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Objective: To evaluate the diagnostic performance of galactomannan (GM) detection in serum and bronchoalveolar lavage fluid (BALF) for invasive pulmonary aspergillosis (IPA) in non-neutropenic patients. Methods: A total of 291 non-neutropenic patients in the Second Xiangya Hospital of Central South University were included. According to the 2019 EORTC/MSG guidelines, all cases were divided into an IPA group (n = 24) and a non-IPA group (n = 267). Receiver operating characteristic (ROC) curves were drawn to compare the diagnostic efficiency of GM detection in BALF and serum. Results: According to the receiver operating characteristic curves of BALF and serum GM, the areas under the curve were 0.961 and 0.699, respectively. The optimal BALF GM detection was found when the cutoff value was set to 0.87, whereas the sensitivity and specificity were 91.7% and 92.5%, respectively. Conclusions: BALF GM detection is more sensitive than serum GM detection for diagnosing IPA, and the optimal cutoff value for BALF GM is 0.87. [ABSTRACT FROM AUTHOR]

In this work, a stereolithography-based method of 3D printing was successfully used to fabricate a complex-shaped triangular zirconia cutting tool with a tool withdrawal groove and a honeycomb ceramic component. The sintered bodies displayed significant shrinkage after sintering, with the maximum shrinkage being 35.26%. The XRD pattern indicated that the crystalline phase of the parts was the t-ZrO 2 phase, while SEM characterization revealed that the sintered bodies were composed of densely packed submicron-grade grains, without any discernible pores. The density of the parts was measured as 97.14% via Archimedes’ water displacement method, which is consistent with the results of SEM characterization. Additionally, the measured Vickers hardness and fracture toughness of the fabricated parts were 13.0597 GPa and 6.0380 MPa m 1/2 , respectively. These values are close to the structural properties of common zirconia ceramics prepared by conventional approaches. Hence, a novel DLP-stereolithography-based 3D printing process for the fabrication of complex and dense zirconia ceramic parts has been proposed in this work. [ABSTRACT FROM AUTHOR]

Experimental results of the thickness and velocity distribution of the vertical falling film of a gas–liquid two-phase flow in a scrubbing-cooling tube are reported. The liquid Reynolds numbers ranges from 1.0 × 10 4 to 3.1 × 10 4 . A 3D numerical model of the scrubbing-cooling ring and tube has also been established. The simulation results agree well with the experimental data. The research shows that the average liquid film thickness is largest at the 0° circumferential position. A part of the liquid is separated from the local liquid film and drips in the gas core when Reynolds number ≥ 1.5 × 10 4 . Circumferentially the liquid film thickness is distributed more evenly in the lower section of the tube. When the liquid Reynolds number increases, both of the global liquid film thickness and velocity increase, and the thickness distribution becomes unevener. The liquid film velocity increases with the increase of flow distance at small Reynolds number and decreases at large Reynolds number. [ABSTRACT FROM AUTHOR]

• The mean thickness of the turbulent liquid film falling down a vertical plat can be divided into three regions. • Relationships between the liquid film instantaneous thickness and Re l were discussed. • The distribution of the liquid film thickness tends to an approximately normal distribution with increasing Re l. • The fluctuation range of the liquid film instantaneous thickness will approach a fixed value as the Re l increases. The wave characteristics of the turbulent falling liquid film in the development region along the vertical Perspex plate were studied by using an Ultrasonic Doppler Velocimetry (a non-intrusive technique). The instantaneous thickness of the falling film at the center of the plate with axial distance ranges from 50 mm to 1300 mm was measured and the Re l (the liquid film Reynolds number) ranges from 2.28 × 103 to 1.43 × 104. The results show that the mean thickness, wave frequency and amplitude increase while the growth rate decreases with the increase of Re l. The Probability Density Function of the liquid film instantaneous thickness tends to an approximately normal distribution with increasing Re l. Furthermore, the Plateau-Rayleigh instability can cause the breakup of the liquid film surface and resist the increase of the liquid film thickness, which results in the fluctuation range of the liquid film approximate to a fixed value when the Re l > 1.20 × 104. [ABSTRACT FROM AUTHOR]

Abstract: Decomposition of aquatic plant litters is an important process in ecological system, which will significantly affect the water environment and internal organisms. In this study, cattail litter was added into surface flow constructed wetland (SFCW) system to utilize as the additional carbon source for denitrification process. The adding method for the litter was determined by evaluating the influence of different adding methods on the water environment (pH, dissolved oxygen) and the litter utilization efficiency. Then, the change of effluent organic concentration (total organic carbon, TOC) and nitrogen removal efficiency of the system was investigated after the litter addition, meanwhile, the microbial community change was analyzed by high-throughput sequencing. The results showed that cattail litter should be added in batches to the SFCW system with the dosage of 0.1 g L−1 d−1, and the TN removal and loading of the system were significantly increased without obvious increase of the effluent TOC. After the litter addition, summer had higher increasing level of the denitrification efficiency of the system, which was lower in winter. This study could provide suitable method for cycling utilization of aquatic plant litters, and improve the denitrification effect of SFCW system. Graphical abstract Image 1 Highlights • Cattail litter as carbon source for denitrification process in SFCW system. • The litter should be added in batches (dosage of 0.1 g L−1 d−1) into the system. • Nitrogen removal of the SFCW system was significantly enhanced with litter addition. • Dechloromonas content for denitrification was greatly increased with litter addition. [ABSTRACT FROM AUTHOR]

In the authors’ prior works, the microstructure, turning cutting performance and wear mechanisms of PVD-CrAlN and TiAlN coated silicon nitride cutting inserts on turning of gray iron were studied. In the present work, based on the authors’ former study, the effects of the cutting speed on tool life, wear mechanism and surface quality of the workpieces were studied through high speed face milling tests. The uncoated, CrAlN and TiAlN coated cutting inserts were conducted by high speed face milling of gray iron at various cutting speeds of 600 m/min~1500 m/min. The results displayed that during high speed face milling, the tool life of the PVD coated Si 3 N 4 cutting inserts decreased as the cutting speed increased. When the cutting speed reached a certain value, the tool life increased with the cutting speed increasing. During high speed face milling, no spallation failure happened to both CrAlN and TiAlN coatings, and the coatings could protect the insert substrates effectively under various cutting speeds, improving the tool life of the uncoated cutting inserts by 138–150% and 32–65%, respectively. The wear mechanisms of all three kinds of the cutting inserts by face milling of gray iron under various cutting speed were the same. The only difference was that as the cutting speed increased, the adhesive wear of the inserts increased significantly. During high speed face milling of gray iron with three kinds of inserts, the alteration relationship of machining quality with the cutting speed was similar to the tool life with the cutting speed relationship. Furthermore, when high speed face milling of gray iron was conducted, CrAlN coated Si 3 N 4 cutting inserts displayed the best machining quality, followed by TiAlN coated and the uncoated inserts, respectively. [ABSTRACT FROM AUTHOR]

In this work, CrAlN and TiAlN coatings were produced on silicon nitride cutting inserts via physical vapor deposition. The microstructure and hardness of the coatings, as well as the adhesive strength between the coating and the substrate were studied using a scanning electronic microscope, a micro hardness tester and a scratch tester, respectively. Continuous turning tests of the obtained CrAlN and TiAlN-coated silicon nitride cutting inserts were performed on gray cast iron to evaluate the cutting performances and the machining quality. The results show that the surface hardness of the Si 3 N 4 cutting inserts could be improved by 87% and 50%, respectively, when applying the CrAlN and TiAlN coatings, thereby enhancing the abrasion resistance of the cutting inserts. At different tested cutting speeds, abrasive wear under compressional deformation and adhesive wear were identified as the main failure mechanisms for the two cutting inserts during continuous turning of gray cast iron. The machining quality of the gray cast iron workpieces machined using the uncoated, the CrAlN- or the TiAlN-coated inserts increased with the increment of the cutting speed. [ABSTRACT FROM AUTHOR]

We report a novel approach to fabricate dense zirconia-toughened alumina (ZTA) ceramics with excellent properties via an additive manufacturing process based on stereolithography. The XRD patterns show the ZTA sample consists of α-Al 2 O 3 and t-ZrO 2 with the dominance of α-Al 2 O 3 . The zirconia grain with the average size of 0.35 µm is small enough to trigger the toughening behavior of zirconia in the ZTA. The prepared ceramics showed a density, Vickers hardness, bending strength, and fracture toughness of 4.26 g/cm 3 , 17.76 GPa, 530.25 MPa, and 5.72 MPa m 1/2 , respectively. These properties are comparable to those for ceramics obtained through conventional ceramic processing. [ABSTRACT FROM AUTHOR]

In this study, we report a novel approach, integrating stereolithography and liquid precursor infiltration techniques, to fabricate fine-grained alumina ceramics. The XRD patterns of the sample immersed with Zr 4+ or Zr 4+ (Y 3+ ) show that the sintered body contains Al 2 O 3 and t-ZrO 2 as the major phase and minor phase, respectively. Moreover, the t-ZrO 2 phase in the sample immersed with Zr 4+ (Y 3+ ) shows intense peaks compared to the composite immersed with Zr 4+ . On the other hand, the sample immersed with Mg 2+ contained Al 2 O 3 and MgAl 2 O 4 as the major phase and minor phase, respectively. The microstructure of the sample immersed with Zr 4+ shows that ZrO 2 particles are homogeneously distributed in the Al 2 O 3 matrix, thus inhibiting the grain growth of alumina particles. Moreover, the sample immersed with Mg 2+ shows a more dense and fine-grained structure. Compared to the non-infiltrated sample, the average grain size of the alumina sample immersed with Zr 4+ or Mg 2+ decreased. The sample infiltrated with Zr 4+ (Y 3+ ) had the smallest alumina average grain size of 1.14 µm. The ceramics prepared by infiltration showed a higher hardness (19.54 GPa), but a slightly lower fracture toughness (4.02 MPa m 1/2 ) compared to the samples (17.2 GPa, 4.13 MPa m 1/2 ) without infiltration. [ABSTRACT FROM AUTHOR]