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71.
The polydopamine (PDA) coating α-S hydrophilic composites (SD) were fabricated by a self-assembly process for enhanced α-S photocatalytic performance under visible light. The XRD patterns analysis indicated that we had successfully prepared the orthorhombic α-S. The SEM, FT-IR and TGA showed that PDA had been successfully coated on α-S. The photocatalytic ability was illustrated by the DRS and FL. Moreover, the measurement of the water contact angle of SD and the corresponding original α-S (SA) showed the hydrophilicity of α-S had been improved. The photocatalytic ability of SD and SA was evaluated by photocatalytic decomposition of Methylene blue (MB) solution. The MB elimination rate with SD in the photocatalytic process was 2.46 times as great as that with SA under visible light. The enhanced photocatalytic ability could be attributed to the improved hydrophilicty of α-S. 相似文献
72.
Zhuo Yudong Cai Wenlong Zhu Daoqian Zhang Hongchao Du Ao Cao Kaihua Yin Jialiang Huang Yan Shi Kewen Zhao Weisheng 《中国科学:物理学 力学 天文学(英文版)》2022,65(10):1-8
Science China Physics, Mechanics & Astronomy - The exact properties of dark matter remain largely unknown despite the accumulating evidence. If dark matter is composed of weakly interacting... 相似文献
73.
Lyu Jiahui Sun Guoji Zhu Liyan Ma Hongchao Ma Chun Dong Xiaoli Fu Yinghuan 《Journal of Solid State Electrochemistry》2020,24(2):375-387
Journal of Solid State Electrochemistry - Herein, a novel Ti/black TiO2-PbO2 micro/nanostructured photoanode with tunable hydrophobic/hydrophilic characteristics was fabricated via the facile... 相似文献
74.
Li Wenfeng Lyu Jiahui Zhou Kun Ma Hongchao Ma Chun Dong Xiaoli Fu Yinghuan 《Journal of Solid State Electrochemistry》2020,24(7):1577-1585
Journal of Solid State Electrochemistry - Reasonable hydrophobic anode is deemed to be a promising electrode for photoelectrocatalytic degradation of wastewater. In this study, the C3N4-modified... 相似文献
75.
Adaptive Two-Point Stepsize Gradient Algorithm 总被引:7,自引:0,他引:7
Combined with the nonmonotone line search, the two-point stepsize gradient method has successfully been applied for large-scale unconstrained optimization. However, the numerical performances of the algorithm heavily depend on M, one of the parameters in the nonmonotone line search, even for ill-conditioned problems. This paper proposes an adaptive nonmonotone line search. The two-point stepsize gradient method is shown to be globally convergent with this adaptive nonmonotone line search. Numerical results show that the adaptive nonmonotone line search is specially suitable for the two-point stepsize gradient method. 相似文献
76.
Yuchen Hao Prof. Xiaoli Dong Prof. Shangru Zhai Prof. Hongchao Ma Xiuying Wang Prof. Xiufang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18722-18728
Sunlight‐driven dinitrogen fixation can lead to a novel concept for the production of ammonia under mild conditions. However, the efficient artificial photosynthesis of ammonia from ordinary air (instead of high pure N2) has never been implemented. Here, we report for the first time the intrinsic catalytic activity of Bi2MoO6 catalyst for direct ammonia synthesis under light irradiation. The edge‐exposed coordinatively unsaturated Mo atoms in an Mo?O coordination polyhedron can act as activation centers to achieve the chemisorption, activation, and photoreduction of dinitrogen efficiently. Using that insight as a starting point, through rational structure and defect engineering, the optimized Bi2MoO6 sunlight‐driven nitrogen fixation system, which simultaneously possesses robust nitrogen activation ability, excellent light‐harvesting performance, and efficient charge transmission was successfully constructed. As a surprising achievement, this photocatalytic system demonstrated for the first time ultra‐efficient (1.3 mmol g?1 h?1) and stable sunlight‐driven nitrogen fixation from air in the absence of any organic scavengers. 相似文献
77.
Bangfa Ni Caijing Xiao Donghui Huang Hongchao Sun Guiying Zhang Cunxiong Liu Pingsheng Wang Haiqing Zhang Weizhi Tian 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):313-319
China Advance Research Reactor (CARR) at China Institute of Atomic Energy (CIAE), with a non-perturbed maximum thermal neutron
flux of 1 × 1015 cm−2 s−1 at the center of active area, is one of the most powerful research reactors in the world. Three neutron channels have been
allocated for conventional neutron activation analysis (NAA), thermal neutron prompt gamma activation analysis (PGAA) and
cold neutron PGAA, respectively. Two irradiation tube systems are installed in the conventional NAA channel. One of them is
for short irradiation with the rabbit size of diameter (Φ)19 × 40 mm, the other one is for long irradiation with the rabbit
size of Φ39 × 70 mm. The medium temperature is about 45 °C and the thermal neutron flux is about 3 × 1014 cm−2 s−1 at sample positions. The flux gradient is expected to be very small according to the designed neutron flux distribution.
Pneumatic systems are used for samples transfer. The speed of rabbits is designed to be about 20 m/s, and it takes 3 s to
travel from irradiation position to detector. Three sets of gamma counting systems and one delayed neutron counting system
are being equipped for routine analysis. They are designed for running continuously and automatically. And all the functions
can be operated at laboratory or office through remote controlled computer. Software has been made domestically for spectrum
peak search, concentration calculation with relative method and k0 method with interference corrections and some other functions for the convenience of users. 相似文献
78.
Bin WangGang Dai Hongchao ZhangXiaowu Ni Zhonghua ShenJian Lu 《Applied Surface Science》2011,257(23):9977-9981
In order to study the long-pulsed laser induced damage performance of optical thin films, damage experiments of TiO2/SiO2 films irradiated by a laser with 1 ms pulse duration and 1064 nm wavelength are performed. In the experiments, the damage threshold of the thin films is measured. The damages are observed to occur in isolated spots, which enlighten the inducement of the defects and impurities originated in the films. The threshold goes down when the laser spot size decreases. But there exists a minimum threshold, which cannot be further reduced by decreasing the laser spot size. Optical microscopy reveals a cone-shaped cavity in the film substrate. Changes of the damaged sizes in film components with laser fluence are also investigated. The results show that the damage efficiency increases with the laser fluence before the shielding effects start to act. 相似文献
79.
The asymmetric characteristic of a vehicle’s ability in deceleration and acceleration, as well as its impact to micro- and macroscopic traffic flow has caused increased attention from both theoretical and practical sides. However, how to realistically model this property remains a challenge to researchers. This paper is one of the two studies on this topic, which is focused on the modeling at the microscopic level from the investigation of car-following behavior. The second part of the study [H. Liu, H. Xu, H. Gong, Modeling the asymmetry in traffic flow (b): macroscopic approach, Appl. Math. Model. (submitted for publication)] is focused on the modeling of this asymmetric property from the macroscopic scale. In this paper, we first present an asymmetric full velocity difference car-following approach, in which a higher order differential equation is developed to take into account the effect of asymmetric acceleration and deceleration in car-following. Then, efforts are dedicated to calibrate the sensitivity coefficients from field data to complete the theoretical approach. Using the data recorded from the main lane traffic and ramp traffic of a segment of the US101 freeway, the two sensitivity coefficients have been successfully calibrated from both congested and light traffic environments. The experimental study reveals that in the studied traffic flow, the intensity of positive velocity difference term is significantly higher than the negative velocity difference term, which agrees well with the results from studies on vehicle mechanics. 相似文献
80.
Chongyang Liu Zhaohua Gong Enmin Feng Hongchao Yin 《Nonlinear Analysis: Hybrid Systems》2008,2(4):1168-1174
In fed-batch culture of glycerol bio-dissimilation to 1,3-propanediol (1,3-PD), the aim of adding glycerol is to obtain as much 1,3-PD as possible. Hence, a proper feed strategy is required during the process. In this paper, we present an optimal switching control model based on our proposed controlled switching system. Some properties of the controlled switching system are obtained. Subsequently, we prove the existence of optimal control. In order to deduce the optimality conditions, we transcribe the optimal switching control model into an equivalent one with fixed switching instants and parameters. Finally, the optimality conditions of the equivalent problem are investigated by calculus of variations. 相似文献