Collective pinning

A. Tanguy, M. Gounelle and S. Roux, From Individual to Collective Pinning Effect of Long-range Elastic Interactions, Phys. Rev., E58, 1577 (1998). 

Ovchinnikov (1974, 1979) proposed the collective pinning theory, which introduced certain collective actions of several defects over a certain correlation length or volume for the first time, a theory that represents the basis for most flux-pinning considerations in high-temperature superconductors because of their generally weak pinning potentials. 

This procedure is used to separate crystallized product from solvent or to remove crap and solids from a liquid. Figure 8 shows the proper apparatus to use. The collecting flask is called a side arm flask and to that extended nipple (tee heel) is attached a vacuum source. The thing that is shoved through the rubber stopper is called a Buchner funnel and is usually made of white porcelain or, preferably, PP. The Buchner funnel, when viewed from above, can be seen to have lots of pin holes in the bottom surface of its reservoir. Over this surface is layered a single sheet of rounded filter paper or paper towel. 

Low resistivity can sometimes be a problem, if the resistivity is below lO" n-cm, the collected particles are so conductive that their charges leak to ground faster than they are replenished bv the corona. The particles are no longer electrostatically pinned to the plate, and... 

An alternating-current electrode svstern referred to in the indiisti v as a wiper is often installed in the nonconductor product-collection section behind each drum. The function of the wiper is to use an ac corona to neutralize the charge on the nonconductor particles pinned... 

Mfldelchen, n, little needle (or pin), I adel-eisenerz, n., -eisenstein, m. needle iron ore (gdthite in acicular crystals), -erz, n, needle ore (aikinite in acicular crystals), -faser, /, acicular fiber. nadelfSrmig, a. needle-shaped, acicular. Madel-holz, n. conifers (collectively), esp, pines and firs wood of conifers, soft wood, -holzer, n.pl. (Bot.) Finales, Coniferae, -holzkohle,/. soft-wood charcoal, -holzteer, m, soft-wood tar, (loosely) pine tar. -holzzellstoff, m. cellulose (or pulp) from conifers, nadelig, a. needly, acicular. 

A mixture of 100 g of this solid and 1 liter of acetic anhydride was stirred and heated under reflux for 1.5 hours and then allowed to stand for 18 hours at room temperature. The excess acetic anhydride was removed in vacuo, and the residue was treated with one liter of water and ice and sufficient sodium bicarbonate to make neutral. The solid was collected, sucked dry on the filter, and triturated with hot ethanol. The ethanol solution on cooling gave 30.8 g of 4-acetyl-7-chloro-1,2,3,4-tetrahydro-1-methyl-5H-1,4-benzodiaze-pin-5-one. 

Energy-dispersive spectrometry (EDS) is a technique of X-ray spectroscopy that is based on the simultaneous collection and energy dispersion of characteristic X-rays. Typical ED detectors are thermoelectrically cooled semiconductors (usually operated at 77 K), PIN diodes,... 

This chapter will cover the efforts that have been made to use the principles of combinatorial chemistry in the development of new catalysts. In the last few years there has been a lively discussion of what is the correct definition of combinatorial chemistry. Some workers reserve the term combinatorial chemistry for the synthesis and evaluation of mixtures. For the purpose of this chapter, we will employ a liberal interpretation of the term. Since one of the definitions of the word combinatorial is, of or involving combinations (14), we will use the term to include what may be referred to as parallel synthesis. In parallel synthesis, one generates a combination of molecules, be they in separate vials or on separate pins. One view may be that a collection of vessels represents a combination of molecules. It is for this... 

A number of clinical tests are available to detect kidney damage. The clinician examining a patient or the toxicologist monitoring an animal toxicity stndy collects urine and blood samples. Indications of kidney damage (which, of course, for the human patient could be related to many factors other then chemical toxicity) include urinary excretion of excessive amonnts of proteins and glucose, and excessive levels in the blood of unexcreted waste products such as urea and creatine. A number of additional kidney function tests are available to help pin down the location of kidney dysfunction. 

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