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Objective Methods Forty adult periodontitis patients were involved(twenty in the test group and twenty in the control group, randomly). All patients received systematic periodontal examination, recording and calculating percentage of sites with plaque, probing depth and bleeding on probing, and implement routine oral hygiene instruction at the first visit. The test group received additional plaque staining and individual oral hygiene instruction. Both groups completed supragingival scaling and polishing at the first visit. After 1 week, subgingival scaling and root planning were completed. After 6 weeks, re-evaluation was performed, and oral hygiene and periodontal clinical indicators were recorded and compared. Results The percentage of plaque in test group and control group decreased by (56. 21 ± 14. 64)% and (43. 82 ± 11. 01)% respectively after treatment; The percentage of calculus decreased by(33. 60 ± 11. 01)% and (21. 28 ± 11. 96)% respectively compared with that before treatment. There were also statistically significant differences in the percentage of plaque and calculus between the two groups before and after treatment(P＜0. 001). After treatment, the probing depth of the two groups decreased by (1. 61 ± 0. 96) mm and (0. 86 ± 0. 69) mm, respectively; The percentage of bleeding after probing in the two groups decreased by (49. 51 ± 14. 67) % and (36. 70 ± 15. 40) %, respectively, compared with that before treatment. There were also statistically significant differences in the probing depth and the percentage of bleeding on probing between the two groups before and after treatment, and between the two groups(P＜0. 001). Conclusion The auxiliary application of plaque staining is helpful to improve the oral health status of patients with periodontitis and the clinical performance of periodontal non-surgical therapy. T o evaluate the clinical effect of plaque staining-assisted routine oral health education on oral hygiene of and clinical performance of periodontal non-surgical therapy for patients with periodontitis. (目的 评估菌斑染色辅助常规口腔卫生宣教方法的临床效果。方法 选取40例拟行牙周基础治疗的成年牙周炎患者, 随机分入试验组和对照组, 各20例。首诊均接受系统牙周检查, 记录和计算菌斑、牙石百分比、探诊深度和探诊后出血并实施常规口腔卫生宣教。试验组额外应用菌斑染色并接受个性化口腔卫生指导。两组均于首诊完成龈上洁治和抛光, 1周后分区段完成龈下刮治和根面平整, 6周后进行再评估, 记录并对比口腔卫生情况和牙周临床指标。结果 治疗后试验组与对照组菌斑百分比较治疗前分别降低(56. 21±14. 64)%和(43. 82±11. 01)%; 牙石百分比较治疗前分别降低(33. 60±11. 01)%和(21. 28±11. 96)%, 两组菌斑和牙石百分比治疗前后的差异和两组间降低值的差异均有统计学意义(P＜0. 001)。治疗后两组探诊深度较治疗前分别降低(1. 61±0. 96) mm和(0. 86±0. 69) mm; 两组探诊后出血百分比较治疗前分别降低(49. 51±14. 67)%和(36. 70±15. 40)%, 两组探诊深度和探诊后出血百分比治疗前后的差异和两组间降低值的差异均有统计学意义(P＜0. 001)。结论 辅助应用菌斑染色有助于改善牙周炎患者的口腔卫生状况和牙周基础治疗疗效。)

A series of long-term high-temperature aging tests of ASME A335-P92 steel from 1,000 to 29,000 h at 650°C were carried out. The microstructure evolution of as-received and aging specimens at different stages was investigated using optical microscope observations, scanning electron microscope examinations, and TEM investigations. The static mechanical strength properties (yield strength/ultimate tensile strength) at room and 600°C test temperatures and the plastic performance (elongation/reduction in area) were also analyzed. The experimental results show that the Laves phase can be precipitated rapidly in the early aging period. After a certain aging period, the continuous precipitation of M23C6 and the relatively high coarsening rate of Laves resulted in a rapid decrease of room and high-temperature mechanical properties in the early aging period. However afterwards for the long aging time, a slow decline in tendency of mechanical properties was presented.

Herein, a novel enhancement-mode (E-mode) GaN-based p-channel FETs (p-FETs) with a linearly graded AlGaN (LGA) p-channel is proposed and numerically studied by Silvaco TCAD. Thanks to strong polarization-induced doping, three-dimensional hole gas (3DHG) can be uniformly generated in LGA to form a continuous p-channel with a hole concentration over 1018 cm–3. Combined with an optimized recessed gate structure, the LGA p-FET can simultaneously achieve a large threshold voltage (| V TH|) > 2 V and a high current density (| J DS|) of ∼10 mA mm−1 at V DS = −10 V. Additionally, two critical parameters of the LGA p-FETs, i.e. the depth of recessed gate and initial Al composition of LGA, are specifically studied to reveal the unique carrier behavior of 3DHG in the devices. Importantly, the LGA structure is further optimized and implemented as the p-type cap layer to construct an E-mode GaN n-FET. Thereby, based on the same LGA configuration, a GaN-based inverter with the matched complementary n- and p-FETs is monolithically constructed, showing sharp voltage transition. The reported novel LGA structure and its availability in both GaN-based E-mode n- and p-FETs provides valuable insights and guidance to construct highly efficient GaN p-type devices and All-GaN-based integrated circuits for compact power electronic systems. [ABSTRACT FROM AUTHOR]

Solvent molecules interact with a solute through various intermolecular forces. Here we employed a potential energy surface (PES) analysis to interpret the solvent‐induced variations in the strengths of dative (Me3NBH3) and ionic (LiCl) bonds, which possess both ionic and covalent (neutral) characteristics. The change of a bond is driven by the gradient (force) of the solvent‐solute interaction energy with respect to the focused bond length. Positive force shortens the bond length and increases the bond force constant, leading to a blue‐shift of the bond stretching vibrational frequency upon solvation. Conversely, negative force elongates the bond, resulting in a reduced bond force constant and red‐shift of the stretching vibrational frequency. The different responses of Me3NBH3 and LiCl to solvation are studied with valence bond (VB) theory, as Me3NBH3 and LiCl are dominated by the neutral covalent VB structure and the ionic VB structure, respectively. The dipole moment of an ionic VB structure increases along the increasing bond distance, while the dipole moment of a neutral covalent VB structure increases with the decreasing bond distance. The roles of the dominating VB structures are further examined by the geometry optimizations and frequency calculations with the block‐localized wavefunction (BLW) method. [ABSTRACT FROM AUTHOR]

In this paper, a novel hybrid triply periodic minimal surface (TPMS) core with a nonlinear transition region was designed by combining two types of TPMS (Diamond and Schwarz P) structures using the sigmoid function. The width of the transition region was precisely regulated by adjusting the gradient control parameter r in the sigmoid function. Composite sandwich structures (CSS) were fabricated by bonding two carbon fiber reinforced polymer (CFRP) face sheets to a 3D printed polylactic acid (PLA) core. The bending performance and failure mechanisms of the CSSs with the hybrid TPMS cores were analyzed through three-point bending tests and finite element analysis (FEA). The results indicate that as r increases, the transition region of the hybrid TPMS cores becomes narrower, leading to a gradual decrease in bending strength, bending stiffness, and core shear stress. The failure process of the CSSs in the experiment aligns well with the FEA results. Through comparative analysis of the stiffness-to-weight and strength-to-weight ratios of the CSSs with the native TPMS cores, the hybrid TPMS cores with a wider transition region enhance the structural efficiency of the CSSs, while those with a narrower transition region negatively impact the performance of the CSSs. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (CO2RR) converts the greenhouse gas CO2 into valuable chemicals under mild conditions and is considered a promising approach to reaching carbon neutralization. However, its efficiency and selectivity towards desired products remain far below the requirements for industrial implementation because of its complex reaction mechanism and diverse intermediates. Particularly, the C–C coupling step in the CO2RR is the key step to ensure a high yield of value-added multi-carbon products. Herein, we discuss a recently developed approach to facilitate the C–C coupling step via the rational tuning of the local microenvironment around active sites. First, recent progress and the mechanism of the CO2RR are briefly described. Next, representative approaches of catalyst engineering, including tandem catalysis, molecular modification, micro-structure regulation, proton donation, hydrophobicity and electric field effect, are highlighted to enrich or regulate the intermediates. Finally, persistent technological challenges are summarized and several personal perspectives are provided to propel the industrial application of the CO2RR. [ABSTRACT FROM AUTHOR]

The central core in non‐fullerene acceptors (NFAs) plays a crucial role in determining the efficiency of organic photovoltaic (OPV) cells. To further advance the development of OPV cells, it is crucial to synthesize novel central cores for constructing high‐performance NFAs. Here, dibenzothiadiazolopyrrolothiophene (DBTPT) is introduced, a ladder‐type [1,2,5]thiadiazolo[3,4‐e]indole‐fused pentacyclic thiophene unit, into photovoltaic materials. By employing the DBTPT unit as the rigid molecular backbone and modifying the side chain of the thiophene π‐bridge, two new acceptor‐π‐acceptor'‐donor‐acceptor'‐π‐acceptor (A‐π‐A'DA'‐π‐A)‐type acceptors (T6 and T9) are synthesized. The effects of lateral alkyl and alkoxy side chains on the optoelectronic properties, charge transport, and molecular packing order are systematically investigated. When blended with polymer donor Poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b']dithiophene))‐alt‐(5,5‐(1',3'‐di‐2‐thienyl‐5'7'‐bis(2‐ethylhexyl)benzo[1',2'‐c:4',5'‐c']dithiophene‐4,8‐dione))] (PBDB‐T), the blend film based on T9 with alkoxy side chains shows favorable molecular stacking and phase separation, resulting in excellent charge transfer performance. Benefiting low energetic disorder, PBDB‐T:T9‐based cell achieves an efficiency of 12.6% with a markedly low energy loss of 0.568 eV. The preliminary results demonstrate that the DBTPT unit has great potential for the construction of novel NFAs for high‐performance OPV cells. [ABSTRACT FROM AUTHOR]

The role of pumped storage in global energy structure transformation is becoming increasingly prominent. This article introduces a flexible excitation system based on fully controlled device converters into pumped storage units (PSUs). It can address the issues of insufficient excitation capacity and limited stability associated with traditional thyristor excitation systems. The study focuses on linear active disturbance rejection control (LADRC) for the flexible excitation control system of pumped storage units and utilizes intelligent optimization algorithms to optimize the controller parameters. This addresses the inherent problem of traditional PID controllers, which are unable to alleviate the trade-off between response speed and overshoot. At the same time, the robustness and anti-interference of the control system are improved, effectively enhancing the performance of the pumped storage flexible excitation control system. Simulation verifies the feasibility and superiority of the proposed method. [ABSTRACT FROM AUTHOR]