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Estimation of Potential Habitat of Caragana acanthophylla in Xinjiang Based on Maximum Entropy Model
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作者 Jinglu zhang Yali ZHU +2 位作者 huifang zhang Jian GAO Dilixiati·Baoerhan 《Asian Agricultural Research》 2024年第4期14-18,22,共6页
[Objectives]To determine the potential habitat range of Caragana acanthophylla in Xinjiang.[Methods]The known distribution points of C.acanthophylla were used as samples,and a MaxEnt model was developed based on their... [Objectives]To determine the potential habitat range of Caragana acanthophylla in Xinjiang.[Methods]The known distribution points of C.acanthophylla were used as samples,and a MaxEnt model was developed based on their climatic variables to identify key environmental factors affecting the potential habitats of C.acanthophylla through jackknife method and construction of a response relationship between representative variables and habitat suitability;the suitability of habitats for C.acanthophylla in Xinjiang was evaluated based on the output results of the model.[Results](i)The accuracy of the model verified by AUC curve was 0.971,indicating that the potential habitats of C.acanthophylla in Xinjiang predicted by MaxEnt model were highly credible.(ii)The optimum climatic characteristics for the distribution of C.acanthophylla in Xinjiang were:isothermality 18.8%-34%,minimum temperature of coldest month-30℃to-13℃,mean temperature of coldest quarter-18℃ to-4℃,annual precipitation 80-410 mm,precipitation of driest month 0-25 mm,precipitation of driest quarter 0-82 mm,and precipitation of coldest quarter 0-75 mm.(iii)The total potential distribution area of C.acanthophylla in Xinjiang was modeled to be 1.03×10^(5) km^(2),of which 8.54×10^(3)km^(2) was high suitability area,mainly in the front mountain belt of the north slope of Tianshan Mountain in Urumqi City,Changji Hui Autonomous Prefecture,Bortala Mongol Autonomous Prefecture,and Yili Kazak Autonomous Prefecture and the front mountain belt of Barluk Mountain in Tacheng Prefecture.[Conclusions]This study is of great significance for the future scientific management,regeneration,vegetation restoration and ecological protection of C.acanthophylla. 展开更多
关键词 XINJIANG CARAGANA acanthophylla MAXENT model POTENTIAL HABITAT
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Boron separation by adsorption and flotation with Mg-Al-LDHs and SDBS from aqueous solution
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作者 Chun Bai huifang zhang +5 位作者 Qinglong Luo Xiushen Ye Haining Liu Quan Li Jun Li Zhijian Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期192-200,共9页
Layered double hydroxides(LDHs)have been shown to be effective adsorbents for boron.However,solid-liquid separation is still a problem when separating boron from industrial radioactive waste liquid.In this research,th... Layered double hydroxides(LDHs)have been shown to be effective adsorbents for boron.However,solid-liquid separation is still a problem when separating boron from industrial radioactive waste liquid.In this research,three types of Mg-Al-LDHs including Mg-Al-LDH(NO_(3)^(-)),Mg-Al-LDH(Cl^(-))and Mg-Al-LDH(SO_(4)^(2-))were applied to adsorb boron,and moreover sodium dodecylbenzenesulfonate(SDBS)was used to float the LDH particles from aqueous solution after boron adsorption.The results showed that 60 min was sufficient for the equilibrium adsorption of the three LDHs.The boron adsorption capacity of three LDHs was determined as follows:Mg-Al-LDH(NO_(3)^(-))>Mg-Al-LDH(Cl^(-))>Mg-Al-LDH(SO_(4)^(2-)),and was 2.0,0.98 and 0.2 mmol·g^(-1),each ranging from 0 to 80 mmol·L^(-1)with the initial boron concentration.The efficiency of boron removal by Mg-Al-LDH(NO_(3)^(-))and SDBS can reach up to 89.7%.Furthermore,the boron flotation mechanism of SDBS and LDHs has been studied,since SDBS as a flotation agent can react with LDHs and penetrate into the interlayer of LDHs in addition to electrostatic attraction.Therefore,LDHs in solution can be floated onto the foam layer to be separated from the solution,and the clarified solution was obtained.The method is simple and promising for boron removal from aqueous solution. 展开更多
关键词 BORON SEPARATION ADSORPTION FLOTATION Layered double hydroxide Sodium dodecyl benzene sulfonate
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Monitoring Carbon Dioxide from Space:Retrieval Algorithm and Flux Inversion Based on GOSAT Data and Using CarbonTracker-China 被引量:11
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作者 Dongxu YANG huifang zhang +3 位作者 Yi LIU Baozhang CHEN Zhaonan CAI Daren Lü 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第8期965-976,共12页
Monitoring atmospheric carbon dioxide(CO_2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of cli... Monitoring atmospheric carbon dioxide(CO_2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of climate projection. Here, we introduce a carbon flux inversion system for estimating carbon flux with satellite measurements under the support of "The Strategic Priority Research Program of the Chinese Academy of Sciences—Climate Change: Carbon Budget and Relevant Issues". The carbon flux inversion system is composed of two separate parts: the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing(IAPCAS), and Carbon Tracker-China(CT-China), developed at the Chinese Academy of Sciences. The Greenhouse gases Observing SATellite(GOSAT) measurements are used in the carbon flux inversion experiment. To improve the quality of the IAPCAS-GOSAT retrieval, we have developed a post-screening and bias correction method, resulting in 25%–30% of the data remaining after quality control. Based on these data, the seasonal variation of XCO_2(column-averaged CO_2dry-air mole fraction) is studied, and a strong relation with vegetation cover and population is identified. Then, the IAPCAS-GOSAT XCO_2 product is used in carbon flux estimation by CT-China. The net ecosystem CO_2 exchange is-0.34 Pg C yr^(-1)(±0.08 Pg C yr^(-1)), with a large error reduction of 84%, which is a significant improvement on the error reduction when compared with in situ-only inversion. 展开更多
关键词 retrieval algorithm satellite remote sensing CO2 carbon flux GOSAT
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Porous NiCo_2O_4 nanowires supported on carbon cloth for flexible asymmetric supercapacitor with high energy density 被引量:6
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作者 huifang zhang Dengji Xiao +5 位作者 Qian Li Yuanyuan Ma Shuxia Yuan Lijing Xie Chengmeng Chen Chunxiang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第1期195-202,共8页
Recently, binary metal oxides have been considerably researched for energy storage since it can provide higher electrical conductivity and electrochemical activity than single components. Besides, rational arrays stru... Recently, binary metal oxides have been considerably researched for energy storage since it can provide higher electrical conductivity and electrochemical activity than single components. Besides, rational arrays structure design can effectively enhance the utilization of active material. In this article, we synthesis a porous NiCo_2O_4 nanowires arrays, which were intimate contact with flexible carbon cloth(CC)by a facile hydrothermal reaction and calcination treatment. The rational array structures of NiCo_2O_4 facilitate the diffusion of electrolyte and effectively increase the utilization of active material. The asobtained NiCo_2O_4@CC electrode exhibits a high capacitance of 1183 mF cm^(-2) and an outstanding capacitance retention of 90.4% after 3000 cycles. Furthermore, a flexible asymmetric supercapacitor(ASC)using NiCo_2O_4@CC as positive electrode and activated carbon cloth(ACC) as negative electrode was fabricated, which delivers a large capacitance of 750 mF cm^(-2)(12.5 F cm^(-3)), a high energy density of 0.24 mWh cm^(-2)(3.91 mWh cm^(-3)), as well as excellent cycle stability under different bending states.These remarkable results suggest that as-assembled NiCo_2O_4@CC//ACC ASC is a promising candidate in flexible energy storage applications. 展开更多
关键词 All solid-stateNiCo2O4 nanowires Carbon cloth Activated carbon cloth Asymmetric supercapacitor
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Willingness to pay for environmental protection in China:Air pollution,perception,and government involvement
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作者 Yan zhang Chin-Hsien Yu +1 位作者 Ding Li huifang zhang 《Chinese Journal of Population,Resources and Environment》 2020年第3期229-236,共8页
The deteriorating environment has become an urgent global problem.As developing country,China is no exception.Demand for clean air is increasing in response to health and social problems.We use China's micro house... The deteriorating environment has become an urgent global problem.As developing country,China is no exception.Demand for clean air is increasing in response to health and social problems.We use China's micro household survey data to explore individual residents'willingness to pay for environmental protection(WTP).Results show that air pollution improves WTP.A 100​μg/m^(³)increase in PM_(2.5)leads to approximately 84.1%WTP on a given day,but local residents are habituated to local pollution.We further study air pollution affects individual perceptions.We discuss the belief that local governments take pollution seriously can promote WTP.In addition,respondents who own smartphones,demonstrate environmental awareness,are happier,and enjoy higher household assets and income are willing to pay more. 展开更多
关键词 Air pollution PM_(2.5) Willingness to pay PERCEPTION Government emphasis
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The Effect of Respiratory Rehabilitation Training on the Life Quality of Pneumoconiosis Patients
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作者 Lijun Chen Wang Xu +3 位作者 Xiaoyong Ma Genggeng Yu Jianfeng Wang huifang zhang 《Journal of Clinical and Nursing Research》 2020年第4期5-8,共4页
Objective:To explore the effect of respiratory rehabilitation training on the quality of life of pneumoconiosis patients.Methods:76 pneumoconiosis patients who were treated in our hospital from April 2017 to December ... Objective:To explore the effect of respiratory rehabilitation training on the quality of life of pneumoconiosis patients.Methods:76 pneumoconiosis patients who were treated in our hospital from April 2017 to December 2019 were selected as the research object,and randomly divided into 2 groups according to the order of admission by coin tossing,38 cases in each group.The control group carried out health knowledge education on the basis of conventiona1 treatment,and the observation group combined with respiratory rehabilitation training on the basis of the control group to compare the quality of life and lung function of the two groups of patients.Results:After 2 months of nursing care,scores of GQOLI-74 scale and pulmonary ventilation function indexes in the observation group were higher than those in the control group,with statistically significant differences(P<0.05).Conclusion:Respiratory rehabilitation training can improve pulmonary ventilation function of pneumoconiosis patients,improve the quality of life of patients,has good clinical application value. 展开更多
关键词 PNEUMOCONIOSIS Respiratory rehabilitation training Quality of life Lung function
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Analysis of Clinical and Imaging Characteristics of Suspected and Confirmed COVID-19 Patients
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作者 Lijun Chen Wang Xu +3 位作者 Jing Liu huifang zhang Juanxia Chen Xiaoyong Ma 《Journal of Clinical and Nursing Research》 2022年第1期10-14,共5页
Objective:To analyze the clinical characteristics and chest CT imaging characteristics of patients with confirmed COVID-19(COVID-19)and patients with suspected COVID-19.Methods:The study time span was from February 20... Objective:To analyze the clinical characteristics and chest CT imaging characteristics of patients with confirmed COVID-19(COVID-19)and patients with suspected COVID-19.Methods:The study time span was from February 2020 to May 2020.The case samples were selected from 72 patients with confirmed covid-19 and suspected covid-19 diagnosed and treated by The First People’s Hospital of Yinchuan and Yinchuan Temporary Emergency Hospital,including 38 patients with confirmed covid-19 and 34 patients with suspected covid-19.All patients underwent laboratory examination and chest CT examination,and the specific examination results were compared and analyzed.Results:There were significant differences in number of white blood cell,percentage of lymphocytes,creatine kinase and erythrocyte sedimentation rate between confirmed and suspected COVID-19 patients(P<0.05).The CT imaging characteristics of COVID-19 patients were compared with those of suspected COVID-19 patients.The lesions of COVID-19 patients were mostly characterized by mixed ground glass density and pure ground glass density.There were vascular thickening and interstitial thickness increase,and accompanied by bronchiectasis or air bronchogram.The distribution of lesions was mostly subpleural without pleural effusion.The lesion area of suspected COVID-19 patients mostly showed solid density and mixed ground glass density.The lesion was distributed along bronchovascular and pleural effusion was observed.Conclusion:There are some differences in biochemical indexes and chest CT images between confirmed and suspected covid-19 patients,which can be used for differential diagnosis. 展开更多
关键词 SUSPECTED DIAGNOSIS COVID-19 biochemical indexes Chest CT image
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Influence of moxibustion temperatures on blood lipids, endothelin-1, and nitric oxide in hyperlipidemia patients 被引量:11
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作者 Xianfeng Ye huifang zhang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第5期592-596,共5页
Abstract OBJECTIVE:To observe the influence of moxibustion temperature on blood lipids,endothelin-1(ET-1),nitric oxide(NO),and ET-1/NO in hyperlipidemia patients.METHODS:Forty-two primary hyperlipidemia patients were ... Abstract OBJECTIVE:To observe the influence of moxibustion temperature on blood lipids,endothelin-1(ET-1),nitric oxide(NO),and ET-1/NO in hyperlipidemia patients.METHODS:Forty-two primary hyperlipidemia patients were randomly divided into two groups of 21and treated with moxibustion at different temperatures.Moxibustion was performed with the moxa roll 2.5-3.0 cm from the skin in the treatment group and 4 cm in the control group,10 min per point,once every other day.Skin temperature was precisely measured with a thermometer during moxibustion.After a 12-week treatment,seven measurements of blood lipids,ET-1,and NO were recorded.RESULTS:Total cholesterol and triglyceride,were lower in the treatment group than in the control group(P<0.05).Serum ET-1 and ET-1/NO was obvi-ously lowered in the treatment group(P<0.001).Moxibustion regulated NO and ET-1/NO in the treatment group much better than in the control group.CONCLUSION:Moxibustion can regulate blood lipids and clear blood vessels.Moxibustion at45℃has a better effect than moxibustion at 38℃on regulating blood lipids and protecting vascular endothelial function,indicating that suitable temperature influences the curative effect of moxibustion. 展开更多
关键词 调节血脂 内皮素-1 高脂血症 一氧化氮 患者 血管内皮功能 皮肤温度 ET-1
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The Chinese carbon cycle data-assimilation system(Tan-Tracker) 被引量:7
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作者 Xiangjun Tian Zhenghui Xie +3 位作者 Zhaonan Cai Yi Liu Yu Fu huifang zhang 《Chinese Science Bulletin》 SCIE EI CAS 2014年第14期1541-1546,共6页
In this study,the Chinese carbon cyle dataassimilation system Tan-Tracker is developed based on the atmospheric chemical transport model(GEOS-Chem)platform.Tan-Tracker is a dual-pass data-assimilation system in which ... In this study,the Chinese carbon cyle dataassimilation system Tan-Tracker is developed based on the atmospheric chemical transport model(GEOS-Chem)platform.Tan-Tracker is a dual-pass data-assimilation system in which both CO2concentrations and CO2fluxes are simultaneously assimilated from atmospheric observations.It has several advantages,including its advanced data-assimilation method,its highly efficient computing performance,and its simultaneous assimilation of CO2concentrations and CO2fluxes.Preliminary observing system simulation experiments demonstrate its robust performance with high assimilation precision,making full use of observations.The Tan-Tracker system can only assimilate in situ observations for the moment.In the future,we hope to extend Tan-Tracker with functions for using satellite measurements,which will form the quasioperational Chinese carbon cycle data-assimilation system. 展开更多
关键词 跟踪系统 数据同化 碳循环 中国 CO2通量 大气观测 二氧化碳浓度 大气化学
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Salvianolic acid A alleviates renal injury in systemic lupus erythematosus induced by pristane in BALB/c mice 被引量:8
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作者 Yihuang Lin Yu Yan +6 位作者 huifang zhang Yucai Chen Yangyang He Shoubao Wang Lianhua Fang Yang Lv Guanhua Du 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2017年第2期159-166,共8页
The purpose of this study was to investigate the effects of salvianolic acid A(SAA) in systemic lupus erythematosus(SLE) induced by pristane in BALB/c mice.Lupus mice were established by confirming elevated levels of ... The purpose of this study was to investigate the effects of salvianolic acid A(SAA) in systemic lupus erythematosus(SLE) induced by pristane in BALB/c mice.Lupus mice were established by confirming elevated levels of autoantibodies and IL-6 after intraperitoneal injection of pristane.Mice were then treated with daily oral doses of SAA for 5 months in parallel with mice treated with prednisone and aspirin as positive controls.The levels of autoantibodies were monitored at monthly intervals and nephritic symptoms observed by hematoxylin and eosin(H&E) and periodic acid-Schiff(PAS) staining.Western blot analysis of renal tissue was also employed.SAA treatment caused a significant reduction in the levels of anti-Sm autoantibodies and reduced renal histopathological changes and pathological effects.SAA treatment also significantly inhibited the phosphorylation of IKK,IκB and NFκB in renal tissues of lupus mice.In conclusion,the results suggest that SAA alleviates renal injury in pristane-induced SLE in BALB/c mice through inhibition of phosphorylation of IKK,IκB and NFκB. 展开更多
关键词 Salvianolic acid A SLE Renal injury AUTOANTIBODIES PRISTANE BALB/c mice NFΚB
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All-optical active THz metasurfaces for ultrafast polarization switching and dynamic beam splitting 被引量:18
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作者 Longqing Cong Yogesh Kumar Srivastava +3 位作者 huifang zhang Xueqian zhang Jiaguang Han Ranjan Singh 《Light(Science & Applications)》 SCIE EI CAS CSCD 2018年第1期766-774,共9页
Miniaturized ultrafast switchable optical components with an extremely compact size and a high-speed response will be the core of next-generation all-optical devices instead of traditional integrated circuits,which ar... Miniaturized ultrafast switchable optical components with an extremely compact size and a high-speed response will be the core of next-generation all-optical devices instead of traditional integrated circuits,which are approaching the bottleneck of Moore’s Law.Metasurfaces have emerged as fascinating subwavelength flat optical components and devices for light focusing and holography applications.However,these devices exhibit a severe limitation due to their natural passive response.Here we introduce an active hybrid metasurface integrated with patterned semiconductor inclusions for all-optical active control of terahertz waves.Ultrafast modulation of polarization states and the beam splitting ratio are experimentally demonstrated on a time scale of 667 ps.This scheme of hybrid metasurfaces could also be extended to the design of various free-space all-optical active devices,such as varifocal planar lenses,switchable vector beam generators,and components for holography in ultrafast imaging,display,and high-fidelity terahertz wireless communication systems. 展开更多
关键词 POLARIZATION optical BEAM
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大气反演中国陆地生态系统碳收支:进展与挑战 被引量:9
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作者 陈报章 张慧芳 +1 位作者 汪涛 张小曳 《Science Bulletin》 SCIE EI CSCD 2021年第17期1713-1718,M0003,共7页
The atmospheric inversion is an effective method for quantifying surface CO_(2) fluxes at global and regional scales using the gradient of CO_(2) measurements and has the advantage of inferring CO_(2) sources and sink... The atmospheric inversion is an effective method for quantifying surface CO_(2) fluxes at global and regional scales using the gradient of CO_(2) measurements and has the advantage of inferring CO_(2) sources and sinks over large spatial scales.The“2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories”was adopted and accepted during the 49th Session of the Intergovernmental Panel on Climate Change(IPCC)in May 2019. 展开更多
关键词 scales 进展与挑战 SINK
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Polarization-independent all-silicon dielectric metasurfaces in the terahertz regime 被引量:5
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作者 huifang zhang XUEQIAN zhang +11 位作者 QUAN XU QIU WANG YUEHONG XU MINGGUI WEI YANFENG LI JIANQIANG GU ZHEN TIAN CHUNMEI OUYANG XIXIANG zhang CONG HU JIAGUANG HAN WEILI zhang 《Photonics Research》 SCIE EI 2018年第1期24-29,共6页
Dielectric metasurfaces have achieved great success in realizing high-efficiency wavefront control in the optical and infrared ranges. Here, we experimentally demonstrate several efficient, polarization-independent, a... Dielectric metasurfaces have achieved great success in realizing high-efficiency wavefront control in the optical and infrared ranges. Here, we experimentally demonstrate several efficient, polarization-independent, all-silicon dielectric metasurfaces in the terahertz regime. The metasurfaces are composed of cylindrical silicon pillars on a silicon substrate, which can be easily fabricated using etching technology for semiconductors. By locally tailoring the diameter of the pillars, full control over abrupt phase changes can be achieved. To show the controlling ability of the metasurfaces, an anomalous deflector, three Bessel beam generators, and three vortex beam generators are fabricated and characterized. We also show that the proposed metasurfaces can be easily combined to form composite devices with extended functionalities. The proposed controlling method has promising applications in developing low-loss, ultra-compact spatial terahertz modulation devices. 展开更多
关键词 光学 红外范围 通讯技术 半导体
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Magnetic beads-based multicolor colorimetric immunoassay for ultrasensitive detection of aflatoxin B_(1) 被引量:3
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作者 Shan He Qitong Huang +4 位作者 Ying zhang huifang zhang Huifeng Xu Xun Li Xiaoming Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第4期1462-1465,共4页
Aflatoxin B_(1)(AFB_(1))is one of the most toxic,mutagenic and carcinogenic mycotoxin,widely exists in contaminated food,grains and feedstuff products.In this study,a novel magnetic beads multicolor colorimetric immun... Aflatoxin B_(1)(AFB_(1))is one of the most toxic,mutagenic and carcinogenic mycotoxin,widely exists in contaminated food,grains and feedstuff products.In this study,a novel magnetic beads multicolor colorimetric immunoassay(MBMCIA)based on Au@Ag nanorods(Au@Ag NRs)is proposed to visual detect ultralow concentration of AFB_(1)with high-resolution by the naked-eye.To design the MBMCIA system,AFB_(1)-BSA conjugates were first coated on the surface of magnetic beads(MBs),then alkaline phosphatase(ALP)as a bridge between immunoassay a nd color reaction was used for catalytic hydrolysis of ascorbic acid-phosphate to generate reductive ascorbic acid.Finally,the yielded ascorbic acid could reduce silver ions to grow a silver coating on the surface of gold nanorods to generate Au@Ag NRs,which leads to the bule-shifted longitudinal absorption peak of Au NRs,accompanying with a series of perceptible color change.Under the optimal conditions,the proposed MBMCIA exhibited go od sensitivity and specificity for the detection of AFB_(1)with the detection limit as low as 5.7 pg/mL Meanwhile,the MBMCIA was also applied for the analysis of AFB_(1)in spiked wheat samples,the obtained recoveries range from 99.1%to 104.3%with relative standard deviation(RSD)less than 7.05%were acceptable.The proposed MBMCIA integrates separated,enriched,anti-interfe rence and signal read-out into one,which opens up a new avenue for an on-site visual food safety inspection or environmental monitoring. 展开更多
关键词 MYCOTOXIN Aflatoxin B_1 Magnetic beads IMMUNOASSAY MULTICOLOR COLORIMETRY
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2060年中国实现碳中和所面临的挑战:现状与展望 被引量:3
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作者 陈报章 陈发虎 +7 位作者 Philippe Ciais 张慧芳 吕洪刚 汪涛 Frédéric Chevallier 刘竹 袁文平 Wouter Peters 《Science Bulletin》 SCIE EI CAS CSCD 2022年第20期2030-2035,M0003,共7页
China’s high ambitions to reach peak CO_(2) emissions by 2030 and carbon neutrality by 2060 make carbon mitigation an urgent issue with widespread societal consequences.To develop an achievable roadmap and an effecti... China’s high ambitions to reach peak CO_(2) emissions by 2030 and carbon neutrality by 2060 make carbon mitigation an urgent issue with widespread societal consequences.To develop an achievable roadmap and an effective portfolio of climate policies,it is essential that a clear picture of the magnitude and uncertainty of China’s current carbon balance is available,at both national and regional levels. 展开更多
关键词 碳中和 consequences NEUTRAL
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Observations of atmospheric pollutants at Lhasa during 2014-2015:Pollution status and the influence of meteorological factors 被引量:9
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作者 Bu Duo Lulu Cui +6 位作者 Zhenzhen Wang Rui Li Liwu zhang Hongbo Fu Jianmin Chen huifang zhang A.Qiong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第1期28-42,共15页
Atmospheric pollutants including SO_2, NO_2, CO, O_3 and inhalable particulate matter(PM2.5 and PM10) were monitored continuously from March 2014 to February 2015 to investigate characteristics of air pollution at L... Atmospheric pollutants including SO_2, NO_2, CO, O_3 and inhalable particulate matter(PM2.5 and PM10) were monitored continuously from March 2014 to February 2015 to investigate characteristics of air pollution at Lhasa, Tibetan Plateau. Species exhibited similar seasonal variations except O_3, with the peaks in winter but low valleys in summer. The maximum O_3 concentration was observed in spring, followed by summer, autumn, and winter. The positive correlation between O_3 and PM10 in spring indicated similar sources of them, and was assumed to be turbulent transport. Temperature was the dominant meteorological factor for most species in spring. High temperature accelerates O_3 photochemistry, and favors air disturbance which is conductive to dust resuspension in spring. Relative humidity(RH) and atmospheric pressure were the main meteorological factors in summer. RH showed negative correlations with species, while atmospheric pressure posed opposite situation. Wind speed(WS) was the dominant meteorological factor in autumn, the negative correlations between WS and species indicated diffusion by wind. Most species showed non-significant correlations with meteorological factors in winter, indicating the dependence of pollution on source emission rather than restriction by meteorology. Pollution weather character indicated that emissions were from biomass burning and dust suspension, and meteorological factors also played an important role. Air stream injection from the stratosphere was observed during O_3 pollution period. Air parcels from Southwest Asia were observed during air pollution period in winter. An enhancement in air pollutants such as O_3 would be expected in the future, more attention should be given to countermeasures for prevention of air pollution in the future. 展开更多
关键词 Atmospheric pollutants Biomass burning Meteorological factors Lhasa
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Accuracy of pedicle screw placement in the thoracic and lumbosacral spines using O-arm-based navigation versus conventional freehand technique 被引量:2
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作者 Linkai Jing Zhenze Wang +3 位作者 Zhenxing Sun huifang zhang James Wang Guihuai Wang 《Chinese Neurosurgical Journal》 CSCD 2019年第3期137-143,共7页
The accuracy and safety of pedicle screw insertion was markedly improved with the introduction of intraoperative three-dimensional navigation system during the last decade. This study aimed to evaluate the accuracy of... The accuracy and safety of pedicle screw insertion was markedly improved with the introduction of intraoperative three-dimensional navigation system during the last decade. This study aimed to evaluate the accuracy of pedicle screw placement using O-arm-based navigation system versus conventional freehand technique. Methods: We reviewed the accuracy of 341 thoracic (n = 173) and lumbosacral (n = 168) pedicle screws placed in 60 consecutive patients using either O-arm-based navigation or freehand technique in the Department of Neurosurgery of Beijing Tsinghua Changgung Hospital between January 2015 and June 2018. Patient-specific characteristics, treatment-related characteristics, and screw-specific accuracy were analyzed. The accuracy of pedicle screw placement was measured by Gertzbein-Robbins scale and screw grades A and B were clinically acceptable. Results: One hundred ninety-one screws were inserted in the O-arm-based navigation group and 150 in the freehand group. One hundred eighty-three (95.81%) clinically acceptable screws were placed in the navigation group and 135 (90.00%) in the freehand group (p = 0.034). Twenty-three (6.74%) screw revisions were performed in the two groups (8 screws in the navigation group and 15 screws in the freehand group) and significant difference was observed in thoracic spine (p = 0.018), while no statistical significance was presented in lumbosacral spine (p >0.05). Twenty-four (12.57%) screws in the navigation group and 24 (16.00%) in the freehand group violated the cortex (p > 0.05). Medial screw deviation was the most common problem in the two groups. Conclusion: The O-arm-based navigation exhibits higher accuracy for pedicle screw insertion than the freehand insertion technique. 展开更多
关键词 ACCURACY FREEHAND NAVIGATION O-arm PEDICLE screw
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All dielectric metasurfaces for spin-dependent terahertz wavefront control 被引量:1
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作者 TONG WU huifang zhang +7 位作者 SIVALOGANATHAN KUMARAN YUEHONG XU QINGWEI WANG WLADISLAW MICHAILOW XUEQIAN zhang HARVEY E.BEERE DAVID A.RITCHIE JIAGUANG HAN 《Photonics Research》 SCIE EI CAS CSCD 2022年第7期1695-1702,共8页
Metasurfaces consisting of artificial subwavelength structure arrays have shown unprecedented ability to manipulate the phase,amplitude,and polarization of light.Separate and complete control over different spin state... Metasurfaces consisting of artificial subwavelength structure arrays have shown unprecedented ability to manipulate the phase,amplitude,and polarization of light.Separate and complete control over different spin states,namely the orthogonal circular polarizations,has proven more challenging as compared to the control over orthogonal linear polarizations.Here,we present and experimentally demonstrate several spin-dependent wavefront control metasurfaces in the terahertz regime using all-silicon dielectric structures.Such spin-dependent allsilicon metasurfaces are easy to fabricate and have potential applications in spin-involved ultracompact and miniaturized terahertz optical systems as well as terahertz communication systems. 展开更多
关键词 POLARIZATION DIELECTRIC SURFACES
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Application of intraoperative O-arm-assisted real-time navigation technique for spinal fixation 被引量:3
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作者 Zhenxing Sun Dan Yuan +13 位作者 Yaxing Sun Zhanquan zhang Guihuai Wang Yi Guo Guoqin Wang Dongkang Liu Peng Chen Linkai Jing Feng Yang Peihai zhang huifang zhang Youtu Wu Wei Shi James Wang 《Translational Neuroscience and Clinics》 2017年第3期135-146,共2页
This study explored the combined use of the O-arm and real-time navigation during spinal fixation. The clinical data for 60 patients undergoing spinal fixation, at Beijing Tsinghua Chang Gung Hospital between May 5, 2... This study explored the combined use of the O-arm and real-time navigation during spinal fixation. The clinical data for 60 patients undergoing spinal fixation, at Beijing Tsinghua Chang Gung Hospital between May 5, 2015 and May 1, 2017, were retrospectively analyzed. Pre-, intra-, and postoperative imaging findings were assessed. The patients were classified into the occipitocervical fusion(32 cases) and thoracic/lumbar/sacral spine fixation(28 cases, including 6 cases of percutaneous pedicle screw) groups. Lesion resections were performed microscopically. An O-arm, combined with real-time navigation, was used to assess spinal fixation. Efficacy was evaluated using operative times, X-ray times, screw positioning, and complications. Within the occipitocervical fusion group, 182 screws were placed in the cervical spine and 96 in the occipital bone. However, 6 screws penetrated the bone cortex and were adjacent to the vertebral arteries, based on O-arm three-dimensional imaging; therefore, the precision rate was 96.7%. Within the thoracic/lumbar/sacral spine fixation group, 148 pedicle screws were implanted, with 4 initially outside the vertebral body,yielding a precision rate of 97.3%. Ten percutaneous pedicle screws were implanted and well positioned. O-arm scans were performed 3 times/patient, with an average of 20–30 min/time. Screw implantation times were 5–7 min(cervical spine), 8–10 min(thoracic spine), and 6–8 min(lumbar spine). Intraoperative O-arm scans, combined with real-time navigation technology, allow real-time observation of screw angles and depths, improving the accuracy and safety of posterior screw fixations and reducing the radiation dose and frequency experienced by patients and surgeons. 展开更多
关键词 O-arm NAVIGATION spinal fixation APPLICATION
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BiodMHC:an online server for the prediction of MHC class Ⅱ-peptide binding affinity
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作者 Lian Wang Danling Pan +6 位作者 Xihao Hu Jinyu Xiao Yangyang Gao huifang zhang Yan zhang Juan Liu Shanfeng Zhu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第5期289-296,共8页
Effective identification of major histocompatibility complex (MHC) molecules restricted peptides is a critical step in discovering immune epitopes. Although many online servers have been built to predict class Ⅱ MH... Effective identification of major histocompatibility complex (MHC) molecules restricted peptides is a critical step in discovering immune epitopes. Although many online servers have been built to predict class Ⅱ MHC-peptide binding affinity, they have been trained on different datasets, and thus fail in providing a unified comparison of various methods. In this paper, we present our implementation of seven popular predictive methods, namely SMM-align, ARB, SVR-pairwise, Gibbs sampler. ProPred, LP-top2, and MHCPred, on a single web server named BiodMHC (http://biod.whu.edu.cn/BiodMHC/index.html, the software is available upon request). Using a standard measure of AUC (Area Under the receiver operating characteristic Curves), we compare these methods by means of not only cross validation but also prediction on independent test datasets. We find that SMM-align, ProPred, SVR-pairwise, ARB, and Gibbs sampler are the five best-performing methods. For the binding affinity prediction of class Ⅱ MHC-peptide, BiodMHC provides a convenient online platform for researchers to obtain binding information simultaneously using various methods. 展开更多
关键词 MHC MHC-peptide binding predictions web server
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