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Use of infrared thermal imaging to diagnose health of Ammopiptanthus mongolicus in northwestern china

Journal of Forestry research 2015年第3期26卷 605-612页

作者： Weijie Yuan Yi Yu Yongde Yue Ji Wang Fengchun Zhang Xiaohong Dang International Centre for Bamboo and Rattan Forestry Experiment Center of North china Chinese Academy of Forestry College of Ecology and Environmental Science Inner Mongolia Agricultural University Foreign Economic Cooperation Office Ministry of Environmental Protection

Population of the rare and endangered species Ammopiptanthus mongolicus （Maxim.） Cheng f. declined rapidly in china＇s add region and Central Asia. There is an urgent need to protect this species, which is particularly important in maintaining biodiversity throughout the arid region of northwestern china. By analyzing the infrared thermal images based on plant-transpiration transfer coef- ficient （hat） and photosynthetic parameters, we made quantitative and accurate diagnoses of the plant growth and health status of A. mongolicus. Using an LI-COR6400 photosynthesis system, we measured the net photosynthetic rate （Pn）, stomatal conductance （Gs）, and transpiration rate （Tr）. Infrared thermal images obtained in the field were processed by ENVI4.8 software to calculate surface tem- peratures of the plant subjects. We found that the plant transpiration transfer coefficient of A. mongolicus was inthe order of old plants 〉young plants 〉intermediate-aged plants. Declining health levels of young, intermediate, and old plants were divided into three categories：〈0.4, 0.4-0.7, and 〉0.7. The coefficient showed a significant negative correlation with Tr, Gs, and Pn, indicating that they can simultaneously reflect the state of plant growth. By estab- lishing hat and photosynthetic parameters in regression model Y = a-blnx, we can accurately diagnose plant growth and decline of plant health conditions.

关键词： Photosynthetic parameters Plant stress Stomatal conductance Thermography Three-temperature(3T) model Plant-transpiration transfer coefficient

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Measurements of NO_2 mixing ratios with topographic target light scattering-differential optical absorption spectroscopy system and comparisons to point monitoring technique

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Chinese Physics B 2012年第11期21卷 285-290页

作者：王杨李昂谢品华曾议王瑞斌陈浩裴显刘建国刘文清 Key Laboratory of Environmental Optical&Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences china national Environmental Monitoring Center

A topographic target light scattering-differential optical absorption spectroscopy （＇IbTaL-DOA~） system is de- veloped for measuring average concentrations along a known optical path and studying surface-near distributions of atmospheric trace gases. The telescope of the ToTaL-DOAS system points to targets which are located at known dis- tances from the measurement device and illuminated by sunlight. Average concentrations with high spatial resolution can be retrieved by receiving sunlight reflected from the targets, A filed measurement of NO2 concentration is performed with the ToTaL-DOAS system in Shijiazhuang in the autumn of 2011. The measurement data are compared with con- centrations measured by the point monitoring technique at the same site. The results show that the ToTaL-DOAS system is sensitive to the variation of NO2 concentrations along the optical path.

关键词： atmospheric optics target light scattering-differential optical absorption spectroscopy(ToTaL-DOAS) atmospheric trace gas averaging mixing ratio

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Effect of Kushen(Radix Sophorae flavescentis) extract on laryngeal neoplasm Hep2 cells

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Journal of Traditional Chinese Medicine 2013年第2期33卷 218-222页

作者： Yingzi Wang Chunchao Han Xinsheng Fang Xinyuan Shi Ailing Feng Kuibang He Shenghai Zhang Xiuyu Sun School of Chinese Materia Medica Beijing University of Chinese Medicine School of Pharmacy Shandong University of Traditional Chinese Medicine College of Agronomy Shandong Agricultural University

OBJECTIVE:To evaluate the effect of fermented extract of Kushen(Radix Sophorae Flavescentis) or non-fermented ESF on laryngeal neoplasms Hep2 ***:Use 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay to explore the effect of fermented ESF and non-fermented ESF on Hep2 cells,and detect the mRNA and protein expression level of Bcl-2,Bax and Caspase-3 with reverse transcription polymerase chain reaction(RT-PCR) andWestern ***:Both fermented ESF and non-fermented ESF could inhibit laryngeal neoplasm's Hep2 cells,but and the cells did not response to the dilution 1:320 of fermented ESF,nor to the 1:1280 dilution of non-fermented *** time progressed,the dilution 1:80 of fermented ESF and 1:320 dilution of non-fermented ESF could significantly reduce Bcl-2 mRNA and protein expression and down-regulate Caspase-3 mRNA and protein *** mRNA and protein were not expressed in Hep2 ***:Both fermented ESF and non-fermented ESF could inhibit the proliferation of Hep2 cells,and the effect of non-fermented ESF was significantly better than that of the fermented.

关键词： Sophora flavescens Fermentation La-ryngeal neoplasm

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Intraspecific leaf morphological variation in Quercus dentata Thunb.:a comparison of traditional and geometric morphometric methods,a pilot study

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Journal of Forestry research 2022年第6期33卷 1751-1764页

作者： Kaiyu Yang Jianghao Wu Xinman Li Xinbo Pang Yangchen Yuan Guohui Qi Minsheng Yang College of Forestry Hebei Agricultural UniversityBaoding 071000HebeiPeople’s Republic of China Hebei Key Laboratory for Tree Genetic Resources and Forest Protection Baoding 071000HebeiPeople’s Republic of China Administration Bureau of Hongyashan State Owned Forest Farm in Yixian County Yixian 074200HebeiPeople’s Republic of China research Center for Walnut Engineering and Technology of Hebei Lincheng 054300HebeiPeople’s Republic of China Institute of Walnut industry Technology of Hebei Province(Xingtai) Lincheng 054300HebeiPeople’s Republic of China

To compare the application of traditional morphometric methods(TMMs)and geometric morphometric methods(GMMs)in the study of intraspecific leaf morphological characters of Quercus dentata,fifteen linear measurement indices and thirteen landmarks of leaves were used to study leaf morphology of three provenances(H1,H2,and H3).In TMMs,principal component analysis(PCA)showed that leaf size–related indices played an important role in population *** least square(PLS)analysis showed that the main morphological characters affecting leaf size were the average depth of the lobes and the length–width ***,the important indices to distinguish the provenances were circularity,leaf width,and length–width *** results of discriminant analysis(DA)showed that 74.0%of H1,68.0%of H2,and 74.0%of H3 were correctly *** analysis showed that the Mahalanobis distances between H1 and H2,H1 and H3,and H2 and H3 were 4.3761,11.4629,and 10.2067,*** GMMs,PCA based on symmetrical components showed that the difference in leaf morphology was mainly due to the changing trend of the leaf apex and base,petiole length,and degree of leaf *** analysis showed that there was a significant covariation between the leaf symmetrical components and size:as the leaf enlarged,the widest part gradually moved up,and the shape changed from nearly oval to *** results showed that 86.0%and 78.0%of H1 and H2,70.0%and 80.0%of H1 and H3,and 82.0%and 76.0%of H2 and H3 were correctly *** variate analysis results showed that the Mahalanobis distances between H1 and H2,H1 and H3,and H2 and H3 were 1.7238,1.5380,and 1.6329,*** GMMs and TMMs showed significant differences in morphology among the three *** provenances,but GMMs had higher classification accuracy and could provide more information about leaf shape,whereas TMMs could provide more information about leaf *** on our results,GMMs are promising in t

关键词： Traditional morphometrics Geometric morphometrics Leaf morphology variation Quercus dentata Intraspecific

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Wetland Economic Valuation Approaches and Prospects in china

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Chinese Geographical Science 2016年第2期26卷 143-154页

作者： JIANG Bo Christina P.WONG CUI Lijuan OUYANG Zhiyun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051 China School of Sustainability Arizona State University Tempe AZ 85287 US.A Institute of Wetland research Chinese Academy of Forestry Beijing 100091China

Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-being explicit. Economic valuation can help management by clarifying the full range of benefits and costs of proposed management actions. In the past two decades, economic valuation of wetland ecosystem services has become one of the most significant scientific priorities for wetland protection. In this paper, we provide an overview of ecosystem services, and summarize the main interdisciplinary approaches to measure and value wetland ecosystem services. We identified four main methodological gaps preventing progress on wetland valuation of ecosystem services in china, which are: 1) confusion on terminology like intermediate and final ecosystem services, 2) lack of ecological production functions to link ecosystem characteristics to final ecosystem services, 3) static valuation making it difficult to evaluate the trade-offs and synergies among ecosystem services, and 4) lack of clear guidance on relating ecological compensation programs to conservation targets. Overcoming these gaps is important to inform wetland compensation mechanisms and conservation policies. We propose future research on wetland ecosystem services in china should be focused on: 1) defining final ecosystem services based on beneficiary preferences and underlying biophysical mechanisms, 2) establishing wetland monitoring programs at specific sites to collect data on final ecosystem service indicators and ecosystem characteristic metrics to create ecological production functions for economic valuation and rescaling techniques, and 3) incorporating wetland ecosystem service values into decision-making processes to inform wetland management.

关键词： ecosystem services wetlands economic valuation methodological gaps china

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Promoting effect and mechanism of neodymium on low-temperature selective catalytic reduction with NH3 over Mn/TiO2 catalysts

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Journal of Rare Earths 2020年第11期38卷 1215-1223,I0003页

作者： Peng Wu Yaping Zhang Ke Zhuang Kai Shen Sheng Wang Tianjiao Huang Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China State Power Environmental Protection research Institute Nanjing 210031China

Series of Mn/TiO2 catalysts modified with various contents of Nd for low-temperature SCR were *** can be found that the appropriate amount of Nd can markedly reduce the take-off temperature of Mn/TiO2 catalyst to 80℃and NOx conversion is stabilized over 90%in the wide temperature range of 100-2600 C.0.1 Nd-Mn/Ti shows higher N2 selectivity and better SO2 resistance than Mn/Ti *** results reveal that Nd-doped Mn/TiO2 catalyst exhibits larger BET surface area and better dispersion of active component *** results indicate that the optimal 0.1 Nd-Mn/Ti sample possesses higher concentration of Mn4+and larger amount of adsorbed oxygen at the surface compared with the unmodified *** situ DRIFTS show that the surface acidity is evidently increased after adding Nd,especially,the Lewis acid sites,and the intermediate(-NH2)is more *** reaction mechanism over Mn/Ti and 0.1 Nd-Mn/Ti catalysts obey the Eley-Rideal(E-R)mechanisms under low temperature reaction conditions.H2-TPR results show that Nd-Mn/TiO2 catalyst exhibits better lowtemperature redox properties.

关键词： Nd modification Mn/TiO2 catalyst Low-temperature Selective catalyst reduction Mechanism Rare earths

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Feature Selection by Merging Sequential Bidirectional Search into Relevance Vector Machine in Condition Monitoring

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1248-1253页

作者： ZHANG Kui DONG Yu BALL Andrew School of Economics & Management Wuhan Polytechnic University School of Information Engineering Communication University of China School of Computing & Engineering University of Huddersfield

For more accurate fault detection and diagnosis, there is an increasing trend to use a large number of sensors and to collect data at high frequency. This inevitably produces large-scale data and causes difficulties in fault classification. Actually, the classification methods are simply intractable when applied to high-dimensional condition monitoring data. In order to solve the problem, engineers have to resort to complicated feature extraction methods to reduce the dimensionality of data. However, the features transformed by the methods cannot be understood by the engineers due to a loss of the original engineering meaning. In this paper, other forms of dimensionality reduction technique（feature selection methods） are employed to identify machinery condition, based only on frequency spectrum data. Feature selection methods are usually divided into three main types： filter, wrapper and embedded methods. Most studies are mainly focused on the first two types, whilst the development and application of the embedded feature selection methods are very limited. This paper attempts to explore a novel embedded method. The method is formed by merging a sequential bidirectional search algorithm into scale parameters tuning within a kernel function in the relevance vector machine. To demonstrate the potential for applying the method to machinery fault diagnosis, the method is implemented to rolling bearing experimental data. The results obtained by using the method are consistent with the theoretical interpretation, proving that this algorithm has important engineering significance in revealing the correlation between the faults and relevant frequency features. The proposed method is a theoretical extension of relevance vector machine, and provides an effective solution to detect the fault-related frequency components with high efficiency.

关键词： feature selection relevance vector machine sequential bidirectional search fault diagnosis

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Integrated rice management simultaneously improves rice yield and nitrogen use efficiency in various paddy fields

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Pedosphere 2020年第6期30卷 863-873页

作者： Yujiao DONG Fanwen ZENG Jiang YUAN Guangbin ZHANG Yuanxue CHEN Xuejun LIU Padilla HILARIO Tusheng REN Shihua LU College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China Soil and Fertilizer Institute Sichuan Academy of Agricultural SciencesChengdu 610066China Bureau of Agriculture in Shehong County Suining CitySichuan ProvinceShehong 629200China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Sichuan Agricultural University Wenjiang 611130China Kadoorie Farm and Botanic Garden Hong Kong 999077China

The hilly area of Southwest china is a typical rice production area which is limited by seasonal droughts and low temperature in the early rice growth period.A field experiment was conducted on three typical paddy fields(low-lying paddy field,medium-elevation paddy field,and upland paddy field)in this ***(N)treatment(180 kg N ha-1 year-1)was compared to a control treatment(0 kg N ha-1 year-1)to evaluate the effects of integrated rice management(IRM)on rice growth,grain yield,and N *** rice management integrated raised beds containing plastic mulch,furrow irrigation,and triangular *** comparison to traditional rice management(TRM),IRM promoted rice tiller development,with 7–13 more tillers per cluster at the maximum tillering stage and 1–6 more tillers per cluster at the end of tillering *** rice management significantly increased the rice aboveground biomass by 34.4%–109.0%in different growth periods and the aboveground N uptake by 25.3%–159.0%.Number of productive tillers significantly increased by 33.0%,resulting in a 33.0%increase in grain yield and 8.0%improvement of N use efficiency(NUE).Grain yields were significantly increased in all three paddy fields assessed,with IRM being the most important factor for grain yield and productive tiller *** of paddy field type and N level on N uptake by aboveground plants were reflected in the rice reproductive growth period,with the effects of IRM more striking due to the dry climate *** conclusion,IRM simultaneously improved rice yield and NUE,presenting a valuable rice management technique in the paddy fields assessed.

关键词： grain yield hilly area nitrogen uptake paddy field type plastic mulch traditional rice management

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Effect of vacuum degree and aeration rate on sludge dewatering behavior with the aeration-vacuum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第9期11卷 638-655页

作者： Yu-feng GAO Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University Nanjing 210098 China Geotechnical research Institute Hohai University Nanjing 210098 China The Science and Technology Division Hohai University Nanjing 210098 China

Due to large-scale dredging operations, a large amount of sludge is inevitably produced. Large areas of land are occupied when the dredged sludge is discarded in the disposal site as waste material. The sludge dewatering with aeration-vacuum (SDAV) method is suit for treating the sludge with high water content and high clay content in the disposal site. The water in the sludge can be discharged out. The volume of the sludge can be reduced quickly, and the recycling of the land can be accelerated by this method. Most importantly, this technique is an efficient way to deal with clogging problems when pumping water from high water content, high clay content dredged sludge. Vacuum degree range tests, the aeration rate range tests, and the influencing factors of sludge dewatering behavior tests were conducted with a self-developed SDAV model test device. Sludge samples were taken from the South-to-North Water Diversion East Line Project in Huai’an White-Horse Lake disposal site, Jiangsu Province, china. The optimal range of vacuum degree and aeration rate were obtained through the test results, and the mechanisms for how the two factors work and how they affect the sludge dewatering behavior were analyzed. The suitable vacuum degree range in SDAV is below 50 kPa, and the suitable aeration rate is about 1.0 m3/h. The low-vacuum degree contributes to reduce the ad-sorption effect of micro-channels on soil particles in filter material and to maintain the arch structures. Aeration has the effects of expansion, disturbance, changing Reynolds number, and dynamic sieve separating. The pump quantity of water per meter of filter tube (m) has different change rules as the vacuum degree changes under different aeration rates. The reason is that the formed arch structures’ conformation and permeability differ greatly under different combined-conditions of vacuum degree and aeration rate. The optimal combined-condition for dewatering the sludge is 35 kPa with 1.0 m3/h.

关键词： High water content dredged sludge Sludge dewatering with aeration-vacuum (SDAV) Vacuum degree Aeration rate Arch structures

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MIMO Underwater Acoustic Communication in Shallow Water with Ice Cover

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china Ocean Engineering 2019年第2期33卷 237-244页

作者： HAN Xiao YIN Jing-wei LIU Bing GUO Long-xiang Acoustic Science and Technology Laboratory Harbin Engineering University Key Laboratory of Marine Information Acquisition and Security (Harbin Engineering University) Ministry of Industry and Information Technology College of Underwater Acoustic Engineering Harbin Engineering University

Although multiple-input multiple-output(MIMO) underwater acoustic(UWA) communication has been intensively investigated in the past years, existing works mainly focus on open-water environment. There is no work reporting MIMO acoustic communication in under-ice environment. This paper presents results from a recent MIMO acoustic communication experiment which was conducted in Bohai Gulf during winter. In this experiment, high frequency MIMO signals centered at 10 kHz were transmitted from a two-element source array to a four-element vertical receiving array at 1 km range. According to the received signal of different array elements, MIMO acoustic communication in under-ice environment suffers less effect from co-channel interference compared with that in open-water environment. In this paper, time reversal followed by a single channel decision feedback equalizer is used to process the experimental data. It is demonstrated that this simple receiver is capable of realizing robust performance using fewer hydrophones(i.e. 2) without the explicit use of complex co-channel interference cancelation algorithms, such as parallel interference cancelation or serial interference cancelation.

关键词： underwater acoustic communication MIMO shallow water ice cover

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