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931.
Cordova-Rosa SM Dams RI Cordova-Rosa EV Radetski MR Corrêa AX Radetski CM 《Journal of hazardous materials》2009,164(1):61-66
Time-course performance of a phenol-degrading indigenous bacterial consortium, and of Acinetobacter calcoaceticus var. anitratus, isolated from an industrial coal wastewater treatment plant was evaluated. This bacterial consortium was able to survive in the presence of phenol concentrations as high as 1200mgL(-1) and the consortium was more fast in degrading phenol than a pure culture of the A. calcoaceticus strain. In a batch system, 86% of phenol biodegradation occurred in around 30h at pH 6.0, while at pH 3.0, 95.2% of phenol biodegradation occurred in 8h. A high phenol biodegradation (above 95%) by the mixed culture in a bioreactor was obtained in both continuous and batch systems, but when test was carried out in coke gasification wastewater, no biodegradation was observed after 10 days at pH 9-11 for both pure strain or the isolated consortium. An activated sludge with the same bacterial consortium characterized above was mixed with a textile sludge-contaminated soil with a phenol concentration of 19.48mgkg(-1). After 20 days of bioaugmentation, the remanescent phenol concentration of the sludge-soil matrix was 1.13mgkg(-1). 相似文献
932.
Tatiana A.R. Silva Lucas F. Ferreira Letícia M. Souza Luiz R. Goulart João M. Madurro Ana G. Brito-Madurro 《Materials science & engineering. C, Materials for biological applications》2009,29(2):539-545
Immobilization and hybridization of oligonucleotides or specific-gene PCR product (DENV-1), a conserved genomic sequence of the dengue virus, onto graphite electrode modified with poly(4-hydroxyphenylacetic acid), were carried out with success using both direct electrochemical oxidation of guanine or redox electroactive indicator ethidium bromide.Studies of oligonucleotides hybridization with the complementary target showed a decrease of both guanosine and adenosine current peaks, when compared with the peak previously obtained before the hybridization. Immobilized ssDNA, DENV-1, was hybridized with various concentrations of target DNA. The interaction between DENV-1 hybridized onto the modified graphite electrodes surface and the intercalator, ethidium bromide, was observed by differential pulse voltammetry, monitoring the current change generated to the DNA intercalator accumulated onto the modified electrode after DNA hybridization. For the determination of complementary target, the proposed method exhibited a good dynamic range (12–42 nmol L? 1) and a low detection limit (7.12 nmol L? 1).AFM images showed that the oligonucleotides or single-stranded DNA, DENV-1, before hybridization, had roughness values lower than the double stranded obtained after hybridization.The new surface obtained in these work, as well as the possibility of utilization of the same to monitor hybridization events is a promising strategy for the development of DNA electrochemical biosensors. 相似文献
933.
Fractional wavelet transform 总被引:2,自引:0,他引:2
The wavelet transform, which has had a growing importance in signal and image processing, has been generalized by association with both the wavelet transform and the fractional Fourier transform. Possible implementations of the new transformation are in image compression, image transmission, transient signal processing, etc. Computer simulations demonstrate the abilities of the novel transform. Optical implementation of this transform is briefly discussed. 相似文献
934.
On the fatigue behaviour of quenched and tempered at 300 and 600 °C SAE 1045 steel in an environment of sugar cane juice
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J. Muñoz Cubillos S.A. Rodríguez J.J. Coronado 《Fatigue & Fracture of Engineering Materials & Structures》2016,39(10):1299-1308
SAE 1045 steel is widely used for manufacturing shafts in the sugar cane mills of the sugar industry. These shafts are designed with an expectation of a long lifetime. However, fatigue failures occur frequently. The sugar cane juice processed in these mills has corrosive properties that can alter the fatigue life of these shafts. In this research, the fatigue strength of SAE 1045 steel between 1 × 104 and 2 × 105 cycles in air and in sugar cane juice, with two different microstructures (tempered martensite at 300 °C and tempered martensite at 600 °C), was determined in rotating bending. The microstructure of the materials was characterized using optical microscopy, and the fracture surfaces were characterized using scanning electron microscopy. The results show that the fatigue strength at 2 × 105 cycles for the tempered condition at 600 °C decreases 7% because of the sugar cane juice effect, and for the tempered condition at 300 °C, the fatigue strength decreases 15%. 相似文献
935.
Enhanced Solar‐to‐Hydrogen Generation with Broadband Epsilon‐Near‐Zero Nanostructured Photocatalysts
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Yi Tian Francisco Pelayo García de Arquer Cao‐Thang Dinh Gael Favraud Marcella Bonifazi Jun Li Min Liu Xixiang Zhang Xueli Zheng Md. Golam Kibria Sjoerd Hoogland David Sinton Edward H. Sargent Andrea Fratalocchi 《Advanced materials (Deerfield Beach, Fla.)》2017,29(27)
The direct conversion of solar energy into fuels or feedstock is an attractive approach to address increasing demand of renewable energy sources. Photocatalytic systems relying on the direct photoexcitation of metals have been explored to this end, a strategy that exploits the decay of plasmonic resonances into hot carriers. An efficient hot carrier generation and collection requires, ideally, their generation to be enclosed within few tens of nanometers at the metal interface, but it is challenging to achieve this across the broadband solar spectrum. Here the authors demonstrate a new photocatalyst for hydrogen evolution based on metal epsilon‐near‐zero metamaterials. The authors have designed these to achieve broadband strong light confinement at the metal interface across the entire solar spectrum. Using electron energy loss spectroscopy, the authors prove that hot carriers are generated in a broadband fashion within 10 nm in this system. The resulting photocatalyst achieves a hydrogen production rate of 9.5 µmol h?1 cm?2 that exceeds, by a factor of 3.2, that of the best previously reported plasmonic‐based photocatalysts for the dissociation of H2 with 50 h stable operation. 相似文献
936.
本系统采用TI公司的单片机MSP430F2274作为系统的控制核心,由A/D数据采集、功能转换、量程自动转换以及键盘显示等模块组成。被测信号经过功能转换电路,转换成与其成比例关系的电压,再经12位AD574转换送单片机进行数据处理,结合继电器完成量程的自动转换,从而通过由MC14433组成的数字电压表头实时反映测试参数,同时本系统还具有相对误差测量、自动休眠等功能。通过实验测试,该系统满足设计要求,具有量程自动转换,具有精度高、工作稳定、交互界面友好等特色。 相似文献
937.
Felipe Espinosa Elena López Raúl Mateos Manuel Mazo Ricardo García 《Autonomous Robots》2001,11(2):137-148
This paper presents the theoretical support and experimental results of the application of advanced and intelligent control techniques to the drive control and trajectory tracking systems on a robotic wheelchair. The adaptive optimal control of the differential drive helps to improve the automatic guidance system's safety and comfort taking into consideration operating conditions such as load and distribution changes or motion actuator limitations. Furthermore, the incorporation of an optimal controller to minimize location errors and a fuzzy controller to adapt the linear velocity to the characteristics of the trajectory, provide the vehicle with a high degree of intelligence and autonomy, even when faced with obstacles. The global control solution implemented increases the features of the wheelchair for handicapped people, especially for those with a high degree of disability. 相似文献
938.
939.
Manuel Moreno-Valladares Veronica Moncho-Amor Iraide Bernal-Simon Eaut Agirre-Iturrioz María lvarez-Satta Ander Matheu 《International journal of molecular sciences》2022,23(15)
We present a case report on an older woman with unspecific symptoms and predominant long-term gastrointestinal disturbances, acute overall health deterioration with loss of autonomy for daily activities, and cognitive impairment. Autopsy revealed the presence of alpha-synuclein deposits spread into intestinal mucosa lesions, enteric plexuses, pelvic and retroperitoneal nerves and ganglia, and other organs as well as Lewy pathology in the central nervous system (CNS). Moreover, we isolated norovirus from the patient, indicating active infection in the colon and detected colocalization of norovirus and alpha-synuclein in different regions of the patient’s brain. In view of this, we report a concomitant norovirus infection with synthesis of alpha-synuclein in the gastrointestinal mucosa and Lewy pathology in the CNS, which might support Braak’s hypothesis about the pathogenic mechanisms underlying synucleinopathies. 相似文献
940.
Carlos Garcia-Padilla Estefanía Lozano-Velasco María del Mar Muoz-Gallardo Juan Manuel Castillo-Casas Sheila Cao-Carrillo Francisco Jos Martínez-Amaro Virginio García-Lpez Amelia Arnega Diego Franco Virginio García-Martínez Carmen Lpez-Snchez 《International journal of molecular sciences》2022,23(15)
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma. 相似文献