In order to improve the oral bioavailability (BA) of 2-butyl-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimid azole - 7-carboxylic acid (3: CV-11194) and 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4- yl]methyl]-1H-benzimidazole-7-carboxylic acid (4: CV-11974), novel angiotensin II (AII) receptor antagonists, chemical modification to yield prodrugs has been examined. After selective tritylation of the tetrazole rings in 3 and 4, treatment of N-tritylated benzimidazole-7-carboxylic acids (6, 7) with a variety of alkyl halides, followed by deprotection with hydrochloric acid, afforded esters of 3 and 4. Mainly 1-(acyloxy)alkyl esters and 1-[(alkoxycarbonyl)oxy]alkyl esters, double ester derivatives, were synthesized. Their inhibitory effect on AII-induced pressor response in rats and oral BA were investigated. (Pivaloyloxy)methyl and (+/-)-1-[[(cyclohexyloxy)-carbonyl]oxy]ethyl esters of 3 and 4 showed marked increases in oral bioavailability which significantly potentiated the inhibitory effect of the parent compounds on AII-induced pressor response. Among them, (+/-)-1-[[(cyclohexyloxy)carbonyl]oxy]ethyl 2- ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimida zole- 7-carboxylate (10s, TCV-116) was selected as a candidate for clinical evaluation.

The spin-orbit torque switching of ferrimagnetic Gdx(Fe90Co10)100−x films was studied for both transition metal (TM)-rich and rare earth (RE)-rich configurations. The spin-orbit torque driven magnetization switching follows the same handedness in TM-rich and RE-rich samples with respect to the total magnetization, but the handedness of the switching is reversed with respect to the TM magnetization. This indicates that the sign of the spin-orbit-torque-driven magnetic switching follows the total magnetization, although transport based techniques such as anomalous Hall effect are only sensitive to the transition metal magnetization. These results provide important insight into the physics of spin angular momentum transfer in materials with antiferromagnetically coupled sublattices.Magnetization dynamics at interfaces has been investigated extensively over the last three decades 1-3 . In that context 'spin-orbit torque' (SOT) has received a lot of interest recently. Here, a charge current in a heavy metal is converted into a spin current via spin-orbit coupling and injected into an adjacent ferromagnet 4-7 . The transfer of angular momentum from the spins to the ferromagnet causes a torque on the magnetization which can switch the magnet 6,7 . To date, most studies of SOT have concentrated on 3d ferromagnets such as Co 4,6,8,9 FeCo 10 , FeCoB 11-13 , FePd 14 or transition metal rich ferrimagnetic alloys such as TbFeCo 15 . Here we report SOT switching of ferrimagnetic GdFeCo alloys with both rare earth (RE) rich or transition metal (TM) rich configurations with bulk perpendicular magnetic anisotropy (PMA) at room temperature.Our study is based on Gd x (Fe 90 Co 10 ) 100−x thin films, where the antiferromagnetic ordering between Gd 4f and FeCo 3d magnetic moments is mediated by Gd 5d electrons via 4f -5d exchange interaction and 3d-5d hybridization 16,17 and indirect RKKY conduction band exchange. The magnetic properties of Gd x (Fe 90 Co 10 ) 100−x can be varied by changing the composition x. A comparison between TM-rich and RE-rich samples allows us to conclude that the anomalous Hall effect (AHE) changes sign for these two different samples, in accordance with literature 18-21 , while the SOT-driven magnetic switching has the same sign in both samples. Further, the effective magnetic fields, induced by damping-like and field-like SOT, do not show any change in the sign.Ta (10)/Gd x (Fe 90 Co 10 ) 100−x (5)/SiN(5) films (thickness in nm) were grown by RF magnetron sputtering on thermally oxidized silicon substrates with compositions x = 21 (TM-rich) and x = 28 (RE-rich). The base pressure during deposition was lower than 1 × 10 −8 Torr. The SiN overlayer is used to prevent oxidation. After growth, PMA was confirmed with magnetometry. Hall bar mesa structures with a width of 20 µm were patterned using optical lithography and ion milling. The layout of the sample and the measurement setup are shown in Fig. 1. DC or AC currents are applied along the x-direction while the transverse voltage is measured. The orientatio...

Silver-sheathed BiPbSrCaCuO wires were f a b r ic a t e d t h r o u g h t h e p o w d e r -i n -t u b e method. Jc-B p r o p e r t i e s , microstructures and Jc-strain properties wcre evaluated. Prototypes of coils and current leads were made and tested successfully.Critical current densities a t 77.3 K were 4 . 7~1 0~A/cm2 in a zero magnetic f i e l d , 3 . 1~1 0~ A/cm2 a t 0.1 'I'csla and 1 . 1~1 0~ A/cm2 a t 1 Tesla. In liquid He, 4.2 K, these wires can c a r r y 1 . 0 3~1 0~ A/cm2 a t 23 Tesla. J c and .Jc-B enhancements a r e due t o grain boundary improvements. Detailed investigation of Jc-B characteristics in magnetic fields, especially increasing and dccreasing f i e l d s , revealed t h a t h i s t o r y e f f e c t behaviors caused by weak l i n k s disappeared with improvements of grain boundary characteristics a t both temperatures. 1296 multifilamentary wires were shown t o sustain over 70 % of J c o even a f t e r a s t r a i n of up t o 0.GG % repeated 10 times. These r e s u l t s show f u t u r e possibilities of f l e x i b l e c a b l e s and r e a c t & windprocessed magnets. P r o t o t y p e s of c o i l s and c u r r e n t leads were fabricated using 20 m long wires. One c o i l showed critical currents of 54.2 A a t 77.3 K and 367 A a t 4.2 K. This coil generated B, of 142 Gauss a t 77.3 K and 87G Gauss a t 4.2 K. Critical c u r r e n t p r o p e r t i e s were investigated with back-up fields of up t o 990 Gauss a t 77.3 K and 3.7 Tesla a t 4.2 K. A prototype of react & wind-processed coil was demonstrated using o v e r 4 m I o 11 g mu 1 t i f i 1 am e n t a r y w i r e s , a n d s u c c e s s f u 1 l y produced enough magnetic f i e l d t o r o t a t e c o p p e r windings between s t e e l cores. 50 cm long c u r r e n t leads were made and t e s t e d a t 77.3 K and proved t o carry 242 A, showing overall current d e n s i t y of 2000 A/cm2 including silver-sheath.

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In this paper, multi-walled carbon nanotubes (MWCNTs) were successfully immobilized on the surface of a glassy carbon electrode by mixing with horse-radish peroxidase (HRP). The electrochemical behavior of H2O2 was also studied with the MWCNTs-HRP modified electrode as a working electrode. The MWCNTs-HRP modified electrode showed excellent response of reduction current for the determination of H2O2 at the potential of -300 mV (vs. Ag/AgCl). We assembled the MWCNTs-HRP modified electrode in a thin-layer flow cell and the H2O2 solution was continuously introduced into the cell with a syringe pump. We optimized the sensitivity of the H2O2 sensor by adjusting the working potential and the pH of the buffer solution. The peak current increased linearly with the concentration of H2O2 in the range 3.0 x 10(-7) to approximately 2.0 x 10(-4) mol L(-1). The detection limit is 1.0 x 10(-7) mol L(-1) (S/N = 3). The interferences from ascorbic acid, uric acid and other electroactive substances can be greatly excluded since the sensor can be operated at -300 mV. Stability and reproducibility of the MWCNTs-HRP chemically modified electrode were also studied in this paper. Fabricated with glucose and lactate oxidase, the MWCNTs-HRP electrode was also applied to prepare the on-line glucose and lactate biosensors because of the high sensitivity for the determination of H2O2.