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2,5-Bis(p-substituted phenyl)-1,3-oxathianes (5), new liquid crystal compounds, and some corresponding 1,3-dioxanes were synthesized by the acetal formation reaction. The mesomorphic behaviors of compounds 5 were compared with those of the corresponding 1,3-dioxanes and 1,3-dithianes. Compounds 5 exhibited the lowest transition temperatures between nematic and isotropic phases. This seems to originate in the bend at the 1,3-oxathiane ring containing two heteroatoms, oxygen and sulfur, different in size. Compounds 5 also tend to exhibit supercooling states in nematic phase.

Laboratory leaching experiments were conducted to ascertain the effectiveness of acidic solutions of thiourea, CS (NH2)2, for dissolving gold from finely disseminated gold ore containing much of hematite and pyrite. The ore tested was from the Cimanggue ore body of the West Jampang district, Indonesia.From the results obtained in the present study, lixiviation was shown to be dependent on thiourea concentration, ferric sulphate concentration, sulphuric acid concentration, leaching time, and temperature. In an ambient temperature, optimum conditions were 100 g/l of thiourea, 50 g/l of sulphuric acid, and 2 g/l of ferric ion, for 12 hours. On the other hand, when temperature increased up to 60°C, the added concentration of thiourea decreased to 40 g/l for 6 hours to achieve 100% lixiviation for gold.

Extraction of metal ions from the aqueous-organic solution containing dimethyl formamide(DMF), dimethyl sulfoxide(DMSO) and acetonitrile(AN) was investigated by using di-2-ethylhexyl-phosphoric acid(D2EHPA) as an extractant. The organic phase was a binary solution of D2EHPA and n-hexane, or D2EHPA and toluene, while the polar phase was a three component solution of metal salt, non-aqueous solvent and water. The extracted metal ions were Cr(III), Fe(III), Al, Cu, Ni, Co(II), Mg and Ag. The extraction behaviors may be explained by the solvation ability of non-aqueous solvents, the decrease in distribution of the extractant and extract into the organic phase, and the interaction between the extractant and non-aqueous solvents due to the dissolution of non-aqueous solvents in the organic phase.

ABSTRACT The extraction of Nb and Ta from acid solutions with bis-2-ethylhexyl acetamide and the stripping of these metals with sulphuric acid solutions were investigated. The organic phase was a binary solution of bis-2-ethylhexyl acetamide and xylene, while the aqueous phase was composed of hydrofluoric acid solution or hydrofluoric-sulphuric acid solution containing 3.5-13 Kg/m3 Nb and 5-10 Kg/m3 Ta. Sulphuric acid, hydrofluoric acid and nitric acid were used as salting out agents to understand the effect on the extraction. Niobium and tantalum were not sufficiently extracted from hydrofluoric acid solutions, whereas the extraction of both metals remarkably increased with an addition of sulphuric acid to the aqueous phase. Both metals were completely co-extracted under the aqueous condition of 6N hydrofluoric acid and 8N sulphuric acid. The stripping occurred for both metals with high efficiency when water or dilute sulphuric acid was used as a stripping agent. The increase in sulphuric acid c...

Various symptoms in obstructive arterial disease seem to be derived from ischemia due to a decreased blood flow in the peripheral tissues. Diagnostic imaging is usually used to determine the pathological condition of the disease. Determination of tissue blood flow, however, is a more accurate diagnostic method. By using the electrochemical hydrogen clearance method, which is less invasive, tissue blood flow was determined at the ischemic gastrocnemius muscle during rest and exercise, before and after revascularization. With regard to the site of obstruction, tissue blood flow was found to be lower in the peripheral region than in the central. The degree of increase in tissue blood flow during exercise was also lower in cases of obstruction in the peripheral region. Comparison of blood flow before and after revascularization demonstrated the usefulness of determining local tissue blood flow. In addition in cases of diabetic angiopathy, the degree of increase in tissue blood flow during exercise was low, even though there was no obvious obstruction on arteriography, suggesting a pathological nature different from that of arteriosclerosis.

A fifty-one-year-old Japanese man with Werner's syndrome underwent suc cessful reconstruction of peripheral arteries. His chief complaints were rest pain and intermittent claudication in the left lower extremity. Clinical manifestations included short stature, low body weight, stocky trunk with thin limbs, graying hair, peripheral muscular atrophy, a high-pitched voice, bilateral cataracts, typical facies, atrophic skin, and diabetes mellitus. Angiograms showed multi ple and severe calcified stenoses of the left femoropopliteal artery. The operative method used was semiclosed thromboendarterectomy. To the authors' knowledge, this case is the first surgical correction of a pe ripheral vascular lesion in a patient with Werner's syndrome.

2-(4'-Bromobenzoyl) benzoic acid was prepared from phthalic anhydride and bromobenzene, then 3-bromofluorenone was synthesized after passing through several steps. This was converted into 3-bromofluorene-9, 9-dichloride, dechlorination of which yielded 3, 3'-dibromobis (biphenylene) ethylene. By the Michael condensation reaction of the ethylene compound and 3-bromofl iorene, fluorene, etc., 3, 3', 3''-tribromotris (biphenylene) propane, 3, 3'-dibromotris-(biphenylene) propane, 3'-bromotris (biphenylene) propane, etc. were synthesized.Thermal decomposition of these compounds gave none of their isomers but the presences of 3, 3'-dibromobis (biphenylene) ethylene, -ethane, bis (biphenylene)-ethylene, etc. were confirmed in the thermal decomposition products.

Cardiac involvement in systemic sclerosis (SSc) is considerably frequent in autopsy, but the early identification is clinically difficult. Recent advantages in cardiac magnetic resonance (CMR) enabled to detect myocardial fibrotic scar as late gadolinium enhancement (LGE). We aimed to examine the prevalence and distribution of LGE in patients with SSc, and associate them with clinical features, electrocardiographic abnormalities and cardiac function. Forty patients with SSc (58 ± 14 years-old, 35 females, limited/diffuse 25/15, disease duration 106 ± 113 months) underwent serological tests, 12-lead electrocardiogram (ECG) and CMR. Seven patients (17.5 %) showed LGE in 26 segments of left ventricle (LV). LGE distributed mainly in the basal to mid inter-ventricular septum and the right ventricular (RV) insertion points, but involved all the myocardial regions. More patients with LGE showed NYHA functional class II and more (71 vs. 21 %, p 125 pg/ml). When cardiac involvement of SSc was defined as low LVEF, ECG abnormalities or high NT-proBNP, the sensitivity, specificity positive and negative predictive values of LGE were 36, 92, 71 and 72 %, respectively. We could clarify the prevalence and distribution of LGE in Japanese patients with SSc. The presence of LGE was associated with cardiac symptom, conduction disturbance and impaired LV/RV contraction.

Oxidation of 3-carene [1] with red lead in glacial acetic acid and acetic anhydride at 60±2°C gave; p-cymene-8-ol acetate [2] as main product and p-cymene [3], 3-carene-2-ol acetate [4], α-terpinyl acetate [5], 1, 1, 4-trimethyl-2, 4-cycloheptadiene-6-ol acetate [6] and trans-carvenyl acetate [7] as minor ingredients of the products.Oxidation compound [2] have a mild wood-like odor, and this may be useful as a stable perfume.

The pulmonary circulation is impaired by various diseases and the analysis of pulmonary blood flow has great clinical significance. 4D-Flow can visualize the velocity vectors of blood flow as streamline images. We aimed to study changes in flow pattern of pulmonary artery (PA) during a cardiac cycle