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Identification of marine natural gases with different origin sources

Science china Earth sciences 2008年第S1期51卷 148-164页

作者： WANG YunPeng 1 ,zhao ChangYi 2 ,WANG zhaoYun 2 ,WANG HongJun 2 ,TIAN Jin 1 ,ZOU YanRong 1 &LIU JinZhong1 1State Key Laboratory of Organic geochemistry,guangzhou institute of geochemistry,chinese academy of sciences,guangzhou 51064.,china 2institute of Geology,Research institute of Petroleum Exploration and Development,Petrochina,Beijing 100083,china State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China institute of Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083

Kinetic experiments of gas generation for typical samples of marine gas precursors including low-maturity kerogen,residual kerogen and oil as well as dispersed liquid hydrocarbon(DLH)in source rocks were performed by closed system,and the evolution trends of molecular and isotopic compositions of natural gases from different precursors against the maturity(R0%)at laboratory conditions were *** diagrams of gas origin were calibrated by using the experimental data.A diagram based on the ratio of normal and isomerous butane and pentane(i/nC4-i/nC5)was proposed and used to identify the origins of the typical marine natural gases in the Sichuan Basin and the Tarim Basin, *** the maturities of natural gases were estimated by using the statistical relationships between the gaseous molecular carbon isotopic data and maturities(δ13C-R 0 %)with different *** results indicate that the molecular and isotopic compositions of simulated gases from different precursors are different from each *** example,the dryness index of the oil-cracking gas is the lowest;the dryness indices of gases from DLH and kerogen in closed system are almost the same;and the dryness index of gases from residual kerogen is extremely high,indicating that the kerogen gases are very dry;the contents of non-hydrocarbon gases in kerogen-cracking gases are far higher than those in oil-cracking and DLH-cracking *** molecular carbon isotopes of oil-cracking gases are the lightest,those of kerogen in closed system and GLH-cracking gases are the second lightest,and those of cracking gases from residual kerogen are the *** calibration results indicate that the diagrams of ln(C1/C2)-ln(C2/C3)andδ13C2-δ13C3-ln(C2/C3)can discriminate primary and secondary cracking gases,but cannot be used to identify gas origin sources,while the diagram of i/nC4-i/nC5 can differentiate the gases from different *** application results of these diagrams show that gas mixtures ext

关键词： marine organic matter gas origin sources kerogen oil-cracking gas origin identification carbon isotope

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Distribution and identification of the low-velocity layer in the northern South china Sea

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Progress in Natural Science:Materials International 2007年第5期17卷 591-600页

作者： zhao Minghui, Qiu Xuelin, Xu Huilong, Shi Xiaobin, Wu Shimin , Ye Chunming and Xia Shaohong (Key Laboratory of Marginal Sea Geology, South china Sea institute of Oceanology, chinese academy of sciences, guangzhou 510301, china Earthquake Administration of Guangdong Province, guangzhou 510070, china) [a]Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China [b]Earthquake Administration of Guangdong Province Guangzhou China

The low-velocity layer (LVL), closely related with tectonic activities and dynamic settings, has always been a hot topic in the deep crustal structure studies. The deep seismic (OBS/OBH) and onshore-offshore experiments have been extensively implemented in the northern South china Sea (SCS) since the 1990s. Six seismic profiles were finished on the northern margin of SCS by domestic and international cooperations. The features of crustal structures were revealed and five velocity-inversion layers were discovered. Among them three LVLs with 3.0—3. 5 km·s-1 velocity are located in the sedimentary structure (2.0—6.0 km in depth and 2.0—4. 6 km in thickness) of the Yinggehai Basin and Pearl River Mouth Basin. They were identified by the reflective and refractive phases for their shallow depth. The other two LVLs with 5.5—6.0 km·s-1 velocity generally existed in the middle crust (7.0—18.0 km in depth) with an about 2.5—6.0 km thickness in the transitional crustal structure of the northeastern and northwestern SCS. They were detected by the refractive phase from their overlain and underlying layers. We explored the possible tectonic formation mechanisms combining with previously reported results, which provided evidence for the formation and evolution of SCS.

关键词： low-velocity layer deep crustal structure the northern South china Sea OBS/OBH and onshore-offshore seismic experiments.

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Timing of Holocene sea-level highstands by mass spectro-metric U-series ages of a coral reef from Leizhou Peninsula, South china Sea

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chinese Science Bulletin 2002年第4期47卷 348-352页

作者： zhao Jianxin & YU KefuDepartment of Earth sciences, University of Queensland, Brisbane, Qld 4072, Australia (e-mail: j.zhao@earth.uq.edu.au) South china Sea institute of Oceanology, chinese academy of sciences, guangzhou 501301, china (e-mail: kefuyu@scsi Department of Earth sciences University of Queensland 4072 Brisbane QLD Australia South china Sea institute of Oceanology Chinese Academy of Sciences 501301 Guangzhou China

Systematic mass spectrometric 230Th ages are reported for a Ponies coral reef terrace from Dengloujiao, Leizhou Peninsula, South china Sea. Seven episodes of coral growth were recognized in this terrace: 7125±96, 6764±29, 5826±37, 5006±54, 2543±24, 1915±15, and 1513±22 calendar years before present (cal. aBP). 50% of the coral age popula-tion fall between 7200 and 6600 cal. aBP, marking post-glacial stabilization of global sea level. Considering the facts that (i) Dengloujiao reef flat was measured at 1.6-2.5 m above modern tidal datum plane; (ii) modern Parties corals in the South china Sea are living at least ~1 m below the modern tidal datum plane; (iii) the top 20-30 cm of the reef was eroded; and (iv) crustal subsidence in the region since mid-Holocene was negligible, we conclude that the above age groups record at least two major periods (7200-5000 and 2500-1500 cal. aBP) of high sea-level at least 2.9-3.8 m above the present-day level.

关键词： coral South china Sea U-series dating sea level Holo-cene.

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SYNTHESIS AND OPTICAL PROPERTIES OF A NOVEL ORGANIC/INORGANIC HYBRID NONLINEAR OPTICAL POLYMER VIA SOL-GEL PROCESS

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chinese Journal of Polymer Science 2001年第4期19卷 421-427页

作者： Hong-xia Xi Zhong Li zhao-xi Liang The institute of Chemical Engineering South china University guangzhou 51064. china The institute of Polymer Science, Zhongshan University guangzhou 510275, china S china Univ Inst Chem Engn Canton 510640 Peoples R China Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by SEM, FTIR,H-1-NMR, UV-Vis, DSC and second harmonic generation (SHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic SiO2 networks induces low dipole alignment relaxation and preferable orientational stability. The SHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good SHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.

关键词： sol-gel process nonlinear optical material alkoxysilane dye dipole alignment relaxation chromophore

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Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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Science china Earth sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2, YU Haifeng3, YE Haimin2, zhao Yu2 & ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 51064., china 2. Nanjing institute of Geology and Mineral Resources, Nanjing 210016, china 3. Tianjin institute of Geology and Mineral Resources, Tianjin 300170, china 4. The 2nd Regional Geological Investigation Party, Xinjiang Bureau of Geology and Mineral Resources, Changji 831100, china 1. Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 2. Nanjing institute of Geology and Mineral Resources Nanjing 210016 China 3. Tianjin institute of Geology and Mineral Resources Tianjin 300170 China 4. The 2nd Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 831100 China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2DM model ages of 470 to 580 Ma and positive εNd(331 Ma) values of 6.23 to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

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UniBind:a novel artificial intelligence-based prediction model for SARS-CoV-2 infectivity and variant evolution

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Signal Transduction and Targeted Therapy 2024年第1期9卷 14-15页

作者： Qihong Yan Jincun zhao State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory Healththe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouChina

In a recent study published in Nature Medicine,Wang et *** an excellent framework called UniBind based on artificial intelligence(AI),which enables accurately predicting infectivity of SARS-CoV-2 variants and evolutionary trends of future viral variants.1 This computational method holds the possibility to not only serve as a valuable early-warning tool for monitoring potential pathogenic SARS-CoV-2 variants but also facilitate fundamental research on protein-protein interactions(PPIs).

关键词： artificial Bind prediction

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The effect of thermal treatment on the transformation and transportation of arsenic and cadmium in soil

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Journal of Environmental sciences 2024年第11期145卷 205-215页

作者： Fengping Zhou Meina Guo Nan zhao Qianting Xu Tuokun zhao Weihua Zhang Rongliang Qiu Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil RemediationSchool of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Shenzhen Research institute Sun Yat-sen UniversityShenzhen 518057China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South china Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety School of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Ganjiang Innovation academy Chinese Academy of SciencesGanzhou 341000China

Thermal treatment can effectively decontaminate soils but alter their *** research mainly focused on volatile organic compounds andmetals,***,neglecting nonvolatile metal(loid)*** study aimed to investigate Cd and As transformation during aerobic and anaerobic *** results showed that both aerobic and anaerobic calcination increased soil pH by reducing soil organic matter(SOM)content,which also influenced the cation exchange capacity(CEC)and the leaching behavior of Cd and As in the *** total concentrations of Cd and As in the calcined soils varied depending on the calcination temperature and *** the aerobic calcination temperature exceeded 700℃,Cd volatilized as CdCl_(2),while anaerobic calcination at relatively low temperatures(600℃)involved reductive reactions,resulting in the formation of metallic Cd with a lower boiling ***,As volatilized at 800℃aerobically and 600℃*** formation of As-based minerals,particularly Ca3(AsO4)2,hindered its gasification,whereas anaerobic calcination promoted volatilization efficiency through the generation of C-As(III)based gaseous components with lower boiling *** trends were observed in the TCLP-extractable Cd and As contents of the calcined *** 70%of TCLP-extractable Cd contents were suppressed after thermal treatment,attributed to the elevated pH and reduced CEC of the soil,as well as ***,TCLP-extractable As contents increased with elevated temperatures,likely due to the desorption of AsO43−and re-adsorption of gaseous As2O3 during *** findings have implications for assessing the environmental impact of thermal treatment and provide insights for remediation strategies concerning Cd and As-contaminated soils.

关键词： Thermal treatment Soil Cadmium Arsenic Transformation

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Cloning of artemisinin biosynthetic cDNAs and novel ESTs and quantification of low temperature-induced gene overexpression

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Science china(Life sciences) 2008年第3期51卷 232-244页

作者： ZENG QingPing1, zhao Chang1, YIN LuLu1, YANG RuiYi1, ZENG XiaoMei1, HUANG Ying2, FENG LiLing3 & YANG XueQin3 1 Laboratory of Biotechnology, Tropical Medicine institute, guangzhou University of chinese Medicine, guangzhou 510405, china 2 guangzhou General Hospital, guangzhou Military Area Command of chinese PLA, guangzhou 510010, china 3 Center of Artemisinin Research, guangzhou University of chinese Medicine, guangzhou 510405, china 1. Laboratory of Biotechnology Tropical Medicine Institute Guangzhou University of Chinese Medicine Guangzhou 510405 China 2. guangzhou General Hospital Guangzhou Military Area Command of Chinese PLA Guangzhou 510010 China 3. Center of Artemisinin Research Guangzhou University of Chinese Medicine Guangzhou 510405 China

To isolate and verify novel genes from qinghao (Artemisia annua) based on the development-specific and environment-induced transcriptomics, leaves have been harvested from the flowering A. annua plants and exposed to low temperature for isolation of total RNAs and cloning of full-length cDNAs and cDNA fragments, or expressed sequence tags (ESTs). After being sequenced and browsed for homol- ogy, these sequences have been submitted to GenBank. Among the accessed 75 sequences, 4 full-length cDNAs are highly homologous to the known A. annua genes, but 71 ESTs are absent in the sequence records of A. annua genes, in which 34 sequences are homologous to other plant genes, including 24 identified protein-coding sequences and 10 unidentified protein-coding sequences, while other 37 sequences are not present in the sequence records of any plant genes, representing the first cloned plant genes. In order to investigate the responsive patterns of A. annua genes to extreme envi- ronmental stresses, especially low temperature, the expression levels of 3 critical qinhaosu (artemisi- nin) biosynthetic genes, ADS, CYP71AV1 and CPR, have been measured in pre- and post-chilling A. annua seedlings cultured in vitro by semi-quantitative PCR (SQ-PCR). Consequently, ADS and CYP71AV1 genes are strongly induced by chilling, but CPR gene is not significantly affected by such treatment. Furthermore, induction of these genes by chilling can be potently suppressed by Ca2+ channel inhibitor LaCl3 or Ca2+ chelator EGTA, suggesting a putative involvement of Ca2+-CaM signal transduction pathway in chilling-induced overexpression of ADS and CYP71AV1 genes. The real-time fluorescent quantitative PCR (RFQ-PCR) assay of A. annua seedlings exposed to chilling has shown that the expression level of CaM gene is up-regulated for more than 2.5 folds, thereby confirming our above inference on the relevance of Ca2+-CaM-mediated signal transduction to chilling-induced gene overexpression. Finally, 7 newly iso

关键词： Artemisia annua expressed sequence tag (EST) abiotic stress signal transduction fluorescent quantification

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Quantum self-attention neural networks for text classification

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Science china(Information sciences) 2024年第4期67卷 301-313页

作者： Guangxi LI Xuanqiang zhao Xin WANG institute for Quantum Computing Baidu Research Centre for Quantum Software and Information University of Technology Sydney QICI Quantum Information and Computation Initiative Department of Computer ScienceThe University of Hong Kong Thrust of Artificial Intelligence Information HubHong Kong University of Science and Technology(Guangzhou)

An emerging direction of quantum computing is to establish meaningful quantum applications in various fields of artificial intelligence, including natural language processing(NLP). Although some efforts based on syntactic analysis have opened the door to research in quantum NLP(QNLP), limitations such as heavy syntactic preprocessing and syntax-dependent network architecture make them impracticable on larger and real-world data sets. In this paper, we propose a new simple network architecture, called the quantum selfattention neural network(QSANN), which can compensate for these limitations. Specifically, we introduce the self-attention mechanism into quantum neural networks and then utilize a Gaussian projected quantum self-attention serving as a sensible quantum version of self-attention. As a result, QSANN is effective and scalable on larger data sets and has the desirable property of being implementable on near-term quantum devices. In particular, our QSANN outperforms the best existing QNLP model based on syntactic analysis as well as a simple classical self-attention neural network in numerical experiments of text classification tasks on public data sets. We further show that our method exhibits robustness to low-level quantum noises and showcases resilience to quantum neural network architectures.

关键词： quantum neural networks self-attention natural language processing text classification parameterized quantum circuits

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Proactive Resilience Enhancement of Power Systems with Link Transmission Model-based Dynamic Traffic Assignment Among Electric Vehicles

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1320-1330页

作者： Haoyuan Yan Tianyang zhao Zhanglei Guan Energy Electricity Research Center Jinan UniversityGuangzhou 510632China Energy Research institute Nanyang Technological UniversitySingapore IEEE

The rapid development of electric vehicles(EVs)is strengthening the bi-directional interactions between electric power networks(EPNs)and transportation networks(TNs)while providing opportunities to enhance the resilience of power systems towards extreme *** quantify the temporal and spatial flexibility of EVs for charging and discharging,a novel dynamic traffic assignment(DTA)problem is *** DTA problem is based on a link transmission model(LTM)with extended charging links,depicting the interaction between EVs and power *** models the charging rates as continuous variables by an energy boundary *** consider the evacuation requirements of TNs and the uncertainties of traffic conditions,the DTA problem is extended to a two-stage distributionally robust *** is further incorporated into a two-stage distributionally robust unit commitment problem to balance the enhancement of EPNs and the performance of *** problem is reformulated into a mixed-integer linear programming problem and solved by off-the-shelf commercial *** studies are performed on two test *** effectiveness is verified by the numerical results,e.g.,reducing the load shedding amount without increasing the unmet traffic demand.

关键词： Coupled transportation and power network link transmission model resilience enhancement

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