Beijing University of Technology

About: Beijing University of Technology is a education organization based out in Beijing, Beijing, China. It is known for research contribution in the topics: Microstructure & Laser. The organization has 31929 authors who have published 31987 publications receiving 352112 citations. The organization is also known as: Běijīng Gōngyè Dàxué & Beijing Polytechnic University.

A Near Infrared Light Triggered Hydrogenated Black TiO2 for Cancer Photothermal Therapy

Abstract: White TiO2 nanoparticles (NPs) have been widely used for cancer photodynamic therapy based on their ultraviolet light-triggered properties. To date, biomedical applications using white TiO2 NPs have been limited, since ultraviolet light is a well-known mutagen and shallow penetration. This work is the first report about hydrogenated black TiO2 (H-TiO2 ) NPs with near infrared absorption explored as photothermal agent for cancer photothermal therapy to circumvent the obstacle of ultraviolet light excitation. Here, it is shown that photothermal effect of H-TiO2 NPs can be attributed to their dramatically enhanced nonradiative recombination. After polyethylene glycol (PEG) coating, H-TiO2 -PEG NPs exhibit high photothermal conversion efficiency of 40.8%, and stable size distribution in serum solution. The toxicity and cancer therapy effect of H-TiO2 -PEG NPs are relative systemically evaluated in vitro and in vivo. The findings herein demonstrate that infrared-irradiated H-TiO2 -PEG NPs exhibit low toxicity, high efficiency as a photothermal agent for cancer therapy, and are promising for further biomedical applications.

Nitrogen removal via nitrite from municipal wastewater at low temperatures using real-time control to optimize nitrifying communities.

Abstract: Although many studies regarding nitrogen removal via nitrite have been carried out, very limited research has been undertaken on nitrogen removal via nitrite at low temperatures. In this study, to improve the nitrogen removal efficiency from municipal wastewater, a pilot-plant of sequencing batch reactor with a working volume of 54 m3 was used to investigate nitrogen removal via nitrite from municipal wastewater at normal and low water temperature. The obtained results showed that high nitrogen removal efficiency with effluent total nitrogen below 3 mg/L could be achieved. Using real-time control with temperature ranging from 11.9 to 26.5 degrees C under normal dissolved oxygen condition (> or =2.5 mg/L), nitrogen removal via nitrite was successfully and stably achieved for a long period (180 days) with average nitrite accumulation rate above 95%. Fluorescence in situ hybridization was carried out to investigate the quantitative changes of nitrifying microbial community in the activated sludge. Fluorescence in situ hybridization results approved that the nitrifying microbial communities were optimized; ammonia oxidizing bacteria became the dominant nitrifying bacteria and nitrite oxidizing bacteria had been washed out of the activated sludge.

Visual saliency detection by spatially weighted dissimilarity

Abstract: In this paper, a new visual saliency detection method is proposed based on the spatially weighted dissimilarity. We measured the saliency by integrating three elements as follows: the dissimilarities between image patches, which were evaluated in the reduced dimensional space, the spatial distance between image patches and the central bias. The dissimilarities were inversely weighted based on the corresponding spatial distance. A weighting mechanism, indicating a bias for human fixations to the center of the image, was employed. The principal component analysis (PCA) was the dimension reducing method used in our system. We extracted the principal components (PCs) by sampling the patches from the current image. Our method was compared with four saliency detection approaches using three image datasets. Experimental results show that our method outperforms current state-of-the-art methods on predicting human fixations.

Seismoionospheric GPS total electron content anomalies observed before the 12 May 2008 Mw7.9 Wenchuan earthquake

Abstract: [1] The global ionospheric map (GIM) is used to observe variations in the total electron content (TEC) of the global positioning system (GPS) associated with 35 M ≥ 6.0 earthquakes that occurred in China during the 10-year period of 1 May 1998 to 30 April 2008. The statistical result indicates that the GPS TEC above the epicenter often pronouncedly decreases on day 3–5 before 17 M ≥ 6.3 earthquakes. The GPS TEC of the GIM and electron density profiles probed by six microsatellites of FORMOSAT3/COSMIC (F3/C) are further employed to simultaneously observe seismoionospheric anomalies during an Mw7.9 earthquake near Wenchuan, China, on 12 May 2008. It is found that GPS TEC above the forthcoming epicenter anomalously decreases in the afternoon period of day 6–4 and in the late evening period of day 3 before the earthquake, but enhances in the afternoon of day 3 before the earthquake. The spatial distributions of the anomalous and extreme reductions and enhancements indicate that the earthquake preparation area is about 1650 km and 2850 km from the epicenter in the latitudinal and longitudinal directions, respectively. The F3/C results further show that the ionospheric F2 peak electron density, NmF2, and height, hmF2, significantly decreases approximately 40% and descends about 50–80 km, respectively, when the GPS TEC anomalously reduces.

An efficient two-party quantum private comparison protocol with decoy photons and two-photon entanglement

Abstract: Following some ideas of the quantum secret sharing (QSS) protocol (2008, Phys. Lett. A 372, 1957), we propose an efficient quantum private comparison (QPC) protocol for comparing information of equality with the help of a third party (TP). The protocol can ensure fairness, efficiency and security. The protocol is fair, which means that one party knows the sound result of the comparison if and only if the other one knows the result. The protocol is efficient with the help of the TP for calculating. However, the TP cannot learn any information about the players' respective private inputs and even about the comparison result and cannot collude with any player. The protocol is secure for the two players, that is, any information about their respective secret inputs will not leak except the final computation result. A precise proof of security of the protocol is presented. Applications of this protocol may include private bidding and auctions, secret ballot elections, commercial business, identification in a number of scenarios and so on.