高性能混凝土抗盐蚀耐久性试验研究

设计4组不同掺量浮石和沸石的高性能混凝土,每组各制作12个试件,其中3个试件用饱和石灰水浸泡2年,3个试件用MgSO4溶液浸泡2年,3个试件用NaCl溶液浸泡2年,然后对它们进行冻融试验,研究高性能混凝土经不同盐溶液侵蚀后质量和抗压强度的变化规律,分析不同矿物掺合料的掺加对高性能混凝土抗盐蚀耐久性的影响。试验结果表明:MgSO4溶液对高性能混凝土的侵蚀破坏能力大于NaCl溶液,掺加浮石和沸石的高性能混凝土抗盐蚀耐久性较强,且沸石掺量越高,抗盐蚀耐久性越强。     

NR5A1 is required for functional maturation of Sertoli cells during postnatal development

The orphan nuclear receptor steroidogenic factor 1 (NR5A1 (SF-1)) is expressed in both Sertoli and Leydig cells in the testes. This study investigates the postnatal development of the testes of a gonad-specific Nr5a1 knockout (KO) mouse, in which Nr5a1 was specifically inactivated. The KO testes appeared histologically normal from postnatal day 0 (P0) until P7. However, disorganized germ cells, vacuoles, and giant cells appeared by P14 in the seminiferous tubules of KO but not control mice. Expression of NR5A1 and various factors was examined by immunohistochemistry (IHC). The number of NR5A1-positive Sertoli cells in the KO testes was lower compared with controls at all the developmental stages and decreased to nearly undetectable levels by P21. IHC for anti-Müllerian hormone and p27, immature and mature Sertoli cell markers, respectively, indicated a delay in Sertoli cell maturation in the KO testes. The number of Sertoli cell-expressing factors involved in Sertoli cell differentiation including WT1, SOX9, GATA4, and androgen receptor were lower in the KO testes compared with controls. Furthermore, fewer proliferating cell nuclear antigen-positive proliferative germ cells were observed, and the number of TUNEL-labeled cells was significantly higher in the KO testes compared with controls at P14 and P21, indicating impaired spermatogenesis. IHC for CYP11A1 (SCC) indicated the presence of steroidogenic Leydig cells in the interstitium of the KO testes at all stages examined. These results suggest that NR5A1 is essential for Sertoli cell maturation and therefore spermatogenesis, during postnatal testis development.     

New type of pressurized cultivation method providing oxygen for piezotolerant yeast

For efficient oxygen supply to pressurized culture, we developed a method using a highly pressurized membrane reactor with an air-saturated medium circulation system. The new method increased the cell growth of aerobic yeast approximately 20 folds larger than that in the case of using a conventional method.     

Display of the human (pro)renin receptor on Bombyx mori nucleopolyhedrovirus (BmNPV) particles using Bm cells

The human (pro)renin receptor (hPRR) was displayed on the surface of Bombyx mori nucleopolyhedrovirus (BmNPV) with and without fusion to glycoprotein 64 (GP64) of the BmNPV. hPRR1 is a native hPRR with an additional FLAG peptide sequence inserted between the signal peptide and prorenin-binding domain. hPRR2 has the prorenin-binding domain inserted between amino acid residues (81)Asp and (82)Pro of GP64. hPRR4 has the prorenin-binding domain inserted in (81)Asp and (320)Met of partially deleted GP64. Incorporation of hPRR was confirmed in recombinant BmNPV (rBmNPV) but not in cysteine protease-deleted rBmNPV. hPRR1 was observed in ER, but hPRR2 and hPRR4 were observed around the endoplasmic reticulum (ER) and in its periphery. rBmNPV-hPRR1 and -hPRR2, carrying hPRR1 and hPRR2 respectively, showed binding affinity to human renin, but rBmNPV-hPRR4 did not. The presence of hPRR4 of rBmNPV-hPRR4 was confirmed in western blotting under nonreducing conditions, suggesting that although hPRR4 was incorporated in rBmNPV-hPRR4, it behaved as a non-functional aggregate. This rBmNPV display system can also be used for analyzing a ligand-receptor interaction.     

纺织品水萃取液甲醛含量的测定

按照GB/T2912.1-1998《纺织品甲醛的测定第一部分游离水解的甲醛(水萃取法)》测定纺织品、服装上游离甲醛的含量时,为减少数据的离散性,提高测试结果的正确程度,详细讨论了测试过程中所用水质、试剂、溶液的配制与标定、试样的准备、仪器的校正及有效数字的保留等对测定结果的影响。     

Bactericidal effects of konjac fluid on several food-poisoning bacteria

In this study, the bactericidal effects of Japanese alkaline foods on food-poisoning bacteria were evaluated. Konjac is an alkaline food soaked in calcinated calcium (the pH of konjac fluid ranges from 11.42 to 12.53). Konjac fluids completely inactivated Escherichia coli, enterohemorrhagic E. coli O157:H7 and E. coil O26:H9, Salmonella Enteritidis, Vibrio parahemolyticus. and Staphylococcus aureus. The initial level of 6 log CFU/ml dramatically decreased after incubation with konjac fluid, and no viable gram-negative bacterium cells could be detected within 1 to 2 days and no viable S. aureus cells could be detected within 3 to 5 days. On the other hand, treatment with konjac fluid was also effective in reducing levels of spore-forming bacteria (Bacillus subtilis, Bacillus cereus, Clostridium perfringens, and Clostridium botulinum type E and type A). At least a 4-log reduction of spore-forming bacteria was obtained in konjac fluid within 7 to 14 days. Vegetative cells were more susceptible to konjac fluid than spores were. When the initial cell count was 6 log CFU/ml, a few surviving spores remained for 60 to 90 days, but no spores could be detected after 120 days. When the initial count of spore-forming bacteria was 3 to 4 log CFU/ml, the cells considered vegetative were completely inactivated within I to 3 days. Repeated treatment with konjac fluid caused complete inactivation of spores in less than 1 to 3 days. Our studies indicate that konjac fluid, which has a long history of use in food, will control food-poisoning bacterial contamination during the production or preservation of konjac and other foods and has a preventive effect on bacteria that can cause severe disease at uniquely low levels.     

Atmospheric outflow of anthropogenic semivolatile organic compounds from East Asia in spring 2004

To estimate the emissions of anthropogenic semivolatile organic compounds (SOCs) from East Asia and to identify unique SOC molecular markers in Asian air masses, high-volume air samples were collected on the island of Okinawa, Japan between 22 March and 2 May 2004. Contributions from different source regions (China, Japan, the Koreas, Russia, and ocean/local) were estimated by use of source region impact factors (SRIFs). Elevated concentrations of hexachlorobenzene (HCB), hexachlorcyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), and particulate-phase polycyclic aromatic hydrocarbons (PAHs) were attributed to air masses from China. A large proportion of the variation in the current-use pesticides, gas-phase PAHs, and polychlorinated biphenyl (PCB) concentrations was explained by meteorology. Chlordanes showed a technical mixture profile and similar concentrations regardless of source region. alpha/gamma HCH and trans/cis chlordane ratios did not vary significantly with different source regions and had regional averages of 2.5 +/- 1.0 and 1.2 +/- 0.3, respectively. Particulate-phase PAH concentrations were significantly correlated (p value < 0.05) with other incomplete combustion byproduct concentrations, including elemental mercury (Hg0), CO, NOx, black carbon, submicrometer aerosols, and SO2. By use of measured PAH, CO, and black carbon concentrations and estimated CO and black carbon emission inventories, the emission of six carcinogenic particulate-phase PAHs was estimated to be 1518-4179 metric tons/year for Asia and 778-1728 metric tons/year for China, respectively. These results confirm that East Asian outflow contains significant emissions of carcinogenic particulate-phase PAHs.     

Grating-coupled surface plasmon enhanced short-circuit current in organic thin-film photovoltaic cells

In this study, we demonstrate the fabrication of grating-coupled surface plasmon resonance (SPR) enhanced organic thin-film photovoltaic cells and their improved photocurrent properties. The cell consists of a grating substrate/silver/P3HT:PCBM/PEDOT:PSS structure. Blu-ray disk recordable substrates are used as the diffraction grating substrates on which silver films are deposited by vacuum evaporation. P3HT:PCBM films are spin-coated on silver/grating substrates. Low conductivity PEDOT:PSS/PDADMAC layer-by-layer ultrathin films deposited on P3HT:PCBM films act as the hole transport layer, whereas high conductivity PEDOT:PSS films deposited by spin-coating act as the anode. SPR excitations are observed in the fabricated cells upon irradiation with white light. Up to a 2-fold increase in the short-circuit photocurrent is observed when the surface plasmon (SP) is excited on the silver gratings as compared to that without SP excitation. The finite-difference time-domain simulation indicates that the electric field in the P3HT:PCBM layer can be increased using the grating-coupled SP technique.     

Fabrication of fluorescence tunable electrospun conjugated polycarbazole fibers containing gold nanoparticles

In this report, we demonstrate a novel way to tune the fluorescence property of electrospun conjugated polymer fibers. The basic strategy is to use a soluble precursor polymer with gold nanoparticles for electrospinning, which is then cross-linked by applying potential cycles in an electrochemical cell. Electroactive carbazole units in electrospun precursor polymer fibers were converted to conjugated polymer fibers. Since the conjugated polymer fibers can be formed, the fluorescence from the conjugated polymer fibers can be tuned by the rate of the conversion and doping of the fibers. Furthermore, the quenching of the fluorescence, which overlaps with the plasmon band of the gold nanoparticles, was observed. The quenching of the fluorescence properties of the fibers was dependent on the amount of gold nanoparticles inside the fibers.     

Low-temperature fabrication of bunch-shaped ZnO nanowires using a sodium hydroxide aqueous solution

Bunch-shaped ZnO nanowires film was successfully fabricated by the forced-hydrolysis-initiated-nucleation of anhydrous zinc acetate in an aqueous solution of zinc acetate and sodium hydroxide at low temperature. X-ray diffraction and a field emission scanning electron microscope clarified their formation mechanism and morphology development. The morphology was controllable by adjusting the solution temperature and deposition time. ZnO nanowires obtained at 65 degrees C for 6 h have a high aspect ratio of about 106. The smaller diameter with higher aspect ratio of ZnO nanowires, the easier the formation of bunch shapes by the capillary force during the drying process. This fabrication technique indicated that bunched ZnO film was prepared at low cost, and fittable to low heat-resistance substrates such as a polymer substarte.