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971.
Chemical industries, from their very inception, have been controversial due to the high risks they impose on safety of human beings and the environment. Recent decades have witnessed increasing impacts of the accelerating expansion of chemical industries and chemical accidents have become a major contributor to environmental and health risks in China. This calls for the establishment of an effective chemical risk management system, which requires reliable, accurate and comprehensive data in the first place. However, the current chemical accident-related data system is highly fragmented and incomplete, as different responsible authorities adopt different data collection standards and procedures for different purposes. In building a more comprehensive, integrated and effective information system, this article: (i) reviews and assesses the existing data sources and data management, (ii) analyzes data on 976 recorded major hazardous chemical accidents in China over the last 40 years, and (iii) identifies the improvements required for developing integrated risk management in China. 相似文献
972.
Kunpeng Guo Junli Yang Xiaofan Shi Xiaoqing Lu Jun Cheng Yuling Wu Yun Guo Hua Wang 《Materials Chemistry and Physics》2014
Solid-state emissive organic materials have received increasing attention due to their prospective applications in large-area. Here, a novel π-extended tetrathiafulvene derivative DPD with donor-π-donor structure has been newly developed to produce the prominent characteristic of aggregation-induced enhanced emission (AIEE) that exhibits higher fluorescence quantum efficiency in solid film compare to its solutions. The AIEE mechanism of DPD was studied in detail through photophysical investigations and can be dominant attributed to the formed excimer state of DPD and J-aggregates in solid state. 相似文献
973.
A Tetraphenylethylene Core‐Based 3D Structure Small Molecular Acceptor Enabling Efficient Non‐Fullerene Organic Solar Cells 下载免费PDF全文
974.
Phosphorene as a Polysulfide Immobilizer and Catalyst in High‐Performance Lithium–Sulfur Batteries 下载免费PDF全文
975.
Multimodal medical image fusion based on discrete Tchebichef moments and pulse coupled neural network 下载免费PDF全文
Lu Tang Jiansheng Qian Leida Li Junfeng Hu Xiang Wu 《International journal of imaging systems and technology》2017,27(1):57-65
Multimodal medical image fusion plays a vital role in clinical diagnoses and treatment planning. In many image fusion methods‐based pulse coupled neural network (PCNN), normalized coefficients are used to motivate the PCNN, and this makes the fused image blur, detail loss, and decreases contrast. Moreover, they are limited in dealing with medical images with different modalities. In this article, we present a new multimodal medical image fusion method based on discrete Tchebichef moments and pulse coupled neural network to overcome the aforementioned problems. First, medical images are divided into equal‐size blocks and the Tchebichef moments are calculated to characterize image shape, and energy of blocks is computed as the sum of squared non‐DC moment values. Then to retain edges and textures, the energy of Tchebichef moments for blocks is introduced to motivate the PCNN with adaptive linking strength. Finally, large firing times are selected as coefficients of the fused image. Experimental results show that the proposed scheme outperforms state‐of‐the‐art methods and it is more effective in processing medical images with different modalities. © 2017 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 27, 57–65, 2017 相似文献
976.
构建离子液体1-乙基-3-甲基咪唑醋酸盐[EMIM]OAc与纤维素的均相体系,采用酶原位降解法,以3,5-二硝基水杨酸法表征降解效果,考察各因素的影响确定最佳工艺条件:6.6 g 3%(质量分数)原溶液与4 mL pH4.6柠檬酸钠缓冲溶液组成均相体系、6 mg酶、50℃、26 h,酶解率迭78.5%,比非均相下提高了... 相似文献
977.
The asymmetry appearing in the degree of polarization (DOP) distribution of the backscattering polarized light from tissues is investigated by using polarized Monte Carlo simulation. When the incident point is close to the boundary of the lesion inside the tissue, high asymmetry emerges regardless of the polarized direction of the incident light. A noninvasive method based upon the DOP asymmetry of the backscattering light is proposed to locate lesions hidden in live tissues by scanning a point light source. Imaging of the front projection on complicated lesion structures is demonstrated with this method. Its transverse resolution, which is affected by the wavelength of incident light and the size of the scattering particle, can reach the diameter of the lesion scattering particle theoretically while the best longitudinal detection depth can be achieved by choosing a suitable incident wavelength according to the scattering characters of the tissue. 相似文献
978.
979.
980.
CuO nanowires with high crystalline quality are synthesized via a simple thermal oxidation method. Charge conduction on individual nanowires under a transverse electric field exhibits an intrinsic p-type semiconducting behavior. Variations in signal transducer in different chemical gas environments are measured on individual CuO nanowire field effect transistors. They demonstrate good performance to both NO(2) and ethanol gasses. In particular, the nanowire chemical sensor reveals a reverse response to ethanol vapor under temperature variation. Experimental results and first-principles calculations indicate that ethanol is oxidized in air at high temperature, resulting in the production of CO(2) and H(2)O. The strong H(2)O adsorption leads to the reversal behavior, due to the electron transfer from H(2)O molecules to the CuO surface. 相似文献