Measurements of N2O and CH4 from the aerated composting of food waste

Emissions of N2O and CH4 from an aerated composting system were investigated using small-scale simulated reactors. The results show relatively high emissions of N2O at the beginning of composting, in proportion to the application amount of food waste. After 2 days, the N2O emission decreased to 0.53 ppmv on average, near to the background level in the atmosphere (0.45 ppmv). The addition of composted cattle manure increased N2O emissions not only at the beginning of composting, but also during the later period and resulted in two peak emission curves. Good correlation was observed between the N2O concentration at the air outlet and NO2- concentration in waste, suggesting a generation pathway for N2O from NO2- to N2O. Methane was only detected in treatments containing composted cattle manure. The high emission of methane illustrates the involvement of anoxic/anaerobic microorganisms with the addition of composted manure. The result suggests the existence of anoxic or anaerobic microsite inside the waste particles even though ventilation was employed during the composting process.     

Significance of attached cyanobacteria relevant to the occurrence of musty odor in Lake Kasumigaura

The microorganisms and compounds causing musty odor in the second largest lake in Japan, Lake Kasumigaura, where the water is used for drinking, fisheries and agricultural purposes, were examined during the severe occurrence of musty odor in 1989 and 1990. This study was undertaken to determine the microorganisms and their metabolites responsible for the musty odor. Phormidium tenue, which has been reported to be the main contributor of the odor in Lake Kasumigaura, was isolated. Furthermore, four monoxenic strains of the odor producing attached cyanobacteria, Phormidium viscosum, Lyngbya allorgei, Oscillatoria splendida and Phormidium uncinatum, were isolated from submerged rocks and sediments in the lake. All of the four attached strains produced only geosmin, which was confirmed by gas chromatograph/mass spectrometer analysis, in the monoxenic cultures. In particular, we confirmed for the first time that P. viscosum, L. allorgei and P. uncinatum produced geosmin. Both the planktonic Phormidium tenue, a well known 2-methylisoborneol (MIB) producer and geosmin-producing attached cyanobacteria were closely associated with the occurrence of musty odor in Lake Kasumigaura.     

Recovery oriented phosphorus adsorption process in decentralized advanced Johkasou

Decentralized advanced wastewater treatment using adsorption and desorption process for recovery and recycling oriented phosphorus removal was developed. Adsorbent particles made of zirconium were set in a column, and it was installed as subsequent stage of BOD and nitrogen removal type Johkasou, a household domestic wastewater treatment facility. The water quality of the effluent of adsorption column in a number of experimental sites was monitored. The effluent phosphorus concentration was kept below 1 mg l(-1) during 90 days at all the sites. Furthermore, over 80% of the sites achieved 1 mg l(-1) of T-P during 200 days. This adsorbent was durable, and deterioration of the particles was not observed over a long duration. The adsorbent collected from each site was immersed in alkali solution to desorb phosphorus. Then the adsorbent was reactivated by soaking in acid solution. The reactivated adsorbent was reused and showed almost the same phosphorus adsorption capacity as a new one. Meanwhile, the desorbed phosphorus was recovered with high purity as trisodium phosphate by crystallization. It is proposed as a new decentralized system for recycling phosphorus that paves the way to high-purity recovery of finite phosphorus.     

Security of Practical Time-Reversed EPR Quantum Key Distribution

Abstract. We propose a proof of the security of a time-reversed EPR quantum key distribution protocol against enemies with unlimited computational power. The considered protocol uses interactive key distillation, and the proof holds for implementations using imperfect photon sources.     

Precoded Transmit Path Diversity in FS-OFDM on UWB Channels

In impulse-radio or DS/SS UWB communications, a prerake scheme has been proposed to achieve path diversity while reducing computational complexity in a mobile terminal. On the other hand, in an OFDM system, fractional sampling (FS) has been proposed to achieve path diversity with a single antenna. However, in the FS-OFDM system, it is necessary to oversample a received signal that leads to larger power consumption in the terminal side. In this paper, a precoded transmit path diversity scheme in an OFDM system has been proposed. The proposed scheme can achieve path diversity without oversampling the received signal.     

Influence of timing jitter on quadrature charge sampling

The influence of timing jitter on quadrature charge sampling for a direct conversion receiver has been evaluated. In contrast to voltage sampling, the charge sampling mixer integrates the signal current instead of tracking the signal voltage. The charge sampling mixer has been applied to RF direct sampling in wireless receivers. The influence of timing jitter on charge sampling has been analysed in some literatures. However, in wireless receivers, quadrature sampling is required in order to demodulate I-phase and Q-phase signals. Different from charge sampling, timing jitter causes crosstalk between these signals. The influence of timing jitter on quadrature sampling is investigated.     

Beam Current Monitor with a High-Tc Current Sensor and SQUID at the RIBF

It is widely recognized that non-destructive measurement at high resolution of the DC current of high-energy heavy-ion beams is important. Therefore, a high critical temperature (HTc) superconducting quantum interference device (SQUID) beam current monitor has been developed for use in the radioactive isotope beam factory (RIBF) at RIKEN in Japan. Unlike at other existing facilities, a low-vibration, pulse-tube refrigerator cools the HTc fabrications including the SQUID in such a way that the size of the system is reduced and the running costs are lowered. As a result, using a prototype of the HTc SQUID monitor, the intensity of a 1 μA Xe beam (50 MeV/u) was successfully measured with 100 nA resolution. Furthermore, since a higher resolution is necessary, development of an improved HTc current sensor with two coils has begun. A spraying machine was developed to fabricate the new HTc current sensor by dip-coating a thin layer of Bi₂–Sr₂–Ca₂–Cu₃–O _x (Bi-2223) onto a 99.6 % MgO ceramic substrate. Results from a new HTc current sensor produced using this machine are reported here.     

Optimal surface chemistry for peptide immobilization in on-chip phosphorylation analysis

We investigated the optimal surface chemistry of peptide immobilization for on-chip phosphorylation analysis. In our previous study, we used a heterobifunctional cross-linker sulfosuccinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxalate (SSMCC) to immobilize cysteine-terminated peptides on an amine-modified gold surface. The study revealed that the phosphorylation efficiency and rate were low (only 20% at 2 h) comparing with the reaction in solution. In this study, to improve the phosphorylation efficiency, the kinase substrates were immobilized via poly(ethylene glycol) (PEG), a flexible, hydrophilic polymer. An improvement in cSrc phosphorylation was achieved (60% at 1 h) from using a PEG-inserted peptide and SSMCC. However, no phosphorylation could be detected when the peptide was immobilized with a PEG-containing cross-linker. Fluorescence-labeled peptide studies revealed that the use of longer cross-linkers resulted in lower immobilization density. We considered that the flexible PEG linker was preferable to secure high phosphorylation efficiency for the immobilized peptide, probably due to the improvement of cSrc accessibility and peptide mobility, but the immobilization protocol is critical for keeping high density of the peptide immobilization. In addition, such an accelerating effect of PEG linker against on-chip phosphorylation of an immobilized peptide may depend on kinase structures or the position of the active center, because no improvement of on-chip peptide phosphorylation was observed in protein kinase A. However, PEG linker also did not suppress the phosphorylation in protein kinase A. Thus, we concluded that SSMCC and PEGylated peptide will be a good combination for the surface chemistry of on-chip phosphorylation in peptide array.     

Highly Efficient Water Oxidation Photoanode Made of Surface Modified LaTiO2N Particles

An improved variation of highly active/durable O₂‐evolving LaTiO₂N powder‐based photoelectrode has been fabricated by pre‐cleaning the powder with mild polysulfonic acid and by homogeneous deposition of CoO_x co‐catalyst aided by microwave annealing. The treatment in aqueous solution of poly(4‐styrene sulfonic acid) results in removal of surface LaTiO₂N layers, forming fine pores in the crystallites. The CoO_x co‐catalyst by microwave deposition in Co(NH₃)₆Cl₃/ethylene glycol homogeneously covers the particle surface. The LaTiO₂N powder is fabricated into particle‐transferred electrodes on Ti thin film supported on solid substrate. The modified LaTiO₂N grains on the electrode serve as a highly active O₂‐evolving photoanode achieving 8.9 mA cm^?2 of the photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) in 0.1 m NaOH (pH 13) under solar‐simulator irradiation Airmass 1.5 Global (AM 1.5G). The activity has been much improved, compared with conventional LaTiO₂N treated in mineral acid or with CoO_x deposited by impregnation. The new electrode also exhibits better durability in fixed‐potential chronoamperometric tests under AM 1.5G irradiation.     

Advances in characterization of triacylglycerols: Expansion of materials used in Joint JOCS/AOCS Official Method Ch 3a-19

Joint JOCS/AOCS Official Method Ch 3a-19 was an improvement over triacylglycerol characterization methods based on hydrolysis with pancreatic lipase. In this study we developed three further improvements and applied them to the analysis of the fatty acid distribution in triacylglycerols from trout. First, the liquid–liquid extraction of lipid by chloroform and methanol from fish meat was replaced with a single extraction step using pre-packed columns. This allowed the extraction time to be reduced from 30 min/sample to 5 min/sample with ca. 10% higher yield using half the volume of the extraction solvent, chloroform. Both extraction methods gave similar FA composition of the extracted oil. Furthermore, an alternative CALB lipase and an alternative normal-phase solid phase extraction column were shown to reliably duplicate the results obtained with the Official Method Ch 3a-19. In addition, the SPE columns could be used at least 5 times without loss of separation and without carryover.