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Lithological Discrimination of the Mafic-Ultramafic Complex, Huitongshan, Beishan, China: Using ASTER Data

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Journal of Earth Science 2014年第3期25卷 529-536页

作者： Lei Liu Jun Zhou Dong Jiang Dafang Zhuang Lamin R Mansaray Key Laboratory of Western Mineral Resources and Geological Engineering of Ministry of Education School of Earth Sciences and Resources Chang'an University Lanzhou AuriferouStone Mining Services Co. Ltd. Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

The Beishan area has more than seventy mafic-ultramafic complexes sparsely distributed in the area and is of a big potential in mineral resources related to mafic-ultramafic intrusions. Many mafic-ultramafic intrusions which are mostly in small sizes have been omitted by previous works. This research takes Huitongshan as the study area, which is a major district for mafic-ultramafic occurrences in Beishan. Advanced spaceborne thermal emission and reflection radiometer（ASTER） data have been processed and interpreted for mapping the mafic-ultramafic complex. ASTER data were processed by different techniques that were selected based on image reflectance and laboratory emissivity spectra. The visible near-infrared（VNIR） and short wave infrared（SWIR） data were transformed using band ratios and minimum noise fraction（MNF）, while the thermal infrared（TIR） data were processed using mafic index（MI） and principal components analysis（PCA）. ASTER band ratios（6/8, 5/4, 2/1） in RGB image and MNF（1, 2, 4） in RGB image were powerful in distinguishing the subtle differences between the various rock units. PCA applied to all five bands of ASTER TIR imagery highlighted marked differences among the mafic rock units and was more effective than the MI in differentiating mafic-ultramafic rocks. Our results were consistent with information derived from local geological maps. Based on the remote sensing results and field inspection, eleven gabbroic intrusions and a pyroxenite occurrence were recognized for the first time. A new geologic map of the Huitongshan area was created by integrating the results of remote sensing, previous geological maps and field inspection. It is concluded that the workflow of ASTER image processing, interpretation and ground inspection has great potential for mafic-ultramafic rocks identifying and relevant mineral targeting in the sparsely vegetated arid region of northwestern China.

关键词： mafic-ultramafic complex ASTER data band ratio minimum noise fraction mafic index principal component analysis.

Biochemical responses of the freshwater microalga Dictyosphaerium sp. upon exposure to three sulfonamides

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Journal of Environmental Sciences 2020年第11期32卷 141-148页

作者： Shan Chen Jiayuan Li Wenbo Feng Mingzhe Yuan Wei Zhang Houtao Xu Xiaoyan Zheng Liqing Wang Centre for research on Environmental Ecology and Fish Nutrient of the Ministry of Agriculture Key Laboratory of Exploration and Utilization of Aquatic Genetic ResourcesMinistry of EducationShanghai Ocean UniversityShanghai 201306China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aquatic Environmental Engineering Co. LtdShanghai 200090China

Sulfonamides(SAs)are common antimicrobial drugs,which are frequently detected in surface water systems,and are difficult to degrade,posing a potential threat to the aquatic ***,little is known about the potential adverse effects of SAs on nontarget organisms(e.g.,microalgae)in the aquatic *** this study,the effect of SAs(sulfadiazine(SD),sulfamerazine(SM1),and sulfamethazine(SM2)at 1,5,20,and 50 mg/L concentrations,respectively)on the freshwater microalga Dictyosphaerium *** investigated,with respect to changes of biomass and chlorophyll a content and induction of extracellular polymer substances(EPS),including protein and polysaccharide *** the same time,the residue of SAs was *** results showed that Dictyosphaerium *** tolerant to the three SAs,and the chlorophyll a content in Dictyosphaerium *** decreased on day 7,followed by a"compensation phenomena".The increase in protein and polysaccharide contents played a defensive role in Dictyosphaerium *** antibiotic stress,and there was a strong positive correlation between polysaccharide contents and antibiotic *** *** 35%–45%,30%–42%,and 26%–51%removal of SD,SM1,and SM2,*** study is helpful to understand the changes of EPS in the defense process of microalgae under the action of antibiotics,and provides a new insight for the ecological removal of antibiotic pollution in natural surface water system.

关键词： Sulfonamides Dictyosphaerium Tolerance Polysaccharide Removal

Adaptive fault diagnosis of sucker rod pump systems based on optimal perceptron and simulation data

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Petroleum Science 2022年第2期19卷 743-760页

作者： Xiao-Xiao Lv Han-Xiang Wang Zhang Xin Yan-Xin Liu Peng-Cheng Zhao College of Mechanical and Electrical Engineering China University of PetroleumQingdao266580China

A highly precise and timely diagnosis technology can help effectively monitor and adjust the sucker rod production system(SRPS)used in oil wells to ensure a safe and efficient *** current diagnosis method is pattern recognition of a dynamometer card(DC)based on feature extraction and *** premise of this method is that the training and target data have the same ***,the training data are collected from a field SRPS with different system parameters designed to adapt to production conditions,which may significantly affect the diagnostic *** address this issue,in this study,an improved model of the sucker rod string(SRS)is derived by adding faultparameter dimensions,with which DCs under 16 working conditions could be *** an adaptive diagnosis method is proposed by taking simulated DCs generated near the working point of the target SRPS as training ***,to further improve the accuracy of the proposed method,the DC features are improved by relative normalization and using additional features of the DC position to increase the distance between different types of *** parameters of the perceptron are optimized to promote its ***,the accuracy and real-time performance of the proposed adaptive diagnosis method are validated using field data.

关键词： Sucker rod pump Dynamometer card Adaptive fault diagnosis Sucker rod dynamics Output metering

Sectorization based pilot reuse for improving net spectral efficiency in the multicell massive MIMO system

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Science China(Information Sciences) 2016年第2期59卷 97-111页

作者： Jiahui LI Limin XIAO Xibin XU Shidong ZHOU State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University

A sectorization method using the uniform circular array(UCA) is proposed to improve the net spectral efficiency(SE) of the multicell massive MIMO system, which is an important index for evaluating the performance of a communication system. We derive the ergodic achievable uplink net SE per cell of a general sectorized system and obtain its deterministic approximation based on the large random matrix *** weight matrices are considered for the sectorized system and the one with the best performance is utilized for further analysis. The consistency of the deterministic approximation with the result of Monte-Carlo simulation is proved at the same time. At last, numerical results indicate that the net SE per cell can be greatly improved compared to the conventional multicell massive MIMO system, which validates the effectiveness of the sectorization method. Moreover, comparisons with other pilot reuse methods are also made in this paper.

关键词： massive MIMO multicell net SE pilot reuse sectorization UCA

Response mechanism of Chlamydomonas reinhardtii to nanoscale bismuth oxyiodide(nano-BiOI):Integrating analysis of mineral nutrient metabolism and metabolomics

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Journal of Environmental Sciences 2022年第11期34卷 13-24页

作者： Yan Huang Jinlong Lai Yang Huang Xuegang Luo Xu Yang Zewei Liu Yue Duan Chen Li School of Life Sciences Southwest University of Science and TechnologyMianyang 621010China College of Environment and Resources Southwest University of Science and TechnologyMianyang 621010China Laboratory of Solid Waste Treatment and Resource Recycle Ministry of EducationMianyang 621010China College of Chemical and Environment Science Shaanxi University of TechnologyHanzhong 723000China

Nanoscale bismuth oxyiodide(nano-BiOI) is widely studied and applied in environmental applications and biomedical fields, with the consequence that it may be deposited into aquatic environments. However, the impact of nano-Bi OI on aquatic ecosystems, especially freshwater microalga, remains limited. Herein, the nano-Bi OI was synthesized and its response mechanism towards microalga Chlamydomonas reinhardtii was evaluated. Results showed that a low concentration of nano-Bi OI(5 mg/L) could stimulate algal growth at the early stage of stress. With the increase in concentration, the growth rate of algal cells was inhibited and showed a dose effect. Intracellular reactive oxygen species(ROS) were significantly induced and accompanied by enhanced lipid peroxidation, decreased nonspecific esterase activity, and significantly upregulated glutathione S-transferase activity(GST) activity. Mineral nutrient metabolism analysis showed that nano-Bi OI significantly interfered with the mineral nutrients of the algae. Non-targeted metabolomics identified 35 different metabolites(DEMs, 22 upregulated, and 13 downregulated) under 100 mg/L Bi OI *** pathway analysis demonstrated that a high concentration of nano-Bi OI significantly induced metabolic pathways related to amino acid biosynthesis, lipid biosynthesis,and glutathione biosynthesis, and significantly inhibited the sterol biosynthesis *** finding will contribute to understanding the toxicological mechanisms of nano-Bi OI on C. reinhardtii.

关键词： Chlamydomonas reinhardtii Nano-BiOI Mineral nutrient Metabolomics

Doppler frequency offset estimation and diversity reception scheme of high-speed railway with multiple antennas on separated carriage

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Journal of Modern Transportation 2012年第4期20卷 227-233页

作者： Yaoqing YANG Pingyi FAN Department of Electronic Engineering Tsinghua University National Mobile Communications research Laboratory Southeast University

The challenges of severe Doppler effects in high-speed railway are considered. By building a cooperative antenna system; an algorithm of joint channel estimation and Doppler frequency offset （DFO） estimation is proposed based on Ricean channel model. First, a maximum likelihood estimation （MLE） algorithm for DFO is designed, show- ing that the Doppler estimation can be obtained by estimating moving velocity of the train and the path loss with the exploitation of pilots that are placed inside the frame. Then a joint detection algorithm for the receiver is proposed to exploit multi-antenna diversity gains. Last, the theoretical Crammer Rao bound （CRB） for joint channel estimation and DFO estimation is derived. The steady performance of the system is confirmed by numerical simulations. In particular, when the Ricean fading channel parameter equals 5 and the velocities of train are 100 m/s and 150 m/s, the estimation variances of DFO are very close to the theoretical results obtained by using CRB. Meanwhile, the corresponding sig- nal to noise ratio loss is less than 1.5 dB when the bit error rate is 10-5 for 16QAM signals.

关键词： Doppler frequency offset (DFO) high-speed railway Ricean channel cooperative antenna system

Regulation by competition:a hidden layer of gene regulatory network

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Frontiers of Electrical and Electronic Engineering in China 2019年第2期7卷 110-121页

作者： Lei Wei Ye Yuan Tao Hu Shuailin Li Tianrun Cheng Jinzhi Lei Zhen Xie Michael Q.Zhang Xiaowo Wang Ministry of Education Key Laboratory of Bioinformatics Center for Synthetic and Systems BiologyDepartment of AutomationTsinghua UniversityBeijing 100084China Beijing National research Center for Information Science and Technology Beijing 100084China School of Life Sciences Tsinghua UniversityBeijing 100084China Zhou Pei-Yuan Center for Applied Mathematics Tsinghua UniversityBeijing 100084China Department of Basic Medical Sciences School of MedicineTsinghua UniversityBeijing 100084China Department of Biological Sciences Center for Systems BiologyThe University of TexasRichardsonTX 75080-3021USA

Background:Molecular competition brings about trade-offs of shared limited resources among the cellular components,and thus introduces a hidden layer of regulatory mechanism by connecting components even without direct physical *** molecular competition scenarios have been observed recently,but there is still a lack of systematic quantitative understanding to reveal the essence of molecular ***:Here,by abstracting the analogous competition mechanism behind diverse molecular systems,we built a unified coarse-grained competition motif model to systematically integrate experimental evidences in these processes and analyzed general properties shared behind them from steady-state behavior to dynamic ***:We could predict in what molecular environments competition would reveal threshold behavior or display a negative linear *** quantified how competition can shape regulator-target dose-response curve,modulate dynamic response speed,control target expression noise,and introduce correlated fluctuations between ***:This work uncovered the complexity and generality of molecular competition effect as a hidden layer of gene regulatory network,and therefore provided a unified insight and a theoretical framework to understand and employ competition in both natural and synthetic systems.

关键词： systems biology computational modeling molecular competition regulation synthetic biology network motif

Boosting Circularly Polarized Luminescence of Organic Conjugated Systems via Twisted Intramolecular Charge Transfer

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research 2020年第1期2020卷 593-602页

作者： Junfeng Li Chenxi Hou Chao Huang Shanqi Xu Xuelei Peng Qi Qi Wen-Yong Lai Wei Huang Key Laboratory for Organic Electronics and Information Displays Institute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi’an710072 ShaanxiChina

Realizing a high luminescence dissymmetry factor(g_(lum))is a paramount yet challenging issue in the research field of circularly polarized luminescence(CPL).Here,we reported a novel set of organic conjugated systems with twisted intramolecular charge transfer(TICT)characteristics based on conjugated o-carborane-binaphthyl dyads composing of binaphthyl units as chiral electron donors and o-carborane units as achiral electron acceptors,demonstrating intense CPL with large g_(lum) ***,single-crystalline o-1 exhibited a high-level brightness and a large g_(lum) factor as high as+0.13,whereas singlecrystalline o-2 processed a relatively low brightness with a decreased g_(lum) value *** significant diversity of CPL-active properties was triggered by the selective introduction of o-carborane units onto the binaphthyl *** from the large magnetic dipole transition moments in TICT states,the CPL activity of TICT o-carborane-based materials exhibited amplified circular *** study provides an efficient molecular engineering strategy for the rational design and development of highly efficient CPL-active materials.

关键词： materials circular conjugated

Efficacy of hepatic resection vs transarterial chemoembolization for solitary huge hepatocellular carcinoma

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World Journal of Gastroenterology 2015年第32期21卷 9630-9637页

作者： Shao-Liang Zhu Jian-Hong Zhong Yang Ke Liang Ma Xue-Mei You Le-Qun Li Department of Hepatobiliary Surgery Affiliated Tumor Hospital of Guangxi Medical University Department of Hepatobiliary Surgery the Second Affiliated Hospital of Kunming Medical University

AIM: To compare the efficacy of hepatic resection(HR) and transarterial chemoembolization(TACE) for patients with solitary huge(≥ 10 cm) hepatocellular carcinoma(HCC).METHODS: Records were retrospectively analyzed of 247 patients with solitary huge HCC, comprising 180 treated by HR and 67 by TACE. Long-term overall survival(OS) was compared between the two groups using the Kaplan-Meier method, and independent predictors of survival were identified by multivariate analysis. These analyses were performed using all patients in both groups and/or 61 pairs of propensity score-matched patients from the two groups. RESULTS: OS at 5 years was significantly higher in the HR group than the TACE group, across all patients(P = 0.002) and across propensity score-matchedpairs(36.4% vs 18.2%, P = 0.039). The two groups showed similar postoperative mortality and morbidity. Multivariate analysis identified alpha-fetoprotein ≥ 400 ng/m L, presence of vascular invasion and TACE treatment as independent predictors of poor ***: Our findings suggest that HR can be safe and more effective than TACE for patients with solitary huge HCC.

关键词： Hepatic resection Transarterial chemoembolization