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31.
Reena Amatya Shrestha Thuy Duong Pham Mika Sillanpää 《Journal of Applied Electrochemistry》2010,40(7):1407-1413
The polycyclic aromatic hydrocarbons (PAHs) with high molecular mass are renown for their high persistence in the soil, hydrophobic
and toxicity. Remediation of these pollutants is still an unsolved task and needs more researches to be performed. The coupling
of electrokinetics (EK) with ultrasonic energy (US) has advantages on desorbing and migrating PAHs from contaminated soil.
US and EK work together to destroy PAHs. The objective of this study was to treat PAHs contaminated soil by using EK and ultrasonication.
The contaminated oil contained about 100 mg kg−1 chrysene. Experiments with US, EK and combined EK and ultrasound were conducted in reactors and pans with and without iron
anodes. Results indicated that the removal was more effective with lower concentrations of chrysene. The average removal was
better in experiment with combined EK and ultrasound using iron anode. This might be due to increase in electroconductivity
by iron ions. 相似文献
32.
Mari Kallioinen Mika Mänttäri Jutta Nuortila-Jokinen Timo Sutela 《Desalination》2010,250(3):1002-1004
The total effluent load of a paper mill can be significantly decreased by recycling of purified clear filtrate (CF) back to paper-making process. The CF treated with membranes can be reused, for instance, as wire section shower water and in the dilution of chemicals. The main requirements for a membrane in CF treatment are high filtration capacity, high retention of turbidity and low fouling tendency. Previous studies have shown that the regenerated cellulose (RC) ultrafiltration (UF) membrane C30F (current trade name UC030T) is especially suitable for the treatment of paper mill process waters. Every paper-making process is, however, different. Thus, filtration experiments are required in order to find the most optimal membrane for the treatment of a certain process water. In this study the best membrane for the treatment of acidic clear filtrate (ACF) was searched. The performance of the C30F membrane was compared with five UF and three microfiltration (MF) membranes. The results revealed that in addition to the C30F membrane, also some other membranes produced high filtration capacity with ACF (approximately 200 L/(m2h bar)). All the tested membranes also retained over 90% of turbidity. The extremely hydrophilic C30F membrane had, however, lower fouling tendency compared to the other tested membranes. Therefore, it was concluded that the C30F membranes were the best possible membrane for the ACF treatment. 相似文献
33.
Hagren V von Lode P Syrjälä A Korpimäki T Tuomola M Kauko O Nurmi J 《International journal of food microbiology》2008,125(2):158-161
We describe a system consisting of rapid sample enrichment and homogeneous end-point PCR analysis that enables the detection of Salmonella in various food matrices in 8 h. Sample preparation starts with 6 h enrichment step in supplemented broth, after which Salmonella cells are collected with immunomagnetic particles. The particles are washed and dispensed to ready-to-use PCR reaction vessels, which contain dried assay-specific reagents and an internal amplification control. PCR is performed with a novel instrument platform utilising the sensitive label technology of time-resolved fluorometry. Qualitative assay results are automatically interpreted and available in 45 min after sample addition. The overall accuracy, sensitivity and specificity of the Magda CA Salmonella system were 99.1%, 98.4% and 100.0%, respectively, based on the evaluation of 107 samples (beef, pork, poultry and ready-to-eat meals) artificially contaminated with sub-lethally injured Salmonella cells. 相似文献
34.
35.
Yasuo Kagawa Mami Hiraoka Yukiko Miyashita-Hatano Madoka Shishido-Oki Mamiko Yoshida Susumu Kondou Mika Sugiura Kazumi Sawakami-Kobayashi Masaaki Takahashi Hideji Tajima Masafumi Yohda 《Journal of Bioscience and Bioengineering》2010,110(4):505-508
A low-cost and simple on-site technique for genotyping single nucleotide polymorphisms (SNPs) was developed. The technique is based on allele-specific primer PCR and the recently developed bead arrays in a single tip technique. The performance of the method was verified by genotyping four SNPs that correlate with cardiovascular diseases. 相似文献
36.
Sueyoshi et al. (2009) have examined a synergy effect between electricity and gas services in the US electric utility industry. They have compared electricity-specialized firms with diversified utility firms in their financial performance and corporate value. A problem of their study is that it has not empirically measured the operational performance of the electric utility firms. As an extension of the preceding study, this research investigates the operational performance of 104 US electric utility firms (1990–2004) by fully utilizing DEA (Data Envelopment Analysis). This study finds the three new policy implications. First, the synergy effect has not existed in the operational performance of diversified utility firms before and after the deregulation on the US electricity markets. Thus, core business concentration is more effective for electric utility firms than corporate diversification to enhance their operational performance under the current US deregulation policy. Second, the operational performance has had an increasing trend until 1996 and a decreasing trend after 1996. Thus, the US deregulation policy has been influential on their operational performance. Third, the enhancement in operational performance of electric utility firms has improved their financial performance. The improvement in financial performance has increased their corporate value. Thus, this study finds the business causality among operational performance, financial performance and corporate value in the US electric utility industry. 相似文献
37.
38.
Hirahara Y Kimura M Inoue T Uchikawa S Otani S Hirose H Suzuki S Uchida Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(5):225-231
The applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to screening for 140 pesticides in agricultural products was examined. Validation of multi-residue screening methods for the determination of 88 pesticides in 12 crops (asparagus, cauliflower, burdock, carrot, broccoli, spinach, matsutake mushroom, orange, soybean, sesame, millet and tea) was done by GC and GC/MS. Of the 88 pesticides, 63 were obtained with recoveries in the range from 50 to 150% at the 0.1 microg/g level in the 12 crops. Applicability of the official methods in Japan to 74 pesticides, including 22 pesticides with low recovery (< 50%) by GC or GC/MS analysis, was also examined by LC/MS/MS. LC/MS/MS acquisition parameters were established for 67 pesticides in positive and negative electrospray ionization (ESI) modes. Of 67 pesticides validated in 7 crops using LC/MS/MS at the 0.1 microg/g level, 44 showed recoveries in the range from 50 to 150%. The occurrence of matrix interference in LC/MS/MS can lead to false-positive detection of MCPA in spinach, cabbage and orange and false-negative detection of four pesticides in orange, spinach, apple and unpolished rice. Good linearity was observed in the studied ranges by GC, GC/MS (r > 0.990) and LC/MS/MS (r > 0.995). Of the total of 140 pesticides validated by GC, GC/MS and LC/MS/MS, 107 were newly recognized as suitable subjects for screening. 相似文献
39.
Hirahara Y Kimura M Inoue T Uchikawa S Otani S Hirose H Suzuki S Uchida Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(5):213-221
A screening method is described for determining 200 pesticides, except dimethipin, divided into four groups by means of gas chromatography/tandem mass spectrometry (GC/MS/MS) using an ion trap mass spectrometer equipped with automated gain control (AGC). The quantitation limit for 194 pesticides was 0.01 mg/kg on a crop basis, except for allidochlor, dimethoate, hexythiazox, methamidophos and triadimenol. The calibration curve of each pesticide was linear in the range of 0.04-5.0 microg/mL. One hundred and ninety-nine pesticides were added to matrix of potato, spinach, cabbage, apple, orange, soybean and unpolished rice at twice the limits of quantitation. The recoveries of 194 pesticides from all crops were satisfactory (50-150%) for screening purposes. Although some pesticides in apple and orange were not determined by selected ion monitoring (SIM) analysis at the limits of quantitation, all of them were identified by ion-trap GC/MS/MS at the same concentration. Thus, the ion trap GC/MS/MS technique is useful for the screening of residual pesticides present at low levels in agricultural products. 相似文献
40.
What Types of Defects Are Really Discovered in Code Reviews? 总被引:1,自引:0,他引:1
M ntyl Mika V. Lassenius Casper 《IEEE transactions on pattern analysis and machine intelligence》2009,35(3):430-448
Research on code reviews has often focused on defect counts instead of defect types, which offers an imperfect view of code review benefits. In this paper, we classified the defects of nine industrial (C/C++) and 23 student (Java) code reviews, detecting 388 and 371 defects, respectively. First, we discovered that 75 percent of defects found during the review do not affect the visible functionality of the software. Instead, these defects improved software evolvability by making it easier to understand and modify. Second, we created a defect classification consisting of functional and evolvability defects. The evolvability defect classification is based on the defect types found in this study, but, for the functional defects, we studied and compared existing functional defect classifications. The classification can be useful for assigning code review roles, creating checklists, assessing software evolvability, and building software engineering tools. We conclude that, in addition to functional defects, code reviews find many evolvability defects and, thus, offer additional benefits over execution-based quality assurance methods that cannot detect evolvability defects. We suggest that code reviews may be most valuable for software products with long life cycles as the value of discovering evolvability defects in them is greater than for short life cycle systems. 相似文献