Thermal peformance of miniature loop heat pipe operating under different heating modes

In the new generation microprocessors, it is observed that the power density over the active surface can vary from uniform to non uniform modes depending on the clock speed and the processing load on the chipset. The latter mode of operation can result in hot spots on the microprocessors that can result in the increase of the local temperature above the permissible limit and ultimately in the failure of the electronic device. In order to propose a solution for this problem a miniature loop heat pipe (mLHP) with the flat disk shaped evaporator, 30 mm in diameter and 10 mm thick, was developed. The proposed mLHP was tested under uniformly as well as non-uniformly heating mode. In the uniform heating, the entire active area of the evaporator was heated while in the non-uniform mode only 14% of the evaporator active area was heated locally. The thermal performance of the mLHP under these heating modes was compared on the basis of the evaporator wall temperature and thermal resistance between different loop components. The results of the experiment help to classify mLHP as the viable thermal solution for the cooling of microprocessors with local hot spots and non-uniform heating pattern

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

A convenient one pot synthesis of substituted and unsubstituted 2, 4-diaryl-5-oxo-5,6,7,8-tetrahydro-2-chromens

368-371Anhydrous zinc chloride catalysed reactions of arylideneacetophenones 2a-c give 2, 4-diaryl-5-oxo-5, 6, 7, 8-tetrahydro-2-chromens 4a-c with 1, 3-cyclohexanedione. Under similar conditions arylideneacetophenones 2a-b and 2d-f react with 5, 5-dimethyl-1, 3- cyclohexanedione (dimedone) yielding 7, 7-dimethyl- 2, 4-diaryl-5-oxo-5, 6, 7, 8- tetrahydro-2-chromens 4d -h