1975
year, the success of continuous detection of column effluent by a conductivity detector marked the birth of ion chromatography. After nearly three decades of development, ion chromatography (IC) has become a widely used technique for analyzing ionic substances.
Ion chromatography offers fast analysis speed, high sensitivity, and good selectivity, allowing the simultaneous detection of multiple ions. However, it requires careful operation and regular maintenance to avoid failures.
Basic Structure and Principle of Ion Chromatography
The system typically consists of five main components: the pumping system, injection system, separation column, detection system, and suppressor. Each plays a critical role in the overall process:
- Pump: Delivers the mobile phase at a stable flow rate or pressure through the system.
- Injector: Must be resistant to pressure and corrosion, with good repeatability and ease of use.
- Separation Column: Utilizes ion exchange mechanisms, where ions in the mobile phase interact with the resin in the column, leading to separation based on their affinity.
- Detector: Common types include conductivity detectors, UV-Vis detectors, amperometric detectors, and fluorescence detectors.
- Suppressor: Used to reduce background conductivity, improving detection accuracy.
ICS-1000 Dionex Ion Chromatography System
The ICS-1000 system is designed for efficient and accurate ion analysis. It operates in four key parts:
- Elution System: Eluent bottle (1) → eluent valve (2) → pump (3) → pressure sensor (4) → damper (5)
- Injection System: Injection valve (6) → sample loop (7) → heat exchanger (8)
- Separation System: Separation column (9)
- Detection System: Suppressor (10) → conductivity cell (11) → waste line
Failure Analysis and Troubleshooting
Ion chromatography systems are complex, so troubleshooting should start with identifying the symptoms and working step by step to find the root cause.
Pressure Issues
No flow and zero pressure: Could be due to air bubbles in the pump or system leakage. Bleed off the air or check for leaks in tubing and fittings.
High pressure: Usually caused by blockage. Check for clogs in the column inlet, pump valves, or filters.
Fluctuating pressure: May result from empty eluent bottles, dirty check valves, or blocked filter heads. Refill the solvent, clean or replace the check valve, and replace the filter head if necessary.
Peak Anomalies
Poor peak reproducibility: Could be due to column contamination or leaking lines. Clean the column or repair the system.
No peaks observed: Might be due to incorrect analysis time, faulty conductivity cell, or no solution from the pump. Adjust the settings, check the cell, or verify the pump function.
Baseline Issues
Regular baseline jitter: Often caused by air bubbles in the flow path. Purge the system to remove any trapped gas.
Irregular baseline drift: Could indicate a leak in the system or a malfunctioning suppressor. Inspect all connections and refer to the suppressor manual for adjustments.
Tester: Your One-Stop Solution for Testing Industry
Whether you need instrument repair, used equipment, rentals, or consumables, Tester is your go-to platform for all testing-related needs.
- Used Equipment: Chromatography, mass spectrometry, spectroscopy, small instruments, life sciences, and physical testing tools.
- Maintenance: Cross-brand third-party support, machine servicing, training, and certification programs.
- Rental: GC, IC, and more—offers free maintenance, rent-to-buy options, and trade-in deals.
- Consumables: Includes chromatography supplies, lab essentials, spare parts, and auction items.
Visit Tester today to find the right solution for your lab or business.
High resolution
In order to realize a large-area high-resolution Liquid Crystal Display, it is usually necessary to use low-impedance metal materials, high-performance switching elements, and high-precision processing techniques. Aluminum is the most researched and used material for making TFT buses with low-impedance metals. By solving the problems of easy formation of hillocks, chemical corrosion and oxidation of aluminum, alloy methods (such as Al-Cu, Al-Si, Al-Nd and Al-Ti, etc.) and interlayer methods (such as Mo/Al/Mo) have been reported successively. , Cr/Al/Cr and Ti/Al/Ti, etc.), the alloy method is relatively simple in process, but the material has a higher resistivity. In May 1998, IBM developed a 16.3-inch ultra-high resolution (200ppi) a-Si TFT Display using Al-Nd alloy as the gate electrode, and mass production has been achieved. In April 1999, Toshiba introduced the 20.8-inch 16-SVGA (3, 200 × 2, 400) a-Si TFT-LCD, which can be said to represent the highest level of a-Si TFT-LCD in terms of high resolution and high capacity. .
According to Display Search in the third quarter of 2011, the global flat panel display research report "QuarterlyWorldw ide Flat Pane l Dis play Fore cas t Re port" pointed out that the average pixels per inch (ppi) in large-size LCD panels (>9.1 inches) ) Will grow from 88ppi in 2010 to 98ppi in 2015. The ppi of small and medium-sized LCD panels (<9.0 inches) will grow from 180ppi to 300ppi in the same period. With the rise of smart phones, mobile phones will be the most obvious application product for ppi's growth.
Another important way to realize high-resolution liquid crystal display is to develop LT p-Si TFT technology. The resolution of published p-SiTFT-LCD products is generally around 200ppi. Compared with a-Si TFT-LCD, LT p-Si TFT-LCD has a smaller volume of thin film transistors and storage capacitors. Therefore, it has a larger penetration area per inch, resulting in a brighter display. , And save more power. When the market demands higher ppi, low-temperature polysilicon (LTPS) technology becomes the best choice for manufacturing high-resolution thin-film transistor liquid crystal displays.
Contrast
The control ICs, filters and oriented films used in LCD manufacturing are related to the contrast of the panel. For general users, a contrast ratio of 350:1 is sufficient, but such contrast in the professional field does not satisfy users. Demand. Compared with CRT monitors easily reaching 500:1 or even higher contrast, only high-end LCD monitors can achieve this level. The first-tier LCD monitors on the market, such as Samsung, Asus, LG, etc., can reach a contrast ratio of 1000:1. However, because the contrast is difficult to accurately measure with instruments, you have to go and see it yourself when you pick it.
Tip: Contrast is very important. It can be said that the selection of LCD is a more important indicator than bright spots. When you understand that your customers buy LCDs for entertainment and watching DVDs, you can emphasize that contrast is more important than no dead pixels. We When watching streaming media, the brightness of the source is generally not large, but to see the contrast of light and dark in the scene of the character, the texture change from gray to black hair must be shown by the level of contrast. The 256-level grayscale in the test software In the test, more small gray grids can be seen clearly when looking up, which means that the contrast is better!a
Lcd Display Module,Tft Lcd Screen Display,Display Lcd Enclosure,Tft Display Lvds
ESEN HK LIMITED , https://www.esenlcd.com