[en] Objective: To investigate the value of SWI sequence in diagnosis of DAI by analyzing the MRI images of DAI. Methods: The MRI data of 30 cases with DAI diagnosed by clinic were analyzed retrospectively. The signal intensity features and detection rate of lesions were compared in all sequences. Results: SET₁WI sequence had the lowest sensitivity, secondly was T₂WI sequence. DAI showed as long T₁ long T₂ signal. Some lesions could be detected with FLAIR, appearing as nodular or patchy hyperintensity. More lesions were detected with SWI sequence than with other sequences. DAI lesions mainly located in the junctional zone of cortex and medulla, basal ganglia, corpus callosum, brain stem and cerebellum. It appeared as needle tip, mottling, nodular hypointensity in SWI sequence. Conclusion: SWI can detect more lesions in cases with DAI than other sequences. It can be an additional sequence in MRI examination for the patients suspicioused with DAI. (authors)

[en] Objective: To evaluate susceptibility-weighted imaging for diagnosing developmental venous anomaly (DVA). Methods: The conventional MRI (30), SWI (30) and MRV (10) of 30 patients with diagnosis of DVA on MRI were retrospectively analyzed. Results: On unenhanced MRI draining veins were clearly demonstrated as hypointensity on T₁WI and T₂WI in 3 cases, hypointensity on T₁WI and hyperintensity on T₂WI in 5 cases. In 22 patients the draining veins were not seen. MRV showed the draining veins in all 10 patients. On contrast-enhanced MRI, medullary and draining veins were enhanced with the characteristic hyperintense caput medusa appearance. Hypointense caput medusa pattern was visible on SWI. Conclusions: The draining veins of DVA were not well shown on conventional MRI but clearly demonstrated on contrast-enhanced MRI and SWI. More medullary veins are visible on SWI, which is valuable for diagnosing DVA. (authors)

[en] Objective: To evaluate the MRI features of sacrococcygeal pilonidal sinus. Methods: MRI of 11 patients with surgically proven sacrococcygeal pilonidal sinus disease was reviewed. The MRI features including location, opening and extent of the fistula as well as the relationship with adjacent structures were recorded. Results: All patients had sacrococcygeal subcutaneous fistulae with openings between the 5th sacral and 1st coccygeal vertebrae. The fistulae were localized in the subcutaneous tissue (n = 3) or extended superiorly (n = 8) between the 2nd sacral and 2nd coccygeal vertebrae. The fistulae were 2.5 to 8.8 cm in length with T₁ iso-hypointense and T₂ hyperintense mural thickening and contrast enhancement. The contents of the fistulae were T₁ isohyperintense and T₂ hyperintense without enhancement. Edema was shown in the surrounding soft tissues. There was no extension to the spinal canal or anal canal. Hair was found in 4/11 cases by pathological examination, but none was detected on MRI. Conclusion: Sacrococcygeal pilonidal sinus can be shown clearly on MRI for definitive diagnosis. (authors)

[en] Highlights: ► Electropolishing was used to obtain smooth surfaces on Ni5W substrates for the preparation of YBCO coated conductors without obvious change of the textures of these Ni5 W substrates. ► Combining the phenomena observed during experiments and electropolishing theories, the electropolishing mechanism in this system has been studied, which is different with that on Ni metals due to the additional tungsten. ► In our theory, H₂WO₄, functioning as the viscous film, plays more important role during the electropolishing than NiO in the selective dissolution. - Abstract: The application of NiW substrates for YBCO coated conductor is hindered due to their roughness of surfaces. It was demonstrated that the smooth NiW substrate surfaces can be obtained through electropolishing in a sulfuric acid electrolyte. In this paper, the parameters in the electropolishing process, such as electrolyte temperature, current density and time, are optimized so as to attain the best surface brightness measured by an atomic force microscopy. The e1ectropolishing mechanism was discussed on the film generated during the electropolishing process. The results suggest that the electropolishing behavior of NiW alloy is under mass-transfer control and H₂WO₄ is the governing factor for the film formation mechanism during anodic dissolution.

[en] Ni"2"+-doped Ag_3PO_4 (Ni"2"+-Ag_3PO_4) photocatalysts with superhigh activity for photodegradation of organic pollutants were prepared by a simple hydrothermal method. The photocatalysts were characterized with X-ray powder diffractometry, transmission electron microscopy, ultraviolet–visible absorption spectroscopy, X-ray photoelectron spectroscopy, measurement of total organic carbon, and electron paramagnetic resonance spectrometry. The photocatalysts were evaluated by methyl orange (MO) photodegradation experiments under visible light irradiation (λ > 420 nm). Comparative analysis showed the optimal doping dosage was 0.05 mol/L Ni"2"+. The optimal Ni"2"+-Ag_3PO_4 has an MO photodegradation rate constant four times larger than pure Ag_3PO_4. The photocatalytic ratio of 40 mg/L MO over the optimal Ni"2"+-Ag_3PO_4 after 10 min is 89%, which indicates excellent photocatalytic ability in high-concentration MO solutions. The Ni"2"+ doping into Ag_3PO_4 can increase the level of band gap, and accelerate the utilization of photons and the separation of photo-generated charges. Therefore, the Ni"2"+ doping into Ag_3PO_4 is responsible for the enhancement of photocatalytic ability. - Highlights: • Ni"2"+-modified with higher photodegradation ability was synthesized. • ·OH radicals were the main active species in the oxidation of MO. • The doping of Ni"2"+ in Ag_3PO_4 is responsible for the enhanced activity.