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Effect of Long-Term Fertilization on Organic Carbon and Nitrogen in a Subtropical Paddy Soil

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Pedosphere 2009年第6期19卷 727-734页

作者： HUANG Qian-Ru HU Feng HUANG Shan LI Hui-Xin YUAN Ying-Hong PAN Gen-Xing zhang Wei-Jian college of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 (China) Jiangxi Institute of Red Soils Jinxian 331717 (China) Institute of Applied Ecology Nanjing Agricultural University Nanjing 210095 (China)

A long-term experiment beginning in 1981 in Jinxian County of Jiangxi Province, subtropical china, was conducted in a paddy field under a double rice cropping system with four different fertilization regimes, including 1) no fertilizer as control (CK), 2) balanced chemical N, P, and K fertilizers (NPK), 3) organic manure using milk vetch and pig manure in the early and late rice growing season, respectively (OM), and 4) balanced chemical fertilizers combined with organic manure (NPKM). Samples (0-17 cm) of the paddy field soil, which was derived from Quaternary red clay, were collected after the late rice harvest in November 2003 for determination of total organic carbon (TOC) and total nitrogen (TN) and fractions of organic C and N. Results showed that TOC and TN in the NPKM and OM treatments were significantly higher than those in other two treatments (CK and NPK). Application of organic manure with or without chemical fertilizers significantly increased the contents of all fractions of organic C and N, whereas chemical fertilizer application only increased the contents of occluded particulate organic C (oPOC) and amino acid N. In addition, application of organic manure significantly enhanced the proportions of free particulate organic carbon (fPOC) and oPOC in total C, and those of amino sugar N and amino acid N (P < 0.01) in total N. In contrast, chemical fertilizer application only increased the proportions of oPOC and amino acid N (P < 0.05). There were no significant differences in either contents or proportions of soil organic C and organic N fractions between the NPKM and OM treatments. These indicated that organic manure application with or without chemical fertilizers played the most significant role in enhancing soil organic C and N quantity and quality in the paddy field studied.

关键词： chemical fertilizers double rice cropping system organic manure

Mine laneway 3D reconstruction based on photogrammetry

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中国有色金属学会会刊：英文版 2011年第S3期21卷 686-691页

作者： zhang Chun-sen college of Geomatics, Xi’an university of science and Technology, Xi’an 710054, china college of Geomatics Xi'an University of Science and Technology Xi'an 710054 China

Aiming at the problem of 3D reconstruction for mine laneway, the technique route and step were given based on digital close range photogrammetry and traverse surveying. 3D coordinates of laneway traverse point, photogrammetric station, control strip points were obtained by electronic total station based on mine coordinate system. The feature points were extracted from the scene images. The camera was calibrated by direct linear transformation (DLT). 3D relative coordinates of the arbitrary feature points in mine laneway were calculated after feature points being matched, in which the origin of coordinate system is photogrammetric station. The 3D absolute coordinates of the feature points in mine laneway can be obtained by the combined adjustment of photogrammetry and non-photogrammetric observations and coordinate conversion. The measurable 3D model of the underground laneway terrain surface was constructed with the 3D coordinates of feature points on the image pairs obtained. The measurable 3D model of a corridor was reconstructed by the mentioned method and the experiment precision with an average standard deviation of 0.013 6 m between the 3D model and practical measure was obtained by electronic total station. The experimental resulted show the validity of the proposed approach.

关键词： digital mine mine laneway photogrammetry 3D reconstruction direct linear transformation (DLT)

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, zhang Jing and JIA Li ( college of Life and Environment science, Harbin Normal university, Harbin 150080, china college of Resources Environment & Tourism, Capital Normal university, Beijing 100037, china college of Economics and Management, Northeast agricultural university, Harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China. college of Resources Environment & Tourism Capital Normal University Beijing 100037 China. college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

Anticancer effect of two diterpenoid compounds isolated from Annona glabra Linn

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Acta Pharmacologica Sinica 2004年第7期25卷 91-96页

作者： Yong-hong zhang2, Hai-yan PENG3, Guo-hao XIA3, Ming-yan WANG3, Ying HAN4 First Clinical college 3Basic Medicine college, nanjing university of TraditionalChinese Medicine, nanjing 210029 4Jiangsu Institute of Materia Medica, nanjing 210009, china First Clinical college Basic Medicine college Nanjing University of Traditional Chinese Medicine Jiangsu Institute of Materia Medica

AIM: To study the inhibitory effect of two diterpenoid compounds isolated from Annona glabra Linn (Cunabic acid and ent-kauran-19-al-17-oic acid) on the proliferation of Human Liver Cancer (HLC) cell line SMMC-7721 and its mechanism. METHODS: Inhibition of cell proliferation was measured by MTT assay. The morphological changes of SMMC-7721 cells were observed under inverted phase-contrast microscope, fluorescent microscope, transmission electron microscope (TEM), and scanning electron microscope (SEM). Flow cytometer (FCM) was used to calculate the cell apoptotic rate, and immunohistochemical staining was used to observe the regulation of gene expression. RESULTS: The proliferation of SMMC-7721 cells was obviously inhibited after being treated with Cunabic acid at the concentration >5 μmol/L and ent-kauran-19-al-17-oic acid >10 μmol/L. The biggest inhibitory effect was 81.05 % when treated with Cunabic acid at the concentration of 25 μmol/L. The effect had a linear relationship with concentration. The result indicated that drug-treated cells exhibit typical morphological changes of apoptosis, including condensed chromatin and a reduction in volume. Sub-G0/G1 peak was found by FCM analysis and the cell cycle was arrested at G0/G1 stage. The apoptotic rates of the cells treated by Cunabic acid and ent-kauran-19-al-17-oic acid were 43.31 % and 24.95 %, respectively. It was visualized by immunohis- tochemical staining that the drugs down-regulated the gene expression of bcl-2 gene and up-regulated that of bax gene. CONCLUSION: The two diterpenoid compounds isolated from Annona glabra Linn, Cunabic acid and ent- kauran-19-al-17-oic acid can obviously inhibit the proliferation of HLC cell line SMMC-7721. The mechanism is correlated with the induction of cell apoptosis by down-regulating the gene expression of bcl-2 gene and up- regulating that of bax gene.

关键词： Annona glabra Linn diterpenes hepatocellular carcinoma apoptosis gene expression

Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network

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science china(Information sciences) 2011年第7期54卷 1471-1480页

作者： XU XiaoRong 1,zhang JianWu 1 & ZHENG BaoYu 2 1 college of Telecommunication Engineering,Hangzhou Dianzi university,Hangzhou 310018,china 2 Institute of Signal Processing and Transmission,nanjing university of Posts and Telecommunications,nanjing 210003,china 1. college of Telecommunication Engineering Hangzhou Dianzi University Hangzhou 310018 China2. Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China

In cognitive radio network (CRN) where primary user (PU) and secondary user (SU) wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels,the interference between PU and SU should be eliminated in order to realize spectrum *** division multiple access (PDMA) that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing (OFDM) is proposed,which benefits from the frequency selectivity of the cognitive channel to form a frequency *** precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference *** and simulation results are presented to prove theoretical *** is shown that,achievable bit rates (ABR) of SU could be achieved with optimal power allocation scheme in ***,it is also verified that,with Vandermonde precoder to form PDMA,SU’s signal-to-noise ratio (SNR) and the target rate of PU could impact the ABR of SU significantly in CRN.

关键词： achievable bit rates (ABR) Vandermonde precoder precoder division multiple access (PDMA) optimal power allocation cognitive radio network (CRN)

A NEW IMPLICIT SCHEME FOR SOLVING 3-D SHALLOW WATER FLOWS

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Journal of Hydrodynamics 2009年第6期21卷 790-798页

作者： zhang Zhuo SONG Zhi-yao LV Guo-nian State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Ocean College Hohai University Nanjing 210098 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210097 China

Based on the improved ADI method, this article proposes an improved implicit finite difference scheme for solving 3-D shallow water flows. The main objective is to design a numerical relation between the horizontal velocity on each layer and the depth-averaged velocity for employing the improved ADI method. With the free surface elevation and the depth-averaged velocity obtained by using essentially 2-D depth-averaged mode, the velocity profiles can be obtained easily and simultaneously. The wind-induced flows, the open channel flows due to the pressure gradient and the tidal flows in coastal waters are simulated, and the results are consistent well with the analytical solution and the field data, which shows that the present implicit scheme is stable and effective, and the established model is practical. Moreover, when only one vertical layer is specified, the present 3-D numerical model is reducea to the 2-D depth-averaged model.

关键词： shallow water equation ADI method wind-induced flow gravity-drived flow tidal flow

A five-fold pig bacterial artificial chromosome library:a resource for positional cloning and physical mapping

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Progress in Natural science:Materials International 2006年第08期16卷 889-892页

作者： LIU Wei, zhang Ying, LIU Zhaoliang, GUO Li, WANG Xiaobo, FEI Jing, FENG Jidong, ZHAO Rui, HU Xiaoxiang and LI Ning (The State Key Laboratory for Agro-Biotechnology, college of Biology, china agricultural university, Beijing 100094, china college of Animal science and Technology, china agricultural university, Beijing 100094, china) [a]The State Key Laboratory for Agno-Biotechnology College of Biology China Agricultural University Beijing China [b]college of Animal science and Technology China Agricultural University Beijing China

A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with HindⅢor BamHⅠthe fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 184320 clones which stored in 480 pieces 384-well plates (20 plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 128 kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10 single-copy genes were screened out and the positive clones were yielded between 1 and 8 with an average of 3.6. Positive superpools were obtained for 32 microsatellite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identifica-

关键词： pig BAC library PCR screening system.

Root Physiological and Morphological Characteristics of Two Rice Cultivars with Different Nitrogen-Use Efficiency

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Pedosphere 2010年第4期20卷 446-455页

作者： FAN Jian-Bo zhang Ya-Li D. TURNER DUAN Yin-Hua WANG Dong-Sheng SHEN Qi-Rong Jiangsu Provincial Key Laboratory for Solid Organic Waste Utilization Nanjing Agricultural University Nanjing 210095(China) college of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 (China) Institute of Soil science Chinese Academy of Sciences Nanjing 210008 (China) School of Resource Management The University of MelbourneVictoria 3010 (Australia)

The variation in nitrogen （N） uptake by rice has been widely studied but differences in rice root morphology that may contribute to this variation are not completely understood. Field and greenhouse experiments were carried out to study N accumulation, root dry weights, total root lengths, root surface areas, and root bleeding rates of two rice cultivars, Elio with low N-use efficiency and Nanguang with high N-use efficiency. Low （1 mmol N L^-1） and high （5 mmol N L^-1） N applications were established in the greenhouse experiment, and the N rates were 0, 120, and 240 kg ha^-1 in the field experiments at Jiangning and Jiangpu farms, nanjing, china. The results showed that the N accumulation, root dry weight, total root length, and root surface area increased with an increase in N application. At the heading stage, N accumulation in the shoots and roots of Nanguang was greater than that of Elio in the field experiments and that of Elio at 5 mmol N L^-1 in the greenhouse experiment. After the heading stage, N accumulation was higher for Nanguang at both 1 and 5 mmol N L^-1 in the greenhouse experiment. The total root length and root surface area were significantly different between the two cultivars. Over the range of the fertilizer application rates, the root lengths of Nanguang at Jiangning Farm were 49%-6170 greater at booting and 26%-39% greater at heading than those of Elio, and at Jiangpu Farm they were 22%-42% and 26%-38% greater, respectively. Nanguang had a greater root bleeding rate than Elio. It was concluded that the N-use efficiency of the two rice cultivars studied depended to a great extent on the root morphological parameters and root physiological characteristics at different growth stages.

关键词： N accumulation root bleeding rate root dry weight root surface area total root length

An Efficient Certificateless Ring Signature Scheme

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Wuhan university Journal of Natural sciences 2008年第5期13卷 567-571页

作者： ZHU Lijun zhang Futai college of Mathematics and Computer science NanjingNormal University Nanjing 210097 Jiangsu China

To overcome the drawbacks such as high computational cost, unreasonable security model and long signature length in existing certificateless ring signature schemes, we propose an efficient certificateless ring signature scheme in this paper. Our construction is inspired by some efficient ID-based ring signature schemes, and uses bilinear pairings as a basic tool. Using a reasonable security model, the unforgeability of the proposed scheme is proven based on the intractability of the computational Diffie-Hellman （CDH） problem. The signature length of the new scheme is only ｜G2｜＋n｜G1｜（｜Gi｜ is the bit length of an element in group Gi, i =1, 2）. Compared with other existing certificateless ring signature schemes, the newly proposed scheme has a shorter signature length and is more efficient and practical.

关键词： certificateless ring signature unforgeability bilinear pairings CDH problem