变频调速技术在局部通风机中的应用

变频调速技术,正是顺应了工业生产自动化发展的要求,一改普通电动机只能以额定的转速运行的固定模式,使得电动机及其负载在无须任何改动的情况下即可以按照我矿生产要求调整功率输出,从而降低电机功耗以达到设备高效运行的目的。     

显像管玻壳退火炉热平衡测试及评估

通过对4台玻壳退火炉的热平衡测试、计算及分析,得到了玻壳退火炉热平衡收支数据,计算出玻璃成品的单位质量产品耗热量、单位质量产品燃气耗量等主要技术经济指标。提出了进一步提高热效率的技术措施。     

NIR-Triggered Generation of Reactive Oxygen Species and Photodynamic Therapy Based on Mesoporous Silica-Coated LiYF4 Upconverting Nanoparticles

To date, the increase in reactive oxygen species (ROS) production for effectual photodynamic therapy (PDT) treatment still remains challenging. In this study, a facile and effective approach is utilized to coat mesoporous silica (mSiO₂) shell on the ligand-free upconversion nanoparticles (UCNPs) based on the LiYF₄ host material. Two kinds of mesoporous silica-coated UCNPs (UCNP@mSiO₂) that display green emission (doped with Ho³⁺) and red emission (doped with Er³⁺), respectively, were successfully synthesized and well characterized. Three photosensitizers (PSs), merocyanine 540 (MC 540), rose bengal (RB), and chlorin e6 (Ce6), with the function of absorption of green or red emission, were selected and loaded into the mSiO₂ shell of both UCNP@mSiO₂ nanomaterials. A comprehensive study for the three UCNP@mSiO₂/PS donor/acceptor pairs was performed to investigate the efficacy of fluorescence resonance energy transfer (FRET), ROS generation, and in vitro PDT using a MCF-7 cell line. ROS generation detection showed that as compared to the oleate-capped and ligand-free UCNP/PS pairs, the UCNP@mSiO₂/PS nanocarrier system demonstrated more pronounced ROS generation due to the UCNP@mSiO₂ nanoparticles in close vicinity to PS molecules and a higher loading capacity of the photosensitizer. As a result, the three LiYF₄ UCNP@mSiO₂/PS nanoplatforms displayed more prominent therapeutic efficacies in PDT by using in vitro cytotoxicity tests.     

Key Residues Affecting Binding Affinity of Sirex noctilio Fabricius Odorant-Binding Protein (SnocOBP9) to Aggregation Pheromone

Sirex noctilio Fabricius (Hymenoptera Siricidae) is a major quarantine pest responsible for substantial economic losses in the pine industry. To achieve better pest control, (Z)-3-decen-ol was identified as the male pheromone and used as a field chemical trapping agent. However, the interactions between odorant-binding proteins (OBPs) and pheromones are poorly described. In this study, SnocOBP9 had a higher binding affinity with Z3D (Ki = 1.53 ± 0.09 μM) than other chemical ligands. Molecular dynamics simulation and binding mode analysis revealed that several nonpolar residues were the main drivers for hydrophobic interactions between SnocOBP9 and Z3D. Additionally, computational alanine scanning results indicated that five amino acids (MET54, PHE57, PHE71, PHE74, LEU116) in SnocOBP9 could potentially alter the binding affinity to Z3D. Finally, we used single-site-directed mutagenesis to substitute these five residues with alanine. These results imply that the five residues play crucial roles in the SnocOBP9-Z3D complex. Our research confirmed the function of SnocOBP9, uncovered the key residues involved in SnocOBP9-Z3D interactions, and provides an inspiration to improve the effects of pheromone agent traps.     

农电实现降损增效的途径讨论

线损率和抄核收到位率是农电管理的重要经济技术指标,也是农电生产经营管理水平和实现经济效益的综合反映。多管齐下,加强用电管理,降低线损率,确保抄核收工作到位是实现农电降损增效的有效途径。     

填充球蓄热室热效率影响因素数值分析

利用自行设计的填充球蓄热室蓄热放热过程模拟系统,从蓄热室几何参数,相变球性能参数和外界操作参数三个方面分析了各因素对热效率的影响,得出一定的规律,对工程设计具有一定的指导作用.     

The Pay As You Save program in rural Arkansas: An opportunity for rural distribution cooperative profits

This case study highlights the success of the Ouachita Electric Cooperative’s Pay As You Save program in Camden, Ark., in bringing both electricity bill savings to customers and benefits to implementing utilities, especially in rural areas. It is not specifically a low-income energy assistance program, but does benefit customers with high energy burdens. Through its on-bill tariff design, PAYS overcomes many barriers, such as the split incentive challenge and the need for upfront outlays.     

有源介观RLC电路的量子波函数及其双波描述

用表象变换的方法求得了介观RLC电路的量子波函数，并由此求得了电荷和电流的量子涨落，同时又用双波函数方法研究了有源介观电路的量子效应。通过两种方法的比较可知，电路的量子涨落与所处的状态密切相关，这一点由双波函数方法清楚可见。用双波函数求得的电荷和电流的系综平均值正是用波函数求得的电荷和电流的期望值。     

Function of Graphene Oxide as the “Nanoquencher” for Hg2+ Detection Using an Exonuclease I-Assisted Biosensor

Graphene oxide is well known for its excellent fluorescence quenching ability. In this study, positively charged graphene oxide (pGO25000) was developed as a fluorescence quencher that is water-soluble and synthesized by grafting polyetherimide onto graphene oxide nanosheets by a carbodiimide reaction. Compared to graphene oxide, the fluorescence quenching ability of pGO25000 is significantly improved by the increase in the affinity between pGO25000 and the DNA strand, which is introduced by the additional electrostatic interaction. The FAM-labeled single-stranded DNA probe can be almost completely quenched at concentrations of pGO25000 as low as 0.1 μg/mL. A simple and novel FAM-labeled single-stranded DNA sensor was designed for Hg²⁺ detection to take advantage of exonuclease I-triggered single-stranded DNA hydrolysis, and pGO25000 acted as a fluorescence quencher. The FAM-labeled single-stranded DNA probe is present as a hairpin structure by the formation of T–Hg²⁺–T when Hg²⁺ is present, and no fluorescence is observed. It is digested by exonuclease I without Hg²⁺, and fluorescence is recovered. The fluorescence intensity of the proposed biosensor was positively correlated with the Hg²⁺ concentration in the range of 0–250 nM (R² = 0.9955), with a seasonable limit of detection (3σ) cal. 3.93 nM. It was successfully applied to real samples of pond water for Hg²⁺ detection, obtaining a recovery rate from 99.6% to 101.1%.