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Chinese Science Bulletin 2001年第4期46卷 330-333页

作者： CHEN Nengsong, SUN Min, ZHANG Kexin & ZHU YunhaiFaculty of earth sciences, China {2. of Geosciences, Wuhan 430074, China department of earth sciences, the university of hong kong, hong kong sar, China Faculty of earth sciences China University of Geosciences Wuhan China department of earth {2. The University of Hong Kong Hong Kong SAR China

Single-grain zircon U-Pb and amphibole 40Ar-39Ar dating have been conducted on a deformed and metamorphosed diorite in the East Kunlun Orogenic Belt, which intruded into the middle Proterozoic Kuhai Group exposed in the south of Xiangride region, Dulan County, NW Qinghai Province. The zircon gives a concordant U-Pb age of (446.5±9.1) Ma. The amphibole yields Ar plateau age of (488.0±1.2. Ma and an isochronal age of (488.9±5.6) Ma. Age results of both stepwise released Ar and conventional K-Ar analysis are remarkably higher than that of zircon U-Pb, suggesting that the amphibole contains excess argon and the amphibole plateau age cannot be taken as the timing of metamorphism or deformation. The zircon age is interpreted to be crystallization age of the diorite pluton, which suggests that an Early-Paleozoic magmatic zone indeed existed in the East Kunlun Orogenic Belt stretching along the region south to the Golmud, Normuhong and Xiangride.

关键词： East Kunlun Orogenic Belt metadiorite geochronology excess argon.

Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2.01

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Science China earth sciences 2005年第9期48卷 1519-1528页

作者： ZHENG Xiangdong1, CHAN Chuenyu2. CUI hong2. QIN Yu3, CHAN Loyan2. ZHENG Yongguang3 & LEE Yusiang2.1. Chinese Academy of Meteorological sciences, Beijing 100081, China 2. {2.t of Civil and Structural Engineering, hong kong Polytechnic university, Hung Hom, hong kong, China 3. {2.t of Atmospheric sciences, Peking university, Beijing 100871, China 1. Chinese Academy of Meteorological sciences 100081 Beijing China 2. department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China 3. department of Atmospheric sciences Peking University 100871 Beijing China

We analyzed vertical distributions of ozone (O3) in the lower troposphere (< 5 km above ground) at Lin’an (119.75°E, 30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obta... 详细信息

We analyzed vertical distributions of ozone (O3) in the lower troposphere (30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obtained from February 2. to April 13, 2.01. The results showed that the vertical O3 distributions are controlled by metrological conditions and the char- acteristics of O3 profiles are related to those of wet bulb potential temperature and wind field. O3 below 2.km showed that the strongest variability and enhanced O3 mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3 profiles below 5 km can be grouped into 5 categories: (1) peak mixing ratio type, (2. well-mixed type, (3) layered-structure type, (4) episodic pollution type and (5) alti- tudinal increasing type. Vertical distributions of O3 affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern China, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3 at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern China also lead to regional accumulation of O3 and high O3 mixing ratio at Lin’an. Long-range transport of O3 and pollutants from the Pearl River Delta in South China and in-situ O3 formation also resulted in elevated O3 mixing ratios at around 1 km altitudes and layered O3 distribution in the lower troposphere.

关键词： vertical ozone distribution, lower troposphere, Yangtze River Delta, Lin'an.

Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science China earth sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002. China 2. department of Geography and Geology, {2. of hong kong, Pokfulam Road, hong kong, China 1. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of Geography and Geology University of Hong Kong Pokfulam Road Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.

Garnet-bearing Granulite Facies Rock Xenoliths from Late Mesozoic Volcaniclastic Breccia, Xinyang, Henan Province

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 445-451页

作者： ZHENG Jianping, SUN Min, LU Fengxiang, WANG Chunyangand Zhong Zengqiu Faculty of earth {2., China university of Geo{2., Wuhan 430074, China department of earth {2., the university of hong kong, China Faculty of earth sciences China University of Geosciences Wuhan 430074 China department of earth {2. The University of Hong Kong China [?]3Zheng Jianping Born in 1964 graduated from the China university of Geosciences (Wuhan) with a PhD degree in 1997 mainly engaged in teaching and scientific researches on petrology and chemical geodynamics. E-mail: jpzheng@***.

This paper presents the primary results of petrologic, mineralogical and petrochemical studies of garnet-bearing granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe of late Mesozoic volcaniclastic breccia, are of high density (3.13–3.30 g/cm3) and high seismic velocity (Vp = 7.04–7.31 km/s), being products of underplating of basaltic magmas and had experienced granulite facies metamorphism. The underplating and metamorphism took place before the eruption of the host rock. Petrographical studies and equilibrium T-P calculations show that these xenoliths were captured at a 49 km depth and experienced at least a 16 km uplift before they were captured. The dynamics of the uplift could be related to the continent-continent collision between the North China plate and the Yangtze plate during the Triassic.

关键词： granulite facies mafic rock xenolith uplift Xinyang

Analysis of spatio-temporal pattern and driving force of land cover change using multi-temporal remote sensing images

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Science China(Technological sciences) 2010年第S1期53卷 111-119页

作者： ZHOU QiMing & SUN Bo department of Geography,hong {2. Baptist university,hong {2.,China 1. department of Geography Hong Kong Baptist University Hong Kong China

Landuse and land cover change is regarded as a good indicator that represents the impact of human activities on earth’s *** the large collection of multi-temporal satellite images has become available,it is possible to study a long-term historical process of land cover *** study aims to investigate the spatio-temporal pattern and driving force of land cover change in the Pearl River Delta region in southern China,where the rapid development has been witnessed since *** fast economic growth has been associated with an accelerated expansion of urban landuse,which has been recorded by historical remote sensing *** paper reports the method and outcome of the research that attempts to model spatio-temporal pattern of land cover change using multi-temporal satellite *** classified satellite images were compared to detect the change from various landuse types to built-up *** trajectories of land cover change have then been established based on the time-series of the classified land cover *** correlation between the expansion of built-up areas and selected economic data has also been analysed for better understanding on the driving force of the rapid urbanisation *** result shows that,since early 1990s,the dominant trend of land cover change has been from farmland to urban *** relationship between economic growth indicator(measured by GDP)and built-up area can well fit into a linear regression model with correlation coefficients greater than *** is quite clear that cities or towns have been sprawling in general,demonstrating two growth models that were closely related to the economic development stages.

关键词： remote sensing change detection multi-temporal image processing spatio-temporal analysis land cover change Pearl River Delta urban expansion

Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province

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矿物学报 2009年第S1期29卷 314-316页

作者： LI Jian-wei 1,2.DENG Xiao-dong1,2.ZHOU Mei-fu3,LIU Yong-sheng1(1. State Key Laboratory of Geological Processes and Mineral Resources,China university of Geosciences,Wuhan 430074,China 2. Faculty of {2. Resources,China university of Geosciences,Wuhan 430074,China 3. department of {2. sciences,the university of hong kong,hong kong)

Titanite(CaTi2.iO5) is an important accessory mineral not only in magmatic and metamorphic rocks,but also commonly in hydrothermal mineral deposits. It incorporates appreciable amounts(usually 10×10-6 s to 100×10-6 s) of U and Th into its structure and has a closure temperature of Pb diffusion higher than 660～700 ℃(Scott and St-Onge,1995) ,making it an ideal U-Th-Pb geochronometer. The Daye metallogenic district is located in the west of the giant Middle-Lower Yangtze River(MLYR) Cu-Fe-Au province,eastern China and is well endowed with Fe,Cu,and polymetallic skarn deposits.

关键词： Pb Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province Th Fe ICP Cu MS

THE EVOLUTIONARY HISTORY OF THE WEST KUNLUN MOUNTAINS: A TECTONIC RECONSTRUCTION BASED ON STUDIES OF MAGMATISM

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地学前缘 2000年第S1期7卷 262-263页

作者： Yuan Chao 1,2., Sun Min 2. Li Jiliang 3[WT5,5”BX](1 Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640,China 2.department of {2. sciences, the university of hong kong, Pokfulam Road, hong kong, China 3.Institut

The Kunlun Mountains is situated in the north margin of the Tibetan plateau and is one of crucial areas for unraveling the tectonic evolutionary history of the plateau and Eurasia. However, there is no widely accepted model for this area. One of the reasons is that some basic issues for the tectonic reconstruction have not been well settled, they are: (1) Is the Kunlun Mountains an ancient accretion prism, or a mini continent with old basement?(2. What is the age of the Kudi ophiolite, early Paleozoic or late Paleozoic?(3) When did the South Kunlun Block accrete to the Tarim Block?(4) Do the fifth and the forth sutures represent different oceans, or they are just the chronologically different relics of the same ocean?(5) Did the Kunlun Mountains experience continuous subduction since Neoproterozoic?(6) When did the Paleo\|Tethys closed in the West Kunlun range?

关键词： West Kunlun Mountains Proto\|Tethys Paleo\|Tethys boninite series rocks accretion prism magmatic gap tectonic reconstruction

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic {2. and Natural Resources Re-search, Chinese Academy of {2., Beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry {2., Beijing 100091, China 3. department of Civil Engineering, university of hong kong, hong kong, China 4. Eco-environmental Research Center, Chinese Academy of {2., Beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural university, Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Determination of ocean tide loading displacements in hong kong using GPS technique

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Science China earth sciences 2010年第7期53卷 993-1007页

作者： YUAN LinGuo1,3, DING XiaoLi1, SUN HePing2. Zhong Ping1,3 & CHEN Wu1 1 department of Land Surveying and Geo-Informatics, The hong kong Polytechnic university, Kowloon, hong kong, China 2.Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 430077, China 3 department of Surveying Engineering, School of Civil Engineering, Southwest Jiaotong university, Chengdu 610031, China 1. department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic University Kowloon Hong Kong China3. Department of Surveying Engineering School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China2. Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Ocean tide loading (OTL) displacements of eight principal constituents at 12.sites in hong kong were determined using more than eight years of continuous GPS observations. Parameters of the OTL displacements were estimated using daily GPS solutions obtained with precise point positioning (PPP) technique. The results were compared with predictions from seven latest global ocean tide models. Gravity measurements of OTL in hong kong were also used to validate the GPS results. The study shows that the results from both the GPS and gravity measurements agree best with the GOT4.7 and NAO99b models, when the K1 and K2.constituents are excluded. The agreements between the GPS and the model estimates are generally at sub-millimeter level in both the horizontal and vertical directions, except for S2. K2.and K1 constituents that have relatively larger errors. After removing the systematic biases between the GPS and the model estimates, the misfits of M2. S2. N2. O1, P1 and Q1 at all sites are within 0.5 and 1.0 mm in the horizontal and the vertical directions, respectively, whereas K1 and K2.show relatively larger misfits of up to 2.3 mm. Both the GPS and the gravity S2.estimates have large biases with unknown reasons when compared with the modeled values, which needs to be further investigated. The study demonstrates that GPS is capable of estimating the OTL displacements with the same accuracy as the model predictions, especially for coastal areas.

关键词： GPS ocean tide loading ocean tide model site displacement

Restoring cellular calcium homeostasis to rescue ER stress by 1,2.bis(2.aminophenoxy)ethane-N,N,N’,N’-tetraacetic acid acetoxymethyl ester-loaded lipid-mPLGA hybrid-nanoparticles for acute kidney injury therapy

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Chinese Chemical Letters 2024年第3期35卷 337-345页

作者： Jingwen Zhang Jiahui Yan Yanan Wang hong Liu Xueping Sun Yuchao Gu Liangmin Yu Changcheng Li Jun Wu Zhiyu He Frontiers Science Center for Deep Ocean Multispheres and earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Sanya Oceanographic Institution Ocean University of ChinaQingdao 572024China Bioscience and Biomedical Engineering Thrust The Hong Kong University of Science and Technology(Guangzhou)NanshaGuangzhou 511400China Division of Life Science The Hong Kong University of Science and TechnologyHong Kong 999077China

Early pathogenesis of ischemia-reperfusion(I/R)-induced acute kidney injury(AKI)is dominated by intracellular calcium overload,which induces oxidative stress,intracellular energy metabolism disorder,inflammatory activation,and a series of pathologic cascaded reactions that are closely intertwined with self-amplifying and interactive feedback loops,ultimately resulting in cell damage and kidney ***,most nanomedicines originate from the perspective of antioxidant stress,which can only quench existing reactive oxide species(ROS)but cannot prevent the continuous production of ROS,resulting in insufficient *** a safe and promising drug,BAPTA-AM is hydrolyzed into BAPTA by intracellular esterase upon entering cells,which can rapidly chelate with overloaded Ca^(2.),restoring intracellular calcium homeostasis,thus inhibiting ROS regeneration at the ***,we designed a KTP-targeting peptide-modified yolk-shell structure of liposome–poly(ethylene glycol)methyl ether-block-poly(L-lactide-co-glycolic)(mPLGA)hybrid nanoparticles(2.Casp-12.Casp-3)and the inflammatory pathway(TNF-α–NF-κB–IL-6 axes),thus alleviating pathological changes in kidney tissue,thereby inhibiting the expression of renal tubular marker kidney injury mole

关键词： BAPTA-AM Calcium overload Acid-responsive AKI ER stress