operative time: 129.01 ± 53.13minutes; mean blood loss: 175.99 ± 210.96 mL). Within 30-days, no fever, infection, or vaginal bleeding, and the vaginal incisions healed well after 30 days of outpatient review.There was no incisional hernia, pelvic infection and vaginal adhesions during follow-up 3 months after operation.Conclusions The middle part incision of posterior vagina and in-bag transvaginal extraction can be considered a feasible technique at laparoscopic myomectomy.

Mammary gland microbiota is closely related to the progression of breast cancer (BC). Recent studies have shown that Listeria is differentially enriched in breast cancer and normal paracancerous breast tissue, and associated with epithelial-mesenchymal transition (EMT) in breast cancer. However, studies have rarely reported the relationship between Listeria monocytogenes (L. monocytogenes) enrichment and clinical parameters and possible mechanisms in breast cancer. In this study, we found that L. monocytogenes was highly enriched in the cytoplasm of cells, especially in tumor tissues. By analyzing the relationship between L. monocytogenesenrichment and the clinicopathological indicators and prognostic survival of patients, we found that L. monocytogenes is positively correlated with BC proliferation, metastasis, and poor recurrence-free survival (RFS) on patients. Moreover, we performed cell proliferation and invasion assays on breast cancer cells bearing L. monocytogenes, and proved that L. monocytogenes was able to promote the proliferation and invasion of breast cancer cells, their proliferation and invasion capacity was significantly reduced after antibiotic treatment. Mechanistically, L. monocytogenes was identified to increase the survival rate of circulating breast cancer cells by implementing the fluid shear stress model. In conclusion, our study demonstrated that L. monocytogenes could promote breast cancer development by increasing survival rate of circulating cancer cells.

The recycling and reutilization of cotton waste are in line with the sustainable development of society. Therefore, in this work, an environmentally friendly cellulose phosphate ammonium salt was synthesized by phosphorylation of cotton waste. Then the cotton fabrics were modified with cellulose phosphate ammonium salt by using the dip–dry–cure technique to obtain flame-retardant cotton fabric. The surface morphology, characteristic functional groups, and elemental components were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results indicated that the cellulose phosphate ammonium salt was immobilized onto the cotton fabric through a P–O–C chemical bond. Vertical combustion tests before and after washing showed that the treated cotton fabric had durable flame-retardant properties. Thermogravimetry demonstrated that the treated cotton fabric retained a large amount of residual char and the pyrolysis temperature was significantly earlier than that of the control sample. Compared with the blank sample, the peak of heat release rate and total heat release of the modified fabric was reduced by 90.8% and 84.1%, respectively. Thermogravimetric infrared of flame-retardant cotton fabric proved that cellulose phosphate ammonium salt acted both in the gas and condensed phase during the decomposition of the treated fabric.

In this paper, the lunar soil simulant parameters were calibrated using the discrete element method (DEM) for accurate simulation of the interactions between rover wheel and lunar soil simulant. Plackett-Burman, steepest ascent, and Box-Behnken experiments were utilized to propose a parameter calibration methodology. Firstly, the Plackett-Burman experiment was adopted to verify the influences of the nine parameters on the angle of repose (AoR), while three parameters with the most significant effects were identified according to their contributions, and the steepest ascent experiment narrowed their range. Then, the Box-Behnken experiment was utilized for their calibration and obtaining their optimal values. In the simulation, the Hertz–Mindlin (with JKR) contact model was chosen as the contact model. Finally, the calibrated DEM parameters were employed to perform the AoR validation test. The relative error between the simulation and experimental results was 3.4%. The penetration tests were then accomplished further to verify the accuracy and validity of DEM parameters. The penetration resistance curves in the simulation were compatible with the experiment. The obtained results can be utilized for future studies on the interaction between the rover wheel and soil.

A novel phosphorus- and nitrogen-containing flame retardant (APNTHE) was synthesized through the reaction of N, N, N′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, phosphoric acid and urea. Then, the APNTHE solution with a concentration of 120 g/L was used for the preparation of flame retardant cotton (FR-cotton). The elemental compositions, surface morphology, thermal stability and combustion behavior of the cotton before and after modification were investigated. Thermogravimetric (TG) analysis showed that the char residue of the treated fabric at 800°C was as high as 35.09% under a nitrogen atmosphere. Flammability tests after different LCs indicated that FR-cotton had durable flame retardancy. Compared to the blank sample, the peak of heat release rate and total heat release of the FR-cotton decreased by 91.89% and 90.53%, respectively. The char residual and TG-Fourier transform infrared spectroscopy analysis illustrated that APNTHE played a flame retardant role both in the gas phase and the condensed phase. All the results demonstrated that APNTHE can be regarded as a prospective flame retardant for cotton.

The EAZS shows high-performance features even in a wide-temperature range, such as widened voltage window, high energy/power density and ultralong cycle life. Its energy state is visually estimated by color transitions during charging/discharging.

To give silk fabric multiple functions and improve its application range, a facile and eco-friendly one-pot technique was used to endow silk fabric with dyeing, flame retardant and ultraviolet (UV)-resistant performance based on a safflower yellow derivative. The structure, surface morphology, elemental composition, thermal properties and combustion behavior of the silk samples before and after modification were all characterized. In addition, the color depth and color fastness of the dyed silk (D-silk) and flame retardant silk (FR-silk) were evaluated and measured. The positive

Based on subsurface mooring observations and HYCOM data, a complete investigation was conducted of the near-inertial waves (NIWs) caused by Typhoon MITAG to the east of Taiwan. HYCOM data were mainly used to reveal the role played by anticyclonic eddies in the propagation of NIWs. The results show that most typhoon-generated NIWs propagate towards negative vorticity, and NIWs near the edge gradually accumulated towards the eddy center and down to 800 m. NIWs propagating through the thermocline to the deep ocean were mainly concentrated in the eddy, and the near-inertial energy flux showed a significant enhancement from 400 to 600 m. Moreover, the downwards propagation of NIWs in the eddy enhanced the kinetic energy of background flow. NIWs outside the anticyclonic eddy dissipated quickly, while inside the eddy, there were high value areas of e-folding time. Dynamic mode decomposition illustrates that the anticyclonic eddy mainly captures higher modes of NIWs, and the state of continuous energy growth of higher modes can be maintained for more than a week. In addition, NIWs can also be carried westwards by the advection of the mean background flow at the eddy’s edge.

Surface and Subsurface currents in the Philippine Sea have been reported previously, and the debate persists regarding whether they are related to the strength of ENSO (El Niño/Southern Oscillation). We investigated the mean vertical structure and variability of the currents along the western boundary of the Philippine Sea using mooring observations at about 8°N, 127°E from August 2014 to January 2016. The southward Mindanao Current (MC) exists in the upper 600 m countered by the northward Mindanao Undercurrent (MUC) observed below 600 m to the depth of 2,000 m, with a core at approximately 1,000 m. During the development of El Niño from July to December 2015, the core velocity and depth of the MC were noticeably increased, consistent with the Niño 3.4 index, and the current at 2,000 m was observed to be southward, which indicated that the MC may extend to 2,000 m under the influence of El Niño. The MUC was stronger around November 2015, corresponding to the peak phase of the Niño 3.4 index. The intraseasonal variability with a period of 70-110 days from the surface to 2,000 m is also discussed based on power spectral analysis. Subsurface eddies are likely the source of the intraseasonal variability of current in the Philippine Sea from the model outputs.

Mesoscale eddies are widespread in the oceans; however, tracking and observing them remains a challenge. Additionally, there are few studies of eddy–Kuroshio interactions based on large-scale in situ data. Data from a large array of 39 CPIESs deployed around the Luzon Strait in 2018–2019 (12 deployed east of Taiwan within a 3 × grid) were used to reveal the three-dimensional structure of mesoscale eddies and their interaction with Kuroshio. The results show a strengthening (weakening) of the tilt of the pycnocline, which has also caused a deeper (shallower) pycnocline in eastern Taiwan following an anticyclonic (cyclonic) interaction with Kuroshio, which resulted in a strengthening (weakening) of the Kuroshio. During the anticyclonic eddy impinging Kuroshio, the downward (upward) movement at the center of the anticyclonic eddy (Kuroshio) results in a positive (negative) anomaly structure for temperature, with corresponding positive (negative) anomalies for salinity above 600 m in the intermediate layer and negative (positive) anomalies below 600 m. In contrast, when the cyclonic eddies interact with the Kuroshio, the temperature and salinity anomalies change simultaneously, with the temperature showing an overall negative anomaly and the salinity showing a negative and positive anomaly above and below 600 m, respectively. The research in this study provides the basis for further research on energy exchange during eddy–Kuroshio interactions.

In order to obtain 3D printed alumina ceramic cores with isotropic shrinkage, a pore former was added into the photocurable slurry, and combined with an optimization of the sintering procedure. Micron scale pores were observed in the sintered ceramics when the pore former was present compared with the samples without pore former. The addition of the pore former significantly improved the pore interconnectivity and pore size of the 3D printed ceramics, due to the volatilization of the pore former. The resulting shrinkage of the ceramic parts in three directions was more uniform and smaller when they were fabricated using a slurry containing the pore former in comparison to those without pore former. The bulk density, shrinkage, and flexural strength of the ceramics increased with increasing the sintering temperature. Triple sintering significantly improved the flexural strength, and also lead to anisotropic shrinkage of the samples, due to the enhanced binding force between layers deriving from the increased number of sintering cycles. In addition, the triple sintering process enabled healing of the cracks developed during sintering, differently from a single sintering. The use of a pore former and the triple sintering procedure provides a new optimized strategy for the fabrication of 3D printed ceramic cores with suitable properties.

The design of electrocatalysts with high activity and the understanding of the reaction mechanism for the ethanol oxidation reaction (EOR) are pivotal for commercializing direct ethanol fuel cells (DEFCs). Herein, island-like nanoporous gold/palladium (INPG/Pd) is designed as a highly efficient EOR electrocatalyst. For a better understanding of the reaction mechanism

Cancer pain is the most prevalent symptom experienced by cancer patients. It substantially impacts a patient’s long-term physical and emotional health, making it a pressing issue that must be addressed. Purinergic receptor P2X7 (P2X7R) is a widely distributed and potent non-selective ATP-gated ion channel that regulates tumor proliferation, chronic pain, and the formation of inflammatory lesions in the central nervous system. P2X7R plays an essential role in cancer pain and complications related to cancer pain including depression and opioid tolerance. This review focuses on the structure and distribution of P2X7R, its role in diverse tissues in cancer pain, and the application of P2X7R antagonists in the treatment of cancer pain to propose new ideas for cancer pain management.

Bone cancer pain (BCP) is the most severe and intractable type of cancer pain. Emerging evidence has demonstrated that activated microglia in the spinal cord could release a series of neurotoxic substances to stimulate neurons and form neuronal sensitization. The P2X7 receptor (P2X7R) is a nonselective ATP-gated ion channel predominantly present in microglia in the spinal cord as the key modulator of microglial activity. However, the specific effect and underlying molecular mechanism of P2X7R in BCP have not yet been elucidated.This study aimed at investigating whether P2X7R-induced BCP by regulating microglial activity through NLRP3/IL-1beta signaling involvement in BCP.Controlled animal study.A BCP animal model was established by injecting Walker-256 breast cancer cells into the tibia of female rats. Fifty percent paw withdrawal thresholds (50% PWTs), number of spontaneous flinches (NSF), and limb use scores were used to evaluate behavior in rats. P2X7R inhibitor brilliant blue G (BBG) was used to assess the role of P2X7R in BCP-induced NLRP3 inflammasome activation. Western blot, RT-PCR, and immunofluorescence were used for quantitative comparison. In vitro, BV2 cells were treated with lipopolysaccharide (LPS) and BzATP, in the presence or absence of P2X7 siRNA, with nigericin (an agonist of the NLRP3 inflammasome) to further study the mechanism of P2X7R regulate NLRP3/IL-1beta signaling.The inhibition of spinal P2X7R with BBG could effectively inhibit BCP due to suppressing the expression of NF-kappaB p-p65, NLRP3 inflammasome formation, and downstream pain factors IL-1beta. Furthermore, P2X7 siRNA could reduce microglial activity, the nuclear translocation of NF-kappaB, and the synthesis of NLRP3 and IL-1beta in BV2 cells. In addition, nigericin partially reversed the ameliorating effect of P2X7 siRNA on BV2 cells induced by LPS and BzATP.BBG could relieve BCP but not improve the destruction of bone, which may be related to the specificity of inoculated cells. Further mechanisms should be investigated.These findings suggest that targeting the microglial P2X7R activated NLRP3/IL-1beta signaling pathway could serve as a potential strategy for BCP treatment.

This study aims to evaluate the in vitro antibacterial and anti-biofilm activities of licochalcone A on Enterococcus faecalis and to investigate the possible target genes of licochalcone A in E. faecalis. This study found that licochalcone A had antibacterial activities against E. faecalis, with the MIC50 and MIC90 were 25 μM. Licochalcone A (at 4 × MIC) indicated a rapid bactericidal effect on E. faecalis planktonic cells, and killed more E. faecalis planktonic cells (at least 3-log10 cfu/ml) than vancomycin, linezolid, or ampicillin at the 2, 4, and 6 h of the time-killing test. Licochalcone A (at 10 × MIC) significantly reduced the production of E. faecalis persister cells (at least 2-log10 cfu/ml) than vancomycin, linezolid, or ampicillin at the 24, 48, 72, and 96 h of the time-killing test. Licochalcone A (at 1/4 × MIC) significantly inhibited the biofilm formation of E. faecalis. The RNA levels of biofilm formation-related genes, agg, esp, and srtA, markedly decreased when the E. faecalis isolates were treated with licochalcone A at 1/4 × MIC for 6 h. To explore the possible target genes of licochalcone A in E. faecalis, the licochalcone A non-sensitive E. faecalis clones were selected in vitro by induction of wildtype strains for about 140 days under the pressure of licochalcone A, and mutations in the possible target genes were detected by whole-genome sequencing. This study found that there were 11 nucleotide mutations leading to nonsynonymous mutations of 8 amino acids, and among these amino acid mutations, there were 3 mutations located in transcriptional regulator genes (MarR family transcriptional regulator, TetR family transcriptional regulator, and MerR family transcriptional regulator). In conclusion, this study found that licochalcone A had an antibacterial effect on E. faecalis, and significantly inhibited the biofilm formation of E. faecalis at subinhibitory concentrations.

The leading cause of many respiratory diseases is an ongoing and progressive inflammatory response. Traditionally, inflammatory lung diseases were studied primarily through animal models, cell cultures, and organoids. These technologies have certain limitations, despite their great contributions to the study of respiratory diseases. Precision-cut lung slices (PCLS) are thin, uniform tissue slices made from human or animal lung tissue and are widely used extensively both nationally and internationally as an in vitro organotypic model. Human lung slices bridge the gap between in vivo and in vitro models, and they can replicate the living lung environment well while preserving the lungs’ basic structures, such as their primitive cells and trachea. However, there is no perfect model that can completely replace the structure of the human lung, and there is still a long way to go in the research of lung slice technology. This review details and analyzes the strengths and weaknesses of precision lung slices as an in vitro model for exploring respiratory diseases associated with inflammation, as well as recent advances in this field.

Recently, thermophilic Thermoanaerobacterium species have attracted increasing attentions in consolidated bioprocessing (CBP), which can directly utilize lignocellulosic materials for biofuels production. Compared to the mesophilic process, thermophilic process shows greater prospects in CBP due to its relatively highly efficiency of lignocellulose degradation. In addition, thermophilic conditions can avoid microbial contamination, reduce the cooling costs, and further facilitate the downstream product recovery. However, only few reviews specifically focused on the microbial applications of thermophilic Thermoanaerobacterium species in lignocellulosic biorefinery. Accordingly, this review will comprehensively summarize the recent advances of Thermoanaerobacterium species in lignocellulosic biorefinery, including their secreted xylanases and bioenergy production. Furthermore, the co-culture can significantly reduce the metabolic burden and achieve the more complex work, which will be discussed as the further perspectives. KEY POINTS: • Thermoanaerobacterium species, promising chassis for lignocellulosic biorefinery. • Potential capability of hemicellulose degradation for Thermoanaerobacterium species. • Efficient bioenergy production by Thermoanaerobacterium species through metabolic engineering.

Ammonium salt of diethylene triamine penta methylene phosphonic acid (ADTPMPA), a novel flame retardant, was synthesized and grafted on the lyocell fabric to obtain a kind of flame retardant lyocell fabric (FR-lyocell). Then FR-lyocell was coated by Ag nanoparticles (Ag NPs) to fabricate flame retardant and antibacterial lyocell fabric (FR-Ag-lyocell). The elemental composition, surface morphology, combustion behavior and antibacterial activity of the lyocell fabric before and after modification were investigated. The flame retardant and antibacterial mechanism of FR-Ag-lyocell fabric was also analyzed. The limiting oxygen index (LOI) values of FR-Ag-lyocell fabric before and after 20 laundering cycles (LCs) reached 44.8% and 31.3%, respectively. The treated lyocell fabric possessed lower peak of heat release rate (pHRR) and total heat release (THR) values compared with control lyocell fabric. The FR-Ag-lyocell fabric exhibited excellent antimicrobial ability against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), even after 10 LCs. These results indicated that FR-Ag-lyocell fabric had durable flame retardant and antibacterial properties.

A novel effective halogen-free flame retardant (FR) rich in phosphorus (P) and nitrogen (N) was synthesized via Mannich and esterification reaction of ethanolamine, glyoxal, phosphoric acid and urea, and used for the preparation of durable flame retardant lyocell fabric (FR-lyocell). Its chemical structure was characterized by Fourier transform infrared spectra, 1H and 31P nuclear magnetic resonance spectra. Inductively coupled plasma emission spectrometry and elemental analysis were conducted to test the phosphorous, carbon and nitrogen contents. The results confirmed that the FR was successfully synthesized and grafted on the lyocell fabric via firm P–O–C covalent bonds. The limiting oxygen index of the FR-lyocell treated with 30 wt% flame retardant finishing solution is 44.6%, demonstrating high efficiency flame retardancy. The thermo-gravimetric analysis indicated that FR-lyocell degraded preferentially than that of the control sample and the char residue was 38.8 wt% at 800 °C in N2 atmosphere. In addition, the cone calorimeter test revealed that FR-lyocell could not be ignited and the peak of heat release rate was much lower than that of original specimen. Furthermore, the char residue of FR-lyocell is compact and the ID/IG value is 0.771, exhibiting a super degree of carbonization. Moreover, TG-IR result revealed that FR played dual flame-retardant effect in the gaseous and condensed phases. The flame retardant finishing has a negligible impact on the mechanical properties of the fibers. In summary, FR-lyocell exhibits excellent flame retardancy and superior char forming capability, which is suitable for the preparation of flame retardant lyocell fibers.

Stereolithography based-3D printing technology requires ceramic slurries with high solid content and low viscosity to prevent the formation of cracks, holes, warping, and other defects in sintered ceramic parts. In this study, several approaches based on optimization of alumina powder and coupling agent were explored to improve the solid content of ceramic slurries. It was shown that slurries containing γ-Al2O3 reached solid content of only 22.5 wt% and viscosity of 15,199 mPa·s. By comparison, slurries composed of α-Al2O3 reached higher solid content of 75 wt% and viscosity of 12,780 mPa·s. Three types of coupling agents, namely (3-Aminopropyl) triethoxysilane, (Aminoethylamino) propyldimethoxymethylsilane and 3-(Trimethoxysilyl) propyl methacrylate (abbreviated as E, F and G, respectively) were used to reduce the viscosity of the slurries. The addition of 10 wt% G led to slurry solid content reaching 82 wt% and viscosity of 860 m·Pas. The significant decrease in viscosity was mainly attributed to the presence of bifunctional hydrolyzable groups in G, which could well attach to alumina. On the other hand, the presence of organo-functional groups might also well attach to the photosensitive resin. The ceramics prepared with γ-Al2O3 exhibited numerous pores in both intraparticle and intergranular while those obtained with α-Al2O3 showed pores in only intergranular. The porous structure in γ-Al2O3 occupied large space, leading to low solid content. Ceramics prepared with 75 wt% solid content possessed flexural strength of 29.3 MPa, bulk density of 2.3 g/cm3 and open porosity of 39.8 %. By comparison, ceramics prepared with 82 % solid content showed flexural strength of 45.0 MPa. In sum, these findings look promising for future preparation of high-solid content 3D printed ceramic slurries for complex ceramics, such as ceramic cores.