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Semi-Homogenous Generalization： Improving Homogenous Generalization for Privacy Preservation in Cloud Computing

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Journal of Computer Science & Technology 2016年第6期31卷 1124-1135页

作者： Xian-Mang He Xiaoyang SeanWang Dong Li Yan-ni hao School of Information Science and Engineering Ningbo University Ningbo 315211 China School of Computer Science Fudan University Shanghai 200433 China Information Center National Natural Science Foundation of China Beijing 100085 China

Data security is one of the leading concerns and primary challenges for cloud computing. This issue is getting more and more serious with the development of cloud computing. However, the existing privacy-preserving data sharing techniques either fail to prevent the leakage of privacy or incur huge amounts of information loss. In this paper, we propose a novel technique, termed as linking-based anonymity model, which achieves K-anonymity with quasi-identifiers groups （QI-groups） having a size less than K. In the meanwhile, a semi-homogenous generalization is introduced to be against the attack incurred by homogenous generalization. To implement linking-based anonymization model, we propose a simple yet efficient heuristic local recoding method. Extensive experiments on real datasets are also conducted to show that the utility has been significantly improved by our approach compared with the state-of-the-art methods.

关键词： privacy preservation cloud computing linking-based anonymization semi-homogenous homogenous generalization

Superior Ductile and High-barrier Poly(lactic acid)Films by Constructing Oriented Nanocrystals as Efficient Reinforcement of Chain Entanglement Network and Promising Barrier Wall

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Chinese Journal of Polymer Science 2022年第10期40卷 1201-1212,I0009页

作者： Lin Zhou Ping-Ping Xu Shi-hao ni Ling Xu hao Lin Gan-Ji Zhong Hua-Dong Huang Zhong-Ming Li Collge of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

It is a daunting task to develop a promising strategy at an industrial scale for simultaneously ameliorating ductility and gas barrier performance of poly(lactic acid)(PLA)films in the application of green *** this work,biaxial stretching and constrained annealing were employed to prepare transparent PLA films with superior ductility and barrier *** oriented nano-sized crystals induced by biaxial stretching were developed into regularαform during constrained annealing,which could not only serve as“nano-barrier wall”to impede the diffusion and dissolution of gas molecules,but also strengthen amorphous chain entanglement network as physical crosslink to enhance *** a result,the as-prepared PLA films exhibited an outstanding comprehensive performance with a low oxygen and water vapor permeability coefficient of 0.733×10^(-14) cm^(3)·cm·cm^(-2)·s^(-1)·Pa^(-1) and 3.82×10^(-14) g·cm·cm^(-2)·s^(-1)·Pa^(-1),respectively,outstanding ductility with elongation at break of 66.0%,high yield strength of 84.2 MPa,and good transparency of more than 80%at 550 *** new insight in the relationship between microscopic amorphous and crystalline structure and macroscopic performance is conducive to alleviating the intrinsic defects of brittle and insufficient barrier PLA films without the aid of any heterogenous modifiers,facilitating their widespread commercialization in the booming sustainable packaging market.

关键词： Poly(lactic acid)films Biaxial stretching Constrained annealing Gas barrier properties Ductility

Urban Renewal Mapping:A Case Study in Beijing from 2000 to 2020

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Journal of Remote Sensing

Journal of Remote Sensing 2023年第1期3卷 310-333页

作者： hao ni Le Yu Peng Gong Xuecao Li Jiyao Zhao Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceTsinghua UniversityBeijing 100084China Tsinghua University(Department of Earth System Science)–Xi’an Institute of Surveying and Mapping Joint Research Center for Next-Generation Smart Mapping Beijing 100084China Department of Geography Department of Earth Sciences and Institute for Climate and Carbon NeutralityUniversity of Hong KongHong KongChina College of Land Science and Technology China Agricultural UniversityBeijing 100083China

Understanding the distribution and land history of old urban areas(OUAs)and renewed urban areas(RUAs)has become the key point of urban ***,it is hard to acquire adequate information for lack of pertinent detection ***,we established a complete mapping framework on Google Earth Engine(GEE)platform to identify OUAs and RUAs and detect the temporal information of urban renewal,which was implemented in Beijing during *** used Landsat imagery and LandTrendr algorithm to fit the spectral trajectories of 14 bands/indices with specific segment attributes as the feature inputs for Random Forest *** produced the maps of OUAs and RUAs with an overall accuracy of 95.36%.On this basis,we further utilized LandTrendr to detect the start year,end year,and duration of urban renewal with the accuracies within the±5-year difference of 85.52%,80.97%,and 74.53%,*** maps all present informative spatiotemporal ***,the urban renewal process is likely to be influenced by major national or international *** study answers the issues about urban renewal from multiple angles and provides scientific support for future urban planning.

关键词： urban utilized renewal

The preparation of grid-textured V2O5 films and their potential applications in gas sensing

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Science China(Technological Sciences) 2020年第3期63卷 467-471页

作者： CHENG Rong HUANG WeiYi LIU XiangBo LING Francis Chi Chung GAO Ju ni hao Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Physics The University of Hong KongHong KongChina College of Science China University of Petroleum(Huadong)Qingdao 266580China

Novel nano-structured films of V2O5 are prepared by pulsed laser deposition method. Nanoscaled V2O5 ridges lie on SrTiO3 substrate and construct into grid-textured structures. Structural properties of the films have been analyzed by scanning electron microscope, X-ray diffraction and transmission electron microscope. The films have enlarged surface-to-volume ratio due to the ridge-channel structure which makes them applicable to gas sensing. Therefore, gas sensors based on the V2O5 films have been assembled which present reliable sensing properties to gaseous acetone, and ethanol at room temperature. The physical-chemical reactions between adsorbed O2^– and testing gases are the possible reason for this property.

关键词： V2O5 thin film gas sensing

Hybrid perovskite shows temperature-dependent photoluminescence and dielectric response triggered by halogen substitution

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Chinese Journal of Structural Chemistry 2024年第6期43卷 28-33页

作者： Xiao-Tong Sun hao-Fei ni Yi Zhang Da-Wei Fu Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing211189People's Republic of China Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua321004People's Republic of China

Materials exhibiting dielectric switching response and photoluminescence(PL)are promising for sensors and information *** previous research,we synthesized a series of materials with red or green PL and dielectric switching capabilities by incorporating luminescent metal halides into organic ammonium ***,effective modification to synthesize organic-inorganic hybrid materials with dielectric switching response and orange PL continues to be a challenge in the respective *** PL materials are valuable for switching and sensors,and most orange light sources are derived from rare earth elements,making them harder to *** have successfully synthesized two organic-inorganic hybrid materials([CMPD]PbBr_(3)(1)and[BMPD]PbBr_(3)(2),CMPD=N-ClCH_(2)-N-methylpiperidine,BMPD=N-BrCH_(2)-N-methylpiperidine)that exhibit both orange PL and dielectric switching *** Cl in compound 1 is substituted by Br in compound 2,the phase transition temperature of the compound is elevated by 45 *** compounds exhibit captivating orange light emission when exposed to ultraviolet *** research provides insights into exploring multifunctional materials with orange PL and dielectric switching response and provides proof for halogen substitution strategies to design materials with higher phase transition temperatures.

关键词： Dielectric switching Photoluminescence Orange

Thermocatalytic Dehydrogenation-Enabled Arene-Alkane Couplings

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Chinese Journal of Chemistry 2023年第16期41卷 1905-1914页

作者： Feng Yu Renqing Tao Lan Gan hao ni Qi-Kai Kang Guixia Liu Zheng Huang Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China School of Chemistry and Material Sciences Hangzhou Institute of Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China

Comprehensive Summary The direct use of non-prefunctionalized arene and alkane as the starting materials to construct Caryl−Calkyl bond is an unfulfilled target and approaches to this challenge rarely surface in methodology *** methods for thermocatalytic arene-alkane couplings(AAC)occur with specific substrates and/or inconvenient ***,we report a one-pot relay bicatalysis system for AAC involving(pincer)Ir-catalyzed alkane transfer dehydrogenation and Fe(OTf)3-catalyzed olefin *** system exhibits broad scope and is particularly effective for alkylation of arenes with arylalkanes to form 1,1-diarylalkanes with high chemo-and regioselectivity,making it potentially useful for late-stage alkylation of complex *** mechanistic data provide a view into the factors controlling the ***,the strategy of dehydrogenation-enabled arene-alkane couplings has been successfully extended to a tandem catalysis by using a heterogeneous olefin hydroarylation catalyst.

关键词： Alkanes Arenes Dehydrogenative coupling Hydroarylation lridium

Giant negative photoresistance of epitaxial manganite La2/3Ca1/3MnO3-δ film

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Science China(Information Sciences) 2015年第12期58卷 204-210页

作者： XI JianFeng Zhao Kun ni hao XIANG WenFeng FENG Xin SUN Qi LU ZhiQing XIAO LiZhi State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum

The La2/3Ca1/3Mn O3-δ film has been deposited on the(001) Sr Ti O3 substrate and its temperature-dependent photoconductive properties have been investigated from 80 to 300 K. The La2/3Ca1/3Mn O3-δfilm has a novel photoelectric property due to its oxygen-deficient structure. We observed laser-induced giant negative photoresistance of the sample in a wide temperature range. The change rate of negative photoresistance was nearly 100% at the low temperature when the sample was irradiated by 532 nm laser. In addition, this effect was sensitive to the power of laser irradiation. The oxygen-deficiency of La2/3Ca1/3Mn O3-δfilm seems to have an impact on the laser-induced resistance variation. The experimental results made the La2/3Ca1/3Mn O3-δfilm a promising application as a photoswitch device.

关键词： giant negative photoresistance oxygen-deficient photoswitch thin film manganite oxide

Physiological response and phenolic metabolism in tomato (Solanum lycopersicum) mediated by silicon under Ralstonia solanacearum infection

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Journal of Integrative Agriculture 2018年第10期17卷 2160-2171页

作者： FAN Xue-ying LIN Wei-peng LIU Rui JIANG ni-hao CAI Kun-zheng College of Natural Resources and Environment/Key Laboratory of Tropical Agro-environment Ministry of Agriculture South China Agricultural University Laboratory of Ecotoxicity and Environmental Safety Guangdong Detection Center of Microbiology Guangdong Institute of Microbiology Tea Research Institute Guangdong Academy of Agricultural Sciences

Bacterial wilt, caused by Ralstonia solanacearum（Rs） is a serious soil-borne disease and silicon can enhance tomato resistance against this disease. However, few studies have focused on the mechanisms of Si-mediated pathogen resistance from the rhizosphere perspective. In this study, two tomato genotypes, HYT（susceptible） and H7996（resistant）, were used to investigate the effects of silicon application on disease inhibition, root growth, and organic acid content in both roots and root exudates under R. solanacearum infection. The results showed that Si application significantly suppressed bacterial wilt in HYT, but had no effect in H7996. Silicon concentrations in roots, stems and leaves of tomato were significantly increased by Si treatment under R. solanacearum inoculation. In HYT, Si application increased root dry weight by 22.8-51.6% and leaf photosynthesis by 30.6-208.0%, and reduced the concentrations of citric acid in root exudates by 71.4% and in roots by 83.5%. However, organic acids did not influence R. solanacearum growth. Results also demonstrated that salicylic acid（SA） content in roots was significantly increased by silicon addition for H7996 and exogenous SA application could reduce bacterial wilt disease index. Collectively, these results suggest that Si-modulated phenolic compound metabolism in roots or root exudates, especially citric acid and SA, may be a potential mechanism in the amelioration of bacterial wilt disease by Si.

关键词： silicon root root exudates Solanum lycopersicum Ralstonia solanacearum organic acids

Is the metal involved or not? A computational study of Cu(I)-catalyzed [4+1] annulation of vinyl indole and carbene precursor

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Chinese Chemical Letters 2022年第4期33卷 2031-2035页

作者： Xiaoqian He Kangbao Zhong Dan Heng Zhen Zeng hao ni Ruopeng Bai Yu Lan School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China College of Chemistry and Institute of Green Catalysis Zhengzhou UniversityZhengzhou 450001China

The Cu(I)-catalyzed [4 + 1] annulation of vinyl indoles and a carbene precursor is a powerful method for constructing cyclopentaindole derivatives. Density functional theory(DFT) calculations were used to elucidate the mechanism and regioselectivity of this reaction. After Cu-assisted indole C3-alkylation, direct1,5-annulation was favored over the Cu-assisted annulation pathway. Furthermore, the regioselectivity for1,5-annulation was attributed to the generated five-membered-ring product being more stable than the three-membered-ring product from 1,3-annulation, which was the kinetically favored pathway.

关键词： Carbene precursor Regioselectivity DFT calculations Cyclopentaindol C3-alkylation