ONYX WFX-320 Atomic Absorption Spectrophotometer

SPECIFICATIONS:

Main Specification	Wavelength range	190-900nm
	Wavelength accuracy	±0.5nm
	Resolution	Two spectral lines of Mn at 279.5nm and 279.8nm can be separated with the spectral bandwidth of 0.2nm and valley-peak energy ratio less than 30%.
	Baseline stability	0.005A/30min
	Background correction	The D2 lamp background correction capability at 1A is better than 30 times.
Light Source System	Lamp number	2 lamps (one preheating)
	Lamp current adjustment	Micro-computer control Adjustment range: 0~20mA
	Lamp power supply mode	Powered by square pulses
Optical System	Monochomator	Single beam, Czerny-Turner design grating monochromator
	Grating	1800 l/mm
	Focal length	277mm
	Blazed Wavelength	250nm
	Spectral Bandwidth	0.1nm, 0.2nm, 0.4nm, 1.2nm
Detection and Data Processing System	Detector	Photomultiplier with high sensitivity and wide spectral range.
	Electronic and micro-computer system	Light energy and negative high-voltage auto-balance
	Display mode	LED display of energy and measurement values, concentration direct reading
	Read mode	transient, integral, peak height, peak area. Integral or sampling time is in the range of 0.1-19.9s.
	Scale expansion	0.1~99
	Data processing mode	Automatic calculation of mean, standard deviation and relative standard deviation. Repeating number is in the range of 1-99
	Measurement mode	3~7 standards can be determined for curve fitting. Sensitivity correction available.
	Result printing	Measurement data, working curve, signal profile and analytical conditions can all be printed out.
	Instrument self-check	Check current status of each function key
Flame Analysis	Burner	10cm single slot all-titanium burner
	Spray chamber	All-plastic spray chamber.
	Nebulizer	High efficiency glass nebulizer with metal sleeve.
	Position adjustment	Adjusting mechanism for vertical, horizontal positions and the rotation angle of the burner.
	Gas line protection	Fuel gas leak alarm
Characteristic Concentration and Detection Limit	Air-C2H2 flame	Cu: Characteristic concentration ≤0.025mg/L, Detection limit ≤0.006mg/L;
Function Expansion	Flameless analysis with WF-1C graphite furnace system available.
	Hydride vapor generator can be connected for hydride analysis.
Dimensions and Weight	1020x490x540 mm, 80kg unpacked

ONYX WFX-110/120/130 Spectrophotometer

FEATURES

• High sensitivity, simple and safe operation, low analytical cost, ensured by the patented flame analysis technique (patent No. ZL9210560.7) adopting oxygen-rich air-acetylene flame as the substitution for nitrous oxide-acetylene flame for high temperature element analyses. The flame temperature of the oxygen-rich flame is adjustable continuously between 2300 and 2950℃. (Only for WFX-110)
• Fully automated microcomputer controlled operation
  1. Automatic wavelength peaking for quick and precise operation.
  2. Automatic spectral bandwidth selection.
  3. Automatic hollow cathode lamp changeover.
  4. Automatic instrument parameter setting, including light source power supply, photomultiplier high voltage supply and background correction energy balance.
  5. Automatic signal measurement and data processing. Fast sampling, photo-electric conversion, noise smoothing, integration, curve fitting, background correction and data display can all be done automatically.
• Easy and flexible WINDOWS operating system, with multi-windows processing technology to observe the signal profile, the measured results and the calibration curve at the same time. Various analytical programs, data, signals and graphics can all be stored for later use.
• Fully sealed optical system, keeping the optical elements clean and dry and ensuring long-term high-energy throughput.
• Optimum vibration-absorbing mechanism, ensuring good mechanical stability of the optical system, reducing vibration interference in graphite furnace operation.
• Two background correction systems, deuterium arc background correction system (with high performance deuterium arc lamp) and S-H background correction system (only for WFX-110/120) to realize background correction at all wavelengths.
• Perfect safety protection measures, alarm and automatic safety protection to fuel gas leakage, air pressure deficiency and abnormal flame extinction; spray chamber made of explosion-proof material, all-titanium burner and explosion-proof stopper for flame analyses; alarm and protection function to argon pressure deficiency, insufficient cooling water supply, over-heating and over-current etc. in graphite furnace analyses.
• Multi-analytical functions, providing flame AA, graphite furnace AA, and hydride AA analysis and flame emission analysis.
  

SPECIFICATIONS:

Main Specification	Wavelength range	190 to 900n
	Wavelength accuracy	±0.5nm
	Resolution	better than 0.3nm
	Baseline stability	0.005A/30min
	Background correction	The D2 lamp background correction capability at 1A is better than 30 times. The S-H background correction capability at 1.8A is better than 30 times. (for WFX-120/110)
Hollow Cathode Lamps	Lamp turret	6-lamp turret (WFX-110/120), 4-lamp turret (WFX-130)
	Lamp current adjustment	Automatic adjustment and display. Wide pulse current: 0~25mA, Narrow pulse current: 0~10mA. (WFX-110/120)
	Lamp power supply mode	Powered by two pulses (wide and narrow) simultaneously in WFX-110/120; square-wave pulse in WFX-130.
Optical System	Monochomator	Single beam, Czerny-Turner design grating monochromator
	Grating	1800 l/mm
	Focal length	277mm
	Blazed Wavelength	250nm
	Spectral Bandwidth	0.1nm, 0.2nm, 0.4nm, 1.2nm
Detection and Data Processing System	Detector	Photomultiplier with high sensitivity and wide spectral range.
	Software	Ms-WindowsTM operating system
	Analytical method	Working Curve Method (1st order and 2nd order fitting), Standard Addition Method.
	Repeatable measurement	Maximum 20 times of repeat measurement, automatic calculation of mean value, standard deviation and relative standard deviation.
	Condition reading	With model function
	Result printing	Measurement data and final analytical report printout.
Flame Analysis	Burner	10cm single slot all-titanium burner for Air-C2H2 flame(WFX-110/120/130); 5cm single slot all-titanium burner for oxygen-rich flame (WFX-110).
	Spray chamber	All-plastic spray chamber.
	Nebulizer	High efficiency glass nebulizer with metal sleeve.
	Position adjustment	Adjusting mechanism for vertical, horizontal positions and the rotation angle of the burner.
	Protection for gas system	Fuel gas leak protection, abnormal flame extinction alarm, air-pressure deficiency protection and explosion-proof device.
	Flame ignition	Automatic
Characteristic Concentration and Detection Limit	Normal Air-C2H2 flame	Cu: Characteristic concentration ≤0.05mg/L, Detection limit ≤0.006mg/L;
	Oxygen-rich Air-C2H2 flame (only for WFX-110)	Ba: Characteristic concentration ≤0.22mg/L
	Hydride generation	Hg: detection limit ≤0.5ug/L
Power Supply	220V, 200W
Dimensions	1020X492X537mm
Weight	Unpacked 80kg

Flow Injection Analysis

Flow injection analysis ( FIA ) is an analytical technique that we use to measure the concentration of micro and trace elements in seawater. It yields metal concentrations that compare very well with traditional atomic absorption spectrophotometry (AAS). Its main advantage is that it can be used shipboard to gather near real time information on natural metal distributions or in ecosystem manipulations such as the IronEx experiment. FIA employs the continuous flow of a reagent stream into which a sample is injected and the resulting color (spectrophotometric) or light (chemiluninescence), or fluorescence is measured.

This technique relies on laminar flow within very small (< 1mm) i.d. tubing to prevent dispersion of the sample slug, and on precise control of reaction time since reactions are frequently not allowed to go to completion. We currently employ FIA for the analysis of Iron (Fe), Copper (Cu), Manganese (Mn), Cobalt (Co), and Zinc, and plan to add Aluminum (Al) to this list very soon.

ATOMIC ABSORPTION SPECTROPHOTOMETRY (AAS)

This is a technique for elemental analysis in liquids. Metallic species can be determined in both organic and inorganic samples. It is a sensitive technique that can determine the concentration of most elements at the part - per - million (ppm) level. If lower detection limits are required then a graphite furnace is used as the excitation source (GFAAS), replacing the standard flame. GFAAS is for ultra-trace analysis. It has detection limits that exceed the conventional flame by several orders of magnitude.


Through the use of calibration curves, prepared from suitable standards, a high level of accuracy and precision (±1 to 3 %) is achieved for flame AAS. This allows for compositional as well as trace impurity analysis. Most spectral interferences and matrix effects are overcome by utilizing well characterized conditions and matrix matching of samples and standards. GFAAS has an average accuracy of ±20% (relative) which is suitable for reporting at the ultra-trace impurity level.

When using atomic absorption spectrophotometry (AAS) as an analytical
technique the absorption of light of free atoms is measured. Therefore it is one of
the branches of atomic spectroscopy, together with flame photometry (see
Standardbase techniques: “Flame Photometry” that measures the intensity of
light emitted by free atoms when their electrons return to ground state after the
excitation by light). However - unlike flame photometry - AAS is based on the
“first half” of the excitation process, while atoms absorb light getting their
electrons from the ground state to a higher energy level.