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1Re-Os isotopes and PGE geochemistry of black shales and intercalated Ni-Mo polymetallic sulfide bed from the Lower Cambrian Niutitang Formation, South China显示文摘The Lower Cambrian Niutitang Formation consists of a thick black shale sequence with a regionally distributed conformable Ni Mo polymetallic sulfide horizon and a chert bed at its basal strata on theYangtze Platform, South China. In this paper, we discuss all available data on Re Os isotopes and Platinum Group Element (PGE) distribution pattern of the Ni Mo polymetallic sulfide ore and its host rocks (black shales, cherts, and phosphorites) from Guizhou and Hunan provinces. Our results show that the black shales and the Ni Mo sulfide ore have a high initial 187 Os/ 188 Os ratio of 0.78~0.86, indicating that the Early Cambrian ocean across the Yangtze Platform had a highly radiogenic Os value. This ratio is slightly lower than but still similar to present day seawater, possibly as a result of high continental weathering at that time. The Ni Mo sulfide ore yields a Re Os isochron of 537±10 Ma (MSWD=11.9), possibly representing the depositional age of the Niutitang Formation. The chondrite normalized PGE pattern, Pt anomaly (Pt/Pt *), Pt/Pd, Ir/Pd, Au/Ir and Re/Mo ratios of the Ni Mo sulfide ore and its host rocks from South China indicate a varying source contribution of the PGE and other metals for different rocks. It is suggested that the cherts and Ni Mo sulfide ore may have a significant proportion of PGE and probably other metals deriving from submarine hydrothermal fluids with a mantle signature.JIANG Shaoyong*, YANG Jinghong, LING Hongfei, FENG Hongzhen, CHEN Yongquan and CHEN Jianhua(State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China) 2003Progress in Natural Science:Materials International2003,13,10:78
2Pb-Pb isotope dating of black shales from the Lower Cambrian Niutitang Formation, Guizhou Province, South China显示文摘The Lower Cambrian black shales of the Niutitang Formation and their lateral equivalents occur widely on the Yangtze Platform, South China. In this study, we examine two sections of the Niutitang Formation in Guizhou Province. We employ a stepwise acid leaching technique to obtain Pb isotope compositions of the black shales. At the Zhongnan section, the black shales display large Pb isotope variations, with 206 Pb/ 204 Pb of 20.5396~33.5709, and 207 Pb/ 204 Pb of 15.8407~16.5782. In contrast, Pb isotope data show a relatively limited range in 206 Pb/ 204 Pb (18.2797~18.5972) and 207 Pb/ 204 Pb (15.6813~15.7159) at the Zhijin section. Data for all acid leached black shale samples from the two sections yield a Pb Pb isochron age of 531±24 Ma. This age may represent the sedimentary age of the black shales. The initial Pb isotope composition of the black shales falls near the upper crust evolution curve in a Zartman Pb Pb evolution diagram. Hence, it is likely that the Pb in the black shales may have been derived from an upper continental crustal source.CHEN Yongquan, JIANG Shaoyong*, LING Hongfei, FENG Hongzhen, YANG Jinghong and CHEN Jianhua (State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China) 2003Progress in Natural Science:Materials International2003,13,10:19
3Slicing Recognition of Aircraft Integral Panel Generalized Pocket显示文摘自动地在数字控制(NC ) 获得一个用机器制造的区域编程,概括衣袋的一个数据模型被分析飞机积分面板特征,和一条特征识别途径建立被建议。由一块飞机积分面板的实际用机器制造片的进程的参考,首先,部分和空白在 Z 轴方向被切;因此特征侧面根据切的飞机被创造,轮廓被切的飞机的交叉与部分和它的空白形成。第二,概括衣袋的辅助特征也基于脸类型和位置被决定,到改正衣袋的侧面。最后,概括袖珍特征关系树被在特征之中匹配垂直关系构造。用机器制造使用这个方法生产的特征信息能直接被用来计算切割器路径。方法的有效性和有实行可能被 NC 编程为飞机面板验证。Yu Fangfang DU Baorui Ren Wenjie Zheng Guolei Chu Hongzhen 2008Chinese Journal of Aeronautics2008,21,6:15
4New Bradoriid Arthropods from the Early Cambrian Balang Formation of Eastern Guizhou, South China显示文摘The Early Cambrian Balang Formation is comprised of mudrock and shale, which was deposited in a shelf environment in the eastern part of Guizhou, south China. The Balang Fauna, which consists of seven phyla, occurs in the middle and upper parts of the Balang Formation. Arthropods are important constituents of the Balang Fauna and include a great number of trilobites, large bivalved arthropods, and newly-discovered well-preserved bradoriid fossils. The bradoriids present include three genera and four species : Comptaluta inflata (Cheng, 1974) emend Hou et al., 2002; Comptaluta kailiensis sp. nov., and Alutella elongeta sp. nov., Aluta sp. This faunal assemblage in the Balang Formation is distinguished from the Tsunyiella Chang, 1964, Songlinella Yin, 1978 and Kunmingella Hou, 1956 assemblage which occurs in the Niutitang and Mingxinsi formations of the Yangtze Platform in middle region of Guizhou and which is earlier than the Balang Formation in age. However, this assemblage resembles the Comptaluta pik, 1968 assemblage from the Early Cambrian Heilinpu Formation in Wuding County, Yuanan Province and from the Ordian Stage of the Cambrian of Australia. The great abundance of Comptaluta pik, 1968 and overall taxonomic diversity of the Comptaluta pik, 1968 assemblage set it distinctly apart from the Alutella Kobayashi et Kato, 1951 and Aluta Hou, 1956 assemblages of the Balang Formation. Alutella Kobayashi et Kato, 1951 and Aluta Hou, 1956 also occur in the Early Cambrian Niutitang Formation of the Yangtze Platform of Guizhou. Individual Bradoriids from the Balang Formation are characterized by large size (>3 mm). The discovery of new Bradoriid assemblages not only expands the group’s geographical range and assemblage affinities, but also indicates that Bradoriids migrated eastward from shallow-water to deeper-water environments during the Early Cambrian, indicating that they were capable of life in deeper-water, and adaptation to a new ecological setting.PENG Jin FENG Hongzhen FU Xiaoping ZHAO Yuanlong YAO Lu 2010Acta Geologica Sinica(English Edition)2010,84,1:13
5FLOW DIRECTION OF PIEZOELECTRIC PUMP WITH NOZZLE/DIFFUSER-ELEMENTS显示文摘The piezoelectric pump with nozzle/diffuser-elements, which oscillating form differing from regular volumetric reciprocating or rotating pumps because there are nozzle/diffuser-elements substituted for regular valves, is a new type pump whose actuator is a piezoelectric ceramal part with verse piezoelectric effect.In recent year, piezoelectric pump is paid increasing attention to because it is an ideal candidate in application in such area as medical health, mechanical tools and micro-mechanism.The fundamental research on it, however, is still not made through.Focuses on the phenomenon of different directions of flow among Germany pump, Chinese pump and Swiss pump, which are all fitted with nozzle/diffuser-elements, and analyzes the cone angle of nozzle/diffuser-elements based on the flow equation of valve-less piezoelectric pump with nozzle/diffuser-elements.As a result, the concepts of diffuser loss coefficient and loss coefficient are introduced to explain these phenomena, from which a discussion is given on the optimization of the cone angle of nozzle/diffuser-element aiming at the maximum of pump flow.ZhangJianhui XiaQixiao HongZhen OnukiAkiyoshi 2004Chinese Journal of Mechanical Engineering2004,17,1:13
6Predicting As,Cd and Pb uptake by rice and vegetables using field data from China显示文摘Plant uptake factor(PUF),single-variable regression of natural log-transformed concentrations in rice grain/vegetables versus natural log-transformed concentrations in soil and multiple-variable regression with soil concentrations and pH,was derived,validated and compared based on the paired crop and soil data collected from studies regarding As,Cd and Pb contaminated croplands in China.Results showed that the median value of PUF did not present deterministic prediction.But after natural logarithm transformation,the PUF followed Gaussian distribution which could be useful in risk assessment.The single-variable regression models were significant for As,Cd and Pb uptake both by rice and vegetables;however,the standard errors of all the regressions were comparatively large.Soil pH as a variable was generally significant but it only contributed positively to model fit for Cd uptake.After model comparison and selection,the upper 95% prediction limits of the multiple regression model for Cd uptake by rice was recommended to calculate screening value of Cd for paddy soil based on the limit for Cd concentration in rice grain.Hongzhen Zhang Yongming Luo Jing Song Haibo Zhang Jiaqi Xia Qiguo Zhao 2011Journal of Environmental Sciences2011,23,1:12
7A Scheme of the Hierarchy for Sequence Stratigraphy显示文摘Depositional sequences may be distinguished into six ranks of units as giga-, mega-, meso-, ortho-, sub- and micro-sequence, and are interpreted to be formed during the eustatic cycles with time-intervals of 500-6000 Ma, 60-120 Ma, 30-40 Ma, 2-5 Ma, 0.1-0.4 Ma and 0.02-0.04 Ma respectively. All of them are thought to be essentially related to cosmological cycles, except the megasequence which may be caused by the long-term geothermal cycles on cratons. We deem that the depositional sequences, though often influenced variably by local tectonics and other factors, are primarily global and periodic in nature. We also hold that as one of the planets within the Galaxy, the earth must have been affected in various ways by other asteroids, and that the depositional sequences are merely the responses of the hydrosphere to the cosmological cycles in sedimentation.Wang Hongzhen Shi Xiaoying (Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083) 1996Journal of Earth Science1996,15,1:11
8Face Image Recognition Based on Convolutional Neural Network显示文摘With the continuous progress of The Times and the development of technology,the rise of network social media has also brought the“explosive”growth of image data.As one of the main ways of People’s Daily communication,image is widely used as a carrier of communication because of its rich content,intuitive and other advantages.Image recognition based on convolution neural network is the first application in the field of image recognition.A series of algorithm operations such as image eigenvalue extraction,recognition and convolution are used to identify and analyze different images.The rapid development of artificial intelligence makes machine learning more and more important in its research field.Use algorithms to learn each piece of data and predict the outcome.This has become an important key to open the door of artificial intelligence.In machine vision,image recognition is the foundation,but how to associate the low-level information in the image with the high-level image semantics becomes the key problem of image recognition.Predecessors have provided many model algorithms,which have laid a solid foundation for the development of artificial intelligence and image recognition.The multi-level information fusion model based on the VGG16 model is an improvement on the fully connected neural network.Different from full connection network,convolutional neural network does not use full connection method in each layer of neurons of neural network,but USES some nodes for connection.Although this method reduces the computation time,due to the fact that the convolutional neural network model will lose some useful feature information in the process of propagation and calculation,this paper improves the model to be a multi-level information fusion of the convolution calculation method,and further recovers the discarded feature information,so as to improve the recognition rate of the image.VGG divides the network into five groups(mimicking the five layers of AlexNet),yet it USES 3*3 filters and combines them as a convolution sequence.Network deeper DCNN,channel number is bigger.The recognition rate of the model was verified by 0RL Face Database,BioID Face Database and CASIA Face Image Database.Guangxin Lou Hongzhen Shi 2020China Communications2020,17,2:10
9A novel miR167a-OsARF6-OsAUX3 module regulates grain length and weight in rice显示文摘Grain size is one of the most important factors that control rice yield,as it is associated with grain weight(GW).To date,dozens of rice genes that regulate grain size have been isolated;however,the regulatory mechanism underlying GW control is not fully understood.Here,the quantitative trait locus qGL5 for grain length(GL)and GW was identified in recombinant inbred lines of 9311 and Nipponbare(NPB)and fine mapped to a candidate gene,OsAUX3.Sequence variations between 9311 and NPB in the OsAUX3 promoter and loss of function of OsAUX3 led to higher GL and GW.RNA sequencing,gene expression quantification,dual-luciferase reporter assays,chromatin immunoprecipitation-quantitative PCR,and yeast one-hybrid assays demonstrated that OsARF6 is an upstream transcription factor regulating the expression of OsAUX3.OsARF6 binds directly to the auxin response elements of the OsAUX3 promoter,covering a single-nucleotide polymorphism site between 9311 and NPB/Dongjin/Hwayoung,and thereby controls GL by altering longitudinal expansion and auxin distribution/content in glume cells.Furthermore,we showed that miR167a positively regulate GL and GW by directing OsARF6 mRNA silencing.Taken together,our study reveals that a novel miR167a-OsARF6-OsAUX3 module regulates GL and GW in rice,providing a potential target for the improvement of rice yield.Jiyue Qiao Hongzhen Jiang Yuqing Lin Lianguang Shang Mei Wang Dongming Li Xiangdong Fu Markus Geisler Yanhua Qi Zhenyu Gao Qian Qian 2021Molecular Plant2021,14,10:8
10Efficient Certificateless Designated Verifier Signatures and Proxy Signatures显示文摘DU Hongzhen WEN Qiaoyan 2009Chinese Journal of Electronics2009,18,1:8
11Development of nutritious rice with high zinc/selenium and low cadmium in grains through QTL pyramiding显示文摘Enriching zinc(Zn) and selenium(Se) levels,while reducing cadmium(Cd) concentration in rice grains is of great benefit for human diet and health.Large natural variations in grain Zn, Se, and Cd concentrations in different rice accessions enable Zn/Sebiofortification and Cd-minimization through molecular breeding. Here, we report the development of new elite varieties by pyramiding major quantitative trait loci(QTLs) that significantly contribute to high Zn/Se and low Cd accumulation in grains. A chromosome segment substitution line CSSLGCC7 with the PA64s-derived GCC7 allele in the 93-11 background, exhibited steadily higher Mn and lower Cd concentrations in grains than those of 93-11. This elite chromosome segment substitution line(CSSL) was used as the core breeding material to cross with CSSLs harboring other major QTLs for essential mineral elements, especially CSSLGZC6 for grain Zn concentration and CSSLGSC5 for grain Se concentration. The CSSLGCC7+GZC6 and CSSLGCC7+GSC5 exhibited lower Cd concentration with higher Zn and Se concentrations in grains, respectively. Our study thus provides elite materials for rice breeding targeting high Zn/Se and low Cd concentrations in grains.Chaolei Liu Shilin Ding Anpeng Zhang Kai Hong Hongzhen Jiang Shenglong Yang Banpu Ruan Bin Zhang Guojun Dong Longbiao Guo Dali Zeng Qian Qian Zhenyu Gao 2020Journal of Integrative Plant Biology2020,62,3:7
12Expression and clinical significance of HIF-1α,VEGF and Survivin in esophageal squamous cell carcinoma显示文摘Objective:To evaluate the expression and correlation of hypoxia inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF)and Survivin proteins in biopsy specimens of esophageal squamous cell carcinoma(ESCC), and then determine whether the levels of expression of these proteins could predict the clinical effectiveness of radiotherapy in individual cancers.Methods:The expressions of HIF-1α,VEGF and Survivin were shown by S-P immunohistochemical stainingmethodinbiopsyspecimensofESCC,whichwereobtainedendoscopicallyfrom50patientsbeforeradiotherapy,and 10 cases of normal esophageal tissue.Results:The positive expression rates of HIF-1α,VEGF and Survivin were 68%,74% and72%inESCCrespectively.However,thethreetumormarkershadnegativeexpressionsinnormalesophagealtissue.The positive rate of HIF-1αwas positively correlated with VEGF and Survivin proteins.The positive rates of HIF-1αand Survivin were closely related to the clinical stage,radiotherapy effectiveness and survival,otherwise,the expression of HIF-1αwas closely related to distant metastasis;both of them were no correlation with the differentiation degree of tumor.The effective rates of radiotherapy and mean survival periods of those cases with positive and negative expressions of HIF-1αwere 8.8%, 10 months and 81.25%,25 months,respectively.The one,two,and three years survival rates of patients with positive and negative expressions of HIF-1αwere 38.2%,5.9%,2.9%,and 81.3%,54.2%,15.8%,respectively(P=0.001).Patients with HIF-1αpositive expression obviously survived less than those with negative expression and the difference was significant. The expression of VEGF was only related to the distant metastasis.Conclusion:Over expressions of HIF-1α,VEGF and Survivin were found in ESCC.The positive rate of HIF-1αwas positively correlated with VEGF and Survivin proteins.The expression of HIF-1αmay serve as an important parameter in evaluating response for radiotherapy and prognosis of ESCC. It may play an important role by up-regulating the transcription of VEGF and Survivin genes.Hongzhen Zhang Yazhen Wang Ning Xu Shuchai Zhu Bin Liu 2007The Chinese-German Journal of Clinical Oncology2007,6,4:7
13Superplastic behaviour and microstructure evolution of a fine-grained TA15 titanium alloy显示文摘The fine-grained microstructure of TA15 titanium alloy was prepared through two-step forging technology combined with high and low temperatures, and a transnormal superplastic elongation of more than 2000% was obtained. The superplastic behaviour and microstructure evolution were systematically researched at different temperatures and strain rates through superplastic tensile test. The results indicate that the fine-grained TA15 alloy exhibits superplasticity at temperatures of 760-980°C and initial strain rates from 1.1 × 10-2 to 5.5 × 10-5 s-1. The optimal superplastic conditions are 940°C and 3.3 × 10-4 s-1, in which the average elongation is 2526% and the maximum elongation is 2743%. During superplastic deformation, dynamic recovery and recrystallization occur obviously, and the corporate effect of strain hardening and recrystallization softening decides the superplastic ability directly.ZHAO Zhanglong GUO Hongzhen CHEN Li YAO Zekun 2009Rare Metals2009,28,5:6
14Immunotherapy of Epstein-Barr Virus Associated Malignancies Using Mycobacterial HSP70 and LMP2A356-364 Epitope Fusion Protein显示文摘Epstein-Barr virus infection is strongly associated with a number of malignancies.The EBV latent membrane protein 2A has been implicated as one of the most attractive candidates for immunotherapy of related malignancies.In previous studies,the T cell epitopes of LMP2A have been identified systematically.However,the epitope-based vaccine generally meets inefficient immunogenicity when used in vivo directly,which could be overcome by combination with appropriate adjuvants.Heat shock protein is a natural chaperon,which is able to activate the classical major histocompatibility complex class I antigen-processing pathway(cross-presentation).In this study,a minigene encoding LMP2A356-364(FLYALALLL)was genetically fused to the carboxy-terminal of mycobacterial heat shock protein 70.The epitope fusion protein was expressed and purified,and the cross-presentation of LMP2A_(356-364) by monocyte-derived dendritic cells pulsed with the epitope fusion protein was evaluated.Results showed that the epitope fusion protein-pulsed mDCs were much more efficient than the single peptide-pulsed mDCs on CTL activation.Immunization of HLA-A2.1 transgenic mice with MtHsp70-LMP2A_(356-364) generated peptide specific CTL more effectively than a single peptide plus incomplete Freund's adjuvant(IFA).Growth of LMP2A expressing B16 melanoma tumor cells was suppressed in the vaccinated groups.Our results suggested that MtHsp70-LMP2A_(356-364) fusion protein was more effective than the CD8^(+)T cell epitope alone on anti-tumor immunity.As a result,the MtHsp70-LMP2A_(356-364) fusion protein is considered to be a promising candidate vaccine for EBV related malignancies.Genyan Liu Kun Yao Bing Wang Yun Chen Feng Zhou Yidi Guo Jian Xu Hongzhen Shi 2009Cellular & Molecular Immunology2009,6,6:6
15DISCOVERY AND ANALYSIS ON CAVI TATION IN PIEZOELECTRIC PUMPS显示文摘The contributing factors for the cavitation in piezoelectric pumps are analyzed,theoretically, and the device fitting for observing and recording is set up. With it the experiments are carried out to observe the emergence and the flowing of the cavitations in the piezoelectric pumps. According to the statistic and the analysis to the data of the experiments, the peculiar features are discovered. These features are composed of balls-amassing, center-more, and flow-out.ZhangJianhui XiaQixiao LaiDehua OnukiAkiyoshi HongZhen 2004Chinese Journal of Mechanical Engineering2004,17,4:6
16Seasonal phenotypic flexibility in body mass,basal thermogenesis,and tissue oxidative capacity in the male Silky Starling(Sturnus sericeus)显示文摘Background: Acclimatization to winter conditions is an essential prerequisite for the survival of small birds in the northern temperate zone.Changes in photoperiod,ambient temperature and food availability trigger seasonal physiological and behavioral acclimatization in many passerines.Seasonal trends in metabolic parameters are well known in avian populations from temperate environments;however,the physiological and biochemical mechanisms underlying these trends are incompletely understood.In this study,we used an integrative approach to measure variation in the thermogenic properties of the male Silky Starling(Sturnus sericeus) at different levels or organization,from the whole organism to the biochemical.We measured body mass(Mb),basal metabolic rate(BMR),energy budget,the mass of selected internal organs,state 4 respiration and cytochrome c oxidase(COX) activity in the heart,liver and muscle.Methods: Oxygen consumption was measured using an open-circuit respirometry system.The energy intake of the birds were then determined using an oxygen bomb calorimeter.Mitochondrial state 4 respiration and COX activity in heart,liver and pectoral muscle were measured with a Clark electrode.Results: The results suggest that acclimatization to winter conditions caused significant change in each of the measured variables,specifically,increases in Mb,organ mass,BMR,energy intake and cellular enzyme activity.Furthermore,BMR was positively correlated with body mass,energy intake,the mass of selected internal organs,state 4 respiration in the heart,liver and muscle,and COX activity in the heart and muscle.Conclusions: These results suggest that the male Silky Starling's enhanced basal thermogenesis under winter conditions is achieved by making a suite of adjustments from the whole organism to the biochemical level,and provide further evidence to support the notion that small birds have high phenotypic plasticity with respect to seasonal changes.Min Li Yingqiao Sun Hongzhen Mao Jinhua Xu Weihong Zheng Jinsong Liu 2017Avian Research2017,8,4:6
17Effect of Multiple Forging on Microstructure and Mechanical Properties of Powder Metallurgy FGH4096 Superalloy显示文摘FGH4096 is an important damage-tolerance-type powder metallurgy (PM) superalloy, which is also the optimized turbine material for high performance aero-engine. To turbine disc, bore and rim are used in high temperature-low stress condition and low temperature-high stress condition, and dual-microstructure is introduced. Coarse-grained microstructure is suit for rim region and fine-grained is no doubt most suitable for bore region. But fine-grained ingot can not make by PM technique, so that gradient heat treatment can not be developed to coarsen the grain of rim region. Under the confine of PM technique, several treatment processing should be taken place to refine the coarse grains of PM alloy. Multiple forging with large accumulate deformation was carried out on PM FGH4096 superalloy, and fine grains of 3.5 μm were obtained by this treatment processing. Mechanical properties testing were take carried out on both fine-grained and other statuses alloys. Microstructure evolution was observed by optical microscopy, scanning electron microscopy and transmission electron microscopy. As a result of repeated dynamic recrystallization, coarse grains could be completely refined into fine grains. And the increase of strength was mainly attributed to refinement effect and improvement of defects such as previous particle boundaries. Successful development of fine-grained treatment processing will promote the research of dual-microstructure turbine disc.NING Yongquan YAO Zekun GUO Hongzhen TAO Yu ZHANG Yiwen 2009Chinese Journal of Mechanical Engineering2009,22,6:5
18Spatial heterogeneity and source apportionment of soil metal(loid)s in an abandoned lead/zinc smelter显示文摘Metal smelting have brought severe metal(loid)s contamination to the soil.Spatial distribution and pollution source analysis for soil metal(loid)s in an abandoned lead/zinc smelter were studied.The results showed that soil was contaminated heavily withmetal(loid)s.The mean of lead(Pb),arsenic(As),cadmium(Cd),mercury(Hg)and antimony(Sb)content in topsoil is 9.7,8.2,5.0,2.3,and 1.2 times higher than the risk screening value for soil contamination of development land of China(GB36600-2018),respectively.Cd ismainly enriched in the 0–6mdepth of site soil while As and Pbmainly deposited in the 0–4mlayer.The spatial distribution of soil metal(loid)s is significantly correlated with the pollution source in the different functional areas of smelter.As,Hg,Sb,Pb and copper(Cu)were mainly distributed in pyrometallurgical area,while Cd,thallium(Tl)and zinc(Zn)was mainly existed in both hydrometallurgical area and raw material storage area.Soil metal(loid)s pollution sources in the abandoned smelter are mainly contributed to the anthropogenic sources,accounting for 84.5%.Specifically,Pb,Tl,As,Hg,Sb and Cumainly from atmospheric deposition(55.9%),Cd and Zn mainly from surface runoff(28.6%),While nickel(Ni)mainly comes from parent material(15.5%).The results clarified the spatial distribution and their sources in different functional areas of the smelter,providing a new thought for the risk prevention and control of metal(loid)s in polluted site soil.Yunxia Zhang Tianshuang Li Zhaohui Guo Huimin Xie Zhihao Hu Hongzhen Ran Changzhou Li Zhichao Jiang 2023Journal of Environmental Sciences2023,,5:5
19Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010显示文摘Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China.LIU Qinping YANG Yongchun TIAN Hongzhen ZHANG Bo GU Lei 2014Chinese Geographical Science2014,24,2:5
20Electrochemical Kinetic Modulators in Lithium–Sulfur Batteries:From Defect-Rich Catalysts to Single Atomic Catalysts显示文摘Lithium–sulfur batteries exhibit unparalleled merits in theoretical energy density(2600 W h kg^(-1))among next-generation storage systems.However,the sluggish electrochemical kinetics of sulfur reduction reactions,sulfide oxidation reactions in the sulfur cathode,and the lithium dendrite growth resulted from uncontrollable lithium behaviors in lithium anode have inhibited high-rate conversions and uniform deposition to achieve high performances.Thanks to the“adsorption-catalysis”synergetic effects,the reaction kinetics of sulfur reduction reactions/sulfide oxidation reactions composed of the delithiation of Li_(2)S and the interconversions of sulfur species are propelled by lowering the delithiation/diffusion energy barriers,inhibiting polysulfide shuttling.Meanwhile,the anodic plating kinetic behaviors modulated by the catalysts tend to uniformize without dendrite growth.In this review,the various active catalysts in modulating lithium behaviors are summarized,especially for the defect-rich catalysts and single atomic catalysts.The working mechanisms of these highly active catalysts revealed from theoretical simulation to in situ/operando characterizations are also highlighted.Furthermore,the opportunities of future higher performance enhancement to realize practical applications of lithium–sulfur batteries are prospected,shedding light on the future practical development.Jing Zhang Caiyin You Hongzhen Lin Jian Wang 2022Energy & Environmental Materials2022,5,3:5
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