Zhejiang Sealand Technology Co., Ltd.is a trustworthy supplier of Oil Mass Flow Meter, Oil Mass Flowmeter, Oil Coriolis Flow Meter, Oil Coriolis Flowmeter, Oil Coriolis Flow Meter, ATEX, IECEx & CE approved.
Operating Environment
Atmospheric pressure: 85kPa~106kPa
Ambient temp.: Refer to Chapter 1.6
Relative humidity: 5%~95%, non condensing
Operating conditions
Fluid: Liquid/Gas
Nominal pressure: 4MPa or 25MPa (Customizable)
Supply voltage: AC 85~265VAC, 50/60Hz or DC 12~24VDC(±5%), 5W
Outputs: Pulse 0~10KHz, RS-485, 4-20mA & HART (optional)
The meter consists of mass flow sensor and transmitter. Mass flow sensor is a phase-sensitive resonant sensor based on Coriolis effect, composed
of vibration tube, signal detector, concussion driver, structural support, shell, etc.
Mass flow transmitter is a micro-programming-centered electronic system, which supplies
thrust to sensor, transforms sensor signal into mass flow signal & others, and improves
accuracy in accordance with temperature parameter.
Oil Mass Flow Meter, Oil Mass Flowmeter, Oil Coriolis Flow Meter, Oil Coriolis Flowmeter, Oil Coriolis Flow Meter Zhejiang Sealand Technology Co., Ltd. , https://www.sealandflowmeter.com
Fluid temperature: -200°C~+200°C (higher temp. model is customizable)
It`s composed of switching power supplier, guard grating, core processor board, display
module, etc., installed in a ex-proof junction box. Switching power supply offers power for
transmitter; safe grating isolates sensor and transmitter intrinsically; core processor detects
& processes sensor phase signal, sends mass flow signal and process communication.
Introduction to High Performance Liquid Chromatography
High-performance liquid chromatography (HPLC) is a powerful analytical technique used for separating, identifying, and quantifying compounds in a mixture. Its fundamental principles are similar to those of classical liquid and gas chromatography, allowing the use of plate theory and kinetic theory to optimize separation efficiency. This makes HPLC a highly effective method for analyzing complex samples with high resolution and sensitivity.
1. **Components of an HPLC System**
A typical HPLC system consists of three main parts: the pump, the chromatographic column, and the detection system. The pump delivers the mobile phase at high pressure, ensuring consistent flow and minimizing pulsation. A high-pressure pump must meet several key requirements: it should maintain a constant flow rate, be resistant to solvent corrosion, operate at high pressures (typically 15–300 bar, with some systems reaching up to 800 bar), and have minimal dead volume to reduce band broadening.
For gradient elution, two high-pressure pumps are often used—one to deliver a strong solvent and the other a weak solvent. These pumps are controlled by a computer, allowing precise control over the composition of the mobile phase, which enhances separation efficiency and resolution.
Sample injection can be done manually using a micro-syringe or automatically via a six-way valve. Detection is commonly performed using UV-Vis absorbance detectors, which offer high sensitivity down to the nanogram level. Other detection methods include fluorescence, refractive index, electrochemical, and mass spectrometry detectors, depending on the nature of the sample.
2. **Types and Applications of HPLC**
**(1) Liquid-Solid Adsorption Chromatography**
In this method, the stationary phase is a solid adsorbent such as silica gel, alumina, or polyamide. The mobile phase is divided into a "primer" and an "eluent." The primer controls the baseline separation, while the eluent adjusts the retention time and provides selectivity for specific components. Common primers include non-polar solvents like hexane or cyclohexane, while eluents may consist of polar solvents such as ethers, esters, or alcohols. This technique is ideal for separating isomers, antioxidants, and vitamins.
**(2) Liquid-Liquid Partition Chromatography**
This type of chromatography uses a liquid stationary phase, typically bonded to a solid support like silica. It includes normal-phase and reverse-phase chromatography. In normal-phase, the stationary phase is polar, and the mobile phase is non-polar, making it suitable for separating polar compounds. Reverse-phase, on the other hand, uses a non-polar stationary phase (e.g., C18) and a polar mobile phase (e.g., water/methanol mixtures), which is ideal for small molecules like peptides, nucleotides, and amino acid derivatives.
Ion pair chromatography is another variant that involves the formation of neutral ion pairs between the analyte and a counterion in the mobile phase. This method is particularly useful for separating charged species, especially in aqueous environments.
**(3) Ion Exchange Chromatography**
This technique relies on the exchange of ions between the sample and the stationary phase, which is typically a resin with fixed ionic groups. It is widely used in the analysis of proteins, nucleic acids, and other charged biomolecules. The mobile phase is usually an aqueous solution, and the pH is adjusted near the pKa of the target compound to maximize retention and separation.
Whether you're working in pharmaceuticals, environmental analysis, or biochemical research, HPLC remains one of the most versatile and reliable techniques in modern analytical chemistry. For more information on HPLC instruments and services, visit Shanghai Qite Analytical Instrument Co., Ltd. at http://www.qite.com. Contact us via phone or fax for assistance. For further reading, check out the latest updates at http://news.chinawj.com.cn.