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Abundance and Diversity of RuBisCO Genes Responsible for CO_2 Fixation in Arid Soils of Northwest China

Pedosphere 2015年第1期25卷 150-159页

作者： TANG Zhi-Xi fan Fen-liang WAN Yun-fan WEI Wei LAI Li-Ming State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Ministry of Agriculture Key Laboratory of Agro-Environment and Climate Change Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences

Arid soils where water and nutrients are scarce occupy over 30% of the Earth's total surface. However, the microbial autotrophy in the harsh environments remains largely unexplored. In this study, the abundance and diversity of autotrophic bacteria were investigated, by quantifying and profiling the large subunit genes of ribulose-1,5-bisphosphate carboxylase/oxygenase(Ru Bis CO) form I(cbb L) responsible for CO2 fixation, in the arid soils under three typical plant types(Haloxylon ammodendron, Cleistogenes chinensis,and Reaumuria soongorica) in Northwest China. The bacterial communities in the soils were also characterized using the 16 S r RNA gene. Abundance of red-like autotrophic bacteria ranged from 3.94 × 105 to 1.51 × 106 copies g-1dry soil and those of green-like autotrophic bacteria ranged from 1.15 × 106 to 2.08 × 106 copies g-1dry soil. Abundance of both red- and green-like autotrophic bacteria did not significantly differ among the soils under different plant types. The autotrophic bacteria identified with the cbb L gene primer were mainly affiliated with Alphaproteobacteria, Betaproteobacteria and an uncultured bacterial group, which were not detected in the 16 S r RNA library. In addition, 25.9% and 8.1% of the 16 S r RNA genes were affiliated with Cyanobacteria in the soils under H. ammodendron and R. soongorica, respectively. However, no Cyanobacteria-affiliated cbb L genes were detected in the same soils. The results suggested that microbial autotrophic CO2 fixation might be significant in the carbon cycling of arid soils, which warrants further exploration.

关键词： autotrophic bacteria carbon cycling cbb L harsh environments real-time polymerase chain reaction

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Secure K-Nearest neighbor queries in two-tiered mobile wireless sensor networks

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Digital Communications and Networks 2021年第2期7卷 247-256页

作者： Lihong fan liang Liu Hang Gao Zuchao Ma Yuting Wu Colleages of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China

Tiered Mobile Wireless Sensor Network(TMWSN)is a new paradigm introduced by mobile edge *** it has received wide attention because of its high scalability,robustness,deployment flexibility,and it has a wide range of application *** TMWSNs,the storage nodes are the key nodes of the network and are more easily captured and utilized by *** the storage nodes are captured by the attackers,the data stored on them will be ***,the query process and results will not be trusted any *** paper mainly studies the secure KNN query technology in TMWSNs,and we propose a secure KNN query algorithm named the Basic Algorithm For Secure KNN Query(BAFSKQ)first,which can protect privacy and verify the integrity of query ***,this algorithm has a large communication overhead in most *** order to solve this problem,we propose an improved algorithm named the Secure KNN Query Algorithm Based on MR-Tree(SEKQAM).The MR-Trees are used to find the K-nearest locations and help to generate a verification set to process the verification of query *** can be proved that our algorithms can effectively guarantee the privacy of the data stored on the storage nodes and the integrity of the query *** experimental results also show that after introducing the MR-Trees in KNN queries on TMWSNs,the communication overhead has an effective reduction compared to BAFSKQ.

关键词： TMWSNs Secure KNN queries MR-Tree Privacy Integrity Communication overhead

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Theoretical analysis of persistent fault attack

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Science China(Information Sciences) 2020年第3期63卷 234-239页

作者： fan ZHANG Guorui XU Bolin YANG Ziyuan liang Kui REN College of Information Science and Electronic Engineering Zhejiang University State Key Laboratory of Cryptology School of Cyber Science and Technology Zhejiang University Alibaba-Zhejiang University Joint Institute of Frontier Technologies

Dear editor,Persistent fault attack is a new type of fault attack that was proposed in CHES 2018 [1]. Its success relies on the so-called persistent fault which persists from one encryption to another and disappears w... 详细信息

关键词： Theoretical analysis of persistent fault attack

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Reconstructing Centennial-Scale Water Level of Large Pan-Arctic Lakes Using Machine Learning Methods

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Journal of Earth Science 2023年第4期34卷 1218-1230页

作者： Xinge liang Chunqiao Song Kai Liu Tan Chen Chenyu fan Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China College of Surveying and Geotechnical Engineering Henan Polytechnic UniversityJiaozuo 454000China University of Chinese Academy of Sciences Beijing 100049China

The pan-Arctic region has the largest number of lakes in the world,which is rather sensitive to changing *** is urgently needed to understand how these lakes were changing in the long ***,there are few lakes with long-term historical monitoring of water level,understanding the hydrologic changes of pan-Arctic lakes over the past century requires the data reconstruction by state-of-art *** study used machine learning algorithms to reconstruct the water level of pan-Arctic lakes on a centennial *** further investigated their relationship with long-term hydrological and climatic *** of the reconstructed results by four different machine learning models shows that the extreme gradient boosting tree(XGBoost) is better than other three ***,the centennial-scale reconstruction using the XGBoost model performs best for most study *** on the reconstructed results,we can observe that water level changes of several North American lakes are correlated with potential evapotranspiration,followed by precipitation,while the Eurasian lakes are more strongly associated with temperature and wet day *** water level dynamics of pan-Arctic lakes could be largely attributed to Arctic Oscillation and Atlantic Multidecadal *** study is expected to advance our understanding of the pan-Arctic lake water level changes in the past century and to provide a feasible method for reconstructing the regional lake water level in the long term.

关键词： machine learning water level pan-Arctic lake.

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Commercial cash crop production and households'economic welfare:Evidence from the pulse farmers in rural China

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Journal of Integrative Agriculture 2022年第11期21卷 3395-3407页

作者： MA Ji-liang LI fan ZHANG Hui-jie Khan NAWAB Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Economics and Management Huazhong Agricultural UniversityWuhan 430070P.R.China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Management Sichuan Agricultural UniversityChengdu 611130P.R.China Macro Agriculture Research Institute Huazhong Agricultural UniversityWuhan 430070P.R.China

Whether promoting cash crop production can increase household welfare has long been the focus of the food policy *** study first investigated the determinants of household behavior in commercial pulse *** then examined how households'commercial pulse production improves their economic *** used a dataset of 848 households collected from 2018 to 2019 to estimate the determinants of household behavior in commercial pulse farming by the Heckman two-step *** endogenous treatment regression(ETR)method was employed to examine the impact of commercial pulse farming on household economic *** results showed that factors such as market purchase prices,agricultural technology services,farmers'access to loans,and government subsidies promoted smallholders'commercial pulse farming;production costs and perceptions of climate change risks constrained smallholders'commercial pulse ***,commercial pulse production has increased household farm income but there was a limited impact on household off-farm *** findings suggest that policies aiming to increase households'cash crop production and market access could significantly improve the economic welfare of pulse farmers.

关键词： pulse farming cash crop commercialization economic welfare China

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Insight into the effect of gel drying temperature on the structure and desulfurization performance of ZnO/SiO_(2)adsorbents

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Chinese Journal of Chemical Engineering 2023年第4期56卷 233-241页

作者： Chao Yang Zhelin Su Yeshuang Wang Huiling fan Meisheng liang Zhaohui Chen College of Environmental Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

A series of ZnO/SiO_(2) adsorbents were prepared by a sol-gel method using tetraethyl orthosilicate,ethylene glycol(EG)and nitrates as *** effect of gel drying temperature on the structure and desulfurization performance of the adsorbents were investigated in *** is found that the low drying temperature led to a weak interaction among EG,Si AOH/H_(2)O and the nitrates in the gel system,which caused the oxidation of EG by NO3-and formed zinc glyoxylate complex during the gel calcination process,whereas this oxidation process also occurred at a high drying temperature during the gel drying *** formed zinc glyoxylate complex promoted the generation of monodentate carbonate on the surface of Zn O,which resulted in the inferior desulfurization performance of adsorbents despite they have smaller Zn O *** gel dried at 120°C formed the hydrogen bonds between EG and Si AOH/H_(2)O and a strong interaction between zinc oxo-clusters and NO3-was also found in the gel system,which avoided the oxidation of EG by NO3-during the preparation process and the Zn O nanoparticles with sizes of 6 nm were formed by a combustion *** adsorbent affords a highest sulfur capacity of 104.9 mg·g^(-1) in this *** addition,the gel drying temperature has a significant influence on the textural properties of the adsorbents except their surface area.

关键词： Sol-gel method Drying temperature H_(2)S removal Zinc-silica composites Hydrogen bonds

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Nitrogen nutrition diagnosis for cotton under mulched drip irrigation using unmanned aerial vehicle multispectral images

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Journal of Integrative Agriculture 2023年第8期22卷 2536-2552页

作者： PEI Sheng-zhao ZENG Hua-liang DAI Yu-long BAI Wen-qiang fan Jun-liang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F UniversityYangling712100P.R.China

Remote sensing has been increasingly used for precision nitrogen management to assess the plant nitrogen status in a spatial and real-time *** nitrogen nutrition index(NNI)can quantitatively describe the nitrogen status of ***,the NNI diagnosis for cotton with unmanned aerial vehicle(UAV)multispectral images has not been evaluated *** study aimed to evaluate the performance of three machine learning models,i.e.,support vector machine(SVM),back propagation neural network(BPNN),and extreme gradient boosting(XGB)for predicting canopy nitrogen weight and NNI of cotton over the whole growing season from UAV *** results indicated that the models performed better when the top 15 vegetation indices were used as input variables based on their correlation ranking with nitrogen weight and *** XGB model performed the best among the three models in predicting nitrogen *** prediction accuracy of nitrogen weight at the upper half-leaf level(R^(2)=0.89,RMSE=0.68 g m^(-2),RE=14.62%for calibration and R^(2)=0.83,RMSE=1.08 g m^(-2),RE=19.71%for validation)was much better than that at the all-leaf level(R^(2)=0.73,RMSE=2.20 g m^(-2),RE=26.70%for calibration and R^(2)=0.70,RMSE=2.48 g m^(-2),RE=31.49%for validation)and at the plant level(R^(2)=0.66,RMSE=4.46 g m^(-2),RE=30.96%for calibration and R^(2)=0.63,RMSE=3.69 g m^(-2),RE=24.81%for validation).Similarly,the XGB model(R^(2)=0.65,RMSE=0.09,RE=8.59%for calibration and R^(2)=0.63,RMSE=0.09,RE=8.87%for validation)also outperformed the SVM model(R^(2)=0.62,RMSE=0.10,RE=7.92%for calibration and R^(2)=0.60,RMSE=0.09,RE=8.03%for validation)and BPNN model(R^(2)=0.64,RMSE=0.09,RE=9.24%for calibration and R^(2)=0.62,RMSE=0.09,RE=8.38%for validation)in predicting *** NNI predictive map generated from the optimal XGB model can intuitively diagnose the spatial distribution and dynamics of nitrogen nutrition in cotton fields,which can help farmers implement precise cotton nitrogen management in a t

关键词： UAV nitrogen diagnosis leaf nitrogen weight nitrogen nutrition index cotton

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Fabrication of high-stability Ni-PSF@PAO40 microcapsules and their lubricating properties in polyamide 6

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Friction 2022年第12期10卷 1985-1999页

作者： Wenli ZHANG Xiaowen QI Xiao YANG Yu DONG Bingli fan Lei liang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Key Laboratory of Self-Lubricating Spherical Plain Bearing technology of Hebei Province Yanshan UniversityQinhuangdao 066004China Aviation Key Laboratory of Science and Technology on Generic Technology of Self-Lubricating Spherical Plain Bearing Yanshan UniversityQinhuangdao 066004China School of Civil and Mechanical Engineering Curtin UniversityPerthWA 6845Australia Shanghai Research Institute of Synthetic Resins Co. Ltd.Shanghai 201702China

Novel Ni-PSF@PAO40 microcapsules(NPPMS)with high stability were prepared by using a combined processing method of electroless nickel plating and solvent *** results indicate that Ni is completely assembled on the surfaces of PSF/PAO40 microcapsules with the encapsulation capacity of NPPMS achieved at 50%.Organic solvents immersion shows that NPPMS have an excellent chemical *** thermal stability tests reveal that the softening temperature of NPPMS is increased up to over 400℃ while it becomes lower than 200℃ for PSF/PAO40 ***,NPPMS were embedded into polyamide 6(PA6)to prepare PA6/NPPMS *** cross-sectional morphology shows that NPPMS are intact in PA6 *** microhardness of PA6 is effectively improved with the incorporation of *** compared with neat PA6,the coefficient of friction(COF)for PA6/NPPMS composites with 10%NPPMS could be reduced by 87.7%(from 0.49 to 0.06)and the wear rate could be decreased by 96.8%(from 1.29×10^(-5) to 4.15×10^(-7) mm^(3)/(N·m)).Further studies confirmed that increasing test loads and test temperatures was beneficial to improve the lubrication performance of NPPMS despite the opposite trend occurred when increasing the sliding *** has been demonstrated that synergistic effects between PAO40 and Ni layer play an important role in improving the tribological properties of ***,NPPMS significantly improve the ability of microcapsules to resist a harsh environment,which has important scientific significance for expanding the use of microcapsules more practically in self-lubricating composites.

关键词： microcapsules electroless nickel high temperature resistant polyamide 6(PA6) friction and wear

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Enhanced stability of Fe-modified CuO-ZnO-ZrO_(2)-Al_(2)O_(3)/HZSM-5 bifunctional catalysts for dimethyl ether synthesis from CO_(2)hydrogenation

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Chinese Journal of Chemical Engineering 2021年第10期34卷 106-113页

作者： Xiao fan Shoujie Ren Baitang Jin Shiguang Li Miao Yu Xinhua liang Department of Chemical and Biochemical Engineering Missouri University of Science and TechnologyRollaMO 65409United States Gas Technology Institute 1700 South Mount Prospect RoadDes PlainesIL 60018United States Department of Chemical and Biological Engineering Rensselaer Polytechnic InstituteTroyNY 12180United States

A series of iron(Fe)modified CuO-ZnO-ZrO_(2)-Al_(2)O_(3)(CZZA)catalysts,with various Fe loadings,were prepared using a co-precipitation method.A bifunctional catalyst,consisting of Fe-modified CZZA and HZSM-5,was studied for dimethyl ether(DME)synthesis via CO_(2)*** effects of Fe loading,reaction temperature,reaction pressure,space velocity,and concentrations of precursor for the synthesis of the Fe-modified CZZA catalyst on the catalytic activity of DME synthesis were ***-term stability tests showed that Fe modification of the CZZA catalyst improved the catalyst stability for DME synthesis via CO_(2)*** activity loss,in terms of DME yield,was significantly reduced from 4.2%to 1.4%in a 100 h run of reaction,when the Fe loading amount was 0.5(molar ratio of Fe to Cu).An analysis of hydrogen temperature programmed reduction revealed that the introduction of Fe improved the reducibility of the catalysts,due to assisted adsorption of H2 on iron *** good stability of Femodified CZZA catalysts in the DME formation was most likely attributed to oxygen spillover that was introduced by the addition of iron *** could have inhibited the oxidation of the Cu surface and enhanced the thermal stability of copper during long-term reactions.

关键词： CO_(2)hydrogenation Cu-ZnO based catalyst Iron(Fe) Dimethyl ether(DME) Stability

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Self-assembly of metal-cholesterol oxidase hybrid nanostructures and application in bioconversion of steroids derivatives

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Frontiers of Chemical Science and Engineering 2021年第3期15卷 615-629页

作者： Yu Xin Qiuyue Gao Yu Gu Mengyao Hao Guangming fan liang Zhang Key Laboratory of Industry Biotechnology(Ministry of Education) School of BiotechnologyJiangnan UniversityWuxi 214122China National Engineering Laboratory for Cereal Fermentation Technology Jiangnan UniversityWuxi 214122China

A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were *** scanning electron microscopy assays,the metal-COD complexes revealed flower-like or granular structures after *** transform infrared spectroscopy assay revealed the characteristic peaks of both the enzyme and metal materials.X-ray diffraction analysis indicated that COD was encapsulated in CaHPO_(4)·2H_(2)O-,Zn_(3)(PO_(4))_(2)·4H_(2)O-,AlPO_(4-),FeP_(4-) and Mn_(3)(PO_(4))_(2)·3H_(2)O-based nanostructures,*** scanning calorimetry assay indicated significant increases in thermo-denaturation temperatures from 60.5℃ to 167.02℃,167.02℃,137.70℃,172.85℃ and 160.99℃,*** steroid derivatives as substrates,this enzyme could convert cholesterol,pregnenolone,dehydroepiandrosterone,ergosterol,b-sitosterol and stigmasterol to related single *** in metal-based nanostructures could significantly enhance the initial conversion ratio and reaction stability of the *** addition,substrate selectivity could be affected by various metal ***,using Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+) as hybrid raw materials could help to encapsulate COD in related metal-enzyme nanostructures,and could help to promote the stability and tolerant properties of the enzyme,while also enhancing its catalytic characteristics.

关键词： cholesterol oxidase metal-enzyme hybridization nanostructures sterol derivatives bioconversion

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