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1Zircon U-Pb geochronological framework of Qitianling granite batholith, middle part of Nanling Range, South China显示文摘The Qitianling granite batholith (QGB) is located in the southern Hunan Province, middle part of the Nanling Range, South China. Its total exposure area is about 520 km2. Based on our 25 single grain zircon U-Pb age data and 7 published data as well as the geological, petrological, and space distribution characteristics, we conclude that QGB is an Early Yanshanian (Jurassic) multi-staged composite pluton. Its formation process can be subdivided into three major stages. The first stage, emplaced at 163―160 Ma with a peak at about 161 Ma, is mainly composed of hornblende-biotite monzonitic granites and locally biotite granites, and distributed in the eastern, northern, and western peripheral parts of the pluton. The second stage, emplaced at 157―153 Ma with a peak at 157―156 Ma, is mainly composed of biotite granites and locally containing hornblende, and distributed in the middle and southeastern parts of the pluton. The third stage, emplaced at 150―146 Ma with a peak at about 149 Ma, is mainly composed of fine-grained (locally porphyritic) biotite granites, and distributed in the middle-southern part of the pluton. Each stage can be further disintegrated into several granite bodies. The first two intrusive stages comprise the major phase of QGB, and the third intrusive stage comprises the additional phase. Many second stage fine-grained granite bosses and dykes intruded into the first stage host granites with clear chilling margin-baking phenomena at their intrusive contacts. They were emplaced in the open fracture space of the earlier stage consolidated rocks. Their isotopic ages are mostly 2―6 Ma younger than their hosts. Conceivably, the time interval from magma emplacement, through cooling, crystallization, solidification, up to fracturing of the earlier stage granites cannot exceed 2―6 Ma. During the Middle-Late Jurassic in the Qitianling area and neighboring Nanling Range, the coeval granitic and basic-intermediate magmatic activities were widely developed. It indicates that the Early Yanshanian period was the culmination time of magmatic activities in this region. The Nanling Range was under a post-orogenic, intracontinental geotectonic environment with an obvious lithospheric extension and thinning. The crust-mantle interaction played an important role in formation of granitic rocks in this region.ZHU JinChu WANG RuCheng ZHANG PeiHua XIE CaiFu ZHANG WenLan ZHAO KuiDong XIE Lei YANG Ce CHE XuDong YU APeng WANG LuBin 2009Science China Earth Sciences2009,52,9:27
2Metallogenesis related to Mesozoic Granitoids in the Nanling Range, South China and Their Geodynamic Settings显示文摘Affected by the compressive stress from the South-Central (Indo-China) Peninsula, the Indosinianorogenesis, characterized by collision, thrust and uplifting, took place inside the South China Plate during 250?230 Ma.The ages of the Indosinian granitoids in the Nanling Range and vicinity areas are mostly 240?205 Ma, indicating that theywere emplaced in both late collision and post-collision geodynamic environments. No important granite-relatedmetallogenesis occurred in this duration. A post-orogenic setting started at the beginning of the Yanshanian Period, whichcontrolled large-scale granitic magmatism and related metallogenesis. This paper makes the first attempt to divide theYanshanian Period into three sub-periods, i.e. the early, middle and late Yanshanian Periods, based mainly on the featuresof magmatism, especially granitoids and related metallogenesis and their geodynamic environments. The magmaticassociation of the Early Yanshanian (about 185?170 Ma) comprises four categories of magmatism, i.e. basalt, bimodalvolcanics, A-type granite and intraplate high-K calc-alkaline (HKCA) magmatism, which indicates an extension-thinningof lithosphere and upwelling of mantle material to a relative small and local extent. Pb-Zn, Cu and Au mineralizationsassociated with HKCA magmatism represents the first high tide of Mesozoic metallogenesis in the Nanling Range area.During the middle Yanshanian, the lithosphere was subjected to more extensive and intensive extending and thinning, andhence mantle upwelling and basaltic magma underplating caused a great amount of crust remelting granitoids. This periodcan be further divided into two stages. The first stage (170?150 Ma) is represented by large-scale emplacement of crustremelting granites with local tungsten mineralization at its end. The second stage (150?140 Ma) is the most important timeof large-scale mineralizations of non-ferrous and rare metals, e.g. W, Sn, Nb-Ta, Bi, Mo, Be, in the Nanling Range area.The late Yanshanian (140?65 Ma) was generally characterized by full extension and breakup of the lithosphere of SouthChina. However, owing to the influence of the Pacific Plate movement, the eastern part of South China was predominatedby subduction-related compression, which resulted in magmatism of calc-alkaline and shoshonite series and relatedmetallogeneses of Au, Ag, Pb-Zn, Cu and (Mo, Sn), followed by extension in its late stage. In the Nanling Range area, thelate Yanshanian magmatism was represented by granitic volcanic-intrusive complexes and mafic dikes, which aregenetically related to volcanic-type uranium and porphyry tin deposits, and the mobilization-mineralization of uraniumfrom pre-existing Indosinian granites.HUA Renmin CHEN Peirong ZHANG Wenlan YAO Junming LIN Jinfu ZHANG Zhanshi GU Shengyan LIU Xiaodong QI Huawen 2005Acta Geologica Sinica(English Edition)2005,79,6:22
3Zircon U-Pb dating confirms existence of a Caledonian scheelite-bearing aplitic vein in the Penggongmiao granite batholith, South Hunan显示文摘Granite at Penggongmiao is a large batholith in the Nanling Range, with an outcrop area of over 900 km 2 . There are many scheelite-quartz veins around the granite. LA-ICP-MS U-Pb dating was carried out for zircons from the granite. The middlecoarse-grained biotite granite has U-Pb ages of 435 to 436 Ma. Ages of 426.5±2.5 Ma were obtained for aplitic dyke cross-cutting the granite. The scheelite of magmatic origin in the aplite dyke was identified from petrographic investigation. This demonstrates that W-bearing granites of Early Paleozoic (corresponding to the Caledonian orogensis in the traditional sense) occur in the Nanling Range. This finding has important implications for the ore-forming potential of Paleozoic granites and on the extent of Mesozoic mineralization. Thus it merits performing an intensive study of Paleozoic granites in South China. The occurrences of aplite or microgranite may be an indicative of the Caledonian tungsten granites and associated W mineralization.ZHANG WenLan WANG RuCheng LEI ZeHeng HUA RenMin ZHU JinChu LU JianJun XIE Lei CHE XueDong ZHANG RongQing YAO Yuan CHEN Jun 2011Chinese Science Bulletin2011,56,19:23
4Skarn-type tungsten mineralization associated with the Caledonian(Silurian) Niutangjie granite, northern Guangxi, China显示文摘The Niutangjie tungsten deposit is a bedded skarn-type scheelite deposit and is located at the junction between Ziyuan and Xingan counties in the north of Guangxi,China.The deposit is genetically related to a fine-grained two-mica granite within the orefield.Zircon LA-ICP-MS U-Pb dating of the granite yielded a Silurian(Caledonian)age of 421.8±2.4 Ma,which is contemporaneous with the adjacent Yuechengling batholith.Mineralization within the skarn is associated with a quartz,garnet,and diopside gangue,and scheelite is present in a number of different mineral assemblages,such as quartz-scheelite and quartz-sulfide-scheelite;these assemblages correspond to oxide and sulfide stages of mineralization.Sm-Nd isotope analysis of scheelite yielded an isochron age of 421±24 Ma.Although the uncertainty on this date is high,this age suggests that the scheelite mineralization formed during the Late Caledonian,at a similar time to the emplacement of the Niutangjie granite.Zircons within the granite have?Hf(t)values and Hf two-stage model ages of?6.5 to?11.6,and 1.79 to 2.11 Ga,respectively.These data suggest that the magma that formed the granite was derived from Mesoproterozoic crustal materials.Scheelite?Nd(t)values range from?13.06 to?13.26,also indicative of derivation from ancient crustal materials.Recent research has identified Caledonian magmatism in the western Nanling Range,indicating that this magmatism may be the source of contemporaneous tungsten mineralization.YANG Zhen WANG RuCheng ZHANG WenLan CHU ZhuYin CHEN Jun ZHU JinChu ZHANG RongQing 2014Science China Earth Sciences2014,57,7:11
5Using Fuzzy Relations and GIS Method to Evaluate Debris Flow Hazard显示文摘The study area,located in the southeast of Tibet along the Sichuan-Tibet highway,is a part of Palongzangbu River basin where mountain hazards take place frequently.On the ground of field surveying,historical data and previous research,a total of 31 debris flow gullies are identified in the study area and 5 factors are chosen as main parameters for evaluating the hazard of debris flows in this study.Spatial analyst functions of geographic information system (GIS) are utilized to produce debris flow inventory and parameter maps.All data are built into a spatial database for evaluating debris flow hazard.Integrated with GIS techniques,the fuzzy relation method is used to calculate the strength of relationship between debris flow inventory and parameters of the database.With this methodology,a hazard map of debris flows is produced.According to this map,6.6% of the study area is classified as very high hazard,7.3% as high hazard,8.4% as moderate hazard,32.1% as low hazard and 45.6% as very low hazard or non-hazard areas.After validating the results,this methodology is ultimately confirmed to be available.SONG Shujun ZHANG Baolei FENG Wenlan ZHOU Wancun 2006Wuhan University Journal of Natural Sciences2006,11,4:10
6Primary Sn-rich titianite in the Qitianling granite, Hunan Province, southern China: An important type of tin-bearing mineral and its implications for tin exploration显示文摘The Qitianling calc-alkaline granite in Hunan Province (South China) has attracted much attention since the discovery of the Furong super-large tin deposit. The present study provides new mineralogical data to address their implications for exploration of tin deposits. In the Taoxiwo granite in the southeastern part of the Qitianling granite body, Sn-rich titanite was identified as an important type of Sn-bearing mineral. The titanite commonly occurs with biotite as euhedral crystals, exhibiting typical envelope-like shape and sector-zoning texture. These indicate that the titanite most likely crystallized in the mag-matic stage. Electron-microprobe analyses show that the titanite is enriched in tin up to 1.12 wt% SnO2, with an average of 0.43 wt%. With the crystallization of the granite, primary minerals undertook hydro-thermal alteration by magma-derived fluids. Subsequently, in the hydrothermal stage, the primary Sn-bearing titanite was altered (at least partially), but still preserved its typical envelope-shaped outline. Micro-scale cassiterite is a representative product of such alteration; other secondary minerals include fluorite, ilmenite, Sn-bearing rutile and quartz. Therefore, the titanite, commonly present in the calc- alkaline granites, can be treated as an important Sn-carrying mineral in the Qitianling granite, reflecting the primary magmatic environment with tin enrichment. The hydrothermal alteration of the primary titanite and subsequent crystallization of cassiterite recorded a process of leaching and accumulation of tin in magmatic-hydrothermal evolution of the Snbearing granite. Thus, this titanite has important implications for tin exploration.XIE Lei WANG RuCheng CHEN Jun ZHU JinChu ZHANG WenLan WANG DeZi YU APeng 2009Chinese Science Bulletin2009,54,5:10
7Evaluation of Two Momentum Control Variable Schemes and Their Impact on the Variational Assimilation of Radar Wind Data:Case Study of a Squall Line显示文摘Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state.Based on the WRF model's three-dimensional variational assimilation system,this study compares the behavior of two momentum control variable options—streamfunction velocity potential(ψ–χ) and horizontal wind components(U–V)—in radar wind data assimilation for a squall line case that occurred in Jiangsu Province on 24 August 2014.The wind increment from the single observation test shows that the ψ–χ control variable scheme produces negative increments in the neighborhood around the observation point because streamfunction and velocity potential preserve integrals of velocity.On the contrary,the U–V control variable scheme objectively reflects the information of the observation itself.Furthermore,radial velocity data from 17 Doppler radars in eastern China are assimilated.As compared to the impact of conventional observation,the assimilation of radar radial velocity based on the U–V control variable scheme significantly improves the mesoscale dynamic field in the initial condition.The enhanced low-level jet stream,water vapor convergence and low-level wind shear result in better squall line forecasting.However,the ψ–χ control variable scheme generates a discontinuous wind field and unrealistic convergence/divergence in the analyzed field,which lead to a degraded precipitation forecast.Xin LI Mingjian ZENG Yuan WANG Wenlan WANG Haiying WU Haixia MEI 2016Advances in Atmospheric Sciences2016,33,10:10
8A study on the Dushiling tungsten-copper deposit in the Miao'ershan-Yuechengling area, Northern Guangxi, China:Implications for variations in the mineralization of multi-aged composite granite plutons显示文摘The polymetallic Dushiling W-Cu deposit is a large, altered, skarn-type deposit, located in the northeastern part of the Miao'ershan-Yuechengling pluton, China. Two types of granite have been identified in the deposit: a medium-grained porphyritic biotite granite, and a medium- to fine-grained biotite granite. Both are spatially and temporally related to ore bodies, suggesting they may be the source of mineralization in the deposit. A medium- to fine-grained porphyritic biotite granite is exposed at the surface in the region of mineralization. U-Pb dating of zircons yielded magmatic ages of 423 Ma for the medium-grained porphyritic biotite granite and 421 Ma for the medium- to fine-grained porphyritic biotite granite, while a younger age(217 Ma) obtained for surface samples indicates later diagenesis. Thus, magmatism occurred during the Caledonian and Indosinian, respectively. The petrological and geochemical characteristics of the two Caledonian granites show that both are calc-alkaline and peraluminous.They are moderately enriched in Cs, Rb, U, and REE, and strongly depleted in Sr,Ba,P,and Ti; they show similar REE behavior,including negative Eu anomalies. These geochemical similarities suggest that the two granites were derived from the same source,although they were emplaced during different stages of the evolution of the magma. Furthermore, the granites are associated with mineralization, suggesting they were the source of mineralization in the Dushiling W-Cu deposit. Sm-Nd ages of scheelite from the Dushiling W-Cu deposit indicate that metallogenesis occurred at 417±35 Ma, while the two types of titanite, intergrown with scheelite, yield U-Pb ages of 423–425 Ma(in altered granite sample) and 218 Ma(in skarn sample). These ages place the main mineralization event in the late Caledonian, and later magmatic-hydrothermal activity occurred in the Indosinian. The ages obtained for the Dushiling W-Cu deposit in the western Nanling Range, northern Yuechengling, together with the occurrence and ages of the Niutangjie W deposit in southern Yuechengling, provide insight into the process of ore concentration during the Caledonian and Indosinian.CHEN WenDi ZHANG WenLan WANG RuCheng CHU ZhuYin XIAO Rong ZHANG Di CHE XuDong 2016Science China Earth Sciences2016,59,11:10
9Genome-Wide Analysis and Expression Patterns of the YUCCA Genes in Maize显示文摘Auxin plays important roles in various aspects of plant growth and development(Zhao,2010).In Arabidopsis,a number of YUCCA(YUC)genes,which are involved in auxin biosynthesis,have been identified(Zhao et al.,2001;Woodward et al.,2005;Cheng et al.,2006,2007;Kim et al.,2007;Chen et al.,2014).YUC genes encode flavin monooxygenases(FMOs)that convert indole-3-pyruvate(IPA)to indole-3-acetic acid(IAA)(Zhao,2012).The Arabidopsis YUC family is comprised of 11 members(Zhao et al.,2001;Wenlan Li Xiangyu Zhao Xiansheng Zhang 2015Journal of Genetics and Genomics2015,42,12:8
10Protective effect of Yiguanjian decoction against DNA damage on concanavalin A-induced liver injury mice model显示文摘OBJECTIVE:To investigate the inhibitory effect of Yiguanjian decoction(YD) on DNA damage in Concanavalin A(Con A)-induced liver injury mice model and to explain the possible mechanism.METHODS:Totally 120 male BALB/c mice were randomly divided into 6 groups,20 mice each:normal group,model group,Bifendate group,YD low dose group,YD middle dose group and YD high dose group.Except normal group,liver injury model induced by Con A was established.While modeling,each mouse in YD group was given YD(0.4 m L/20 g per day) by intragastric administration(0.13 g YD for YD low dose group;0.26 g for YD middle dose group;0.52 g for YD high dose group).Bifendate group was given Bifendate(0.2 gnd model·kg-1 grou·d-1) by gavage.Normal group ap were fed with same volume of physiological saline daily.After 8 weeks,the serum alanine transaminase(ALT)and aspartate transaminase(AST) were tested.The hematoxylin-eosin staining was used to evaluate the grade of liver inflammation and liver fibrosis stage.Hepatocellular DNA damage was detected by single cell gel electrophoresis technology.The protein expression of tumor necrosis factor-α(TNF-α),Bax and Mut T Homolog 1(MTH1) was detected by western blotting and enzyme linked immunosorbent assay.Bax m RNA and MTH1 m RNA were detected by Real-time Polymerase Chain Reaction(PCR).RESULTS:YD can improve the degree of liver inflammation and fibrosis in the liver of chronic hepatitis mice,the dose effect relationship is remarkable(P < 0.05).YD can reduce liver cell DNA damage.The difference between YD middle dose group and model group was statistically significant(P < 0.05).YD middle dose group had decreased the protein expression of TNF-α in the mice liver of immunological liver injury(P < 0.05).YD can increase the protein expression of Bax(P < 0.05).Compared with normal group,the protein expression of MTH1 was decreased(P < 0.05),but there was no statistical significance between YD group and model group(P >0.05).YD can increase the m RNA expression of Bax and MTH1(both P < 0.05).CONCLUSION:YD can effectively inhibit the DNA damage in immunological liver injury mice,the mechanism may be that it can decrease the TNF-αand increase the Bax and MTH1 expression.Tian Mengxi Liu Wenlan You Hongjie Zhao Qingzhou Ouyang Luodan Gao Biane Zhang Xin Che Niancong 2016Journal of Traditional Chinese Medicine2016,36,4:7
11Design and analysis of a truss deployable antenna mechanism based on a 3UU-3URU unit显示文摘Space deployable structures with large calibers, high accuracy, and large folding ratios are indispensable equipment in the aerospace field. Given that the single-DOF 3 RR-3 RRR deployable unit cannot be fully folded, this study proposes a 3 UU-3 URU deployable unit with two kinds of DOF: folding movement and orientation adjustment. First, based on the G-K formula, the DOF of the 3 UU-3 URU unit is analyzed. Then, the 3 UU-3 URU unit is used to construct a deployable truss antenna with a curved surface, and the DOF of the whole deployable antenna containing multiple 3 UU-3 URU units is calculated. The structural design of a deployable antenna with two loops is carried out with specific parameters and geometric relations. Next, a DOF simulation of a basic combination unit composed of three 3 UU-3 URU units is performed. Finally, a prototype of the basic combination unit is manufactured, and the DOF of the mechanism is experimentally verified.Yundou XU Jinwei GUO Luyao GUO Wenlan LIU Jiantao YAO Yongsheng ZHAO 2019Chinese Journal of Aeronautics2019,32,12:7
12Morphologic characteristics and growth interface stability of nano-micron FeS_2 whiskers显示文摘Micromorphology is further studied on the basis of our previous researches concerned with the nano-micron FeS2 whisker. There are obvious differences in the intensive degree, diameter and micromorphology among the FeS2 whiskers growing in different stages. From the early to late stage, the intensive degree increases, the diameter decreases, and the surface micro-morphology changes following the regularity: protrusive nodulation → coarse → smooth → flat. According to the theory of crystal growth, the geological setting and processes of whisker formation, we discuss the stability and evolution of crystal growth interface of FeS2 whisker occurring in Gengzhuang gold deposit (Shanxi Province, China). The results suggest that the negative temperature gradient and the supercooling appear in the early stage of the whisker growth, whereas the positive temperature gradient of reposeful state appears in the late stage. In the whisker growth stage, the component concentration changes through the three stages: severely nonhomogeneous in the early stage, relatively homogeneous in the middle stage, more homogeneous in the late stage. The general changing process of the interfacial state is from unstable to stable. Micromorphology of FeS2 whisker in Gengzhuang is the result of synergism of temperature, component concentration and stability of crystal interface phase in hydrothermal system. The micromorphology not only reflects the physical and chemical characteristics of the hydrothermal system during the whisker growth, but also indicates the stability characteristics of the interface phase and records the changing process of the whisker growth.HUANG Fei WANG RuCheng ZHANG WenLan YAO YuZeng PENG YanDong KOU DaMing 2009Chinese Science Bulletin2009,54,23:6
13Thermodynamic evolution of lithosphere of the North China craton:Records from lower crust and upper mantle xenoliths from Hannuoba显示文摘Major element compositions of garnet, clino-pyroxene, orthopyroxene and spinel in the garnet-bearing lower crust and upper mantle xenoliths from Hannuoba, North China craton are analyzed by the electron microprobe (EMP). The pressure-temperature estimates reveal the in-creasing temperature and pressure from core to rim for granulites. In contrast, mantle xenoliths with core tempera-ture > 930℃ recorded a history of decrease in temperature and pressure. However, those with core temperature < 930℃ show a negligible change. The final pressures recorded by these xenoliths cluster at 0.9—1.5 GPa. The presence of high- Na2O cpx in granulite xenoliths suggests that they are prod-ucts of the transition from granulite to eclogite metamor-phism corresponding to the increasing temperature and pressure. Together with previous studies, it is suggested that the P-T changes preserved in the xenoliths are related to lithospheric thickening and subsequent thinning prior to their eruption in the Cenozoic.LIU Yongsheng GAO Shan LIU Xiaoming CHEN Xiaoming ZHANG Wenlan WANG Xuance 2003Chinese Science Bulletin2003,48,21:6
14THE PLANNING AND MANAGEMENT INFORMATION SYSTEM FOR SMALL TOWN (TOWNMIS)——A CASE STUDY AT XIAOLAN TOWN, SOUTH CHINA显示文摘Now, GISs are popular at most major cities along the coast in China. The lack of available digital geographic data is a serious bottleneck problem. This article first analyses the development characteristics of urban planning and management information system in China, and proposes a method for establishing a planning and management information system for small town. By using GIS as core and integrating with microcomputer network, office automation (OA), computer aided design (CAD), and multimedia technology, a microcomputer information system (TownMIS) is implemented after 3 year design and development. It may be a first comprehensive system for the planning and management of small towns. Since the January of 1996, TownMIS has been actually used in Xiaolan Town, a coastal rich town in South China. This has provided perfect technical, managerial, operational and institutional references for resolving the contradiction of the fast growing installation of GIS sites and fewer actually running system.Chen Shunqing State Key Lab. of Resources & Environment Information System Institute of Geography, CAS, Beijing 100101, P. R. ChinaHuang Ling Ge Wenlan Urban Planning Automation Center Guangzhou Urban Planning Bureau, Guangzhou 510030, P. R. China 1997Journal of Geographical Sciences1997,7,1:5
15Application of microwave vegetation index in drought monitoring显示文摘WANG Yongqian SHI Jiancheng LIU Zhihong FENG Wenlan QIU Yubao 2014遥感学报2014,18,4:4
16Assessment and Risk Zonation of Landslides in Panxi Area Based on 3S Technology显示文摘Based on field survey located by GPS, it is obtained landslides’ location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce landslides such as the elevation,the slope, the vegetation cover,the lithology,the rainfall and so on are gained using GIS(geographical information system) techniques of spatial analysis. All the data obtained are managed through building landslide management system. At the same time,the system is made the platform to appraise the relationship between the distribution of landslides and the environmental factors. The results indicate: landslides take place relatively easily in the slope range between 10° and 25°; most landslides are in the mixed area of bush and grass with a coverage degree of from 20% to 65%; the distribution of landslides has a positive relationship with the distribution of annual rainfall. The risk degree of Panxi Area is zoned and mapped by the model of liner stack using GIS technique,and the result indicates: the place of high risk degree is the belt of Panzhihua-Miyi-Dechang-Mugu and southeast of Huili county and Huidong county,and area is about 512 707 hm 2 .ZHANG Baolei SONG Shujun FENG Wenlan ZHOU Wancun 2006Wuhan University Journal of Natural Sciences2006,11,4:3
17A New Potential Caledonian–Indosinian Ore Concentration Area:Evidence from Diagenesis and Mineralization Ages of the Miao'ershan–Yuechengling Region显示文摘Objective The Miao’ershan–Yuechengling composite granite,located in northern Guangxi at the western section of the Nanling Range,is a multi-period and multi-stage composite pluton with an exposed area of more than 3000km2(Fig.1).Paleozoic and Proterozoic strata are exposed around it,and magmatic activities mainly occurredZHANG Wenlan CHE Xudong CHEN Wendi WANG Rucheng ZHANG Di 2017Acta Geologica Sinica(English Edition)2017,91,2:3
18Theoretical and Experimental Research on Error Analysis and Optimization of Tool Path in Fabricating Aspheric Compound Eyes by Precision Micro Milling显示文摘Structure design and fabricating methods of three-dimensional(3D)artificial spherical compound eyes have been researched by many scholars.Micro-nano optical manufacturing is mostly used to process 3D artificial compound eyes.However,spherical optical compound eyes are less at optical performance than the eyes of insects,and it is difficult to further improve the imaging quality of compound eyes by means of micro-nano optical manufacturing.In this research,nonhomogeneous aspheric compound eyes(ACEs)are designed and fabricated.The nonhomogeneous aspheric structure is applied to calibrate the spherical aberration.Micro milling with advantages in processing three-dimensional micro structures is adopted to manufacture ACEs.In order to obtain ACEs with high imaging quality,the tool paths are optimized by analyzing the influence factors consisting of interpolation allowable error,scallop height and tool path pattern.In the experiments,two kinds of ACEs are manufactured by micro-milling with different too path patterns and cutting parameter on the miniature precision five-axis milling machine tool.The experimental results indicate that the ACEs of high surface quality can be achieved by circularly milling small micro-lens individually with changeable cutting depth.A prototype of the aspheric compound eye(ACE)with surface roughness(Ra)below 0.12?m is obtained with good imaging performance.This research ameliorates the imaging quality of 3D artificial compound eyes,and the proposed method of micro-milling can improve surface processing quality of compound eyes.CHEN Mingjun XIAO Yong TIAN Wenlan WU Chunya CHU Xin 2014Chinese Journal of Mechanical Engineering2014,27,3:3
19Physical statistical algorithm for precipitable water vapor inversion on land surface based on multi-source remotely sensed data显示文摘Water vapor plays a crucial role in atmospheric processes that act over a wide range of temporal and spatial scales, from global climate to micrometeorology. The determination of water vapor distribution in the atmosphere and its changing pattern is very important. Although atmospheric scientists have developed a variety of means to measure precipitable water vapor(PWV) using remote sensing data that have been widely used, there are some limitations in using one kind satellite measurements for PWV retrieval over land. In this paper, a new algorithm is proposed for retrieving PWV over land by combining different kinds of remote sensing data and it would work well under the cloud weather conditions. The PWV retrieval algorithm based on near infrared data is more suitable to clear sky conditions with high precision. The 23.5 GHz microwave remote sensing data is sensitive to water vapor and powerful in cloud-covered areas because of its longer wavelengths that permit viewing into and through the atmosphere. Therefore, the PWV retrieval results from near infrared data and the indices combined by microwave bands remote sensing data which are sensitive to water vapor will be regressed to generate the equation for PWV retrieval under cloud covered areas. The algorithm developed in this paper has the potential to detect PWV under all weather conditions and makes an excellent complement to PWV retrieved by near infrared data. Different types of surface exert different depolarization effects on surface emissions, which would increase the complexity of the algorithm. In this paper, MODIS surface classification data was used to consider this influence. Compared with the GPS results, the root mean square error of our algorithm is 8 mm for cloud covered area. Regional consistency was found between the results from MODIS and our algorithm. Our algorithm can yield reasonable results on the surfaces covered by cloud where MODIS cannot be used to retrieve PWV.WANG YongQian SHI JianCheng WANG Hao FENG WenLan WANG YanJun 2015Science China Earth Sciences2015,58,12:3
20Selenium-functionalized metal-organic frameworks as enzyme mimics显示文摘Weiqiang Zhou Hongfeng Li Bin Xia Wenlan Ji Shaobo Ji Weina Zhang Wei Huang Fengwei Huo Huaping Xu 2018Nano Research2018,11,10:3
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