Sulfidation treatment of molten incineration fly ashes with Na2S for zinc, lead and copper resource recovery.

The present study focuses on the conversion of heavy metals involved in molten incineration fly ashes to metal sulfides which could be thereafter separated by flotation. The sulfidation treatment was carried out for five molten incineration fly ashes (Fly ash-A to Fly ash-E) by contacting each fly ash with Na(2)S solution for a period of 10 min to 6h. The initial molar ratio of S(2-) to Me(2+) was adjusted to 1.20. The conversion of heavy metals to metal sulfides was evaluated by measuring the S(2-) residual concentrations using an ion selective electrode. The formation of metal sulfides was studied by XRD and SEM-EDS analyses. In the case of Fly ash-A to Fly ash-D, more than 79% of heavy metals of zinc, lead and copper was converted to metal sulfides within the contacting period of 0.5h owing to a fast conversion of metal chlorides to metal sulfides. By contrast, the conversion of about 35% was achieved for Fly ash-E within the same contacting period, which was attributed to a high content of metal oxides. Further, the S(2-) to Me(2+) molar ratio was reduced to 1.00 to minimize Na(2)S consumption and the conversions obtained within the contacting period of 0.5h varied from 76% for Fly ash-D to 91% for Fly ash-C. Finally, soluble salts such as NaCl and KCl were removed during the sulfidation treatment, which brought about a significant enrichment in metals content by a factor varying from 1.5 for Fly ash-D to 4.9 for Fly ash-A.

Sulfidation treatment of copper-containing plating sludge towards copper resource recovery.

The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio.

Sulfidation of zinc plating sludge with Na2S for zinc resource recovery.

A high amount of zinc disposed in the landfill sites as a mixed-metal plating sludge represents a valuable zinc source. To recover zinc from the plating sludge, a sulfidation treatment is proposed in this study, while it is assumed that ZnS formed could be separated by flotation. The sulfidation treatment was conducted by contacting simulated zinc plating sludge with Na(2)S solution at S(2-) to Zn(2+) molar ratio of 1.5 for a period of 1-48 h, while changing the solid to liquid (S:L) ratio from 0.25:50 to 1.00:50. The conversion of zinc compounds to ZnS was determined based on the consumption of sulfide ions. The reaction products formed by the sulfidation of zinc were identified by X-ray diffraction (XRD). As a result, it was found that the conversion of zinc compounds to ZnS increased with an increase in S:L ratio. A maximum conversion of 0.809 was obtained at an S:L ratio of 1.00:50 after 48 h. However, when the zinc sludge treated at S:L ratio of 1.00:50 for 48 h was subjected to XRD analyses, only ZnS was identified in the treated zinc sludge. The result suggested that the rest of zinc sludge remained unreacted inside the agglomerates of ZnS. The formation behavior of ZnS was predicted by Elovich equation, which was found to describe the system satisfactorily indicating the heterogeneous nature of the sludge.

Dissociation of impairment between spatial memory, and motor function and emotional behavior in aged rats.

We investigated changes in learning and memory in aged rats, in relation to motor function and emotional behavior. Male Kbl Wistar aged rats (108-weeks-old) were divided into two groups, memory impaired and non-impaired, based on performance during six training trials in the Morris water maze task. Aged rats with a goal latency longer than the mean plus the 99% confidence limit of young rats, were regarded as memory impaired, whereas those with a goal latency within the range of the 99% confidence limit of the mean of young rats, were considered as memory non-impaired. Although the performance of the memory impaired aged rats in the standard test of the Morris water maze improved after six re-training trials to the level of the non-impaired aged rats and young rats, working memory impairment was evident. There were no differences in motor function and emotional behavior between the impaired and non-impaired aged rats. These results suggest that deficits of learning and memory in memory impaired aged rats can be dissociated from changes in motor function and emotional behavior.

MR cisternography of the cerebellopontine angle: comparison of three-dimensional fast asymmetrical spin-echo and three-dimensional constructive interference in the steady-state sequences.

BACKGROUND AND PURPOSE: MR cisternography has been used as the noninvasive screening tool of the cerebellopontine angle. The purpose of this study was to directly compare two currently dominant types of sequences for heavily T2-weighted MR cisternography. METHODS: Three-dimensional fast asymmetric spin-echo (3D-FASE) sequences, which are 3D half-Fourier rapid acquisition with relaxation enhancement and 3D constructive interference in the steady-state (3D-CISS) sequences, were compared on a clinical 1.5-T MR unit using the same scan times. In five healthy volunteers, the contrast-to-noise ratio (C/N) between CSF and the cerebellum was measured at three locations. Then, for qualitative analysis, the quality of the labyrinth was scored on the original source multiplanar reformatted images, the virtual endoscopic images, and the maximum intensity projection (MIP) images. In 20 consecutive patients with suspected cerebellopontine angle tumors, visualization of the tumors was evaluated using 3D contrast-enhanced spoiled gradient-echo imaging as the standard of reference. RESULTS: Both sequences showed comparable mean C/N values; however, in qualitative analysis, the scores for 3D-CISS on the source, virtual endoscopic, and MIP images were significantly lower than those on the images obtained with 3D-FASE, owing to more prominent flow and magnetic susceptibility artifacts on the 3D-CISS sequences. In all subjects, discontinuity of the semicircular canals was seen on the virtual endoscopic and MIP images obtained with 3D-CISS, owing to susceptibility artifacts, but not on those obtained with 3D-FASE. All 12 tumors were detected by both sequences, but 3D-CISS gave one false-positive result. CONCLUSION: 3D-FASE is considered the method of choice because artifacts are reduced and specificity is increased.

Parotid gland papillary cystadenocarcinoma in a Fischer 344 rat.

A spontaneous parotid gland tumor with histomorphologic features characteristic of cystic and papillary growth was found in a 72-week-old F344 rat. The tumor had a prominent cystic appearance and invasive growth into the dermis beyond the muscular layer of the skin. The cyst walls were lined by a single layer of cuboidal to tall columnar epithelium with prominent papillary projections continuous with the cyst lining. The tumor cells had mucoid, pale cytoplasm and medium to large nuclei. The myoepithelium did not appear to be associated with the tumor cysts and the papillae. Atrophic parotid gland tissues were seen between cysts and in the periphery of the cystic lesions. In light of these findings, the tumor was diagnosed as papillary cystadenocarcinoma of parotid gland; this is the first description of a salivary gland papillary cystadenocarcinoma in a rat.

Increases in discontinuous rib cartilage and fused carpal bone in rat fetuses exposed to the teratogens, busulfan, acetazolamide, vitamin A, and ketoconazole.

Skeletal changes induced by treatment of pregnant rats with four potent teratogens, busulfan, acetazolamide, vitamin A palmitate, and ketoconazole, were evaluated using Alizarin Red S and Alcian Blue double-staining to investigate the relationship between drug-induced skeletal malformations and cartilaginous changes in the fetuses. Pregnant rats (N = 8/group) were treated once or twice between gestation days (GDs) 10 to 13 with busulfan at doses of 3, 10, or 30 mg/kg; acetazolamide at 200, 400, or 800 mg/kg; vitamin A palmitate at 100,000, 300,000, or 1,000,000 IU/kg; or ketoconazole at doses of 10, 30, or 100 mg/kg. Uterine evaluations and fetal external and skeletal examinations were conducted on GD 20. Marked skeletal abnormalities in ribs and hand/forelimb bones such as absent/ short/bent ribs, fused rib cartilage, absent/fused forepaw phalanx, and misshapen carpal bones were induced at the mid- and high-doses of busulfan and acetazolamide and at the high-dose of vitamin A palmitate and ketoconazole. Increased incidences of discontinuous rib cartilage (DRC) and fused carpal bone (FCB) were observed from the low- or mid-dose in the busulfan and acetazolamide groups, and incidences of FCB were increased from the mid-dose in the vitamin A palmitate and ketoconazole groups. Therefore, DRC and FCB were detected at lower doses than those at which ribs and hand/forelimb malformations were observed in the four potent teratogens.

Study on reaction kinetics and selective precipitation of Cu, Zn, Ni and Sn with H2S in single-metal and multi-metal systems.

Determination of reaction kinetics and selective precipitation of Cu, Zn, Ni and Sn with H(2)S in single-metal and multi-metal systems were studied to develop a process of metal recovery from plating wastewater. As samples, single-metal model wastewaters containing Cu, Sn, Zn or Ni, and multi-metal model wastewater containing Cu-Zn-Ni or Sn-Zn mixtures were used. In both single-metal and multi-metal systems, the pH value was precisely controlled at a value of 1.5 for CuS and SnS precipitation, 4.5 for ZnS precipitation and 6.5-7.0 for NiS precipitation. Subsequently, the sulfidation of Cu, Sn, Zn and Ni was evaluated. It was found that an amount of H(2)S equimolar to a given metal was sufficient to achieve almost complete precipitation of the particular metal. Further, the selectivity of metal precipitation was found to be higher than 95% in the Cu-Zn-Ni multi-metal system and higher than 91% in the Sn-Zn system. It was also found that the sulfidation reaction proceeded in accordance with Higbie's penetration theory and reaction rate constants and mass-transfer coefficients under various experimental conditions were determined. Finally, the reaction rate constants obtained in single-metal and multi-metal systems were found to be almost the same indicating that the precipitation of a particular metal was not significantly affected by the presence of other components.

Further evidence of prolactin production from human decidua and its transport across fetal membrane.

In this study the human decidua, chorion and amnion were incubated for short term. Only the decidua, secreted much prolactin clearly among them as a function of time. When the amounts of prolactin in the maternal blood, cord blood obtained from umbilical vein, or those released into decidual incubation medium were compared with the amniotic fluid prolactin levels, only the decidual prolactin correlated significantly with the amniotic fluid prolactin. The urine obtained from newborns showed a low concentration of prolactin. These results suggest that the origin of prolactin present in the amniotic fluid is not from the mother or fetus, but from the decidua which has the ability of producing prolactin, and that prolactin secreted from this tissue may be transported into the amniotic fluid through the fetal membrane and accumulated there.

A clinicopathologic study on adenomyosis uteri.

Clinicopathologic investigations were carried out on 51 cases that had received hysterectomy and had been diagnosed histologically as adenomyosis uteri during a 4-year period since 1977, and the following results were obtained: 1) adenomyosis uteri was found in 51 out of 418 hysterectomized patients, the incidence being 12.2%, 2) 74.5% of the cases with adenomyosis uteri were in the fifth decade, the average being 44.8 years old, 3) 94% of the cases were gravidous, 82% being parous. The incidence of sterility was low in the case of adenomyosis uteri, 4) major symptoms of the adenomyosis uteri were dysmenorrhea and hypermenorrhea, and these symptoms increased in frequency as the degree of adenomyosis uteri progressed, 5) fibroid was a complication of the adenomyosis uteri in 25 cases, while endometrial carcinoma was observed in only 1 case, 6) the ectopic endometrium also showed the same changes in secretory conditions and menstrual changes as the surface endometrium, 7) many cases showed a difference in periodicity between the menstrual cycle and endometrial cycle, and also between the menstrual cycle and the ovarian cycle, and 8) in the ovary, luteinized cysts were observed in 21, 6% of all the cases, corpus luteum persistence in 27.5%, stromal hyperplasia in 33.3%, and follicular cysts in 64.7%. Both the stromal hyperplasia and the follicular cysts were found to increase in frequency as the degree of adenomyosis uteri advanced.

Endometrial carcinoma and its precancerous lesions related with glandular cystic hyperplasia.

Morphological investigations were carried out on 184 cases with GCH and related diseases, and the following results were obtained: 1. Pure GCH was observed in 112 cases (60.9%), GCH with ADH in 56 cases (30.4%), and GCH with ATH in 11 cases (6.0%). ECA related with GCH was found in 5 cases (2.7%). 2. It was suggested that GCH can serve as a remote precursor of ECA. Namely, GCH in some cases was found to develop into ECA apparently through the change from ADH to ATH. 3. It was morphologically observed that in GCH, both glandular epithelium and stromal cells were proliferated by being stimulated by estrogen, and such a proliferation was interrupted by an estrogen antagonist, progesterone. On the other hand, in the case of ATH, the growth of stroma was generally decreased and the proliferation of glandular epithelium became predominant. Moreover, the action of progesterone was minimum in ADH and ATH. These findings indicate that precancerous lesions such as ADH and ATH are those capable of developing easily into carcinoma.

Continuous infusion of beta-amyloid protein into the rat cerebral ventricle induces learning impairment and neuronal and morphological degeneration.

To investigate the toxicity of beta-amyloid protein, a component of the senile plaques in Alzheimer's disease, it was infused into the cerebral ventricle of rats for 14 days by a mini-osmotic pump. Performances in the water maze and passive avoidance tasks in beta-amyloid protein-treated rats were impaired. Choline acetyltransferase activity significantly decreased in the hippocampus both immediately and 2 weeks after the cessation of the infusion. However, the learning impairment was recoverable 2 weeks after cessation of the infusion. Both immediately and 2 weeks after the cessation of the infusion, glial fibrillary acidic protein immunoreactivity increased. Furthermore, beta-amyloid protein altered the staining in the nuclei of hippocampal cells for only 2 weeks after the cessation. These results suggest that beta-amyloid protein produces some damage in the central nervous system in vivo.

A case of ovarian endometrioid carcinoma and malignant transformation of adenomyosis uteri.

The perusal of literatures revealed that simultaneous malignant transformation of predisposing ovarian endometrioid tumor and uterine adenomyosis is a rare occurrence. A case report of endometrioid carcinoma in the right ovary and malignant transformation of adenomyosis in the uterus in a 52-year-old female was described. Both foci were histologically classified as mature adenoacanthoma and separately originated from the so-called endometriosis. There is no continuity associated with metastasis between the two carcinoma foci.

Retroperitoneal giant tumor formed by migrating polyembryoma with numerous embryoid bodies from an ovarian mixed germ cell tumor.

We report on a very rare case of retroperitoneal tumor formed by migrating polyembryoma with numerous embryoid bodies from an ovarian mixed germ cell tumor. It was successfully removed combined with artificial replacement of the aorta following chemotherapy. We also discussed the fate of embryoid bodies following metastasis or chemotherapy.

Bizarre leiomyoblastoma (epithelioid leiomyosarcoma) of the uterus--a case with a malignant clinical course.

A case of a bizarre leiomyoblastoma (epithelioid leiomyosarcoma) which developed in the uterus of a 64-year-old woman and showed a malignant clinical course was reported. Histologically, the tumor in the present case had a number of bizarre giant cells, while the portion showing an epithelioid pattern was minor. Since the existence of an intimate inter-relationship between tumor cells and the smooth muscles of the blood vessel wall was a characteristic finding in the present case, a possible role of vascular smooth muscles as a tumorigenic matrix was suggested. Because of the closure of the internal os of the uterus by the tumor, the uterus had a cystomorphous appearance, and contained about 800ml of intrauterine fluid. The highest number of mitosis observed was 7 per 10 HPF. In view of abundant existence of intranuclear cytoplasmic inclusions, the malignancy of the present case was strongly suspected from a histological diagnostic point of view. The patient died 5 months after surgery because of metastases to the lumbar vertebra and to the lung.