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971.
The decay and termite resistance and effects of a robust leaching process on the efficacy of zinc borate-incorporated particleboard were examined. Particleboards (300 × 300 × 15 mm) prepared from particles of mixed wood species generated from demolished construction materials were incorporated with zinc borate at target retentions of 0%, 1%, 1.5% and 2% of the particle weight. An in-line treatment method was utilized to introduce the powdered chemical during the blending stage. ICP analysis indicated that the amount of zinc borate was not lost during manufacturing. Standard static bending tests demonstrated that there was no significant loss in mechanical properties. The decay and termite tests indicated that the efficacy of zinc borate at a higher retention was enough to suppress the biological activity, even after application of a robust leaching process.  相似文献   
972.
Dehydrogenation of organic chemical hydrides has been investigated with catalysts in which the economical Ni was adopted as catalytic component and SiO2 as support. In this work dehydrogenation of methylcyclohexane was performed as organic chemical hydride in a fixed-bed catalytic reactor in the temperature range of 653–713 K, having 5, 10, 15, and 20 wt.% Ni content.  相似文献   
973.
Enrofloxacin is a synthetic second‐generation fluoroquinolone used as an antimicrobial agent exclusively in veterinary medicine. To simulate the treatment of wastewater contaminated by enrofloxacin, four‐day long fed‐batch runs were carried out according to the Fenton process with an enrofloxacin solution as model, to which hydrogen peroxide and ferrous ion were added twice a day. The residual enrofloxacin concentration was practically coincident to that detected at the end of the batch tests. Hydrogen peroxide was almost completely consumed after each feeding period, while the total organic carbon (TOC) concentration decreased gradually within three days, corresponding to a reduction > 58 %. From the third day on, the TOC falling rate was quite low. A yellow sludge settled due to the precipitation of both Fe(OH)3 and a complex formed by ferric ion with adsorbed enrofloxacin and/or its oxidation products.  相似文献   
974.
975.
976.
A new polycyclic aromatic hydrocarbon (PAH)-degrading Gram-negative bacterium Aeromonas salmonicida subsp. achromogenes strain NY4 was isolated from coking wastewater sludge. Strain NY4 could not grow on1-hydroxy-2-naphthoic acid, hexadecane or hexanol as sole carbon source but phenanthrene. This strain was able to utilize several known microbial metabolites of PAHs, including catechol, protocatechuic acid, salicylic acid, and phenol as sole carbon source. The mixture of the acidic and neutral fraction, acidic fraction alone and neutral fraction alone of phenanthrene metabolites were prepared and analyzed by GC-MS. A total of at least 27 metabolites were identified as the degradation products of phenanthrene by strain NY4. Among them, 1-hydroxy-α-oxo-2-naphthaleneacetic acid, 2-hydroxy-α-oxo-1-naphthaleneacetic acid, 2-hydroxy-1-(1-hydroxy-2-naphthalenyl)-ethanone, 1,2-dihydro naphtha [2,1-b] furan-2-ol and 2,3-dihydro naphtha [1,2-b] furan-2-ol have not been reported as the metabolites of phenanthrenes so far. The accumulation patterns of phenanthrene metabolite accumulation by strain NY4 depended on the incubation time, inoculum size and concentration of phenanthrene. Based on the degradation metabolites of phenanthrene by strain NY4, degradation pathways are proposed. This is the first report of PAH degradation in Aeromonas salmonicida, which lay the foundation for recognition and further characterization of PAH degradation metabolites and pathways in Aeromonas salmonicida strains.  相似文献   
977.
液压泵退化特征提取是实现故障预测的关键环节。在液压泵性能退化过程中,其振动信号复杂度高、非线性强,难以有效地提取退化特征,为此,本文提出一种基于敏感分量融合的退化特征提取方法。采用改进局部特征尺度分解(ILCD)方法对振动信号进行分解,并利用贝叶斯信息准则与所构建的敏感因子,对内禀尺度分量进行筛选,以减少干扰分量的影响,得到敏感分量,有效抓取特征信息;在此基础上,引入离散余弦变换代替传统复合谱分析中的傅里叶变换,提出离散余弦变换-复合谱(DCS)算法,以解决信息遗漏问题,并利用DCS对敏感分量进行融合,提取复合谱熵作为退化特征,以提高对退化过程的表征能力;最后,通过对液压泵性能退化试验实测振动信号的应用分析,验证了该方法的有效性。  相似文献   
978.
陈世豪 《中国氯碱》2014,(12):36-38
介绍一种有机固体为活化剂生产复合型发泡剂ADC产品方法,分析了复合型发泡剂ADC产品的生产技术,产品的发气量及分解温度与产品中活化剂成份比例关系等因素。  相似文献   
979.
Conventional and inverted organic solar cells of poly[9,9‐dioctyl‐fluorene‐co‐bithiophene] (F8T2) as liquid‐crystal semiconducting polymer and fullerene as electron acceptor were fabricated and characterized. An effect of thermal treatment of the films on annealing condition near glass transition was investigated for tuning optimization and improving the photovoltaic and optical properties. Annealing treatment below the glass transition improved the photovoltaic performance and carrier diffusion in crystal growth of active layer. The X‐ray diffraction patterns indicate a crystalline structure with molecular order of F8T2 in crystal index, 100 as a layer distance between sheets of F8T2 chains. The photovoltaic properties were based on molecular interactions with molecular ordering in active layer at crystal state. As the photovoltaic mechanisms, the F8T2 thin film as p‐type semiconducting polymer worked for electron‐donor layer to support light‐induced generation, carrier diffusion and charge transfer near interface in active layer. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
980.
Plasma water treatment technology, which aims to produce strong oxidizing reactive particles that act on the gas–liquid interface by way of discharging, is used to treat the organic pollutants that do not degrade easily in water. This paper presents a diffuse-discharge plasma water treatment method, which is realized by constructing a conical air gap through an uneven medium layer. The proposed method uses water as one electrode, and a dielectric barrier discharge electrode is constructed by using an uneven dielectric. The electric field distribution in the discharge space will be uneven, wherein the long gap electric field will have a smaller intensity, while the short one will have a larger intensity. A diffuse glow discharge is formed in the cavity. With this type of plasma water treatment equipment, a methyl orange solution with a concentration of 10 mg l-1 was treated, and the removal rate was found to reach 88.96%.  相似文献   
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