煤矿采掘工程平面图动态管理CAD系统研究

针对我国煤矿生产管理现状,研究了采掘设计、采掘计划和采掘测量管理等问题,建立了相应的管理系统数学模型,开发了煤矿采掘工程平面图动态管理系统。该系统可解决采掘数据、采掘图形以及两者之间的动态管理问题,使采掘设计、采掘计划和采掘测量的管理融为一体,实现煤矿采掘生产动态管理。实际应用证明,该系统使用效果良好。     

低度白酒除浊研究进展

低度白酒是 2 1世纪白酒消费的主流。首先对低度白酒中沉淀性物质的形成机理作了简要概述 ,并着重介绍了低度白酒除浊方法的研究进展。低度白酒除浊技术在除去沉淀性物质方面的研究成果较多 ,但提高沉淀性物质在低度白酒中溶解度方面的研究前景诱人。     

如何正确使用Betacam SP上的MiXing功能键

在我们的日常工作中，每天滚动播出的每一条新闻片子都要在配音间由录音师进行配音及合成，然后经过有关领导审查，通过了才可送到播出线。但是常常会遇到这种情况：新闻片子在配音间配音完毕后，经领导审查，认为有些画面需要进行修改，编辑记者就会到自编间调整画面，然后再送到审看间，重新请领导再次审查。领导审查时，画面内容虽说通过了，但有时又出现了声音上的问题，表现为背景声过大，甚至压过了解说的音量，使人无法听清解说词的内容，造成解说与效果声互相干扰，更为严重的是有些新闻片子在修改后没有时问重审，而是直接送到了播出线播出，结果造成了播出事故，为什么会出现这种情况？原因是什么呢？     

Two Cd(II) coordination polymers based on asymmetrical Schiff-base ligand with five- and six-membered N-containing heterocyclic rings: Synthesis,crystal structures and luminescent properties

Two cadmium inorganic–organic hybrid coordination polymers [CdL(SCN)₂]_n (1) and [CdLI₂]_n (2), have been synthesized and characterized by IR spectroscopy, elemental analysis, XRPD, thermogravimetric (TG) analyses and X-ray crystallography, where L is 4-(pyridine-4-yl)methyleneamino-1,2,4-triazole. Asymmetrical Schiff-base ligand L acts as a bidentate bridging ligand to bind two Cd(II) centers through two terminal N_triazolyl and N_pyridyl donors in polymers 1 and 2. Polymer 1 displays a new 3D inorganic–organic hybrid network generated through the coordination interactions between Cd-(1,3-μ-SCN⁻) 2D inorganic sheets and bidentate bridging ligands. The structure of polymer 2 is a 3D chiral supramolecular framework which contains helical chains on 2₁ axis. Each Cd(II) center is coordinated by two ligands and two I⁻ donors to attain a distorted tetrahedral environment. The luminescent properties of polymers 1 and 2 were investigated in the solid state at room temperature.     

Experimental investigation on color variation mechanisms of structural light in Papilio maackii ménétriès butterfly wings

The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch quarries or display themselves beauty, in-vestigation on mechanisms of structural light is an important aspect of bionics. Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing sur-face and soon returning back to the original color, the relationship between micro-structure, optics characteristic of scales and changing color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Ultraviolet (UV)-Visible Spectropho-tometer. The color variation mechanisms of blue scales of Papilio maackii mé-nétriès in Chinese Northeast were revealed in this paper. When visible lights trav-eled through the concaver structure with multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths pro-duced interference and color at that wavelength came into being. It has important academic reference value to biomimetics design of video stealth materials.     

高炉上料小车控制系统的应用

本文通过分析炼钢高炉上料小车系统对控制技术的需求,介绍了在自动控制中采用变频器实现调速的方法,并探讨了变频器的抱闸控制逻辑和时序,通过S7-300 PLC控制系统给出控制信号,完成整个系统的自动控制,达到生产工艺的要求。经试验证明:该控制系统具有效率高、能耗低、故障率低等优点,具有较好的实用性能和市场价值。     

调音台的发展历程

从索尼的John East调音台到Antony David调音台,近60年来有关调音台的生产和技术进步,记录了调音台发展的历程。     

Effect of Different Solvents on the Measurement of Phenolics and the Antioxidant Activity of Mulberry (Morus atropurpurea Roxb.) with Accelerated Solvent Extraction

The effects of 9 different solvents on the measurement of the total phenolics and antioxidant activities of mulberry fruits were studied using accelerated solvent extraction (ASE). Sixteen to 22 types of phenolics (flavonols, flavan‐3‐ols, flavanol, hydroxycinnamic acids, hydroxybenzoic acids, and stilbenes) from different mulberry extracts were characterized and quantified using HPLC‐MS/MS. The principal component analysis (PCA) was used to determine the suitable solvents to distinguish between different classes of phenolics. Additionally, the phenolic extraction abilities of ASE and ultrasound‐assisted extraction (UAE) were compared. The highest extraction efficiency could be achieved by using 50% acidified methanol (50MA) as ASE solvents with 15.14 mg/gallic acid equivalents g dry weight of mulberry fruit. The PCA results revealed that the 50MA followed by 50% acidified acetone (50AA) was the most efficient solvent for the extraction of phenolics, particularly flavonols (627.12 and 510.31 μg/g dry weight, respectively), while water (W) was not beneficial to the extraction of all categories of phenolics. Besides, the results of 3 antioxidant capability assays (DPPH, ABTS free radical‐scavenging assay, and ferric‐reducing antioxidant power assay) showed that water‐based organic solvents increased the antioxidant capabilities of the extracts compared with water or pure organic solvents. ASE was more suitable for the extraction of phenolics than UAE.     

Bi系高Tc氧化物超导体的制备

对Bi系氧化物超导体组份和热处理条件进行了研究。名义组份原子比Bi:Sr:Ca:CU=1:1:1:3时,容易形成高T_c相,偏离这个比例时,则形成多相超导体。烧结温度以865—880℃为最佳。冷却方式和烧结时间对高T_c超导相的形成有明显影响。