Lei Zhou’s Blog

Commercial

CHEMCATS

CHEMCATS (Chemical Catalogs Online) is produced by Chemicals Abstract Service (CAS) and can be searched through the SciFinder, SciFinder Scholar, STN (STN Express, command-line driven STN Messenger language), STN on the Web, and STN Easy interfaces.

Available Chemicals Directory

The Available Chemicals Directory may be called “the mother of all catalog databases”,It is now produced by MDL, and offered in the well-established client-server database systems ISIS, ISENTRIS, and recently also under the new Web interface DiscoveryGate.

ChemACX

The Available Chemical Exchange database was created in 1998 by CambridgeSoft as a Webbased application. In an interesting licence model, ChemACX is also part of the ChemOffice Ultra software package on DVD for use with the desktop ChemFinder application provided by CambridgeSoft.

Chem Sources

Chem Sources is possible via a guest account, but supplier information is only provided for subscribers.

Chemicals Available for Purchase (CAP)

“Searching through suppliers’ catalogs is inconvenient and error-prone - especially if some are paper-based, some are on CD or on-line, or if some need importing into a database. By consolidating the contents of many suppliers’ catalogs into one database, CAP provides you with a convenient way of accessing commercial supplier information in a consistent and efficient manner. CAP enables you to locate readily available supplies of reagents and compounds from a wide variety of suppliers.”

Free

ChemExper

Of the free chemicals directories available on the WWW, ChemExper was produced by the homonymous company ChemExper and probably comes closest to the purpose and functionality of the major commercial sources.

ChemNet

ChemNet is a buyers and sellers portal for chemical and pharmaceutical products. Founded 1995 in the US, it changed owners a few times and since 2001 belongs to the chinese enterprise Zheijang NetSun Co. Ltd.

ICISsearch

As ChemNet, ICISsearch is a portal for chemical products and companies produced by Reed Business Information, a member of Reed Elsevier. The web pages looks tidy, however, many links (“List My Company”, “Advertising Solutions”, “About Us”, “Contact Us” etc.) were found to be faulty.

Super Natural Database

This database contains 45.917 compounds with 2.665.881 conformers available for purchase

ZINC

“ZINC is a free database of commercially-available compounds for virtual screening. ZINC contains over 4.6 million compounds in ready-to-dock, 3D formats. ZINC is provided by the Shoichet Laboratory in the Department of Pharmaceutical Chemistry at the University of California, San Francisco (UCSF). ”

NIH’s PubChem

PubChem is one of the largest compound database on the WWW, because it does not contain direct information to suppliers, but to suppliers only via other catalog databases (e.g. ChemExper)

eMolecules

“eMolecules is the world’s most comprehensive openly accessible search engine for chemical structures. Each day, over 2,000 chemistry professionals visit our web site to find valuable information that helps them do their work more productively.”

Reference:

http://www.infonortics.com/chemical/ch06/slides/brandle.pdf

The above photo is from Internet

Definitions:

Theories:

Young Equation

Wenzel Equation

Applications:

Microfluidic applications in biotechnology:

Flat glass:

Notes:

“The chemical modification of surface forces alone can typically lead to water contact angles of up to 120^o by using fluoropolymeric coatings or silane layers, but not more. To reach the extreame values of the contact angle near 180^o, a second ingredient has to come into play: surface structure.”

“Wettability is improved by roughness for a hydrophilic surface, but get worse for a hydrophobic one.”

“The ultraphobic route to glass surfaces presents a fundemental problem: the substrate roughness may hinder transparency owing to scatter losses. To avoid this, the critical requirement is that the surface corrugations do not affect the light waves passing throuth them.”

“The biggest problem facing all self-cleaning or contaminant-free surface applications are ageing and decay.”

Reference:

1. Blossey, R., ‘Self-cleaning surfaces - Virtual realities’, Nat. Mater. , vol. 2, no. 5, 301-306 (2003).
2. Feng, X. . J. Jiang, L., ‘Design and Creation of Superwetting/Antiwetting Surfaces’, Advanced Materials , vol. 18, no. 23, 3063-3078 (2006).
3. Wang, S., Song, Y. Jiang, L., ‘Photoresponsive surfaces with controllable wettability’, J. Photochem. Photobiol. C Photochem. Rev. , vol. 8, no. 1, 18-29 (2007).
4. Roach, Paul, Shirtcliffe, Neil J. Newton, Michael I., ‘Progess in superhydrophobic surface development’, Soft Matter , vol. 4, no. 2, 224-240 (2008).

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From http://www.thermo.com/com/cda/landingpage/0,10255,1481,00.html