Opportunities for plant-derived enhancers for iron,zinc, and calcium bioavailability: A review

Understanding of the mechanism of interactions between dietary elements, their salts, and complexing/binding ligands is vital to manage both deficiency and toxicity associated with essential element bioavailability. Numerous mineral ligands are found in both animal and plant foods and are known to exert bioactivity via element chelation resulting in modulation of antioxidant capacity or micobiome metabolism among other physiological outcomes. However, little is explored in the context of dietary mineral ligands and element bioavailability enhancement, particularly with respect to ligands from plant-derived food sources. This review highlights a novel perspective to consider various plant macro/micronutrients as prospective bioavailability enhancing ligands of three essential elements (Fe, Zn, and Ca). We also delineate the molecular mechanisms of the ligand-binding interactions underlying mineral bioaccessibility at the luminal level. We conclude that despite current understandings of some of the structure–activity relationships associated with strong mineral–ligand binding, the physiological links between ligands as element carriers and uptake at targeted sites throughout the gastrointestinal (GI) tract still require more research. The binding behavior of potential ligands in the human diet should be further elucidated and validated using pharmacokinetic approaches and GI models.     

基于磁开关技术的静电除尘脉冲电源

为提高静电除尘器的工作效率得到陡化的脉冲,提出基于磁开关技术的脉冲供电方式。在分析了多级磁脉冲压缩网络的工作原理及给出磁开关的参数选择基础上,通过PSPICE实现了对二级磁脉冲压缩电路的仿真,仿真结果表明,磁开关可有效陡化高压高频脉冲。     

脉冲电镀Ni—W钻头电参数优选

论述了脉冲电参数的理论选择原则；探讨了脉冲电参数对Ni—W镀层性能的影响规律；介绍了脉冲电镀钻头的室内使用情况。     

脉冲射流驱散上隅角积聚瓦斯的理论实验研究

针对“U”采煤工作面上隅角瓦斯积聚,提出了脉冲射流驱散上隅角积聚瓦斯的新理论和新技术。根据相似理论,建立脉冲射流驱散上隅角积聚瓦斯的实验系统,通过实验验证了其科学性、有效性和可行性。实验结果表明：当脉冲射流风机的旋转方向与主风流方向相同时,允散上隅角积聚瓦斯的效果较好,提高脉冲射流的风速和降低旋转的频率可显著地提高驱散上隅角积聚瓦斯的效果。当射流风速为3－5m/s时,可提高风流的扩散系数2－4倍,有效射程可达10m以上,有效地驱散了工作面上隅角的积聚瓦斯。     

KGT可控硅调速在矿用蓄电池机车上的应用

介绍了直流电动机的调速原理,直流斩波器调压原理,KGT可控硅调速电路简介及工作原理。KGT应用在电机车上起动平稳,调速均匀,节约电能,延长蓄电池的使用寿命。     

磨料水射流切割机的数控系统

本文介绍了ＳＭＤ－１型两坐标数控磨料水射流切割机控制系统的软件设计及硬件配置。使用结果表明该数控系统具有简单、可靠、易操作、抗干扰性强等优点。不仅适用于磨料水射流切割机，也可用于其它类似加工设备的控制。     

Influence of HVOF coating on the HCF of 300M low alloy steel

The ultimate methods for solving the contamination of Cr6+ is to replace the Cr electroplating with other techniques, thermal spray provides one of the best choices among those alternative techniques. The influence of coatings upon the fatigue performance of substrate, however,should be labeled as an important factor at some high level applications. The effects of both coatings manufactured by HVOF and Cr electroplating respectively on the fatigue performance of substrate are investigated in this article. These results show that the fatigue limit strength at P= 50 ,of thermal spray coating is 750 MPa in comparing with fatigue limit 726 MPa for substrate, and the fatigue life increase 25,- 150, when comparing with fatigue life of substrate at different stress levels. The fatigue life increases in the stress scope of 750-850 MPa even the area of thermal spray coating is subtracted. Cr eleetroplating coating reduces the fatigue life by 70,- 95, and the fatigue limit is only 600 MPa. Fracture analysis reveals that the main fracture is initiated at the subsurface, which is 0.2-0.5 mm away from substrate surface. The analysis also observes that the crack in the Cr electroplating propagates through the interface and finally into the substrate which hastens the formation of crack origin and the extension of crack in the substrate, however, the crack in the thermal spray coating deflects at the interface, spreads along the interface, as a result,the crack forming in the coatings has no negative influence on the main crack initiator and crack extension in the substrate.     

超宽带无线接入系统在矿井通讯中应用的研究

本文介绍一种超宽带无线接入技术的特点和接收、发射部分的基本结构。通过对矿井下的具体环境和UWB无线接入系统在井下应用存在问题的分析,证明该技术在煤矿井下应用的实际可行性。     

电镀工艺条件与高饱和磁感应CONiFe软磁薄膜的性能

研究电沉积钴镍铁合金工艺条件如电流密度、pH和温度以及镀层厚度对膜层性能的影响。用振动样品磁强计测试膜层的矫顽力Hc、磁化强度Ms及磁滞回线,用高频电感法测试膜层的磁导率μi,用四探针法测试膜层的电阻率ρ。结果表明,膜层的电磁性能与镀覆工艺条件相关,在最佳镀覆工艺条件下(电流密度10mA/cm2,pH=2.8,施镀温度25℃,时间10min)所得合金镀层光亮、致密,有较好电磁特性,Bs达1.9T,矫顽力Hc为1.15Oe,电阻率为45μΩ.cm,在1MHz下磁导率μi为602。     

超声波协同脉冲电解复合研磨加工机理探讨

为了能在满足加工精度要求的同时,提高加工速度,提出了采用超声波协同脉冲电解复合研磨加工技术,探讨了超声波协同脉冲电解复合研磨加工机理,并阐述了脉冲电解加工(PECM)微量腐蚀原理。