Anti-parallel

Full wave similar to Figure 6.24(a) configuration (a), using tw o diodes in anti-parallel per phase instead of thyristors or in the form of a centre-point configurtition. 

Fully controlled thyristor inverter in anti-parallel to feedback energy... 

In TSCs the thyristors are used in anti-parallel to switch a capacitor bank ON or OFF but without any phase angle control. A TSC therefore does not by itself generate any harmonics, unlike a TCR. 

The number of thyristors in series, each selected for an impulse voltage of a little less than the impulse voltage with.stand level of the terminal equipment (Table 11.6) can effectively limit the switching overvoltages within desired safe limits. Then connecting them in anti-parallel will mean that the voltage will be forward for either of... 

The two peptides form a symmetrical dimer stabilized by four hydrogen bonds (red dashes) and hydrophobic contacts. The two monomers form a four-stranded, anti-parallel pleated sheet. 

For those applications where high efficiency is important, synchronous rectification may be used on the higher current (power) outputs. Synchronous rectifier circuits are much more complicated than the passive 2-leaded rectifier circuits. These are power MOSFE B, which are utilized in the reverse conduction direction where the anti-parallel intrinsic diode conducts. The MOSFET is turned on whenever the rectifier is required to conduct, thus reducing the forward voltage drop to less than O.f V. Synchronous rectifiers can be used only when the diode current flows in the forward direction, that is in continuousmode forward converters. 

Figure 3 shows the calculated conductivity for one of the channels when the cobalt moments on either side of the copper layer are aligned anti-parallel. The spin channel for which the conductivity is shown in Figure 3 is locally the majority channel in the cobalt layer to the left of the copper (spin parallel to the Co moment) and locally minority to the right of the copper (electron spin anti-parallel to the local Co moments). The non-local conductivity for the other spin channel for the case in which the cobalt moments are antiparallel is the mirror image of the conductivity shown in Figure 3. 

Note that majority electrons that are accelerated by the electric field in one of the cobalt layers contribute to the current, not only in that layer (I = J) but in other layers as well, including the copper layers and the cobalt layers on the other side of the copper. On the other hand, minority electrons that are accelerated by a field in one of the cobalt layers contribute very little to the conductivity in the copper or in the cobalt on the other side of the copper. For anti-parallel alignment of the moments, electrons that are accelerated by the field in one cobalt layer contribute to the current in that layer and in the cobalt, but not in the other cobalt layer. The difference in the lolal current due to both channels between parallel and anti-parallel alignment is almost entirely non-local. It comes from those electrons that are accelerated by the applied electric field in one cobalt layer and propagate across the copper to the other cobalt layer where they contribute to the current. It is clear from Figures 1-4 that this process occurs primarily for majority electrons and for the case of parallel alignment. 

The non-local nature of the contributions to the GMR can be seen in Figure 4 which shows the difference in the total non-local conductivity between the cases of parallel and anti-parallel alignment of the cobalt mom its. Thus Figure 4 shows the sum of the conductivities in Figures 1 and 2 minus the sum of the conductivities in Figure 3 and its mirror image. Note that the contributions to Ao are entirely non-local. 

Figure 4 Giant Magnetoconductance. The change in the non-local layer dependent conductivity between parallel and anti-parallel alignment of the cobalt moments. For this case of strong scattering in both the cobalt and copper, contributions to the GMR come from electrons that are accelerated in one cobalt layer and contribute to the current in the other.

Tumor Necrosis Factor. Figure 1 Homotrimeric structure of soluble TNF (51 kDa). TNF monomers (17kDa) in individual subunits fold into a jelly role pattern that is composed of anti-parallel (3 strands separated by intervening loop regions, which are represented by green, red, or blue color. 

Entry Backbone modijication RNA anti parallel) (DNA antiparallel)... 

We have sequenced RpII and studied the structures of RpII and RpIII in solution by 2D-NMR and distance geometry methods. The resonances are almost completely assigned, and secondary and tertiary structures have been determined. Our results indicate that Rp toxins have a four strand anti-parallel )9-sheet and no a-helix. Functionally important residues are found to be located in looped regions of the... 

It is a supposition that the )9-sheet structure of neurotoxin is an essential structural element for binding to the receptor. The presence of -sheet structure was found by Raman spectroscopic analysis of a sea snake neurotoxin (2). The amide I band and III band for Enhydrina schistosa toxin were at 1672 cm and 1242 cm" respectively. These wave numbers are characteristic for anti-parallel -sheet structure. The presence of -sheet structure found by Raman spectroscopic study was later confirmed by X-ray diffraction study on Laticauda semifasciata toxin b. 

The first illustration of the concept of a partition function is that of a two-level system, e.g. an electron in a magnetic field, with its spin either up or down (parallel or anti parallel to the magnetic field) (Fig. 3.2). The ground state has energy Eq = 0 and the excited state has energy Ae. By substituting these values in Eq. (3) we find the following partition function for this two-level system ... 

The motion of hydronium and hydroxyl ions leaves molecules oriented against the apphed electrical field. The molecular dipole moment is then anti-parallel to the field. If bonding defects are passed by either of the hydronium and hydrojgrl ions, the molecular dipoles are left parallel to the field. Bonding defects dominate the polcuization in pure ice because they... 

Intramolecular reactions can also occur between carbonyl groups and allylic silanes. These reactions frequently show good stereoselectivity. For example, 7 cyclizes primarily to 8 with 4% of 9 as a by-product. The two other possible stereoisomers are not observed.98 The stereoselectivity is attributed to a preference for TS 7A over TS 7B. These are both synclinal structures but differ stereoelectronically. In 7A, the electron flow is approximately anti parallel, whereas in 7B it is skewed. It was suggested that this difference may be the origin of the stereoselectivity. 

Very recently the trans- [Pt(NH3)2Cl2] isomer has been shown to promote the formation of some highly unusual multiple strand nucleic acid structures (28). A parallel-stranded DNA duplex, psPtDNA, has been prepared which incorporates a frarcs-Pt(NH3)2+ crosslink. The pla-tinated strands were synthesized through the series of reactions illustrated in Fig. 3. The initial mono-functional G N7 adduct is formed at pH 3.5 by addition of rans-[Pt(NH3)2(H20)Cl]+ to the pyrimidine-rich sequence 5 -d(T4CT4G). After the pH is increased, normal anti-parallel duplex formation occurs upon addition of the complementary purine-rich strand, 5 -d(A4GA4G). This intermediate anti-parallel stranded... 

The spin moments of both USe and UTe are aligned anti-parallel to the magnetic field. That is to say, the whole magnetization is dominated by the orbital moments of these compounds. 

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