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C18H19N5, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 6.612(4) Å, b = 8.800(5) Å, c = 13.777(8) Å, α = 83.219(7)°, β = 79.329(6)°, γ = 78.744(6)°, V = 769.8(8) Å3, Z = 2, R gt(F) = 0.0394, wR ref(F 2) = 0.0996, T = 100(2) K.

The actual tooth surface is hardly obtained utilizing the existing simulation machining method. Therefore,a highprecision simulation machining method for gear shaping is proposed. Based on the CATIA platform,the spatial motion relationship between the cutter and the gear blank is analyzed by establishing the model of the cutter and the gear blank. The high-precision insertion of the cylindrical spur gear is completed considering the commands of CATIA translation,rotation,Boolean operation and secondary development functions. The tooth surface accuracy is confirmed with the actual processing parameters by measuring the normal distance between the standard involute and the tooth surface of the simulation model. Finally,the simulation model is reconstructed. The simulation model and the reconstruction model are separately solved by finite element. By comparing the simulation model and the reconstruction model solution results,the effectiveness of the simulation model obtained by this method is verified.

Zn2C8H32N4O16S4${\text{Zn}}_{2}{\text{C}}_{8}{\text{H}}_{32}{\text{N}}_{4}{\text{O}}_{16}{\text{S}}_{4}$, triclinic, P1‾$P‾{1}$ (no. 2), a = 9.0313(9) Å, b = 9.6075(14) Å, c = 15.3044(15) Å, α = 89.933(2)°, β = 78.579(1)°, γ = 68.878(1)°, V = 1210.6(2) Å3, Z = 2, Rgt${R}_{gt}$(F) = 0.0323, wRref$w{R}_{\mathit{ref}}$(F2) = 0.1043, T = 100(2) K.

A late-model all-fiber mode-locked laser was introduced in this paper. This pulsed Er-doped fiber laser has a novel Sagnac loop structure and uses the tapered fiber coated with two-dimensional layer ferromagnetic insulator Cr2Si2Te6 as a saturable absorber in order to achieve passive mode locking. When the pump power was 167.6 mW, the laser worked at the fundamental repetition frequency of 19.1 MHz with a signal-to-noise ratio of 62.5 dB. The central wavelength of the spectrum was 1561.0 nm, and the maximum output power was 8.9 mW with a minimum pulse width of 5.2 ps. The mutual interference of beams makes the use of the saturable absorber more efficient. The results reveal that this Er-doped fiber laser has great application potential in nonlinear optics and ultrafast photonics. [ABSTRACT FROM AUTHOR]

To improve the surface quality of natural diamond grinding, the ultrasonic vibration was introduced for composite grinding, and an inelastic collision theory model was established to calculate the amplitude of ultrasonic vibration. The effects of ultrasonic amplitude, grinding speed and grinding grain size on the material removal of natural diamond (100) crystal surface were studied, and the optimal process parameters were sought. The results show that the ultrasonic amplitude ranges from 3.1 to 8.7 µm in the direction of easy grinding of natural diamond (110) crystal surface and 2.9 to 9.1 µm in the direction of easy grinding of natural diamond (100) crystal surface. The optimal process combination parameters of natural diamond (100) crystal surface grinding obtained by orthogonal experiment are ultrasonic amplitude of 6.0 µm, grinding disk speed of 2 800 r/min, diamond grinding grain size code of M3/6. The surface roughness Ra of diamond (100) crystal surface after ultrasonic assisted grinding is 16.21 nm, which is 63.83% lower than that of traditional mechanical grinding. Ultrasonic assisted grinding of natural diamonds can achieve better surface quality than traditional mechanical grinding. [ABSTRACT FROM AUTHOR]

Brazilin possesses anticancer effects, but the mechanisms are poorly understood. This study investigated the mechanisms of brazilin‐induced cell death in the T24 human bladder cancer cell line. Low serum cell culture and the lactate dehydrogenase assay were used to confirm the antitumor effect of brazilin. Annexin V and propidium iodide double staining, transmission electron microscopy, fluo‐3‐AM assay for Ca2+ mobilization and caspase activity assay were performed to identify the type of cell death after brazilin treatment. Mitochondria membrane potentials were measured using JC‐1. Quantitative real‐time polymerase chain reaction and western blot analyses were performed to verify the expression of the necroptosis‐related genes and proteins receptor interacting protein 1 (RIP1), RIP3 and mixed lineage kinase domain‐like (MLKL). The results showed that brazilin induced necrosis in T24 cells and upregulated the mRNA and protein levels of RIP1, RIP3 and MLKL and Ca2+ influx. The necroptosis‐mediated cell death was rescued by the necroptosis inhibitor necrostatin‐1 (Nec‐1), but not by the apoptosis inhibitor z‐VAD‐fmk. Brazilin repressed caspase 8 expression and decreased the mitochondrial membrane potentials; both effects were partially reversed by Nec‐1. Brazilin induced physiological and morphological changes in T24 cells and RIP1/RIP3/MLKL‐mediated necroptosis might be involved. In conclusion, the results confirm the involvement of necroptosis in brazilin‐induced cell death and suggest that brazilin could be explored as an anticancer agent against bladder cancer. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) semiconductors are being considered as alternative channel materials as silicon-based field-effect transistors (FETs) have reached their scaling limits. Recently, air-stable 2D selenium nanosheet FETs with a gate length of 5 µm were experimentally produced. In this study, we used an ab initio quantum transport approach to simulate sub-5 nm gate-length double-gate monolayer (ML) selenene FETs. When considering negative-capacitance technology and underlap, we found that 3 nm gate-length p-type ML selenene FETs can meet the 2013 ITRS standards for high-performance applications along the armchair and zigzag directions in the 2028 horizon. Therefore, ML selenene has the potential to be a channel material that can scale Moore's law down to a gate length of 3 nm. [ABSTRACT FROM AUTHOR]

Semiconductors with low dimensions have been presented when field-effect transistors (FETs) using silicon as a channel material approach their limits related to scale. Recently, 5 μm gate length selenium nanosheet FETs have been experimentally fabricated. An approach called ab initio quantum transport is implemented in this work to investigate the efficiency of sub-5 nm gate length gate-all-around (GAA) selenium nanowire FETs. The performances of the sub-5 nm gate length n-type GAA selenium nanowire FETs are superior to those of the p-type ones. Given the negative capacitance technology and underlap, the efficiency of 1 nm gate length n-type GAA selenium nanowire FETs could meet the benchmarks of the 2013 ITRS concerning usage related to high performance (HP) and low power (LP) in the perspective of 2028. Therefore, selenium nanowires are a suitable channel material of FETs that can extend Moore's law to 1 nm, making ultrashort selenium nanowires applicable for nanoelectronics. [ABSTRACT FROM AUTHOR]