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This work presented influence of preparation conditions on immobilized molybdic acid on porous silica-alumina hollow sphere particles for acid-promoted hydrolytic hydrogen generation from ammonia borane. The main component of the immobilized molybdic acid was heptamolybdic acid with molybdic tetraoxide as the minor component. Their dispersion of the active heptamolybdic acid species depends on the amount of aqueous l -aspartic acid solutions adding during the immobilization of the active species on the hollow sphere particles, and treatment of the hollow sphere particles in aqueous ammonia solution. The immobilized active molybdic acid with high dispersion tended to exhibit high activity for acid-promoted hydrolytic hydrogen generation from ammonia borane.

We developed herein photoluminescent glass ceramics based on rare-earth ion-doped Na5YSi4O12-type materials according to the Na3+3xY1−x−yRySi3O9 (R: Sm3+, Eu3+, Dy3+, Tb3+) composition. Glass ceramics generally have the advantages of excellent chemical durability, heat resistance, and moldability over sintered ceramics. Upon irradiation with near-ultraviolet light, Sm3+-, Eu3+-, Dy3+-, and Tb3+-doped glass ceramics emit purplish orange, reddish orange, yellow, and green lights, respectively. The photoluminescent emission intensity of glass ceramics is higher than that of the original glasses, and the emission intensity depends on the crystalline phase. The highest emission intensity of various rare-earth ion-doped glass ceramics is obtained when the parameter y is equal to 0.03, 0.16, and 0.02 for the Sm3+-, Eu3+-, and Dy3+-doped glass ceramic samples, respectively. The internal quantum efficiency is 3%, 37%, 7% and 23% for the Sm3+-, Eu3+-, Dy3+-, and Tb3+-doped samples, respectively. Thus the Na superionic conducting Na5YSi4O12-type glass-ceramics were proved to have potentiality as novel phosphors.

A novel hole-transport material (HTM) based on an anthradithiophene central bridge named BTPA-7 is developed. In comparison to spiro-OMeTAD (2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene), the synthetic steps of BTPA-7 are greatly reduced from 6 to 3 and the synthetic cost of BTPA-7 is nearly a half that of spiro-OMeTAD. Moreover, BTPA-7 exhibits a relatively lower conductivity but higher hole mobility and higher glass transition temperature (Tg) than spiro-OMeTAD. Compared with the photovolatic performance for spiro-OMeTAD, FA0.85MA0.15PbI3 and MAPbI3 PSC devices based on BTPA-7 exhibit slightly lower PCEs with the values of 17.58% (18.88% for spiro-OMeTAD) and 11.90% (13.25% for spiro-OMeTAD), respectively. Nevertheless, a dramatically higher Jsc of PSC based on BTPA-7 is achieved, which arises from the higher hole mobility of BTPA-7. In addition, the relatively hydrophobic character of BTPA-7 eventually enhances the PSC device stability. Lower cost, higher hole mobility, higher Tg, satisfactory photovoltaic performance, and superior device stability of BTPA-7 can be utilized as a substitute for spiro-OMeTAD in PSCs.

We studied the influence of swelling agents on pore size distributions in the shell of porous silica-alumina hollow sphere particles for acid-promoted hydrolytic generation of hydrogen from ammonia borane. Their well-ordered porous shells were formed with micelle templates of cetyltrimethylammonium bromide on spherical polystyrene (PS) particle templates, and swelling agents were introduced into the micelle templates for expanding the pores. Non-polar agents (hexane and toluene) did not significantly influence the size of the pores, whereas, polar agents (1-dodecanol and 1-dodecylamine) effectively expanded the pores. The hollow sphere particles formed with 1-dodecylamine possessed narrow pore distribution with a high peak pore volume. The activity of the hollow sphere particles in the hydrolytic generation of hydrogen increased according to increasing pore size with a narrow distribution, and the hollow sphere particles formed with 1-dodecylamine showed an approximately five times higher TOF for the hydrogen evolution than those formed without a swelling agent.

This paper reports on the effect of pH on polymorphism of calcium carbonate (vaterite) formed in the CaCl2-Na2CO3-H2O reaction system. The initial pH of CaCl2 aqueous solution was adjusted to the initial pH 2.0–11.3 using HCl and NH3 aqueous solution. The initial pH was 6.5 without pH adjustment. When the reaction was carried out, amorphous calcium carbonate (ACC) was formed at the early stage of the reaction and crystallized to calcite and vatrite after 3 min of stirring. Formation ratio of vaterite at this time was 60％. Single-phase vaterite was formed at initial pH 2.0–2.5. Further, focusing on the pH during ACC crystallization. When HCO3− ions were 80% or more during ACC crystallization, single-phase vaterite was formed.

Preparation of Eu3+ doped SrAl12O19 phosphor (SrAl12O19：Eu3+) using the sol-gel method is described. The effect of the initial Eu/Sr atomic ratio and the reaction temperature on the fluorescence properties of SrAl12O19：Eu3+ was investigated. Powder X-ray diffraction was used to characterize the synthesized products and the optical properties were studied by photoluminescence spectrum. From the obtained phosphor, red luminescence resulting from the 5D0 → 7F2 transition of the Eu3+ ion as the luminescence center was confirmed. The luminescence properties of SrAl12O19：Eu3+ have been investigated by different initial Eu/Sr atomic ratio and optimum atomic ratio of as synthesized phosphors was 0.04. The host crystal synthesized at under 1000℃ was amorphous and at 1100℃ showed crystalline. From the results of EDX, it was confirmed that each element was uniformly dispersed in SrAl12O19：Eu3+. In addition, no change in the proportion of the components in SrAl12O19：Eu3+ due to the rise in the firing temperature was confirmed. The emission intensity of the crystalline SrAl12O19：Eu3+ was lower than that of the amorphous SrAl12O19：Eu3+. This was because the excitation spectrum changed with the crystallization of SrAl12O19. These suggested that crystalline of SrAl12O19 affected for fluorescence properties of the obtained phosphor.

For the future use of hydrogen storage alloys for ammonia synthesis, nitrogen absorption behaviors of ZrVFe, ZrVFe (Ti) and ZrVFe (Ti-Al), where the elements in parentheses were added or substituted, were volumetrically investigated by successively adding nitrogen at selected temperatures between 593 and 653 K. Nitrogen contents of ZrVFe (Ti-Al) were the highest among the tested three alloys and reached 5.4 mass% under 1 MPa of nitrogen at 653 K. Variations of nitrogen contents with nitrogen pressures showed plateau-like features, that is, the nitrogen contents rapidly increased with the pressures maintained at around 0.01 MPa. Only ZrVFe (Ti-Al) showed additional plateau-like features under approximately 0.0001 MPa. Supplementary addition of aluminum brought about nitrogen absorption ability under very low pressures to maximize the nitrogen absorption capacity of ZrVFe (Ti-Al). While X-ray diffraction peaks from ZrVFe and ZrVFe (Ti) did not substantially change on nitrogenation, those from nitrogenated ZrVFe (Ti-Al) shifted to the lower angles, became broad and contained the peaks from separated phases. Supplementary addition of aluminum would impart thorough nitrogen absorption ability to ZrVFe. Absorbed nitrogen would exist on the surfaces or in the vicinity of the surfaces of the alloys, and significant pulverization of ZrVFe (Ti-Al) during proposed activation treatment would provide reactive surfaces to absorb large amounts of nitrogen.

We have found that Cu(NO3)2 and 1,3-dione dioxime afford a variety of multicopper complexes under ambient conditions. Specifically, Cu(NO3)2 and cyclohexane-1,3-dione dioxime gave a trinuclear complex in which the central α-carbons of the three dioxime ligands are oxidized into carbonyl groups, two of which were further reacted with solvent MeOH to give a hemiacetal structure. On the other hand, Cu(NO3)2 and cyclopentane-1,3-dione dioxime gave a dinuclear complex in which Cu(II) was reduced to Cu(I) and two of the three ligands couple to give the fulvalene structure. Together with the previously reported reaction of Cu(NO3)2 and pentane-2,4-dione dioxime into a pentanuclear complex in which the four ligands were changed into trioximes, surprisingly rich chemistry has been discovered for combinations of Cu(NO3)2 and 1,3-dione dioximes.

In this study, we investigated the influence of aluminum precursors on structure and acidic properties of hollow silica–alumina composite spheres, as well as their activity for hydrolytic dehydrogenation of ammonia borane. Hollow silica–alumina composite spheres were prepared via the sol–gel method using polystyrene particles as templates. Activities of the hollow spheres prepared using various aluminum precursors for hydrolytic dehydrogenation of ammonia borane were compared. The molar ratios of evolved hydrogen to ammonia borane introduced were 1.0, 2.8, 1.5, and 3.0 in the presence of the hollow spheres prepared using aluminum ethoxide, aluminum isopropoxide, aluminum tributoxide, and aluminum-tri-sec-butoxide, respectively. Hollow spheres prepared using aluminum precursors with branched alkyl groups exhibit more hydrogen evolution than those prepared using aluminum precursors with normal alkyl groups. From the result of solid-state 27 Al nuclear magnetic resonance spectra and temperature-programmed desorption of ammonia, 4-coordinated aluminum species are related to Bronsted acid sites, and highly dispersed aluminum species increase the number of Bronsted acid sites.

In order to enhance hydrogen storage capacity of carbonaceous materials through metal modification, FeNiCr-carbon composites were prepared by calcination of Fe, Ni and Cr-containing polyacrylonitrile (PAN) fibers fabricated by electrospinning method. Fe (III), Ni (II) and Cr (III) acetylacetonates (M (acac)n) were selected as metal sources. Increase of specific surface area and formation of micropores were observed on heat decomposition of M (acac)n particularly through introduction of steam. Maximal hydrogen content, 1.62 mass%, was obtained at 77 K under 0.8 MPa of hydrogen for a FeNiCr-carbon composite, which contained about 15.5 mass% of metals and had specific surface area of 501 m2 g−1. The hydrogen content exceeded the hydrogen physisorption limit, 2.34 mass% per 1000 m2 g−1, which was calculated on the basis of the commensurate–incommensurate transition with an enhancing factor ρ of 1.126. After hydrogenation at 653 K, no hydrogen desorption peaks were observed for FeNiCr powders derived from M (acac)n, and one peak at 828 K for a carbonaceous sample prepared from unmodified PAN fibers. From the most promising FeNiCr-carbon composite, another peak was recorded at 752 K in addition to the peak at 828 K. The former would be originated from hydrogen on novel sorption sites additionally created on the composite formation.

Calcium carbonate (CaCO3) was synthesized in the CaCl2-Na2CO3-H2O reaction system at the reaction temperature of 40, 50, 60, and 70℃. The initial pH was changed to 2.4–11.0 at 50–70 ℃. The initial pH was adjusted by changing the pH of CaCl2 aqueous solution using HCl and NH3 aqueous solution. The CaCO3 precipitates obtained were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), and specific surface area measurement. In the case of no adding the pH adjustment solution, the product was a mixture of calcite and vaterite at 40 ℃. The formation of aragonite was observed at ≥50 ℃, and single-phase aragonite was obtained at ≥60 ℃, according to XRD measurements. Thus, Aragonite could be synthesized by changing the reaction temperature. At 70 ℃, the synthesis of CaCO3 was performed by changing the initial pH of 2.4–11.0. The formation of single-phase aragonite was detected in the initial pH range of 2.4–10.4. However, a small amount of calcite was contained in aragonite at the initial pH ≥ 10.8. The crystal shape of obtained aragonite was needle-like, and its particle size became finer as the initial pH increased. At an initial pH 2.4, the length and width of the crystals were 2–7 μm and 0.5–1.0 μm, respectively. The finest particles were samples synthesized at the initial pH 11.0, its length and width were 1–2 μm and 0.1–0.2 μm, respectively. The specific surface area of the products was 4.12–14.88 m2 g−1 at the initial pH of 2.4–11.0. The particle size of aragonite could be controlled by changing the initial pH at 70 ℃.

In this study, hollow Co 3 O 4 spheres for the oxidation of carbon monoxide were fabricated using silica templates. The shells were formed by the precipitation of carbonate species on silica templates, and then leached in an aqueous sodium hydroxide solution for the removal of silica templates followed by calcination process. The effects of preparation conditions such as pH (=7–10) and calcination conditions were investigated. Homogeneous hollow Co 3 O 4 spheres were obtained at pH value of 7.09, and high-purity hollow Co 3 O 4 spheres were obtained at calcination temperatures greater than 623 K. The samples calcined at temperatures less than 623 K included cobalt carbonate species, and the carbonate species converted into catalytically inactive cobalt oxyhydroxide after leaching in an aqueous sodium hydroxide solution. The samples calcined at temperatures greater than 623 K included pure Co 3 O 4 phase even after leaching. In the samples calcined at temperatures greater than 623 K, the amount of surface Co 3+ species decreased with calcination temperature, while those of surface Co 2+ species increased with calcination temperature. The activity of the catalyst for the oxidation of carbon monoxide was found to depend on calcination temperature, and the highest activity was obtained over the hollow spheres calcined at 623 K. The results indicate that high purity of Co 3 O 4 phase and the surface Co 3+ species plays an important role for high activity. The hollow spheres also exhibited activity higher than those exhibited by Co 3 O 4 coated on silica templates and Co 3 O 4 nanoparticles, indicating that the hollow spheres are an effective catalyst compared with the supported catalyst and nanoparticle catalyst.

In this paper, we report our investigation into the immobilization of silicomolybdic acid on hollow mesoporous silica spheres and the activity of the modified spheres for hydrolytic dehydrogenation of ammonia borane. Silica shells were coated onto polystyrene (PS) template particles by the sol–gel method, followed by calcination. In this process, a surfactant, cetyltrimethylammonium bromide (CTAB), was added to obtain the mesoporous silica shell. The hollow mesoporous spheres have much greater specific surface area and pore volume than the hollow spheres prepared without CTAB. In addition, the pore sizes of the hollow mesoporous spheres were narrowly distributed and the average was centered at around a diameter of 2–3 nm. The pH was controlled during the immobilization process using amino acids ( l -aspartic acid or l (+)-arginine), and samples were prepared at pH values of 3.0, 7.0, and 9.0. The morphology of silicomolybdic acid immobilized on the hollow mesoporous spheres did not change with changing the pH of the reaction mixtures, but changed the amount of immobilized silicomolybdic acid on the surface of the spheres. Fourier transform infrared spectroscopy (FTIR) spectra of the prepared spheres showed bands originating from silicomolybdic acid. These bands were identified in the samples prepared in solution with pH values = 3.0 and 7.0, however, at pH 9, these characteristic bands were not observed. We found that hydrogen evolution was dependent on the pH of the solution used during their preparation. Indeed, when solutions of NH3BH3 containing the mesoporous samples prepared at pH 3.0, 7.0, and 9.0 were used, volumes of 12.0, 10.0, and 5.0 mL of hydrogen gas were evolved, and were completed after approximately 8, 2, and 2 min, respectively. Also, the molar ratios of evolved hydrogen to the initial NH3BH3 were 2.6, 2.1, and 1.3, respectively. The Mo 3d region of the XPS spectra of the samples was measured after the reaction and these showed that the peak intensities of sample prepared in lower pH had lower intensity than those prepared at higher pH. This indicates that silicomolybdic acid was also immobilized on the inner surface of the hollow mesoporous spheres prepared at lower pH and was highly dispersed. XPS measurements indicate that the valence of the Mo species did not change significantly in the sample prepared at low pH compared to those prepared at higher pH.

Four kinds of ZrVFe alloys with the C14 Laves phase structure had high hydrogen storage capacity under mild pressures, and those alloys would be promising for widespread application such as recovery of hydrogen derived from water splitting. Addition of titanium to ZrVFe lowered hydrogen desorption temperatures through increase of equilibrium pressures. Substitution of ferrovanadium for vanadium did not deteriorate hydrogen occlusion performance of ZrVFe, and provided with lower cost alloys. Another way to reduce the cost would be elimination of purifying step of vanadium prepared by the thermite process, but remaining aluminum proved to bring about lower hydrogen capacity, as evidenced by comparative experiments including a ZrVFe alloy with aluminum intendedly added. Every alloy had fairly good cycling durability except the one contaminated with aluminum.

Hole-transporting materials (HTMs) play a vital role of transporting holes from the perovskite layer to the counter electrode in perovskite solar cells (PSCs). A novel HTM BTPA-8 is feasibly synthesized by incorporating four dimethoxytriphenylamine leaflets and anthracene-based central bridge. BTPA-8 exhibits a suitable band alignment with MAPbI3 (MA = CH3NH3) or FA0.85MA0.15PbI3 (FA=HC(NH2)2), high hole mobility, and high thermal stability. The best FA0.85MA0.15PbI3 device based on BTPA-8 exhibits a power conversion efficiency (PCE) of 17.99% in the reverse scan with an aperture area of 0.09 cm2. Under the same condition, a PCE of 18.92% is achieved by the solar cell based on the standard spiro-OMeTAD (2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene). A comparable PCE of 12.31% is also obtained for BTPA-8 based MAPbI3 device compared with spiro-OMeTAD (13.25%) with an aperture area >1 cm2. BTPA-8 based PSCs exhibit better long-term stability than spiro-OMeTAD due to its high hydrophobicity. A lower synthesis cost of BTPA-8 than that of spiro-OMeTAD along with the elevated long-term stability makes it promising for application in PSCs.

A triphenylamine-based compound containing benzoyl[1,2-b:4,5-b’]dithiophene (BDT) derivative (BTPA-2) has been synthesized and employed in FA0.85MA0.15PbI3 perovskite solar cells (PSCs) as the hole transporting material (HTM). The reference BTPA-1 containing thiophene bridge was also prepared for a comparative study. Compared to the thiophene unit in BTPA-1, the hexyloxy substituted BDT unit in BTPA-2 made the HOMO energy level lower. The more conjugated system with the BDT unit can improve the conductivity and hole mobility. The BTPA-1 and BTPA-2 based FA0.85MA0.15PbI3 PSCs showed the best power conversion efficiencies (PCE) of 12.76 % and 13.97 %, respectively. Larger Voc and higher Jsc for the BTPA-2 based PSC were attributed to its reduced interfacial recombination and more conjugated system compared to the BTPA-1 based PSCs. More hydrophobic property of BTAP-2 made its PSC exhibit better environmental stability than BTPA-1.

Mesoporous hollow spheres have attracted attention because of their high specific surface areas, well-ordered mesopores, and unique void spaces. However, development of effective approaches for synthesis of the mesoporous hollow spheres with an ordered mesopores remains difficult challenge. Herein, we report an approach to synthesize mesoporous silica–zirconia composite hollow spheres via a sol-gel reaction using polystyrene template particles. We found that controlling cetyltrimethylammonium bromide concentration led to a formation of uniform mesopore in silica–zirconia composite shells. In addition, we investigated the effect of the mesoporous hollow spheres in the present study on the hydrolysis of ammonia borane. The hydrolysis reaction was completely finished in the presence of the mesoporous hollow spheres. The mesoporous hollow spheres exhibited a substantially higher amount and rate of hydrogen evolution than the hollow spheres reported in previous studies because of their larger amount of acid sites.

In order to provide with novel composites with high specific surface area for hydrogen storage, FeNiCr-carbon composites were prepared by an alcohol chemical vapor deposition (ACCVD) method with methanol as a carbon source, wherein the abbreviation FeNiCr denoted powdery mixture of hydrogenated Fe, Ni and Cr. After the ACCVD synthesis, the composites were optionally ground to expose inner sorption sites. The peak temperature of hydrogen desorption from as-prepared FeNiCr-carbon composite hydrogenated at 653 K under 1.1 MPa of hydrogen was 723 K, as recorded by temperature programmed desorption (TPD). The peak temperature of hydrogen desorption from ground FeNiCr-carbon composite hydrogenated under the same conditions was as low as 423 K. HD molecules were detected by TPD, after the ground FeNiCr-carbon composite was similarly hydrogenated at 653 K under mixed H2 plus D2 gas. Such was also the case, after the ground composite was hydrogenated at room temperature. It was evidenced that atomic hydrogen took part in hydrogen sorption by the ground composite. The maximum hydrogen concentrations of the FeNiCr-carbon composites were 0.59 mass% and 1.16 mass%, before and after grinding, respectively, at 77 K under 0.77 MPa of hydrogen.

In this work, we investigated influence of Si/Al molar ratio of hollow silica–alumina composite spheres on their activity for hydrolytic dehydrogenation of ammonia borane. The hollow spheres were prepared by polystyrene templates method. In this method, silica–alumina composite shell were coated on polystyrene particles via sol–gel reaction, and the PS template particles were removed by calcination. From the result of transmission electron microscopy, the obtained hollow spheres with Si/Al molar ratios of 12, 23, 49, 92, and 186 were almost similar morphologies. The activities of these hollow spheres for the hydrolytic dehydrogenation of ammonia borane were compared. The amount of hydrogen evolution of hollow spheres with a Si/Al molar ratio of 49 was the highest of all the hollow spheres. From the result of solid-state 27 Al MAS NMR and NH 3 -TPD, the dispersion and amount of aluminum species play important roles in determining the amount of hydrogen evolution. Additionally, the amount of hydrogen evolution depends on the amount of Bronsted acid sites of the hollow spheres.

In this study, we investigated the influence of the preparation conditions of hollow silica–alumina composite spheres on their activity for the hydrolytic dehydrogenation of ammonia borane. Hollow silica–alumina composite spheres were prepared by polystyrene template method, and the polystyrene template particles were removed by calcination. The as-prepared hollow spheres were calcined at 523–873 K for 3 h. From the results of elemental analysis, polystyrene templates were completely removed by calcination at 873 K. small particles around the hollow spheres were observed from the images of transmission electron microscopy. To obtain homogeneous hollow spheres, the as-prepared hollow spheres were calcined at 873 K for 0–12 h. From the results of transmission electron microscopy, homogeneous hollow spheres were obtained by calcination for 0 h. The activity of the hollow spheres was the 2.6 times higher that of the hollow spheres calcined for 3 h. From the results of activity tests and ammonia temperature-programming desorption, the activity of the hollow spheres depends on amount of acid sites.

In this paper, we report fabrication of hollow silica–zirconia composite spheres by polystyrene (PS) template method and control of wall thickness of the hollow spheres in nanoscale. Both the hollow spheres before and after calcination were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), elemental analysis, and powder X-ray diffraction analysis (XRD). Morphology of the hollow spheres does not significantly change after calcination from the results of SEM and TEM images, while the amount of residual PS templates drastically decreases via the calcination procedure from the results of FTIR and elemental analysis. The sample after calcination mainly includes amorphous silica from the results of XRD, indicating that the hollow silica–zirconia composite spheres consist of amorphous phases and/or fine particles. Wall thicknesses of the samples after calcination are controlled by adjusting the amount of PS template suspension, and hollow silica–zirconia composite spheres with the wall thicknesses of 17.5, 15.0, 10.0, and 2.0 nm are obtained using the PS template suspension of 25.0, 33.5, 100.0, and 400.0 g, respectively. The activities of the hollow spheres for hydrolytic dehydrogenation of ammonia borane (NH3BH3) were compared. The evolutions of 2.0, 3.1, 5.0, and 8.0 mL hydrogen from aqueous NH3BH3 solution were finished in about 4, 5, 3, and 7 min in the presence of the hollow spheres with wall thicknesses of 17.5, 15.0, 10.0, and 2.0 nm, respectively. The molar ratios of the hydrolytically generated hydrogen to the initial NH3BH3 in the presence of the hollow spheres with wall thicknesses of 17.5, 15.0, 10.0, and 2.0 nm are 0.5, 0.8, 1.4, and 2.0, respectively. The results indicate that the activity of hollow silica–zirconia composite spheres for hydrolytic dehydrogenation of NH3BH3 improves with decrease of wall thickness of the hollow spheres. From the results of BET adsorption measurements, specific surface area of the hollow spheres increases with decrease of wall thickness of the hollow spheres. The results of activity, specific surface area, and XRD profiles suggest that the primary particles form layer-like structure in the wall of hollow silica–zirconia composite spheres and the number of the layers depends on the wall thickness.

The present work reports influence of preparation conditions of hollow titania–nickel composite spheres on their morphology and catalytic activity for hydrolytic dehydrogenation of ammonia borane (NH 3 BH 3 ). The as-prepared hollow titania–nickel composite spheres were characterized by transmission electron microscopy (TEM). Catalytic activities of the hollow spheres for hydrolytic dehydrogenation of aqueous NaBH 4 /NH 3 BH 3 solution improve with the decrease of Ti + Ni content. From the results of FTIR spectra and elemental analysis, the amount of residual polystyrene (PS) templates is able to be reduced by increasing aging time for the preparation, and the catalytic activity of the hollow spheres increases when the amount of residual PS templates decreases. The carbon content in the hollow spheres prepared with aging time = 24 h is 17.3 wt.%, and the evolution of 62 mL hydrogen is finished in about 22 min in the presence of the hollow spheres from aqueous NaBH 4 /NH 3 BH 3 solution. The molar ratio of the hydrolytically generated hydrogen to the initial NH 3 BH 3 in the presence of the hollow spheres is 2.7.

In this paper, we investigated influence of preparation conditions of hollow silica–nickel composite spheres on their morphology and catalytic activity for hydrolytic dehydrogenation of ammonia borane. In the preparation method of this study, when silica–nickel composite shells were coated on polystyrene templates by the sol–gel method using L(+)-arginine as the promoter for the reaction to form silica–nickel composite shell, the polystyrene templates were dissolved subsequently, even synchronously, in the same medium to form hollow spheres. The as-prepared silica–nickel composite spheres were characterized by transmission electron microscopy and scanning electron microscopy. The effects of Si+Ni content on the morphology were systematically evaluated. All the as-prepared hollow silica–nickel composite spheres have the similar morphology as identified by SEM and TEM measurement. Homogeneity of the hollow silica–nickel composite spheres increases with the increase in the Si+Ni content as shown by the laser diffraction particle size analysis. The catalytic activities of the hollow silica–nickel composite spheres for hydrolytic dehydrogenation of ammonia borane prepared with different Si+Ni contents were compared. The catalytic activity for the hydrogen evolution in the presence of the hollow spheres increases with the increase of Si+Ni content. The results of FTIR spectra of the hollow silica–nickel composite spheres indicate that a certain amount of residual PS templates exists in hollow silica–nickel composite spheres. The residual PS templates was able to be reduced by procedure of as-prepared samples with toluene solvent. The catalytic activity of hollow silica–nickel composite spheres increases with decrease in the amount of residual PS templates.

Objective To present our experience of a novel technique, bladder neck sling suspension technique, in patients undergoing robot-assisted radical prostatectomy (RARP) and evaluate its efficacy for improving early continence outcomes after RARP in comparison with that of the standard technique. Methods Fifty-seven consecutive patients underwent RARP between August 2011 and April 2012. We performed RARP with and without bladder neck sling suspension technique for 27 (sling group) and 30 (nonsling group) patients, respectively, and compared the urinary outcome between the groups. Both subjective and objective assessments of urinary incontinence were performed before and after RARP. Results The International Prostate Symptom Score (P

We describe the synthesis and properties of an orange-red-emitting SrS:Eu2+,Pr3+ phosphor showing a long afterglow of greater than 1000 min under visible light. The SrS:Eu2+,Pr3+ phosphor was synthesized by reduction of SrSO4:Eu3+,Pr3+ formed by liquid phase reaction. The SrS:Eu2+,Pr3+ phosphor showed orange-red emission with a peak wavelength of 611 nm. The excitation band of the phosphor was in the range of visible light above 440 nm. The optimum reaction conditions were achieved under a reducing atmosphere at 1400 °C for 2 h. The optimum quantity of activator was obtained for Eu/Sr and Pr/Sr atomic ratios of 0.00002 and 0.0010, respectively. The afterglow time for the SrS:Eu2+,Pr3+ phosphor after irradiation for 5 min at 1000 lux under a D65 lamp was greater than 1000 min, which was 7 times longer than that obtained with a commercially available CaS afterglow phosphor.

Spherical nickel–silica composite particles were synthesized by sol–gel based method in various solvents followed by in situ activation in aqueous sodium borohydride (NaBH 4 )/ammonia borane (NH 3 BH 3 ) solutions. The resulting products prepared in methyl alcohol, ethyl alcohol, and 2-propyl alcohol include spherical particles with the diameters of 600–800, 200–400 nm, and 200–400 nm, respectively. The evolution of 56, 58, and 62 mL hydrogen was finished in about 50, 90, and 65 min in the presence of the spherical nickel–silica composite particles from aqueous NaBH 4 /NH 3 BH 3 , respectively. Introducing additional aqueous ammonia borane solution to the solution including the in situ synthesized particles, the evolution of 58, 50, and 63 mL hydrogen was finished in about 45, 90, and 45 min, respectively, indicating that all the in situ synthesized particles have the recyclability as the catalysts for hydrolysis of NH 3 BH 3 . The in situ synthesized particles prepared in methyl alcohol and 2-propyl alcohol show higher rate and amount of hydrogen evolution than in situ synthesized particles prepared in ethyl alcohol.

In order to develop novel hydrogen storage materials with high hydrogen capacity, layered compounds with high specific surface areas and large pore volumes, referred to as BN’s, CN’s and C’s, were synthesized from B-, C- and/or N-containing substances through specified wet processing and optimized calcinations. Hydrogen contents at 77 K under 0.8 MPa of hydrogen increased as specific surface areas increased independently of the formulations of the samples, and almost all of them exceeded the predicted values for two dimensional condensation of hydrogen, that is, 2.34 mass% per 1000 m2 g−1. While modification with Pd did not increase the hydrogen capacity, Pt-modification brought about substantially higher hydrogen capacity at 77 K. Ni-modification also imparted higher hydrogen capacity to C’s prepared by calcination of electrospun polyacrylonitrile fibers, but formation of mesopores on destroying micropores through excessive modification would reduce the hydrogen capacity.

Objective To clarify whether spongioplasty decreases the complications rate and the degree of penile curvature in TIP urethroplasty. Methods From 2007 to 2011, 47 patients underwent TIP repair. Thirty-seven underwent spongioplasty, while 10 did not because their bifurcated spongy tissues could be not clearly identified. We investigated whether spongioplasty reduced the incidencerates of complications such as urethrocutaneous fistula. We also evaluated whether spongioplasty contributed to resolving or decreasing penile curvature. In addition, we assessed how many of the patients that underwent spongioplasty did not have to undergo dorsal plication. Results Among the 47 patients who underwent TIP repair, postoperative complications occurred in 3 (8%) of the 37 patients that underwent spongioplasty and 1 (10%) of the 10 who did not. Spongioplasty did not decrease the complications rate of TIP repair. As 15 of the 47 patients demonstrated a straight penis before spongioplasty, the effect of spongioplasty on the correction of penile curvature was analyzed in 32 patients. Dorsal plication was avoided in 19 patients (59%) because their penile curvature had been decreased to within the permissible range ( Conclusion We conclude that spongioplasty can not replace dartos flap coverage of the neourethra after TIP urethroplasty because it did not produce a significant reduction in the complications rate; however, spongioplasty could be used as an additional procedure because it reduced the degree of penile curvature and allowed dorsal plication to be avoided in more than half of the hypospadiac patients that displayed moderately severe curvature.

In this paper, we report a facile and effective approach for fabrication of hollow nickel-silica composite spheres. In this approach, when nickel-silica composite shells were coated on polystyrene templates by the sol–gel method using l (+)-arginine as the promoter for the reaction to form nickel-silica composite shell, the polystyrene templates were dissolved subsequently, even synchronously, in the same medium to form hollow spheres. Neither additional dissolution nor a calcination process was needed to remove the polystyrene templates. The as-prepared nickel-silica composite spheres were characterized by transmission electron microscopy and N 2 adsorption/desorption isotherm analysis. The effects of the amount of l (+)-arginine, the existence of hollow structure, and the kinds of promoter for sol–gel reaction on the morphology, porosity and mean pore size, and specific surface areas were systematically evaluated. The catalytic activity of the hollow nickel-silica composite spheres for hydrolytic dehydrogenation of ammonia borane was compared to that of the hollow nickel-silica composite spheres prepared with aqueous ammonia solution and nickel-silica composite spheres without hollow structure. The catalytic activity for the hydrogen evolution over the hollow spheres was higher than those of the hollow spheres prepared with aqueous ammonia solution and the nickel-silica composite spheres without hollow structure. Moreover, the results of diffuse reflectance UV–vis spectra indicate that the amount of hydrogen evolution was correlated with the reduction degree of nickel species after hydrolytic dehydrogenation of ammonia borane.

In this paper, we report an effective approach to the fabrication of hollow titania–nickel composite spheres, hollow zirconia–nickel composite spheres, and hollow silica–nickel composite spheres. In this approach, metal oxide–nickel composite shells were coated on polystyrene particles by the sol–gel method and the polystyrene templates were dissolved subsequently, or even synchronously, in the same medium to form hollow spheres. Neither additional dissolution nor a calcination process was needed to remove the polystyrene templates. The as-prepared hollow metal oxide–nickel composite spheres were characterized by transmission electron microscopy. The catalytic activities of hollow titania–nickel composite spheres, hollow zirconia–nickel composite spheres, and hollow silica–nickel composite spheres for hydrolytic dehydrogenation of aqueous NaBH 4 /NH 3 BH 3 solution were compared. The evolutions of 64, 58, and 18 mL hydrogen were finished in about 49, 69, and 162 min in the presence of the hollow titania–nickel composite spheres, hollow zirconia–nickel composite spheres, and hollow silica–nickel composite spheres from aqueous NaBH 4 /NH 3 BH 3 solution, respectively. The molar ratios of the hydrolytically generated hydrogen to the initial NH 3 BH 3 both in the presence of hollow titania–nickel composite spheres, hollow zirconia–nickel composite spheres, and hollow silica–nickel composite spheres are 2.8, 2.4, and 0.1 (the theoretical value of 3.0), respectively, indicating that the hollow titania–nickel composite spheres and hollow zirconia–nickel composite spheres show much higher hydrogen evolution rates and the amount of hydrogen evolution via hydrolytic dehydrogenation of ammonia borane than the hollow silica–nickel composite spheres. From the results of ATR-IR spectra, a certain amount of residual PS templates exists in hollow silica–nickel composite spheres, and the amount of the residual PS templates were able to be reduced by increasing the amount of aqueous ammonia solution used for the preparation. The catalytic activity of hollow silica–nickel composite spheres increases when the amount of residual PS templates decreases.

Ce 3+ , Tb 3+ codoped amorphous calcium silicate phosphor was prepared by heating (830 °C for 30 min) Ce 3+ , Tb 3+ codoped calcium silicate hydrate phosphor formed by liquid-phase reaction. The excitation peak wavelength of the resulting phosphor was 330 nm and the emission peak wavelengths were at 544 nm, attributed to the 5 D 4 → 7 F 5 transition of Tb 3+ , and at 430–470 mm, attributed to Ce 3+ . The intensity ratio of the two peaks could be freely controlled by varying the Tb/Ca atomic ratio of the Ce 3+ , Tb 3+ codoped amorphous calcium silicate phosphor, allowing light to be emitted over a wide range from blue to green. It was clarified that energy transfer exists from Ce 3+ to Tb 3+ .

Amorphous nickel catalysts were synthesized by reducing the nickel(II) species in an aqueous NaBH 4 /NH 3 BH 3 solution with and without l -arginine. The nickel catalyst with l -arginine maintains relatively high activity for hydrolysis of NH 3 BH 3 to generate a stoichiometric amount of hydrogen with the cycle number up to 11 (827 mL s −1 (mol-Ni) −1 at the 11th cycle with l -arginine = 35 mg), while the reaction rate in the presence of the bare nickel catalyst was relatively low through the cycle number up to 11 (232 mL s −1 (mol-Ni) −1 at the 11th cycle). After catalytic reaction, the nickel catalyst with l -arginine possesses the high dispersion (diameters of nickel nanoparticles l -arginine maintains the dispersion of nickel nanoparticles (diameters of nickel nanoparticles

Laparoendoscopic single-site surgery (LESS), a minimally invasive procedure, is gaining widespread acknowledgment in pediatric urology. We report the case of a 7-year-old girl with Turner's syndrome with 45,XO/46,XY mosaicism, for whom bilateral prophylactic gonadectomy using LESS was performed. Histopathological findings revealed bilateral streak gonads. The surgical and cosmetic outcome was excellent. Diagnostic and therapeutic laparoscopy is essential for accurate clinical management of patients with disorders of sex development. Although this is only a single case report, it supports the theory that LESS is an exceedingly practical and superior technique for such children, since it provides excellent magnification, as well as allowing normal psychological development owing to the concealed scar. Further studies and long-term follow-up are required to evaluate the benefits and limitations of applying LESS in pediatrics.

We report the case of a newborn infant with cloacal exstrophy. On the 16th day after birth, complete primary exstrophy repair was performed. The bladder tissue obtained during surgery contained collagen tissue and a little smooth muscle, as well as a few neuron cells and kit-positive interstitial cells in the submucosal layer. This is the first report of a histopathologic analysis of the bladder tissue in cloacal exstrophy. We also discuss the influence of the pathologic changes on bladder dysfunction.

This study reports the synthesis of novel red-emitting Eu 3+ -activated amorphous alkaline earth silicate phosphors with high emission intensities. Eu 3+ -activated barium (strontium) silicate hydrate phosphors were synthesized using a liquid phase reaction and then heated at 850 °C for 0.5 h to form amorphous barium (strontium) silicate phosphors. These amorphous phosphors emitted in the red region following near-UV (395 nm) irradiation. The internal quantum efficiencies of the Eu 3+ -activated amorphous barium silicate phosphor and strontium silicate phosphor were 56% and 60%, respectively, even though these phosphors were in the amorphous state.

Hypospadias is one of the most common congenital disorders in males. Impaired fetal androgen action interferes with masculinization, including external genitalia formation, and can result in this anomaly; however, the molecular etiology remains unknown. Recent molecular approaches, including gene-targeting approaches in mice and single nucleotide polymorphisms analyses in humans, might provide an opportunity to identify the causative and risk factors of this anomaly. Several genes, such as sonic hedgehog, fibroblast growth factors, bone morphogenetic proteins, homeobox genes, and the Wnt family regulate external genitalia formation. Mastermind-like domain containing 1/chromosome X open reading frame 6 mutation and activating transcription factor 3 variants have been shown to be associated with the incidence of isolated hypospadias. In addition, this anomaly may be associated with a specific haplotype of the gene for estrogen receptor alpha, which mediates the estrogenic effects of environmental endocrine disruptors, and the effects of these disruptors on external genitalia formation might depend on individual genetic susceptibility. These molecular studies will refine our knowledge of the genetic mechanism involved in external genitalia formation, and lead to new strategies for the clinical management of hypospadias.

Nephrogenic rests are nodular collections of undifferentiated renal blastema cells in the postnatal kidney that are recognized as putative precursor lesions of Wilms tumor. In this study, we report the case of a 3-year-old boy who was diagnosed with a hyperplastic intralobar nephrogenic rest extending through the renal pelvis and ureter. After radical nephrectomy, adjuvant chemotherapy was performed as done in stage II Wilms tumor. We also investigated the mutation of the WT1 gene and identified a related single-nucleotide polymorphism (rs16754). We consider that not only various genetic mutations but also single-nucleotide polymorphisms or other epigenetic factors might be involved in the development of Wilms tumor.

Purpose We investigated the long-term physical, hormonal, and sexual outcomes of males with disorders of sex development (DSD) and discussed the necessity of long-term follow-up for these patients after surgery. Patients and Method Twelve DSD patients (average age, 21.0 ± 3.6 years old) who had been designated as male in childhood (3 ovotesticular DSD, four 45,XO/46,XY mixed gonadal dysgenesis, four 46,XX testicular DSD, and one 46,XY DSD; androgen insensitivity syndrome) were enrolled. For these patients, height, penile length, and testicular volume were evaluated in adulthood. Serum levels of luteinizing hormone, follicle-stimulating hormone, and testosterone were also measured during follow-up. In addition, sexual function and romantic relationships were evaluated. Results Development of the penis and testes was poor. According to the hormonal study, these patients were diagnosed with hypergonadotropic hypogonadism or normogonadism; 90% patients had experienced penile erection and masturbation at the time of participation, and 70% and 40% patients had experienced ejaculation and sexual intercourse with female partners, respectively. No patients preferred to avoid sexual contact with women. Conclusion Although DSD males had an undeveloped penis and testis and had hypergonadotropic hypogonadism or normogonadism, most had male sexual potential and male sex identity as long as testicular tissues were preserved.

The emission intensity of phosphors is often subject to concentration quenching after doping of the activator in the host crystal rises above a certain limit. This study describes the preparation of novel phosphors based on tobermorite that do not exhibit concentration quenching. In the preparation of phosphors, Eu 3+ ions are exchanged with intercalated Ca 2+ ions within the tobermorite by dipping in EuCl 3 solution. The emission intensity of the Eu 3+ doped tobermorite increased with increasing Eu/Ca atomic ratio and attained a maximum value of 8.6% for a Eu/Ca atomic ratio of 0.22. Heating of the phosphor at 800 °C resulted in a three-fold improvement in emission intensity.

This paper reports on the effect of the amount of Li + and Sr 2+ ions added to a red-emitting phosphor (CaS:Eu 2+ , Pr 3+ ) on afterglow time upon visible-light irradiation. The afterglow time of CaS:Eu 2+ , Pr 3+ phosphor with Sr 2+ ions (initial Sr/Ca atomic ratio of 0.10) was longer than that of the phosphor without Sr 2+ ions by 20 min. Moreover, the afterglow time of the Ca 0.9 Sr 0.1 S:Eu 2+ , Pr 3+ phosphor with Li + ions increased with an increase in the initial Li/Ca atomic ratio and was 146 min for an initial Li/Ca atomic ratio of 0.04. The lattice strain of the phosphor with both Sr 2+ and Li + ions showed a minimum value for this synthetic condition. The trap depths resulting from Li + ion addition increased by about 0.145 eV. By adding both Li + and Sr 2+ ions to the CaS:Eu 2+ , Pr 3+ host, it was possible to improve the afterglow time.

Objective To investigate the risk of germ-line transmission of vector sequences after in vivo adenovirus-mediated gene transfer to mouse testes and to discuss whether an adenovirus vector could be used in the future to treat male factor infertility. Design Experimental animal study. Setting Laboratory research setting in the Department of Nephro-urology at Nagoya City University Graduate School of Medical Sciences in Japan. Animal(s) Eight-week-old B6C3F1 mice. Intervention(s) Adenovirus vector carrying a LacZ transgene as a marker was injected into the interstitial space (intratesticular injection) or seminiferous tubules (intratubular injection) of the mouse testis. Main Outcome Measure(s) An assessment by polymerase chain reaction (PCR) and histological analyses of the proportion of adenovirus vectors administered into the testis that can infect epididymal sperm and transmit to fetuses derived from these males 3, 7, 14, 28, and 35 days after intratesticular or intratubular adenovirus injection. Result(s) No PCR signal was identified in genomic DNA extracted from the epididymal sperm of all mice on each day after intratesticular or intratubular adenovirus injection. On reverse transcriptase (RT)-PCR analysis of mRNA isolated from fetuses derived from these males on each day after intratesticular or intratubular adenovirus injection, no fetuses had amplified products, although about 30% of the fetuses generated by microinjection into fertilized eggs had LacZ transcripts. On histochemical staining, no two-cell and 12.5 d.p.c. fetuses showed β-gal activity. These sperm and fetus studies showed that adenovirus-mediated gene transfer to the testis does not cause infection of or transmission to the germ line or fetuses. Conclusion(s) The risk of germ-line transmission after adenovirus-mediated gene transfer to the testis is extremely low, and this method can be exploited in the future for the treatment of male factor infertility.

This paper reports on the afterglow mechanism and thermoluminescence (TL) of a red-emitting CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion upon irradiation by visible light (D65 lamp). In the TL glow curve of the CaS:Eu2+,Pr3+ phosphor, a TL peak was observed near 120 °C. The luminescence center of the CaS:Eu2+,Pr3+ phosphor was the Eu2+ ion and the trap depth of the CaS:Eu2+,Pr3+ phosphor with the cation vacancy (Trap 1) which formed by incorporation of the Pr3+ ion was 0.202 eV. A cation vacancy (Trap 2) was formed by incorporation of the Li+ ion in the CaS:Eu2+,Pr3+ phosphor. In the TL glow curve of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion, two TL peaks were observed near 120 and 200 °C. The TL luminance of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion increased with an increase in the initial Li/Ca atomic ratio. The two TL peaks moved to the high-temperature side with an increase in heating rate. The cation vacancy (Trap 2) calculated from the Hoogenstraaten method was 0.118 eV. The afterglow time of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion was prolonged by generation of a shallow trap.

This paper reports the synthesis of large plate-like gypsum (calcium sulfate) dihydrate generated from waste gypsum board via a wet process. Gypsum hemihydrate was formed by dehydrating waste gypsum board in a sodium sulfate solution at 100 °C for 1 h to form needle-like crystals. The large gypsum dihydrate was formed by lowering the temperature of the gypsum hemihydrate suspension below 80 °C. The large plate-like gypsum dihydrate was obtained by adding seed crystals to a suspension cooled at 80 °C. When 40 μm seed crystals were added at 0.5 mass%, the large plate-like gypsum dihydrate crystals obtained from waste gypsum board had average dimensions of 250 μm length × 100 μm width × 35 μm thickness.

This paper reports the effect of lithium ion addition on the afterglow time of green-emitting Ce 3+ and Pr 3+ codoped CaS phosphor by black light irradiation. CaS:Ce 3+ , Pr 3+ , irradiated with black light, emitted in the green region and showed afterglow. The afterglow time of CaS:Ce 3+ , Pr 3+ was relatively short (about 10 min). When a Li + invades the free space in a CaS crystal lattice, new cation vacancy is formed for the charge compensation in the Ca 2+ site. The afterglow intensity of CaS:Ce 3+ , Pr 3+ , with Li + incorporated in the host, increased to three times that of the original sample (CaS:Ce 3+ , Pr 3+ ). The afterglow time of CaS:Ce 3+ , Pr 3+ , with Li + incorporated was extended to 40 min.

Objectives To study the effect of testicular biopsy in childhood on spermatogenesis, fertility, and paternity in subsequent adulthood using an animal model. Considerable controversy exists as to whether testicular biopsy should be performed in children. Methods Four-week-old male ICR mice were subjected to unilateral testicular biopsy (group 1), bilateral biopsy (group 2), or a sham operation (group 3). At 8 weeks of age, the testicular weight, seminiferous tubular diameter, and manifestation of apoptosis were examined. The motility of sperm obtained from the epididymides of the same testes was also examined. Fertility and paternity was assessed in each mouse by housing it with 2 age-matched females for 2 weeks. Results No significant differences were found in the testicular weight, mean seminiferous tubular diameter, or number of apoptotic germ cells between the biopsied and unbiopsied side in group 1 or between groups 2 and 3. No significant differences were noted in the average sperm motility rate between the biopsied (30.5% ± 14.5%) and unbiopsied side (35.8% ± 19.2%) in group 1, or between groups 2 (37.6% ± 18.0%) and 3 (39.3% ± 10.0%). All females who coupled with the male mice in all groups became pregnant. The average number of offspring from the 2 female mice was not significantly different among the three groups (group 1, 13.1 ± 2.3; group 2, 12.3 ± 2.0; and group 3, 11.3 ± 3.0). Conclusions The spermatogenesis, fertility, and paternity of mature mice were unaffected by testicular biopsy in childhood.

Recent maintenance technology and typical deformation cases of Japanese railway tunnels are presented in this paper. Inspection of tunnel lining is divided into primary inspection and secondary inspection. New technology of non-destructive inspection which is in the process of practicable inspection to make this automatic is introduced. Repair and reinforce methods of deformation tunnels are divided into: (a) countermeasures against earth pressure; (b) countermeasures for deteriorate lining; (c) countermeasures against leakage of water and frost damage; and (d) countermeasures against spalling. Moreover, three cases concerning recent typical deformation of Japanese railway tunnels are shown; one of them is the Tukayama tunnel concerning countermeasures against plastic earth pressure and the others are the Fukuoka tunnel and the Rebunhama tunnel concerning an accident caused by spalling of tunnel lining.

A 23-month-old boy presented with an 11-month history of abdominal distention. Examination disclosed a large tumor in the right kidney and transabdominal radical nephrectomy was performed. Histopathological study demonstrated clear cell sarcoma of the kidney (CCSK). Cytogenetic analyses performed with blood lymphocytes showed translocation (1;6) (p32.3;q21). This is the first case of CCSK showing chromosomal translocation in blood lymphocytes. In addition, molecular analyses demonstrated high expression levels of EGFR and KIT proteins in the tumor tissue of CCSK. These molecular findings suggest that tyrosine kinase receptors may be potential therapeutic targets for CCSK in the future.

Objectives. To evaluate the practical application and limitation of ultrasonography and retrograde urethrography in detecting prostatic utricle associated with hypospadias. Methods. Between 1995 and 1999, 80 patients with hypospadias, 1 month to 16 years of age (mean age 3 years, 6 months), underwent ultrasonography and retrograde urethrography to detect the prostatic utricle. Results. Of the 80 patients examined, the prostatic utricle was found in a total of 36 patients (45.0%) by ultrasonography and/or retrograde urethrography. Ultrasonography revealed the prostatic utricle in 27 (75%) of the 36 patients; in 6 of the 27, it was not detected by retrograde urethrography. Retrograde urethrography revealed the prostatic utricle in 30 (83%) of the 36 patients; in 9 of the 30, it was not visualized by ultrasonography. Retrograde urethrography was slightly more sensitive in detecting the prostatic utricle than was ultrasonography. In the remaining 44 patients, the prostatic utricle was not detected by either examination method. Conclusions. Although retrograde urethrography is considered the most useful method for detecting any degree of the prostatic utricle, we recommend routine ultrasonography because it is noninvasive, painless, and simple.

An 11-year-old boy with episodes of intermittent gross hematuria and recurrent left flank pain was referred to our institute with left ureteropelvic junction (UPJ) obstruction. (99m)Tc diethylenetriamine pentaacetic acid (DTPA) renography revealed an obstructive pattern in the left kidney, and the existence of a crossing vessel at the UPJ was suspected with excretory urography. Laparoscopic surgery was performed, and intraoperatively no aberrant vessels were found. Upon opening the ureter, a solitary round polyp was found. The segment of the UPJ area containing the polyp was completely removed, followed by laparoscopic dismembered pyeloplasty. Pathologic findings demonstrated a benign fibroepithelial polyp.