检索结果-南通市图书馆

Study on the relative radiometric correction of CBERS satellite CCD image

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2005年第S2期48卷 12-28页

作者： GUO Jianning, YU Jin, ZENG Yong, XU Jianyan, PAN Zhiqiang & HOU Minghui China center for resource Satellite Data and Application, Beijing 100830, China China center for resource Satellite Data and Application Beijing China

The main payload on CBERS-01/02 of China-Brazil Earth resources Satellite (CBERS) is a push-broom CCD camera with moderate spatial and radiant resolution. Because at lab the data for calibration at satellite assembly stage were unable to be collected, and also because the onboard calibrator after launch was in a different state from imaging, the calibration of CCD image got a series of difficulties involved. In practice, two methods are used in the processing on the ground station: One is extracting calibration data by statistics from the image itself, and the other is the method of histogram match. It was proved that the latter can calibrate the image much better, because it can remove the effect of unstable response of the camera largely and also can overcome the nonlinearity of the camera basically by using Look-Up Table (LUT) calculated from histogram statistics of different temporal images. Considering the problems of CBERS-01, a lot of calibration tests were done before the launch of CBERS-02, in which a set of lab coefficients for relative calibration was formulated after the data collection by using integration-hemisphere in the stage of satellite assembly test. During the on-orbit test, it was found that the calibration result from such coefficients was not satisfying, especially there being response difference between 3 detector arrays, which was attributed to the unstable dark currents of the CCD camera. This paper comes up with a statistic method to remove such response difference. In this method the middle detector array was used as reference to find the response differences of adjacent similar features between these arrays and it was proved to have a broad adaptability.

关键词： CBERS satellite CCD camera relative radiometric calibration relative radiometric correction assembly test.

Salinity intrusion characteristics analysis using EFDC model in the downstream of Geum River

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2010年第6期22卷 934-939页

作者： Sangman Jeong Kyusung Yeon Youngteck Hur Kukryul Oh Department of Civil and Environmental Engineering Kongju National University Water resource Operation center

As social interest in the environmental conservation and ecological restoration has recently increased, more research works have been done to resolve problems concerning environmental management of estuaries. In this study, a three-dimensional numerical model, Environmental Fluid Dynamics Code （EFDC） was used in the analysis of the salinity intrusion characteristics in the downstream of Geum River. The numerical simulation was performed to investigate the influence range for salinity intrusion when the gates were fully opened. The conditions used for simulation were the four flow regimes in Geum River Basin, Korea. Results indicated that the ranges of salinity intrusion from the barrage were 50.72 km （drought flow）, 48.87 km （low flow）, 46.56 km （normal flow） and 42.10 km （flood flow）. These results indicated that the EFDC model used for numerical simulation has high accuracy. The result concluded in this study can be used as a basis in understanding the extent of salinity intrusion effects at different flow rates.

关键词： Environmental Fluid Dynamics Code salinity intrusion barrage

Potential recoverable natural gas resources in China

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2008年第1期5卷 83-86页

作者： Liu Chenglin Zhu Jie Che Changbo Liu Guangd School of resource and Information China University of Petroleum Beijing 102249 China Oil and Gas resource Strategy Research center of the Ministry of Land and resource Beijing China

Natural gas resources in China are abundant. The undiscovered recoverable natural gas resources in China are estimated to be 19.27 ×10^12 m^3. Natural gas is mainly distributed in the middle and west China and offshore areas of China. The Tarim Basin, Sichuan Basin, Ordos Basin, East China Sea Basin, Tsaidam Basin, Yinggehai Basin, and Qiongdongnan Basin are the main gas-bearing basins. The natural gas resources are not distributed evenly and are under-explored in China. The deeper horizons in east China, foreland basins and craton paleo-uplifts in the middle and west China, and the offshore basins are the main exploration areas in the future.

关键词： Natural gas resources exploration area China

Xylooligosaccharides (XOS) as Emerging Prebiotics: Its Production from Lignocellulosic Material

在线全文

学校读者我要写书评

暂无评论

Advances in Microbiology 2019年第1期9卷 14-20页

作者： Nutan Mhetras Vidhyashri Mapre Digambar Gokhale Symbiosis School of Biological Sciences Symbiosis University Pune India ncim resource center CSIR-National Chemical Laboratory Pune India

Prebiotics are non-digestible food supplements (oligosaccharides) which play an important role in stimulating the growth of beneficial bacteria especially Lactobacilli and Bifidobacteria in the colon of the host. Xylooligosaccharides (XOS) are more effective than other oligosaccharides such as fructo-oligosaccharides as dietary supplements. Chemical methods are preferred to produce XOS mixtures with a wide DP range, while enzymatic methods are preferred in the food or pharmaceutical industries to reduce formation of degradation products. With the growing importance of making fuels fromlignocellulosic biomass (LCM) and the increasing demand for XOS, more opportunities are emerging to utilize xylan-rich component generated in biorefinery into high-value products such as XOS that could further lower the cost of LCM derived biofuels.

关键词： Xylooligosaccharides Prebiotics Xylanase

ADSORPTION OF HUMIC SUBSTANCES BY MACRO WEAKLY BASIC IONEXCHANGE RESIN AND THEIR EFFECTS ON REMOVAL OF Cu^(2+) AND Pb^(2+)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2010年第3期28卷 427-435页

作者：李爱民 State Key Laboratory of Pollution Control and resource Reuse School of the Environment Nanjing University Research center of Organic Toxic Substance Control and resource Reuse of Jiangsu Province

Adsorption of humic, tannic and gallic acids by a macro weakly basic ion-exchange resin JN-01 was studied. The adsorption capacity of this resin for gallic and tannic acids is much higher than that for humic acid, which can be explained on the basis of both their molecular size and ionization degree. Furthermore, humic acid is separated into different components with molecular weight in the range from 2000 Da to 100000 Da by ultra-filter, and their adsorption isotherms on resin JN-01 indicate that humic acid＇s molecular weight is an important factor which makes significant influence on adsorption. Finally, changes in the amount of Cu^2＋ and Pb^2＋ adsorbed on resin JN-01 as a function of the concentration of each of these three acids were studied. A large increase in the heavy metal ions uptake is observed in the presence of humic substance, such advantages are due to the interactions between the heavy metal ions and the unbound functional groups of the adsorbed organic acids.

关键词： Adsorption Humic substance Macro weakly basic ion-exchange resin Removal Heavy metal

ADSORPTION STUDIES OF TANNIC ACID BY COMMERCIAL ESTER RESIN XAD-7

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2010年第2期28卷 231-239页

作者：李爱民 State Key Laboratory of Pollution Control and resource Reuse School of the EnvironmentNanjing University Research center of Organic Toxic Substance Control and resource reuse of Jiangsu Province

Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7 and D-201 are performed, and all data indicates resin XAD-7 can be used as an effective adsorbent for removing tannic acid during water/wastewater treatment. Furthermore, adsorption thermodynamics studies indicate different adsorption mechanisms for TA on XAD-7 and D-201. FT-IR and solid state 13C-NMR spectroscopy are used to explain the adsorption force between XAD-7 and TA. It suggests that hydrogen bonding is the main adsorption force for TA. Finally, XAD-7＇s adsorption capacity in the presence of different metal ions is investigated, which indicates that heavy metal ions in solutions can decrease the adsorption capacity for TA on ester resin XAD-7.

关键词： Adsorption Tannic acid Resin XAD-7 Metal ion.

Abnormal energy metabolism and tau phosphorylation in the brains of middle-aged mice in response to atmospheric PM2.5 exposure

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第12期29卷 145-153页

作者： Rui Gao Tingting Ku Xiaotong Ji Yingying Zhang Guangke Li Nan Sang College of Environment and resource Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter（PM_（2.5）） can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM_（2.5） inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM_（2.5） ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM_（2.5） inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.

关键词： Fine particulate matter(PM_(2.5)) Mitochondrial structure and function Energy metabolism Reactive oxygen species(ROS) Tau phosphorylation

Review of the research on the development and utilization of clay-type lithium resources

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第4期87卷 46-53页

作者： Ruiqi Xie Zhihui Zhao Xiong Tong Xian Xie Qiang Song Peiqiang Fan Faculty of Land resource Engineering Kunming University of Science and TechnologyKunming650093China Yunnan Engineering Research center for Metal Tailings resource Utilization Kunming650093China

Since the demands for lithium have been in explosive growth recently and several great clay lithium resources were founded in China,the development and utilization of clay-type lithium resources become a hot *** order to provide a guidance for the concentration and extracting lithium of clay-type lithium resources,this review systematically summarized the main types and characteristics of clay-type lithium resources and the research status of lithium extraction from clay lithium ***,the flotation research status of the main mineral of clay lithium ore was also ***,we discussed the difficulties in the development and utilization of clay-type lithium ore and put forward the subsequent research *** paper can provide a guidance for the con-centration and extracting lithium of clay-type lithium resources in the future.

关键词： Clay lithium Clay mineral flotation Lithium extraction Leaching

Synergistic effect of microwave irradiation and CaF2 on vanadium leaching

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 156-163页

作者： Jing-peng Wang Yi-min Zhang Jing Huang Tao Liu School of resource and Environmental Engineering Wuhan University of Science and Technology Wuhan 430081 China Hubei Provincial Engineering Technology Research center of High Efficient Cleaning Utilization for Shale Vanadium resource Wuhan 430081 China Hubei Provincial Collaborative Innovation center for High Efficient Utilization of Vanadium resource Wuhan 430081 China

The effect and mechanism of microwave irradiation on vanadium leaching were studied via a comparison between microwave heating and conventional heating. The results show a synergistic effect of microwave irradiation and calcium fluoride （CaF2） on the vana- dium leaching efficiency. It is confirmed that the vanadium leaching process can be improved by microwave irradiation when CaF2 is present. The leaching rate of vanadium under microwave irradiation is increased by 8%-15% when 5wt% CaF2 is added; by contrast, in the absence of CaF2, the leaching rate is almost unaffected compared to that by conventional heating. Morphological analysis reveals that the particles are gradually eroded by acid under microwave irradiation, whereas some of the fine particles in samples subjected to conventional heating are tightly covered by a flocculent silicate product. Moreover, a large amount of A1 and V and a small amount of Si are dissolved from samples under microwave heating, as revealed by the elemental analysis of leachates. Fourier transform infrared spectroscopic analysis also indicates a higher mass transfer coefficient in the diffusion layer of the raw material by microwave irradiation. When CaF2 is present, the reaction energy barrier is lowered and the leaching process is controlled by the tightly covered product layer, resulting in a prominent effect of mi- crowave irradiation.

关键词： vanadium extraction leaching microwave irradiation calcium fluoride synergistic effects