整体壁板离散填料滚弯成形有限元模拟

具有一定曲率外形的铝合金整体壁板属于典型的多筋零部件,传统弯曲成形工艺成形困难,容易产生多种缺陷。提出了离散填料辅助滚弯成形整体2A12T4铝合金壁板滚弯工艺,并通过实验与整体填料滚变成形进行了对比,同时采用有限元模拟技术,探究了离散填料辅助整体壁板滚弯成形中的影响因素。研究结果表明:填料数量、上下垫板厚度等因素对成形性能影响较大,填料在3~6块时成形稳定,可以有效地避免筋条屈曲与失稳;随垫板厚度增加,壁板表面圆弧更加光滑、连续,但是回弹性增强;上下垫板分别在10~20 mm厚度时,综合性能较好。通过离散填料辅助滚弯技术可以成形出质量较高的整体壁板。     

Combating Biofilm Associated Infection In Vivo: Integration of Quorum Sensing Inhibition and Photodynamic Treatment based on Multidrug Delivered Hollow Carbon Nitride Sphere

Recently, quorum sensing (QS) inhibitors (QSIs) have been combined with antibiotics to enhance antibiofilm efficacy in vitro and in vivo. However, targeting QS signals alone is not enough to prevent bacterial infections. Drug resistance and recurrence of biofilms makes it difficult to eradicate. Herein, photodynamic therapy (PDT) is selected to unite QSIs and antibiotics. A synergistically antibiofilm system, which combines QSIs, antibiotics, and PDT based on hollow carbon nitride spheres (HCNSs) is envisaged. First, HCNS provides the multidrug delivering ability, enabling QSIs and antibiotics to be released in sequence. Subsequently, multistage releases sensitize bacteria effectively, potentiating the chemotherapeutic effects of the antibiotics. Finally, the integration of QSIs and PDT not only minimizes the possibility of drug resistance, but also overcomes the problem of limited mass and extension of PDT. Even after 48 h of incubation, the bacterial biofilm is obviously inhibited. And its biofilm disperse efficiency exceeds 48% (compared with QSI‐potentiated chemotherapy group) and 40% (compared with PDT group). Besides, the inhibition of the QS system influences phenotypes related to virulence factor production and surface hydrophobicity, which weaken biofilm invasion and formation. Eventually, this system is applied to disperse bacterial biofilm in vivo. Overall, PDT and QS modulation are devoted to eradicate drug resistance and recurrence of the biofilm.     

Specific Oxygenated Groups Enriched Graphene Quantum Dots as Highly Efficient Enzyme Mimics

Significant progress is achieved for the utilization of graphene quantum dots as enzyme mimics in various biomedical fields recently. Although promising, the biocatalytic performance is far from satisfactory. Here, the rational design and synthesis of specific oxygenated groups enriched graphene quantum dots (o‐GQDs) via a facile oxidation reflux route is reported. These well‐prepared o‐GQDs with uniform size exhibit an ultrahigh peroxidase‐like activity in a wide range of pH values, and their superior performance is verified by using glucose detection as a typical model. Compared with classical nanozymes, these o‐GQDs show multiple times higher enzymatic activity. It is believed that the super facile synthesis strategy can greatly facilitate the practical use of o‐GQDs as enzyme mimics in the future.     

第二代高温辊式破碎机用辊轴的研究

根据傅里叶定律、牛顿冷却定律以及辊式破碎机辊轴的有关参数建立了辊轴的热传导模型,模拟计算了不同工况下的辊轴使用情况。在600℃工况温度时,辊轴采用风冷、使用40Cr材料可以安全使用;但在850℃工况温度时,辊轴材料需更换为0Cr18Ni9,或辊轴材料不变,冷却方式改用水冷,方可满足使用安全。     

膜分离淡水用于氰化镀镉漂洗水的可行性研究

考察了漂洗水中游离氰、硫酸钠、碳酸钠、钙离子、镁离子、铁离子等的含量及其pH对镉镀件表面腐蚀的影响。结果发现,漂洗水中游离氰的浓度对镉镀件表面的腐蚀起到决定性的作用,漂洗水中游离氰的质量浓度应控制在40 mg/L以下。将膜分离淡水回用于氰化镀镉后的漂洗时,要有足够的回用量,并且根据镀件的形状进行适当调整。     

Preface to the Special Issue on Si-Based Materials and Devices

It has been well known that the development of microelectronic and integrated circuit (IC), mainly based on silicon materials, have changed the way of our life dramatically and accelerated the development and innovation of new technologies. With the increase of integration density in ICs, the gate lengths of transistors are now scaled down to 7 nm, leading to fundamental challenges to keep up with the Moore’s law. One possible solution is to integrate optical circuits into the Si microelectronic platform to achieve high density electronic–photonic integration. This will combine the advantages of photons in energy-efficient and high bandwidth data transmission with those of electrons in high-speed data processing and high performance logics. It will thereby overcome the interconnect bottleneck and achieve high functionality as an extension to Moore’s law. In this opto– electro integration system, monolithic integrated group IV lasers are of great interest. However, the indirect bandgap nature of crystalline silicon limits its application in optoelectronics. In recent years, many researchers have tried to use the nano-sized Si structure or introduce group IV alloys, such as Ge, GeSn or other compounds, to address the light source issue and establish all Si-based electronic–photonic ICs.     

Growth inhibition of Fusarium graminearum and deoxynivalenol detoxification by lactic acid bacteria and their application in sourdough bread

Eight lactic acid bacteria (LAB) strains were screened for their ability to inhibit Fusarium graminearum (F. graminearum) growth and remove deoxynivalenol (DON). Furthermore, the selected LAB strains were applied as starter cultures to evaluate their performance during the breadmaking process. Lactobacillus plantarum (L. plantarum) AR524 exhibited strong inhibitory activity against F. graminearum growth in a pH-dependent manner and removed up to 40.9% of DON, mainly through cell wall binding. Compared with the control, L. plantarum AR524 inhibited 60.19% of F. graminearum growth and removed 50.53% of DON during breadmaking. The texture properties of the bread were also remarkably improved by L. plantarum AR524, and its shelf life was extended from 3 days to 6 days without the application of any chemical preservatives. Therefore, L. plantarum AR524 shows excellent potential for application as a bioprotective starter culture in bakery products.     

麻地梁煤矿智能化装备应用与生产管理变革的思考

随着互联网技术、5G、智能装备等高新技术的快速发展，以智能感知、智能决策和智能控制为代表的的智能化开采越来越成为煤炭安全高效开采的发展方向。本文首先从检修班、生产班、设备库存、生产管理等方面对传统煤矿装备及生产管理现状进行阐述，分析现有煤矿装备及管理模式存在的问题。然后，以内蒙古智能煤炭有限责任公司麻地梁煤矿智慧矿山智能化工作面建设为工程背景，从智能化装备的组建、功能、库存管理、生产管理、运行优势和成功实践等角度介绍智能化装备的应用与生产管理，构建了以煤矿大数据库为基础的管理体系，提出了 “管设备，就是管生产、管安全”的新的管理理念。该体系的建立及理念的提出，可为突破传统生产管理模式、进行新型智能化煤矿建设提供借鉴和参考。     

某无链供弹装置的仿真与试验

为了提高供弹装置各运动构件的可靠性,对某无链供弹装置进行建模进行研究。通过ADAMS软件建立无链供弹装置的运动学及动力学方程,以2发弹的仿真曲线为例进行多发炮弹与闭合弹链运动交接的仿真分析,得到弹丸位移、加速度等参数曲线,并通过激光位移传感器进行系统测试。测试结果表明,供弹机构的动态特性明显,对供弹机构可靠性的进一步提高及结构的改进提供了参考。