Capillary micro

Acetic acid and 10, 15, or 20% acetyl chloride were fed as a mixture into a modified falling film micro reactor (also termed micro capillary reactor in [57]) at a massflow rate of 45 g min and a temperature of 180 or 190 °C [57]. Chlorine gas was fed at 5 or 6 bar in co-flow mode so that a residual content of only 0.1% resulted after reaction. The liquid product was separated from gaseous contents in a settler and collected. By exposure to water, acetyl chloride and acetic anhydride were converted to the acid. The hydrogen chloride released was removed. 

To determine organotin compounds in amounts down to 1 - 5 ng/1, McAvoy et al. [ 129] ethylated the seawater, isolated organotin solid-phase micro extraction and determined it by micro capillary GCMS. 

Furthermore, the micro-capillary-shaped sensor has an excellent sensor-surface-area to sample-volume ratio, which enables quick and efficient capture of biomolecules. 

Adapting the evaporative light scattering device (ELSD) to pHPLC was investigated by Gaudin et al. Quantitative analysis by ELSD is often hindered by nonlinearity however, reduction of the flow rate, resulting in better homogeneity of droplet size distribution, has increased the linearity of the response with ELSD. Despite the predictable effect on droplet size in relation to the reduction of the inner diameter of the capillary inside the nebulizer, ELSD is relatively simple to adapt to micro/ capillary EC. ... 

Liquid Chromatograph. The liquid chromatograph was comprised of a Waters 660 Solvent Programmer, two Waters 6000A pumps, a Waters U6-K Injector and a Waters 440 absorbance detector (254 nm). Whatman micro-capillary tubing (0.007" ID) was used to transfer the HPLC column effluent from the 254 nm absorption detector to the fluorescence detector. 

HPLC/OMA System. In this study, the HPLC effluent stream was passed through three flow-cells connected in series with different lengths of Whatman micro-capillary (0.007 " I.D.) tubing. The first flow-cell monitored the absorption at 254 nm and was used to key the recording of absorption and fluorescence spectra of the effluent stream passing through the second and third flow-cells, respectively, at peak maxima. 

CCKCD) in the absence and presence of SDS. The iq>per panel shows die separation of 10 picomoles of the digest on a micro capillary column (360 pm outer, 250 pm inner diameter. 200 mm length) filled with S pm Vydac CIS support The column was prepared as described in Materials and Methods. The separation of the same sample on the same column in the presence of 0.1 % SDS is shown in the lower panel. 

The usefulness of the SDS removal precolumn was demonstrated using an LC-MS system on a micro capillary column with an inner diameter of 250 pm. SDS-removal precolumns can be used on micro capillary columns of larger dimensions as well. Our experience has shown that it is... 

Makihara, M., Sasakura, K. and Nagayama, A., The Flow of Liquids in Micro-Capillary Tubes - Consideration to Application of the Navier-Stokes Equations, Journal of the Japan Society of Precision Engineering, 1993, 59(3), 399-404. 

Hopkins R., Faghri A., Khrustalev D., (1999), Flat miniature heat pipes with micro capillary grooves. Journal of heat transfer, Vol.121,102 - 109... 

Meyer, E., Dasgupta, S., Shaddock, D., Tucker, J. and Pillion, R., 1993, A Silicon-Carbide Micro-Capillary Pumped Eoop for Cooling High Power Devices, 9 Semiconductor Thermal Measurement and Management Symposium, pp. 364-368. 

Before starting extensive experiments, a procedure recommended by Kaiser and Oel-rich (1981) to rule out adsorbents by fast experiments should be employed. Each elution experiment takes about 20 s. For this purpose samples are applied on a 50 X 50 mm TLC plate at 9 points, which are exactly 10 mm apart. Five microlitres of methanol are drawn into a micro-capillary with a Pt-Ir point. By applying the point of the filled capillary on one of the sample points on the plate, methanol is introduced onto the plate. A miniature radial chromatogram of ca. 7 mm diameter is produced. If the sample components remain at the point of application, the use of this adsorbent type is ruled out for HPLC usage. To make sure, the procedure is repeated with 5 pi of acetonitrile and tetrahydrofuran, respectively. If the products still remain at the point of application, the situation will not be changed by using any other mobile phase that is suitable for preparative chromatography work. 

Profile LC Packings is a privately held company based in San Francisco, Amsterdam and Zurich. It was founded in Zurich in 1987 with the goal to develop, manufacture, and commercialize packed microcolumns for use in HPLC. The company offers a complete range of products for use in microseparation techniques such as micro, capillary and nano LC, including electrochromatography, capillary electrophoresis, and LC-MS. 

The driving forces for the rapid development and growth In mlcrobore column HPLC are (1) savings In solvent consumption a total saving of up to 99.9% can be achieved when narrow-bore microparticle packed columns or open—tubular micro-capillary columns are used (2) the high separation power using long column and small particles (e.g., 3 nm) (3) the compatibility of the column eluent flow rates with a mass spectrometer and flame based detectors and (4) opportunities In new detector development,... 

FIG. 1 Schematic cross sections of selected microelectrode configurations, (a) Nomenclature for parts of microelectrode, (b) Na+-sensitive microelectrode (22), (c) recessed-tip Na+-sensitive microelectrode (27), (d) liquid ion-exchanger micropipette electrode (38), (e) coated wire electrode (16), (f) flow-through ISE (e.g., NOVA 6, Boehringer ISE 2020), (g) micro-capillary glass electrode of tubular shape (e.g., Radelkis OP-266), (h) planar sensor fabricated by microelectronic technology (93), (i) ISFET sensor (94). 

In micro-capillary electrodes, the active measuring membrane is the section of the internal wall of a micro-capillary. A few microliters of sample solution... 

Shadpour et al. [81] and Osiri et al. [82] employed SDS micro-capillary gel electrophoresis (SDS p-CGE) and micellar electrokinetic capillary (MEKC) electrophoresis in the first and second dimensions, respectively, to sort intact proteins using a poly (methylmethacrylate), PMMA, microchip. A diagram of the microchip is shown in Fig. 4. The electrophoresis commenced in the first dimension for a prescribed amount of time and, then, the bands from the first dimension were sequentially injected into the second dimension for development. The 2D electrophoresis system could generate a peak capacity of 2,600 for proteins isolated from fetal calf serum (see Fig. 4). 

A significant reduction of the column ID put stringent demands on the instrumentation for micro-LC as all volumetric extra-column dispersion contributions must be down scaled accordingly. Initial developments in this area were achieved on modified standard LC instruments. For approximately 10 years, dedicated instrumentation for micro-, capillary-, and nano-LC has become commercially available and was recently discussed [33]. 

Figure 6 The microslide - a thin, flat rectangular micro-capillary of glass, useful for preparation of liquid samples vulnerable to...

As mentioned above, ESI instruments were coupled to liquid chromatography. The biggest impact in ESI MS has been the adaptation to reduced flow capabilities in the 10-500 nl/min range. Wilm and Mann [115] and Emmett and Caprioli [116] developed such improvements in parallel. The combination of nano-flow LC with micro-capillary reversed phase HPLC and nano-ES has i) dramatically improved the sensitivity of ESI-MS/MS and ii) enabled the automation of protein identification by using an auto sampler for loading of samples onto the LC [117]. 

Kashid, M., Kiwi-Minsker, L. (2011). Quantitative prediction of flow patterns in liquid-liquid flow in micro-capillaries. Chemical Engineering and Processing Process Intensification, 50, 972-978. 

He S, Kohira T, Uehara M, Kitamura T, Nakamura H, Miyazaki M, Maeda H (2005) Effects of interior wall on continuous synthesis of silver nanoparticles in micro-Capillary reactor. Chem Lett 34 748-749 10. Takagi M, Maki T, Miyahara M, Mae K (2004) Production of Titania nanoparticles by using a new microreactor assembled with same axle dual pipe. Chem Eng J 102 269-276... 

Lin CH, Lee GB, Chen SH, Chang GL (2003) Micro capillary electrophraesis chips integrated with buried SU-8/SOG optical waveguides for bio-analytical applicatirais. Sens Actuatraa A 107 125-131... 

Pettigrew K, Kirshberg J, Yerkes K, Trebotich D, Liepmann D (2001) Performance of a MEMS based micro capillary pumped loop for chip-level temperature control. In 14th IEEE international conference on micro electro mechanical systems, Interlaken, Switzerland, pp 427-430, 21-25 Jan 2001... 

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