scholarly journals Hydrochemical Characteristics and Ion Sources of River Water in the Upstream of the Shiyang River, China

2021 ◽  
Author(s):  
ZhiYuan Zhang ◽  
Wenxiong Jia ◽  
Guofeng Zhu ◽  
Yang Shi ◽  
Hui Xiong ◽  
...  
Keyword(s):  
Ion Source ◽  
Ion Sources ◽  
Ion Concentration ◽  
Main Stream ◽  
Weakly Alkaline ◽  
Source Characteristics ◽  
Total Runoff ◽  
Water Chemical Composition ◽  
Inland Rivers ◽  
Autumn And Winter

Abstract As the largest tributary of the Shiyang River, with the average annual inflow of total runoff accounting for 23%, the Xiying River has representative of mountain runoff of inland rivers in the Northwest of China. Using samples collected in this basin from September 2016 to October 2017, the water chemical composition and ion source characteristics of river were studied. The results show that the river is weakly alkaline, the average pH is 8.0 and the TDS is 179.29 mg·L-1. With the elevation decreasing along the river, the TDS of main stream tend to increase firstly and then decrease, but those of TDS of each tributary decrease, and latter is lower than the former. Affected significantly by the flow, the lowest value of ion concentration in river occurs in summer, and the highest occurs in autumn and winter. The hydrochemical type of river is CaMg-HCO3. In the river, the order of cation mass concentration is NH4+<K+<Na+<Mg2+<Ca2+, and that of anion is F-<NO3-<Cl-<SO42-<HCO3-. The sources of ions in river are mainly from the weathering of Silicates and Carbonates. With the elevation decreasing along the river, the influence of Silicates on the inflowing tributaries is gradually strengthened.

scholarly journals Broadband dielectric spectroscopy for monitoring temperature-dependent chloride ion motion in BiOCl plates

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Adrian Radoń ◽  
Dariusz Łukowiec ◽  
Patryk Włodarczyk
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Spectroscopy ◽  
Low Frequency ◽  
Chloride Ion ◽  
Ion Source ◽  
Chloride Ions ◽  
Ion Concentration ◽  
Broadband Dielectric Spectroscopy ◽  
Free Chloride ◽  
Structure Rebuilding

AbstractThe dielectric properties and electrical conduction mechanism of bismuth oxychloride (BiOCl) plates synthesized using chloramine-T as the chloride ion source were investigated. Thermally-activated structure rebuilding was monitored using broadband dielectric spectroscopy, which showed that the onset temperature of this process was 283 K. This rebuilding was related to the introduction of free chloride ions into [Bi2O2]2+ layers and their growth, which increased the intensity of the (101) diffraction peak. The electrical conductivity and dielectric permittivity were related to the movement of chloride ions between plates (in the low-frequency region), the interplanar motion of Cl− ions at higher frequencies, vibrations of these ions, and charge carrier hopping at frequencies above 10 kHz. The influence of the free chloride ion concentration on the electrical conductivity was also described. Structure rebuilding was associated with a lower concentration of free chloride ions, which significantly decreased the conductivity. According to the analysis, the BiOCl plate conductivity was related to the movement of Cl− ions, not electrons.

scholarly journals The Impacts of Groundwater Chemistry on Wetland Vegetation Distribution in the Northern Qinghai–Tibet Plateau

2019 ◽  
Vol 11 (18) ◽  
pp. 5022 ◽  
Author(s):  
Junju Zhou ◽  
Juan Xiang ◽  
Lanying Wang ◽  
Guoshuang Zhong ◽  
Guofeng Zhu ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Groundwater Chemistry ◽  
Ion Concentration ◽  
Tibet Plateau ◽  
Distribution Data ◽  
Vegetation Distribution ◽  
Chemical Parameters ◽  
Weakly Alkaline ◽  
Artemisia Frigida ◽  
The Impact

Groundwater chemistry has an important impact on the vegetation distribution in inland areas. An in-depth understanding of the impact of groundwater chemistry on vegetation can help in developing an effective management strategy to protect the inland ecosystem. The aim of this study was to identify the influence of groundwater chemicals on species diversity and the distribution characteristics of wetland plants at multiple scales based on the groundwater chemical data from 15 sampling points and the distribution data of 13 plants in the Sugan Lake Wetland in 2016. The results show that the groundwater of the Sugan Lake Wetland is weakly alkaline, with high salinity and hardness; the water chemical type is Na-SO4-Cl; the concentration of the major water chemical parameters is significantly different and is the highest in the northwest, followed by the southwest, and is the lowest in the east; with an increase in the groundwater depth, the concentration of major water chemical parameters first showed an increasing trend followed by a decreasing trend; Artemisia frigida Willd, Poa annua L. and Triglochin maritimum L. were adapted to the environment with a higher ion concentration of the groundwater, and their salt resistance was the strongest; Blysmus sinocompressus and Polygonum are more adapted to the environment with lower salinity and hardness of groundwater; Thermopsis lanceolata has stronger adaptability to the ion concentration, salinity, and hardness of groundwater; other plants are adapted to environments where the ion concentration, salinity, and hardness of the groundwater are moderate.

scholarly journals Seasonal variation of the ion upflow in the topside ionosphere during SAPS (subauroral polarization stream) periods

2013 ◽  
Vol 31 (9) ◽  
pp. 1521-1534 ◽  
Author(s):  
H. Wang ◽  
H. Lühr
Keyword(s):  
Frictional Heating ◽  
Ion Source ◽  
Ion Concentration ◽  
Seasonal Effect ◽  
Topside Ionosphere ◽  
Local Formation ◽  
Winter Solstice ◽  
Density Region ◽  
Ion Density ◽  
Important Relationship

Abstract. A statistical study has been performed by using two years of DMSP (Defense Meteorological Satellite Program) plasma observations to investigate the seasonal effect of SAPS (subauroral polarization stream) on the ion upflow in the duskside ionosphere of the Northern Hemisphere. There are obvious upflows occurring in the topside ionosphere around the SAPS region, exceeding 200 m s−1 at winter solstice, indicating an important relationship between SAPS and the local plasma upward motion. Both SAPS and ion upward velocities show similar seasonal variations, largest in winter and smallest in summer, irrespective of geomagnetic activity. A good correlation is found and a linear relationship is derived between SAPS and the ion upflow velocities. During December solstice the average upflow flux can reach about 2 × 108 cm−2 s−1 for more disturbed periods, which is comparable to the typical upflow flux in the dayside cusp region. The depression of the ion temperatures around the peak SAPS region can be understood in terms of the adiabatic cooling. The hot ion cools down when expanding into the low ion concentration region. The electron temperature elevates around the SAPS region because of the reduced Coulomb cooling in the low ion density region. Both the changes of ion and electron temperatures are larger in winter than in summer, however, for Kp < 4 the electron temperatures are almost seasonably independent. The present work highlights the important role of the SAPS-related frictional heating at mid-latitudes on the local formation of the strong upward flow, which might provide a direct ionospheric ion source for the ring current and plasmasphere in the duskside sector.

Ion Sources for Ion Beam Assisted Thin Film Deposmon

1995 ◽  
Vol 396 ◽  
Author(s):  
Igor V. Svadkovsk ◽  
Anatoly P. Dostanko
Keyword(s):  
Ion Beam ◽  
Ion Source ◽  
Ion Sources ◽  
Inert Gases ◽  
Anode Layer ◽  
High Current ◽  
Ion Beam Assisted Deposition ◽  
Ion Energies ◽  
Extended Range ◽  
Basic Distinction

AbstractTwo types of the ion sources for ion beam assisted deposition using inert gases, oxygen or nitrogen are reported. Their design and operational features are presented. Each of them has the properties of two existing main types of the gridless Hall sources: an end-Hall source and the anode-layer version a closed-drift ion source. Basic distinction of the developed sources is the extended range of ion energies in high-current beam for optimization of deposition, cleaning and etching processes.

Gas-discharge ion sources for electromagnetic mass separation on a heavy-ion beam II. operating speed of ion source

1976 ◽  
Vol 41 (5) ◽  
pp. 999-1000
Author(s):  
A. P. Kabachenko ◽  
I. V. Kuznetsov ◽  
Li Hen Su ◽  
N. I. Tarantin
Keyword(s):  
Ion Beam ◽  
Heavy Ion ◽  
Gas Discharge ◽  
Ion Source ◽  
Ion Sources ◽  
Mass Separation ◽  
Operating Speed ◽  
Electromagnetic Mass ◽  
Heavy Ion Beam

scholarly journals A Vacuum Ultraviolet Ion Source (VUV-IS) for Iodide-Chemical Ionization Mass Spectrometry: A Substitute for Radioactive Ion Sources

2020 ◽  
Author(s):  
Yi Ji ◽  
L. Gregory Huey ◽  
David J. Tanner ◽  
Young Ro Lee ◽  
Patrick R. Veres ◽  
...  
Keyword(s):  
Formic Acid ◽  
Methyl Iodide ◽  
Chemical Ionization ◽  
Vacuum Ultraviolet ◽  
Ambient Air ◽  
Radioactive Source ◽  
Ion Source ◽  
Ion Sources ◽  
Ionization Mass ◽  
Molecular Chlorine

Abstract. A new ion source (IS) utilizing vacuum ultraviolet (VUV) light is developed and characterized for use with iodide-chemical ionization mass spectrometers (I−-CIMS). The VUV-IS utilizes a compact krypton lamp that emits light in two wavelength bands corresponding to energies of ~10.0 and 10.6 eV. The VUV light photoionizes either methyl iodide (ionization potential, IP = 9.54 ± 0.02 eV) or benzene (IP = 9.24378 ± 0.00007 eV) to form cations and photoelectrons. The electrons react with methyl iodide to form I− which serves as the reagent ion for the CIMS. The VUV-IS is characterized by measuring the sensitivity of a quadrupole CIMS (Q-CIMS) to formic acid, molecular chlorine, and nitryl chloride under a variety of flow and pressure conditions. The sensitivity of the Q-CIMS, with the VUV-IS, reached up to ~700 Hz pptv−1, with detection limits of less than 1 pptv for a one minute integration period. The reliability of the Q-CIMS with a VUV-IS is demonstrated with data from a month long ground-based field campaign. The VUV-IS is further tested by operation on a high resolution time-of-flight CIMS (TOF-CIMS). Sensitivities greater than 25 Hz pptv−1 were obtained for formic acid and molecular chlorine, which were similar to that obtained with a radioactive source. In addition, the mass spectra from sampling ambient air was cleaner with the VUV-IS on the TOF-CIMS compared to measurements using a radioactive source. These results demonstrate that the VUV lamp is a viable substitute for radioactive ion sources on I−-CIMS systems for most applications. In addition, the VUV-IS can likely be extended to other reagent ions, such as SF6− which are formed from high IP electron attachers, by the use of absorbers such as benzene to serve as a source of photoelectrons.

scholarly journals Challenges and Strategies of Chemical Analysis of Drugs of Abuse and Explosives by Mass Spectrometry

2021 ◽  
Vol 8 ◽  
Author(s):  
Ahsan Habib ◽  
Lei Bi ◽  
Huanhuan Hong ◽  
Luhong Wen
Keyword(s):  
Mass Spectrometry ◽  
Drugs Of Abuse ◽  
Structural Information ◽  
Ambient Ionization ◽  
Ion Source ◽  
Ion Sources ◽  
Mass Spectrometry Analysis ◽  
Ionization Source ◽  
Wide Range ◽  
Challenges And Strategies

In analytical science, mass spectrometry (MS) is known as a “gold analytical tool” because of its unique character of providing the direct molecular structural information of the relevant analyte molecules. Therefore, MS technique has widely been used in all branches of chemistry along with in proteomics, metabolomics, genomics, lipidomics, environmental monitoring etc. Mass spectrometry-based methods are very much needed for fast and reliable detection and quantification of drugs of abuse and explosives in order to provide fingerprint information for criminal investigation as well as for public security and safety at public places, respectively. Most of the compounds exist as their neutral form in nature except proteins, peptides, nucleic acids that are in ionic forms intrinsically. In MS, ion source is the heart of the MS that is used for ionizing the electrically neutral molecules. Performance of MS in terms of sensitivity and selectivity depends mainly on the efficiency of the ionization source. Accordingly, much attention has been paid to develop efficient ion sources for a wide range of compounds. Unfortunately, none of the commercial ion sources can be used for ionization of different types of compounds. Moreover, in MS, analyte molecules must be released into the gaseous phase and then ionize by using a suitable ion source for detection/quantification. Under these circumstances, fabrication of new ambient ion source and ultrasonic cutter blade-based non-thermal and thermal desorption methods have been taken into account. In this paper, challenges and strategies of mass spectrometry analysis of the drugs of abuse and explosives through fabrication of ambient ionization sources and new desorption methods for non-volatile compounds have been described. We will focus the literature progress mostly in the last decade and present our views for the future study.

New Ion Source for High Precision FIB Nanomachining and Circuit Edit

2014 ◽  
Author(s):  
Adam V. Steele ◽  
Brenton Knuffman ◽  
Jabez J. McClelland
Keyword(s):  
Low Temperature ◽  
Failure Analysis ◽  
High Precision ◽  
Spot Size ◽  
Ion Source ◽  
Low Energy ◽  
Energy Spread ◽  
Site Specific ◽  
High Brightness ◽  
Source Characteristics

Abstract We present a review of the Low Temperature Ion Source (LoTIS): its aims, design, performance data collected to date, and focused spot size projections when integrated with a FIB. LoTIS provides a Cs+ beam that has been measured to have high brightness (&gt; 107Am-2sr-1eV-1), and low-energy spread (&lt; 0.5 eV). These source characteristics enable a prediction of subnm focused spot sizes. A FIB with the capabilities enabled by LoTIS would be well-suited to addressing FIB failure analysis tasks such as nanomachining, circuit edit, and site-specific SIMS.

Sign in / Sign up

Export Citation Format

Share Document