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Frontiers of Structural and Civil Engineering 2012年第3期6卷 257-266页

作者： bing xia Yuching WU Zhanfei HUANG Shanghai Tong Hao Civil Engineering Consultant Co.Ltd. Shanghai 200092China Department of Building Engineering College of Civil Engineering Tongji UniversityShanghai 200092China Land Transport Authority of Singapore Singapore 219428Singapore

In this paper,the co-rotational total Lagrangian forms of finite element formulations are derived to perform elasto-plastic analysis for plane steel frames that either experience increasing external loading at ambient temperature or constant external loading at elevated *** nonlinearities and thermal-expansion effects are considered.A series of programs were developed based on these *** verify the accuracy and efficiency of the nonlinear finite element programs,numerical benchmark tests were performed,and the results from these tests are in a good agreement with the *** effects of the nonlinear terms of the stiffness matrices on the computational results were investigated in *** was also demonstrated that the influence of geometric nonlinearities on the incremental steps of the finite element analysis for plane steel frames in the presence of fire is limited.

关键词： co-rotational total Lagrangian geometrical nonlinearity fire elasto-plastic

Calibratio performance evaluation of the spaceborne hyperspectral CHRIS imager

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Science China(Technological Sciences) 2006年第z2期49卷 88-96页

作者： ZHANG xia ZHANG bing HU Fangchao TONG Qingxi State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100101 China

The CHRIS (Compact High Resolution Imaging Spectrometer) is a new imaging spectrometer, carried on board a new space platform called PROBA (Project for On Board Autonomy). The satellite was successfully launched in October 2001 by the European Space Agency (ESA). CHRIS operates over the visible/near infrared band (400-1050 nm). It has five work modes and can reach a maximum of 62 spectral bands. In this research, atmospheric correction based on hyperspectral images was performed on CHRIS images by using the popular radiance transfer code ACORN (Atmospheric Correction Now) and empirical algorithms. ACORN was also used to evaluate the calibration performance of CHRIS by the retrieved spectra of typical vegetation and soil. As a result,the maize reflectance spectrum corrected by ACORN could characterize vegetation reflectance in the range of 498-750 nm, but gave a fairly large deviation beyond 750 nm,showing the deficiency of spectral calibration beyond 750 nm. The ACORN-derived soil reflectance decreased beyond 800 nm, which was quite inconsistent with field-spectrummeasurement and showed that the calibration accuracy couldn't meet the requirements of ACORN for spectral and radiometric calibration within a certain spectral range. In addition,the stripes on the retrieved water-vapor content map indicated that the radiance-calibration performance of CHRIS is not perfect. As the first spaceborne hyperspectral imager of ESA, the calibration performance of CHRIS needs to be improved.

关键词： CHRIS, hyperspectral, calibration performance, image-based atmospheric correction.

Asymmetric synthesis of difluorinatedα-quaternary amino acids(DFAAs)via Cu-catalyzed difluorobenzylation of aldimine esters

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Chinese Chemical Letters 2024年第12期35卷 416-421页

作者： xiang Huang Dongzhen Xu Yang Liu xia Huang Yangfan Wu Dongmei Fang bing xia Wei Jiao Jian Liao Min Wang Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China Natural Product Research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Increasing interests of difluorinated amino acids(DFAAs)have been raised in recent years due to their widespread bio-organic and medical ***,to date,only few investigations focused on their asymmetric *** difluoromethyl reagent to tailor a novel pathway and developing efficient catalytic system are highly desirable for constructing structurally diverse chiral ***,a copper-catalyzed asymmetric difluorobenzylation of aldimine esters is *** usingα,α-difluorinated benzyltriflones as difluoromethyl reagents,this protocol allows the asymmetric synthesis ofα-quaternary DFAAs with wide scope,good yields and excellent enantioselectivities(90%-98%ee).Control experiments and DESI-MS analysis demonstrate the reaction probably proceeds via a key difluorocarbocation ***,polyfluoroarenes are found efficient candidates to polyfluoroaryl amino acids via C-F ***-scale experiment,late-stage functionalization,synthesis of difluorinated dipeptides and bioactive molecular analogues revealed the utility of the protocol,thereby largely enriching the structural diversity of FAAs and providing more potential opportunities in drug discovery.

关键词： Cu-catalyzed Asymmetric difluorobenzylation Difluorobenzylatedα-quaternary amino acids Polyfluoroaryl amino acids Difluorocarbocation

Relationship Between Grain Yield and Yield Components in Super Hybrid Rice

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Agricultural Sciences in China 2011年第10期10卷 1537-1544页

作者： HUANG Min ZOU Ying-bin JIANG Peng xia bing Md Ibrahim AO He-jun College of Agronomy Hunan Agricultural University Changsha 410128 P.R.China

Chinese super hybrid rice breeding project has developed many new varieties with great yield potential. It is controversial which yield component should be emphasized in super hybrid rice production. The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions, and evaluate relationships between grain yield and yield components of super hybrid rice in farmer’s paddy fields. Field experiments were done in Changsha, Guidong, and Nanxian, Hunan Province, China, from 2007 to 2009. Eight super hybrid varieties, one common hybrid variety, and one super inbred variety were grown in each location and year. Rice production investigation was undertaken in high-yielding （Guidong）, moderate-yielding （Nanxian）, and low-yielding （Ningxiang） regions of Hunan Province, China, in 2009. Grain yield and yield components were measured in both the field experiments and rice production investigation. Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years. Yield potential has been increased by 11.4% in super hybrid rice varieties compared with common and super inbred varieties. The higher yield of super hybrid varieties was attributed to improvement in panicle size. Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1, and was positively related to grain yield in farmer’s field at all of the high-, moderate-, and low-yielding regions. Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.

关键词： super hybrid rice yield panicle number panicle size

Highly efficient uptake of ultrafine mesoporous silica nanoparticles with excellent biocompatibility by Liriodendron hybrid suspension cells

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Science China(Life Sciences) 2013年第1期56卷 82-89页

作者： xia bing DONG Chen ZHANG WenYi LU Ye CHEN JinHui SHI JiSen Key Laboratory of Forest Genetics & Biotechnology (Ministry of Education of China) Nanjing Forestry University Advanced Analysis and Testing Center Nanjing Forestry University

The characteristics of the interactions co-cultures of ultrafine mesoporous silica nanoparticles （MSNs） and the Liriodendron hybrid suspension cells were systematically investigated using laser scanning confocal microscope （LSCM） and scanning elec- tron microscopy （SEM）. Using fluorescein isothiocyanate （FITC） labeling, the LSCM observations demonstrated that MSNs （size, 5-15 nm） with attached FITC molecules efficiently penetrated walled plant cells through endocytic pathways, but free FITC could not enter the intact plant cells, The SEM measurements indicated that MSNs readily aggregated on the surface of intact plant cells, and also directly confirmed that MSNs could enter intact plant cells; this was achieved by determining the amount of silicon present. After 24 h of incubation with 1.0 mg mL-t of MSNs, the viability of the plant cells was analyzed using fluorescein diacetate staining; the results showed that these cells retained high viability, and no cell death was observed. Interestingly, after the incubation with MSNs, the Liriodendron hybrid suspension cells retained the capability for plant regen- eration via somatic embryogenesis. Our results indicate that ultrafine MSNs hold considerable potential as nano-carriers of ex- tracellular molecules, and can be used to investigate in vitro gene-delivery in plant cells.

关键词： mesoporous silica nanoparticles endocytosis cytotoxicity somatic embryogenesis

Effects of rhamnolipids on bacterial communities in a dioxin-contaminated soil and the gut of earthworms added to the soil

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Pedosphere 2023年第6期33卷 927-937页

作者： bing xia Dan HUANG Mao YE Hao QIU Hongfeng CHEN Keqiang ZHAO Rongliang QIU Rongrong YING Nanjing Institute of Environmental Sciences of the Ministry of Environmental Protection(NIES) Nanjing 210042China Research Academy of Environmental Sciences of Anhui Province Hefei 230071China College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Shanghai Jiao Tong University School of Environmental Science and EngineeringShanghai 200240China Guangdong Laboratory for Lingnan Modern Agriculture College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China

The biosurfactants rhamnolipids and the “soil ecosystem engineers” earthworms are often used to remediate contaminated soils. However, the effects of rhamnolipids on earthworm intestinal flora and microbial community in soil containing earthworms are not clearly understood. In our study, a 21-d microcosm experiment was carried out to reveal the effects of rhamnolipids on microbial abundance, composition, and metabolism, as well as contaminant degradation capacity. Both rhamnolipids and earthworms had positive effects on soil bacteria. Rhamnolipid-amended soil(RT) showed higher bacterial abundance and metabolic activity than earthworm-amended soil(ET), while the improvement in bacterial composition and contaminant degradation capacity by rhamnolipids was lower than that by earthworms. Notably, these effects were further amplified by the combined treatment of rhamnolipids and earthworms(RET). Specifically, the bacterial abundance(log-transferred) increased from 9.5 copies g-1in the control with no addition to 10.3, 10.6, and 11.1 copies g-1in ET, RT, and RET, respectively. Compared to ET, the relative abundance of the dominant phylum, Proteobacteria, increased from 41.66% to 51.67% in RET,and more pollutant-degrading bacteria were also enriched in RET. Therefore, the increases in bacterial abundance and contaminant-degrading bacteria led to the following ranking of soil dioxin removal rate: RET(77.28%) > ET(59.83%) > RT(24.65%) > control(4.71%). Moreover, the addition of rhamnolipids enhanced the abundance of bacterial functional genes involved in metabolism and environmental information processing. In addition, the composition and diversity of bacteria in the gut of earthworms were conspicuously affected by rhamnolipids, and the relative abundance of Microbacterium and Shewanella increased significantly(P < 0.05). Therefore, this study revealed that rhamnolipids remarkably influenced the abundance, composition, and metabolism of the microbial community in earthworm g

关键词： bioremediation biosurfactant contaminant-degrading bacteria intestinal bacteria metabolic pathway metabolism microcosm experiment soil pollution

Charge transfer on porous silicon membranes studied by current-sensing atomic force microscopy

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Chinese Chemical Letters 2008年第2期19卷 199-202页

作者： bing xia Qiang Miao Jie Chao Shou Jun xiao Hai Tao Wang Zhong Dang xiao State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China State Key Laboratory of Molecular and Biomolecular Electronics Southeast University Nanjing 210096 China

A visible rectification effect on the current-voltage curves of metal/porous silicon/p-silicon has been observed by current-sensing atomic force microscopy. The current-voltage curves of porous silicon membranes with different porosities, prepared through variation of etching current density for a constant time, indicate that a higher porosity results in a higher resistance and thus a lower rectification, until the current reaches a threshold at a porosity 〉55%. We propose that the conductance mode in the porous silicon membrane with porosities 〉55% is mainly a hopping mechanism between nano-crystallites and an inverse static electric field between the porous silicon and p-Si interface blocks the electron injection from porous silicon to p-Si, but with porosities ≤55%, electron flows through a direct continuous channel between nano-crystallites.

关键词： Porous silicon Current sensing AFM Electron transfer Porosity

A Quantum Chemistry Study of Inhibition Properties of Imidazole and Its Derivatives on Iron Surface Corrosion

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Chemical Research in Chinese Universities 2001年第3期17卷 305-310页

作者： YAN xiao-ci xia Wen-bing LIU Jie OU YANG-li LUO Ming-dao YANG Feng MIN Xin-min Department of Chemistry Wuhan UniversityWuhan 430072P.R.China National Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070P.R.China

The geometries of imidazole and its derivatives were respectively optimized by using ab initio method, and the molecular orbital energy levels and the charge densities were obtained for their optimum geometries. The frontier orbital energy levels, and the net charges of N (1) atom and the imidazole ring of those molecules were obtained with ab initio and SCC-DV-Xα methods. It was found that the inhibition properties of those compounds change with the highest occupied molecular orbital energy levels, and the net charges of N (1) atom. We took four iron atoms on the crystal plane (100) of α-iron as the surface which was used to study the adsorption towards the inhibitors. The adsorption models of the inhibitor to be adsorbed on the Fe-cluster surface were optimized with SCC-DV-Xα method. It turns out that the most favorable model is that the inhibitor molecule is adsorbed on the Fe-cluster surface in an inclined state. The calculation shows that the stabilization energies of the systems are well correlated with the inhibition efficiencies.

关键词： Imidazole ab initio SCC-DV-Xα algorithm Fe-cluster surface Inhibition efficiency

中小学生高度近视发生风险预测模型：基于巢式病例对照研究

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中国全科医学 2025年第9期28卷 1115-1121页

作者：陈胜蓝郑永韬胡旺成倪作为夏冰叶春梅杜持新陈晓丹浙江省杭州市萧山区疾病预防控制中心监测科浙江大学医学院附属第一医院护理部浙江萧山医院质管科浙江省杭州市临平区疾病预防控制中心免疫规划管理科

背景中小学生由于学习压力、电子产品普及以及不良用眼习惯，视力健康问题日益严重，成为近视的高发群体，高度近视作为近视的严重阶段，已成为全球范围内的公共卫生问题。尽管现有诸多研究对近视的危险因素进行了探讨，但鲜有研究针对... 详细信息

背景中小学生由于学习压力、电子产品普及以及不良用眼习惯，视力健康问题日益严重，成为近视的高发群体，高度近视作为近视的严重阶段，已成为全球范围内的公共卫生问题。尽管现有诸多研究对近视的危险因素进行了探讨，但鲜有研究针对性阐明风险因素与高度近视发生的复杂非线性关系，本研究结合巢式病例对照研究和限制性立方样条，开发一个中小学生高度近视风险预测模型，通过早期识别高风险个体，延缓或阻止高度近视的发展，实现近视的三级预防，对中小学生的学业和生活质量有积极意义。目的探究中小学生高度近视的流行现状及危险因素，构建风险预测模型，为中小学生高度近视防控提供科学依据。方法采用巢式病例对照研究，于2023年选取杭州市12所学校中度近视的学生作为研究对象建立队列，按照全国学生常见病和健康影响因素监测与干预工作方案，对纳入研究的中小学生开展近视状况监测，研究期间进展为高度近视的中小学生作为高度近视发生组，其余未进展为高度近视的中小学生作为对照组，对两组研究对象开展视力保健行为进行调查。采用Lasso回归筛选特征变量后进行多因素Logistic回归分析探究中小学生高度近视发生的影响因素，并采用列线图对风险预测模型可视化，同时采用Hosmer-Lemeshow检验、受试者工作特征（ROC）曲线、Calibration曲线、决策曲线分析（DCA）对模型性能进行评估，最后采用限制性立方样条进一步明确年龄与高度近视发生风险的关系。结果 12所中小学校共纳入2 468名学生，未进展为高度近视的学生1 293名，中度近视进展为高度近视的学生1 175名，高度近视发生率为47.61%(1 175/2 468)。两组学生年龄、年级、BMI、每日入睡时间、地区、户外活动时间、电子产品使用时间、课后作业时间、家用台灯比较，差异有统计学意义（P2 h/d(OR=1.440,95%CI=1.119～1.856)，课后作业时间1～2 h/d(OR=1.461,95%CI=1.126～1.899)、>2 h/d(OR=1.534,95%CI=1.218～1.935)为中小学生高度近视发生的危险因素（P<0.05）；而高中年级（OR=0.560,95%CI=0.419～0.743）为中小学生高度近视发生的保护因素（P<0.05）。基于年级、BMI、每日入睡时间、户外活动时间、电子产品使用时间、课后作业时间等6个变量构建的预测模型ROC曲线下面积为0.840(95%CI=0.825～0.855)，具有良好的拟合优度、一致性、应用性，限制性立方样条分析显示13～15岁为高度近视的高发年龄段。结论中小学生高度近视发生率较高，风险预测模型为高度近视的预防和控制提供了科学依据，应在初中年级加强近视防控措施，改善学生的视力保健行为，降低高度近视的发生。

关键词：近视学生高度近视巢式病例对照研究限制性立方样条预测模型

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A Fuzzy-based Methodology for an Aggregative Environmental Risk Assessment of Restored Soil

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Pedosphere 2014年第2期24卷 220-231页

作者： WANG Shi-Zhong ZHAO Zhi-Hao xia bing QIU Hao J.L.MOREL QIU Rong-Liang School of Environmental Science and Engineering Sun Yat-sen University Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology Laboratoire Sols et Environnement UMR 1120 ENSAIA-INPL/INRA

Environmental risks pertaining to contaminated soils have been well studied,while little attention has been paid to the risks of the soils after remediation. In this study,a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators,namely,plant growth,groundwater safety and human health,of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover,great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general,the risks of both polluted and restored soils to the environment were in the order of groundwater safety > plant growth > human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers,which made it helpful in decision-making and management of restored soils.

关键词： fuzzy set theory heavy metals remediated risk assessment weight distribution