A New Preparation Method for Amorphous Co-B Alloys Nanoparticles

2011 ◽  
Vol 236-238 ◽  
pp. 1717-1720 ◽  
Author(s):  
Guo Qing Zhong ◽  
Qin Zhong ◽  
Hong Liang Zhou ◽  
Yu Qing Jia
Keyword(s):  
Inductively Coupled Plasma ◽  
Large Scale ◽  
Room Temperature ◽  
Preparation Method ◽  
Average Diameter ◽  
Atomic Emission ◽  
Scale Production ◽  
Solid Reaction ◽  
Inductively Coupled ◽  
Amorphous Nanoparticles

The Co–B alloy can be prepared facilely by a solid-solid reaction of CoCl2•6H2O and KBH4 powders at room temperature. Various characterizations, such as the chemical analysis, inductively coupled plasma-atomic emission spectroscopy (ICP), powder X-ray diffraction, electron diffraction and TEM have been performed. The results indicate that the Co-B alloy obtained by the solid-solid reaction is amorphous nanoparticles. The composition of the alloy is Co1.36B. The average diameter of the Co–B alloy nanoparticles is 30nm–50nm. The room temperature solid-solid reaction is mainly a surface reaction. The direct solid solid reaction between the borohydride and some metal-salts is thermodynamically possible. This simple preparation method may also be used for the large-scale production of the amorphous nanoparticles of some metal-boron alloys.

Improvement of Hydrogenation and Dehydrogenation Kinetics on MgH2 by the Catalytic Effect of ZrO2

2011 ◽  
Vol 117-119 ◽  
pp. 1195-1198
Author(s):  
Liang Zeng ◽  
Toru Kimura ◽  
Satoshi Hino ◽  
Hiroki Miyaoka ◽  
Takayuki Ichikawa ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Room Temperature ◽  
Catalytic Effect ◽  
Atomic Emission ◽  
Hydrogen Desorption ◽  
Milling Process ◽  
Spectroscopy Analysis ◽  
Inductively Coupled ◽  
Dehydrogenation Kinetics ◽  
Kinetics Of

Hydrogen desorption temperature of MgH2, which was milled with 20 pieces of ZrO2 balls for 20 h, was decreased to 240 °C, although steel−ball−milled MgH2 required more than 350 °C. Moreover, the completely dehydrogenated product was able to absorb hydrogen of ~3.5 mass% even at room temperature under 1 MPa hydrogen within 5 hours. Inductively coupled plasma−atomic emission spectroscopy analysis revealed zirconium element was doped into MgH2 from the ZrO2 balls during the milling process. Therefore, it was concluded that the presence of ZrO2 improved the kinetics of the hydrogenation and dehydrogenation behaviors of MgH2.

scholarly journals Study on the Mechanism of Efficient Extracellular Expression of Toxic Streptomyces Phospholipase D in Brevibacillus Choshinensis Under Mg2+ Stress

2022 ◽  
Author(s):  
Shaofeng Chen ◽  
Weide xiong ◽  
Xurui Zhao ◽  
Weiyi Luo ◽  
Xuhui Yan ◽  
...  
Keyword(s):  
Cell Growth ◽  
Inductively Coupled Plasma ◽  
Large Scale ◽  
Cell Injury ◽  
Scale Production ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Study Results ◽  
Brevibacillus Choshinensis ◽  
P2 Promoter

Abstract BackgroundPhospholipase D (PLD) has significant advantages in the food and medicine industries due to its unique transphosphatidylation. However, the high heterologous expression of PLD is limited by its cytotoxicity. The present study sought to express the strong extracellular protein of PLD in the non-pathogenic Brevibacillus choshinensis (B. choshinensis).ResultsThe extracellular PLD was effectively expressed by the strong promoter (P2) under Mg2+ stress, with the highest activity of 1.0×104 U·L-1. The inductively coupled plasma–mass spectrometry (ICP-MS) results elucidated that the fast expression of PLD by P2 promoter without Mg2+ stress induced the ionic homeostasis perturbation caused by the highly enhanced Ca2+ influx, leading to cell injury or death. Under Mg2+ stress, Ca2+ influx was significantly inhibited, and the strengths of P2 promoter and HWP gene expression were weakened. The study results revealed that the mechanism of Mg2+ induced cell growth protection and PLD expression might be related to the lowered strength of PLD expression by P2 promoter repression to meet with the secretion efficiency of B. choshinensis, and the redistribution of intracellular ions accompanied by decreased Ca2+ influx.ConclusionsThe PLD production was highly improved under Mg2+ stress. By ICP-MS and qPCR analysis combined with other results, the mechanism of the efficient extracellular PLD expression under Mg2+ stress was demonstrated. The relatively low-speed PLD expression during cell growth alleviated cell growth inhibition and profoundly improved PLD production. These results provided a potential approach for the large-scale production of extracellular PLD and novel insights into PLD function.

Rapid Catalyst Capture Enables Metal-Free Parahydrogen-Based Hyperpolarized Contrast Agents

2018 ◽  
Author(s):  
Danila Barskiy ◽  
Lucia Ke ◽  
Xingyang Li ◽  
Vincent Stevenson ◽  
Nevin Widarman ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Contrast Agents ◽  
Inductively Coupled Plasma ◽  
Organometallic Compounds ◽  
Atomic Emission ◽  
Platinum Group Metals ◽  
Resonance Spectroscopy ◽  
Plasma Atomic Emission ◽  
Inductively Coupled

<p>Hyperpolarization techniques based on the use of parahydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of parahydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals and their administration in vivo should be avoided.</p> <p><br></p><p>Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 seconds) Ir-based catalyst capture by metal scavenging agents can produce pure parahydrogen-based hyperpolarized contrast agents as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.</p>

Rapid Catalyst Capture Enables Metal-Free Parahydrogen-Based Hyperpolarized Contrast Agents

2018 ◽  
Author(s):  
Danila Barskiy ◽  
Lucia Ke ◽  
Xingyang Li ◽  
Vincent Stevenson ◽  
Nevin Widarman ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Contrast Agents ◽  
Inductively Coupled Plasma ◽  
Organometallic Compounds ◽  
Atomic Emission ◽  
Platinum Group Metals ◽  
Resonance Spectroscopy ◽  
Plasma Atomic Emission ◽  
Inductively Coupled

<p>Hyperpolarization techniques based on the use of parahydrogen provide orders of magnitude signal enhancement for magnetic resonance spectroscopy and imaging. The main drawback limiting widespread applicability of parahydrogen-based techniques in biomedicine is the presence of organometallic compounds (the polarization transfer catalysts) in solution with hyperpolarized contrast agents. These catalysts are typically complexes of platinum-group metals and their administration in vivo should be avoided.</p> <p><br></p><p>Herein, we show how extraction of a hyperpolarized compound from an organic phase to an aqueous phase combined with a rapid (less than 10 seconds) Ir-based catalyst capture by metal scavenging agents can produce pure parahydrogen-based hyperpolarized contrast agents as demonstrated by high-resolution nuclear magnetic resonance (NMR) spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The presented methodology enables fast and efficient means of producing pure hyperpolarized aqueous solutions for biomedical and other uses.</p>

Silicate analysis of carbonated rocks using ICP-AES with calibration by the concentration ratio

2020 ◽  
Vol 86 (5) ◽  
pp. 16-21
Author(s):  
T. A. Karimova ◽  
G. L. Buchbinder ◽  
S. V. Kachin
Keyword(s):  
Inductively Coupled Plasma ◽  
Concentration Ratio ◽  
Total Error ◽  
Atomic Emission ◽  
Emission Spectrometry ◽  
Calibration Error ◽  
Plasma Atomic Emission Spectrometry ◽  
Standard Samples ◽  
Inductively Coupled ◽  
Carbonate Materials

Calibration by the concentration ratio provides better metrological characteristics compared to other calibration modes when using the inductively coupled plasma atomic emission spectrometry (ICP-AES) for analysis of geological samples and technical materials on their base. The main reasons for the observed improvement are: i) elimination of the calibration error of measuring vessels and the error of weighing samples of the analyzed materials from the total error of the analysis; ii) high intensity of the lines of base element; and iii) higher accuracy of measuring the ratio of intensities compared to that of measuring the absolute intensities. Calcium oxide is better suited as a base when using calibration by the concentration ratio in analysis of carbonate rocks, technical materials, slags containing less than 20% SiO2 and more than 20% CaO. An equation is derived to calculate the content of components determined in carbonate materials when using calibration by the concentration ratio. A method of ICP-AES with calibration by the concentration ratio is developed for determination of CaO (in the range of contents 20 – 100%), SiO2 (2.0 – 35%), Al2O3 (0.1 – 30%), MgO (0.1 – 20%), Fe2O3 (0.5 – 40%), Na2O (0.1 – 15%), K2O (0.1 – 5%), P2O5 (0.001 – 2%), MnO (0.01 – 2%), TiO2 (0.01 – 2.0%) in various carbonate materials. Acid decomposition of the samples in closed vessels heated in a HotBlock 200 system is proposed. Correctness of the procedure is confirmed in analysis of standard samples of rocks. The developed procedure was used during the interlaboratory analysis of the standard sample of slag SH17 produced by ZAO ISO (Yekaterinburg, Russia).

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