金刚石表面镀覆金属的性能研究

对人造金刚石表面进行盐浴镀Ti和化学镀Ni、Cu处理后 ,用SEM观测镀后金刚石的表面形貌及镀层界面 ,并测试分析了镀后金刚石的抗压强度和抗热蚀能力。结果表明 ,盐浴镀Ti的镀层与金刚石的结合界面比化学镀层更为致密 ;经化学镀后的金刚石抗压强度明显提高 ,镀Ti和镀Ni的金刚石抗热蚀能力较好。     

烧结混合机细颗粒物蒸汽相变凝并及水浴协同治理

分析了蒸汽相变凝并及水浴协同治理技术。A钢铁厂烧结一次混合机采用该技术改造后,工作环境明显改善,车间环境空气颗粒物质量浓度大幅降低,设备各项运行参数良好,排放质量浓度满足钢铁企业超低排放指标限值要求。     

冷扩孔并置入栓钉技术止裂效果研究

采用有限单元法对冷扩孔并置入栓钉处理措施进行数值模拟,并对循环荷载下止裂孔孔边应力、应变状态的分析表明,冷扩孔并置入栓钉降低了应力集中部位的应变幅,从而延长疲劳裂纹在止裂孔边的再生寿命,栓钉直径均会影响钻孔止裂相关技术的止裂效果.     

Cold model experiment on dynamic behavior of dross in hot dip plating bath

The motions of top and bottom dross in a continuous hot dip plating bath were investigated using a transparent cold model vessel with a reduced scale of one-tenth. The flow field in the model bath was classified into three regions as usual; the entry region, the exit region, and the region enclosed with a belt. This belt was used as a model for a strip. Polystyrene particles were used as models both for the top and bottom dross while NaCl aqueous solutions of different densities were used as models for plating melts. The motions of model particles were observed by eye inspection and by using a high-speed video camera. Local particle frequency and particle holdup were measured with a newly developed sensor. Typical streak lines for the top and bottom dross particles were similar to main stream lines in the bath. Both the top and bottom dross particles were rich in the region enclosed with the belt. A lot of top dross particles floated on the bath surface near the side walls, while many bottom dross particles stayed on the bottom wall in the entry region.     

Chemically grown Bi2S3 nanorod films for hydrogen evolution

Bi₂S₃ nanorod films were grown on ITO-coated glass substrates through chemical bath deposition (CBD) and annealing in a sulfur atmosphere. The as-deposited films were amorphous/nanocrystalline, with a particle size of 20 nm and a direct optical band gap of 1.87 eV. Upon annealing at 350 °C, the films exhibited a nanorod morphology with a length of 300 nm. Further increasing the temperature from 400 to 450 °C resulted in an increased diameter of nanorods. The direct optical band gap decreased from 1.68 to 1.47 eV upon increasing the annealing temperature from 350 to 400 °C. Photoelectrochemical (PEC) measurements showed that the nanorod films grown on ITO-coated glass substrates exhibited significantly increased PEC activity owing to their nanorod structures. The Bi₂S₃ nanorod films formed at 400 °C exhibited a maximum photocurrent density of 6.1 mA/cm² at 1 V, which was 2.5 times higher than that of the as-deposited films. The enhancement in the photocurrent density could be due to the effective visible-light absorption of Bi₂S₃ nanorods as a result of the increased crystallinity and decreased band gap. This study demonstrates the synthesis route involving a simple and inexpensive CBD method of Bi₂S₃ nanorod films for the optimized PEC water-splitting applications.     

High-performance vertically aligned Bi2O3 nanosheet arrays for water splitting applications by controlling the chemical bath deposition method parameters (precursor concentration and pH)

In this work, vertically aligned β-Bi₂O₃ nanosheet arrays are deposited on FTO using a simple, cost-effective, low-temperature, and easy-tunable technique called chemical bath deposition. Coatings were deposited through selective correlation of varying bismuth ion concentrations at fixed pH and, also, a fixed bismuth ion concentration at different pH values to optimize their structure, morphology, and optical properties. With an increase in bismuth precursor concentration from 0.008 M to 0.5 M, a more crystallized and compact coating with finer nanosheets was formed. Low pH values tended to result in either no coating or a coating composed of discrete particles. As the pH increased to the optimal level, a thicker and more compact coating with a morphology made of thicker and wider nanosheets was formed. Further increase in pH led to a non-uniform coating composed of small and large nanosheets that could not cover the entire surface of the substrate. The optimized photoelectrode exhibited a maximum photocurrent density of 470 μA/cm² at 1.23 V_RHE under 100 mW/cm² simulated sunlight, which is among the top recorded values of Bi₂O₃ photoelectrodes.     

Nanonecklace of CdO through simple solution chemistry

CdO nanonecklace like structure with interconnected nanobeads were produced by air annealed Cd(OH)₂ nanowire structure thin film at 290 °C. Simple and low cost chemical route has been successfully employed for the synthesis of Cd(OH)₂ nanowires on fluorine doped tin oxide (FTO) coated glass substrates at room temperature (27 °C). Structural analysis confirmed the conversion of hydroxide phase to the oxide phase by annealing which also leads to change in optical band gap from 3.5 to 2.34 eV. The necklace like nanostructure represent unique surface morphology which can be emerged as a potential candidate towards wide range of applications in different fields of nanotechnology such as solar cell, gas sensor, supercapacitor and photo-catalyst.     

现代镀覆技术 第二部分──化学镀镍(续4)

给出了各种实用的化学镀镍配方及其工艺条件。     

Heuristic approach for solving employee bus routes in a large-scale industrial factory

This paper compares different methods for solving a location-routing problem (LRP), using real-world data from the bus transport service for employees of a large-scale industrial factory in Thailand. We tested four AI (artificial intelligence) techniques Maximin, K-means, Fuzzy C-means, and Competitive Learning and two hybrids of these four K-means with Competitive Learning and K-means with Maximin to allocate the bus stops. The efficiency of the algorithms was compared, in terms of the quality of the solutions. The K-means with Maximin provided the best solution, as it minimized number of bus stop locations and employees’ total traveling distance while satisfied employee at maximum radius 1.73 km, compared to K-means with Competitive Learning, as the same number of bus stop it provided higher total traveling distance and maximum radius. The other non-hybrid techniques provided higher number of bus stop locations.We then used ant colony optimization (ACO) to determine the optimal routing between the 300–700 bus stops as allocated by K-means with Maximin. The optimal bus routing to transport the factory’s 5000 plus employees required 134 buses (134 independent routes) covering 500 bus stops and traveling nearly 5000 km. While optimal, this routing was costly and created monitoring difficulties. To address these concerns, we constrained the number of bus routes; while this dramatically increased the total distance, it provided a more practical solution for the factory.     

某转管自动机停射故障分析

根据某自动机工作原理和试验情况,分析故障现象,建立了各故障现象间的关系框图,通过详细推理分析和验证,还原故障发生过程。经多方排查验证,最终确定故障原因为左供弹接口和进弹机交接处有负间隙现象,高速进弹时碰撞炮弹药筒口部使外形异常,推弹时受阻,引起后续相关零部件工作异常,进而造成连锁式损坏和最终停射故障。经分析和多次模拟试验,改进优化供、进弹交接处间隙,通过多门炮射击试验验证,再未出现类似停射故障。